ISSN:0365-6217    

DOI:10.1039/AR95350FP001

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

ERRATA.Vol. 49, 1952.Page. Line.109 4* For dinitro-(N-ethyl-N-methylglycine)platinate(II) read potas-183 - Formulx (LIII) and (LIV) should readsium dinitro- (N-ethyl-N-methylglycine) platinate (11).195 - T h e sentence beginning Hydrogenation of the double bond . . .should be moved forward to pvecede that beginning This micro-biological hydroxylation . . .* From bottom of main text

ISSN:0365-6217    

DOI:10.1039/AR9535000008

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

ANNUAL REPORTSON THEPROGRESS OF CHEMISTRY.GENERAL AND PHYSICAL CHEMISTRY.1. MOLECULAR SPECTRA.SOME sections of this survey provide a continuation of subjects reported in1952.lMolecular Dimensions.-Much effort has been directed to the more precisedetermination of molecular dimensions. Pure rotational spectra in themicro-wave region and the far infra-red, and the Raman effect have been used,together with detailed analyses of the rotational fine structure of vibrationalbands in the near and photographic infra-red and in Raman spectra.Methane has been studied as such by Raman spectroscopy,2 as methane3and deuteromethane by absorption in the 3-p region, and as mono- andtri-deuteromethane 6 in the first overtone 7 and photographic infra-red. Theresults for monodeuteromethane give ro = 1-0936 A, and for trideutero-methane yo = 1.0919 fi.A difference in this sense is to be expected becauseof zero-point energy. However, for methane ro is found unexpectedly to be1.0931, which is between the value for monodeuteromethane and that fortrideuteromethane. The Q-branch of a band of 13CH4 has also been studied.Nitrous oxide provides a comparison between the results of micro-waveand infra-red spectroscopy. Values obtained for B, for the lowest vibrationstate (in Mc./sec.) are : Micro-wave J , 0-1 transition, 12561.64; J , 1-2transition, 12561.55 5 0-025; J , 3 - 4 and 4-5 transitions, 12561.65 -&0.025; lo vibration bands near 1 p, 12564.5; l1 vibration band near 4-5 p,12565-3 & 4-5.12 The results demonstrate the accuracy obtainable.Ifvalues of B are measured for enough excited vibrational states, correctionscan be made and the equilibrium configuration determined. Values of B forexcited states can be obtained from fundamental and overtone bands in theJ. W. Linnett, Ann. Reports, 1952, 49, 7.B. P. Stoicheff, C. Cumming, G. E. St, John,and H. L. Welsh, J . Chem. Phys., 1952,20, 498.A. H. Nielsen and H. H. Nielsen, Phys. Review, 1935, 48, 864; D. R. J. Boyd,H. W. Thompson, and R. L. Williams, PVOG. Roy. Soc., 1952, A , 213, 42.D. R. J . Boyd and H. W. Thompson, ibid., 1953, A , 216, 143.W. H. J. Childs and H. A. Jahn, ibid.. 1939, A , 169, 428.L. F. H. Bovey, J . Chem. Phys., 1953, 21, 830.T. A. Wiggins, E. R. Shull, J. M. Bennett, and D.H. Rank, ibid., p. 1940.D. K. Coles, E. S. Elyash, and J. G. Gorman, Phys. Review, 1947, 72, 973.S. J . Tetenbaum, ibid., 1952, 88, 772.lo C. M. Johnson, R. Trambarulo, and W. Gordy, ibid., 1951, 84, 1178.l1 G. Herzberg and L. Herzberg, J . Chern. Phys., 1950, 18, 551.l2 H. W. Thompson and R. L. Williams, Proc. Roy. Soc., 1951, A , 208, 32610 GENERAL AND PHYSICAL CHEMISTRY.infra-red. If rotational transitions can be observed for molecules in excitedvibrational states, it is also possible to determine them by using the micro-wave spectrum. This can be done only when the vibrational quanta aresmall, and has been achieved in part for carbonyl sulphide and cyanogenbromide. l3 When a molecule possesses larger vibration frequencies infra-red spectra must be used to obtain Be, the rotational constant for the equili-brium configuration.Ivash and Dennison l4 have made calculations on methyl alcohol by usingmicro-wave data.15 The dimensions for the lowest vibrational state are :CH, OH, and CO bond-lengths 1-093,0.937, and 1.434, and CCH and HcHangles 105" 56' and 109" 30' (cf.0.958 and 104" 31' in H20 Is). The oxygenatom does not lie on the symmetry axis of the methyl group but 0.079 fromit. The barrier height, a sinusoidal potential being assumed, was 374.8 cm.-l(1071 cals.). .The micro-wave spectra of SiD3C1,17 SiD,F,18 HSiC13,19 CH3SiCl3,19(CH3)3SiCI,19 HGeC1,,20 CH2C1F,2l (CH3),CF,22 and CF&1 2, have beenAexamined. In HGeCI, the ClGeC1 angle is 108" 17' & 12'.This shows that,when C1-Cl repulsion is minimised, chlorine can, like fluorine (cf. HCF, 24 andHGeF, 25), lead to a reduction in the inter-bond angle below the tetrahedralvalue. In CH2ClF 21 the Cl?F angle (110" 1') is greater than 109" 28', but itis surprising that the opposite HCH angle (111" 56') is also greater than thetetrahedral. In CH,ClF, the C-C1 bond length is 1-759 A, which is less thanthat in CH,C1 (1.779),26 but about the same as that in carbon tetrachloride(1.755) ; 26 while in CF,Cl it is 1-74 A, which is less than in carbon tetra-chloride. The effect in CF,C1 has been explained by resonance but it might,equally, be due to the high electronegativity of fluorine.Several diatomic molecules have been examined by micro-wave andinfra-red spectroscopy.Thompson and his co-workers have analysed thefundamental bands of hydrogen chloride,27 deuterium chloride,28 13C160 and12C180.29 The results for carbon monoxide are consistent with the data ofPlyler et aZ.,O and with micro-wave 31 and ultra-violet results.32 Hansler13 S. J. Tetenbaum, Phys. Review, 1952, 86, 440.I4 E. V. Ivash and D. M. Dennison, J . Chem. Phys., 1953, 21, 1804.l5 W. D. Hershberger and J. Turkevich, Phys. Review, 1947, 71, 554; 13. P. Dailey,ibid., 1947, 72, 84; D. K. Coles, ibid., 1948, 74, 1194; R. H. Hughes, Mr. E. Good, andD. K. Coles, ibid., 1951, 84, 418.l6 B. T. Darling and D. M. Dennison, ibid., 1940, 57, 128.l7 €3. Bak, J. Bruhn, and J. Rastrup-Andersen, .{. Chem. Plzys., 1953, 21, 753.l8 Idem, ibid., p.752.23 P. Venkateswarlu, R. C. Mockler, and W. Gordy, ibid., p. 1713.21 N. Muller, J . Amer. Chem. SOC., 1963, 75, 860.22 F. Andersen, J. Rastrup-Andersen, B, Bak, 0. Bastiansen, E. Risberg, and23 J. Sheridan and W. Gordy, ibid., 1952, 20, 591.24 S. N. Ghosh, R. Trambarulo, and W. Gordy, ibid., p. 605.25 W. E. Andersen, J. Sheridan, and W. Gordy, Phys. Review, 1951, 81, 819.26 P. W. Allen and L. E. Sutton, Acta Cryst., 1950, 3, 48.2 7 I. M. Mills, H. W. Thompson, and R. L. Williams, Proc. Roy. soc., 1953, A , 218. 29.2 8 J . Pickworth and H. W. Thompson, ibid., p. 37.*S I. M. Mills and H. W. Thompson, Tra?zs. Faraday s o s . , 1953, 49, 224.39 E. K. Plyler, W. S. Benedict, and S. Silverman, J . Clzem. Phys., 1952, 20, 175.31 0.R. Gdliam, C . M. Johnson, and ?V. Gordy, Phys. Review, 1956, 78, 140.32 I<. E. McCulloh and G. Glockler, ibid., 1953, 89, 145.AID R. C. Mockler, J. H. Bailey, and W. Gordy, ibid., p. 1710.L. Smedvik, J . Chem. Phys., 1953, 21, 373LINNETT : MOLECULAR SPECTRA. 11and Oetjen have studied the pure infra-red rotational spectra of hydrogenchloride, deuterium chloride, hydrogen bromide, and ammonia with agrating spectrometer ; 33 the results for the diatomic molecules agree with thedata compiled by Herzberg34 who gives 1.27460 and 1.274, A for re forhydrogen chloride and deuterium chloride. Thompson et al. give for these1.274, 27 and 1.2746 28 A. The micro-wave spectra of l6ol60 and l6oi70have been measured,35 and the effect of added gases on the line breadth hasbeen used to determine molecular collision diameters.36The micro-wave spectrum of the hydroxyl radical has been observed bystreaming water vapour through a discharge tube and then into the absorptioncell.,' The authors conclude that the proportion of hydroxyl radical is a fewtenths of l%, and that it should be possible to study " hydroxyl radicalsproduced by a variety of chemical reactions, and that other free radicals mayprove accessible to micro-wave techniques." This may mark the beginningof an important application of micro-wave spectroscopy.The micro-wave spectrum of ozone has been studied by Hughes 38 and byTrambarulo et aL39 The former gives the bond length as 1.276-1.279 andthe angle as 116~-117°, 10" less than the value obtained by electrondiffraction.The latter authors give 1.278 & 0.003 A and 116" 49' zt 30'.Another interesting molecule studied by micro-wave spectroscopy is chlorinetrifluoride.40 It is T-shaped with one bond length of 1-598 and two of1.698 A ; the interbond angle is 87" 29' (X-ray diffraction results 41 oncrystalline chlorine trifluoride confirm the shape, giving for the dimensions1.621, 1.716, and 86" 59'). This molecule appears to be based on a trigonalbipyramid in which two equatorial positions are occupied by lone pairs ofelectrons. The tendency of fluorine to cause a decrease in FXF bond anglesis also in evidence here.,2There has been some work during the year 011 ammonia3, and relatedmolecules.43 The pure rotation spectrum of ND, from 60 to 200 cni.-l hasbeen examined ; 44 the value determined for the centrifugal distortioncoefficient agrees with that to be expected. The micro-wave spectrum ofND, has been measured,45 and also the fine structure of an NH, band appear-ing in the Raman spectrum.46 Coriolis coefficients of these molecules havebeen discussed.47The molecular dimensions of benzene have been determined from therotational Raman spectrum of the vapour ; 48 B, = 0.18955 5 0.00005, andDo = 1.2 x cm.-l If the C-H length is between 1.06 and 1-09 A, the33 R.L. Hansler and R. A. Oetjen, J . Chern. Phys., 1953, 21, 1340.34 G. Herzberg, " Spectra of Diatomic Molecules," Van Nostrand, New York, 1950,3G R. S. Andersen, W. V. Smith, and W. Gordy, ibid., 1952, 87, 561.37 T.M. Saunders, A. L. Schawlow, G. C. Doumanis, and C. H. Townes, ibid., 1953,R. Trambarulo, S. N. Ghosh, C. A. Burrus, and W. Gordy, J . Chem. Phys., 1953,/\p. 534.89, 1159.21, 851.35 S. L. Miller and C. H. Townes, Phys. Review, 1953, 00, 537.38 R. H. Hughes, ibid., 1952, 85, 717.I 0 D. G. Smith, ibid., p. 609.41 R. D. Burbank and F. N. Bensey, ibid., p. 602.42 C. E. Mellish and J. W. Linnett, to be published.43 V. M. McConaghie and H. H. Nielsen, J . Chem. Phys., 1953, 21, 1836; W. H.4r'R. E. Stroup, R. A. Oetjen, and E. E. Bell, ibid., p. 2072.4 5 R. G. Nuckolls, L. J. Ruiger, and H. Lyons, Phys. Review, 1953, 89, 1101.d6 C. Cumming and H. L. Welsh, J . Chewz. Phys., 1953, 21, 1119.4 7 H. H. Nielsen, ibid., p. 142.Haynie and H.H. Nielsen, ibid., p. 1839.48 B. Stoicheff, ibid., p. 141012 GENERAL AND PHYSICAL CHEMISTRY.C-C length is between 1.396 and 1.401 A. The spectra of hydrogen cyanideand deuterium cyanide between 0.5 and 2-5 p give 1.0657 and 1.1530 for theequilibrium C-H and C-N bond lengths.49 The pure rotational spectra ofhydrogen cyanide and deuterium cyanide have also been studied, givingbond lengths for the ground vibrational states.”Other molecules that have been examined are SOF,,51 S02Cl,,52 COCl,,53CH,I, e t ~ . , ~ ~ D20,55 HD0,56 HCNS,57 C5H,N,5* C,H,NH,59 NaCl and CsC1,G0C8H13C1 and C8Hl,Br,61 PH2D and PD,H,62 C2N2,63 C,H2,63 CH3*C--CH,63DI,64 and H,S.65Molecular Vibrations-The vibrational spectra of simple polyatornicmolecules continue to be investigated extensively.A number of fluorine-substituted ethanes 66 and aromatic compounds 67 have been studied;Cleveland, Meister, and their co-workers have continued their examinationof substituted methanes 68 and other simple molecules ; 69 and several siliconcompounds have been in~estigated.~O More work has been carried out onrotational isomerism. 7149 A. E. Douglas and D. Sharma, J . Chem. Phys., 1953, 21, 448.50 A. H. Nethercot, J. A. Klein, and C. H. Townes, Phys. Review, 1952, 86, 798;J. W. Simmons, R. S. Andersen, and W. Gordy, ibid., p. 1055; T . L. Weatherly and D.Williams, ibid., 1952, 87, 517. 61 R. C. FergusonandE. B. Wilson, ibid., 1953, 90, 338.52 R. M. Fristrom, ibid., 1952, 85, 717.53 G. W. Robinson, J . Chem.Phys., 1953, 21, 1741.64 T. A. Wiggins, E. R. Shull, and D. H. Rank, ibid., p. 1368.55 W. S. Benedict, N. Gailar, and E. K. Plyler, ibid., p. 1301.66 Idem, ibid., p. 1302; D. W. Posener and M. W. P. Strandberg, ibid., p. 1401.5 7 G. C. Dournanis, T. M. Sanders, C. H. Townes, and H. J. Zeiger, ibid., p. 1416.5 8 B. Bak and J. Rastrup-Andersen, ibid., p. 1306.59 W. S. Wilcox, K. C. Brannock, W. DeMore, and J. H. Goldstein, ibid., p. 563;6J M. L. Stitch, A. Honig, and C. H. Townes, Phys. Review, 1952, 86, 813.61 A. H. Nethercot and A. Javan, J . Chem. Phys., 1953, 21, 363.62 R. E. Stroup and R. A. Oetjen, ibid., p. 2092; M. H. Sirvetz and R. E. Weston,ibid., p. 898.63 D. R. J. Boyd and H. W. Thompson, Trans. Farnday Soc., 1953, 49, 141; G. D.Craine and H.W. Thompson, ibid., p. 1273.64 J. A. Klein and A. H. Nethercot, Phys. Review, 1953, 91, 1018.6 5 C. A. Burrus and W. Gordy, ibid., 1953, 92, 274; W. Gordy and W. C. King,ibid., 1953, 90, 319.6 6 J. R. Nielsen, C. Y. Liang, R. M. Smith, D. C. Smith, M. Alpert, and C. W. Gul-likson, J . Chem. Phys., 1953, 21, 383, 1060, 1070, 1416. See also D. E. Mannand E. K.Plyler, ibid., p. 1116.6 7 J. R. Nielsen, E. E. Ferguson, R. L. Hudson, D. C. Smith, R. L. Collins, and L.Mikkelsen, ibid., p. 1457, 1464, 1470, 1475, 1727, 1731, 1736.6 8 F. F. Cleveland, A. G. Meister, F. L. Voelz, C. E. Decker, R. B. Bernstein, S. I.Miller, A. Weber, J. P. Zietlow, and J. E. Lamport, ibid., p. 155, 189, 242, 930, 1778,1781, 1903. See also P. H. Lindenmeyer and P.A$. Harris, ibid., p. 408; H. D. Rix,ibid., p. 1077; S . R. Polo and M. K. Wilson, ibid., p. 1129; W. F. Edge11 and C. May,ibid., p. 1901.69 F. F. Cleveland, A. G. Meister, S. M. Ferigle, A. Weber, and C. E. Decker, ibid.,p. 90, 722, 1613. See also F. A. Miller and R. B. Hannan, ibid., p. 110; B. D. Saksena,R. E. Kagarise, and D. H. Rank, ibid., p. 1613 ; D. E. Mann, N. Acquista, and E. K.Plyler, ibid., p. 1949.7O H. Murata, ibid., p. 181 ; J. A. Hawkins and M. K. Wilson, ibid., p. 360; H.Murata and M. Kumada, ibid., p. 945; J. A. Hawkins, S. R. Polo, and M. K. Wilson,ibid., p. 1122; A. L. Smith, ibid., p. 1997; A. Monfils, Compt. rend., 1953, 236, 795.S. I. Mizushima, T. Shimanouchi, I. Nakagawa, A. Miyake, T. Miyazawa, I.Tchishima, and K.Kuratani, J , Chem. Phys., 1953, 21, 215, 815, 1411; B. Bak, L.Hansen, and J. Rastrup-Andersen, ibid., p. 1612; G. D. Buckley, J., 1953, 1325; L. A.Duncanson, J., 1952, 1753; G. J. Szasz and N. Sheppard, Trans. Fwaday Soc., 1953,49, 358; J. K. Brown and N. Sheppard, ibid., 1952, 48, 128.R. D. Johnson, R. J. Myers, and W. D. Gwinn, ibid., p. 1425LINNETT : MOLECULAR SPECTRA. 13The Raman spectrum of thionyl chloride 72 shows four displacements forwhich the scattered radiation is polarised. If the molecule were planar onlythree fundamentals should lead to polarised Raman lines, so the results showit to be non-planar. A similar approach has been made for selenium tetra-fluoride.73 It appears that the symmetry is C2u, and that the structure isderived from a trigonal bipyramid with one lone pair in an equatorial position.The Raman and infra-red spectra of ferrocene and ruthenocene have beenexamined 74 to obtain information about their structure.75 The smallnumber of lines and bands indicates that the molecules are highly symmetricaland that the interaction between the two rings is small.The Raman spectrum of gaseous ethylene has shown 76 that the partiallysymmetric Raman active C-H bond stretching vibration has a frequency of3108 cm.-l (cf.Plyler 77) and not 3272.78 Crawford et aE. have measured thethe infra-red spectrum of 1 : l-dideuteroethylene and have deduced all thegeneral valency force field-potential constants of ethylene. 79 As withethane 8o the bond-angle constants seem to be larger than all other interactionconstants.A thorough study has been made of the fundamental, overtone, and com-bination infra-red bands of hydrogen cyanide and deuterium cyanide.49The first-order anharmonic constants have been obtained and certain errorsin previous work corrected.No simple formula can reproduce accuratelyall the excited vibration levels as perturbations lead to irregularities whichhave been clearly observed.Bethel1 and Sheppard 81 have been able to identify certain infra-redbands in the spectra of the hydrates of nitric and perchloric acids as beingdue to H,O+. Another study of inorganic compounds has been that of theions UO,++, NpO,++, PuO,++, AmO,++, NpO,+, and Am02+.82 The singlycharged ions have a smaller antisymmetric valency vibration frequency thanthe doubly charged ions, indicating that the additional electron is antibond-ing.This vibration frequency is greater for PuO,++ than for the otherdoubly charged ions. Another inorganic application is the investigation ofthe Raman spectra of mixtures of the chlorides and iodides of silicon, tin, andgermanium, showing that mixed chloroiodides of these elements exist in themixtures.83 The infra-red spectra of the hexafluorides of sulphur, selenium,tellurium, tungsten, molybdenum, and uraniumJS4 and their Raman spectra,are consistent with these molecules’ being regular octahedra.Crawford and Dagg 85 have shown that, in an intense electric field, linesin the Q-branch for the fundamental vibrational transition of molecularhydrogen can be observed by infra-red absorption. Comparison with Raman72 C.A. McDowell, Trans. Faraday SOC., 1953, 49, 371.73 J. A. Rolfe, L. A. Woodward, and D. A. Long, ibid., p. 1388.74 E. R. Lippincott and R. D. Nelson, J . Chenz. Phys., 1953, 21, 1307.J. D. Dunitz and L. E. Orgel, Nature, 1953, 171, 121.75 H. H. Jaffe, J. Chem. Phys., 1953, 21, 156.7 6 B. P. Stoicheff, ibid., p. 755.7 8 D. H. Rank, E. R. Shull, and W. E. Axford, ibid., 1950, 18, 116.79 B. L. Crawford, J. E. Lancaster, and R. G. Inskeep, ibid., 1953, 21, 678.81 D. E. Bethel1 and N. Sheppard, ibid., 1953, 21, 1421.8 2 L. H. Jones and R. A. Penneman, ibid., p. 542.83 M. L. Delwaulle, M. B. Busset, and M. Delhaye, J . Amev. Chem. SOC., 1952, 74,5768.84 J.Gaunt, Trans. Faraday SOC., 1953, 49, 1122.8 5 M. F. Crawford and I. R. Dagg, Phys. Review, 1953, 91. 1569.See also7 7 E. K. Plyler, ibid., 1951, 19, 658.G. E. Hansen and D. M. Dennison, ibid., 1952, 20, 31314 GENERAL AND PHYSICAL CHEMISTRY.data suggests that there is a real discrepancy between the infra-red and Ramandata which increases with increasing rotational quantum number. Chisholmet aZ.86 have obtained infra-red absorption corresponding to the fundamentalvibration transition of hydrogen when other gases or hydrogen itself areadded at very high pressures (up to 1500 atmos.). Under these conditionsthe Q-branch is split.0 ther simple molecules that have been examined by infra-red and Ramanspectra are S2F10,87 Pb(CH,),, etc.,88 C(CD,),,89 and N,S,.90 Theoreticaltreatments and force-constant calculations have been made by Cra~ford,~lH i g g ~ , ~ ~ T~rkington?~ Thomas,94 Pitzer and G e l l e ~ , ~ ~ Heslop and Linnett ,96and othersg7Structure Determination.-A few examples of the application of vibra-tional spectra to the determination of structure will be presented.Flett 98 has examined thioamides containing the grouping *NH*CS* forevidence of the existence of the form *N:C(SH)-. He found a sharp band at3430 cm.-l and a broad one at 3000 cm.-l, which, because of its strength andby analogy with other molecules, was ascribed to the hydrogen bond:NH - * SC:.There were no bands near 2500 cm.-l indicating that S-Hbonds were not present. Goulden 99 has examined the quaternary methio-dides of NN-disubstituted thioamides, and from the decrease in the C-Nvibration frequency from 1611 in MeS*CPh:NPh to 1562 cm:l in(MeS*CPh:NPhMe) + concludes that there is a small contribution from thestructure MeSXPh-NPhMe. There is no frequency decrease when thesulphur atom is absent.Various studies have been made of organic phos-phorus compounds.lW Haszeldine lo1 has made a most interesting study ofaliphatic nitro-compounds, and the effect, on the cyano- and two nitro-groupstretching frequencies, of substituents on the carbon atom adjacent to thenitro-group. For example, he finds that halogen atoms and additionalnitro-groups lead to a rise in the antisymmetric and a fall in the symmetricnitro-group stretching frequencies.This implies a greater interaction be-tween the N-0 bonds. He has also examined the infra-red spectra of somefluorinated alcohols.lo2 Duncanson lo3 has shown that, in some cases, theketo-forms of some tetronic acids predominate in solution; and the effect ofstructure on the characteristic carbonyl frequency in about 130 quinonoidcompounds has been measured.104 Davison and Bates Io5 examined vinyl+86 D. A. Chisholm, J. C. F. Macdonaid, M. F. Crawford, and H. L. Welsh, Phys.8 7 D. Edelson, J . Awzer. Chem. SOC., 1952, 74, 262.88 E. R. Lippincott and M. C. Tobin, ibid., 1953, 75, 2436.89 E. R. Shull, T. S. Oakwood, and D. H. Rank, J . Chem. Phys., 1953, 21, 2024.99 E. R. Lippincott and M. C . Tobin, ibid., p. 1559.0 1 B. L. Crawford, ibid., p.1108.92 P. W. Higgs, ibid., p. 1131.94 W. J. 0. Thomas, Trans. Faraday SOC., 1953, 49, 855.g 5 K. S. Pitzer and E. Gelles, J . Chem. Phys., 1953, 21, 855.O 6 W. R. Heslop and J. W. Linnett, Trans. Favaday SOC., 1953, 49, 1262.9 7 J. S. Ziomek and C. €3. Mast, J . Chem. Phys., 1953, 21, 862; E. Ferguson, ibid..p. 886; J. C. Decius, ibid., p. 1121 ; C . Y . Pan and J. R. Nielsen, i b i d . , p. 1427.g8 R.I. St. C. Flett, J., 1953, 347.l o o M. Halman and S. Pinchas, J., 1953, 626; L. J . Bellamy and L. Beecher, J . ,1953, 728.lo2 Idem, e'bid., p. 1757.lo4 M. L. Josien, N. Fuson, J. M. Lebas, and T. M. Gregory, J . Chem. Phys., 1953,Review, 1952, 88, 957.O3 P. Torkington, ibid., p. 83.gg J. D. S. Goulden, J., 1953, 997.lo1 R. N. Haszeldine, J., 1953, 2525.lo3 L.A. Duncanson, J., 1953, 1207.lo5 W. H. T. Davison and G. R. Bates, J., 1953, 2607. 21, 331LINNETT : MOLECULAR SPECTRA. 15and isopropenyl compounds containing polar groups, considering shifts inthe characteristic C X bands. The characteristic frequencies of the azo- andisocyanate-groupings have been disccssed by Le Fcvre et d 1 0 6 and byDavison lo7 and Thomas.lO8N-substituted amides show a characteristic frequency at 1560 cm.-lwhich has been ascribed to C-N valency lo9 and also to N-H deformationvibrations.l1° Letaw and Gropp ll1 conclude from their examination of anumber of such compounds that the former assignment is correct, and suggestreasons for the absence of this band in NN-disubstituted amides. Kesslerand Sutherland have discussed the out-of-plane N-H deformation frequencyin the peptide link 112 (cf.Davies and Evans l13).The infra-red and Raman spectra of hydrocarbons have been discussed intwo valuable reviews by Sheppard and Simpson 114 (see also Stein andSutherland 115).Far Infra-red Spectroscopy.-Measurements have been extended furtherinto the infra-red by using new prism materials, grating instruments,l16 or byemploying residual rays.l17 These have been used to determine purerotational spectra and also low vibration frequencies. For example,O’Loane 117 observed vibration bands of C,O, at 192 crn.-l, PCl, at 190, andCH,*CHO at 120 and 245 cm:l Hansler and Oetjen33 observed purerotation spectra between 70 and 250 cm.-l Pitzer and Hollenberg 11*examined the spectrum of CH3*CC1, from 130 to 430 cm.-l, observing bands at239 and 344 together with a sequence of absorption peaks at 135,154, and 172which seemed to be related to another series at 565, 548, and 533 cm.-lThey ascribed the last six bands to transitions involving various levels of thetorsional vibration combined with the 0 + 1 transition of a fundamental offrequency 351 cm.-l and concluded that the successive levels of the torsionalvibration lay at 214, 412, and 591 cm.-l (transitions suggested were:351 - 214= 137;351 + 214 = 565;351 + 214- 412 = 153;351 + 412 - 214 = 549;351 + 412 - 591 = 172;351 + 591 - 412 = 530).The successive levels of the torsional vibration were interpreted in terms of apotential functionV(+) = 4V3(l - cos 34) + $V6(l - cos 64).The levels observed lead to V3 = 1017 cm.-l (2910 cals./mole) and v6 = 19.9cm.-l (57 cals./mole).So the height of the barrier is 2967 cals. and theminimum narrower and the maximum broader than for a function withv6 = 0.loti R. J. W. Le Fbvre, M. F. O’Dwyer, and R. L. Werner, Chenz. a;zd I n d . , 1953,378.lo’ W. H. T. Davison, J., 1953. 3712.lo8 W. J. 0. Thomas, Chem. and Ind., 1953, 567.log H. Lenormant, Ann. Chim., 1950, 5, 459.110 R. E. Richards and H. W. Thompson, J . , 1947, 1248.ll1 H. Letaw and A. H. Gropp, J . Chem. Phys., 1953, 21, 1621.112 H. K. Kessler and G. B. B. M. Sutherland, ibid., p. 570.llS M. Davies and J. C. Evans, J., 1953, 480.114 N. Sheppard and D. M. Simpson, Quart.Reviews, 1952, 6, 1 ; 1953, 7, 19.115 R. S. Stein and G. B. B. M. Sutherland, J . Chem. Phys.. 1953, 21, 370.116 C. R. Bohn, N. K. Freeman, W. D. Gwinn, J. L. Hollenberg, and K. S. Pitzer,ibid., p. 719; R. A. Oetjen, W. H. Haynie, W. M. Ward, R. L. Hansler, H. E. Schwau-wecker, and E. E. Bell, J . Opt. SOC. Amer., 1952, 42, 559.117 J. K. O’Loane, J . Chem. Phys., 1953, 21, 669.11* K. S. Pitzer and J. L. Hollenberg, J . Amer. Chem. SOC., 1953, 75, 221916 GENERAL AND PHYSICAL CHEMISTRY.There is no doubt that a study of the region 7 0 4 0 0 cm? would be mostvaluable.Intensities of Infra-red Bands.-The present paragraphs supplement lastyear’s section, under the same title.Penner and Weber 119 have measured the intensities of the fundamentaland first overtone bands of nitric oxide, hydrogen chloride, and hydrogenbromide, the pressure-broadening technique being used.120 Their measuredintensity for the fundamental of nitric oxide is about half that observed byother workers. The value for the first overtone agrees with that given byCrawford and Dinsmore 121 however. With hydrogen chloride there is muchbetter agreement for the fundamental,122 though Penner and Weber do notagree with Dunham’s value for the 0 ~ e r t o n e . l ~ ~ These results show somedisagreement even for the measured relative intensities (cf. results for car-bony1 sulphide 12*).From the intensities of fundamental and overtone, Penner and Weber 119find for hydrogen chloride :(where represents the electric moment), demonstrating that when theresults for two bands are combined, there are alternative sets of results whichsatisfy the data, because the intensity of a band is dependent only on themagnitude and not on the sign of the moment change.It is often impossibleto choose between these alternative sets.Schatz and Hornig l 2 5 have determined the intensities of the two infra-redbands each of carbon tetrafluoride, silicon tetrafluoride, and sulphur hexa-fluoride. Graphs presented show that the deduced values for the bondmoment, p’, and its derivative with respect to bond length, dp’/dr (cf. ref. l),are very dependent on the particular potential-energy function selected. Innone of these molecules can a unique force field be derived from the fre-quencies. So there is uncertainty in the deduced bond-moment data becauseof uncertainty in our knowledge of the potential constants.This demon-strates a difficulty often encountered in making reliable use of intensity data.Schatz and Hornig list sets of most likely p’ and dp’/dr for these threemolecules. For example they give for carbon tetrafluoride p‘ = 1-12 D,and dp’/dr = 4.88 D/L% (a less likely set is 2.36 D and 3.35 D/A). They com-pare their value for dp‘ldr with that of 4.70 for the C-F bond in methylfluoride.By examining band intensities in hydrogen cyanide and deuteriumcyanide, Hyde and Hornig 127 obtained values for the C-H and C-N bondmoments, assuming these to remain constant and directed from atom to atomduring the bending vibration. The vector sum of these bond moments11° S.S. Penner and D. Weber, J . Chem. Phys., 1953, 21, 649.lZo E. B. Wilson and A. J. Wells, ibid., 1946, 14, 578.121 B. L. Crawford and H. L. Dinsmore, ibid., 1950, 18, 983, 1682.122 D. G. Bourgin, Phys. Review, 1927, 29, 794; 1928, 32, 237; R. Rollefson and A.Rollefson, ibid., 1935, 48, 779. la3 J. L. Dunham, ibid., 1929, 34, 438; 1930, 35, 1347.12* D. 2. Robinson, J . Chem. Phys., 1951, 19, 881; H. J. Callomon, D. C. McKean,and H. W. Thompson, Proc. Roy. Sic., 1951, A , 208, 341.lz5 P. N. Schatz and D. F. Hornig, J . Chem. Phys., 1953, 21, 1516.lZ6 G. M. Barrow and D. C. McKean, Proc. Roy. Soc., 1952, A , 213, 27.12’ G. E. Hyde and D. F. Hornig, J . Chem. Phys., 1952, 20, 977LINNETT MOLECULAR SPECTRA.17agreed quite well with the observed moment of hydrogen cyanide. However,in other molecules (e.g., the methyl halides) the agreement is not good.128This, along with other results, makes it doubtful whether the approximationof additive bond moments is a goodThe above examples demonstrate some of the difficulties arising in thedetailed interpretation of band intensities in simple molecules. Consequentlysome workers have felt that more progress could be made by examiningintensity variations in series of molecules. Richards and Burton 130 studiedthe bands due to N-H and C=O vibrations. They found that the intensityof the characteristic C=O band near 1700 cm.-l increased in the series:aldehyde, ketone, acid chloride, ester, and amide. The intensity of thecarbonyl bond in a series of molecules in the vapour state and in solutionhas since been studied by Barrow.131 He ascribes increased intensities overthose in simple aldehydes and ketones to the effects of conjugation (cf.Fraserand Price 132) and obtains a quantitative correlation of increase in intensitywith the resonance energy. Liddel, Wulf, and Hendriks 133 studied N-H andO-H bands, Fox and Martin 134 C-H, and Francis135 C-H bands (cf.Mecke 136).There seems little doubt that both types of approach are valuable.A valuable application of intensity measurements has been made to thedetermination of structure in steroids.137 had given a numberof relationships which enabled changes in the carbonyl characteristic fre-quency to be used in assigning structures in these molecules ; but ambiguitiesarose when frequencies of two groupings were very nearly the same.In suchcases changes in integrated band intensity, the determination of which hasbeen considered by Ram~ay,13~ can sometimes be used to differentiate be-tween different side-chain carbonyl groupings. The intensity may vary by afactor of four, and systematic changes occur when the carbonyl group isconjugated. For ring carbonyls the intensity varies only slightly withposition so, for these, integrated band intensities may be used to determinethe number of them.Whiffen 140 examined the effect of solvent on the intensity of the 760ern? band of chloroform. The integrated area is approximately indepen-dent of the solvent ( * l O ~ o ) , but the peak height and width at half-heightvary much more (3 40%).This is important for the use of such measure-ments for structural determinations.Herman and S h ~ l e r , l ~ ~ and Heaps and Herzberg 142 have obtained ex-12* I am grateful to A. V. Golton for discussions of these topics.120 A. M. Thorndike, J . Chem. Phys., 1947, 15, 868.130 R. E. Richards and W. R. Burton, Trans. Faraday SOC., 1949, 45, 874.131 G. M. Barrow, J . Chem. Phys., 1953, 21, 2008.132 R. D. B. Fraser and W. C. Price, Nature, 1952, 170, 490.133 U. Liddel, 0. R. Wulf, and S. B. Hendriks, J . Autzer. Chem. SOC., 1933, 55, 3574;134 J . J. Fox and A. E. Martin, Proc. Roy. SOC., 1937, A, 162, 417.136 S. A. Francis, J . Chem. Phys., 1950, 18, 861.136 R.Mecke, ibid.. 1952, 20, 1935.13' R. N. Jones, I). A. Ramsay, D. S. Keir, and K. Dobriner, J . Awzer. Chenz. SOC.,lS8 R. N. Jones, P. Humphries, and K. Dobriner, ibid., 1950, 72, 956.130 D. A. Ramsay, ibid., 1952, 74, 72.140 D. H. Whiffen, Trans. Faraday SOC., 1953, 49, 878.142 H. S. Heaps and G. Herzberg, 2. Physik, 1052, 133, 48.Jones et1953, 57, 1464; 1936, 58, 2287.1952, 74, 80.R. C . Herman and K. E. Shuler, J . Chern. Phys., 1053, 21, 37318 GENERAL AND PHYSICAL CHEMISTRY.pressions for transition probabilities, continuing the work of Dunham,l23R ~ s e n t h a l , ~ ~ ~ and Crawford and Dinsmore.121Intensities of Raman Lines.-The study of intensities in the vibrationalRaman effect is more difficult, both experimentally and theoretically, thanthat of infra-red intensities. Theoretically this is because polarisability is atensor and six quantities are required, in the absence of symmetry, to specifyfully its change during a vibration.In general the dipole moment, being avector, can be specified by three quantities, though again symmetry mayreduce this number. A consequence of this greater complexity is thatassumptions regarding the cause of polarisability changes have to be intro-duced at an earlier stage in the theory of Raman intensities than in that ofinfra-red intensities.Long,144 in a paper on intensities in Raman spectra, discusses a bond-polarisability theory according to which the polarisability associated witheach bond can be specified by four quantities : the equilibrium longitudinaland transverse polarisabilities, and the changes in these with length.I t isalso assumed that the bond polarisabilities can be added vectorially.Wolkenstein 145 applied this successfully to a number of halogen derivativesof methane, supposing that the bond properties could be transferred fromone molecule to another. An alternative hypothesis was suggested byCabannes and Rousset 146 who regarded the atoms as centres of constantpolarisability and ascribed changes that occurred during vibrations tochanging interactions between them. Bhagavantam 14’ treated hydrogen,nitrogen, oxygen, and chlorine according to this model ; success was greatestfor chlorine, in which most of the electrons are in lone pairs, and least inhydrogen where all electrons are bonding.Rao 148 treated carbon tetra-chloride similarly [k., as C4’ (Cl-)4]. Assuming the polarisability of C4+ tobe zero, he obtained a derived polarisability for the symmetric vibration closeto the experimental value. Woodward and Long 149 showed that similarcalculations for silicon tetrachloride, stannic chloride, carbon tetrabromide,silicon tetrabromide, and stannic bromide were unsuccessful. Matossi 150employed a similar approach but found it necessary to suppose that theatomic polarisabilities themselves vary during the distortions. A similarapproach has been made by Heslop and L i ~ ~ n e t t , ~ ~ who treat boron tri-fluoride as B3+(F-),, it being supposed that the polarisability resides solelyin the fluoride ions.They are able to account for the observed relativeintensities, a constant polarisability for the fluoride ion being used, but thededuced depolarisation factor is much greater than that to be expectedexperimentally by analogy with boron trichloride. So it appears that theCabannes and Rousset approach is only partially successful but, nevertheless,that it is worth further study. On the other hand the most successful treat-143 J. E. Rosenthal, Proc. Nat. Acad. Sci., 1935, 21, 281.144 D. A. Long, Proc. Roy. Soc., 1935, A , 217, 203.145 M. Wolkenstein, Acta Physicochenz. U.R.S.S., 1945, 20, 161, 174, 525, 544, 835,883; J . Exp. Theor. Phys. U.S.S.R.. 1948, 18, 138; Conzpt. rend. Acad. Sci. U.R.S.S.,1941, 32, 185; J . Phys. U.S.S.R., 1945, 9, 101, 326.146 J.Cabannes and A. Rousset, J . Phys. Radium, 1940, 1, [viii], 138, 155.14’ S. Bhagavantam, “ Scattering of Light and the Raman Effect,” Chem. Publ.Co. Inc., New York, 1942, p. 103.lo8 B. P. Rao, Proc. Indian Acad. Sci., 1940, 11. 1.149 L. A. Woodward and D. A. Long, see ref. 144.lS3 F. Matossi, J. Chem. Pliys., 1951, 19, 1007LINNETT MOLECULAR SPECTRA. 19ment of a wide range of molecules is that of the halogenomethanes byW ~ l k e n s t e i n , ~ ~ ~ who used a bond-polarisability theory. 151Further experimental results are needed in this most interesting field.It may then be possible to choose between the different hypotheses.Quadrupole-coupling Coefficients.-The quadrupole-coupling coeficients,obtained by micro-wave spectroscopy, allow the determination of the electricfield gradient at a nucleus having a known quadrupole moment.This fieldgradient is caused by the asymmetry of the electron cloud, and so thesemeasurements provide information about the electron distribution. Thishas often been interpreted in terms of hybridised orbitals. References topapers describing such measurements were given in 1952.1 During 1953further results have been published. Klein and Nethercot 64 have concludedthat in deuterium iodide, in which the electronegativities indicate that thereis 5% ionic character, there is also 15-20% s-hybridisation in the bondingorbital of the iodine atom. Sheridan and Gordy 23 have concluded that therewas 6.6% double-bond character in the C-C1 bond of chlorotrifluoromethane.From the micro-wave spectrum of arsenic trifluoride Kisliuk and Geschtvind 152obtain one moment of inertia and a quadrupole-coupling coefficient.Bycombining these, interpreting the latter in terms of sfi-hybridisation, anddrawing analogies with arsenic trichloride they deduce an approximate valuefor the FAsF angle. Robinson 53 has studied carbonyl chloride whichcontains two chlorine nuclei, and in C035C137C1 two different chlorine nuclei.The theory of this has been examined by Robinson and Corn~e11.l~~ Theresults indicate that the electron distribution is not cylindrically symmetricabout the C-C1 bond, but that it extends to a greater degree out of the planeof the molecule. This might be due to (a) some x bonding in the C-C1 bond;(b) a distortion of the closed shells of the chlorine atom; or (c) a distortionof the charge distribution in the C-C1 bond by mutual repulsion.It is notpossible to differentiate between these, but Robinson concludes that perhapsthe first is the most important (cf. vinyl chloride). Burrus and Gordy 65have studied H:% and state that 3% s-character is necessary to account forthe angle of 92", but that this would not account for the observed splitting.They suggest that the two results could be simultaneously explained bysupposing that the bonding orbitals are sfid-hybrids (15% 2s and 15% 3 4 ,while one non-bonding orbital is pure p and the other is 30% p . From themicro-wave absorption spectrum of oxygen, Miller et aZ.154 conclude thatthe unpaired electrons are in orbitals that are primarily fix, but haveapproximately 2.5% s-character.It seems that we should be cautious for the present in interpreting themeasured quadrupole-coupling coefficients in the above simple terms ofhybridisation changes.The field gradient at the nucleus must be affectedconsiderably by a small degree of asymmetry in the electron cloud near thenucleus. It is impossible to be sure that such asymmetry does not outweigheffects farther out on which, say, bond angles are dependent. Also thesymmetry of bonding and lone-pair orbitals may be affected by inter-electron repulsion and exclusion effects. The justification for linking bondA151 K. G. Denbigh, Trans. Faraduy SOL, 1940, 36, 936.lS2 P. Kisliuk and S.Geschwind, J . Chem. Phys., 1953, 21, 828.153 G. W. Robinson and C. D. Cornwell, ibid., p. 2436.154 S. L. Miller, C. H. Townes, and M. Kotani, Phys. Review, 1953, 90, 54220 GENERAL AND PHYSICAL CHEMISTRY.angles with quadrupole-coupling coefficients in deducing extents of hybrid-isation is, therefore, uncertain.Excited States of Polyatomic Molecules.-Ingold et a,?. 155 studied in detailan ultra-violet band system of benzene and obtained information about theupper electronic state of benzene. The forces in this upper state were com-pared with those previously known for the lower. Ingold and King 156 havenow made a detailed study of a band system of acetylene (both acetyleneand dideuteroacetylene were used). Their most important conclusion isthat the molecule is not linear in the upper state but has a centrally sym-metric trans-configuration. The evidence for this lies in both the rotationaland the vibrational structure of the system.For example, the ground-state progression appearing strongly is that associated with the centrallysymmetric bending vibration which is Raman-active. This, on the abovehypothesis, has the same symmetry as the molecule in its upper state andwould therefore be expected to appear strongly. Likewise the frequenciesobserved for the upper state can be reasonably ascribed to the symmetricvibrations of such a bent molecule. Since symmetric vibrations are expectedto appear on excitation this again supports the bent form. The rotationalstructure yields moments of inertia for the upper state, one being the sumof the other two, showing that the molecule is planar.The most likelydimensions consistent with these two independent moments of inertia seemto be r a = 1.383, ~ C H = 1.08 A, and the CCH angle 120.2". Ingold andKing point to the similarity between these figures and those for benzene,and suggest a three-electron C-C bond. The vibration frequencies forthe symmetric vibration of the excited state of acetylene are 1049, 1380,and ca. 3000 cmrl, and of dideuteroacetylene 844, 1310, and 2215 cm.-l.From these values it is deduced that the C-C force constant is 7.2 x lo5,close to that found for benzene, and between that of the single (4.5 x lo5) 15'and that of the double bond (9.8 x 105).158 Hence Ingold and King favouran electronic structure for the excited state involving a doubly-occupiedG and a singly-occupied x bonding orbital.It is noteworthy that the excitedstate has a larger bending frequency than the ground state.159Duchesne and Burnelle l60 have discussed the molecular vibrations of theground and excited states of Clo,, c10,-, SO,, CF,, and C6H6. In sulphurdioxide they find that the bond force constant falls from about 10 x lo5 inthe ground state to about 4-3 x 105 in the excited state. This suggeststhat a bond whose strength corresponds to a double bond is, on excitation,replaced by one whose character corresponds more to that of a single one.Delsemme and Duchesne have also considered difluorobenzene, andDuchesne thiocarbonyl chloride.16, Duchesne, and also Duchesne andBurnelle, make certain tentative conclusions about the cross-term potentialconstants in the excited states.A155 F.M. Garforth, C. K. Ingold, and H. G. Poole, J., 1948, 406 417, 427, 433, 440,156 C. K. Ingold and G. W. King, J., 1953, 2702, 2704, 2708, 2725, 2745.15' F. Stitt, J . Chew. Phys., 1939, 7, 1115.158 J. W. Linnett, Quart. Reviews. 1947, 1, 73.159 J. W. Linnett, D. F. Heath, and P. J. Wheatley, Trans. Furuduy S ~ C . , 1949, 45,161 A. Delsemme and J. Duchesne, Compt. rend., 1952, 234, 612.162 J. Duchesne, J . Chem. Phys., 1953, 21, 548.445, 456, 461, 475, 483, 491, 508.833. 160 J. Duchesne and L. Burnelle, J . Chew. Phys., 1953, 21, 2005LINNETT : MOLECULAR SPECTRA. 21Walsh,163 in an interesting series of ten papers under the general title,'' The Electronic Orbitals, Shapes, and Spectra of Polyatomic Molecules,''has considered the electronic orbitals occurring in various molecular systems(e.g., AH, AB,, BAC, HAB, HAAH, AH,, H,AB, and the specific moleculesacetaldehyde, methyl iodide, ethylene, and benzene), also the way in whichthese orbitals may be expected to be affected by molecular shape, andthe possible transitions between the various orbitals.For example, for AH,a correlation graph plots the energies of the various orbitals against the inter-bond angle from 90" to 180". It is concluded that orbitals of lower energyare more stable in the linear form, while the higher ones have a lower energywhen the molecular angle is 90'.Consequently molecules like berylliumhydride, BeH,, with few valency electrons, would be expected, in the groundstate, to be linear; while those with more electrons, such as NH, and OH,,with electrons in the orbitals of higher energy, which favour an inter-bondangle closer to go", should be non-linear. From the changes in the occu-pation of the orbitals that occur on excitation, and the correlation diagram,Walsh draws certain conclusions regarding changes of shape that occur onelectronic excitation. For example, he concludes that the longest wave-length system of NH, should involve an excited state with an inter-bondangle greater than, but a bond length about equal to, that in the groundstate, Walsh draws attention to the decrease in angle in AB, molecules asthe number of valency electrons increases from 16 to 20.For example,carbon dioxide with 16 is linear ; nitrogen dioxide with 17 has an interbondangle of 130"; ozone with 18, 116"; chlorine dioxide with 19, 1164"; andfluorine oxide with 20, 101". These changes are explained by the correlationdiagram for AB,. The trihalide ions, with 22 valency electrons, are againlinear because in AB, molecules the highest molecular orbitals favour alinear structure. Walsh has discussed the electron transitions observed orexpected for the various molecular types. For example, with hydrogencyanide two band systems are observed near 1900 and 1450 A. The structureof the former suggests an excited-state vibration frequency of 450 cm.-l.This is probably a bending vibration frequency and indicates that the trans-ition is to a bent upper state.The excited-state frequency appearing in the1450 A system is about 900 cm.-l, which Walsh concludes is due to a weakenedC-N bond in a linear upper state. In the series the spectra of HCO, HO,,C,H,, H,CO, H,O, etc. are discussed.Sutcliffe and Walsh 164 have obtained the absorption spectrum of allenein the vacuum ultra-violet. This extends the work of Price, Teegan, andWalsh 165 on keten.Diatomic Molecules.-The dissociation energy of fluorine now seems tobe definitely fixed a little below 40 kcals./mole. Doescher,166 from PVTmeasurements on the gas, obtained the value of 37.4; while Wise,167 byan effusion method, obtained 39-9.Gilles and Margrave,168 using a methodsimilar to Doescher's, conclude that the best value is 36 3. Barrow andCaunt ,169 from extensive measurements of the ultra-violet spectra and163 A. D. Walsh, J., 1953, 2260, 2266, 2288, 2296, 2301, 2306, 2318, 2321, 2325, 2330.16d L. H. Sutcliffe and A. D. Walsh, J., 1952, 899.165 W. C. Price, J . P. Teegan, and A. D. Walsh, J., 1951, 920.166 R. N. Doescher, J. Chern. Phys., 1951, 19, 1070; 1952, 20, 330.16' H. Wise, ibid., p. 927.lB9 R. F. Barrow and A. D. Caunt, Proc. Roy. Soc., 1953, A , 219, 120. 368 P. W. Gilles and J. L. Margrave, ibid., 1953,21,38122 GENERAL AND PHYSICAL CHEMISTRY.dissociation energies of the alkali-metal halides, conclude that the best valueis 37.6 5 1.6. This is in the middle of the range suggested by Evans etObservations have been made on the ultra-violet spectra of AlF,171GaF, and InF.17, The ground-state dissociation energies of the last twocan be deduced easily, but the case of AlF is difficult.Rowlinson and Barrowhave studied the A l I I - XIZ+ emission system. A short extrapolation ofthe vibrational levels of the lll upper state leads to a ground-state dissoci-ation energy (Do") of 7.2 & 0.3 ev. Levels are observed in this lrI state upto such an energy that Do'' must be greater than 6-51 ev. However, thermo-dynamic data lead to a value of 6.3, (147 kcals.) for the dissociation energy.There seems to be little doubt, therefore, that in A1F there is a maximum inthe potential-energy curve. In the case of Sn0,173 however, the spectro-scopic and thermodynamic values for the dissociation energy agree.Otherdiatomic molecules whose ultra-violet spectra have been examined recentlyinclude I3Cl6O 32 , N 2, 174 CSe,175 NO,176 HBr+,177 C12+,17'3 and SnS.179Attempts have been made by Pillow I8O and by Wu lS1 to account forthe relative intensities of the various bands in an ultra-violet system. Pillowused a method which involves displacing and altering the scale of the simpleharmonic oscillator wave functions, which are available. Wu has given anapproximate method for employing the Morse function. Both have beenapplied to the second negative system of 0,+(A2111, - X 2 n g ) . Both treat-ments agree, in the general pattern, with the observed intensities,ls2 butthere are differences in detail. Pillow 183 also calculated the band intensitiesin the Herzberg system of oxygen, observed by Broida and Gaydon in anoxygen after-glow.The agreement between theory and experiment wasquite good. She has also treated the CN violet system observed in acarbon arc.lS4 One set of results leads to a vibrational temperature in theexcited-state molecules of 8000" 500" K, while another set leads to 6200" K.In this case the intensity of all the observed bands did not fit accuratelyinto the theoretical pattern.Flash Photo1ysis.-More investigations have used the technique of flashp h o t o l y s i ~ . ~ ~ ~ For example, the absorption spectra of the free radicalsproduced during combustion of acetylene have been photographed.ls6 Inaddition to the usual systems, the Mulliken bands arising from the lC-stateof C, have been observed, and also a line at 4051 A.which may be identicalwith that observed in emission by Swings et aZ.lS7 and by Herzberg,lss andl70 M. G. Evans, E. Warhurst, and E. Whittle, J . , 1950, 1524.171 H. C. Rowlinson and R. F. Barrow, Proc. Phys. soc., 1953, A , 66, 437, 771.172 D. Welti and R. F. Barrow, ibid., 1952, A , 65, 629.173 G. Drummond and R. F. Barrow, ibid., p. 148.174 R. E. Worley, Phys. Review. 1953, 89, 863.175 R. K. Laird and R. F. Barrow, Proc. Phys. soc., 1953, A , 66, 836.176 L. H. Sutcliffe and A. D. Walsh, ibid., p. 217.177 R. F. Barrow and A. D. Caunt, ibid., p. 617. 178 H. G. Howell, ibid., p. 759.170 R. F. Barrow, G.Drummond, and H. C. Rowlinson, ibid., p. 885.180 M. Pillow, ibid., 1949, A , 62, 237; 1950, A , 63, 940; 1951, A , 64, 772; 1952,181 T.-Y. Wu, ibid., 1952, A , 65, 859.lS2 M. Feast, ibid., 1950, A , 63, 557. lS3 M. Pillow, ibid., 1953, A , 66, 733, 1064.lS4 M. Pillow, ibid., p. 737.lS5 R. G. W. Norrish and G. Porter, Proc. Roy. Soc., 1952, A , 210, 439; G. Porter,ibid., 1950, A , 200, 284; R. G. W. Norrish, G. Porter, and B. A. Thrush, Nature, 1952,i89,5a2 ; i953,172,71. 188 I d e m , Proc. Roy. SOC., 1953, A , 216, 165.A , 65, 859.187 P. Swings, C . T. Elvey, and H. W. Babcock, Astrophys. J . , 1941, 94, 320.G. Herzberg, ibid., 1942, 96, 314LINNETT : MOLECULAR SPECTRA. 23ascribed to C,.1B9 The photochemical reaction between chlorine and oxygenhas been studied and the growth and decay of the C10 radical followedspectroscopically.l e O By the flash photolysis of several aldehydes Ramsayobtained bands which he has ascribed to CHO.lgl The band structuresuggests that the transition may be from a bent ground state to a linearexcited state. The dimensions given for the ground state are YCH = 1-08 -&0.02 A, rco = 1.19 0.01, and the HCO angle" 120" & 4". Continuousillumination 192 with a multiple-reflection cell,lg3 and flash p h o t o l y ~ i s , ~ ~ have been used to photograph the absorption bands of NH, and ND,.Flash photolysis has also been used to show the presence, after intenseillumination, of triplet states in molecules, such as anthracene, in solutionand to study their decay.lg5Flame Spectra.-Much work has been carried out recently on the emissionfrom flames.lg6 There has been great interest in, and discussion of, thespectroscopic measurement of rotational temperatures in flames, and in theabnormally high values sometimes obtained.Papers on this topic havebeen published by Gaydon and Wolfhard,lg7 by Penner,lg8 by Broida andhis co-workers,lg9 and by Shuler.200 Experiments have been carried out onatomic flames,201 on flames supported by fluorine,202 on diffusionon low-pressure and on flames at atmospheric pressure.205 Measure-ments have also been made on flames by a fast scanning infra-red spectro-meter.206AJ. W. L.lS9 A. E. Douglas, Astrophys. J . , 1951, 114, 466.leO G. Porter and F. J. Wright, Discuss.Fnvaday Soc., 1953, 14, 23.lS1 D. A. Ramsay, J . Chzm. Phys., 1953, 21, 960.lQ2 Idem, ibid., p. 165.lo3 J. U. White, J . Opt. SOC. Awzer., 1942, 32, 285; H. J. Bernstein and G. Herzberg,J . Chem. Phys., 1948, 16, 30.lS4 G. Herzberg and D. A. Ramsay, Discuss. Faraday SOC., 1953, 14, 11.Ig5 G. Porter and M. W. Windsor, J . Chem. Phys., 1953, 21, 2088.lg6 A. G. Gaydon, Quart. Revieus, 1950, 4, 1 ; A. G. Gaydon and H. G. Wolfhard," Flames, their Structure, Radiation and Temperature," Chapman and Hall, London,1953.lS7 A. G. Gaydon and H. G. Wolfhard, Proc. Roy. Soc., 1949, A , 199, 89; 1948, A ,194, 169; 1950, A , 210, 561, 570; 1951, A , 200, 118.lQ8 S. S. Penner, J . Chenz. Phys., 1951, 19, 272; 1952, 20, 507, 1175, 1341; 1953, 21,31, 686.lg9 H.P. Broida, ibid., 1951, 19, 1383; 1953, 21, 340; H. P. Broida and G. T. Lalos,ibid., 1952, 20, 1466; H. P. Broida and W. R. Kane, ibid., 1953, 21, 347; idem, Phys.Review, 1953, 89, 1053.2Ju I<. E. Shuler, J . C h e w Phys., 1950, 18, 1221; J . Phys. Chem., 1953, 57, 396.831 A. G. Gaydon and H. G. Wolfhard, Proc. Roy. SOC., 1953, A , 213, 366; H. P.Broida and A. G. Gaydon, ibid., 1953, A , 218, 60.2 J 2 R. A. Durie, Proc. Phys. SOC., 1950, A , 63, 1292; Proc. Roy. SOC., 1952, A , 211,110.203 H. G. Wolfhard and W. G. Parker, Proc. Phys. SOC., 1949, A , 62, 722; ibid., 1952,A , 65, 2.2d4 A. G. Gaydon and H. G. Wolfhard, Third Symposium on Combustion Flame andExplosion Phenomena, Williams and Wilkins, Baltimore, 1949, 504.205 P. Ausloos and A.van Tiggelen, Bull. SOC. chim. Belg., 1952, 61, 569; 1953, 62,223.276 P. J. Wheatley, E. R. Vincent, D. Rotenberg, and G. R. Cowan, J . Opt. SOC. Amer.,1951. 41, 665; G. R. Cowan, E. R. Vincent, and B. L. Crawford, ibid., 1953, 43, 710;H. F. White, G. R. Cowan, D. Rotenberg, and B. L. Crawford, J . Chem. Phys., 1953, 21,139924 GENERAL AND PHYSICAL CHEMISTRY.2. THERMOCHEMISTRY.Thermochemistry may be formally defined as that branch of chemicalthermodynamics which deals with changes in internal energy or heat contentassociated with chemical reactions. I t may lead to a knowledge of theheats of formation of compounds from their elements and, if the subsidiarydata are available, to heats of formation from gaseous atoms. The topiccan then be widened to include mean bond energies and bond dissociationenergies and the methods, thermochemical and otherwise, of measuring them.The main emphasis of the Report is on work published during 1953, butthe Reporter has tried to make one year stand for several by linking past andpresent work through the references.Bond Dissociation Energies and Mean Bond Energies.-The first expressionrefers to the energy required to break a particular bond in a molecule, asdistinct from a mean bond energy, which is the mean contribution from eachbond of a given type to the total heat of formation of the compound fromits constituent at0ms.l The dissociation energy of a bond can be obtaineddirectly from the energy involved in either the formation or the rupture ofthe bond in question, but apart from some work on hydrogen 2 and oxygen,3the direct determination of bond dissociation energies has been confined tobond-breaking reactions.The energy required to break the bond can besupplied in different forms, and the dissociation and ionization of moleculesby the impact of an electron beam of controlled energy have been studied byStevenson,4 who has extended his earlier work on hydrocarbons to includethe normal alkanes from C, to C,. It is assumed that in the case of the alkaneR-R’, if the ionization potential of R, I(R), is less than that of R’, then theappearance potential of the alkyl ion Ri, A(R+), corresponds to the processR-R’ + e- ---t R+ + R’ + 2e-. If R+ is formed through the excitation ofthe molecule to the dissociation limit of the lowest stable state of R-R’+, sothat the appearance potential contains neither excitation- nor kinetic-energy terms, then the appearance potential is related to the dissociationenergy of the bond joining R and R’ by the expressionA(R+) = I(R) + D(R-R’).There is evidence that this is a valid assumption.The expression can beextended to include C-H dissociation energies if the heat of the reaction,AH, of R’H + RR” = R”H + RR‘ is known. ThenThe following values have been obtained :D(PrLH) = 4.3 & 0-04 ev;I(Bus) + D(BuS-H) = 11.1, 5 0.1 ev;I(AmS) + D(AmS-H) = 10.8, 5 0.1 ev.Aal<,(R’+) - ARn*,(R+) D(R’-H) - D(R”-H) - AHD(BuLH) = 4.3, & 0.1 ev;1 H. A. Skinner and H. D. Springall, Nature, 1948, 162, 343; M.G. Evans and M.Szwarc, J . Chein. Phys., 1950, 18, 618.F. R. Bichowsky and L. C . Copeland, J . Anzer. Chenz. SOC., 1928, 50, 1315.W. H. Rodebush and S. M. Troxel, ibid., 1930, 52, 3467.D. P. Stevenson, J . Chew. Plzys., 1942, 10, 291; D. P. Stevenson and J. A. Hipple,J . Amer. Chern. SOC., 1942, 64, 1588, 2766; D. P. Stevenson, Discuss. Faraday SOL.,1951, 10, 35.4 D. P. Stevenson, Tffans. Faraday SOC., 1953, 49, 867CARSON : THERMOCHEMISTRY. 25A table of the best electron-impact values of D(R-H), where R changesfrom Me to But is also given, and the values I(Prn) = 7-9 & 0.1 ev andD(HS-H) = 4.0 & 0.1 ev are obtained by combining the above quantitieswith known data on chlorides and thiols. Branson and Smith have studiedthe molecules methane and methyl chloride, bromide, and iodide underelectron impact.They conclude that positively charged carbon ions appearin the process CH,X + e- ----t C+ + 3H + X + 2e- so that the appearancepotential can be expressed as A(C+) > D(C-3H-X) + I(C). The equalitysign is not used alone since the products may contain excess of energy.The second term in the expression allows the latent heat of vaporization ofcarbon to be evaluated, if the heat of formation of the undissociated com-pound is known ; this point is discussed later in the report. CH+ appears inthe process CH,X + e- _t CH+ + 2H + X + 2e- so that A(CH+) >D(CH-2H-X) + I(CH). The dissociation energy of the CH molecule,D(C-H), can then be expressed in terms of the two appearance potentialsA(C+) and A(CH+).The mean value for the substances considered isD(C-H) < 3.5 & 0-7 ev, which is in good agreement with the vahe obtainedspectros~opically.~ In determination of the dissociation energy D(Me-X),except in the case of methane, two processes were considered :(1) MeX +e- ----t Me+ + X + 2e- ;(2) MeX + e- ---t Me + X+ + 2e-A(Me+) = D(Me-X) + I(Me) and A(X+) = D(Me-X) + I(X).D(Me-H) < 4.2 & 0.2 ev;D(Me-Br) < 3.1 5 0.4 ev;which are in fair agreement with the figures quoted by Roberts and Skinner,*S ~ w a r c , ~ and McDowell and Cox.lOThe dissociation energies D(C-3H) > 11.2 ev and D(C-2H) < 7.4 evare also obtained and the four values involved in the stepwise dissociationof methane can be calculated.These values may be compared with theelectron-impact results of McDowell and Warren l1 and the theoreticalcalculations by Voge.12The ionization and dissociation of methylsiloxanes by electron impacthave been examined by Dibeler, Mohler, and Reese.13The energy required to break the bond may also be supplied in the formof heat, and the two methods that have been widely developed, the equili-brium method and the kinetic method, have been reviewed by S ~ w a r c . ~The kinetic method depends on the determination of the activation energyof the simple unimolecular dissociation which yields two atoms or radicalsthrough the breaking of a bond. If the reaction in the reverse direction has’ G. Herzberg, “ Molecular Spectra.I. Spectra of Diatomic Molecules.” 2nda J. S. Roberts and H. A. Skinner, Trans. Faraday Soc., 1949, 45, 339.givingThese two appearance potentials yield the following mean values :D(Me-I) < 2.3 3 0.2 ev ;D(Me-C1) < 3.4 & 0-5 ev,H. Branson and C. Smith, J . Amer. Chein. SOC., 1953, 75, 4133.Edn. Van Nostrand, New York, 1950.M. Szwarc, Chern. Reviews, 1950, 47, 75.lo C. A. McDowell and B. G. Cox, J . Chew,. Phys., 1952, 20, 1496.l1 C. A. McDowell and J. W. Warren, Discuss. Faraday SOC., 1951, 10, 53.l2 H. H. Voge, J . Chem. Phys., 1936, 4, 581 ; 1948, 16, 984.l3 V. H. Dibeler, F. L. Mohler, and R. M. Reese, J . Chem. Phys., 1953, 21, 18026 GENERAL AND PHYSICAL CHEMISTRY.no activation energy, then the activation energy for the dissociation processwill be equal to the bond dissociation energy.It seems very probable thatthe activation energy for the recombination of atoms or radicals is negligible,especially when steric hindrance cannot occur, and bond dissociation energiescalculated on this basis are in good agreement with values found by othermethods.Szwarc and his co-workers have started a study of the variations in bonddissociation energies of aromatic compounds. In the first paper l4 thepyrolysis of a series of aryl bromides is described. By use of the toluenecarrier-gas technique the primary, rate-determining step is shown to beAr-Br + Ar + Br, and the following dissociation energies are found :D(pheny1-Br) = 70.9 ; D(p-naphthyl-Br) = 70-0 ; D(a-naphthyl-Br) = 70.9 ;D(9-phenanthryl-Br) = 67.7 ; and D(9-anthryl-Br) = 65.6 kcal./mole.A11are subject to an uncertainty of A2 kcal./mole.Szwarc concludes that the C-Br dissociation energy does not seem tobe affected by the increase of the rI-electron system. On the other hand itdoes seem to be influenced by the fusion of a benzene ring in the ortho-position, and on the whole the C-Br bond dissociation energies in thearomatic compounds appear to be higher than in methyl bromide.The second paper l5 investigates the effect of substituents on the C-Brdissociation energy in a series of substituted bromobenzenes. The sub-stituents are F, C1, Br, CH,, C6H5, CN, and OH ; and the study was extendedto include broinopyridine and bromothiophen. The frequency factor wasassumed to be constant for the series of decompositions, and the difference indissociation energy D(Ph-Br) - D(Ph,,b.--Br) was obtained for 20 compounds.Only in the bromopyridines was there an increase in the C-Br dissociationenergy.The most marked decrease was due to the hydroxy-substituent andthe effect was much the same for ortho-, meia-, and para-compounds. Replace-ment of hydrogen by halogen, methyl, phenyl, or nitrile groups has only aslight effect, which is enhanced if the substitution is in the ortho-position,the increase depending on the bulkiness of the group.Chilton and Gowenlock 16 have examined the pyrolysis of diisopropyl-mercury in a flow system with nitrogen or a mixture of nitrogen and nitricoxide as carrier gas.The reaction is predominantly homogeneous andunimolecular. In view of the high value of the frequency factor the meanactivation energy of 39.8 kcal./mole is considered to be the energy neces-sary to break both Hg-C bonds, and this agrees excellently with the valuequoted by Mortimer, Pritchard, and Skinner.17The heats of formation of dimethyl- and diethyl-mercury have beenredetermined in recent years 1 8 7 l9 and although the data can be used toevaluate the sum of the two Hg-C bond dissociation energies it cannot giveany information about the individual bond-breaking energies. From adetailed pyrolytic study of dimethyl- and diethyl-mercury Warhurst 2o and hisco-workers have now obtained this information. The rate-determining stepl4 M. Ladacki and M. Szwarc, Proc.Roy. Soc., 1953, A , 219, 341.15 M. Szwarc and D. Williams, ibid., p. 353.16 H. T. J. Chilton and B. G. Gowenlock, Trans. Faraday Soc., 1953, 49, 1451.17 C. T. Mortimer, H. 0. Pritchard, and H. A. Skinner, ibid., 1952, 48, 22C.18 K. Hartley, H. 0. Pritchard, and H. A. Skinner, ibid., 1950, 46, 1019 ; 1951,47,254.19 A. S. Carcon, E. M. Carson, and B. R. Wilmshurst, Nature, 1952, 170, 320.?O €3. G. Gowenlock, J. C. Polanyi, and E. Wsrhurst, Proc. Roy. Soc., 1953, A , 218,269CARSON : THERMOCHEMISTRY. 27was the breaking of the first Hg-C bond, and the activation energy wasassumed to be the dissociation energy of this bond, i.e., D(MeHg-Me) =51.5 & 2 kcal./mole. The data on the temperature coefficient of the diethyl-mercury pyrolysis were not complete but the dissociation energy was esti-mated to be D(EtHg-Et) = 41.5 kcal./mole.When combined with theheats of formation 189 l9 these figures confirm the belief that in the dissoci-ation of these mercury compounds into Hg + ZR, most of the energy isrequired to break the first Hg-C bond.The heats of formation of ethyl chloride and bromide and the C-halogenbond dissociation energies in these compounds have been determined by Lane,Linnett, and Oswin,21 using an equilibrium flow technique. The heat of thereaction C2H4 + HX = C,H,X, where X = C1 or Br, was calculated atvarious temperatures by combining the equilibrium constant a t that temp-erature with the calculated entropy change. The value of 3.7 kcal./moleobtained by Gordon and Giauque 22 for the barrier which restricts rotationin ethyl chloride was used, and with ethyl bromide the barrier height wasassumed to be about 4 kcal./mole. The heats of reaction corrected to 298" Klead to the following results: AHfO(EtC1, g) = - 26.7; AHfO(EtBr, g) =-15.3; D(Et-Cl) = 80.9; and D(Et-Br) = 67.2 kcal./mole, i f a value of97.5 kcal./mole is assumed for the dissociation energy of the first C-H bond 23in ethane.These values are in good agreement with those quoted in refs. 8,9,and 19. The authors also discuss the differences in the R-X dissociationenergies in a series of RX compounds where R is Me, Et, Prn, Pri, Bun, and But.For many years the dissociation energy of fluorine was thought to be63 kcal./mole but in a critical review Evans, Warhurst, and Whittle 23decided that a value in the region of 37 kcal./mole was probably correct, andthis figure has received support from subsequent work by Doescher 24 andWise.25 Wicke and Friz 26 have obtained the value D(F,) = 37.0. & 2 kcal./mole by exploding mixtures of hydrogen and fluorine in a steel sphere, themaximum pressure being corrected for impurities and for pressure oscillationsfollowing the explosion.ANfO(C1F) = 11.7 & 0.5 kcaI./mole was also found,and the method was checked by using mixtures of hydrogen and chlorine.Their value agrees excellently with that obtained by Barrow and Gaunt,,'who examined the fluctuation bands in the ultra-violet absorption spectrumand deduced the upper limits of the dissociation energies of the twelvepotassium, rubidium, and czsium halides.The dissociation energy of thegaseous halide is related to the dissociation energy of the halogen and onthis basis the mean value D(F,) = 37.6 5 1.6 kcal./mole was obtained. Alower value, D(F2) = 31.5 -+ 0.9 kcal./mole, was, however, found by Gillesand Margrave from a study of the pressure exerted by fluorine in a closedcopper system over the range 300-860" K.Farber and Darnel1 29 have used the Langmuir hot-wire technique todissociate hydrogen and nitrogen. The power necessary to heat the tungsten21 M. R. Lane, J. W. Linnett, and H. G. Oswin, Proc. Roy. SOC., 1935, A , 216, 361.22 J. Gordon and W. F. Giauque, J . Anzer. Chem. Soc., 1948, 70, 1506, 4277.24 R.N. Doescher, J . Chem. Phys., 1952, 20, 330; 1951, 19, 1070.25 H. Wise, zbzd., 1952,20,927.27 R. F. Barrow and A. D. Caunt, Proc. Roy. Soc., 1953, A , 219, 120.28 P. W. Gilles and J. L. Margrave, J . Chern. Phys., 1953, 21, 381.19 M. Farber and A. J. Darnell, ibid., p. 172.M. G. Evans, E. Warhurst, and E. Whittle, J., 1950, 1524.26 E. Wickeand H. Friz, 2. Elektrochem., 1953, 57, 928 GENERAL AND PHYSICAL CHEMISTRY.filament both in vacuo and in the gas is measured ; the total power differenceis divided between gas conduction and dissociation. The accommodationcoefficient is assumed to remain constant during the dissociation. Thedissociation energies so determined are D(H,) = 101 3 kcal./mole,D(N,) > 225 kcal./mole. The value for nitrogen is important since con-siderable controversy has surrounded 309 31 this dissociation energy, andvalues ranging from 170 to 250 kcal./mole have been quoted.Taylor andWijnen 32 claim to have eliminated the lower value in view of their failureto achieve the xenon-sensitized photosynthesis of ammonia by irradiatingmixtures of nitrogen and hydrogen with a xenon-resonance lamp which hadan energy equivalent of 194-5 kcal., the indication being that this energywas insufficient to break the N-N bond.Van Artsdalen and his collaborators, whose previous work33 in thekinetics of gas-phase bromination yielded much valuable data on bonddissociation energies, have now described 34 the thermal and photochemicalbromination of toluene. Substitution occurred in the side-chain, and theactivation energy of the overall reaction was assigned to the rate-determiningstep, Br + RH = R + HBr.The photochemical reaction was stronglyretarded by hydrogen bromide in the range 82-132" c, and this enabledthe activation energy of the back-reaction to be estimated. Using theknown value for D(H-Br), they obtain D(PhCH,-H) = 89.5 5 1.4 kcal./moleat 25" C, a figure which differs considerably from the value (77.5 kcal./mole)measured by S~warc.~5Skinner and his co-workers have described a series of reactions of phos-phorus, arsenic, and boron compounds. The heats of formation of phos-phorus trichloride, tribromide, oxychloride, and oxybromide were foundfrom their heats of hydr0lysis,3~ and the mean bond energies in phosphorustrichloride.and tribromide, D(P-Cl) = 77-9 kcal./mole, D(P-Br) = 63.4kcal./mole, and the P=O dissociation energy in phosphorus oxychlorideand oxybromide, D(Cl,P=O) = 121.8 kcal./mole, D(Br3P=O) = 119.3kcal./mole, can be deduced. These energies tend to confirm the view thatthe P-0 bonds resemble double rather than single bonds. There is as yetno reliable evaluation of the single P-0 link but a value has been reported 37for the heat of formation of P406, which leads to E(P-0) = 98-8 kcal./mole.D(F,P=O) is also known from work 38 on the direct oxidation of phosphorustrifluoride, and it is seen that there is a decrease in D(X,P=O) as X changesfrom F to C1 to Br. A simple steric explanation for this seems inadequatein view of the constancy of the P=O bond length in phosphorus oxychlorideand oxyfl~oride.~~The heats of formation 40 of trimethyl, triethyl and tripropyl arsenite30 A. G.Gaydon, " Dissociation Energies," Chapman and Hall, London, 1953.31 G. Gloclrler, J . Chenz. Phys., 1951, 19, 124.32 H. A. Taylor and N. H. J. Wijnen, ibid., 1953, 21, 233.33 E. R. van Artsdalen, ibid., 1942, 10, 653 ; C. B. Kistiakowsky and E. R. van Arts-dalen, ibid., 1944, 12, 469; H. C. Andersen and E. R. van Artsdalen, ibid., p. 479; E.I. Hormats and E. R. van Artsdalen, ibid., 1951,19, 778.34 H. R. Anderson, jun., H. A. Scheraga, and E. R. van Artsdalen, ibid., 1953,21, 1258.3 5 M. Szwarc, ibid., 1948, 16, 128. 36 H. A. Skinner and T. Charnley, J., 1953,450.a7 W. E. Koerner and F. Daniels, J .Chew. Phys., 1952, 20, 113.38 Fr. Ebel and E. Bretscher, Helv. Chim. A d a , 1929, 12, 450.39 W, Gordy, Q. Williams, and J. Sheridan, J. Chern. Phys., 1952, 20, 164.4O T. Charnley, C. T. Mortimer, and H. A. Skinner, J., 1953, 1181CARSON : THERMOCHEMISTRY. 29have been found from their heats of hydrolysis in 4~-sodium hydroxide, andthe following mean bond energies have been calculated, B(As-OMe) =62.64 2.3, n(As-OEt) = 64.45 & 1.4, and D(As-OPr) = 66.44 & 2.7kcal./mole. The calculations involve the heat of fonnation of the -ORradicals, and an account is given of the estimation of these quantities. TheD(As-OR) values are smaller than the D(As-0) value in As,O, and thedifference may lie in the hyperconjugation stabilization of the -OR radicals.The heat of the reaction between phenylarsine and iodine has beenmeasured 41 in carbon tetrachloride solution at 25" c, and the result enablesthe difference between the As-H and As-I mean bond energies in the com-pounds phenylarsine and phenyldi-iodoarsine to be expressed, AD -{:IF} =17.0 & 2-3 kcal./mole.This difference is in close agreement with thatbetween B(As-H) = 56.6 kcal./mole in arsine and AS-I) = 42.6 kcal./molein arsenic tri-iodide,,, and on the basis of this and earlier l8 results it issuggested that in mixed compounds of the general type R,MX,, where Mis the (m + n)-valent central atom, the values are transferable from theparent compounds when R = Ph and X = H or I, but that enhancementoccurs in one or more of theSkinner and Smith43 have found the heat of formation of liquid borontrichloride, AHfo(BC1,) = -103.0 -+ 1 kcal./mole, and Skinner and Tees44have studied calorimetrically a series of reactions involving tri-n-butyl-boron and the di-n-butylboron halides.By assuming that the mean B-CIbond energy in boron trichloride is the same as the dissociation energyD(Bu,B-Cl), the following dissociation energies can be calculated :D(Bu,B-OH) = 118.3 kcal./mole ; D(Bu,B-C1) = 93-9 kcal./mole ;values, when R = alkyl and X = halogen.D(Bu,B-Br) = 74-7 kcal./mole ; and D(Bu,B-I) = 56.2 kcal./mole.The absolute magnitude of these quantities may be in doubt, but thedifferences between them should be correct; also, since the value for thelatent heat of sublimation of boron is uncertain, the D and Dvalues quotedmay have to be increased by 14.6 kcal./mole.Thompson 45 has burnt the first four members of the linear poly(dimethy1-siloxane) series Me*[SiMe,*O];SiMe, in a combustion bomb and from theirheats of formation has calculated the mean bond energies B(Si-C) = 64kcal./mole and b(Si-0) = 117 kcal./mole.Drummond and Barrow 45a have estimated the dissociation energy ofgaseous beryllium oxide, basing their calculations on vapour-pressure,thermochemical, and spectroscopic data.The value obtained, 127 & 5kcal./mole, is lower than would be expected from a comparison between thedissociation energy and force constant of this molecule and those of theother oxides in this sub-group.Heats of Reaction.-When a compound is burnt in oxygen the productsof the combustion are usually simple molecules with well-known heats of41 C.T. Mortimer and H. A. Skinner, J . , 1953, 3189.43 H. A. Skinner and N. B. Smith, Trans. Faraday SOL, 1953, 49, 601.44 H. A. Skinner and T. F. S. Tees, J., 1953, 3378.45 R. Thompson, J . , 1953, 1908.450G. Drummond and R. F. Barrow, Trans. Famday SOC., 1953, 49, 599.42 Idem, J., 1952, 433130 GENERAL AND PHYSICAL CHEMISTRY.formation, and consequently this highly precise method is much used in findingheats of formation. The heats of formation of the following compounds havebeen found in this way, tetramethyltin and tetrameth~l-lead,~~ berylliumoxide,47 diazoaminobenzene, benzotriazole and 2-azidoethan01,~~ stannous andstannic hafnium oxide and nitride,50 and cerium Since 1934,in the University of Lund over 130 organic chloro- and 19 iodo-compoundshave been examined by combustion, the quartz-fibre technique being used ;128 of these values have now been corrected and published.51 Sunner 52has made a detailed study of the combustion of organo-sulphur compoundsin a rotating bomb.In his most recent paper 53 he suggests the useof thianthren as a secondary standard in bomb calorimetry for sulphurcompounds. Coops 54 and his co-workers have studied the heats of com-bustion of some 0- and P-tolylethylenes and phenylbutadienes, the veryprecise combustion calorimeter previously described 55 being used.A wide range of reactions, other than combustions, have been studiedduring the year.Koch and Cunningham 56 have continued their work onthe vapour-phase hydrolysis of the lanthanon halides and have obtainedheat and free-energy data for the hydrolysis of samarium and gadoliniumtrichlorides. The thermochemistry of the alkali and alkaline-earth metalsand halides in liquid ammonia has been examined by C o ~ l t e r . ~ ~ Jenkinsand Style 58 have obtained the heat of formation of bishydroxymethylperoxide by measuring its heat of reaction with sodium hydroxide; itsh2at of solution and latent heat of sublimation have also been measured.The heat of formation of thorium sesquisulphide 59 has been found from itsheat of solution, and the heats of solution of the cobaltous chloride hydratesin water and a number of oxygenated organic solvents have been measured.60Latimer and Jolly have determined calorimetrically at 25" c the heats ofthe six successive reactions between F- and A13+ to form AlF63-, and withHepler 62 they have calculated the heat of ionization of hydrogen fluorideby measuring the heat of solution of sodium fluoride in water and in aqueousperchloric acid. Mel, Jolly, and Latimer e3 have determined the heat offormation of the bromate ion by finding the heat of solution of potassiumbromate and the heats of reduction of potassium bromate with Br- and I-.4 6 E.R. Lippincott and M. C. Tobin, J . Amer. Chem. Soc., 1953, '95, 4141.4 7 L. A. Cosgrove and P. E. Snyder, ibid., p. 3102.49 G. L. Humphrey and C. J . O'Brien, ibid., p. 2805.5O G. L. Humphrey, ibid., p.2806.500 E. J. Huber and and C. E. Holley, jun., ibid., p. 5645.51 L. Smith, L. Bjellerup, S. Krook, and H. Westermark, Acta Chem. Scand., 1953,53 S. Sunner and B. Lundin, Actn Chew. Scand., 1953, 7, 1112.54 J . Coops, G. J. Hoijtink, Miss Th. J. E. Kramer, and hlise A. C. Faber, Rec. Trav.5 5 J. Coops, K. Van Nes, A. Kentie, J. W. Dienske, D. Mulder, and J. Smittenburg,5 6 C. W. Koch and B. B. Cunningham, J . Amer. Chem. Soc., 1953, 75, 796.5 7 L. V. Coulter, J . Phys. Chem., 1953, 57, 553.5 8 A. D. Jenkins and D. W. G. Style, J . , 1953, 2337.59 L. Eyring and E. F. Westrum, jun., J . Amer. Chem. Soc., 1953, 75, 4802.6O L. I. Katzin and J. R. Ferraro, ibid., p. 3821.61 W. M. Latimer and W. L. Jolly, ibid., p. 1548.62 L. G.Hepler, W. L. Jolly, and W. M. Latimer, ibid., p. 2809.63 H. C. Mel, W. L. Jolly, and W. M. Latimer, ibid., p. 3827.T. F. Fagley, E. Klein, and J . F. Albrecht, jun., ibid., p. 3104.7, 65.chim., 1953, 72, 765.ibid., 1947, 66, 113-176.5 2 S. Sunner, Thesis, Lund, 1949CARSON : THERMOCHEMISTRY. 31Andrianov and Pavlov 64 have investigated the heats of hydrolysis of com-pounds of the type RSiC1, and R,SiCl, where R = Me, Et, or Ph. Thesecompounds will form polymeric substances on hydrolysis with limited amountsof water, but hydrolyse to R,Si(OH), or RSi(OH), if a large excess of wateris used. Setton 65 has measured directly the heat liberated in the reactionnCs + nCO = (CsCO),, and Kroger 66 has calculated the heats of formationof ternary sodium calcium silicates from the oxides.Latent Heats.-It is unfortunate, in view of its importance in thermo-chemical calculations, that as yet there is no value for the latent heat ofsublimation of carbon, L(C), that will reconcile the conflicting data.Spring-all 67 and Gaydon 30 have reviewed the problem, and it is fair to say that inthe last few years the balance has definitely altered in favour of the " high "value (170 kcal./g.-atom).The direct methods for finding L(C) have been criticized on three countsthat (a) the accommodation coefficient is not unity, (b) the major part of thespecies evaporated is C, and (c) the carbon atoms may have to evaporateover a potential barrier. The last two criticisms have been answered byChupka and Inghram,68 who have used a mass spectrometer to identifythe products evaporated from a carbon filament.The relative amounts ofthe various products were measured and a retarding potential showed thatthe C+ ions produced by electron impact had only thermal energies. TheC atoms are produced in their ground state; the authors find thatL(C) = 178 -& 10 kcal./g.-atom. They hope later to investigate the questionof the accommodation coefficient. Margrave and Wieland 69 find that whencarbon tetrafluoride is thermally decomposed under equilibrium conditionsin a graphite furnace, CF, absorption bands are present at 1900" K and CFbands a t 2400" K. These results are in approximate agreement with thethermodynamic functions calculated by Potocki and Mann,'O if L(C) isassumed to be 170 kcal./g.-atom and f, which is related to the transitionprobability for the transition observed, is assumed to be for both CFand CF,.find that L(C) = 136 kcal./g.-atom, basingtheir calculation on the appearance potential of the C+ ion. It appears,however, that CH,+ is formed in the following way; CH,X + e- __tCH,+ + HX + 2e- and this at once casts doubt on the schemes envisagedfor the production of C+ and CH+. If H, or HX occurs as fragments inthese processes the values based on A(C+) and A(CH+) will have to be raised,but by how much is uncertain since the products may contain excitationalor excess of kinetic energy. The Knudsen method has been used to find thelatent heats of sublimation of tin,71 copper,', and gallium.73 A fluorescencemethod has been used by Stevens 74 to obtain vapour-pressure data andhence the heat of sublimation of anthracene and 9 : 10-diphenylanthracene.The heat of vaporization of hydrogen fluoride has been determined by JarryK. A.Andrianov and S. A. Pavlov, Doklady Akad. Naztk S.S.S.R., 1953, 88, 811.65 R. Setton, Compt. rend., 1953, 236, 1959.C. Kroger, Glastech. Ber., 1953, 2'7, 171.13' H. D. Springall, Research, 19.50, 3, 260.13* W. A. Chupka and M. G. Inghram, J . Chem. Phys., 1953, 21, 371.6Q T. L. Margrave and K. Weland, ibid., p. 1552.70 R. Potocki and D. Mann, Nut. Bur. Stand. Rpt., 1952, 1439.L. Brewer and R. F. Porter, J. Chem. Phys., 1953, 21, 2012.72 H. N. Hersh, J . Amer. Chem. Soc., 1953, 75, 1529.i3 R. Speiser and H.L. Johnston, ibid., p. 1469.Branson and Smith74 B. Stevens, J., 1953, 297332 GENERAL AND PHYSICAL CHEMISTRY.and Davis 75 from vapour-pressure data in the range 0-105" c. I t has beenpointed out 76 that both liquid and gaseous hydrogen fluoride may consistof polymers, (HF),, and it is not correct to assume that the liquid and thevapour consist of the same species and in the same proportions ; consequentlythe heat of vaporization has a meaning only when expressed on a weightbasis. Other work 77 on the fusion and vaporization of hydrogen fluoridehas been carried out by H u , White, and Johnston. Gottschal and Korvezee,'Susing their general vapour-pressure equation, have calculated a vapour-pressure curve for benzene, and obtained its heat of vaporization.Skinnerand Tees44 have quoted values for the heats of vaporization of tributyl-boron and butylboron halides.Thermodynamic Properties.-The compounds grouped together here havehad a wider range of thermodynamic properties determined. Diborane,between 13" K and its boiling point,79 and above its boiling point,*O 3-methylthiophen in the range 0-1000" K , ~ ~ thiacycZobutane,s2 2-methyl-propane-Z-thi01,~~ molybdenum trioxide at high temperature^,^^ andmercury. 85Theoretical.-In dimethylmercury the energy required to break the firstHg-C bond is much greater than that required to break the second20 andWarhurst et aZ.86 in considering this point suggest that the Hg-C bond inthe MeHg radical is predominantly a " polarization '' bond and that thechange from the bivalent to the zerovalent state of mercury occurs duringthe first dissociation. To bring the bond to the required strength someresonance with a bivalent covalent state of mercury is also envisaged.The relationship between mean bond energies and bond distances in thehydrocarbons has been discussed by G l ~ c k l e r , ~ ~ who assumes that it isparabolic between the C-C bond energies, B(CC), and distances, R(CC), andlinear between B ( C H ) and R ( C H ) .These assumptions when applied toacetylene, ethylene, ethane, methane, and diamond lead to the relation-ships : B(CC) = 1450.762 - 16440151 R(CC) + 491.936 R(CC)2, and B ( C H ) =Enough data are now known to give a reliable relationship betweenR(CC) and R ( C H ) , viz., R ( C H ) = 1.396 - 0.594 R(CC) + 0-261 R(CC)2,so that B ( C H ) = 98.104 - 0-075 B(CC) + [3.196 B(CC) - 246.04814.Theserelations are based on L ( C ) = 169.75 kcal./g.-atom, and similar expressionsbased on L ( C ) = 124.3 or 135.8 kcal./g.-atom are derived. The equationsare used in several cases to find how the atomic heat of formation is dis-tributed over the various bonds in the molecule. The following values in252.956 - 141.721 R ( C H ) .7 5 R. L. Jarry and W. Davis, jun., J . P h y s . Chem., 1953, 57, 600.7 6 J. H. Simons and A. S. Russell, ibid., 1939, 43, 901.7 7 J-H. Hu, D. White, and H. L. Johnston, J . Amer. Chern. Soc., 1953, 75, 1232.7 8 A. J. Gotfschal and Miss A. E. Korvezee, Rec. Tmv. chim., 1953, 72, 473.79 J.T. Clarke, E. B. Rifkin, and H. L. Johnston, J . A m e r . Chem. Soc., 1953, '75, 781.81 J. P. McCullough, S. Sunner, H. L. Finke, W. N. Hubbard, M. E. Gross, R. E.82 D. W. Scott, H. L. Finke, W. N. Hubbard, J. P. McCullough, C. Katz, M. E.83 I d e m , ibzd., p. 1818.85 R. H. Busey and W. F. Giauque, ibid., p. 806.8 6 B. G. Gowenlock, J . C. Polanyi, and E. Warhurst, Proc. Roy. SOC., 1953, A , 219,270-8 7 G. Glockler, J . Chem. Phys., 1953, 21, 1242 (see also ibid., 1951, 19, 124, andE. C. Herr, E. B. Rifbin, and H. L. Johnston, i t i d . , p. 785.Pennington, J. F. Messerly, W. D. Good, and G. Waddington, ibid., p. 5075.Gross, J. F. Messerly, R. E. Pennington, and G. Waddington, ibid., p. 2795.84 L. H. Cosgrove and P. E. Snyder, ibid., p.1227.Discuss. Faraday Soc., 1951, 10, 26)CARSON : THERMOCHEMISTRY. 33kcal./mole, B(CC, C2H,) = 62-194, B(CH, C2H6) = 85.440, B(CC, C2H,) =81.599, and B(CH, C2H4) = 89.749, are then used to calculate the resonanceenergy of benzene, which at 74.86 kcal./mole is about twice the conventionalvalue.88 This figure refers to an ethane-ethylene-like Kekuld structure andGlockler points out that the resonance energy will be very different if anothertype of Kekulk reference structure is used. This work is linked with thatof Mulliken and Parr,sg and a “ vertical ” resonance energy of 111.5 kcal./mole is obtained, the increase being due to the change C,H, (Kekulg, 1.54,1.35) ---t C6H6 (Kekuld, 1-39), which is necessary to bring the Kekulestructure into the correct configuration for resonance to occur.The“ hydrogenation ’ ’ resonance energy of benzene and the resonance energyof butadiene are also considered.The heats of formation of cycloalkanes up to C, are known, and if theheat of formation of the diradical produced by breaking a C-C bond is alsoknown, the dissociation energy of the bond can be found. SeuboldgO hascalculated the heat of formation of the diradical by combining thermochemicaldata with the energy required to transfer the corresponding alkane from astaggered to a coiled configuration. The D(C-C) values in the series C,-Cgare 50, 58, 82, 85, 83, 83, and 84 kcal./mole, with an uncertainty of &Z.Hugginsgl has pointed out that departures from the strict additivityof radii in normal valency compounds can be related to variations in the bondenergy. By using an expression of the type Y A ~ : = YA’ + YB’ - 4 log D A B ,interatomic distances can be calculated and are usually within 0.02 ofthe best experimental values.Huggins 92 has also applied new electro-negativity data to Pauling’s hypothe~is,~~ which regards a covalent bond asbeing the sum of polar and non-polar parts, in order to calculate meanbond energies which agree well with the experimental values.Both the molecular-orbital and valence-bond methods have been usedby Franklin and Fieldg4 to calculate the I1-electron resonance energies ofvarious organic free radicals and ions. The values are then used to obtainbond dissociation energies in compounds containing the radicals.Franklinhas also calculated the heats of formation of gaseous free radicals and ions 94aIto 95 has expressed intramolecular potential as the sum of interatomicbonding energies and inter-non-bonding atomic potential energies and heconcludes that irregularities in the heats of formation and the origin of thepotential barriers hindering rotation in hydrocarbons are due mainly tointeractions between non-bonding atoms in the molecule.Reviews.-Stout 96 has reviewed the whole field of thermochemistry andthe thermodynamic properties of substances. Baughan 97 has discussedthe thermochemistry of the elements of Groups IV B and IV and Long 98 theheats of iormation of simple inorganic compounds.A. S. C.G. Glockler, J . Chem. Phys., 1953, 21, 1249.F.H. Seubold, jun., ibid., 1953, 21, 1616.89 R. S. Mulliken and R. G. Parr, ibid., 1951, 19, 1271.91 M. L. Huggins, J . Amer. Chem. SOC., 1953, 75, 4126.93 I d e m , ibid., p. 4123.94 J. L. Frank’in and F. H. Field, ibid , 1953, ‘75, 2819.94a 1. L. Franklin, J . Chem. Phys., 1953, 21, 2029.95 K. Ito, ibid., p. 2430.9 7 E. C. Baughan, Quart. Reviews, 1953, 7, 103.g3 L. Pauling, ibid., 1032, 54, 3570.96 J. W. Stout, Ann. Review Phys. Chem., 1953, 4.O8 L. H. Long, ibid., p. 134.REP.-VOL. L 34 GENERAL AND PHYSICAL CHEMISTRY.3. CHEMICAL CHANGE IN HOMOGENEOUS SYSTEMS.It is hoped that, by slight variation of emphasis from year to year, thecontributions to this section of the report over any short period will togethercomprise a balanced and comprehensive account of the major contemporarydevelopments in this very large field of enquiry.The order of presentationis substantially the same as that adopted last year, but where it has seemedjustified the classification has not been rigidly adhered to.General and Theoretical.-It has long been realised that the study of veryrapid reactions is likely to yield results of high intrinsic interest, and im-portant developments have taken place in the application of four experi-mental methods. Bryce Crawford, jun., and his co-workers have describedthe adaptation for kinetic studies of a fast scanning infra-red spectrometerpreviously constructed in his laboratories2 If it is necessary to followsimultaneous changes in the concentration of two or more molecular speciesinvolved in the reaction then repetitive scanning is necessary and it is notpossible to follow reactions of half life <1 sec. If it is required to measurethe concentration changes of a single component, scanning is unnecessary,the instrument can be preset at a selected wave-length, and it becomespossible to study reactions of half life down to 0.01 sec. The mass spectro-meter, which has hitherto been used mainly for product analysis, can alsobe adapted to permit cathode-ray oscillographic presentation of mass-analyses repeated every few milli~econds.~ Flow methods are frequentlyused for studying very rapid reactions occurring in liquid media but theirapplicability is limited to reactions whose half lives exceed sec.,below which diffusion becomes rate controlling.Useful kinetic data can,in principle, be obtained for more rapid reactions than these by investigatingthe excess of acoustic absorption over a range of frequencies for a system inwhich a chemical reaction is slightly displaced from equilibrium by the soundenergy which it absorbs. The general theory of this method has been givenby Manes,5 and a less comprehensive theory by Freedman.6 The latterauthor has applied his theory to calculate from existing data the energiesof activation and the frequency factors of the dissociation of the dimers ofacetic acid and propionic acid. A weak shock wave can be used to increasethe translational and rotational temperature of a gas by a definite amountin a time of the order of few collision times.By selecting a suitable methodfor following the subsequent chemical reaction the kinetics of a rapidreaction may be determined. This method has been successfully applied byCarrington and Davidson to the dissociation of dinitrogen tetroxide in alarge excess of nitrogen or carbon dioxide at pressures between 0.5 and7 atm. and in the range -20" to 28" c.There have been several interesting developments in the theory of1 G. R. Cowan, E. Vincent, and Bryce Crawford, jun., J . Opt. Soc. Amer., 1953,43, 710.2 P. J. Wheatley, E. Vincent, D. Rotenberg, and G. R. Cowan, ibiiZ., 1951, 41, 665.3 F. P. Lossing, K. U. Ingold, and A. W. Tickner, Discuss. Faraday Soc., 1953, 14,34; K. U. Ingold and F. P. Lossing, Canad.J . Chem., 1953, 31, 30.4 E. G. Lkger and C. Ouellet, J. Chem. Phys., 1953, 21, 1310.5 M. Manes, ibid., p. 1791.7 J. Lamb and J. M. M. Pinkerton, Proc. Roy. Soc., 1949, A , 199, 114; J. Lamb and* T. Carrington and N. Davidson, J . Phys. Chent., 1953, 57, 418.E. Freedman, ibid., p. 1784.J. Huddart, Trans. Faraday SOC., 1950, 46, 540COLLINSON, DAINTON, AND IVIN : HOMOGENEOUS SYSTEMS. 35chemical kinetics. Slater has extended his earlier theory lo to cover thevariation with pressure of the first-order rate constant of a gaseous uni-molecular process. Assuming a classically vibrating molecule which disso-ciates when a particular internal dimension reaches a critical value, Slaterdeduces an expression for the ratio of the rate constant to its limiting valueat infinite pressure ; and values of this ratio at a given pressure are calculatedfor molecules with effective numbers of normal vibrations (n) varying from1 to 13.The pressure at which the rate declines from its first-order valueis shown to decrease as n is increased. Slater’s calculation leads to a pressuredependence of the rate similar to that predicted by Kassel’s theory 11 pro-vided the number of loosely coupled oscillators in the latter is set equal to(n + 1)/2. In a later paper l2 Slater applies his theory to the isomerisationof cydopropane, assuming this reaction to occur when one of the hydrogenatoms approaches within a certain distance of a neighbouring methylenegroup. His calculation leads to a frequency factor for the high-pressurerate of 4 x 1014 sec.-l and a decline of the rate constant with pressure whichis in good agreement with 0bser~ation.l~ It would be particularly valuableto extend Slater’s theory to the decomposition of dinitrogen pentoxide andnitrous oxide, for which conflicting claims as to the applicability of Kassel’sexpression have been made.l49 l5 Benson and Axworthy l6 have consideredthe kinetic consequences of distinguishing between two species, one relatedto the reactants and one to the products, both possessing the critical energyincrement, freely convertible into one another, and subject to deactivation.I t appears that in unimolecular Jissioiz processes only the activated complexcorresponding to the reactant is ever of importance whereas in bimolecularassociation reactions the complex corresponding to the products dominatesthe reaction.Almost all theories of unimolecular dissociation processeslead to the conclusion that the frequency factor will be of the same orderas the vibration frequency of a strong bond seccl). Recent worksuggests that when dissociation occurs into two large polyatomic fragmentsthe frequency factor may be several powers of ten larger than this value.An obvious explanation in terms of the transition-state theory is that whenthe reaction is the detachment of a single atom only, the formation of theactivated complex is not associated with any appreciable gain of entropy,whereas when two large fragments are formed any freedom of rotationwhich they may separately possess in the activated complex will cause anappreciable increase of entr0py.l’ This problem has been further consideredby Luft.lsAttempts to deduce a friori explicit expressions for the rate constantsof particular chemical reactions now seem to be largely abandoned in favourof seeking general relations connecting the frequency factor and energy ofactivation with one another or with other parameters.Thus Smith and9 N. B. Slater, Phil. Trans., 1953, A , 246, 57.10 Idem, PYOC. Roz. Soc., 1948, A , 194, 112.11 L. S. Kassel,New York, 1932, p. 93.l3 See ref. 44.1 5 L. S. Kassel, ibid., 1953, 21, 1093.1 6 S. W. Benson and A. E. Axworthy, ibid., p. 428.17 See also M. Szwarc, Discuss. Faraday SOC., 1953, 14, 125.18 N.W. Luft, J . Chem. Plzys., 1953, 21, 754.Kinetics of Homogeneous Gas Reactions,” Chem. Catalog. Co.,l2 N. B. Slater, Proc. Roy. SOL, 1953, A , 218, 224.14 H. L. Johnston, J . Chein. Phys., 1952, 20, 110336 GENERAL AND PHYSICAL CHEMISTRY.Eyring l9 have pointed out that in reactions involving the detachment ofa hydrogen atom from a CH group by a given reagent, e.g. , RH + C1 __tR= + HCI, the factor determining the trend of activation energies withstructure of R is the same factor which determines the bond dissociationenergy R-H and the ionisation potential of the radical R. All these pro-cesses involve the removal of charge from the carbon atom and there mustbe a flow of charge to fill this charge " hole." This flow occurs by induction,the ease of which increases in the series R = Me, Et, Prn, Pri, But, andhence the energy of activation of the hydrogen atom abstraction from RHshould (and does) decrease in that order.An alternative approach to theproblem of calculation of energies of activation of bond dissociation reactionsis to calculate the resonance energies of the resultant radical or ionic species.For this purpose x-bond resonance energies have been evaluated 2O by both" valence-bond " and the '' molecular-orbital " method for a variety oforganic radicals and ions. The dissociation of a hydrogen molecule wasconsidered in 1941 by 0. K. Rice 21 who assumed that only thermal collisionsof extremely high vibrationally excited molecules are responsible for disso-ciation. Careri22 has attempted to allow for the influence of excitedrotational states which Rice admits having overlooked.However, thereremain several unsatisfactory features in Careri's treatment.In triatomic metatheses of the type A + BC-AB + C it is usuallyassumed that there is a progressive increase in potential energy of the systemas A approaches B owing to the repulsion between atoms A and B. Bauerand WuZ3 have adopted the different view that A-B interactions can beneglected during this approach and that reaction consists of the suddenconversion of kinetic into vibrational energy when ABC has the transition-state configuration. By using values of AEI previously calculated on theEyring theory for the reaction H, + Br __t HBr + H the P factor isevaluated.The value obtained is in accord with the well-knowndifficulty of transferring energy between translational and vibrationalmodes. This method has been criticised by S. Golden 24 (and the criticismshave in turn been rebutted 25) who has presented an alternative calculationnot involving the concept of an activated complex.In transition state theory the predicted effect of pressure (fi) on the rateconstant ( k ) of a reaction is given by the equation (a In k / a f ) T = - A V ,where AVJ is the increase in volume which occurs when the activated complexis formed from the reactants, and the extensive and precise measurementsof the Imperial Chemical Industries Limited group 26 seem at first sight toprovide qualitative confirmation. Thus, they observed (1) that bimolecularassociation reactions such as the Menschutkin reaction, which are presumablyaccompanied by contraction , are greatly accelerated by increased pressure,(2) that so-called '' normal " bimolecular reactions (usually metatheses),for which A V is probably small, are only slightly influenced by pressure,19 R.P. Smith and H. Eyring, J . Amer. Chem. SOL, 1953, 75, 5183.2o J. L. Franklin and F. H. Field, ibid., p. 2819.21 0. K. Rice, J . Chetn. Phys., 1941, 9, 258.22 G. Careri, ibid., 1953, 21, 749; 0. K. Rice, ibid., p. 750.23 E. Bauer and Ta-You Wu, ibid., p. 726.24 S. Golden, ibid., p. 2071.26 See M. W. Perrin, Trans. Faraday SOG., 1938, 34, 144, and earlier papers cited in25 E. Bauer and Ta-You Wu, ibid., p. 2072.that referenceCOLLINSON, DAIKTON, AND IVIN : HOMOGENEOUS SYSTEMS.37and (3) that a reverse Menschutkin reaction, regarded as a unimoleculardissociation process and having AVt positive, decreases in rate as fl is in-creased. However, Buchanan and Hamann2' have pointed out that allthe reactions investigated involve ionic species as reactants or products orboth and that for reactions in ionising solvents the volume changes areprincipally determined by the relative degrees of solvation of the activatedcomplex and the reactants, higher solvation being accompanied by con-traction. These authors therefore measured the effect of pressure on theS N 1 type of solvolysis of tert.-butyl chloride and benzotrichloride in 80%ethanol. On Perrin's interpretation the unimolecular heterolysis which isthe rate-determining step should have AVI positive, and the reaction shouldbe retarded, If the authors' contention is correct the polarity of the transi-tion state is much greater than that of the undissociated halide and there-fore the solvation will increase, AV$ will be negative, and the reaction shouldbe accelerated.Many reactions of practical importance, eg., those leading to the produc-tion of macromolecules or involving biological substrates, are highly co-ordinated systems of simpler reactions.The mathematical treatment ofcertain of these combinations has been developed by several authors.28Bimolecular Gas Reactions.-The velocity constants of a number ofsimple bimolecular reactions have been determined, either by direct measure-ment or by measurement of the rate of the back reaction and the equilibriumconstant. The dimerisation of perfluoroethylene to perfluorocyclobutane 29and of borine to form diborane 30 have the low frequency factors expected onthe transition-state theory.An acceleration was in fact observed for both halides.It has been shown31 that the oxidationnitrosyl chloride by ozone is not a simple oxygen-atom transfer, butcatalysed by dinitrogen pentoxide, the mechanism being :123NO2 O,-NO3 + 0 24NXO, @ NO, + NO3NO, + NOCl+ NO, + NOZCIAt 40" c the rate constant k, = 0.7 x lo6 1.mole-l sec.-l. The mechanismofisofthe pyrolysis of nitric oxide- is still not settled, owing to disagreements overexperimental findings.32.30Termolecular Gas Reactions.-All the known third-order gas reactionsfall into two classes : (a) those involving two " odd-electron " molecules,e.g., nitric oxide, and (b) atom or ion recombination processes requiring athird body. Measurements have been reported on examples from eachcategory. Fairlie, Carberry, and Treacy33 have shown that the formation27 J. Buchanan and S. D. Hamann, Trans. Favaday SOC., 1953, 49, 1425.28 (Sir) Cyril Hinshelwood, J., 1953, 1947; C. A. Stewart, Biochenz. J , , 1953, 54,117; H. G. Higgins and E. J. Williams, Austral. J . Chem., 1953, 6, 195; (Mme.) M.Lautout, G. Wyllie, and M. Magat, J . Chim. Phys., 1953, 50, 199.29 B. Atkinson and A. B. Trenwith, J . , 1953, 2082.30 S. H. Bauer, A. Shepp, and R.E. McCoy, J . Amer. Chem. SOC., 1953, 75, 1003.31 H. S. Johnston and F. Leighton, ibid., p. 3612.32 F. Kaufman and J. R. Kelso, J . Chew. Phys., 1953, 21, 751; H. Wise and M. F.33 A.M. Fairlie, J. J. Carberry, and J. C . Treacy, J . Amer. Chem. SOC., 1953, '95, 3786.Frech, ibid., p. 75238 GENERAL AND PHYSICAL CHEMISTRY.of alkyl nitrites by the reaction of nitrogen dioxide on alcohols is of secondorder with respect to the dioxide and of first order with respect to the alcohol.I t is interesting to note that the rather meagre data on the methyl alcoholreaction indicate that the rate increases with decreasing temperature, andit is possible that the reaction is not termolecular but proceeds throughdinitrogen tetroxide as an intermediate according to the equations :2N0, __I, N,O, and N,O, + ROH __+c RO-NO + HO-NO,The technique of flash photolysis has been applied to the determination ofthe rate constants of the three-body recombination of iodine atoms. Thedata of all three groups of investigators agree reasonably well.Davidsonand Marshall have extended their measurements 34 to solutions in n-heptaneand carbon tetra~hloride,~~ and have shown that the rates of recombinationare respectively 130 and 40 times faster in these solvents than in argon at1 atm. pressure. Norrish and his co-workers35 have shown that thethird-order rate constant increases with atomic weight when the inert gasesare used as third bodies. Russell and Simons 36 have studied the effect ofstructure on third-body efficiency, and point out that with a large number ofcompounds investigated the only valid correlation of this efficiency appearedto be with the strength of the general van der Waals field of the third bodyas judged by the value of its boiling point.They also showed that with sixdifferent compounds used as third bodies the reaction rate fell by the sameamount (-60%) when the reaction temperature was raised from 20 to 127" c.First-order and Unimolecular Gas Reactions.-A very large number ofinvestigations of first-order gas reactions have been reported. The objectsof the researches are generally one or more of the following : (a) mechanistic,i.e., the identification of the precise chemical nature of the unimolecularstep, (b) where this is known, to evaluate the Arrhenius parameters, and(c) to discover the effect of pressure on the first-order rate constant for com-parison with theoretical predictions. Attainment of objective ( a ) is mademore difficult because many first-order decompositions occur by two con-current mechanisms, a chain reaction, the first step of which is often aunimolecular fission of a bond, and a single-stage unimolecular dissociationinto the products.Both of these unimolecular processes have intrinsictheoretical interest, and a method of distinguishing between them whichhas been frequently used is to suppress the chain reaction by the additionof an inhibitor such as nitric oxide or an olefin. This method must beapplied with care since inhibition by nitric oxide may not indicate a radicalmechanism.37 The retarding power of unsaturated compounds in dehydro-halogenation reactions appears to depend on the weakness of the C-H bondsin the retarder.38 Since an olefin is one of the products of these reactionsthe overall reaction may show aut~retardation.~~ The single-stage dehydro-halogenation reactions all have frequency factors in the range 1 0 1 2 v 5 to1014.5 sec:l which show no correlation with the activation energies. iso-34 R.Marshall and N. Davidson, J. Chem. Phys., 1953, 21, 659, 2086.35 M. I. Christie, R. G. W. Norrish, and G. Porter, Proc. Roy. Soc., 1953, A , 216, 152.36 K. E. Russell and J . Simons, ibid., 1953, A , 217, 271.37 F. H. Pollard, H. G. B. Marshall, and A. E. Pedler, Nature, 1952, 171, 1154.35 K.E. Howlett, J., 1953, 945.39 R. J . Williams, J., 1953, 113; J . H. S. Green, G. D. Harden, A. Maccoll, andP. T. Thomas, J. Chem. Phys., 1953, 21, 178COLLINSON, DAINTON, AND IVIN HOMOGENEOUS SYSTEMS. 39Propyl vinyl ether decomposes into propylene and acetaldehyde at a rategiven by kuni. = 3.8 x 1012exp( -43,56O/RT) sec.-l and with only minor free-radical side-reacti~ns.~~ Unimolecular bond-fission processes have beeninvestigated by the flow pyrolysis method,41 largely for the purpose ofdetermining bond dissociation energies (see Section 2 of this Report). Someof the frequency factors so found seem suspiciously large.42 The explanationof large frequency factors given on p. 35 may apply here and receivedsupport from a most thorough investigation of the decomposition in toluenesolution of a series of, structurally related azodinitriles of general formula([CH,],>C(CN)*N:), where x = 3, 4, 5, 6, 7, and 9.43 Very high frequencyfactors (-lo1' sec.-l) are found although E varies from 25.9 to 35.4 kcal.mole-1 owing to variations in the strain energy of the cycloparaffin rings.Trotman-Dickenson44 and others have made a careful study of theisomerisation of cyclopropane to propylene at 490" c and find their resultsagree with those of Chambers and Kistiakowsky 46 in the overlapping pressurerange and that the rate constant declines with pressure in a manner pre-dicted by Slater 12 over the range 84 to 0.07 mm.Hg. The efficiency relativeto the reactant of various added gases in collisional activation has also beendetermined for both this reaction 44 and the dissociation of cycZob~tane.4~Further studies have been made of the decomposition of n-butane4' andethane,48 both of which are somewhat complex.Isotopic-exchange reactions between dinitrogen pentoxide and l 8 0 , 4 9or 15N02 50 have been investigated and not only afford evidence of theexistence of nitrogen trioxide, which on Ogg's mechanism is considered to bean intermediate in decomposition of dinitrogen pentoxide, but also indicatethat the value of the rate constant for the unimolecular dissociationN,O, _+ NO, + NO, is 6.0 x 1012exp(-19,000/RT) sec.-l.In the pre-sence of nitric oxide every nitrogen trioxide molecule produced in theabove reaction reacts with nitric oxide according to NO, + NO --+ 2NO,,and the rate of the primary dissociation can therefore be determined. H.S.Johnston 51 has applied this principle to the determination of the activatingefficiencies of various non-reacting gases relative to dinitrogen pentoxide.The mechanism of the dinitrogen pentoxide-nitric oxide reaction has re-cently been confirmed by using the technique of fast-scanning infra-redspectroscopy to follow (a) the reaction itself and (b) the nitrogen exchangereaction between nitrogen dioxide and dinitrogen pentoxide. 52 The pyrolysis40 A. T. Blades, Canad. J . Chem., 1953, 31, 418.41 M. Ladacki and M. Szwarc, Proc. Roy. SOC., 1953, A , 219, 341, 353 ; B. G. Gowen-42 M. Szwarc and J. W. Taylor, J . Chem. Phys., 1953, 21, 1746.43 C.G. Overberger, H. Biletch, A. B. Finestone, J. Lilker, and J. Herbert, J . Amer.44 H. 0. Pritchard, R. G. Sowden, and A. F. Trotman-Dickenson, Proc. Roy. SOC.,415 T . S. Chambers and G. B. Kistiakowsky, J . Amer. Chem. SOC., 1934, 56, 399.4 7 V. A. Crawford and E. W. R. Steacie, Canad. J . Chem., 1953, 31, 937.48 B. C. Spall, F. J. Stubbs, and (Sir) Cyril Hinshelwood, Proc. Roy. SOC., 1953, A ,218, 439; C. J. Danby, B. C. Spall, F. J. Stubbs, and (Sir) Cyril Hinshelwood, ibid.,p. 450; A. D. Stepukhovich and A. G. Finkel, Zhur. Fiz. Khim., 1952, 26, 1413, 1419.C9 R. A. Ogg, J . Chem. Phys., 1953, 21, 3079.6o A. R. Amell and F. Daniels, J . Amer. Chem. Soc., 1952, 74, 6209.61 H. S. Johnston, ibid., 1953, 75, 1567.62 G. R.Cowan, D. Rotenberg, A. Downie, Bryce Crawford, jun., and R. A. Ogg,lock, J. C. Polanyi, and E. Warhurst, ibid., 1053, A , 218, 269.Chem. SOC., 1953, 75, 2078.1953, A , 217, 563. 45 Idem, ibid., 1953, A , 218, 416.J . Chew. Phys., 1953, 21, 139740 GENERAL AND PHYSICAL CHEMISTRY.of nitric acid vapour has been shown to involve the primary dissociationHNO, + HO + NO, for which the velocity constant at 400" c is 0-12sec.-l.= A decision has been made in favour of the unimolecular mechanismfor the decomposition of nitrous oxide according to the scheme :by L. Friedman and J. Bigeleisen 55 who have shown that 15N14N0 does notexchange with nitrous or nitric oxide as would be required by Pease'schain rnechani~m.~~N,O+N, + 0 ; 0 + N20+N2 + 0, or 2NO; 0 + 0(+ M)+O,N,O-N+NO; N+N,O+Ng+NONO + NO,---wN, + 0, + N ; N + NO+ N20Atomic and Free-radical Processes.-Processes involving Alkyl Radicalsand Hydrogen Atoms.-Such reactions may be conveniently classified interms of four equilibria :1Hydrocarbon + H Radical + H, ; Olefin + H ==d= Radical2Paraffin Radical + Radical ;Hydrocarbon + Radical Radical + HydrocarbonRelations of the type El - E, = AH may be used to check the experimentalenergies of activation, El and E,, or to predict one when the other is known.This is made possible by the calculation of AH froin known dissociationenergies. Complementary relations of the type R In A,/A, = AS" may beused to check the experimental frequency factors A, and A , or to predictone when the other is knowfi.This requires a knowledge of the standardentropy change AS" of the forward reaction (the standard state must bespecified when A,/A, is not dimensionless), which, in turn, requires a know-ledge of the entropy of the appropriate radicals. By assuming that theentropy of a radical R is equal to that of the hydrocarbon RH, with a cor-rection for electron degeneracy, Trotman-Dickenson 563 57 has estimatedentropy changes for the four types of process listed above, and for others.In this way a useful correlation of many experimental frequency factors canbe made.Two reviews of the kinetics of the gas-phase reactions of methyl radicalshave been The rate of combination of two methyl radicalshas been studied at high temperature by the methods of mass spectro-rnetry,61* 62 and at 165" by the rotating-sector meth0d.6~ The collisionefficiency is of the order of unity at 165" but appears to fall off at hightemperature.A pressure dependence of the bimolecular velocity constanthas been observed at 165" and low pressure, both for the combination oftwo methyl and of two trideuteromethyl radi~als.6~ The form of thedependence accords with the idea that the initially formed ethane moleculemust be stabilised by a favourable collision.5953 H. S. Johnston, L. Foering, and R. J. Thompson, J. Phys. Chem., 1953, 5'4, 390.54 R. N. Pease, ibid., 1939, 7, 749.55 L. Friedman and J . Bigeleisen, J . Amer. Chem. Soc., 1953, '75, 2215.5 6 A. F. Trotman-Dickenson, J. Chem. Phys., 1953, 21, 211.5 7 I d e m , Discuss.Faraday SOC., 1953, 14, 124.58 I d e m , Quart. Reviews, 1953, 7,198. 5s J . W. Smith, Sci. Progress, 1953, 41, 648.61 K. U. Ingold and F. P. Lasing, J. Chem. Phys., 1953, 21, 368, 1135.62 K. U. Ingold. F. P. Lossing, and A. W. Tickner, Discuss. Faraday Soc., 1953,14, 34.63 G. B. Kistiakowsky and E. K. Roberts, J. Chem. Phys., 1953, 21, 1637COLLINSON, DAINTON, AND IVIN : HOMOGENEOUS SYSTEMS. 41Relative rates of combination to disproportionation have been given forpairs of the following radicals : ethyl, approx. 8 : 1 'at 370" 64; isopropyl,2 : 1 at room temperature,65 and approx. 2 : 1 at 200-300".66The reactions of the radicals methyl and trideuteromethyl with hydrogen,deuterium, and hydrogen deuteride have been studied at 1 3 0 4 2 0 " ~ bySteacie and his co-workers 673 68 and it has been concluded 69 that all pub-lished data can be reconciled with the values 10.0 & 0.5 and 11.7 * 0-5kcal./mole, respectively, for the energies of activation of the two processes,CH, + H, CH, + H and CH, + D, CH,D + D.At a giventemperature the interaction of methyl and hydrogen deuteride to givemethane is rather faster than that to give deuteromethane. For all theseprocesses the P-factors are of the order lo-,. The thermodynamic relationslead to E = 7.0 & 1.5 kcal./mole and P -lo-, for the process CH, + HH,. These values are not compatible with the data from earlier work orwith the preliminary results of more recent work.7o It has been shownthat the exchange of deuterium atoms with methane at 350" proceeds viathe hydrogen-abstraction process CH4 + D _t CH, + HD, followed byexchange processes of the type CH, + D + CH,D + H.Tetradeutero-methane is a major product.71For the process H + C2H6 - H, + C,H5, the values E = 6.8 kcal.,P = 4.8 x have been obtained by Berlie and Le Roy,72 who used adischarge tube to generate the hydrogen atoms, and measured the rate ofconsumption of both hydrogen atoms and ethane. These values are inreasonable accord with those for the reverse process. However, Danventand Roberts,73 using the photolysis of dideuterium sulphide as source ofdeuterium atoms, find E = 9.0 kcal./mole, P = 0.6 for the analogousprocess D + C2H6 __t HD + C2H5. This energy of activation is based onthe experimental value of E = 5 kcal./mole for the process D + D,S _.+D, + DS.Other hydrocarbons give values of E which are parallel to thosefor the abstraction of hydrogen atoms by methyl radicals. Data have alsobeen obtained for the addition of hydrogen and deuterium atoms to olefins,which are in essential agreement with those of Melville and Robb. Thelatter have extended their molybdenum oxide method and have obtainedcollision efficiencies of the order 10-5-10-4 for the addition of hydrogenatoms to certain aromatic hydrocarbon^.^^Steacie and his co-workers have studied reactions of the type CH, +RH --+ CH, + R, using the photolysis of dimethylmercury 75 and ofazomethane 76 as sources of methyl radicals. The values of E and P so64 B. G. Gowenlock, J.C. Polanyi, and E. Warhurst, Proc. Roy. SOC., 1953, A,218, 269.6 5 R. W. Durham and E. W. R. Steacie. Canad. J . Chern., 1953, 31, 377.6 6 H. T. J . Chilton and €3. G. Gowenlock, Trans. Faruday SOL, 1953, 49, 1451.6 7 T. G. Majury and E. W. R. Steacie, Discuss. Faraday SOC., 1953, 14, 45.6 8 E. Whittle and E. W. R. Steacie, J . Chern. Phys., 1953, 21, 993.69 M. H. J . Wijnen and E. W. R. Steacie, Discuss. Faraduy SOC., 1953, 14, 118.70 D. J . Le Roy, ibid., p. 120.71 D. W. Coillet and G. M. Harris, J . Amer. Chem. SOC., 1953, '95, 1486.72 M. R. Berlie and D. J . Le Roy, Discuss. Faraday SOL, 1953, 14, 50.73 B. de B. Darwent and R. Roberts, ibid., p. 55.74 H. W. Melville and J . C. Robb, ibid., p. 122; P. E. M. Allen, H. W. Melville, and75 R.E. Rebbert and E. W. R. Steacie, J . Chern. Phys., 1953, 21, 1723.76 M. H. Jones and E. W. R. Steacie, Canad. J . Chenz., 1953, 31, 505.J. C. Robb, Proc. Roy. SOL, 1953, A , 218, 31142 GENERAL AND PXYSICAL CHEMISTRY.obtained are in good agreement with those from earlier work in which thephotolysis of acetone'was used as the source of methyl radicals. Energiesof activation and frequency factors have also been obtained for the attackof the alkyl radical on the parent molecule in the photolyses of dimethyl-mercury,77 a~omethane,~~ azoisopropane,65 hexadeuteroacetone,6* anddia~etyl.'~ It has been shown that at 100" methyl radicals abstract thea-hydrogen atom in isobutyryl chloride 12.4 times as fast as a p-hydrogenatom and 1.2 $: 0.2 times as fast as an a-deuterium atom.80 The processCH, + HC1- CH, + C1 has been found to occur very readily,81 withE = 2.1 5 1 kcal./mole and P -7 x Traces of hydrogen chloride areformed on photolysis of mixtures of the vapours of acetone and carbon tetra-chloride; the bearing of this on the reactions of methyl radicals with thepartially chlorinated methanes has been discussed 82 and it is concliidedthat the previously reported trend of decreasing energy of activation withprogressive substitution by chlorine atoms is still qualitatively correct.Experiments on the photolysis of methyl iodide have provided moreevidence that methane is formed only by interaction of " hot " methylradicals with methyl ** In the presence of sufficient inert gas nomethane is formed.83The possibility of the reaction CH, + CO - CH,*CO has been investig-ated at 150" by using di-tert.-butyl peroxide as radical source, andradioactive carbon monoxide.85 No reaction was detected, from which itwas concluded that k < 3 x lo6 1.mole-l sec.-l. The reverse reaction isreported to have E = 13.5 -+ 2 kcal./mole, while for Me&O --+ Me +Me2C0, E = 11.2It is well known that nitric oxide inhibits or retards reactions involvingalkyl radicals, and the occurrence of the interaction of the radicals and nitricoxide has generally been postulated. However, the nature of the primaryproducts has remained somewhat obscure. In the case of the isopropylradical it has now been shown by a flow method that the primary productsare 2-nitrosopropane Me,CH*NO, and acetone oxime Me,C:N=OH.87 In thecase of the 2-cyanoisopropyl radical also there is evidence of the formation ofan intermediate nitroso-compound.88Other RadicaZ Processes.-Information has been obtained on the rate ofaddition of trichloromethyl radicals to a variety of aromatic compoundsrelative t o that to hexadecene or styrene.89 In this way a scale of reactivitieshas been obtained which is in good agreement with theory. Melville and hisco-workers 90 have described a method by which absolute rate constants forsuch reactions of trichloromethyl radicals may be determined. Data have7 7 R. E. Rebbert and E. W. R. Steacie, Canad. J . Chern., 1953, 31, 631.7 8 M. H. Jones and E. W. R. Steacie, J . Chern. Phys., 1953, 21, 1018.79 F.E. Blacet and W. E. Bell, Discuss. Faraduy Soc., 1953, 14, 70.80 C. C. Price and H. Morita, J . Amer. Chern. Soc., 1953, 75, 3686.81 R. J. Cvetanovic and E. W. R. Steacie, Cunud. J . Chena., 1953, 31, 158.82 R. J. Cvetanovic, F. A. Raal, and E. W. R. Steacie, ibid., p. 171.83 F. P. Hudson, R. R. Williams, and W. H. Hamill, J . Chem. Phys., 1953, 21, 1894.84 R. H. Schuler and C. T. Chmiel, J . Amer. Chem. SOC., 1953, 75, 3792.85 G. B. Porter and S. W. Benson, ibid., p. 2773.8 6 D. H. Volman and W. M. Graven, ibid., p. 3111.8 7 H. T. J. Chilton and B. G. Gowenlock, I., 1953, 3232.8 8 B. Gingras and W. A. Waters, Chem. and Ind., 1953, 615.89 E. C . Kooyman and E. Farenhorst, Trans. Faraday Soc., 1953, 49, 58.90 H. W. Melville, J.C . Robb, and R. C. Tutton, Discuss. Faraduy SOG., 1953, 14, 150.2 kcal./mole.8COLLINSON, DAINTON, AND IVIN : HOMOGENEOUS SYSTEMS. 43been obtained for the addition of these radicals to cyclohexene and vinylacetate. This work provides further evidence that pairs of dissimilarradicals interact more easily than pairs of similar radicals. The ability oftrichloromethyl radicals to abstract hydrogen atoms from polyalkylbenzenesand other hydrocarbons has also been quantitatively studied.g1A neat general method, based on that of Semenov, has been given for thederivation of the rate expression of a non-branching chain reaction withalternating centres ; 92 the method is applied to the reaction between hydrogenand chlorine in the presence of nitrosyl chloride.Experimental results onthis system in the region of 300°, are in accordance with a non-branchingmechanism in which the main initiation step is NO + C1, --+ NOCl + Cl.g3The velocity constant of the process C1 + H, - HCl + H is derived andshown to fit other data, giving E = 5.5 & 0.2 kcal./mole and A - 1011 1.mole-1 sec.-l. The decomposition of nitrosyl chloride proceeds by a chainmechanism at 300' in contrast to the bimolecular mechanism at lower tem-peratures.94 Published data have been used to calculate A = 4 x 109 1.mole-1 sec.-l, E = 20.3 kcal./mole for the process NO + C1, _t NOCl +Cl.95 I t has been shown that nitrogen trichloride undergoes explosivedecomposition below a certain pressure and will induce explosive combinationof hydrogen and chlorine at low pressure in the dark.96The exchange of iodine atoms between organic iodides and elementaryiodine usually proceeds via iodine atomsg7 Two mechanisms have beendistinguished : type 1, RI + I* __t RI* + I, is shown by allylic and aryliodides; type 2, RI + I __t R + I,, R + I, -+ RI + I, is shown byalkyl iodides.Ally1 iodide is exceptional in exchanging mainly by a non-atomic mechanism.98 The photochemically induced exchange of ally1iodide proceeds rapidly by an atomic mechanism.99Photochemistry.-Actinometry.-The photolysis of potassium ferrioxalatein aqueous solution results in the formation of ferrous iron which may beestimated colorimetrically in very small amounts by means of the complexformed with o-phenanthroline. This photolysis provides a chemicalactinometer which is 100 times more sensitive than the uranyl oxalateactinometer, and approximate quantum yields have been determined a ttwelve wave-lengths between 4900-2537 A.Absorption Spectra of Intermediates.-The absorption spectra of a numberof intermediates of photochemical reactions have been observed by themethod of flash photolysis. In this way the spectra of ClO,105 CHO,101NH and NH, lo2 have been observed.By using a multiple-reflectionsystem providing an effective path length of 20 m., Ramsay lo3 has alsobeen able to observe the NH, bands in continuously photolysed ammonia.The intensity of the bands was comparable with that of the bands obtainedby flash photolysis. It is interesting to note that a similar multiple-reflectionDl E.C. Kooyman and A. Strang, Rec. Trav. chim., 1953, 72, 329, 342.92 P. G. Ashmore, Trans. Faraday SOC., 1953, 49, 251.D3 P. G. Ashmore and J. Chanmugam, ibid., p. 254.94 Idem. ibid., p. 265.96 P. G. Ashmore, Nature, 1953, 172, 449.D7 R. M. Noyes and D. J. Sibbett, J . Amer. Chem. Soc., 1953, 75, 767.Ds Idem, ibid., p. 761.D5 Idem, ibid., p. 270.O9 Idem, ibid., p. 763.loo C. A. Parker, Pvoc. Roy. Soc., 1953, A , 219, 104.lol D. A. Ramsay, J . Chem. Phys., 1953, 21, 960.102 Idem, J . Phys. Chem., 1953,57,415. lo3 Idem, J . Chem. Phys., 1953,21,16544 GENERAL AND PHYSICAL CHEMISTRY.method has enabled the absorption spectra of the radicals OH, SH, CS, CN,and NH, to be observed on passing an electric discharge through appropriatecompounds.lo4The absorption bands of C10 have been observed after flash irradiationof a mixture of chlorine and oxygen.lo5 The radicals disappear by a bi-molecular process which has no energy of activation and a collision efficiencyof the order Since the direct process 2C10 ---;tCl, + 0, would beexpected to have a considerable energy of activation it is postulated thatC1,0, is formed as an intermediate. The chlorine-photosensitised exchangebetween the isotopes of oxygen probably involves the intermediate formationof C10 radicals.lo6Photolysis of Aldehydes and Ketones.-The photolysis of glyoxal vapourby light of wave-length 3130 A results in the formation of carbon monoxide($GO = 1-2), hydrogen (+H~ = 0-13), and f0rma1dehyde.l~~ The quantumyields are relatively insensitive to changes of temperature and pressure or toaddition of inert gas, so that the photolysis may be represented completelyin terms of the two primary processes :(15%) 2CO 3.H, f-- (CHO),* __t CH,O + CO (85%)An explanation of certain discrepancies arising in the high-temperaturephotolysis of acetaldehyde has been suggested. lo8 The photolyses ofacetaldehyde, acetone, and diacetyl have been studied at very high in-tensity. 109 Under these conditions radical-radical reactions predominate,and the reactions of radicals with the parent molecules are unimportant.Particularly striking is the fact that ethane is formed in the photolysis ofacetaldehyde, even in the presence of an excess of carbon dioxide (whichminimises the temperature rise).Ethane has hitherto been undetected inthe normal photolysis at room temperature, owing to the rapidity of theprocess, CH, + CH,*CHO __t CH, + CH,*CO. The ratio of the quantumyields for the primary processes (1) and (2) is found to be +1/+2 < 1-1.CH, and CH, remain undetected by absorption spectra.104(2) CH, + CHO f-- CH,CHO* + CH, + CO (1)that diacetyl formation in the photolysis ofacetone cannot account for the apparent change in the energy of activationof CH, + CH,*CO*CH, __t CH, + CH,CO*CH, at about 120". Thefluorescence of acetone and diacetyl 112 vapour has been studied. Inboth cases fluorescence occurs from two excited states, one of which isquenched by oxygen. The photolysis of diacetyl vapour has been investig-ated at 2654A between 28-200°, and a mechanism proposed to accountfor the experimental quantum yields.l13 An investigation of the photolysisof acetone vapour in the presence of carbon tetrachloride has shown thatthe latter does not act simply as a diluent but is involved in some processIt has been concluded104 P.J. Dyne, Canad. J . Phys., 1953, 31, 453.105 G. Porter and F. J. Wright, Discuss. Faraduy SOL, 1953, 14, 23.106 R. A. Ogg, J . Chem. Phys., 1953, 21, 2078.107 J. G. Calvert and G. S. Layne, J . Amer. Chem. Soc., 1953, 75, 856.1 0 8 H. 0. Pritchard, G. 0. Pritchard, and A. F. Trotman-Dickenson, J . Chem. Phys.,109 M. A. Khan, R. G. W. Norrish, and G. Porter, Proc. Roy. SOL, 1953, A , 210, 312.110 H.J. Groh, E. D. Becker, and W. A. Noyes, Discuss. Faraduy Soc., 1953, 14, 128.111 H. J. Groh, G. W. Luckey, and W. A. Noyes, J . Amer. Chew SOL, 1953, 21, 115.112 H. J. Groh, J . Chem. Phys., 1953, 21, 674.113 F. E. Blacet and W. E. Bell, Discuss. Faraday Soc., 1953, 14, 70, 131.1953, 21, 748COLLINSON, DAINTON, AND IVIN HOMOGENEOUS SYSTEMS. 45leading to the formation of hydrogen chloride.*l It appears that carbontetrachloride undergoes an acetone-photosensitised decomposition to giveCCl, + C1. The hydrogen chloride subsequently formed has a markedeffect on the relative amounts of the photolysis products of acetone (seep. 42).Reactions Involving Halogen Atoms.-The photochemical formation ofcarbonyl chloride has been further studied and the mechanism extended toinclude wall-termination a t low pressure.114 The photolysis of methyliodide has been shown to involve " hot " methyl radical^.^^^^^ The photolysisof trifluoromethyl iodide results in the formation of perfluoroethane andiodine. 115 The gas-phase bromination of toluene has been studied, bothphotochemically (82-132') and thermally ( 166').l16 The combined resultslead to a value of E = 7.2 kcal./mole for the process Br + Ph-CH, -+Ph*CH,* + HBr. A study of the kinetics of the inhibition by hydrogenbromide gives a value of E = 5.0 kcal./mole for the reverse process (cf.p. 28). The photochlorination of methyl chloroformate has been studiedin the gas phase and the results compared with those obtained for thereaction in carbon tetrachloride solution.117Other Direct Photochemical Reactions.--A detailed investigation has beenmade of the photochemical and thermal decomposition of hydrogen sulphidein the range 27-650"/8--550 mm. and at wave-lengths 2288 A and 2550 A,11sthe decomposition of hydrogen bromide being used as actinometer at 2288 A.The quantum yield +Ez at room temperature is found to increase slightly withpressure to a limiting value of 1-26. At high pressures it is assumed thatall the hydrogen atoms produced in the primary process (1) disappear byprocess (2) so that the mechanism simplifies to :hv(1) H,S+H + HS(2) H + H,S--+H, + HS(3) 2HS+Hz + '32(4) 2HS ---P 33,s + sand the limiting quantum yield is accounted for by supposing that k,/k, -6.7.The photolyses of the vapours of dirnethylmerc~ry,~~ azomethane,78 andazoisopropane 65 have been investigated as potential sources of alkyl radicals(see p.42). In the case of azomethane it was shown that +N$ = 1 and isindependent of temperature in the range 24-190".The photolysis of ethyl nitrate vapour has been studied at a number oftemperatures, and the products analysed. 119 The evidence indicates thatthe ethoxy-radical formed in the primary process can undergo two modesof decomposition :(1) C,H,.O __)_ CH, + CH,.O; (2) C,H,.O + H + CH,*CHOThe final products of photolysis of anthracene (A) in carbon tetrachloridecan be explained by assuming the intermediate formation of AC1 and CCI,radicals.120 The effects of temperature, solvent, and a second aromatic114 L.Fowler and J. J. Beaver, J . Amer. Chem. SOL, 1953, 75, 4186.115 J. R. Dacey, Discuss. Furuduy Soc., 1953, 14, 84.116 H. R. Anderson, H. A. Scheraga, and E. R. van Artsdalen, J. Chem. Phys., 1953,117 J. H. Brandy and D. J. Le Roy, ibid., p . 1049.11* B. de B. Darwent and R. Roberts, Proc. Roy. Soc., 1953, A, 216, 344.119 J. A. Gray and D. W. G. Style, Trans. Furaday SOC., 1953, 49, 52.E. J. Bowen and K. K . Rohatki, Discuss. Furuduy SOC., 1953, 14, 146.21, 125846 GENERAL AND PHYSICAL CHEMISTRY.hydrocarbon on the fluorescence of substituted anthracenes have beeninvestigated, and it is concluded that transfer of energy can occur overdistances of many molecular diameters.1211122Photosensitised. Reactions.-An unsuccessful attempt has been made tosynthesise ammonia from nitrogen and hydrogen by xenon-photosensitisation(1470 This lack of success is taken as evidence against the valueD(N,) = 171 -3 kcal./mole.The mercury-photosensitised reaction of cyclo-butane results in the formation of hydrogen, n-butylcyclobutane and asaturated compound, CSH14, which is apparently ~yclobutylcyclobutane.~~~Quantum yields were measured at 30". The proposed mechanism involvesthe primary process, cycZo-C4H,* __t cyclo-C,H, + H, followed by dimeris-ation of the cyclobutyl radicals to form n-butyl- and cyclobutyl-cyclobutane.The mercury-photosensitised decomposition of ethylene has been re-investig-ated, very monochromatic light of wave-length 2537 A being used.125Reactions Involving Oxygen.-The mechanism of quenching of mercury6(3P1) atoms by oxygen has been discussed in relation to ozone formation,126exchange of 0, and 1802,12' and the photosensitised oxidation of paraffins.12,The exchange reaction occurs by a chain mechanism and must involve theprocess 0 + 0, - 0, + 0.The same process must occur in the ozone-catalysed exchange between oxygen molecules.129 The mercury-sensitisedphoto-oxidation of propane to give isopropyl hydroperoxide has beenstudied.130 The photo-oxidation of solutions of various substituted anthra-cenes by dissolved oxygen has been followed by measuring the rate of uptakeof 0xygen.1~1 The quantum yield is independent of the oxygen concentrationbut is a function of the anthracene concentration.The reaction is interpretedin terms of a reactive intermediate for which anthracene and solvent moleculescontaining C-H bonds compete.A detailed mechanism has been proposed for the anthraquinone-sensitisedphoto-oxidation of alcoh01s.l~~ In the case of ethyl alcohol it has beenshown that the products are acetaldehyde, acetic acid, and hydrogen per-oxide. Acetic acid is a primary product and is not formed by secondaryoxidation of the aldehyde. The quantum yield 40, =1 1, and is independentof temperature. The sensitiser (A) acts by breaking a C-H bond of thealcohol, A + CH3*CH2*OH - AH + CH,CH*OH, but is regenerated bythe process, AH + 0, - A + HO,. The relative proportions of theproducts depend on the relative concentrations of the intermediate peroxy-radicals, which in turn depend on the concentrations of sensitiser andpressure of oxygen, but which are independent of light intensity and alcoholconcentration.The kinetics of photo-oxidation of benzaldehyde in n-decane at 5-20'121 E.J. Bowen and R. J. Cook, J . , 1953, 3059.122 E. J. Bowen and €3. Brocklehurst, Trans. Favaday Soc., 1953, 49, 1131.123 M. H. J. Wijnen and H. A. Taylor, J. Chem. Phys., 1953, 21, 233.124 D. L. Kantro and H. E. Gunning, ibid., p. 1797.125 ,4. G. Mitchell and D. J. Le Roy, ibid., p. 2075.126 D. H. Volman, ibid., p. 2086.1 2 7 W. H. Johnston and C. J. O'Shea, ibid., p. 2080.128 J. A. Gray, ibid., p. 1300.129 R. A. Ogg and W. T. Sutphen, ibid., p. 2078.130 N. V. Fok and A. B. Nalbandyan, Chem.Abs., 1953, 47, 3124.131 E. J. Bowen, Discuss. Faraday Soc., 1953, 14, 143.132 J. L. Bolland and H. R. Cooper, Nature, 1953, 1'92, 413COLLINSON, DAINTON, AND IVIN HOMOGENEOUS SYSTEMS. 47are in accord with the following chain mechanism at high concentrations ofoxygen, when (4) is the main termination process : 133hv(1) PhCHO PhCO + H(2) PhCO + 0, + PhCO.00(3) Ph.CO.00 + Ph-CHO + PhCO*OOH + PhCO(4) 2Ph.CO.00 __t terminationBy the use of the retarder and rotating-sector techniques the followingvalues have been obtained : E, = 1-8 0.5, E, - 1 kcal./mole ; A , = 5 xlo4, A , = 8 x lo9 1. mole-l sec.-l. The mechanism is analogous to that ofa simple vinyl polymerisation reaction. Further, it has been shown thatthe kinetics of the simultaneous photo-oxidation of benzaldehyde anda-decanal are analogous to those of a copolymerisation r e a ~ t i 0 n .l ~ ~ Bothaldehydes are involved in a single kinetic chain and by the application ofstandard copolymerisation methods the rate constants of the four propagationsteps, as well as the cross-termination coefficient, have been evaluated. Thephoto-oxidation of pure liquid acetaldehyde between -90" and -40" showskinetics which are identical in every respect with those for benzaldehyde andn-decanal in s01ution.l~~Some exploratory investigations have been made of the photo-oxidationsof acetone 1369 13'9 138 and diethyl ketone 139 below 200". The reactionsproceed via the initial formation and subsequent oxidation of alkyl radicals.A comparison has been made with the photo-oxidations of dimethylmercuryand methyl iodide,140 the conclusion being that both carbon monoxide anddioxide ultimately result from the oxidation of the methyl radical. In thecase of diethyl ketone, tracer experiments using Et,l*CO indicate that at30" most of the carbon dioxide formed is 14C0,, whereas at 102" a largeproportion comes from the oxidation of the ethyl radical.The kinetics of the chemiluminescent reaction between zinc tetraphenyl-porphin and tetralin hydroperoxide have been investigated as part of a studyof the mechanism of dye-sensitised photo-oxidation reactions.141Fluorescence.-A method of determining fluorescence life-times with anaccuracy of 1% at 2 x 10-8 sec. has been described.142 The fluorescence isexcited by light modulated at high frequency, and the life-time estimatedfrom the phase difference between the exciting light and the resulting fluor-escence.Measurements on the fluorescence of acetone,lll diacetyl,l12and substituted anthracenes already have been referredReactions in Solution.-Electron-transfer Processes between Ions containingthe Same MetaL-In an earlier theory of electron-exchange reactions amechanism based on the tunnelling of a potential barrier was advanced; 143133 T. A. Ingles and H. W. Melville, Proc. Roy. Soc., 1953, A , 218, 175.13* Idem, ibid., p. 163.135 P. Fillet, M. Niclause, and M. Letort, Compt. rend., 1953, 236, 1489.136 P. E. Frankenburg and W. A. Noyes, J . Amer. Chew Soc., 1953, 75, 2847.13' D.E. Hoare, Trans. Faraday SOC., 1953, 49, 1292.13* R. R. Heutz, J . Anzer. Chem. Soc., 1953, 75, 5810.139 A. Finkelstein and W. A. Noyes, Discuss. Faraday SOC., 1953, 14, 76, 81.140 R. B. Martin and W. A. Noyes, J . Anzer. Chem. SOC., 1953, 75, 4183.141 H. Linschitz and E. W. Abrahamson, Nature, 1953, 172, 909.142 E. A. Bailey and G. K. Rollefson, J . Chem. Phys., 1953, 21, 1315.143 R. J. Marcus, B. J. Zwolinski, H. Eyring, and J. D. Spikes, US. Atomic En.Commiss. Report, AECU-227148 GENERAL AND PHYSICAL CHEMISTRY.a more quantitative extension of this theory has now been made.144 Asjudged by the experimental results so far available, there are apparently twotypes of electron-exchange reactions : (i) those with low activation energyand negative entropy of activation and (ii) those with high activation energyand positive entropy of activation.The theory developed, which agreeswith that by Libby 145 inasmuch as it depends on the applicability of theFranck-Condon principle, provides an explanation for these two possibilities.The expression derived for the specific rate constant of electron exchangecontains a negative entropy of activation term in the form of an electronictransmission coefficient, and a positive entropy of activation term as partof the free energy of rearrangement, the sign of the actual entropy of activ-ation depending on which is predominant. The expression implies that theremay not in fact be two clear cut groups of reactions. On the basis of theelectron tunnelling theory it is claimed that the current " catalytic,"" bridge," and " group exchange '' theories can be reconciled.In reactions of this type it has generally been found that only systemsinvolving positive ions react at measurable rates.However Sheppard andWahl 146 have been able to investigate the rate of electron transfer betweenmanganate and permanganate ions in sodium hydroxide solution. Theexchange follows a second-order law with a half life of 12 sec. at a concen-tration of 9 x 1 0 - 5 ~ . The fact that the rate of exchange is small com-pared with the collision frequency indicates that in aqueous solution theprobability of electron transfer from the MnO,= ion to a contiguous Mn0,-ion is small.In any given case it is not yet known whether electron transfer involvesthe jump of a free electron or whether a group such as OH or H accompaniesit.Another effect not fully understood is the catalysing action of anioniccomplex-forming agents in many of the exchange reactions between simplecations. It has been pointed out that the reason for the lack of informationin these directions lies in the general lability of changes in the co-ordinationBy oxidising Cr(I1) in the presence of chloride ions, chlorine wasfound to be attached to the resulting Cr(m), indicating that Cr-Cl bondswere formed in the activated complex. By using a complex oxidising ion,slow with respect to substitution, viz., Co(NH,),C12+, the electron transferin this case was shown directly to involve chlorine-atom transfer. Hydrogen-atom transfer has been suggested as the mechanism of electron transferbetween the ions Fe2+ and FeF2+, FeF2+, or FeF3,148 since the effect of theaddition of fluorine ion is to bring about very little change in either the ratesof exchange or the entropies of activation.Earlier work on the disproportionation of PU(IV) in perchloric acidsolutions has been corrected for the influence of M particles, and the mechan-ism found to be consistent with that previously deduced from the dis-proportionation of P U ( V ) .~ ~ ~ These results have also been confirmed byother workers,150 the most probable rate-determining step being PuOH3+ +P u ( O H ) ~ ~ +144 R. J. Marcus, B. J. Zwolinski, and H. Eyring, U.S. Atomic En. Commiss. Report,AECU-2620.145 W. F. Libby, J . Phys. Chem., 1952, 56, 863.1 4 6 J. C. Sheppard and A. C. Wahl, J . Amer. Clzem. Soc., 1953, 75, 5133.147 H. Taube, H. Myers, and R. L. Rich, ibid., p. 4118.1 4 8 J. Hudis and A. C. Wahl, ibid., p. 4153.149 R. E. Connickand W. H. McVey, ibid., p. 474.Pu3+ + PuO,' + H20 + H+.I5O S. W. Rabideau, ibid., p. 474COLLINSON, DAINTON, AND IVIN HOMOGENEOUS SYSTEMS. 49Atom and Group Transfer.-Apart from reactions involving Cr(rr),exchanges of chromium between different Cr(m) species have generallybeen found to be slow. It has now been shown that there is negligibleexchange between the chromic ion and the chromate ion in aqueous solu-tion.151 The exchange of lead between the plumbite and the plumbate ion in7~-potassium hydroxide solution occurs at approximately 80".152 In agree-ment with the non-existence of exchange between Pb(r1) and Pb(1v) inacetic acid,153 it was found that a heterogeneous exchange of lead betweensolid Pb,O, and a solution of Pb(r1) involved only the bivalent lead in theoxide.Several investigations involving the exchange of sulphur have beenmade. Exchange of sulphur between sulphurous acid and dithionous acidwas complete within 20 sec. for solutions on the acid side of pH 7.15, InN-sodium hydroxide no exchange occurred in 90 sec. A study of the exchangeof 35S between the diethyl polysulphides indicated that exchange occurredonly with sulphur atoms not attached to carbon and that the sulphur atomswere not equivalent. On the other hand all the sulphur atoms in the sodiumpolysulphides appeared to be equivalent The exchange of sulphurbetween solutes and liquid sulphur dioxide l56 or liquid hydrogen sulphide 15'has been investigated.Unlike the exchange of iodine between molecular iodine and alkyl iodides,which proceeds by a free-radical mechanism, 158 the corresponding exchangewith ally1 iodide does not involve radicals.159 In this respect its behaviouris claimed to be unique among organic halides.The mechanism is bi-molecular and its high negative entropy of activation suggests the formationC H ~ ~ C H - C H ~ of an activated complex of the type shown inset. ThereI-----I-----I iodine monochloride and benzyl halides or isopropyl iodidein carbon tetrachloride.160 The mechanism is obscure, but a complex[RX-ICl] is probably formed with the isopropyl iodide.A complex of thetype [Br*-EtBrJ has been shown to be formed during the exchange of brominebetween ethyl bromide and sodium bromide in ethyl alcohol.161The exchanges of X between K,PtX, and NH,X* in aqueous solution(where X* = 38Cl, 8oBr and s2Br, lzaT or C15N) proceed at very differentrates.162 Paradoxically the exchange is faster the greater the stability ofthe complex, this being understandable if the exchange is regarded from theviewpoint of the ease of penetration of the added anions into the inner co-ordination sphere. The exchange of oxygen between water and hydrated151 A. H. W. Aten, H. Steinberg, D. Heymann, and A. Fontijn, Rec. Trav. cltim., 1953,72, 94.153 E.A. Evans, J. L. Huston, and T. H. Norris, J . Amer. Chem. Soc., 1952, 74, 4985.15* H. B. van der Heijde, Rec. Trav. chzm., 1953, 72, 95.155 E. N. Gur'yanova, Y . K. Syrkin, and L. S. Kuzina, Doklady A k a d . Nauk S.S.S.R.,I 1 may be a different mechanism for exchange of iodine between152 A. Fava, J . Chim. Phys., 1953, 50, 403.1952. 86. 107.156 R. H. Herber, T. H. Norris, and J. L. Huston, U.S. Atomic En. Commiss. Report,1 5 7 T. H. Norris and R. C. Smith, ibid.. AECU-2657.AECU-2606.15* R. G. Badger, C. T. Chmiel, and R. H. Shuler, J . Anzcr. Chem. Soc., 1953, 75,180 R. M. Keefer and L. J. Andrews, ibid., p. 543.161 M. B. Neiman, G. V. Makstmova, and Y . M. Shapovalov, Doklady Akad. NaGk2498. 15n D. J. Sibbett and R. M. Noyes, ibid., p.761.S.S.S.R., 1952, 85, 1289.A. A. Grinberg and L. E. Nikol'skaya, Zhur. Priklad. Khim., 1951, 24, 89350 GENERAL AND PHYSICAL CHEMISTRY.chromic chloride 163 has been examined in non-acid solutions. In contrastto the results for solutioiis containing mineral acid 164 there is no specificeffect of anions, and the activation energy for the exchange in non-acidsolutions is significantly higher. An anion-exchange mechanism equivalentto isomerisation is suggested. In non-acid solutions direct exchange ofthe hydroxyl ion is assumed to predominate, whilst in acid solutions exchangeis brought about mainly by other anions.The exchange of oxygen between gaseous oxygen and liquid water hasbeen found to occur in the presence of hydrogen peroxide or of catalysts fordecomposition of the latter.165 Since catalase comes into this category, carewill be needed in the interpretation of tracer experiments in photosynthesis.At low concentrations of nitric acid the exchange of oxygen betweennitric acid and water occurs only in the presence of lower oxides of nitrogen(“ nitrous acid ”), but at higher acid concentrations these are not necessary.166The kinetics suggest a two-stage mechanism involving exchanges betweenwater and nitrous acid and between nitrous acid and nitric acid.Some interesting experiments have been reported on exchanges betweengaseous hydrogen and various solutions.The exchange between hydrogengas and aqueous potassium hydroxide, studied with both deuterium andpara-hydrogen, was found to be homogeneous and of first order in hydrogenand hydroxyl-ion concentration.167 No exchange occurred in acid solutions,and arguments are advanced for considering the mechanism to beD, + OH- _+ D- + DOH, followed by H,O + D- ---+ OH- + HD. Asimilar, but experimentally less well founded, mechanism has beensuggested for the corresponding exchange between hydrogen and potass-amide in liquid ammonia.16s Exchanges involving hydrogen gas can alsobe brought about by the use of solutions of cuprous acetate in quin-0line,1~~ 170 a system which can be used for homogeneous catalytic reduction.The rate of exchange is found to be proportional to the first power of thehydrogen concentration and to the square of the cuprous acetate concen-tration, which may indicate that the mechanism involves a dimeric coppercomplex and that the rate-determining step is (CuI), + H, + (Cu1),*2H,the hydrogen being in a dissociated state.169 I t has also been suggestedthat the mechanism involves addition of hydrogen to the double bond in thequinoline ring, giving an unstable c0rnp1ex.l~~ The fact that other solventscan be used, provided they are nitrogen bases,169 seems to be against thishypothesis.Electron-transfer Reactions Involving the Formgtion of New Species.-Anew method has been proposed for utilising the oxidation of hydrazine inclassifying oxidising agents as l-electron or 2-electron transfer agents.171On this basis the previous classification of hydrogen peroxide as a “ di-delectronator,” and of halogens as “ monodelectronators,” is disputed.163 H.A. E. Mackenzie and A. M. Milner, Trans. Faraday SOC., 1963, 49, 1437.f G 5 H. A. E. Mackenzie and A. M. Milner, J , S. African Chem. I m t . , 1931, 4, 79.166 C. A. Bunton, E. A. Halevi, and D. R. Llewellyn, J . , 1952,4913,4197; 1953, 2653.16’ W. K. Wilmarth, J. C . Dayton, and J . M. Floumoy, J . Amer. Chem. Soc., 1953,lB9 S. Weller and G. A. Mills, ibid., p. 769.170 W. K. Wilmarth and M. K. Barsh, ibid., p. 2237.171 W. C. E. Higginson, D. Sutton, and P. Wright, J . , 1953, 1380.R. A. Plane and H. Taube, J . Chem. Phys., 1952, 56, 33.75, 4549. 16* W. K. Wilmarth and J. C. Dayton, ibid., p. 4553.R. E. Kirk and A. W. Browne, J . Anzer. Chem. SOC., 1928, 50, 337COLLINSON, DAINTON, AND WIN : HOMBGENEOUS SYSTEMS.51The mechanisms proposed for the l-electron and %electron transfer reactionsof hydrazine have been confirmed by using 15N as a tra~er.l7~ Anothercriterion 174 for distinguishing l-electron and %electron transfers has beenapplied to the reduction of aa-dimethylbenzyl hydroperoxide by the iodideion. A single stage 2-electron transfer process was indicated but successivel-electron transfers were not eliminated.175Participation of radical ions of the type X,- (where X = C1, Br, I, orCN) has frequently been postulated for processes involving electron transfer.The (SCN),- ion has now been added to the list, having been found to occuras an intermediate in the spontaneous bleaching of acid aqueous solutions offerric thi0~yanate.l'~ This reaction occurs via the FeSCN2+ and Fe(SCN), +ions, and also involves (SCN), as an intermediate.The I,- ion is apparentlythe only possible intermediate which can act as a catalyst for the reductionof oxygen in the pervanadyl-iodide rea~ti0n.l~' The complete mechanisminvolves a tennolecular process, I,- + 0, + H+ - I, + O,H, which,owing to the low concentration of I,-, seems rather unlikely. Consequentlyit is suggested that the ion HO,+ may have independent existence.The kinetics of the Ce(Iv)-Cl- reaction in perchlorate have been studied.178The formation of higher oxidation states of chlorine at low chlorine concen-trations was prevented by adding thallous perchlorate, Tl(r) not being oxidiseddirectly by Ce(1v) when chloride ion is present. The most probable firstproduct is the radical ion C1,- formed in the process CeCP+ + Cl- -+Ce3+ + C1,-.The mechanism of the Ce(1v)-Br- reaction in sulphuric acidappears to involve activated complexes of two different compositions, viz.,Ce(SO,),Br," and Ce(S0,),Br-.179 The radical ion Br,- probably cccursas an intermediate. The Ce(1v)-I- reaction in sulphate media at pH 3appears to involve the existence of colloidal Ce(Iv), which is responsible fora slow reaction.lT9 Heterogeneous effects have also been observed in thephoto-reduction of Ce(w),lS0 and a surface-catalysed mechanism involvingadsorbed hydroxyl radicals has been suggested for the thermal oxidation ofwater by cerium perchlorate.lslTwo authors have reconsidered the mechanism of the autoxidation offerrous ions in aqueous solution.ls29 lS3 Both agree that the exothermicinitial step, Fe2+ + 0, =$z Fe3+ + 02-, cannot be correct.For solutionshaving a high concentration of hydrochloric acid, in which the autoxidationis rapid, Posner considers the initial step to be HFe,+Cl + 0, _t HO, +Fe3+ + C1-. There is some independent support for the existence of thecomplex HFe2+C1. Weiss suggests that the primary step should be writtenFe2+ + 0, + (Fe3+0,-). The overall accelerating effect of some anionsis then interpreted as due to stabilisation of the above complex in additionto the subsequent complex formation with ferric ions. The kinetics of the1'3 W. C . E. Higginson and D. Sutton, J., 1953, 1402.174 H. Taube, J .Amer. Chem. SOC., 1942, 64, 161.175 H. Boardman and G. E. Hulse, ibid., 1953, 75, 4272.176 R. H. Betts and F. S. Dainton, ibid., p. 5721.177 M. H. Boyer and J. B. Ramsey, ibid., p. 3802.17s F. R. Duke and C. E. Borchers, ibid., p. 5286.179 E. L. King and M. L. Pandow, ibid., P. 3063.1 8 0 B. Y . Dain and A. A. Kachan, Doklady Akad. Nauk S.S.S.R., 1949, 67, 85.181 F. R. Duke and J. A. Anderegg, Iowa State Coll. J . Sci., 1953, 427, 491.182 J. Weiss, Experientia, 1953, 9, 61.183 A. M. Posner, Traits. Faraday SOC., 1953, 49, 38252 GENERAL AND PHYSICAL CHEMISTRY.autoxidation in the presence and absence of fluoride ion suggest that in thelatter case the complex is stabilised to some extent by ferrous ions, e.g.,(Fe3+*02-) + Fe2+ ( Fe3+.0,-.Fe2+) e-(Fe2+.0,*-.Fea+) --+ 2Fe3+ + H0,- + H+The kinetics of the Fe(n)-Tl(IrI) reaction in perchloric acid have againbeen examined; 184 they are consistent with the mechanism :Though it is known that the reaction can take two paths involving twotransition complexes, it is still uncertain just what ion species take part.In the initiation or catalysis by metal ions of certain types of reactioninvolving organic compounds, iron salts continue to be of major interest.Thus Bates and Uri 185 have examined the oxidation, induced by photo-excited electron transfer in iron complexes, of various aromatic compounds.The initial step in the reduction of aa-dimethylbenzyl hydroperoxide by thef errocyanide ion 186 or the reaction between aa-dimethylbenzyl hydro-peroxide and ferrous salts The reaction be-tween organic hydroperoxides and iodide is catalysed by the presence offerrous salts which act by the alternate oxidation and reduction ofiron.ls8 Ferrous salts also catalyse the reactions between aa-dimethylbenzylhydroperoxide and polyethylene polyamines 189 and between the nitrosyl-disulphonate and the hydroxylaminemonosulphonate ions.lS0 Fenton’sreaction comes into this category and aspects of it have been discussed intwo papers.19l~ 192 Baxendale and Magee have gone far towards elucidat-ing the mechanism of the oxidation of benzene.The products are phenoland diphenyl only. The phenyl radical does not react with hydrogenperoxide but may be reduced by ferrous ions to benzene and oxidised byferric ions to phenol.Thus care is needed in comparing the action ofFenton’s reagent on a substrate with that of other sources of hydroxylradicals. The above type of behaviour is considered to be general, andWaters 19% 193 has suggested that chain reactions arise when the organicradicals concerned have reduction potentials less negative (on the U.S.scale) than that for the process Fe3+ & Fe2+ + e. This is the startingpoint of a revised theory of enzyme oxidations lS2 in which no free radicalsare generated.The catalyses of the chain autoxidations of aldehydes and unsaturatedhydrocarbons by the cobaltic ion are initiated by electron transfers of thetype,lS4 C O ~ + , ~ . + RH R + CO’+~~. + Hfaq..Reactions of Hydrogen Peroxide.-The rate constant for the initial step ofthe H202--Fe2+ reaction in dilute sulphuric acid has been redetermined.lg5 Theresults can be expressed as k , = 3.9 x 109exp(-11,000/RT) 1.mole.-l sec.-l.T~(III) + Fe(I1) Tl(11) + Fe(m) ; T~(II) -J- Fe(1r) + T~(I) + Fe(II1).is a single-electron transfer.184 K. G. Ashurst and W. C. E. Higginson, J., 1953, 3044.195 H. G. C. Bates and N. Uri, J. Amer. Chem. Soc., 1953, 75, 2754,186 H. Boardman, ibid., p. 2648.1 8 7 W. S. Wise and G. H. Twigg, J., 1953, 2172.lag R. J . Orr and H. L. Williams, Discuss. Faraday Soc., 1953, 14, 170.lgo W. J . Ramsey and D. M. Yost, J. Chem. Phys., 1953, 21, 957.191 J . H. Baxendale and J . Magee, Discuss. Faraday SOC., 1953, 14, 160.lg2 D. J . Mackinnon and W. A. Waters, J., 1953, 323.193 W.A. Waters, Discuss. Faraday SOC., 1953, 14, 233.194 C. E. H. Bawn, ibid., p. 181.195 W. Taylor and J. Weiss, J. Chern. Phys., 1953, 21, 1419.Idem, ibid., p. 2168COLLINSON, DAINTON, AND IVIN : HOMOGENEOUS SYSTEMS. 53The mechanism of the H202-Ce(1v) reaction in sulphate media is claimedto be : 196It is concluded that the system is a source of HO, radicals only, though noindependent checks on the absence of hydroxyl radicals appear to have beenmade.The rate of decomposition of hydrogen peroxide catalysed by the copper-ammonia complex is a maximum at a ratio NH, : Cu = 4 - 5 : 1. Thecatalysis may be due to co-ordinated hydroxyl groups in the complex.197Reactions of Oxygenated Anions.-The mechanism of oxidation by per-manganate proves to be of perennial interest.A very useful analysis hasbeen presented by Drummond and Waters,lQ8 who have attempted toelucidate the stages in the overall change, MnO,- + 8H+ + 5e --+ Mn2+ +4H20, by determining the effect of isolated valency changes on differentorganic groups. In alkaline solution all organic compounds except ethers,saturated carboxylic acids, and tertiary monohydric alcohols are oxidised atthe MnO,- _t MnO," stage. Some of the compounds oxidised cannot beoxidised by hydroxyl radicals and it is concluded, contrary to the views ofother investigator~,l9~9 200 that the hydroxyl radical plays no part a t thisstage. The oxidising action of alkaline permanganate is considered to bedue to a strong tendency of the MnO,- ion to abstract an electron froma substrate.The Mn(m) __t Mn(I1) stage is not capable of oxidisingolefins, formic acid, or alcohols other than 1 : 2-glycols. The mechanism ofoxidation at this stage involves a single-electron transfer of the typeRH + Mn3+ _t R* + Mn2+ + H+, resulting in the production of anactive free-radical R-, which is capable of initiating polymerisation or ofreducing mercuric chloride.2o1 The oxidation of pinacol in this manner hasbeen elucidated inPersulphate oxidations have been the subject of a number of studies.A heterolytic cleavage S,O,' +, SO, + SO,= is suggested as the first stepin the uncatalysed reaction, and the mechanism is capable of giving a fullinterpretation of the oxidation of thiols.2*3 The behaviour of the sulphateradical with water is assumed to be SO, + H20 __t HO+ + H+ + SO,=,followed by HO+ + H20 _t H30+ + 0.A similar suggestion has beenmade to explain the kinetics of the oxidation of formate and formic acid.204I n this case the initial step postulated is S,O,= + H,O _+ SO,= + HSO,- +OH+. The nature of the catalytic oxidation processes with persulphate andmetal ions (especially silver ions) is still not fully understood. The Ag3+ ion,the OH radical, the SO,- ion, and indeed the SO, radical and OH+ ion mayall play a part. Two classes of reaction have been found to exist, viz.,(i) oxidative coupling and (ii) oxygenation, and it is suggested that type (ii)may well occur via hydroxylati~n.~~~H,O, + Ce4+ __t HO, + H+ + Ce3+; HO, + Ce4+ .- 0, + H+ + Ce3+lS6 S.Baerand G. Stein, J., 1953,3176.Is* A. Y. Drummond and W. A. Waters, J., 1953, 435.19s M. C. R. Symons, Research, 1953, 6, 55.zoo F. R. Duke, J . Amey. Chem. SOC., 1948, 70, 3975.2ol A. Y. Drummond and W. A. Waters, J., 1953, 2836.202 Idem, ibid., p. 3119.204 S. P. Srivastava and S. Ghosh, 2. fihysikal. Chem., 1953, 802, 191, 198.,05 R. G. R. Bacon, R. W. Bott, J. R. Doggant, R. Graime, and D. J. Munro, Chem.and Ind., 1953, 897; R. G. R. Bacon and R. W. Bott, ibid., p. 1285.lS7 B. Kirson, Bull. SOC. chim., 1952, 957.203 L. S. Levitt, Canad. J. Chem., 1953, 31, 91554 GENERAL AND PHYSICAL CHEMISTRY.Neptune and King206 have shown that the reaction between the iodideion and selenious acid involves the formation of two activated complexes buta single reaction path.Reactions of Complex Ions.-Basolo 207 has published a review of thestereochemistry and reaction mechanisms of sexicovalent inorganic com-plexes.The factors controlling the steric course of substitutions at octa-hedrally co-ordinated centres are as yet unknown. In a full analysis of theproblem and its difficulties 208 Ingold and his co-workers conclude thatmany of the present structural assignments are suspect because of possiblestereo-changes involved in the conversions forming the basis of the assign-ment. A survey of the literature suggests the possible co-existence ofbimolecular and unimolecular mechanisms ( S N 2 and &1), with perhapsintermediate or quite different mechanisms also. The nucleophilic substitu-tion of chlorine from the cis-dichlorobisethylenediaminecobalt (111) ion hasbeen studied in methyl alcohol as a solvent.209 Four weakly nucleophilicanionic substances reacted by an S N 1 mechanism, whilst three other, morestrongly nucleophilic, substances reacted by an S~2-type mechanism.Theresults are considered to justify an extension of the dual mechanism, so wellestablished for substitutions at the carbon atom, to substitutions on cobaltand to octahedral substitutions generally. I t has further been shown 210that the optically inactive quinquecovalent ion formed in the first stage cantake up the substituting ion at comparable rates in all positions. A tri-angular bipyramidal structure is favoured for this ion. Pearson, Boston,and Basolo 211 have continued their investigation of the kinetics of aquationof cobalt complexes with different bidentate groups.In every case theyfound an S N 1 mechanism. However as the solvent was always water thereis some doubt as to the correctness of this interpretation.208 A tetragonalbipyramidal intermediate has been suggested in the substitution reactionsinvolving chloronitrobisethylenediaminecobalt (111) ion in aqueous solu-tion.212 Tracer studies with I 8 0 have shown that there is a gradual changeof the position of bond fission in hydrolyses of compounds of the type[R-CO2*Co(NH,),]2+ as the group R changes.213 For R = Me the Co-0 bondis broken; whilst for R = CF, the C-0 bond is broken. Aquation of theion never leads to breakage of the C-0 bond.Davis and Dwyer 214 conclude from their experiments on the racemisationof the optically active tris-1 : 10-phenanthrolinonickel salts in water thatthe first step in the unimolecular reaction does not involve bond breakagebut merely a distortion of octahedral configuration.Their reasons forreaching this conclusion have been disputed215 and it has been suggestedthat both for this ion and for the tris-2 : 2’-dipyridyl-Ni2+ ion the first stepin racemisation is dissociation. Davis and Dwyer have also studied theA species of Se(I1) acts as an intermediate.Io6 J. A. Neptune and E. L. King, Chem. and Ind., 1953, 3069.207 F. Basolo, Chem. Reviews, 1953, 52, 459.zo8 D. D. Brown, C. K. Ingold, and R. S. Nyholm, J., 1953, 2674.209 D.D. Brown and C. K. Ingold, J . , 1953, 2680.211 R. G. Pearson, C. R. Boston, and F. Basolo, J . Amer. Chem. Soc., 1953, 75, 3089.112 G. Basolo, B. D. Stone, J. G. Bergmann, and R. G. Pearson, U.S. Atomic En.213 C . A. Bunton and D. R. Llewellyn, J . , 1953, 1692.*14 N. R. Davis and F. P. Dwyer, Trans. Faraday SOL, 1952, 48, 244.215 F. Basolo, J. C. Hayes, and H. M. Neumann, J . Amer. Chem. S t . , 1953, 15, 5102.D. D. Brown and R. S. Nyholm, J., 1953, 2696,Commiss. Report, 1953, AECU-2476COLLINSON, DAIXTON, AND W I N : HOMOGENEOUS SYSTEMS. 55rates of racemisation of optically active complexes of both iron and nickel.216The values of the temperature independent factor in the expressions forthe rate constants are of the expected order for unimolecular reactions inwhich the entropies of the initial and activated states are comparable.Thereaction rates of the first transition series metal ions with 1 : 10-phen-anthroline have been classified, and deviations from recent theoreticalapproaches discussed.217Other Reactions in Solution.-Most of the many studies of the kinetics oforganic reactions in solution have followed conventional lines. A fullre-examination of Hammett’s equation has been made,2f8 and it has beenextended to include many other types of system not previously con-sidered.218* 219 Theoretical treatments of the constants p 220 and a 221 havebeen advanced.The activation energies of two Diels-Alder syntheses involving butadienehave been found to be larger than those of similar reactions with cyclo-pentadiene.222 The suggested explanation for this is that the double bondsof the open-chain and the cyclic diene are respectively trans and cis.An investigation of the rate of iodination of acetone 223 showed that thereactive enol form was probably produced by a ternary mechanism.After astudy of the general consequences of such a mechanism in the light of experi-mental evidence, these authors conclude that, contrary to Swain’s ideas,224ternary mechanisms are not of major importance in reactions catalysed byacids and bases.The acid-catalysed hydrolysis of NN-benzylideneaniline in methane-water solution (50/50) is exceptional in that Hammett’s equation cannot beapplied to the behaviour of its para-substituents, and the dependence of therate on the hydrogen-ion concentration is The experimentalmethod was checked with diazoacetic ester, which showed typicalbehaviour.226The theory of ion-dipole reaction mechanisms has been confirmed forthe hydrolysis of ethyl acetate 227 and of methyl propionate,228 both of whichproceed by such a mechanism.Evidence for quantum-mechanical leakage in proton-transfer reactions atlow temperature has been sought by studying the reactions of the ethoxideion with trinitrotoluene 229 and tris-~-nitrophenylmethane.230 In neithercase did the expected deviation from the Arrhenius relation arise.Bell and Pearson have shown that proton transfers to or from oxygenand nitrogen will normally be too fast for direct observation.2312 l 6 N.R. Davis and F. P. Dwyer, Trans. Faraday SOL, 1953, 49, 180.217 D. W. Margerum and C. V. Banks, U.S. Atomic En. Commiss. Report, 1-853,228 H. H. Jaffe, Chem. Reviews, 1953, 53, 191.219 Idem, Science, 1953, 118, 246. 220 Idem, J . Chem. Phys., 1953, 21, 415.221 F. L. J. Sixrna, Rec. Trav. chim., 1953, 72, 673.222 B. Eisler and A. Wassermann, J., 1953, 979.Z23 R. P. Bell and P. Jones, J., 1953, 58.224 C. G. Swain, J . Amer. Chevn. SOC., 1950, 72, 4578.225 A. V. Willi and R. E. Robertson, Canad. J. Chem., 1953, 31, 361.226 Idem, ibid., p. 493.227 P. M. Nair and S. V. Anantakrishnan, Proc. Indian Acad. Sci., 1952, 32, A , 330.228 J. L. Hockersmith and E. S. Amis, Analyt. Chim. A G ~ u , 1953, 9, 101.29s E. F. Caldin, G. Long, and F. W.Trowse, Nature, 1953, 171, 1124.230 E. F. Caldin and J. C . Trickett, Trans. Faraday SOG., 1953, 49, 772,esl R. P. Bell and R. G. Pearson, 1.. 1953, 3443.ISC-36656 GENERAL AND PHYSICAL CHEMISTRY.Isotope Effects.-Ropp 232 has reviewed investigations made between1948 and 1952 of the effect of isotopic substitution on organic reaction rates.In an earlier calculation of the relative velocities of reactions involvingisotopic molecules, Bigeleisen considered only simple bond rupture or form-ation pro~esses.23~ An expression has now been derived for simultaneousbond rupture and formation in reactions involving carbon isotopes.234Investigations which have recently been found to give results in agree-ment with theoretical predictions include the ozonisation of [a-14C]stilbene,235the non-enzymic hydrolysis of urea 236 (in contrast to the enzymic hydrolysis),and the reaction of formaldehyde with dimed~ne.~~' In addition, Bigeleisenand Wolfsberg 238 claim that Ropp and Raaen's results on decarboxylationare consistent with a 14C-isotopic effect which, as predicted by theory, istwice that of 13C.On the other hand several investigations have produced results which donot agree with theoretical predictions. Thus Yankwich and Stivers 239find that although the magnitude of the intramolecular 13C-isotope effect inthe decarboxylation of malonic and bromomalonic acids conforms to theory,the 14C effect is markedly greater than expected. A ratio of the two effectsas high as 4.8 -& 0.9 has been found for the bromo-acid.Ropp, Raaen, andWeinberger 240 find an unexpectedly high isotope effect in the decompositionof mercurous [14C]formate, and a complete lack of effect, for which there isno obvious explanation, in certain addition reactions. In both the ethan-olysis of [~-~~C]benzoic anhydride and its reaction with #-toluidine 241 theintramolecular isotope effects agree with theory inasmuch as they show nochange with change of temperature. The actual values are, however, verydifferent from theoretical expectations. Pitzer and Gelles 242 have suggestedthat anomalous results with carbon isotopes may be due in part to themagnetic properties of 13C.Bigeleisen's theory has been so successful in explaining isotope effects indecarboxylation reactions that when exceptions are found in such cases thetendency is to use this information as a guide to peculiarities of mechanism.The magnitude of the intermolecular 13C-isotope effect in the decarboxylationof malonic acid in 80% sulphuric acid was found to be in accord with theory,but the temperature dependence was not.243 For the same decarboxylationin quinoline neither the magnitude nor the temperature variation was thatexpected.244 A combination of isotopic data with kinetic data indicates thatthe mechanism comprises a solvation equilibrium followed by a bimoleculardecomposition of the complex.Isotopic fractionation has also been usedas a method of studying the mechanism of the decarboxylation of barium233 G. A. Ropp, Nucleonics, 1952, 10, (lo), 22.233 J. Bigeleisen, J .Chem. Phys., 1949, 17, 675; J. Phys. Chem., 1952, 56, 823.234 J. Bigeleisen and M. Wolfsberg, J . Chem. Phys., 1953, 21, 1972.235 A. Bonner and C. J. Collins, J . Amer. Chem. Soc., 1953, 75, 3693.236 J. A. Schmitt and F. Daniels, ibid., p. 3564.237 A. M. Domes, Austral. J. Sci. Res., 1952, 5, A, 521.238 J. Bigeleisen and M. Wolfsberg, U.S. Atomic En. Commiss. Report, 1953,240 G. A. Ropp, V. F. Raaen, and A. J. Weinberger, J . Amer. Chem. Soc., 1953, 75,242 K. S. Pitzer and T. E. Gelles, J . Amer. Chem. Soc., 1953, 75, 5132.243 P. E. Yankwich, R. L. Belford, and G. Fraenkel, ibid., p. 832.244 P. E. Yankwich and R. L. Belford, ibid., p. 4178.BNL- 1487.3694.23D P. E. Yankwich and E. C. Stivers, J .Chem. Phys., 1953, 21, 61.241 V. F. Raaen and G. A. Ropp, J . Chem. Phys., 1953, 21, 1902COLLINSON, DAINTON, AND IVIN : HOMOGENEOUS SYSTEMS. 57a d i ~ a t e , ~ * ~ and it has been suggested that applied to hydrogen isotopes themethod may be used to detect hyperconjugation in the transition ~ t a t e . 2 ~ ~Fractionation of the oxygen isotopes indicated that the hydroxyl radical isnot the sole primary product in the photolysis of hydrogen per0xide.~*7Condensation Polymerisation.-Papers have been published on the kin-etics of polycondensation of 1 l-aminoundecanoic acid 248 and of adipicacid with pentane-1 : 5-diol in diphenyl ether.249 With the former case thereaction order is two, but in the latter the order is only approximately twoand is not constant.This variable order is discussed in terms of an initialtermolecular activation step. A theory of stepwise polymerisation underpressure has been put forward and applied to the condensation of acetone at3000 atm.250Radical Polymerisation and Depo1ymerisation.-Initiators and InitiationRates.-In this section have been included the kinetics of decomposition ofa number of azo- and peroxy-compounds which have not been used speci-fically as polymerisation initiators but are grouped here for convenience.The rate of decomposition of diacetyl peroxide has been measured ina number of solvents and found to be roughly parallel to the rate of decom-position of dibenzoyl peroxide in these solvents.251 The mechanism of itsdecomposition has also been studied by using [14C]acetic acid as solvent.252The work of Volman and Graven 253 on the photochemical decomposition ofdi-tert.-butyl peroxide vapour between 30-120" is in substantial agreementwith earlier results.The effect of phenols on the rate of decomposition ofdibenzoyl peroxide solutions has been shown to be complex.254 The effectof substituents on the rate of decomposition of substituted dibenzoyl per-oxides in styrene and on the rate of the induced polymerisation have beenfurther investigated.255Cooper256 has examined 11 hydroperoxides as initiators for the poly-merisation of styrene at 70". Apart from more rapid initiation due to arylgroups, changes of structure have only small effects on the rate of poly-merisation. The thermal decomposition of cyclohexenyl hydroperoxide hasbeen investigated in a number of hydrocarbon s0lvents.2~7.258 In olefins,at concentrations > 0.03 M, decomposition takes place by a chain mechanisminvolving the solvent, the initiation process being of second order withrespect to the peroxide. In benzene the chain process is suppressed almostcompletely and the decomposition approximates to a one-stage second-orderreaction. At very low concentrations ( < 0.02 M) , the hydroperoxide decom-poses mainly by a first-order process. Decalin hydroperoxide also decom-poses by a first-order chain-reaction in this concentration region, and the245 J. Bigeleisen, A. A. Bothner-By, and L. Friedman, J . Amer. Chem. Soc., 1953,246 E. S. Lewis and C.E. Boozer, ibid., 1952, 74, 6306.247 J. P. Hunt and H. Taube. zbid., p. 5999.248 R. Vergoz, Ann. Chim., 1953, 8, 101.249 M. Davies and D. R. J. Hill, Trans. Faraday SOL, 1953, 40, 395.251 W. M. Thomas and M. T. O'Shaughnessy, J . Polymer Sci., 1953, 11, 455.252 A. Fry, B. M. Tolbert, and M. Calvin, Trans. Faraday Soc., 1953, 49, 1444.z53 D. H. Volman and W. M. Graven, J . Amer. Chem. SOG., 1953, 75. 3111.254 J. J. Batten and M. F. R. Mulcahy, Nature, 1953, 172, 72.255 M. Takebayashi and T. Shingaki, Bull. Chem. Soc., Japan, 1953, 26, 137.256 W. Cooper, J . , 1953, 1267. 257 L. Bateman and H . Hughes, J., 1952, 4594.258 L. Bateman, H. Hughes, and A. L. Morris, Discuss. Faraday SOL, 1953, 14, 190.75, 2908.M. G. Gonikberg, Chem. Abs., 1953, 47, 38958 GENEKAL AND PHYSICAL CHEMISTRY,energy of activation has been determined in several ~olvents.2~9 The photo-chemical decomposition of tert.-butyl hydroperoxide in carbon tetrachlorideand in n-hexane proceeds by a short chain mechanism yielding tert.-butylalcohol, oxygen, and small amounts of other compounds.260 In dioxan thechains are not able to propagate owing to the reactivity of the solvent, anda quantum yield of I is found.260The kinetics of the first-order decompositions of azo-compounds of thetype fi-X*C,H4*N2*CPh, have been investigated, and the results compared withthose on the decomposition of similarly substituted peroxy-compounds.261N-Nitrosoacetanilide has been shown to initiate radical polymerisation.262Tobolsky and Baysal 263 have correlated much of the published data on thecatalysed bulk polymerisation of methyl methacrylat e and styrene, respec-tively.If the rate of decomposition of the catalyst (C) is given by 2Ki[C]and the rate of initiation of polymer chains is given by Ri, then the catalystefficiency f may be defined as f = &/Zki[C], lOOyo efficiency correspondingto two polymer chains initiated per catalyst molecule decomposed. It isreadily shown that, for a system in which transfer to catalyst and thermalinitiation are negligible, f = K1K2/ki(l + x), where K , and K2 are thetemperature-dependent constants in the experimental relationshipsl/Fn = I< + K1Rp/[M]2 and lip = K2[M][C]iand R, is the rate of polymerisation for monomer concentration [MI, Fpt isthe mean degree of polymerisation of the polymer formed, and x = Ktd/(ktd +&).KM and Kt, are the velocity constants for termination by dispropor-tionation and combination, respectively. In spite of the work by Arnett,264the value of x for methyl methacrylate cannot be said to be settled. Arnettconcluded that x = 0 andf = 0.5, but this does not fit in withf = 0-94/(l +x ) , derived from the equation above,263 or with new polymer-degradationevidence 265 which indicates a value of x close to 1 (see below).Further light has been thrown on the question of diradical polymerisationby a study of the inhibition of the thermal polymerisation of styrene by2 : 2-diphenylpicrylhydrazyl and benzoquinone.266 It now appears probablethat in the absence of inhibitors, a growing diradical will cyclise very readily,SO that only those diradicals which are converted into monoradicals beforecyclisation can occur, will, in fact, give rise to high polymers.The validity of current methods of determining Ri from retarder experi-ments has been examined by detailed kinetic analysis.267Polymerisation of Single Monomers.-The polymerisation of butadiene inthe gas phase, initiated by radicals from the photolysis of di-tert.-butylperoxide and acetone, has beenIn the polymerisation of styrene, chain-transfer constants have beendetermined for 12 solvents268 and a number of organic compounds.269259 C .F. H. Tipper, J., 1953, 1675.260 J . T. Martin and R. G. W. Norrish, PYOC. Roy. SOC., 1953, A, 220, 322.261 S.G. Cohen and C. H. Wang, J. Amer. Chem. SOC., 1953, 75, 5504.262 D. F. Detar and C. S. Savat, ibid., p. 5716.263 A. V. Tobolsky and B. Baysal, J . Polymer Sci., 1953, 11, 471.264 See An%. Repovts, 1952, 49, 58.265 N. Grassie and E. Vance, Trans. Faraday SOC., 1953, 49, 184.266 K. E. Russell and A. V. Tobolsky, J . Amer. Chem. SOC., 1953, 75, 5052.2 6 7 G. M. Burnett and P. R. E. J. Cowley, Trans. Faraday SOC., 1953, 49, 1490.268 S. I,. Kapur, J. PoZymer. sci., 1953, 11, 399.269 R. A. Gregg and F. R. Mayo, J . Amer. Chem. SOC., 1953, 75, 3530COLLINSON, DAINTON, AND WIN HOMOGENEOUS SYSTEMS. 59That chain transfer with disulphides occurs by a process of the type :P, + RSSR’--t P;SR + R’S, has been confirmed by the fact thatcyclic disulphides become copolymerised with both styrene 270 and vinylacetate.271The order with respect to monomer has been determined for the catalysedpolymerisations of methyl methacrylate, vinyl acetate, and vinyl chloridein various solvents.272 For methyl methacrylate in benzene the normalorder of one is found; for other systems observed orders of 1-5 and variableorders are interpreted in terms of complex formation between monomer andcatalyst.Polymethyl methacrylate has been shown to initiate polymeris-ation of its monomer ; but addition of the same polymer to other monomersor of other polymers to methyl methacrylate does not induce polymeris-ation.273Further information concerning the termination step in methyl meth-acrylate polymerisation has been obtained by two methods.274, 275 Both setsof results support disproportionation, as opposed to combination, of twopolymer radicals as the termination step.However the first method, inwhich rate and molecular-weight measurements of the retarded and un-retarded reactions are compared, is admitted by the authors to be somewhatambigu0us.~~4 The second method depends upon a comparison of the ratesof degradation of polymers made by bulk polymerisation and by polymeris-ation of the monomer in benzene.275 The results are interpreted on theassumption that initiation of degradation occurs most easily at the double-bond end structure, formed when two polymer radicals terminate by dis-proportionation. There will be fewer such end structures in the polymerprepared in solution owing to the occurrence of chain transfer with thebenzene, and accordingly, lower rates of degradation are observed.How-ever, it should be noted that when vinyl acetate is polymerised in labelledbenzene, a small amount of solvent becomes incorporated into the polymerby copolymerisation rather than through the transfer pr0cess.2~~ Thepossible effect of traces of copolymerised benzene on the rate of degradationis thus an uncertain factor in the work described above.The equilibrium pressure of monomer over polymethyl met hacrylate hasbeen measured at various temperatures; 277 the results lead to values for theheat and entropy of polymerisation in reasonable agreement with calorimetricand kinetic data. Magnetic studies have thrown some light on the modeof action of retarders in the catalysed polymerisation of methyl meth-a ~ r y l a t e .~ ~ * The velocity constants for the bulk polymerisation of n-butyland n-propyl methaccylate have been compared with those for the poly-merisation of the methyl ester.279Evidence for a monomer-termination process has been obtained in theNo satisfactory explanation of this phenomenon has been found.270 A. V. Tobolsky and B. Baysal, J . Amer. Chem. SOC., 1953, 75, 1757.271 W. H. Stockmayer, R. 0. Howard, and J. T. Clarke, ibid., p. 1756.272 A. Conix and G. Smets, J . Polymer. Sci., 1953, 10, 525.273 H. W. Melville and W. F. Watson, ibid., p. 299.274 E. P. Bonsall, L. Valentine, and H. W. Melville, Trans. Faraday SOC., 1953, 40, 686.275 N.Grassie and E. Vance, ibid., p. 184.278 W. H. Stockmayer and L. H. Peebles, J . Amer. Chem. SOC., 1953, 75, 2278.277 P. A. Small, Trans. Faraday Soc., 1953, 49, 441.278 J. L. Ihrig and H. N. Alyea, J . Amer. Chem. SOC., 1953, 75, 2917.27s G. M. Burnett, P. Evans, and H. W. Melville, Trans. Faraday SOC., 1953, 49,1096, 110560 GENERAL AND PHYSICAL CHEMISTRY.catalysed polymerisations of ethyl acrylate,280 vinyl benzoate,281 and ally1[2HJacetate.282 Mutual termination is indicated in the case of vinyl pro-pionate.28lThe methacrylate ion has been shown to polymerise in aqueous solutionat a rate much smaller than that of the undissociated The kineticsof the polymerisation of aqueous methyl acrylate and acrylonitrile have beeninvestigated, initiation being effected by P-nitrobenzenediazo-radicals.284Three kinetic investigations have been made on bulk polymerisations inwhich the polymer is insoluble in the 286, In common withvinyl chloride, vinylidene chloride 285 and acrylonitrile exhibit a steadilyincreasing polymerisation rate, due to catalysis by the precipitated polymer.Bamford and Jenkins suggest that growing radicals become occluded inpolymer aggregates during polymerisation, so reducing kb and, under severeconditions, k, also.It is interesting to note that polyvinylidene chlorideloses its catalytic activity on exposure to air, and that polyacrylonitrileprepared at room temperature is able to initiate the polymerisation ofseveral monomers at higher temperatures.An exploratory investigationof the kinetics of polymerisation of chlorotrifluoroethylene both in bulk andin solution has revealed no such complexities.251CopoZymerisatiout.-Relative reactivity ratios have been determinedfrom monomer-polymer composition relations for a number of monomerpairs,251127g~287-291 and in some cases Q and e values have been de-287-289 The copolymerisation behaviour of methacrylic acid bothwith diethylaminoethyl methacrylate and with acrylonitrile dependsmarkedly on the pH of the polymerising system.289 This is attributed toa distinctive copolymerisation behaviour of the methacrylate ion. Thecompositions of copolymers made from mixtures of three monomers havebeen found to be in fair agreement with predictions based on the relativereactivity ratios of the two component systems.290 It has been shownthat the variation with pressure in the composition of the copolymer formedfrom ethylene and carbon monoxide at high pressure can be explained byassuming that a 1 : 1 complex is one of the effective mon0mers.2~4Bengough and Norrish 291 have measured the rate of copolymerisation ofvinyl chloride with vinylidene chloride, catalysed by dibenzoyl peroxide.They were able to measure the rate of consumption of each monomer bymeans of an ingenious device for following continuously the change of vapourpressure of the monomer mixture.The overall rate passes through aminimum as the composition is varied and increases with time at all com-positions. In the system styrene-maleic anhydride-solvent there is a rangeof composition over which the polymer remains in solution but outside which280 H.Sumitomo and Y . Hachihama, Chem. Abs., 1953, 47, 10318.281 G. M. Burnett and W. W. Wright, Trans. FaradQy SOL, 1953, 49, 1108.282 P. D. Bartlett and F. A. Tate, J . Amer. Chem. SOC., 1953, 75, 91.283 G. Blauer, J . Polymer Sci., 1953, 11, 189.284 W. Cooper, Chem. and Ind., 1953, 407.285 W. I. Bengough and R. G. W. Norrish, PYOC. Roy. SOC., 1953, A , 218, 149.286 C. H. Bamford and A. D. Jenkins, ibid., 1953, A, 216, 515.287 S. H. Pinner, J . Polymer S C ~ . , 1953, 10, 379.288 C. C. Price and H. Morita, J . Amer. Chem. Soc.. 1953, 75, 4747.280 T. Alfrey, C. G. Overberger, and S. H. Pinner, ibid., p. 4221.200 S.L. Aggarwal and F. A. Long, J . Polymer Sci., 1953, 11, 127.291 W. I. Bengough and R. G. W. Norrish, PYOC. Roy. SOC., 1953, A , 218, 155COLLINSON, DAINTON, AND IVIN : HOMOGENEOUS SYSTEMS. 61it is precipitated. Bamford and Barb292 have studied the kinetics in thetwo regions and find in the homogeneous region a steady rate and catalystexponent of 0-5, whereas in the heterogeneous region there is an increasein rate with time and a catalyst exponent greater than 0-5. It is concludedthat the stationary state treatment is inapplicable to such heterogeneoussystems. Barbzg3 has concluded that certain abnormalities in the com-positional relationship of styrene-maleic anhydride copolymers indicate thatnon-terminal monomeric units in a polymer radical can detectably influencethe radical reactivity.Kinetic studies have been made on the copolymerisation of methylmethacrylate with ethylidene dimetha~rylate.~~~ The degree of branchingof the polymer can be expressed as a function of the extent of reaction.Barb z97 has deduced the values E d = 12-15 kcal./mole, A d = 4 x l0-lo-3 x 10-l2 sec.-l for the depropagation process in the copolymerisation ofstyrene with sulphur dioxide.DepoZymerisation.-In the past, rates of degradation have generally beenmeasured by determining either the rate of evolution of volatile products orthe rate of loss in weight when the polymer is heated in vacuo, and suchmethods continue to be e r n p l ~ y e d .~ ~ ~ ~ 298 However, the results can only beof real value when the overall stoicheiornetry is known.Past and presentmeasurements have shown that only in a few cases does a polymer degradecleanly to monomer, and the formation of other products must be taken intoaccount in any detailed mechanism. The application of direct mass-spectrographic methods of analysis of the volatile products promises toclarify the interpretation of experimental data.300 Thus from a series ofmeasurements on polystyrene between 260" and 330", in which less than 1%of the sample was degraded in each experiment, energies of activation of65, 57, and 56 kcal./mole have been found for the rate of production ofstyrene, benzene, and toluene, r e s p e c t i ~ e l y . ~ ~ Dimers, trimers, tetramers,and pentamers are also produced.301 Velocity constants have been deter-mined for the initiation and propagation processes in the molecular chainelimination of acetic acid from polyvinyl acetate.302 The kinetics andproducts of thermal degradation of polyethylene terephthalate have beenexamined over a range of temperature; the results are consistent with aninitial random chain scission.303Grassie304 has reviewed the work on the degradation of polymethylmethacrylate.An extension of this work has been referred to earlierSimha 305 has applied his general treatment of degradation chain mechan-isms to the particular case of terminal initiation and absence of transfer.(Pa 59).Z s 2 C. H. Bamford and W. G. Barb, Discuss. Faraday SOC., 1953, 14, 208.Zs3 W. G. Barb, J . Polymer Sci., 1953, 11, 117.204 W.G. Barb, J . Amer. Chem. SOC., 1953, 75, 224.296 G. Smets and J. Schmets, Bull. SOC. chim. Belg., 1953, 62, 358.z97 W. G. Barb, J . Polymer Sci., 1953, 10, 49.Z s 8 S. L. Madorsky, ibid., 1953, 11, 491.299 H. H. G. Jellinek and K. J. Turner, ibid., p. 353.30° P. D. Zemany, Nature, 1953, 171, 391.301 P. Bradt, V. H. Dibeler, and F. L. Mohler, J . Res. Nut. Bur. Stand., 1963, 50, 201,302 N. Grassie, Trans. Faraday SOC., 1953, 49, 835.3OS I. Marshalland A. Todd, ibid., p. 67. 304 N. Grassie, Chem. undInd., 1953, 022.30s R. Simha, J . Polymer Sci., 1953, 10, 49962 GENERAL AND PHYSICAL CHEMISTRY.Jellinek 306 has considered random initiation and has calculated for variousdegradation mechanisms the initial rates of formation of monomer as afunction of the total weight of polymer, initial molecular weight, etc.Thebreakdown of large free radicals has been discussed in terms of the accom-panying changes of enthalpy and entropy.307 Some preliminary resultshave been given on the effect of olefin structure on the ceiling temperaturesobserved in olefin-sulphur dioxide copolymerisation. In the case of the cis-and the trans-but-2-ene system it has been shown that cis-trans isomerisationaccompanies polymerisation in the region of the ceiling temperature, thusproviding added evidence that the ceiling-temperature phenomenon is causedby the occurrence of depropagation processes.30sMolecular-weight Distribution.-The form of the molecular-weightdistribution curve of a polymer provides a means of checking or determiningthe termination process in a given polymerisation reaction, but its experi-mental determination is not easy and the number of theoretical papers onthe subject continues to exceed the number of experimental papers.Newmethods have been given for the calculation of distribution functions,3099 310and these and other methods 311 have been applied to mechanisms involvingvarious types of termination process. In two experimental papers on themolecular-weight distribution of polymethyl methacrylate prepared by redoxpolymerisation in aqueous solution, it has been shown that at high concen-trations of emulsifying agent, termination occurs mainly by combination,though somewhat different molecular-weight distributions are given bydifferent experimental methods312Ionic Polymerisation.-The proceedings of an informal conference held atStoke in March, 1952, on " Cationic Polymerisation and Related Complexes "have been published.313 No attempt will be made here to review theseproceedings since most of the papers contained therein have been published.Attention will therefore be confined to those papers which have appearedthis year in the normal way.system " may be defined as monomer-catalyst-co-catalyst-solvent.A number of systems are known to requirethe presence of traces of water as co-catalyst in order that polymerisationshall occur, and to these have been added the following: (1) a-methyl-styrene-stannic chloride-water-ethyl chloride ; 314 (2) cis- or traws-stilbene-boron trifluoride- or -titanium tetrachloride-water-carbon tetrachloride orno solvent ; 315 (3) styrene-titanium tetrachloride-water-hexane or toluene ; 316(4) isoprene-stannic chloride-water-no solvent (at - 80" c) .317 However,in the systems : (5) styrene-titanium tetrachloride-X-dichloroethane ordibromoethane ; 316 (6) isoprene-stannic chloride-X-ethyl chloride andsystem (4) at 0" c, 317 it is claimed that a co-catalyst of the normal type ( e g .,In cationic polymerisation a306 H. H. G. Jellinek, J . Polymer Sci., 1953, 10, 457.307 F. S. Dainton and K. J. Ivin, Discuss. Furaday Soc., 1953, 14, 199.308 G. M. Bristow and F. S. Dainton, Nature, 1953, 173, 804.309 W. F. Watson, Trans. Faraduy SOC., 1953, 49, 842, 1369.310 C.H. Bamford and H. Tompa, J . Polymer Sci., 1953, 10, 345.311 D. Tabuchi, Chem. Abs., 1953, 47, 7818, 11798.312 A. F. V. Eriksson, Acta Chem. Scand., 1953, 7, 377, 623.313 Ed. P. €3. Plesch, Publ. W. Heffer and Sons Ltd., Cambridge, 1953.314 F. S. Dainton and R. H. Tomlinson, J., 1953, 151.315 D. S. Brackman and P. H. Plesch, J., 1953,1289.3 1 7 A. R. Gantmakher and S. S. Medvedev, Chena. Abs., 1953, 47, 4713, 4714.s16 P. H. PIesch, J . , 1953,1693COLLINSON, DAINTON, AND IVIN : HOMOGENEOUS SYSTEMS. 63water or trichloroacetic acid) is not required although addition of water doesgreatly increase the rate in system (5). Infra-red absorption of the polymersformed in the system (7) styrene-titanium tetrachloride-trichloroacetk acid-toluene318 shows that a large fraction of the polymer molecules containtolyl end groups but that groups derived from trichloroacetic acid are notincorporated in the polymer.However, in system (5) and similar systemswith alkyl halide solvents the polymer contains initial and end groups derivedfrom the solvent. This is taken to indicate that the co-catalyst X in system( 5 ) , and presumably also in system (6), is in fact the solvent. A solvent maythus act in three ways in ionic polymerisation : by its dielectric effect on theelectrostatic forces, as the co-catalyst, and as a transfer agent.319In system(1) the rate is independent of the co-catalyst-catalyst ratio when this isgreater than 3. The rate is then proportional to [SnCl,][M,]y where yincreases with [M,] from 1-2 to 2.The proposed mechanism involves theusual initiation and propagation processes, with termination by spontaneousproton release, which may be accompanied by cyclisation. With dideuter-ium oxide as co-catalyst, the polymer formed contains C-D bonds. Theinitial rate is lower than with water, but increases until it has the valuecharacteristic of the latter. This effect is ascribed to the gradual conver-sion of the dideuterium oxide into water as reaction proceeds. In system (5)the rate is proportional to [TiCl,][M,]2. In system (2) the polymers formedare mixtures of dimers and trimers. No isomerisation is observed in thesesystems and distinct complexes are formed with titanium tetrachloride alone.The red complex formed during the sodium catalysed polymerisation ofstyrene has been shown to be paramagnetic and the stable radical ion(C,H,*CH=CH,)- has been postulated.320Radiation Chemistry.-Primary Processes.-Lindholm 321 has carried outan interesting investigation of the ionisation of hydrogen sulphide by bom-bardment with electrons and a variety of atomic ions.The relative pro-portions of the ions H,S+ : HS+ : Si from electron bombardment were100 : 43 : 46. For the other bombarding ions the proportions of the differentspecies varied, and in many cases the mass spectrum was simpler than forelectron bombardment. Of particular interest are the results of the bom-bardment by rare-gas ions, where the ions HS+ and S+ invariably occur ingreater amounts than does H,S+.The energy of the ions (500 ev) was ofcourse low compared with energies used in typical radiation chemical studies,but the differences between the electron results and the results for heavyions arouse a long standing suspicion that some of the differences found for,say, or-particle irradiations and electron irradiations in water may be due todifferences of primary product as well as to the much discussed ion-densityeffect.Radiation Sources and Actinometry.-The reliability of radioactive iso-topic sources and their increasing availability are factors causing this typeof source to replace machines for experiments with photon radiations. Forsuch sources a disc shape offers the greatest general effi~iency,~~2 but hollowDetailed kinetics have been obtained for systems (1) and (5).318 P.H. Plesch, J., 1953, 1659.320 D. Lipkin, D. E. Paul, J. Townsend, and S. I. Weissmann, Science, 1953, 117, 534.321 E. Lindholm, Proc. Phys. SOC., 1953, 66, A, 1068.322 M. Brucer, W. G. Pollard, H. Leiter, and H. Scarf, Xucleonics, 1963, 11 (2), 38.319 Idem, ibid., p. 166264 GENERAL AND PHYSICAL CHEMISTRY.cylinders have also been 324 The 60cobalt isotope is at presentthe most popular for y-irradiations, but several others have been proposed.Freundlich and Haybittle 325 have used an 192iridium teletherapy unit.Manowitz 324 describes a source of 182tantalum, and other practicable y-sourcesare 152-154e~r~pi~m, 137caesium, and 144cerium.326The energy yield for the ferrous sulphate-0-8~-sulphuric acid system usedin actinometry remains uncertain.As the uncertainty appears to arise fromthe physical rather than from the chemical side, it is reasonable to assumethat all other chemical actinometers are virtually in the same position. Ayear ago a value of G(Fe2+),,,kd = 20 seemed to be favoured, but since thenthere has been an ever increasing indication that the value of G = 15.5 ismore nearly correct. Much of the relevant work has yet to be published.In all, four methods have been employed for measurement of the energyabsorbed to produce a given change. These are ionisation measurements,calorimetry, charge measurements with electron beams, and absolute count-ing methods with radioactive isotopes. Miller,327 using an ionisation methodto measure the energy absorbed, has carried out experiments with X-radi-ation, of energy between 1-5 and 2-25 Mv, and has found a constant yield,G = 20.3 & 1.0, for dose rates up to 100,000 r/min. Ebert and Boag328obtained the same result in similar experiments, and Magat and Chapiro 328have also found a similar value.Hummel and S p i n k ~ , ~ ~ ~ using less rigorousmethods of relating ionisation measured to energy absorbed, found G = 16.8for radium y-rays, and G = 15-8 for betatron X-rays of energy 24.5 Mvp.For 60Co y-radiation a value of G = 17.4 was found.330Two results based on calorimetric measurements have appeared : Davisonet aZ.331 found G = 20, whilst Hochanadel and Ghormley332 found G =15-6 & 0.3, both for 6oCo radiation. Hochanadel and Ghormley also usedan ionisation method and obtained G = 16.7, but in the geometry of theirexperiments the Bragg-Gray conditions were not fulfilled.By measure-ment of the charge-input for 1.33-Mev Van de Graaff electrons they obtainedG = 16.8 & 0.3, the difference from their calorimetric result being due toundetermined back-scatter. Amphlett 333 found G = 17 by the samemethod. A more rigorous measurement of this type has recently been madeby Saldick and Allen 334 who found G = 15.6 5 0-5. Minder 335 has studiedthe effect of a mixed source of s6Rb and 35S in solution; the energy absorp-tion was calculated from known constants and the geometry of the system,and the result obtained was G = 14.6 I;t 0.3. By using 6oCo, and againcalculating the absorbed energy, he obtained G = 14.4 & 0.2. Taken as awhole the results for ferrous sulphate actinometry seem to indicate that a323 D.F. Saunders, F. F. Morehead, and F. Daniels, J . Amer. Chem. Soc,, 1953, 75,325 H. F. Freundlich and J. L. Haybittle, Acla Radzologica, 1953, 39, 231.326 T. Leucutia, Amer. J . Roentgenol., 1953, 69, 108.327 N. Miller, Nature, 1953, 171, 688.328 R. W. Hummel and J. W. T. Spinks, Canad. J . Chem., 1953, 31, 250.330 G. R. Freeman, A. B. van Cleave, and J. W. T. Spinks (see ref. 329).331 S. Davison, S. A. Goldblith, B. E. Proctor, M. Karel, B. Kan, and C . J . Bates,332 C. J. Hochanadel and J. A. Ghormley, J . Chem. Phys., 1953, 21, 880.333 C. B. Amphlett, Discuss. Faraday SOC., 1952, 12, 272.334 J.Saldick and A. 0. Allen, to be published.335 W. Minder, Helv. Phys. .A&, 1953, 26, 407.3096. 324 B. Manowitz, Nucleonics, 1953, 11 (3), 18.328 See ref. 327.Nucleonics, 1953, 11 (7), 22COLLINSON, DAINTON, AND W I N : HOMOGENEOUS SYSTEMS. 65value of G = 20 is obtained by rigorous ionisation-measurement methods,whilst a value of G = 15.5 is obtained by rigorous calorimetric or charge-counting methods. Although flaws have been sought in all aspects ofthese techniques, they have not been found in sufficient magnitude toexplain the difference of 30y0.336A new method of measuring the conversion of ferrous into ferric ion forthe ferrous sulphate actinometer has been proposed; 337 this consists of theuse of 59Fe as a tracer and the measurement of the radioactivity of theFe(rr1) formed.I t is claimed that doses in the range 0-100 r can be measuredwith an accuracy of &2 r.Non-aqueous Vapcur and Liquid Systenzs.-Despite the evident complexityof such work, an appreciable number of investigations of the chemical effectproduced in electric discharges have appeared. Yields of product withrespect to electrical energy input have generally been determined undervarying conditions and in some cases mechanisms have been proposed. Theuse of deuterium in the study of the decomposition of methane has proveduseful in this respect .338 Other investigations include the decomposition ofcarbon dioxide,339 met hane,340 a m m ~ n i a , ~ ~ l l 344 and hydrogen peroxide,342 theproduction of ozone,343 reactions of toluene and ben~ene,3~4 and the oxidationof ethanol 345 and benzene.346The decomposition of carbon dioxide by ionising radiations is a t leastpartly heterogeneo~s.~4' The exchange reaction between tritium andhydrogen gas brought about by the p-radiation of tritium itself has beenfound to be a chain reaction, the rate of which is proportional to the squareroot of the intensity of theSchuler and his co-workers have investigated the radiolyses of liquidalkyl halides.349 Comparison of the results for methyl iodide with those forthe photolysis indicates that processes peculiar to radiation chemistry cccur,the importance of ionic processes being apparent.The effect of 60Co y-radiation on the liquid chloroform-oxygen systemhas been examined.350 Analysis of the products was made for differentvalues of temperature, oxygen concentration, and time of irradiation.Though the reaction undoubtedly proceeds by a chain mechanism it has notyet been possible to elucidate this completely.The radiolysis of chloroformhas also been studied with diphenylpicrylhydrazy! as solute.351 This solute336 T. J. Hardwick, Canad. J . Chenz., 1953, 31, 512.337 G. Rodstam and T. Svedberg, Natztre, 1953, 171, 648.338 H. Weiner and M. Burton, J . Anzer. Chem. SOC., 1953, 75, 5815.359 K. A. Wilde, B. J. Zwolinski, and R. B. Parlin, U.S. Atomic En. Commiss. Report,341 K. Ouchi and T. Takamatsu, J , EZectvochem. SOL. Japan, 1953, 21, 75, 132.342 J. S. Batzold, C. Luver, and C. A. Winkler, Canad. J .Chew&., 1953, 31, 2G2.343 E . Brmer, V. Spreter, and B. Kovaliv, Bull. SOC. china. Belge, 1953, 62, 55.344 H. Schiiler and V. Degenhart, 2. Naturforsch., 1952, 'Sa, 763.345 R. H. Sahasrabudhey, S. M. Deshpande, and R. V. G. Rao, Proc. Iizdian Acad.346 J. C. Chu, H. C. Ai, and D. F. Othmer, Ind. Eng. Ckenz., 1953, 45, 1266.347 S. Dondes and A. J. Hogan, U.S. Atomic En. Commiss. Report, 1953, SO-3251.348 L. M. Dorfman and 13. C. Mattraw, J . Phys. Chem., 1953, 57, 723.349 R. H. Schuler and W. H. Hamill, ibid., 1952, 74, 6171; R. C. Petry and R. H.360 J. W. Schulte, J. F. Suttle, and R. Wilhelm, J . Anzer. Chenz. SOC., 1953, 75, 2222.361 A. Chapiro, J. W. Boag, M. Ebert, and L. H. Gray, J . Chinz. $hys., 1953, 50, 468.1953, AECU-2582. 340 R.Miquel, B.ul1. SOL. chim., 1053, 970.Sci., 1952, 36, A , 258.Schuler, ibid., 1953, 75, 3796.REP.-VOL. L 66 GENERAL AND PHYSICAL CHEMISTRY.acts as an acceptor of the radicals formed from the solvent, and theresults can be explained on the basis of a mechanism advanced by Daintonand Miller.35Z A very interesting feature of the work, which is developedfurther in another paper,353 is that the effect of dose-rate variation can onlybe explained on the basis of an increasing non-uniformity of radical distri-bution with decreasing dose rate, in the manner already pcstulated foraqueous solutions.354 In agreement with the results for aqueous solutionsthe degree of non-uniformity was found to be independent of the radiatioEquality. Experiments with chloroform and with methyl acetate indicateduniformity of radical distribution for dose rates greater than 250 and1000 r/min., respectively.353Copolymerisations of styrene-methyl methacrylate mixtures have beeninduced by p-irradiati~n.~~~ Subsequent analyses of the copolymers showedthem to contain about equal molecular proportions of each monomer, therebyestablishing that this polymerisation proceeds by a free radical rather thanby an ionic mechanism.If the reaction is homogeneous, only a lowpercentage of the absorbed energy is effective in producing polymerisation.In the y-ray polymerisation of pure acrylonitrile the polymerisation rate isproportional to Rz (where R = dose rate and fr < x < l).356 It is suggestedthat the mechanism involves two termination steps, a bimolecular and aunimolecular step, and it is claimed that the results are explained on thisbasis.However, the experimental results indicate a constant value of ?G,whilst the deduced expression gives a value of x which increases as Rdiminishes.Solids.-Though most of the studies of the action of ionising radiations onsolids are primarily physical, some of chemical interest have appeared. Manyof these concern investigations of the irradiation of polymers. The effectsproduced by the irradiation of a variety of polymers with pile radiation andelectrons are very dependent on the presence or absence of oxygen and onthe dose rate.357 The most stable types of polymer are those which canform close-packed crystallites, e.g., linear polymers without side-chains,and two quite clear-cut classes exist, viz., those which are predominantlydegraded and those which are predominantly cro~s-linked.~~~ Polyethyleneis in the latter class.359 y- or Neutron-irradiation causes C-H bond fracture,with the liberation of hydrogen gas and the production of cross-linking.Fracture of C-C bonds does not occur.Polystyrene, poly(ethy1ene tere-phthalate), nylon, and unvulcanised rubber also fall into this butpolytetrafluoroethylene 361 and polymethyl methacrylate 362 are degraded,C-C bonds being preferentially fractured. All these results are in keepingwith observations on depolymerisations by non-radiation methods. An352 F. S. Dainton and N. Miller, Proc. Int. Congress of Pure and Applied Chemistry,1947, 1, 77.354 E.Collinson and F. S. Dainton, Discuss. Faraday SOC., 1952, 12, 251.355 W. H. Seitzer, R. H. Goeckerman, and A. V. Tobolsky, J . Anaer. Chew. SOC., 1053,75, 755.S56 I. A. Berstein, E. C. Farmer, TV. G. Rothschild, and F. F. Spalding, J . Chem.PAYS., 1953, 21, 1303. 357 K. Little. Nature, 1952, 170, 1075.358 E. J. Lawton, A. M. Bueche, and J. S. Balwit, Nature, 1953, 172, ?6.359 A. Charlesby, Proc. Roy. SOC., 1952, A., 215, 187.360 Idem, Nature, 1953, 171, 167.381 Idem, Atomic En. Research Establishment Report, 1952, A.E.R.E.-M/R-978.363 A . Charlesby and M. Ross, Natzire, 1953, 171, 1153.353 A. Chapiro, Conapt. rend., 1953, 237, 247COLLINSON, DAINTON, AND IVIN: HOMOGENEOUS SYSTEMS. GTinvestigation of the effect of pile irradiation on several polymers, by meansof subsequent viscosity measurements of the polymer solutions, supports theabove results,363 and it is suggested that pre-determined amounts of cross-linking might be produced by introducing suitable groups into the polymer.There was some indication of the existence of free immobilised radicals inthe solid polymers after irradiation.During the irradiation of nitrate crystals in the atomic pile, oxygengas and nitrite ions were formed in equivalent amounts.The effects weremainly produced by electronic ionisation and excitation rather than by elasticcollisions with particles.364 The primary products of the decomposition ofpotassium perchlorate by 50 kvp X-rays are potassium chlorate, potassiumchloride, and oxygen.365 The reaction is of first order and has a yield,G, of 5.3.Water and Aqueous Solutions.-" In spite of the large amount of carefulexperimental work which has gone into the subject, we are still a good wayfrom providing firm experimental groanding for any theory of the radiationchemistry of water," states a leading worker in this field.366 However, thisdoes not prevent new theories from being advanced. Samuel and Magee,3G7in developing a theory in which hydrogen atoms and hydroxyl radicals areconsidered to be the only active radicals produced, have concluded, contraryto earlier theories,36s that the radicals are most likely to be formed in pairs,approximately at the sites of ionisations.Calculations based on the diffusionand recombination of radicals lead to the view that with the exception of theforward ( F ) and the radical (I?) reaction,* effects of geometrical distributionof reactive species can be ignored for all cases of the reaction of a solute inaqueous solution.In the past it has been assumed thatthe yields of hydrogen and hydroxyl radicals, denoted by GR, were equal,and that the " molecular " yields of hydrogen and hydrogen peroxide,denoted by Gp, were also equal.Direct evidence has shown that thisassumption is incorrect and that the yields of hydrogen peroxide and hydro-gen radicals are respectively greater than those of hydrogen molecules andhydroxyl radicals.369 This result necessitates the introducticn of threeequations to represent the primary effect of ioiiising radiations on water.Dainton and Sutton write these as 2H,O -++ 20H + 2H ; 2H20 --+ H +20H ; and 2H20 -+ H202 + 2H. Allen 366 allows for the new effect byadding the last of these processes [called by him reaction ( E ) ] to his earlierequations (3') and (R), and summarises other indirect evidence for and againstreaction ( E ) .On the assumption of the existence of this reaction he hassurveyed and re-evaluated the existing experimental data on rzdical and(i) The molecular and radical yield.363 L. A. Wall and M. Magat, J . Chiiiz. phys., 1953, 50, 305.364 G. Hening, R. Lees, and M. Matheson, J . Chem Phys., 1953, 21, 664.365 H. G. Heal, Canad. J . Chem., 1953, 31, 91.366 A. 0. Allen, U.S. Atomic En. Commiss.Report, 1953, BNL-1498.367 A. H. Samueland J. L. Magee, J . Chem. Phys., 1953, 21, 1080.36* D. E. Lea, " Actions of Radiations on Living Cells," 1947, Cambridge University36* F. S. Dainton and H. C. Sutton, Trans. Faraday SOL, 1953, 49, 1011. * These reactions arePress; J. Read, Brit. J . Radiol., 1951, 24, 345.H,O ---+ I3 + OH ( R )H,O ---+ +H, + +H,O, (I;) (See Ann. Reports, 1952, 49, 7 2 . 68 GENERAL AND PHYSICAL CHEMISTRY.molecular yields.one in his paper.y-rays.]Radiationy ..................... x ..................... x ..................... x ..................... x ..................... x .....................Tritium 6 .........u (Po) ...............The following table is an extract from a more complete[The yields are based on the value G(Fe2+),,,.= 15-5 forInitialelectronenergyW ) GH2 GHpOz GOHSolvent : 0~8N-sulphuric acid500 0.48 0.87 2.8627 0.5 0.97 2.5823 0.55 1.01 2.5620 0-6 1.05 2.4320 0.6 1.08 2.3811 0.7 1.17 2-235.7 0.9 1.59 1.35- 1-57 1.87 0.2GH3-643.523-503.333.343.172.730.84.604.624.604.534-544.574-533.94Solvent : watery ..................... 500 0.6 1.05 1.7 2-6 3.8A' ..................... 30 0-56 1.43 0.9 2.64 3-76o! (Rn) ............... - 1.8 1.9 0.1 0-3 3.9The molecular yields are seen to increase, and the radical yields to de-crease, as the ion-density increases. It is found, however, that the imtnn,-taneozls yields (like the overall yields, GHZO) remain constant down to thelowest energies used, and it is suggested that the changes in the observedradical and molecular yields are due to the higher proportion of track-ending concomitant with electrons of lower initial energy.The constancyof GR,O suggests that the radicals are initially separated rather than sideby side, a conclusion which is at variance with the theory mentioned earlier.367The difference in behaviour of water and aqueous sulphuric acid is interest-ing. Allen suggests that there may be complex-formation between hydroxylradicals and sulphuric acid or its ions, and that there is a more ready neutral-isation of positive and negative ions in the acid. In water a greater mole-cular yield may arise from a process of the type 2H,O+ __+t H,02 + 2H+.It should be remembered that complete and consistent as the data lookthey have all been obtained from a limited number of systems. The highvalue of G B (12.6 & 1.8) obtained from the radiolysjs of hydrogen peroxide,linked with the fact that no hydrogen production was detected in theseexperiments,370 evokes the suspicion that the measured yields, and alsothe ratios between Gn, Gp, and GE may be very dependent on the soluteused as well as on the type of radiation.Dewhurst 372 has studied the effect ofmany variables on the kinetics of the 50 kvp X - and 6oCo-y-ray oxidations offerrous sulphate solutions; the results indicate that there is no difference inthe effects of the two types of radiation.The mechanism proposed by Rigg,Stein, and Weiss 371 is not adequate to explain some of the results, especiallya t low acid concentrations, and no other homogeneous stationary-statetreatment could be found to explain all the facts.It is suggested that thesystem may involve non-stationary-state kinetics. Dainton and Sutton 369also found indications of the reaction's occurring in localised zones alongelectron tracks. Both Dewhurst and Dainton and Sutton found the exist-(ii) The ferrous-ferric system.370 F. s. Dainton and J. Rowbottom, Tyans. Faraday SOC., 1953, 49, 1160.371 T. Rigg, G. Stein, and J. Weiss, Proc. Roy. SOC., 1952, A , 211, 375.372 H. A. Dewhurst, Traits. Faraday SOC., 1053, 49, 1174COLLINSON, DAINTON, AND IVIN HOMOGENEOUS SYSTEMS. 69ence of a post-irradiation oxidation of ferrous ions in dilute aerated solutions.This was shown to be due to the slow reaction between hydrogen peroxideand ferrous ions.The latter authors also found a post-irradiation effect inde-aerated solutions a t concentrations lower than those used by Dewhurst.This was attributed to the molecular production of hydrogen peroxide.Amphlett 373 has confirmed that the reduction of aerated ferric-ion solutionsby y-rays occurs with high yield in solutions of high pH. At pH 2.46,G = -16. A steady state, in which the ratio of Fe3+ : Fe2+ depends on thetotal iron concentration, is soon attained. The steady state does not havethe same value if reached by the oxidation of ferrous ions, indicating thatthe system is not thermodynamically reversible with respect to hydrogenatoms and hydroxyl radicals.I t is suggested that at high pH there is com-petition between the processes FeOH2+,,. + Haq. -+ and H + 0, --+HO,. Dewhurst 372 was unable to detect the formation of stationary statesof this type. The temperature coefficient for the oxidation by y-rays hasbeen r e m e a s ~ r e d . ~ ~ ~The oxidation of ferrous ions in aerated 0.8~-sulphuric acid by the x-raysof polonium (dissolved in the solution) gives a yield, G, = 6, which does notvary with the intensity of the irradiati0n.37~ Employing a method of cal-culation which depends on the additivity of the effects of a-, (3-, and y-radiation on the ferrous-0-8~-sulphuric acid system, Lefort 376 deducesthat for aerated solutions G, = 6.2, and for de-aerated solutions G, = 3.7.The reduction of aerated ferric tris-o-phenanthroline by y-irradiation iscomplicated by an after-effect lasting for several The effect isless marked in more acid solutions, less important at low dose rates, andabsent in de-aerated solutions.Yields in aerated solution are G = 12 atpH = 0 and G = 14 at pH = 4 (the after-effect being allowed to go tocompletion); in de-aerated solution G = 3.5 at pH = 0 and G = 4.5 atpH = 4.A large number of inorganic and organicsystems have been examined, and in this section only those aspects of thegreatest general interest will be covered.An apparent dose-rate effect has been found in the reduction of cericions by polonium a - r a y ~ , ~ ~ ~ the yield decreasing with increasing dose rate.A dependence on the cube root of the dose rate for the yield of the destruc-tion of tartrazine by electrons 378 has been conceived as due to greater com-petition by the reaction H + OH --+- H,O at higher dose rate^.^'^ Thisdoes not seem to be a likely explanation for the above a-ray results.A dose-rate effect has also been found in the formation of hydrogen peroxide by thel-Mev-proton irradiation of water,380 the yield decreasing as the dose rateincreases. The results suggest that there may be a maximum efficiency ofhydrogen peroxide production at a particular dose rate for each type ofradiation.For a-irradiations G, = 0.95.376(iii) Other aqueous systems.373 C. B. Amphlett, Nature, 1953, 171, 690.374 T. J. Hardwick, Canad. J . Chem., 1953, 31, 881.3 7 5 M.Haissinsky and (MIle.) C. Anta, Compt. rend., 1953, 236, 1161.376 M. Lefort, ibid., 237, 159.377 M. J. Pucheault and M. Lefort, J . Chim. phys., 1953, 50, 196.378 A. Brasch, W. Huber, and A. Waly, Arch. Biochern. Biophys., 1952, 39, 245.379 W. Dittride, 2. Naturforsch., 1953, 68, 10.350 R. J. Shalek and T. W. Bonner, Nature, 1953, 172, 25970 GENERAL AND PHYSICAL CHEMISTRY.The actions of various ionising radiations on solutions of phosphites pro-vide further evidence that more complex entities than hydrogen atoms andhydroxyl radicals must be formed from the ~olvent.~8lThe reduction of ceric ions by y-radiation appears to take place via theaction of hydrogen peroxide and not via OH or HO, radicals as was earliersuggested.382 This contrasts with the suggestion that the Ce4+-H,O,reaction takes place via HO, radi~a1s.l~~The hydroperoxide radical is considered to be the effective entity in thedegradation of poly(methacry1ic acid), and this has been suggested as amethod of testing the biological protective action of chemical compounds.383Of bearing on this work is that of Wall and Magat 363 who studied degradationof polymers in non-aqueous solutions.In carbon tetrachloride the activedegrading agent clearly cannot be HO,, but oxygen is still necessary fordegradation. They suggest that polymer chains are here broken by directaction of the radiation and that the effect of oxygen is to prevent recom-bination of the broken chains. A protecting agent is then envisaged as achain-transfer agent which stabilises the radicals before oxygen can inter-vene.In support of this, the action of cystine on the polymerisation ofacrylonitrile indicates that it behaves as a transfer agent.384 It has alsobeen suggested that the effective entity in the oxidation of indigo carmineby y-rays is the HO,E. C.F. S. D.K. J. I.4. REACTIONS AT SOLID INTERFACES.This Report has been restricted by limitations of space to decompositionsproceeding at solid interfaces; no Report 1 on this topic has previouslyappeared although there are recent reviews on solid-solid interface reactionsand on reactions of gases at the surfaces of solids3 The latest surveys onsolid decompositions were published in 1938 ; 43 5 consequently althoughemphasis is given to current developments, the progress over the past 15years is summarized.Nucleus Formation and Growth.-The original concept that the overallrate of decomposition can be expressed in terms of the rates of nucleusformation and growth is still retained.In general terms, the nucleus maybe regarded as a localized array of product in the reactant matrix; reactionnormally proceeds preferentially at the interface because, on account ofreactant-product co-operation, the activation energy is here a minimum.Two types of nuclei may be distinguished : the growth nucleus which has381 M. Cottin and M. Haissinsky, J. Chirn. phys., 1953, 50, 195.382 T. J. Sworski, J. Chem. Phys., 1953, 21, 375.383 P. Alexander, Brit. J . Radiol., 1953, 26, 413.334 (Mme.) A.Prdvot-Bernas, J. Chim. phys., 1953, 50, 445.385 L. Mongini and E. L. Zinimer, ibid., p. 491.Cf., however, H. W. Melville, Ann. Reports, 1938, 35, 81.,,J. A. Hedvall, " Einfuhrung in die Festkorperchemie, 1952 ; InternationalJ . S. Anderson, Tilden Lecture, 1953.W. E. Garner, Sci. Progress, 1935, 33, No. 130.Faraday Society Discuss., 1938, 34, especially pp. 821-1010.Symposium on the Reactivity of Solids, Gothenburg, 1952TOMPKINS AND YOUNG REACTIONS AT SOLID INTERFACES. 71a predominant tendency to grow, and the germ nucleus which has dimen-sions less than the critical requirement and tends to decrease in size andultimately disappear.treatment, who applied the formalism of the Volmer-Becker theory tonucleation in solids; in this context, the nucleation rate reflects, in part, themobility of atoms (ions) in the crystalline lattice as a function of the activ-ation energy for diffusion (or ion conductance) and contains an exponentialterm related to the entropy decrease attending nucleus formation.Turnbulland Fisher have recently introduced derivations using the method of theabsolute reaction theory and further developments using this approach aregiven in two later papers.9~ 10 For simplicity, nuclei are assumed to bespherical, although, both from experimental observations and theoreticalconsiderations, disc- or needle-shaped clusters with definite preferred orient-ations with respect to the parent lattice should be considered.ll Similarly,any rigorous theory should consider the strain energy arising from latticedeformations.Such energy forms part of the free energy of formation ofthe germ nucleus since specific volume changes, occasioned by the produc-tion of ions of different size and number, invariably occur ; and these changes,which become greater with increasing size of the nucleus, can only be accom-modated by strains in both the reactant and product. However, althoughthe strain energy is a minimum for disc-shaped nuclei, the anisotropy l3 ofthe interfacial energy of reactant and product often controls the shape ofthe nucleus, since there will be a definite crystallographic relation such thatplanes having greatest similarity in atomic packing will tend to be parallel.Theoretically the problem may be treated by considering the interface as amisfitting monolayer.l4 In addition, from X-ray evidence, it now seemsclear that there are present nuclei of varying composition and stability, allof which have some tendency to grow into stable growth n~c1ei.l~It is now, how-ever, accepted that real crystals contain non-equilibrated imperfections(e.g. , Frank-Read sources 16) that generate dislocations thereby permittingplastic flow under small stress.Growth of nuclei will consequently bepreferred in those crystal elements having dislocations in their vicinity,since large stress cannot be supported there ; and, moreover, because stressesmay be relieved more readily at interfaces, nucleation will be easier at grainboundaries and free surfaces, as has been experimentally demonstrated byHedges and Mitchell l7 for the photodissociation of silver bromide.In general, diffusion rates in solids are small and the time to attain asteady-state production of nuclei becomes comparable with that required to13.Becker, Ann. Physik, 1938, 32, 128.R. Becker and W. Doring, ibid., 1935, 24 ( 5 ) , 719; M. Volmer, “ Kinetik derPhasenbildung,” Steinkopf, Dresden, 1939.D. Turnbull and J. C. Fisher, J . Chem. Phys., 1949, 17, 71.D. Turnbull, zbid., 1950, 18, 198.lo I d e m , ibid., 1952, 20, 411.l1 See, for example, A. Guinier, PI^. Phys. Soc., 1945, 5’7, 310; C. S. Barrett andA. H. Geisler, J . Appl. Phys., 1940, 11, 733.l2 D. Turnbull and B. Vonnegut, I n d . Bng. Clienz., 1952, 44, 1292.l3 Cf. ref. 4 and J.N. Hobstetter, Metals Tech., 1948, 15, t.p. 2447.l4 F. R. N. Nabarro, Pmc. Phys. Scc., 1940, 52, 90; Proc. Roy. Soc., 1941, -4, 175, 519.l 5 Ci. Borelius’s theory; G. Borclius, A m . Physik, 1938, 33, 517.l6 F. C. Frank and W. T. Read, Phys. Review, 1950, 79, 722.l 7 J. M. Hedges and J. W. Mitchell, Phil. Mag., 1953, 44, 357.Theoretical developments have followed Becker’sAs yet, the assumption has been that the solid is ideal72 GENERAL AND PHYSICAL CHEMISTRY.complete the reaction; consequently the nucleation rate is a function oftime. In such circumstances, Frenkel’s method,18 in which the size ofthe germ nucleus is treated as a continuous variable, has greater validity;this treatment has been recently rigorously developed by Turnb~1l.l~ Anattempt has also been made to take account of the influence of the growingnucleus on the probability of nucleation in its proximity.20 The ingestionof preferred nucleation sites by the growing nucleus and the elimination ofsmall nuclei by overlap with large ones has been considered by Avrami,21by Turnbull,22 who considers the effect of the presence of initial transients,and by others23Most of the theoretical treatments have been concerned with homo-geneous, structure-insensitive nucleation in the interior of the reactant ;the interest for interface reactions is, however, centred on the structure-sensitive nucleation at the interface.It is, therefore, important to notethat analogous expressions can be derived for this latter case.24 Neverthe-less, it is normally implicit in all derivations that the properties of germ andsmall growth nuclei containing only 10-30 units can be described in termsof macroscopic thermodynamic properties.Some doubt, however, hasbeen expressed about the validity of this extrapolation and modified expres-sions have beenFrom the viewpoint of thermal decompositions the tendency recentlyhas been to favour this concept of discrete nuclei in interpreting the resultsof kinetic studies, and the theory of diffuse nuclei has not been developed.The most general mathematical treatment applied directly to decom-positions has been given by Mampel; z8 it includes the combined effects ofrandom formation and growth together with corrections for the overlappingof nuclei and the ingestion of nucleation sites.His final equation is formallythe same as that of Avrami and of E r ~ f e e v , ~ ~ viz., cc = 1 - exp(- W ) ,where a is fractional decomposition, k a velocity constant, and n a constantwhich includes the power dependence of formation and growth on time.Mampel has also investigated the effect of particle size on the form of thedecomposition curve and derived various equations depending on therelative magnitude of the velocity constant of growth and the particleradius.Although the original linear branching chain mechanism 31 has lostMacdonald’s two-dimensional analogue 33 applied to silver oxalat eJ. Frenltel, “ Kinetic Theory of Liquids,” Clarendon Press, 1946; J. Zeldovich,Acta Physzcochinz. U.S.S.R., 1943, 18, 1.l9 D.Turnbull, Metals Tech., 1948, t.p. 2265.2o W. G. Burgers, Nature, 1946, 157, 76.21 M. Avrami, J . Chem. Phys., 1939, 7, 1103; 1940, 8, 212; 1941, 9, 177.22 D. Turnbull, Amer. Inst. AJiuz. Met. Eng., t.p. 2365, Metals Tech., 1948.23 A. Kantrowitz, J . Chem. Phys., 1951, 19, 1097; R. F. Probstein, ibid., p. 689.24 D. Turnbull, in “ Phase Transformations in Solids,” 1951, p. 180.25 13. Reiss, J . Chem. Phys., 1952, 20, 1216; R. C. Tolman, ibid., 1949, 17, 333.26 J. G. Kirkwood and F. P. Buff, ibid., 1949, 17, 338; 1950, 18, 991.2 7 F. P. Buff, zbzd., 1961, 19, 1591.K. L. Mampel, 2. physikal. Chenz., A , 1940, 187, 43.29 B. V. Erofeev, Doklady Akad. Nauk, S.S.S.R., 1946, 52, 511.30 K. L. Mampel, 2. physikal. Chem., A , 1940, 187, 235.n1 W.E. Garner and H. R. Hailes, Proc. Roy. Soc., 1933, A , 139, 576.‘? J. Y . Macdonald, Trans. Faraday Soc., 1938, 34, 977.33 Idem, J . , 1936, 832, 839TOMPKINS AND YOUNG: REACTIONS AT SOLID INTERFACES. 73has been generalized 3* in crystallographic terms to include interference ofchains, and the Prout-Tompkins equation in the form log {$/(P, -p)> =kt + constant, where fif is the final pressure corresponding to completedecomposition, has been applied to the kinetics of decomposition of variouscompounds, e.g., permanganates, oxalates, fulminates, etc. The mechanismhas recently been reformulated in terms of dislocation theory.35Decompositions of Specific Compounds.-Hydrates.-Recent investigationshave been confined almost entirely to the alums.Cooper and Garner,36 ina re-examination of the dehydration nuclei on single crystals of chrome alumi n uac~to now distinguish two types: (I) pink, formed above 20" c withE(growth) = 31 kcal./mole, and (11) white, formed below 20°, with E(growth)of 28-5 kcal./mole and converted into (I) on coalescence with (I) nuclei. Theentropy, or B-factor, of (I) is 10l2 times greater than that calculated theoretic-ally from the Polanyi-Wigner equation. Anous, Bradley, and C~lvin,~'using a specially designed microbalance, however, find a normal B-factorwith E(growth) = 23 kcal./mole between 15" and 35", and E(growth) = 30kcal./mole and a B-factor 1O1O greater than the theoretical value between-1-7" and -12". No completely satisfactory explanation has beenadvanced for the abnormally high B-factor; in part, it is attributed to thedecrease in thickness of the amorphous-product transition-layer withincreasing temperature 36 or, alternatively, to a rapid reaction through thecrystal mosaic blocks with delays between blocks due to the requirement offresh n~cleation.~' The initial slow-growth rate of small nuclei on chromealum, previously attributed to the variation of interfacial tension withcurvature of the nucleus,38 has received two alternative explanations ;Bradley 39 shows theoretically that the presence of the dehydrated phaseincreases the activation energy for the escape of water molecules from theinterface as the curvature of the interface increases.Ma~donald,~~ how-ever, from more general considerations of the difference of lattice energiesof reactants and products and the surface migration of vacancies, concludesthat the increase of activation energy for water molecules to pass acrossthe interface with decreasing size of the nucleus is the determining factor.A new phenomenon with chrome alum is reported by Garner and Jennings ; 41the original spherical nuclei formed in vacua are accompanied by a largenumber of smaller nuclei which become visible only when the crystal isexposed to a critical water-vapour pressure; the effect is not found withpotash alum.The authors account for the occurrence of these satellitenuclei in terms of the irreversible production of a zeolitic zone; furtherevidence of the irreversibility of the dehydration process is given in a studyof the rehydration of dehydrated potash alum by Tompkins and Bielanski,&dwho find that the rate of uptake of water, after an initial monolayer adsorp-tion, is diffusion-controlled.The first attempt to formulate a detailed mechanism of nucleus formation34 E.G. Prout and F. C. Tompkins, Trans. Faraduy Soc., 1944, 40, 488.35 A. Finch, P. W. M. Jacobs, and F. C. Tompkins, J . , 1954, in the press.36 J . A. Cooper and W. E. Garner, Proc. Roy. Soc., 1940, A , 174, 487.3 7 M. M. T. Anous, R. S. Bradley, and J. Colvin, J., 1951, 3348.38 J. A. Cooper and ?V. E. Garner, Trans. Faraday SOC., 1936, 32, 1730.39 R. S. Bradley, ibid., 1951, 47, 630.42 A. Bielanski and F. C. Tompkins, Trans. Faraday Soc., 1950, 46, 1072.40 J .Y . Macdonald, e'bid., p. 860.W. E. Garner and Jennings, personal communication74 GENERAL AND PHYSICAL CHEMISTRY.has been made by Acock, Garner, Milsted, and Willa~oys.~~ The initialstage is thought to be the aggregation of lattice vacancies at the crystalsurface; these are produced by surface evaporation of water molecules andby migration of defects from the interior to the surface. Nucleus formationceases when the rate of surface evaporation is too small to maintain the rateof formation of the small aggregates. In addition, the paper gives a largenumber of experimental data on the shape and appearance of nuclei andon the magnitude of the B-factors and ,!?(growth) for a series of mixedalums.Additional data, mainly concerning equilibrium water-vapour pressuresand heats of dissociation, are given by Hepburn and Phillips,44, 45 whoattribute the primary dissociation to the reactionM+(6Hz0)R13+(H,0),(SO~)~ M+M3+(H,0),(S0,), + 6H,Oi.e., to loss of water molecules cc-ordinated to the univalent cation.Theyconclude that the stability of alums to dehydration decreases with decreasingsize of the M+ ion and increasing size of the M3+ ion, and suggest that ondehydration, a residual skeleton lattice film held to the reactant latticeby valency forces is first formed; only the outer layers are metastable andundergo rearrangement. This theory differs from Garner's concept of aninitially-formed zeolitic structure which later collapses and recrystallizes.The effect of an ambient water-vapour pressure on the rate of decom-position of finely divided samples of copper sulphate pentahydrate has beeninvestigated by Frost and Campbell,46 following the suggestion by Frost,Moon, and Tompkins 47 that similar behaviour to that found with manganeseoxalate dihydrate should be observed.Discontinuities in the rate curves forthe dehydration of nickel sulphate heptahydrate and in the rehydration ofthe products have been recorded4* and ascribed to the formation of inter-mediate hydrates. Roginskij has reported on some electron-microscopicobservations made during the dehydration of hydrates.49Oxides and Carbonates.-The autocatalytic nature of the decompositionof silver oxide in an oxygen atmosphere, first investigated by Lewis,50 hasbeen confirmed by Hood and Murphy,51 but Pavlyuchenko and Gurevich 52obtained complex fi-t plots and a very low activation energy of doubtfulvalidity.However, many of the previous divergent results have now beenresolved by Garner 2nd Reeves 53 who used an oxide prepared similarly toLewis's but annealed in oxygen at 200-340" for 8-10 days. They obtainedsimple kinetics for its decomposition i p 2 vacuo that were consistent with thethree-dimensional growth of a constant number of nuclei ; with un-anneaIedoxide the normal interface reaction is obtained. If the decomposition takesplace in presence of oxygen the growth of small silver nuclei is inhibited.43 G. P. Acock, W. E. Garner, J. Milsted, and H. J. Wiliavoys, PYOC. Roy. SOC., 194.7,4 5 R.F. Phillips, J., 1952, 2578.46 G. €3. Frost and R. A. Campbell, Canad. J . Clam., 1053, 31, 107.4 7 G. €3. Frost, K. A. Moon, and E. H. Tompkins, ibz'd., 1951, 29, 601.48 B. Ghosh, J. Indian Chem. Soc., 1941, 18, 472.49 S . 2. Roginskij et al., Doklady Akad. Nauk S.S.S.R., 1940, 68, 879.50 G. N. Lewis, 2. physikal. Chem., A , 1906, 52, 310.51 G. C. Hood and G. W. Murphy, J . Chew. Educ., 1049, 26, 169.52 M. M. Pavlyuchenko and E. Gurevich, Zhur. Obshchei Khim., lMP, 21, 467.83 W. E. Garner and L. W. Reeves, Trans. Faraday SOC., 195% 88, in the press,189, 309. 44 J. R. I. Hepburn and R. F. Phillips, J., 1952, 2569TOMPKINS AND YOUNG : REACTIONS AT SOLID INTERFACES. 75The semi-conductivity of the oxide was also measured but there seemed nolink between this property and the mechanism of decomposition.Dolomite, because of its industrial importance, has been the most exten-sively studied of the carbonate^.^^ The products depend on whether thedecomposition takes place in vacuo or in an atmosphere of carbon dioxide :in vacuo : MgCa(CO,), -P CaO + MgO + 2C0, .. * ( 1 )in carbon dioxide : CaCO, + MgO + CO, . . - (2)The initial product in (1) is said to be (Ca,Mg)O, having a pseudo-dolomitestructure which later breaks down into separate crystallites of calcium oxideand magnesium oxide,55 the size of which increases regularly with increasingtemperature of decomposition.60 There is little agreement as to the mechan-ism of formation of the " half-burned " dolomite [reaction ( Z ) ] ; the followinghave been suggested : (i) an initial dissociation 56 into the constituentcarbonates, involving cation-site interchange, followed by independentdissociation of these; (ii) a direct decomposition 57 into calcium oxide andmagnesium oxide and re-formation of calcium carbonate with the escapingcarbon dioxide; (iii) the initial production 58 of some magnesium oxide anda solid solution of calcium carbonate and " magnesium carbonate deficientin MgO " ; and (iv) partial dissociation 59 into calcium oxide and magnesiumoxide followed by the reaction, CaO + CaMg(CO,), --+ 2CaC0, + MgO,since it is found that admixture with dry calcium oxide reduces the tem-perature of decomposition in an atmosphere of carbon dioxide.X-Rayanalysis 6o shows that there is a minimum in the particle size of the productsat 685", the larger calcite crystallites being aligned parallel to the originaldolomite lattice whereas the magnesium oxide is irregularly oriented.Atthis temperature the Mg2r ions are mobile in a highly defective lattice anddiffuse across the plane of the interface, whereas the Ca2+ ions are practicallyimmobile. The function of added dry calcium oxide is, therefore, to providea larger interface (by reaction with carbon dioxide) and thus to facilitatedecomposition. No satisfactory explanation has been given of the retentionof half the content of carbon dioxide and the lowering of the activationenergy to half the normal value when the decomposition is effected in ahydrogen atmosphere.61With the simple carbonates, it is confirmed that calcite and magnesite 62decompose in vacua by an interface mechanism, although there are departuresfrom the rate equation expected for the penetration of a completely nucleatedsurface. These are attributed to the slow rate of nucleation, self-cooling,and impedance to the escape of carbon dioxide.Cremer,63 however, con-54 TV. 24011, Angeu. Clzenz., 1950, 62, 567; R. A. W. Haul and J . Marlrus, J . A$pl.Chein., 1952, 2, 298.5 5 13. T. S. Britton, S. J. Gregg, and G. W. Winsor. Trans. Faraday SOC., 1952, 48, 70.5 6 C. W. Potapenko, Zhuv. Priklad. Khim., 1932, 5, 693; M. Faqueret, Bull. SOC.frang. Miiz., 1940, 63, 88; 1'. Schwob, @omn$t. r e d . , 1947, 224, 47.5 7 H. Flood, K g l . Norske Vidensk.Selsk. Fsrh., 1930, 22, 188.5 8 P. V. Gel'd and 0. A. Esin, Zhztr. Priklad. Khinz., 1949, 22, 240; 0. A. Esin,P. V. Gel'd, and S. I. Popel, ibid., p. 354.59 J. A. Hedvall, 2. anorg. Chew., 1953, 272, 22.Go R. A. W. Haul and F. R. L. Schoning, Z. anorg. Chem., 1952, 269, 120; R. A. W.Haul and H. Wilsdorf, Actn Cryst., 1952, 5 , 250; R. Meldau and R. H. S. Robertson,Nature, 1953, 172, 998.6z H. T. S. Britton, S. J. Gregg, and G. W. Winsor, Trans. Faraday SOC., 1952, 48, 63.63 E. Cremer, Z. apzorg. Chem., 1949, 258, 123.61 F. Bischoff, Z. anorg. Chew., 1950, 262, 28876 GENERAL AND PHYSICAL CHEMISTRY.cludes that for the first 10-50% decomposition the rate for magnesitevaries as tf and suggests a rate-controlling diffusion process.As is fairlygeneral, values of the activation energies of these dissociations are aboutthe same as the heats of reaction. Zinc carbonate 64 is an exception to thisrule, the heat of activation being much the larger owing to lack of reversibilityof the dissociation. The decomposition of sodium and potassium hydrogencarbonates obeys complex kinetics-decomposition of the former 65 is at firstunimolecular, then of zero order, but finally a fractional order less thanunity is obtained. Formation and decomposition of intermediates arepostulated 66 in the decomposition of potassium hydrogen carbonate.Formates and 0xaZates.-Both nickel and cobalt formate decomposeaccording to the scheme :M(H*COO), M + H, + 2C0, . * (i)M + H,O + CO + CO, . . (ii)Zelinskaya and D ~ b y t s h i n , ~ ~ however, reported that (i) predominates forthe nickel salt and gives a simple dependence of the pressure increase on thethird power of time.Erofeev,68 using cobalt formate, also consideredreaction (i) only and found Mampel’s equation valid up to 50% decom-position. Bircumshaw and Edwards 69 produce analytical data for theexistence of both reactions with nickel formate and, despite their findingthat grinding did not accelerate the rate, showed that the Prout-Tompkinsequation was applicable. It seems more probable that these decompositionsare similar to that of silver oxalate but that the kinetics are complicated notonly by the retardation effect of one product (water) and an accelerationby another (the but also by the different contributions of (i) and (ii)to the pressure increase as the reaction proceeds.70Further attention has been given to silver oxalate since it decomposessmoothly and stoicheiometrically to metal and carbon dioxide.Earlierlack of reproducibility has been rectified 71 and the kinetics are shown todepend on the age of the sample as well as on the conditions of prepar-ation.71’ 72 A well-aged stoicheiometrically-prepared sample gave resultsconsistent with three-dimensional growth subsequent to nucleus formationat a limited number of sites according to a first-order decay, whereas asimilar, but freshly prepared, specimen gave results corresponding to thebranching of two-dimensional plates,723 73 as might be expected from thelayer-lattice structure deduced by Griffith 74 from X-ray measurements onthe original and the decomposed salt.These different theories have beenbrought together by postulating nucleation and branching at di~locations~7~64 J. Zawadzki and W. Szamborska, Bull. Acad. polonaise, A , 1948, 27. For a reviewin English of Zawadzki’s work on carbonates see “ Festskrift tillagnad J . A. Hedvall,”Goteborg, 1948.G 5 R. Tsuchiga, J . Chern. SOC. Japan, 1953, 74, 16. 6 6 Idem, ibid., p. 97.6 7 N. D. Zelinskaya and D. B. Dobytshin, quoted by S. 2. Roginskij, Trans.6 8 B. V. Erofeev, Zhur. Fiz. Khim., 1940, 14, 1217; 0. M. Todes, ibid., p. 1224.69 L. L. Bircumshaw and J. Edwards, J., 1950, 1800.70 A. A. Balandin, E. S. Gsegorian, and Z. S. Janischeva, Zhur.Obshchei Khim.,71 F. C . Tompkins, Trans. Faradq SOC., 1948, 44, 206.72 A. Finch, P. W. M. Jacobs, and F. C. Tompkins, J . , 1954, in the press.73 J. Y . Macdonald, J . , 1936, 832, 839.74 R. L. Grifith, J . Chem. Phys., 1946, 14, 408.Faruday SOC., 1938, 34, 959.1940, 10, 1031TOMPKINS AND YOUNG : REACTIONS AT SOLID INTERFACES. 77i e . , that the determining factors are the crystallographic characteristics of thesalt. Measurements of ionic conductance 729 75 confirm that the decom-position is an interface reaction ; the lack of photoconductance under irradi-ation and the similarity of the kinetics of prolonged photolysis 72 to thosefound with azides are explained in a theory involving exciton production.Other oxalates, in particular those of lead and mercuric mercury, decom-pose to the metal, its oxide, carbon monoxide, and carbon dioxide.TheProut-Tompkins equation 34 holds for the decomposition of the lead salt.76The kinetics for mercuric oxalate 77 are similar to those found with the silversalt although complications arise from the production of mercurous oxalateas an intermediary. An initial accelerating rate due to an expanding surfacereaction is followed by a constant rate of penetration of the interface, butafter ultra-violet irradiation a rapid first-order decay proceeds initiallybefore the constant rate is attained. Both 72 oxalates react similarly tothe silver salt under prolonged photolysis. The study of the complexdecomposition of hydrated thorium oxalate has yielded little of kineticvalue.78Permanganates.-The products of decomposition are oxides of manganeseand the cation (together with compounds of these) and oxygen. Exceptwhen the kinetics are determined predominantly by crystallographic ratherthan chemical properties, simple p-t plots are not obtained. With thepotassium salt,79 a branching mechanism dependent on lattice strains, setup by the difference of lattice parameters of products and reactant, is foundto be applicable, but the theory is not valid for the silver salt unless thebranching coefficient is assumed to vary with the fractional decomposition.Erofeev and Smirnova 81, 82 have applied the Mampel equation to the break-down of potassium permanganate but give different values for the exponentin two separate investigations.The decomposition of ammonium per-manganate 83 is most complex; not only is the ammonium ion oxidisedduring the decomposition but one of the products (ammonium nitrate) isthermally unstable and its breakdown is catalysed by one of the otherproducts, manganese dioxide.A new technique of examining the physical nature of the product layerformed on the surface of the barium salt has been devised by Roginskijet al.; 84 this layer, which is amorphous with a high surface area (6 m.2/g.from gas-adsorption measurements), is found to be an exact replica of thesurface of the original crystal. The particles of product penetrate into thereactant but only attain a linear dimension of low5 mm.; these findings arenot inconsistent with the Prout-Tompkins theory.The effect of the nature of the cation on the ease of decomposition of aseries of permanganates has been studied.By arbitrarily defining the75 W. E. Garner and L. W. Reeves, private communication.7 6 L. L. Bircumshaw and I. Harris, J., 1939, 1637; 1948, 1898.7 7 E. G. Prout and F. C. Tompkins, Trans. Faraday Soc., 1947, 43, 148.7 8 R. Beckett and M. E. Winfield, Austral. J . Sci. Res., 1951, 4, 644.7Q E. G. Prout and F. C. Tompkins, Trans. Faraday Soc., 1944, 40, 488.82 Idem, ibid., 1952, 26, 1233.83 L. L. Bircumshaw and F. M. Tayler, J., 1950, 3674.84 S. 2. Roginskij, E. I. Shmuk, and M. Kushnever, Izuesti Akad. Nauk S.S.S.R.,Idem, ibid., 1946, 42, 468.B. V. Erofeev and I. I . Smirnova, Zhur. Fiz.Khirn., 1953, 25, 1098.1950, 57378 GENERAL AND PHYSICAL CHEMISTRY.decomposition temperature as that at which the maximum rate is attainedin 120 min., Roginskij et aZ.85 show that the electrostatic-potential term Ze/r,where r is the cation radius, 2 its valency, and e the electronic charge, is thepredominant factor. Cations with unfilled inner shells, however, have amarked specific effect in further lowering the decomposition temperature.Similar regularities are found with azides, formates, and oxalates.Chlorates and PerchZorntes.-Both Glasner and Sinichen,s6 and Bircum-shaw and Phillips 87 find two maxima in the rate of decomposition of potass-ium chlorate if chloride is present. With a small amount of chloride (eitheradded, or as a product), surface melting of the chlorate occurs and thedecomposition rate is accelerated.As the chloride content increases,resolidification with a consequent decrease in rate takes place. Glasnerdevelops an equation to account for his results based on the assumed mobilityof oxygen atoms in the lattice ; his expression includes terms characterizinga surface, and a simdtaneous bulk autocatalytic, process. Preliminarystudies of the breakdown of guanidine perchlorate 88 and of the Li, Na, K,Ca. Mn, and Fe salts have also been made.89hides.-Interest in this class of compound has been stimulated byMott’s applicationg0 of solid-state physics to the results of Wischin9l andof Garner and Maggsg2 on the thermal decomposition of barium azide;the theoretical treatment is similar to that postulated for the photodecom-position of silver bromide.W i s ~ h i n , ~ ~ using a photographic technique, hadshown that the rate of both nucleus formation and of three-dimensionalgrowth varied as the square of the time. The stable nucleus could, there-fore, be formed by the trapping of two electrons at an interstitial Ba2+ ion;similarly growth proceeds by further alternate trapping of eIectron pairsand mobile interstitial cations. However, the calculations based on measure-ment of the ionic conductance 93 of the salt and Wischin’s experimentallyobserved rates of growth do not support a theory of growth by internalelectrolysis, and reaction at the metal-salt interface is suggested. Detailedstudies of the kinetics of the photo- and thermal decornpo~ition,~~~ 95 coupledwith measurements of the photoconductance of the salt under irradiation,also show that few free electrons are produced, and a modified theoryinvolving “ uncharged ” mobile excitons, or excited azide ions, was proposed.Nucleus formation, following Mitchell,96 was conceived 97 as the aggregationof F-centres rendered mobile by the presence of anion vacancies, the stablenucleus being a double F-centre associated with a lattice Ba2+ ion.Pre-irradiation by ultra-violet light caused acceleration of the thermal processby producing anion vacancies, thereby increasing the mobility of F-centresand the rate of nucleus formation. The exciton theory was further de-85 S. Elovich, S. 2. Roginskij, and E.I. Shmuk, ibid., p. 469.8 6 A. Glasner and A. E. Simchen. Bull. SOC. chim., 1950, 18, 233.L. L. Bircumshaw and T. R. Phillips, J., 1963, 703.A. Glasner and L. Weidenfeld, J . Amer. Chenz. SOC., 1952, 74, 464.s9 G. G. Marvin and L. B. Woolaver, I n d . Eng. Chem. Anal., 1945, 17, 474.N. I;. Mott, Proc. Roy. SOC., 1939, A , 172, 325.91 A. Wischin, ibid., p. 314.92 W. E. Garner and J. Maggs, ibid., 1939, 172, 299.93 J. G. N. Thomas and F. C. Tompkins, J . Chem. Phys., 1952, 20, 662.O4 Idem, Proc. Roy. SOC., 1951, A , 209, 550.D6 J. W. Mitchell, Phil. Mag., 1949, 40, 249, 667.s7 F. C. Tompkins, I n d . Eng. Chem., 1952, 44, 1336.95 Idem, ibid., 1951, 210, 111TOMPKINS AND YOUNG: REACTIONS AT SOLID INTERFACES. 79veloped 98, 99 by the introduction of the concept of a coloration complex,100an entity resulting from the trapping of the excitation energy at an anionvacancy with a consequent quantum-mechanical tunnelling of the excitedelectron to the vacancy thereby forming a F-centre coupled to a positivehole. Pre-irradiation of the potassium salt, however, effected no thermalacceleration ; lol this was attributed to the production and evaporation ofpotassium atoms ; the catalytic effect of an atmosphere of potassium vapourduring decomposition is consistent with the lowering of the activationenergy 99 for the removal of the valency electron from the azide ion.Freeelectrons and positive holes can be produced, however, by using higherincident energies, e.g., by electron bombardment,lo2 and the kinetics displaynew features, such as a decrease of rate with time of bombardment and asubsequent slow recovery of the original rate.The critical decompositionenergy in electron bombardment is given as 11.65 ev.lo3 The ultra-violetemission taking place during thermal decomposition of alkali-metal andalkaline-earth azides, first noted by Audubert lo* by using photoelectriccounters, has been re-investigat ed. The activation energies derived fromthe tFmperature coefficient of emission agree with those obtained from thep-! curves of the thermal decomposition of sodium azide Io5 and silverazide lo6 at various temperatures. The emission is probably associated withthe bimolecular exothermic reaction of azide radicals producing activatednitrogen molecudes.Thus Haycock lo7 finds that nitrogen peroxide isproduced when silver azide is decomposed in an atmosphere of oxygen.Bowden and Singh l o 8 have found that neutron irradiation accelerates thethermal decomposition of lithium azide and lead azide, and Yoffe lo9 hasdiscussed the thermal decomposition, leading to explosion, of calcium andbarium azides.Misce2Zaneous.-The decomposition and explosive characteristics ofmercury fulminate l1O* ll1 and some nitrobenzenediazo-oxides 112 have beenstudied by Vaughan and Phillips. Although the Prout-Tompkins equationwas well obeyed, suggesting a branching mechanism for the fulminate, thep-t plots after an induction period are also consistent with the three-dimensional growth of a fixed number of nuclei.ll3Information concerning the initial stages of nucleation has been obtainedin the decomposition of lithium aluminium hydride 113 to lithium hydride,aluminium, and hydrogen.There is an initial surface reaction penetrating20-30 layers followed by an acceleration obeying a cube law. The hydrideis shown to be a semi-conductor ; on being heated, its conductance increases9 8 P. W. M. Jacobs and F. C. Tompkins, Pvoc. Roy. Soc., 1952, A , 215, 454.gs Ideni, ibid., p. 265.loo F. E. Schneider in “ Photographic Sensitivity,” Ed. J. W. Mitchell, Butter-worths Sci. Publ., 1951, p. 18. Iol ’CV. E. Garner and D. J . €3. Marke, J., 1936, 657.lo2 J . M. Groocock and F. C . Tompkins, Proc. Roy. Soc., 1934, A , in the press.lo3 R. H. Muller and G.C. Brous, J. Chew. Phys., 1933, 1, 482.lo4 R. Audubert, Trans. Faraday Soc., 1939, 35, 433.lo5 R. Audubert and J. Roberts, J. Chim. phys., 1946, 43, 127.lo6 R. Audubert, ibid., 1952, 49, 575.lo’ E. W. Haycock, private communication from W. E. Garner, Dec. 1953.lo8 F. P. Bowden and K. Singh, Nature, 1953. 172, 378.lo9 A. D. Yoffe, Proc. Roy. Soc., 1951, A, 208, 188.I1O J. Vaughan and L. Phillips, J., 1949, 2741.113 \V, E. Garner and E. W. Haycock, Proc. Roy. Soc., 1952, A , 211, 335.Idem, J.. 1949, 2736. 112 Idem, J . , 1947, 156080 GENERAL AND PHYSICAL CHEMISTRY.as F-centres diffuse into the lattice and then decreases near the end of theinduction period owing to the association of these centres which later formthe growth nucleus.The decomposition of mercurous formate,l14 magnesium hydroxide,l15ammoniacal and pyridine complexes of mercury ha1ides,ll6 and the chromatesof ammonium 117 has also been studied.F.C. T.D. A. Y.5. THE THEORY OF LIQUIDS AND LIQUID MIXTURES.Recent work has tended towards the elaboration of existing theoriesrather than the development of new concepts, but it is not yet possible toassess with any finality the merits of the different theoretical approaches. Ageneral survey of the literature dealing with the statistical mechanics andthermodynamics of the liquid state is likely, therefore, to be more usefulthan an exhaustive exposition of one or two particular topics. We haveomitted reference to papers dealing with transport phenomena, viscosity,surface tension, spectroscopic properties, and X-ray scattering because,although theoretical prediction of some of these properties is possible, theydo not form the most suitable criteria for assessing the validity of the theories.Furthermore, transport processes and viscosity have both been reviewedelsewhere recently.1sTheories of Pure Liquids.-Free-valztme, Lattice, or Cell Theory.-Theoriginal theory of Lennard-Jones and Devonshire has been modified byseveral authors to allow for the interchange of molecules between cells,for the non-occupation of cells, and for interaction between molecules whichare not nearest neighbours. These modifications have been reviewed andgeneralised in excellent papers by Rowlinson and Curtiss and by de Boer,5where references to earlier work will be found.The equilibrium concentra-tion of unoccupied cells (or “ holes ”) is evaluated by the quasi-chemicalmethod (cf. Guggenheim 6). This, together with a knowledge of the volumeof the cell, gives the effective free volume per molecule. Rowlinson andCurtiss chose values for the cell volume to fit the experimental data, whilede Boer obtained a theoretical value by minimising the free energy. A moreelegant treatment by Kirkwood allows the deduction of the free-volumetheory from the Gibbs configuration integral, subject to well-defined approx-imations, and leads to an integral equation for the probability density ($)within each cell of a reference lattice. t,b is related to the free volume. Inthis work no attempt is made to evaluate the “ communal entropy.’’ Afirst approximation to a solution of this equation yields a partition function1 1 4 G.A. Miller and G. W. Murphy, J . Amer. Chenz. Soc., 1951, ‘73, 1871.115 S. J . Gregg and R. I. Razouk, J . , 1949, S 36.116 D. R. Glasson and S. J. Gregg, J . , 1953, 1493.117 K. Fischbeck and H. Spingler. 2. anoi’g. Chem., 1939, 241, 209.1 R. Eisenschitz, PYOG. Roy. Soc., 1952, A , 215, 29.2 E. N. da C. Andrade, ibid., p. 36.3 J. E. Lennard-Jones and A. F. Devonshire, ibid., 1937, A , 163,63; 1938, A , 1 6 4 , l ;1939, A , 169,317. J. S. Rowlinson and C. F. Curtiss, J . Chem. Phys., 1951,19, 1519.J. de Boer, PYOC. Roy. Soc., 1952, A , 215, 4.E. A. Guggenheim, “ Mixtures,” Oxford, 1952, pp. 38 ff.J.G. Kirkwood, J . Chem. Phys., 1950, 18, 380CRUICKSHANK AND EVERETT: THE THEORY OF LIQUIDS. 81identical with that of the original treatment.3 havedeveloped Kirkwood’s approach by assuming the position of a moleculewithin its cell to be governed by a Gaussian distribution function and byallowing for the non-occupation of cells. Careri has shown that this approx-imation is good up to the critical point, while Wood lo has given an exactsolution for rigid spheres, and obtained an equation of state similar to thatobtained by Buehler et aZ.ll on the basis of the Lennard-Jones and Devon-shire theory. Lund l2 has suggested that Wood’s solution may apply totypes of molecular packing of rigid spheres other than the face-centred cubic.In general the cell theory gives an entropy for the liquid state which istoo low, but the precise way in which this extra entropy can be introducedinto the model is uncertain.5 On the other hand the cell theory is still themost convenient on which to base a theory of solutions.Molecular Distribution Function Approach.-The thermodynamic func-tions of liquids are related by the Gibbs theory of the canonical ensembleto the molecular distribution functionsnh(rl, .. . r h ) = ___- .Mayer and CareriN ! Je--m/kT drh+l. . . dr, b-@lkT dr, . . . drN( N - h ) !(cf. de Boer 13), where nh(rl, . . . rh) is the probability density of findingan arbitrarily selected set of h molecules in the configuration rl, . . . rh ; ri isthe vector defining the position of the ith molecule relative to a chosenorigin, and @ is the potential energy of the whole system.When <D can berepresented as the sum of potential energies between pairs, a knowledge ofthe pair distribution functions (closely related to the radial distributionfunctions obtained from X-ray scattering) as a function of density enablesthe thermodynamic functions to be calculated. In the theories of Kirk-wood and Boggs,14 Born and Green,15 Yvon,lG and Mayer,l79 l8 systems ofintegro-differential equations for the radial distribution function, formulatedin several equivalent forms, are solved approximately by means of the so-called superposition approximation. This work, together with the conse-quences of the superposition approximation, has been reviewed by de Boer(cf.also refs. 19, 20). Salsburg, Zwanzig, and Kirkwood21 have derivedexact expressions for the molecular distribution functions in a one-dimen-sional fluid, the molecules interacting with a nearest-neighbour pair potential ;the superposition approximation is exact in this case. McLellan 22 hasexpanded Born and Green’s equation for the radial distribution function asa power series in density. For a fluid of rigid spherical molecules the resultsJ. E. Mayer and G. Careri, J . Chenz. Phys., 1952, 20, 1001.G. Careri, ibid., p. 1114. lo W. W. Wood, ibid., p. 1334.l3 J. de Boer, Rep. Prog. Phys., 1949,12,305.l1 R. J. Buehler, R. H. Wentorf, J. 0. Hirschfelder, and C. F. Curtiss, ibid., 1951,19, 61.l2 L. H. Lund, ibid., 1952,20, 1977.l* J.G. Kirkwood and E. M. Boggs, J . Chem. Phys., 1942, 10, 394.l5 M. Born and H. S. Green, Proc. Roy. Soc., 1946, A , 188, 10.l6 J. Yvon, “ Actualit& Scientifiques et Industrielles,” Herman et Cie., Paris, 1935,l7 J. E. Mayer and E. Montroll, J . Chenz. Phys., 1941, 9, 2.l9 B. R. A. Nijboer and L. van Hove, Proc. K. hTed. Ahad. Wet., B, 1951, 54, 256;21 Z. W. Salsburg, R. W. Zwanzig, and J. G. Kirkwood, J . Chew Phys., 1963, 21,pp. 203 ff.Phys. Review, 1952, 85, 777.1098.J. E. Mayer, ibid., 1947, 15, 187.G. S. Rushbrooke and H. I. Scoins, Phil. Mag., 1051, 42, 582.22 A. G. McLellan, Proc. Roy. Soc., 1952, A , 210, 50982 GENERAL AND PXYSICAL CHEMISTRY.are in good agreement with those of Kirkwood, Maun, and Alder,23 obtainedby numerical integration, and with those of Rushbrooke and Scoin~.~*Kirkwood, Lewinson, and Alder 25 have evaluated the radial distributionfunction in Kirkwood’s and in Born and Green’s approximations for Lennard-Jones and Devonshire’s (6 : 12) interaction.The thermodynamic functionsderived therefrom are compared with experimental results for liquid argon.Because the thermodynamic functions are very sensitive to small changesin the distribution function the agreement is not entirely satisfactory.Zwanzig, Kirkwood, Stripp, and Oppenheim 26 give a method of modifyingthe theoretical distribution function so that one thermodynamic quantity(e.g., the pressure) agrees with its experimental value. They suggest that,in the absence of exact theoretical distribution functions, these empiricallyadjusted functions should be used for correlating thermodynamic data andfor calculating transport properties.Rushbrcoke and Scoins 27 have shown that the second approximationto the direct correlation function of scattering theory may be used to im-prove Born and Green’s approximation to the radial distribution function,and that this leads to a critical point at which PV/h7kT = 6.Kirkwoodand Salsburg 2* have developed a new system of integral equations for themolecular distribution functions based on partial cluster expansions of theMayer type.l7> 29-31 The new cluster expansions are of finite degree andthus converge for all densities. Earlier, Katsura and Fujita 32 had suggestedthat the unsatisfactory nature of Mayer’s cluster integral treatment forliquids (cf.ref. 17) is a result of ignoring the volume dependence of the clusterintegrals, and this dependence is discussed.The main shortcoming of the radial distribution function approach is thatnumerical results for comparison with experiment can be obtained only by veryextensive computations or by making simplifying assumptions whose effectson the validity of the theory are difficult to estimate. Experimental verifica-tion may be facilitated by an equation due to Zimm 33 connecting the chemicalpotential, the compressibility, andone of the pair distribution functionintegrals.CrystaZZite Theory.-Several years ago O ~ k a w a , ~ ~ following Frenkel,35developed a semi-empirical theory in which a liquid at low temperatures isconceived as a mosaic of crystallites in contact along interfaces with whichare associated a boundary energy.An attempt was made to interpret theheat capacity of liquids, of which there is no satisfactory theory, and todiscuss the solid-liquid transition and the viscosity. Ookawa now claims 36that identification of the boundary energy with a free energy improves theagreement with experiment.23 J. G. Kirkwood, E. K. Maun, and B. J. Aider, J . Chenz. Phys., 1950, 18, 1040.24 G. S. Rushbrooke and H. I. Scoins, Nature, 1951, 167, 366.25 J. G. Kirkwood, V. A. Lewinson, and B. J. Alder, J . Chein. Phys., 1952, 20, 929.26 R. \V. Zwanzig, J. G. Kirkwood, K. F. Stripp, and I. Oppenheim, ibid., 1953, 21,28 J. G. Kirkwood and 2.W. Salsburg, Discuss. Faraday Soc., 1953, 15, 28.29 J. E. Mayer and S. F. Harrison, J . Chewa. Phys., 1938, 6, 87.3O J. E. Mayer, ibid., 1942, 10, (329;31 J. E. Mayer and M. G. Mayer,33 B. H. Zimm, ibid., 1953, 21, 934.34 A. Ookawa, .J. Phys. SOC. Japan, 1947, 2, 108; 1948, 3, 295; 1949, 4, 14.35 J . Frenliel, “ Kinetic Theory of Liquids,” Oxford, 1946.s 6 A. Oolrawa, J . Plays. SOC. Japan, 1952, 7, 543.1268. 2 7 G. S. Rushbrooke and H. I. Scoins, Pvoc. Roy. Soc., 1953, A , 216, 203.Statistical Mechanics,” Wiiey, New York, 1940,Ch. 13. 32 S. Katsura and H. Fujita, J . Chem. Phys., 1951, 19, 795CRUICKSHANK AND EVERETT: THE THEORY OF LIQUIDS. 83Associated Liquids.-Intermolecular potential energies which are func-tions of the relative orientations of the molecules have been reduced by Cookand Rowlinson 37 to a form similar to that for simple spherical moleculesby taking a statistical average over all configurations.On the other hand,Stockmayer38 and Rowlinson39 have evaluated the free energy of polarliquids as a sum of the free energy for the liquid, neglecting dipole inter-action, plus a dipole-interaction term. Pople 40 has used Kirkwood'smethod 7 for the first term, and a model of freely-rotating dipoles fixed onlattice sites for the second. Dipole interaction alone is found to be insuffi-cient to account for the difference between polar liquids and similar non-polar liquids. The theory has been extended 41 to the case of simultaneousdipole and quadrupole interactions, and some general conclusions are drawnapplicable to all types of directional forces.Liquid Mixtures-Regular SoZ~tions.-Guggenheim (ref.6, Ch. I11 andIV) has defined a strictly regular solution as one in which the molecules ofthe different species pack in the same manner as in the pure components,and in which the interaction between the species may be assumed not toalter the internal partition fuiictions or the acoustic factor in the translationalpartition functions (cf. Guggenheim 42), These restrictions reduce the cal-culation of the excess thermodynamic functions" of the solution to theevaluation of the configurational partition function. This was first doneon the basis of a fixed lattice model using the quasi-chemical approx-imation, which is equivalent to assuming the non-interference between pairsof occupied sites.Guggenheim et aL6 have shown that higher approx-imations, obtained by considering non-interference of larger local groupsof sites, do not differ greatly from the pairs approximation, but apparentlyconverge slowly. However has proved formally that they doconverge ultimately and has suggested an alternative generalisation of thequasi-chemical treatment which gives results identical with those of KikuchL44For two-dimensional lattices, for which exact results are known, Barker'smethod is an improvement on the quasi-chemical approximation, and itmay be presumed to be so in other cases also. The method used by Guggen-heim et aL6 to normalise the combinatory factor in regular assemblies hasbeen modified by Prigogine, Mathot-Sarolea , and van Hove.45 Onsager'smethod 46 is used to calculate the exact combinatory factor for square andtriangular plane lattices, and an extra parameter is introduced into theGuggenheim normalising factor to make it exact for the perfectly orderedstates, leading to a good estimation of the critical tem~erature.~737 D.Cook and J. S. Rowlinson, Proc. Roy. Soc., 1953, A , 219, 405.38 W. H. Stockmayer, J . Ckem. Phys., 1941, 9, 398.39 J. S. Rowlinson, Tyans. Faraday Soc., 1949, 45, 984.4o J. A. Pople, Proc. Roy. Soc., 1952, A , 215, 67.41 J. A. Yople, Discuss. Faraday Soc., 1953, 15, 35.42 E. A. Guggenheim, ibid., p. 24. 43 J. A. Barker, Proc. Roy. SOC., 1953, A , 216,45.44 R.Kikuchi, Phys. Review, 1951, 81, 988.45 I. Prigogine, L. Mathot-Sarolea, and L. van Hove, Trans. Faraday Soc., 1953,48, 485.4 7 L. Mathot-Sarolea, " Changements de phases," Compt. rend. 2e Reunion deChimie physique, SOC. Chim phys. (Paris 1952) [referred to later as " Changements dephases "I, p. 197. * The excess thermodynamic function is defined as the amount by which the valueof the corresponding function in a real solution exceeds that which i t would have if thecomponents formed a perfect solution.4 6 L. Onsager, Plays. Review, 1944, 65, 14084 GENERAL AND PHYSICAL CHEMISTRY.The quasi-lattice theory takes no account of the volume change of mixingand consequently is not satisfactory for evaluating thermodynamic functionsin systems where volume changes occur (cf.Longuet-Higgins *9. A steptowards overcoming this limitation has been taken by applying the celltheory of Lennard- Jones and Devonshire to regular solutions. Prigogineand Garikian 49 suppose each molecule to vibrate as a harmonic oscillatorwithin a cell, while Prigogiiie and Mathot 50 have used a square-well poten-tial, which they claim best fits the experimental data. Assuming randomdistribution of the various types of pairs, they have evaluated the volumeof mixing and its effect upon the heat of mixing and excess entropy ofregular solutions. Reasonable agreement with experiment has been ob-tained.51 The effect of non-random mixing has been studied by Sarolea,52but is considered not to affect the conclusions of the previousNasielski 53 has calculated the partial molar quantities corresponding to thismodel.Pople 54 has employed a 6 : 12 interaction in the cell theory ofregular solutions and has taken account of non-random mixing. Thetheory is claimed to be an improvement on that of Prigogine and M a t h ~ t , ~ obut is unable to account quantitatively for the experimental values ofthe excess entropy in some simple systems in which it is suggested thatmutual orientation effects are significant. R o ~ l i n s o n , ~ ~ in a more generaltreatment, expresses the free volume in terms of the cell dimensions for thepure components, the interaction energy, and the composition. The quasi-chemical approximation is again used. Four approximate solutions to theproblem are discussed.The first, by the assumption that the free volumesare independent of the mixing process, leads to the strictly regular solutiontheory, the second to Ono’s results,56 and the third to those of Prigogine andGa~-ikian.~~ The fourth, probably the most accurate, gives results for thevolume change on mixing in agreement with the conformal solution theory,57the latter being essentially a first-order perturbation from the ideal solution(cf. also Prigogine 58). Salsburg and Kirkwood 59 have extended theprevious work to multi-component mixtures, expanding the Gibbs configur-ation integral by the method of moments. Retention of the first moment(corresponding to random mixing) and use of an approximate smoothedpotential is said to yield the results of Prigogine and Garikian.49 An altern-ative approximation for the first moment, but with a 6 : 12 interaction, isderived.It is pointed out that until the restriction of equal molecular sizecan be overcome, and the problem of “ communal entropy ” solved, furtherelaboration of the theory is of minor practical importance. Rowlinson 60has attempted to assess the relative merits of the various cell theories byusing them to evaluate equations of state for a pure liquid. He concludes48 H. C. Longuet-Higgins, Ann. Reports, 1951, 48, 73.49 I. Prigogine and G. Garikian, Physica, 1950, 16, 239.6o I. Prigogine and V. Mathot, J . Chem. Phys.. 1952, 20, 49.51 V. Mathot and A. Desmyter, ibid., 1953, 21, 782.52 L. Sarolea, J . Chem. Phys., 1953, 21, 182; see also ref.9.53 J. Nasielski, ibid., p. 184.6 5 J. S. Rowlinson, Proc. Roy. SOL, 1952, A , 214, 192.S. Ono, Mem. Fac. Eng. Kyushu, 1950, 12, 201.5 7 H. C. Longuet-Higgins, Proc. Roy. SOC., 1951, A , 205, 247.5 8 I. Prigogine, “ Changements de phases,” p, 97.59 Z. W. Salsburg and J. G. Kirkwood, J . Chem. Phys., 1952, 20, 1538.6o J. S. Rowlinson, Discuss. Faraday SOG., 1963, 15, 52.54 J. A. Pople, Trans. Fwaduy SOC., 1953, 49, 591CRUICKSHANK AND EVERETT: THE THEORY OF LIQUIDS. 85that only the 6 : 12 interaction applied over all neighbours of a given mole-cule is likely to give satisfactory agreement with experiment. The restric-tion of equal molecular size (cf. ref. 59) has been relaxed in a new treat-rnent.61, 62 It is shown that the sign of the volume of mixing is dependenton the ratio of the molecular sizes and the nature of the intermolecularforces.Some anomalies in the earlier theory 49-51 are thereby removed.Rushbrooke63 has shown that Born and Green’s equations for binarymixtures are related to certain approximations to the integrals in Mayer andMontroll’s l 7 expansions of the radial distribution functions in powers ofdensity and composition. Ono 64 has used a method previously developed 65to derive the generalised Born and Green equations for solutions of electrolytesand non-electrolytes, using the superposition approximation. The resultingequations may be used to compute the deviation from ideal-solution be-haviour if the potentials of the mean force at infinite dilution are known.Adifferent approach has been developed by Kurata 66 who has derived on akinetic basis equations for the vapour pressure of a regular solution whichagree with those derived by statistical methods.Co-operatine Orientation Efects.-Miinster 6 7 has evolved a statisticaltheory of binary mixtures in which one component is subject to co-operativeorientation ; this has been applied to the system ben~ene-cyclohexane,~~ (c)and, with a semi-empirical correction to the theory of polymer solutions, tothe system benzene-rubber.68 In both cases there is good agreement withthe experimental excess free energy, the values of the molecular orient-ation energy of benzene which give the best fit being identical, and in fairagreement with that calculated quantum-mechanically .6g Tompa 70 hasapplied essentially the same concept to regular solutions, using the simplercombinatory method (ref.6, Ch. IV) instead of the local grand partitionfunction method.67 Barker 71 has used the conformal solution method 56to obtain the excess free energy of mixing of a binary system in which onecomponent displays weak dipole interaction, in terms of the properties ofthe pure dipolar component. In an approximate treatment of solutions ofalcohols, Barker 72 has applied a method of direct enumeration of configur-ational probabilities, similar to that used by Guggenheim (ref. 6, p. 193), toa formalised model of spherical molecules with tetrahedrally disposed inter-actions and arranged on a three-dimensional lattice.I t is concluded thata more general treatment of the three-dimensional array might providea satisfactory basis for the complete description of the experimental facts.The quasi-chemical treatment has been applied in a manner similar tothat of Munster 679 68 to this model, the approximations being checked againstthe conformal solution method.71 Reasonable agreement with the experi-mental data is found. A qualitative interpretation of both upper and lowerconsolute temperatures is also given. The accuracy of this quasi-chemicalI. Prigogine and A. Bellemans, J . Chem. Phys., 1953, 21, 561.62 I d e m , Discuss. Faraday Soc., 1953, 15, 80.63 G. S. Rushbrooke, Phil. Mag., 1952, 43, 1276.64 S. Ono, Prcg. Theor. Phys. Japan, 1951, 6, 447.6 5 I d e m , ibid., 1950, 5, 822.6 6 M. Kurata, Bull. Soc. Chem. Japan, 1952, 25, 363.67 A. Miinster, ( a ) Trans. Faraday Soc., 1950, 48. 165; ( b ) 2. Electrochem., 1950, 54,68 Idena, Trans. Favaday SOC., 1953, 49, 1.69 J. de Boer, ibid., 1936, 32, 10. ‘O H. Tornpa, J . Chenz. Phys., 1963, 21, 250.71 J. A. Barker, ibid., 1951, 19, 1430.71 I d e m , ibid., 1952, 20, 794. 73 Idem, ibid., p. 1526.443; ( c ) 2. Physikal. Chem., 1950, 196, 10686 GENERAL AND PHYSICAL CHEMISTRY.approximation has been examined 74 and higher approximations are derivedby the methods quoted in ref. 43. The quasi-chemical approximation forpairs is satisfactory for lattices other than close-packed. Barker 75 hasalso calculated the electrostatic energy of a system of molecules with per-manent and induced dipoles as a power series in the polarisabilities, thefirst and second moments of the electrostatic energy being evaluated to thefirst order in polarisability. These are used to give approximate expressionsfor the contribution of the electrostatic forces to the free energy of polarliquids and solutions. Pople 41 has extended his theory 40 of associated liquidsto include mixtures, while Sarolea-Mathot, 76 developing earlier work,77 hasdiscussed the thermodynamic properties of associated solutions in terms of thechange in the number of orientations on formation of a molecular complex.Mixtures of Single and Mu.tiple Molecules. Polymer Solutions.-The majordifficulty in calculating the thermodynamic properties of these mixturesremains that of deriving an adequate expression for the free energy of aso-called athermal solution, in which all configurations have the same internalenergy. From this it is possible,6 by using the quasi-chemical approxim-ation in pairs, to calculate the thermodynamic properties of interactingassemblies. Rushbrooke, Scoins, and Wakefield 78 have expanded therestricted grand partition function for an assembly of N , monomers andN, r-mers occupying ( N , + rN,) sites by Mayer’s cluster integralExpressions are derived for the partial vapour pressures of the two com-ponents as a power series in the volume concentration 0 of the larger species.The coefficients of successive powers of 8 are shown to be analogues of thefunctions P k of Mayer’s theory. The simplest approximation to P k leads toFlory’s vapour pressure equations, and the next most simple to those ofMiller and Guggenheim (cf. ref. 6, pp. 205 ff., pp. 193 ff.). An accurateexpression for p k is given, and for a monomer-dimer solution a sufficient numberof p’s have been calculated to give close estimates of the best solution withinthe limitations of the model. The theory gives good agreement with theexperimental values of the activity coefficient of benzene in mixtures ofbenzene and di~henyl.7~ Guggenheim 80 has pointed out (cf. McMillan andMayer 81) that in the evaluation of the cluster integrals Zimm 82 and Hug-gins 83 treat the solvent effectively as a continuum. This is justified onlyif the solute molecules are very much larger than those of the solvent. Ifthis is not so it is necessary to use a lattice model to obtain tractable mathe-matical relations. The cell theory has been extended to mixtures of r-mersand monomers 843 85 by assuming a quasi-crystalline lattice with the elementsof the r-mer as interacting point centres. The first paper assumes a square-well cell potential, and the second a potential of the harmonic-oscillatortype. In both cases the thermal factor is introduced through the quasi-74 J. A. Barker, J . Chenz. Phys., 1953, 21, 1391.7 5 Idem, Proc. Roy. SOL, 1953, A , 219, 367.76 L. Sarolea-Mathot, Trans. Faraduy SOL, 1953, 49, 8.7 7 I. Prigogine, V. Mathot, and A. Desmyter, Bull. SOC. chim., Belg., 1949, 58, 647.78 G. S. Rushbrooke, H. I. Scoins, and A. J. Wakefield, Discuss. Furaduy SO^.,O 9 D. H. Everett, ibid., p. 114.s1 W. G. McMillan and J. E. Mayer, J . Chem. Phys., 1945, 13, 276.8 2 B. H. Zimm, ibid., 1946,14,164.84 V. Mathot, “ Changements de phases,” p. 115.6 5 I. Prigogine, N. Trappaniers, and V. Mathot, Discuss. Faraday SOC., 1953, 15, 93.1953, 15, 57.E. A. Guggenheim, ibid., p. 68.83 M. L. Huggins, J . Phys. Chern., 1948, 52,248CRUICKSHANK AND EVERETT: THE THEORY OF LIQUIDS. 87chemical method (cf. ref. 6, Ch. XI). This treatment makes it possible tostudy the excess thermodynamic functions which result from the changesin the mean field caused by mixing. It is shown 84 that the contribution tothe excess properties caused by the variation of mean field with concen-tration can be quite large in the case of r-mer-monomer mixtures. Analternative approach which avoids the concept of the potential of the meanforce has been given by Tchimura.86Longuet-Higgins 87 has introduced an ingenious approximation basedon the assumption that the probability distribution function for a pair ofends belonging to different molecules depends only on temperature anddensity and not on the lengths of the molecules. He obtains an expressionfor the Gibbs free energy of mixing in a binary mixture of different types ofchain molecules which is independent of the restrictive assxmptions implicitin the quasi-lattice theory, provided that the two types of molecules aresufficiently long. I t also provides a theoretical interpretation of Brransted'sprinciple of congruent mixtures.88Critical Phenomena.-There are two opposing views of the nature of thecritical region, and the situation has been rather obscured by some ambiguityin the experimental findings. In a comprehensive review 89 Mayer hasre-affirmed his opinion that the liquid-vapour co-existence curve in the P-Vdiagram is flat-topped and that isotherms have a horizontal portion for arange of temperature above that at which the meniscus disappears. Asimilar behaviour is predicted for the co-existence curve of two liquid phasesat an upper critical solution temperature.have investigated the co-existence curve of very pure xenon in both long andshort tubes mounted vertically and conclude that in the limiting case of atube of zero height there would be a unique critical point. Further work 91with a long thin tube mounted alternately in vertical and horizontalpositions confirms the large influence of gravitation on the form of the co-existence curve. Murray and Mason ga have studied the gravitationaleffect in ethane by light-scattering methods, and Schneider 91 that in xenonby using radio-xenon as a tracer. MacCormack and Schneider 93 found noevidence for the anomalous second-order transition in sulphur hexafluorideabove the temperature at which the meniscus disappears. Co-existencecurves of binary liquid mixtures do not seein to have been studied withsufficient precision to allow any final conclusions to be reached.94 Theultrasonic absorption of xenon,95 sulphur he~afluoride,~~ and some binarysystems 97 has been studied. A maximum in the attenuation at the criticalWeinberger and Schneider8 6 H. Ichimura, J . PJzys. SOC. Japan, 1952, 7, 152.8 7 H. C. Longuet-Higgins, Discuss. Faraday Soc., 1953, 15, 73.89 J . E. Mayer, " Changements de phases," p. 35.91 W. G. Schneider, " Changements de phases," p. 69.92 F. E. Murray and S. G. Mason, Canad. J . Clzem., 1962, 30, 550.s3 K. E. MacCormack and W. G. Schneider, ibid., 1951, 29, 699.94 R. W. Rowden and 0. K. Rice, " Changements de phases,s5 A. G. Chynoweth and W. G. Schneider, J . Chein. Phys., 1952, 20, 1777.96 W. G. Schneider, ibid., 1950, 18, 1300; Canad. J. C h e w , 1951, 29, 243.9 7 A. G. Chynoweth and W. G. Schneider, J . Chcm. Phys., 1951, 19, 1566;20, 760; G. F. Alfrey and W. G. Schncider, Discziss. Faraday SOC., 1053, 15, 218.J. N. Brernsted and J. Koefoed, KzZ. Danske Viaem. Selsk., 1946, 26, no. 17.M. A. Weinberger and W. G. Schneider, Canad. J . Chem., 1952, 30, 422.p. 78; D. Atach and0. K. Rice, Discuss. Faraday Soc., 1953, 15, 210; B. H. Zimm, J . Chew. ,rhys., 1952,20, 538. pp. 66, 91. See also general discussion of papers in " Changements de phases,195288 GENERAL AND PHYSICAL CHEMISTRY.point is ascribed to configurational relaxation processes. Michels andStrijland 98 have shown that near the critical point the molar heat capacitya t constant volume of carbon dioxide can have abnormally large values. Theresults are explained in terms of clusters in the gas and holes in the liquid.Calorimetric determinations of the molar heat capacity a t constant pressurenear the critical point of binary solutions have also been reportedJg9 andsimilar phenomena are observed. The viscosity of binary liquid systemsalso shows a maximum near the critical temperature.100There have not been any recent purely theoretical developments con-cerning the existence of an anomalous region near the critical point althoughRocard lol has claimed that by an empirical modification of the law ofattraction between hard spheres it is possible to account for Schneider’sexperimental results. The experimental evidence seems to indicate, how-ever, that the anomalous region, if it exists, occupies an exceedingly smalland possibly undetectable area of the P-V diagram. In a series of briefpapers van Dranen lo2 has investigated the hypothesis that at the criticalpoint the kinetic energy of the molecules is equal to their negative potentialenergy so that the total internal energy, relative to the molecules at rest atinfinite separation, is zero. Calculations based on models of the liquid andthe gas state support this idea, but it is too early to assess its validity. Notheoretical basis for it has been advanced.Further developments have been made in the theory of critical-solutiontemperatures in binary liquids especially with reference to lower consolutepoints. A discussion of the cell model lo3 shows that molecules withspherically-symmetrical force fields cannot show a lower critical temperatureand that this phenomenon is associated with the existence of orientationeffects. Barker and Fock l o 4 have made a more detailed study of thisproblem in relation to several specific models. The thermodynamic char-acteristics of systems exhibiting critical solution phenomena have also beendiscussed. lo5A. J. B. C.D. H. E.A. S. CARSON.E. COLLINSON.A. J. B. CRUIKSHANK.F. S. DAINTON.D. H. EVERETT.K. J. IVIN.J. W. LINNETT.F. C. TOMPKINS.D. A. YOUNG.gs A. Michels and J. Strijland, “ Changements de phases,” p. 87.O9 V. K. Semenchenko and E. L. Zorina, Doklady Akad. Nauk S.S.S.R., 1950, 73,2 ; V. K. Semenchenko and V. P. Skripov, Zhur. Fiz. Kkim., 1951, 25, 362; G. Jura,D. Fraga, G. Maki, and J. H. Hildebrand, PVOC. Nut. Acad. Sci., 1953, 89, 19.loo V. K. Semenchenko and E. L. Zorina, ?;kZady ARad. Nauk S.S.S.R., 1951,80,903.l01 Y. Rocard, “ Changements de phases,lo2 J. van Dranen, J . Chem. Phys., 1952, 20, 1175; 1953, 21, 567, 1404.lo3 I. Prigogine, ‘‘ Changements de phases,” p. 95; A. Bellemans. J. Chem. Phys.,lo* J. A. Barker and W. Fock, D~SCUSS. Faraduy SOC., 1953, 15, 188.Io5 J. L. Copp and D. H. Everett, ibid., p. 174.p. 45.1953, 21, 369

ISSN:0365-6217    

DOI:10.1039/AR9535000009

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

INORGANIC CHEMISTRY.PROGRESS in the quantitative interpretation of the relative stabilities ofmetal complexes has been well maintained, and several important papers ofa general nature have appeared during the year.A large volume of work on diborane and borohydrides, carried out aboutten years ago, and awaited with much interest, has now been published.Some interesting new silicon hydrides have been prepared, e.g., S(SiH,),and P(SiH,),.There have been substantial developments in the chemistry of nitrogen,phosphorus, and sulphur, notably the discovery of the blue unstable com-pound " imine '' (NH), and the new allotropes, brown phosphorus and bothpurple and green sulphur; studies on the sulphur nitrides have progressedconsiderably and two new oxynitrides have been prepared.Progress in the chemistry of fluorine has included the preparation ofinteresting trifluoromethyl (CF,) derivatives of sulphur, phosphorus, andarsenic, and a new oxyfluoride of iodine (10,F).Greatly improved methods, using liquid ammonia, for the preparationof metal cyclopentadienyls have been used to obtain several new membersof this particularly interesting class of compound.Carbonyls, which arenow of much industrial importance, e.g., in connection with hydrof ormylationand carbonylation reactions, have received much attention, in particular thesubstitution of CO by other groups such as isocyanides, and the reactionsbetween carbonyls and organic compounds.Review articles have been published during the year on stratosphericair,l the action of nitric acid on metals,, protactini~m,~ the stereochemistryof nickeland other simple inorganic compounds,7 and inorganic chromatography.sAccurate heats of formation have been obtained for the oxides of tin,glanthanum, cerium,1° and hafnium,ll and vapour-pressure data for galliummetal,12 the iodides of boron and silicon,13 titanium tetrachloride l4 anduranium he~aflu0ride.l~ Other data are mentioned in later sections.Complexes.-A critical review of new and previously published data on thestability of complexes formed by bivalent ions of the first transition series hasshown that the Irving-Williams order Mn < Fe < Co < Ni < Cu > Zn holdsfor nearly all such complexes irrespective of the nature of the co-ordinatingligand and even of the number of molecules involved.This seems to be aand hexacovalent complexe~,~ the thermochemistry of oxidesF. A. Paneth, Bull. SOC. chim., 1953, 20, 1.E. Abel, 2. anorg. Chem., 1952, 271, 76.G. L. Miles, Revs. Pure Appl. Chem. (Australia), 1952, 2, 163. * R. S. Nyholm, Chem. Reviews, 1953, 53, 263.F. Basolo, ibid., 52, 459. L. Brewer, ibid., p. 1.L. H. Long, Quart. Reviews, 1953, 7, 134. R. A. Wells, ibid., p. 307.G. L. Humphrey and C. J. O'Brien, J . Amer. Chem. SOC., 1953, 75, 2805.l o E. J. Huber and C. E. Hollev, ibid., pp. 3594, 5645.l1 G. L. Humphrev, ibid., p. 2806.l2 R. Speiser and H. L. Johnston, ibid., p. 1469.l3 H. C. Andersen and L. H. Belz, ibid., p. 4825.l4 H. Schafer and F. Zeppernick, 2. anorg.Chew., 1953, 272, 274.l5 G. D. Oliver, H. T. Milton, and J. W. Grisard, J . Amer. Chem. Soc., 1953, '75, 282790 INORGANIC CHEMISTRY.consequence of the fact that the two parameters which serve as a measureof the electrostatic and covalent interactions respectively, vix., the reciprocalof the ionic radius and the second ionisation potential (M __t M2+), bothincrease monotonically throughout the series Mn to Cu. Since the processof co-ordination results in a decrease in formal charge, M2+ _+ MO, a metalof high second ionisation potential (it?., a cation of high electron affinity)will form more stable covalent complexes than one of lower ionisationpotential. The sudden drop in stability from copper to zinc is explainedin this way. Similarly the stability orders proposed by other workers toinclude, e.g., Zn, Cd, Pb, Mg, and other metals have no universal validityand even among a group of closely similar elements such as Mg, Ca, Sr, andBa the order of stability depends on the nature of the ligand. While com-plexes of ferrous iron with, e.g.ethylenediamine, salicylaldehyde, or glycineare about as stable as, or weaker than those of zinc and cadmium, its stronglycoloured diamagnetic complexes with 1 : 10-phenanthroline and 2 : 2’-dipyridyl are disproportionately stronger. This is explained by “ orbitalstabilisation” (see also ref. 317). Entropy and steric factors have alsobeen considered.16A quantitative but empirical relation has been discovered between theformation constant of a bivalent metal complex and the ionisation potentialof the metalJ17 and the methods available for computing successive formationconstants have been critically considered and improved.l8Steric influence on stability is shown by the relative stabilities of theferrous complexes of methyl-substituted 1 : 10-phenanthrolines. The 2 : 9-dimethyl compound does not form a ferrous complex, and/-\- the 2-methyl derivative [although a stronger base than />=< 2\ the parent (I)] forms a weak bis-complex, while (I) gives ‘‘d N-/ mainly the red tris-comple~.~~ Steric factors also influencethe stabilities of complexes formed by the hexadentate ligand 2o(NH2~CH2~CH,),N-CH2~CH2*N(CH2-CH2~NH,)2, which is only tetra- or penta-dentate to Cu, Zn, and Hg. Complex salts, considered to contain 7-, 8-,and 9-membered rings, have been prepared from cupric, silver, and mercuricperchlorates and NH,*[CH,] ;NH, (TZ = 4, 5, or 6).21The entropy factor has been studied in connection with several complexions.The heats of formation of the ions Cd(NH,),? +, Cd(NH,*CH,),++, andCden++ are almost identical, the greater stability of the (en) complex beingentirely due to the entropy factor, as has been suspected for some time.The same is true of the ions Cd(NH,),+ +, Cd(NH2*CH3)a+T, and CdThe six entropy changes in the successive reactions in the formation of theAlFa3- ion decrease with remarkable regularity ; heat and free-energydata have also been obtained.23Although potentiometric titration methods have been extensively used(I)H.Irving and R. J. P. Williams, I . , 1053, 3192; Analyst, 1952, 77, 813. c. L. Van Panthaleon Van Eck, &zc. Trav. chzm., 1953, 72, 50, 529.H. Irvingand H. S. Rossotti, J . , 1953, 3397; J. C. Sullivan and J. C. Hindman, J .Anter. Chein. SOG., 1952, 74, GO91 ; B. P. Block and G. H. Mclntyre, ibid., 1953, 75, 5667.Is H. Irving, 1%. J . Cabell, and D. H. Mellor, J., 1953, 3417.2o G. Schwarzenbach and P. Moser, Helv. C h i m Acta, 1953, 36, 551.2 1 P. Pfeiffer, E. Schmitz, and A. Bohm, 2. anorg. Chem., 1952, 270, 287.22 C . G. Spike and R. W. Parry, J . Amer. Chenz. SOC., 1953, 75, 27%.23 W. M. Latimer and U7. L. Jolly, ibid., p. 1548COATES AND GLOCKLING. 91to examine the relative stabilities of complexes, many particularly interestingcompounds are insoluble in water.Attempts to overcome this difficultyby the use of water-alcohol or water-dioxan mixtures complicate theinterpretation of potential measurements. Thermodynamic aspects of thisproblem have now been ~tudied.~4 The dissociation and stability constantsof fifteen p-diketones and their copper, nickel, and barium complexes havebeen compared in water-dioxan solution,25 and in one case an alcoholicsolution was compared with a water-dioxan mixture of the same dielectricconstant .26Tropolone forms metal complexes whose order of stability is similar tothat of other ligands ; several of its complexes are insoluble.27Solutions of complex anions free from metallic cations have beenobtained by the use of ion-exchange resins.Of the complex acids(H30i )3[Cr(C204)3]3-, only the last could be obtained in a crystalline state(blue needles). A similar procedure was used to prepare the salt[Co(NH,),] [Co(CO,),] from the green solution resulting from the oxidationof CO(II) salts in the presence of excess of alkali hydrogen carbonate.28Thermodynamic data have been obtained for the reversible formationof the bispen t anedionediaquomanganese (11 I) cation from t rispent anedione-manganese(~n).~~Formation constants have been determined for lead citrate complexes,30the Pb(N0,) + uranyl glycol late^,^^ complexes of copper and cobalt withphthalic, malonic, and other chelate acids,,, complexes of a series mainlyof bivalent metals with various p-diketone~,~~ digly~ylethylenediamine,~~nitrilotricarboxylic a ~ i d s , ~ 6 iminopropionic and aspartic acids,37 ethylene-diamine-acetic and -propionic acids,,8 and [CH2(OH)*CH2]2N*CH2-C02H.39A large number of metal-nicotine complexes has been prepared.40 Thebisthiosemicarbazones of a-diketones (NH,=CS*NH*N:CR), form highlycoloured, insoluble complexes with niany heavy metals [e.g., CU(II), Ni(iI),P ~ ( I I ) ] .~ ~Group 1.-The blue solution of lithium in methylamine decomposes at50-60" into lithium methylamide, LiONHCH,, and hydrogen. The amideis a white powder, almost insoluble in methylamine, and insoluble in etherand benzene. It reacts with various halides (even bromobenzene) givingN-methylamines, CH,*NHR.42 The series of ternary lithium nitrides hasH3O- [ co (N H3) 2 (No&]-, H30t [ Cr (NH3) 2 (SCN),]-, (H30+)3[CO( C204) 31 and24 L.G. Van Uitert and C. G. Haas, J . Amer. Chem. SOC., 1953, 75, 451.25 L. G. Van Uitert, W. C. Fernelius, and B. E. Douglas, ibid., pp. 455, 457.2 6 Idem, ibid., p. 3577.2 7 B. E. Bryant, W. C. Fernelius, and B. E. Douglas, ibid., p. 3784.28 T. P. McCutcheon and W. J. Schuele, ibid., p. 1845.29 G. H. Cartledgc, ibid., 1952, 74, 6015.30 M. Bobtelsky and B. Graus, ibid., 1953, 75, 4172.31 H. M. Hershenson, M. E. Smith, and D. N. Hume, ibid., p. 507.32 S. Ahrland, Acta Clzenz. Scand., 1963, 7, 485.33 hl. Bobtelsky and I. Bar-Gadda, Bull. SOC. chim., 1953, 20, 276.34 L. G. Van Uitert, W. C. Fernelius, and B. E. Douglas, J . Amer. Chem. SOC., 1953,3 5 A. K. Chakraburtty, N.N. Ghosh, and P. R%y, J . I n d i a n Chem. SOC., 1953, 30, 185.36 S. Chabereb and A. E. Martell, J . Amer. Chem. SOC., 1953, 75, 2888.37 Idem, ibid., 1952, 74, 6081.39 S. Chaberek, R. C. Courtney, and A. E. Martell, ibid., 1963, 75, 2188.40 C. R. Smith, ibid., p. 2010.42 R. Juza and E. Hillenbrand, ibid., p. 297.75, 2736, 3739, 3862.38 I d e m , ibid., p. 6228.41 G. Bahr, 2. anorg. Chem., 1953, 273, 32692 INORGANIC CHEMISTRY.been extended to some Group IV elements and now includes Li,SiN,, Li,TiN,,and Li,GeN,, as well as some oxynitrides, e g . , Li5TiN,,2Li,0.43The vapour-pressure equations of the chlorides of potassium, rubidium,and czsium have been obtained by measurement of rates of sublimationin a stream of nitrogen. The latent heats of sublimation, of interest inconnection with lattice energies, are KC1 50.2, RbCl 46.4, and CsCl 44.1k~al./mole.~~ The systems NaC1-SrSO, (or BaSO,) resemble NaCl-CaSO,in not forming either solid solutions or double salts, but there is completeliquid mi~cibility.~~A recent measurement of the vapour pressure of copper has resulted ina new value, 81-08 kcal./g.-atom, for the latent heat of vaporisation atSolutions of cuprous chloride in concentrated hydrochloric acid absorbacetylene without colour change ; the acetylene probably retains its hydro-gen, and the addition compounds appear to contain one molecule of acetyleneand one atom of copper.Neutral solutions of cuprous chloride in alkalichlorides absorb acetylene with the formation of a bright yellow colour;in this case copper appears to be substituted for hydrogen, giving an acetylide.The species CuC1, -, CuCl,=, C,H,,Cu+, C,H,,CuCl, and C,H,,CuCl,- havebeen identified in the colourless solutions, and their formation constantsmeasured.47A series of copper(rr) pyrophosphates, [CU(P,O~),]~-, [CUP,O,]~-,[CU,P,O,]~, and [Cu,P,O,]++, has been detected by light-absorption experi-m e n t ~ .~ * Similar methods revealed the complex ion [CuP,O, en],- insolutions containing CU(II), pyrophosphate, and eth~lenediamine.~~Crystalline salts containing the anions AgX,-, PbX,-, and PbX42-[X = halogen] are reported to be formed from the appropriate halides andthe bisethyIenediaminecopper( 11) cation in the presence of sodium or ammon-ium chloride.The red Me,N*CH,*CH,*OH,CuCl, and yellow [Me,N*CH,*CH,( OH)],CuC14choline-copper( 11) complexes are unstable in water, but when prepared inethanol are better catalysts than copper sulphate or chloride for certainautoxidation rea~tions.~l Copper(r1) forms only a 1 : 1 complex withtriethanolamine, as shown both by spectrophotometry and transport-number experiment^.^,Tetramminocopper(rr) sulphate, Cu(NH,),SO,, has been used for the pre-paration of some copper(I1) complexes, e.g., with l-benzeneaz0-2-naphthoI.~~The dimer of cyclooctatetraene of m.p. 41.5" forms two compounds, withone and two mols. respectively of silver nitrate. Another dimer, m. p.38.5", forms a more stable 1 : 1 complex which appears to be one of the moststable silver-olefin compounds. 540" K.46These salts are unstable to boiling water.5043 R.Juza, H. H. Weber, and E. Meyer-Simon, 2. anorg. Chenz., 1953, 273, 48.44 W. D. Treadwell and W. Werner, Helv. Chinz. Acta, 1953, 36, 1436, 1445.45 J. By6 and J. Holder, Bull. SOL chim., 1953, 20, 399.46 H. N. Hersh, J . Anzer. Chew. Soc., 1953, 75, 1529.4 7 R. Vestin and C. Lofman, Acta Chenz. ScaNd., 1953, '7, 398, 745.48 J. I. Watters and A. Aaron, J . Amer. Chenz. SOC., 1953, 75, 611.49 J. I. Watters and E. D. Loughran, ibid., p. 4819.50 C. M. Harris and H. N. S. Schafer, J . Proc. Roy. SOC. N.S.W., 1952, 85, 148.51 P. L. White, D. M. Hegsted, and J. Meyer, J . AmeY. Chem. SOC., 1053, 75, 2352.52 J. M. Bolling and J. L. Hall, ibid., p. 3953.53 I.Kalugai, Bull. Research Council Israel, 1952, 1, No. 4, 96.54 Mi. 0. Jones, J., 1953, 2036COATES AND GLOCKLING. 93Contrary to previous claims, silver perchlorate has been shown not toact as a Friedel-Crafts type of catalyst. In those instances where there isapparent activity, it is due to the presence of free perchloric acid or to meta-thetical formation of an acyl per~hlorate.~~The relative formation constants of the silver complexes with a varietyof di-, tri-, and tetra-amines have been interpreted quantitatively on thebasis of only two collinear co-ordination positions on the silver ion. In veryfew instances was there evidence of further ~o-ordination.~~ The thiocyanategroup, however, seems to combine further, since formation constants havebeen reported for the ions Ag(SCN),-, Ag(SCN),=, and Ag(SCN),3-.57Group 11.-The heat of formation of beryllium oxide has been measuredagain by modern methods (AH,, = -143.1 & 0.1 k~al./mole).~~ Themonoclinic form of basic beryllium acetate, previously obtained by conden-sation from the vapour, can also be prepared by crystallisation from hottetralin.59The basic magnesium chlorides have been further studied,60 both bythermal decomposition of hydrated magnesium chloride and by crystallisationfrom solutions of magnesium oxide in concentrated magnesium chloride, thelatter depositing crystalline MgC1,,3Mg(OH),,8H20. A " Werner-complex "structure (11) was assigned to this salt, but the Reporters consider (111) tobe a more likely formula.The solutions of beryllia in aqueous berylliumsalts are probably similarly constituted.H H HH H H' O H j OH2(11) (111)About a third of the mzgnesium ions in the layer lattice of the compoundMg,((CH,) 9N,),(Fe(CN) 63,,24H20, which is easily prepared, may be exchangedwith a variety of small inorganic ions.61The heats of solution of calcium metal and calcium iodide in liquidammonia a t -33" have been measured; AH = -19-7 and -62.8 kcal.,respectively. For the reaction between calcium metal and the ammoniumion, AH = -99.3 kcal. From these data the value AH = -79.7 kcal. hasbeen calculated for the reaction2e-(NH,) + 2NH,+(NH,) = 2NH,(l.) + H2(g.)which agrees with the result obtained from the thermochemistry of thealkali metals in liquid ammonia, and indicates that calcium dissolves asCa++ ions rather than Ca+ or Ca2++ as had previously been suggested.Thestandard entropy of the calcium ion in liquid ammonia has also beenmeasured.625 5 13. Burton and P. F. G. Praill, J., 1953, 837.6 6 G. Schwarzenbach, Helv. Chim. A d a , 1953, 36, 23.5 7 G. C. B. Cave and D. N. Hume, J . Amev. Chem. SOC., 1953, 75, 2893.5 8 L. -4. Cosgrove and P. E. Snyder, ibid., p. 3102.59 H. D. Hardt and H. Hendus, 2. azorg. Chem., 1952, 270, 298.6 o G. Wehner, ibid., 1963, 272, 201.61 A. Weiss, A. Weiss, and U. Hofmann, ibid., 1953, 273, 129.62 S. P. Wolsky, E. J. Zdanuk, and L. V. Coulter, J . Amer. Chem. Soc., 1952, 74,618694 INORGANIC CHEMISTRY.A new structure has been proposed for the red peroxychromate of calcium,viz., Ca,Cr20,,,10H20.63As an example of the effect of lattice defects on colour it is noteworthythat red crystals of barium oxide up to 2 mm.x 1 cm., containing about0.1% excess of barium have been grown in a vacuum furnace atThe hydrazine complexes of zinc have been studied polarographically, 65and formation constants have been obtained for zinc-pyridine complexes.66Experiments on the dissociation equilibria of ammines of mercuricchloride and iodide, of similar pyridine complexes, and of " infusible whiteprecipitate " suggest the formula Hg0,HgC12,2NH, for the latter. Itwould seem to be formed by the partial hydrolysis (during preparation) of" fusible white precipitate," HgC1,,2NH,.67Solid solutions of the two mercuri-iodides Ag,HgI, and Cu,HgI,, whichchange colour on heating, have been prepared by simultaneous precipitation.The lattice parameters, colours, and colour-transition temperatures havebeen measured as a function of composition.68Group 1 I I .T h e structures of t e t r a b ~ r a n e , ~ ~ B,HIo, and the unstablepentaborane, 70 B5H,,, have been determined by improved and elaboratemethods. Of the higher hydrides of boron, only B 6 H I o remains of unknownstructure. All the hydrides examined, except diborane, offer valencydifficulties since they contain boron apparently bonded to five or six otheratoms.The dissociation of diborane to two molecules of boriute, BH,, probablyoccurs in many reactions of the former, but the presence even of a trace ofborine has never been detected in diborane.Thermodynamic calculationson the equilibrium B2H6 + 2BH3 indicate a degree of dissociation of 1.6 Xl.0-5 a t 155' and 1 atm., and under these conditions pyrolytic decomposi-tion is rapid. The heat of the reaction, AH2,30h: = -32 -J-- 4 kcal./mole ofdiborane, was estimated by comparing the heats of reaction of trimethyl-amine with B2H6, B,H2Me4, and BMe,. The entropy change (AS30,o~ =33.8 e.u.) was calculated from spectroscopic data and the known moleculardimensions of diborane, a planar structure being assumed for BH, and itsforce constants being estimated by Badger's rule. 71The order of the homogeneous vapour hydrolysis of diborane 72 is 312,first order with respect to water and 1/2 with respect to diborane; this isconsistent with the mechanism :B,H, 2BH,- +BH, + H,O -A H,B*OH, 4 BH,.OH + H,BH,*OH + H,O BH,(OH)*&H, __t BH(OH), + H,-BH(OH), + H,O BH(OH),~H, -+ B(OHJ, + H,63 J.B. Martinez and C. Porter, Anal. SOC. Quim., 1952, 48, B, 879 (Chem. Abs.,65 R. L. Rebertus, H. A. Laitinen, and J. C. Bailar, ibid., p. 3051; see also Ann.6 7 D. R. GIasson and S. J. Gregg, J.. 1953, 1493.68 L. Suchow and P. H. Keck, J . Amer. Chew. SOC., 1953, 75, 518.69 C. E. Nordman and W. N. Lipscomb, J . Chew. Phys., 1953, 21, 1856.70 L. R. Lavine and W. N. Lipscomb, ibid., p. 2087.71 S. H. Bauer, A. Shepp, and R. E. McCoy, J . Amer. Chent. SOC., 1953, '45, 1003. '* H. G. Weiss and I. Shapiro, ibid., p. 1221.1953, 47, 5837).Reports, 1952, 49, 95.64 G.G. Libowitz, J . Amer. Chern. SOC., 1953, 75, 1501.6 6 C. J. Nyman, J . Amer. Chern. SOC., 1953, 75, 3575COATES AND GLOCKLING. 95Diborane reacts with hydrazine or NN-dimethylhydrazine in ether at--80", giving white crystalline compounds BH3*6HR*&HR-BH, (R = Hor Me). Pyrolysis of the hydrazine compound gives a solid product, butthat of the dimethyl derivative gives a fairly volatile liquid, probablyBH,*NMe*NMe*BH,, apparently monomeric, which polymerises at aboutDiborane forms a co-ordination compound H,B-PHMe,, with dimethyl-phosphine ; this loses hydrogen at 150" forming mainly a trimer (Me,P*BH,),with some higher polymers. Similar compounds, e.g., (Me,P*BMe?!,, werealso prepared and ail are remarkable for their high thermal stability andchemical inertness, in contrast to most B-N compounds, e g ., (Me,N*BH,),.This difference is attributed to the use of 3d orbitals by phosphorus for P-Bbonding, an effect not possible with nitrogen.74Several co-ordination compounds between borine and trialkyl-phos-phines, -arsines, and -stibines have been prepared, and their reactions withhydrogen chloride studied ; in some instances borochlorides, containing theBC1,- ion, appear to be f0rmed.7~Although sodium borohydride has been known for some years and hasbeen, available commercially, descriptions of its preparation have onlyrecently appeared.76 Investigations at the University of Chicago into thepreparation of diborane, borohydrides, and similar substances since 1941have been summarised in one paper.'7 Experiments on the arc method forpreparing diborane from boron tribromide and hydrogen have shown thatdiborane can be purified from hydrogen bromide by reaction with a littlepyridine, and from other volatile impurities by conversion into the pyridine-borine complex followed by regeneration of diborane from the latter.'*Methyl borate reacts exothermically with sodium hydride : 79NaH + B(OMe), = Na[BH(OMe),]Sodium trimethoxyborohydride reduces carbon dioxide to sodium formate,Na[BH(OMe),] + CO, = H*CO,Na + B(OMe),, and its unstable aqueoussolution is a powerful reducing agent.Sodium hydride or lithium hydridereact with BF,,OEt, in two stages :600.73 - +LiH -+ Bl?,,OEt, = LiBHF, f OEt,3LiBHF, + GF,,OEt, = 4B,13, + 3LiBl7, + OEt,which provide a convenient method for the preparation of diborane.80 Thelatter may also be obtained by the reactionGNa[BH(OMe),] + 8BF,,OEt, = B,H, + GNaBF, + GB(OMe), + 80Et,Lithium hydride alone does not absorb diborane, but reaction is rapid inether suspension, with the formation of LiBH4,0Et276 (ether dissociationM. J.Steindler and H. I. Schlesinger, J . Amer. Chem. SOG., 1953, 75, 756.74 A. B. Burg and R. I. Wacner, ibid., p. 3872.75 F. Hewitt and A. K. Holyiday, J . , 1953, 530.76 G. Wittig and P. Hornberger, Annale?z, 1952, 577, 11; 2. Naturforsch., 1951,8, b, 225; H. I. Schlesinger, H. C. Brown, H. R. Hoekstra, and L. R. Rapp, J . Amer.Chem. SOG., 1953, 75, 199;. H. I. Schlesinger, H. C. Brown, and A. E.Finholt, ibid., p.205,r S H. I. Schlesinger, H. C. Brown, B. Abraham, N. Davidson, A. E. Finholt, R. A.Lad, J. Knight, and A. M. Schwartz, ibid., p. 191.70 H. C. Brown, H. I. Schlesinger, I. Sheft, and D. M. Ritter, ibid., p. 192.7 7 I d e m et al., ibid., p. 186.€1. I. Schlcsinger, 13. C. Brown, J. R. Gilbreath, and J . J . Katz, ibid., p. 10596 INORGANIC CHEMISTRY.pressure 10 mm. at 0'). Sodium hydride, however, does not react withdiborane, but sodium borohy dride is obtained from the trimethoxyboro-hydride by the very rapid reaction2Na[BH(OMe),] + B,H, = 2NaBH, + 2B(OMe),,or from sodium tetramethoxyborohydride :3NaB(OMe), + 2B,H, = 3NaBH, + 4B(OMe),Likewise potassium borohydride was prepared from KB (OMe),. Sodiumborohydride, stable to nearly 400" and in air to 300", dissolves in cold waterwith slight decomposition and can be crystallised as the hydrate NaBH,,ZH,Owhich can be dehydrated without loss of hydrogen.It is stable in the weaklyalkaline solution produced by its initial partial hydrolysis :NaBH, + 3H,O = NaH,BO, + 4H2but is rapidly decomposed by heat, acids, or transition-metal ions, notablyCo2+.S1 In contrast to lithium borohydride it is insoluble in ether anddioxan, but dissolves easily in ammonia, ethylenediamine, and the lowerprimary amines, isopropylamine being a convenient solvent for its extraction.Sodium borohydride reacts vigorously and quantitatively with BF,,OEt, :3NaBH, + 4BF,,OEt, = 2B2H, + 3NaBF, + 40Et,This reaction is a very convenient method for the preparation of smallquantities of diborane and is regarded as an example of the displacementof a weak acceptor (BH,) or " acid " by a stronger (BF3).76Sodium borohydride may be obtained without the use of diborane, themost satisfactory method being the reaction between sodium hydride andmethyl borate at 250-270" :4NaH + B(OMe), = NaBH, + 3NaOMeThe product is extracted with isopropylamine.Lithium borohydride canbe prepared similarly. Less satisfactory, but very interesting, methods arethe thermal disproportionation (- 230") of sodium trimethoxyborohydride,4Na[BH(OMe),] = NaBH, + 3NaB(OMe),the treatment of methyl borate and sodium with hydrogen under pressure4Na + 2H2 + B(OMe), = NaBH, + 3NaOMeand the remarkable solid reaction in which sodium hydride and boric oxideare ground together at 330-350''for 2 0 4 8 hours,4NaH + 2B,O, = NaBH, + 3NaB0,Aluminium borohydride is now most conveniently obtained from lithiumborohydride, which reacts more rapidly than the sodium salt , and aluminiumchloride : 82Beryllium borohydride is prepared similarly.Lithium borohydride isconveniently obtained from the sodium salt and lithium chloride in iso-propylamine solution, sodium chloride being insoluble in this solvent. A81 H. I. Schlesinger, H. C. Brown, A. E. Finholt, J. R. Gilbreath, H. R. Hoekstra,and E. K. Hyde, J . Amer. Chem. SOC. 1953, 75, 215.82 H. I. Schlesinger, H. C. Brown, and E. K. Hyde, ibid., p. 209.(2500) J3LiBH, + AICl, = Al(BH,),+ + 3LiCCOATES AND GLOCKLING. 97complex LiBH,-dioxan is more convenient to handle than LiBH, itself,being less hygroscopic.83 The storage of aluminium borohydride is danger-ous, not only on account of the spontaneous inflammability of its vapour,but also because of the slow generation of hydrogen and consequent pressureincrease. The decomposition is retarded by the accumulation of a reactionproduct of unknown constitution.82The preparation and properties of uranium(1v) borohydride 84 and someof its B-methyl derivatives s5 have been described in detail.The borazens, R,B*NR,, are of considerable interest since they are oftenmonomeric and appear to achieve co-ordination saturation by a substantialdegree of double bonding (R,B = NR,).The Raman spectra of Me3B*iH3,8s Me,B*NH, and Me,B*NMe, 87 giveB-N force constants appropriate to a single bond in Me3B-NH, and todouble bonds in the two borazens.The dipole moments of Me,B*NH,(4.15 0.06 D), Me36*&Me, (3-92 rJt 0.03 D), Me,B*NH, (1.47 & 0.06 D),and Me,B*NMe, (1.40 & 0.03 D) have now been measured. Corrected forB-C and N-H (or N-C) moments, the B-N bond moments are about 26-3 Din the borazan series and about zero in the borazens. The large moments tobe expected from the co-ordination formula- +-- +- -R,B - NR, and R,B = NR,are evidently reduced very considerably by unsymmetrical electron sharingin the sense B + N owing to the electronegativity difference betweenboron and nitrogen. Since double bonds are so much more polarisable thansingle bonds the effect is, as observed, greater in the borazen than in theborazan series.Useful experimental methods for the preparation of benzenesolutions of air-sensitive substances are also described. 88Specimens of boron carbide with formulz between B,C and B,C havebeen prepared and subjected to X-ray analysis. The hardness diminisheswith increasing boron content.89Co-ordination compounds between boron trifluoride and donor moleculescontaining oxygen have been the subject of some careful physical and electro-chemical studies.s0 Methanol being taken as a typical donor, the 1 : 1complexes are represented as- +2F,B*OHMe [MeOH,BF,]+[MeOBF,] -and the 1 : 2 complexes as [MeOH,]+[MeOBF,]-. Consideration of thereduced conductivity (molar conductivity X viscosity) of numerous borontrifluoride complexes, and comparison with various fused salts, indicatesthat the degree of self-dissociation is about 10% in complexes with water,alcohols, and acids, and 0.1% for esters, ethers, and tertiary amines.9183 R.Paul and N. Joseph, Bull. Soc. chim., 1953, 20, 758.8 4 H. I. Schlesinger and H. C. Brown, J . Amer. Chem. SOC., 1953, 75, 219.8 5 H. I. Schlesinger, H. C. Brown, L. Horvitz, A. C . Bond, L. D. Tuck, and A. 0.8 7 Idem, ibid., p. 133.8s R. D. Allen, J. Amer. Chew. SOC., 1953, 75, 3582.90 N. N. Greenwood and R. L. Martin, J., 1953,751,757.Walker, ibid., p. 222. 8 6 H. J. Becher and J. Goubeau, 2. anorg. Chem., 1952, 268, 1.88 H. J. Becher, ibid., 1952, 270, 273.'l Idem, ibid., p. 1427.REP.-VOL.L 98 INORGANIC CHEMISTRY.Pure lithium fluoroborate can be obtained from anhydrous Li,CO, andBF,,OEt, in dry ether.92The lowest chloride of boron, B4C14, has an electron-deficient structure.Each molecule consists of a very slightly irregular tetrahedron of boronatoms (mean B-B bond order Q ) , each boron being linked to a chlorineatom by a single bond.93 The '' dichloride " B,Cl, has an ethylene-likebut non-planar structure (symmetry V d ) .94 Boron trichloride and di-n-butyl sulphide form a stable 1 : 1 complex from which the sulphide can bedisplaced by ~ y r i d i n e . ~ ~Boron halides and alkylboron halides react readily with silicic acid andesters of the type R,LSi(OR')4-n, exchanging alkoxy-groups and halogenatoms,96 eg.,2R,SiOR' + BBr, = SR,SiBr + BrB(OR'),Several new boron sulphides have been prepared from boron halides andhydrogen sulphide.Excess of the latter gives metathioboric acidBX, + 213,s = SBSH + 3HXwhich has been obtained in di- and tri-meric forms (IV) andPH(IV) HS-B,S,B-SH HS-B /s-B\s\S-B(Excess of boron halide, on the other hand, gives halosulphides (BSX),,which disproportionate on standing : (BSX), __t BX, + B&98Evidence has been presented for the formation of phenyl radicals by thedecomposition of chloroform solutions of salts of the BPh,- anion; e.g.,diphenylmercury is formed when mercury is present. The ammoniumsalt NH,+BPh,- decomposes at 110-120" into benzene and iH,*BPh,.99The yellow addition compound between sodium and triphenylboron isdiamagnetic and believed to be Na2++ (Ph,B-BPh,)=.lOOEbullioscopic measurements show that aluminium hydride (from AlCl, +LiAlH,) is monomeric in ether, with which it is doubtless co-ordinated.The slow precipitation of an ether-insoluble polymer may be prevented byaddition of trimethylamine, which forms the more stable complexesAlH,,NMe, (m.p. 76") and AlH,(NMe,), (m. p. 95"). Both are monomericin ether and sufficiently volatile to be sublimed easily. The 1 : 2 compoundwould appear to be an example of a complex with the rare co-ordinationnumber five.lol92 I. Sliapiro and H. G. Weiss, J . Anzer. Chewz. SOC., 1953, 75, 1753.93 M. Atoji and W. N. Lipscomb, J . Chew. Phys., 1953, 21, 172.s4 M. J. Linevsky, E. R. Shull, D. E. Mann, and T.Wartik, J . Anzer. Chem. SOC.,06 E. Wiberg and U. Kriierke, 2. Naturforsch., 1953, 8, b, 608.9 7 E. Wiberg and W. Sturm, ibid., p. 530.99 G. A. Razuvaey and T. G. Brilkina, Doklady Akad. Nauk S.S.S.R., 1952, 85, 815.1953, 75, 3287. 95 M. F. Lappert, J.. 1953, 2784.98 Idem, ibid., p. 529.100 T. Li Chu, J . Amer. Chem. Soc., 1953, 75, 1730.lol E. Wiberg, H. Graf, and R. Us6n, 2. anorg. Chenz., 1953, 2'72, 221COATES AND GLOCKLING. 99Dimethylaluminium hydride has been prepared by a far more convenientmethod than the original gas-discharge process :(M = B, Al, or Ga). It is a very viscous, colourless liquid (v.P. 2 mm. at25"). The degree of association of the vapour varies between 2.5 and 2from 83" to 167", and the hydride is trimeric in isopentane solution at 2Oo.lo2The salts LiAlEt, and NaAlEt, have been prepared from Et3A1,0Et2and EtLi or EtNa.Aluminium ethylsulphinate (triethylsulphonylalumin-ium), Al(SO,Et),, results from Et3A1,0Et, and S0,.lo3A detailed study of the hydration and hydrolysis of aluminium bromideas vapour, solid, and combined with ether has shown that the primaryreaction involves hydration to Br3A1,0H2, which, if hydrolysis is avoided,is followed by formation of the octahedral complex Br,Al(H,O),. Furtherhydration then occurs by progressive replacement of the bromine atoms bywater molecules, giving finally [A1(H20]6)3+3Br- which is stable at roomtemperature and catalytically inactive. The results suggest that the pro-moter effect of aqueous halogen acids on aluminium halides in Friedel-Crafts reactions may be due to water rather than to hydrogen halide.lo4The preparation and manipulation of pure aluminium bromide has also beendescribed in connection with experiments on this compound as a solvent.Solvolytic reactions are discussed in terms of the ionisation equilibria : lo5LiAlH, + Me,M = Me,AlH + LiMMeH,AlBr, AlBr,+ + Br-AlBr, + Br- 'p- AlBr,-Conductivity studies on aluminium bromide and stannic chloride in thionylchloride solutions containing pyridine indicate the presence of the ions[py AlBr2]+, [pyz A1Br2]+, and [py SnC13]+.lo6The halogen-exchange reaction between HC1 and AlBr, goes as far asAlBrCl,, whereas HBr and AlCl, give A1Br3.107Aluminium chloride and bromide form complex salts with hydrazine, ofthe type (N2H5),A1X6,6H,O.It is suggested that AlCl,3- or AlBr63- ionsare present in these salts.lo8A study of the thermal decomposition of alumina trihydrate (Gibbsite)by X-ray and thermal analysis indicates two routes, one through the mono-hydrate (boehmite) and the other directly to the virtually anhydrous X-alumina.lo9 Data on the hydration of alumina have been reviewed andsupplemented.The reduction of anhydrous rare-earth chlorides with calcium is a satis-factory method for preparing the metals in most cases, but samarium andytterbium are reduced only to the bivalent state. Metallic samarium andytterbium have recently been obtained by distillation (from a tantalumcrucible) of a mixture of the oxide and lanthanum metal, since both metalsl o 2 T.Wartik and H. I. Schlesinger, J . Amer. Claem. SOL, 1953, 75, 835.E. B. Baker and H. H Sisler, ibid., p. 5193.lo* F. Fairbrother and W. C. Frith, J . , 1953, 2975.lo5 G. Jander and W. Zschaage, 2. anorg. Chem., 1953, 272, 53.lo6 L. E. D. Pease and W. F. Luder, J . Amer. Chewz. SOL, 1953, 75, 5195.lo' J. D. Corbett and N. W. Gregory, ibid., p. 5238.lo* W. Pugh and M. C. B. Hotz, J., 1953, 2493.109 J. F. Brown, D. Clark, and W. W. Elliott, ibid., p. 84.110 H. Ginsberg and M. Koster, 2. anorg. Chem., 1952, 271, 41100 INORGANIC CHEMISTRY.are considerably more volatile than lanthanum. Pure samarium meltsbetween 1025" and 1050", its density is 7.53, it is very soft and does notreadily tarnish in the air.lll Samarium metal can also be obtained fromthe anhydrous bromide and barium.112Techniques for the separation of rare-earth elements with the help ofethylenediaminetetra-acetic acid (" enta ") have been improved.lI3 Classicalmethods continue to be developed, e g . , for erbium salts,114 as well as thenewer processes. Gadolinium oxide in 95%. purity has been obtained on akilogram scale by countercurrent liquid-liquid extraction with tributylphosphate and nitric acid.l15Detailed optical data have been recorded for many hydrated rare-earthbromates,l16 and solubility and conductivity data for some rare-earth saltsin basic solvents ( e g . , morpholine) .l17 Thermodynamic data have beenobtained for the reversible hydrolysis of samarium( 111) and gadoliniumchlorides by water vapour,ll* and for the dissociati on of cerium(II1) sulphate1l9in aqueous solution, CeSO,+ S Ce3+ + SO,=.Cerium(II1) cyanamide, Ce2(CN2),, has been obtained from CeO,, NH,,and HCN at 600-880" ; the colour varies from yellow to dark green, perhapson account of lattice defects.120 Solutions of pure 12-molybdoceric(1v) acidhave been prepared by the use of an ion-exchange resin; the acid con-tains eight replaceable hydrogen ions, and the dimethylammonium salt(Me2NH),CeMo120,2,20H20 has been obtained.It is suggested that acentral CeO, octahedron is surrounded by MOO, octahedra.121Trimethylgallium forms unstable 1 : 1 co-ordination compounds withmethyl cyanide and acetone, but donor molecules con-taining reactive hydrogen give methane and dimerichie,Ga- - GaMe, products.Thus methanol gives (VI). The relativestability of these co-ordination compounds has beenMe (VI) investigated by reaction with trimethylamine ; whileMe/9\\6/(VI) does not react, the sulphur analogue is split reversibly :(Me,Ga.SMe), + 2NMe3 e- 2Me,Ga(SMe) -;Me,.A volatile acetylacetone complex, Me2Ga(C,H702), and a salicylaldehydederivative. Me,Ga*O*C,H,*CHO, have also been described. 122Raman spectra indicate that bath solid and liquid gallium(II1) chlorideare composed of Ga2CI, molecules with a bridge structure.l23The hydrolysis constant, K = [In0H++][HT]/[In3+], is 1.40 x 10-4 at25" from pH data.lZ4111 A. H. Daane, D. H. Dennison, and F. H. Spedding, J . Aulzer. Chem. Soc., 1953,113 E.J. Wheelwright and F. H. Spedding, ibid., p. 2529; J. K. Marsh, J . , 1952,115 B. Weaver, F. A. Kappelmann, and A. C. Topp, J . Amer. Chem. Sac., 1953, 75,1 1 7 T. Moeller and P. A. Zimmerman, J . Amer. Chem. SOC., 1953, 75, 3940.118 C. W. Koch and B. B. Cunningham, ibid., p. 796.119 T. W. Newton and G. M. Arcand, ibid., p. 2449.120 H. Hartmann and G. Dobek, Z . anorg. Chem., 1953, 271, 138.121 L. C. W. Baker, G. A. Gallagher, and T. P. McCutcheon, J . Anzer. Clzektz. Soc.,123 H. Gerding, H. G. Haring, and P. A. Renes, Rec. Trav. &him., 1953, 72, 78.124 L. G. Hepler and 2. 2. Hugus, J . Amer. Chem. Soc., 1953, 74, G115.75, 2272.4804.3943.112 E. I. Onstott, ibid., p. 5128.114 0. M. Hilal, 2. amrg. Chem., 1953, 278, 241.116 H.Schumann, Z. anorg. Chem., 1952, 271, 29.1953, 75, 2493. lZ2 G. E. Coates and R. G. Hayter, J., 1953, 2519COATES AND GLOCKLING. 101I n an investigation of the equilibrium In,O, + 3H, & 21n(l.) +3H,O(g.), leading to the thermodynamic constants of indium(II1) oxide,X-ray examination indicated absence of any oxide other than In,0,.125Solutions of indium(II1) chloride acquire reducing properties when shakenwith metallic indium and filtered. Quantitative investigation of this effecthas provided equilibrium constants for the formation of In+ and In2+ ionswhich can exist only at low concentration in solution.lZ6 The direct oxid-ation of thallous sulphide has been followed by X-ray diffraction, which hasshown that T1,O and T1,S,03 are the primary oxidation p r 0 d ~ c t s .l ~ ~From the variations of the thallous-thallic exchange rates with salt andacid concentration it seems likely, but not definitely proved, that the simpleTP+ ion participates in the reaction.lZ8Group 1V.-Measurements of the heat of sublimation of graphite, aquantity of great interest in connection with bond energies, have been com-plicated by uncertainties involving the accommodation coefficient forevaporation, and the identity and relative a mounts species. By using a mass spectrometer to identify atomic and molecularspecies, the heat of sublimation of graphite to 3P carbon atoms has beengiven the value 178.5 & 10 kcal./mole at 0" K,lZ9 a value which supports thehighest spectroscopic result of 170 kcal.Carbon atoms do not normally act as acceptors in the formation of co-ordination compounds.Since bonding to electronegative atoms enhancesacceptor properties, carbonyl chloride should be one of the most suitablecompounds to examine with the object of preparing a co-ordination compoundof carbon, and in fact a 1 : 1 complex is formed with trimethylamine : l 3 Oc1 Y1 +c1 c1O=C< + NMe, + OT-NMe,The complex decomposes about room temperature with evolution of methylchloride : 6CC12*6Me, _+ Me,N-COCl + MeC1.A highly reactive form of silicon has been prepared by the reactionSCaSi, + 2SbC1, - 6Si + 2Sb + 3CaC1,; with water it forms SiO, andhydrogen quantitatively in a few minutes. The silicon is considered toform a network of six-membered rings.131 Compounds of silicon withselenium and tellurium, having the composition SiSe, and SiTe,,132 have beenprepared from the elements at 1050" ; SiTe, crystallises in red plates with thecadmium iodide structure, and at 1200" forms the compound SiTe.TheSi-Te distance of 3.04 A in SiTe, corresponds more closely to metallic thanto ionic bonding.lS3Silica is noticeably attacked by hydrogen chloride in the presence of fusedalkali chlorides at lOOO", a reaction ascribed to the formation of unstable125 M.F. Stubbs, J. A. Schufle, and A. J. Thompson, J . Amer. Chenz. SOC., 1052,74,6201.126 L. G. Helper, 2. 2. Hugus, and W. M. Latimer, ibid., 1953, 75, 5652.12' B. Reuter and A. Goebel, 2. anorg. Chem., 1953, 271, 321.128 R. W. Dodson, J . Amer. Chem.Soc., 1953, 75, 1795.12Q W. A. Chupka and M. G. Inghram, J . Chem. Phys., 1953, 21, 371.130 J. Goubeau and G. Winkelmann, 2. anorg. Chem., 1953, 271, 235.131 H. Kautsky and L. Haase, 2. Nafurforsch., 1953, 8, b, 45.132 A. Weiss and A. Weiss, ibid., p. 104.133 Idem, 2. anorg. Chem., 1953, 273, 124102 INORGANIC CHEMISTRY.chl~rosilicates.~~~ A new method for the preparation of solutions of thevery unstable silicic acid has been devised, based on the reaction betweenpowdered hydrated sodium metasilicate and acid-treated cation-exchangeresin at 0". Silicate ions are probably monomeric in crystalline hydratedsodium metasilicate and in solutions of sodium orthosilicate.135 Startingfrom analcite (Na2O,A1,O3,4SiO2,2H2O), which is readily synthesised, anumber of other mineral silicates have been prepared by hydrothermalreactions.Several mineral-type silicates not found naturally have alsobeen prepared and ~haracterised.~,~Considerable interest has been shown in the chemistry of silicon halidesand related compounds. Partial hydrolysis of Si2C1, results in the formationof oxychlorides, of which (Si,C15)20 and Si2C1,*O*Si2C1,*O*SiC13 have beenis01ated.l~~ Ammonium halides and Si,C16 form polymeric nitrogen-con-taining compounds as well as SiCl, and SiHCl,, whilst trimethylammoniumchloride gives SiC1, and (SiCl,),. Both reactions are initiated by the freebase.138 Trichlorosilicon acetate, b. p. 130" (extrap.), has been preparedfrom SiC1, and anhydrous sodium acetate ; it readily disproportionates intoSiC1, and Si(OAc), with simultaneous formation of acetyl chloride andpolymeric products.139Ethylsilanes decompose at a measurable rate at 440-460" and are onlyslightly more resistant to decomposition than ~ i 1 a n e . l ~ ~ These reactions arecomplicated but are of interest in connection with the reaction between SiH,and olefins giving various alkylsilanes. 141 Hydrolysis of dimethoxydi-methylsilane by boiling water has led to the isolation of crystalline dimethyl-silanediol, Me,Si(OH),, m. p. 101" (decomp.). This compound, which maybe regarded as the parent body of the silicone polymers, can be kept withoutdecomposition only by cooling in liquid nitrogen; it condenses to a polymereven by the catalytic action of alkali from glass and is also very sensitiveto acids1,,The Raman spectrum of methoxytrichlorosilane, which is stable up to--500", has been r e ~ 0 r t e d . l ~ ~In view of the relative rarity of the co-ordination number five (see p. 98),a study of the SiF,-NMe, system is of some interest since it reveals compoundsSiF,,NMe, and SiF4(NMe3)2, both of which are almost wholly dissociated as~ a p 0 u r .l ~ ~Complex volatile silyl compounds, eg., P(SiH,),, P(SiH,),I, and P(SiH,)I,,result when SiH,I reacts with phosphorus or arsenic a t room temperatureand with antimony at higher temperatures. From the reaction betweenSiH,I and excess of sulphur the compounds SiH,-SH, (SiH,),S, and impurenon-volatile SiSI, have been is01ated.l~~ A number of substituted siloxenesSi603H,R, (R = EtNH, .C02Me, MeO, EtO) have been obtained through134 H. von Wartenberg, 2.anorg. Chem., 1953, 973, 257.135 G. B. Alexander, J . Amer. Chein. SOC., 1953, 75, 2887.136 R. M. Barrer, L. Hinds and E. A. White, J . , 1953, 1466.137 W. C. Schumb and R. A. Lefever, J . Amer. Chem. SOC., 1953, 75, 1513.138 C. J. Wilkins, J., 1953, 3409.139 J. Goubeau and R. Mundiel, 2. anorg. Chem., 1953, 272, 313.140 G. Fritz, ibid., 1953, 273, 275.142 S. W. Kantor, J . Amer. Chem. Soc., 1953, 75, 2712.14s J. Goubeau and H. Behr, 2. anorg. Chem., 1953, 272, 2.144 C. J. Wilkins and D. I<. Grant, J., 1953, 927.145 B. J. AyIett, H. J. Emeleus, and A. G Maddock, Research, 1953, 6, 303;.141 Idem, 2. Naturforsch., 1952, 7, b, 207, 507COATES AND GLOCKLING. 103the bromo-derivative (R = Br).The compounds are very sensitive toair and water and their preparation requires much experimental care.146The radical-exchange reactions between halides, isothiocyanates, cyanates,and phenylamino-derivatives of silicon, germanium, and phosphorus havebeen studied. 147 The alkylchlorosilanes give highly conducting solutionsin dimethylformamide, the dissociation constants being in the range 10-2 to10-4. The solutions undergo metathetical reactions. Some organo-germanium halides behave similarly. The MezSn2+ ion can be retained bycation-exchange resins, and elution with various acids has given a variety ofdime t h ylt in salts. l4The structural chemistry and reactions of the alkoxides of silicon, titanium,and zirconium have received further attention.A number of secondaryalkoxides of all three elements 149 and some alkoxyzirconium chlorides 150have been described. Zirconium alkoxides and acetyl chloride form mixedalkoxychlorides or addition compounds between the metal chloride and anester, e.g., Zr(OPri),,PriOH gave ZrC14,2Me*C02Pri.151 Theoretical aspectsof the whole series of alkoxides have been considered, including possiblestructures for the complex alkoxides in which titanium and zirconiumexhibit the co-ordination number 6. Vapour-pressure measurements ledto anomalously high entropies of vaporisation which were attributed to thepresence of complex molecules in the liquid, and a value of 18 kcal./molewas deduced for the energy of intermolecular attraction in [Zr(OEt),], and[Zr(OPri),],.The increase of entropy of vaporisation with chain lengthshown by normal alkoxides of titanium and silicon was explained in termsof “ entanglement ” of these molecules in the 1 i q ~ i d . l ~ ~ The alkoxides ofhafnium, Hf(OR), where R = Me, Et, Pri, Butt, and tert.-amyl, have alsobeen prepared and shown to resemble closely their zirconium analoguesalthough in certain cases the hafnium derivative was the more volatile.lmA preliminary communication has appeared on the preparation and pro-perties of germanium esters.154Alkyl titanates and lithium alkyls or aryls form complexes from whichthe alkyl(or ary1)titanium alkoxides maybe obtained, e g . , Ph,Ti(OR’),-, ;the stability increases with the electronegativity of R and decreases greatlyas n increases from 1 to 4.155Titanium tetrachloride and ammonia form amidochlorides at low tem-peratures, eg., Ti(NH2),C1, which decompose to TiNCl at 350°.156 Studieson complexes of Group IV elements are of particular interest in connectionwith the possibility of finding compounds in which a metal exhibits a co-ordination number of five.Titanium tetrachloride, unlike GeCl,, formsyellow complexes with a number of ethers; these are decomposed by heatto tarry products and are readily hydrolysed. Although TiC14,2Et20 isla6 H. Kautsky and H. P. Siebel, 2. anorg. Chem., 1953, 273, 113.147 H. H. Anderson, J . Amer. Chem. SOC., 1953, 75, 1576.148 K. Gingold, E. G. Rochow, D. Seyferth, A. C. Smith, and R.West, ibid., 1952,150 D. C. Bradley, F. M. Abd-el Halim, R. C. Mehrotra, and W. Wardlaw, J., 1952,152 D. C. Bradley, R. C. Mehrotra, J. D. Swanwick, and W. Wardlaw, J., 1953,2025.153 D. C. Bradley, R. C. Mehrotra, and W. Wardlaw, J., 1953, 1634.154 D. C. Bradley, L. Kay, and W. Wardlaw, Chem. and Ind., 1953, 746.155 D. F. Hermanand W. K. Nelson, .I. Amer. Chem. Soc., 1953, 75, 3877, 3882.156 G. W. A. Fowles and F. H. Pollard, J., 1953, 2588.74, 6306.4960.la9 D. C. Bradley, R. C . Mehrotra, and W. Wardlaw, J., 1952, 5020.151 Idem, J., 1952, 4609104 INORGANIC CHEMISTRY.monomeric in benzene, no molecular-weight data were obtained for the1 : 1 complexes such as that with anis01e.l~~An interesting example of solid solubility has been found ; when concen-trated hydrochloric acid is added to solutions containing ammonium ions,Ti(Iv), and Nb(v), mixed crystals of (NH,),TiCl, and (NH,),NbOCl, areformed.The latter salt, far more soluble than the former, cannot be pre-cipitated alone from aqueous s01ution.l~~Ammonium pentafluorozirconate(1v) and its monohydrate have beenobtained.Thorium hypophosphate, ThP,O,, which is useful for the separation ofthorium from rare-earth elements on account of its very low acid solubility,adsorbs both thorium and hypophosphate ions. Adsorption of thoriumions causes peptisation to clear solutions which can be dialysed and sedi-mented with an ultra-centrifuge.160Chelate complexes of Zr and Hf with a series of p-diketones,161 andthorium complexes of 8-hydroxyquinoline have been described. Someevidence is presented for the existence of [Th(~hthalate)~],- ions, and form-ation constants for the thorium complexes of a series of dibasic acids arequoted.163Germanium and its inorganic compounds have recently been reviewed.164isoPropylgermanium compounds of the types Pri3GeX (X = halogen, OH,NCS) and Pri,GeX, (X = halogen) have been prepared,165 and a series oftetra-alkoxygermanes, Ge(OR),. 166 A partial resolution of the trisoxalato-germanate(ru) ion through the quinine salt has been ~1aimed.l~'A convenient method for the preparation of dimethyltin dichloride bypassing methyl chloride through molten tin containing some copper has beenreported.168 Other salts of the dimethyltin ion 169 and hydrazine salts 170of fluoro- and bromo-stannates (SnX,),- and -stannites (SnX3)- have beendescribed.The lead oxide-bromide binary system is of interest in connection withthe formation of deposits in internal-combustion engines.An X-ray studyof this system confirms the existence of the four intermediate compoundsPhO,PbBr,, (PbO),PbBr,, (PbO),PbBr,, and (PbO) ,,PbBr, which hadearlier been detected by thermal a n a 1 ~ s i s . l ~ ~A variety of tri- and di-ethyl-lead compounds derived from mono- andpoly-basic acids have been prepared. Some metal complexes, e.g.,1 5 7 P. M. Hamilton, R. McBeth, W. Bekebrede, and H. H. Sisler, J . Avner. Chem. SOC.,1953, 75, 2881.J. Wernet, 2. anorg. Chem., 1953, 272, 279.H. M. Haendler and D. W. Robinson, J .A m e r . Chem. Soc., 1953, 75, 3846.160 T. Moeller and G. Q. Dawson, ibid., p. 3572.161 E. M. Larsen, G. Terry, and J. Leddy, ibid., p. 5107.162 T. Moeller and M. V. Ramaniah, ibid., p. 3946.163 M. Bobtelsky and I. Bar-Gadda, Bull. SOC. china., 1953, 20, 382.164 0. H. Johnson, Chem. Reviews, 1952, 51, 431.165 H. H. Anderson, J . Amer. Chem. SOC., 1953, 75, 814.166 0. H. Johnson and H. E. Fritz, ibid., p. 718.16' T. Moeller and N. C. Nielsen. ibid., p. 6106.168 E. G. Rochow and D. Seyferth, ibid., p. 2877; A. C. Smith and E. G. Rochow,169 E. G. Rochow, D. Seyferth, and A. C. Smith, ibid., p. 3099.1 7 l F. W. Lamb and L. M. Niebylski, J . Amer. Chem. SOC., 1953, 75, 511.i b i d . , p. 4103.W. Pugh, J., 1953, 1934, 2491.H. Gilman, S.M. Spatz, and M. J. Kolbezen, J . Org. Cham., 1953, 18, 1341COATES AND GLOCKLING. 105C0(NH3),C1,, react with chloroplumbic acid to give dark-coloured chloro-plumbates of the type [MA,]PbC1,,173 containing Pb(I1) and Pb(1v).Group V.-The remarkable blue compound regarded as " imine," NH,has now been obtained by passing hydrogen azide through an electric dis-charge at 0.01-0.1 mm. and condensing the effluent gas on a cold finger at-196". The blue deposit turns white at -125", giving ammonium azide.Neither ammonia nor hydrazine gave the blue compoundj but cyanic acidgave a purple deposit of similar ~r0perties.l~~The classification of oxidising agents as one- or two-electron-transferreagents, according to the nature of their reaction with hydrazine, has beenexamined in some The use of hydrazine containing 15N has shownthat for single-electron-transfer oxidation [e.g., Ce( ~ v ) , F~(III)] in acidsolution the N-N bonds are broken, while they remain intact, emerging asN,, in two-electron-transfer oxidations, e.g., V(v), and in all oxidations inalkaline s01utions.l~~A careful study of the water-ammonia system has revealed that ammon-ium oxide (NH,),O (m.p. -78.84") and hydroxide (m. p. -79.01") crystal-lise as pure compounds, and not as solid solutions in the eutectic regions.Accurate thermodynamic data were also 0btai11ed.l~~A spectrophotometric examination of the reaction between ammonia andchlorine in aqueous solution has confirmed and extended earlier work.Below pH 3 nitrogen trichloride is formed; at pH 3-5 dichloramine, andabove pH 8 monochloramine. In strongly alkaline solution chloramine ishydrolysed to h y p ~ c h l o r i t e .~ ~ ~An interesting series of salts containing the N,O,+ ion has been describedin a preliminary communication. Methods of formation include the actionof nitric oxide on nitrosyl aluminium chloride (NO+AlCl,-) in liquid sulphurdioxide or on nitrosylsulphuric acid, giving the so-called " blue acid,"N,O,+ HSO,;, and reduction of nitrosylsulphuric acid with sulphur dioxide,methanol, or formic acid.179Reactions involving dinitrogen tetroxide have received further study.Unstable addition compounds of the type N,0,,2B are formed with manytertiary arnines,lg0 while calcium and zinc oxides, and sodium peroxide andcarbonate give the metal nitrates.lsl Uranium and dinitrogen tetroxidecontaining an amine nitrate react with evolution of nitric oxide and formationof a trinitratouranyl complex, e.g., Et,NH[UO,(NO,)J.The reaction ratesincrease with dielectric constant in the absence of amine nitrate (e.g., additionof Et,N-NO), which suggests that reaction involves [NO+][NO,-] ion pairsfollowed by progressive oxidation of Unf ions : U __t Un+ -% U02+ %U022+.182 The conflicting data on the dipole moment of N,O, have beennNO+173 M. Mori, Bull. Chem. SOC. Japan, 1951, 24, 285 (Chem. Abs., 1953, 47, 3739).174 F. 0. Rice and M. Freamo, J . Amer. Chem. Soc., 1953, '75, 548; see also idern,175 W. C. E. Higginson, D. Sutton, and P. Wright, J ., 1953, 1380.176 W. C. E. Higginson and D. Sutton, J.. 1953, 1402.177 D. L. Hildenbrand and W. F. Giauque, J . Amer. Chem. Soc., 1953, 75, 2811.R. E. Corbett, W. S. Metcalf, and F. G. Soper, J . , 1953, 1927.17s F. Seel, B. Ficke, L. Riehl, and E. Volkl, 2. Naturforsch., 1953, 8, b, 607.180 D. A. Davenport, H. J. Burkhardt, and H. H. Sisler, J . Amer. Chem. Soc., 1953,181 C. C. Addison and J. Lewis, J . , 1953, 1319, 1874.182 C. C. Addison and N. Hodge, Nature, 1953, 171, 569.ibid., 1951, 73, 5529.75, 4175106 INORGANIC CHEMISTRY.reinterpreted by assuming that pN,O, is zero and that pNO, varies withtemperature. l*3The complicated thermal decomposition of calcium nitrite and hypo-nitrite has been studied.ls4When the vapour from white phosphorus is cooled from 600" on to a coldfinger at -196" only white phosphorus condenses.Cooling from lOOO",however, produces a dark brown deposit which changes irreversibly and a ta measurable rate between -100" and -50" into a mixture of white (80%)and red (20%) phosphorus. Brown phosphorus, assumed to be P,, isinsoluble in boiling propane or ethylene and in carbon disulphide at - 103" ;it is not appreciably paramagnetic. The formation of brown phosphorus ona cold finger held above red phosphorus at 350-360" is significant andsupports the view that P, molecules evaporate from heated red phosphorusand subsequently dimerise. lS5Greatly improved methods for the preparation of the three methyl-phosphines are described, involving successive methylation of phosphinewith methyl chloride in liquid ammonia containing the requisite quantityof sodium of barium.lS6Hypophosphoric acid is fully methylated by diazomethane ; the product,(MeO) 4P20,, is a monomeric, colourless, viscous 1iq~id.l~' Hydrolysis ofphosphorus tribromide by ice-cold aqueous bicarbonate gives the sodiumsalt of a new oxyacid of phosphorus, sodium diphosphite Na3HP,0,112H,0.Diphosphorous acid and its salts are oxidised to hypophosphoric acid (H,P,O,)by iodine and bicarbonate, and to pyrophosphoric acid by chlorine orbromine.lss There is some evidence] magneto-optic and cryoscopic, thatphosphorous acid is present largely as dimer, H6P20,, in non-aqueous solventsand concentrated aqueous solutions.lS9 Various esters of triphosphoricacid have been described.lgOA review of the metaphosphates and their behaviour on hydrolysis hasappeared.lgl Lead metaphosphate [Pb(PO,),].has been prepared byheating Pb(H,PO,), at 400°, and X-ray analysis indicates a long-chainpolymeric anion. Stirring a suspension with aqueous sodium sulphide givesa solution of sodium metaphosphate which, at 2% concentration, is about asviscous as glycerol, and gives a deep orange-red colour with silver salts.lg2Tertiary aromatic phosphine oxides add potassium to give " phosphyls,"ion radicals analogous to the ketylsPh,PO + K __t Ph,l?-O-K+These phosphyls are blue and paramagnetic in solution ; they can add anotherelectron, giving deep violet solutions containing Ph3P--O-)'K22+. Themagnetic properties of the latter are not reported.lS3Bond-energy data, mainly from heats of hydrolysis, suggest that the183 C.C. Addison and J. Lewis, J . , 1953, 1869.184 T. M. Oza and V. T. Oza, J., 1953, 907, 909.1135 F. 0. Rice, R. Potocki, and K. Gosselin, J . Auner. Chem. Soc., 1953, 75, 2003.186 R. I. Wagner and A. B. Burg, ibid., p. 3869.187 M. Baudler, 2. Naturforsch., 1953, 8, b , 326.188 B. Blaser, Bey., 1953, 86, 563.190 R. Ratz and L. Engelbrecht, 2. anorg. Chem., 1953, 272, 326; R. Ratz and E.392 K. R. Andress and K. Fischer, ibid., 1953, 273, 193.193 F. Hein, H. Plust, and H. Pohlemann, ibid., 1953, 272. 25,D. Voigt, Bull. Soc. chinz., 1953, 20, 517.Thilo, ibid., p- 333. 191 E. Thilo, G. Schulz, and E. M. Wichmann, ibid., p.182COATES AND GLOCKLING. 107P=O bond in the phosphorus oxyhalides resembles a double rather thana single (P+-0-) bond.lg4The low conductance of phosphorus pentachloride in phosphorus oxy-chloride, dioxan, ether, and nitrobenzene indicates that it is largely in acovalent form. In acetonitrile the conductance is much greater, andtransport measurements indicate the ionisation 2PC1, PCl,+ + PCl,-.lS5Conductometric titrations in POCl, solution have provided evidence forthe compounds : PCl,+SnCl,-, ( PCl,+),SnC162-, PCl,=TiCl,, PCl,+BCl,-,PC14+TeC1,- , and (PC1,+),TeC1,2-.1s6Hydrazine and related salts of antimony and bismuth halides lD7 and a1 : 1 addition compound of SbF, and dioxan lS8 have been obtained.Vanadium occurs in certain blood pigments and, in connection with these,a number of vanadium complexes have been investigated, mainly withethylenebissalicylaldimines, and their reduction-oxidation properties ex-amined.Some of these compounds behave in a similar manner to hmm-vanadium.lS9 The system Na,O-V,O,-H,O has been examined again, anda number of errors corrected.200Polarographic and spectrophotometric evidence for the existence of + 3and +4 oxidation states of niobium and tantalum in solution has beenobtained.201 A re-examination of the reaction between niobium penta-chloride and ammonia has led to the suggestion that impure niobium nitrideis produced through an intermediate NbC1,(NH2)2.202 Iodic and periodicacids form heteropoly-acids with niobium and tantalum.203Group V1.-The triple-point temperature (4.49" & 0-02') of tritium oxide,T,O, has been measured with use of only 0.15 C.C.(cf. D,O, 3-81').204The dehydration of several salt hydrates has been interpreted on thebasis of the formation of hydroxy-bridges, similar to those present in thep-diolcobalt ammines.205Two new allotropes of sulphur have been prepared.206 At 500-700"and between 0.1 and 1 mm. pressure, sulphur vapour consists mainly ofS, molecules ; if this vapour is allowed to impinge on a cold finger at - 196"a purple solid condenses. This has been named purple sulphur and itsparamagnetism 207 supports the suggestion that it consists of S, molecules.Purple sulphur is insoluble at -80" in propane, dimethyl ether, and toluene ;it is non-conducting and not volatile without decomposition.Even at-80" it slowly changes to yellow sulphur; the change is rapid at roomtemperature and a mixture of crystalline (40%) and amorphous (60%)sulphur is formed. Condensation at - 196" of the vapour from solid sulphurgives yellow rhombic sulphur, but condensation of vapour from liquid sulphurgives another allotrope, green sulphur. This probably consists mainly oflQ4 T. Charnley and H. A. Skinner, J., 1953, 450. lQ5 D. S. Payne, J., 1953, 1052.196 W. L. Groeneveld and A. P. Zuur, Rec. Trav. chim., 1953, 72, 617.lg7 W. Pugh, J., 1953, 1934, 3445.Ig8 H. M. Haendler, R. H. Glazier, and D. W. Breck, J . Amer. Chem. SOC., 1953, 75,lg9 H. J. Bielig and E. Bayer, Annalen, 1953, 580, 135.zoo H. Menzel and G.Miiller, 2. anorg. Chem.. 1953, 272, 81.201 R. E. Elson, J . Amer. Chem. Soc., 1953, 75, 4193.202 G. W. A. Fowles and F. H. Pollard, J., 1952, 4938.203 D. Sen and P. RAY, J . Indian Chem. SOC., 1953, 30, 250.204 W. M. Jones, J . Amer. Chem. SOC., 1952, 74. 6065.205 W. S. Castor and F. Basolo. ibid., 1953, 75, 4804, 4807.208 F. 0. Rice and C . Sparrow, ibid., p. 848; F. 0. Rice and J. Ditter, ibid., p. 6066.207 T. Freund, S. Adler, and C. Sparrow, J . Chem. Phys., 1953, 21, 180.3845108 INORGANIC CHEMISTRY.S, chains instead of S, rings; it reverts to yellow sulphur slowly at -100"and in a few seconds at room temperature.In a discussion on the allotropy of sulphur the strongly catalytic actionof sulphide ions and bases in accelerating the interconversion of allotropes isascribed to the opening of eight- or higher-membered rings with the form-ation, not of free radicals, but of normally constituted intermediates,20s e.g.,S' + (SJrhg 4 s--s---s-s-It is weakly para-magnetic.RaN + (S,)fins R,N+-S---S-S-The unbranched structure, OSSO, is preferred to S(S0,) for the dimerS,O, present in gaseous sulphur monoxide.209There have been substantial developments in the chemistry of thesulphur nitrides. The preparation of sulphurimide (S,NH) from S,Cl,and ammonia has been improved, and a 15% yield can now be obtained.Crystallised from methanol, it is colourless, m. p. 112.5", and it is monomericin benzene. With mercuric acetate an insoluble derivative Hg(NS,), isformed, but formaldehyde and alkali give colourless monomeric (in benzene)S,N*CH,*OH .210The sulphur hydronitride (HNS),, prepared by an improved methodfrom N,S,, reacts with mercuric acetate in pyridine with the formation ofa bright red colour followed by the deposition, in 97% yield, of green crystalsof Hg,(NS),.Excess of mercuric acetate, however, gives the yellow com-pound Hg(NS), in lower yield. A new oxysulphide of nitrogen, formulatedas (NS),SO, results from the reaction between Hg,(NS), and either thionylchloride ,or ethyl chlorosulphinate,Hg,(NS)* + 4sOcl2 = 4(NS),SO + 3HgC1, + Hg2Cl,Hg,(NS), + EtO*SOCl __t NS.SO*OEt __t (NS),SO + (EtO),SO(not isolated)The compound (NS),SO is an orange, mobile liquid, monomeric in benzene,and slowly decomposes even at 0" with the formation of N,S,.Alkalinehydrolysis gives ammonia :(NS),SO + 40H- + H,O = S,O,' + SO," + 2NH,The reaction between Hg,(NS), and sulphuryl chloride gives a dark blue,insoluble, probably polymeric, substance Hg,C1,(NS),.211A yellow crystalline substance, S3N202, m. p. 100-7", has been obtainedfrom ammonia and excess of thionyl chloride, and probably has the structure(VII, a, b, c). Monomeric in nitrobenzene, it is soluble in various organic208 H. Krebs and E. F. Weber, 2. anorg. Chem., 1953, 2'78, 288.210 A. Meuwsen and F. Schlossnagel, ibid., 1963, a71, 226211 A. Meuwsen and M. Losel, ibid., p. 217, 221.P. W. Schenk, ibid., 1952, 270, 301COATES AND GLOCKLING. 109solvents and can be sublimed.by alkali, giving trithionate :S3N20z f 4H20 = (NH4)zS306It is also formed, doubtless through S4N,)C1, when sulphur dioxide is bubbledinto a boiling solution of S,N, in thionyl chloride (S4N4 + 2S0,-Thiotrithiazyl chloride (S4N,Cl) liberates iodine from hydriodic acid, theThe structure (VIII, a, b, c)I t is hydrolysed by damp air, and rapidlySS3N2O2) .z12mean oxidation level of the sulphur being + 2 6+(VI I Ia)++ +-(VI I I b ) (VI I Ic)is suggested for the S4N,+ ion also by reactions with piperidine and withdilute ammonia vapour, the latter giving S,N,*NH3)C1.213The phase diagram for sulphamide-ammonia indicates formation ofS0,(NH,),,2NH3 and S0,(NH,),,3NH3.No 1 : 1 compound is formed.214The reaction between ammonia and sulphur trioxide in nitromethanesolution (in which SO, is monomeric) gives a mixture of ammonium tri-sulphate (NH4),S,0,,, and polymeric sulphimide (NHSO,),.The silversalt of the latter, with methyl iodide, gives not only the previously known(MeN-SO,),, but also (MeN*S0,)4.z15A further study of the reaction between sulphuryl chloride and ammoniasuggests that the ion NS0,- is an intermediate product. In the presenceof thionyl chloride, sulphanuric chloride (NSOCI),, m. p. 144-145", isobt aineda216Pyrosulphurylchlorofluoride, S205ClF, b. p. 100.1", is formed from S205C12 and silverfluoride, no S20,F2 being produced.217 The oxyfluoride S,O,F,, b. p. 120'(decomp.), is obtained as a heavy lower layer when BF, reacts with liquidSO, and concentrated sulphuric acid is added.Other methods are the thermaldecomposition of the compound I<BF,,4SO, and the reaction between KBF,and liquid SO, at - 70". The structure FS0,~O*S02*O*S0,F is suggested.218The reaction between sulphur trioxide and potassium fluoride has beenfurther examined. At room temperature a liquid is formed which depositscrystals of potassium fluorodisulphate, KS,O,F, on standing over concen-trated sulphuric acid in V ~ G U O . On heating, the salt loses a mole of sulphurtrioxide : 219Some new oxyhalides of sulphur have been prepared.K+[O,S.O*SO,Fj- --+ KS03F + SO,A Raman spectrum and phase-rule study of the sulphur trioxide-methane-sulphonic acid system has revealed the existence of a mixed anhydrideMe*SO,*O-SO,H ,2Me*S03H.220212 RI. Goehring and J.Heinke, 2. aNorg. Chem., 1953, 273, 297.213 M. Goehring and D. Schuster, ibid., 1953, 271, 281.214 H. H. Sisler and D. M. Rosenblum. .J. Amer. Chem. Soc., 1952, 74, 6130.215 R. Appel and M. Goehring, 2. apaorg. Chern., 1953, 271, 171.216 M. Goehring, J. Heinbe, H. Mak, and G. Roos, ibid., 1933, 273, 200.217 A. Engelbrecht, ibid., p. 269.2*8 H. A. Lehmann and L. Kolditz, ibid., 1953, 272, 73.219 Idem, ibid., p. 69. 220 I. Sandeman, J., 1953, 1135110 INORGANIC CHEMISTRY.Further work on sulphuric acid as an ionising solvent confirms that thefreezing point is maximum (10.36-10.37") and the electrical conductivityminimum (0.01033 ohm-l cm.-l at 25") at the composition H,S0,.221 Theconductivity, which is large for a pure liquid, is attributed to extensiveself-dissociation giving the ions H,O+, HS20,-, H,SO,+ , and HS0,- .222Transport-number measurements show that the last two ions have abnorm-ally high mobilities, of the order of 50-100 times those of other ions, anda chain mechanism involving proton transfer is suggested.223 The extent ofsolvation is K+ < Ag+ < Na' < Li+ < Ba++ < Sr++ , this order being confirmedby studies on the density and viscosity of solutions in sulphuric a ~ i d .2 ~ ~Conductivity measurements show that not only are the hydrogen sulphatesof the above ions strong electrolytes but so also are acetic, benzoic, andnitric acids, acetone, methanol, ethanol, triphenylcarbinol, rt-propylamine,aniline, o-phenylenediamine, hexamethylenetetramine, and dinitrogen tetr-oxide.Disulphuric acid, dichloroacetic acid, and p-nitrotoluene are weakelectrolytes, while sulphuryl chloride and trichloroacetic acid do not con-duct.225 The autoprotolysis of sulphuric acid has also been examined.2Z6By using H235S in the reaction,4so2 + 2H2S + 6NaOH = 3Na2S203 + 5H20it was established that all the central sulphur in the thiosulphate ion (Ex:)=originates from inactive SO,, while the exterior sulphur comes partly fromthe H2S and partly from the SO,.227A careful investigation of the sulphides of sodium, including preparationsfrom the elements in alcohol, toluene, and liquid ammonia, has shown thatNa,S,, Na,S,, and Na,S, may be obtained. A trisulphide, Na2S3, wasprepared in these ways but X-ray analysis has shown that it was not a singlesubstance, in contrast to the other polysulphides.The disulphide existsin two forms, and the pentasulphide is the highest stable polysulphide.228Numerous double sulphides, selenides, and tellurides, e.g., CuAlS,,CuGaSe,, and AgInTe,, have been made and generally found to crystallisewith the chalcopyrites (CuFeS,) stru~ture.2~~Selenium dithiocyanate, Se(NCS),, crystallises under suitable conditionsfrom an acidic solution of selenious acid to which a thiocyanate has beenadded. It is fairly stable at 5" if protected from moisture but suddenlydecomposes at 83-85' ; in dioxan or acetophenone it is monomeric.230Selenium tetrafluoride combines with mercury and with sulphur trioxide,forming HgSeF, and SeF,,SO,F,Tellurium dichloride has been prepared in good yield from CF,CI, and221 J. E.Kunzler and W. F. Giauque, J . Amer. Chem. Soc., 1952, 74, SO-1.222 K. J. Gillespie and s. Wasif, J . , 1953, 201.223 Idem, ibid., p. 209.225 Idem, ibid., p. 221.227 M. €3. Neyman, E. S. Torsueva, A. I. Fedoseeva, and P. S. Shantarovich, DoFzZady228 F. Feher and H. J. Berthold, 2. anorg. Chem., 1953, 273, 144.229 H. Hahn, G. Frank, W. Klingler, A. D. Meyer, and G. Storger, ibid., 1953, 271, 163.230 S. M. Ohlberg and I?. A. van der Meulen, J . Amer. Clzem. SOC., 1953, 75, 997.231 R. D. Peacock, J., 1953, 3617.224 Idem, ibid., p. 216.228 Idem, ibid., p. 964.Akad. Nauk S.S.S.R., 1952, 86, 317COATES AND GLOCKLING. 111molten tellurium ; it disproportionates rapidly in solution, into Te + TeC14.232Tellurium tetrafluoride forms an insoluble 1 : 1 co-ordination compoundwith pyridine ; the salt (pyH),TeF, was also prepared.233 The decafluoride,Te,F,,, is formed in yields up to 20% by the direct fluorination of telluriummixed with calcium fluoride.It is remarkably volatile (b. p. 54"; M ,Phase equilibrium data are given for the system Cr,(S0,)3-H,S04-H,0at 25" ; chromium does not form solid acid ~ u l p h a t e s . ~ ~ ~Several more addition compounds between chromium trioxide andpyridine bases have been prepared ; some, e g . , CrO,,a-picoline, are stableat room temperature. Chromium trioxide is monomeric in pyridine andboth cc- and p - p i ~ o l i n e . ~ ~ ~The oxidation of oxalic acid by potassium dichromate is well known to bean unsuitable reaction for volumetric purposes, and E.A. Werner 237 showedthat potassium dioxalatodiaquochromate(rII), IC[Cr(C,O,),(H,O),], wasfrequently formed in the reaction. The kinetics of the formation of thissalt from [Cr(H,0),l3+ ions and oxalate ions have now been studied polaro-graphically; the rate is limited by two consecutive slow reactions.238 Asolution of the complex contains, at equilibrium, much more of the cis- thanof the trans-isomer. The latter, however, crystallises when a solution isconcentrated sZowZy, since its solubility is so much less than that of the cis-isomer. The kinetics of the cis-tvans-isomerisation in this system havebeen studied spectrophotometrically at various temperatures, giving theheat, entropy, and free energy of isomerisati~n.~~~Improved preparations of chromium(m) ammines of the types [Cr en3]X3,[Cr en,Cl,]X, and [Cr,(OH),en,]X, have been described.240Some cis-diazidochromium(II1) complexes of the type [Cr en2(N3),]+ havebeen obtained from [Cr en3]C13 and NaN, in aqueous solution.241Thermal decomposition of tetraphenylchromium halides gives a mixtureof chromium carbide with reduced halides of chromium; the volatile pro-ducts contain much di~henyl.,,~The compounds Mo3Ge,, M02Ge3, a-MoGe,, and F-MoGe, have beenprepared, as well as the previously known M o , G ~ ., ~ ~Experiments using the 66-hour isotope sgMo have shown that the charge-transfer reaction between the Mo(CN),3- and Mo(CN),4- ions in aqueoussolution is extremely rapid.244The alkali fluorides interact with tungsten(v1) oxide in much the sameway as with molybdenum(vI)*oxide, and salts M3W03F3 and M3W04F havebeen prepared.245445) .234232 E.E. Aynsley, J., 1953, 3016.233 E. E. Aynsley and G. Hetherington, J., 1953, 2803.234 W. D. English and J. W. Dale, J., 1963, 2498.235 D. Taylor, J., 1953, 2502.236 H. H. Sisler, W. C. L. Ming, E. Metter, and 1'. R. Hurley, J. dnaer. Chenz. SOC.,238 R. E. Hamm and R. E. Davis, J . Anzer. Chem. SOC., 1953, 75, 3083.239 R. E. Hamm, ibid., p. 609.240 M. Linhard and M. Weigel, 2. aizorg. Chem., 1952, 271, 115.241 Idem, ibid., 1953, 271, 131.2J2 F. Heiii and H. Pauling, i t i d . , 1953, 273, 209.243 A. W. Searcy and R. J. Peavler, J . Amer. Claem.SOC., 1953, 75, 5657.244 R. L. Wolfgang, ibid., 1952, 74, 6144.245 0. Schmitz-Dumont, I. Bruns, and I. Heckinann, 2. morg. Clzem., 1953, 271, 347.1953, 7'5, 446. 237 E. A. Werner, J., 1888, 53, 602112 INORGANIC CHEMISTRY.Cryoscopic measurements in ice-sodium nitrate eutectic mixtures indi-cate that the main ion present in sodium peroxotungstate solutions isUranium and the Trans-uranic Elements.-Examination of the uranium-hydrogen system has been extended to a considerably wider range ofpressures and temperatures. The equation, log,, Pcm. = 5.78 - 1730/T, forthe dissociation pressure of UH, was obtained by observations between 500and 4900 cm. and 357-650", on compositions from UH,.,, to UH,.,. Thelimiting composition is UH,.,-,O.~~'The atmospheric oxidation of uranium dioxide at 120" has been followedby X-ray diff racti0n.2~~ Several investigations on mixed oxides containinguranium are reported.Uranium dioxide and magnesium oxide form solidsolutions only (no compounds) between 300" and 2350". The resultingfluorite structure with anion vacancies contains only a few moles yo of mag-nesia and has a great affinity for oxygen. The solid solubility of magnesiaincreases considerably as oxygen is taken up to near the limiting compositionThe relation between lattice constant and composition has been measuredfor the mixed oxides U,08-La20,, where La may be any of the lanthanonsLa, Pr, Nd, Sm, Yb, or Sc. The colours of these mixed oxides are brightand various, and in some cases there is opportunity for a random distributionof ions of different charge, e.g., Pr3+ and Pr4+.250 Cerium-uranium blue,CeUO,, has been prepared by ignition of the mixed hydrated oxidesprecipitated from Ce4+-U4+ salt solutions.The oxide has a fluorite lattice,and can be oxidised to CeUO,.,, by heating in oxygen. The electricalconductivity of the oxide is interesting in connection with the possibilityof electron exchange : 251 Ce4+ + U4+ + Ce3+ + U5+. The magneticsusceptibilities of UO,-ThO, solid solutions confirm the 6d2 configurationfor U ( IV) .2 52The inhibition by carefully dried potassium fluoride of the reactionbetween uranium hexafluoride and glass has greatly facilitated the measure-ment of a number of properties of this very reactive substance.Nickelresists attack even at 100" ; mercury is rapidly corroded at room temperature,but the reaction with dry Apiezon grease is so slow that greased taps maybeThe chlorination of U,O, with gaseous hydrogen chloride, previouslyattempted without success at lower temperatures, goes practically to com-pletion in three hours at 1200" ; the product is' U02C12.254Factors affecting the efficiency of the reduction or uranyl chloride toU(IV) chloride have been examined.255In attempts to prepare volatile compounds of uranium, complexes withthirteen 1 : 3-dicarbonyl compounds were prepared (some containing CF,246 K. F. Johr and 1LI. Blanke, 2. anovg. Chem., 1953, 272, 45.247 T. R. P. Gibb, J. J. McSharry, and H. W. Kruschwitz, J . Anzer. Chem.SOL, 1952,249 J. S. Anderson and K. D. B. Johnson, J., 1953, 1731.250 F. Hund and U. Peetz, 2. anorg. Chem., 1952, 271, 6.251 W. Riidorff and G. Valet, ibid., 1953, 271, 257.252 T. K. Dawson and M. W. Lister, J . , 1952, 5041.253 D. R. Llewellyn, J., 1953, 28.254 B. I. BoiiC and 0. Gal, 2. anorg. Chem., 1953, 273, 84.255 H. K. El-Shamy and S. El-Din Zayan, J., 1953, 384.[w203(0)2) 4, aq'l -'246uo,,~g0.24974, 6203. 24* P. Perio, Bull. Soc. chinz., 1953, 20, 256COATES AND GLOCKLING. 113groups). None of these, however, was as volatile as the borohydride ormet hylborohydride. 256X-Ray and chemical evidence suggests that f orbitals contribute tobonding in uranyl and plutonyl ions. Bonding byforbitals is only significantat small internuclear distances.257Further work on the disproportionation of pIutonium(1v) in acid solutionhas shown that a-particles from the plutonium seriously interfere withestablishment of equilibrium,2583Pu4+ + 6H20 e- 2Pu3+ + Pu02++ + 4H30+Suitable corrections have now been applied.The equilibrium constantdepends on the fourth power of the hydrogen-ion concentration; thissupports the existence of plutonyl ions P U O , + + . ~ ~ ~ The same is true for theequilibriumand thermodynamic data for both neptunium ions have been obtained.260The NpO,+ ion forms the complexes NpO,(C,O,)- and Np02(C20,),3-, whoseassociation constants have been measured.261 The neptunium compoundsNpC,, NpSi,, NpN, and Np,P, have been prepared, and their crystal formsstudied.262Group VI1.-Little work has been reported on inorganic fluorides ; thecompounds KMgF,, K,MgF,, and AgZnF, have been identified in the systemsKF-MgF, and A~F-ZIIF,,~~~ and a remarkable fluoride, NaCaCdYF,, whichhas the calcium fluoride structure.The metal ions, which are all about thesame size, are randomly distributed among the Ca++ positions.26* Con-venient preparative methods for the fluorinating agents, silver and antimonyfl~orides,2~~ and solubility determinations on a number of metal fluorides inBrF,,266 are reported.Valuable manipulative techniques involved in the preparation of sodiumfluoroacetate, labelled with 14C in the methylene group, have been de-~ e l o p e d . ~ ~ ' Direct fluorination methods under mild conditions by diffusionof reactants through nitrogen result in a very diffuse luminous flame in whichan average temperature as low as 48" can be maintained.This techniquehas been applied to the fluorination of carbon disulphide and has yieldedthe fully saturated derivative SF,*CF2*SF5 as well as SF,-CF,*SF,, CF,-SF,,CF,*SF,, CSF,, SF,, and S2F,,.268 A more satisfactory method is describedfor preparing the dangerously explosive compound trifluoroacetyl hypo-fluorite, CF,*CO,F (b. p. -21.5" & 1") by direct fluorination of CF3*C02H.2692 5 6 H. I. Schlesinger, H. C. Brown, J. J. Katz, S. Archer, and R. A. Lad, J . Anzev.Chewz. Soc., 1953, 75, 2446. 2 5 7 R. E. Connick and 2. 2. Huggs, ibid., 1952, 74, 6012.258 R. E. Connick and W. H. McVey, ibid., 1953, 75, 474.259 S.W. Rabindeau, ibid., p. 798.260 L. B. Magnusson and J. R. Huizenga, ibid., p. 2242.2 6 1 D. M. Gruen and J. J. Katz, ibid., p. 3772.262 I. Sheft and S. Fried, ibid., p. 1236.263 R. C. DeVries and R. Roy, ibid., p. 2479.264 F. Hund and K. Lieck, 2. anorg. Chenz., 1952, 271, 17.265 F. A. Anderson, B. Bak, and A. Hillebert, Acta Chem. Scand., 1953, 7, 236.266 I. Sheft, H. H. Hyman, and J. J. Katz, J . Amer. Chem. Soc., 1953, '95, 5221.267 €3. C. Saunders and T. S. Worthy, J., 1053, 1929.268 E. A. Tyczkowski and L. A. Bigelow, J . Amer. Chem. SOC., 1953, '95, 3523.269 G. H. Cady and K. B. Kellogg, ibid., p. 2501.Np4+ + Fe3+ + 6H,O Np02+ + Fe++ + 4H,O114 INORGANIC CHEMISTRY.Earlier work on the formation of cyanogen fluoride by the reaction AgF +ICN = AgI + FCN has been disproved, though some 3% of a producthaving mass 45 was found.270A convenient laboratory cell for electrolyses in anhydrous hydrogenfluoride has been used with dimethyl sulphide, which gave CF,*SF, (20%)and (CF,)2SF, (2%) in addition to much CF, and SF,.Carbon disulphideformed the compounds CF,*SF,, CF,(SF,),, CF,(SF,),, and free sulphur.Attempts to fluorinate the corresponding selenium compounds were un-su~cessful.~~1An improved method for the preparation of fluorocarbon iodides fromsilver salts of perfluoro-acids and iodine avoids the use of liquid solventsand d i l ~ e n t s . ~ ~ ~Studies on the reactions between trifluoroiodomethane and variouselements have been extended to phosphorus 273 and arsenic.274 The reactionsare believed to involve radical intermediates produced by homolytic fission,CF31 ___t CF,.+ I.With white phosphorus the compounds (CF,),P, (CF,),PI, CF,*PI,, P,I,,and PI, are formed (at 200-220"). Tristrifluoromethylphosphine, P(CF,),,b. p. 17.3", is spontaneously inflammable, but differs from its methyl analoguein not reacting with sulphur or carbon disulphide, nor does it co-ordinate tosilver or mercuric iodides. The monoiodo-compound (CF,),PT is particularlyinteresting since (CF,),P*P(CF,),, b. p. 84", is formed on reaction withmercury, and methyl analogues of neither of these are known.Trifluoromethylphosphines are readily hydrolysed by alkali, givingfluoroform, whereas alkyl- and aryl-phosphorus bonds are resistant tohydrolysis.Arsenic in a similar reaction with CF,I at 220" gives mainly tristrifluoro-methylarsine, (CF,),As, b.p 33", with small amounts of (CF,),AsT andCF,-AsI,. Tristrifluoromethylarsine, like (CF,),P, does not react withmercuric chloride, sulphur, or methyl iodide (in the dark). With gaseousmethyl iodide, ultra-violet irradiation causes an unusual exchange reactionto take place, with the formation of CH,As(CF,),, b. p. 52". The latter, too,does not co-ordinate to mercuric chloride. The halides (CF,),AsX andCF,*AsX,, best obtained from (CF,),As, are reduced by zinc and acid to thearsines (CF,),AsH and CF,-AsH,. Other compounds prepared include thefully fluorinated cacodyl, (CF,),As*As(CF,),. Like the sulphur and phos-phorus compounds, trifluoromethylarsines are sensitive to alkaline hydrolysis,with formation mainly of fluoroform.Bistrifluoromethylarsinous acid,(CF,),As*OH, obtained as the silver salt from (CF,),AsI and moist Ag,O,is very unstable, but the corresponding arsinic acid, (CF3),As0,H (hexa-fluorocacodylic acid), from (CF,),AsI and aqueous hydrogen peroxide, isstable. The electronic effect of the fluorine is well illustrated by the strengthof (CF,),AsO,H, comparable to that of hydrochloric acid (cf. cacodylic acid,270 H. J. Callomon, H. W. Thompson, F. A. Andersen, and B. Rak, J . , 1953, 3709.271 A. F. Clifford, H. K. El-Shamy, H. J. EmelCus, and R. N. Haszeldine, J., 1953,273 F. h i . Bennett, H. J. EmelCus, and R. N. Haszeldine, J . , 1953, 1565.274 G.R. -4. Brandt, H. J. EmelCus, and R. N. Haszeldine, J., 1952, 2552; H. J.Emel&s, R. N. Haszeldine, and E. G. Walaschewski, J., 1953, 1552; E. G. Wa!aschewslti,B e y . , 1953, 06, 272.2372. 2 5 2 G. H. Crawford and J. H. Simons, J . Anzer. Chem. SOC., 1953, 7'5, 5737COATES AND GLOCKLING. 115pK = 6.4); it would appear to be dibasic but in alkaline solution decom-position to fluoroform occurs.Iodine pentoxide dissolves in boiling iodine pent afluoride giving a colour-less solution which deposits iodine oxytrifluoride, IOF,, on cooling. Thelatter disproportionates on heating, ZOF, + I0,F + IF,, .giving a newoxyfluoride, iodyl fluoride, as a white solid, stable in dry air, but easilyhydrolysed to hydrofluoric and iodic acids. Solution in icdine pentafluorideregenerates IOF,.With the oxides P,O,,, V,O,, CrO,, and W03, iodinepentoxide gives POF,, VOF,, CrO,F,, and WO,,SIF,. Iodine pentafluorideabsorbs nitrogen dioxide giving a cream-coloured compound NO,,IF,, whichsublimes on gentle heating ; with potassium nitrate the iodohexafluorideKIF, results, and mercury gives the remarkable substance Hg(IF,),,apparently insoluble in water.275Anhydrous perchloric acid can be obtained from the 720/, acid and oleumby low-t emperature distillat ion. 76 Thermal decomposition of potassiumperchlorate is complicated : some chlorine as well as oxygen is producedin vacuo, but only oxygen when an inert gas is present. Some chlorate isalso f0rmed.2~7When a mixture of nitrogen, oxygen, and bromine is subjected to a low-pressure discharge a white solid is produced which is said to have the com-position (NO,),BrO, and to be volatile a t -40".The same substance isformed from bromine dioxide and nitrogen dioxide. Chlorine and iodinereact differently with nitrogen and oxygen, giving NOClO, and I,O,,respectively.278From the free energies of formation of complexes of halogens witharomatic compounds and of trihalide ions, the electron-acceptor orderICl > BrCl > IBr > I, > Br, > C1, is deduced.279 The solubility of iodinein aqueous sulphuric acid is a minimum at the composition H,0+HS04-.280It is well known that manganese heptoxide is formed from potassiumpermanganate and concentrated sulphuric acid, but the properties of thisdangerous compound have been studied only recently.I t has m. p. 5.9"and decomposes rapidly above 55". It is a non-conductor, having a di-electric constant of 3.28, and its shock sensitivity is similar to that of mercuryThe reduction of potassium permanganate is necessarilycomplex, and it is pointed out that manganese ions of valency intermediatebetween MnO,, and Mn0,- must be involved, thoGgh very little isknown about them. The reactions of various organic compounds withalkaline permanganate, insoluble barium manganate being used to removeMnO," ions as formed, have been studied and compared with manganicoxidations using manganese(rI1) pyrophcsphate.2s2A new apparatus for reduction by potassium in liquid ammonia withexclusion of air has been applied to the reduction of K,Mn(CN),.The paleyellow product, which is very sensitive to oxygen, has the composition275 E. E. Aynsley, R. Nichols, and P. L. Robinson, J., 1953, 633.2 7 6 G. F. Smith, J . Anzev. Chew. SOC., 1953, 75, 184.2 7 7 L. L. Bircumshaw and T. R. Phillips, J . , 1953, 703.278 A. Pflugmacher, 2. anorg. Chein., 1953, 273, 41.279 R. L. Scott, J . Amer. Chem. SOC., 1953, 75, 1550.280 J. G. Bower and R. L. Scott, ibid., p. 3583.281 0. Glemser and H. Schroder, 2. anoug. Chew., 1953, 271, 293.*E2 A. Y . Drummond and W. A. Waters, J . , 1953, 435116 INORGANIC. CHEMISTRY.K5Mn(CN),,K,Mn(CN),,2NH, and appears to contain both Mn(1) andMn(o) ; it is pararnagneti~.,~~Lithium rhenide (Li' Re-) has been prepared as a crystalline hydrate.284Electrolytic reduction of per-rhenates in concentrated sulphuric acidprovides some evidence for an unstable Re(v1) whilst reductionof per-rhenic acid with hydrogen iodide gave salts of Re(1v) and Re(v), e.g.,(NH4),Re16.286 The complex, cis-Re(py,Cl,), has been obtained frompyridine and (NH,),ReCl,, and the corresponding trans-isomer by the actionof hydrochloric acid an Re(py,C1,).287 Rhenium oxide and catechol oroxalic or gallic acid form complex acids,288 e.g., H[ (OH),Re(C,O,)H,O].Vapour-pressure and other thermal data have been obtained for two newsilicides of rhenium, Re,Si and ReSi, prepared by direct synthesis.Bothare thermodynamically unstable at 25" relative to ReSi,.zs9Group VII1.-The effect of pH on the rate of oxidation of ferrous hydr-oxide has an important bearing on the alkaline corrosion of iron. At a lowpH, y-Fe,O,,H,O is obtained ; in more alkaline solutions a-Fe,O,,H,O isformed when the oxidation is fast, and a material intermediate betweenFe,O, and y-Fe203 at low rates.290 The solubility product 291 and magneticsusceptibility 292 of ferrous hydroxide have been measured.Sublimation of ferric chloride in the absence of free chlorine gives aproduct containing small amounts of ferrous chloride in solid s0lution.2~~The formation of ferric chloride and calcium sulphate from ferric sulphateand calcium chloride is catalysed by both ferric chloride and traces of water,and is quite rapid above 300".294Work on the carbonitrides of iron and their reactions with ammonia andcarbon monoxide continues, and is of considerable interest in connectionwith industrial processes.295Basic nickel salts have been studied by precipitation at constant pH.296The preparation of pure nickel oxide has been examined in connection withexperiments onInterest in metal carbonyls and their derivatives continues, and manylaboratory preparations, which are greatly simplified by the use of dithionites(hydrosulphites) ,298 have been further improved by substituting formamidine-sulphinic acid for dithionite; e.g., the following reaction gives about an80% yield : 299 Ni2+ + (NH,),CSO, + 40H- + 4CO- Ni(CO), + SO,' +(NH,),CO + 2H20.75, 2495.283 V.J. Christensen, J. Kleinberg, and A. W. Davidson, J . Amer. Clzern. SOC., 1953,z84 A.v. Grosse, 2. Naturforsch., 1953, 8, b, 533 ; see also An?%. Reports, 1852, 49, 105.2 8 5 J. C. Hindman and P. Wehner, J . Amer. Chem. SOL, 1953, 75, 2869. 2873.286 B. Jezowska-Trzebiatowska, Trav. SOC. Sci. Lettres Wroclaw, 1953, B, 39, 5z 8 7 V. G. Tronev and S. M. Bondin, Doklady Akad. Nauk S.S.S.R., 1962, 86, 87.z 8 * D. Sen and P. RAY, J . Indian Chem. SOC., 1953, 30, 171, 181, 253.a89 A. W. Searcy and R. A. McNees, J . Amer. Chem. SOC., 1953, 75, 1578.z90 J. E. 0. Mayne, J . , 1953, 129.z91 D. L. Leussing and I. M. Kolthoff, J . Anzer. Chem. SOC., 1953, 75, 2476.2B2 J. Zernike, Rec. Trav. ckinz., 1953, 72, 390.2*3 H. Schafer and L. Bayer, 2. anorg. Chem., 1953, 272, 265.294 J. F. Hazel, W. M. McNabb, and W. D. Cooke, J . Amer.Chew&. SOC., 1953, 75, 1552.z95 W. K. Hall, W. E. Dietar, L. J. E. Hofer, and R. B. Anderson, ibid., p. 1442.z06 W. J. Singley and J. T. Carriel, ibid., p. 778. 297 G. Parravano, ibid., p. 1418.z98 E. 0. Fischer and W. Hieber, 2. ancwg. Chem., 1952, 269, 292, 305.299 Idem, ibid., 1953, 971, 229.(Chewt. Abs., 1953, 4'7, 9843)COATES AND GLOCKLING. 117Infra-red spectra and bond-length data for Ni(CO), and substitutedcarbonyls of the type (ligand),Ni(CO), indicate Ni-C double bonds andconsiderable double-bond character in the metal-ligand bonds.300 Theligands used were 2 : 2'-dipyridyl and o-phenylenebisdimet hylarsine.The dimeric cyanide of Ni(I), KqNi2(CN)6,301 absorbs carbon monoxidein solution, giving &[Ni(CN),CO] which reacts with acids according to theequation 302This reaction is strongly dependent on pH and follows the above equationonly at pH 7.This carbonyl cyanide and also K,[Ni(CN),(CO),] may beprepared, and isolated in pure form, by reactions in liquid ammonia.303The related iron compound has been prepared by the reaction 304Na,[Fe(CN),H,O] + CO ___t Na,[Fe(CN),CO] + II,OThe salt previously reported 305 as K,[Co(CN),CO] does not exist as such,but is a mixture of K3[Co(CN)J and K[Co(CO),]. Nickel carbonyl reactswith sulphur nitride in an inert solvent with precipitation of a black polymer :The latter slowly dissolves in several organic solvents, giving violet solutionsof the diamagnetic monomer, Ni(NS),.308Attention has been drawn to cobalt carbonyl hydride, Co(CO),H, whichis probably an active intermediate in reactions occurring in the presence ofcobalt catalysts between organic compounds and H,-CO mixtures at highpressures, since it gives very similar products to those obtained under actualhydroformylation conditions.307 It can be obtained pure and in high yieldby the action of pyridine on the readily available dicobalt octacarbonyl :Slow addition of this pyridine complex to dilute sulphuric acid liberatesCo(C0) *H.The proposed stabilisation of cobalt carbonyl hydride byhydrogen has been disproved, since there is no exchange with deuterium, andthe slow gas-phase decomposition is a second-order reaction. Althoughnot very soluble in water it behaves as a strong acid in titration with 0 . 1 ~ -sodium hydroxide.msThe reaction of dicobalt octacarbonyl with various bases has been studied.I t is remarkable that with dimethylamine a large proportion of the carbonmonoxide appears as dimethylformamide, and the rest according to theequationAt 220" and 200 atm.dimethylamine and piperidine are readily carbonylatedto the corresponding formamides, Me,N*CHO and C,H,,N*CHO, in thepresence of catalytic amounts of CO,(CO),.~O~4[Ni(CN),C0]2- + 2H,Of - Ni(CO), + 3Ni(CN),2- + H, + 2H20Ni(CO), + N,S,+ [Ni(NS),!, + 4CO12C5H5N + 3c02(co), __t ~ [ C O PY,][CO(CO),], + 8CO3Co,(CO), + 12Me2NH 2[Co(Me2NH),][Co(C0),1, + 8COR. S. Nyholm and L. N. Short, J . , 1953, 2670.301 R. Nast and W. Pfab, Naturwiss., 1952, 39, 300.302 R. Nast and T. von Krakkay, 2.anorg. Chem., 1953, 2'92, 233.,03 R. Nast and H. Roos, ibid., p. 242.304 W. Hieber, R. Nast, and C . Bartenstein, ibid., p. 32.305 W. Manchot and H. Gall, Ber., 1926, 59, 1056.a*5 M. Goehring and A. Debo, 2. anorg. Chem., 1953, 273, 319.307 I. Wender, H. W. Sternberg, and M. Orchin, 1. Arner. Chem. SOC., 1953, 15, 3041.ae* H. W. Sternberg, I. Wender, R. A. Friedel, and M. Orchin, ibid., p. 2717.309 Idem, ibid., p. 3148; W. Hieber, J. Sedlmeier, and W. Abeck, Ber., 1953, 86, 700118 INORGANIC CHEMISTRY.The anions Co(CO),- and Fe(CO),H- can be determined gravimetricallyas [Co phenan,] [Co(CO),], and [Fe phenan,] [Fe(CO),H]i which are insolublein ~ a t e r . 3 ~ ~Reactions in liquid ammonia have been used for the preparation of com-poundsof the types K,(NiR,), K,(NiR,), and K,(CuR,) in which R is an alkyneradical (-CiCH, -CiCMe, -CiCPh), e.g., [Ni(NH,)],(SCN), + 4PhCiCKK,[Ni(CICPh),]ZNH,. Loss of ammonia occurs in vacuo to giveK,[Ni(CiCPh),] as a yellow solid.This, with [Ni(NH,),](SCN), in liquidammonia, gives, on subsequent removal of ammonia, nickel(r1) phenylacetyl-ide Ni(CiCPh), as a black polymer. Potassium in liquid ammonia reducesK,[Ni(CiCPh),] to K,[Ni(CiCPh),], a compou'nd analogous to K,Ni(CN),.The reaction of cuprous iodide with potassium acetylide proceeds throughcuprous acetylide : 311CuCiCH + 2KCiCH __t K,[Cu(CiCH),]Important advances have been made in the study of metal biscyclo-pentadienyls, of which the orange-brown compound ferrocene " Fe(C,H,),was the first example.The red chromium,312 violet cobalt,313 and greennickel analogues have been obtained by an elegant method involvingreaction in liquid ammonia between an alkali-metal salt of cyclopent adieneand the appropriate metal ammine salt, followed by removal of ammoniain vacuo; e g . ,A striking feature of these compounds is their melting point, within a degreeof 173" in all cases. No doubt they are structurally very similar to the ironcompound, and, having practically identical exteriors, differ only in smallchanges in the atomic weight of the central atom, Cr, Fe, Co, Ni. Theyellow ruthenium compound Ru(C,H,),, reported last year, melts at 195.5" ;this rise in m. p. is likely to be due to ruthenium's being in a different periodfrom the former elements and differing substantially in atomic weight.Theiron compound is still the most stable.All the above compounds can be oxidised to singly charged cations,e.g., Ni(C,H,),+. Biscyclopentadienylnickel has also been obtained by theGrignard reaction : 315 C,H,MgBr + Ni(C,H,O,), _+c Ni(C,H,),, thoughthe corresponding reaction with the cobalt-acetylacetone complex orcobalt(I1) bromide leads to the cationic form Co(C,HJ2Br; the salt(Co(C,H,),) (BPh,) is quite insoluble. Stable biscyclopentadienyl-rhodiumand -iridium cations, analogous to Co(C,H.,),+, have been prepared. Thesalts are yellow and could not be reduced in aqueous media to the neutralcompounds.316 Titanium, zirconium, and vanadium tetrahalides react withcyclopentadienylmagnesium bromide to give cations of the type M(C,H,) ++.The titanium compound [Ti(C,H,),]Br, has been reduced to [Ti(C5H,),]Br.315These compounds are of considerable significance to chemistry, since they310 W.Hieber and H. Frankel, Bey., 1053, 86, 710.311 R. Nast, 2. Naturforsch., 1953, 8, b, 381.312 E. 0. Fischer and R. Jira, ibid., p. 1.314 E. 0. Fischer and W. Hafner, ibid., p. 444.318 G. Wilkinson, P. L. Pauson, J. M. Birmingham, and F. A. Cotton, J . Anzer. C]zem.316 G. Wilkinson, ibid., 1952, 74, 6148; F. A. Cotton, R. 0. Whipple, and G. Wilkin-[Ni(NH,),I(SCN), + 2KC5H, [Ni(NH3),I(C5H5), .__+ Ni(C,H,),a13 I d e m , ibid., pp. 217, 327.SOL, 1953, 75, 1011.son, ibid., 1953, '75, 3586COATES AND GLOCKLING. 119involve a quite unfamiliar type of covalent bonding, and like the higherboron hydrides and the metal-olefin compounds, can only be interpreted bymolecular-orbital methods (as opposed to the more readily visualised valency-bond treatment).It is no longer always possible to represent bonds inchemical formulze by drawing straight lines.Although aliphatic cc-di-imines are not known, their ferrous iodide com-plexes have been obtained in some instances, and provide an interestingexample of the stabilising effect of co-ordination.For example the crystalline salt (IX) has been isolated 1 ) from a mixture of ferrous iodide, diacetyl, and methyl-amine. The complex is hydrolysed by hot dilute acid,and both methylamine and diacetyl can be recovered (1x1almost quantitatively. The intense red colour of these compounds is similarto that of the well known 2 : 2'-dipyridyl complex, and it is suggested thatthe whole of the five-membered ring is conjugated by participation ofFe( 3 4 orbit als.,l7The equilibria involved in the formation of the FeSO,+ ion have beenmeasured a t 28" : 318/NMe=CH N(\NMe=CH 3[FeSO,+][Fe3+] [SO,-] = 95These results do not differ greatly from those calculated from kinetic dataon the oxidation of iodide by ferric ions in the presence of s ~ l p h a t e .3 ~ ~ Thereaction between potassium ferrocyanide and nitrosobenzene, in which theviolet ion [Fe(CN),,Ph*NOl3- is formed, is very strongly catalysed bymercuric ions even at ~O-'M.,~OFerrous-thioglycollic acid 321 and ferric-chloro-complexes have beenstudied; no FeC1,2- or FeClG3- ions are formed.322A series of cobaltammines [Co(NH,),(R-CO,)] (C104)2, where R rangesfrom CH, to C8H18, have been prepared by evaporating [Co(NH,),H,O] (ClO,),with R v C O , N ~ .~ ~ ~ The instability of iodopentamminocobalt (111) ions insolution is due to a reaction with iodide ions : 324Co(NH3),12+ + I- + Co(NH,),I+ + 1.Co(NH3),It + 6H,O __t CO(H,O),~+ + 5NH, + I-The heats of reaction of the successive replacement of H20 by Cl in the[CO(NH,),(H,O),]~+ and [Co en NH3(H20),-j3+ series of cations are much thesame, but entropy changes vary considerably.325Further examples of cobalt complexes with hexadentate ligands havebeen reported.326 The compound [Co tetren H20](C104)2, in which tetren istetraethylenepent amine, is paramagnetic, and evidently an ion-dipoleDoubt concerning the bonding in trisacetylacetonecobalt(II1)317 P.Krumholz, J . Amer. Chenz. SOC., 1853, 74, 2163.918 R. A. Whiteker and N. Davidson, ibid., p. 3081.320 S. ASperger, I. Murati, and 0. Cupahin, J., 1953, 1041.321 D. L. Leussing and I. M. Kolthoff, J . Amer. Chem. SOC., 1953, 75, 3904.922 G. A. Gamlen and D. 0. Jordan, J . , 1953, 1435.323 M. Linhard and B. Rau, 2. anorg. Chem., 1953, 271, 121.324 R. G. Yalman, J . Amer. Chem. SOC., 1953, 75, 1842.325 R. G. Yalman and (the late) A. B. Lamb, ibid., p. 1521.326 D. H. Busch and J. C. Bailar, ibid., p. 4574; F. P. D y e r , N. S. Gill, E. C.327 H. B. Jonassen and F. W. Frey, ibid., p. 1524.319 K. W. Sykes, J., 1952,124.Gyarfas, and F.Lions, ibid., pp. 1526, 2443120 INORGANIC CHEMISTRY.has been resolved by redetermining its magnetic moment.and is probably of the usual d2sp3 type complex.328[(ONO)Co(NH,),]X, __t [NO2Co(NH,),]X2 and related reactions variesgreatly with the anion for the solid compound, but not for the reaction indilute aqueous solution.329 The equilibrium between [CO(NH,),H,O]~+ and[Co(NH,) ,SO,]+ is almost independent of the sulphate-ion concentration ;this is ascribed to the presence of the former ion mainly as an ion-pairIt is diamagneticThe unimolecular velocity constant for the isomerisation[Co( NH,) 5H,0]3t*S042-.330Hvdrolysis of a series of C-substituted acetatopentamminocobalt (111)ions, ~R*CO,Co(NH,),]2+ with R = CH,, CH,CI, CCI,, CF,, 180 being used astracer, showed a gradual change in the position of bond fission from the C-0bond when R = CH, to the Co-0 bond with R = CF3.331Spectrophotometric examination of the chloro- and aquo-complexes ofCO(II) and Ni(I1) in octan-2-01 revealed the species CoCl+, CoCl,, CoCl,-,COC~,~-, and some evidence was obtained for the existence of an unstablecoloured chloro-complex ofThe influence of various agents, both complexing and non-complexing, onthe polarographic reduction of the hexamminocobaltic( 111) ion has beenexamined.333A study of the rate of aquation of trans-[Co(AA),Cl,]+ ions, in which thesteric properties of the bidentate group AA were varied, favours the S N 1dissociation mechanism involving a five-co-ordinated intermediate ratherthan the SN2 or displacement mechanism with a seven-co-ordinated inter-mediat e.334Compounds in which elements have the co-ordination number Jive areparticularly interesting since this number is uncommon, and two differentsteric arrangements of five bonds have been recognised.Recently, a numberof diamagnetic crystalline compounds of the type [Co( RoNC) ,]X have beenprepared in which R is an aryl group and X = I- or C10,-. These are1-1 electrolytes and the cobalt atom is no doubt isoelectronic with the ironin Fe(CO),, since carbonyl and isocyanide groups appear to combine withmetals in much the same way using essentially double bonds : compareNi(CO), and N~(RoNC),.~,~The species Ni(SCN)+, Ni(SCN),, and Ni(SCN),- have been identified innickel thiocyanate solutions in which the thiocyanate concentration ise 0 - 5 ~ ~ ~ ~ ~The Platinum Metals.-( 1) Ruthenium, osmium, rhodium, and iridium.Apyrosulphate of ruthenium, Ru(vI)O,S,O,, has been obtained from thetetroxide and sulphur trioxide.,,,328 R. 0. Whipple, R. West, and K. Emerson, J., 1953, 3715.329 B. Ardell, 2. anorg. Chem., 1952, 271, 49.330 H. Taube and F. A. Posey, J . Amer. Chem. Soc., 1953, 75, 1463.331 C. A. Bunton and D. R. Llewellyn, J . , 1953, 1692.332 W, D. Beaver, L. E. Trevorrow, W. E. Estill, P. C . Yates, and T. E. Moore, J .333 H. A. Laitinen and P. Kivalo, ibid., p. 2198; H. A. Laitinen, A. J. Frank, and334 R. G. Pearson, C. R. Boston, and F. Basolo, ibid., p. 3089.835 L. Malatesta and A.Sacco, 2. anorg. Chem., 1953, 273, 247.336 S. Fronaeus, Acta Chem. Scand., 1953, 7, 21.337 M. A. Hepworth and P. L. Robinson, J., 1953, 3330.Amer. Chem. SOC., 1953, 75, 4556.P. Kivalo, ibid., p. 2865COATES AND GLOCKLING. 121Several new co-ordination compounds of osmium have been prepared,eg., some penta- and hexa-ammino-osmium( 111) complexes,338 a para-magnetic Os(v) salt,33s and the thiourea complex ions [OS(III) (NH,°CS*NH2)6]3fand [OS(VI)O,(NH,*CS*NH,) 4] ++ .340An orange-yellow monomeric rhodium trisacetylacetone complex, m. p.260", subliming at 240" (1 mm.), and a yellow iridium analogue, m. p. 269",also volatile, have been obtained from Rh(m) nitrate and K,IrCl, respec-tively. These compounds deposit rhodium and iridium mirrors at 280-290°.341 Chemical or anodic oxidation of iridium(iI1) salts gives bluish-violet solutions containing the IrO*OH+ ion, and finally IrO,++. Reductionof the latter proceeds through an unstable form of Ir(rv), probably IrO++,Some cyclopentadienyl compounds of rhodium and iridium have beenmentioned earlier (p.1 18).(2) Palladium and $latinurn. Although platinum is well known to resistaqueous hydrochloric acid, attack occurs in the presence of those chlorides(e.g., KC1, CsC1) which form insoluble chloroplatinates, since the equilibrium-normally favourable to metallic platinum-is disturbed by separation ofthese salts. Gaseous hydrogen chloride also attacks platinum in the pres-ence of fused potassium chloride with the formation of K,PtCl,, whichdisproportionates to platinum and K,PtC1, onThe small number of cis-complexes of palladium has been extended bythe preparation of a series of cis-(SbR,),PdCl, compounds, advantage beingtaken of the low solubility of the highly polar cis-isomers in non-polarsolvents.cis-Isomers could not be prepared from phosphines and arsines,since the cis-trans-equilibrium lies very much in favour of the transformexcept when antimony is the donor.344 trans-Elimination reactions ofPdA,Cl, with sodium nitrite (A = aliphatic amine) are influenced by thesize and basicity of A.345More fluoropalladates 346 and fluoroplatinates 347 (M2PdF, and M,PtF,)have been described, as well as fluoroplatinic acid hydrate.3448Several palladium(I1) and platinum(I1) complexes with monoximes (e.g.,acetoxime) have been investigated.349 A hexamminoplatinum(1v) complex[Pt(NH,),](SO,), has been prepared by the action of ammonia and ammoniumsulphate on the methylamine compound [Pt (CH,*NH,),C1,]C1,.350 Theplatinum(1v) complex ion [Pt en2C1,I2+ has been partially resolved intooptical is0mers.3~~to 1ro.o~f.342338 F.P. Dwyer and J. W. Hogarth, J . Proc. Roy. Soc. N.S.W., 1950, 84, 117,33s Idem, J . Amer. Chenz. SOG., 1953, 75, 1008.340 R. D. Sauerbrunn and E. B. Sandell, ibid., p. 3554.341 F. P. D y e r and A. M. Sargeson, ibid., p. 984.342 F. P. Dwyer and E. C. Gyarfas, J . Proc. Roy. SOC. N.S.W., 1950, 84, 123.s43 H. von Wartenberg, 2. anorg. Chem., 1953, 273, 91.344 J. Chatt and R. G. Wilkins, J.. 1953, 70.345 H. B. Jonassen, T. 0. Sistrunk, J. R. Oliver, and G. F. Helfrich, J . Amer. Chem.347 T. P. Perros and C. R. Naeser, J . Amer. Chem. Soc., 1953, 75, 2516.348 R. S. Clarke and T. P. Perros, ibid., p. 5734.349 A. V. Babaeva and M. A. Mosyagina, Doklady A k a d . N a u k S.S.S.R., 1953, 89, 293;A. V. Babaeva and I. I. Lyuboshits, ibid., p. 681.350 K. I. Gil'dengershel, Zhur. Priklad. Khim., 1950, 23, 487.35L J. F. Heneghan and J. C . Bailar, J . Amer. Chem. SOL, 1953, 75, 1840.1952, 85, 113.SOC., 1953, 75, 5216. 346 A. G. Sharpe, J., 1953, 197122 I X 0 RG AN I C C €1 B M I STR I’ .The bridge bonds in the compound (PrT1,P),Pt,(SEt),C1, are sufficientlystable to have allowed the isolation of cis- (X) arid trans- (XI) forms, of whichE t(X) p = 1 0 . 3 ~4. Etthe cis-isomer is thermodynamically the more stable in benzene solution.This is also true for the bridged monothio-complex(Prn,P)ClPt(SEt)ClPtCl(PPrn,)The corresponding palladous complexes isomerise in benzene solution,though the cis-form predominates at eq~ilibriurn.~~z These results areparticularly interesting since it is the first time that cis- and trans-isomersof bridged complexes have been separately isolated ; normally only thctrams-form crystallises from solution.The long-standing uncertainty about the structure and bonding of theplatinum-olefin compounds appears now to be largely resolved.353 Theinfra-red spectra of several of these compounds, for which greatly improvedpreparative methods have been devised, indicate that the olefin retains itsdouble bond in the complex and is syininefricaEZy bonded to the platinum.This result, together with the observation that olefins behave as stronglytrans-directing ligands, suggests that the metal is bonded to the olefin byboth G and x bonds. The total (Pt-olefin) bond order is estimated at about4/3, and would seem to involve a G type of bond between a Pt(dse2) orbitaland the olefin bonding x orbital together with a x type of bond between#-Type bond @ ~ T y o t ? bonda Pt(dfi) orbital and the olefin antibonding X* orbital, the symmetries beingcorrect for these combinations.354 All of the properties of olefin complexescan be explained, at least qualitatively, in terms of this structure.355352 J. Chatt and F. A. Hart, J., 1953, 2363.353 J . Chatt and L. A. Duncanson, J., 1053, 2939.s54 M. J. S. Dewar, Bull. SOC. chim., 1951, 18, C79.955 J . Chatt, “ The General Chemistry of Olefin Complexes with Metallic Salts;Cationic Polymerisation and Related Complexes,” Heffer, Cambridge, 1053, p. 40COATES AND GLOCKLING. 123Some olefin complexes of platinum(I1) have been obtained in which oneolefin molecule appears to occupy two co-ordinationC ~ ~ ~ - C J & ~ > C ~ positions. The compound (XII), for example, isI monomeric in bromoform and its dipole moment, 6 D,c H z - c H ~ ~ H ) ~ ~ is consistent with the c i s - s t r ~ c t u r e . ~ ~ ~ A similar mono-meric and polar (p = 7 D) compound PtI,,C,H, wasprepared from cyclooctatetraene ; 357 two co-ordinatebonds a t right angles could readily be formed only from the " tub " form ofthe hydrocarbon, in confirmation of recent electron-diffraction data.358It would be expected from the picture of metal-olefin bonding reportedabove that substituted acetylenes would form complexes with platinouschloride. Attempts to prepare platinous complexes of dimethyl- anddiphenyl-acetylene gave some evidence of complex formation, but the com-pounds formed underwent rapid autoreduction to the metal and could notbe isolated.355The main product from the reaction between methylmagnesium iodideand platinum(1v) chloride is trimethylplatinum iodide, but Me,Pt, Me,Pt I,,MePtI,, and MePtI, have also been isolated from the complex reactionmixture. Tetramethylplatinum is obtained from Me,PtI and methyl-sodium, whereas metallic potassium affords hexamethyldiplatinum Me,Pt,,which is monomeric in benzene solution.359:Pt(XII)G. E. COATES.F. GLOCKLING.3513 K. A. Jensen, Acta Chem. Scand., 1953, 7, 866.357 Idem, p. 868.358 I. L. Karle, J . Chem. Phys., 1952, 20, 65.359 H. Gilman, M. Lichtenwalter, and R. A. Benkeser, J . Amer. Chem. SGG., 1953,75, 2063

ISSN:0365-6217    

DOI:10.1039/AR9535000089

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

ORGANIC CHEMISTRY.1. INTRODUCTION.A GREAT volume of work continues to appear and the task of Reporters is notmade easier by a growing tendency for authors to disclose researches in apreliminary way and subsequently to give a full account of the same work.Sometimes the results are so significant that notice must be taken of thepreliminary account but more sparing use of this form of publication would bewelcomed.The topics dealt with in the theoretical organic chemistry section of thisyear’s Report were last reviewed in 1951. In the intervening year thefocus of current interest seems to have centred mainly upon stereospecificfeatures of chemical change. This is significant in connection with theGrignard reaction, with elimination reactions of homocyclic compounds, andwith rearrangement reactions of saturated molecules.In the two years that have elapsed since stereochemistry was last reviewedmuch significant work has appeared, and the importance of modern ideasconcerning the conformations of cyclic compounds is evident in all recentwork on homocyclic compounds, including steroids, and also in carbohydratechemistry.Attention may be drawn to the recent agreement to refer to“ equatorial ” and “ axial ” bonds and to drop the overworked term “ polarbond ” from the vocabulary of stereochemistry. Prelog’s elegant applicationof McKenzie’s pioneer work brings a welcome refinement to the diagnosis ofstereochemical configuration, and Cram’s treatment of asymmetric inductionis simple in its appeal and convincing in its results.Further examples ofmolecular dissymmetry have been discovered, the most striking being thatof 9 : 10-dihydro-3 : 4-5 : 6-dibenzophenanthrene with its surprisingly highrotation and optical stability.Steady progress is being made in the study of unsaturated long-chaincompounds and a number of novel acids have been isolated from naturalsources. Considerable, though not spectacular, advances continue to berecorded in aromatic chemistry, experimental work providing quite a fewinstances in which the structural wave-mechanics theories fail to accountadequately for observed chemical reactivity. Many outstanding problems ofterpene chemistry are being rapidly solved. A prodigious amount of work ofuniformly high quality continues to appear on steroids; much of it centresstill around cortisone and the introduction of oxygen substituents into the11-position, but one may note in particular a new and strikingly simple totalsynthesis leading to ( &)-e+iandrusterone, in which six asymmetric centresare created stereospecifically in virtually one operation.The biogenesis of porphyrins has been considerably clarified during theyear and a chemical synthesis of sucrose has been announced. Perhaps themost outstanding accomplishment, however, has been the elucidation of thestructure and the synthesis of oxytocin, which will surely rank for manyyears as one of the greatest achievements in peptide chemistry.J.W.W. A. WWATERS AND DE LA MARE: THEORETICAL ORGANIC CHEMISTRY.1252. THEORETICAL ORGANIC CHEMISTRY.A noteworthy feature of the year under review has been the appearanceof a number of books which have greatly clarified modern viewpoints inregard to theoretical aspects of organic chemistry. Outstanding amongstthese is undoubtedly C. K. Ingold’s “ Structure and Mechanism in OrganicChemistry ” which gives a comprehensive, fully referenced survey ofmechanisms of heterolytic reactions in the terminology of the very activeresearch school of University College, London. Structural organic chemistryis also dealt with in J. M. Robertson’s “ Organic Crystals and Molecules ”which, like Ingold’s treatise, also has as its basis a series of G. F. Bakerlectures at Cornell University.Implications of the modern mathematical approach to organic chemistryhave been summarised by M.J. S. Dewar in a chapter in Volume I1 of theEnglish series “ Progress in Organic Chemistry.” Two further volumes of“ Organic Chemistry,” * the well-known advanced treatise edited by H.Gilman, have been published in the U.S.A. In these the American viewpointin regard to organic reaction mechanisms has been set forth by P. D. Bartlett,and there is a chapter on mechanisms of oxidation processes by W. A. Waters.A chapter by F. A. Miller on “Applications of Infra-red and Ultra-violetSpectra to Organic Chemistry ” also deserves mention since it meets the realneed of the experimentalist by providing a concise guide to the interpretationof modern spectroscopic measurements.Two books from the previous year are also significant : “Valence ” byC.A. Coulson is a non-mathematical account of applications of wave-mechanics to structural organic chemistry, whilst J. W. Baker’s “ Hyper-conjugation ’’ details critically the experimental evidence in support of thisparticular theory. The Comprehensive textbook written by E. E. Turner andM. M. Harris also contains far more discussion of theories than is usual,stereochemistry in particular receiving detailed treatment.Heterolytic reactions.The calculation,by molecular-orbital methods, of reactivities in the various possible positionsin aromatic systems continues to arouse interest.cf.8 Of theoretical importanceis the conclusion Sa that, when an unsaturated snbstituent such as vinyl,phenyl, or butadienyl orients substitution in the benzene nucleus, the o-should be more reactive than the p-position. That $-substitution is actuallyfavoured experimentally, as in the nitration of diphenyl, is attributed tosteric hindrance of o-substitution.The steric influence of the larger tert.-butyl group has been demonstrated by the analysis of the partial rate-factorsfor o-, m-, and f-nitration of toluene and terl.-butylbenzene.9 It is difficult,however, to estimate reliably the effect of smaller alkyl and vinyl groups on1. Aromatic Substitution.-(a) General considerations.1 G. Bell and Sons, London, 1953.3 Butterworths Scientific Publications, London, 1953.4 John Wiley and Sons Inc., New York, U.S.A., 1953.6, Clarendon Press, Oxford, 1952.7 “ Organic Chemistry,” Longmans.Green and Co., London, 1952.8 ( a ) M. J . S. Dewar, J . Amer. Chem. Sac., 1952, 74, 3341; ( b ) R. D. Brown, ibid.,(a) H. Cohn, E. D. Hughes, M. H. Jones, and M. Peeling, Nature, 1952, 169, 291;Cornell Univ. Press, U.S.A., 1953.1953, 75, 4077.( b ) K. L. Nelson and H. C. Brown, J . Amer. Chem. Soc., 1951, 73, 5605126 ORGANIC CHEMISTRY.the rate of o-nitration. If R. D. Brown’s conclusion 8b is correct, then sterichindrance of o-substitution must in general be considerably larger than hashitherto been thought. On the other hand, a considerable body of opinionfavours the view that the quinonoid transition state for $-substitution will beenergetically more favourable than that for o-substitution. Thus W.A.Waters lo stresses the .analogy that P-quinones have a smaller energy contentthan o-quinones, and C. K. Ingold 1y p. 267 gives a qualitative quantum-mechanical justification for this view, concerning which there seems, there-fore, to be divergence of opinion.With regard to the nature of the intermediates involved in aromaticsubstitution, there have been a number of papers,ll dealing with the spectraof the complexes, ArH,X,, between aromatic substances and halogens.H. C. Brown and his co-workers l2 have studied the complexes formed byvarious alkylbenzenes with ( a ) hydrogen chloride and (b) aluminium chloride.Differences in the effects of structure of the aromatic compound on thestabilities of these complexes led these workers to conclude that two types areinvolved, namely, “ n-complexes,” in which the ring as a whole acts as a base,and “ o-complexes,” in which the “ acid ” is attached specifically to one ofthe aromatic carbon atoms.Analogies between the effects of structuralchanges on complex formation with aluminium chloride and on the rate ofaromatic substitution suggested that the latter type of reaction involvesG- rather than ~ i - complexes.G. Williams and his co-workers l3 showed that the changein rate of nitration of, e.g., the trimethylphenylamrnoniurn ion with solventcomposition in the range 82-90% sulphuric acid follows the extent ofionisation of 4 : 4’ : 4”-trinitrotriphenylmethanol in the same range ofmedia. Since such alcohols ionise according to the equation ROH +2H,SO,+ R+ + H,O+ + 2HS0,- (thus giving a measure of the J.acidity function),14 this result is taken as implying that nitration under theseconditions involves the nitronium ion, formed by the similar reaction :NO,*OH + 2H,S04 += NO,+ + H30f + 2HS04-.These workers haveshown that pentadeuteronitrobenzene is nitrated, in strong sulphuric acid, atthe same rate as nitrobenzene, thus confirming Melander’s conclusion l5 thatthe loss of a proton is not part of the process controlling the rate of nitration.A similar conclusion has been reached l6 from measurements of the rate ofnitration of monodeuteronitrobenzene; it can be taken that, contrary to aprevious Report,l7 a base is not kinetically required for nitration even of therelatively unreact ive subst rates.128 ORGANIC CHEMISTRY.methylaniline itself reacts with bromine much too rapidly for convenientmeasurement.A contribution has been made27 to the problem of the unexpected0, $-halogenation caused by the nitroso-group. I t has been shown that it isvery difficult to obtain a direct reaction of nitrosobenzene with bromine ;at first, substitution is extremely slow, but it becomes autocatalysed by theproduction of traces of hydrogen bromide.This, it is suggested, adds to thenitroso-group, thus producing intermediates, such as Ph*NBr*OH, which canparticipate in complex condensation and substitution reactions.Various workers 28 have studied the reactions of acidified hypochlorousacid with aromatic substances. With unreactive substrates, the kineticform is -d[ClOH]/dt = K[ArH][ClOH][H+] ; this result is consistent with theintervention of ClOH,+ or of C1’ in the reaction..With more reactive sub-stances, such as methyl p-tolyl ether, the rate of reaction, provided thatchloride ions are removed by added silver salts, may become of the form-d[ClOH]/dt = K[ClOH] + K’[ClOH][H+]. It is considered 28a that sincethe reaction velocity is independent of the concentration of aromatic com-pound the slow heterolysis of ClOH and C10H2+, giving Cl’, is being measured.With still more reactive aromatic compounds, such as phenol, the kineticequation becomes of the form :-d[ClOH]/dt = R[ClOH] + R’[ClOH][H+] + K”[CIOH][ArH][H+] . . ( 1 )The appearance, with very reactive aromatic compounds, of the last term inequation (l), taken in conjunction with the observation of a similar kineticterm with very unreactive substrates, is considered to be evidence that thesecond term in equation (l), observed with compounds of intermediatereactivity, does not represent the rate of a slow proton transfer to oxygen.Since added ions, X-, often powerfully catalyse chlorinations by ClOH, itis presumed that compounds C1X are in such cases the effective electrophilicreagents. Halogen acetates and related substances have been used pre-paratively,Z9 and further kinetic evidence for the existence and electrophilicbehaviour of chlorine acetate has recently been given.30The displacement reactions of arylboronic acids have been examinedkinetically : 31This reaction appears, from the effect of change in R on the rate, to involve anelectrophilic displacement by bromine on the aromatic system.Admirable summariesetc etc.Alicyclic compounds.Small and Large Rings.-Syntheses of n- and iso-propylcyclopropane,methylenecyclopropane,2 and nitrocyclopropane 3 have been described. Thelast, which was characterised by reduction to cyclopropylamine, does notform salts in strong alkaline media at 25°.3 The synthetic route to vinyl-cyclopropane derivatives has been extended by the condensation of 1 : 4-dibromobut-2-ene with ethyl cyano- and aceto-acetateJ5 and of 1 : 4-di-bromocyclopent-2-ene with ethyl malonateP6 the latter reaction giving abicyclo[3 : 1 : Olhexene derivative (I).Alkylated cyclopropanes can beprepared by the action of zinc on the addition products of hydrogen bromidet o a number of diene hydrocarbon^.^CH CMe(1) (11) (111)The adduct of phenylacetylene with 1 : l-dichloro-2 : 2-difluoroethyleneis the cyclobutene (II).8 This can be converted into derivatives of cyclo-butenone, cyclobutanone, and cyclobutane. Sulphuryl chloride and dimethyl-acetylene give the cyclobutene (III).g cis- and trans-l-Ethyl-3-methylcyclo-butane have been described.1° The heat capacities of solid and liquid cyclo-butane have been determined.lla-Carboxy- and a-cyano-adipic acid yield cyclopent anones when heatedwith hydrobromic acid.l2 The reaction is largely specific for the formationof a five-membered ring.The acyloin condensation leading to five- and95 F.A. Hochstein, C. R. Stephens, L. H. Conover, P. P. Regna, R. Pasternack,P. N. Gordon, F. J. Pilgrim, K. J. Brunings, and R. B. Woodward, J . Amer. Chem. SOC.,1953, 75, 5455.1 H. Pines, W. D. Huntsman, and V. N. Ipatieff, J . Amer. Chem. SOC., 1953, 75, 2311.J. T. Gragson, K. W. Greenlee, J. M. Derfer, and C. E. Boord, ibid., p. 3344.H. B. Hass and H. Shechter, ibid., p. 1382.R. W. Kierstead, R. P. Linstead, and B. C. L. Weedon, J., 1952, 3610.Idem, J., 1953, 1799.R. Ya. Levina and B. M. Gladshtein, Zhur. Obshchey Khim., 1952, 22, 585.* Idem, ibid., p . 1803.* J. D. Roberts, G. B. Kline, and H. E. Simmons, jun., J . Amer. Chem. SOC., 1953, 75,0 I. V. Smirnov-Zamkov, Doklady A k a d . N a u k S.S.S.R., 1952, 83, 869.lo B.A. Kazanskii and M. Yu. Lukina, Izvest. A k a d . N a u k S.S.S.R., Otdel. Khim.11 G. W. Rathjens, jun., and W. D. Gwinn, J . Amer. Chem. SOC., 1953, 75, 5629.l2 L. Crombie, J. E. H. Hancock, and R. P. Linstead, J., 1953, 3497.4765.N a u k , 1952, 314202 ORGANIC CHEMISTRY.six-membered rings is carried out effectively with sodium in liquid ammonia.13The two isomers of 1 : 3-dimethylcyclopentane have in the past had the wrongconfiguration ascribed to them, the lower-boiling isomer being, in fact,The preparation has been described of some cyclohexane-1 : 3-diones andtheir enol ethers,16 and their ultra-violet absorption spectra have beenreported.l7 An extension to various enolised a- and P-diketones of Wood-ward’s empirical rules for the calculation of A,,,.has been discussed.l71 : 2-Dimethylenecyclohexene l8 and 4-methyl-3-vinylcycZohex-3-enol l9have been prepared. The latter does not undergo the Diels-Alderreaction.19~20In recent years it has been realised that the properties of a substituenton a cyclohexane ring are profoundly influenced by its conformation. Therelation between conformation and reactivity has been well summarised byBarton.21 In the chair conformation of cyclohexane there are two types ofgeometrically distinct carbon-hydrogen bonds. Six of these bonds lieparallel to the three-fold axis of symmetry and until recently they havebeen designated “ polar.” It has now been proposed that the term “ axial ’’replace “ polar.” 22 The remaining six carbon-hydrogen bonds are stilltermed “ equatorial.”Conformational analysis indicates that cis-1 : 3-disubstituted cyclo-hexanes should be more stable than the corresponding tmns-isomers sincethe two substituents in the cis-arrangement can both be equatorial.Thegreater stability of the cis-isomer has been shown in the cases of the 3-methyl-~yclohexylamines,~~ 3-bromo- 24 and 3-hydroxy-cycZohexanecarboxylic acids,253-methyl~ycZohexanols,~~-~~ 3-methylcycLohe~ylmethanols,~~~ 29 and 1 : 3-bis-hydroxymethyl- 30 and 1 : 3-dimethyl-cy~Zohexanes,~~~ 31 and in some casesthe original stereochemical assignment has been reversed. The cis- andtrans-1 : 2- 32 and -1 : Pbishydroxymethyl-cy~lohexanes,~~ 1 : 2- and 1 : 4di-methylcy~lohexanes,~~ and 2- and 4-methylcycZohexylmethanols 34 have beendescribed.The most stable conformation of 2-bromo- and 2-chloro-cyclohexanone isthe chair form with the halogen atom axial, but that of 2-bromo-4 : Pdi-~is.14~15l 3 J.C. Sheehan and R. C . Coderre, J . Amer. Chem. SOC., 1953, 75, 3997.l4 S. F. Birch and R. A. Dean, J., 1953, 2477.l5 J. N. Haresnape, Chem. and Ind., 1953, 1091.l6 E. G. Meek, J. H. Turnbull, and W. Wilson, J., 1953, 811.l 7 Idem, ibid., p. 2891.lo G. Stork, S. S. Wagle, and P. C. Mukharji, ibid., p. 3197.2o Cf. P. A. Robins and J. Walker, J., 1952, 1610.21 D. H. R. Barton, J., 1953, 1027.22 D. H. R. Barton, 0. Hassel, K. S. Pitzer, and V. Prelog, Nature, 1953, 172, 1096.23 D. S. Noyce and J. R. Nagle, J . Amer. Chem. SOL, 1953, 75, 127.25 S. Siegel and J.G. Morse, ibid., p. 3857.25 S. Siegel, ibid., p. 1317.26 D. S. Noyce and D. B. Denney, ibid., 1952, 74, 5912.2 7 H. L. Goering and C . Serres, jun., ibid., p. 5908.28 G. A. Haggis and L. N. Owen, J., 1953, 408.29 L. H. Darling, A. K. Macbeth, and J. A. Mills, ibid., p. 1364.30 G. A. Haggis and L. N. Owen, ibid., p. 399.31 Cf. C. W. Beckett, K. S. Pitzer, and R. Spitzer, J . Amer. Cltem. SOC., 1947, fig, 2488.32 G. A. Haggis and L. N. Owen, J . , 1953, 389.33 Idem, ibid., p. 40-1. 34 Idem, ibid., p. 408.W. J. Bailey and H. R. Golden, J . Amer. Chem. SOC., 1953, 75, 4780HALSALL : ALICYCLIC COMPOUNDS. 203methylcyclohexanone has the bromine atom e q ~ a t o r i a l . ~ ~ ~ 36 The deamin-ation of cyclohexylamines with simple alkyl substituents on the ring is con-formationally specific ; equatorial amino-groups afford alcohols of the sameconfiguration while axial groups are, in the main, eliminated.37, 38 Theconfiguration of cydohexane derivatives with one to twelve mutually identicalsubstituents has been discussed.39cycZoHeptane-1 : 2-diol and a number of its derivative^,^^ cy~looctanone,~~cis- and trans-cycl~octene,~~ and cyclooctyne 43 have been prepared.Hydr-oxylation of cis-cyclooctene with performic acid, and hydrolysis or solvolysiswith formic acid of cis-cyclooctene epoxide, yield cyclooctane-1 : 4-dio1,formed by a transannular reaction, as a major p r o d u ~ t . ~ ~ ~ 45 cis- and trans-cycZoNonene undergo similar reactions with performic acid giving, in bothcases, the same two stereoisomeric cyclononane-1 : 5-di0ls.~~ The formationof two isomers is probably due to participation of hydrcgen atoms from twodifferent CH, groups in the transannular reaction (cf.IV, V, and VI). An-[ HzIz--CH2 CH ,-CH , - C q h 'AoH+7 1I FH'OH -HcH ICH ,-CH 2 - C w ' / ( ! g o Hi+ HOnHC HCH[CH213-cH2 HCH .[CH2] 2CH2HLH.[CH2] 2*CH2 I(Va and b)(2 Isomers)other example of this type of reaction is the conversion of the products fromthe action of two mols. of N-bromosuccinimide on cyclononanone and oncyclodecanone into 4 : 5 : 6 : 7-tetrahydroindan-4-one and a mixture of trans-or-decalone and 1 : 2 : 3 : 4 : 5 : 6 : 7 : 8-octahydro-l-oxonaphthalene respect-ively by the action of dimeth~laniline.~7 Treatment of 2-bromocyclo-decanone with sodium methoxide gives cyclononanecarboxylic acid.47Dehydration and dehydrogenation of cyclodecane derivatives such as cyclo-decanol, carried out either concurrently or consecutively, yield azulene andnapht halene.48Energy differences between the stereoisomers of perhydrophenanthreneand between those of perhydroanthracene have been c a l ~ u l a t e d .~ ~The rings of the bicycZo[3 : 3 : Oloctane-2 : 5-dione (VII) areSome 4-substituted bicyclo[2 : 2 : 2]octane-l-carboxylic acids (VIII ; X = H,Br, OH, NH,, CO,Et, and CN) and their ethyl esters have been ~ynthesised.~~bicycZo[5 : 3 : O]Dec-l(7)-en-S-one (IX ; R = H) and related compounds35 E. J . Corey, J . Amer. Chem. SOC., 1953, 75, 2301.36 Cf. E. J. Corey, Expericntia, 1953, 9, 329.38 M.Mousseron and M . Mousseron-Canet, Compt. rend., 1953, 237, 391.30 R. Riemschneider and P. Geschke, Angew. Chem., 1953, 65, 390.40 L. N. Owen and G. S. Saharia, J . , 1963, 2583.41 F. F. Rlicke, J. Azuara, N. J. Doorenbos, and E. B. Hotelling, J . Amer. Chem. Soc.,43 A. T. Blomquist and L. H. Liu, ibid., p. 2153.44 A. C. Cope, S. W. Fenton, and C. F. Spencer, ibid., 1952, 74, 5884.45 C f . Ann. Reports, 1952, 49, 178.4 6 V. Prelog, K. Schenker, and W. Kung, Helu. Chinz. Ada, 1953, 36, 471.4 7 K. Schenker and V. Prelog, ibid., p. 896.4* Idem, ibid., p . 1181. 49 Cf. p. 217.51 H.-W. Wanzlick, Chem. Ber., 1953, 86, 269.5* J. D. Roberts, W. J. Moreland, jun., and W. Frazer, J . Amer. Chem. SOC., 1953,37 J. A. Mills, J ., 1953, 260.1953, 75, 5418. 42 A. C. Cope, R. A. Pike, and C. F. Spencer, ibid., p. 3212.G. Schroeter and G. Vossen; c f . Annalen, 1922, 426, 1.75, 637204 ORGANIC CHEMISTRY.have been obtained from cycloheptanone (X) as shown.= cis- and trans-10-MethyIdecal-cis-2-01 have been prepared. 54Hot H,PO,-H.CO,H Hg(OAc), t\C=C*~HRNEt, 0" + HEC*yHR NEt, - UoH(XITerpenes-Ruzicka 55 has summarised the structural features of themono-, sesqui-, di-, and tri-terpenes and, together with Eschenmoser andHeusser, has shown how the natural terpenes may be formed in Naturefrom four possible precursors, geraniol (XI), farnesol (XII) , geranylgeraniol(XIII), and squalene (XIV). He has suggested that the original isoprenerule, which required that the carbon skeleton of a terpene should be divisibleinto isoprene units, should be modified.The modified rule (" biogeneticisoprene rule ") requires that the carbon skeleton should be such that it canbe formed by an accepted reaction mechanism from a limited number of" isoprenoid '' precursors, possibly the four compounds mentioned above.As a result of the modification, and by assuming the possibility of carbon-carbon rearrangements, it follows that terpenes need not have the carbonskeleton of their precursors and hence may not obey the original isoprenerule.Monoterpenes-The positions of the double bonds in the enol-acetates ofcitral and citronella1 have been determined 56 and hydrogenation of theseacetates has been studied.57 The chemistry of the P-menthane-2 : 3-diolshas been 59 (&)-cis- and (+)-trans-Piperitol 6o and (+)- 61 and(-)-cis-carveol 62 have been prepared by reduction of (&)-piperitone and(+)- and (-)-carvone respectively.Such a compound is the sesquiterpene eremophilone (XV).53 A.M. Islam and R. A. Raphael, J., 1953, 2247.54 A. S. Hussey, H. P. Liao, and R. H. Baker, J . Amer. Chem. SOC., 1953, 75, 4727.5 5 L. Ruzicka, Experientia, 1953, 9, 357. 6 6 A. Riser, Bull. SOC. chim., 1953, 570.5 7 Idem, ibid., p. 691. 6 8 A. K. Macbeth and W. G. P. Robertson, J . , 1953, 895.58 Idem, ibid., p. 3512. 6o A. K. Macbeth, B.Milligan, and J . S. Shannon, ibid., p. 901.61 D. Lloyd and J. Read, Chem. a.tzd Ind., 1953, 436.R. H. Reitsema, J . Amer. Chem. SOC., 1953, 75, 1996HALSALL : ALICYCLJC COMPOUNDS.205Syntheses of +unsaturated monoterpene alcohols by routes involvingeither allylic bromination of monoterpenes followed by conversion of thebromo-derivative into the alcohol through the f ~ r m a t e , ~ ~ or direct oxidationwith mercury salts 64 have been described. Oxidation of terpenes such ascarvomenthene and a-pinene with tert.-butyl chromate yields ap-unsaturatedThe hydrocarbon (XVI) has been synthesised 66 and found to differ fromis~carvestrene.~~ Structures (XVII) and (XVIII) have been proposed forumbellulone dibromide and bromodihydroumbellulone,68 and (XIX) forcamphenamine.@ apoisoFenchene has been synthesised and its hydrationstudied. 70%HZMe MeI( X W (XVII) (XVI 11) ( X WLavandulic (XX), citronellic (XXI), and ,By-dihydrolavandulic (XXII)acid can be cyclised by an intramolecular acylation reaction to piperitenone(XXIII), pulegone (XXTV), and piperitone (XXV).'l Cyclisation of thecis- and tram-compounds of the geranic acid series,72 and synthesis of 2 : 7-dimethylocta-2 : 6(or 2 : 7)-dienoic acid and its cyclisation to (XXVI) 73have been described.H2?To I III 0% II 9% \/ I" (XXIII) * (XXIV) (XXV) CHO (XXVII)Condensation of crotonaldehyde and formaldehyde gives the dialdehyde(XXVII).74 A large number of reactions have been carried out with com-pounds with the carbon skeleton of (XXVII).74-7863 A.K. Macbeth, B. Milligan, and J. S. Shannon, J., 1953, 2574.65 G. Dupont, R. Dulou, and 0. Mondou, Bull. Soc. chim., 1953, 60.66 P.Sengupta, J . Org. Chem., 1953, 18, 249.6 7 K. Fisher and W. H. Perkin, jun., J., 1908, 1876.6 8 R. H. Eastman and A. Oken, J . Amer. Chem. Soc., 1953, 75, 1029.G9 E. E. van Tamelen, TV. F. Tousignant, and P. E. Peckham, ibid., p. 1297.i o S. Beckmann and R. Bamberger, Annalen, 1953, 580, 198.71 W. Kuhn and H. Schinz, Helv. Chim. Actn, 1953, 36, 161.72 H. Kappeler, H. Grutter, and H. Schinz, ibid., p. 1862.73 H. Kappeler, A. Eschenmoser, and H. Schinz, ibid., p. 1877.74 R. Pummerer, F. Aldebert, F. Buttner, F. Graser, E. Pirson, H. Rick, and H.75 F. Buttner, ibid., p. 184.7 6 R. Pummerer, F. Aldebert, and H. Sperber, ibid., p. 191.7 7 R. Pummerer and F. Graser, ibid., p. 207. '* R. Pummerer, F. Aldebert, F. Graser, and H. Sperber, ibid., p.225.W. Treibs, G. Lucius, H. Kogler, and H. Breslauer, Annalen, 1953, 581, 59.Sperber, Annalen, 1953, 583, 161206 ORGANIC CHEMISTRY.Total syntheses of nerol and geraniol, of the geometrical isomers of$-ionone, and of the ionones have been reported.79 Recent progress in thechemistry of the irones has been reviewed 8o and further work on the synthesisof the irones has been described.81 The use of infra-red spectra enables theisomers of ionone and irone to be distinguished.82 A small quantity ofa-ionone in the presence of p-ionone can be estimated colorimetrically.83The cyclisation of $-ionone (XXVIII) with boron trifluoride leads to(XXIX), (XXX), and (XXXI) in addition to the ionones. Similar cyclis-ations occur with citronellylidene- and geranyl-acetone and with +-irone.8*? 85(XXXT) 'Y L 1Sesquiterpenes and Diterpenes-The ultra-violet spectrum of +antoninproves that it is not an ap-unsaturated y-lactone, whilst infra-red evidenceconcerning the lactone ring is inconclusive.86 #-Santonin is now formulated9 R0'\/OH Oh(XXXV) >I-'( /ICH, (DL I (XXXVI)/\as (XXXII).Syntheses of two optically inactive stereoisomerides ofsantonin (XXXIII) 87 and of some analogues 88 have been described. Anoxidat ion product of hydroxyeremophilone (XXXIV) , formerly regarded as79 G. I. Samokhvalov, M. A. Miropol'skaya, L. A. Vakulova, and N. A. Preobrazhen-skiy, Doklady Akad. Nauk S.S.S.R., 1952, 84, 1179.8o Y.-R. Naves, Bull. SOC. chim., 1953, 561.82 Y.-R. Naves and J . Lecomte, ibid., p.112.83 P. Karrer and U. Blass. Helv. Chim. Acta, 1953, 36, 463.84 Y.-R. Naves and P. Ardizio, Bull. SOC. chim., 1963, 494.8 5 Y.-R. Naves, R. Wahl, P. Ardizio, and C. Favre, ibid., p. 873.8 6 W. G. Dauben and P. D. Hance, J. Amer. Chem. SOC., 1953, 75, 3352.88 M. Yanagita and A. Tahara. J. Org. Chenz., 1953. 18, 792.Y.-R. Naves and P. Ardizio, ibid., p. 296.Y. Abe, T. Harukawa, H. Ishikawa, T. Miki, M. Sumi, and T. Toga, ibid., p. 2567HALSALL : ALICYCLIC COMPOUNDS. 207C12H1803,89 is C1CH2S04 and has structure (XXXV).90 Pure zingiberenehas been i~olated,~l and a compound with its gross structure has been~ynthesised.~~ Calamenene has been shown by synthesis to be (XXXVI).93* 94(3- and y-Caryophyllene are geometrical isomers differing about the endo-cyclic double b ~ n d .~ ~ ~ 96 It is proposed that the name " (3-caryophyllene "be replaced by caryophyllene and " y-caryophyllene " by iso~aryophyllene.~~Proof of the geometrical isomerism comes from the conversion of caryo-phyllene (XXXVII) and isocaryophyllene (XLII) into the same diketone(XLI) as shown. The glycols (XXXIX) and (XLIV) and the keto-alcohols(XL) and (XLV) are not i d e n t i ~ a l . ~ ~ - ~ ' Caryophyllene reacts much fasterwith perphthalic acid than isocaryophyllene and is therefore the trans-isomer.96 The two oxides (XXXVIII) and (XLIII) differ only at (&X-Ray analysis 98 of the chloride and bromide corresponding to p-caryo-phyllene alcohol leads to (XLVI) for the latter and to (XXXVII) for caryo-phyllene.H H Me Me(XXXVII)Me(XXXIX)+cro*Me<HO' 'p-Caryophyllene alcohol is not dehydrated by acid to clovene althoughWith phos-HenceThese results are explained(XLIV) (XLIII) (XLI I)both are formed when caryophyllene is cyclised with a~id.~7, 99phoric oxide isoclovene (suggested structure XLVII) is f0rmed.~7caryophyllene cyclises by at least two routes.89 A.E. Bradfield, N. Hellstrom, A. R. Penfold, and J. L. Simonsen, J., 1938, 767.O0 T. A. Geissman, J . Amer. Chem. Soc., 1053, 75, 4008.9 1 V. Herout, V. BeneSovA, and J . Pliva, Coll. Czech. Chem. Comm., 1953, 18, 248.92 S. M. Mukherji and N. K. Bhattacharyya, J . Amer. Chem. Soc., 1953, 75, 4698.93 F. Sorm, K. VereS, and V. Herout, Coll. Czech. Chem. Comm., 1953, 18, 106.94 Cf.W. Treibs, Ber., 1949, 83, 530.O 5 A. Aebi, D. H. R. Barton, and A. S. Lindsey, Chem. and Ind., 1953, 487.g6 Idem, J . , 1953,3124.99 A. W. Lutz and E. 13. Reid, ibid., p. 278.9 7 A. W. Lutz and E. B. Reid, Chem. and I n d . , 1953, 749.J . M. Robertson and G. Todd, ibid., p. 437208 ORGANIC CHEMISTRY.if clovene is (XLVIII) with its methylene bridge opposite in configurationto that of p-caryophyllene alcohol (XLVI) .loo Further chemical evidence-Me(XLVI) (XLVII) ( XLVI I I)for the grouping *CH,*CH:CMe*CH,* in caryophyllene has been described.101Synthetic (+)-tram-caryophyllenic acid (XLIX) is identical with the acidobtained from caryophyllene. lo2Further evidence concerning humulene l o 3 9 lo4 supports its formulationas (L) or a closely related isomer differing only in an endo-exo-cyclic bondarrangement.lo51 lo6 ’~ /CH 2C02 HM e 4 7The structures of cedrene lo8 (LI) and cedrol (LII) have been eluci-dated.1m- 110 The key step is the proof that ring A is six-membered and notfive-membered as had been thought previously.The most probable con-figuration of cedrene is (LIII).lo9 A mechanism has been proposed for theconversion of bromonorcedrenedicarboxylic acid (LIV) into (LV). 111(LI) h eMeMeOH- +\MeLongifolene 112 contains a vinylidene ()C=CH2) 113 rather than a vinylThe environment of the former group has beenloo A. Aebi, D. H. R. Barton, and A. S. Lindsey, Chem. and Ind., 1953, 748.lol N. W. Atwater and E. B. Reid, ibid., p. 688.102 A. Campbell and H.N. Rydon, J . , 1953, 3002. lo3 J. 0. Harris, ibid., p. 184.lo4 R. W. Fawcett and J. 0. Harris, Chem. and Ind., 1953, 18.lo5 G. R. Clemo and J. 0. Harris, J . , 1952, (565.lo6 F. Sorm, M. Streibl, J. Pliva, and V. Herout, Coll. Czech. Chem. Comm., 1951, 16,lo* Cf. Sir John Simonsen and D. H. R. Barton, ‘‘ The Terpenes,” Cambridge Univ.log P. A. Plattner, A. Fiirst, A. Eschenmoser, W. Keller, H. Klaui, S. Meyer, and M.110 G. Stork and R. Breslow, J . Amer. Chem. Soc., 1953, ‘75, 3291111 Idem, ibid., p. 3292. 112 Cf. Sir John Simonsen and D. H. R. Barton, op. cit., p. 92.113 P. Naffa and G. Ourisson, Chem. and Ind., 1953, 917.group a s hitherto thought.639.Press, Vol. 111, p. 75.Rosner, Helv. Chim. A d a , 1953, 36, 1845.lo’ Cf. Ann. Reports, 1947, 44, 158HALSALL : ALICYCLIC COMPOUNDS.209determined chemically and shown to be represented by (LVI) where theatoms marked * are either fully substituted or at bridge-heads.l13 Longi-folene hydrochloride, the formation of which involves a molecular rearrange-ment of the camphene _+ bornyl chloride type, has been shown by X-rayanalysis to be (LVII) with the chlorine atom in the ertdo-c~nfiguration.~~~The chemical and X-ray results enable longifolene to be formulated as(LVIII). Molecular-rotation data show that (+)-longifolene is related to(+)-camphene, and (LIX) represents its absolute configuration. Longi-folene may be compared with p-santalene (LX) which, however, is relatedto - ) -camphene. 115Klyne 116 has applied the method of molecular-rotation differences tosome sequiterpene and diterpene stereochemical problems.Structures(LX1)-(LXV) are proposed for a- and p-cyperone, eremophilone, a-selinene,and dihydroeudesmol respectively. The conclusions concerning the lasttwo are supported by conformational arguments. 117 In the diterpene groupthe stereochemistry of the fundamental (unknown) hydrocarbons is as shown&XI) (LXII) (LXIII) (LXIV)IAbietane Pimarane Podocarpane 7 : 8-secopimarane(LXVI) (LXVII) (LXVI 11) (LXIX)in formulz (LXV)-(LXIX). Structures (LXX)-(LXXIII) are proposedfor abietic, lzvopimaric, Izeoabietic, and dextropimaric acid respectively.The stereochemistry of some y- and &lactones is also discussed, formula(LXXIV) being suggested for the lactone C1@@2 obtained by oxidationof sclareol and ambrein, and (LXXV) for ambreinolide.l16114 R.H. Moffett and D. Rogers, Chem. and Ind., 1953, 916.115 G. Ourisson, ibid., p. 918. W. Klyne, J., 1953, 30722 10 ORGANIC CHEMISTRY.Sandarakopiniaric acid probably differs from either dextro- or isodextro-pimaric acid at C(l) [cf. (LXXIII)], having the opposite configuration atthis centre.ll7\(LXX)(LXXIV)(LXXI)\(LXXII) (LXXI I I)(LXXV)(LXXVI) (LXXVII) (LXXVI I I)Marrubiin is a y-lactone and is now formulated as (LXXVI).118~119Infra-red and ultra-violet data concerning cafestol, l*O C20H2803, and someof its transformation products show that it contains an a-glycol groupingattached to a five-membered ring [cf. (LXXVII)] and a furan nucleus fusedto a six-membered ring.121 A further furan compound, methyl vinhaticoate,C,, H3,O,, isolated from Plathymenin reticdata, 122 is formulated as(LXXVIII).123 This structure does not conform to the " classical I ' isoprenerule.An acidic diterpene, along with a sesquiterpene, a triterpene acid, anda triterpene alcohol have been obtained from copal resin.12*Triterpenes and Related Compounds.-Structure (LXXIX) representsthe absolute configuration at C(,,, of the 3p-hydroxy-5a-steroids on thebasis of ( a ) correlation between unsaturated terpenes of known con-figuration and unsaturated steroids which results from a study of molecular-rotation differences 125 and (b) Prelog's asymmetric-synthesis method.126* lZ7l l i F.Petrii and V. Galik, Coll.Czech. Chem. Comm., 1953, 18, 717.l l S W. Cocker, B. E. Cross, S. R. Duff, J. F. Edward, and T. F. Holley, J., 1953,2540.l l 9 D. G. Hardy and W. Rigby, Chem. and Id., 1953, 1150; cf. W. Cocker, J. T.Edward, and T. F. Holley, ibid., p.'!227.120 L. F. Fieser and M. Fieser, Natural Products Related to Phenanthrene," Rein-hold Publ. Corpn., New York, 3rd Edn., 1949, p. 79.n1 C. Djerassi, E. Wilfred, L. Visco, and A. J. Lemin, J . Org. Chem., 1953, 18, 1449.lZ2 F. E. King, T. J. King, and K. G. Neill, J., 1953, 1055.lZ3 F. E. King and T. J . King, ibid., p. 4158.P. Fournier, Bull. Soc. chim., 1953, 32.lZ5 J. A. Mills, J., 1952, 4982; see also idem, Chem. and Ind., 1953, 218.lZG V. Prelog, Helv. Chim. Ada, 1953, 36, 308.12' W. G. Dauben, D.F. Dicltel, 0. Jeger, and V. Prelog, ibid., p. 325HALSALL : ALICYCLIC COMPOUNDS. 21 1The relative st ereochemistry of lanosterol (LXXX) and p-amyrin (LXXXI)has already been elucidated and in both compounds the terminal ring A isof the same enantiomeric type as that of the 5a-ster0ids.l~~ Hence theabsolute configuration of lanosterol and p-amyrin must be as in (LXXX)and (LXXXI). This conclusion has been confirmed for lanosterol andu-amyrin,lZ7 ring A of which is the same as that of p-am~rin.l~~ A directrelation between lanosterol and p-amyrin has been established by the con-version of lanosterol and manool (LXXXII) into the same acid (LXXXIII) ,130manool having already been related to p - a m ~ r i n , ~ ~ ~ In view of the closestereochemical relation between steroids, lanosterol, and p-amyrin, steroidnumbering is now used for rings A and B of p-amyrin and related triterpenes(cf.LXXXI).131(LXXIX) (LXXX) (LXXXI)Tetracyclic. The evidence previously presented 132 concerning lanosterolhas, in some instances, been described more fully.133-135 Additional evidencesupporting structure (LXXX) has been p ~ b l i s h e d . l ~ ~ - l ~ ~ Lanosterol hasbeen converted into an analogue of provitamin D3,139 and into 14-methyl-pregn-4-ene-3 : 11 : 20-trione 140 which has the same activity in the Corner-Allen test as the corresponding progesterone derivative. 55cycZoArteno1 l4I7 142 is a ~ycZolanost-24-enol.~~~ The presence of an iso-propylidene group in a side chain, and of a cyclopropane ring had alreadybeen shown.l*l cycZoArtany1 acetate has now been isomerised by hydrogenchloride to a mixture of isomers, the major component of which is lanost-9(11)-enyl acetate.143 This suggests that the cyclopropane ring extendsfrom C(g), and infra-red data indicate that it contains a CH, group.144128 Cf. Ann.Reports, 1952, 49, 184. 129 Cf. L. Ruzicka, Experienlia, 1953, 9, 360.130 E. Kyburz, B. Riniker, H. R. Schenk, H. Heusser, and 0. Jeger, Heh. Chim.131 J. M. Guider, T. G. Halsall, and E. R. H. Jones, J., 1953, 3024.132 Ann. Reports, 1952, 49, 184.133 J . Fridrichsons and A. McL. Mathieson, J., 1953, 2159.13* C. S. Barnes, D. H. R. Barton, A. R. H. Cole, J. S. Fawcett, and B. R. Thomas,135 C . S. Barnes, D. H. R. Barton, J. S. Fawcett, and B.R. Thonas, ibid., p. 576.136 C. S. Barnes and D. H. R. Barton, ibid., p. 1419.lS8 S. A. Knight, J. F. McGhie, and M. J. Birchenough, Chem. and I n d . , 1953, 822.130 D. H. R. Barton and B. R. Thomas, J.. 1953, 1842.140 W. Voser, H. Heusser, 0. Jeger, and L. Ruzicka, Helv. C h i m . Acta, 1953, 36, 299.141 D. H. R. Barton, J., 1951, 1444.lb2 S. Chapon and S. David, Bull. Soc. chim., 1952, 456.143 H. R. Bentley, J . A. Henry, D. S. Irvine, and F. S. Spring, Chent. and I n d . , 1953,Acta, 1953, 36, 1891.ibid., p. 571.J. F. McGhie, M. K. Pradhan, and W. A. Ross, ibid., p. 305.217; J., 1953, 3673. 144 A. R. H. Cole, Chem. and I n d . , 1953, 946212 ORGANIC CHEMISTRY.cycZoArteno1 is therefore either (LXXXIV) or (LXXXV).may be cycloartenol.143Handianol 145\AOH/\/-Me(LXXXI I) (LXXXIII) (LXXXIV) (LXXXV)Eburicoic acid (LXXXVI) 146-148 and polyporenic acids A,149-154 B,155and C 156 (LXXXVII, LXXXVIII, LXXXIX) have been shown to possessthe 4 : 4 : 14-trimethylergostane skeleton with thirty-one carbon atoms.They thus form another group, distinct from the lanosterol group, of tri-met hyl-st eroids.Eburicoic acid has been converted into lano~t-8-ene.~~~ The methodinvolves removal of the C(,,-hydroxyl group by oxidation and Wolff-Kishnerreduction, removal of the methylene group by ozonolysis and reduction ofthe resulting ketone, and conversion of the carboxyl group into methyl.(LXXXVI) (LXXXVII) (LXXXVI 11)07-0(XC)The position of the methylene group is shown by addition of hydrogenchloride to methyl 0-acetyleburicoate, followed by dehydrochlorination andozonolysis of the product, methyl isopropyl ketone being obtained.14*Oxidation of 0-acetyleburicoic acid with selenium dioxide gives the lactoneG.A. Gonzalez and A. Calero, ibid., 1950, 46, B, 175.145 G. A. Gonzalez, ,4. Calero, and R. Calero, Anal. Fis. Quim., 1949, 45, B, 1441 ;146 R . M. Gascoigne, A. Robertson, and J . J. H. Simes, J . , 1953, 1830.14’ J. S. E. Holker, A. D. G. Powell, A. Robertson, J. J. H. Simes, and R. S. Wright,14* J. S. E. Holker, A. D. G. Powell, A. Robertson, J . J. H. Simes, R. S. Wright,149 R. G. Curtis, (Sir) Ian Heilbron, E. R. H. Jones, and G. F. Woods, ihid., p. 457.150 E. R. H. Jones and G. F. Woods, ibid., p. 464.151 T.G. Halsall, E. R. H. Jones, and A. J . Lemin, ibid., p. 468.15, T. G. Halsall and R. Hodges, ibid., p. 3019.153 M. Roth, G. Saucy, R. Anliker, 0. Jeger, and H. Heusser, Helv. Chim. Acts, 1953,lb4 T. G. Halsall, R. Hodges, and E. R. H. Jones, personal communication.155 T. G. Halsall and E. R. H. Jones, XIIIth Int. Congr. Pure Appl. Chem., Stock-156 A. Bowers, T. G. Halsall, E. R. H. Jones, and A. Lemin, J., 1953, 2548.ibid., p. 2414.and R. M. Gascoigne, ibid., p. 2422.36, 1908.holm, July 29th, 1953HALSALL : ALICYCLIC COMPOUNDS. 213(XC) which fixes the position of the carboxyl group. The position of thehydroxyl group has been shown by phosphorus pentachloride dehydration. 15'Polyporenic acid C has been converted into methyl O-acetyldehydro-eburicoate (XCII) as shown.lS5 The carbonyl-oxygen atom in acid C is atC(3) since infra-red data indicate that it is on a six-membered ring.156 Theinfra-red spectrum of (XCI) has a band characteristic of a keto-group in aMe polyporenate Eburicoic acidCrO, + t MeozCnJ1A A P CH,OP\/ A v (XCI) -4CO'X (XCII)Me02C X k ( i ) NaBH, ; *(ii) W.-K.redn *A V > : o ;i-< --y-7-& (iii) CH,NU,; (iv) Ac,O ,q(!(JI CH2(* Reduces C(,):O.) I3 I IIfive-membered ring. The hydroxyl group of acid C is therefore at eitheror Ccle). A decision in favour of c(16) can be made from molecular-rotation data.156 It has been suggested tentatively 156 that the hydroxylgroup has the p-configuration, but it is probable, in view of the change inrotation on a ~ e t y l a t i o n , ~ ~ ~ that the configuration is a (cf.LXXXIV).Polyporenic acid B is closely related to polyporenic acid C and both havebeen converted into (XCIII).155The evidence for the structure of polyporenic acid A is based partly onstudies of the oxidation of derivatives of methyl polyporenate A whichelucidated the nature of rings B and c,151 on dehydration experiments whichprove that there is a 3whydroxyl group,152 and on degradation of the sidechain as shown.152 These facts, together with the probable biogeneticS H 2 y; Heat 7H3 yH3 0, Y H 3 R.CH2*C- H C02H __t R*CH,.C=CH + R.CH,.C=O + CH,*CHO(i) PhMgBr ;(ii) -HIO I 0 sRC0,Me --- RCHO + R*CH=z?:relation of polyporenic acids A, B, and C, led to structure (LXXXVII) forpolyporenic acid A.152 The proof of this structure has been completed by(XCIV) Athe conversion of the acid and of lanosterol into the common degradationproducts (XCIV) 153 and (XCV).15*The action of hydrogen chloride on euphol 159 and butyrospermol 16015' R.M. Gascoigne, J. S. E. Holker, B. J. Ralph, and A. Robertson, J . , 1951, 2346.15* Cf. D. K. Fukushima and T. K. Gallagher, J . Amer. Chem. SOC., 1951, 73, 196.158 M. C. Dawson, T. G. Halsall, and R. E. H. Swayne, J., 1953, 590.160 M. C. Dawson, T. G. Halsall, E. R. H. Jones, and P. A. Robins, &id., p. 586214 ORGANIC CHEMISTRY.has been described, and the chemistry of the elemi acids discussed.161 Thestructure of euphol has been discussed in the light of its possible biogene~is.~~Tetracyclosqualene is (XCVI).162Olean-9( 11) : 13 (1 8)- and olean-9( 11) : 18-dienol have beenprepared and p-amyrin has been converted into germanic01.l~~ Taraxerol 164Pentacyclic.and skimmiol 165 are identical,166, 167 being probably 13a-olean-18-en-3p-01(1 3-isogermanicol) .166 Arjunolic acid, a new triterpene from Terminaliaarjuna, has been provisionally formulated as (XCVII).168The structure (XCVIII) suggested for quinovic acid 169 has been con-firmed,170 but a new structure (XCIX) has been advanced for its dehydrationproduct, novic acid.170 I t is suggested that the first stage of the Liebermannand the Salkowski colour reactions is the formation of a conjugated dienesystem.171 In support of this view ursolic acid has been converted withconcentrated sulphuric acid into a diene for which structure (C) is sug-gested.171 However, by analogy with the structure of novic acid, (CI)seems more likely.Phyllanthol 172 contains a cyclopropane ring and gives a-amyrin on treat-By a study of the oxidation of the deuterated a-amyrinobtained by treating phyllanthol with deuterium chloride it has been shownthat phyllanthol is not 9 : 12- or 11 : 13-cyclo-a-amyranol.Possible struc-tures have been discussed.Further evidence for structure (CII) for asiatic acid has been re~0rted.l‘~The location of the carboxyl group is not yet proved. It could be at C(14),ment with acid.173161 T. G. Halsall, G. D. Meakins, and R. E. H. Swayne, J., 1953, 4139.162 G. Buchi; cf. L. Ruzicka, Experientia, 1953, 9, 363.163 J .M. Beaton, J. D. Johnston, L. C. McKean, and F. S. Spring, J., 1953, 3660.164 S. Burrows and J. C. E. Simpson, J . , 1938, 2042.165 K. Takeda, J . Pharm. SOC. Japan, 1941, 61, 117, 506 (with S. Yosiki) ; 1942, 62,167 Cf. ‘‘ Elsevier’s Encyclopaedia of Organic Chemistry,” Vol. 14s (1952), p. 1190s.169 0. Jeger, “ Fortschritte der Chemie organischer Naturstoffe,” Springer-Verlag,Berlin, 1950, Vol. VII, p. 69; A. Brossi, B. Bischof, 0. Jeger, and L. Ruzicka, Helv. Chim.A d a , 1951, 34, 244.171 C. H. Brieskorn and L. Capuano, Chem. Ber., 1953, 86. 866.172 K. B. Alberman and F. B. Kipping, J., 1951, 2296.l i 3 D. H. R. Barton and P. de Mayo, J . , 1953, 2178.l T 4 J. Polansky, Bull. SOC. chim., 1953, 173.390; 1943, 63, 193, 197. 166 C.J. W. Brooks, Chem. and Ind., 1953, 1178.F. E. King, Chem. and Ind., 1953, 1325.D. H. R. Barton and P. de Mayo, J . , 1953, 3111HALSALL : ALICYCLIC COMPOUNDS. 215but this is unlikely since asiatic acid does not undergo the ready thermaldecarboxylation typical of a py-unsaturated acid. Ursa-ll(l3) : 18-dienolhas been prepared.175Lupene-I (CITI) and taraxastene (CIV) have been converted into acommon product (CV).176 At first it was thought that lupene-I had itsC<,,,-methyl group in the equatorial conformation, but it now appears thatit is in the axial conformation and that lupene-I and taraxastene have thestructures indicated.177INew triterpenes isolated include the alcohols resiniferol 178 and ilexol, 179a ketone C,,H,,O from Alnus g2utinosa,ls0 and the lactone thurberogeninC,,H,,O from the cactus Lemaireocereus Thurberi.181 Further evidence forthe existence of crataegolic acid has been put fonvard.ls2Triketones. The structure (CVI) for flavaspidic acid has been proved byits disproportionation to albaspidin (CVII) and by synthesis.183 A newsynthesis of filicinic acid (CVIII) is described. ls4 Cohumulone, whichresembles humulone in its behaviour, is converted by hot alkali into isobutyr-aldehyde, 4-methylpent-3-enoic acid, and cohurnulinic acid. 185hle\,Me2CH20 0 OH(CW (CVI I) (CVI I I)T. G. H.175 J. D. Easton, W. Manson, and F. S. Spring, J . , 1953, 943.176 J. L. Beton, A. Bowers, T. G. Halsall, and E. R. H. Jones, Chem. and Ind., 1953,17* G. Dupont, M.Julia, and W. R. Wragg, Bull. SOC. chim., 1953, 852.l i e H. Iseda, J . Pharm. SOC., Japan, 1952, 74, 1064; S. Iseda, ibid., p. 1611.180 S. Chapon and S. David, Bull. SOC. chim., 1953, 333.181 C. Djerassi, L. E. Geller, and A. J. Lemin, J . Amer. Chem. SOC., 1953, 75, 2254.lE2 R. Tschesche, A. Heesch, and R. Fugmann, Chem. Bey., 1953, 86, 626.lE3 A. XlcGookin, A. Robertson, and T. H. Simpson, J., 1953, 1828.E. B. Reid and T. E. Gompf, 1. Amer. Chem. SOC., 1953, 75, 1661.l o 5 G. A. Howard and A. R. Tatdhell, CJtem. and Ind.. 1953. 436847. 1 7 7 Cf. ibid., p. 1387216 ORGANIC CHEMISTRY.Steroids.Stereochemistry.-Important contributions were lately made to theproblem of absolute configuration. There is a fairly strong chain of evidencecorrelating D-glyceraldehyde with a number of cyclic terpeneslcollected data on the molecular optical rotation [MD] of several pairs ofepimeric, terpenoid cyclohex-2-enols and their esters ; by assuming thatthe ascribed configurations were correct it could be deduced that an alcoholrepresented as in (I) is more lzvorotatory than the epimer (11).The differ-ences are large, and are greatly enhanced by esterification.Mills(1) (11)When this rule was appliedsteroid alcohols, the differences(111) (IV)to seven known pairs of epimeric, allylicfound were those predictable if the con-vent ional steroid project ion represented truly the Bbsolute configuration.An eighth pair furnished a dubious exception. In a later note3 the con-figurational and conformational resemblances between (+)-menthol (111)and the conventional representation of ring B in a 7p-hydroxy-5a-steroid(IV) , and similarly between (-)-neomenthol and the 7a-steroid epimer,were pointed out.Here again the signs and magnitudes of the molecularrotation differences, when the steroid and terpenoid series were compared,supported the view that the steroid convention is spatially correct.Prelog and his associates advanced arguments which, if valid, permitthe assignment of configuration to certain optically active alcohols bydetermining the sign of rotation of the atrolactic acid produced from thephenylglyoxylic esters by reaction with methylmagnesium bromide andsubsequent hydrolysis. Androsten-l7p-01, cholestan-7a- and -7p-01, and5a-pregnan-20p-01 were examined. In each case the isolated atrolactic acidhad the sign of rotation to be expected if the conventional steroid projectionis assumed to be correct.These conclusions of Mills and of Prelog on the absolute configurationof steroids are in conflict with the view tentatively advanced by Lardon andReichstein and based on studies of a p-methoxyadipic acid derived fromcalcif erol.Turner computed the difference of internal energy (vapour phase, 25")between cis- and trans-decalin, using the values deduced by Pitzer for theenergy associated with different conformations of the n-butane portion of ahydrocarbon chain.The value obtained, 2.4 kcal., agreed well with experi-ment. observed that the result could be reached more simply byassigning the value zero to trans-decalin (V).Compared with (V), cis-A. J. Birch, Ann. Reports, 1950, 47, 191.J. A. Mills, J . , 1952, 4976; cf. W. Klyne, Helv. Chim. Acta, 1952, 35, 1224.J. A. Mills, Chew and Ind., 1953, 218.A. Lardon and T. Reichstein, Helv. Chim. Ada, 1949, 32, 2003.R. B. Turner, .T. Amer. Chem. SOL, 1952, 74, 2118.K. S. Pitzer, Chem. Reviews, 1940, 27, 39.W. S. Johnson, J . Amer. Chem. SOL, 1953, 75, 1498.JohnsoCORNFORTH : STEROIDS. 217decalin (VI) has three additional “skew” arrangements (shown by thebroken lines) of four-carbon portions of the molecule.associated with an energy-increase of 0-8 kcal.; the total energy differenceEach of theseis therefore 2.4 kcal. An analysis was made in this manner of the perhydroanthracenes and perhydrophenanthrenes : the relative values for internaenergy are given in the Table.Perhydro- Perhydro-anthracenes AE (kcal.) phenanthrenes AE (kcal.)trans-syn-trans 0 trans-anti-trans 0.8cis-syn-trans 2.4 trans-anti-cis 3.2cis-anti-cis 4.8 cis-syn-trans 3.2trans-anti-trans h5.6 cis-anti-cis 4.8cis-syn-cis - 6.4 cis-syn-cis - 7.2Ivans-syn-trans >/ 5.6Several papers were published on the configurations of x-bromo-ketones.Bromination products of several 3-oxosteroids were examined by FieseIand his collaborators.* The method may be exemplified : methyl 4-bromo-3-oxocholanate (VII) was reduced by sodium borohydride to a mixture oftwo bromohydrins (VIII, IX).With alcoholic alkali one of these gavea 3 : 4-epoxide (X), the other 3-oxocholanic acid (XI).The isomer (IX) wasalso converted by hydrogenation into 3p-hydroxycholanic acid (XII). Fromthe evidence obtained by Bartlett from cis- and trans-2-chlorocyclohexanol,the bromohydrin giving an epoxide is a trans-bromohydrin, and its epimerwhich yields a ketone is a cis-bromohydrin. From the conversion (IX __tXII) it follows that the bromine atom in (VII) is p-oriented. By similarmethods a 8-oriented bromine atom was attributed to 4-bromo-17p-hydroxy-testan-3-one. 2-Bromocholestan-3-one was a t first thought to have the28-configuration; but this erroneous conclusion was traced to a failure toseparate the two bromohydrins formed on reduction, and the evidence8 L. F. Fieser and R. Ettorre, J .Amer. Chem. SOC., 1953, 1700; L. F. Fieser and J. A.Dominguez, ibid., p. 1704. 0 P. D. Bartlett, ibid., 1935, 57, 224218 ORGANIC CHEMISTRY.actually established the 2a-configuration as correct. lo 2-Chlorocholestan-%one is also the 2a-epimer.llWhen the infra-red spectra of steroid a-bromo-ketones of known con-figuration were compared with the spectra of the parent ketones, it wasobserved l2 that where the carbon-oxygen and carbon-bromine bonds layapproximately in the same plane the carbonyl absorption band was shiftedto higher (13-25 cm.-l) frequencies; if the bonds were far from coplanarthe effect was slight. By applying this rule to 2-bromocyclohexanone andseveral alkyl-substituted analogues, Corey l3 concluded that the preferredconfiguration of the bromine atom in 2-bromocyclohexanone was axial, butthat this effect could be overcome by the steric repulsion from neighbouringaxial substituents.The information gathered from monocyclic ketoneswas applied to steroid a-bromo-ketones. Thus, in a pair of epimeric a-bromo-ketones the thermodynamically stable epimer could be indicated : this is theepimer which would preponderate after equilibration of either epimer withhydrogen bromide. This more stable epimer is not necessarily the initialproduct of bromination ; Corey proposed the rule that the epimer having anaxial bromine atom is always formed more rapidly. Complete agreementbetween predicted and proved configurations of a-bromo-ketones was claimed.Some evidence on the conformation of ring A in steroid ketones wasprovided by measurements l4 of the dipole moments of androstane-3 : 17-dione and testane-3 : 17-dione.If both these substances have the (' all-chair " conformation of the six-membered rings, calculation indicates thatthe dipole moments should be identical ( 3 . 0 4 ~ ) . The observed momentswere 3.1 and 3.5 respectively. It was suggested that the " boat " con-formation of ring A (calculated moment 5.28 D) appears to the extent ofsome 16% in testane-3 : 17-dione under the experimental conditions. Thedata do not exclude the possible presence of a similar proportion of " boat "form (calculated moment 3.58 D) in androstane-3 : 17-dione.In an important contribution to the stereochemistry of steroid sapogeninsit was shown l5 that sarsasapogenin and smilagenin (stereoisomers of struc-ture XIII) differ in configuration at C(25).The $-genins (XIV) and dihydro-genins (XV; R = OH) from the two sapogenins were found to be different,contrary to earlier reports; l6 moreover, the two $-genins were each recon-verted by acid quantitatively into the parent genin. Oxidation of $-sarsa-lo E. J. Corey, J . Amer. Chem. SOC., 1953, 75, 4833; L. F. Fieser and W.-Y. Huang,ibid., p. 4837.l 1 J. J. Beereboom, C. Djerassi, D. Ginsburg, and L. F. Fieser, ibid., p . 3500.l2 R. N. Jones, D. A. Ramsay, F. Herling, and K. Dobriner, ibid., 1952, 74, 2828;R. N. Jones, ibid., 1953, 75,4839. 13 E. J. Corey, ibid., p. 2301 ; Experientia, 1953,9,329.l4 H. R. Nace and R. B. Turner, J .Amer. Chem. SOC., 1953, '75, 4063.l6 R. E. Marker and E. Rohrmann, ibid., 1939, 61, 846; idem and E. M. Jones, ibid.,I. Scheer, R. B. Kostic, and E. Mosettig, ibid., p. 4871.1940, 62, 648CORNFORTH : STEROIDS. 219sapogenin afforded (+)-a-methylglutaric acid (containing all the carbonatoms of ring F), whereas $-smilagenin gave (-)-a-methyglutaric acid.Reduction of the 26-toluene-fi-sulphonates (XV ; R = +-C,H,Me-SO,*O) ofthe dihydrogenins by lithium aluminium hydride gave the same deoxy-compound (XV; R = H). Hence, unless formation of the dihydrogeninsis attended by inversion at C(22) in one series but not in the other, sarsa-sapogenin and smilagenin differ only at C(25). I t has been stated l6 thatisosarsasapogenin, formed by acid isomerisation of sarsasapogenin, is identicalwith smilagenin.If this is true, the acid isomerisation is an inversion at C(25).Such an inversion might possibly occur by addition of a proton to the oxygenatom of ring F ; then if the 27-methyl group had the axial configuration thisproton would be rather well placed to initiate a displacement reaction withinversion of configuration at CCz5) (XVI XVII). The reaction mightMebe reversibIe. Further research is undoubtedly needed to establish theexact relation between members of the " normal " and the " is0 "-series ofsapogenins, for the above evidence l5 suggests that other small differencesbetween non-identical substances may have been overlooked. Hecogeninand diosgenin were recently 1 7 correlated with smilagenin by oxidation ofthe +-genins to (-)-a-methylglutaric acid.From hecogenin by a differentroute, (+)-methylsuccinic acid was obtained. This incident ally correlates(+)-methylsuccinic acid with (-)-a-methylglutaric acid, as already inferredby Fredga.l*The formulation of lumisterol as 10-efiiergosterol was confirmed byX-ray crystallographic analysis of its 4iodo-5-nit robenzoat e.Total Synthesis.-A synthesis of ( &)-cortisone acetate was reported.20This is essentially a modification of the Harvard synthesis; 21 space doesnot permit an extended review, but it is remarkable that selection of experi-mental techniques made possible the elaboration of the 1 l-oxo-group froma 9 : ll-double bond, and the construction of ring D and its side-chain,while retaining a A4-3-oxo-group unprotected in ring A.The method usedto construct the side-chain after the characteristic closure of ring D~~ isnoteworthy ; it is illustrated in partial formula3 (XVIII _+ XIX).Details of the Oxford total synthesis 22 and of intermediate stages in theMerck total synthesis 23 were reported.l7 V. H. T. James, Chent. and I n d . , 1953, 1388.la A. Fredga, Arkiv Kemi Min., Geol., 1947, 24, A , No. 32.D. Crowfoot Hodgkin and D. Sayre, J., 1952, 4561.2o L. I3. Barkley, M. W. Farrar, W. S. Knowles, and H. Raffelson, J . Amer. Chem.SOC., 1963, 75, 4110. 21 A. J . Birch, Ann. Reports, 1951, 48, 200.22 H. M. E. Cardwell, J. W. Cornforth, S. R. Duff, H. Holtermann, and Sir R.Robinson, J . , 1953, 361 ; see ref.21.23 G. I. Poos, G. E. Arth, R. E. Beyler, and L. H. Sarett, J . Amer. Chem. Soc., 1953,75, 422; R. M. Lukes, G. I. Poos, R. E. Beyler, W. F. Johns, and L. H. Sarett, ibid.,p. 1707; L. H. Sarett, W. F. Johns, R. E. Beyler, R. M. Lukes, G. I. Poos, and G. E.Arth, ibid., p. 2112; see Ann. Reports, 1952, 49, 190220 ORGANIC CHEMISTRY.A total synthesis of striking simplicity, leading to (-+@androsterone,was announced24 by W. S. Johnson and his associates. 5-Methoxy-2-tetralone (XX) was condensed successively with l-diethylaminopentan-3-onemethiodide and with methyl vinyl ketone to give the tetracyclic methoxy-ketone (XXT). Reduction of this substance with lithium and ethanol inMe ,.‘? x2H CHOMe I,*‘? ‘I 1 /- - ‘IA; - /- /--(XVIII)Diazo-ketonesynthesisIiquid ammonia afforded a mixture containing the ketones (XXII), onehaving a 13 : 14-, the other a 16 : 17-, doubIe bond (homosteroid numbering).After hydrogenation, the hydroxy-ketone (XXIII) was isolated.The secondangular methyl group was introduced by methylation of a furfurylidene - - w Y eO A J U(XX)0 0Several___tstagesderivative : ozonolysis of the product (XXIV) gave a dicarboxylic acid whichwas cyclised to (-J=)-e$iandrosterone (XXV). The methylation also pro-duced, unfortunately, a larger amount of the undesired 13-epimer, which wassimilarly converted into ( &- ) -1umiepiandrost erone.24 W. S. Johnson, B. Bannister, B. M. Bloom, A. D. Kemp, R. Pappo, E. R. Rogier,and J . Szmuszkovicz, J . Amer.Chem. SOL, 1953, 75, 2275CORNFORTH : STEROIDS. 22 1The conversion of (XXI) into (XXIII) produces six new centres ofasymmetry, yet the desired stereoisomeride (XXIII) was the major product.This spectacular success is a measure of the increased knowledge, acquiredduring recent years, of the stereochemistry of fused alicyclic rings.Wilds and his collaborators 25 completed a total synthesis of which earlierstages have already been published.26 The monoethylene ketal (XXVI) ofa ketone which is available 26 from dihydroresorcinol by two ring-extensionsand a partial hydrogenation was methylated via the hydroxymethylenederivative. Sodiotriphenylmethane and methyl bromoacetate then gave,after hydrolysis, a mixture of two epimeric acids (XXVII) which wereseparated and converted into the methyl ketones (XXVIII) by reaction of(XXVI) (Two epimers)(XXXI) (XXW (XXIX)the acid chlorides with tert.-bu tyl malonate and acid-catalysed decarboxyl-ation.Cyclisation (sodium methoxide) to the cyclopentenones (XXIX) wasfollowed by carboxylation (methyl carbonate-sodium hydride) to the keto-esters (XXX) . Vigorous hydrogenation (platinum-acetic acid-hydro-chloric acid) and reoxidation (chromic acid) produced, from one isomer,methyl (&)-3-oxoetianate (XXXI). Thus another method for constructingring D has been successfully applied.A total synthesis of D-homosteroids, starting from 2-methylcyclohexane-1 : 3-dione, was reported from the Ciba 1ab0ratorie.s.~~ Condensation of thedione with ethyl 7-chloro-5-oxoheptanoate (obtained from ethylene, alumin-ium chloride, and the ester chloride of glutaric acid) in the presence of tri-ethylamine gave the trioxo-ester (XXXII).Conditions for cyclization to(XXXIII) needed careful choice, to avoid fission of the 1 : 3-dione : triethyl-amine benzoate in boiling xylene was found satisfactory. Hydrogenationand alkaline hydrolysis then gave two acids (XXXIV), which were separated.The more abundant isomer was found (see below) to have the desired con-figuration. Ring B was constructed by protecting the carbonyl groups (asethylene ketals) while the carboxyl group was converted into the ethyl25 A. L. Wilds, J. W. Ralls, D. A. Tyner, R. Daniels, S. Kraychy, and M. Harnick,2E A. L. Wilds, J. W. Ralls, W. C. Wildman, and K.E. McCaleb, ibid., 1950, 72, 5794.2 7 P. Wieland, H. Ueberwasser, G. Anner, and K. Miescher, Helv. Chim. Acta, 1953,J . Amer. Chem. SOC., 1953, 75, 4878.36, 376, 1231 ; P. Wieland, G. Anner, and K. Miescher, ibid., p. 646222 ORGANIC CHEMISTRY.ketone by reaction of ethylmagnesium bromide with the dimethylamide ;hydrolysis of the ketal groups and alkaline cyclization then gave the un-saturated tricyclic ketone (XXXV). The configuration of this substance was0 0 0__+(XXXII) (XXXIII) (XXXIV; two isomers)0 0 t o Atti+ Me,?$ + py$, Me1 ,q$ H{\I/H\i/HV AVVHVOP\/I0 9 V A V O P \ A /(XXXVII; two isomers) (XXXVI; two isomers) (XXXV)proved by correlation with an intermediate in the Harvard total synthesis.21Addition of ring A was then effected by means of methyl vinyl ketone; twost ereoisomerides (XXXVI) were produced, one of which could be hydro-genated, stepwise, to a mixture of (&)-D-homoandrostanedione and (-j)-~-homotestanedione (XXXVII).The optically inactive products of this andof the other total syntheses were identified by infra-red spectrography.11 -Oxygenated Steroids.-The transformation of readily accessible sub-stances into 11-oxygenated steroids was again the subject of a larger numberof papers than appeared on any other topic in this field.A series of papers gave details for the introduction of an lla-hydroxy-group into pregnane derivatives by incubation with growing cultures ofRihizopus nigricans.28 The substances hydroxylated in this way at Ctll)included deoxycorticosterone,29 17a-hydroxy-11-deoxycorticosterone (Reich-stein’s substance S ; XXXVIII),30 17cc-hydro~yprogesterone~~~ pregna4 : 6-diene-3 : 20-dioneJ32 and pregnane- and allopregnane-3 : 20-di0ne.~~ Pregna-4 : 16-diene-3 : 20-dione was transformed by the same organism into l l a -hydroxy-17a-progesterone, isomerized by acid to 11 a-hydroxypr~gesterone.~~Cortisone acetate (XXXIX) is thus available 30 from substance S (XXXVIII)28 See Ann.Reports, 1952, 49, 195-196; the sentence referring to R. nigricans ismisplaced and should precede the sentence on p. 185 beginning “ This microbiologicalhydroxylation . . .”29 S. H. Eppstein, P. D. Meister, H. C. Murray, H. M. Leigh, D. A. Lyttle, L. M.Reineke, and A. Weintraub, J . Amer.Chem. Soc., 1953, 75, 408.30 D. H. Peterson, S. H. Eppstein, P. D. Meister, B. J. Magerlein, H. C. Murray,H. M. Leigh, A. Weintraub, and L. M. Reineke, ibid., p. 412.31 P. D. Meister, D. H. Peterson, H. C. Murray, G. B. Spero, S. H. Eppstein, A. Wein-traub, L. M. Reineke, and H. M. Leigh, ibid., p. 416.32 D. H. Peterson, A. H. Nathan, P. D. Meister, S. H. Eppstein, H. C. Murray, A.Weintraub, L. M. Reineke, and H. M. Leigh, ibid., p. 419.33 S. H. Eppstein, D. H. Peterson, H. M. Leigh, H. C. Murray, A. Weintraub, L. M.Reineke, and P. D. Meister, ibid., p. 421.34 P. D. Meister, D. H. Peterson, H. C. hlurray, S. H. Eppstein, L. M. Reineke,A. Weintraub, and H. M. Leigh, ibid., p. 56CORNFORTH STEROIDS. 223in three stages, each proceeding in good yield : 11 a-hydroxylation, selectiveacetylation a t Ctzl>, and oxidation.COCH,*OH CO*CH,*OAcThe acetate (XLIII; R = Ac) of cortisol (“ Hydrocortisone,” 17a-hydroxy-corticosterone) was obtained 35 from 3a : 17a-dihydroxypregnane-11 : 20-di-one (XL) , readily available from 11 a-hydroxyprogesterone.28 Simultaneousoxidation and chlorination by tert.-butyl hypochlorite gave the chloro-ketone (XLI). The 3 : 20-di(ethylene ketal) of this was reduced (lithiumaluminium hydride) to the 11p-01, which was hydrolysed selectively to themonoketal (XLII). Introduction of a 21-acetoxy-group via a 21-bromidewas followed by hydrolysis of the remaining ketal group; the 4-chloro-ketone then gave cortisol acetate (XLIII ; R = Ac) by the successive actionof semi-carbazide and pyruvic acid.COMe COhfe1 c1 (XLI)CO*CH,*OR COMeSeveral - stages(XLIII) (XLII)The organism Rhizopzts arrhizus with some of the above substratesgenerally effected 6P-hydroxylation, with a subsidiary proportion of 1 la-hydroxylati~n.~~? 30, 31 Other microbiological oxidations of interest includethe conversion of substance S (XXXVIII) into cortisol (XLIII; R = H)directly by Cunninghamella bZake~Zeeana.~G Three independent communica-tions 37 described the oxidation of progesterone to androsta-1 : 4-diene-3 : 17-dione (XLIV), and the oxidation of testosterone, progesterone, 17a-35 R.H. Levin, B. J. Magerlein, A. V. McIntosh, A. R. Hanze, G. S. Fonken, J. L.Thompson, A.M. Searcy, M. A. Scheri, and E. S. Gutsell, J .Amer. Chem.Soc., 1953,75,502.36 F. R. Hanson, K. M. Mann, E. D. Nielson, H. V. Anderson, M. P. Brunner, J . N.Karnemaat, D. R. Colingsworth, and W. J. Haines, ibid., p. 5369.37 E. Vischer and A. Wettstein, Experientia, 1953, 9, 371 ; J. Fried, R. W. Thoma,and A. Klingsberg, 1. Amer. Chem. Soc., 1953, 75, 5764; D. H. Peterson, S. H. Eppstein,P. D. Meister, H. C. Murray, H. M. Leigh, A. Weintraub, and L. M. Reineke, ibid.,p. 6768224 ORGANIC CHEMISTRY.hydroxyprogesterone or substance S to “ testololactone ” (XLV) by variousorganisms.0Transformation of substance S (XXXVIII) into cortisol (XLIII ; R = H)by liver homogenates was reported.38Among the chemical methods for introducing an 1 l-oxygen atom, furtherprogress was made with the already highly refined conversion of 7 : 9-dienesinto ll-ketones.Treatment of a 9a : lla-epoxy-7-ene (XLVI) with borontrifluoride in ether gives a 7-en-9p-one (XLVII),399 40 isomerized by aluminasuccessively to the “normal ” 9a-one (XLVIII) and to the 8-en-ll-one(XLIX). The inversion at C(9) without rearrangement of the double bond(XLVII) (XLVIII) (XLIX)COMe(XLVI)is noteworthy and suggests simultaneous removal and addition of a proton.40In the 9p-one (XLVII), ring c has approximately the ‘‘ boat ” conformationand hence the angular methyl groups are farther apart than in the naturalsteroids. This difference is reflected in the ease of hydrogenation of the7 : %double bond in (XLVII) : it can, for example, be hydrogenated withoutreduction of the 22 : 23-double bond in an ergosterol ~ide-chain.~~, 41 Theresulting saturated ketone (L) is isomerized to the *‘ natural ” (9a) configur-ation (LI) by strong alkali.40This procedure was used in a new transformation of ergosterol intocortisone.42 The side-chain in 5 : 6-dihydroergosterol was shortened, advan-tage being taken of the inert nuclear double bond. The resulting ketone(LII) was dehydrogenated to the 7 : 9-diene; then by the above procedurethe 1 l-keto-group.was introduced.The remaining stages are known.38 D. Amelung, H. J. Hiibener, and L. Roka, 2. flhysiol. Chem., 1953, 294, 36.39 K. Heusler and A. Wettstein, Helv. Chim. Acta, 1953, 36, 398.40 P. Bladon, H. B. Henbest, B. J. Lovell, G. W. Wood, G. F. Woods, J. Elks,R. M. Evans, D.E. Hathway, J. S. Oughton, and G. H. Thomas, J., 1953, 2921.*l J. Elks, R. M. Evans, C. H. Robinson, G. H. Thomas, and L. J. Wyman, ibid.,p. 2933.4 2 D. Maclean, W. S. Strachan, and F. S. Spring, Chem. and Ind., 1953, 1259CORNFORTH STEROIDS. 225A series of papers 403 43 described a different approach to the ergosterol __tcortisone problem, the object being to preserve, during the other necessarystructural alterations, a potential 4 : 5-double bond in the form of a 5a-hydr-oxy-group. The technique may be exemplified by a synthesis of ll-oxo-progesterone. Dehydroergosterol epidioxide acetate (LIII) was hydrogen-SeveralstagesSeveral - stagesOH (Lv)CrO,; KOHfated over nickel directly to the 5a-hydroxy-7 : 9-diene (LIV), which isevidently formed by dehydration of an intermediate 8a-01.The 9cc : l l a -epoxide of (LIV) could be degraded, by way of a bisnorcholenal and its enolacetate, to the methyl ketone (LV). The procedure already describedthen gave the 11-ketone (LYI) which was converted into 11-oxoprogesterone(LVII) by chromic acid oxidation and dehydration with alkali.Several papers appeared, which amplified work already briefly reported,on 7 : 9-diene - 11-ketone processes. The Merck group described 44 atechnique for hydrogenating 5 : 7-dienes t o 7-enes over Raney nickel inbenzene, and published a study of the oxidation of 7-enes by mercuricacetate to 7 : g-diene~.~~ Details of later stages were also gi~en.~6 I t is43 P. Bladon, R. B. Clayton, C. W. Greenhalgh, H.B. Henbest, E. R. H. Jones,B. J . Lovell, G. Silverstone, G. W. Wood, and G. F. Woods, J . , 1952, 4553; H. B. Hen-best, E. R. H. Jones, G. W. Wood, and G. F. Woods, ibid., p. 4894; P. Bladon et idem,ibid., p. 4890; R. B. Clayton, A. Crawshaw, H. B. Henbest, E. R. H. Jones, B. J. Lovell,and G. W. Wood, J., 1953, 2009; R. B. Clayton, H. B. Henbest, and E. R. H. Jones,ibid., p. 2015; P. Bladon, H. B. Henbest, E. R. H. Jones, G. W. Wood, D. C. Eaton,and A. A. Wagland, ibid., p. 2916.44 W. V. Ruyle, E. M. Chamberlin, J. 31. Chemerda, G. E. Sita, L. M. Aliminosa,and R. L. Erickson, J . Amer. Chem. Soc., 1952, 74, 5929.4 5 W. V. Ruyle, T. A. Jacob, J. M. Chemerda, E. M. Chamberlin, D. W. Rosenburg,G. E. Sita, R. L. Erickson, L. M. Aliminosa, and M.Tishler, ibid., 1953, 75, 2604.4 6 E. M. Chamberlip, W. V. Ruyle, A. E. Erickson, J. $1. Chemerda, L. &I. Aliminosa,R. L. Erickson, G. E. Sita, and M. Tishler, ibid., p. 3477.REP.-VOL. L 226 ORGANIC CHEMISTRY.interesting that " 22a" : 5p-spirostan-7-en-3a-01 (LVIII) could not be oxidizedto a 7 : 9-diene, unlike corresponding substances in the 5a-~eries.~' Fieserand his collaborators have described various oxidations of 7 : 9-diene~.*~The elegant Ciba49 process for modifying a bile-acid side chain wasfurther improved : 50 when the diphenylcholene (LIX) was treated with twoequivalents of N-bromosuccinimide in allyl bromide, the bromo-diene (LX)was produced smoothly in at least 70% yield; no hydrogen bromide wasevolved, the allyl bromide being partly converted into dibromopropane.Curiously, when the bromo-compound (LXI) was heated in allyl bromide,evolution of free hydrogen bromide accompanied formation of a diene.RrMe II/\//CP1'2/ -- /-A simple conversion of cortisone into cortisol (XLIII; R = H) wasreported.51 Cortisone (but not its 21-acetate, which gave a 3-monoketal)with ethylene glycol gave the 3 : 20-di(ethylene ketal), which was reducedby lithium aluminium hydride to the llp-01 and hydrolysed to cortisol.A new method of transforming 12-oxo-steroids into ll-oxo- or 1 lp-hydr-oxysteroids was found independently in two laboratories ; 52* 53 hecogeninH? Br, C,H,,02BrCC13.C02 1 Me \/\//\/-(LXVII) I y- (LXV)I C II (LXVI)acetate (LXII) was in each case the initial material. The known 11 : 23-dibromohecogenin acetate (LXIII) was reduced by sodium borohydride 52or lithium borohydride 53 to a mixture of the lap- (LXIV) and the 12a-01,47 M.Velasco, J. Rivera, G. Rosenkranz, F. Sondheimer, and C. Djerassi, J . Org.Chem., 1953, 18, 92.48 L. F. Fieser, W.-Y. Huang, and J . C. Babcock, J . Amer. Chem. SOL, 1953, 75, 116;L. F. Fieser and J . E. Herz, ibid., p. 121; L. F. Fieser, W. P. Schneider, and \V.-Y.Huang, ibid., p. 124.49 C. Meystre, H. Frey, A. Wettstein, and K. Miescher, Helv. Chim. Acta, 1944, 27,1815, and later papers.51 R. Antonucci, S. Bernstein, M. Heller, R. Lenhard, R. Littell, and J. H. Williams,J . Org. Chem., 1953, 18, 70.52 J. W. Cornforth and J. M. Osbond, Chem. and. Ind., 1953, 919.53 J.Schmidlin and A. Wettstein, Helv. Chim. Acta, 1953, 36, 1241.50 J: Heer and A. Wettstein, ibid., 1953, 36, 891CORNFORTH : STEROIDS. 227the former predominating. On treatment of (LXIV) with sodium hydr-oxide 52 or silver oxide and pyridine 53 an l l p : 12p-epoxide (LXV) wasiormed (the 12a-01 with these reagents gave a 12-one; cf. refs. 8 and 0).Addition of hydrogen halides to the epoxide then gave a 12a-halogeno-llp-01 (LXVI) which could be changed into an ll-one by oxidation and zincdust reduction, or into an llp-01 by dehalogenation with Raney nickel. Theunreactive bromine atom at C(23) could be removed either a t the final stage 529 53or from the e p ~ x i d e . ~ ~Conversion of an l l a : 12a-epoxide into an l l p : 12p-epoxide, and thenceinto an ll-one, was illustrated in the cholanic acid series.54 The a-epoxidewith trichloroacetic acid gave an 11 p-trichloroacetoxy-l2a-01 (LXVII) ;the methanesulphonate of this underwent, with alkali, a trans-eliminationwhich gave the p-epoxide in 50% overall yield.Imitation of Hormones.-Several " artificial hormones " were found toshow biological activity.The high progestational activity of 19-norpro-gesterone 55 is now paralleled 56 by the mineralocorticoid activity of 19-nor-deoxycorticosterone acetate (LXVIII) : this is apparently about twice aspotent as deoxycorticosterone. " 9 : 11-Anhydrocorticosterone " acetate isalso active,57 and D-homodeoxycorticosterone acetate slightly Weakandrogenic activity was observed in the synthetic product (LXIX),59 but18-nor-D-homoandrostanedione (LXX), a by-product of the total synthesispreviously described, appeared to be as active an androgen, even in the(-+)-form, as androstane-3 : 17-di0ne.~~11 a : 17u : 21-Trihydroxypregn-4-ene-3 : 20-dione (LXXI ; readily avail-able by microbial oxidation of substance s) after acetylation at Ctzl) andtoluene-P-sulphonation at C(lr) was converted (sodium acetate in acetic acid)into the 4 : 9(11)-diene (LXXII) ; the reaction is a &elimination. N-Bromoacetamide then gave the 9a-bromo-1 1 p-hydroxy-compound whichpotassium acetate cyclized to the epoxide (LXXIII).This epoxide reactedwith hydrogen halides to give 9a-halogeno-llp-ols which were oxidized toll-ones (LXXIV). The method can, of course, be used to produce cortisoneor cortisol by dehalogenation of suitable intermediates, but it is interestingthat 9a-chlorocortisone acetate (LXXIV; X = C1) and its precursor, the9a-chloro-11 p-01, proved to have activity greater than that of cortisone itself54 A.Fiirst and R. Scotoni, Helv. Chim. Acta., 1953, 36, 1410.5 5 For details of preparation see C . Djerassi, L. Miramontes, and G. Rosenkranz,5 G A. Sandoval, L. Miramontes, G. Rosenkranz, C. Djerassi, and F. Sondheimer,5 7 R. Casanova, C. W. Shoppee, and G. H. R. Summers, J., 1953, 2983.5 8 R. M. Dodson, P. B. Sollman, and B. Riegel, J . Amer. Chem. SOC., 1953, 75, 6132.59 A. J. Birch and J. A. K. Quartey, Chem. and Ind., 1953, 489.60 W. S. Johnson, H. Lemajre, and R. Pappo, J .Amer. Chem. Soc., 1953, 75, 4866.J . Anzer. Chem. SOC., 1953, 7 5 , 4440.ibzd., p. 4117228 ORGANIC CHEMISTRY.in the rat-liver glycogen assay. 61was attributed to rapid reductionRearrangement Reactions.-Ahexalone (LXXV) showed thatThe activity of the 81-aldehyde of cortisonein vivo to cortisone.62CO*CH,*OAcThree___tstageso&&/' (LXXII)GO*CH,.OAcob\/'d (LXXIII)study of the aromatization of the methyl-aqueous mineral acids gave principaily5 : 6 : 7 : 8ltetrahydro-4-methyl-2-naphthol (LXXVI) whereas anhydrousacids in acetic anhydride favoured the alternative rearrangement to thetetrahydro-1-naphthol (LXXVII). Similar behaviour was observed withandrostan-1 : 4-diene-3 : 17-di0ne.~~ The rearrangement product from chol-estadienone and acetic anhydride-sulphuric acid gave on dehydrogenationwith selenium a hydrocarbon now identified, by synthesis,64 with 8 : 3'-dimethyl-1 : 2-cyclopentenophenanthrene.(LXXVI) (LXXV) (LXXVII)A remarkable and ready aromatization of dehydroergosterol (LXXVIII)was found to occur in chloroform containing a trace of hydrogen chloride.65The product is considered to have the structure (LXXIX) and on oxidationit furnished the methylbenzenetetracarboxylic acid (LXXX) previously(j9H1,pyYy- A?) __tHO/\/\/(LXXVIII)known as an abnormal oxidation product from ergosterol (with nitric acid).The assignment of structure to this acid is fortified by a synthesis 66 of theacid (LXXXI), which proved to be different.61 J.Fried and E.F. Sabo, J . Amer. Ckem. Soc., 1953, 75, 2273.62 J. J. Schneider, ibid., p . 2024.63 A. S. Dreiding, W. J. Pummer, and A. J. Tomasewski, ibid., p . 3159.64 R. B. Woodward, H. H. Inhoffen, H. 0. Larson, and K. H. Menzel, Chem. Bey.,66 K. Alder and B. Kruger, Chem. Ber., 1953, 86, 985.1953, 86, 594. 6 5 W. R. Nes and E. Mosettig, J . Amer. Chenz. SOC., 1953, 75, 2789CORNFORTH : STEROIDS. 229Acetolysis of 6p-bromocholest-4-en-3-one produced Za-acetoxycholest-4-en-3-one (LXXXII),67 the structure of which was proved by degradation(via a mercaptal) to cholestan-Za-01. Similar results were observed in thetestosterone series,68 and the reaction was used to effect a partial synthesisCO,H CO,HCO,H(LXXX) (LXXXI) (LXXXI I)of gitogenin from dio~genin.~~ Two interesting papers appearedstereochemistry of rearrangements among D-homosteroids.70on theReactions of Especial Iderest.-The resistance of an 11 p-hydroxy-groupto acetylation under ordinary conditions is notorious, but when 3a : l l p : 17a-trihydroxypregnan-20-one was treated a t room temperature with aceticacid-acetic anhydride containing perchloric or t oluene-fi-sulphonic acid allthree hydroxyl groups were acetylated. 71 Toluene-fi-sulphonic acid withisopropenyl acetate was also effective. The product could be hydrolysed bysodium carbonate in methanol to an llp-monoacetate, but data on thehydrolysis of the 11 p-acetoxy-group are not yet available.Manganese dioxide, already known in the vitamin A field as a ratherselective oxidizing agent for allylic alcohols, was applied 72 to oxidation ofA4-3p-01s to A4-3-ones ; e.g., testosterone was prepared rather simply fromandrostenedione by reduction with lithium aluminium hydride and selectiveoxidation by manganese dioxide a t room temperature.A4-3p : 6p-Diolswere oxidized t o 6p-hydroxy-h4-3-ones. Cholesterol under more vigorousconditions gave cholesta-4 : 6-dien-3-one ; 72 cholesteryl acetate on the otherhand was oxidized to 7-oxocholesteryl acetate. 73An interesting example of steric effects on the course of hydrogenationwas discovered : 74 efiicholesterol (or its acetate or methyl ether) was hydro-genated over platinum in acidic methanol to efiicoprosterol, addition ofhydrogen thus taking place, abnormally, on the p-side.(LXXXIV) (LXXXI I I) (LXXXV)Sa-Hydroxycholestan-3~-yl toluene-P-sulphonate (LXXXIII) with sod-ium tert.-butoxide gave a mixture of the 3cc : Scc-epoxide (LXXXIV) and the6 7 L.F. Fieser and M. A. Romero, J . Amer. Chem. SOG., 1953, 75, 4716.6 8 F. Sondheimer, S. Kaufmann, J. Romo, H. Martinez, and G. Rosenkranz, ibid.,p. 4712.60 J. Herran, G. Rosenkranz, and F. Sondheimer, Chem. and Ind., 1953, 824.70 R. J. W. Cremlyn, D. L. Garmaise, and C. W. Shoppee, J., 1953, 1847; R. B.Turner, J . Amer. Chem. SOG., 1953, 15, 3484.71 E. P. Oliveto, C. Gerold, and E. B. Hershberg, Arch. Biochem. Biophys., 1953, 43,234; idem with L. Weber, H. E. Jorgensen, and R. Rausser, J . Amer. Chem. SOG., 1953,75, 5486.72 F. Sondheimer and G. Rosenkranz, Experientia, 1953, 9, 62 ; idem and C.Amen-dolla, J . Amer. Chem. SOG., 1953, 75, 5930, 5932.73 P. Meunier, G. Zwingelstein, and J. Jouanneteau, Bull. SOG. Chim. biol., 1953,35, 495. 74 J . R. Lewis and C. W. Shoppee, Chenz. and Ind., 1953, 897230 ORGANIC CHEMISTRY.ketone (LXXXV).75 Studies of the methanolysis of various steroid toluene-fi-sulphonates were reported. 76The7-monoenol acetate of methyl 3a-acetoxy-7 : 12-dioxocholanate was shownto have a 6 : 7-double bond, and a 9 : ll-double bond was demonstrated inthe enol acetate of methyl 3~--acetoxy-ll-oxocholanate.~~ Cholestanoneenol acetate, after reduction with lithium aluminium deuteride, decom-position with water, and reoxidation, gave a cholestanone retaining nodeuterium. Reduction with lithium aluminium hydride, decomposition withdeuterium oxide, and oxidation gave a cholestanone having one atom ofdeuterium.This evidence suggests that a complex such as (LXXXVI), oran intermolecular equivalent, is formed in the reduction of enol acetates, thehydrogen atoms marked (*) being introduced by the reducing agent andthe atom marked ( 7 ) during decomposition by water.78 The action of N-iodosuccinimide on enol acetates was shown to give a-iodo-ketones. Theother product was N-acetylsuccinimide. 79There were several contributions to the chemistry of enol acetates./ItAcO/\LiAlH, -allBiosynthesis of Steroids.-The demonstration that acetic acid can furnishthe carbon atoms required for biosynthesis of cholesterol, and that fifteen(LXXXVI I)MeI- Ag20 1- KOH(KO,C*[CH,],*CH:CH,) 'O,C*[CH,],*CH (CH,) -NMe,+ 1.KOHSee ref. 82 1 s sHO,C-CH, + HO,t$H,-?H, __t to, + HO,??H," methyl " and twelve " carboxyl " carbon atoms are apparently needed,made it of interest to find ways of separating the carbon atoms of cholesterol7 5 R. B. Clayton and H. B. Henbest, Chem. and Ind., 1953, 1315.76 H. R. Nace, J . Amev. Chem. Soc., 1952, 7 4 , 5937; D. D. Evans and C. W. Shoppee,7 7 R. Hirschmann and N. L. Wendler, J - Amer. Chem. SOL, 1953,75,2361.78 W. G. Dauben and J. F. Eastham, ibid., p. 1718.79 C. Djerassi and C. T. Lenk, ibid., p. 3493.8 0 H. N. Little and K. Bloch, J . Biol. Chem., 1950, 183, 33.J., 1953,540CORNFORTH STEROIDS. 231biosynthesized from " labelled " [14C]acetic acid, in order to trace theorigin of individual carbon atoms.A new degradation of cholesterol *lmade possible the separation of eight carbon atoms from rings A and B.The decisive stage in this process was a pyrolysis of the keto-aldehyde(LXXXVII), obtained from cholest-5-ene by a manipulation of ring B whichalso separated c(6) as carbon dioxide, to 2-methylcyclohexanone. Thisketone, containing the carbon atoms of ring A, was degraded as shown tothree molecules of acetic acid and one of carbon dioxide; the carbon atomsof acetic acid were separated by well-established methods.In this way it was shown that carbon atoms 2, 4, 6, and 10 are derivedfrom acetate-carboxyl, and carbon atoms 1, 3, 5, and 19 from acetate-methyl. Previously,= the side-chain of cholesterol had been separated intoits constituent carbon atoms by adapting classical procedures.Carbonatoms, 25, 23, and 20 were identified as " carboxyl "-carbon, and 26, 27,24, 22, and 21 as " methyl "-carbon,Evidence that the terpenoid hydrocarbon squalene is a precursor ofcholesterol in vivo was mentioned in last year's Report (p. 201). Sir RobertRobinson's original suggestion 84 of a hypothetical cyclization of squaleneto cholesterol would give a distribution (if the construction of squalene fromacetate is assumed t o proceed as suggested for another terpenoid compound,the guayule rubber hydrocarbon 85) of " carboxy1"- and " methyl "-carbonLanosterolCholesterol6 and'' m " signifies " methyl "-carbon ; " c '' signifies " carboxyl "-carbon.as shown in (LXXXVIII). This agrees with the results of the two degrad-ations mentioned above.However, Woodward and Bloch,S6 impressed bythe close analogy between lanosterol and cholesterol, postulated another81 J. 14'. Cornforth, G. D. Hunter, and G. Popjiik, Biochem. J . , 1953, 54, 590, 597.a2 G. D. Hunter and G. PopjBk, ibid., 1951, 50, 163.83 J . Wursch, R. L. Huang, and K. Bloch, J . Biol. Chem., 1952, 185, 439.84 R. Robinson, J , SOC. Chem. Ind., 1934, 53, 1062.8 5 J. Bonner and B. Arreguin, Arch. Biochem., 1949, 21, 109.8 6 R. B. Woodward and K. Bloch, J . Amzer. Chem. SOC., 1953, 75, 2023232 ORGANIC CHEMISTRY.mode of cyclization involving migration of a methyl group. This gives apattern (LXXXIX) identical with (LXXXVIII) in the parts already knownbut differing elsewhere.Oxidation of a labelled androstane-3 : 17-diol bythe Kuhn-Roth method and examination of the carboxyl-carbon of theresulting acetic acid (this carbon originates from positions 10 and 13, andto be a " carboxyl "-carbon) now showed that carbon atom13 is a "methyl"-carbon, in harmony with the new hypothesis but notwith the old. Later, Bloch 87 separated carbon atom 7 of cholesterol. Thisproved to be a " methyl "-carbon, again supporting the new hypothesis.It was observed that (' squalene " regenerated from the hexahydro-chloride was not incorporated into cholesterol in vivo; however, the infra-red spectrum after regeneration is different and the product may not contain" natural " squalene.88$ s9published a series ofpapers dealing with the chromic acid oxidation of cholesterol and with theimpurities present in the commercial sterol.Cholestanol and lathosterol(cholest-7-en-3p-01) are common impurities ; so also is an unknown substance,isolated as a ketone C27H4403 (" ketone 104 ") after oxidation.Space is not available to review numerous papers on the isolation andchemistry of cardiac glycosides; the story here4-f is one of steady progress along established lines.\-/ The structure of scilliglaucosidin, a highly potentglycoside of squill, was elucidated : 91 the aglyconehas the structure (XC). The orientation of thehydroxyl groups in digoxigenin has been deter-mined by degradation to methyl 3 p : 12p-dihydroxy-etianate.92species was named markogenin, after R.E. Marker. It is " 22b "-spirostan-26 : 3p-di01.~~Identification of Steroids.-The absorption spectra of 220 steroids inconcentrated sulphuric acid under standard conditions were listed.94 Auseful study was made of steroid 2 : 4-dinitrophenylhydra~ones.~~ Papersappeared on the infra-red spectra of ~apogenins,~~ e p o x i d e ~ , ~ ~ chole~tenols,~~and other steroidsg9is knownNatural Steroids-Fieser and his collaboratorsItel-A new sapogenin from several YuccaJ. W. C.8 7 K. Bloch, Helv. Chim. Acta, 1953, 36, 1611.8 8 R. G. Langdon and K. Bloch, J . Biol. Chem., 1953, 200, 135.89 G. M. Tomkins, W. G. Dauben, H. Sheppard, and I. L. Chaikoff, ibid., 1953, 202,487, and earlier papers.90 L.F. Fieser, J . Amer. Chem. Soc., 1953, '75, 4377, 4386, 4395; L. F. Fieser andG. Ourisson, ibid., p. 4404; L. F, Fieser and B. K. Bhattacharyya, ibid., p. 4418;K. Nakanishi, B. K. Bhattacharyya, and L. F. Fieser, ibid., p. 4415.91 A. Stoll, A. von Wartburg, and J. Renz, Helv. Chim. Acta, 1953, 36, 1531.92 S. Pataki, K. Meyer, and T. Reichstein, ibid., p. 1295.93 M. E. Wall, C . R. Eddy, S. Serota, and R. F. Minigef, J . Amer. Chenz. Soc., 1953,94 S. Bernstein and R. Lenhard, J . Org. Chem., 1953, 18, 1146.95 H. Reich, K. F. Crane, and S. J. Sanfilippo, ibid., p. 822.9 6 C . R. Eddy, M. E. Wall, and M. K. Scott, AnaZyt. Chem., 1953, 25, 266; R. N.Jones, E. Katzenellenbogen, and K. Dobriner, J . Amer. Chem. Soc., 1953, 75, 168.9 7 H. H. Gunthard, H. Heusser.and A. Furst, Helv. Chim. A d a , 1953, 36, 1900.98 D. R. Johnson, D. R. Idler, V. W. Meloche, and C. A. Baumann, J . Amer. Chem.Soc., 1953, 75, 52.75, 4437.Q9 H. Rosenkrantz and L. Zablow, ibid., p. 903WALKER : HETEROCYCLIC COMPOUNDS. 2337. HETEROCYCLIC COMPOUNDS.Small Rings.-Unstable intermediates obtained in the Neber rearrange-ment 1 of oximes to a-amino-ketones are shown to be azirines, e g . , ( I ) ;reduction with lithium aluminium hydride gives the aziridine ; catalyticreduction of, e.g., (I) yields an acetylated propenylamine in the presence ofacetic anhydride and the arylacetone in the presence of water.2 2 : 2-Di-methyl-3 : 3-diphenylethylenimine has been obtained by the action ofphenylmagnesium bromide or phenyl-lithium on isobutyrophenone ~ x i r n e .~The epoxidation of ethylenic compounds with organic peracids has beenreviewed,4 and continued studies of the fission of the oxiran ring by avariety of reagents are reported.5 The ready formation of episulphidesfrom epoxides and thiourea and thiocyanates is clearly shown to involvetwo Walden inversions by the observation that D(+)-2 : 3-epoxybutaneaffords L( -)-2 : 3-epithiobutane. Trimethylene sulphide (thiacyclobutane),for which physical properties suggest a planar structure,8 affords a stablesulphone with hydrogen peroxide in contrast with propylene sulphide whichgives 2-hydroxypropane-l-sulphonic acid,s but, like the latter, it undergoescleavage with chlorine, giving bis-3-chloropropyl disulphide, the relatedsulphenyl chloride, or the sulphonyl chloride depending upon the amountof halogen used.lO A convenient synthesis of 1 : 3-epoxybutane has beendescribed.llFive-membered Ring Systems.-Vinylene carbonate (1 : 3-dioxol-2-one)(11), possibly the first example of a cyclic carbonate of an enediol, is obtainedby dehydrochlorination of chloroethylene carbonate, and acts as a dienophiletowards 2 : 3-dimethylbutadiene to give the cyclic carbonate of 4 : 5-di-methylcyclohex-4-ene-cis-1 : 2-dio1.12A new method for the synthesis of substituted pyrroles is basedon the Michael-type addition of N-substituted p-aminocrotonic esters tol-nitropropene, which leads directly to N-substituted ethyl 2 : 4-dimethyl-pyrrole-3-carboxylates in good yield ; the reaction involves a novel nucleo-philic displacement of nitrite ion and its subsequent use for dehydrogen-ation. l3Anomalous displacements have been observed in applying the Gatter-mann hydrogen cyanide-hydrogen chloride formylation method to 2-bromo-Pyrrole.1 P.W. Neber and A. Burgard, Annalen, 1932, 493, 281 ; P. W. Neber and G. Huh,ibid., 1935, 515, 283.2 D. J. Cram and M. J. Hatch, J . Amer. Chem. SOC., 1953, 75, 33; M. J. Hatch andD. J. Cram, ibid., p. 38.3 H. M. Kissman, D. S. Tarbell, and J. Williams, ibid., p. 2959; cf. K. N. Campbell,B. K. Campbell, J. F. McKenna, and E. P. Chaput, J . Org. Chem., 1943, 8, 103.4 D Swern, Org. Reactions, 1953, 7, 378.G. D. Zuidema, P. L. Cook, and G. VanZyl, J . Anzer. Chem. Soc., 1953, '95, 294-R.T. E. Schenck and S. Kaizerman, ibid., p. 1636; C. 0. Guss, R. Rosenthal, and R. I;.:Brown, ibid., p. 2393; N. R. Easton and V. B. Fish, J . Org. Chem., 1953, 18, 1071.6 F. G. Bordwell and H. M. Andersen, J . Amer. Chenz. SOC., 1953, 75, 4959.7 C. C. Price and P. F. Kirk, ibid., p. 2396.8 D. W. Scott, H. L. Finke, W. N. Hubbard, J. P. McCullough, C. Katz, M. E. Gross,Q J. M. Stewart and H. P. Cordts, ibid., 1952, 74, 5880.10 J. M. Stewart and C. H. Burnside, ibid., 1953, 75, 243.11 F. Sondheimer and R. B. Woodward, ibid., p. 5438.12 M. S. Newman and R. W. Addor, ibid., p. 1263.l3 C. A. Grob and K. Camenisch, Helv. Chim. Acta, 1953, 36, 49.J. F. Messerly, R. E. Pennington, and G. Waddington, ibid., p. 2795234 ORGANIC CHEMISTRY.4-et hoxycarbonyl-3-methylpyrrole, l4 as 2-chloro-4-ethoxycarbonyl-5-formyl-3-methylpyrrole was obtained along with 5-chloro-4-ethoxycarbonyl-2-formyl-3-methyl- and 4-ethoxycarbonyl-2-formyl-3-methyl-pyrrole.1~ Al-though an electron-attracting group in the ct-position of a pyrrole preventssubstitution in an adjacent free p-position by the Gattermann-Hoeschreaction,16 such a pyrrole can still take part in a Mannich reaction; l7 thelatter reaction also affords ready access to 2--2'-pyrrolylethylamine fromEt0,C- Me "ieYpyrrole by way of 2-cyanomethylpyrr01e.~~ The ultra-violet absorptionspectra of negatively substituted pyrroles are strongly dependent on theposition of the electron-attracting group(s) and have been used in the revisionof previously accepted structure^.^^ Light-absorption characteristics suggestthat 3-hydroxypyrroles exist in the oxopyrroline as do also 2-hydroxy-p yrroles .2Outstanding advances have been made in our knowledge of the biogenesisof porphyrins.Porphobilinogen, a labile substance present in porphyriaurines, has been crystallised 22 and shown conclusively to be the monocyclicpyrrole (111),239 24 which passes on mild treatment with acid into a porphyrinmixture Z3l 25 containing mainly uroporphyrin I11 (IV),23 and on treatmentwith haemolysed chicken red cells into proto-, copro-, and uro-porphyrin.26It has been known for some time that the protoporphyrin molecule is deriv-able from eight molecules of glycine and eight molecules of " active " suc-cinate, and the observation that 6-aminolaevulic acid (V) can replace boththese precursors 27 provides a simple and logical precursor of (111), as hasbeen demonstrated in vitro in the presence of hzemolysed chicken red cells.28The biosynthesis of chlorophyll has also been reviewed.29Carbonyl groups in the 3-position of steroids react preferentially with1 4 G.G. Kleinspehn and A. H. Corwin, J . Amer. Chem. SOC., 1953, 75, 5295.1 5 A. H. Corwin and G. G. Kleinspehn, ibid., p. 2089.16 S. F. MacDonald, .f., 1952, 4176.1 7 A. Treibs and W. Ott, Naturwiss., 1953, 40, 476.18 W. Herz. J . Amer. Chem. SOC., 1953, 75, 483.19 G. H. Cookson, J., 1953, 2789.21 C. A. Grob and P. Ankli, Helv. Chivtz. Acta, 1949, 32, 2010.22 R. G. Westall, Nature, 1952, 170, 614.23 G.H. Cookson and C. Rimington, Nature, 1953, 171, 875.24 0. Kennard. ibid., p. 876; G. H. Cookson, ibid., 1953, 112, 457; S. Granick and25 P. E. Brockman and C. H. Gray, Biochem. J . , 1953, 54, 22.2 6 J . E. Falk, E. I. B. Dresel, and C . Rimington, Nature, 1953, 172, 292.27 D. Shemin and C. S. Russell, J . Amer. Chem. SOC., 1953, 75, 4873: A. Neubergerand J. J. Scott, Nature, 1953, 172, 1093.28 E. I. B. Dresel and J. E. Falk, ibid., p. 1185.20 K. Egle, Naturwiss., 1953, 40, 569.2o J. Davoll, J., 1953, 3805.L. Bogorad, J . Amer. Chem. SOC., 1953, 75, 3610WALKER : HETEROCYCLIC COMPOUNDS. 235pyrrolidine to give the 3-(pyrrolidino)enamines, thus offering a useful methodfor the protection of 3-keto-groups during, for example, lithium aluminiumhydride reduction of other carbonyl groups in the molecule.30/co NH,*CH, NH,A P1-1A- --A A- _I,Fuuran.The stereochemistry of the furan-maleic anhydride reactioncontinues to receive a t t e n t i ~ n , ~ ~ and two stereospecific syntheses of canthar-idin (VI) have been described. In the first,32 dimethyl 3 : 6-epoxy-3 : 4 : 5 : 6-tetrahydrophthalate (VII) was condensed with butadiene to give the adduct(VIII), in which the two methoxycarbonyl groups were then converted intomethyl groups and the cyclohexene ring ultimately provided the dicarboxylicanhydride ring of (VI). In the second synthesis,33 1 : 2-dihydro-1 : 2-di-methylphthalic anhydride (IX) gave in over 50% yield a peroxide (X)having the peroxide bridge in the &-position to the anhydride ring.Cata-lytic reduction gave the saturated dihydroxy-compound (XI), and thence30 F. W. Heyl and M. E. Herr, J . Amev. Chem. SOL, 1953, 75, 1918; M. E. Herr and32 G. Stork, E. E. van Tamelen. L. J. Friedman, and A. W. Burgstahler, ibid., p. 384.33 G. 0. Schenck and R. Wirtz, Naturwiss., 1953, 40, 581.F. W. Heyl, ibid.. p. 5927. 31 J. A. Berson and R. Swidler, ibid., p. 1721236 ORGANIC CHEMISTRY.the lactone (XII), Gadamer’s hydrobromocantharic acid (XIII),34 andcantharidin (VI).Synthetic applications of furans include the widely applicable conversionof 2-f uryl ketones with ammonia into 2-subs t i t ut ed 3-hydro~ypyridines,~the conversion of 2-methylfuran by a four-stage process into the thiazolefragment (4-met hyl-5-2‘-hydroxyet h ylt hiazole) of vitamin B and thehydrolysis of difurfurylideneacetone to 4 : 7 : 10-trioxobrassylic acid ; 37a large number of miscellaneous reactions of furans has also been described.38Pyrolysis of 6-dimethylamino-4 : 4-diphenylheptan-3-one methiodide affords2-et hylidene-5-met hyl-3 : 3-diphen yltet rah ydro fThiopken.Thiophens are not readily oxidised to sulphones but oxidationin suitable cases can be effected with perbenzoic acid. In the case of thiophenitself the sulphone is accessible only indirectly; it is a very reactive sub-stance, combining with maleic anhydride and readily trimerising with lossof sulphur dioxide.40 The substance previously described as thiophensulphone is really a sesquioxide (XIV) produced by diene addition of theintermediate sulphoxide to the sulphone; (XIVa) is preferred to (XIVb) asBr, Br Br -2HBr ’\I __t IT,l * I l l 1 + \ /SO, SO, SO,l l ~ ~ l ~ ~ l l or !I /=ir”’ II JI IrAyI ’I\ ITfi),so \so, so, so2 so,(XIVa) (XIVb)the substance is stable towards excess of oxidising agent.40 In the vapour-phase bromination of thiophen the monobromo-product changes from 2- to3-bromothiophen as the temperature rises, but chlorination proceeds lessreadily ; 41 fluorination of thiophen has also been studied.42A number of ring-closures on to the thiophen ring have been reported.Cyclisation of 3-thienylthioacetic acid (XV) with sulphuric acid, followed byreduction of the product with lithium aluminium hydride, gave the solidthiophthen (XVI), which is obtained from acetylene and boiling sulphur.43Thieno(2,3-c)pyridine (XVII) and thieno(3,2-c)pyridine (XVIII) are obtainedby the Pomeranz-Frisch synthesis from thiophen-2- and -3-aldehyde byusing polyphosphoric acid, and the corresponding benzo-derivatives aresimilarly accessible from thianaphthen-2- and -3-aldehyde ; 44 the Bischler-34 J.Gadamer, Arch. Pharln., 1914, 252, 636.35 H. Leditschke, Chew Ber., 1952, 85, 202; 1953, 86, 123, 612; W. Gruber, Canad.J . Chem., 1953, 31, 564.36 T. E. Londergan, N. L. Hause, and W. R. Schmitz, J . Amer. Chem. Soc., 1953, 75,445 6.38 0. Moldenhauer, G. Trautmann. W. Irion, R. Pfluger, H. Doser, D. Mastaglio, and€3. Marwitz, Annalen, 1953, 580, 169; 1953, 583, 37.39 N. R. Easton, S. J. Nelson, V.B. Fish, and P. N. Craig, J . Amer. Chem. SOC., 1953,75, 3751.4 1 C. D. Hurd and H. J. Anderson, J . Amer. Chem. SOC., 1953, 76, 3617.4 2 J. Neudorffer, Ann. Chim., 1953, 8, 501.a3 F. Challenger and J. L. Holmes, J., 1953, 1837.44 W. Herz and L. Tsai, J . Amer. Chem. Soc., 1953, 75, 5122.37 H. Midorikawa, Bull. Chem. SOC. JapaN, 1953, 86, 317.40 J . L. Melles and H. J. Backer, Rec. Trav. chim., 1953, 72, 314, 491WALKER : HETEROCYCLIC COMPOUNDS. 237Napieralski reaction is also a p p l i ~ a b l e , ~ ~ and 4 : 5 : 6 : 7-tetrahydro-4-0~0-thionaphthen (XIX) results from cyclisation of p-2-thienylbutyric acid.46GZyo~aZine.~~ It is becoming increasingly evident that 4-aminoglyoxaline-5-carboxyamide occurs as a riboside or ribotide and that these pentosederivatives are important intermediates in the biosynthesis of purines andtheir derivative^.^^ New, naturally occurring glyoxalines accumulated bymutants of Neurospora and PeniciZZium have been shown to be 4-(trihydroxy-propy1)-, 4-(3-hydroxy-2-oxopropyl)-, 4 ( 2 : 3-dihydroxypropy1)-, and ~-4-(2-amino-3-hydroxypropy1)-glyoxaline (L-histidinol) ; two other products,which appear to be phosphate esters of the trihydroxy- and hydroxyketo-compounds, are considered to be directly involved in the biosynthesis ofh i ~ t i d i n e .~ ~ A physiologically interesting base, murexine, isolated fromMurex trunculus, has been shown to be 0-4-glyoxalinylacryloylcholine(urocanylcholine) (XX) . Formamide reacts with a-hydroxy-, a-halogeno-,a-amino-, and, under reducing conditions, also with a-hydroxyimino-ketonesto give 4 : 5-substituted gly~xalines,~~ which are also obtained in excellentyield from oxazoles and f ~ r m a m i d e .~ ~2-Thiazolylmagnesium bromides are obtained from thiazoleswith a free 2-position and ethylmagnesium bromide and can be used synthetic-ally, acetic anhydride, for example, affording the 2-acetyl derivatives ; 53similarly, phenyl-lithium gives, for example, 2-thiazolyl-lithium, which canbe carboxylated although it is only stable below -40°.54 5 : 5’-Dithiazolylhas been prepared by benzidine transformation of 2-hydrazothiazole inpresence of phthalic anhydride, hydrolysis to the free amine (2 : 2’-diamino-5 : 5’-dithiazolyl), diazotisation, and treatment of the diazo-compound withhypophosphorous acid.55 Ring-closure of the penicillamine derivative (XXI) ,which cannot azlactonise, with thionyl chloride has given the substance(XXII), showing the characteristic infra-red absorption of a p-lactamcarbonyl group but lacking the biological activity of penicillin.56 Recentapplications of mixed anhydrides for the synthesis of peptides 57 haveled to the preparation of benzylpenicillinic ethoxyformic anhydride (XXIII)Thiazole.45 D. B. Capps and C. S. Hamilton, J . Amer. Chem. SOC., 1953, 75, 697.4 6 M. C. Kloetzel, J. E. Little, and D. M. Frisch, J . Org. Chem., 1953, 18, 1511.47 “ Imidazole and its Derivatives. Part I.” by K. Hofmann, Intersci. Publ., New4 8 J. S. Gots, Nature, 1953, 172, 256.49 B. N. Ames, H.K. Mitchell, and M. B. Mitchell, J . Anzer. Chem. Soc., 1953, ‘95, 1016.50 V. Erspamer and 0. Benati, Biochenz. Z., 1953, 324, 66.5 1 H. Bredereck and G. Theilig, Chem. B e y . , 1953, 86, 88. 52 G. Theilig, ibid., p. 96.53 J , Metzger and B. Koether, Bull. SOC. d i m . , 1953, 702. 64 Idem, ibid., p. 708.5 5 M. Erne, L. Herzfeld, B. Prijs, and H. Erlenmeyer, Helv. Chim. Acta, 1953, 36 354.5 6 J. C. Sheehan, K. R. Henery-Logan, and D. A. Johnson, J . Amer. Chem.’Soc.,York, 1953.1953. 76, 3292. Ann. Reports, 1951, 48, 163; 1952, 49, 146238 ORGANIC CHEMISTRY.from which new derivatives of penicillin are acces~ible.5~ A novel type ofpenicillin has been isolated in which the phenylacetyl group of benzyl-penicillin has been replaced by one derived from D-a-aminoadipic acid.59(XXI) (XXI I)-?Me2c11H1002N2s{ <H*CO.OCO.OEt (XXIII)Keten and N-acetylcysteamine gave, besides NS-diacetylcysteamine, asubstance believed to be the enolic form of 2-acetonyl-A2-thiazoline (XXIV)and a substance considered to be (XXV).60 2-Thiothiazolidones are obtainedby an improved technique from ethyleneimines and carbon disulphide,61 anda full account has been given of the degradation and synthesis of actithiazicacid [ (-)-2-(5-carboxypentyl)thiazolid-4-one].62Miscellaneous Jive-membered ring compounds.The isolation and char-acterisation of a-lipoic acid,63 the interrelations of the lipoic a~ids,~4 and thesynthesis of (&)-a-lipoic acid (the cyclic disulphide from 4 : 8-, 5 : 8-, or6 : 8-dimercapto-octanoic acid) 65 have been described.The combined f o m ,for which biological and chemical evidence suggests structure (XXVI),66 isconcerned in the enzymic oxidative decarboxylation of pyruvate.67The equilibrium between 5-amino-l-aryl-1 : 2 : 3-triazoles (XXVII ;R = Aryl, X = CR') and 5-arylamino-1 : 2 : 3-triazoles (XXVIII; R=Aryl, X = CR') has been discussed,68 and is formally analogous to theisomerisation of 5-aminotetrazoles, recalling also the alkali-cat alysed con-version of 4 : 6-diamino-l-P-chlorophenyl-1 : 2-dihydro-2 : 2-dimethyl-1 : 3 : 5-triazine into 6-amino-4-~-chloroanilino-l : 2-dihydro-2 : 2-dimethyl-1 : 3 : 5-triazine.69 5-Aminotetrazoles substituted in the amino-group (XXVIII ;X = N) are formed by cyclisation of appropriate guanylazides but theprincipal products are the l-substituted 5-aminotetrazoles (XXVII ; X =N),70 which are also obtained from monosubstituted cyanamides and hydr-5 8 D.A. Johnson, J . Amer. Chem. SOC., 1953, 75, 3636; R. L. Barnden, R. hl. Evans,J . C. Hamlet, B. A. Hems, A. B. A. Jansen, M. E. Trevett, and G. B. Webb, J., 1953,3733. 59 G. G. F. Newton and E. P. Abraham, Nature, 1953, 172, 395.60 R. Kuhn, G. Quadbeck, and E. Rohm, Chem. Ber., 1953, 86, 468.61 L. B. Clapp and J. W. Watjen, J - Amer. Chem. SOC., 1953, 75, 1490.62 Ann. Reports, 1952, 49, 210; W. M. McLamore, W. D. Celmer, V. V. Bogert,F. C. Pennington, B. A. Sobin, and I. A. Solomons, J . Amer. Chem. SOC., 1953, 75, 105;F. C. Pennington, W. D. Celmer, W. M. McLamore, V. V. Bogert, and I.A. Solomons,6; Ann. Repovts, 1952, 49, 209; L. J. Reed, I. C. Gunsalus, G. H. F. Schnakenberg,Q. F. Soper, H. E. Boaz, S. F. Kern, and T. V. Parke, J . Amer. Chem. SOC., 1953, 75,1267.64 L. J. Reed, B. G. DeBusk, C. S. Hornberger, and I. C . Gunsalus, ibid., p. 1271.65 C. S. Hornberger, R. F. Heitmiller, I. C. Gunsalus, G. H. F. Schnakenberg, and6 6 L. J . Reed and B. G. DeBusk, J . Biol. Chem., 1952, 199, 873, 881.67 Idem, J . Amer. Chem. SOC., 1953, 75, 1261.6 8 B. €2. Brown, D. L1. Hammick, and S. G. Heritage, J., 195.3, 3820.69 H. C . Carrington, A. F. Crowther, D. G. Davey, A. A. Levi, and F. L. Rose, Nature,i o W. G. Finnegan, R. A. Henry, and E. Lieber, J . Org. Chem., 1953, 18, 779.ibid p. 109.L. J. Reed, zbzd., p. 1273.1951, 168, 1080WALKER HETEROCYCLIC COMPOUNDS.239azoic acid.71 When heated, all 5-alkylaminotetrazoles (XXVIII ; R =Alkyl, X = N) rearrange to l-substituted 5-amino-compounds (XXVII ;R = Alkyl, X = N), but, on the other hand, the reverse change occurswhen R is ~henyl,~Ot 72 and 5-alkylamino-l-phenyltetrazoles give 1-a11;yl-5-/CH-CO\Me. N-CH,C\CH-C/ I\S-CH, (XXV)[X = -PO(OH), or-PO(OH)*O*PO(OH),;HSix-membered Ring Systems.-Pyridine. 2 : 6-Di-tert.-butylpyridine isan interesting base which forms salts with protonic acids but does not com-bine with Lewis acids, such as boron trifluoride, because of the bulky sub-stituents ; for the same reason it undergoes smooth nuclear sulphoiiationwith sulphur trioxide in sulphur dioxide while pyridine and 2 : 6-lutidinegive sulphur trioxide addition products.73 The N-oxides of pyridine deriv-atives offer possibilities for substitution by electrophilic reagents that arenot generally appreciated and a good account has been given of recentJapanese work in this field.74 Nitration of 3 : lj-dibrorno-, like that of3-bromo- and 3-ethoxy-, pyridine oxide gives the 4-nitro-compound but3 : 5-diethoxypyridine oxide undergoes nitration in the 2-position.75 De-carbonylation of a-pyridil takes place on heating with lead oxide, givingdi-2-pyridyl ketone, 76 and the related a-pyridoin exists in neutral and faintlyacid solution as the pure enediol (XXIX).77The electron density in crystals of 2-pyridone has been measured withsufficient accuracy in two projections to establish the existence of the -,.- /NMe 'N*CH2??h\l.J(XXXI)molecule in the pyridone form; the pyridine ring departs considerably froma regular hexagonal shape but it is planar within experimental e~~0r.787 1 W.L. Garbrecht and R. M. Herbst, J. Org. Chem., 1953, 18, 1003, 1014, 1022.72 Idem, ibid., p. 1269; cf. also R. M. Herbst and W. L. Garbrecht, ibid., p. 1283.7 3 H. C. Brown and B. Kanner, J . Amer. Chem. Soc., 1953, 75, 3865.74 E. Ochiai, J. Org. Chem., 1953, 18, 534; C. C. J. Culvenor (Reviews Pure Appl.7 5 H. J. DenHertog, C. H. Henkens, and K. Dilz, Rec. Trav. chim., 1953, 72, 296.7 8 W. Mathes and W. Sauermilch, Chem. Ber., 1953, 86, 109.7 7 F. Cramer and W. Krum, ibid., p. 1586; W. Luttke and H. Marsen, 2.Elektro-7 8 B. R. Penfold, Acta Cryst., 1953, 0, 591 ; 2-thiopyridone, idem, ibid., p. 707.Chem., 1953, 3, 83) also gives a useful account of amine oxides.chew., 1953, 57, 680; H. Hensel, Angew. Chem., 1953, 65, 491240 ORGANIC CHEMISTRY,Reduction of 2-n-butyl-3-methylpyridine gives predominantly oneracemic 2-rt-butyl-3-methylpiperidine with sodium and ethanol, and theother racemate on hydrogenation over nickel ; from the relatively greaterease of dehydrogenation of the latter it is believed to be the cis-, and theformer the trans-form. 79 Dimethyl scopolinate (XXX) has been convertedinto 3-benzyl-9-methyl-3 : 9-diazabicycZo[3 : 3 : llnonane (XXXI) by way ofthe benzylimide and reduction with lithium aluminium hydride.sOSpectrophotometric confirmation has been provided forformulating potentially tautomeric aminopyrimidines as the amino- and notas the iminodihydro-forms,sl and attention has been directed to the con-venient synthesis of 5-nitroso- and thence of 5-amino-pyrimidines by con-densation of appropriate hydroxyimino-compounds, e g ., (XXXII), withPyrimidiize.suitable N-C-N components.82 A novel route to pyrimidine derivatives isexemplified by the formation, via N-p-aminocinnamoylacetamide, of 4-hydr-oxy-2-methyl-6-phenylpyrimidine (XXXIV) on catalytic hydrogenation of5-acetamido-3-phenylisooxazole (XXXIII) .83 Many pyrimidine derivativesform crystalline complexes with urea, thiourea, biuret, and di~yandiarnide,~~and many pyrimidine and purine derivatives, including naturally-occurringones, may be characterised by the melting points of eutectics formed withdicyandiamide.85In a revision of earlier work, products formed in the condensation ofalloxan with o-dimethylaminoaniline have been shown to be the spiran(XXXV), formed in an unusual ring-closure involving an N-methyl group,and a substance formed by linking of two molecules of (XXXV) through theposition indicated * by an ether linkage.86 Dealkylation of 5 : 5-dialkyl-barbituric acids has been observed in concentrated sulphuric acid, and thegroup extruded as a carbonium ion may, in the case of 5 : 5-dialkyl-2-thio-barbituric acids, effect alkylation of a 2-thio-group.87 Vicine, long thoughtto be a glucoside of 2 : 5-diamino-4 : 6-dihydroxypyrimidine, is really derivedfrom 2 : 4-diamino-5 : 6-dihydroxypyrimidine, which is the structure ofdivicine, and vicine is the 5-~-~-glucopyranoside.~~ A new antibiotic,79 N.J. Leonard and B. L. Ryder, J . Org. Chew., 1953, 18, 598.80 R. A. Barnes and H. M. Fales, J . Amer. Chem. Soc., 1953, 75, 975; B. H. Chaseand A. M. Downes (J., 1953, 3874) report an analogous piperazine synthesis.81 D. J . Brown and L. N. Short, J., 1953, 331.82 P. D. Landauer and H. N. Rydon, ibid., p. 3721.83 G. Shaw and G. Sugowdz, hrature, 1963, 172, 955.84 S. Birtwell, J . , 1953, 1725.8 5 K. Dimroth and H.-G. Meyer-Brunot, Biochem. Z . , 1952, 323, 343.8 6 F. E. King and J. W. Clark-Lewis, J., 1951, 3379; 1953, 172.E. W. Maynert and E. Washburn, J . Anzer. Chem. Soc., 1963, 75, 700.88 A.3endich and G. C. Clements, Biochim. Biofihys. A d a , 1953, 12, 462WALKER HETEROCYCLIC COMPOUNDS. 241ami~etin,*~ has been found to contain combined cytosine, as well as p-amino-benzoic acid and (+)-a-methyl~erine.~~Few monosubstituted triazines are known and two methodsfor the preparation of 2-phenyl-1 : 3 : 5-triazine have been de~cribed,~~ oneof which involves replacement of chlorine atoms in 4 : 6-dichloro-2-phenyl-1 : 3 : 5-triazine by methylthio-groups followed by Raney nickel desulphur-isation; it is noteworthy that an attempt to effect partial replacement ofchlorine atoms in cyanuric chloride by reduction with lithium aluminiumhydride gave 4 : 6-dichloro-2-dimethylamino-1 : 3 : 5-triazine as the soleproduct.92 Monosubstituted isocyanurates are obtained by condensation ofmono-N-substituted biurets and ethyl carbonate.93Condensed Ring Systems.-Indole.Recalling the behaviour of p y r r o l e ~ , ~ ~indole-3-aldehyde and -3-carboxylic acid and ethyl indole-3-carboxylate arereduced to skatole by lithium aluminium hydride and not to the hydroxy-methyl compound.95 Reaction of 1 : 3-dimethylindole with hexane-2 : 5-&one occurs at the p-position and the resulting indolenine (XXXVI) under-goes cyclisation in the a-position with an appropriately situated activatedmethylene group, to give (XXXVII) ; with heptane-2 : 6-dione, however,the product was the same as obtainable from 3-methylcyclohex-2-enone andwas obviously (XXXVIII) ,96Triazine.CMe-OH ob‘f:~H2 Me-OH ~ ~ $ ~ ~ ~ ~ ~ C O M / \Me H,.COMec1 w(XXXVI) (XXXVII) (XXXVIII) CH5 : 6-Dimethoxyindole is conveniently obtained by catalytic reductionof 3 : 4-dimethoxy-6 : p-dinitrostyrene and it has been converted into therelated harman (XXXIX; R = Me) and yobyrone (XXXIX; R = o-toluoyl) .97 Harman itself has been synthesised starting from the pyridinering by applying the Fischer indole synthesis to cyclohexanone 2-methyl-3-pyridylhydrazone, possibly the first application in the pyridine series, anddehydrogenation of the resulting 5 : 6 : 7 : 8-tetrahydro-l-rnethyl-$-carboline(XL) with palladised charcoal.98 Dehydrogenation of 2 : 3-cycloheptindoleto the benzaza-azulene (XLI) is conveniently effected with chl0ranil.9~The interconversions and rearrangements of sfiiro-oxindoles and -indoxylsJ.W. Hinman, E. L. Caron, and C. DeBoer, J . Amer. Chein. SOC., 1953, 75, 5864.E. H. Flynn, J. W. Hinman, E. L. Caron, and D. 0. Woolf, ibid., p. 5867.B1 C. Grundmann, H. Ulrich, and A. Kreutzberger, Chem. Ber., 1953, 86, 181.B2 A. Burger and E. D. Hornbaker, J . Amev. Chem. SOC., 1953, 75, 4579.B3 W. J. Close, ibid., p. 3617.O 5 E. Leete and L. Marion, Canad. J . Chem., 1953, 31, 775.O 6 Sir R. Robinson and J. E. Saxton, J., 1953, 2596.B7 C. F. Huebner, H. A. Troxell, and D. C. Schroeder, J . Amer. Chenz. SOC., 1953,94 Ann. Reports, 1952, 49, 206.75, 6887. g* G. R. Clemo and R. J. W. Holt, J . , 1953, 1313.W. Treibs, R. Steinert, and W. Kirchhof, Annalen, 1953, 581, 542 42 ORGANIC CHEMISTRY.have been reviewed, loo and alkylation of 3-formyl-1-methyloxindole has beenshown to give 3-alkoxymethylene derivatives and not 2-alkoxyindoles.lolOxindole and dibenzyl malonate gave the enol (XLII), yielding p-3-oxindolyl-propionic acid on catalytic reduction ; lo2 and analogously oxindole anddibenzyl oxalate gave the enol (XLIII), affording the long-sought 3-oxindolyl-acetic acid on reduction.lo3f)rrC(OH) CH,*CO,*CH,Ph f/),l=C(OH) *CO,*CH,Ph\/'#'?O (xLIII)(XLI I)\ / ' p OQuinoline. The Skraup synthesis has been reviewed.lo4 The so-called2 : 4-dihydroxyquinoline appears to exist as 4-hydroxy-2-quinolone in thesolid state and isomerises partly in solution to 2-hydroxy-4-quinolone butthere is no evidence for the lactim form; lo5 also the substance long thoughtto be 2 : 3-dihydroxy-4-quinolone is N : 4-dihydroxy-2-quinolone. lo6Benzoyl chloride reacts with quinaldine oxide to give 2-benzoyloxymet hyl-quinoline,1°7 and aqueous potassium dichromate converts tetrahydro-l-methylquinoline N-oxide into the lactam, 1 : 2 : 3 : 4-tetrahydro-2-oxoquin-oline.lO* Several examples of a novel ring contraction have been observed.Photodecomposition of quinoline-3 : 4-quinone-3-diazide (3-diazo-4-quin-olone) (XLIV), simply obtained from 3-amino-4-hydroxyquinoline, affordsindole-3-carboxylic acid ; in the pyridine series, however, the photodecom-position product (XLV) reacted with still unchanged material to give, afterspontaneous decarboxylation, (XLVI), but (XLV) could be obtained undersuitable conditions.10s Reaction of 3-aminolepidine with nitrous acid(XLIV) (XLV) (XLVI)(2 mols.) is reported to give 1 : 2 : 3 : 9-tetra-azaphenanthrene 3-0xide.l~~Further polycyclic bases have been isolated ll1 from coal-tar pitch : l-aza-pyrene,l12 4-aza-2 : 3-benzofluorene, quinindoline, and 13-azafluoranthene.isoQuinoZine. Considerable progress has been made in the synthesis ofreduced isoquinolines. Condensation of aldehydes with cyclohexenylethyl-amines gives decahydrohydroxy- or octahydro-isoquinolines directly,1l3 andN-methylmorphinan (XLVII; R = H) has been synthesised from isoquin-oline via l-benzyl-1 : 2-dihydro-5-hydroxy-2-methylisoquinoline,114 from100 B.Witkop and J. B. Patrick, J . Amer. Chem. SOC., 1953, 75, 2572.lo1 E. Wenkert, A.K. Bose, and T. L. Reid, ibid., p. 5514.loa P. L. Julian and H. C . Printy, ibid., p. 5301.lo3 P. L. Julian, H. C. Printy, R. Ketcham, and R. Doone, ibid., p. 8305.104 R. H. F. Manske and M. Kulka, Org. Reactions, 1953, 7 , 59.lo5 F. Arndt, L. Ergener, and 0. Kutlu, Chem. Ber., 1953, 86, 951.lo6 Idem, ibid., p. 957.l o 8 P. J . Scheuer, W. I. Kimoto, and K. Ohinata, ibid., p. 3029.log 0. Siis, M. Glos, K. Moller, and H.-D. Eberhardt, Annulen, 1953, 583, 150.110 D. W. Ockenden and K. Schofield, J., 1953, 1915.ll1 R. Oberkobusch, Chem. Ber., 1953, 86. 975.112 New synthesis : H. Medenwald, ibid., p. 287.113 R. Grewe, R. Hamann, G. Jacobsen, E. Nolte, and K. Riecke, Annulen, 1953, 581,114 C. F. Koelsch and N. F. Albertson, J . Amev. Chem. SOC., 1953, 75, 2095.lo7 I.J. Pachter, J . Amer. Chenz. SOC., 1953, 75, 3026.88WALKER : HETEROCYCLIC COMPOUNDS. 2432-phenyla~etyl-cyclohexanone,~~~ and from cyclohexenylacetonitrile via2-cyanomethyl-l-phenylacetylcyclohex-l-ene ; 115 the valuable drug 3-hydroxy-N-methyl-morphinan (XLVII ; R = OH) has been obtainedsimply from 9-meth-oxyphenylacetaldehyde and cy~lohexenylethylamine.~~~N-Methylmorphinan (XLVII; R = H) has been obtained from octa-hydrophenanthrene precursors by a method involving a fortuitous ring-X.Je*S-1 ' I R'CHO R' R'/\/\NR /\/'\NR /--\4,-\ / I 7 \ NHR - \-1 \-/(XLVI I) (A A H 2 'VIJ OH+ U J R CH,closure. 116 The parent ring-system of the erythrina alkaloids, erythrinane(XLIX), has been obtained by ring-closure of (XLVIII) with polyphos-phoric acid followed by reduction of the amide-carbonyl group with lithiumaluminium hydride.l17The von Pechmann reaction has beenreviewed.118 In a new synthesis, benzyl o-hydroxyphenyl ketones are con-densed with ethoxalyl chloride in pyridine to give Z-ethoxycarbonyliso-flavones, and thermal decarboxylation of the free acids gives the iso-flavones.ll9> lZo In the familiar synthesis using formic ester, methyl formateis reported to give 2-hydroxyisoflavanones while ethyl formate gives theisoflavone.lZ1 The isoflavones from the soya bean are possibly genistein anddaidzein.lz0, 122 In analogy with the flavones, examples of isomerisation of5 : 8-dihydroxyiso-flavones lZ3 and -flavonols lZ4 during demethylation ofmethyl ethers have been recorded, and vigorous demethylation of 2'-methoxy-flavones may cause rearrangement with interchange of the two benzenerings.lZ5 The occurrence of isomerisation is not readily predictable anddemethylation of 7-hydroxy-5 : 8 : 4'-trimethoxyflavylium chloride withhydriodic acid proceeds without isomerisation.126Oxygen-containing ring systems.115 H.Henecka, Annalen, 1953, 583, 110.116 D. Ginsburg and R. Pappo, J., 1953, 1624.117 B. Belleau, J. Amer. Chem. Soc., 1953, 75, 5765.118 S. Sethna and R. Phadke, Org. Reactions, 1953, 7, 1.119 W. Baker, J . Chadderton, J. B. Harborne, and W. D. Ollis, J., 1953, 1882.120 W. Baker, J . B. Harborne, and W. D. Ollis, ibid., p. 1860.121 X. Narasimhachari, D. Rajagopalan, and T. R. Seshadri, J .Sci. I n d . Aes., India,122 Cf. W. B. Whalley, J . Amer. Chem. Soc., 1953, 75, 1059.lZ3 \V. Baker, I. Dunstan, J. B. Harborne, W. D. Ollis, and R. Winter, Chenr. andInd., 1953, 277 ; W. B. Whalley, ibid. ; J., 1953, 3366.1 2 1 L. H. Briggs and R. H. Locker, J., 1949, 2157; D. M. Donnelly, E. M. Philbin,and T. S. Wheeler, Chenz. and Ind., 1953, 567.125 K. M. Gallagher, A. C. Hughes, M. O'Donnell, E. M. Philbin, and T. S. Wheeler,J., 1953, 3770.126 L. Ponniah and T. R. Seshadri, PYOC. Indian Acad. Sci., 1953, 38, A , 288.1953, 12, B, 287244 ORGANIC CHEMISTRY.Pachyrrhizon (L), isolated from " yam beans," provides a new variant ofthe rotenoid type with linear fusion of four rings instead of the usual linearfusion of rings B-C-D and opposed angular fusion of rings A and E.12'(R' = OH in tephrosin,otherwise H)IRotenone; R = H Elliptone; R = H Deguelin, tephrosin; R = HSumatrol; R = OH Malaccol; R = OH Toxicarol; R = OHPurine; Pteridine. Purine itself has been found in Nature for the firsttime in the form of its 9-p-D-ribofuranoside (nebularine) 129 in the mush-room Agaricm (CZitocybe) nebuZaris Batsch.; it is of biological interestbecause of its great toxicity to mice as compared with the parent unsubsti-tuted purine. Adenosine is involved in the biological transfer of methylgroups from methionine and the presence of adequate amounts of methioninein the media is necessary for microbiological accumulation of 5'-deoxy-5'-methylthioadenosine (" adenine thiomethyl pentoside ") ; 130 the " activeL+-l P YH* H-CH-€HCH,.S*CH,CH,*CH (NH,) *CO,- py\ +N ,/N\ INNOH"/\/ NH, (LI) N\/'X/ 1 11 ICH(OH)CH,-OHmethionine '' is formed from ATP and methionine 131 but contains nophosphate and is tentatively formulated as the thetin (LI).132Improved syntheses of pteroic and pteroylglutamic acid are reported inwhich an N-toluene-p-sulphonyl-p-amino-benzoate or -benzoylglutamate isallowed to react with a substituted propylene oxide (e.g.epichlorohydrin2 : 3-epoxypropaldehyde diethyl acetal) and the product is condensed with2 : 4 : 5-triamino-6-hydroxypyrimidine with subsequent removal of protect-ing groups.133 A belief that the lateral 3-carbon fragment of the pteridinepart of pteroic acid is of sugar origin is reinforced by the observation thatOH WI)127 H.Bickel and H. Schmid, Helv. Chirn. Acta, 1953, 36, 664.12* N. Lofgren and B. Liining, Acta Chew. Scand., 1953, 7, 225.lze G. B. Brown and V. S. Weliky, J . Biol. Chenz., 1953, 204, 1019.F. Weygand, R. Junk, and D. Leber, 2. physiol. Chem., 1952, 291, 191; R. L.Smith and F. Schlenk, Arch. Biochem. Biophys., 1952, 38, 167; F. Schlenk and R. L.Smith, J . Biol. Chem., 1953, 204, 27.152 J. Baddiley, G. L. Cantoni, and G. A. Jamieson, J . , 1953, 2662.133 D. 1. Weisblat, B. J. Magerlein, A. R. Hanze, D. R. Myers, and S. T. Rolfson,J . Amer. Chem. SOC., 1953, 75, 3625; D. I. Weisblat, B. J. Magerlein, D. R. Myers,A. R. Hanze, E. I. Fairburn, and S. T. Rolfson, ibid., p. 5893.131 G. L. Cantoni, ibid., p. 403BAILEY : ALKALOIDS.245fluorescyanin (ichthyopterin) 134 is 6-( 1 : 2-dihydroxyethy1)isoxanthopterin(LII) .135 Acetonyl, carboxyl, l-hydroxyethyl, and aminomethyl groupsare reductively removed from the 6-position of such substituted isoxantho-pterins by aluminium amalgam in alkaline media.13sNucleotides. Precise spectrophotometric studies have been carried outon cytidylic acids a and b,13’ which are respectively the 2’- and the 3’-phosphate,13* and there is general agreement that adenylic acids a and bare likewise the 2’- and the 3’-pho~phate.l~~-l~~ Thymidylic acid has beenidentified as thymidine 5’-ph0sphate.l~~ Methods for the synthesis ofunsymmetrical PP-diesters of pyrophosphoric acid have been discussedand their practical utility demonstrated by the syntheses of PP-diaden-osine 5‘-pyrophosphate and P1P2-diuridine-5’ pyrophosphate. 141 The struc-ture of coenzyme A la2 is now fairly certain and its chemistry and functionshave been reviewed.143J. W.Alkaloids.During the year under review volume 3 of Manske and Holmes’s “ TheAlkaloids ” has been published,l covering the cinchona, quinoline, quin-azoline, lupin, glyoxaline, solanum, veratrum, and ipecacuanha alkaloids,%phenylethylamines, and the ephedra bases up to 1952. The biogenesis ofthe pyrrocoline alkaloids has been discussed.2 Sprouting barley has beenfound to transform ( &)-[2-14C]tyrosine into radioactive N-methyltyramineand hordenine ; the methylenedioxy- and N-methyl groups of protopine areformed from the methyl group of [14C]methylmethionine.4 Neither nicotinicacid nor its ethyl ester is utilised in the biosynthesis of ni~otine.~More details of the work on the stereochemistry of thesealkaloids have appeared.6-Hydroxytropinone has been resolved andthen reduced, giving a 3 : 6-dihydroxytropane (I) identical with the productobtained by hydrolysis of valeroidine.’Lupinus sericeus Pursh. contains at least five alkaloids,8Tropane group.Lupinane group.134 M. Polonovski, R. G. Busnel, and M. Pesson, Compt. vend., 1943, 217, 163.135 R. Tschesche and F. Korte, Angew. Chem., 1953, 65, 600.136 S. Nawa, S. Matsuura, and Y . Hirata, J . Amer. Chem. SOC., 1953, 75, 4450.137 R. J. C. Harris, S. F. D. Orr, E. M. F. Roe, and J. F. Thomas, J., 1953, 489;J. J. Fox, L.F. Cavalieri, and N. Chang, J . Amer. Chem. Soc., 1953, 75, 4315.138 L. F. Cavalieri, ibid., p. 5268.139 D. M. Brown, G. D. Fasman, D. I. Magrath, A. R. Todd, W. Cochran, and M. M.Woolfson, Nature, 1953, 172, 1184; J. X. Khym, D. G. Doherty, E. Volkin, and W. E.Cohn, J . Amer. Chem. Soc., 1963, 75, 1262.l40 A. M. Michelson and A. R. Todd, J., 1953, 961.1 4 1 S. M. H. Christie, D. T. Elmore, G. W. Kenner, A. R. Todd, and F. J. Weymouth,142 Cf, Ann. Reports, 1952, 49, 280; J. Baddiley, E. M. Thain, G. D. Novelli, and143 G. D. Novelli, Fed. Proc., 1953, 12, 675; F. Lynen, ibid., p. 683.1 Ed. R. H. F. Manske and H. L. Holmes, Academic Press, New York, 1953.2 E. Wenkert, Chem. and Ind., 1953, 1088; Sir R. Robinson, ibid., p. 1317.3 E. Leete and L.Marion, Canad. J. Chem., 1953, 31, 126.4 M. Sribney and S. Kirkwood, Nature, 1953, 171, 931.ti R. F. Dawson, D. R. Christman, and R. C. Anderson, J . Amer. Chew Soc., 1953,7 A. Stoll, A. Lindenmann, and E. Jucker, Helv. Ckiw. Acta, 1953, 36, 1506.8 L. 3 5 a r . i ~ N. J. Leonard, and B. P. Moore, Canad. J. Chem., 1953, 31, 181.J., 1953, 2947.F . Lipmann, Nature, 1953, 171, 76.75, 5114. 6 Ann. Reports, 1952, 49, 219; cf. this ~ l . , p. 164246 ORGANIC CHEMISTRY.one of which, lupanoline Cl,H,,02N2 (11), appears to be new. It is a mono-acid base containing a hydroxyl and an amide group; the hydroxyl groupwas readily lost and could not be acylated. Lithium aluminium hydridereduction of the alkaloid gave an oily base C15H2,N2, different from sparteine(111) and from a-isosparteine (I11 ; but with both C(,,-H and C(,,,-H cis to the7-9 bridge), and was apparently the hitherto unknown p-isosparteine (IV ;Y = H2).This supposition was confirmed when dehydrogenation followedby hydrogenation gave sparteine (111). Ferricyanide oxidation of p-iso-sparteine (IV; Y = H,) gave (IV; Y = 0) identical with the substanceobtained from lupanoline by dehydration followed by catalytic hydrogen-a t i ~ n . ~(111) (IV)Structure (V) previously suggested for carpaine hasbeen disproved by the isolation of myristic acid from a two-stage Hofmanndegradation. Dehydrogenation yielded deoxycarpyrinic acid (VI) and2 mols. of hydrogen; permanganate oxidation of (VI) gave pyridine-2 : 6-dicarboxylic acid.lo Dehydrogenation of ethyl carpamate resulted in theloss of 3 mols. of hydrogen and the formation of a substance having theproperties of a 3-hydroxypyridine, indicating the presence in the alkaloidof a 3- or 5-hydroxypiperidine ring. l1 Finally, methyl N-methylcarpamatemethiodide (VII) was subjected to exhaustive methylation with hydrogen-ation at each stage, and the nitrogen-free product was oxidised to 12-oxo-tetradecanoic acid (VIII), showing that carpaine had structure (IX).127 CMefCH,] , 0 Me!&-[CHJ ,*C02H !:(J-[CHJ ,*C02MePyridine group./\Me, I- I,r, "i H(V) (VI) (VII)Yo 0MeCH,*CO.[CH,],,CO,H Me lh \N/-[CH21 7-(VIII) H (1x1isoQuinoZine group. A new alkaloid, thalictricavine, C2,H2,0,N (X),has been isolated from CorydaZis tuberosa DC.; demethylenation followedby methylation converted it into corydaline, and hydrastic acid was obtained10 H. Rapoport and H. D. Baldridge, J . Amer. Chem. Soc., 1951, 73, 343; 1952, 74,12 H. Rapoport, H. D. Baldridge, and E. J. Volcheck, J . A m y , Ckem. Soc., 1953, 75,9 B. P. Moore and L. Marion, Canad. J . Chem, 1953, 31, 187.5365.5290.11 T. R. Govindachari and N. S. Narasimhan, J., 1953. 2635BAILEY ALKALOIDS. 24ion permanganate oxidation. l3lodal and 6 : 7-methylenedioxyphthalide by the Hope-Robinson method.14Corlumine (XI) has been synthesised fromI I (XI (XI) O-CH,Emetine.15 The synthesis of emetine (XIII) has been described inThey were cyclised andR CH,-H C0,Et CH,-C;/< 'LO,Et 'CH,-CH C0,Et(i) NCCH,*CO,Et(ii) EtIdetail.16 Two isomers of (XII) were obtained.Et0,C /y!3 EtO,\ CH4 Eta *CO,Et E t C H c\ CN 'CNMe0OMeMeO'oc(i) POCl,; - (ii) H,-Pt Et.H NCH,*CH,(XW c\/ (XIII) CH,reduced to (XIII); one of the isomers obtained (racemic?) did not depressthe m. p. of natural emetine. (&)-Rubremetiniurn bromide has been syn-(i) H,-Pd; (ii) P,O,; (iiij Dil. H,SO,, -CO, i13 R. H. F. Manske, J . Amer. Chem. SOC., 1953, 75, 4928.14 W. M. Whaley and M. Meadow, J.. 1953, 1067. l5 Ann. Reports, 1952, 49, 220.1 4 R. P. Evstigneeva, R. S. Livshits, M. S. Bainova, L. I. Zakharkin, and N. A.Preobrazhenskii, Zhuv. Obshchey Khim., 1952, 22, 1467; Chem. Abs., 1953, 47, 5949248 ORGANIC CHEMISTRY.thesised 17 from the oxoquinolizine (XIV) by condensation with a-cyano-N-(2-3’ : 4‘-dimethoxyphenylethy1)acetamide to give (XV) which was thenconverted into (XVI) which is structurally identical with O-methylpsycho-trine; this was then oxidised to rubremetinium bromide (XVII).Tietz andMcEwen l8 repeated the experiments of Openshaw et aZ.15 on the reduction ofthe rubremetinium cation to compounds of structure (XVIII) and found anuptake of four hydrogen atoms instead of the two required by (XVII).These results have been explained in terms of structure (XIX) for therubremetinium cation, its optical activity being due to non-planaritybecause of crowding around the positions marked with an asterisk.(XVIII) (XIX) +Indole. Details of the infra-red spectra of alstonine l9 and its derivativeshave been published.2o Corynantheine (XX) and dihydrocorynantheine(XXI) may be separated by using Craig’s counter-current extraction method.21Corynantheidine has been shown 22 to be a stereoisomer of dihydrocoryn-antheine (XXI) and not of corynantheine (XX) since it contains a C-methylgroup and no XH,; it was dehydrogenated to alstyrine (XXII) and hydro-lysis afforded an amorphous aldehyde, Wolff-Kishner reduction of whichE t Et(XXIV)gave corynantheidane (XXIII).The stereochemistry of the yohimbine-type alkaloids has been studied by application of the methods of conform-1 7 A. R. Battersby, H. T. Openshaw, and H. C . s. Wood, J.. 1953, 2463.18 R. F. Tietz and W. E. McEwen, J . Amev. Chem. SOC., 1953, 75, 4945.10 Ann. Repovts, 1952, 49, 223. 2o F. E.Bader, Helv. Chem. Acta, 1953, 36, 215.21 R. Goutarel, M. M. Janot, R. Mirza, and V. Prelog, ibid., p. 337.22 M. M. Janot, R. Goutarel, and J. Chabasse-Massonneau, Bull. Soc. chim., 1953, 1033BAILEY : ALKALOIDS. 249ational analysis.23 Ozonolysis of yohimbine alkaloids leads to 9-memberedlactams which then form linear pyrroloquinolones (XXIV) .24The alkaloid reserpine has been isolated from RauwoZJia serpentinaBenth.25, 269 27 and from Rauwolfia heterophylla Roem. and Schult.28 An-alysis indicates a formula C3,H,oOgN,,25~ 27, 28 but C3,H,0,,N, has also beensuggested.26 The alkaloid contains six methoxyl groups and is hydrolysedto reserpic acid, 3 : 4 : 5-trimethoxybenzoic acid, and methanol; the alkaloidis re-formed by reaction of methyl reserpate with 3 : 4 : 5-trimethoxybenzoylchloride.25 Permanganate oxidation of reserpic acid afforded the acid (XXV),potash fusion yielded 5-hydroxyisophthalic acid (XXVI), and seleniumdehydrogenation gave yobyrine.From these observations structure(XXVII) has been suggested for reserpic acid.25C02HM e o / f \ l d ' l/\\/ HO,d llOH \ P I g y N )H\CO,HMeOl IJNHCO*C02H \/ mHO,C (,) OH(XXVI) (XXVII) OMeThe structure of the third alkaloid from Pentaceras australis Hook hasbeen shown to be 4-methylthio-6-oxocanthine (XXVIII ; R = SMe).29Mild alkaline hydrolysis gave the corresponding acid which readily re-cyclised to form the alkaloid ; prolonged hydrolysis yielded methanethiol and(XXVIII; R = OH) which did not react with o-phenylenediamine and wasoxidised t o p-carboline-l-carboxylic acid (XXIX).This was convertedinto (XXVIII; K = OH) by reaction of its acid chloride with diethylethoxymagnesiomalonate followed by hydrolysis of the resulting ester.Treatment of (XXVIII; R = OH) with phosphorus oxychloride gave(XXVIII; R = Cl), and heating the chloro-compound with potassiummethyl sulphide yielded the alkaloid (XXVIII ; R = SMe).Lysergic acid (XXX; R = C0,H) and its derivatives are readily isomer-ised by mineral acids to compounds containing a true naphthalene system(XXXI), the products being isolated as their acetyl derivatives. Structure(XXXI) has been proved by synthesis from 4-methoxynaphthostyril(XXXII). Reduction of (XXXIV) gave dihydronorlysergic acid (XXXV) ; 3023 R.C. Cookson, Chem. and Ind., 1953, 337 ; A. Le Hir and R. Goutarel, Bull. SOC.24 €3. Witkop and S. Goodwin, J . Amer. Chem. SOC., 1953, 75, 3371.25 L. Dorfman, C. F. Huebner, H. B. MacPhillamy, E. Schlittler, and A. F. St. And+,2 6 M. W. Klohs, M. D. Draper, F. Keller, F. J. Petracek, J . Amer. Chem. SOC., 1953,28 C. Djerassi, M. Gorman, A. L. Nussbaum, and J. Reynoso, ibid., p. 5446.29 E. R. Nelson and J. R. Price, Austral. J . Sci. Res., 1952, 5, A , 768; cf. Ann.30 A. Stoll and Th. Petrzilka, Helv. Chim. Ac~u, 1953, 36, 1125, 1137.chim., 1953, 1023, 1027; W. Klyne, Chem. and Ind., 1953, 1032.Experientia, 1953, 9, 368; cf. Helv. Chim. Acta, 1954, 3'9, 59.75, 4867. 2 7 N. Neuss, H. E. Boaz, and J. W. Forbes, ibid., p. 4870.Reports, 1952, 49, 224250 ORGANIC CHEMISTRY.the base (XXXIII; R = Me) has been converted into (XXXI) by reactionwith ethyl bischloromethylmalonate followed by hydrolysis and decarboxyl-at ion .31WH R/=\fLf\/ ‘2;(XXXIII)(i) NCCH(CHO),(ii) ZnCI, - (iii) EtOH-H,SO,(iv) Ac,O(i) LiAIH,;(ii) HBr, then Ac,O(iii) (NH,),SO, tC02EtAc(XXXIV)(i) Me1(ii) H,-PtNa- - BuOH(XXXV)OMe R(i) HCIf---(ii) Ac,OPyrrolizidine grozcfi.The structure (XXXVI) 32 previously accepted formonocrotaline is incorrect .33 The infra-red spectrum of the alkaloid showsonly a single ester-carbonyl band, and has no carbonyl band correspondingto a five-membered lactone ring ; hence structure (XXXVII) is preferred.Monocrotaline reacts with thionyl chloride, forming a cyclic sulphite ester(XXXVIII), indicating the presence of an a-glycol grouping; the alkaloid isMe qle Me YH TH HO ~ C H 2 * C O o 7 C - T - O H oc-y-y--$? co 1 H Me Me\CO-CHMe / ( O A r , w c (XXXVI I)’!(XXXVI)(XXXVIII) (XXXIX)rapidly oxidised by lead tetra-acetate ; addition of o-phenylenediamine tothe oxidation mixture gave 2-hydroxy-3-methylquinoxaline (XXXIX) .Similarly, structure (XL) has been suggested for di~rotaline,~~ and (XLI)31 F.R . Atherton, F. Bergel, A. Cohen, B. Heath-Brown, and A. H. Rees, Chem.32 R. Adams and F. B. Hauserman, J . Amer. Chem. SOC., 1952, 74, 694.33 R. Adams, P. R. Shafer, and B. H. Braun, ibid., p. 5612.34 R. Adams and B. L. VanDuuren, ibid.. 1953, 75, 2377.and I n d . , 1953, 1151BAILEY : ALKALOIDS.25 1for riddelline.35usaramoensine C, ,H,,O,N.sinecic acid, isomeric with integerrinecic acid.36Crotalaria zcsaramoensis E. G. Baker contains a new alkaloid,Hydrolysis gave retronecine and usaramoen-SHMe ?H,.OHO:C-C<H=CM~-C :O Ye O:C--CH,~-CH2-C:0 I OH I~ I0 I C H Z - O\N\/(XL) (XLI)Dihydrolycorineanhydrornethine (XLII) has been synthesised, andstructure (XLIII) suggested for l y ~ o r i n e . ~ ~ Another group of workersHOA HO/) HO-/O\/\/\/ I llEt /o\AA,\\O/\/\/NMe \o/\/\NHZC I II I HZC 1 II 11 HZC(XLI I) (XLIII) (XLIV)prefers (XLIV) and it is thought that the phenanthridine skeleton is formedby re-arrangement during the Hofmann degradation.38Quinazolone group. The optically active form of febrifugine (XLVI)has been synthesised from (-)-p-benzamido-p-tetrahydrofurfurylpropionicCH2H,C’ ‘CI3-q ( i ) NEt,;~ F H C H , - C O , H BrH,C YH-CH, ( i i ) BzC1__)I I I A 0 - NHBz NH2(XLV(XLVII)(i) Quinazol-4-one;(ii) HBr 1H(XLVI)acid (XLV).a9 The infra-red spectrum of febrifugine is in agreement withstructure (XLVI) ; the infra-red spectrum of isofebrifugine shows that it isthe cyclic ket a1 (XLVI I).35 R.Adams and B. L. VanDuuren, J . Amer. Chem. Soc., 1953, 75, 4638.36 Idem, ibid., p. 4631; cf. this vol., p. 187.37 R. B. Kelly, W. I. Taylor, and K. Wiesner, J . , 1953, 2094; I<. Wiesner, W. I.Taylor, and S. Uyeo, Chem. and I n d . , 1954, 46.38 E. J. Forbes, J. Harley-Mason, and Sir R. Robinson, Chem. and I n d . , 1963,946,1317.39 B.R. Baker, F. J. McEvoy, R. E. Schaub, J. P. Joseph, and J. H. Williams, J .Ovg. Chem., 1953, 18, 178; cf. Ann. Reports, 1952, 49, 226252 ORGANIC CHEMISTRY.A new alkaloid, arborine C1,HI4ON,, has been obtained from the leavesof Glycosmis arborea Correa. Alkaline hydrolysis yielded N-methyl-anthranilic acid, phenylacetic acid, and ammonia ; reduction of the alkaloidafforded a dihydro-derivative which gave phenylacet aldehyde on hydrolysis.Structure (XLVIII), thus indicated, was confirmed by synthesis from phenyl-R RA / \ N //\/\NH I II 1- A CO~NH,1, \/ IINMe.CO.CH,Ph - I \/\a; 11 lkH2Ph \/\E;-CHP1l(XLVI 11) (XLIX)acetyl chloride and N-methylanthranilamide.40 The same substance hasalso been isolated by Chatterjee and M a j ~ r n d a r , ~ ~ who found that ozonolysisor periodic acid oxidation of the alkaloid gave benzaldehyde and prefer thealternative formula (XLIX). The infra-red spectrum of the alkaloid shouldprovide a decision.Steroid alkaloids.A review of this group has recently appeared.42Kryptogenin (L; R = OH) has been converted into the iodide (L; R = I)via the monotoluene-p-sulphonate ; the iodide was then transformed intothe phthalimido-derivative (LI) and thence into solasodine (LII).43 A newMe , , C H , y a Me , /CHZ*cy,/"\PHMe CH-COYHz07L.- yoMe I /y/\:o/CHMeH-COp?):o ' RCH,ppY-' (LI) / / \ \-/AM7\/ -HO/\/\(L)HO/')\)\)glucosidic alkaloid, isorubijervosine, has been isolated from Veratrumeschscholtzii Gray and shown to be 3~-(D-g~ucosy~)solanid-5-en-lS-ol (LIII) .44Details of the degradation of jervine to a nitrogen-free pr0duct,4~ and ofthe acetolysis of dia~etyljervine,~~ have now been published.42The suggestion 47 that cevagenine is the true alkamine of cevidine andveratridine has been disproved by hydrolysis of the alkaloids at O", to a newalkamine, veracevine.This substance shows no carbonyl absorption in40 D. Chakravarti, R. N. Chakravarti, and S. C. Chakravarti, J., 1953, 3337; Ex-4 1 A. Chatterjee and S. G. Majumdar, J . Amer. Chem. SOC., 1953, 76, 4365.42 J . McKenna, Quart. Reviews, 1953, 7, 231.43 F. C . Uhle, J . Amer. Chem. SOC., 1953, '75, 2280.44 M. W. Klohs, M. D. Draper, F. Keller, W. Malesh, and F. J. Petracek, ibid., p.4 6 0. Wintersteiner and M. Moore, ibid., p.4938.4 7 Ann. Reports, 1952, 49, 228.perientia, 1953, 9, 333.2133. 4 6 J. Fried and A. Klingsberg, ibid., p. 4929OVEREND : CARBOHYDRATES. 253its ultra-violet or its infra-red spectrum ; further action of alkali convertsveracevine into cevagenine (which contains a carbonyl group) .48 Cevageninehas been shown to contain an a-ketol grouping, and a further isomer ofcevagenine, y-cevine, has been isolated.49 The physical properties of vera-cevine and y-cevine and their derivatives suggest that the two compoundsHO*YH,(LWare identical. y-Cevine has also been isolated from commercial veratrine,after removal of cevidine and veratridine, along with a new alkaloid cevacineC,,H4,09N, which is a monoacetate ester of y - ~ e v i n e . ~ ~ Jacobs and Pelle-tier 51 consider that a structure of type (LIV) for veracevine gives a betterexplanation of the type of hydrocarbon obtained by selenium dehydrogen-ation than does a conventional steroid-type formula.A.S. B.8. CARBOHYDRATES.Last year there was a comprehensive Report on polysaccharides, sothis Section will be restricted mainly to a consideration of the simpler sugarsand their derivatives, and then only to those topics which have attractedmost attention. Since the last account of monosaccharides, " Rules ofCarbohydrate Nomenclature " have been agreed by the Publication Com-mittee of the Chemical Society, and by the American Chemical Society.Detection, Estimation, and Separation.-To fill the need for methods toindicate the positions of sugars on chromatograms, several new colourreagents have been developed and known reagents have been made morespecific.A quantitative technique using benzidine in acetic acid is satis-factory for most common sugars and their methylated derivatives, exceptketoses. A slightly alkaline methanolic solution of sodium borate andphenol-red gives good definition with dihydroxyacetone, various pentoses,hexoses, and disaccharides, and a number of p01yols.~ Resorcinol-4 : 6-di-sulphonic acid and 9-anisidine phosphate in ethanol have been used for48 S. W. Pelletier and W. A. Jacobs, J . Amer. Chem. SOC., 1953, 75, 3248.40 A. Stoll and E. Seebeck, Nelv. Chim. A d a , 1953,36,189 ; A. Stoll, D. Stauffacher, andE. Seebeck, ibid., p. 2027 ; cf.N. Elming, C . Vogel, 0. Jeger, and V. Prelog, ibid., p. 2022.5O S. M. Kupchan, D. Lavie, C. 'CV. Deliwala, and R. Y . A. Andoh, J . Amer. Chew.SOC., 1953, 75, 5519; S. M. Kupchan and D. Lavie, ibid., 1954, 76, 314.51 W. A. Jacobs and S. W. Pelletier, .J. Org. Chem., 1953, 18, 765.1 E. J. Bourne, Ann. Reports, 1952, 49, 235.3 Editorial Report on Nomenclature, J . , 1952, 5108. * J. K. N. Jones and J. B. Pridham, Nature, 1953, 172, 161.D. J. D. Hockenhull, ibid., 1953, 171, 982.8 E. Lunt and D. Sutcliffe, Biochem. J., 1953, 55, 122.7 S. Mukherjee and H. C. Scrivastava, Nature, 1953, 169, 330.L. N. Owen, ibid., 1951, 48, 168254 ORGANIC CHEMISTRY.detection. Methods are now available for distinguishing deoxy-sugars,glycals, and methylpentoses from other sugars on paper chromatogramsand for estimating 2-deoxy-~-glucose colorimetrically.s Diethyl 9-phenylene-diamine sulphite, used in conjunction with hydrolysis on paper by in-vertase,1° can be employed for the identification of raffinose in the presenceof fructosylsucrose (kestose) .ll Pentoses may interfere appreciably withthe determination of hexoses by the anthrone reagent.l2 An improvedanthrone reagent has been described l3 and a procedure using a modifiedreagent has been developed as a specific test for ket0-s~gars.l~ A modifiedorcinol test can now be used to differentiate between ketoses and othersugars including keto-aldonic acids.l5 It is reported that the Elson-Morgantest, originally considered characteristic for hexosamines, is given by apentosamine.16 3 : 4-Dinitrobenzoic acid has been used for the quantitativecolorimetric estimation of sugars l7 and two improved copper reagents-onefor use in the colorimetric, the other for the iodometric technique-forquantitative work, have been described.l 8The use of ultra-violet and infra-red absorption spectra in structuraldetection of sugars is reported.lg3 2o Anomeric forms can be differentiatedsince measurements over the range 730-960 cm.-l enable derivatives ofD-glucopyranose to be assigned to either the CL- or @-series, no matter whetherthey are reducing sugars, methylglucosides, or polysaccharides : the a-anomers absorb at 844 -J-- 8 cm.-l and the @-anomers a t 891 & 7 crn.-l.Furthermore an indication may be obtained of the positions of the glycosidiclinkages in a polyglucose.21A neat procedure for correlating the structure of glycosides consists inthe reduction, either catalytically or with sodium borohydride, of thedialdehyde formed by periodate oxidation of the sugar glycoside, and anexamination of the resulting alcoho1.22 The dialdehydes (I) from the pento-furanosides and hexopyranosides give the alcohol (11). Pentopyranosidesyield the dialdehydes (111) and then the alcohol (IV).As there is only onecentre of asymmetry (*) in (11) or (IV) all the methyl C+D- and p-L-hexo-pyranosides should give the same optically active alcohol ( A ) . Similarly,all the methyl P-D- and a-L-hexopyranosides should furnish the enantio-morph of ( A ) . The relation will hold for the pentofuranosides, and similarlyit should exist among the alcohols (IV) produced from methyl a- and p-D-and -L-pentopyranosides.Experiments with the glycosides of D-glucose,D-mannose, D-galactose, D-XylOSe, and L-arabinose have confirmed theserelations and shown that glycosidic configurations can be correlated. The8 J. T. Edward and Deirdre M. Waldron, J., 1952, 3631.9 F. B. Cramer and G. A. Neville, J. Franklin Inst., 1953, 256, 379.10 I<. T. Williams and A. Bevanue, Science, 1951, 113, 582.11 H. C. S. De Whalley, Intern. Sugar J., 1952, 54, 158.12 R. Johanson, Nature, 1953, 171, 176.13 N. J. Fairbairn, Chern. and Iqzd., 1953, 86.14 R. Johanson, Nature, 1953, 172, 956.16 M. L. Wolfrom and K. Anno, J . Amer. Chern.SOL., 1953, 75, 1038.1 7 E. Bore1 and H. Deuel, Helv. Chim. Acta, 1953, 36, 801.la M. Somogyi, J. Biol. Chem., 1952, 195, 19.19 H. Bredereck, G. Hoschele, and W. Huber, Chem. Ber., 1953, 86, 1271.20 S. A. Barker, E. J. Bourne, M. Stacey, and D. H. Whiffen, J., 1954, 171;2 1 S. A. Barker, E. J. Bourne, M. Stacey, and D. H. Whiffen, Chem. and Ind., 1953,196.22 M. Abdel-Akher, J. E. Cadotte, R. Montgomery, F. Smith, J. W. Van Cleve, andl5 J. H. Williams, zbid., 1952, 170, 894.R. L. Whistler and L. R. House, Analyt. Chem., 1953, 25, 1463.B. A. Lewis, Nature, 1953, 171, 474OVEREND CARBOHYDRATES. 255method is also applicable to the glycosides of 6-deoxyhexopyranosides andoligosaccharides.Hexop yranosides, 10,- iFi ZH, *is] pentofuranosides 1 - - H,*OH7H.O H*OCH2*OH H2*OH(1) (11)To determine the rotation of an unknown a-glycoside it is usual to applyHudson's isorotation rules, by appropriate combination of the rotation ofthe p-anomer with the rotations of a related anomeric pair of glycosides.Ithas been suggested-and evidence provided 23 supports the idea-that, inthe related anomeric pair employed, the aglycone should bear the greatestpossible structural similarity to the aglycone of the unknown or-glycoside.Ring paper-chromatography for the separation of sugars has beendiscussed.24 I t is claimed 25 that limited use can be made of cellulose sheets(approx. Q in. thick) as chromatographic supports for separating a relativelylarge amount of a sugar mixture. Paper-chromatography and detection 26of phosphate esters 27 including phosphorylated hexose esters 28 have beendescribed.In a new method for oligosaccharides, the sugar is converted onthe chromatogram into the corresponding N-benzylglycosylamine,29 con-siderable increases in RF values of oligosaccharides being reported.Chromatography of un-neutralised polysaccharide hydrolysates is feasibleif aniline phosphate or phthalate spray is used for detection of the sugar.soMobility on the paper has been correlated with carbohydrate structure : 31regularities for homologous oligosaccharide series lead to a straight linecharacteristic of each series, when the logarithm of a partition function(obtained from single- or multiple-ascent experiments) is plotted againstmolecular size; the generalisation is proposed that increasing the size of asaccharide by one hexose unit will decrease the mobility by an amountwhich depends on the type of hexose unit being added and on its mode ofattachment. Examples included oligosaccharides of the starch, dextran,levan, inulin, and galactan types.Several workers have stressed that caremust be exercised in interpreting chromatograms. Apparently on unwashed23 W. A. Bonner, M. J. Kubitshek, and R. W. Drisko, J. Ames.. Chem. SOC., 1962, 74,25 L. S. Cuendet, R. Montgomery, and F. Smith, J . Attzer. Chem. SOC., 1963, 75, 2764.28 H. E. Wade and D. M. Morgan, Nature, 1953, 171, 529.2 7 E. Fletcher and F. H. Malpress, ibid., p. 838; S. Burrows, F. S. M. Grylls, and28 J. Dulberg, W. G.Roessler, T. H. Sanders, and C. R. Brewer, J . Biol. Cheln.,3O B. D. E. Gaillard, ibid., p. 1160.31 D. French and G. M. Wild, J . Awzer. Chent. SOC., 1953, 75, 2612.5082. 24 T. Bersin and A. Miiller, Helv. Chinz. A d a , 1952, 35, 475.J. S. Harrison, ibid., 1952, 170, 800.1962, 194, 199. 2B R. J. Bayly and E. J. Bourne, Nature, 1953, 171, 386256 ORGANIC CHEMISTRY.paper, heating to develop the spots results in interconversion of aldose andketose sugars 32 by alkaline impurities. When diabetic urines or glucosewas chromatographed with a butanol-ammonia system, two extra spotswere observed 33 and later identified 34 as glucosylamine and diglucosylamine.For methyl glycosides of fructose and galactose it was possible to separatein a single operation on a column of powdered cellulose not only ring-isomericglycosides, but also anomeric glyco~ides,~~ the eluting solvent being theupper phase of a mixture of ethyl acetate, technical pyridine, water, andbenzene (5 : 3 : 3 : 1). Many applications of the Whistler-Durso technique 36for sugar separations continue to appear.A gradient elution analysisprocedure, suitable for the separation of oligosaccharides has been de-scribedJ37 employing a continuously increasing concentration of ethanolin water. Methylpentoses, pentoses, and aldohexoses are separable on astarch column with butanol-propanol-water (4 : 1 : l).38 Favourable con-ditions have been determined for the selective separation on alumina of thetwo constituents of starches from maize, tapioca, and potatoes.39Ionophoretic separation of sugars, as their borate complexes, has beenin~estigated.~~ The value of the original method has been extended byimprovements in the apparatus, enabling potential gradients of 40-60vlcm. to be applied safely for 1-3 hours.41 Evidence has been adduced42suggesting that aldehyde-forms of sugar derivatives interact with borate ions,and hence migrate on ionophoresis.The method has been used43 forseparation of 2 : 3-, 2 : 4-, and 3 : 4-di-O-methylrhamnopyranose which aredifficult to resolve completely in other ways.The capacity of many sugars to form borate complexes also facilitatestheir separation by ion-exchange resins. The sugars are adsorbed on borate-treated strong base anion-exchange resin and eluted with boric-boratebuffers.44 Disaccharides are readily separated from monosaccharides, andcomponents of hexose and pentose mixtures are easily resolved as are hexose-pentose mixtures.The method is suitable for preparative purposes.45 Com-bination of the borate complex adsorption technique with elution by buffersprogressively adjusted for pH and ionic character is useful for separation ofthe commonly encountered monophosphorylated sugars.4G Although it hasbeen suggested 47 that columns of " Amberlite IRA 400 (OH-) " might beused for the separation of reducing and non-reducing carbohydrates, certainreducing sugars, and more particularly glucose and fructose, are degradedto organic acids by this resin.48 Furthermore some conversion of D-glucose32 R.B. Duff, Ckem. and Ind., 1953, 895.33 R. J. Ba.yly, E. J. Bourne, and M. Stacey, Nature, 1951, 168, 510.34 Idem, zbzd., 1952, 169, 876.3 5 J. A. Augestad, E. Berner, and E. Weigner, Chem. and Ind., 1953, 376.36 R. L. Whistler and D. F. Durso, J . Anzer. Chem. Soc., 1950, 72, 677.3 7 R. S. Alm, A d a Chem. Scand., 1952, 6, 1186. 38 S. Gardell, ibid., 1953, 7, 201.3O E. H. Fischer and W. Settele, Helv. Chim. Acta, 1953, 36, 811.40 R. Consden and W. M. Stanier, Nature, 1952, 169, 783 ; L. Jaenicke, Xaturwiss.,4 1 D. Gross, Nature, 1953, 172, 908.42 A. B. Foster, J., 1953, 982.44 J. X. Khym and L. P. Zill, J . Anzer. Chem. SOC., 1952, 74, 2090.45 L. P. Zill, J. X. Khym, and G. M. Cheniae, ibid., 1953, '45, 1339.4 6 J. X. Khym and \V.E. Cohn, ibid., p. 1153.4 7 S. Roseman, R. H. Abeles, and A. Dorfman, Arch. Biochem., 1952, 36, 232.4 8 J . D. Phillips and A. Pollard, Nature, 1953, 171, 41; L. I. Woolf, ibid., p. 841.1952, 39, 86; A. B. Foster and hl. Stacey, J . Appl. Chem., 1963, 3, 19.43 Idem, Chem. and Ind., 1952, 828OVEREND : CARBOHYDRATES. 257into D-fructose was observed49 on passage through a strongly basic anion-exchange resin [" IRA 400 (OH-) "]. Much lactic acid was produced whensolutions of glucose, sucrose, and fructose were passed through columns ofDowex 2 resin and eluted with dilute hydrochloric acid.50Anhydro-compounds.-Cleavage of epoxide rings in anhydro-sugars con-tinues to attract interest. The action of phenols on some ethylene oxidederivatives has been in~estigated.~~ In the examples studied (1 : 2-5 : 6-diepoxyhexane, 1 : 2-5 : 6-dianhydro-3 : 4-O-isopropylidenemannitol, and5 : 6-anhydro-1 : 3-2 : 4-di-O-ethylidene-~-sorbitol), rupture of the anhydro-ring(s) occurred and the aryl substituent entered the molecule at the primaryhydroxyl group.Further examples of the action of acidic reagents onethylene oxide anhydro-sugars have been reported. The chief product fromthe reaction of methyl 2 : 3-anhydro-4 : 6-O-benzylidene-a-~-mannoside (V)with hydrochloric acid is methyl 3-chloro-3-deoxy-a-~-altroside.~~ Treat-ment of methyl 3 : 4-anhydro-6-O-trityl- a-D-galactoside with the same acidaffords as expected methyl 3-chloro-3-deoxy-oc-~-guloside and methyl4-chloro-4-deoxy-a-~-glucoside.~~ The reaction of the 2-O-acetate of thelatter anhydride with hydrogen chloride in acetone has been re-investigated 54and the presence of both gulose and galactose derivatives in the product hasbeen confirmed.53 It is suggested that the galactose derivative is formed asillustrated. This reaction merits further investigation since it might providea route to cis-glycols from epoxides.+CMe, CMe,/ \ + H +Ho*(fMea CleavageMe,C-OH-+ H d ' O + yay + T><O$/ a t a \+ I/ q).pH HH H H H H 1-AThe view expressed in the Report for 1951 concerning the action ofGrignard reagents on sugar epoxides is supported by the finding that methyl2 : 3-anhydro-4 : 6-O-benzylidene-a-~-alloside is converted by phenyl-magnesium bromide into methyl 4 : 6-0-benzylidene-2-bromo-2-deoxy-a-~-altroside.Likewise, with ethylmagnesium bromide or iodide it furnishesthe 2-bromo- or 2-iodo-altroside derivative : no glucose isomer is obtained.55However, the overall picture is confused since, when the anhydro-allosidereacted with methylzinc iodide the product was methyl 4 : 6-O-benzylidene-3-deoxy-3-iodo-a-~-glucoside. 55 The action of diethylmagnesium on (V)under a variety of conditions has been in~estigated.~~ In ether the soleproduct is methyl 4 : 6-O-benzylidene-3-deoxy-3-C-ethyl-a-~-altro~ide (V1)-a novel branched-chain sugar. The reaction is not straightforward and intoluene leads to a complex mixture. Attempts have been made to explainthe nature of the products resulting from ring cleavage of sugar epoxides.For alkaline reagents and with an equatorial 6-hydroxymethyl group the'* L.Rebenfeld and E. Pacsu, J . Amer. Chem. SOC., 1953, 75, 4370.50 A. C. Hulme, Natuve, 1953, 171, 610.61 G. P. McSweeney, L. F. Wiggins, and D. J. C. Wood, J., 1952, 37.52 F. H. Newth and (in part) R. F. Homer, J., 1953, 989.53 V. Y. Labaton and F. H. Newth, J., 1953, 992.54 J. W. H. Oldham and G. J. Robertson, J., 1935, 685.5 5 G. N. Richards and L. F. Wiggins, J., 1953, 2442.56 A. B. Foster, W. G. Overend, M. Stacey, and G. Vaughan, J.. 1953, 3308.REP.-VOL. L 258 ORGANIC CHEMISTRY.preponderant isomer from the 2 : 3-anhydro-sugars is that which has theentering substituent in the polar ~onfiguration.~~ I t has been emphasised,58however, that in the present state of knowledge it is unsafe to presupposethe conformation of a monocyclic product resulting from epoxide fission.CH2 9 H r?o,HPhCH-0 (-1 OMe I I+ .:,I PhCH-0 ]Tl;:g 1-1 OMe(V) H H Et H (VI)That results in this field are still somewhat empirical is illustrated by theunexpected finding 59 that whereas treatment of methyl 2 : 3-anhydro-~-lyxofuranoside with sodium methoxide and subsequent hydrolysis affords2-O-methyl-D-xylose (1 part) and 3-O-methyl-~-arabinose (2 parts), similartreatment of the 5-O-methyl ether of the anhydropentoside gives only2 : 5-di-O-methyl-~-arabinose, no xylose derivative being detectedThe highlight of the year in sugar chemistry, undoubtedly was the chemicalsynthesis of sucrose.60 Dry tri-O-acetyl-D-glucosan<l : 5>a<l : 2>(1 : 2-anhydro-3 : 4 : 6-tri-O-acetyl-a-~-glucose) 1 : 3 : 4 : 6-tetra-O-acetyl-D-fructofuranose were heated together in a sealed tube at 100" for4 hours.Sucrose octa-0-acetate was isolated by Lo y--AC standard procedures in very low yield (56%) and onde-acetylation afforded sucrose. Likewise, maltoseocta-0-acetate was prepared (8% yield) by reaction ofAcO 1 H the anhydride with 1 : 2 : 3 : 6-tetra-O-acetyl-p-~-W1) glucopyranose 61 and subsequent further acetylation,etc. I t is believed that the 1 : 6-p-~-cyclic ion (VII) is formed as an inter-mediate in reactions of the Brig1 anhydride with alcohols at elevatedtemperatures.Methods have been described for the preparation of anhydro-compounds.andCH,\/I G A C T/'OHHOBz H(VIII)/"-\ OH H (IX)HCH,*OEIHO 1-1 EIOH H (XI1-Fluoro-p-D-glucose with barium hydroxide gives 1 : 6-anhydro-~-glucose.62Reduction of tetra-0-benzoyl-p-D-fructopyranosyl bromide (VIII) withlithium aluminium hydride affords a small amount of 1 : 5-anhydro-~-I 7 A. K. Bose, D. K. R. Chaudhuri, and A. K. Bhattacharyya, Chem. and Ind.,59 E. E. Percival and R. Zobrist, J . , 1953, 564.60 R. U. Lemieux and G. Huber, J . Amer. Chem. SOC., 1953, 75, 4118.61 R. U. Lemicux, Canad. J . Chem., 1953, 31, 949.62 F. Micheel and A. KIemer, Chem. Bcr., 1952, 85, 187.1953. 869. 5* F. H. Newth, ibid., p. 1257OVEREND : CARBOHYDRATES. 259mannitol (IX) together with a new hexitan as the major prcduct. This wasidentified as 1 : 5-anhydro-~-gulitol (X) .63The nature and yields of the products resulting from the action of coldconcentrated hydrochloric acid on L-sorbose 64 are similar to those for thetwo main products from the analogous reaction with D-fructose. Theseproducts have been designated diheterosorbosans I and I1 and shown to berespectively di-L-sorbopyranose 2 : 1'-2' : l-dianhydride (XI) and mostprobably L-sorbofuranose-L-sorbopyranose 2 : 1'-2' : l-dianhydride (XII) .From this reaction with fructose, in addition to diheterolevulosan I and 11,H OH HHO ~!--O,JH,--O 3'1 14r OH !/I \/A7&\lv (XI)A T q [ q O < H +\o-i[kOH H Ha new crystalline dianhydride has been isolated 65 which apparently is eitherdi-D-fructopyranose 1 : 2'-2 : 3'-dianhydride, or, more probably, an anomericform of diheterolevulosan 11.H OH HH /"\ 1\/H-o\/HTGo\ I i O H (XII)HO*H,C K H 1-1 ""/\o-~/\o-"/l l HOH H H HDeoxy- and Branched-chain Sugars.-A new deoxy-sugar, boivinose, hasbeen obtained by hydrolysis of a glycoside obtainable from Roupelinaboivini Pichon (Strophanthus boivini Bai11).66 I t has been identified as 2 : 6-dideoxy-D-xylohexose and its synthesis achieved.67 The conversion ofanhydro-sugars of ethylene oxide type directly into deoxy-sugars by treat-ment with lithium aluminium hydride has been exploited. Coupled withconventional sugar reactions methyl 2 : 3-anhydro-4 : 6-di-O-tosyl-a-~-alloside has been converted by this method into digitoxose and cymarose.68Reductive elimination of toluene-P-sulphonyloxy-groups can also beachieved by this reagent and treatment of 3 : 5-O-benzylidene-1 : 2-O-iso-propylidene-6-O-tosyl-~-glucofuranose and 1 : 2-0-isopropylidene-3 : 5-di-0-t osyl-D-xylofuranose affords derivatives of 6-deoxy-~-glucose (D-gluco-methylose) 69 and 5-deoxy-~-xylose (D-xylomethylose) 70 respectively.Thereactivity of groups in a sugar molecule towards the reagent is : anhydro-ring > primary tosyl ester > secondary tosyl ester.71Currently, attention is focused on the physiological action of 2-deoxy-D-glucose, especially as an inhibitor and antagonist of glucose,72 and so the63 R. K. Ness and H. G. Fletcher, jun., J . Amer. Chem. SOL, 1953, 75, 2619.64 M. L. Wolfrom and H. W. Hilton, ibid., 1952. 74. 5335.e 5 M. L. Wolfrom, H.W. Hilton, and W. W. Binkley, ibid., p. 2867.66 0. Schindler and T. Reichstein, Helv. Chim. Acta, 1952, 35, 730.6 7 H. R. Bolliger and T. Reichstein, ibid., 1953, 36, 302.6 8 H. R. Bolliger and P. Ulrich, ibid., 1952, 35, 93.69 P. Karrer and A. Boettcher, ibid., 1953, 36, 570.70 Idem, ibid., p. 837. 71 H. R. Bolliger and M. Thiirkauf, ibid., 1952, 35, 1426.72 F. B. Cramer and G. E. Woodward, J . Franklin Inst., 1052, 253, 354; J. 0. Ely,F. A. Tull, and J. A. Hard, ibid., p. 361; M. H. Ross and J . G. Archer, ibid., p. 525;G. E. Woodward, ibid., 1952, 254, 553 ; G. E. Woodward and F. R. Cramer, ibid., p. 259260 ORGANIC CHEMISTRY.glycal reaction for its preparation has been re-investigated. 73 Besidesyielding 2-deoxy-sugars, the reaction also affords furan derivatives. Meth-anolic hydrogen chloride and D-glUCal gave not only methyl 2-deoxy-ap-D-glucoside but other substances also, amongst which Z-hydroxymethyl-5-methoxymethylfuran was recognised.74 Of interest, was the conversionof D-glucose into %deoxy-~-xylose. 75 1 : 2-5 : 6-Di-O-isopropylidene-3-0-tosyl-D-glucofuranose was converted into 3-deoxy-1 : 2-5 : 6-di-O-isopropyl-idene-D-glucoseen (XIII) which on reduction and hydrolysis yielded 3-deoxy-D-galactose (XIV). The oxime of (XIV) on treatment with l-fluoro-2 : 4-dinitrobenzene in weakly alkaline solution gave the lower aldose, i.e.,2-deoxy-D-xylose.0A method is still sought for the synthesis of 2-deoxy-D-ribose in goodyield. Partial oxidation of 3-deoxy-~-g~ucose with periodate followed bydeformylation 76 gave some deoxypentose 77 (29% yield).Arabinose washeated in pyridine and converted into ribulose which was isolated as itso-nitrophenylhydrazone and reduced as such to the 2-amino-2-deoxy-pentitols. These were converted into 2-deoxyribose (3% overall yield) bytreatment with nitrous acid.78 To the Reporter the explanations proposedfor the reactions involved do not seem plausible. Application of the im-proved 79 Ruff method of degradation to calcium dextromet asaccharinateyielded 2-deoxy-~-ribose. Since carbohydrate precursors give poor yieldsof the deoxypentose an attempt has been made to build up the molecule fromsimpler units. 81 Allylmagnesium bromide and 2 : 3-O-isopropylidene-~-glyceraldehyde react to give 1 : 2-isopropylidenedioxyhex-5-en-3-01, appar-ently containing largely the erythro-isomer.Hydroxylation of this, followedby periodate oxidation and hydrolysis, afforded 2-deoxy-D-ribose, in pooroverall yield. Deoxyribose-5 phosphate has been synthesised enzymicallyfrom acetaldehyde and triose phosphate.82 There is a preliminary announce-ment 83 of the chemical synthesis of some phosphoric esters of 2-deoxy-L-ribose.Following the successful enzymic synthesis of 6-deoxy-~-fructose and-L-sorbose by addition of pea aldolase to DL-lactaldehyde and triose phos-phate 84 it has been shown that this enzyme converts triose phosphate and73 F. B. Cramer, J. F r a n k l i n I n s t . , 1952, 253. 277.74 F. Shafizadeh and M. Stacey, J ., 1952, 3608.75 F. Weygand and H. Wolz, Chem. Ber., 1952, 85, 256.7 6 G. R. Barker and D. C. C. Smith, Chem. and I n d . , 1052, 1035.7 7 P. A. J. Gorin and J. K . N. Jones, Nature, 1953, 172, 1051.79 H. G. Fletcher, jun., H. W. Diehl, and C. S. Hudson, J . Anzer. Chem. SOL, 1950,81 L. Hough, ibid., 1951, 406; J . , 1953, 3066.83 E. Racker, J . B i d . Chem., 1953, 196, 347; M. G. McGeown and F. H. Malpress,R. Allerton, W. G. Overend, and M. Stacey, Chem. and I n d . , 1952, 952.84 L. Hough and J . K. N. Jones, ibid., p. 715; J., 1952, 4052.Y. Matsushima and Y . Imanaga, ibid., 1953, 171, 475.72, 4546.Nature, 1952, 170, 575.G. N. Richards, Chem. and I n d . , 1953, 1035OVEREND : CARBOHYDRATES. 261acetaldehyde into 5-deoxyxylulose.85 Reductive desulphurisation of thediethyl mercaptal of the corresponding hexose 86 or pentose 87 leads to1 -deoxy-hexit 01s or -pentit 01s.The mechanism of formation of saccharinic acids has been studied with14C as a The action of lime-water on D-mannOSe and D-galactoseleads to the formation of " D-ghcosaccharinic acid " (XV) and " D-galacto-a-metasaccharinic acid " (XVI) respectively.Results obtained so farindicate that the branched-chain acid (XV) and the straight-chain acid (XVI)are formed by different mechanisms. (XV) is produced by a recombinationprocess, involving sugar fragments, the identity of which is not known withcertainty. Formation of (XVI) proceeds by a process of intra-molecularisomerisation and hydration, similar to the benzilic acid rearrangementmechanism, as suggested by Nef 89 and I ~ b e l l .~ ~C;O,H n:PMe nyHMe-OH H*O.COBui OQi:O." oG HH -HCH, CH,(XV) ( X V I ) (XVII) (XVIII)Methanolysis of the antibiotic " Magnamycin " 91 yielded a base and aneutral oil. Evidence presented 92 indicates that the neutral material 'isthe methyl 4-O-isovalerylglycoside (XVII) of a new branched-chain deoxy-sugar (XVIII), named mycarose. [The disposition of the groups in (XVII)and (XVIII) has no significance since the stereochemistry is not yet workedout.] The successful synthesis is reported s3 of cordycepose, a branched-chain sugar component of cordycepin, a metabolic product of Cordycefisrnilitaris (Linn.) Link.94 Another synthesis of a branched-chain sugar isdiscussed on p.258.Glycosylamines and Amino-Sugars.-1-Amino-derivatives of cellobioseand lactose are formed by the action of alcoholic ammonia (at high tem-perature and under pressure) on these sugars.95 D-Psicose, 4(5)-rnethyl-glyoxaline, and 2-methyl-5- and 2-methyl-6( ?)-(D-arabotetrahydroxybuty1)-pyrazine have been obtained from the complex mixture resulting fromtreatment of D-glUCOSe with aqueous ammonia.96 Lactose and maltose areisomerised in aqueous ammonia to lactulose and maltulose and also undergoalkaline fissi0n.~7 A general method has been devised for preparing, ascharacteristic derivatives, the crystalline N-P-tolylglycosylamines of theF M-V-OHH T - O HHY-OHH2L:HCH,.OH85 P. A. J. Grin, L. Hough, and J. K. N. Jones, J., 1953, 2140.8G E.Zissis and N. K. Richtrnyer, J . Amev. Chenz. Soc., 1952, 74, 4374.8 7 Idem, ibid., 1953, 75, 129.J. C. Sowden and D. J . Kuenne, ibid., p. 2788.89 J. U. Nef, A n n a l e n , 1907, 357, 294; 1910, 376, 1.B0 H. S. Isbell, J . R e s . Nut. Bur. Stand., 1944, 32, 45.B1 R. L. Wagner, jun., F. A. Hochstein, K. Murai, N. Messina, and P. P. Regna,B2 P. P. Regna, F. A. Hochstein, R. L. Wagner, jun., and R. B. Woodward, ibid.,94 H. R. Bentley, K. G. Cunningham, and F. S. Spring, J . , 1951, 2301.95 F. Micheel, R. Friei, E. Plate, and A. Hiller, Chem. Ber., 1952, 85, 1092.B6 L. Hough, J. K. N. Jones, and E. L. Richards, J., 1952, 3854.97 I d e m , J., 1953. 2005.J . Amer. Chern. SOC., 1953, 75, 4685.p. 4626. 93 R. A. Raphael and C . M. Roxburgh, Chem. and I n d ., 1953, 1034262 ORGANIC CHEMISTRY.common aldoses (except L-arabinose) .98 The influence of moisture on theformation of the two isomeric N-phenyl-D-ribosylamines has been estab-l i ~ h e d . ~ ~ By using anhydrous reactants new labile isomers of N-+-tolyl-D-glucosylamine and -D-galactosylamine were prepared.98 N-Substitutedglycosylamines have been derived from sulphanilamide and $-aminosalicylicacid.99 It is claimed that no solvent or catalyst is necessary for the pre-paration of glycosyl derivatives of highly basic amines.lOO Investigations,lOlin the glucose series, of the transglycosylation reaction, whereby the aryl-amine residue in a N-substituted aldosylamine is replaced by anotherarylamine, i.e.,Ar‘aNH,Ar-NH- H.[CH(OH)] *CHCH,.OH h4 Y-o”’Ar’*NH*CH-[CH (OH)] H*CH,*OH + Ar-NH, LoAhave revealed that the reaction depends on pH and in certain circumstancesis reversible.Solubilities of reactants and of possible products play a partin the change, which undoubtedly is transglycosylation rather than hydro-lysis followed by redistributive reglycosylation. Tetra-O-acetylglucosyl-amines also undergo this reaction. Piperidine with either a- or p-D-glUC0-pyranose penta-0-acetate affords N-D-glucosylpiperidine 3’ : 4’ : 6’-tri-O-acetate, deacetylation occurring at Ctl, and Ce,. The same tri-0-acetate isobtained by adding piperidine to either 3 : 4 : 6-tri-O-acetyl-D-g~ucosylchloride or D-glucose 2 : 3 : 4 : 6-tetra-O-acetate. Loss of acetyl a t Ct2>must accompany or precede formation of the C-N bond since N-D-glUCOSY1-piperidine 2’ : 3’ : 4’ : 6’-tetra-O-acetate is unaffected by piperidine.lo2The reaction of ammonia with a-D-glucose penta-0-benzoate to produceD-ghCOSe dibenzamide lo3 has been found lo4 to be of general application tothe acetates and benzoates of the monosaccharides; a series of competitivereactions is involved.There is now available an improved method for synthesising N-phenyl-and N-P-tolyl-D-fructosylamine and well-characterised cdmpounds have beenobtained for the first time.105 Unlike the corresponding glucosylamines,these are stable for years.Other N-substituted fructosylamines have beenprepared,1°6 but not in good yield. In the presence (but not in the absence)of warm dilute alcoholic hydrochloric acid, aldohexoses react with long-chain alkylureas.107 Ketohexoses do not react even in the presence ofacid.lo7 Ketoses condense more readily than aldoses with aliphatic amines.losReactions with long-chain primary aliphatic amines can go far past theamine-glycoside stage and solids of uncertain structure are formed byreaction of 4 - 5 molecules of amine with one of glucose or sorbose.lo8 Thestabilities and behaviour in solutions of N-arylglycosylamines have attracted98 G.P. Ellis and J. Honeyman, J.. 1952, 1490.g9 R. Bognar and P. NQnQsi, J., 1963, 1703.lo0 J. E. Hodge and C. E. Rist, J . Amer. Chem. Soc., 1952, 74, 1494.lol R. Bognar and P. NBnBsi, Nature, 1953, 171, 475.Io2 J. E. Hodge and C. E. Rist, J . Amer.Chem. Soc., 1952, 74, 1498.lo3 V. Deulofeu and J. 0. Deferrari, Nature, 1951, 167, 42.Io4 Idem, Chenz. and Ind., 1952, 272; J . Org. Chem., 1952, 17, 1087, 1093, 1097.lo5 C. P. Barry and J. Honeyman, J., 1952, 4147.lo6 B. Helferich and W. Portz, Chem. Ber., 1953, 86, 604.lo’ J. G. Erickson and J. S. Keps, J . Amer. Chem. SOC., 1953, 75, 4339.lo8 J. G. Erickson, ibid., p. 2784OVEREND : CARBOHYDRATES. 263attention. The stability of N-arylglucosylamines increases in the order,N-phenyl- , -P-tolyl-, -m-tolyl-, -o-tolyl.109 Amongst the N-chlorophenyl-and N-carboxyphenyl-glucosylamines, the ortho- are more stable than themeta- and the ;barn-isomers.lOg In weakly acidic solutions the ortlzo-com-pounds are the least readily converted into the corresponding isoglucos-amines.log The amounts of water and acid present are amongst the majorfactors involved in the darkening of methanolic solutions of N-phenyl-D-glucosylamine.l10 Atmospheric oxygen and the darkening of possiblehydrolysis products (glucose and aniline) do not contribute significantly tothe colour development. Darkening occurs rapidly in hot alcoholic solutionscontaining also compounds having active methylene hydrogen atoms-lllThe Amadori rearrangement isomer is amongst the products of darkeningof a glycosylamine.lllExamination of the chromatographic behaviour of 2-deoxy-N-P-tolyl-D-galactosylamine and its D-galactosyl analogue indicated that considerablehydrolysis occurs in aqueous solvents,112 and other studies 113 have shownthat glycosylamines may undergo rapid hydrolysis or isomerisation inaqueous solutions.Hydrolysis may only be partial a t equilibrium. Whencarefully purified, D-glucosylpiperidine does not mutarotate ill dry pyridine,but mutarotation was observed in this solvent with D-mannosyl- and D-galactosyl-piperidine.lOO Since in this solvent the production of a cationby the mechanism postulated by Kuhn and Birkofer 114 cannot be expected,it was suggested that an intramolecular rearrangement may have takenplace and there is some evidence for this with the mannose derivative.lWO-Methyl ethersJ1l5? 116 O-acetates,lO2? ll5? 117 and O-benzoates 115 of N-sub-stituted glycosylamines have been studied. Browning of solutions of thetetra-@acetates of N-phenyl-D-glucosylamine is much slower than forN-phenyl-D-glucosylamine but occurs eventually.l18 Acid hydrolysis of~-~-to~yl-~-D-g~ucosy~amine 2 : 3 : 4 : 6-tetra-O-acetate gives glucose2 : 3 : 4 : 6-tetra-O-acetate.115 For the preparation of such acetates this isan attractive alternative method to the use of the aldosylbromide acetate.It has been extended to the ketose series.In these reactions the N-aryl-glycosylamines behaved as pyranose compounds. The infra-red spectra ofsolid N-o-tolyl- and N-p-naphthyl-D-glucosylamine have been interpreted asindicating that these compounds have a Schiff-base structure,119 but theirelucidation is not yet complete.Addition of thiosemicarbazide or isonicotinoylhydrazine, or a number ofother reagents, to periodate-oxidised starch yielded polymeric productscontaining nitrogen,120 but there was only one molecule of base per hexoseunit.The aldehyde functions of the oxyhexose units are apparently modi-log S. Bayne and W. H. Holms, J . , 1952, 3247.110 L. Kosen, K. C. Johnson, and W. Pigman, J . Amer. Chem. SOC., 1953, 75, 3460.111 J. E. Hodge and C. E. Rist, ibid., p. 316.112 J. L.Barclay, A. B. Foster, and W. G. Overend, Chem. and Ind., 1953, 462.113 W. Pigman, E. A. Cleveland, D. H. Couch, and J. H. Cleveland, J. Amer. Chenz.115 G. P. Ellis and J . Honeyman, J., 1952, 2053.116 I. Ehrenthal, M. C. Rafique, and F. Smith, J . Amer. Chem. SOC., 1952, 74, 1341.11' J. Honeyman and A. R. Tatchell, J . , 1950, 967.11* W. Pigman and K. C. Johnson, J . Amer.Chem. SOC., 1953, 75, 3464.119 F. Legay, Compt. rend., 1952, 234, 1612.lZo V. C. Barry and P. W. D. Mitchell, J . , 1963, 3610.SOC.. 1951, 73, 1976. 114 R. Kuhn and L. Birkofer, Ber., 1938, 71, 621, 1535264 ORGANIC CHEMISTRY.fied and it is suggested 121 that they are united in a " hemialdal " linkage(cf. Hurd et ~ ~ 1 . l ~ ~ ) to give a seven-membered cyclic unit which reacts withthe base as shown.---7 I ---? yii EG*OH i !NH,RI - _ _ _ - L--- yq H.0 j - H,OH2*OH H2.0HSome of the non-enzymic browning which occurs in foods during concen-tration, dehydration, or storage can be attributed to reactions between re-ducing sugars and amino-compounds 123 (the Maillard reaction). Accordingto Hodge and Rist ll1 this non-enzymic browning can occur by condensationof reducing sugars and amino-compounds to form glycosylamines. Theserearrange spontaneously to deoxyaminoketoses which are dehydratedspontaneously to nitrogenous reductones.[The labile deoxyaminoketoses(via their scission and/or dehydration products) produce the Streckerdegradation of amino-acids, forming aldehydes and carbon dioxide.] Thenitrogenous reductones react slowly alone (in the presence of air) and rapidlywith amino-acids to produce brown pigments. For browning reactionsbetween amino-acids (glycine and alanine) and a reducing sugar (D-xylose)it is reported 124 that there is strong base-catalysis between the initial pHvalue of 6.5 and 8.5, solvent or weak base-catalysis between values of 3and 5, and acid inhibition in the range 1-3.The nature of the repeatingunit of browning polymers has been probed by radioactive tracertechniques.125 The rates of browning with glycine of the well-characterisedhexose phosphates of the glycolytic cycle have been rneasured.lz6 Thepresence of a phosphate ester at the primary alcohol group of both glucoseand fructose increases the rate of browning : there was no browning withglycosidic phosphate esters. The kinetics of the reaction between variousaldoses and amino-acids and peptides have been examined.12' The reactionof glucosamine with casein differs fundamentally from that of glucose.128There are recent accounts of the synthesis of 3 : 6-di-O-methyl-N-methyl-~-glucosamine,l29 and acetylated thioacetals of ~-glucosamine, 130 of the cata-lytic oxidation of glucosamine to glucosaminic acid,l31 and of the preparationof acyl derivatives of the acid.132 Experiments on the preparation of a- 133and p-glycosides 134 of N-acetylglucosamine have been reported.Reaction121 V. C. Barry and P. W. D. Mitchell, J . , 1953, 3631.122 C. D. Hurd, P. J. Baker, jun., R. P. Holysz, and W. H. Saunders, jun., J . Org.123 J. P. Danehy and W. Pigman, Adv. Food Res., 1951, 3, 241.124 M. L. Wolfrom, D. K. Kolb, and A. W. Langer, jun., J . Amer. Chem. Soc., 1953,125 M. L. Wolfrom, R. C. Schlicht, A. W. Langer, jun., and C. S. Rooney, ibid.,127 A. Katchalsky and N. Sharon, Biochim. Biophys. Acta, 1953, 10, 290.128 C. H. Lea and D. N. Rhodes, ibid., 1952, 9, 56.lZ9 J. Fried and D. E.Walz, J . Amer. Chem. SOC., 1952, 14, 5468.130 M. L. Wolfrom and K. Anno, ibid., p. 6150.131 K. Heyns and W. Koch, Chem. Ber., 1953, 88, 110.132 M. L. Wolfrom and M. J. Cron, J . Amey. Chem. Soc., 1952, 14, 1715.133 R. Kuhn, F. Zilliken, and A. Gauhe, Chem. Ber., 1953, 86, 466.134 R . Kuhn and H. H. Baer, ibid., p. 724; R. Kuhn and W. Kirschenlohr, ibid.,Chem., 1953, 18, 186.'45, 3471.p. 1013. 126 S. Schwimmer and H. S. Olcott, ibid., p. 4855.p . 1331OVEREND CARBOHYDRATES. 265of 1 : 3 : 4 : 6-tetra-O-acetyl-p-~-g~ucosamine with acylamino-acid chloridesaffords derivatives of D-glucosamine substituted on the nitrogen atom byacylamino-acid residues (i.e., “ gluco-peptide ” acetates).135 When anattempt was made 136 to acylate 1 : 3 : 4 : 6-tetra-O-acetyl-p-~-glucosamineby use of acylamino-acid azides, Curtius rearrangement took place in everycase. In the presence of aqueous sodium nitrite methyl a- and p-D-glucos-aminide hydrochloride were rapidly deaminated, but at different rates.13’The p-isomer reacted most rapidly, but in each case 2 : 5-anhydro-~-mannosewas the main product. I t was suggested that deamination of the a-formmay be hindered by the single axial group at the glycosidic centre and bythe cis-1 : 2-relation of the methoxyl and the amino-group. The influenceof the configuration of the glycosidic centre in glucosaminides on the rate ofdeamination may be of use in establishing the configuration of glucos-aminidic linkages in certain mucopolysaccharides.Two aminodeoxypentoses have been synthesised, namely, 2-amino-2-deoxy-D-xylose 138 (D-xylosamine) (XXII) and 3-amino-3-deoxy-~-ribose 139(XXIII) (both isolated as the hydrochloride).The former was obtainedby using ethyl 2-acetamido-2-deoxy-a-~-gIucothiofuranos~de (XIX) as theinitial material by submitting it to gIycoI cleavage with sodium meta-periodate and then reducing the product (XX) with sodium borohydrideto ethyl 2-acetamido-2-deoxy-a-~-xylothiofuranoside (XXI) from whichH NHAc H NHAc H NHAc H NH,( X W (XX) (XXI) (XXII)(XXII) was obtained by complete hydrolysis. The ribose derivative(XXIII) was synthesised as follows. (a) Methyl 2 : 3-anhydro-p-~-ribo-pyranoside was converted into methyl 3-amino-3-deoxy-~-~-xylopyranosideby heating it with aqueous ammonia.(b) Acetylation and subsequentmethanesulphonylation yielded methyl 3-acetamido-3-deoxy-2 : 4-di-0-methanesulphonyl-p-L-xylopyranoside. (c) This on treatment with boilingalcoholic sodium acetate and further acetylation afforded methyl 3-acet-amido-2-0-acetyl-3-deoxy-4-0-methanesulphonyl-~-~-lyxopyranoside. Re-petition of the process with 95% boiling “ Methyl Cellosolve ’’as solvent gave methyl 3-acetamido-2 : 4-di-0-acetyl-3-deoxy- ,OHa-D-ribopyranoside. Elimination of the methanesulphonyl re-sidues is accompanied by inversion and is reported to occur viaan oxazoline. (d) Hydrolysis furnished 3-amino-3-deoxy-~-ribose (XXIII), identical with the amino-pentose obtained as(xxlll) one of the hydrolysis products of “ Achromycin.” l40 It is note-worthy that this synthesis proceeds through all four pentose configurations.135 D.G. Doherty, E. A. Popenhoe, and K. P. Link, J . Amer. Chem. SOC., 1953,75,3466.136 E. A. Popenhoe, D. G. Doherty, and K. P. Link, zbid., p. 3469.137 A. B. Foster, E. F. Martlew, and M. Stacey, Chem. and Ind., 1953, 825.138 M. L. Wolfrom and K. Anno, J . Amer. Chem. SOC., 1953, 75, 1038.139 B. R. Baker and R. E. Schaub, i b i d . , p. 3864.140 C. W. Waller. P. W. Fryth, B. L. Hutchings. and J. H. Williams, ibid., p. 2025266 ORGANIC CHEMISTRY.Miscellaneous.-A new method of descent 141 in the aldose series in-volves oxidation of the diethyl mercaptal (XXIV) of the aldose acetate withmonoperphthalic acid in ether. Treatment of the main product (XXV) withhydrazine in methanol gives the lower aldose (XXVI) and bisethane-sulphonylmethane in good yield.p W W 2 ~ ( S O Z W , CH2( SO,*Et),K (XXIV) "2 (XXV) RCHO (XXVI)FH*OAc + + +Cation-exchange resins are effective in promoting the formation ofglycosides from pentoses, hexoses, uronic acids, and methylated sugars, andof isopropylidene derivatives of sugars and methyl g1y~osides.l~~ A newsynthesis of p-glucopyranosides has been outlined.143A convenient preparative method for polyols is to reflux aldoses andketoses in aqueous alcohol with Raney n i ~ k e 1 . l ~ ~ Sodium borohydride hasbeen used 145 in reductions in the sugar series. Chlorine-water oxidation ofanomeric pairs of methyl glycosides proceeds most readily with theP-isomer.lQ6 An interesting new method for masking the hydroxyl groupsat Sugar nitrates can beprepared by treatment a t 0" of a suspension of the sugar derivative in aceticanhydride, with acetic anhydride and ca.50% excess of fuming nitric acid.lQsThe syntheses and properties of some nitrate esters of alkyl D-glucosideshave been described.149 Syntheses of fructose-1 phosphate,150 a- andp-lactose-1 phosphate,151 a-D-mannose-1 and -6 phosphate, and -1 : 6 di-phosphate,152 and glucose-6 phosphate 153 have been described. Hydro-lysis of glucose-4 phosphate 154 and fructose-6 phosphate 155 has beenstudied.Rules have been published 156 which enable the condensation productsof polyhydric alcohols with acetaldehyde, benzaldehyde, and formaldehydeto be predicted.A detailed analysis has been made 157 of the stereochemicalfactors governing the synthesis of acetals of polyhydric alcohols.Solvolytic reactions of tetra-0-acetyl-a-D-glucopyranosyl 1-bromide havebeen examined kinetically.158a The reactivity of the halogen in the O-acyl-141 D. L. MacDonald and H. 0. L. Fischer, J . Aiizcr. Chem. SOC., 1952, 74, 2087;Biochem. Biophys. Acta, 1953, 12, 203.142 W. H. Wadman, J., 1952, 3051 ; J. E. Cadotte, F. Smith, and D. Spriestersbach,J . Amer. Chem. Soc., 1952, 74, 1501.143 R. U. Lemieux and W. P. Shyluk, Canad. J . Chem., 1953, 31, 528.144 J . V. Karabinos and A. T. Ballun, J . Amer. Chem. SOC., 1953, 75, 4501.145 M. L. Wolfrom and K. Anno, ibid., 1952, 74, 5583; L. Hough, J . I<. N. Jones,and E. L. Richards, Chcm.and Iwd., 1953, 1064; A. Meller, Chem. and Ind., 1953, 1204.146 B. Lindberg and D. Wood, Acta Chem. Scand., 1952, 6, 791.147 B. Helferich and E. von Gross, Chem. Ber., 1952, 85, 531.148 J . Honeyman and J. W. W. Morgan, Chem. and Ind., 1953, 1035.G. H. Williams, Chem. and Ind., 1952, 149; D. M. Shepherd, J., 1953, 3635.I5O B. M. Pogell, J . Bid. Chem., 1953, 201, 645.151 F. J. Reithel and R. G. Young, J . Amer. Chem. Soc., 1952, 74, 4210.152 T. Posternak and J. P. Rosselet, Helv. Chim. Acta, 1953, 36, 1614.153 M. Viscontini and C. Olivier, ibid., p. 466.154 H. R. Dursch and F. J. Reithel, J . Amer. Clzem. Soc., 1052, 74, 830.155 S. L. Friess, J . Amer. Chzm. SOC., 1952, 74, 5.521.15G S. A. Barker and E. J. Bourne, J., 1952, 905.l S 7 S.A. Barker, E. J. Bourne, and D. H. Whiffen, J., 1952, 3865.158 F. H. Newth and G. 0. Phillips, ( a ) J., 1053, 2896, (b) 2900, ( G ) 2904.and C(,) in aldopyranoses has been 0ut1ined.l~~E. G. Ansell and J. Honeyman, J., 1952, 2778; E. G. Ansell, J . Honeyman, anDVEREND : CARBOHYDRATES. 267glycosyl l-halides is due to its being part of an a-halogeno-ether system.1586The methanolysis rate of the halides is directly proportional to the amountof " crowding " about C(1).158cAs far as can be judged a t present arabitol occurs in all lichens of theorder Gyvnnocarpeae, but not in the lichens of the genera Dermatocarpon andE n d o c a ~ p o n . ~ ~ ~ These however contain volemitol which is not detectable inGymnocarpeae. Mannitol was found in all the lichens investigated and,amongst other components, umbilicin (3-~-arabitol p-D-galactopyr-anoside lc0), aa-trehalose, and sucrose were also detected.161 From thebrown alga Fucus vesicuZosus, D-mannitol l-0-acetate, D-mannitol 1 - @ - ~ -glucopyranoside, and D-mannitol 1 : 6-di-( p-~-glucopyranoside) have beenisolated,162 and the first two ~ y n t h e s i s e d .~ ~ ~ There is continued interest inthe synthesis of sugars from simple precursors in ~ i t r 0 . l ~ ~Po1ysaccharides.-An extensive survey 165 on the enzymic synthesisof polysaccharides concludes by stating that the problems of immediateinterest are the syntheses of pentosans, @-glucosans, mannans, and otherpolysaccharides containing essentially a single sugar component : in thesecases it will be necessary to consider how both the branched and the un-branched portions of the molecules arise.The biological significance andvarious chemical aspects of bacterial polysaccharides have been reviewedby Stacey,166 who has also surveyed the rdle of carbohydrates in immuno-chemistry. 167 Blom and Schwartz's conclusion 168 that molecules of starchcontain, in addition to the generally accepted or-1 : 4- and a-1 : 6-gluco-pyranosidic linkages, an additional type of glucosidic linkage has beencritically but concisely examined by Hopkins 169 who believes that it createsmore difficulties than it clears up; Lindberg 170 has also criticised the sug-gestion. During the past year there has been a symposium on " BiologicalTransformations of Starch and Cellulose " 171 and some of the meetings a tthe XIIIth International Congress of Pure and Applied Chemistry 172 weredevoted to cellulose chemistry.Publication of a textbook on " Poly-saccharide Chemistry" by R. L. Whistler and C. L. Smart 173 fills a long-standing gap.W. G. 0.IsQ B. Lindberg, A. Misiorny, and C. A. Wachtmeister. Acta Chem. Scand., 1953, 7 ,l80 B. Lindberg, C. A. Wachtmeister, and B. Wickberg, ibid., 1952, 8, 1052.lC1 B. Lindberg and B. Wickberg, ibid., 1953, 7 , 140.16* B. Lindberg, ibid., p. 1119.lb3 Idem, ibid., pp. 1123, 1218.164 L. Hough and J. K. N. Jones, J., 1952, 4047; J., 1953, 342; Chem. and Ind.,1b5 S. A. Barker and E. J . Bourne, Quart. Reviews, 1953, 7 , 56.167 I d e m , Biochem. SOC.Symp., No. 10, 1953.168 J. BIom and B. Schwarz, Acta Chenz. Scand., 1952, 6, 697.lGQ R. H. Hopkins, Il'ature, 1953, 171, 429.170 B. Lindberg, Acta Chenz. Scand., 1953, 7 , 237.171 Biochem. SOC. Symp., No. 11, 1953.172 Abst. of Papers, XI11 Int. Congr. Pure Appl. Chem., 1953, Group 22, p. 225,173 Academic Press, Inc., New York, 1953.501.1952, 907; P. A. J. Gorin and J . K. N. Jones, J., 1953, 1537.M. Stacey, Discovery, 1953, p. 271; Endeavour, 1953, 12, 38; Reseavch, 1953,0, 159268 ORGANIC CHEMISTRY.9. PEPTIDES, PROTEINS, AND AMINO-ACIDS.Oxytocin and Vasopressin.-These hormones can now be obtained pure.I t is possible to extract both hormones simultaneously from beef hyophyses ;their further purification involves similar methods for each.2 Bovine vaso-pressin can be purified by zone electrophoresis and is readily separated fromoxytocin (I) under these condition^.^ Bovine oxytocin can be obtained pureby counter-current distribution and, although itself non-crystalline, ityields a crystalline flavianate with specially purified flavianic acid.4 Bovineand porcine oxytocins appear to be identical in ~hemical,~ phy~ical,~ andbiological properties. The structure of oxytocin has been announcedalmost simultaneously from two separate laboratories.In the first G,partial hydrolysis with hydrochloric acid and the plakalbumin-formingenzyme from B. subtilis formed the basis of the investigations. The secondgroup used a variety of methods8CyS.Tyr.Ileu*Glu (NH,) -Asp (N H,) CyS.Pro.Leu.Gly( NH,)Investigations into the structure of these hormones have indeed bornea rich harvest in 1953 for, in addition to oxytocin, the structure of arginine-vasopressin (11) has been announced from two sources.g- lo An additionalform of the hormone, lysine-vasopressin, has an identical structure, withlysine replacing the a~-ginine.~CyS*Tyr*Phe.Glu (NH2).Asp(NH,).Cy7.Pro.Arg*Gly(NH,)Final confirmation of the validity of these investigations comes fromthe synthesis of oxytocin and probably that of lysine-vasopre~sin.~ Thiswork will surely rank as one of the greatest achievements in peptide chemistryfor many years.Lack of space precludes a detailed description of themethods used, but a feature of major interest must be mentioned. This isa novel and simple synthesis of glutamine and glutaminyl peptides (annexedscheme).HO2C.CHzCHz*qH*COzH pcI, HZY-VH, R C H (NH *)-CO,KOC\ /CH*coC1 - NHsTs +N-TsHZy-qH2 Aq,NH, qH2--CH2-YH*CO*NH.~H*CO2HOC CH*CO*NH.CHR*COzH -e CO-NH, NH*Ts K(Ts = p-C,H,Me*SO,) \ /PIIT-Ts1 H.Maier-Huser, H. Clauser, P. Fromageot, and R. Plongeron, Biochim. Biofihys.3 S . P. Taylor, V. du Vigneaud, and H. G. Kunkel, J . Biol. Chem., 1953, 205, 45.4 J. G. Pierce, S. Gordon, and V. du Vigneaud, ibid., 1952, 199, 929.Acta, 1953, 11, 252. 2 P. Fromageot, R. Acher, and H. Clauser, ibid., 12, 424.H. G. Kunkel, S. P. Taylor, and V. du Vigneaud, ibid., 1963, 200, 559.H. Tuppy, Bzochinz. Biophys. Acta, 1953, 11, 449.H. Tuppy and H. Michl, Monatsh., 1953, 84, 1011. * V.du Vigneaud, C. Ressler, J. M. Swan, C . W. Roberts, P. G. Katsoyannis, andS. Gordon, J . Amev. Chem. SOC., 1953, 75, 4879; V. du Vigneaud, C. Ressler, and S.Trippett, J . Biol. Chem., 1953, 205, 949.V. du Vigneaud, H. C. Lawler, and E. A. Popenoe, J . Amer. Chem. SOC., 1953, 75,4881.lo R. Acher and J. Chauvet, Biochim. Biophys. Ada, 1953, 12, 487ELLIOTT PEPTIDES, PROTEINS, AND AMINO-ACIDS. 269Oxytocin can be reduced by sodium in liquid ammonia to the mercapto-form, which is readily re-oxidised to the parent substance in aqueous solutionin the presence of air. This is a striking demonstration of the feasibility ofinternal disulphide bridges in polypeptide chains; in fact, the ease withwhich it occurs suggests a very favourable disposition of the two thiol groups.This would be the case if the molecule were in the form of a spiral or foldedstructure.I t has been reported that anti-diuretic and oxytocic substances areliberated from plasma proteins by the action of pepsin,lll l2 but the identityof these substances has not been established.During their structural investigations on oxytocin and vasopressin duVigneaud and his collaborators have discovered a specific peptide-bondcleavage.13-15 This occurs between tyrosine and the amino-acid joined toits carboxyl group when the hormones or their performic acid oxidationproducts are treated with bromine water.The tyrosine residue is convertedinto a ring-dibromo-derivative.Bacitracin A.-This polypeptide has been obtained pure by counter-current distribution l6, 1' and by carrier displacement analysis.l8 The mole-cular weight is 1460 l8 or 1470 l9 and the amino-acid composition is : *OPhe Leu Ileu, CySH Glu Asp, His Lys Orn-NH,Preparative isolation of each amino-acid by counter-current distributionrevealed that the phenylalanine, glutamic acid, and ornithine had theD-configuration, the aspartic acid was racemic, and the remaining amino-acids had the L-configuration.It is generally agreed 1 9 3 217 22 that the mole-cule has a cyclic structure, but it presents certain very unusual features.When the amino-acid units and the ammonia are joined with loss of theminimum number of water molecules a molecular weight much lower thanthe experimental value is obtained. An estimation of the elements presentby combustion analysis is also in disagreement with the formulaC60H,,01,N16S.It is probable that a 5-carbon residue of unknown natureis present in addition to the amino-acids.19 In addition to the glyosalinenucleus the antibiotic contains two carboxyl groups and two basic groups,one of which is the &-amino group of ~ r n i t h i n e . l ~ * ~ l There is uncertaintyabout the identity of the second basic group. It has been claimed 21 thatit is the amino-group of leucine or isoleucine. On the other hand Porath 22could find no N-terminal a-amino-acid group by the fluorodinitrobenzenemethod or the Edman degradation (see also ref. 57). The E-amino-group oflysine is not free.lg> 21, 22 The nature of the linkage with the sulphur atomis not clear a t present.A positive thiol reaction is obtained from the anti-l1 H. Croxatto, L. Barnafi, G. Rojas, A. Reyes, and A. Infante, h'atuve, 1953, 171, 82.l2 H. Croxatto and L. Barnafi, ibid., 172, 306.13 J. M. Mueller, J. G. Pierce, and V. du Vigneaud, J . Biol. Chern., 1953, 204, 857.l4 C. Ressler, S. Trippett, and V. du Vigneaud, ibid., p. 861.l5 E. A. Popenoe and V. du Vigneaud, ibid., 1953, 205, 133.l6 L. C. Craig, J - R. Weisiger, W. Hausmann, and E. J. Harfenist, J . B i o l . Chem.,l7 G. G. F. Newton and E. I?. Abraham, Biochern. J., 1953, 53, 597.l9 L. C. Craig, W. Hausmann, and J. R. Weisiger, J . B i o l . Chem., 1953, 200, 765.2o L. C. Craig, W. Hausmann, and J. R. Weisiger, ibid., 1952, 199, 865.21 G. G.F. h'ewton and E. P. Abraham, Biochem. J . , 1953, 53. €04.22 J . Porath, N a t u r e , 1953, 172, 871.1952, 199, 359.J. Porath, Acta Chem. Scand., 1952, 6, 1237270 ORGANIC CHEMISTRY.biotic only after mild treatment with acid and as a working hypothesis thepresence of a thiazoline ring (111) is suggested.21, 22 This explains the form-ation of an amino-alcohol and an alanine residue with its amino-group freeon Raney nickel hydrogenolysis, but other observations are not so readilyinterpreted.21 Partial hydrolysis 22 indicates the sequence (IV) of amino-acid residues.R-Lys-C;lu-C$S-Ileu-I;eu. . . NH.CHR.C/s-]Hz +SP The\r;-CH.CO.. . . Asp-His- Orn-Ileu(111) ( wThe Adrenocorticotrophic Hormones.-Several procedures have beenpublished for the preparation of highly active polypeptide material frompituitary glands, but the relation between these products is not yet clarified.A substance called corticotropin-B has been obtained in a highly purifiedstate from pepsin digests of partially purified pituitary extract from pigs.23-25Adsorption on oxycellulose, ion-exchange chromatography, and counter-current distribution were used.Amino-acid analysis and sedimentationstudies indicated a minimum molecular weight of 5000-7000.26 A value ofapproximately 23,000 has been found 27 for the adrenocorticotrophic hormoneof sheep.28 Chromatography on Amberlite XE 97,29 followed by counter-current distribution, of the crude hormone from hog pituitaries 30 yielded asubstance, which was apparently pure, called corticotropin-A. There is acertain amount of indirect evidence to suggest 29 that hormone preparationsfrom acid or pepsin digests of pituitary extracts may be hydrolysis productsof corticotropin-A, At present only 88.5% of the dry weight of this substancehas been accounted for by analyses.30 Degradative studies on cortico-tropin-A have been fairly extensive, the sequences Ser-Tyr andPro*Leu*Glu*Phe 32 having been found respectively at the amino- and thecarboxyl end of the molecule.Carboxypeptidase was used to determinethe latter sequence ; the presence of more than one polypeptide chain cannottherefore be excluded.An account of recent work on the chemistry and purifization of theadrenocorticotrophic hormone has appeared.33 The oxycellulose method ofpurification has been ~implified.~*Structure of Insulin.-The complete sequence of amino-acids in the A-chain of insulin has been worked This leaves only the positions ofthe amide groups and the disulphide bridges to be determined; the latter23 A.W. Bazemore, J. W. Richter, D. E. Ayer, J. Finnerty, N. G. Brink, and K.24 J . W. Richter, D. E. Ayer. A. W. Bazemore, N. G. Brink, and K. Folkers, ibid.,z 5 F. A. Kuehl, M. A. P. Meisinger, N. G. Brink, and K. Folkers, ibid., p . 1955.26 N. G. Brink, G. E. Boxer, V. C. Jelinek, F. A. Kuehl, J. W. Richter, and K.27 R. M. Mendenhall, Science, 1953, 117, 713.28 C. H. Li, H. M. Evans, and M. E. Simpson, J . Biol. Chenz., 1943, 149, 413.29 W. F. White and W. L. Fierce, J . Amer. Chem.SOC., 1953, 75, 245.30 W. F. White, ibid., p . 503.31 W. A. Landmann, M. P. Drake, and W. F. White, ibid., p. 4370.32 W. F. White, ibid., p . 4877.33 “ Recent Progress in Hormone Research,” Vol. VII, 1952, Chapters 1 and 2.34 K. J . Bartholomew, Proc. SOC. Exp. Biol. N.Y., 1953, 83, 334.35 F. Sanger and E. 0. P. Thompson, Biochem. J . , 1953, 53, 353, 366.Follters, J . Anzer. Chem. SOC., 1953, 75, 1949.p. 1952.Folkers, ibid., p. 1960ELLIOTT : PEPTIDES, PROTEINS, AND AMINO-ACIDS. 27 1problem may be very difficult to solve owing to the ease with which a mixtureof disulphides can undergo an interchange reaction.36 I t has been believedfor a long time that insulin consists of four chains and has a molecular weightof 12,000, but a recent determination by a novel method gives a value of6500.37 This method involves partial substitution of the reactive groupsin a molecule under conditions deliberately chcsen to prevent completereaction. The mixture of products is then submitted to counter-currentdistribution, the monosubstituted product being that found nearest to theparent substance. If a suitable substituent is used, the molecular weightof the parent substance can be readily calculated from the analytical datafor the monosubstituted product.38 The correct assignment of the disulphidebridges may be made possible from a consideration of atomic models ofinsulin.In at least two laboratories 397 40 the structure is being consideredon the basis of the 3.7-residue helix,41 but the work is a t an early stage.There is disagreement between the two groups as to whether or not a two-chain structure is possible.I t is now known that there are appreciable differences in compositionbetween the insulins obtained from various species.This confirms the sugges-tion made by Sange~-.~~ The six amino-acids, serine, threonine, glycine,alanine, valine, and isoleucine are present in different amounts in cattle, pig,and sheep i n ~ u l i n s . ~ ~ - 4 ~ In cattle insulin a component has been found whichhas five amide groups instead of six per two chains; this may be an artefactproduced from insulin during isolation.45Reaction of Diisopropyl Fluorophosphonate with En~ymes.~~-~-SerineO-(dihydrogen phosphate) (phosphoserine) has been isolated from partialhydrolysates of (diisopropyl phosphory1)chymotrypsin in about 30% yield.47The hydroxyl group of free serine is not reactive to diisopropyl fluorophos-phonate and only one atom of phosphorus is introduced per molecule ofenzyme.46 It could be assumed that some special configuration around aserine residue imparts to its hydroxyl group a reactivity much higher thannormal, but a more likely explanation is that the phosphorus becomesattached first to some other group and is transferred to serine duringhydrolysi~.~7? 48There is indirect evidence suggesting 4 7 7 48 that the primary site of phos-phorylation of the enzyme is a histidine residue.Photo-oxidation of chymo-trypsin destroys one histidine residue (and also 3 tryptophan residues),and the product is no longer reactive to diisopropyl fluoropho~phonate.~~The hydrolysis of the latter is accelerated in the presence of glyoxaline,histidine, pyridine, and certain of their derivatives and the suggestion is3G F.Sanger, Nature, 1953, 171, 1025.37 E. J. Harfenist and L. C. Craig, J . r3mer. Chem. Soc., 1952, 74, 3083, 3087.38 A. R. Battersby and L. C. Craig, ibid., 1951, 73, 1887; 1952, 74, 4023.39 U. W. Arndt and D. P. Riley, Nature, 1953, 172, 245.40 C. Robinson, ibid., pp. 27, 773.p2 F. Sanger, Nature, 1949, 164, 529.43 J . Lens and A. Evertzen, Biochim. Biophys. Acta, 1952, 8, 332.44 E. J . Harfenist and L. C. Craig, J . Amer. Chem. Soc., 1952, 74, 4216.4 5 E. J. Harfenist, ibid., 1953, 75, 5528.46 For a review of earlier work see A.K. Balls and E. F. Jansen, Adv. Enzymology,4 7 N. K. Schaffer, S. C. May, and W. H. Summerson, J . Biol. Chem., 1953, 202, 67.T. Wagner-Jauregg and B. E. Hackley, J . Amev. Chem. Soc., 1953, 75, 2125.4s L. Weil, S. James, and A. R. Buchert, Arch. Biochem., 1953, 46, 260.41 Ann. Reports, 1951, 48, 241.1952, 13, 321272 ORGANIC CHEMISTRY.made that this is due to formation of a quaternary complex 48 (cf. ref. 54). Ifthese views are correct such a complex must be present in the inhibitedenzyme and acts as a phosphorylating agent for the serine-hydroxyl group.48The acylating action of l-acylglyoxalines has been demonstrated re~ently.~OThe inhibition of cholinesterase by triesters of phosphoric acid appears to beclosely related to that of chymotrypsin.51These views on the mechanism of inhibition cannot be reconciled with thediscovery that diisopropyl fluorophosphonate reacts readily with the hydroxylgroup of tyrosine.The chloro-analogue, which reacts very much moreslowly, is also much less toxic; this suggests that the hydroxyl group oftyrosine may be involved in the active centre of the enzyme.52It is now known that inhibition of chymotrypsin can be reversed to asmall extent by hydroxylamine 53 and completely by nicotinohydroxamicacid methi~dide.~~ The effectiveness of the latter substance is ascribed tothe presence of an anionic site in the enzyme which survives the inhibitionprocess.Determination of Polypeptide and Protein End-groups.-N- Terminalresidues.The l3lI-labe1led P-iodobenzenesulphonyl group method 55 hasbeen applied to crystalline glyceraldehyde-3 phosphate dehydrogenase fromyeast and rabbit muscle. Both proteins contain two chains terminated byvaline residues. 56The free amino-groups of peptides can be reductively methylated withformaldehyde and the dimethylamino-acid, liberated from the terminalgroup on hydrolysis, can be identified by paper-chromatography. Thismethod gave satisfactory results on a number of peptides, including gluta-thione. No free a-amino-groups were found in bacitracin. 57The fluorodinitrobenzene (FDNB) technique has received further studyand improvement. Paper-chromatographic methods for identifying di-nitrophenyl(DNP)amino-acids are frequently used ; 58-623 31 X-ray powderdiffraction measurements provide additional confirmatory evidence.63 Acolumn procedure for acid-soluble DNP-amino-acids has been described.59The chromatographic behaviour of DNP-peptides on columns of silicic acid-Celite has been investigated in detail 64 and yields very satisfactory resultsin the separation of DNP-peptides from partial hydrolysates of gelatin.65Optimum conditions for the dinitrophenylation of amino-acids and peptideshave been worked out.66 It was not possible to cause some of the amino-6o T.Wieland and G. Schneider, Annalen, 1953, 580, 159.61 W. N. Aldridge, Biochenz. J., 1953, 54, 442.52 R. F. Ashbolt and H. N. Rydon, J . Amer. Chem. SOC., 1952, 74, 1865.53 L. W. Cunningham and H. Neurath, Biochim. Biophys.Acta, 1963, 11, 310.64 I. B. Wilson and E. K. Meislich, J . Amer. Chem. Soc., 1953, 75, 4628.5 5 A n n . Reports, 1951, 48, 239.5 6 S. F. Velick and S. Udenfriend, J . Biol. Chem., 1953, 203, 575.5 7 V. M. Ingram, ibid., 1953, 202, 193.5 8 C. Weibull, Acta Chem. Scand., 1953, 7, 335.59 E. F. Mellon, A. H. Korn, and S. R. Hoover, J . Amer. Chem. Sac., 1953, 75, 1675.6o C. H. Li and L. Ash, J . Biol. Chem., 1953, 203, 419.61 M. Rovery and C . Fabre, Bull. SOC. Chim. biol., 1953, 35, 541.62 J . H. Bowes and J. A. Moss, Biochem. J., 1953, 55, 735.63 H. M. Rice and F. J. Sowden, Canad. J . Chem., 1952, 30, 575.64 W. A. Schroeder and L. R. Honnen, J . Amer. Chem. Soc., 1953, 75, 4615.6 5 W. A. Schroeder, L. Honnen, and F. C. Green, Prac. U.S.Nut. Acad. Sci., 1953,39, 23. 6 6 W. A. Schroeder and J. Le Gette, J . Amer. Chem. SOL, 1953, 75, 4612ELLIOTT : PEPTIDES, PROTEINS, AND AMINO-ACIDS. 273acids and peptides to react quantitatively, aspartic acid being a particularlydifficult case. It is claimed 58 that quantitative estimation of protein end-groups can be achieved by the FDNB-method, with paper-chromatographyfor separation of DNP-amino-acids, followed by elution and spectrophoto-metric estimation at 360 mp.An important contribution to our knowledge of the FDNB methodhas been made in a study of the end-groups of tobacco mosaicalthough the validity of this work has been questioned.67a Dinitrophenolwas the only product isolated after hydrolysis of the DNP-virus and itwas shown that this arose almost exclusively from decomposition of DNP-proline (see also ref.68) in about 75% yield. If a molecular weight of40 x 106 is assumed for the virus, the results demonstrate that it contains2300-2700 peptide chains having N-terminal proline residues. Theseresults are in fairly good agreement with those for the C-terminal residues.69N-Terminal proline residues have been found in several protamines. 70The disturbing finding has been made 7 l that especially labile peptidebonds may be split during the preparation of DNP-proteins under the usualconditions. The sequence possibly concerned was the N-terminal asparagyl-serine in carboxypeptidase. It was found that during the reaction of theprotein with FDNB free DNP-asparagine was formed in an amountequivalent to the DNP-serine obtained on hydrolysis.In view of the factthat much less than one equivalent of DNP-serine is obtained per moleculeof enzyme, there may be an alternative explanation. It is known, forinstance, that peptide impurities are tenaciously held in crystallineproteins. 72-74Innovations in technique which have been made are : the removal ofartefacts from ether extracts of DNP-amino-acids,75 the differentiationbetween DNP-prolyl- and -hydroxyprolyl-peptides and other DNP-peptiilesby a spectrophotometric method,65 and the estimation of bis-DNP-lysine inthe presence of dinitrophenol by spectrophotometric measurement at 400 mpin 10whydrochloric acid.76 It has been reported that the destruction ofDNP-amino-acids which occurs on hydrolysis of DNP-proteins can beprevented by treating the protein first with xanthhydrol.77 Clupein can bepurified by chromatography of its DNP-derivative.78 2 : 4-Dinitrobenzene-sulphonic acid reacts with protein amino-groups at pH 10-11, to give DNP-derivatives which are water-soluble.The reaction is slower, but in the endnearly as effective as when FDNB is used.79C-Terminal residues. There is still no method available which is as6 7 G. Schramm and G. Braunitzer, 2. Naturforsch., 1953, 8b, 61.cia H. Fraenkel-Courat and B. Singer, J . Amer. Chem. SOC., 1954, 76, 180.6 8 R. Acher and U. Laurila, Bull. Soc. Chivn. biol., 1953, 35, 413.69 J. I. Harris and C. A. Knight, Nature. 1952, 170, 613.70 K. Felix and A. Krekels, 2.physiol. Chem., 1953, 295, 107.E. 0. P. Thompson, Biochim. Biophys. Acta, 1953, 10, 633.72 M. Rovery, C. Fabre, and P. Desnuelle, ibid., 1952, 9, 702.73 Idem, ibid., 1953, 10, 481.7$ P. Desnuelle, M. Rovery, and C. Fabre, ibid., 1952, 9, 109.75 Unpublished method of F. A. Isherwood and D. Cruickshank, quoted by H. M.7 6 M. Jutisz and L. Pknasse, Bull. SOC. Chinz. biol., 1952, 34, 480.7 7 S. R. Dickman and R. 0. Asplund, J . Amer. Chem. Soc., 1952, 74, 5208.78 E. Waldschmidt-Leitz and L. Pflanz, 2. physiol. Chew., 1953, 292, 150.7 9 H. N. Eisen, S. Belman, and M. E. Carsten, J . Amer. Chem. Soc., 1953, 75, 4583.Schwartz and C . H. Lea, Biochem. J . , 1952, 50, 713274 ORGANIC CHEMISTRY.effective generally for C-terminal residues as is the FDNB method for N-terminal residues.The method of reduction using mixed metallo-hydrides 55is potentially useful, but the difficulties associated with the quantitativeseparation of amino-alcohols from inorganic salts and amino-acids havenot yet been overcome. In the special case of ovornucoid, which containsterminal phenylalanine, the phenylalaninol (2-amino-3-phenylpropan-1-01)produced on reduction and hydrolysis was obtained almost quantitatively byadsorption on charcoal.80 Synthesis of the amino-alcohol from DL-cysteine 81and an improved synthesis of that from L-histidine 82 have been reported.The Schlack and Kumpf procedure 55 has received further study thisyear.s3-8G Now that a paper-chromatographic method is available 83 theidentification of the thiohydantoins is greatly simplified.Crystalline deriv-atives of serine, threonine, histidine, and arginine have not been prepared,S3and the method appears to fail with aspartic, glutamic, lysine, and arginineend-groups.@ Cleavage of the thiohydantoin by acid hydrolysis 84 is clearlypreferable to alkaline hydrolysis,85> 86 which leads to opening of the thio-hydantoin rings6 As a qualitative method it appears useful, for it has givenunequivocal results on lysozyme, 83 bovine plasma albumin,= and ovo-muc0id.8~ Alanine was found as an end-group in o v a l b ~ m i n . ~ ~ The yieldof thiohydantoin obtained by use of acetic anhydride and ammonium thio-cyanate was found to be far from quantitative,= but it is now possible toobtain high yields of thiohydantoin (VI) from simple N-acyl-peptides anddiphenyl phosphoroisothiocyanatidate (V) at room temperature.86 TheR*CO*NH*CHR*CO,- + (PhO),PO*NCS __t(V)R’CO*NH*CH RCO-NCS __t R’CO *$J- H R(VI) s(\ N H /Jooverall reaction is as shown.The phosphorus compound is readily avail-able. The suitability of this method for large polypeptides or proteins hasnot yet been ascertained.Carboxypeptidase is a valuable tool, but its limitations 87 need to bethoroughly appreciated. Of prime importance is the purity of the enzyme.ssIn favourable circumstances it yields very satisfactory result^.^*^^ Thetryptic activity which frequently accompanies the enzyme can be bbcked bytreatment with diisopropyl fluorophosphonate (DFP) .92 No C-terminalresidues were found in trypsinogen or in the DFP-complex of trypsin, orL.PBnasse, M. Jutisz, C. Fromageot, and H. Fraenkel-Conrat, Biochim. Biophys.8 1 J. C. Crawhall and D. F. Elliott, Biochem. J., 1953, 55, vii. Acta, 1952, 9, 551.88 P. Karrer and R. Saemann, Helv. Chim. Acta, 1953, 36, 570.83 J. T. Edward and S. Nielsen, Chem. and Ind., 1953, 197.84 V. H. Baptist and H. B. Bull, J . Amer. Chem. SOC., 1953, 75, 1727.8 5 R. A. Turner and G. Schmerzler, Biochim. Biophys. Acta, 1953, 11, 586.86 G. W. Kenner, H. G. Khorana, and R. J. Stedman, J., 1953, 673.J. A. Gladner and H. Neurath, J . Bid. Chem., 1953, 205, 345; cf. M. Rovery,D. Steinberg, J . Amer. Chern. SOL, 1953, 75, 4575.J. I. Harris, ibid., 1952, 74, 2944.C. Fabre, and P. Desnuelle, Biochim.Biophys. Acta, 1963, 12, 547.O0 A. R. Thompson, Nature, 1952, 169, 495.O1 F. Sanger and E. 0. P. Thompson, Biochem. J . , 1953, 53, 366.9s E. W. Davie and H. Neurath, J , Amer. Chem. SOC., 1952, 74, G305ELLIOTT PEPTIDES, PROTEINS, AND AMINO-ACIDS. 275when carbox y pep t idase was allowed to aut olyse .92 C h ymo t r ypsinogen didnot yield any amino-acids in the presence of carboxypeptidase, whereas theDFP-complex of a-chymotrypsin yielded leucine and tyrosine. I t is believedthat the formation of a-chymotrypsin from chymotrypsinogen involvesopening of a cyclic molecule with liberation of a basic ~eptide.~'At present an enzymic method is needed for the detection of a C-terminalcarboxyamide group. In the two cases so far studied, cleavage of glycineamide occurred readily in the presence of trypsin 99 lo or the plakalbumin-forming enzyme from B.~ubtiZis.~* 7Methods for Polypeptide Degradation.-Edman method. 93 Paper-chromatographic methods are now available for the identification of 3-phenyl-thiohydantoin derivatives of amino-a~ids.~~~ 95 The true thiohydantoinderivatives of serine 96 and threonine 95*96 have been prepared, but thecystine derivative is probably not a thioh~dantoin.~~ Phenyl isothiocyanatereacts incompletely with the free amino-groups of insulin in aqueous buffersolutions.97 The Edman method of stepwise degradation has been studiedmore fully than any other method; it has been used to determine theN-terminal pentapeptide sequences of ly~ozyme,~~ the result being in agree-ment with that of S ~ h r o e d e r , ~ ~ and of insulin,94~99 but in neither case was itpossible to continue the degradation.It was only partly successful in thedegradation of the hexapeptide, Ala-Gly*Val-Asp*Ala.Ala, liberated duringthe transformation of ovalbumin into plakalbumin,lm9 lol and of oxidisedvasopressin.15 These difficulties are due to the impossibility, at present, offorming the thiohydantoin ring without causing a small degree of peptide-bond fission. In the experiments described the techniques of ring closurehave varied widely; another and possibly more effective method has beensuggested recently. lo2 All these workers have applied successive steps ofthe degradation to the crude, degraded peptide from the previous stage.This is contrary to the general rule in organic syntheses.An increase in therange of the method would be expected if the degraded peptide could bepurified at every step, or every few steps of the degradation. This wouldbe a formidable task, but perhaps not an insuperable one in view of therapid advances being made in the techniques for purification of largemolecules.A modification of the Edman method in which 4-dimethylamino-3 : 5-dinitrophenyl isothiocyanate is the reagent has been briefly reported.lo3Thiohydantoin formation occurs in dilute acetic acid a t 40". The fullpublication of this work will be awaited with interest.A recent publication lo4 describes the stepwise degradation of a few simplepeptides by a method allied to the Edman technique, but as ring closure is93 Ann.Reports, 1950, 47, 165; 1952, 49, 148.94 W. A. Landmann, M. P. Drake, and J. Dillaha, J . Amer. Chem. SOC., 1953, 75, 3638.95 J. Sjoquist, Acta Chem. Scand., 1953, 7 , 447.s6 V. M. Ingram, J.. 1953, 3717.g7 E. Kaiser, L. C . Maxwell, W. A. Landmann, and R. Hubata, Arch. Biochenz., 1953,gg H. N. Christensen, Compt. rend. Trav. Lab. Carlsberg, SLY. Chim., 1953, 28, 265.loo M. Ottesen and A. WoIlenberger, Nature, 1952, 170, 801.101 Idem, Compt. rend. Trav. Lab. Carlsberg, SLY. Chim., 1953, 28, 463.lo2 I?. Edman, Acta Chem. Scand., 1953, 7 , 700.lo3 W. S. Reith and N. M. Waldron, Biochem. J., 1953, 53, xxxv.lo4 D. T. Elmore and I-'. A. Toseland, Ckenz. a i d Imd., 1953, 1227.42, 94. 98 W.A. Schroeder, J . Amer. Chem. Soc., 1952, 74, 5118276 ORGANIC CHEMISTRY.carried out under the conditions used in the Edman method it must sufferfrom the same disadvantages.If one surveys the literature in this field over the last few years it is pain-fully obvious that in spite of all the ingenuity and hard work there is not asingle stepwise method of degradation which approaches in usefulness thetechniques of partial hydrolysis used by Sanger and his collaborators (see,for instance, ref. 55). Something more specific is needed, however, to unravelprotein structures. I t is clear that experiments with simple peptides cando no more than establish the feasibility of a method; it is only afteradequate testing on naturally occurring polypeptides or proteins that its truevalue can be assessed.Effective methods have been developed for a study of the peptide linkagesin polyglutamyl-peptides. 105-107 The side-chain carboxyl groups are sub-mitted to Curtius lo5 or Hofmann degradation,loG9 lo7 and the product ishydrolysed to ay-diaminobutyric acid or p-formylpropionic acid, dependingon the nature of the linkage.The validity of the methods has been tested.... NH*YHCO * - - * . . . . NH.VH*CH,CH,CO*NH * 9 * *CH,.CH,.CO,H C0,Ht tt tNH,*qHCO,H CHOCH2CH,C0,1-ICH,CH,*NH,on a synthetic polypeptide.log Poly-D-glutamic acid from all the naturalsources so far examined appears to contain only y-glutamyl linkages. lo5-110By application of the isotopic dilution method to partial hydrolysates ithas been found that the sequence glycylalanylglycine occurs in silk fibroinmore frequently than would be the case with a random distribution of amino-acids.lll Evidence for a non-random structure in silk fibroin comes alsofrom another source.112Tri-iodothyronine.-Details of the synthesis of the L- and D-,l13 and114 forms of 3 : 5 : 3'-tri-iodothyronine have appeared. The L-form hasbeen obtained crystalline from the thyroid g1and.ll3 The mode of biologicalsynthesis is not k n 0 w n .l l ~ 3 ~ ~ ~ A high yield of monoiodotyrosine wasobtained by iodination of N-phthaloyltyrosine, but unfortunately this methodwas not successful for the preparation of tri-iodothyronine.l17lo5 J. KovAcs and V. Bruckner, J., 1952, 4255.loci V. Bruckner, J. KovAcs, and H.Nagy, J . , 1953, 148.lo7 V. Bruckner, J. KovBcs, K. KovAcs, and H. Nagy, Experientia, 1963, 9, 63.lo8 V. Bruckner, J. KovAcs, and K. KovBcs, J . , 1953, 146, 1512.log V. Bruckner, J. KovBcs, and I. Kandel, Naturwiss., 1953, 40, 243.110 V. Bruckner, J. KovAcs, and G. DCnes, Nature, 1953, 172, 508.ll1 E. Slobodian and M. Levy, J . Biol. Chent., 1953, 201, 371.112 B. Drucker, R. Hainsworth. and S. G. Smith, Shirley Inst. Mem., 1952-1963,lls J. Gross and R. Pitt-Rivers, Biochem. J , , 1953, 53, 645.11* J. Roche, S. Lissitzky, and R. Michel, Biochirrz. Biophys. A d a , 1953, 11, 215.115 Idern, ibid., p. 230. 116 J. Grossand R. Pitt-Rivers, Biochenz. J., 1953, 53, 652.117 A. Hillmann-Elies and G. Hillmann, Z. Naturforsch., 1953, 8b. 446.26, 191ELLIOTT : PEPTIDES, PROTEINS, AND AMINO-ACIDS.277Hydroxyamino-acids.-Additional examples have been found of thecis trans-oxazoline interconversion previously observed in the threonineseries; 118 these reactions appear to be stereospecific, as with the threonineisomers. cis-2-Phenyloxazoline esters (VII) are in every case convertedquantitatively into the trans-forms (VIII) under the influence of a strongbase in alcoholic solution. The R group may be methyl,l18 phenyl,llgpentadecyl,l20 or hydroxymethyl.121 The configuration of natural dihydro-sphingosine is now known to be erytlzro, as in allothreonine, on the basis ofthis interconversion and certain supporting physical evidence.120 The factthat the trans-oxazoline is much more stable than the cis-form probablyexplains why the thionyl chloride cyclisation occurs smoothly in the erythro-N-acyl derivatives of P-aryl-substituted serines 122 but not in the threo-series.123- 12* This reaction generally proceeds by an inversion mechanismafter intermediate formation of a chlorosulphinic ester and it is, presumably,necessary that rotation should occur at the bond joining the two asymmetriccarbon atoms until the distance between the chlorosulphinate group and theattacking amide group reaches a maximum. The transition complex in theerytlzro-series will then have R and C0,Et in the trans-position, the productof the reaction being a trans-oxazoline, whereas a cis-transition complexwould be formed from the threo-isomers. This inversion and cyclisation ofthe erythro-form is illustrated by the following tetrahedral models. That ofthe threo-form would have H and R in the lower tetrahedron interchanged,CL-soSynthesis of the P-phenylserines by condensation of benzaldehyde andglycine in the presence of alkali has been studied in detail; 125 both forms areobtained.Resolution of the two DL-isomers has been achieved by asym-metric hydrolysis of the trifluoroacetyl derivatives with carboxypeptidase. 126118 Ann. Reports, 1951, 48, 218.119 M. Viscontini and E. Fuchs, Helv. Chim. Acta, 1963, 36, 660.lZo H. E. Carter, J. B. Harrison, and D. Shapiro, J . Amer. Chem. SOC., 1953, 75,lz2 G. W. Moersch, M. C. Rebstock, A. C. Moore, and D. P. Hylander, zbid., 1952,la* D. 0. Holland, P.A. Jenkins, and J . H. C. Nayler, J . , 1953, 273.125 K. N. F. Shaw and S. W. Fox, J . Amer. Chem. Soc., 1953, 76, 3417, 3421.126 W. S. Fones, J . Biol. Chem., 1953, 204, 323.1007, 4703.74, 665.121 E. E. Hamel and E. P. Painter, ibid., p. 1362.123 W. A. Bolhofer, ibid., p. 5459278 ORGANIC CHEMISTRY.p-Phenylserine derivatives have been synthesised from aromatic acidchlorides and a-acylaminoacetoacetic esters. 127 In the presence of calciumhydroxide #-nitrobenzaldehyde condenses with glycine, to give threo-p-nitrophenylserine.128 The case of the condensation of P-nitrobenzaldehydewith glycine ester, about which there has been so much discussion in thepast, is clarified by the observation that the p-nitrobenzylidene derivativesof P-nitrophenylserine ethyl ester are interconvertible by prototropy undercertain conditions of condensation.124 The configuration of the productdepends on the reaction conditions,129 but it has been shown 122, 130 thatcondensation under the conditions of Dalgliesh 131 or Bermann and hisco-workers 132 gives the erythtro-form. The second diastereoisomeric form ofp-hydroxyglutamic acid has been prepared 133 and named allo-p-hydroxy-DL-glut amic acid in accordance with recent International rules, 13* although itappears to be configurationally related to threonine. Adjustment of therules may be necessary to avoid confusion in such cases.The four stereoisomers of 8-hydroxylysine have been prepared and theirconfigurations tentatively assigned.135Aspartic and Glutamic Acid.-Aspartic acid has been synthesised inalmost quantitative yield by the addition of benzylamine to the hydrolysisproduct of maleic anhydride, followed by hydrogenolysis of the benzylgroup ; asparagine was prepared by a similar route, the anhydride ring beingopened with ammonia.136 In addition to that already described a novel andsimple synthesis of L-glutamine from glutamic y-methyl ester is re~0rted.l~'Recent work l 3 * 5 139 has shown that dehydration of acetyl- and benzoyl-aspartic acid with acetic anhydride yields products with the properties ex-pected of anhydrides, although under certain conditions 1399 140 their chemicalreactivity suggests an oxazolone structure. Rearrangement to an oxazoloneprobably occurs in these instances. The profound effect of the solvent onH2y-qH.SJH Hzy----- YH-R\o/CR + CO,H OC O ~ o / c O CoRthe direction of ring opening of the anhydride with ammonia should benoted.141 The dehydration products of acylglutamic acids are also an-hydrides, which generally give a mixture of a- and y-amide on ring openingwith amines.l38, 142 Thiohydantoin formation can be used to distinguishbetween a- and y-amides.138Chromatography.-It is possible only to mention very briefly a few ofthe more significant or useful advances. Solvent systems of high resolvingla' G. Ehrhart, Chem. B e y . , 1953, 86, 713.1z9 E. D. Bergmann, H. Bendas, and C. Resnick, J., 1953, 2564.130 C. G. Alberti, B. Camerino, and A. Vercellone, Exflerientia, 1952, 8, 261 ; foot-132 E. D. Bergmann, M. Genas, and H. Bendas, Compt. rend., 1950, 231, 361.133 W. J. Leanza and K. Pfister, J . Biol. Chem., 1953, 801, 377.134 Int. Union Pure Appl. Chem., J., 1951, 3522.135 W. S. Fones, J . Anzer. Chem. Soc., 1953, 75, 4865.13* M. Frankel, Y. Liwschitz, and Y . Amiel, ibid., p. 330.137 S. Akabori and K. Narita, PYOC. Japan Acad., 1953, 29, 264.138 J. M. Swan, Nature, 1952, 169, 826.139 C. C. Barker, J., 1953, 453.S. W. Tanenbaum, J . Amer. Chem. Soc., 1953, 75, 1754.lP2 J. A. King, F. H. McMillan, and J. D. Genzer, ibid., 1952, 74, 5202.lZ8 Idem, ibid., p- 483.131 C. E. Dalgliesh, J . , 1949, 90. note 3, p. 262.140 A. Lawson, J., 1953, 1046ELLIOTT : PEPTIDES, PROTEINS, AND AMINO-ACIDS. 279power for paper-chromatography of amino-acid mixtures have been de-scribed,143* 144 as well as the separation on paper of the phenylserhes,126t hreonines,l25 nitrophenylserines, 124 and asparagine and isoasparagine. 141A new reagent for amino-acids which is especially sensitive for ornithine,sarcosine, proline, and hydr~xyproline,~~~ a sensitive test for guanidino-compounds on paper,146 and a new reagent for amino-acids, peptides, andproteins 147 after chlorination 1*8 have been described. A radiochemicalmethod of quantitative paper-chromatography with an accuracy of & 2%has been ev0lved.14~ A convenient apparatus has been made for washingof a large number of filter-paper sheets.150 Although it is not a chromato-graphic method attention should be drawn here to a beautifully designedapparatus for separation of amino-acids, peptides, and proteins by continuouselectrophoresis on paper. A multiple dipping technique has been recom-mended for the development of paper chromatograms. 152Remarkable advances have been made in the column-chromatography ofproteins. Two-phase systems have been evolved for the purification ofinsulin and other pr0teins.l5~ Separation of proteins on ion-exchange resinsseems very promising, but it may be applicable only to those of relativelyhigh stability andlow molecular weight. The resin IRC 50 has been exclusivelyused for the separation of ha3moglobin.s 154 and for the purification of ribo-n ~ c l e a s e , l ~ ~ y s o ~ y m e , l ~ ~ and chymotrypsinogen a.l57 In the last casecrude pancreatic extracts could be used.Miscellaneous.-The cyclic f o m of DL-phenylalanylglycylglycine has beenprepared by a novel method.158 Very high yields are obtained in a peptidesynthesis involving phosphorazo-compounds (IX) . These are easily preparedEtO,C*CHR*N:P*NH*CHR*CO,Et (IX) + 2CH ,Ph*O,C-NH.CH R’C0,HBCH,Ph*O,C*NH CH R’CO-I’U’HCH R’*CO,E tfrom phosphorus trichloride and amino-acid or peptide esters and reactsmoothly with benzyloxycarbonylamino-acids to give p e p t i d e ~ . l ~ ~ Opticalactivity is preserved. The value of the method is manifest from its use inthe synthesis of glutathione.lG0 A study has been made of the fission of tenprotecting groups under various conditions. Five of these are interesting143 A. L. Levy and D. Chung, Analyl. Cizem., 1953, 25, 396.14* R. R. Redfield, Biochina. Biophys. Acta, 1953, 10, 344.lg5 G. Curzon and J. Giltrow, Nature, 1953, 172, 356.146 H. Tuppy, Monatslz., 1953, 84, 342.14’ F. Reindel and W. Hoppe, Naturwiss., 1953, 40, 221.Ig8 Ann. Reports, 1952, 49, 149.14B S. Blackburn and A. Robson, Biochem. J . , 1053, 54, 295.150 F. A. Isherwood and C. S. Hanes, ibid., 1953, 55, 824.151 W. Grassmann and K. Hannig, 2. PJzysiol. Chem., 1953, 292, 32.lS2 J. B. Jepson and I. Smith, Nature, 1953, 172, 1100.153 K. R. Porter, Biochem. J . , 1953, 53, 320.154 N. K. Boardman and S. M. Partridge, Nature, 1953, 171, 208.lS5 C. H. W. Hirs, S. Moore, and W. H. Stein, J . Biol. Chem., 1953, 200, 493.ls6 H. H. Tallan and W. H. Stein, ibid., p. 507.157 C . H. W. Hirs, ibid., 1953, 205, 93.158 M. Winitz and J. S. Fruton, J . Amer. Chem. SOC., 1953, 75, 3011.159 S. Goldschmidt and H. Lautenschlager, Annalen, 1953, 580, 6 8 ; see also Ann.Reports, 1951, 48, 153. lG0 S. Goldschmidt and C. J u t z . Chem. B e y . , 1953, 86, 1116280 ORGANIC CHEMISTRY.on account of the possibility that they could be removed one after anotherfrom a molecule with which they were together combined.16l This know-ledge should be of value in the synthesis of complex peptides. Benzyloxy-carbonyl groups can be removed by the catalytic action of strong acids inanhydrous solvents. 161- 163A careful study has been made of the esterification of the free carboxylgroups of bovine serum albumin.16* A novel method has been devised forthe determination of protein thiol groups : the accuracy is &5y0 and onlysmall quantities of material are required.165Lithium aluminium hydride reduction has been used in a series of inter-conversions which establish the configurational relation between aliphaticamines and amino-acids.166 At the same time an independent proof wasobtained that L-alanine and L-valine have the same configuration.166 Theserelations had been established previously, but by less convenient and precisemethods.167 Amino-acids are conveniently converted into their methylesters by the action of methyl alcohol-thionyl chloride ; other esters may beprepared from these by alcoholysis.168 Alternative methods for amino-acidbenzyl esters are described.l637 169 It is now possible to isolate the basicamino-acids in the pure state and in good yield from protein hydrolysates bya very simple technique. 170 Cystine and lanthionine have been synthesisedin good yield by a neat method.lv1 The reader’s attention is drawn to theaccount of a Ciba Foundation Symposium on protein chemistry,172 which isrelevant to the matter in this section.D. F. E.A. S. BAILEY.I. G. M. CAMPBELL.N. CAMPBELL.J. W. CORNFORTH.P. B. DE LA MARE.D. F. ELLIOTT.T. G. HALSALL.W. G. OVEREND.J. WALKER.W. A. WATERS.B. C. L. WEEDON.161 R. A. Boissonnas and G. Preitner, Helv. Chim. A d a , 1953, 36, 875.162 N. F. Albertson and I;. C . McKay, J . Amer. Chem. Soc., 1953, 75, 5323.163 D. Ben-Ishai and A. Berger, J . Org. Chem., 1952, 17, 1564.164 H. A. Saroff, N. R. Rosenthal, E. R. Adamik, N. Hages, and H. A. Scheraga,165 T. C. Tsao and K. Bailey, Biochim. Biophys. A d a , 1953, 11, 102.166 P. Karrer and P. Dinkel, Helv. Chim. Acta, 1953, 36, 122.16’ F. Barrow and G. W. Ferguson, J., 1935, 410.1 6 * M. Brenner and W. Huber, Helv. Claim. Acta, 1953, 36, 1109.1 G 9 H. K. Miller and H. Waelsch, J . Amer. Chem. Soc., 1952, 74, 1092.170 W. Robson and A. S. M. Selim, Biochem. J., 1953, 53, 431.171 R. 0. Atkinson, F. Poppelsdorf, and G. Williams, J., 1953, 580.1 7 2 “The Chemical Structure of Proteins,” Edited by G. E. W. Wolstenholme andJ . Biol. Chem., 1953, 205, 255.M. P. Cameron, J. and A. Churchill Ltd., London, 1953

ISSN:0365-6217    

DOI:10.1039/AR9535000124

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

BIOCHEMISTRY.1. INTRODUCTION.FOUR fields of extremely active research in biological chemistry are coveredin the following Report. The hitherto unexpected “ transferring ” activityof the invertases is of both theoretical and practical interest. Carbohydratechemists are more and more making use of highly purified enzymes as toolsto aid the unravelling of amylosaccharide structures ; here the degradativeaction of enzymes follows paths which are inaccessible by present chemicalmethods.A vast amount of new knowledge regarding the chemistry of fatty acidmetabolism has recently become available. Much of it originates in almostsimultaneous reports from the laboratories of Green, Lipmann, Lynen, andOchoa, and is on the whole available, so far, only from preliminary notesand reviews.To assign priorities would be difficult and perhaps meaningless.Interest throughout the world in utilisation of resources provided by themarine algz is active. The Institute of Seaweed Research, in this country,is the focal point of much of the discovery summarised below.In many of the biological fields, chemical development is so rapid thatthe Reporters have been forced, for obvious reasons, to refer in a few instancesto presently unpublished work. It seems reasonable to expect that suchwork will be available by the time this Report reaches its readers.D. J. B.2. TRANSFRUCTOSYLATION.During the last three years paper partition chromatography, applied tothe action of hydrolytic enzymes on disaccharides, has revealed the presenceof hitherto unsuspected reaction products.Their formation can be inter-preted as the result of the transference of sugar residues from the disaccharide,acting as donor, to the various sugars present in the reaction mixture, actingas acceptors.Transg1ycosidation.-This process of enzymic transfer of sugar residueswas named “ transglycosidation ” by Rabatk, who observed transfer ofp-glucose residues from various glycosides, both artificial and natural, tosuch acceptors as ethanol, catalysed by preparations from leaves of a numberof species of p1ants.l Miwa and his collaborators have named this enzyme“ glucotransferase.” They were unable to differentiate it from @-glucos-idase, and from an examination of apricot-emulsin preparations of variousdegrees of purity, and also of p-glucosidases from various other sources,concluded that the transferring action is an inherent character of p-glucos-idase,”that the term “ transglycosyzation ” describesa view in keeping with the results reported below.Hehre has suggestedCf.J. Rabate, Compt. rend., 1937, 204, 153.E. J. Hehre, Adv. Enzymology, 1951, 11, 330.a T. Miwa, K. Takano, K. Mafune, and S. Furutani, PYOC. Japan. Acad., 1949,25, 111.a K. Takano and T. Miwa, Biochem. J . , Japan, 1950, 37, 435282 BIOCHEMISTRY.more accurately the nature of the group transferred, in those cases (phos-phorylases) where the mechanism of the reaction has been studied with theuse of 180-labelled phosphate. Koshland and Stein have investigated theaction of yeast invertase on sucrose in presence of lsO-labelled water,5 buthave so far shown only that the glucose produced does not contain l80.Despite present uncertainty, however, it seems reasonable to followHehre, and to refer to the transfer of fructose residues as “ transfructo-sylation,” and no longer as “ transfructosidation.” 6An excellent review of transglycosylation reactions, from the aspect ofpolysaccharide synthesis, has been given by Barker and Bourne.’ Themechanism of levan synthesis by various bacteria is fully discussed, and willnot be further reported here; it is evidently explicable in terms of trans-fructosylation, but the early stages in the synthesis of a molecule of thepolysaccharide have yet to be fully investigated.*and Bacon and Edel-man 10 discovered independently that the carbohydrates of the tubers andother organs of the Jerusalem artichoke appeared ona paper chromatogram as a regular series of spotsextending from the position of sucrose to the startingline, each being non-reducing and yielding both glu-cose and fructose on hydrolysis.Dedonder ll isolatedthe four lower members of this series of “ inulides ”powder, but neither he nor Bacon and Edelmanmade any structural investigations. They inferredfrom the presence of glucose and the lack of reducingsucrose, and that the series was produced by successive (f” additions of a p-fructofuranose residue to the fructoseresidue of this disaccharide. The fructose-to-fructose/O linkages were assumed to be2 : l’, asininulin.Thetrisaccharide would thus have the structure (I). ItCH,.OH still remains to be proved that this is the case,although further circumstantial evidence has sinceappeared to support it.While examining the possibility that sucrose might be the substrate forinulin synthesis, Edelman and Bacon found that tuber extracts catalysed atransfer of fructose residues from inulin to sucrose to produce a substance(or substances) having the same RF as the tuber trisaccharide, “ spot 2.”They did not demonstrate satisfactorily that the substance synthesised washomogeneous, or that it was identical with ‘ I spot 2.” Very little freeglucose was liberated from inulin-sucrose mixtures by their preparations, andquantitative paper chromatography showed that most, if not all, of thefructose appearing in the trisaccharide could be accounted for by loss ofEnzymes of the Jerusalem Artichoke.-DedonderCH,-OHOHas syrups, by partition chromatography on cellulosepower that each component was a derivative ofOHCH,*OHOH (1)D.E. Koshland and S. S. Stein, Fed. Proc., 1953, 12, 233.J. Edelman and J. S . D. Bacon, Biocham. J., 1951, 49, 529.S. A. Barker and E. J. Bourne, Quart. Reviews, 1953, 7 , 56.G. Kohanyi and R. Dedonder, Compt. rend., 1951, 233, 1142.R. Dedonder. ibid., 1950, 230, 549.lo J. S. D. Bacon and J. Edelman, Biochem. J., 1949, 45, xxvii; 1951, 48, 114.l 1 R. Dedonder, Conapt. rend., 1951, 233, 1134BACON : TRANSFRUCTOSYLATION. 283fructose from the inulin, the fructose residues of sucrose moving “ passively ”to the trisaccharide position :Appreciable amounts of free fructose were formed by all their preparations,and these were increased by raising the inulin concentration from 0-5 to2.0%; on the other hand, increasing the sucrose concentration from 1.0 to5.0% had no effect.Their preparations would also transfer fructose residuesto free fructose, or to the trisaccharides, raffinose and melezitose, but not,apparently, to glucose, maltose, lactose, or ma‘-trehalose.Dedonder 12 found an increased synthesis of higher oligosaccharides wheninulin as well as sucrose was added to tuber extracts, but considered that thesignificant amounts of free glucose liberated by his preparations indicatedthat sucrose itself was the principal donor of fructose residues in the system.He believes that the chief fructose-transferring enzyme in the tuber is an“ inulosucrase,” catalysing reactions of the type :(Fructose), + Sucrose __t (Fructose), - + TrisaccharideSucrose + Sucrose + Trisaccharide + GlucoseSucrose + Trisaccharide + Tctrasaccharide + Glucosethe oligosaccharides formed being those of the inulide series.A similarsystem in the stems differed in requiring the presence of inorganicphosphate. l2Mould Inverta~es.-Edelman~~ investigated the action of takadiast ase onsucrose, to compare it with yeast invertase, and found that it produceda series of non-reducing oligosaccharides, similar in composition and RF tothe lower inulides. Extracts of the mycelia of many species of mouldhave this action, and the same mixture of oligosaccharides appears in theculture medium when moulds are growing on sucrose as a source ofcarbohydrate.l4By “ gradient elution ” l5 with aqueous ethanol from charcoal-Celitecolumns the trisaccharide component of the oligosaccharide mixture formedby takadiastase acting on sucrose was found to consist of two substances;one was isolated as a syrup.l6 Methylation followed by hydrolysis led to theidentification of 2 : 3 : 4 : 6-tetra-@methyl-~-glucose, 1 : 3 : 4 : 6-tetra-O-methyl-D-fructose, and 3 : 4 : 6-tri-O-methyl-~-fructo9e in equal proportions.The products of partial hydrolysis were sucrose, fructose, and glucose. Sincethe trisaccharide is completely hydrolysed by yeast invertase (considered tohydrolyse only p-fructofuranosides), it probably has the structure (I).Thesame trisaccharide has been isolated and obtained crystalline by Barker andCarrington from the action of extracts of Aspergillus niger on sucrose.17They also isolated from this source another non-reducing trisaccharide withthe same general composition, i e . , 2 fructose : 1 glucose.Studies by Bealing have supported the view that the enzyme responsiblefor oligosaccharide formation is that hitherto called “ mould invertase.” l8However, Pazur has given the name “ transfructosidase ” to an oligo-l2 R. Dedonder, Bull. SOC. Chim. biol., 1952, 34, 171.l3 J. Edelman, Thesis, Univ. Sheffield, 1950.l4 F. J. Bealing and J. S. D. Bacon, Biochem. J., 1953, 53, 277.l 5 R.S. Alrn, R. J. P. Williams, and A. Tiselius, Acta Chem. Scand., 1952, 6, 826.l o J. S. D. Bacon and D. J. Bell, J., 1953, 2528.l7 S. A. Barker and T. R. Carrington, J . , 1953, 3588.l8 F. J. Bealing. Biochem. J . , 1953, 55, 93284 BIOCHEMISTRY.saccharide-forming enzyme preparation from AspergiZZus oryzae, which heapparently regards as distinct from invertase. l9 He isolated a trisaccharidefrom the reaction products, assigning to it the structure (I), on the basis ofpaper chromatography of the partial hydrolysis products. It seems prob-able that he was in fact dealing with the same enzyme, although his tri-saccharide had a specific rotation considerably lower than that recordedlater by other workers.The inhibition of mould invertase by glucose, regarded by Kuhn20 asan indication that it was an a-glucosidase, has been shown by Edelman andBealing to be due to the acceptance of fructose residues by glucose.21 Radio-active glucose added to the reaction mixture becomes incorporated rapidlyinto sucrose, and then into the other oligosaccharides.The formation of oligosaccharides by mould invertase preparations hasbeen noted by others.22,23 No evidence for a separation of the transferringactivity from the hydrolytic has been found,14 but the possibility of achievingthis has not been tested exhaustively,Pazur found that a reducing difructose was formed by the enzyme frommixtures of raffinose and fructose.19 Bealing has confirmed this, and hasalso shown that the enzyme will transfer fructose to various primaryalcohols.lsYeast 1nvertase.-The discovery that oligosaccharides are formed by yeastinvertase preparations was made independently by Blanchard and A l b ~ n , ~ ~and by Bacon and E d e l m a ~ ~ , ~ ~ in 1950; their observations have since beenconfirmed in several laboratories.26-28 A claim that a certain commercialenzyme preparation did not form oligosaccharides 29 has been shown to bedue to the low concentration of sucrose employed for the test.30 The ratioof transference to hydrolytic action by yeast invertase preparations is muchsmaller than that for mould preparations ; oligosaccharide formation isfavoured by high sucrose concentrations in bothA paper chromatogram of the products at an intermediate stage of thereaction showed, in addition to sucrose, glucose, and fructose, several otherspots numbered I to V.25127 Of these components, IV is a tetrasaccharidein nature, while the others occupy the positions of trisaccharides (11, 111)and disaccharides (I, V) .Blanchard and Albon first showed that a trisaccharide fraction from thereaction mixture had the approximate composition 2 fructose : 1 glucose.White and Secor showed that components I1 and I11 separately had thiscomposition, and also that component I was a reducing disaccharide formedfrom glucose and fructose.27 Kestose, a trisaccharide with the R F of com-31lo J.H. Pazur, J . BioE. Chem., 1952, 199, 217.2o R. Kuhn, 2. physiol. Chem., 1923, 129, 57.2 1 J. Edelman and F.J. Bealing, Biochem. J., 1953, 53, ii.22 K. Wallenfels and E. Bernt, Angew. Chem., 1952, 64, 28.28 H. Kurasawa, S. Saito, N. Honma, and Y. Yamamoto, Bull. Fuc. Agric., Nigata24 P. H. Blanchard and N. Albon, Arch. Biochenz., 1950, 29, 220.25 J. S. D. Bacon and J. Edelman, ibid., 1950, 28, 467.26 E. H. Fischer, L. Kohths, and J. Fellig, Helv. Chim. Actu, 1951, 34, 1132.28 J. W. White, ibid., 1952, 39, 238.30 S. Aronoff and J. S. D. Bacon, zbid., 1952, 41. 476.31 J. S. D. Bacon, Biochem. J., 1954, in the press.Univ., Nigata, Japan, 1953, 4, 51.L. M. White and G. Secor, Arch. Biochem., 1952, 36, 490.a0 S. Aronoff, ibid., 1951, 34, 484BACON : TRANSFRUCTOSYLATION. 285ponent 111, isolated by partition chromatography on cellulose powder, wasshown to have the structure (11) by methylation, hydrolysis, and analysis ofthe products.32Component I was isolated by the same method.Its hypoiodite oxidationproduct no longer yielded glucose on hydrolysis; the fructose content wasvirtually unchanged.31 Whelan and Jones isolated a similar substance fromthe products of action of yeast invertase on a mixture of methyl p-fructo-furanoside and glucose.33 After reduction with sodium borohydride it washydrolysed by yeast invertase to a mixture of fructose and sorbitol (D-glucitol); treatment with sodium metaperiodate gave almost the 4 mols. offormic acid expected from O-6-[ p-D-fructofuranosyl]-D-gl~cose.~The use of gradient elution from charcoal-Celite has shown that com-ponent I1 consists of two substances, named 11, and 11, in order of theirelution.31 The former was indistinguishable from the trisaccharide (I) pro-duced by mould invertase; it required the same concentration of ethanolfor elution, and had the same RF, the same mobility on filter-paper electro-phoresis in borate buff er,34 and the same infra-red absorption spectrum.Component 11, has been shown by methylation studies to have the structure(11q.35OHCH,*OHHOCH, 0 I/\\Gradient elution also provided a means of separating component V fromsucrose.31 The pure material had seven-tenths of the reducing power of itshydrolysis products, which consisted only of fructose. Filter-paper electro-phoresis showed two major components and a minor one.34Radioactive glucose added to the reaction mixture was incorporatedonly into component I, radioactive fructose into component V.36The fructose residue of methyl p-fructoside was transferred to glucose,mannose, galactose, sorbitol, and mannitol, but not to sugars without aprimary alcoholic group (arabinose, ribose, r h a m n ~ s e ) .~ ~32 N. Albon, D. J. Bell, P. H. Blanchard, D. Gross, and J. T. Rundell, J., 1953, 24.33 W. J . Whelan and D. M. Jones, Biochem. J., 1953, 54, xxxiv.34 D. Gross, Nature, 1954, 173, 487.35 D. Gross, P. H. Blanchard, and D. J. Bell, J . , 1954, in the press.36 J. Edelman, Biochem. J., 1954, 57, 22286 BIOCHEMISTRY.Addition of various primary alcohols to a mixture of enzyme and sucrosegave rise t o additional fructose-containing substances; 379 38 that formed inthe presence of methanol is apparently methyl p-fr~ctofuranoside.~~ Theglycerol added to stabilise commercial invertase preparations gives rise tosubstance first noticed by Bacon and Edelman on phenol-water paperchrornatogram~,~~ and later by Gross during paper-electrophoresis examin-ation of the reaction mixture; 34 it is presumed to be a monofructosyl-glycerol.Some of the above-mentioned oligosaccharides have been noticed duringthe growth of yeasts on sucrose-containing media.39 Their possible import-ance in the sugar industry has been discussed.40The Significance of Transfructosy1ation.-In the Jerusalem artichoketransfructosylation has been suggested as the means by which the carbo-hydrate composition changes during the winter months, leading to anincrease in the proportion of the lower terms of the inulide series.41 Altern-atively, transfructosylation from some fructosyl derivative as yet un-discovered, or Dedonder’s inulosucrase acting upon sucrose, may be themeans by which the Compositae synthesise inulin and inulides.In the case of the invertases it remains to be proved conclusively that thetransfructosylase and hydrolase activity belong to the same enzyme mole-cule, although the presence of transferring activity in highly purified yeastinvertase makes this appear more likely.26 Fischer and his colleagues,*6followed by others, have suggested a scheme of enzyme action :Sucrose + Enzyme --e Glucose + Fructosyl-enzymeFructosyl-enzyme + Water __t Fructose + EnzymeFructosyl-enzyme + Sucrose + Trisaccharide + EnzymeThe last reaction may be generalised :Fructosyl-enzyme + H0.R + Fructosyl-0.R + EnzymeAccording to this scheme, transfructosylation is to be regarded as anindication of the mechanism of fructosidase action ; no fundamental distinc-tion is made between the transfer of a fructose residue and the hydrolysisof a fructoside.The first step in either reaction is the formation of afructosyl-enzyme compound, which may then react with any one of a numberof substances carrying a hydroxyl group.A number of other carb~hydrases,~~ and other kinds of hydrolases(phosphatases, peptidases), have been found to cataIyse group-transferreactions, and Morton, reviewing these,43 has suggested that all hydrolyticenzymes capable of attacking more than one substrate may be found t o actas transferring enzymes.(Edelman and Bacon discussed the possibilitythat their “ transfructosidase ” was identical with the hydrolytic fructos-idase of the artichoke 44)s7 J. S. D. Bacon, Biochem. J., 1952, 50, xviii.88 A. I. Oparin and M. S. Bardinskaya, Doklady Akad. Nauk S.S.S.R., 1953, 89, 531.ss E. C. Barton-Wright and G. Harris, Nature, 1951, 167, 560.4o H. C . S. de Whalley, Int. Sugar J., 1952, 54, 127; B. Freed and D. Hibbert, 1953,41 J. S. D. Bacon and R. Loxley, Biochem. J., 1952, 51, 208.42 K. Wallenfels, in “Biologie und Wirkung der Fermente,” 4th Colloquium der4s R. K. Morton, Nature, 1953, 172, 65.44 J. Edelman and J. S. D. Bacon, Biorhent. J., 1951, 49, 446.Paper to Sixth Technical Conference, British Sugar Corp., Ltd.Gesellschaft fur Physiologische Chemie, Springer, Berlin, 1950, p‘.160BACON : TRANSFRUCTOSYLATION. 287Most results so far reported are consistent with Fischer’s scheme, butthere is no direct evidence that a fructosyl-enzyme compound is formed.This intermediate should arise whatever substrate is being acted upon, andthe transfer reactions which follow its formation should depend only uponthe nature and concentrations of the acceptors present. In the case of yeastinvertase a fructosylglucose is formed in the presence of glucose, whethersucrose or methyl p-fructoside is the substrate, but it remains to be provedthat the same fructosylglucose is formed in each case.Edelman hasapplied this test to mould invertase; 36 here the product of fructosetransfer from sucrose to glucose is sucrose, but he could detect no sucroseformation when the mould enzyme acted on a mixture of methyl p-fructosideand glucose. If it could be proved more conclusively that sucrose does notappear during the latter reaction the fructosyl-enzyme hypothesis in itssimple form would have to be abandoned.In every fructose-transferring system discovered, including levan-sucrase, free fructose is produced.45 Among the enzymes attacking glucosidiclinkages there is one, sucrose phosphorylase, that evidently forms anintermediate glucosyl-enzyme compound ; this enzyme, however, shows nohydrolytic activity.46 Dextransucrase, the analogue of levansucrase, mayalso produce no free glu~ose.~ I t will be interesting to see whether anytransfructosylases exist that do not have some hydrolytic action.Progress in the isolation and characterisation of the products of trans-fructosylation to sugars has up till now shown the transference to berestricted to primary alcoholic groups.However, the isolation from mouldenzyme action of a trisaccharide with the same RF and the same hexosecomposition as kestose, but with a different specific r~tation,~’ suggeststhat some transfer to secondary alcoholic groups occurs. The apparentlymultiple nature of component I11 of the yeast invertase-sucrose reactionmixture suggests that the same may be true of the yeast enzyme, as also doesthe existence of various unidentified minor components of this mixture.31The evidence already available shows qualitative differences between theartichoke, mould, and yeast enzymes, with respect to the products of transfer.The differences do not necessarily mean that the acceptor molecule has to beactivated before it can take part in the reaction, but must mean that thespecific action of the enzyme extends to groupings other than the p-fructo-furanosyl radical itself, a concept already well established for some carbo-h y drases.The recognition of transfructosylase activity where it was not hithertosuspected must lead to a fresh consideration of the relation between plantinvertases and sucrose synthesis.It is also relevant to the discovery offructose-containing oligosaccharides in the leaves and stems of barley 49and in wheatJ.S. D. B.45 S. Hestrin and S. Avineri-Shapiro, Biochem. J., 1944, 38, 2.46 W. 2. Hassid and M. Doudoroff, Adv. Carbohydrate Chem., 1950, 5. 46.4 7 E. J. Bourne, S. A. Barker, and T. R. Carrington, personal communication.4 * S. Veibel, in J. B. Sumner and K. Myrback, “The Enzymes,” Vol. I, Part I,49 H. K. Porter and J. Edelmsn, Biochem. J., 1952, 50, xxxiii.60 L. M. White and G. Secor, Arch. Biochem., 1953, 43, 60.Academic Press, New York, 1950, p. 583288 BIOCHEMISTRY.3. THE ENZYMIC DEGRADATION OF STARCH AND GLYCOGEN.This section of the Report is confined to recent developments in thechemistry of the enzymic degradation of starch and glycogen ; the literatureto the end of 1950 has been adequately reviewed el~ewhere.l-~ During thepast few years, important advances have been made, particularly in studiesof the enzymes hydrolysing the inter-chain linkages in branched amylo-saccharides.Progress has been facilitated by the development of improvedprocedures for the preparation of highly purified substrates,6> 7 by improvedmethods of protein chemistry resulting in the crystallisation of severalenzymes, and applications of chromatographic analysis to the products ofenzyme action.8-10 However, detailed knowledge of the fine structures ofstarch and glycogen is still incomplete, and until more progress has beenmade by purely chemical methods the exact specificity and mode of actionof certain amylases cannot be fully understood.Reports of the presence of“ anomalous ” linkages in amylose,ll amylopectin,12 and glycogen,l29 13and the occurrence of fructose in certain samples of glycogen l4 and waxymaize starch 8 require further chemical investigation. In this connection,the new procedure devised by F. Smith and his co-workers l2 for the deter-mination of the fine structure of polysaccharides should be noted.The biological synthesis of starch and glycogen has been reviewed indetail,l5 and, apart from a consideration of the reversible action of thephosphorylases, will not be considered further here.The General Structure of Starch and Glycogen.-Before discussing theresults of enzymic degradations of starch and glycogen, a brief account oftheir structures will be given.Attention is drawn to recent reviews.l6, l7Starch contains two distinct components-an essentially linear polymer(amylose) and a branched polymer (amylopectin), both consisting of D-glUC0-pyranose units. Evidence available from chemical and enzymic studies l81 K. Myrback and G. Neumiiller in “ The Enzymes,” by J. B. Sumner and K. Myr-2 M. L. Caldwell and M. Adams, A d v . Carbohydrate Chem., 1950, 5, 229.4 R. W. Kerr and H. Gehman, Die Starke, 1951, 3, 271.6 P. N. Hobson, S. J. Pirt, W. J. Whelan, and S. Peat, J., 1951, 801.back, Academic Press, New York, 1951, Vol. I, p. 653.P. Bernfeld, Adv. Enzymology, 1951, 12, 379.K. H. Meyer, Angew. Chewz., 1951, 63, 153.R. S. Higginbotham and G. A. Morrison, Shirley Inst. Mem., 1948, 22, 148; K.H.Meyer and P. Rathgeb, Helv. Chim. Actu, 1948, 31, 1533 ; E. H. Fischer and W. Settele,ibid., 1953, 36, 811.W. J. Whelan and P. J. P. Roberts, Nature, 1952, 170, 748.Idem, J., 1953, 1298.lo J. H. Pazur, D. French, and D. W. Knapp, Iowa State Coll. J . Sci., 1950, 57, 203.l 1 S. Peat, S. J. Pirt, and W. J. Whelan, J., 1952, 705, 714; S. Peat, G. J. Thomas,and W. J. Whelan, ibid., p. 722.12 M. Abdel-Akher, J. K. Hamilton, R. Montgomery, and F. Smith, J . Amer. Chem.Soc., 1952, 74, 4970.l4 S. Peat, P. J. P. Roberts, and W. J. Whelan. Biochem. J., 1952, 51, xvii.l6 S. A. Barker and E. J. Bourne, Quart. Reviews, 1953, 7, 5 6 ; E. J. Bourne, Bio-chem. SOC. Symp., !?53, 11, 3.l6 R. W. Kerr, Chemistry and Industry of Starch,” Academic Press, New York,1950, 2nd edn.; E.J. Bourne, Chem. and Ind., 1951, 1047,; K. H. Meyer and G. C .Gibbons, Adv. Eyzymology, 1951, 12, 341 ; W. 2. Hassid in Organic Chemistry,” Vol.IV, Ed. by H. Gilman, Wiley, New York, 1953, p. 901.l7 K. H. Meyer, Experientia, 1952, 8, 405.R. H. Hopkins, Nature, 1953, 171, 429; B. Lindberg, Aclu Chem. Scund., 1953,7, 237.l3 D. J. Bell, J.. 1948, 992MANNERS : ENZYMIC DEGRADATION OF STARCH AND GLYCOGEN. 289does not support the suggestion by J. Blom and B. Schwarz l9 that starchcontains glucofuranosidic linkages. Most starches contain ca. 20% ofamylose ; l6 the amylose content of waxy cereal starches, however, is less than2%,16 whilst that of wrinkled pea starches is 65-80%.20Amylose molecules usually consist of a linear chain of several hundreda-1 : 4-linked glucose residues, the number depending on the 22and may vary with the method of extraction from the starch granule.23There is evidence that some samples of amylose contain P-glucosidic Iink-ages,ll and that others may have a low degree of branching 22, 24-26 (seep.293).Amylopectin is composed of several hundred unit-chains, each consistingof 20-25 a-1 : 4-linked glucose residues ; * each chain is linked to an adjacentchain by a 1 : 6-glucosidic linkage. Amylopectins from different sourcesvary in chain 27 in molecular weight,24 and in the position of branch-ing in the unit-chains (see Table 2). Certain amylopectins appear to beheterogeneous, and can be separated into fractions of different degrees ofbranching and molecular weight .28 Other amylopectins, however, show novariation in degree of branching on fracti~nation.~~ A few higher plants(e.g., Zea mais) contain branched amylosaccharides with 12-unit chains ; 30, 31these polysaccharides should be described as amylopectins, and not asglycogens, as hitherto.30Although several molecular structures have been proposed for amylo-pectin,16 only two will be considered here, namely, the singly-branched(laminated) structure proposed by W.N. Haworth and E. L. Hirst 32 as thesimplest structure in accord with data from methylation studies, and themultiply-branched (tree) structure suggested by K. H. M e ~ e r . ~ ~ Both areillustrated in the Figure. Various types of “ unit-chain ” can be distin-g ~ i s h e d , ~ ~ viz.: A-type (side chain)-joined to the rest of the molecule onlyby a Iinkage from the reducing group; B-type (main chain) to which areattached other chains; and C-type terminated by the sole reducing groupof the molecule. Furthermore, A-chains and those parts of B- and C-chainsbetween the branch point and the non-reducing terminal group will bereferred to as “ exterior ” chains; those parts between two branch pointswill be regarded as “ interior ” chains (see Figure).l9 J . Blom and B. Schwarz, Nature, 1952, 6, 697.2o A. I,. Potter, V. Silveira, R. M. McCready, and H. S. Owens, J . Amer. Chem. SOC.,21 A. L. Potter and W. 2. Hassid, J . Amer. Chem. SOC., 1948, 70, 3488.22 Idem, ibid., 1951, 73, 593.23 R. T. Bottle, G.A. Gilbert, C. T. Greenwood, and K. N. Saad, Chem. and Ind.24 A. L. Potter and W. 2. Hassid, J . Amer. Chem. Soc., 1948, 70, 3774.z 5 R. W. Kerr and F. C. Cleveland, ibid., 1952, 74, 4036.2 6 B. N. Stepanenko and E. M. Afanas’eva, Chem. A h . , 1953, 47, 2282.27 D. J. Bell, Ann. Reports, 1947, 44, 223.28 K. H. Meyer and W. Settele, Helv. Chim. Acta, 1953, 36, 197.29 A. L. Potter and W. 2. Hassid, J . Amer. Chem. SOC., 1951, 73, 997.30 W. Dvonch and R. L. Whistler, J . Bid. Chem., 1949, 181, 889.31 K. H. Meyer and M. Fuld, Helv. Chim. Acta, 1949, 32, 757.32 W. N. Haworth, E. L. Hirst, and F. A. Isherwood, J . , 1937, 577.33 K. H. Meyer and P. Bernfeld, Helv. Chim. Acta, 1940, 23, 875.34 S. Peat, W. J. Whelan, and G. J . Thomas, J., 1962, 4546.* All figures quoted for unit-chain lengths, which are given to the nearest whole1953, 75, 1335 ; D.M. W. Anderson and C. T. Greenwood, personal communication.1953, 541.number, represent mean values.REP.-VOL. L 290 BIOCHEMISTRY.Glycogen, the reserve carbohydrate of animals, and certain yeasts,35, 36bacteria,37 and protozoa,38 has a highly branched structure comprisingseveral hundred unit-chains of ca. twelve a-1 : 4-linked glucose residues;the inter-chain link is of the 1 : 6-glucosidic type.l63 39 The molecular weightAA'Ti=Qj*;i-*2; -- . *-r-* '$#:Singly- and multiply-branched structures f o r amylopectin.Linear chain of a-1 : 4-linked glucose units.3. 1 : 6-Inter-chain linkage.R Free reducing group. /--. Extent of p-amylolysis.A, B, C Types of unit-chain.of glycogens ( 106-107) varies with the source.4o Whilst most glycogenshave a chain length of 12 & 2 glucose units,39, 41-43 samples have been isolatedwith chain lengths of ca.6 399 41 or 15-23.419 4 4 9 45 In many instances thesespecimens have been assayed by more than one method. The existence ofdifferent average chain-lengths presumably reflects differences in equilibriabetween the enzymes : phosphorylase, branching enzyme, amylo-1 : 6-glucosidase and glu~ose-6-phosphatase.~~ Glycogen appears to have a " tree ''structure similar to that proposed by Meyer for amylopectin, but withshorter unit-chains.l6> 47Degradation of a-1 : 4-Linkages by Hydrolytic Enzymes (Amylases) .-A . Amylases firoducing maltose (@-amylases).p-Amylases catalyse the step-wise hydrolysis of chains of 1 : 4-linked a-glucose units by attacking alternatelinkages, with the liberation of @-maltose. This action, involving a Waldeninversion, commences a t the non-reducing end of the chain and is arrestedby the presence of glucosidic linkages other than cc-1 : 4. p-Amylolysis is35 D. H. Northcote, Biochem. J., 1953, 53, 348.36 D. J. Manners and K. Maung, unpublished work.37 C. Barry, R. Gavard, G. Milhaud, and J- P. Aubert, Ann. Inst. Pasteur, 1953, 84,39 D. J. Manners, Biochem. J . , 1953, 55, xx.40 C. T. Greenwood, Adv. Carbohydrate Chem., 1952, 7 , 300; B. S. Harrap and D. J.I1 D. J. Bell and D. J . Manners, J . , 1952, 3641; unpublished work.M. Abdel-Akher and F.Smith, J . Amer. Chenz. Soc., 1951, 73, 994.43 M. Morrison, A. C. Kuyper, and J. M. Orten, ibid., 1953, 75, 1502.44 B. Illingworth, J. Larner, and G. T. Cori, J . B i d Chem., 1952, 199, 631.45 M. Schlamowitz, ibid., 1951, 188, 145.46 G. T. Cori and C . F. Cori, ibid., 1952, 199, 661.4 7 J. Larner, B. Illingworth, G. T. Cori, and C. F. Cori, ibid., p. 641.606. 38 D. J. Manners and J. F. Ryley, Biochem. J . , 1952, 52, 480.Manners, Nature, 1952, 170, 419MANNERS : ENZYMIC DEGRADATION OF STARCH AND GLYCOGEN. 291therefore confined to the exterior chains of amylopectin and glycogen.l% 3-5@-Amylase has no action on the intact starch gran~1e.l~p-Amylases occur only in higher plants; soya-bean @-amylase has beenhighly purified,ll whilst those from barley,48 sweet potato,49 and wheat 50have been crystallised.Crystalline sweet-potato p-amylase has been sub-jected to a full physicochemical analysis by s. Englard and T. P. Singer 51who, with S. Sorof,S2 have shown that free -SH groups are essential forenzymic activity-a conclusion reached independently by N. I. Proskurya-k ~ v . ~ ~ P-Amylases are inhibited by a variety of reagents, includingheparin,54 sodium dodecyl ~ u l p h a t e , ~ ~ sodium cyanide, 56 and ascorbic acid. 57Although the crystallisation of an enzyme is indicative of a high degree ofpurity, it is not a criterion of enzymic homogeneity. Certain crystallinep-amylases contain minute traces of a-amylase 58 and/or Z-enzyme and, unlessthe enzyme concentration and pH of the digestion are controlled, these con-taminating enzymes interfere with true p-amylolysis.The limit of p-amylolysis of amylose (see Table 1) is dependent on(a) the sample of amylose and (b) the enzyme concentration, Some amyloses,TABLE 1.The degradation of amyloses by crystalline sweet potato p-amylase.Source of amyloseApple ..................Maize ...............Maize ...............Maize ...............Potato ...............Potato ..................Potato ..................Sago ..................Sago ..................Tapioca ...............D.P.* of amylose /3-Amylolysis limit t Ref.545 90 59- 75 60- 68 11490 90 61- 88 GO- 68 11- 75 411200 70 11, 621200 97 633500 70 11, 62* Degree of polymerisation. t Percentage conversion into maltose.especially those of low molecular weight, are completely hydrolysed byp-amylase, and are presumed to be linear a-1 : 4-g1u~osans.l~ Other samples,however, are incompletely degraded, particularly a t low enzyme concen-trations.Sago amylose, for example, has 8-amylolysis limits of 70 l1 and970/, 63 with low and high concentrations of enzyme respectively. Thisapparent discrepancy is due to the presence of anomalous linkages in theamylose,ll and to traces of Z-enzyme in the crystalline p-amylase. Theactivity of Z-enzyme, which hydrolyses these anomalous linkages, is insig-4 8 K. H. Meyer, E. H. Fischer, and A. Piguet, Helv. Chim. A d a , 1951, 34, 316.49 A. K. Balls, M. K. Walden, and R. R. Thompson, J . Biol. Chem., 1948, 173, 9.50 K.H. Meyer, P. F. Spahr, and E. H. Fischer, Helv. Chim. Acta, 1953, 36, 1924.51 S. Englard and T. P. Singer, J . Biol. Chem., 1950, 187, 213.52 S. Englard, S. Sorof, and T. P. Singer, ibzd., 1951, 189, 217.53 N. I. ProskuryHkov, V. Y . Voronkova, and E. S. Mikhailova, Cheun. Abs., 1952,5 5 Idem, ibid., 1952, 4, 531.56 D. K. Roy and L. A. Underkofler, Cereal Chem., 1950, 27, 404.j 7 N. I. Proskuryakov and L. S. Kholopova, Chem. Abs., 1953, 47, 3903.5 8 R. H. Hopkins and R. Bird, Nature, 1953, 172, 492.5Q A. L. Potter, W. 2. Hassid, and M. A. Joslyn, J . Amw. Chem. SOC., 1949, 71,61 S. Nussenbaum and W. 2. Hassid, J . Biol. Chem., 1951, 190, 673.62 W. J . Whelan, personal communication.63 T. G. Halsall, Thesis, Manchester, 1948.46, 10316.54 K. Myrback and B. Persson, Arkiv Kemi, 1953, 5, 477.4075. 80 A. L. Potter, personal communication292 BIOCHEMISTRY.nificant at low concentrations of crystalline p-amylase ; at higher concentra-tions, however, the amount of Z-enzyme is sufficient to affect the p-amylolysislimit.These lower p-amylolysis limits are due neither to impurities in theamylose-as suggested by Meyer 17-n0r to retrogradation of the substrate,since on the addition of Z-enzyme (a p-glucosidase), or emulsin, completep-amylolysis occurs.11 It is assumed that such amyloses contain one ormore p-glucosidic linkages which arrest P-amylase action ; 11 the exactsituation of such linkages is not known and the tentative suggestion thatthey join single glucose residues to the main chain has not been confirmede~perimentally.~~ (Recent additional evidence confirms that Z-enzyme is ap-glucosidase and not a weak a-amylase ; 64 it occurs in soya beans,ll wheat,65barley,41 rye,66 and other ungerminated cereals ; its presence in amorphouspreparations of p-amylase accounts for the ability of such preparations com-pletely to hydrolyse amylose, and slowly to attack laminarin and yeastglucan.) From a study of the rate of p-amylolysis of various samples ofamylose, it has been concluded that potato and tapioca amyloses containone or two and two or three branch points respectively, per molecule.25Crystalline @-amylase will rapidly hydrolyse short-chain maltosaccharidesto maltose or to a mixture of maltose and maltotriose, according to the chainlength of the substrate; 67 whether or not maltotriose is a substrate forp-amylase has not yet been finally decided.68E.J. Bourne and W. J. Whelan have reviewed the mechanism of p-amylo-lysis of a m y l o ~ e . ~ ~ Two theories of enzymic action have been proposed.The " single-chain " theory postulates that p-amylase completely degradesone amylose molecule to maltose before attacking a second molecule; a tintermediate stages of hydrolysis, only maltose and unchanged amylose arethus present. According to the " multi-chain " theory, enzyme actioninvolves a simultaneous attack of all the amylose molecules, each of whichis therefore progressively shortened. Recent work has shown that enzymeaction is normally intermediate between these two mechanisms, but that athigher temperatures it approximates to a multi-chain action.68$ '* p-Amylaseis a remarkably efficient catalyst; the turn-over number in terms of gluco-sidic linkages ruptured per minute at 30" and pH 4.8 is ca.250,000 52 (not2,370,000 as reported previously 51).The products of p-amylolysis of branched amylosaccharides are maltoseand a limit-dextrin of high molecular weight (p-dextrin).l, 3-5 This dextrindiffers from the original polysaccharide only in that the exterior chainscomprise two or three glucose residues 34, 44 (not one or two as originallysuggested by Meyer 5). The original exterior chain lengths of amylopectinscan therefore be calculated from the p-amylolysis limit and chain length,as shown in Table 2.Amylopectins do not contain Z-labile 1inkages.ll64 S. Peat and W. J. Whelan, Nature, 1953, 172, 494.6 5 T. Dillon and P. O'Colla, Chem. and Ind., 1951, 111.6 6 A. M. Liddle and D. J. Manners, unpublished work.6 7 W. J. Whelan, J. M. Bailey, and P. J. P. Roberts, J., 1953, 1293; cf. also R. H.Hopkins and B. Jelinek, Biochem. J., 1954, 58, 136; R. Bird and R. H. Hopkins, ibid.,p. 140; R. W. Kerr and F. C. Cleveland, J . Amev. Chem. SOC., 1951, 73, 2421.68 W. J . Whelan, Biochem. SOC. Symp., 1953, 11, 17.69 E. J. Bourne and W. J. Whelan, Nature, 1950, 166, 258.70 D. French, D. W. Knapp, and J. H. Pazur, J. Amev. Chem. Soc., 1950, 73, 1866MANNERS : ENZYMIC DEGRADATION OF STARCH AND GLYCOGEN. 293TABLE 2. T h e degradation of amylopecfins by crystalline p-amylase.Wheat ........................18, e 11 13-14 3-4 47Waxy maize ............... 19, p 13 15-16 2-3 28Synthetic .................. 20-21, e, p 10-11 13 7 61Waxy maize ............... 22 m, p 11-12 14 7 71Tapioca ..................... 22, 15 17-18 3-4 28Waxy maize ............... 23, p 16 18-19 3-4 28Apple ........................ 24, p 15 17-18 5-6 59Maize ..................... 24, e 16-16 18 5 47Source Chain length A B C Ref.Waxy sorghum ............ 25, m, p 13 15-1 6 8-9 71e = Enzymic assay.fi = Periodate oxidation assay.m = Methylation assay.A = No. of glucose units removed on /?-amylolysis.B = Exterior chain length (A + 2.5).C = Interior chain length (chain length - B - 1 ) .The discovery of Z-enzyme has provided an explanation for the variationin the p-amylolysis limit of whole starches.Crystalline or acid-treatedp-amylases, which are free from Z-enzyme, yield ca. 53% of maltose, butother preparations, which contain Z-enzyme, yield ca. 60%, the differencebeing due to the extent of hydrolysis of the amylose component.A critical study of the p-amylolysis of glycogen has been made recently 41and typical results are recorded in Table 3. Animal 41 and yeast 35 glycogensdo not contain Z-labile linkages.TABLE 3.Source Chain length A B C Ref.............. 2 4-5 1-2 41..................... 6 8-9 2-3 35Helix poinatia 7, PYeast 12, p, mTetrahymena pyrifovniis . 13, p 6 8-9 3-4 38Rabbit liver ............... 13, p , +n 5-6 s 4 41Cat liver ..................13, p 6-7 9 3 41Rabbit liver ............ 15, e 7 9-10 4- .? 47Mytilus edulis ............. 17, p , m 8 10-1 1 5-6 41Rabbit liver ............... 18, m 9-10 12 5 71T h e degradation of glycogens by crystalline sweet-potato p-amylase.* See Table 2 for footnotes.From Tables 2 and 3 it can be seen that glycogens and amylopectins showconsiderable variation in molecular structure ; differences in degree andposition of branching can be noted between (a) samples from differentsources, and (b) different samples from the same source, whilst amylo-saccharides with the same chain length vary in the position of branching inthe chain.a-Amylasescatalyse random hydrolysis of a-1 : 4-linkages in both starch and g1ycogen.l-5They also attack the intact starch granule l7 (cf. p-amylases).The purifiedenzymes cannot hydrolyse the 1 : 6-inter-chain linkages in branched amylo-saccharides, but can by-pass them so that both exterior and interior chainscan be degraded. a-Amylolysis is characterised by a rapid decrease of theiodine staining power,l t ~ r b i d i t y , ' ~ and viscosity of the substrate (adextrinisation action), followed by the slow production of reducing sugars(a saccharification action). Random hydrolysis of linkages during theinitial stages of g-amylolysis yields achroic a-dextrins (D.P. 6-10> which areB. Amylases producing more than one sugar (u-amylases).T. G. Halsall, E. L. Hirst, L. Hough, and J. K. N. Jones, J., 1949, 3200.72 S. Schwimmer, J .Biol. Chem., 1950, 188, 477294 BIOCHEMISTRY.then slowly hydrolysed to mixed saccharides, the nature of which dependson the substrate and the source of a-amylase. Different a-amylases showdifferent affinities for the same substrate. For example, salivary amylasereadily attacks starch, maltohexaose, and maltohexaonic acid, with approx-imately the same initial velocity. With malt a-amylase, however, the initialrates of degradation are in the ratio 50 : 9 : 1 respectively.73a-Amylases are widely distributed in Nature, and many have now beenpurified and crystallised, eg., those from malt,l7, 74 human saliva,17 humanpancreas,17 swine pancreas,l71 75 B. subtilis,17 B. masentericus, 76 Aspergillusovyzae,l79 7 7 3 78 and A. candidus var. amylolyti~us.~~ The chemical andphysical properties of several crystalline a-amylases have been reviewed byK.H. M e ~ e r . ~ ~ ~ ~ It has been reported that crystalline malt a-amylasecontains traces of another enzyme, a “ dextrinase.” Purified a-amylaseshave been isolated from Clostridium butyricum (from pig caecum 81 and sheeprumen 82), Cl. acetobutylicum,s3 a variant of CZ. paste~rianium,~~ and a strainof Streptococcus from sheep rumen.82The nature of the “ active group ” in a-amylases is not yet known,although there is some evidence that a free -OH group (tyrosine) is con-cerned; -SH groups are not e ~ e n t i a l . ~ , 85 The suggestion 86 that inositolis an active constituent of a-amylases has now been 87, 88Certain a-amylases (from B. subtilis, and mammalian pancreatic or salivarysecretions) require C1- for maximal activity.2* 59 l7 The effects of urea,ammonium phosphate, and temperature variation on the activation ofsalivary amylase by C1- have been studied by L.H. S ~ h n e y e r . ~ ~ Malta-amylase is activated by Ca++, 1 7 7 74, 75 whilst A . oryxae a-amylase is unaffectedby either of these ions.17 a-Amylase inhibitors studied recently includeheparin,Q0 l-fluoro-2 : 4-dinitroben~ene,~l and caffeine.Q2a-Amylolysis of amylose has been studied by many workers.l+> s9 l79 93a-Amylases catalyse a random hydrolysis of the non-terminal linkages inamylose (cf., however, ref. 10). The enzymes have a high affinity foramylose, but a much lower affinity for short-chain linear molecules, thedifferences being greatest with malt a-amylase.A study of salivary amylo-lysis of linear maltodextrins has provided further evidence of random attack,73 K. Svanborg and K. Myrback, Arkiv Kemi, 1953, 6, 113.74 S. Schwimmer and A. K. Balls, J . Biol. Chem., 1949, 179, 1063.75 M. L. Caldwell, M. Adams, J. T. Kung, and G. C. Toralballa, J . Amer. Chenz. Soc.,7 7 S. Akabori, B. Hagihara, and T. Ikenaka, ibid., p. 350.7 8 L. A. Underkofler and D. K. Roy, Cereal Chem., 1951, 28, 18.7 9 K. Takaoka, H. Fuwa, and 2. Nikuni, Mem. I n s t . Sci. Res. Osaka, 1952, 10, 199.81 W. J. Whelan and H. Nasr, Biochem. J., 1951, 48, 416.82 P. N. Hobson and M. Macpherson, ibid., 1952, 52, 671.83 D. Scott and L. R. Hedrick, J . Bact., 1952, 63, 795.84 N. I. Proskuryakov and N.V. Dmitri.evskaya, Brit. Abs., 1952, AIII, 1775.85 L. H. Schneyer, Arch. Biochem. Biophys., 1952, 41, 345.8 6 R. L. Lane and R. J. Williams, Arch. Biochem.. 1948, 19, 329.137 E. H. Fischer and P. Bernfeld, Helv. Chim. Acta, 1949, 32, 1146.8 8 M. L. Caldwell, N. Larson, and B. Huston, Cweal Chem., 1952, 29, 463.89 L, H. Schneyer, J . Dental Research, 1952, 31, 767; Arch. Biochem. Biophys., 1952,K. Mryback and B. Person, Arkiv Kemi, 1952, 5, 177.9 1 K. Benner and K. Myrback, ibid., 1952, 4, 7.92 D. Vincent and R. Lagreu, Compt. rend. SOC. Biol., 1950, 144, 1658.93 J. T. Kung, V. M. Hanrahan, and M. L. Caldwell, J . Amer. Chem. Soc., 1953.1952, 74, 4033. 76 B. Hagihara, Proc. Japan. Acad., 1951, 27, 346.S. Schwimmer, Cereal Chem., 1951, 28, 77.39, 65.75, 5548; R.Bird and R. H. Hopkins, Biochem. J., 1954, 56, 86MANNERS : ENZYMIC DEGRADATION OF STARCH AND GLYCOGEN. 295and has shown that the susceptible linkages in a particular substrate arehydrolysed at the same rate.gThe composition of the end-products of such a-amylolyses appears tovary with the particular enzyme preparation used. Amorphous and crystal-line salivary amylase and crystalline A . oryzae amylase (all maltase-free)degrade amylose to maltose (87%) and glucose (13%).941 95 Maltose itselfis not hydrolysed by a-amylases since it is a non-competitive inhibitor; 96the glucose presumably arose from the slow hydrolysis of maltotriose.J. H. Pazur has shown that maltotriose is slowly hydrolysed by unpurifiedsalivary amyla~e.~7 Whelan and Roberts, however, using a purifiedsalivary a-amylase, found maltose and maltotriose in the molar ratio of2.39 : 1, to be the sole end product^.^ Svanborg and Myrback, likewise,have reported that maltotricse is not attacked by salivary amylase.73 Thesediscrepancies may be due to differences in the relative concentrations ofenzyme and substrate, or may imply the existence of a specific “malto-triase ” as an impurity in certain a-amylase preparations.a-Amylolysis of amylopectin is slower than that of amylose, and relativelyhigher enzyme concentrations are required to degrade the a-dextrins toreducing sugars.1-5 The end-products include glucose, maltose, and non-fermentable dextrins, when crystalline A . o ~ y z a e , ~ ~ pancreatic, or malta-amylase is used,98 but maltose, maltotriose, and dextrins when amorphoussalivary amylase is used.s The structures of the dextrins which contain oneor more 1 : 6-linkages, have been discussed in detail.l* *, 99 The smallestbranched dextrin from salivary amylolysis is a pent asaccharide, indicatingthat the three 1 : 4-linkages adjacent to a 1 : 6-linkage are resistant to enzymeact ion.a-Amylolysis of whole starch yields a mixture of maltose (ca.70%),glucose, and dextrins, the exact proportion of each, and the D.P. of thedextrins depending on the source and concentration of enzyme and the timeof digestion. The residual dextrins usually have a D.P. of 5-8, and containa 1 : 6-linkage, since they arise from the amylopectin component ofAlthough all a-amylases catalyse similar reactions, their modes of actionappear to differ in some respects (cf.also ref. 93). There is evidence that,during their respective actions, salivary amylase combines with the exteriorchains of a branched a-dextrin, whilst malt a-amylase combines with theC-chain (see Figure). 73 Furthermore, malt a-amylase liberates glucoseduring the dextrinisation stage of amylolysis, in contrast to A . oryzae 95and pancreatic amylases which liberate glucose only during the sacchari-fication stage, and salivary amylase which produces little or no glucose a tany The action pattern of salivary amylase has now beendefined in detail; 8* similar studies on other a-amylases which are in pro-gress G2 should help to eliminate some of the inconsistencies in present dataon a- am y lo1 y sis .starch.1, 737 95,10094 K. H.Meyer and W. F. Gonon, Helv. Chim. A d a , 1951, 34, 294.O 5 V. M. Hanrahan and M. L. Caldwell, J . Amer. Chem. SOC., 1953, 75, 2191,96 S. Schwimmer, J . Biol. Chem., 1950, 186, 181.97 J. H. Pazur, ibid., 1953, 205, 75.99 K. Myrback, Arkiv Kemi, 1953, 4, 433.K. H. Meyer and W. F. Gonon, Helv. Chim. Acta, 195.1, 34, 308.loo K. Myrback and R. Persson, ibid.. 1953, 5, 365296 BIOCHEMISTRY.Studies on glycogen a-amylolysis are as yet incomplete. B. Carlquist 101has shown that glycogen is degraded by malt a-amylase to a heterogeneousmixture of maltose and linear and branched dextrins. Oyster glycogen onA . oryzae amyolysis gave 57% of maltose, 4% of glucose, and 39% of dextrin(D.P. 8).95 Roberts and Whelan have examined quantitatively the salivarya-amylolysis of pregnant-doe liver glycogen.The products were maltose,maltotriose, and dextrins containing 1 : 6-linkages. Further examination ofthese dextrins provided evidence in favour of a random enzyme action andindicated that the glycogen had a multiply branched structure.8 Bell andManners lo2 found that some of the linkages in the interior chains of rabbit-liver glycogen were resistant to malt a-amylase, but were readily hydrolysedby salivary amylase-further proof that these two a-amylases have differentaffinities for the same substrate.Peat et aL14 have claimed that a sample of rabbit-liver glycogen con-tained ca.2.5y0 of fructose, since on a-amylolysis small quantities of maltulose(ca. 5%) and fructose-containing a-dextrins could be isolated. Otherworkers have been unable to detect fructose in various samples of mammalian-liver glycogen, and a discussion of the significance of this finding must bepostponed until more experimental results are available.Recently a group of " amylases "which produce glucose as the primary product of amylolysis has been dis-covered. These enzymes are not mixtures of a- or p-amylase and maltase.Glucose-forming amylases attack their substrates from the non-reducingterminal groups, and, in stepwise fashion, catalyse the hydrolysis of every1 : 4-gluco-sidic linkage.R. W. Ken- and his co-workers lo3 have purified " amyloglucosidase "from Aspergillus niger.This enzyme had no true a-amylase activity, butconverted maize amylose almost quantitatively into glucose ; with maizeamylopectin ca. 80% conversion to glucose occurred. The rate of hydrolysisof amylopectin was greater than that of amylose, owing to the larger numberof non-reducing terminal groups present in the amylopectin molecule. Astudy of the rate of hydrolysis of amylose suggested (a) a " single-chain "mechanism,lo3 and (b) the existence of a low degree of branching in theamyl0se.~5The so-called " maltase " of Clostridium acetobutylicum has been purifiedby D. French and D. W. Knapp.lo4 This enzyme slowly hydrolysed maltose,maltoheptaose, isomaltose, starch, a- and P-dextrin, and a Schardingerdextrin, to give nearly quantitative yields of glucose.Dextran, however,was not attacked. An examination of the products formed during thehydrolysis of maltoheptaose led these workers to postulate a " multi-chain "action for this enzyme.From the mould Rhzixopus delemar, L. L. Phillips and M. L. Caldwell lo5obtained a purified " gluc-amylase," which catalysed the hydrolysis, toglucose, of maize amylose and amylopectin, waxy maize starch and itsP-dextrin, glycogen, and maltose. I t had no action on isomaltose, dextran,C. " Amylases " producing glucose.101 B. Carlquist, Acta Chem. Scand., 1948, 2, 770.102 D. J. Bell and D. J. Manners, Biochem. J . , 1951, 49, lxxvii.Io3 R. W. Kerr, F. C. Cleveland, and J. Katzbeck, J . Amer. Chem. Soc., 1951, 73, 3916.lo4 D.French and D. W. Knapp, J . Biol. Chem., 1950, 187, 463.lo5 L. L. Phillips and M. L. Caldwell, J . Amer. Chem. Soc., 1951, 73, 3559, 3563MANNERS : ENZYMIC DEGRADATION OF STARCH AND GLYCOGEN. 297or cyclic Schardinger dextrins. Their results suggest that gluc-amylasecannot split 1 : 6-inter-chain linkages, but can by-pass them (cf. a-amylases).“ y-Amylase ” isolated (in partly purified form) from Aspergillus awamoriappears to be a unique glucose-producing amylase.lo6 This enzyme (alsopresent in A . batatae and A . cinnamomeus) liberates p-glucose together with asmall amount of maltose from soluble starch; it apparently has no action onmaltose. Further work is necessary on the amylolytic systems of this groupof moulds.This amylase is unique in that it degradesstarch by a transference rather than a hydrolytic mechanism, to yield amixture of cyclic dextrins.The isolation, purification, properties, and modeof action of B. macerans “ amylase ” have been described recently,15> 107-109and will not be discussed further in this Report.Degradation of a-1 : 4-Linkages by Transferring Enzymes.-Phosphoryl-ases. The phosphorylases catalyse the reversible transfer of a glucosylradical from or-D-glucose 1-phosphate to a chain of a-1 : 4linked glucoseresidues, according to the equation :where [GIn or [GI,+, represents a chain of n or n + m glucose residues,G.l.P. = glucose l-phosphate, and H0.P = inorganic phosphate. Althoughthe equilibrium position of the reaction is in the direction of synthesis, in thepresence of an excess of inorganic phosphate, degradation of an or-1 : 4-glucosan occurs.Phosphorylases have been isolated from many sources ; those fromanimal cells will be referred to as “ phosphorylases ” and those from plantsas “ P-enzymes,” since they differ in several respects, even though theycatalyse similar reactions.Muscle phosphorylase has been crystallised, 110 several recrystallisationsbeing necessary to remove traces of other enzymes.lll It is a conjugatedprotein ; studies on the prosthetic group 112 and amino-acid composition 113have been reported, but the nature of the “ active groups ” and the mechan-ism of its activation by adenylic acid remain unknown.Liver phosphorylasehas been purified by E. W. Sutherland,l14 the active enzyme differing frommuscle phosphorylase in its physical properties, eg., solubility.Liverphosphorylase also occurs in two inactive forms, only one of which is activein the presence of adenylic acid (cf. muscle phosphorylase).In the presence of inorganic phosphate, phosphorylases cause partialdegradation of maize amylose, glycogen, and amylopectin, the limits beingca. 70, 2 8 4 9 , and 36--57% respe~tively.~~, 61y 115 The reason for the in-complete action on amylose may be due to the presence of anomalous link-ages, or to a low degree of branching. With glycogen and amylopectin,106 K. Kitahara and M. Kurushima, Mew. Res. Inst. Food Sci. Kyoto, 1952. 15.107 S. Schwimmer and J . A. Garibaldi, Cereal Chem., 1952, 29, 108.108 S.Schwimmer, Arch. Biochem. Biophys., 1953, 43, 108.log E. Norberg and D. French, J. Amer. Chem. Soc., 1950, 72, 1202.110 A. A. Green and G. T. Cori, J. Bzol. Chem., 1943, 151, 21; G. A. Kritsky and111 G. T. Cori and J. Larner, J. Biol. Chew., 1951, 188, 17.112 M. V. Buell, Fed. Proc., 1952, 11, 192.113 S. F. Velick and L. F. Wicks, J. Biol. Chem., 1951, 190, 741.114 E. W. Sutherland, “ Phosphorus Metabolism,” 1951, Vol. I, p. 58.115 s. Hestrin, J. Bid. Chem., 1949, 179, 943.D. B. macerans “ amylase.”[GI,, + mG.1.P [G]n+m + nzH0.PE. B. Kuvaeba, Brit. Abs., 1951, A, 111, 1284.Johns Hop-kins Press, Baltimore298 BIOCHEMISTRY.phosphorylase action is limited to the exterior chains, since the pure enzymecannot rupture or by-pass 1 : 6-linkages.l15 Furthermore, the affinity ofthe enzyme for the substrate decreases as the exterior chains are shortened.Phosphorolysis of a B-type chain in glycogen (or amylopectin) ceases atabout the sixth residue from the branch point, whereas an A-type chain iscompletely degraded except for a single glucose residue which remainsattached to the B-chain.It is this residue which arrests phosphorolysis ofthe B-chain.lllPotato P-enzyme has been purified by several groups of workers 116, 11’and has now been crystallised.ll8 P-Enzymes do not require adenylic acidfor activity, but the nature of their active centres are as yet unknown. Inpresence of inorganic phosphate, P-enzyme degrades certain amylosescompletely to glucose l-phosphate; 119 with other samples, only 70%degradation occurs.l1 On addition of Z-enzyme, complete degradationfollows, affording additional evidence of p-linkages in these amyloses.11The degradation of amylose by P-enzyme proceeds by a multi-chain mechan-ism.12G The action of P-enzyme on amylopectins is confined to their exteriorchains, the limiting conversion to glucose 1-phosphate (36--5i%) dependingon the sample examined,ll9 and is unaltered by 2-enzyme.ll P-Enzyme hasvery little action on glycogen, presumably owing to its low affinity for therelatively short exterior chains (ca. 8 glucose units as compared with ca. 14units in amy1opectins).l17In presence of arsenate, amylosaccharides are converted by P-enzymesinto glucose.121 The enzymes transfer a glucosyl unit to arsenate, givingthe rapidly decomposing glucose l-arsenate.The limits of P-enzymearsenolysis and p-amylolysis of amylopect ins have been compared byK. H. Meyer et aZ.122 and found to be identical. The speeds, however,differed considerably, p-amylolysis occurring ca. 1000 times as fast a s arseno-lysis (or ca. 100 times as fast as phosphorolysis). Since muscle phosphorylase,but not P-enzyme, limit dextrins are further hydrolysed by @-amylase,P-enzymes and phosphorylases differ in their affinities for the same branchedamylosaccharides. Related differences with respect to specificity of“ primer ” molecules during the synthesis of such polysaccharides have beennoted e1~ewhere.l~. 115Several enzymes are known which can reversiblytransfer a glucosyl unit from a suitable donor to a chain of 1 : 4-a-linkedglucose units, e.g,, amylomaltase, amylosucrase, Schardinger dextrinogenase(B.macerans amylase), and D-enzyme. Since studies on these enzymes havebeen directed mainly to their synthetic, rather than to their degradative,activities, they will not be discussed further in this Report.Degradation of 1 : &Linkages by Hydrolytic Enzymes.-For some timeit has been known that extracts of certain plants, yeasts, or moulds couldhydrolyse the inter-chain linkages in starch-type polysaccharides. OnlyOther transglucosylases.116 S. A. Barker, E. J. Bourne, I. A. Wilkinson, and S. Peat, J . , 1950, 84; G. A.1 1 7 E. H. Fischer and H. M. Hilpert, Experientia, 1953, 9, 177.118 H. Baum and G.A. Gilbert, Nature, 1963, 171, 983.119 J. Katz, W. 2. Hassid, and M. Doudoroff, ibid., 1948, 161, 96.120 J. M. Bailey and W. J. Whelan, Biochem. J . , 1952, 51, xxxiii.lZ1 J. Katz and W. 2. Hassid, Arch. Biochem., 1951, 30, 272.122 K. H. Meyer, R. M. Weil, and E. H. Fischer, Helv. €him. Acta, 1952, 35, 247.Gilbert and A. D. Patrick, Biochem. J.. 1952, 51, 186MANNERS ENZYMIC DEGRADATION OF STARCH AND GLYCOGEN. 299during the past few years, however, have purified “ debranching ” enzymesbeen isolated.R-Enzyme. From the potato and broad bean, S. Peat and hiscolleagues 123 isolated an enzyme (R-enzyme) which hydrolysed the inter-chain linkages in amylopectin and its p-dextrin. Treatment of these sub-strates with R-enzyme increased P-amylolysis by ca.20 and 60% respectively,whilst a mixture of R-enzyme and or-amylase caused complete degradationto linear oligosaccharides. R-Enzyme has no action on amylose, isomaltose,dextran, or glycogen, and has no synthetic activity.AmyZo-1 : 6-ghcosidase. G. T. Cori and J. Larner 111 isolated frommuscle extracts an enzyme, amylo-1 : 6-glucosidase, which, acting togetherwith phosphorylase, caused complete digestion of glycogen and amylopectin.Amylo-1 : 6-glucosidase hydrolysed the single unit remaining from theA-chain in the appropriate phosphorylase limit dextrin, liberating one mol.of glucose. The combined action of phosphorylase and amylo-1 : 6-glucosidase therefore gives glucose 1-phosphate (ca. 95%) together withglucose, the amount of the latter depending on the number of 1 : 6-linkagesin the molecule. The ratio glucose : glucose l-phosphate is therefore ameasure of the degree of branching in the polysaccharide, and the combinedaction of these two enzymes has been used to assay chain lengths of amylo-pectins and glycogens with results in good agreement with methylation andpotassium periodate oxidation assays of the same samples.Less goodagreement was obtained with those from low temperature sodium periodateassays.441 Amylo- 1 : 6-glucosidase slowly hydrolyses isomaltose but hasno action on glycogen or amylopectin.A. N. Petrova 124 has described the presence in rabbit muscle of anenzyme “ amylose isomerase ” which catalyses the degradation and synthesisof 1 : 6-linkages in glycogen.It seems probable that this preparation isa mixture of amylo-1 : 6-glucosidase and muscle branching enzyme, althoughPetrova has repeatedly claimed that “ amylose isomerase ” has a dualfunction. It has been suggested that “ amylose isomerase ” requires athermostable non-protein co-factor for full degradative activity.125In 1940 it was reported 33 that p-amylasein the presence of a brewer’s yeast extract, could further hydrolyse P-dextrinsfrom glycogen and amylopectin. This impure yeast enzyme, called “ amylo-glucosidase,” also hydrolysed maltose and isomaltose.126 More recently, B.Maruo and T. Kobayashi 12’ isolated from autolysed brewer’s yeast an enzymeisoamylase (formerly known as amylosynthease) which hydrolysed the inter-chain linkages in glutinous-rice starch, and an amylopectin (cf.R-enzyme).“ Limit dextrinase.” Although the existence of various “ limitdextrinases ” has been reported, full details of their specificities are not yetavailable. That from A . oryzae has been crystallised.lZ8Structural Analysis of Amylosaccharides by Enzymic Degradations.-Amylolysis is proving a useful method of investigating the structures ofglucosans. Hydrolysis of a glucosan by or-amylase implies the presence of a123 P. N. Hobson, W. J . Whelan, and S. Peat, J., 1951, 1461.A. N. Petrova, Chem. Abs., 1948, 42, 7807; 1952, 46, 2103.125 Idem, ibid., 1953, 47, 1809.lZ6 K. H. Meyer and P. Bernfeld, Helv. Chim. Acta, 1942, 25, 399.lz7 B. Maruo and T. Kobayashi, Nature, 1951, 167, 606.1z8 L.A. Underkofler and D. K. Roy, Cereal Chem., 1951, 28, 18.Yeast “ debranching ” enzymes300 BIOCHEMISTRY.number of a-1 : 4-glucosidic linkages ; examination of the hydrolysis productswill assay the number of these, and will reveal the existence of other types oflinkage if present, eg., 1 : 6 in glycogen,8 and 1 : 3 in isolichenin.129 Degrad-ation by p-amylase indicates that the molecule contains one or more non-reducing chains of a-1 : 4-linked glucose residues ; quantitative studiesprovide a method for determining the length of such chains. Polysaccharidesfrom protozoa 3 8 9 130 and micro-organisms 131 have been characterised in thisway. Furthermore, the activity of branching enzymes can be followed byexamining the action of p-amylase on the products formed from amylose,since these products will have lower P-amylolysis limits than the amylose.132Several enzymic methods of end-group assay of a-1 : 4-glucosans havebeen developed.The combined use of phosphorylase and amylo-1 : 6-glucosidase has already been discussed (p. 299). A method developed byW. J. Whelan 8y 68 involves the preparation of a-dextrins from glycogen oramylopectin and subsequent treatment with R-enzyme. The number ofreducing groups liberated on “ debranching ” equals the number of 1 : 6-linkages present in the original glucosan. A further method of enzymicassay is based on the determination of maltotriose obtained on degrading anamylopectin with a mixture of R-enzyme and F-amylase. It is assumed that,on a statistical basis, one-half of the chains present in the molecule containan odd number of glucose residues and will therefore yield maltotriose.68The successive action of phosphorylase and amylo-1 : 6-glucosidase hasled t o the postulation of a “ tier ” (tree) structure for amylopectin andEach enzyme action removes one “ tier ” of exterior chEins,and the resulting limit dextrin can be isolated and characterised. Thereseems to be little doubt that glycogens are multiply-branched molecules asoriginally suggested by K.H. Meyer.An alternative method of structural analysis involves the action ofR-enzyme on a P - d e ~ t r i n . ~ ~ A polysaccharide with singly branched unit-chains would yield one molecule of maltose or maltotriose from its soleA-chain, together with linear saccharides of D.P.> 6 from the B-chains.A polysaccharide with a multiply-branched structure would give a muchlarger amount of maltose and maltotriose. In the case of waxy maizestarch the observed yield of these sugars was greater than that expectedfrom a singly branched structure, and Peat and his colleagues have con-cluded “ that multiple branching is an intrinsic part of the amylopectinstructure.” It can be shown 133 from their experimental data that the waxymaize starch contains one A-chain to every four B-chains-compare a Meyer‘‘ tree ” structure which requires equal numbers of A- and B-chains. Itappears therefore that glycogens and amylopectins differ in degree of multiplebranching. This suggestion is supported by physico-chemical evidence, e.g.,viscosity 134 and iodine-binding power.135 These indicate fundamentall z O N.B. Chanda, unpublished work.130 E. J. Bourne, M. Stacey, and I. A. Wilkinson, J . , 1950, 2694.131 S. A. Barker, E. J. Bourne, and M. Stacey, J., 1950, 2884; P. N. Hobson and132 A. Bebbington, E. J. Bourne, and I. A. Wilkinson, J., 1952, 246; S. Peat, W. J.133 E. L. Hirst and D. J . Manners, Chem. and I n d . , 1954, 224.134 R. W. Kerr, F. C. Cleveland, and W. J. Katzbeck, -1. Amer. Chem. SOC., 1951,73,111.135 D. M. W. Anderson and C. T. Greenwood, Chem. and Ind., 1953, 642; also un-H. Nasr, J . , 1961, 1855.Whelan, and J. M. Bailey, J . , 1953, 1422.published workGREVILLE AND STEWART : FATTY ACID METABOLISM. 301differences in the arrangement of the unit-chains in glycogen and amylo-pectin ; these polysaccharides should therefore not be regarded as variantsof the same basic structure, differing only in chain length.The use of enzymes of known action pattern in structural investigations ofbranched a-l : 4-glucosans therefore provides methods for the determinationof the degree and type of branching, and for the location of the branch pointsin the unit-chains.Caution is necessary, however, when using a mixtureof two purified enzymes since a synergic reaction may occur; it has beenreported that a-amylases, in the presence of Schardinger dextrinogenase, lo7or R-enzyme,6S behave abnormally, the specificity of the enzymes beingaltered and considerable amounts of glucose liberated.In general, enzymicdegradation studies provide , with certain reservations, a valuable means forstudying the fine structure of starch and glycogen, the results so obtained beingused to confirm and supplement those obtained by purely chemical methods.D. J. M.4. FATTY ACID METABOLISM IN ANIMAL TISSUES.Abbreviations used are : AcAc, acetoacetyl ; AcCoA , S-acetyl-coenzymeA ; AcAcCoA, S-acetoacetyl-CoA ; ATP, ADP, AMP, adenosine tri-, di-,and mono-phosphate; CoA or CoA’*SH, coenzyme A; DPN,,, DPNred,oxidised and reduced coenzyme I ; FAD, flavin-adenine dinucleotide ;TPN,d, reduced coenzyme 11. *C denotes an isotopically labelled carbonatom.Great advances have been made in the understanding of fatty acidmetabolism since the last review in these Reports,2 but much remainsobscure, particularly regarding branched-chain fatty acids and those con-taining an odd number of carbon atoms (odd-C acids).Intermediates haveusually been studied by photometric, isotopic, and enzymic methods, andchemical characterisations are mostly still to be undertaken.Fatty Acid Oxidation.-That many tissues besides liver can oxidise fattyacids, although at considerably differing rates, has been confirmed in vitrowith isotopically labelled substrates and tissue slices.3 By three successiveadvances in technique, fatty acid metabolism has been studied with cell-free particle-preparations, soluble systems, and separated enzymes. Fattyacid oxidation by washed-liver particles was first achieved by Leloir andMuiioz and Leh~~inger.~-* Observations were later extended to kidney lo1 G.D. Novelli, Physiol. Reviews, 1953, 33, 525; Fed. Proc., 1953, 12, 675.2 F. Dickens, Ann. Reports, 1945, 42, 197.3 ( a ) R. P. Geyer, L. W. Matthews, and F. J. Stare, J : Biol. Chem., 1949, 180, 1037;( b ) S. Weinhouse, R. H. Millington, and M. E. Volk, ibid., 1950, 185, 191 ; (c) M. E. Volk,R. H. Millington, and S. Weinhouse, ibid., 1952, 195, 493.4 ( a ) J. M. Muiioz and L. F. Leloir, ibid., 1943, 147, 355; ( b ) L. F. Leloir and J . M.Muiioz, ibid., 1944, 153, 53; (c) L. F. Leloir, Enzymologia, 1947, 12, 263.5 A. L. Lehninger, ( a ) J . Bid. Chem., 1944, 154, 309; ( b ) 1945, 157, 363; (c) 161,413, ( d ) 437; ( e ) 1946, 164, 291, (f) 165, 131; ( g ) 1951, 190, 345; ( h ) Biochem.Soc.Symp., 1952,9,66. 6 A. L. Lehninger and E. P. Kennedy, J . Biol. Chem., 1948,173,753.7 E. P. Kennedy and A. L. Lehninger, ibid., ( a ) 1948, 172, 847; ( b ) 1949, 179, 957;( c ) 1950, 185, 275; ( d ) 1951, 190, 361.8 Idem, “ Phosphorus Metabolism,” Johns Hopkins Press, Baltimore, 1952, Vol. 11,p. 253.10 (a) A. L. Grafflin and D. E. Green, J . Biol. Chem., 1948, 176, 95; ( b ) W. E. Knox,B. N. Noyce, and V. H. Auerbach, ibzd., p. 117; ( c ) R. J. Cross, J. V. Taggart, G. A.Covo, and D. E. Green, ibid., 1949, 177, 655.A. Kornberg, op. cit., p. 245302 BIOCHEMISTRY.and heart Fatty acid oxidation takes place in isolated mito-chondria and not in other cell fractions.7a- l1 Particle oxidising systemsare unspecific, attacking lower loa and higher 7e fatty acids, enoic, dienoic,odd-C, branched-chain, p-0x0-, and D- and L-p-hydroxy-acids, but notynoic, 2- or 3-substituted or dicarboxylic acids.loa Effects of variousfactors on fatty acid oxidation by such systems have been thoroughlystudied, and the findings well reviewed.12? 5h3 These studies showed thatfatty acids must be “ activated ” before being oxidised, and, together withisotopic evidence, indicated that the 2C-units formed by p-oxidation l3 arethe same as those arising from oxidative decarboxylation of pyruvate,i.e., AcCoA.l* A scheme similar to that shown below [(l)] was suggested byBarker and his colleagues 15, l6 as a result of work with Clostridium kluyveriextracts, and by Lynen l7 and his co-workers after discovery of acetyl-coenzyme A.That coenzyme A is involved in fatty acid oxidation inanimal tissues was proved by Drysdale and Lardy,l8, l9 and by Green andhis co-workers,20 who obtained CoA-dependent oxidation of butyrate toacetoacetate in soluble systems from acetone-dried rat-liver mitochondriaand from ox-liver respectively. Finally, confirmation of sequence (1) wassupplied by observations with separated enzymes in the laboratories ofGreen, Lipmann, Lynen, and Ochoa.I I 1RCH,CH,CH,CO,H @ RCH,CH,*CH,*CO*S*CoA’ @R*CH,*CH:CH*CO*SCoA’ ( @ R*CH:CH*CH,CO*SCoA’)-4. L-R.CH,*CH (OH)*CH,.CO*SCoA’ R*CH,COCH,CO-S*CoA’xrr I VVR*CH,COSCoA‘ + CH3*CO.S*CoA’ . . . . . . . . . . (1)Fatty acid is “ activated ” by conversion into the coenzyme A deriv-ative, and then by stages 11-V yields acetyl-coenzyme A, and acyl-coenzymeA with two carbon atoms less.The latter passes through 11-V again, andso on. This is essentially Dakin’s scheme21 applied to coenzyme A deriv-atives instead of free acids.Lynen has used S-acyl derivatives of 2-acetamidoethanethiol j- instead ofcoenzyme A as model substrates. Wave-lengths (mp) of absorption maximaof these and some coenzyme A derivatives,22* 23 together with structuralfeatures to which they are attributed, are : CH,*CO*CH,=CO*S*CH2CH2*NHAc233 (-COOS-), 303 (in alkaline solution, intensified by Mg++, enolate ion);11 W. C. Schneider, J . Biol. Chem., 1948, 176, 259.1, D. E. Green, Biol. Reviews, 1950, 26, 410.13 S. Weinhouse, G. Medes, and N.F. Floyd, J . Biol. Chem., 1944, 155, 143.14 S. Korkes, A. del $mpillo, and S. Ochoa, ibid., 1952, 195, 541.l5 H. A. Barker, in Phosphorus Metabolism,” Johns Hopkins Press, Baltimore,1951, Vol. I, p. 204. l6 E. R. Stadtman, Fed. Proc., 1953, 12, 692.17 F. Lynen, E. Reichert, and L. Rueff, Annulen, 1951, 574, 1.18 G. R. Drysdale and H. A. Lardy, in “ Phosphorus Metabolism,” Johns HopkinsPress, Baltimore, 1952, Vol. 11, p. 281.l8 G. R. Drysdale and H. A. Lardy, J . Biol. Chem., 1953, 202, 119.*O See H. A. Mahler, in Phosphorus Metabolism,” Johns Hopkins Press, Baltimore,1952, Vol. 11, p. 286.“21 H. D. Dakin, Oxidations and Reductions in the Animal Body,” Longmans,Green and Co., London, 1912.23 F. Lynen and S. Ochoa, Biochim. Biophys.Actu, 1953, 12, 299. t Added in proof. In the nomenclature proposed by 2. M. Bacq, J . Baddiley, L.Eldjarn, F. Lipman, and F. Lynen (Science, 1954, 119, 163) this is AT-acetylcysteamine.22 F. Lynen, Fed. Proc., 1953, 12, 683GREVILLE AND STEWART : FATTY ACID METABOLISM. 303CHMe:CH*CO*S*CH,*CH,*NHAc, 263 (?-COS-), 224 (CX) ; S-acyl- andp-hydroxyacyl-coenzyme A, 233* (-COOS-) ; S-acetoacetyl-coenzyme A,303 (as with acetamidoethanethiol compound) ; S-crotonyl-coenzyme A,263* (?-COOS-), 224* (CX). In addition, the coenzyme A derivativesabsorb strongly around 260 mp (adenine), which obscures maxima marked * ;these are, however, measured with an equivalent amount of alkali-hydrolysedmaterial in the spectrophotometer reference cell (alkali hydrolyses thiol-esters).Some thiol-esters needed for enzyme studies have been prepared chemic-ally : (i) From thiols and diketen (CH,*CO*CH,*CO*S*CH,.CH,.NHAc andthe coenzyme A derivative23); (ii) from coenzyme A and acid anhydride(S-s~ccinyl-,~~ a ~ e t y l - , ~ ~ and crotonyl derivatives 26) ; (iii) from coenzyme Aand acyl(thiopheno1) 27 (S-acetoacetyl and p-hydroxybutyryl derivatives) ;(iv) from the lead salt of acetamidoethanethiol and acyl chloride (S-crotonylderivative 2s) ; and (v) from coenzyme A and thiol-acids (S-acetyl-,25 S-b ~ t y r y l , , ~ and S-palmityl derivatives 3011).S-Derivatives of coenzyme Ahave also been prepared by using various enzymes described below (seesummary 31a and refs. 32, 30a, and 31b).Reactions applied to determination of acyl derivatives of coenzyme Aformed enzymically include : (a) Hydroxamic acid formation,33 usuallywith hydroxylamine present during the enzyme reaction.34 (b) Acetylationof sulphanilamide 351 l7 or aminoazobenzenesulphonate 36 (pigeon-liver frac-tion added). (c) For acetyl-coenzyme A, arsznolysis in presence of trans-a c e t y l a ~ e .~ ~ ( d ) Nitroprusside reaction, to measure disappearance of thethiol group of coenzyme A. (e) Oxaloacetate + acetyl-coenzyme A __tcitrate (condensing enzyme added ; citrate determined).37 ( J ) Malate +DPN,, oxaloacetate + DPN,d ; oxaloacetate + acetyl-coenzyme A - citrate (malic dehydrogenase and condensing enzyme added ; DPN,ddetermined).38 Acyl-thiols 39 and also hydroxamic acids 40 may be separatedby paper-chromatography .I.Fatty-acid Activation.-(i) Acetate. Acetate is activated ” byextracts of animal tissues in presence of ATP 41*35 and coenzyme24 E. J . Simon and D. Shemin, J . Amer. Chem. Soc., 1953, 75, 252C.25 I . B. Wilson, ibid., 1952, 74, 3205.2 * J. R. Stern and A. del Campillo, ibid., 1953, 75, 2277.2 7 T. Wieland and L. Rueff, Angew. Chem., 1953, 65, 186.28 W. Seubert and F. Lynen, .J. Amer. Chem. Soc., 1953, 75, 2787.28 E. R. Stadtman, J . Biol. Chem., 1953, 203, 501.30 A. Kornberg and W. E. Pricer, ibid., 1953, 204, ( a ) 329, ( b ) 345.31 H. Beinert, ( a ) Fed. Proc., 1953, 12, 681; ( b ) J . Biol. Chem., 1953, 205, 575.32 H. Beinert and P. G. Stansly, ibid., 1953, 204, 67.33 F. Lipmann and L. C. Tuttle, ibid., 1945, 159, 21.34 T.C. Chou and F. Lipmann, ibid., 1952, 196, 89.35 F. Lipmann, ibid., 1945, 160, 173.36 &I. E. Jones, S. Black, R. M. Flynn, and F. Lipmann, Biochim. Bioplzys. Acts,3 7 S. Ochoa, J. 13. Stern, and M. C. Schneider, J . Biol. Chem., 1951, 193, 691.3* J . R. Stern, B. Shapiro, E. R. Stadtman, and S. Ochoa, ibid., p. 703.3~7 E. R. Stadtman, ibid., 1952, 196, 535.40 K. Fink and R. M. Fink, Proc. SOC. Exp. Biol., hT.Y., 1949, 70, 654; E. R. Stadt-4 1 D. Nachmansohn and A. L. Maciiado, J . Neurophysiol., 1943, 6, 397.42 N. 0. Kaplan and F. Lipmann, .I. Biol. Chem., 1948, 174, 37.43 M. Soodak and F. Lipmann, ibid., 1948, 175, 999.44 J. R. Stern and S. Ochoa, ibid.. 1949, 179, 491; 1951, 191, 161.1953, 12 141.man and H. A.Barker, J . Biol. Chem., 1950, 184, 769304 BIOCHEMISTRY.forming acetyl-coenzyme A.34 The reaction catalysed by preparations fromyeast ,459 36 pigeon liver,45, 36 and mammalian heart muscle 46-48 involvespyrophosphoryl scission of ATP (cf. ref. 49) :AcO- + CoA + ATP @ AcCoA + AMP + pyrophosphate(Pyrophosphate breakdown by contaminating pyrophosphatase 50 may beprevented by fluoride.45, 36) Reaction (2) is rever~ible,~~, 47, 4 8 9 51 the equili-brium constant [AcCoA] [AMP][pyrophosphate]/[AcO-][ATP][CoA] beingapproximately 2 ~ 5 , ~ ~ in conformity with calculations 3 8 9 39 that the freeenergy of hydrolysis of the -C(O)-S- bond of acetyl-coenzyme A is com-parable with that of each pyrophosphate bond of ATP. The enzymes fromyeast 369 52 and pig heart 48 have been partially purified, and also that fromox-heart particles.47 Only acetate and propionate are activated ; 481 529 47Mg++ is necessary; 3 6 3 4 8 K+, NH4+, and Rb+ stimulate, whilst Na+ and Li+inhibit strongly.53 The formulation of reaction (2) with coenzyme A-pyro-phosphate as intermediate 45, 54 could not be c0nfirmed,~61 48, 52 and the onenow proposed 55 is (E = enzyme) :.(2)E + ATP-E-AMP + Pyrophosphate . . . (3)E-AMP + HS*CoA’-E-SCoA’ + A M P . . . . . . (4)E-SCOA’ + A c O - - d E + Ac.S*COA’ . . . . . . ( 5 )Evidence for this, obtained with purified yeast enzyme, follows. Forreaction (3) : ATP equilibrates rapidly with 32P-pyrophosphate in absenceof coenzyme A (excluding coenzyme A-pyrophosphate as intermediate).For (4) : coenzyme A inhibits this exchange reaction, presumably by lower-ing the E-AMP concentration.For (5) : labelled acetate equilibrates withacetyl-coenzyme A, at a rate unaffected by AMP addition. Mg++ is neededfor (3), but not for (5).Mahler and his co-workers 56-58 have separatedfrom ox-liver mitochondria an enzyme (“ fatty acid activating enzyme ’I)which activates C4-Cll fatty acids (optimum C,) by a reaction analogous to(2). I t appeared homogeneous in the ultra-centrifuge, but not on electro-phoresis. Mg++ (or Mn++) is needed; Na+ does not inhibit the reaction.The equilibrium constant with heptanoate is about 1, indicating again thatthe free energy of hydrolysis of acyl-coenzyme A is comparable with that ofATP. Enzyme activity increases linearly with pH.Unsaturated, branched-chain, phenyl-substituted, and p-hydroxy-acids are activated ; dicarboxylic(ii) Lower fatty acids.45 F. Lipmann, M. E. Jones, S. Black, and R. M. Flynn, J . Amer. Clzem. SOL., 1952,4 6 D. E . Green, Science, 1952, 115, 661.4 7 M. P. Hele, Fed. Proc., 1953, 12, 216; J. Biol. Chem., 1954, 208, 671.4 8 H. Beinert, D. E. Green, P. Hele, H. Hift, R. W. Von Korff, and C. V. Ramakrish-49 W. K. Maas and G. D. Novelli, Arch. Biochem. Biophys., 1953, 43, 236.50 K. Bailey and E. C . Webb, Biochem. J . , 1944, 38, 394.51 M. E. Jones, Fed. Proc., 1953, 12, 708.52 F. Lynen, Bull. SOL. Chim. biol., 1953, 35, 1061.53 R. W. Von Korff, J . Biol. Chem., 1953, 203, 265.54 D. M. Needham, Ann. Reports, 1952, 40, 275.55 M.E. Jones, F. Lipmann, H. Hilz, and F. Lynen, J . Amer. Chem. Soc., 1953, 15,j7 H. K. Mahler, ibid., p. 694.5 8 H. R. Mahler, S. J. Wakil, and R. M. Bock, J . Biol. Chem., 1953, 204, 453.74, 2384; J. Cell. Comp. Physiol., 1953, 41, SuppI. 1, 109.nan, ibid., 1953, 203, 35.3285. 56 S. Wakil and H. R. Mahler, Fed. Proc., 1953, 12, 285GREVILLE AND STEWART FATTY ACID METABOLISM. 305and amino-acids are not. Formation of coenzyme A derivatives from fattyacids,ls crotonic, and D- and L-p-hydroxybutyric acids 59 has been shownalso in rat-liver mitochondria extracts. Butyrate is said to be activated byreaction with succinyl-coenzyme A.57Kornberg and Pricer 9 7 3oa have found thatsoluble and small-particle fractions of guinea-pig liver convert higher fattyacids ( e g ., myristic, palmitic, stearic) into coenzyme A derivatives, again bya reaction analogous to (2). Mono-, di-, and tri-enoic C,, acids were alsoactivated.11. Acyl-coenzyme A Dehydrogenation.-This is reversible, and in theirenzyme assay Seubert and Lynen 28 measured oxidation of leuco-safraninewith 2-acetamido-l-crotonylthioethane as model substrate. Their enzyme,from sheep liver, was yellow and a FAD-protein. I t was named “ ethylenereductase ” by analogy with the FAD-protein “ Fumarat-Hydrase.” 6OCrotonate was not activated ; DPN,,d or TPN,d would not replace leuco-dye.Mahler and his co-workers. 57, 61, 62 prepared from ox-liver mitochondria‘‘ butyryl-coenzyme A dehydrogenase,’ a vivid green FAD-protein , homo-geneous on electrophoresis and ultra-centrifugation.It catalyses dehydro-genation of coenzyme A derivatives of fatty acids from C, to C, (C, optimum ;feeble activity with CJ. It is uncertain whether butyryl-coenzyme A yieldscrotonyl- or vinylacetyl-coenzyme A ; probably it is the former, sincepropionyl-coenzyme A is acted upon. The enzyme, reduced by sodiumdithionite or by butyryl-coenzyme A, is rapidly re-oxidised by crotonyl-coenzyme A. Onaddition of butyryl-coenzyme A the extinctions a t 355, 432, and 685 mp aredecreased. The enzyme contains bound copper (1 Cu : 2 flavin) ; on dialysisagainst potassium cyanide solution the 685-mp peak, not seen with otherflavoproteins, disappears ; it is attributed to copper-enzyme bonding.Cyanide-treated enzyme catalyses dehydrogenation of butyryl-coenzyme Awith 2 : 6-dichlorophenolindophenol (a two-electron acceptor), but not withcytochrome c or ferricyanide (one-electron acceptors) unless the cyanide-treated enzyme is first incubated with CuiT.Mahler implies that theenzyme-bound copper probably transfers electrons from reduced flavin toan unidentified, one-electron acceptor in the cell. A yellow “ acyl-coenzymeA dehydrogenase,” also from ox-liver mitochondria , catalyses dehydrogen-ation of coenzyme A derivatives of higher fatty acids (C, and111. Enoyl-coenzyme A Hydration.-Existence of an enzyme ( ‘ I croton-ase,” 26 “ a$-unsaturated acyl-coenzyme A hydrase ” 57) which catalysesS-crotonyl-CoA + H,O S-$-hydroxybutyryl-CoA was indicated byexperiments 26 with heart and liver fractions. The ox-liver enzyme hasbeen partially purified in Green’s 62, 57 and Ochoa’s 239 52 laboratories.Inassays with crotonyl-coenzyme A as substrate, hydration was measured by(a) DPN reduction in presence of p-hydroxyacyl-coenzyme A dehydrogenase(iii) Higher fatty acids.Absorption maxima are at 265, 355, 432, and 685 mp.6250 A. L. Lehninger and G. D. Greville, J . Amer. Chem. Soc., 1953, 75, 1515; Biochim.Biophys. Acta, 1953, 12, 188.6o F. G. Fischer and H. Eysenbach, Annalen, 1937, 530, 99 ; K. P. Harrison, Nature,1953, 172, 509.81 H. R. Mahler, J . Amer. Chem. Soc., 1953, 75, 3288; J . Biol. Chem., 1954,206, 13;D. E. Green, S. Mii, H. R. Mahler, and R. M. Bock, ibid., p. 1.62 H. Beinert, R.M. Bock, D. S. Goldman, D. E. Green, H. R. Mahler, S. Mii, P. G.Stansly, and S. J . Wakil, J . Amer. Chem. Soc., 1953, 75, 4111306 BIOCHEMISTRY.(see reaction 6),57 or (b) decrease in absorption at 263 m ~ , * ~ ? 52 which corre-sponds to a maximum for crotonyl- but not for p-hydroxybutyryl-coenzymeA (p. 302). The enzyme hydrated the coenzyme A derivatives of all2 : 3-unsaturated acids tested (C4-C,2),57 but not 2-acetamido-l-crotonyl-thioethane, ~ r o t o n a t e , ~ ~ ~ 52 or cis-but-2-enoyl-coenzyme A 62 (cis-but-2-enoate is, however, oxidised by liver particles lea). I t is specific for thecoenzyme A derivative of L-( +)-p-hydroxybutyric acid,57 and presumablyof the L-isomers of other p-hydroxy-acids. Vinylacetyl-coenzyme A reacts,57so an equilibrium must be set up between crotonyl, vinylacetyl, and p-hydr-oxybutyryl derivatives.At equilibrium at pH 9.0 [total butenoyl-co-enzyme A]/[L-p-hydroxybutyryl coenzyme A] = ca. 0-7.62IV. p-Hydroxyacyl-coemyme A Dehydrogenation.-The enzyme (“ p-keto-reductase,” 63 “ p-hydroxyacyl-coenzyme A dehydrogenase ” 62) whichcatalysesS-/3-Hydroxybutyryl-CoA + DPN,, AcAc-CoA + DPXRd . (6)was purified from sheep liver by Lynen and his c o - ~ o r k e r s , ~ ~ using as assayoxidation of DPNred by 2-acetamido-l-acetoacetylthioethane. With theenzyme, acetyl-CoA, and p-ketothiolase contained in a liver fraction (seebelow), acetoacetyl-coenzyme A was reduced to the p-hydroxybutyryl deriv-ative at the expense of the nucleotide. The same reduction was effected bya pig-heart fraction.64b In Green’s laboratory, the enzyme was purified fromox-liver mitochondria ; 5 7 9 62 the coenzyme A derivatives of the p-hydroxy-acids tested (C4--C1?) were all oxidised at about the same rate; p-oxoacyl-coenzyme A derivatives were formed.Acetoacetate 23 and S-acetoacetyl-glutathione 65 were not activated. DPN can be replaced by coenzyme III,66but not by TPN.62 The enzyme is specific for the coenzyme A derivative ofL-( +)-p-hydroxybutyric acid,59, 62 and presumably of the L-isomers of theother p-hydroxy-acids. p-H ydroxybutyric dehydrogenase is specific forthe D-(-)-isomer of the free acid.67 Rat liver converts L-p-hydroxybutyrateinto a coenzyme A derivative, so particulate preparations oxidise it via thetricarboxylic acid cycle, whilst the D-salt is converted largely into aceto-a~etate.5~ The equilibrium position of reaction (6) is dependent on hydrogen-ion c~ncentration,~~ as with other DPN-linked dehydrogenase reactions,owing to changing ionisation of DPNred over a certain pH range.Thus it isstrongly on the side of hydroxy-compound at pH 7, but shifts in favour ofacetoacetyl-coenzyme A as the pH rises.63, 579 23V. p-Oxoacyl-coenzyme A Cleavage (Thiolysis) .-The finding that thecoenzyme-A-catalysed synthesis of acetoacetate from acetate 43 involvescondensation of two ‘ I activated ” 2 C - ~ n i t s , ~ ~ and evidence that acetoacetateforms citrate via acetyl-coenzyme A,44 indicated the reversible reaction :AcAc-S-COA’ + Coh’*SH 2Ac-S-COA’ .. . . (7)The names “ p-ketothiolase,” 63 ‘ I acetoacetate condensing enzyme,” 64 and“ AcAcCoA cleavage enzyme ” 62 have been proposed for an enzyme cata-63 F. Lynen, L. Wesely, 0. Wieland, and L. Rueff, Angew. Chem., 1952, 64, 687.64 J . R. Stern, M. J . Coon, and A. del Campillo, (a) Nature, 1953, 171, 28; ( b ) J .6 5 T. Wieland and H. Koppe, Annalew, 1953, 581, 1.6 6 T. P. Singer and E. B. Kearney, Biochzrn. Biophys. Acla, 1952, 8, 700; 1953,67 D. E. Green, J. G. Dewan, and L. F. Leloir, Biochem. J., 1937, 31, 934.0 8 E. R . Stadtman, M. Doudoroff, and F. Lipmann, J. Bid. Chew., 1951, 191, 377.Amer. Chem. SOC., 1953, 75, 1517.11, 290GREVILLE AND STEWART FATTY ACID METABOLISM. 307lysing this reaction. Acetoacetyl-coenzyme A formation by a sheep-liverfraction was studied by Lynen and his co-workers 63 as indicated under (IV).Acetoacetate formation from acetyl-coenzyme A was shown with an ox-liverpreparation.64 Thiolysis has been studied in conjunction with the trans-ferzse (see section VI below) which supplies acetoacetyl-coenzyme A byreaction between acetoacetate and succinyl-coenzyme 697 709 64* Thio-lysis has been measured by decrezse in absorption at 305 mp due to dis-appearance of acetoacetyl-coenzyme A,64b9 23 increase in absorption at240 mp accompanying formation of a second -CO-S- bond,23 citrate form-ation (method e , p.303),64* and DPN reduction (method f, p. 303).57Formation of acetoacetyl-coenzyme A from the acetyl derivative a t pH 9 isshown by increase in absorption a t 305 mp.52 An enzyme purified from pigheart was most active with acetoacetyl-, but inactive with p-oxohexanoyl-coenzyme A ; 23 an enzyme purified from ox-liver mitochondria functionedwith coenzyme A derivatives of all p-lteto-acids tested (C4-C8).699 57 Theequilibrium position of reaction (7) is far towards cleavage : 63, 646 at equili-brium [ACCOA]~/[A~ACCOA][COA] = 5 x lo4 at pH 8.1, and 1 x lo4 atpH 9*0.23Evidence has been provided 22y 23 that p-ketothiolase is an “ SH-enzyme,”and the following mechanism (HS*E = enzyme) has been suggested :RCH,*COCH,CO*S*CoA’ + HS-E @ R.CH,.CO.S-E + CH,*CO.SCoA’ . (8)R*CH,*CO*S.E + HS*CoA’ R*CH,.CO.S*CoA’ + HS-E .. (9)Some support for reaction (9) is given by the finding that 35S enters pro-pionyl-coenzyme A when this is incubated with H35S*CoA’ and enzyme.Apossible formulation of reaction (S), when RCH, = Me, is :E*S.C+-O- + H+-C-H,CO.S*CoA’ E*SC(OH) *CH,*CO*S-CoA’ -- Me MeESH + Me.COCH,.CO.S.CoA’ . . . . . . ( 10)This conforms with Lynen’s view22 of the methyl activation of acetyl-coenzyme A, for which he finds support in the low pK for enol ionisationof acetoacetyl-coenzyme A. Beinert and S t a n ~ l y , ~ ~ unaware of the thiolgroup in the enzyme, have proposed a mechanism somewhat different fromthat indicated by reactions (8) and (9) (p. 315).VI. Acetoacetate Formation.-There is said 57 to be in liver a specificAcAcCoA-rr deacylase ” which catalyses hydrolytic formation of aceto-acetate; details have not been given. In heart, and probably in skeletalmuscle and kidney, but not in liver, acetoacetate may be “ activated ”(p. 313) by the 70, 699 64 AcAcO- + succinyl-CoA + + AcAcCoA +succinate, catalysed by ‘‘ succinyl-CoA-AcAcO- transferase.” The equili-brium is greatly in favour of acetoacetyl-coenzyme A formation.The pig-heart enzyme has been considerably purified and freed from P-ketothiolase ; 23it activates c4-c6 (not C )“ Reconstructed Syste&.”-Butyrate has been converted into acetyl-coenzyme A, and thence into citrate, by a mixture of the enzymes describedketo-acids.69 D. Goldman, Fed. Proc., 1953, 12, 209.70 D. E . Green, D. S. Goldman, S. Mii, and H. Beinert, J . Biol. Chem., 1953, 202, 137308 BIOCHEMISTRY.in sections I-V, together with ATP, coenzyme A, malate, malic dehydro-genase, condensing enzyme, DPN , diaphorase , pyocyanine, and triphenyl-tetrazolium salts (final electron-acceptor).62 Synthesis of butyryl-coenzymeA from the acetyl derivative has been achieved with an appropriate mixtureof enzymes, and DPN,d and reduced “ benzyl viologen ” as hydrogen donorsfor (IV) and (11) re~pectively.7~‘ I Sparking ” aazd “ Priming.” 12, 5h3 Washed-particle preparationsoxidise fatty acids through the tricarboxylic acid cycle and also convertthem into acetoacetate.If increasing concentrations of an intermediate inthe cycle (e.g., malate) are added, acetoacetate formation becomes pro-gressively less and oxidation via the cycle greater,6 since more oxaloacetateis provided to react with the acetyl-coenzyme A from the fatty acid(“ sparking ”-Green).Particularly with aged or exhaustively washedparticles, fatty acids are not attacked until tricarboxylic acid cycleintermediates are added in low concentration, whereupon acetoacetate isformed.6. lob This phenomenon is also called ‘ I sparking ” by Green, butshould perhaps be distinguished as I ‘ priming ” (Lehninger). Several find-ings indicate that priming is concerned with initial “ activation ” of fattyacids, i.e., conversion into acyl-coenzyme A with the aid of ATP : (i) 2 : 4-Dinitrophenol and gramicidin , which inhibit oxidative formation of ATP,also stop fatty acid oxidation loC a t concentrations which scarcely affectoxidation of intermediates in the cycle. (ii) Priming is achieved by additionof DPN,d,7d oxidation of which results in ATP formation.72, 5g (iii) Fattyacid oxidation results in ATP formationJ6 and continues after all the DPNpdhas been oxidised in (ii) ( ‘ I self-priming ” (iv) Priming is needed foroxidation of p-keto- , ap-unsaturated,12 and p-hydroxy-acids.59 Priming isnecessary despite presence of added ATP (see, however, ref. 73), and is notrequired in soluble systems, which are unaffected by dinitrophenol. la I tseems, therefore, likely that priming provides ATP at some site in mito-chondria usually inaccessible to external ATP. Addition of ATP is neces-sary for most metabolic reactions with mitochondria, but possibly tomaintain their integrity, since it prevents 74 and reverses 75 swelling.Fluoride inhibits fatty acid oxidation in particles*” and not in solublesystems; la it may also affect priming (by preventing pyrophosphatescission ?).Fatty Acid Synthesis.-The first evidence by that carbohydrate __+ fatconversion in animals 76 occurs by condensation of ZC-units came from theuse of isotopes,77 which also showed that a considerable part of dietarycarbohydrate is normally converted into fat.78 Incorporation of *C fromacetate into fatty acids in vitro has been shown with slices of liver,79> 81a12).71 P. G. Stansly and H. Beinert, Biochim. Biophys. Acta, 1933, 11, 600.74 M. Friedkin and A. L. Lehninger, J . Biol. Chem., 1949, 178, 611.73 J . D. Judah and K. R. Rees, Biochem. J . , 1953, 55, 664.74 J. Raaflaub, Helv. Physiol. Pharmacol.Acta, 1953, 11, 142, 157.75 J . B. Chappell, personal communication.76 J . B. Lawes and J . H. Gilbert, Phil. Mag., 1866, 32, 439.7 7 R. Schoenheimer, “ The Dynamic State of Body Constituents,” Harvard Univ.7 8 Dew. Stetten and G. E. Boxer, J . Biol. Chem., 1944, 155, 231.7 9 K. Bloch, E. Borek, and D. Rittenberg, ibid., 1946, 162, 441.8o K. Bloch and W. Kramer, ibid., 1948, 173, 811.Press, Cambridge, Mass., 1946, p. 3.R. 0. Brady and S. Gurin, ( a ) i b i d . , 1950, 186, 461; ( b ) 1950, 187, 589GREVILLE AND STEWART : FATTY ACID METABOLISM. 309kidney, heart, spleen, testis,82 and mammary gland; 8s so has incorporationof 14C from glucose with liver, kidney, diaphragm,g4 and mammary gland,85$ 86and of deuterium from D20 in adipose t i ~ s i l e .~ ~ Incorporation of 14C-acetateinto long- and short-chain fatty acids has been shown in homogenates,88> 89aand in pigeon- and rat-liver 91 soluble systems obtained by mixing “ cell-sap ” material with the soluble components from lysed mitochondria. Incontrast, with lactating rat mammary tissue the complete incorporationsystem seems to be in the “ cell sap.” 8 9 b 9 c Finally, butyryl-coenzyme Ahas been formed from the acetyl derivative in a system containing purifiedenzymes (p. 308).71Mechanism.-Addition of a 2C-unit to C(l) of 14C<,>-myristate has beenshown in rats,92 and of CH,-14C0,- to Ccl> of endogenous palmitate in vimand in ~ i t r o . ~ ~ Evidence that short-chain fatty acids derived fromCH,*14C02- are formed by addition of 2C-units to the C(,,-position wasobtained with mammary gland; 94, 95 C(w-l) and C(w-3) had equal activities,lower than those of C(,,, C,,,, etc., probably as a result of dilution of[ 1 : 3-14C] acetoacetyl-coenzyme A by endogenous unlabelled p-hydroxy-butyryl-coenzyme A.Earlier suggestions that a 3C-unit may be incorporated as such into fattyacids during synthesis 9 6 j 97 have not been confirmed : (1) *C(3)- and *Cf2)-pyruvate yield the same isotope distribution in fatty acids as do *CH3*C02-or CH3**C02- ; s5t 95 and CH,-CH(OH)*14C02- contributes no 14C to fattyacidsg8 (2) Appearance of [ l-14C]glucose almost entirely in even-numberedcarbon atoms of octanoate 959 86 suggests glycolysis followed by pyruvatedecarboxylation. (3) Synthesis of 14C-butyryl-coenzyme A fromCH3J4CO*S*CoA’ (p.308) 71 leaves little doubt that the key reaction in fatsynthesis is repeated condensation of acetyl-coenzyme A with R*CO*S-, andthat pyruvate merely provides acetyl-coenzyme A, unless two syntheticpathways exist, one using acetyl-coenzyme A and the other the pyruvate.Occasionally *C-AcQ- is not incorporated into fatty acid, but it is whenpyruvate is added as well ; *O, 99 in these cases acetate might not be activatedin the absence of energy available from pyruvate oxidation. Pyruvatemight also act by enlarging the acetyl-coenzyme A pool, with consequentreduction of 14C02 formation by the tricarboxylic acid cycle, if the size ofthe pool affects rate of fatty acid synthesis more than that of carbon dioxideformat ion.82 G.Medes, A. Thomas, and S. Weinhouse, J . Biol. Chem., 1952, 197, 181.83 J. H. Balmain, S. J. Folley, and R. F. Glasscock, Biochem. J . , 1952, 53, 301.84 S. S. Chernick, E. J. Masoro, and I. L. Chaikoff, Proc. Soc. E x p . Biol., N.Y.,8 6 G. Popjak, G. D. Hunter, and T. H. French, ibid., 1953, 54, 238. *’ B. Shapiro and E. Wertheimer, J . Biol. Chem., 1948, 173, 725.88 N. L. R. Bucher, J . Amer. Chem. SOC., 1953, 75, 498.89 G. Popjcik and A. Tietz, ( a ) Biochem. J . , 1954, 56, 46; ( b ) ibid., 1954, p. xxiii;so R. 0. Brady and S. Gurin, J . Biol. Chem., 1952, 199, 421.91 F. Dituri and S. Gurin, Arch. Biochem. Biophys., 1953, 43, 231.O e H. S. Anker, J . Biol. Chem., 1952, 194, 177.D4 G. PopjAk, G. D.Hunter, and T. H. French, Biochem. J., 1953, 54, 238.95 G. PopjAk, Biochem. Soc. Symp., 1952, 9, 37.O 6 I . Smedley-MacLean, “ The Metabolism of Fat,” Methuen, London, 1943, p. 21.9 7 I<. Bloch, Cold SFring Harbor Symp., 1948, 13, 29.9 8 J . M. Felts, I. L. Chaikoff, and M. J . Osborn, J . Biol. Chem., 1951, 191, 683.s9 W. Shaw and S. Gurin, Arch. Biuchem. Biophys., 1953, 47, 220.1950, 73, 348.., 8 5 T. H. French and G. Popjkk, Biochem. J . , 1951, 49, iii.( c ) Biochim. Biophys. Acla, 1953, 11, 587.93 I. Zabin, ibid., 1951, 189, 355310 BIOCHEMISTRY.The mechanism of carbohydrate + fat conversion may be reviewed interms of the hypothetical equation :(4 (b)4Hexose (24C) --+ 8C0, .__+ lPalmitate (16C) + 8C0, ] (11)+ 8AcCoA 8CoA + 8ADP + 8ATP[:::N, j + [ EE&, -j [ 14DPN,, + ZDPN,,jCoenzyme A, ATP, and DPN are needed loo for incorporation of CH3J4C0,- ;with acetyl-coenzyme A as substrate instead of acetate, ATP is unnece~sary.~~The overall change may be divided into two steps : (a) catabolic, furnishingunits and energy for synthesis, and (b) anabolic, with C-C bond formationand hydrogenation, giving the paraffinic acid.The citrate required bysoluble systems 9 0 9 917 In thereconstituted system DPN,d does not react with butyryl-coenzyme Adehydr~genase,~~ but some intermediary may exist in the cell.Efect of Fasting and Diabetes.-(i) Short fasts (e.g., 1 day) suppressincorporation of *C-acetate into fatty acids in rats lol and in rat 9 7 7 lo2> 82(but not cat slb)-liver slices.(ii) [14C]Glucose fails to be incorporated withslices from rats fed on a high-fat or protein diet.lo31 lo* (iii) Uptake of 14Cfrom acetate and glucose into fatty acids is impaired in liver slices fromdepancreatised cats 81b* lo5 and alloxan-diabetic rats8lb9 lo6 With the latter,oxidation of [14C]glucose to carbon dioxide is also suppressed.lo6 Insulinpre-treatment of the rats restores the oxidative and lipogenic pathways; lo'but addition of insulin to the slice has no effect,*lb although it acceleratesincorporation in normal slices.801 81a (Incorporation is reduced in liverslices of " Houssay " cats injected with pituitary growth-h~rrnone.~~~)(iv) Feeding fructose (but not glucose) to diabetic rats for three days beforekilling them restores the ability of the liver slice to incorporate 14C into fattyacids from acetate and lactate, but not from glucose.lo8 These findings,taken with other evidence,log indicate that one defect in fat synthesis fromglucose in the diabetic or fasted rat arises from failure of glucose toreach or to be activated by hexokinase (fructcse seems to be less affected).A second defect is indicated by two findings : (a) [14C]fructose, added todiabetic rat-liver slices, is not incorporated into fatty acids, even though itis converted into carbon dioxide at a normal rate; log and (b) prolongedfasting (2 and 3 days) of normal rats impairs incorporation by liver slicesof 14C from fructose into fatty acids, but not into glycogen or carbondioxide.l1° In (b), glycolysis and the tricarboxylic acid cycle are (pre-is possibly used for reduction of DPN,,.loo J.Van Baalen and S. Gurin, J . Biol. Chem., 1953, 205, 303.lol J. T. Van Bruggen, T. T. Hutchens, C. K. Claycomb, W. J. Cathey, and E. S.West, ibid., 1952, 196, 389; J. G. Coniglio, C. E. Anderson, and C. S. Robinson, ibid.,l o Z I. Lyon, M. S. Masri, and I. L. Chaikoff, ibid., 1952, 196, 25.lo3 E. J. Masoro, I. L. Chaikoff, S. S. Chernick, and J. M. Felts, ibid., 1950, 185, 845.lo4 I. L. Chaikoff, Harvey Lectures, 1952, Vol. XLVII, p. 99.lo5 R. 0. Brady, F. D. W. Lukens, and S. Gurin, J . Biol. Chem., 1951, 193, 459.lo8 S. S. Chernick, I. L. Chaikoff, E. J. Masoro, and E. Isaeff, ibid., 1950, 186, 527.lo' S. S. Chernick and I. L. Chaikoff, ibid., p.535.lo* N. Baker, I. L. Chaikoff, and A. Schusdek, ibid., 1952, 194, 435.loS S. S. Chernick, I. L. Chaikoff, and S. Abraham, ibid., 1951, 193, 793; W. C.110 G. H. Wyshak and I. L. Chaikoff, ibid., 1953, 200, 851,1952, 198, 525.Stadie, Physiol Reviews, 1954, 34, 52GREVILLE AND STEWART : FATTY ACID METABOLISM. 31 1sumably) normal, so there must be a defect beyond acetyl-coenzyme A,i.e., in the anabolic step of reaction (11). This defect is overcome byglucose injection in fasted rats,110 and by fructose, but not glucose, feedingin diabetic ones.lo8 I t apparently results frGm insLifficient supply ofglycolysable substrate in vivo ; after alloxan treatment the inhibition ofglucose utilisation is probably more severe than after fasting,lo6? 110 so thatfructose must be fed to prevent the second defect.In a soluble system fromalloxan-diabetic liver, incorporation of acetate into fatty acids is restored byaddition of glycogen or hexose phosphates; 99 the second defect in diabetes(and that after fasting, if this be the same) may, therefore, possibly be alteredpermeability of some cell component.Some evidence suggests that incorporation of acetate is dependent onglycolysis in vitro : for incorporation of acetate is proportional to theglycogen content of liver slices and also to their glycogen utilisation ; Illa andglucagon and adrenalin, known to be glycogenolytic in vitro,l12 when addedto liver slices, decrease acetate incorporation.lll* The findings with thesoluble system (previous paragraph) are in conformity with this possibility.Incorporation of l4C from acetate into fatty acids by liver slices is un-usually great when rats fasted for short periods are given a large dose ofglucose,l02? 82 and when alloxan-diabetic rats are treated with in~u1in.l~~Under the latter conditions an accelerated incorporation of 14C frompyruvate 114 into fatty acids in the slices after four days of insulin treatmentis paralleled by a transient rise in liver fat in vivo which, may, therefore, bedue to net accumulation of fat from synthesis.Unlike normal ones, theslices incorporate 14C from pyruvate 115 and acetate 113 into fatty acid muchmore extensively than into carbon dioxide, despite normal production oftotal carbon dioxide. These observations suggest increase in rate of fatsynthesis without a comparable increase in that of oxidation (cf.effect ofpyruvate on incorporation of acetate, p. 309).Fat Synthesis.-Free fatty acids may not be intermediates in fat synthesis,but direct evidence is lacking. Esterification of glycerol-a phosphate (e.g.,to give dipalmitophosphatidic acid) in a fraction from guinea-pig liver isdue to reaction between R-CO-SCoA' and R'*OH with elimination ofCOA'-SH.~~~ Fats are therefore possibly generated- by transesterification.The optimum chain length for R is 15--17 atoms, and Professor Lynenhas suggested to the Reporters that this specificity may account for thepreponderance of c16 andKetogenesis and Keto1ysis.-We define certain terms used in the text asfollows : (a) ketogenesis, formation of ketone bodies ; (b) antiketogenesis,prevention of their formation ; (c) ketoZysis, their removal ; (d) ketosis andk.b.a., ketone body accumulation in animals and in vitro respectively, whenketogenesis exceeds ketolysis.Ketogenesis.-This depends on the relative rates at which acetyl-coenzymeA is oxidised via the tricarboxylic acid cycle and converted into acetoacetate.(a) Liver.Here the k.b.a. depends mainly on the rate of ketogenesis,111 E. S. Haugaard and W. C. Stadie, ( a ) J. Bid. Chem., 1952, 199, 741; (b) 1953,1 1 2 E. W. Sutherland, " Recent Progress in Hormone Research," 1950, Vol. V, p. 441.113 J. M. Felts, I. L. Chaikoff, and M. J. Osborn, J . Bid. Chem., 1951, 193, 557.114 M. J. Osborn, J .M. Felts, and I. L. Chaikoff, ibid., 1953, 203, 173.115 M. J. Osborn, I. L. Chaikoff, and J. M. Felts, ibid., 1951, 193, 549.acids in animal lipids.200, 753312 BIOCHEMISTRY.ketolysis being small (p. 313). Slices from fed rats show aerobically aslight k.b.a., those from fasted rats a greater.116a Addition of even-C fattyacids causes considerable k.b.a. with slices from fed rats, again greater withthose from fasted animals (confirmed with labelled fatty acids l17).With perfused livers the k.b.a. is inversely proportional to the glycogencontent,l18 and with slices it is reduced by addition of g1yc0gen.l~~ Ammon-ium chloride produces ketosis in rats and k.b.a. with liver slices.116a Thisis due to suppression of the tricarboxylic acid cycle by the removal of or-oxo-glutarate as glutamate, so that 2C-fragments from fatty acids fail to beoxidised and are diverted to acetoacetate.121 Malonate increases k.b.a.inslices,122 formation of carbon dioxide from fatty acids being at the same timediminished,123 again by blockage of the cycle." 2 : PDinitrophenol(4-5 x lo-5~) increases the respiration of rat-liver slices and the ratio ofacetoacetate to P-hydroxyb~tyrate~l2~ possibly as a result of acceleratedoxidation of DPN,d.Pyruvate, as a carbohydrate metabolite, should be antiketogenic, andindeed it is in the whole animal (cf., e.g., ref. 125). However, since it israpidly oxidised to acetyl-coenzyme A l4 it is potentially ketogenic. Rat-liver particles, particularly in presence of malonate or absence of inter-mediates from the tricarboxylic acid cycle, convert pyruvate almost quan-titatively into a~etoacetate.~~ Conversion into acetoacetate also occurs inslices (see, eg., refs.116a, 124) (but not always 126), and to a slight extent inperfused and minced liver.128 Variations between different preparationsmay be related to the relative rates of (i) oxidation of pyruvate to acetyl-coenzyme A, and (ii) carbovylation of pyruvate to yield oxaloacetate whichcatalyses oxidation of acetyl-coenzyme A. Reaction (ii), observed in ratliver,l29 is likely to be more rapid in intact cells, particularly with a highcarbon dioxide tension,130 than with washed-particle preparations.131 Ifthe availability of glycogen determines the level of pyruvate, and hence thatof oxaloacetate, the antiketogenic action of glycogen and the effect of fasting(see above) may be partly explained.With rat-kidney slices, (i) there is a smallk.b.a.aerobically from butyrate and hexanoate (also with spleen andtestis),l22 (ii) labelled fatty acids (C5-C, and CI2) yield acetoacetate onlyone-tenth as fast as the'y form carbon dioxide,132 (iii) some acetoacetate isformed without added substrate,lB27 126 (iv) although net formation of aceto-(b) Extrahepatic tissues.116 N. L. Edson, Biochem. .I., 1935, 29, (a) 2082, ( b ) 2498.l 1 7 S. Weinhouse, R. H. Millington, and B. Friedman, J . Biol. Chem., 1949,181,489.11* N. Blixenkrone-Mdler, 2. physaol. Chem., 1938, 252, 117.ll9 B. G. Bobbitt and H. J. Deuel, J .Biol. Chem., 1942, 143, 1.120 V. B. Wigglesworth, Biochem. J . , 1924, 18, 1203.121 R. 0. Recknagel and V. R. Potter, J . Biol. Chem., 1951, 191, 263.122 M. Jowett and J. H. Quastel, Biochern. J . , 1935, 29, 2181.123 R. P. Geyer, M. Cunningham, and J. Pendergast, J . Biol. Chem., 1951, 188, 185.124 P. Fantl, G. J . Lincoln, and J. F. Nelson, Biochem. J., 1951, 48, 96.125 I . Shapiro, J . Biol. Chem., 1935, 108, 373.126 S. Weinhouse and R. H. Millington, ibid., 1951, 193, 1.lZ7 G. Embden and M. Oppenheimer, Biochem. Z., 1912, 45, 186.f 2 * E. Annau, 2. physiol. Chem., 1934, 224, 141.lZ9 R. K. Crane and E. G. Ball, J . Biol. Chem., 1951, 188, 819.131 M. F. Utter and H. G. Wood, Adv. Enzymology, 1951, 12, 41.132 R. P. Geyer and M. Cunningham, J .Biol. Chem., 1950, 184, 641.D. E. Green, W. F. Loomis, and V. H. Auerbach, ibid., 1948, 172, 389GREVILLE AND STEWART : FATTY ACID METABOLISM. 313acetate from acetate has not been found, isotopic acetate is readily incor-porated into added a ~ e t o a c e t a t e , ~ ~ ~ (v) fasting does not seem to increasek.b.a.,134 and (vi) malonate reduces formation of carbon dioxide fromlabelled fatty acids; 135 but we find no statement that it increases k.b.a.Even in presence of mal~nate,~f cardiac-muscle homogenates fail to formketone bodies from ~ctanoate,~f and rapidly oxidise a~etoacetate.~f* 136However, malonate causes accumulation of succinate and ct-oxoglutarate inthis tissue, unlike liver, which mainly accumulates ketone bodies, unlesshigh concentrations of dicarboxylic acids from the tricarboxylic acid cycleare present.6 We find no evidence for ketogenesis in skeletal muscle.Eviscerated animals rapidly ut ilise injectedacetoacetate.137 Kidney, 136~ 138 heart,5j diaphragm, 13* skeletal muscle, 139spleen, omentum, and brain 138 oxidise ketone bodies in vitro.That aceto-acetate is oxidised via the tricarboxylic acid cycle first appeared probablein 1943 140 and was established later.141> 136 The key reactions seem to beactivation of acetoacetate by attachment t o coenzyme A and cleavage ofthe product to acetyl-coenzyme A. Activation occurs in heart muscle,and probably skeletal muscle and kidney, by transfer of coenzyme A toacetoacetate from succinyl-coenzyme A (p. 307).The latter arises byoxidative decarboxylation of a-o~oglutarate,~~~ or from interaction ofcoenzyme A, ATP, and succinate. 143 More direct activation of acetoacetateby coenzyme A and ATP also occurs in kidney preparation^.^' The com-parative absence of acetoacetyl-coenzyme A deacylase (p. 307) in extra-hepatic tissues 57 favours these activating reactions and may be responsiblefor difficulty in detecting ketogenesis.The liver has a much greater capacity for producing ketonebodies than for utilising them. Lehninger 5e could detect no removal of aceto-acetate by rat-liver particle preparations even in presence of malate. Cohenand Stark,144 however, claimed a rapid disappearance of ketone bodies whenacetoacetate was incubated with slices of liver from various rodents, lesswith starved than with fed animals. Oxidation to carbon dioxide of theketone bodies disappearing (e.g., 140 pmoles per g.of dry tissue per hr. for a fedrat) would demand a remarkably high respiration. Recent measurementsof isotopic carbon in the respiratory carbon dioxide proved that rat-liverslices oxidise labelled acetoacetate slowly (about 12 ymoles per g. per hr.with fed,126 145 7 pmoles with fasted rats 126). Acetoacetate, when removedbut not oxidised to carbon dioxide, largely appeared as p-hydroxybutyrate.126Ketolysis .-(a) Extra hefiat i c .(b) Liver.133 G. Medes, S. Weinhouse, and N. F. Floyd, J , Biol. Chem., 1945, 157, 751.134 R. P. Geyer, E. J . Bowie, and J. C. Bates, ibid., 1953, 200, 271.135 R.P. Geyer, L. W. Matthews, and F. J. Stare, ibid., 1950, 182, 101.136 H. A. Krebs and L. V. Eggleston, Biochem. J., 1948, 42, 294.1 3 7 I. L. Chaikoff and S. Soskin, Amer. J . Physiol., 1928, 87, 58.138 R. A. Shipley, ibid., 1944, 141, 662.139 W. C. Stadie, J. A. Zapp, and F. D. W. Lukens, J . Biol. Chem., 1940, 132, 423.140 H. Wieland and C. Rosenthal, Annalen, 1943, 554, 241 ; F. L. Breusch, Science,141 J. M. Buchanan, W. Sakami, S. Gurin, and D. W. Wilson, J . Biol. Chem., 1945,1 4 2 S . Kaufman, C. Gilvarg, 0. Cori, and S. Ochoa, ibid., 1953, 203, 869; D. R.1 4 3 S. Kauf man, in Phosphorus Metabolism,” Johns Hopkins Press, Baltimore,144 P. P. Cohen and I. E. Stark, J . Biol. Clzem., 1938, 126, 97.1 4 5 R. W. Chen, D. D. Chapman, and I. L. Chaikoff, ibid., 1953, 205, 383.1943, 97, 490.159, 695.Sanadi and J . W.Littlef~ld, zbid., 1953, 201, 103.1951, Vol. I, p. 37031 4 BIOCHEMISTRY.14C from CH3*14CO*CH,*C02- appears in higher fatty acids 145 and chol-ester01.l~~j 147Whether liver oxidises acetoacetate by a route similar to that in othertissues must be considered. Liver contains but little of the enzymes whichconvert it into acetoacetyl-coenzyme A.57 Acetoacetate decompcses non-enzymically to acetone and carbon dioxide at an appreciable rate,148* 126but the acetone is probably not oxidised to carbon dioxide by liver ~1ices.l~’During the preparation of sodium acetoacetate by hydrolysis of the ethylester scme acetate is formed,147 but this could yield only a small partof the respiratory carbon dioxide attributed to a~et0acetate.l~~ WhenCH,-14CO-CH2*C02Et was added to liver slices some labelled acetate wasformed ; further addition of unlabelled acetate diminished the 14C contentof the respiratory carbon dioxide,147 but by an amount which suggests thatoxidation of acetoacetate cannot occur mainly via free acetate.Bothcarbonyl- and carboxyl-labelled acetoacetate undergo little or no random-isation of the label by rat-liver slices ; 1497 145 this might indicate that acetyl-coenzyme A is not formed, but it is not decisive in view of the many outletsfor that compound. To summarise, acetoacetate is oxidised slowly by livertissue, probably through acetyl-coenzyme A, but possibly in part throughacetate.Whole Animals.-(a) Normal. It has been widely held 150 that even in nor-mal fed animals the liver converts fatty acids largely into ketone bodies whichare oxidised to carbon dioxide and water in the extrahepatic tissues.When,however, Crandall, Ivy, and Ehni 151 analysed blocd entering and leaving theliver in dogs they did not detect production of ketone bodies by the liver unlessthe animals were fasting. There is nevertheless a sniall concentration ofketone bodies in normal circulating blocd, and Breusch,lSob making certainassumptions, calculated that the extrahepatic tissues of a fasting 75-kg. manutilise about 21 g . of ketone bodies (equivalent to about 14 g. of fat) per day.Since a normal fat intake is 100-120 g. per day, this suggests that, at themost, 15% of fat catabolism takes place via hepatic ketone-body production.The rate of fat oxidation in liverless animals can approach SOYo of that ofnormal animals, but this dces not exclude the possibility that the liver isthe principal site of fat oxidation in the intactFactors, including starvation,153 which induce ketcsisseem more usually to increase ketogenesis than to decrease ketolysis.Feed-ing with fat 1 5 1 9 1539 15* or fatty acid 155 rapidly causes ketosis, particularly(b) Abnormal.146 R. 0. Brady and S. Gurin, J . Biol. Chevn., 1951, 189, 371.14’ G. L. Curran, ibid., 1951, 191, 775.148 H. A. Krebs and L. V. Eggleston, Biochem. J., 1945, 39, 408.149 J. M. Buchanan, W. Sakami, and S. Gurin, J . Biol. Chem., 1947, 169, 411.150 (a) W.C. Stadie, Physiol. Reviews, 1945, 25, 395 ; ( b ) F. L. Breusch, Adv. Enzym-ology, 1948, 8, 343; (c) E. S. West and W. R. Todd, “ A Textbook of Biochemistry,”Macmillan, New York, 1051, p. 929; ( d ) G. G. Duncan, “ Diseases of Metabolism,”W. B. Saunders, Philadelphia, 1952, p. 221.151 L. A. Crandall, H. B. Ivy, and G. J. Ehni, Amer. J . Physiol., 1940, 131, 10.162 D. S. Goldman, I. L. Chaikoff, W. 0. Reinhardt, C . Entenman, and W. G. Dauben,J . Biol. Chem., 1950, 184, 719; R. P. Geyer, W. R. Waddell, J . Pendergast, and G. S.Yee, ibid., 1951, 190, 437.153 J. P. Peters and D. D. Van Slyke, “ Quantitative Clinical Chemistry,” Bailliere,Tindall and Cox, London, 1946, Vol. I, Part 1.lS4 L. A. Crandall, J . Biol. Chem., 1941, 138, 123.155 C. H.Beatty and E. S. West, ibid., 1951, 190, 603GREVILLE AND STEWART FATTY ACID METABOLISM. 315in previously fasted animals ; but whether ketosis persists with high-fatdiets depends on the other constituents. Ketosis produced by high-fatdiets subsides after a few days; l2O? 156 horse meat, but not casein, added tothese diets prolongs the ket0sis.l~~9 158 A nitrogen-free substance in thelipid fraction of horse muscle is effective.158 There may be a ketogenicfactor in dried liver as ~ e l l . 1 5 ~ Various extracts of anterior-pituitary glandproduce ketosis when injected,160 but the responsible constituents have notbeen unequivocally identified.Unsymmetrical Labelling of Acetoacetate.-4cetoacetate is formed bycombination of pairs of acetyl-coenzyme A molecules.If those derived byoxidation from a carboxyl-labelled fatty acid combine randomly, l3 theacetoacetate should be equally labelled in the carbonyl and the carboxylgroup (*CO/*C02H = 1). Most recorded values of *CO/*C02H, obtainedwhen rodent liver and kidney s l i c e ~ , ~ ~ ~ washed li~er-particles,~~. 8, andmitochondria1 extracts l9 act on carboxyl-labelled fatty acids, are, however,less t h m l.Sh9 8 Despite critical attention to analytical methods, quotientsvary greatly.162 The shorter the fatty acid chain, the lower is the quotient ;and C(u - ,,-labelled fatty acids give quotients up to 4.5h9 87 163 This and otherevidence my8 led to the postulate that two species of 2C-fragment ariseduring fatty acid oxidation : (1) the acetylating type [CH,*CO-1, derivedfrom the terminal CH,*CH,-, forms the acetyl group of acetoacetate ; (2) thepreferentially acetylated type [-CH,*CO-], derived from the other 2C-units,forms the -CH2*C02H. This concept may be abandoned as a result ofrecent studies with p-ketothiolase (p.307), which suggest that unsymmetricallabelling is a consequence of the mechanism of action of this enzyme(“ exchange hypothesis ”).During oxidation of a carboxyl-labelled fatty acid, there will be present(a) labelled AcCoA, (b) labelled AcAcCoA (*CO/*C02H = l), and (c) un-labelled AcAcCoA from the four atoms C ( w 4 ( w - 3 ) . I t has been sug-gested 229 z 3 9 52 that (c) will react with p-ketothiolase (HS-E) (p. 307) asfollows :giving acetyl-coenzyme A which will mix with the labelled acetyl-coenzyme A. By the right-to-left reaction, the labelled atom will then enterAc*CH,*CO*SCoA’ in the l-position.Acetoacetate formed by the fattyacid oxidation will thus become preferentially labelled in the carboxylgroup. Beinert and Stansly 32 suggest that unsymmetrical labelling arisesfrom the reactions (Enz = enzyme)Enz + A c.CH,.CO*SCoA’ m- Enz-A cCHZ.CO.S.Co,4’AcCH,.CO.S*CoA’ + HS*E @ Ac-S-E. + Ac*S*CoA’ . . (12)fCoA’.SHEnz-Ac-SCoA’ +Ac.S*CoA’ . . . . . . (13)The mechanisms are similar in principle; with both it is implicit that theAc should remain in combination with enzyme or as AcAcCoA (and not as156 C. L. Gemmill and E. G. Holmes, Biochem. J., 1935, 29, 338.157 H. P. Marks and F. G. Young, J .Endocrinol., 1939, 1, 470.158 H. B. Stewart and F. G. Young, Nature, 1952, 1’70, 956.159 H . J. Deuel, J , S. Butts, and L. Hallman, Pvoc. SOC. E x p . Biol. N. Y., 1935, 32, 897.160 For references see J . Tepperman and H. M. Tepperman, Ann. N.Y. Acad. Sci.,1951, 54, 7U7; A. L. Greenbaum and P. McLean, Biochem. J . , 1953, 54, 413.161 V. H. Cheldelin and H. Beinert, Biochini. Hiophys. A d a , 1952, 9, 661.162 D. S . Goldman, G. W. Brown, H. R. Matheson, and I. I,. Chaikoff, .I. Biol. Chem.,1952, 195. 415. 163 M. J. Coon and N. S. B. Abrahamsen, ibid., p. 805316 BIOCHEMISTRY.AcCoA or acetoacetate) long enough for significant incorporation of isotopeinto C ( l ~ of AcAcCoA. They differ in that thiolysis is by CoA’oSH in (13)and by E*SH in (12).Beinert and Stansly 32 found that when Me*14CO*S*CoA’and acetoacetate were added to a soluble system containing p-ketothiolaseand acetoacetate-succinyl-coenzyme A transferase, the acetoacetate becameunsymmetrically labelled ( *CO/*C02H < 1). They suggest exchange andcleavage reactions by which Enz-AcAc*S*CoA’ might be formed ; unsym-metrical labelling would then follow by reactions (13) or (10) (p. 307).in favour of the two-species hypothesisshould be reviewed in the light of the “ exchange hypothesis.” (i) *CO/*C02His less than 1 when liver particle preparations oxidise unlabelled octanoateand labelled acetate simultane~usly.~~~ Since the former should yieldacetoacetyl- and the latter labelled acetyl-coenzyme A, the conditions ofBeinert and Stansly’s experiment (see above) are in effect reproduced.(ii) Thelonger the fatty acid the higher is the ratio of carbon dioxide produced toacetoacetate formed,3b, 7c which may imply 5h9 that the CH,*CH,- formsacetoacetate more readily, and carbon dioxide less readily, than the other2C-units. With Lynen’s mechanism 22 of p-ketothiolase action, the CH,*CO-is the only ZC-unit which combines with the enzyme before passing throughthe acetyl-coenzyme A pool. (iii) The CH,*CH,- unit forms liver glycogenless readily than the other 2 C - ~ n i t s . l ~ ~ This may be considered in conjunc-tion with (ii) ; if the CH,*CH,- unit yields acetoacetate more readily, and isoxidised via the tricarboxylic acid cycle less readily, than the other 2C-units,then it will form liver glycogen less readily since acetoacetate is but slowlyutilised by liver (p.313).The observation l G 4 - 166 that addition of unlabelled pyruvate raises the*CO/*C02H quotient obtained with carboxyl-labelled octanoate is difficultto explain by the two-species hypothesis, since pyruvate might be expectedto yield [CH,*CO-]-type fragments.164 It is explicable by the exchangehypothesis, since unlabelled pyruvate will lower the isot ope concentration ofthe acetyl-coenzyme A pool.Chaikoff et aZ.167 found that livers from rats injected with [5-14C]- and[11-14C]-palmitate gave, in vitro, acetoacetate with *CO/*C02H 1-2-1.3,and devised a hypothesis 5h5 to explain this unexpected result.Fixation of Carbon Dioxide in Acetoacetate.-When rat-liver homogen-ates formed acetoacetate from intrinsic substrates in presence of WO,, the14C appeared in the carboxyl group.168 Addition of acetone or acetoacetatecaused no increase in carboxyl-labelling (although with CH3*14CO*CH, the14C appeared in the CH,*CO*CH,- portion of the acetoacetate) ; but withpyruvate and certain fatty acids, 14C appeared in the carboxyl group of theextra acetoacetate formed.Labelling might arise from the reaction :CH,*CO*CH,CO,H CH,*CO-CH, + CO,. Energy (AF” = 16,300 cal.)would be needed for the resynthesis ; labelling accompanying fatty acidand pyruvate breakdown might then result through utilisation of the energyderived from oxidation. Against this is the absence of 14C from acetoacetateSome evidence advanced 5h9164 D.I. Crandall and S. Gurin, J . Bid. Chew., 1949, 181, 829.185 V. Lorber, M. Cook, and J. Meyer, ibid., p. 475.1 6 6 D. I. Crandall, R. 0. Brady, and S. Gurin, ibid., p. 845.1 6 7 I. L. Chaikoff, D. S. Goldman, G. W. Brown, W. G. Dauben, and M. Gee, ibid.,1 6 8 G. W. E. Plaut and H. A. Lardy, ibid., ( a ) 1950. 186, 705; ( b ) 1951, 192, 435.1951, 190, 229GREVILLE AND STEWART : FATTY ACID METABOLISM. 317formed by oxidation of DL-p-hydroxybutyrate in presence of 14C0,, evenwith cis-aconitate as an additional source of energy; more probably, fattyacid and pyruvate yield some intermediate to which carbon dioxide is addedto form acetoacetate. Both yield acetyl-coenzyme A, which has been shownto give labelled acetoacetate in presence of *C02.19 Since the isopropylmoiety of isovalerate, following dehydrogenation adds carbon dioxide to formacetoacetate (p.321), it may possibly be that a similar 3C-group is formed,directly or indirectly, from acetyl-coenzyme A. Fixation of carbon dioxidein acetoacetate may account for the finding 169 that, when Na2l4CO, is fedto rats, 14C appears in the fatty acids of the carcass fats.Propionic Acid.-Propionate is glycogenic 170 and unlike acetate andbutyrate is not ketogenic.l7l Both in vivo 172 and in vitro 173 administrationof propionate leads to accumulation of lactate and pyruvate. Isotopicallymarked propionate fed to animals 17* or added to liver slices 173, 175 givesrise to labelled glucose units in glycogen. Three hypotheses have beenadvanced to explain this utilisation of propionate : (1) it is directly carb-oxylated in the p-position, to give succinate ; (2) it undergoes p-oxidation,forming malonic semialdehyde and malonate ; and (3) it undergoes a-oxid-ation, giving acrylate and then lactate and pyruvate.Distribution of isotope in glucose units of rat-liver glycogen derived invivo 1749 176 and in vitro 175 from propionate differs from that from lactate.For example, with CH3**CH(OH)*C02-, labelling of Ccl) equals that of &),and of C(2) equals that of Cc5), and the quotient (*Ct2) + *CpJ/(*C(L) + *Cts,) =1.5, whereas with CH3**CH2*C02- the quotient is 1.1.Thus, whilst somerandomisation of label, attributed to partial equilibration with symmetricaldicarboxylic acids of the tricarboxylic acid cycle, accompanies formation ofglucose from lactate, it is much greater when glucose is formed from pro-pionate.Again, lactate formed from *CH3-CH2-C02- by liver slices showsequal amounts of *C in positions 2 and 3.1736 These observations implya symmetrical intermediate between propionate and lactate. The distri-bution of isotopic carbon in glucose formed from propionate rules out malon-ate as intermediate 174 and therefore restricts consideration to pathways (1)and (3). The former obligatorily provides a symmetrical intermediate ;the latter would not seem t o without further assumptions (see below).Lardy177 has shown that *C02 can be fixed into propionate to formsuccinate anaerobically by extracts of acetone-dried mitochondria supple-mented with ATP.If propionate were to yield pyruvate (pathway 3),labelled succinate might arise through the sequence pyruvate __t oxalo-160 J. Schubert and W. D. Armstrong, Science, 1948, 108, 286.l i o ( a ) A. I. Ringer, J . Biol. Chem., 1912, 12, 511; ( b ) H. J . Deuel, J. S. Butts,L. F. Hallman, and C. H. Cutler, ibid., 1935, 112, 15.171 (a) M. Jowett and J. H. Quastel, Biochem. J . , 1935, 29, 2159; ( b ) E. M. MacKay,A. N. Wick, and C. P. Barnum, J . Biol. Chem., 1940, 136, 503.172 L. Blum and P. Woringer, Bull. SOC. Chim. biol., 1920, 2, 88.173 ( a ) A. Hahn and W. Haarmann, 2. Biol., 1930, 90, 231; ( b ) L. Daus, M. Meinke,and M. Calvin, J . Biol. Chem., 1952, 196, 77.174 V. Lorber, N. Lifson, W. Sakami, and H.G. Wood, ibid., 1950, 183, 531.175 W. W. Shreeve, ibid., 1952, 195, 1.176 V. Lorber, N. Lifson, H. G. Wood, W. Sakami, and W. W. Shreeve, ibid., 1960,183, 517.177 (a) H. A. Lardy and R. Peanasky, Physiol. Reviews, 1953, 33, 560; ( b ) H. A.Lardy, Proc. Nut. Acad. Sci., 1952, 38, 1003; H. A. Lardy and J. Fischer, Abstr. 123rdMeeting, Amer. Chem. SOC., 1953, p. 1 0 ~ 318 BIOCHEMISTRY.acetate + malate - fumarate __t succinate ; but this must be ex-cluded since no *C appears in malate or fumarate. It could not arisethrough the sequence : 178 4 Pyruvate + 14C0, - 2 Citrate _t. cr-Hydr-oxyglutarate + [l-14C]succinate, since C0,-carbon would not appear insuccinate. Participation of the symmetrical succinate explains (i) theisotope distribution data of the previous paragraph, (ii) the even distri-bution of 14C in trapped acetate derived from CH,*14CH,*C0,- in rat-liverslices 175 (via succinate --+ pyruvate __t acetyl-coenzyme A), and (iii) thefailure to find deuterium in acetate derived from deuterated propionate inthe rat,179 since the deuterium of the succinate will be lost on the waythrough fumarate - malate _t oxaloacetate _+ pyruvate.The pathway proposed by Green’s associates,180a propionate acryl-ate L-lactate --w D-lactate pyruvate, conforms with their con-cept 180 that L-lactate is converted into pyruvate by liver mitochondria onlyafter optical inversion by a soluble “ racemase.” (The latter depends onoxidative phosphorylation.) To reconcile their mechanism with the isotopicfindings cited above, they suggest an unusual rearrangement of the lactate ion,involving a symmetrical intermediate, under the action of the “ racemase.”Their main evidence for the a-oxidation pathway is: (a) Carbon fromlabelled propionate appeared in lactate and pyruvate.lsl However, theinterconvertability of succinate and pyruvate makes this equally consistentwith pathway (1).(b) To obtain propionate oxidation by cyclophorasepreparations, a soluble liver-fraction had to be added, the function of whichwas ascribed to its “ racemase ” activity 1806 (similar activation has, how-ever, been obtained with excess of succinate ls2). If “ racemase ” is neces-sary, the propionate oxidation path must pass through lactate. However,there is no evidence that the factor in the soluble fraction is “ racemase.”The factor is possibly part of the system for propionate-succinate conversion ;it may well have been washed out of the cyclophorase particles but retainedin Lardy’s acetone-dried mitochondria.It is noteworthy that propionate-succinat e conversion is greatly reduced in Lardy’s preparations when madefrom biotin-deficient rats, but is restored by addition of “ protein fractionsfrom normal animals.” 177aWhilst there is as yet no need to recognise the a-oxidation pathway forpropionate in animals, it seems that in a micro-organism, Clostridiumpropionicum, this path may be traversed in reverse.lS3 Thus acrylate yieldspropionate, and lactate is converted into propionate without shift of isotopiccarbon from the cr- to the p-position 184 and without carbon dioxide fix-ation.185 In other bacteria, however, carbon dioxide is fixed into propionateto form succinate,186 and acrylate is not metab01ised.l~~1 7 8 C. Martius, in “ Symposium sur le Cycle Tricarboxylique,” IInd Int.Congr.1 7 0 K. Bloch and D. Rittenberg, J . Biol. Chem., 1944, 155, 243.1 8 0 F. M. Huennekens, H. R. Mahler, and J. Nordmann, Arch.Biochem., 1951,30, (a)66,1 8 1 H. R. Mahler and F. M. Huennekens, Biochim. Biophys. Acta, 1953,11,575.182 K. Lang and K. H. Bassler, Biochem. Z., 1953, 324, 401.183 B. P. Cardon and H. A. Barker, Arch. Biochem., 1947, 12, 165.184 F. W. Leaver, Fed. Proc., 1953, 12, 471.185 A. T. Johns, J . Gen. Microbiol,, 1952, 6, 123.186 ( a ) E.A. Delwiche, E. F. Phares, and S. F. Carson, Fed. Proc., 1953, 12, 194;( b ) H. Larsen, J . Bid. Chew., 1951, 193, 167; S. Barban and S. Ajl, ibid., 1951, 199, 63.187 H. A. Barker and F. Lipmann, Arch. Biochem., 1944, 4, 361.Biochem., Sedes, Paris, 1952, p. 28.( b ) 77GREVILLE AND STEWART FATTY ACID METABOLISM. 319Studies with cell-free bacterial preparations have thrown light on themechanism of propionate-succinate interconversion. Whiteley lg8 hasfound that, with extracts of Micrococcus Zactilyticus depleted of coenzyme Aand ATP, addition of these substances in “ catalytic ” amounts evokesdecarboxylation of succinate.Succinyl-CoA __+ CO, + Propionyl-CoAHe gives evidence for the mechanism :3-Propionate 2 4-. Succinateand for priming of the system by initial generation of succinyl-coenzyme ‘4from succinate, ATP, and coenzyme A.With Propionibncterium pentos-aceum extracts, Delwiche, Phares, and Carson 18& found that coenzyme Aand ATP are needed for succinate decarboxylation, but apparently onlycoenzyme A is needed for carboxylation of propionate. C0,-carbon wasincorporated into excess of unlabelled succinate much more slowly than waspropionate-carbon. They infer that a propionate derivative combines withsome one-C derivative (possibly of coenzyme A lg9), obtained from succinate,in preference to carbon dioxide, At present, however, the evidence does notseem to demand any such derivative. If compounds A and B react underthe influence of enzyme E to form AB, so that, for instance, E + A + BA-E-B + E-AB +, E + AB, and if A leaves and returns to E morerapidly than does B, then unlabelled AB takes up from solution labelled Amore rapidly than labelled B (cf.ref. 131).Other Odd-carbon Fatty Acids.-These are metabolised,21- l g 0 9 lgl and toa small extent deposited in the fat depots,l92 with some 9 : 10-desat~rati0n.l~~Odd-C acids (C5-C,,) are ketogenic both in vitro 1 7 1 a 9 lg4 and in ~ l i v 0 , l ~ l ~though less so than even-C acids; addition of malonate greatly increases theyield of acetoacetate from liver slices metabolising odd-C acids (C,-C,) .123Odd-C acids (C3-Cll) , unlike even-C acids, are glycogenic as well.170‘C7--CI7 acids are as rapidly oxidised as even-C acids by liver particulatepreparations, but the yield of acetoacetate is smaller.7c Kidney cyclo-phorase preparations, oxidising odd-C acids, consumed oxygen in amountindicating the final formation of carbon dioxide, water, and propionate.lOaFormation of propionate (and, probably, traces of acetate) from n-valerateunder these conditions was established by counter-current distribution. lg5Since accumulation of acetoacet ate, l7lb> 7c enhanced by malonate, 123 impliesp-oxidation with liberation of acetyl-coenzyme A, odd-C acids are probablyshortened by p-oxidation two carbons at a time until a 3C-unit remainswhich behaves as propionate (see above). The subsequent formation ofa tricarboxylic acid cycle intermediate which catalyses oxidation of acetyl-188 H. R. Whiteley, Pvoc.Nut. Acad. Sci., 1953, 39, 772, 779.I8O H. G. Wood and F. W. Leaver, Biochim. Biophys. -4cta. 1953, 12, 207.lD1 ( a ) W. Keil, H. Appel, and G. Berger, 2. physiol. Chewz., 1939, 257, I ; ( b ) H.Appel, G. Berger, H. Bohm, W. Keil, and G. Schiller, ibid., 1940, 266, 158; (c)’R. Emm-rich and E. Nebe, ibid., p. 174.lS2 K. Thomas and G. Weitzel, in “ FIAT Review of German Science, 1939-1946,’’Biochemistry, Part I, Office of Military Government for Germany Field InformationAgencies, Technical, Wiesbaden, 1947, p. 1.H. Appel, H. Bohm, W. Keil, and G. Schiller, 2. physiol. CJzem., 1047, 282, 220.lQ4 R. P. Geyer, M. Cunningham, and J. Pendergast, J . Biol. Chem., 1950, 185, 461.lg5 JV. A. Atchley, ibid., 1948, 176, 123.F. Knoop, Beitr. Chern. Physiol.Path., 190.5, 6, 150320 BIOCHEMISTRY.coenzyme A explains the low yield of ketone bodies. Since the ultimatefragment contains three rather than two carbon atoms, the low *CO/*C02Hquotient in the “ acetoacetate ” analysed after n-valerate catabolism 194,161 isnot explained by current hypotheses (p. 315). If CH,CH2*CO*CH2**C02Hwere to accumulate, however, it would yield a low *CO/*C02H quotient by theanalytical method used. Similar considerations apply to higher odd-C acids.Shorter Branched Fatty Acids.-Recent work indicates that these undergop-oxidation, and gives evidence neither for dealkylation nor for a- or y-oxid-ation a t one time considered as pos~ib1e.l~~isoButyric acid arises from iso-acids with an odd number of carbon atomsin the straight chain, and from valine by oxidative decarboxylation of itsketo-analogue.lg7 Atchley lS5 showed by counter-current methods thatkidney “ cyclophorase ” preparations (which unsupplemented failed tooxidise propionate) oxidised 4-methylpentanoate to isobutyrate. Alsoisobutyrate gave propionate, probably by p-oxidation of one methyl group tothe aldehyde level, followed by decarboxylation and completion of theoxidation. This is supported by the observation that [2-14C]valine yields14C02 in kidney homogenates, whilst 14C from [4 : 4’-14C,]valine appears inlactate, equally distributed between the methyl and the carboxyl group, inisobutyrate and propionate, but does not appear in carbon dioxide.lg8Isotope distribution in the glucose units of glycogen from rats given C(3)-labelled valine was almost identical with that after administration ofCH3-*CH2*C02-.lS9 Hence odd-C fatty iso-acids are converted by poxidationinto isobutyrate, and then by P-oxidation and decarboxylation into propionate.a-Methylbutyric acid also appears to be attacked by p-oxidation.Administration of a-methyl-7-phenylbutyrate to dogs leads to excretion ofphenylacetate; 200 and Carter 201 believed that p-oxidation occurs along thelonger chain, resulting in a 3C-fragment and a straight-chain fatty acid. Thisis supported by liver-slice experiments 163 with a-methyl-[~arboxy-~~C]- and-[jd4C]-butyrate ; the carboxyl group contributed virtually no carbon to theacetoacetate formed, while the [3-14C]-compound yielded acetoacetate with*CO/*C02H about 1.These findings suggest that C(l), Ct2),. and a methylgroup separate as one unit which is metabolised without direct formationof acetyl-coenzyme A, while C(3) and Cc4) form acetyl-coenzyme A and henceacetoacetate. Since isoleucine, which is metabolised to a-methylbutyrate, isslightly glycogenic,202 the 3C-fragment probably forms pyruvate, possiblythrough propionate.isovaleric acid is apparently an intermediate in leucine catab01ism.l~~Leucine and isovalerate are ketogenic in vivo 202, *03 and in vitro.llGb> 204196 K. Lang and F. Adickes, 2. physiol. Chem., 1940, 263, 227.1137 S. J. Bach, “ The Metabolism of Protein Constituents in the Mammalian Body,”198 D. Kinnory and D. M. Greenberg, Fed. Proc., 1953, 12, 230.19s E.A. Peterson, W. S. Fones, and J. White, Arch. Biochem. Biophys., 1952, 36,201 H. E. Carter, Biol. Sylnp,, 1941, 5, 47.203 J. S. Butts, H. Blunden, and M. S. Dunn, J . BioZ. Chem., 1937, 120, 289; L. C.203 J. Baer and L. Blum, Arch. exp. Path. Pharmak., 1906, 55, 89; 58, 92; A. N.204 G. Embden, H. Salomon, and F. Schmidt, Beitr. Chem. Physiol. Path., 1906, 8,Oxford, Univ. Press, 1952, Chap. IV.323. H. D. Kay and H. S. Raper, Biochem. J . , 1924, 18, 153.Terriere and J. S. Butts, ibid., 1951, 190, 1.Wick, J . Biol. Chem., 1941, 141, 897.129; M. J. Coon and S. Gurin, J . Biol. Chem., 1949, 180, 1159GREVILLE AND STEWART : FATTY ACID METABOLISM. 321In liver slices, isovalerate undergoes p-oxidation yielding (a) a 2C-frag-ment 205 from C(l) and C(2) which can form acetoacetate 206 or, presumably,be oxidised through the tricarboxylic acid cycle, and (b) an isopropylmoiety 207 which by fixation of carbon dioxide yields acetoacetate,206, 16gbC(4) and C(4t) (the Me-carbon atoms) giving rise to the a- and the y-carbonatom of acetoacetate and Cts) to its carbonyl group.Leucine seems to be non-glycogenic.2OS9 202 The above mechanism conforms with this, unless acetonecan yield carbohydrate,209 since there is no proved route by which 2C-unitsat the level of oxidation of acetic acid can give a net yield of glycogen.p-Ethylbutyric acid is also ketogenic, but is not analogous to the methylderivative since it yields acetone and not ethyl methyl ketone.lS6Higher Branched-chain and Dicarboxylic Acids.-There has been muchwork of a more physiological nature on these because of their importance insynthetic fat manufacture.In general the acid has been fed as ester orglyceride, and metabolic products isolated from the urine. Interpretationof results is rendered difficult by uncertainty regarding the degree of absorp-tion, ease of penetration to sites of metabolic activity, extent of storage indepots and liver, and existence of excretion routes other than urine. Thefinding2lO that the amount of o-oxidation can depend on the glycogenreserves indicates a further uncertainty. With these reservations the follow-ing generalisations appear to be consistent with the literature examined.(1) 2-, 3-, and 4-Methyl fatty acids are well ~ti1ised.l~~- 2019 211y 212 Whenthere is a methyl group on an even-numbered carbon atom of the chainp-oxidation probably occurs, with separation of a 3C-fragment. The fateof acids with a methyl group on an odd-numbered carbon atom is less clear,except in the case of isovalerate (see above).Acids with alkyl' brancheslarger than methyl are less well utilised. When the main chain is fromC,-C,, branched-chain acids are largely excreted in the urine unchanged ;when the main chain is from C, to CIz the branch (Et, Pr, or Bu) preventscomplete p-oxidation, although the chain may be shortened by one or two2C-units before 213 With still longer 2-alkyl fatty acids(C14 and C18) utilisation appears to be much better, less than 10% of theabsorbed acid appearing in the urine as unchanged or w-oxidised material;p-oxidation possibly occurs with separation of one short- and one long-chain normal fatty acid.212(2) Of the unbranched dicarboxylic acids, succinic and glutaric appear tobe well ~ t i l i s e d , ~ ~ ~ and adipic, pimelic, suberic, azelaic, and sebacic to beexcreted unchanged; the higher acids are sometimes shortened by one or206 M. J.Coon, ibid., 1950, 187, 71. 205 K. Bloch, J . B i d . Chem., 1944, 155, 255.207 I. Zabin and K. Bloch, Fed. PYOC.. 1949, 8, 267.208 0. Simon, 2. physiol. Chem., 1902, 35, 315; J. T. Halsey, Amer. J . Physiol.,209 H. G. Wood, in '' Isotopes in Biochemistry " (Ciba Foundation Conference),210 P. E. Verkade, J. van der Lee, and M. Elzas, Biochim. Biofihys. Acta, 1948, 2, 38.211 W.Keil, 2. physiol. Chem., 1942, 274, 175. 21* G. Weitzel, ibid., 1951, 287, 254.213 W. Keil, ibid., 1942, 276, 26; 1947, 283, 137.214 R. Emmrich, ibid., 1939, 261, 61; R. Emmrich, P. Neumann, and I. Emmrich-Glaser, ibid., 1941, 267, 228; K. Bernhard, ibid., 269, 135; K. Thomas, G. Weitzel, andP. Neumann, ibid., 1947, 282, 192; H. Bodur, ibid., p. 206; G. Weitzel, H. Queckenstedt,W. Grellmann, and H. Lautner, ibid., 1950, 385, 58; K. Bernhard and H. Lincke, Heh.Chim. Acta, 1946, 29, 1457.1904, 10, 229.Churchill, London, 1951, p. 227.*Is K. Thomas and G. Weitzel, Deut. med. Woclz., 1946, 71, 18.REP.-VOL. L 322 BIOCHEMISTRY.two 2C-unitsJ presumably by p-oxidation.lg2, 216 Blocking one carboxylgroup by ester, amide, or substituted amide formation prevents appearancein the urine of the administered acid, but its fate is unknown.217(3) Acids obtained by alkylation of malonic, succinic, glutaric, and adipicacids are not extensively utilised, and if the alkyl substituent is less than sixcarbon atoms in length they appear in the urine in large quantities. Withlonger alkyl substituents, excretion of the acids in the urine diminishes oreven ceases, and they are probably ~ t i l i s e d .~ ~ ~G. D. G.H. B. S.5. CONSTITUENTS OF THE MARINE ALGALAlthough occasional reference has been made in these Reports to con-stituents of marine algae, no collective review has appeared previocsly.This summary attempts, therefore, to emphasise modern work on the mainconstituents of the brown, red, and green algae.As it has not been pcssibleto consult many Japanese journals, and as work carried out in Japan duringthe last ten years is only now appearing in Chemical Abstracts, this Reportcannot be regarded as complete. It is hoped, however, that T. Mori willbring the Japanese literature up to date in his forthcoming review on sea-weed po1ysaccharides.lCarbohydrates of Brown Marine AIgae (Phaeophyceae) .-In recent yearsconsiderable work has been carried out in Canada,2 Japan,3 and Britain4on factors affecting the chemical composition of the brown algz. Thechemical composition depends on species, season of the year, habitat, depthat which the alga grows, and stage of de~elopment.~ Concentration gradientsare found in both the Fucaceze and the Laminariacez.6 Furthermore, acorrelation exists between the chemical composition of the algae and thecomposition of the sea-water in which theygrow.7 The work 4, 6l has requiredmethods of analysis for mannitol, alginic acid, laminarin, and combinedfucose,S and improved methods for alginic acid and combined L-fuccse.loThis is present in solution in the cell sap and increases fromabout 5% of dry Laminariacez fronds in spring to over 35% in late ~ u m m e r , ~and shows considerable variation with depth of growth and also along thefrond of the same plant.6 Laboratory-scale isolations have been workedout aiming at ultimate large-scale production.ll These comprise solvent21G R.Emmrich and I. Emmrich-Glaser, 2. physiol.Chem., 1940, 266, 183 ; K. Bern-hard, Helv. Chim. A d a , 1941, 24, 1412.217 B. Flaschentrager, 2. physiol. Chem., 1926, 159, 297; B. Flaschentrager andK. Bernhard, ibid., 1936, 240, 19; K. Bernhard, ibid., 1937, 246, 133; R. Kuhn andI. Low, ibid., 1939, 259, 182. 1 T. Mori, Adv. Cnrbohydvate Chem., 1954, 8, in the press.2 M. G. Macpherson and E. G. Young, Canad. J . Bot., 1952, 30, 67. ' N. Suzuki, Bull. Fac. Fish. (Hokkaido Univ. Japan), 1953, 3, 68.4 W. A. P. Black, Nature, 1948, 161, 174; J . SOC. Chem. Ind.. 1948, 67, 165, 355;1949, 68, 183; 1950, 69, 161; J . Marine Biol. Assoc., 1950, 29, 45.B. L. Moss, Ann. Bot., 1950, 14, 395.W. A. P. Black, J . Marine Biol. Assoc., 1954, 33, 49.7 W. A. P. Black and E. T. Dewar, ibid., 1949, 27, 673.8 3%.C. Cameron, A. G. Ross, and E. G. V. Percival, J . Soc. Chem. Id., 1045, 67,0 E. G. V. Percival and A. G. Ross, ibid., p. 420.10 W. A. P. Black, W. J. Cornhill, E. T. Dewar, E. G. V. Percival, and A. G. Ross,l 1 W. A. P. Black, E. T. Dewar, and F. N. Woodward, J . Appl. Chem., 1951, 1, 414.MautizitoZ.161.ibid., 1950, 69, 317BLACK : CONSTITUENTS OF THE IvfAKINE ALGE. 323extraction of dried algz and complete evaporation of dilute acid extracts offresh or dried algze, followed by isolation of mannitol by (a) solvent-extraction, (b) precipitation as the water-insoluble triisopropylidene ortriethylidene derivative, or (c) the use of ion-exchange resins. Recentchromatographic work on extracts of F. vesiculosus has shown the presence,in small amounts, of D-mannitol l-acetate, l-(p-D-glucopyranoside), and1 : 6-di-( ~-~-glucopyranoside).l2has shown that there are two periods of growthin the sea. The period of slow growth coincides with deficiency of nitrateand phosphate in our waters 7 when laminarin accumulates to form as muchas 36% of the dry frond of L. doustoni. Laminarin 1 4 9 l5 appears to be areserve carbohydrate of the brown algae; it is, however, absent from thestipe of the Laminariaceae a t all times of the year and from the activelygrowing section of the frond proximal to the stipe, but makes up 32% ofthe dry matter of distal sections.6 It exists in two forms; L. doustonifrond and, to a lesser extent, L. saccharina frond, give the so-called insolublelaniinarin (insoluble in cold water but readily soluble in hot water), whileL.digitata frond gives the form soluble in cold water. Both modificationshave recently been studied,l6* 1 7 but no fundamental chemical differenceshave been observed between them. The general structure is a chain ofabout twenty 1 : 3-linked p-D-glucopyranose units. During the present year,however, evidence for the presence of branch linkages in laminarin has beenprovided l8 by the isolation, after column-chromatography, of small quan-tities of gentiobiose and pp-trehalose from the partial hydrolysis of insolublelaminarin. The breakdown of laminarin with lime-water also favours abranched structure ; l9 if laminarin is compcsed exclusively of an unbranchedchain of 1 : 3-p-linked glucose units it would be completely brokendown from end to end whereas lime-water treatment resulted in only 5076cleavage." Laminaritol " has been prepared by reducing laminarin with sodiumborohydride; 2o recent X-ray studies have shown that the two forms oflaminarin, when prepared under identical conditions, give similar diagrams 21which are, however, different from that of the paramylon of EugZena.22Methods for isolating and purifying laminarin from brown marine algaehave been described 23 and the quantitative production of D-glucose fromlaminarin has recently been ~tudied.2~ From an autoclaved solution of thepolysaccharide (18% w/w) in O-O5~-hydrochloric acid (at 135" for one hour)D-glUCOSe monohydrate is obtained crystalline by a process similar to itscommercial production from starch.Laminarin.Parkel2 B. Lindberg, Acta Chem. Scund., 1953, 7, 1119.l3 M. Parke, J . Marine Bid. Assoc., 1948, 27, 651.I4 H. N. Rydon, Ann. Reports, 1950, 41, 247; 1951, 48, 237.l7 E. G. V. Percival and A. G. Ross, J., 1951, 720.l 8 S. Peat, W. J . Whelan, and H. G. Lawley, Biochenz. J . , 1953, 54, xxxiii.Is W. M. Corbett, J. Kenner, and G. N. Richards, Chern. and I d . , 1953, 462.2o M. Abdel-Akher, J. K. Hamilton, and F. Smith, J . Amer. Chem. Soc., 1951, 73,22 D. R. Kreger and B. J. D. Meeuse, Biochiwz. Biophys. A d a , 1952, 9, 699.23 w. A. P. Black, W. J. Cornhill, E. T. Dewar, and F. N. Woodward, J . A p p l .24 W. A. P. Black, E. T. Dewar, and F. N. Il'oodward, J . Sci. Food Agvic., 1953.4, 5 8 .E. J. Bourne, ibid., 1952, 49, 242.J. J. Connell, E. L. Hirst, and E. G. V. Percival, J . , 1950, 3494.4691. 21 E. Nicolai and R. D. Preston, unpublished work.Chem., 1951, 1, 505324 BIOCHEMISTRY.Fucoidirt. Brief mention has been made in a previous Report l4 offucoidin. This polysaccharide sulphate is believed to occur in the inter-cellular mucilage of the brown algae and to undergo marked seasonal fluctu-ation which varies with the depth of immersion of the alga.25 Thus, in moretidally exposed algz like Pelvetia canaliculata it makes up over 20% of thedry matter. Its function, in view of its hygroscopic nature, may be toprevent desiccation on prolonged exposure. In the permanently submergedLaminariaceae, on the other hand, it makes up only about 5%. The isolationand purification of fucoidin have been studied by (the late) E.G. V. Percivaland A. G. Ross,26 who consider that its repeating unit is derived from acalcium fucose monosulphate (C6H90a,S03Ca,-,.5),. Hydrolysis of methylatedfucoidin (F. vesicuZosus) gave L-fucose, 3-O-methyl-~-fucose, and 2 : 3-di-0-methyl-L-fucose, roughly in the proportions 1 : 3 : l.27 The predominantradical in fucoidin was, therefore, believed to be a 1 : 2-a-fucopyranose unitsulphated on C(41. Two theories were advanced to account for the free fucoseand the 2 : 3-di-O-methyl-~-fucose residues in methylated fucoidin : (1) somefucose residues might carry two sulphate groups, whereas others (linked 1 : 4)are unsubstitituted, or (2) the free fucose might originate from branchingpoints at and the dimethyl derivative from terminal groups having freehydroxyl groups on C+,) and C(3).Larger-scale isolations of fucoidin,28 involving treatment of the algaewith hydrochloric acid a t 70" for one hour at pH 2.0-2-5, fractional pre-cipitation with alcohol, and final purification with formaldehyde, have beendevised.Laboratory-scale preparations of L-fucose from dried milled algaehave been studied 29 through the following stages : (1) acid hydrolysis;(2) formation of fucose phenylhydrazone; and (3) decomposition of thephenylhydrazone. Isolation of L-fucose from fucoidin z9 involves heatinga 16% (w/w) solution of the polysaccharide in 0.25~-hydrochloric acid a t135" for 2 hours, treatment with ion-exchange resins, purification withethanol and charcoal, and direct crystallisation of the fucose from ethanol.Fucoidin from Pelvetia canaliculata gave crystalline fucose in 56.6% yieldand of 95.10/ urity.From the" 'seed mucilage '' of Ascophyllum nodosum a polysaccharideresembling fucoidin has recently been isolated30 as the salt of a poly-saccharide sulphuric ester consisting of fucose and galactose units in theratio of about 8 : 1, with a sulphate hexose ratio of 1 : 1.AZginic acid.Alginic acid, which with cellulose makes up the cell wallof brown algae, was recently reviewed in an investigation to evaluate thecommon brown algae as a source of alginate.31 Viscosities of 0.25% sodiumalginate in O-lN-sodium chloride at 25" were determined for Pelvetia canal;-culata, F.spiralis, F. vesiculosus, F. serratus, Ascophyllum nodosum, Lami-naria cloustoni, L. saccharina, and L. digitata, Factors affecting the gradeof the alginic acid were also studied. Recent work has confirmed the mainstructural feature of the molecule as repeating 1 : Plinked p-D-mannuronic25 W. A. P. Black, unpublished work.26 E. G. V. Percival and A. G. Ross, J . , 1950, 717.27 J . Conchie and E. G. V. Percival, J., 1950, 827.28 W. A. P, Black, E. T. Dewar, and F. N. Woodward, J. Sci. Food Agric., 1952,3, 122.PB W. A. P. Black, W. J . Cornhill, E. T. Dewar, and F. N. Woodward, ibid., 1953,4,85.*O T. Dillon, K. Kristensen, and C. 0 hEochdha, Proc. Roy. I r i s h Acad., 1953,55, B, 189.31 W. A. P. Black, W. J .Cornhill, and E. T. Dewar, J. Sci. Food Agrzc., 1952, 3,542BLACK: CONSTITUENTS OF THE MARINE ALGE. 325acid radicals; the chain length of the alginic acid used was aboutThe methylated alginic acid was hydrolysed (by formic acid), the productswere esterified by methanol, and the resulting esters were reduced to thecorresponding methyl mannosides by lithium aluminium hydride. Themethylated mannoses, formed after aqueous-acid hydrolysis, were separatedchromatographically ; 2 : 3-di-O-methylmannose was found to be the maincomponent with traces of 2 : 3 : 4-tri-O-methyl- monomethyl-mannose, anddimethyl-glucose. It is not known whether the glucose forms part of thestructure or is present as an impurity.Mention may be made of Japanese chemical studies on sodium alginateas a blood-plasma substitute ; 333 34 relations between the degree of pcly-merisation, viscosity, concentration, and colloidal osmotic pressure in 0.9%saline solution, and the permeability of blood vessel walls, have been deter-mined.The mutual coagulation of sodium alginate with protein and itsagglomerating action on red cells have been studied, while a new methodhas been worked out for its determination in serum and urine.33 In America,alginic acid sulphate and its salts have been tested as blood anti-~oagulants.~~Cellulose isolated from various species of marine alge has beenshown to be essentially the same as cotton c e l l ~ l o s e . ~ ~ Hydrolysis with 72%sulphuric acid gave only D-glucose, and cellobiose octa-acetate has beenprepared by acetolysis, indicating the presence of 1 : 4-p-linkages.X-Raydiagrams of algal cellulose have the characteristic pattern of normalcellul0se.~7In brown marine algae, a marked seasonal variation in the cellulosecontent is found in the common Laminariacez and Fucaceae 38 which maycontain, eg., less than 1% of cellulose (in Ascofhyllum nodosum) to 10%[in L. cloustoni stipe (dry basis)].Cellulose.Kylin has reviewed the biochemistry of the P h z o p h y c e ~ . ~ ~Carbohydrates of Red Marine Algae (Rhodophyceae) .-Although mentionhas frequently been made in these Reports of constituents of the Rhodo-phycez, especially agar 403 419 42 and ~arragheenin,~~~ 443 4s the chemistry of thered marine algae has not been so thoroughly investigated as that of the brownalgae.Sufficient is known, however, to show that little similarity existsbetween the two groups. Ross46 recently analysed 26 species of red algaefor ash, total sulphate, nitrogen, carbon tetrachloride- and ethanol-solublematerial, uronic acid, cellulose, and total reducing sugars after hydrolysis ;the various sugars obtained were identified on the paper chromatogram. Inthe majority of the species, galactose was the predominant sugar with smallamounts of glucose, xylose, mannose, and fucose ; in Rhodymenia palmataand Rhodoclaorton joridulum the main sugar was xylose, while Dilsea edulishad a comparatively high glucose content. Galactose in the red algE is32 S. K. Chanda, E. L. Hirst, E. G. V. Percival, and A.G. Ross, J., 1952, 1833.33 K . Inokuchi, Mem. Fac. Sci. Kyushu Urtiv., 1950, Ser. C, Chem. 1, 109.34 H. Matsubayashi, Igaku Kenkyuu, 1953, 23, 187.35 H. E. Alburn, U.S.P. 2,612,49811952 ; 2,638,46911953.36 E. G. V. Percival and A. G. Ross, J., 1949, 3041.38 W. A. P. Black, J. Marine Biol. Assoc., 1950, 29, 379.39 H. Kylin, Kgl. fysiogr. Sallsk. Lund Forh., 1944, 14, 226.O0 E. L. Hirst and S. Peat, Ann. Reports, 1936, 33, 251.41 S. Peat, ibid., 1939, 36, 269.O3 F. W. Norris, ibid., 1940, 37, 425.45 H. N. Rydon, ibid., 1950,47,247.37 Idem, Nature, 1948, 162, 895.O2 Idem, ibid., 1941, 38, 153.44 J. K . N . Jones, ibid., 1946, 43, 196.4 6 A. G. Ross, J . Sci. Food Agric., 1953, 4, 333326 BIOCHEMISTRY.present chiefly as a galactan or galactan sulphuric ester, such as agar orcarragheenin; xylose in Rhodymenin palrnata is present as a xylan, whilemost of the glucose obtained on mild hydrolysis is considered to be derivedfrom Floridean starch.These constituents will be discussed below.D-Mannitol, the well-known hexitol ofthe brown seaweeds, has not been detected in the red algze, but dulcitol(galactitol) and sorbitol (D-glUCitOl) have been isolated from Bostrychins c o ~ p i o i d e s , ~ ~ while dulcitol has been shown to be present in Iridaea lami-n a ~ i o i d e s . ~ ~ Nothing is known of the quantities present, or whether theyundergo seasonal variation ; their presence in species common to GreatBritain, such as Gigartina stellata or Rhodymenia Palmata, has not beenproved.The glycoside “ floridoside ” was dissovered in R.palmata by K ~ l i n , ~ ~who concluded it was trehalose; this was later disproved.50 R. palmata isreported 51 to contain 15% of floridoside, and its presence has been demon-strated in 19 species of red Colin 53 considered this substance to beglycerol 2-( a-~-galactoside). Polysiphonia fastigiata and P. fructiculosahave been shown to contain sodium L-glycerate .-~-mannoside. 54Granular material which gives a colour with iodinehas been observed histologically in various red a l p (for references to 1937and 1945 respectively, see Kylin 55 and Fritsch 56). The iodine colour variesfrom deep violet to brown. In the isolation of Floridean starch from Dilseae d ~ l i s , ~ ~ the weed is first extracted with cold dilute hydrochloric acid toremove the galactan sulphuric ester, and the Floridean starch is then dis-solved with boiling water and precipitated by alcohol.The purified pro-duct, [.]: +156” (in water), gave D-glucose (96%) on hydrolysis and resistedattack by crystalline P-amylase. Oxidation with periodate showed that itis structurally different from normal starches and glycogens in that it con-tains a large proportion of 1 : 3- as well as 1 : 4linked units. During thepast year, Floridean starch from Dilsea edulis has been further investig-ated; 58 extracted as before 57 and treated with ion-exchange resins, it couldnot, however, be freed completely from galactan sulphate. The specificrotation (+166” in water) indicated a predominance of rx-links, and hydro-lysis with a wheat @-amylase extract gave a 50% yield of maltose (cf.ref. 58).The polysaccharide was acetylated and methylated, but the methoxylcontent could not be raised above 28.2%. Fractionation of the hydrolysedether on a hydrocellulose column gave 2 : 3 : 6-tri-O-methyl- (42%) and2 : 3 : 4 : 6-tetra-O-methyl-~-glucose (3.3%), thereby proving that about50% of the molecule consists of 1 : 4linked a-D-glUCOpyranO.93 units.Hexitols and simple glycosides.Floridean starch.4 7 P. Hass and T. G. Hill, Biochem. .J., 1931, 25, 1470; 1932, 28, 987.4 8 W. Z. Hassid, Plant Physiol., 1933, 8, 480.49 H. Kylin, 2. physiol. Chem., 1915, 94, 337.5O H. Colin and E. GuCguen, Compt. rend., 1930, 190, 653; 191, 163.51 H.Kylin, 2. physiol. Chem., 1915, 101, 236.52 H. Colin and E. GuCguen, Compt. rend., 1933, 197, 1688.53 H. Colin, Bull. Soc. chim., 1937, 4, 277.54 H. Colin and J. Augier, Compt. rend., 1939, 208, 1450.55 H. Kylin, Linsbauer “ Handbuch der Yflanzenanat.,” Vol. VI, 2B, Borntracger,56 F. E. Fritsch, “ The Structure and Reproduction of the Alga3,” Cambridge Univ.5 7 V. C. Barry, T. G. Halsall, E. L. Hirst, and J. K. N. Jones, J., 1949, 1468.68 P. O’Colla, Proc. Roy. I r i s h Acad., 1953, 55, B, 321.Berlin, 1937.Press, 1945, Vol. 11, p. 409BLACK: CONSTITUENTS OF THE MARINE ALGB. 327Agar. The production and uses of this important polysaccharide havebeen extensively reviewed in recent years.59160361 Early work on theconstitution of agar is amply covered by T ~ e n g , ~ ~ while elucidation of itsstructure by methylation is described in a number of excellent reviews.62* 633 64The recent article by Araki 64 summarises the large amount of work done bythe Japanese in this field.When agar was last reviewed in these Reports,42the constitution was represented by a chain of nine 1 : 3-[3 linked D-galacto-pyranose units, terminated by an L-galactopyranose 6-sulphate residuelinked through C(4). During methylation, the terminal sulphate residue wasbelieved to be split off with the formation of a 3 : 6-anhydro-ring, and thistheory was put forward t o account for the presence of 3 : 6-anhydro-~-galactose residues among the hydrolysis products of methylated agar.65This view on the structure of agar has been contested 6 6 7 6 7 on the groundthat the sulphur content of natural agar is too low to account for the yieldsof 3 : 6-anhydro-~-galactose derivatives isolated, although Percival 63admitted that the 3 : 6-anhydro-ring could have been formed by cleavageof a sulphate group at some earlier stage in the elaboration of the poly-saccharide.Little work of a structural nature has been done on agar during the pastten years.A disaccharide, agarobiose, has been obtained by partial hydro-lysis, and methanolysis yielded methyl a-D-galactopyranoside and 3 : 6-anhydro-L-galactose dimethyl acetal.68 Agarobiose was shown 69 to be4-O-[ [3-D-galactopyranosyl]-3 : 6-anhydro-~-galactose by methylation andhydrolysis, thus confirming the view 6 5 1 70 that the 3 : 6-anhydro-~-galactoseis attached t o the chain through C(4).Carragheenin, first isolated by Schmidt ,71 is the driedaqueous extract obtained from Clzondrus crisfius or Gigartinn stellata, andthese two species, either individually or together, are known as “ carragheen ”or “ Irish Moss.” The production and uses of carragheenin (“ BritishAgar ”) are similar to those of agar, and are reviewed by Tseng 59 andMarshall, Newton, and Orr.60 Chemically, carragheenin is not identicalwith true agar, the most obvious difference being the very much higherorganic sulphate content (25-35%).Early work on the constitution ofcarragheenin is summarised by Tseng59 and structural studies are reviewedby Jones and Smith62 and Percival.63 ’The main structural feature wasshown to consist of a chain of 1 : 3-linked a-D-galactopyranose units withthe sulphate group located on C(4,.723 73 Isolation of 2 : 4 : 6-tri-U-methyl-59 C.K. Tseng, in ‘‘ Colloid Chemistry,” Reinhold Publ. Corp., New York, 1946,1.01. VI, p. 629.6o S. M. Marshall, L. Newton, and A. P. Orr, “ A Study of Certain British Seaweedsand their Utilisation in the Preparation of Agar,” H.M.S.O., 1949.61 13. J . Humm, in “ Marine Products of Commerce,” by D. K. Tressler and J. McW.Lemon, Reinhold Publ. Corp., New York, 1951, p. 47.62 J. K. N. Jones and F. Smith, Adv. Carbohydrate C h ~ n z . , 1949, 4, 275.O3 E. G. V. Percival, Quart. Reviews, 1949, 3, 376.64 C. Araki, Menz. Coil. Sci. TecJa., Kyoto, 1953, 2, B, 17.6 5 W.G. M. Jones and S. Peat, J . , 1942, 225.6G V. C. Barry and T. Dillon, Chem. and Ind., 1944, 63, 167.6 7 E. G. V. Percival, Nature, 1944, 154, 673.6 8 C. Araki, J . Chenr. Soc. Japan, 1944, 65, 533.70 E. G. V. Percival and T. G. H. Thomson, J . , 1942, 750.7 1 C. Schmidt, Ann. Chcm. Phavm., 1844, 51, 2972 J,. Buchanan, E. E. Percival, and E. G. V. Percival, J . , 1943, 51.i 3 h. T. Dewar and E. G. V. Percival, J . , 1947, 1622.Carragheenin.69 Idem, ibid., p. 627328 BIOCHEMISTRY.D-galactose from the hydrolysis of methylated, partially degraded, de-sulphated carragheenin has confirmed this ~iew.7~9 75 Much still remains tobe done, however, before the full constitution is settled, for the yield ofgalactose obtained on hydrolysis represents only about two-thirds of theorganic matter present.The isolation of a crystalline derivative of 2-oxo-D-gluconic acid has been rep~rted,'~ but it is by no means certain that thisproduct is present as such in the original material.63 The problem has beenfurther complicated b;y the isolation of L-galactose derivatives from methyl-ated carragheenin.74The electrophoretic, sedimentation , and diffusion properties of carra-gheenin have recently been studied.?? Four samples with different intrinsicviscosities were examined and the results showed that the molecular weight,axial ratio, and estimated diameter of the ellipsoid all increased with theintrinsic viscosity of the sample. All samples were polydisperse and twocomponents were revealed by sedimentation, the amount of the more rapidlysedimenting minor component increasing with the viscosity from nil toabout 12% of the most viscous sample. The mean values obtained werecomparable with those reported for certain cellulose preparations , indicatingthat the major constituent has a linear structure. It is suggested that theminor component with the higher rate of sedimentation may have a differentsize or shape and may be branched.This name was suggested by Tseng 59 for the galactansulphuric acid ester from Iridaea lamina~ioides.7~ From methylation studies 79Hassid concluded that iridophycin consists of 1 : 4-linked p-D-galactopyranoseunits sulphated on C(6).Since all other galactan sulphates from red algaehave subsequently been found to be 1 : 3-linked, Hassid's evidence hasbeen re-examined and re-interpreted by Jones and Smith.62 Mori hasproved conclusively the presence of 1 : 3-linkages by isolating 2 : 4 : 6-tri-0-methyl-D-galactose from hydrolysed, methylated, desulphated iridophycin,and considers from triphenylmethylation experiments *l that the sulphategroup is attached to Cts) and that the glycosidic linkage is a.82A galact an sulphate, similar to carragheenin butwith a much lower sulphate content, has been isolated 83 from Dilseaedulis.The methylated, partially degraded, sulphate-free mucilage onhydrolysis gave a high yield of 2 : 4 : 6-tri-0-methyl-~-galactose, therebyshowing a preponderance of 1 : 3-linked galactose residues, as in carrag-h e e ~ ~ i n . ~ ~ The sulphate group was assigned to C(4).The mucilage con-tained a uronic acid residue, and the ratio of galactose : sulphate : uronicacid was estimated to be 9 : 2 : 1.A very similar mucilage, with galactose : sulphate : uronic acid in the ratio9 : 4 : 1, has been extracted from Dumontia incrassata, which belongs to thesame family (Dumontacez) as Dilsea edulis but is commoner.85 Periodateoxidation indicates the majority of the inter-galactose links to be 1 : 3.Iridophycin.Other PoZysaccharides.74 R. Johnston and E. G. V. Percival, J., 1960, 1994.i 5 T. Dillon and P. O'Colla, Proc. Roy. Irish Acad., 1951, 54, B, 61. I6 E. G. Young and I;. A. H. Rice, ,I. Biol. Chem., 1946, 164, 35.# ' W. H. Cook, R. C. Rose, and J. R. Colvin, Biochim. Biophys.Ada, 1952, 8, 595.78 W. 2. Hassid, J . Amer. Chem. Soc., 1933, 55, 4163.79 Idem, ibid., 1935, 57, 2046.Idem, ibid., 1949, 23, 81.V. C. Barry and T. Dillon, Proc. Roy. Irish Acad., 1945, 60, B , 349.x 4 T. Dillon and J. McKenna, ibid., 1950, 53, B, 45.80 T. Mori, J . Agvic. Chem. SOC. Japan, 1943, 19, 297.82 T. Mori and T. Fumoto, ibid., 1949, 23, 81.*s Idem, Nature, 1950,165, 31 8BLACK : CONSTITUENTS OF THE MARINE ALGB. 329The structure of the xylan s6* 87 of Rhodymenia palmata has recently beeninvestigated.88$ 89 Periodate oxidation and methylation showed both1 : 4- and 1 : 3-links between the D-xylose units. It therefore differs fromesparto xylan.w The isolation of a mannan from Porphyra umbilicalis bycopper precipitation of a hot 20% sodium hydroxide extract has recentlybeen reported.91 Hydrolysis of the completely methylated derivativegave chiefly 2 : 3 : 6-tri-O-methyl-~-mannose, indicating a predominating1 : 4-linkage.The outer membrane of Porphyra tenera is reported to containa polysaccharide which on hydrolysis gives chiefly m a n n o ~ e . ~ ~Funorin, a gluey substance present in species of Gloeopeltis which haslong been used in the Orient as sizing material for textiles and paper,59has not been examined chemically to any extent, but the limited informationavailable points to its being a galactan s ~ l p h a t e . ~ ~ , 94 Other references to thepresence of galactan sulphates in red algz have been collected by Jones andSmith 62 but no structural studies have been carried out.Little work appears to have been carried out on seasonal variations incomposition of red algz or on any of the other factors which have beenshown to affect the chemical composition of the brown algz.Macphersonand Young,95 in their study of the chemical composition of marine algae ofNova Scotia, included five red algz collected at one time of the year andanalysed them for water, nitrogen, ash, lipids, calcium, phosphorus, andiron. The biochemistry of the RhodophyceE has been reviewed by Kylhg6Carbohydrates of Green Marine Algae (Chlorophyceae) .-No completereview has yet been given for the green algz, probably since very littlechemical work has been carried out on these plants. Reference was made in1937 to evidence presented by S.Endo that glucose was the first product ofphotosynthesis in Codium latum whereas in CLadoPhora wrightiana fructosewas the first-detected sugar,Q7 and in 1942 to the rhamnose-containingpolysaccharide from Ulva Zactuca.98 In Japan a similar type of poly-saccharide, considered to be a polymer of L-rhamnose and uronic acid, hasbeen isolated from Ulva pertusa 99 and Enteromorfiha compressa.lW Kylin lolalso studied the polysaccharides of these two algz and isolated two pectin-like materials, one (ulvin) water-soluble, and the other (ulvacin) water-insoluble. Ulvin he showed to be a sulphuric acid ester containing a methyl-pentose, while the composition of ulvacin was undetermined. From Clado-phora rupestris, Kylin l02 isolated what he regarded as a reserve carbo-hydrate, resembling the paramylon of the Euglenacez.Also, an extractof this alga, on acid hydrolysis, showed the presence of sulphuric acid, and8 6 C. Sauvageau and G. Denigks, Compt. vend., 1922, 174, 791.8 7 V. C. Barry and T. Dillon, Nature, 1940, 146, 620.E. G. V. Percival and S. K. Chanda, ibid., 1950, 166, 787.89 V. C. Barry, T. Dillon, B. Hawkins, and P. O'Colla, ibid., p. 788.S. K. Chanda, E. L. Hirst, J. K. N. Jones, and E. G. V. Percival, J., 1950, 1289.9 1 J. K. N. Jones, J . , 1950, 3292. 92 T. Miwa, Japan. J . Botany, 1940, 11, 41.g3 K. Aoki, Bull. J a p . SOC. Fish., 1935, 3, 359; 1937, 6, 88, 145, 182; 1938, 7, 25,84 A. G. Ross, unpublished work.95 M. G. Macpherson and E. G. Young, Canad. J . Res., 1949, 27, C, 73.9 6 H.Kylin, Kgl. Jvsiogr. Sallsk. LunZ Forh., 1943, 13. 51.9 7 A. G. Pollard, Ann. Reports, 1037, 34,452. F. W. Norris, ibid., 1942, 39,235.)o9 S. Miyake, K. Hayashi, and Y. Takimo, J. SOC. Tvop. Agr. Tohoku Imp. Unzv.,101 H. Kylin, Kgl. fysiogr. Sallsk. Lzcnd Forh., 1946, 16, 102.102 Idem, ibid., 1944, 14, 221.168.1938, 10, 232. loo S. Miyake and K. Hayashi, ibid., 1939, 11, 269330 BIOCHEMISTRY.galactose was confirmed, indicating that the substance was probably agalactan sulphate. Recent analyses of Ulva lactuca and EnteromorpkaJlexuosa for crude proteins, ash, fats, and fibre,lo3 and of Ulva Zactuca andEnteromorpha intestinalis for nitrogen, fats, ash, calcium, phosphorus, andiron,95 have been reported while cell-wall studies in the Chlorophyceae havebeen carriedWork on the evolution of dimethyl sulphide from the algz has beenextended to Enteromorpha intestinalis, and 2-carboxyethyldimethylsulphon-ium chloride has been isolated from this alga.lo5A further study of Ulva pertusa has led to the isolation from it by steam-distillation of a new acidic compound, ulvaic acid (C18.Hq60,).106Other Constituents of Marine Algze.-As great similarity occurs in thegroups of algae already discussed in regard to the following constituents,a brief review will now be given of the proteins, lipids, sterols, vitamins, andpigments in these algz.Lemberg and Legg lo7 have reviewedthe earlier work on algal chromoproteins and their photosynthetic role hasbeen considered.loS, 10% 110 A review by Lugg ll1 has dealt with the earlierwork on the amino-acid composition of various marine algz.A concisereview of peptide studies and amino-acid composition of marine algz occursin a recent paper by Channing and Young 112 and the literature on the freeamino-acids, iodo -amino-acids, and isolated proteins has been surveyed. l l 3 9 114Results of previous work 115 on algal amino-acid com-position are now known to be erroneous l 1 2 ~ and the protein amino-acidsof different algz are qualitatively similar 112* 114 although the free andpeptide amino-acids of various algz differ.ll2, 113 Roche and Lafon 117originally reported the detection of 3 : 5-di-iodotyrosine in Laminariasacchnrina and L. jexicaulis, but conflicting evidence has arisen. 114 Morerecent work 11* on iodo-amino-acid stability and iodine lability underconditions of barium hydroxide hydrolysis, in which 1311 was used, seems toindicate that all iodo-amino-acids, except thyroxine, are unstable, theiriodine being labile.It has also been shown 118 that Rlzodymenia palmata,Laminaria digitata frond, and ULva lactuca have the ability to synthesiseiodo-amino-acids and other iodine compounds in the dark though this abilityseems to be absent in L. digitata stipe and Fucus vesiculosus.An examination of the peptides of Pelvetia cnnaliculata 112using l-bromo-2-fluoro-3 : 5-dinitrobenzene followed by a counter-currentProteins, amino-acids and peptides.Amino-acids.Peptides.lo3 J. H. Axtmayer and H. Estremera, El Cvisol, 1950, 4, 19.loQ 1;.Nicolai and R. D. Preston, Proc. Roy. SOC., 1953, B, 140, 244.lo5 I<. Bywood and F. Challenger, Biochem. J . , 1953, 53, xxvi.loo T. Katayama and T. Tomiyama, J . Fac. Agv. Kyushu Univ., 1950, 9, 271.lo’ R. Lemberg and J. W. Legg, “ Hematin Compounds and Bile Pigments,” Inter-lo8 S. Granick, Ann. Rev. Plant Physiol., 1951, 2, 115.log E. I. Rabinowitch, ibid., 1952, 3, 229; “ Photosynthesis and Related Processes,”110 H. 14. Strain, in “ Photosynthesis in Plants,” Iowa State College Press, Ames,1’2 D. RI. Channing and G. T. Young, J . , 1953, 24S1.113 C. B. Coulson, Chem. and Ind., 1953, 971.11’ A. Mazur and H. T. Clarke, J . Biol. Chenz., 1938, 123, 729; 1942, 143, 39.J . W. H. Lugg, Adv. Protein Chem., 1949, 5, 249.11’ J.Roche and M. Lafon, Comfit. rend., 1940, 229, 481.lL8 R. Scott, unpublished work.science Publ., New York, 1949, pp. 127, 145, 571.Interscience Publ., New York, 1945, pp. 417, 476.1949, p. 163. 111 J. W. H. Lugg, A d v . Protein Chenz., 1949, 5, 229.11* Idem, ibid., p. 997BLACK: CONSTITUENTS OF THE MARINE ALGAL 33 1partition of the bromodinitrophenyl-peptides showed that glutamic acid wasthe major peptide component.Photosynthesis experiments,llg following those of Haxo andBlinks,l*O show that phycocyanin and chlorophyll of the Rhodophyceaeprobably obtain energy from phycoerythrin-absorbed light. Swingle andTiselius, using phycoerythrin from Ceramium rubrwm, demonstrated thattricalcium phosphate columns could be used for chromatographic separ-ation.121 Ultra-centrifuge and electrophoretic studies lZ2 of phycoerythrin(Callithamnion spp.) isolated chromatographically on tricalcium phosphatesuggest the presence of two protein components.The liberated phyco-erythrobilin is oxidised in air to a blue product similar to phycocyanobilin.122Ulva pertusn proteins have been fractioned 123 with water, sodium chloridesolution, and weak alkaline extractants, their isoelectric points determinedand their spectrographic properties examined. The amino-acids of isolatedproteins of various marine algae 114 and Oscillatoria phycocyanin 124 havebeen examined by paper-chromatography; those of dried a l p appear to bedeficient in histidine,l14 and it is suggested that phycocyanin may containhydroxyglutamic acid.124 The presence of alginic acid in the Phzophycezehas, so far, prevented the isolation of a relatively pure protein.l14 It hasbeen found that, 2s more protein nitrogen is precipitated, it is associatedwith more alginate.lZ5 An alginate-protein complex is said to be formedbetween their two isoelectric points, at high alginate : protein ratios,126when casein, gelatine, and egg albumen are used, although electrophoreticevidence of this has not been found for ovalbumin in less acid solutions andwith lower alginate : protein ratios.127Lifiids. Although in the 1942 Reports 128 reference was made to areview on the lipoid constituents, this dealt entirely with the carotenoids andsterols. No review of the algal fats has yet appeared in these Reports.Tsujimoto in 1925 isolated the fatty acids from seven species of a l p commonto Japan 129 but no work of a chemical nature was carried out for severalyears thereafter. Russell-Wells in 1932 determined the fats in the brownalgae common to Britain and established a relation between the fatty con-stituents and the depth of immersion of the algae; the percentage of crudefats decreased with the depth of immersion while the unsaponifiable residueconversely increased.130 During the next few years a systematic study ofthe fats and their properties was carried out in Japan.131, 132 The fatty acidsProteins.119 C.S. French and V. K. Young, J . Gen. Physiol., 1953, 35, 873.120 F. T. Haxo and L. R. Blinks, ibid., 1950, 33, 389.lZ1 S.M. Swingle and A. Tiselius, Biochem. J., 1951, 48, 171.122 ,4. A. Krasnovskii, V. B. Evstigneev, G. B. Brin, and V. A. Gavrilova, DokladylZ3 M. Takagi, Bull. Fac. Fish. Hokhaido Univ., 195(3, 1, 35.124 E. C. Wassink and H. W. J. Ragetli, Proc. -4cad. Sci. Amsterdam, 1952, 55, C, 462.125 D. G. Smith and E. G. Young, 1st Int. Seaweed Symp., 1952, 64.126 V. C. E. Le Gloahec, U.S.P. 2,430,180/1947.12’ D. G. Smith and E. G. Young, J . Biol. Chem., in the press.I z 8 F. W. Norris, Ann. Reports, 1942, 39, 229.129 31. Tsujimoto, Chem. Umschau, 1925, 32, 126.130 B. Russell-Wells, Nature, 1932, 129, 654.131 E. Takahashi, K. Shirahama, and S. Tase, J . Chem. SOC. Japan, 1933, 54, 619;1935, 56, 1250.E. Takahashi and K. Shirahama, ibid., 1936, 57, 411 ; E.Takahashi, K. Shira-hama, and N. Ito, ibid., 1938, 59, 662 ; E. Takahashi, K. Shirahama, and N. Togasawa,ibid., 1939, 60, 56.Akad. Nauk S.S.S.R., 1952, 82, 947332 BIOCHEMISTRY.identified were palmitic, stearic, myristic, decanoic, octanoic, hexanoic,linolenic, and oleic. The unsaponifiable matter gave a sterol “ pelvesterol ”(later identified with fucosterol), hydrocarbons such as C,@36, C2?H3,, andunsaturated t e r ~ e n e s . l ~ ~ Recently the composition of the oil of Dzctyopterisdivaricata has been examined; 134 steam-distillation gave about 1% of anoil consisting of sesquiterpenes and sesquiterpene alcohols, and from thesecadinene and (-)-cadino1 have been isolated.Sterols. At intervals reviews of algal sterols have appeared in thesereports.134a Since the last , the constitution and stereochemical configur-ation of fucosterol, as given by M a ~ P h i l l a m y , ~ ~ ~ have been confirmed by theisolation of acetaldehyde and 2Poxocholesterol on ozonolysis.136 Bergmannand Klosty 13’ independently verified these results by converting fucosterolinto 24-oxocholesterol by way of isofucosteryl methyl ether which was trans-formed into 24-oxocholesteryl acetate. A method is described for thedetermination of fucosterol in algz; 138 crude fats, extracted with ether,are saponified and the fucosterol is determined colorimetrically in the un-saponifiable fraction by a method based on the Liebermann-Burchardtreaction. A correlation was found between the percentage of fucosterol andthe total crude fats, the sterol being highest in the most exposed alga,Pelvetia canaliculata (0.28% on the dry basis), and decreasing with thedegree of immersion of the alga to less than O.lyo in L.cZoustoni frond.Vitamin A . Considerable work, particularly in Japan, has been carried outon the vitamin content of the a l p . Presence of vitamin A has not been con-firmed although Freudenthal 139 has shown that algz in very small doses cansupply all the vitamin A and D requirements of the rat. He investigated threespecies of algae, Furcellaria fastigiata, Fucus serratus, and F . vesiculosus, byfeed-ing increasing amounts to rats kept on a diet deficient in vitamins A, D, and E.P-Carotene is widely distributed in the algae; according to Seybold andEgle 140 the total carotenoid content is from 29 to 190 mg. per 100 g.of drymaterial in the Phzophycez, 9 3 4 0 6 in the Chlorophycea3, and 12-158 inthe Rhodophyceae.Thiamine, determined in a number of algae, variesconsiderably in the different portions of the plant, particularly in theLaminariae.141 In L. saccliarina and L. digitata the thiamine contentvaried from 7-25 and 9-35 in the growing portion of the frond to 1.31 and2-56 pg. per g. of dry weight in the upper part of the fronds respectively.The riboflavin content of a number of red, brown, and green algz commonto Japan has recently been r e ~ 0 r t e d . l ~ ~ AEaria crassifolia, Laminaria.japonica, Porphyra temra, and Enteromorpha linza, for example, containedrespectively 1000, 940, 3700, and 2500 pg.per 100 g. of the dried samples.Vitamin B complex.133 K. Shirahama, J . Agvic. Chem. SOC. Japan, 1935, 11, 980; 1936, 12, 621; 1937,134 M. Takaoka and Y . Ando. J . Chem. SOC. Japan, 1951, 72, 999.134a C. W. Shoppee, Ann. Reports, 1947, 44, 175.135 H. B. MacPhillamy, J . Amer. Chem. SOC., 1942, 64, 1732.136 D. H. Hey, J. Honeyman, and W. J. Peal, J.. 1950, 2881 : J . , 1952,4836.13’ W. Bergmann and M. Klosty, J . Amer. Ckem. Soc., 1951, 73, 2935.138 W. A. P. Black and W. J. Cornhill, J . Sci. Food Agric., 1951, 2, 387.lS0 P. Freudenthal, ‘‘ Om Vitamin I Alger,” Nyt. Nordisk Forlag, Copenhagen, 1949.140 A. Seybold and K . Egle, Jahrb. wiss. Bot., 1938, 86, 50.141 G. Gerdes, Avch. Mikrobiol., 1951, 16, 53.142 M. Tsujimura, K.Tabei, and T. Wada, J . Agric. Chent. SOC. Japan, 1952, 26, 11.13, 705; 1938, 14, 349, 415,421, 743BLACK CONSTITUENTS OF THE MARINE ALGE. 333Although there is no certain evidence of the presence of vitamin B,, interrestrial plants, Ericson 143 has detected it in several algz, e.g., PoZysiphoniaizigrescens and Pelvetia canaliculata gave B,, (cobalamin) activity corre-sponding respectively to 1.0 and 0.5 pg. of B,,.per g. of dry weight. Inorder to determine whether the B,, was synthesised by the alga, or was ofbacterial origin and then concentrated by it, Ericson 143 studied the uptakeof radioactive cobalt and B,, by some marine algae, and concluded that theB,, was in fact of bacterial origin. Chromatographic, ionophoretic, andspectrophotometric methods for the examination of vitamin B,, and othergrowth factors have recently been ~tudied,l4~> lg5 and growth factors relatedto B,, and folinic acid in some brown and red algae have been estimatedby the agar cup plate method.146 The bio-autographic separation of vitaminB,, and the various forms of folinic acid in these algze has, in addition, beenaccomplished.147 Also, by use of paper-chromatographic and bio-auto-graphic methods, a t least nine growth factors for Streptococcus faecalishave been identified in aqueous extracts of dried samples of algae suchas L.saccharina, F. vesiculosus, Polysiphonia nigrescens, and Rhodomelasubfusca. 148Considerable work done on ascorbic acid in algae has beenreviewed by Tsuchiya 149 who studied seasonal variation and effects oftemperature, pH, and chlorine content on ascorbic acid in Ulva pertusa,Enteromor$ha spp., and Gracilaria confervoides.In U. pertusn it reacheda maximum of 241.23 mg. per 100 g. of dry weight at the beginning ofJanuary, in Enteromorpha spp. a maximum of 238-85 at the end of thesame month, but in Gracilaria confervoides it stayed a t a level of 148.63-167.62 from January to May. It was also found lg9 that the ascorbic acidcontent was influenced by physical and chemical conditions in a mannersimilar to that in the higher green plants. The ascorbic acid content (indo-phenol determination) of marine a l p common to Hokkaido has also beenreported : l5O it was low in two species of Chlorophyceae and fifteen speciesof Rhodophyceze (4-65 mg.per 100 g. of dry wt.) but greater in fourteenspecies of Phzophyceae (309-888 mg.).Doubt still exists as to the occurrence of the antirachiticvitamins in plants and Rygh 151 stresses that determinations should berestricted to biological tests. He extracted the vitamin D fraction from aseries of plants with ether and obtained values corresponding to 2-5-20microunits of vitamin D per g. of dry wt. of plant ; with drifting green algaehe obtained still higher values in agreement with Johnson and Levringwho determined the vitamin D content of a number of brown and greenalgz by the rat assay method. F. vesicuZosus gave an antirachitic effectcorresponding to a content of 5 microunits per g. of dry matter. JohnsonVitamin C.Vitamin. D.143 L.-E. Ericson, Chem. and Ind., 1952, 829.144 Idem, Acla Chem. Scand., 1953, 7, 703.145 L.-E. Ericson and A. G. M. Sjostrom, ibid., p. 704.148 L.-E. Ericson and Z. G. Bjnhidi, ibid., p. 167.14’ 2. G. Bknhidi and L.-E. Ericson, ibid., p. 713.148 L.-E. Ericson, E. Widoff, and 2. G. BAnhidi, ibid., p. 974.lQ9 Y . Tsuchiya, Tohoku J . Agvic. Research, 1950, 1, 97.150 Y. Ishihara, S. Umemoto, and Y . Matsubara. Mem. Fac. Agr. Hokkaido Univ.,152 N. G. Johnson and T. Levring, Svenska Hydrogrufisk. B i d . Komm. Skrifter, 1947,1951, 1, 83.1, No. 3, 1.151 0. Rygh, Research, 1950, 3, 577334 BIOCHEMISTRY.and Levring 152 found that the higher algae, growing just below the surfaceor floating in the sea and exposed to the active ultra-violet radiation of thesun, did possess some antirachitic activity and also concluded that pro-vitamin in varying amounts is present in many marine organisms. Furtheranalysis made it very probable that the provitamin is 7-dehydrocholesterolor the D, provitamin.a-, y-, and &Tocopherols have been found in the threelittoral brown algae examined, F. vesiculosus, Ascoj5hyZZum nodosum, andPelvetia canaliculata, while only a-tocopherol has been found in L. c l o ~ s t o n i . l ~ ~This vitamin appears to undergo considerable seasonal variation, increasingfrom 13.8 mg. per 100 g. of dry matter in F. vesiculosus, 15.6 in Ascophyllumnodosum, and 22-9 in Pelvetia canaliculata in the January samples to 27.2,29.8, and 34.7 in the September samples.Brief reference has been made to the algal pigments inprevious reports.128: 1549 1557 156 An extensive review and bibliography up to1945 have been prepared by A. H. Cook; 15' work t o 1951 has been reviewedby Strain.157a Since then, Karrer and Tappi 158 chromatographically separ-ated the carotenoid pigments from Cladophora glomerata, by absorptionspectra showing presence of p-carotene, xanthophyll, xanthophyll epoxide,and violaxanthin. thestructure, synthesis, and physiological significance of the carotenoids andvitamin A are discussed : the authors comment on the appearance of un-usual carotenoids in individual organs, such as that of a-carotene in thespermatozoids of the Fucus species, and how this has prompted the suggestionthat pigmentation is associated with motility or the chemotactic sensitivity.Carotenoid biogenesis has been recently reviewed by Goodwin ; 160 no workappears to have been carried out on carotogenesis in the algz.Cook, Elvidge, and Heilbron 161 have studied chemotaxis between thegametes of the Fucaceae. Cell-free preparations of F. serratus and F. vesi-culosus eggs have been obtained which exert a chemotactic attraction on thesperms of F . sermtus, F. vesiculosus, and F. spiralis. The chemotacticprinciple was found to be easily expelled from aqueous solution by a streamof inert gas, and could be recovered in a cooled receiver, but it was not fullyidentified.le2 Dilute solutions in sea-water of a number of simple organiccompounds (hydrocarbons, ethers, and esters) stimulate the cell-free pre-parations from Fucus eggs and cause attraction of the spermatozoa of F.serratus and F. vesiculosus in the same manner. The results indicated thatn-hexane or a closely related hydrocarbon might be the chemotactic principle.In view of the ability of algae to concentrate elements present in sea-water, the importance of this in the disposal of radioactive waste materialsinto the sea is manifest. Black and Mitchell le3 have reviewed this fieldVitamin E.Pigments.In a review by Sir Ian Heilbron and A. H.153 F. Brown, Chem. and Ind., 1953, 174.154 A. W. Stewart, Ann. Reports, 1914, 11, 144.155 A. G. Pollard, ibid., 1937, 34, 453.15' A. H. Cook, Biol. Reviews, 1945, 20, 115.157a H. H. Strain, " Manual of Phycology," 1951, Waltham, Mass., U.S.A., p. 243.158 P. Karrer and G. Tappi, Helv. Chim. Acta, 1950, 33, 2211.150 Sir Ian Heilbron and A. H. Cook, Endeavour, 1951, 10, 175.l60 T. W. Goodwin, J. Sci. Food Agric.. 1953, 4, 209.161 A. H. Cook, J . A. Elvidge, and Sir Ian Heilbron, R o c . Roy. Soc., 1948, B, 135, 293.lae A. H. Cook, J . A. Elvidge, and R. Bentley, ibid., 1951, B, 138, 97.163 W. A. P. Black and R. L. Mitchell, J . Marine Biol. Assoc., 1952, 30, 575.156 R. A. Morton, ibid., 1949, 46, 247BLACK CONSTITUEXTS OF THE MARINE ALGW. 335and have determined trace elements in the common brown algz and insea-water. A seasonal variation was noted as well as considerable variation inthe content of these elements among different species from the same habitat.The extent to which the algae concentrate these elements has been calcul-ated; e g . , F . sfiraZis contains 10,000 times more titanium than the sur-rounding seawater. Kelly,ls4 and Roche and Yagi,165 have stcdied theuptake of radioactive 1311. The thalli of L. jlexicaulis and L. saccharinawere immersed in sea-water containing Na1311. Radio-autographs showedthe 1311 fixed in certain regions of the tissue.165 At least 80% remained ininorganic form while some was converted into mono- and di-iodotyrosine.In Japan, recent interest has been directed to use of seaweed as a growthmedium for yeast. Two suitable species of yeast which were isolated(Candida spp. No. 1 and 2) had high mannitol-assimilating powers of 87.4and 61.8% respectively 166 (cf. ToruZa zitiZis 19%). The brown alga, Eckeloriacuva, was a suitable substrate, and optimum conditions were worked outfor the growth of the yeast on hydrolysates of this alga.167 On the otherhand, an Ulva sp. was found unsuitable for yeast production, as also werethe alkaline extracts and waste liquors from the alginate industry. The acidleach, however, before extraction of the alginic acid could be utilised.168Extracts of several species of Chlorophyceae, Rhodophycez., and Phzeo-phyceae common to the central Californian coast have been found to inhibitthe growth in vitro of one or more species of pathogenic bacteria.169 Thecrude ether-extract of Rhodomela Zarix li0 contains iodine 0.05, bromine37.7, chlorine nil, total halogen 37.6, and total ash 1.0%. Further testsindicated that a brominated phenolic compound may be the active antibiotic.Blinks has recently reviewed work on the physiology and biochemistryof the algz.,171 and a recent monograph by Fogg gives valuable informationon their metab01isrn.l~~W. A. P. B.J. S. D. BACON.D. J. BELL.141. A. P. BLACK.G. D. GREVILLE.D. J. MANNERS.H. B. STEWART.164 S. Kelly, &ol. Bull., 1953, 104, 138.165 J. Roche and Y. Yagi, Compt. refid. SOC. Biol., 1952, 146, 642.lfi6 Y . Tomiyasu and B. Zenitani, J . A p i c . Cltem. SOC. Japan, 1951-52, 25, 406.16’ Idem, ibid., p. 479. 168 Idem, ibid., 1952, 26, 6.lG9 R. Pratt, H. Mautner, G. M. Gardner, Y.-H. Sha, and J. Dufrenoy, J . Amer.Phnrm. Assoc., 1951, 40, 575.170 H. G. Mautner, G. M. Gardner, and R. Pratt, ibid., 1953, 42, 294.171 L. R. Blinks, “ Manual of Phycology,” Waltham, Mass., U.S.A., 1951, p. 263.17* G. E. Fogg, “ The Metabolism of Algae,” Methuen & Co., Ltd., London, 1953

ISSN:0365-6217    

DOI:10.1039/AR9535000281

出版商:RSC    

年代:1953

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ANALYTICAL CHEMISTRY.1. INTRODUCTION.THERE have been at least two attempts recently to distinguish betweeninorganic and organic analysis, in the special context of organic qualitativeanalysis, by defining inorganic methods as those used largely for the identi-fication of elements or ions, organic tests being more concerned with theidentification of functional groups or even of compounds as a whole. It istrue that in the past this broad distinction has been generally accepted. Itis equally true that there have been notable exceptions, where the inorganicanalyst has not been content to identify only the elements or ions present,since this is no answer to his problem. A classical instance of this, whichis still receiving attention,2 is the analysis of complex mixtures of phosphates.In such a problem the percentage of phosphorus present gives little guidanceon the nature of the mixture.Each of the phosphates must be characterisedand determined separately.There are indications that the inorganic analyst, faced with multiplyinginvestigations on the covalent compounds of the non-metals, will have topay more attention to compound analysis. In the analysis of a simplemixture of, say, chlorine trifluoride and fl~orine,~ the elementary compositionwill probably be sufficient if one is certain that no other constituents arepresent. It only needs the mixture to be complicated by the addition ofa third constituent to require an investigation of a completely different order.Such mixtures, through the rapidly expanding chemistry of fluorine, mustbe met with much more frequently in the future.Again, in the strivingafter high purity which new industrial demands have emphasised in the pastfew years, it is often the form of the impurity rather than its elementalcharacter which is of importance-the precise oxide or oxides, let us say, andthe relative proportions of them that are present, rather than the fact thatoxygen is the contaminant. This is vital information which the analyst isexpected to supply.All of this indicates that the analyst who in the past has regarded himselfas being chiefly concerned with inorganic materials, and who does notenvisage any change in this situation in the future, may very well requireto approach his problems from a different point of view.He may find itnot only advantageous, but even necessary, to familiarise himself with theapproach of the organic analyst to his problems. As a consequence, it islikely that physical methods may prove to have an even more importantpart to play in some sections of inorganic analysis than in the past ; it is sooften only through instruments that the organic chemist is able to get aproper analysis, in the molecular sense, of the complex mixtures of relatedcompounds which confront him.It may be retorted that the wise inorganic analyst has, in the past, made1 F. Feigl, Mikvochem. A d a , 1953, 157 ; R. Palland, Ann. Chim. analyt., 1952, 34, 194.a W. Dewald and H. Schmidt, 2. anal. Chem., 1952-1953, 137, 178; 1953, 138, 91 ;139, 359; H.Etienne, Ind. Chim. belg., 1953, 2, 340.3 S. Katz and J . T. Barr, Analyt. Chem., 1953, 25, 619WILSON : INTRODUCTION. 337extensive use of instrumental analysis; the Reports for the past few yearscertainly appear to bear this out, since a glance a t them shows the extent towhich the instrument has penetrated into the general analytical laboratory.Closer examination of the situation reveals, however, that on the inorganicside the bulk of instrumental work has still been directed towards elementor ion analysis. Other applications have tended to be regarded as specialproblems. The Reporter would venture to predict that the signs of achange in this attitude, spasmodic during the past few years, will becomemore frequent; that routine molecular analysis is a problem that will cometo affect much more acutely all analysts concerned with inorganic material;and that as a consequence, the division generally held to separate inorganicand organic analysis will become considerably less sharply defined within ashort period of time.During the past year developments have been mainly along lines whichcould, on the whole, have been fairly expected. That is to say, there islittle that one could call inspired advance, and work has largely been basedon previous discoveries.Perhaps this contention requires some elaboration.Although much of the work is important, the development of a new reagentfor a particular cation, or the use of an old reagent in a new way, is notnecessarily to be included in the category here referred to as “ inspired ”work.Such work usually involves the application of a completely newprinciple, and sometimes the jettisoning of a mass of preconceived ideas builton a generation of existing research. As a minor example of what is meant,one paper may be picked out without any suggestion that it is a betterexample than others dealt with here and there throughout this Report.Much work has gone into devising a satisfactory medium for the decom-position of organic nitrogenous material before Kjeldahl determination ofthe nitrogen in the form of ammonia. Sulphuric acid, with varying additionalsubstances whose function is not always clear, is normally used. S. M.Woods, D. Scheirer, and E. C. Wagner,4 starting from first principles, pointout that strong reduction, rather than the usual oxidation, is the logicalmeans of achieving the degradation, and have carried out some preliminarywork on a method which, whatever its experimental merits may ultimatelyprove to be, at least has the veritable advantage of an unusual approach.While on this subject of new methods, the Reporter would comment onthe unnecessary frequency with which methods are advertised in the liter-ature as ‘‘ new methods ” for various purposes.This seems an undesirableemphasis, doubly so when, as often happens, the reader finds that the methodis a revival of a method current thirty or forty years ago, or is merely anadaptation of a method established by another worker.The complaint voiced in last year’s Report regarding the naming ofreagents can be reiterated.The lot of the analytical chemist is made noeasier when he encounters as a reagent “ 2-(2-hydroxy-3 : 6-disulpho-l-napht hy1azo)-benzenearsonic acid (Thorin) , also known as 1- (2-arsono-benzeneazo)-Z-naphthol-3 : 6-disulphonic acid, and under the synonymsThoron and Naphtharson.” Some sort of comprehensive register of thenames, trade names, and abbreviated names of reagents is urgently required.The form of this year’s Report follows in general those of the past twoAnalyt. Chem., 1953, 25, 837.D. W. Margerum, C . H. Byrd, S. A. Reed, and C . V. Banks, ibid., p. 1219338 ANALYTICAL CHEMISTRY.years. Where possible, as for example in the order with which the inorganicelements are considered, the Reporter has tried to utilise the UniversalDecimal Classification.This classification, however, pa.rticularly in thesection dealing with analytical chemistry, is quite inadequate to deal withthe range of topics falling within the scope of the Report, so that departuresfrom the strict arrangement are numerous and inevitable.2. GENERAL.Several useful textbooks have appeared dealing primarily with industrialinorganic analysis.’ The modern approach required by the analyst is dealtwith in general terms by D. W. Kent- Jones,s and the training of analysts,both as it has been in the past and as it ought to develop in the future, hasbeen discussed by J . H a ~ l a m . ~ The present position, and likely develop-inents in the future, have been outlined for microchemistry lo and for clinicalanalysis.ll Methods at present used and likely to prove of use in analysingmicrogram and submicrogram amounts of material, particularly in dilutesolution, have been described.lZ The apparatus and techniques which canbe used for ordinary inorganic analysis on the microgram scale have beendescribed in detail.13E.C. Yehle l4 has investigated the effects of laboratory variation inassessing from analytical results the true variation from one batch of materialto another, and has pointed out that occasionally the method of analysismay be a significantly more important source of apparent variation than thevariables actually arising in production. The indirect analysis of three-component systems such as mixtures of the chloride, bromide, and iodide ofpotassium, by the determination of three equivalents, has been discussedby H.Bode.15 It is shown that the three equivalents must be obtainedfrom truly independent determinations, and that it will always be difficult,in any such system, to find three independent equivalents that can be deter-mined with sufficient accuracy to be useful for analytical purposes. Amathematical simplification of the simultaneous equation method of deter-mining multi-component systems, applicable when only one component isrequired, has been proposed as a solution in selected cases.16An electrically heated oven l 7 and a heating block which can be fittedfor a wide variety of microanalytical apparatus,18 both of which can be usedwith automatic temperature control, have been described.A collectedaccount of a wide variety of small items of apparatus including stirring andallied devices, apparatus for inorganic and organic analysis, for electro-Brit. Std. Specif. 1000 : Vol. 2, Pt. 2, 1943.W. F. Hillebrand, G. E. F. Lundell, H. A. Bright, and J. I.,,Hoffmann, “AppliedInorganic Analysis,” 2nd Ed., New York, 1953 ; R. S. Young, Industrial InorganicAnalysis,” London, 1953 ; F, Specht, “ Quantitative anorganische Analyse in derTechnik,” Weinheim, 1953. /. Roy. Inst. Chem., 1953, 77, 479.Ibid., p. 482. 10 C. L. Wilson, Mikrochim. Acta, 1953, 58.l2 L. B. Rogers, J . Chem. Educ., 1952, 29, 612.1 4 Analyt. Chem., 1953, 25, 1047.l1 R. M. Archibald, Analyt.Chem., 1953, 25, 2; G. Glick, Chem. Eng. News, 1953,l3 H. M. El-Badry and C. L. Wilson, Mikrochem. Mikrochim. Acta, 1952-1953, 40,l5 2. anal. Chem., 1953, 139, 101.l6 E. Allen and W. Rieman, Analyt. Chem., 1953, 25, 1325.** Idem, ibid., p. 245.31, 139.141.R. T. E. Schenclr and T. S. Ma, Mikrochem. Mikrochim. Acta, 1952-53, 40, 236WILSON GENERAL. 339chemical techniques, and for titration, has appeared.lg The problem ofcleaning glass apparatus, in particular as applied to apparatus contaminatedwith silicone greases, has been discussed by several workers.20Methods have been proposed for a systematic semimicro-analysis ofsilicates,2l and for the determination of various components of complexphosphate mixtures.2 Reviews of recent progress in ferrous22 and non-ferrous 23 metallurgy have been published.The microanalysis of the alkali-met a1 group has been comprehensively e~amined.2~ Reviews of the analyticalchemistry of germanium,25 beryllium,26 aluminium,27 the lanthanons,28thallium,29 uranium,zO and the platinum-group metals 31, 32 have appeared.A critical review has been made 33 of the methods in use for the destructionof organic matter before the determination of trace metals, and the variouscriticisms of such methods are fully discussed. Methods have been describedfor the determination of impurities in germanium and silicon,34 in titaniumand in titanium alloys.36 Analytical applications of liquid amalgamshave been re~iewed.~’Reagents.-G. F. Smith 38 has described a completely safe method for thepreparation of anhydrous perchloric acid from 72% perchloric acid and 20%fuming sulphuric acid.A new edition of a standard work on organic reagentsfor metals has been p~blished.3~ Tetraphenylphosphonium chloride and thecorresponding antimony compound have been proposed 40 as analyticalreagents which produce insoluble compounds with a wide range of simpleand complex anions, thus providing either gravimetric or titrimetric methodsof determination. All the complexes are extractable from aqueous solutionby chloroform. 2. G. Szab6 and M. T. Beck41 have, from theoretical con-siderations, proposed various practical applications of the complexes formedby aluminium with fluoride ions. They have also discussed the behaviourof phosphoric, tartaric, citric, and other acids as complexing agents.Structural determinations by means of X-rays of various compounds ofinterest in analytical chemistry, and in particular of dimethylglyoxime andits nickel complex, of the zinc 8-hydroxyquinoline complex, and of nickellg J.T. Stock and M. A. Fill, Mikrochim. Ada, 1953, 89; I n d . Chem. Chem. Manuf.,2o A. W. Armstrong, Chem. and Ind., 1953, 219; D. M. C. ReilIy, ibid., p. 411;21 R. B. Corey and M. L. Jackson, Analyt. Chem., 1953, 25, 624.22 H. F. Beeghly, ibid., p. 30.24 C. Duval, Ann. Chim. analyt., 1952, 34, 209.25 H. H. Krause and 0. H. Johnson, Analyt. Chem., 1053, 25, 134.26 F. A. Vinci, ibid., p. 1580.27 ill. Kapel, I n d . Chem. Chem. M a n u f , , 1953, 29:,539, 573.28 R.C. Vickery, ‘ I Chemistry of the Lanthanons, London, 1953 ; I n d . Chem. Chem.ag J. R. A. Anderson, Analyt. Chem., 1953, 25, 108.30 C. J. Rodden, ibid., p. 1598.31 W. M. MacNevin, ibid., p. 1612; F. E. Beamish and W. A. E. MacBryde, ibid.,32 R. Gilchrist, ibid.. p. 1617.33 G. Middleton and R. E. Stuckey, Analyst, 1953, 78, 532.34 C. L. Luke and M. E. Campbell, Analyt. Chem., 1953, 25, 1588.36 J. M. Thompson, ibid., p. 1231.3G hl. Codell, C. Clemency, and G. Norwitz, ibid., p. 1432.3 7 W. I. Stephen, I n d . Chem. Chem. Manuf., 1953, 29, 31, 79, 128, 169.38 J . Amer. Chem. SOC., 1953, 75, 184.39 W. Prodlinger, “ Organische Fallungsmittel in der Quantitativen Analyse,” 3rdQ0 €3. 1-1. Willard and L. R. Perkins, ,4naZyt. Chem., 1953, 25, 1634.41 Ibid., p. 103.1953, 29, 56.H. K. Black and R. A. Gill, ibid., p. 519; R. H. A. Crawley, ibid., p. 1205.z3 M. L. Moss, ibid., p. 37.Manuf., 1953, 29, 260, 291.p. 1613.Ed., Stuttgart, 1953340 ANALYTICAL CHEMISTRY.salicylaldoxime, have been described.42 R. J. P. Williams 43 has discussedthe theoretical principles which may be used in choosing the types of reagentlikely to possess selective action towards a metal cation, and on the basis ofthis has made some suggestions for the design of further reagents. Theinformation which may be obtained from magnetic measurements regardingthe structures of complexes has been considered by R. S. Nyholm.44 H.Irving and R. J. P. Williams 45 report that from critical examination of thestabilities of complexes formed by the bivalent cations of the first transitionseries of metals, the order of stability Mn < Fe < Co < Ni < Cu < Znappears to hold fairly generally. Methods for determining stability con-stants have been discussed46 and an attempt has been made to assess theorigin of increase of stability of complexes due to chelate ring formation.47It has been shown that in ethanol, in the absence of water, certain chelatingreactions occur more readily than if water is present.48 The complexes ofp-diketones have been extensively examined.49 Complexes with otherorganic reagents which have a bearing on analytical chemistry and whichhave been examined in some detail include those formed with 2-substituted1 : lO-phenanthrolines,50 4-pyridine-2’-azo-NN-dimethylaiziline, 51 and NN-bis-2-hydro~yethylglycine.~~ Acetylacetone may act both as solvent and ascomplexing agent, and this property, which has been utilised in separationsof copper from zinc, is likely to have more extensive application^.^^ Thestructure of the complex of this reagent with cobalt has been examined.54As in the last few years, more work has been published on ethylene-diaminetetra-acetic acid than on any other single reagent, thus emphasisingthe outstanding versatility of this compound for analytical purposes.Areview of its uses, particularly in p~larography,~~ and a summary of recentanalytical work making use of it 56 have appeared. Measurements havebeen made of its dissociation constant^,^' and the stereochemistry of thecobalt complex has been examined, resolution having been achieved.58Various modifications of existing methods have been devised for thedetermination of calcium in vegetable material,59 or in the presence ofmagnesium and phosphate, separation of the latter being achieved by useof an ion-exchange column,60 of calcium and magnesium in brines,61 inlimestones,62 and in milk; 63 in the last case phosphate is again removed by42 L.L. Merritt, Analyt. Chem., 1953, 25, 718. 43 Analyst, 1953, 78, 586.44 R. S. Nyholm, Quart. Reviews, 1953, 7 , 377. 4 5 J., 1953, 3192.d6 H. Irving and Ii. S. Rossotti, J., 1953, 3397; L. G. Van Uuitert and C. G. Haas,47 C. G. Spike and R. W. Parry, ibid., p. 2726.48 L. G. Van Uitert, W.C. Fernelius, and B. E. Douglas, ibid., p. 3577.48 Idem, ibid., pp. 457, 2736, 2’739; L. G. Van Uitert and W. C. Fernelius, ibid.,51 J. M. Klotz and W.-C. Loh Ming, J . Amer. Chem. Soc., 1953, 75, 4150.52 S. Chaberek, R. C. Courtney, and A. E. Martell, ibid., p. 2185.53 J. F. Steinbach and H. Freiser, Analyt. Chenz., 1953, 25, 881.54 R. 0. Whipple, R. West, and K. Emerson, J., 1953, 3715.5 5 R. L. Pecsok, J . Chem. Educ., 1952, 29, 597.56 M. 0. Lawson, Ind. Ckem. Chem. Manuf., 1953, 29, 299.57 F. F. Carini and A. E. Martell, J . Amer. Chem. SOC., 1953, 75, 4810.58 D. H. Busch and J. C. Bailar, ibid., p. 4574.5s C. C. Strahan and A. W. Moyls, Food Technol., 1952, 6, 333.81 A. de Sousa, Analyt. Chinz. Acta, 1953, 9, 305.6a J. W. Jordan and K.L. Robinson, Chem. and Iizd., 1953, 687; M. D. E. Jonckers,J . Amer. Chem. Soc., 1953, 75, 451.p. 3862. 5O H. Irving, M. J. Cabell, and D. H. Mellor, J., 1953, 3417.G. Brunisholz, M. Gunton, and E. Plattner, Helv. Chim. Acta, 1953, 36, 782.Chim. analyt., 1953, 35, 101. 63 R. Jenness, Analyt. Chem., 1953, 25, 966WILSON : GENERAL. 341ion-exchange. Various interfering elements have been removed as diethyl-dithiocarbamates before calcium and magnesium deterrninati~n,~~, 65 or as8-hydroxyquinoline complexes.65 Magnesium and zinc can be deterrninedtogether by direct titration if the pH is controlled,66 zinc alone being titratedat pH 6.8, and magnesium being subsequently determined at pH 10. Analternative method of control for these two elements uses the zinc ferro-cyanide-ferricyanide system from which the reagent removes zinc, the endpoint being marked by 3 : 3’-dimethylnaphthidine.Magnesium can thenbe titrated in the ordinary way.67 Zinc can be titrated in aluminium andaluminium alloys if the effect of aluminium is prevented by complexingwith citric acid or citrate.68 Although an amperometric titration has beenrecommended for the titration of zinc with ethylenediaminetetra-acetic acid,69it is claimed that the visual end-point obtained by using the usual Solochrome-black indicator is equally go0d.70 Use has been made of the fact that zincand cadmium complexes with cyanide are decomposed by formaldehyde,whereas the cyanide complexes of other metals are more stable, to enabledetermination of these elements in the presence of other heavy metals.71By back titration with thorium nitrate of excess of ethylenediaminetetra-acetic acid, thorium 72, 73 and aluminium 73 have been determined, alizarin-Sbeing used as indicator. Cyanide has been used to mask other heavymetals in the titration of lead 74 and mangane~e.7~ Manganese has alsobeen determined by precipitation as sulphide before t i t r a t i ~ n .~ ~ In thetitration of indium 779 78 tartrate and cyanide are used to prevent interferences.In the titration of iron it is claimed 79 that when thiocyanate is used asindicator the end-point is dependent on the concentration of thiocyanate.Disodium 1 : 2-dihydroxybenzene-3 : 5-disnlphonate and salicylic acid havebeen recommended as alternative indicators to thiocyanate.80 Iron andcopper together can be determined by using photometric end-poink8l> 82Titanium is precipitated from solutions containing ethylenediaminetetra-acetic acid which have been rendered ammoniacal and set aside.83 Ifmagnesium is also present the precipitate is crystalline and contain mag-nesium together with all of the titanium.The titanium in this precipitatecan then be determined in the usual fashion as the per-complex. Sulphatecan be determined indirectly by addition of excess of barium chloride anddetermination of the excess of barium.84 Fluoride can likewise be deter-64 K. L. Cheng, s. W. Melsted, and R. H. Bray, Soil Sci., 1953, 75, 37.65 W. A. Forster, Analyst, 1953, 78, 179.6 6 E.G. Brown and T. J. Hayes, Analyt. Chiw. Acta, 1953, 9, 1.68 F. E. Faller, 2. anal. Chem., 1953, 139, 15.69 D. Pickles and C. C. Washbrook, Analyst, 1953, 78, 304.70 N. Straiford, ibid., p. 733.72 K. Ter Haar and J. Bazen, Analyt. Chim. Acta, 1953, 9, 235.7 3 13. Flaschka, K. Ter Haar, and J. Bazen, Mikrochim. Acta, 1953, 346.74 H. Flaschka and F. Huditz, 2. anal. Chem., 1952-1953, 137, 172.75 H. Flaschka and A. M. Amin, Mikrochim. Acta, 1953, 414.76 W. Pilz, Moflatsh., 1952, 83, 1291.7 7 H. Flaschka and A. M. Amin, Mikrochim. Acba, 1953, 410.7 8 Idem, 2. anal. Chew., 1953, 139, 6.79 D. Lydersen and 0. Gjems, zbid., 138, 249.8o K. L. Cheng, R. H..Bray, and T. Kurtz, Analyt. Chem., 1953, 25, 347.A. L. Underwood, zbzd., p. 1910.82 P. B.Sweetser and C. E. Bricker, ibid., p. 253.83 W. F. Pickering, Analyt. Chim. Acta, 1953, 9, 324.K. E. Langford, Electroplating, 1953, 6, 41, 68.Idem, ibid., p. 6.71 H. Flaschka, 2. anal. Ckem., 1953, 138, 332342 ANALYTICAL CHEMISTRY.mined by precipitation with excess of standard calcium chloride solution. 85Tungsten can be determined by precipitation as calcium tungstate, solutionof the precipitate, and decomposition to give calcium chloride and tungsticacid. After removal of the latter the filtrate containing calcium equivalentto the tungsten is titrated.86 Palladium is determined through thenickel equivalent liberated on addition to a solution of complex nickelcyanide. 87Ethylenediaminetetra-acetic acid has been used to prevent interferenceof other metals in the determination of copper by diethyldithiocarbamate.88~ 89The polarography of solutions of ethylenediaminetetra-acetic acid con-taining copperJgO mercuryJgl and vanadiumg2 has been studied, and it issuggested that the indirect determination of calcium, magnesium , and ironthrough the waves given by anodic depolarisation should be possible.93 Theabsorption spectra of complexes formed with chromium have been relatedto pH.94The separation of lanthanon mixtures into enriched fractionsJg5 basedon the considerable differences in stabilities of the complexes with ethylene-diaminetetra-acetic acid 96 and the consequent separation on an ion-exchangecolumn, has been reported.For separation of certain lanthanon pairs onion-exchange columns it is pointed out that the most efficient pH rangecannot be used to advantage because of the low solubility in this range.97Fractionation using the method of precipitation in homogeneous solutionhas achieved preferential precipitation of the lanthanons of lower atomicnumber by complexing of the o x a l a t e ~ .~ ~ This arises from the fact that,although the solubilities of the oxalates decrease with increasing atomicnumber, the stabilities of the ethylenediaminetetra-acetic acid complexesincrease. These separations, which are in the reverse order from thoseachieved by normal methods, are comparable with them in efficiency.The copper complex in alkaline solution is foundg9 to behave in rathersimilar fashion to Benedict’s solution in the qualitative test for reducingsugars.Although it has been found that ethylenediaminetetra-acetic acid alonegives a poor separation of iron and manganese before the determination ofniobium and tantalum,lOO yet when the reagent is mixed with chelatingagents of the iminodiacetic acid type (not more fully formulated) muchbetter separations, capable of being usefully employed analytically, areachieved.The ethylenediamine-di- and -tetra-propionic acids have also been85 R.Belcher and S. J. Clark, Analyt. Chim. A d a , 1953, 8, 222.8 6 A. de Sousa, ibid., 9, 309.K. L. Cheng and R. H. Bray, Analyt. Chem., 1953, 25, 655.89 A. Jewsbury, Analyst, 1953, 78, 363; W. A. Forster, ibid., p. 614.R. L. Pecsok, Analyt. Chem., 1953, 25, 561.91 J.Goffart, G. Michel, and G. Duyckaerts, Analyt. Chim. Ada, 1953, 9, 184.92 R. L. Pecsok and R. S. Juvet, J . Amer. Chem. Soc., 1953, 75, 1202.93 D. Lydersen, 2. anal. Chem., 1953, 139, 327.9 4 R. E. Hamm, J . Amer. Chem. Soc., 1953, 75, 5670.O 5 E. J. Wheelwright and F. H. Spedding, ibid., p. 2529.O 6 E. J. Wheelwright, F. H. Spedding, and G. Schwarzenbach, ibid., p. 4196.9 7 S. W. Mayer and E. C. Freiling, ibid., p. 5647.9 8 L. Gordon and K. J. Shaver, Analyt. Claem., 1953, 25, 784.99 13. Wagreich and B. Harrow, ibid., p. 1925.loo C. F. Hiskey and ,4. L. Batik, ibid., p. 823.87 H. Flaschka, Mikrochim. Acta, 1953, 226WILSON INORGANIC QUALITATIVE ANALYSIS. 343studied,lol and complexing is found to occur less effectively on replacementof acetate by propionate.The acid dissociation constants of nitrilotri-carboxylic acids, compounds which have many similarities in action toethylenediaminetetra-acetic acid, have been measured. lo2Of certain p-diketones investigated for the extraction of zirconium andhafnium from perchloric acid solution, benzene solutions of 2-thenoyltri-fluoroacetone and 2-furoyltrifluoroacetone have been found lo3 to be themost satisfactory, and the former is stated to be preferable since the diketonehas a more satisfactory partition coefficient.3. INORGANIC QUALITATIVE ANALYSIS.The classical scheme, using hydrogen sulphide, for the semimicro-analysis of cations has been extended to include all the elements likely to bemet with in modern analytical practice.104 An apparatus has been describedfor the passage of gas into small volumes of liquid down to one drop.lo5 Amodified scheme of analysis has been devised which utilises precipitationof thio-salts of elements of the arsenic group and vanadium on addition ofammonium sulphide, these compounds being subsequently decomposed tosulphides on treatment with hydrochloric acid.lo6 The method is claimedto be preferable to the use of hydrogen sulphide, and the scheme includessome of the less familiar elements.An aqueous-ethanolic solution of p-naphthyl sulphide has been recom-mended as a reagent for certain heavy metals.107 A.Sykes has reviewedthe precipitation of sulphides by reagents other than hydrogen sulphide.lo8A systematic analysis of the cations is based on basic benzoate andfluoride precipitations, and eliminates the normal sulphide separation.logh i o i i s can be separated into seven groups and identified within the groupsby specific tests by utilising the insolubility of the salts of lithium, calcium,barium, zinc, and lead.l1°E.Dannenberg ll1 has recommended the impregnation of appropriatecarriers such as paper and silica granules with an extensive series of thereagents required in inorganic analysis. In this way small volumes ofsolution may be analysed reliably and with economy. A number of tests forthe identification by fluorescence of ammonium, potassium, sodium, iron,and cadmium ions have been described. 112 Electrographic methods ofanalysis have been reviewed briefly 113 and their use in the identification ofalloys has been described.ll* Electrolytic methods of detection on theultramicro-scale may be employed for the detection of g.ina volume of ml.115toIo1 R. C. Courtney, S. Chaberek, andA. E. Martell, J . Amer. Chem. Soc., 1953, 75, 4814.lo2 S. Chaberek and A. E. Martell, ibid., p. 2888.lo3 E. M. Larsen and G. Terrey, ibid., p. 1560.lo4 H. Holness and K. R. Lawrence, Analyst, 1953, 78, 356.lo5 H. Weisz, Mikrochim. Acta, 1953, 14.lo6 I. K. Taimni and R. P. Agarwal, A9zaZyt. Chim. A d a , 1953, 9, 208.lo7 J. W. Airan and D. S. Wagle, Curr. Sci., 1953, 21, 339.log Ind. Chem. Chem. Manuf.., 1953, 29, 201, 256.log P. W. West, M. M. Vick, and A. L. LeRosen, “ Qualitative Analysis and Analyti-110 C. Malen and P.B6villard, Analyt. Chim. Acta, 1953, 8, 493.113 P. R. Monk, Analyst, 1953, 78, 141.115 I. P. Alimarin and M. N. Petrikova, J . Anal. Chem., U.S.S.R., 1953, 8, 11.cal Separations,” New York, 1953.Ibid., p. 310. I<. P. Stolyarov, J . Anal. Chem. U.S.S.R., 1952, 7, 195.114 G. C. Clarkand E. E. Hale, ibid., p. 145344 ANALYTICAL CHEMISTRY.M. Kohn 116 has examined the coloration by several transition elementsof melted polyphosphates, and on the basis of his examination has proposedmechanisms for the well-known microcosmic salt bead test.A colour reaction for fluoride in the presence of a number of interferingions is carried out with titanium and chromotropic acid on Cel10phane.l~~Hydrazine can be detected on filter-paper by condensation with ?-dimethyl-aminobenzaldehyde to give a coloured product which is adsorbed practicallyirreversibly, although water-soluble.ll* Nitrite can be distinguished fromnitrate by its reaction with 2-amino-4-chloromethylthiazole hydrochl~ride.~~~Instead of the usual Griess-Ilosvay test, the product from the diazotisationof sulphanilic acid can be coupled with cc-naphthol to give a sensitive test.lZ0If nitrate is reduced by means of zinc dust within a narrow pH range (4-5),and the excess of zinc dust is removed, the test can also be applied to this ion.Tellurium in lead-tellurium alloys is dissolved, and precipitated from solution by stannouschloride as colloidal element.122 Germanium can be identified by phenyl-fluorone.121 R.J. Winterton 123 has studied sodium cobaltithiosulphate,sodium calcium ferrocyanide, and sodium uranyl chromate as reagents forpotassium as compared with the more usual sodium cobaltinitrite.Thesensitivities are found to be poor in comparison, but the first and third ofthese reagents may have some use for the detection of potassium in thepresence of ammonium ion. The separation of calcium and strontium byconcentrated nitric acid has been found satisfactory on the semimicro-~ca1e.l~~Beryllium can readily be identified in minerals by the test with quina1i~arin.l~~The test for zinc by precipitation as the double mercury thiocyanate in thepresence of small amounts of cobalt is improved if small amounts of nickelare added in addition to the cobalt.lZ6 If zinc is not present the presenceof the nickel delays the precipitation of cobalt mercuric thiocyanate, prevent-ing any possibility of a misleading resdt.Morpholine has been recom-mended for the detection of cadmium.127 The palladous chloride test formercury has been rendered more sensitive by first collecting the mercuryvapour on gold leaf.128 A procedure has been described for the separationand identification of mercury in systematic analysis on microgram samples.12’The mercurous ion has been identified by reduction of iron(II1) in the presenceof thiocyanate, the iron(11) ion produced being then identified by suitablereagents such as 1 : lO-phenanthr~Iine.~~~The reactions involved in the complexing of copper in ammoniacalsolution by the addition of sodium cyanide have been examined.131 Alizarin-Selenium can be detected by diaminobenzidine.116 Analyt.Chim. Acta, 1953, 9, 226.117 A. K. Babko and P. V. Khodulina, J . Anal. Chem., U.S.S.R., 1952, 7, 281.118 F. Feigl and W. A. Mannheimer, Mikrochem. Mikrochim. Acta, 1952-1 953,40,355.l 1 9 A. L. Misra, R. C. Mehrotra, and J. D. Tewari, 2. anal. Chem., 1953, 139, 89.120 P. Woodward, Analyst, 1953, 78, 727.121 J. Gillis, Analyt. Chim. Acta, 1953, 8, 97.122 E. G. Brown, Analyst, 1953, 78, 623.124 R. B. Hahn, J . Chevn. Educ., 1953, 30, 349.125 F. Feigl and L. Baumfeld, Anal. Assoc. quim. B r a d , 1951, 10, 13.lZ6 F. E. Brown and J. S. Proctor, Analyt. Chem., 1953, 25, 1122.12’ M. V. Rodina, J . Anal. Chem., U.S.S.R., 1952, 7, 312.128 G.Sachs, Analyst, 1953, 78, 185.129 H. M. El-Badry and C. L. Wilson, Mikrochem. Mikrochim. Acta, 1952-1953, 40,131 R. K. McAIpine, Analyt. Chem., 1953, 25, 331.la3 Analyt. Chim. Acta, 1953, 8, 1.218. 130 F. Lucena-Conde, Anal. Soc. es$. Fis. Quim., 1953, 49, B, 45WILSON : INORGANIC GRAVIMETRIC ANALYSIS. 345blue 132 and o-hydroxyphenylfluorone l 2 l have been recommended as reagentsfor the detection of copper. Silver has been separated and identified on themicrogram scale.129 Diphenyl phosphate has been used for the identificationof aluminium 133 and 2 : 5-dihydroxy-1 : 4-benzoquinone for the identi-fication of scandium.l3* The lanthanons can be detected as a group byusing o-arsenobenzeneazo-Z’-l‘ : 8’-dihydroxynaphthalene-3’ : 6’-disulphonicacid l35 and tests for individual members of the group have been described.136Thallium thiourea perchlorate crystals can be used to identify thalliumunder the microscope in the presence of considerable excess of many otherelements, including lead.137 By a suitable procedure interfering ions canbe removed, allowing iron to be identified by S-hydroxyq~inoline.~~~ Analmost specific coloration is given by iron with the dye 5-3’-carboxy-2’-hydroxy-1 ’-methylazobenzeiie-4-sulphonic acid, only palladium and uraniumgiving similar reactions.139 Diphenyl phosphate gives a very sensitivereaction with iron.133 Cobalt can be detected as the green peroxy-complexformed in the presence of sodium hydrogen carbonate 140 or as the char-acteristic crystalline precipitate formed with hydro~yiminodirnedone.~~~An acetone solution of diphenylglyoxime has been recommended 142 for thedetection of nickel. Molybdenum can be detected by the decolorisation ofmethylene-bl~e,~~~ by the red complex formed with gossyp01,l~~ or by thereaction with o-hydroxyphenylfluorone.Ul Tungsten has been separatedon the microgram scale,129 and can be identified with ammonium thiocyanate,st annous chloride, and ammonium bifluoride.145 8-H ydroxyquinoline canbe applied as a field test for uranium.146 Tin can be detected by the fluor-escence given with 6-nitro-2-naphthylamine-8-sulphonic acid. 14’ The separ-ation and identification of lead on the microgram scale has been d e s ~ r i b e d . ~ ~The test for titanium with diphenyl phosphate is stated to be particularlysensitive, so that after precipitation it is impossible to detect titanium in theresidual solution by the usual peroxide test.133 Bismuth can be detectedeither by morpholine and potassium iodide or by diphenyl ~ h 0 s p h a t e .l ~ ~4. INORGANIC GRAVIMETRIC ANALYSIS.A quartz-fibre microbalance has been adapted to carry light absorptiontubes and other relatively bulky objects.148 It is claimed that it will carrya 5-g. load and will give a reproducibility of & 0.26 pg. when carrying aplatinum boat weighing 0-4 g. Special attention has been paid to vibration-free mounting and it is proposed to use the balance for organic analyses inF. Feigl and A. Caldas, Analyt. Chirn. Acta, 1953, 8, 117.133 F. Knotz, Anal.SOC. esp. Fis. Quim., 1952, 48, B , 564.134 L. Pokras and &I. Kilpatrick, AnaZyt. Chenz., 1953, 25, 1270.135 V. I. Kuznetsov, J . Anal. Chem., U.S.S.R., 1952, 7, 226.136 L. M. Kulberg and M. N. Ambrozhy, ibid., p. 233.l37 C. Mahr and H. Klamberg, Mikrochem. Mikrochtim. Actu, 1952-1953, 40, 390.138 A. de Sousa, ibid., p. 265.140 A. de Sousa, Mikrochem. Mikrochim. Acta, 1952-1953, 40, 352.141 J. Gillis, J. Hoste. and J. Pijck, Mikrochim. Acta, 1953, 244.142 W. Wawrzynek, Roczn. Chem., 1952, 26, 668.la3 F. Feigl and L. Baumfeld, Anal. Assoc. quim. B r a d , 1951, 10, 14.144 A. Vioque-Pizarro and H. Malissa, Mikrochem. Mikrochim. Acta, 1952-1 953, 40,145 R. Vanossi, Anal. Asoc. quim., Argent., 1952, 40, 176.l4O A. de Sousa, Mikrochem. Mikrochim.Acta, 1952-1953, 40, 319.147 J. R. A. Anderson and J. L. Garnett, Amzlyt. Chim. Actu, 1963, 8, 393.148 J. A. Kuck, P. L. Altieri, and A. K. Towne, Mikrochim. Acta, 1953, 254.130 C. Ott, Ann. Chim. analyt., 1953, 35, 149.396346 ANALYTICAL CHEMISTRY.the ultramicro-range (< g.). A differential thermobalance has beendescribed which carries two exactly similar samples held at temperatures4” apart.149 It gives a direct photographic record of the change of masswith temperature, registered as a function of time and therefore as a functionof temperature. The mode of use of the Chevenard thermobalance, andresults obtained from it in an extensive series of studies of substances ofanalytical interest, have been published in book form.150 A statisticalinvestigation of the use of the ordinary microchemical balance has shownthat the estimation of fractional divisions on the balance scale is subject toindividual preference to such an extent that errors of up to 0.25% may beintroduced into the ordinary carbon and hydrogen determination.l51 A.-G.Loscalzo and A.A. Benedetti-Pichler 152 have checked Gauss’s double-weighing method against single-weighing technique, both for a standardanalytical balance and for a microchemical balance, and have confirmed thatthe precision is approximately doubled by using the former method.G. Kainz 153 has described a micro-filter which uses a coarse layer ofmaterial such as cotton wool or sea sand as a pre-filtering layer, followedby a fine layer of cellulose powder or asbestos which because of the protectionremains intact for many filtrations. Crucibles for microchemical analysishave been standardised.154 A investigation of the behaviour of titanium,vanadium, and zirconium towards fusion reagents suggests that crucibles ofzirconium might be very satisfactory for sodium hydroxide f u ~ i 0 n s . l ~ ~Precipitation in Homogeneous Solution.-Unexpectedly little fresh workutilising this method appears to have been done. Aluminium, when pre-cipitated in homogeneous solution as the 8-hydroxyquinoline complex, bythe hydrolysis of urea, gives a precipitate of excellent analytical q ~ a 1 i t y . l ~ ~Co-precipitation of iron, manganese, and nickel are found to interfere withthe precipitation of tin from a sulphate solution by hydrolysis of urea.157Also, although the precipitate is excellent in character, it appears to be thebasic sulphate rather than the basic oxide, and cannot be used directly fordetermination of tin.Lead can be determined as sulphate by the hydrolysisof dimethyl s ~ 1 p h a t e . l ~ ~ If barium-radium mixtures are fractionally pre-cipit ated from homogeneous solution as chromates, radium is found concen-trated in the ~rysta1s.l~~ Two ingenious methods suggest that the principleof precipitation in homogeneous solution is capable of very considerableextension through intelligent use of reactions previously considered to berelatively unimportant from the analytical standpcjint. In the first of thesecerium is separated from the other lanthanons by oxidation in the presenceof potassium iodate, by using persulphate, from cei-ium(m), whose iodate issoluble, to cerium(1v) whose iodate is insoluble.160 Thorium iodate is normallymost unsatisfactory as an analytical precipitate, since it is exceedingly149 W.L. De P y s e r , Nature, 1953, 172, 364.1x1 C. Duval,151 H. Gysel, Mikrochim. Acta, 1953, 266.lS2 Mikrochem. Mikrochim. Acta, 1952-1953, 40, 232.153 Microchim. Acta, 1953, 119.155 R. S. Young and K. G. A. Straclian, Chewz. and Ind., 1953, 154.156 K. E. Stumpf, 2. anal. Chem., 1953, 138, 30.15‘ H. H. Willard and L. Gordon, Analyt. Chew., 1953, 25, 170.158 P. J. Elving and W. C. Zook, ibid., p. 502.lS9 M. L. Salutsky, J. G. Stites, and A. W. Martin, ibid., p.1677.le0 H. H. Willard and S. T. Yu, ibid., p. 1754.Inorganic Thermogravimetric Analysis,” London, 1953.1 5 4 B.S.I. Specif., 1953, No. 1428, Pt. E 1LVILSON : INORGANIC GRAVIMETRIC ANALYSIS. 347gelatinous and difficult to manipulate. An excellent form of precipitate is,however, achieved if the iodate is precipitated in homogeneous solution,either by oxidation of iodide, or preferably by reduction of periodate.161In the latter case 2-hydroxyethyl acetate is hydrolysed to ethylene glycol;this in turn reduces the periodate to iodate. The precipitate of thoriumiodate is dense and granular, and a double precipitation by this methodgives quantitative separation from large amounts of lanthanons and phos-phate. Co-precipitation in homogeneous solution of manganese with basicstannic sulphate and of strontium with barium sulphate have been studied.162Methods of Analysis.-Arsenic has been precipitated as the thio-salt andconverted into sulphide by 164 The nature of barium sulphateprecipitates produced under varying conditions has been studied by lightand electron-microscopic examination, 165 and on the basis of this examin-ation a rapid method has been proposed for the determination of sulphate.Adsorption on barium sulphate precipitates has also been studied byX-ray methods.166 The thermogravimetric curve for the decomposition ofocta-ammino-p-ammino-p-nitrodicobaltic sulphate has been determined.167Selenium has been determined as mercuric selenite,lG8 or as the element, pre-cipit ated by reduction with sulphur dioxide in hydrochloric-perchloric acids01ution.l~~ This method is also applicable to the determination of tellurium.Selenium and tellurium have also been determined as sulphides through thethi0-sa1ts.l~~ The precipitation of silica as the complex quinoline silicoinolyb-date has been utilised satisfactorily,170 but the complex formed with 2 : 4-di-methylquinoline is stated to be slightly hygroscopic and, rather than weigh-ing it directly, it is preferable to convert it into the anhydride by ignition at500-560".171 Germanium is precipitated by o-dihydro~yphenols.~~~ Avery satisfactory factor is given by precipitation as barium germaniumtartrate 173 and the determination by this method can be carried out evenin the presence of a considerable amount of arsenite.Radiochemical methods have been used to investigate the best conditionsfor the precipitation of potassium, rubidium, and czsium as the tetraphenyl-boron and a method has been described 175 for the determin-ation of potassium and ammonkm together by precipitation of both ions asthe tetraphenylboron compounds and subsequent extraction of the ammon-ium salt by alkaline acetone, in which the potassium compound is insoluble.Potassium has also been precipitated as the 1Qphosphomolybdate 17G or as161 C.R. Stine and L. Gordon, Analyt. Chem., 1953, 25, 1519.162 L. Gordon, C. C. Reimer, and H. Teicher, ibid., p. 838.163 I. K. Taimni and R. P. Agarwal, Analyt. Chim. Ada, 1953, 9, 116.164 Idem, ibid., p.121.165 R. B. Fischer and T. B. Rhinehammer, Analyt. Chem., 1953, 25, 1544.C. A. Streuli, H. A. Scheraga, and M. L. Nichols, ibid., p. 306.167 D. Gibbons, J., 1953, 1641.168 G. S. Deshmukh and K. M. Sankaranarayanan, J . Indian Chem. SOC., 1952, 29,527.169 H. Got6 and Y . Kahita, Sci. Rep. Res. Inst. TGhoku Univ., 1952, 4, 28; H. Got6171 C. C. Miller and R. A. Chalmers, Analyst, 1953, 78, 24.172 P. Bkvillard, Comfit. rend., 1952, 234, 216.173 G. N. Schrauzer, Mikrochim. Acta, 1953, 124.17* W. Geilmann and W. Gebauhr, 2. anal. Chew., 1953, 139, 162.175 hl. Kohler, i b i d . , 1953, 138, 9.1 7 6 R. Belcher and J. W. Robinson, A.tzaZyt. Chinz. Acta, 1953, 8, 239.and T. Ogawa, ibid., p. 121.M. Armand and J. Berthoux, Analyt. Chim. Acta, 1953, 8, 510348 ANALYTICAL CHEMISTRY.a precipitate with the definite composition K3[Co(N0&] ,2H,O, formed byprecipitation with lithium cobaltinitrite.177 Caution is advised in the useof alcoholic solutions of reagents in the determination of sodium by tripleacetate formation since the formula of the precipitate is rendered even moreuncertain through variable replacement of water molecules by alcoholrn0lecu1es.l~~ Sodium can be determined as the triple acetate in potassiumsalts if the potassium is first precipitated as perchlorate and filteredLithium can be precipitated as trilithium phosphate by using choline phos-phate in isopropanol as reagent.lsO Anhydrous calcium oxalate is notrecommended as a weighing form since it is sufficiently hygroscopic to revertslowly to the monohydrate.lS1 The gravimetric determination of stron-tium l*2 and of barium 183 as oxalates has been investigated. Zinc is pre-cipitated by 5 : 6-benzoquinaldinic acid as the compound Zn(C,,H8N0,)2,H,0which may be dried a t 110-115" and weighed.184 The corresponding cad-mium compound contains 1.5 molecules of water, but is anhydrous a t 125-130°, so that drying a t a temperature somewhat above this enables theelement to be determined.ls5 Zinc and cadmium can be separated byutilising the precipitation of cadmium metal from a solution containingpotassium cyanide and potassium sodium tartrate by metallic copperprepared by reduction of copper oxide.ls6 In these conditions zinc is notprecipitated. A complex bromide is formed by cadmium in the presenceof potassium bromide with diantipyrinyl-o-hydro~ypheny1methane.l~~Mercury can be determined as the complex with Z-o-hydroxyphenylbenz-iminazole.Alizarin-blue 189 and the sodium salt of N-(N-bromo-C-tetradecyl-bet ainy1)-C-tetradecylbetaine lS0 have been recommended for the gravimetricdetermination of gold.This element has been separated from platinum-metal mixtures and determined by quin01.l~~In the analysis of silicate rocks, aluminium has finally been determinedas 8-hydroxyquinoline complex after extraction together with beryllium byusing acetylacetone.lQ2 Other interfering elements are first extracted as thecupferron complexes by using o-dichlorobenzene. Means of reducing errorsdue to co-precipitation in the determination of gallium by cupferron havebeen recommended.lQ3 The manganese complex of 5 : 6-benzoquinaldinicacid 184 has the formula Mn(C,,H8N0,),,2.5H,0. A reagent for ironwhich is a t least as sensitive as the naphthyl analogue of cupferron177 T. Dupuis, Analyt. Chim. Acta., 1953 9, 493.L. B. Rogers and G. P. Haight, ibid., 1952, 7 , 501.179 C. Jackson, Analyst, 1953, 78, 599.180 E. R. Caley and G. A. Simmons, Analyt. Chem., 1953, 25, 1386.C. C. Miller, Analyst, 1953, 78, 186.T. Matsumoto, Bull. Chem. Soe. Japan, 1952, 25, 242.183 Idem, ibid., p. 361.184 A. K. Majumdar and A. K. De, J . Indian Chem. SOC., 1953, 30, 123.las Idem, ibid., 1952, 29, 499.A. Bryson and S . L. Lowy, Analyst, 1953, 78, 299.Is' V. I. Kumov, J .Anal. Chem., U.S.S.R., 1952, 7 , 301.l a 8 J. L. Walter and H. Freiser, Analyt. Chem., 1953, 25, 127.F. Feigl and A. Caldas, Analyt. Chim. Acta, 1953, 8, 339.loo A. E. Harvey and1 9 1 R. R. Barefoot and F. E. Beamish, ibid., 9, 49.Is* C. C. Miller and R. A. Chalmers, Analyst, 1953, 78, 686.loS E. Gastinger, 2. anal. Chem., 1953, 139, 1.. H. Yoe, Analyt. Chim. Acta, 1953, 8, 246WILSON INORGANIC GRAVIMETRIC ANALYSIS. 349(neocupferron) has been prepared by replacing the benzene nucleus in cup-ferron by the fluorene nucleus to give the 2-fluorenyl derivative.lg4 Di-antipyrinylphenylmethane gives a complex ferricyanide which may be usedfor the gravimetric determination of ferricyanide.lg5 Ferrocyanide does notreact. For the gravimetric determination of cobalt the complex with5 : 6-benzoquinaldinic acid, which has the formula Co (C,,H,02N),,2H 20,can be used.ls4 The corresponding nickel complex, like the manganese one,contains 2.5 molecules of water.Determination of nickel can be carriedout as accurately with resacetophenone oxime as with dimethyl-g l y o x i ~ x e . ~ ~ ~ ~ 197 A standard method for the determination of molybdenumin low-alloy steeIs has been pub1i~hed.l~~ Molybdenum can also be deter-mined as the sulphide, MoS3,2H,O, after precipitation as a t h i o - ~ a l t , ~ ~ ~ ? lD9or as the oxide after precipitation as sulphide in the normal fashion 2oo orby use of thiosulphate as precipitant .,O1 Treatment with thiofonnamideprecipitates tin as the anhydrous sulphide which can then be dried andweighed,,02 Tin, precipitated by ammonium sulphide as the thio-salt, canbe converted into the sulphide SnS2,2H20 for weighing; lg9 or it can beprecipitated from hydrochloric acid solution by N-benzoylphenylhydroxyl-amine as the complex chloride, which is then ignited and weighed as oxide,or is dried at 110" and weighed as (Cu,,HI,O,N),SnCl2, which has a muchmore favourable factor.203 Separations of zirconium with mandelic acid 204or with P-chloromandelic or $-bromomandelic acid 205 have been proposed.A study of the solubility of thorium oxalate under analytical conditionssuggests that this form is not suitable if other means of precipitation areavailable.,06 Reagents proposed for the gravimetric determination ofthorium include stearic, pyrogallic, and m-hydroxybenzoic acids 207 andvanillic acid.208 The thermogravimetric curve for dichlorobisethylene-diaminecobaltic hexachlorostibnate has been determined.167 Precipitationof antimony with thioformamide is preferred to precipitation with hydrogensulphide.202 The red modification of sulphide which is obtained in thisprecipitation is converted into the black modification for weighing. Bismuthhas been determined by benzidine in the presence of potassium iodide209or by trimethylphenylammonium iodide.2lO Direct combustion in oxygento the textroxide, absorption in potassium hydroxide, and weighing has beenutilised for the determination of osmium.211 Both thioglycollic-p-amino-naphthalide (thionalide) and 2-phenylbenzothiazole have been recom-lS4 R.E. Oesper and R. E. Fulmer, Analyt. Chem., 1953, 25, 908.1B5 S. I. Gusev and R. G. Beyles, J . Anal. Chem., U.S.S.R., 1952, 7, 219.lS6 K. S. Bhatki and M. B. Kabadi, J . Sci. Ind. Res. India, 1952, 11, B, 346.Is' Idem, ibid., 1953, 12, B, 226.lSs I. K. Taimni and R. P. Agarwal, Analyt. Chim. Acta, 1953, 9, 203.201 H. N. Rby, Analyst, 1953, 78, 217.202 A. Musil, E. Gagliardi, and K. Reischl, 2. anal. Chem., 1052-1953, 137, 252.203 D. E. Ryan and G. D. Lutwick, Canadian J . Chem., 1953, 31, 9.204 E. C. Mills and S. E. Hermon, Analyst, 1953, 78, 256.205 R. A. Papucci, D. M. Fleishman, and J. J. Klingenberg, Analyt. Cheutz., 1953, 25,206 H. L. Kall and L. Gordon, ibid., p. 1256.207 G. S. Deshnukh and J. Xavier, J .Indian Chern. Soc., 1952, 29, 911.208 K. V. S. Krishnamurty and A. Purishottam, Rec. Trav. chim., 1952, 71, 671.20s G. I. Barannikov, J . Anal. Chem., U.S.S.R., 1952, 7, 239.210 T. S. Burkhalter and J. F. Solarek, Amlyt. Chem., 1953, 25, 1125.211 A. ILlusil and R. Pietsch, Z. anal. Chem., 1952-1953, 137, 321.lo* B.S.I. Specif., 1952, 1121, Pt. 26.J. Ibarz Azn&rez and P. Mirb Plans, Anal. Soc. esp. Fis. Qztim., 1952, 48, B, 758.1758350 ANALYTICAL CHEMISTRY.mended 212 as organic reagents suitable for the gravimetric determination ofosmium, the latter being rather more rapid. Strychnine sulphate may alsobe used for the same purpose, although its use is not quite so straightforward.Platinum can be determined as sulphide through the thio-salt 163 or can beseparated from gold and palladium by reduction with zinc.lg1 In suchmixtures 191 or in mixtures of other platinum metals 213 palladium is deter-mined as the dimethylglyoxime precipitate.5. INORGANIC TITRIMETRIC ANALYSIS.K.F. Korner 214 has described a burette with interchangeable graduatedportions which can be used for either macro- or micro-titrations. An air-controlled and an oil-controlled micro-burette having the convenience of stop-cock control have been devised.215 The principle of supplying standard acidor alkali derived, by passage through an ion-exchange column, from a singlepotassium chloride solution, has been applied to simplified micro-burettes ofthe horizontal type.216 An apparatus has been described 217 which simplifiestitrations, such as that of Karl Fischer, which must be carried out in acontrolled atmosphere.K.F. Korner 218 has discussed the dependence of titration errors on thetitrating solutions, and has shown how errors arising from different methodsof analysis may be converted to comparable forms. It has been shown 219that over extremely wide variations of sulphuric acid concentration thepermanganate-oxalate titration has little or no dependence on the acidconcentration. Methods for standardising titanous solutions, particularlyin the presence of traces of iron, have been examined,220 and it is claimed thatfor most purposes standard titanous chloride is preferable to standardtitanous sulphate. Potassium metaperiodate 221-223 and iodine trichloridein hydrochloric acid224 have been applied to a wide variety of titrimetricdeterminations.It has been shown 225 that in the presence of thiocyanatethe greatly enhanced reducing power of metallic mercury can be appliedto the determination of iron and other ions; in particular, ferricyanide canbe quantitatively reduced to ferrocyanide, which can then be titrated withceric solution.J. E. Kunzler 226 has prepared absolute sulphuric acid for use as a primarystandard, and concludes that for a given amount of effort in its preparationa sulphuric acid standard is about ten times as accurate as any previouslyused. Of the various sulphuric acid standards which may be prepared,constant-boiling acid is proposed as that most generally useful. The thermalstability of potassium acid phthalate has been investigated,227 and it is212 I.Hoffman, J. E. Schweitzer, D. E. Ryan, and F. E. Beamish, Analyt. Chem.,1953, 25, 1091. 213 G. H. Ayres and E. W. Berg, ibid., p. 980.214 2. anal. Chem., 1953, 139, 99. U. L. Upson, Analyt. Chem., 1953, 25, 977.216 B. W. Grunbaum and P. L. Kirk, Mikrochem. Mikrochim. Acta, 1952-1 953,40,416.217 R. H. Prince, Analyst, 1953, 78, 607.219 R. C. Brasted, Analyt. Chem., 1953, 25, 673.220 J. J . Lamond, Analyt. Chim. Acta, 1953, 8, 217.221 B. Singh and A. Singh, J. Indian Chem. SOL., 1952, 29, 517.222 Idem, ibid., 1953, 30, 143.224 Y. A. Fialkov and F. E. Kagan, Ukr. Khim. Zhur., 1952, 18, 55.225 F. Burriel-Marti, F. Lucena-Conde, and S. Bolle-Taccheo, Analyt. Chim.A cta,226 Analyt. Chem., 1953, 25, 93.tL7 E. R. Caley and R. H. Brundin, ibid., p. 142.218 2. anal. Chem., 1953, 138, 111.223 Idem, Analyt. Chim. Acta, 1953, 9, 22.1953, 9, 293\VJI,SON : INORGANIC TITRIMETRIC ANALYSIS. 351recommended that a safe upper limit for drying this material before use asa primary standard is 135". G. F. Smith and D. H. Wilkins 228 recommend2 : 4 : 6-tri~itrobenzoic acid as a primary standard in acidimetry. It isa material with a high equivalent, is anhydrous and non-hygroscopic, andserves as its own indicator, although bromothymol-blue may be used formore precise work. It is easily soluble in water, and the reagent and itssolutions are stable on storage. Bariumthiosulphate monohydrate has been discussed 229 as a standard foriodometry.It has a high equivalent and definite composition, is easilyprepared and is highly accurate. On the other hand its solubility is low sothat it must either be used as solid or in very dilute solution ; and its thermalstability is poor, so that it must be dried below 40".Methods of Analysis-The Volhard halide titration has been improvedon the basis of theoretical consideration^.^^^ R. Belcher and R. Goulden 231have used a sparingly soluble iodate to react with chloride and liberate anequivalent amount of iodate ion. After filtration this can be titrated iodo-metrically, giving an amplification factor of 6. Mercuric, mercurous, andsilver iodates are all suitable for the purpose, giving good reproducibilityalthough the accuracy of the titration is not high.Sodium chlorite has beentitrated against standard arsenite in the presence of sodium hydrogencarbonate, osmic acid acting as catalyst .232 Chlorate and perchlorate canbe determined in the presence of one another by reduction of chlorate bymeans of stannous solution, and subsequent reduction of the perchlorate bythe same agent catalysed by molybdate.233 Elementary iodine can be deter-mined 234 by extraction with carbon tetrachloride, conversion into iodide byalkali, and titrimetric determination, with an amplification factor of 36 oreven of 216. The results are as satisfactory as those obtained by distillingthe iodine, and very much superior to those obtained by using active carbonto retain it."5 Special treatment is necessary to release fluorine from veget-able material for d e t e r m i n a t i ~ n , ~ ~ ~ since otherwise calcium may retainfluorine in a form which is non-distillable by the usual methods of determin-ation.Contrary to earlier reports, if the titration of lead chlorofluoride, inthe determination of fluoride by means of Volhard's procedure, is carriedout under proper conditions, there is no pronounced fading at the end-point,237 and any slight fading that may occur can be readily overcome bythe addition of a slight excess of thiocyanate. Elemental fluorine can betitrated against bromine dissolved in bromine trifluoride a t room temper-ature, the end-point being indicated by the disappearance of the brominecolour ; 238 this reaction can also be used to determine bromine or substancessuch as metals, oxides, and halides which yield bromine when treated withbromine trifluoride.It may safely be dried at 130".Analyt.Chim. Acta, 1953, 8, 209.22g W. M. MacNevin and 0. H. Kriege, Analyt. Chem., 1953, 25, 767.2s0 E. Schulek, E. Pungor, and J. Kkthelyi, Analyt. Chim. Acta, 1953, 8, 229.231 Mikrochim. Acta, 1953, 290.233 G. P. Haight, Analyt. Chern., 1953, 25, 642.234 H. Spitzy, H. Skrube, and F. S. Sadek, Mikrochim. Acta, 1953, 375.235 Idem, 2. anal. Chem., 1953, 139, 110.236 L. F. Remmert, T. D. Parks, A. M. Lawrence, and E. H. McBurney, Analyt.237 R. Belcher and P. I. Brewer, Analyt. Chim. Acta, 1953, 8, 235.238 T . Sheft, H. H. Hyman, and J . J. Katz, AiaalyZ.Chenz., 1953, 25, 1877.232 E. G. Brown, Analyt. Chim. Acta, 1952, 7, 494.Chem., 1953, 25, 450352 ANALYTICAL CHEMISTRY.In the determination of ammonia in the presence of hydrazine 239 thelatter may be destroyed by oxidation by iodic acid, bromine, or alkalinepermanganate, before the actual determination. Nitrite can be deter-mined 240 by addition of excess of standard bromine solution in the presenceof pyridine as catalyst, the excess then being determined iodometrically.Nitrate can be estimated in the presence of nitrite by use of ferrous sulphateas reagent,241 but special precautions must be taken to prevent oxidationof nitrite, and in any case an empirical correction must be applied. Whenalkali nitrates or nitrites are heated with formic acid at 550", they are con-verted quantitatively into the corresponding alkali carbonates, which arethen determined titrimetri~ally.~~2 Improved iodometric methods havebeen proposed for the phosphorous acids 243 and for arsenic.24a Arsenite canbe determined by standard chlorite with an osmic acid ~ a t a l y s t .2 ~ ~ In thedetermination of hydrogen peroxide by ceric solution the reactions appear tobe affected by the presence of perchlorate, which forms a stable peroxidecomplex.245 A phosphoric-phosphorous acid mixture has been recommendedfor the liberation of sulphide sulphur before iodometric determinati~n.~~~ Itis claimed,247 however, that although the results in the iodometric deter-mination have a high accuracy, the method has too low sensitivity for certainpurposes, and as an alternative a hypochlorite titration is recommended, anempirical factor being necessary. From a study of the solubilities of amines u l p h a t e ~ , ~ ~ ~ 4-amino-4'-chlorodiphenyl has been developed for the rapidand accurate alkalimetric determination of ~ u l p h a t e , ~ ~ ~ particularly whennitrate is also present.Instead of benzidine, 4 : 4'-diaminotolane has beenrecommended as a precipitating reagent for the titrimetric determination of~ulphate.2~~ Nitrate, chlorate, and a range of metal ions show no inter-ference, and interference from aluminium can be avoided by addition oftartaric acid. For very small amounts of sulphate it is claimed that pre-cipitation and removal of barium sulphate, conversion of excess of bariuminto barium chromate, and determination of the excess of chromate withferrous sulphate avoids errors inherent in the conventional barium sulphaterneth0d.2~~ W.G. Hunt 252 advocates removal of metallic ions in sulphatesolution by passage through an ion-exchange column, before precipitationof the sulphate with excess of barium solution and titration of the excesswith et hylenediaminet etra-acetic acid. Sulphat es, sulphit es, and t hio-sulphates can be determined in mixtures i~dornetrically.~~~ A titrimetricprocedure has been proposed for per~ulphate.2~~ Selenium has been239 W. Pugh and W. K. Heyns, Analyst, 1953, '98, 177.240 J. V. L. Longstaff and K. Singer, ibid., p. 491.241 C. L. Johnson, Analyt. Chem., 1953, 25, 1276.242 F.Feigl and A. Schaeffer, Analyt. Chim. Acta, 1952, 7 , 507.243 R. T. Jones and E. H. Swift, Analyt. Chem., 1953, 25, 1272.244 J. Haslam and N. T. Wilkinson, Analyst, 1953, 78, 390.245 S. Baer and G. Stein, J . , 1953, 3176.246 0. Horak, 2. anal. Chern., 1953, 139, 196.247 P. 0. Bethge, Analyt. Chim. Ada, 1953, 9, 129.248 R. Belcher, M. Kapel, and A. J. Nutten, ibid., 8, 122.24g R. Belcher, A. J. Nutten, and W. I. Stephen, J., 1953, 1334.250 R. Belcher, M. Kapel, and A. J. Nutten, Analyt. Chim. Acta, 1953, 8, 146.e51 W. Geilmann and G. Bretschneider, 2. anal. Chem., 1953, 139, 412.S63 J . Amer. Water Works Ass., 1953, 45, 535.25s R. I. Mamberto, Rev. Fac. Cienc. qulm., La Plata, 1949, 24, 69.254 I. M. Kolthoff and E. M. Carr, AnaZyt.Chem., 1953, 25, 298WILSON : INORGANIC TITRIMETRIC ANALYSIS. 353determined 255 by conversion into selenocyanide, treatment with bromineto give an equivalent amount of cyanogen bromide, and iodometric com-pletion of the determination. Aluminium is removed from aluminium-boron alloys by potassium hydroxide before determination of the boron bya mannitol titration.256 Where silver is present interference is firstprevented by addition of thiosulphate before proceeding with the usualfinish for boron.257Potassium can be determined by precipitation in the presence of organicsolvents as the hydrogen tartrate and titration with alkali.25s Severalmodifications of the titrimetric determination of potassium through thetetraphenylboron compound have been proposed.In the presence of aknown excess of sodium hydroxide the complex may be allowed to react withmercuric chloride ; each g.-atom of potassium liberates three moles ofhydrochloric acid, estimated by titration of the excess of hydr0xide.25~ Onheating a mixture of the ammonium and potassium tetraphenylboron com-plexes, the ammonium compound is volatilised and the potassium compoundis converted into potassium metaborate, which can then be determined bytitration with alkali.260 The precipitation in the presence of ammoniumradical is advocated since it reduces loss in washing and brings down aprecipitate more suitable for filtration. In a third modification the potas-sium is precipitated by excess of sodium tetraphenylboron, and the excess isin turn precipitated by excess standard silver solution.261 The silver remain-ing in solution is then determined by a Volhard titration.Sodium can bedetermined z62 by precipitation as the triple uranyl acetate, followed byreduction of the uranium(v1) to uranium(1v) by chromium(I1) solution. Theexcess of chromium(I1) is destroyed by atmospheric oxidation and theuranium is titrated with ammonium hexanitratocerate.Beryllium can be precipitated as beryllium ammonium arsenate, and thearsenate in the precipitate determined iod~metrically.~~~ Magnesium can beprecipitated as the ammonium phosphate, dissolved in acid, and the excessof acid determined.264The ferrocyanide titration of zinc has been examined critically and aprocedure recommended 265 using diphenylbenzidine as internal indicator.Zinc and cadmium can be precipitated as the basic carbonates266 whichare then determined alkalimetrically, or as the anthrani1ates,z67 which arethen treated with standard bromide-bromate solution and determined bythiosulphate.The precipitate obtained when a cadmium solution is treatedwith diantipyrinyl-o-hydroxyphenylmethane can be dissolved in aqueousethanol in the presence of potassium bromide and titrated with standardalkali, methyl-orange being the indicator.lS7 When mercury salts aretreated with alkali in the presence of aqueous acetone the oxide remains in2 6 5 E. Shulek and E. K6ros, 2. anal. Chem., 1953, 139, 20.256 E. Eipeltauer and G. Jangg, ibid., 138, 18.257 S. Z. Haider, Analyst, 1953, 78, 673.2 5 8 A.F. Ievinsh and Y. K. 0201, J . Anal. Chem., U.S.S.R., 1953, 8, 53.259 H. Flaschka, A. M. Amin, and A. Holasek, 2. anal. Chem., 1953, 138, 241.2-50 Idem, ibid., p. 161.262 P. Trinder, Analyst, 1953, 78,180.264 D. Bourdon, Ann. Chim. analyt., 1952. 34, 221.265 M. R. Richardson and A. Bryson, Analyst, 1953, 78, 291.2 6 6 M. M. Tillu, Analyt. Chim. Ada, 1953, 8, 337.2-57 C. Cimerman and M. Selzer, ibid., 9, 26.261 W. Riidorff and H. Zannier, ibid., 1953, 139, 1.263 R. Airoldi, Ann. Chim. a$pl., 1953, 43, 15.REP.-VOL. L 354 ANALYTICAL CHEMISTRY.solution, but subsequent treatment with either potassium iodide or sodiumthiosulphate releases an equivalent amount of alkali which can be titratedwith acid, phenolphthalein being the indicator.268Mercury and copper can be determined alkalimetrically, with cresol-phthalein as indicator.269 In the former case the colour change correspondsto the formation of HgO, and in the latter to formation of CuS04,3Cu(OH),.The titration of cuprous thiocyanate by iodate has been investigated as ameans of determining milligram and microgram amounts of copper.270 Thiselement can also be determined by titration with dithizone in a homo-geneous acetone-water solution.271 Silver can be determined by iodidetitration in the presence of ammonium acetate, bromophenol-blue beingused as an adsorption indicator,272 or o-dianisidinegold(II1) as an ordinaryindicat0r.~~3Europium can be determined in lanthanon mixtures by passing thesolution through a Jones reductor into excess of ferric chloride solution andtitration with standard dichromate solution.274 There is no interferencefrom samarium or ytterbium, which are not reduced by zinc.The titration of manganese with 8-hydroxyquinoline can be carried outsatisfactorily under certain condition~.~7~ The amount of cuprous iodidenecessary to prevent interference from high concentrations of sulphate inthe iodometric determination of iron has been determined.276 When nickelferricyanide is added to potassium ferrocyanide interchange takes place, andthe equivalent amount of potassium ferricyanide is formed.277 After filtra-tion the ferricyanide can be determined by thiosulphate, thus permittingindirect determination of ferrocyanide.Cobalt, precipitated as the anthr-anilate, can be determined iodometrically after treatment with bromate-bromide Nickel solutions can be titrated directly with alkali ;with cresolphthalein as indicator, the colour change takes place aftercomplete precipitation of the nickel hydroxide.269Tin can be determined by reduction with iron and potassium iodide,followed by titration with standard iodate solution.278 Zirconium can beprecipitated by oxalohydroxamic acid.279 The precipitate is dissolved indilute acid and warmed, oxalic acid and hydroxylamine being produced.The hydroxylamine can then be determined by addition of excess of titanoussolution and back titration with standard iron(m).Thorium can be deter-mined by direct titration with ethylenediaminetetra-acetic acid, alizarin-redS being used as internal indicator.280Titrimetric methods for the determination of antimony have beenreviewed.281 Antimony can be determined, after precipitation with thio-268 M.N. Das, Analyt. Chem., 1953, 25, 1406.269 G. Denk, 2. anal. Chem., 1953, 139, 103.270 K. Tantranon and B. B. Cunningham, Analyt. Chem., 1953, 25, 194.271 R. Delavault and R. Irish, Compt. rend., 1951, 233, 1614.2 i 2 G. Mannelli, Analyt. Chim. Acta, 1953, 9, 232.273 F. Sierra and F. Romojaro, Anal. SOC. esp. Fis. Quim., 1953, 39, B, 131.274 D. G. Foster and H. E. Kremers, AnaZyt. Chew., 1953, 25, 1921.2 7 j K. Neelakantam and K. Parthasarathi, Proc. Indian Acad. Sci., 1952, 36, A , 123.2 7 6 E. W. Hammock and E. H.Swift, Analyt. Chem., 1953, 25, 1113.277 M. Kohn, Analyt. Chinz. Acta, 1953, 8, 317.278 C. Cimerman and hi. Ariel, ibid., 9, 10.279 S. K. Dhar and A. K. Das Gupta, J . Sci. I n d . Res.. India, 1952, 11, B, 500.2so J. J..Fritz and J. J. Ford, Analyt. Chem., 1953, 25, 1640.281 D. Gibbons, Ind. Chem. Chena. Manzdf., 1953, 29, 363, 418WILSON CLASSICAL ORGANIC ANALYSIS. 355formamide, by solution in acid followed by any of the usual titrimetricprocedures.282 Vanadium@) can be reduced quantitatively to vanadium(1v)by citric acid, which at the same time complexes any copper present.283The vanadium(1v) can then be determined by titration with standardiodine. Standard titrimetric methods for vanadium in carbon and low-alloysteels 284 and in ferro-vanadium 285 have been published.Indicators and Related Topics.-The indicator properties of some phos-phorus and arsenic analogues of methyl-orange, ethyl-orange, and Congo-redhave been studied.286 A new universal indicator has been proposed.2s7For a wide variety of titrations 4-amino-4’-methoxydiphenylamine has beenrecommended as a reversible redox indicator.288 The substance is watersoluble; at pH 0 the redox potential is 0.690 volt, and at pH 6 it is 0.375 volt.Linear starch fraction dissolved in 10% acetic acid is stated to be stableand sensitive.289 Sulphonic acid blue B has been proposed as an adsorptionindicator for iodide titrations in strongly alkaline media.290 Reviews ofthe use of fluorescent indicators for acid-base titrations, and recommendedexamples, have been publi~hed.2~~3 292Siloxene has been applied as a chemiluminescent indicator in the chromatetitration of lead solutions.2g3A new and simplified approach to the theory of pH, particularly in itsapplications to analytical chemistry, has been discussed.294 The pH ofphosphate and citrate buffers when calcium ions are added has been shownto be markedly affected because of the formation of association products.2956.CLASSICAL ORGANIC ANALYSIS.General.-The present state and future development of spot-test analysisas applied to organic analysis for the identification of functional groups andcompounds has been discussed.lMethods of control necessary in the determination of melting point bymeans of the Kofler hot stage have been described.296 A.J. Llacer 297 hasdevised a semimicro-pycnometer with a content of 2.5 ml. which can beused in conjunction with a good analytical balance. A method for thedetermination of the molecular weights of aromatic hydrocarbons throughformation and analysis of the picrates has been proposed.298 Methods havebeen described for the isopiestic determination of molecular weights upon3-7 mg. samples 299 and 1 mg. samples.3002s2 A. Musil, E. Gagliardi, and K. Reischl, 2. anal. Chew., 1962-1953, 137, 252.z83 M. R. Verma, V. M. Bhuchar, and V. P. Singh, J . Sci. I n d . Hes., India, 1953, 12,z S 6 G. M. Kosolapoif and G. G. Priest, J . Amer. Cltem. SOC., 1953, 75, 4847.Z S 7 T. Kato, K. Yamane, and 2. Hagiwara, Tech. Rep. TGhokzt Univ., 1953, 17, 148.288 L.Erdey and A. Bodor, 2. anal. Chem., 1952-1953, 137, 410289 J. L. Lambert, Analyt. Chem., 1953, 25, 984.291 M. Heros, Ann. Chim. analyt., 1953, 35, 114.292 J. De Rlent, J . Chem. Educ., 1953, 30, 145.2Q3 F. Kenny and R. B. Kurtz, Analyt. Chem., 1953, 25, 1550.394 F. L. Hahn, Analyt. Chim. Acta, 1953, 8, 297; J. Eeckhout, ibid., 9, 197.295 C. W. Davies and B. E. Hoyle, J . , 1953, 4134.296 0. Rizzolli, Mikrochim. Acta, 1953, 401.297 Mikrochem. Mikrochim. Acta, 1952-1953, 40, 179. 298 F. Scheibl, ibid., p. 343.2y9 J. E. Morton, A. D. Campbell, and T. S. Ma, Analyst, 1953, 78, 722.SO0 C. J. van Nieu.vyenburg and J. W. L. van Ligten, Analyt. Chim. Acta, 1953, 9, 66.B, 227. 284 B.S.I. Specif., 1952, 1121, Pt. 27. 285 Ibid., Pt.25.G. Mannelli and M. L. Rossi, Analyt. Chim. Acta, 1953, 9, 44356 ANALYTICAL. CHEMISTRY.Qualitative.-Existing methods for the detection of oxygen in organiccompounds have been examined, and a new method based on thermaldecomposition of the sample in a platinum contact in a stream of nitrogen,with detection of the resulting carbon monoxide, has been proposed.301Alkylene dihalides may be identified by reaction with 2-mercapto-6-nitro-ben~othiazole.~~~ Characteristic colours are produced in the reactionsbetween aliphatic alcohols and certain hydroxyaldehydes in the presenceof sulphuric acid.303 Glycols and their derivatives can be identified throughthe physical constants of the glycols together with the physical constants oftheir pseudo-saccharin ethers.304 The esters of phenols can be distinguishedfrom those of acids through the solubility of the potassium salts of thephenols in absolute methanoL305 A critical examination has been made ofthe 2 : 4-dinitrophenylhydrazones of carbonyl compounds in order to reachan explanation of some of the discrepancies in the literature regarding thesecompounds.306 Met hoxy- and ethoxy-carbonylhydrazones have been pro-posed as suitable for the identification of carbonyl compounds.307 Conden-sation of 1 : 4-diketones with p-nitroaniline gives derivatives which arepreferable for identification purposes to o x i m e ~ .~ ~ ~ Sugars give a specificcolour reaction with aminoguanidine followed by dichromate-sulphuric acidsolution.309 The eutectic fusion temperature and refractive index togetherare proposed as a means of identifying small amounts of arnin~-acids.~~O-~~~Alkaloids can be identified by determining the melting-points of theirprecipitates with sodium tetraphenylboron or with nitro-compounds, and ofthe eutectics with two or three standard substances.313Quantitative.-Recent developments in quantitative organic micro-analysis have been comprehensively re~iewed.~l4High-temperature furnaces prepared with an aluminium-chromium-cobalt wire winding have been worked up to 1250", and for short periods ateven higher temperatures.315 Specifications have been drawn up forcombustion boats and related apparatus.316G.F. Smith317 has made an investigation of the wet ashing of organicmaterial with perchloric acid, and has described conditions for carrying thisout with complete safety.By this method carbonaceous material is quantit-atively converted into carbon dioxide, but phosphorus, sulphur, and mineralconstituents are completely retained.W. Kirsten recommends polytetrafluoroethyIene joint links betweencombustion tube and absorption tube in the carbon and hydrogen deter-301 J. Goerdeler and €€, Domgorgen, Mikrochem. Mikrocieirn. Acta, 1952-1953,40,212.302 H. B. Cutter and A. Kreuchunas, Analyt. Chem., 1953, 25, 198.303 L. Rosenthaler and G. Vegezzi, Mitt. Lebensmitt.- Untersuch. Hyg., 1952, 43, 370.304 H. Bohme and H. Opfer, 2. anal. Chem., 1953, 139, 255.305 G. Carbone, J . Chem. Educ., 1953, 30, 315.306 L. I. Braddock, K.Y . Garlow, L. I. Grim, A. F. Kirkpatrick, S. W. Pease, A. J.Pollard, E. F. Price, T. L. Reissmann, H. A. Rose, and M. L. Willard, Analyt. Chern.,1953, 25,301. 307 N.Rabjohn and H. D. Barnstorff, J . Amer. Chem. SOC., 1963, 75,2259.308 M. Fetizon and P. Baranger, Compt. rend., 1953, 236, 1428.309 H. Tauber, Analyt. Chem., 1953, 25, 826.310 A. Lacourt, G. Sommereyns, C. Francotte, and N. Delande, Nature, 1953,172,906.311 Idem, Mikrochim. Acta, 1953, 306.313 R. Fischer and M. S. Karawia, ibid., p. 366.514 W. Kirsten, Analyt. Chem., 1953, 25, 74; R. Ldvy, Bull. SOC. chim., 1952, 19, 672.315 W. Kirsten, Analyt. Chem., 1953, 25, 805.316 B.S.I. Specif., 1953, No. 1428, Pt. I, 1. 317 Analyt. Cbim. Acta, 1953, 8, 397.312 G. Sommereyns, ibid., p.332WILSON : CLASSICAL ORGANIC ANALYSIS. 357minati0n.3~~ Apparatus has been described for the automatic micro-determination of carbon and hydrogen according to the Pregl-Zimmermanmethod but with use of manganese dioxide instead of lead dioxide.319The methods proposed for the direct determination of oxygen have beenexamined by an inter-laboratory panel, and four modifications of the Unter-zaucher procedure have been found to give results of reasonable accuracy,a11 of these methods taking pains to avoid the effect of pyrolytic hydrogen onthe iodine pent~xide.~*O E. G. Adams and N. T. Simmons report 321 thatthe iodine pentoxide used in the direct determination of oxygen must be asfree as possible from potassium, which lowers the reactivity.A semi-micro-method for the determination of oxygen is based on carbon reductionand determination of the carbon dioxide produced.322The Dumas-Pregl and Kjeldahl methods for determining nitrogen havebeen compared experiment ally.323 A modified all-glass apparatus forKjeldahl nitrogen in which digestion and distillation are carried out in asingle flask has been described.324 C. H. Perrin325 has advocated the useof sulphuric acid-mercuric oxide-pot assium sulphate for the digestion.P. R. W. Baker 326 has examined the effect of addition of selenium in sealed-tube digestions, and has found that it lowers the temperature of decom-position of ammonia by about 50". Reduction has been suggested as thelogical means of decomposing nitrogenous compounds before the Kj eldahldetermination of the nitrogen.M. Marzadro 327 has examined the selectiveeffect of the Kjeldahl method as applied to different types of nitrogen com-pounds, particularly heterocyclics. Investigation of the reactions takingplace in the Dumas determination of nitrogen have led W. Kirsten328 todevise a method depending on the conversion of carbon and carbon dioxideinto carbon monoxide and cornbustion of this with nickel oxide a t 1000".Conditions for application of the rapid combustion method to the deter-mination of nitrogen have been described.329The micro-Grote apparatus for the determination of halogens and sulphurhas been ~tandardised.~~~ A rapid combustion method 331 and an automaticcombustion method332 for these elements have been described.G. In-gram 333 has published data regarding the behaviour of manganese dioxidetowards nitrogen oxides with special reference to compounds containingchlorine and sulphur. W. Kirsten 334 recommends that in the determinationof halogens by dry combustion, the combustion products and the oxygenshould be allowed to react with hydrogen, forming water, which gives betterabsorption of the halogens as hydrides. The Zacherl-Krainick apparatus 335for the alkalimetric determination of halogen has been modified to deal with318 Mikrochirn. Acta, 1953, 41.3l9 R. L6vy and B. Cousin, Bull. SOC. chiwz., 1952, 19, 728.320 W. H. Jones, Analyt. Chew., 1953, 25, 1449.322 R. D. Hinkel and R. Raymond, Analyt. Chem., 1953, 25, 470.323 A. Konovalov, Ind.Chim. belg., 1953, 18, 339.324 F. J. Scandrett, Analyst, 1953, 78, 734.326 Analyst, 1953, 78, 500.328 Ibid., p. 121.330 B.S.I. Specif., 1953, No. 1428, Pt. A 4.331 P. Gouverneur and H. van Dijk, Annlyt. Chim. Acta, 1953, 9, 59.332 T. T. W'hite, C. J. Penther, P. C. Tait, and F. R. Brooks, Analyt. Chew., 1953, 25,334 Mikrochern. Mikrochim. Acta, 1952-1 953, 40, 170.335 31. K. Zacherl and H. G. Krainick, Mikrochem., 1932, 11, 61.321 Nature, 1953, 172, 1104.325 Analyt. Chem., 1953, 25, 968.327 Mikrochem. Mikvochim. Acta, 1952-1953, 40, 359.329 G. Ingram, Mikrochim. Acta, 1953, 131.1664. 333 Mikrochim. Acta, 1953, 71358 ANALYTICAL CHEMISTRY.compounds which also contain nitrogen and Modified methodsfor determination of chlorine and bromine by sodium fusion336 and bypotassium-silver dichromate digestion 337 have been described.Organiciodine can be converted by potassium chlorate-perchloric acid into iodate,which is then determined by standard methods.33s Compounds containingfluorine are decomposed in a specially designed bomb with sodium or potas-s i ~ m , ~ ~ ~ and the fluorine is titrated with thorium nitrate and a standardcomparison technique. Organic sulphur may be converted into benzidinesulphate and determined titrimetri~ally.~~~ In compounds containingnitrogen in addition to sulphur, combustion, precipitation of the stllphate by4-amino-4’-chlorodipheiiyl and subsequent alkalimetric titration, avoidsinterference from nitrogen and halogen.341Methods for determining silicon, bound in various ways, in organiccompounds, have been described.342 Phosphorus can be converted into thephosphovanadomolybdate.343 Antimony can be determined in compoundscontaining nitrogen and chlorine by wet digestion, solution in hydrogenbromide-bromine, reduction and precipitation as sulphide or titrimetricdetermination with standard b r ~ m a t e .~ ~ ~ Selenium compounds are decom-posed with sodium peroxide to selenate, which liberates 6 equivalents ofiodine for each selenium atom.344 Tellurium compounds are digested inperchloric acid, excess of standard dichromate is added, and the excess isdetermined with ferrous solution sodium diphenylaminesulphonate beingused as indicator.345The determination of weak acids by titration to the phenolphthaleinend-point has been examined 346 with special reference to the determinationof carboxyl, acetyl, benzoyl, or C-methyl groups.The titration must becarried out in cold solution, as the end-point in warm solution is unsatis-factory. Carbonyl compounds can be determined either by precipitation assemicarbazones and titration with iodate or by titration with hydroxylamine,a special bromophenol-blue indicator matching technique beingThey can also be determined 348 by addition of a measured excess of 2 : 4-dinitrophenylhydrazine, the excess being reduced by titanous chloride, andthe unchanged titanium(II1) being determined by titration with iron(II1).Twelve equivalents of titanous chloride are required for one molecule of thedinitro-compound.A method for the sernimicro-determination of thebenzoyl group has been des~ribed.3~~ Primary amines can be determinedgasometrically by liberation of nitrogen with nitrous acid.350 In suitable3350 D. S. Rao and G. D. Shah, Mikrochem. Mikrochim. Acta, 1962-1053, 40, 254.336 L. J. Lohr, T. E. Bonstein, and L. J. Frauenfelder, Analyt. Chem., 1953, 25, 1115.337 J. A. C. van Pinxteren, Phnrm. WeekbEad, 1953, 88, 489.338 B. Zak and A. J. Boyle, J . Amer. Pharm. Assoc., 1952, 41, 260.339 R. Belcher, E. F. Caldas, S. J . Clark, and A. Macdonald, Mikroclzim. Acta, 1953,341 R. Belcher, A. J. Nutten, and W. I. Stephen, Mikrochim. Acta, 1953, 51.342 R. Nagel and H. W. Post, J . Org. Chewz., 1952, 17, 1379.343 T. S. Ma and J. D. McKinley, Mikrochim.Acta, 1953, 4.343a N. T. Wilkinson, Analyst, 1953, 78, 165.344 G. Kainz and A. Resch, Mikrochem. Mikrochim. Acta, 1952-1953, 40, 332.345 F. H. Kruse, R. W. Sanftner, and J. F. Suttle. Analyt. Chem., 1953, 25, 500.346 H. Jerie, Mikrochena. Mikrochim. Acta, 1952-1953, 40, 189.347 A. J. Fevell and J . H. Skellon, Analyst, 1953, 78, 135.348 W. Schoniger, H. Lieb, and K. Gassner, Mikrochim. Acta, 1953, 434.34s E. von Schivizhoffen and H. Danz, 2. anal. Chem., 1953, 139, 81.350 G. Kainz, Mikrochiwz. Acta, 1953, 349.283. 340 M. Chambon and H. Guyot, Ann. Plzarm. franc., 1952, 20, 685WILSON : INSTRUMENTAL METHODS. 359solvents primary, secondary, and tertiary amines can be differentiated bypotentiometric or indicator tit ration^.^^^ The reaction between titanouschloride and nitrobenzene has been examined.352 Errors in the usualmethod for the determination of N-methyl groups have been d i s c u ~ s e d .~ ~A thermometric and a conductometric method for determination of diazo-compounds have been described.354tartaricq ~ i n o l i n e . ~ ~ ~permanganate 361 and with copper(II1) periodate 362 have been investigated.Methods have been proposed for the determination of formicformaldehyde,367 methanol,358 organic ~ u l p h i d e s , ~ ~ ~ andThe reactions taking place in oxidations of organic compounds with7. INSTRUMENTAL METHODS.Electroana1ysis.-Electrochemical deposition methods in metallurgicalanalysis have been reviewed.363 A portable electroanalyser 364 and mercury-cathode cells 3 ~ ~ 6 9 have been described. Copper has been determined byusing an isolated anode to prevent slowing down of the determination throughre-oxidation of cuprous ion at the anode.370 Apparatus for the automaticcontrol of cathode potential has been described,371 and controlled-potentialanalysis has been applied t o the determination of zinc in brass.372 Copper,lead, and tin have been analysed in mixtures by deposition of copper andthen lead on the cathode, the tin being complexed to prevent deposition.373Silver, copper, and cadmium have been determined in mixtures.374 Theferric-ferrous system has been used to control cathode potential in thedeposition of ~ilver.37~ Bismuth, copper, and lead have been determinedin mixtures.37c Although apparently not yet utilised in electrodepositionanalysis, the effects of ultrasonic waves on electrode processes have beendescribed, and it has been pointed out that both the character of the depositand the composition, in the case of mixtures, may be altered, thus suggestingthat the effects of these waves might have some use in this field.377351 J. S.Fritz, Analyt. Chem., 1953, 25, 407.352 S. A. Newton, F. J. Stubbs, and Sir C. Hinshelwood, J., 1953, 3384.353 F. Franzen, W. Disse, and K. Eysell, Mikrochinz. Actu, 1953, 44.354 R. A. Paris and J. Vial, Ann. Chim. analyt., 1952, 34, 223.355 J. W. Hopton, Analyt. Chim. Acta, 1953, 8, 429.356 G. G. Rao and H. Sankegowda, Curr. Sci., 1952, 21, 188.357 J. I. de Jong, Rec. Trav. chim., 1953, 72, 356.358 D.A. Skoog and M. Budde, Analyt. Chem., 1953, 25, 822.359 W. H. Houff and R. D. Schuetz, ibid., p. 1258.360 D. Koszegi and E. SaIg6, 2. anal. Chenz., 1952, 136, 411.“ul A. Y . Drummond and W. A. Waters, .J., 1953, 435.302 G. Beck, Mikrochenz. Alikvoclzim. Acta, 1952-1953, 40, 258.363 T. S. West, Metallurgia, 1952, 46, 313.364 P. S. Farrington and R. L. Pecsok, J . Chew. Edzu., 1953, 30, 461.365 G. H. Aylward and H. V. Wooldridge, Analyst, 1953, 78, 386.366 V. A. Zarinsky, J . Anal. Chem., U.S.S.R., 1952, 7, 185.367 R. Bock and K.-G. Hackstein, 2. anal. Chew., 1953, 138, 339.368 R. B. Hahn, Analyt. Chew., 1953, 25, 1740.369 H. Coriou, J. HurC, and N. Meunier, Analyt. Chim. Acta, 1953, 9, 171.370 D. G. Foster, Analyt. Chew., 1953, 25, 1557.371 J.F. Palmer and A. I. Vogel, Amzlyst, 1953, 78, 428.372 D. G. Foster, Analyt. Chem., 1953, 25, 669.373 G. H. Aylward and A. Bryson, Analyst, 1953, 78, 651.374 R. W. C. Broadbank and €3. C. Winram, Metallurgia, 1953, 47, 155.375 G. Nonvitz, ibid., 48, 47.377 S. Barnartt, Quart. Reviews, 1953, 7, 84.376 Idem, ibid., 47, 157360 ANALYTICAL CHEMISTRY.Coulometry and Related Topics.-Coulometric titrations have beenreviewed critically and comprehensi~ely.~~~ A simple gas coulometer 379and apparatus for automatic coulometric titration 380 381 have been de-scribed. Because of the increased use of coulometric titrations, the coulombhas been suggested as the primary standard in all titrimetric processes inpreference to any chemical standard.382 I t has been shown that it is possibleto deduce correctly from polarographic investigations the conditions requiredfor obtaining optimum yields of coulometric reagent~3~3 Coulometrictitrations and back-titrations where oxidants and reductants are alternatelygenerated have been successfully carried out .384 Uranium has been deter-mined coulometrically by bromine 385 and by cerium(1v) .386 Thiosulphatehas been determined by electrically generated i0dine.~87 The coulometricdetermination of cadmium and zinc with stationary mercury-plated platinumelectrodes or, less satisfactorily, with amalgamated silver electrodes may beutilised in very dilute solution.388 Coulometric control has been applied tothe determination through electrodeposition of elements which normallydeposit together and therefore cannot be separated by controlled-potentialmethods.389 Thus in the deposition of chlorine and bromine on a silverelectrode two equations are obtained, one from the total number of coulombsrequired, which depends on the total number of equivalents deposited, andone from the total weight in grams of the deposit.The method is onlypossible if there is a considerable difference in the equivalent weights of thetwo elements.Polarography .-Polarographic instruments, technique, and literaturehave been extensively reviewed.390 The general theory of polarographicwaves391 and of irreversible waves 392 has been treated by several authors. Therising portion of reversible waves,393 the anomalous wave occurring after anormal wave in solutions of high ionic strength,394 and the influence of slow re-actions on the shape of the wave 395 have been studied. Simple 396 and photo-graphic-recording research 397 and cathode-ray 398 polarographs and a water-jacketed polarographic cell 366 have been described. J.Heyrovsky 399 hasapplied a polarographic oscilloscope to rapid qualitative analysis of ores, to378 P. S. TutundiiC, Autalyt. Chim. Actn, 1953, 8, 168.379 I. Berkes, Mikrochem. Mikrochim. Acta, 1952-1953, 40, 160.380 W. N. Carson, Analyt. Chem., 1953, 25, 226.381 E. N. Wise, P. W. Gilles, and C. A. Reynolds, ibid., p. 1344.382 P. S. TutundEiC, Analyt. Chim. Acta, 1953, 8, 182.J. Badoz-Lambling, ibid., 1952, '4, 585.384 P. S. Farrington, D.J. Meier, and E. H. Swift, Analyt. Chern., 1953, 25, 591.385 W. N. Carson, ibid., p. 466.386 N. H. Furman, C. E. Bricker, and R. V. Dilts, ibid., p. 482.387 P. S. TutundiiC and S. MladenoviC, Analyt. Chim. Acta, 1953, 8, 184.388 K. W. Gardiner and L. B. Rogers, Analyt. Chem., 1953, 25, 1393.389 W. M. MacNevin, B. B. Baker, and R. D. McIver, ibid., p. 274.390 J. A. Lewis, Ind. Chem. Chem. Manuf., 1953, 29, 6, 58, 125, 172.391 P. Delahay, J . Amer. Chem. Soc., 1953, 75, 1430.392 P. Kivalo, K. B. Oldham, and H. A. Laitinen, ibid., 1953, '75, 4148; T. Berzinsand P. Delahay, ibid., p. 5716; P. Delahay, ibid., p. 1190.393 K. B. Oldham, P. Kivalo, and H. A. Laitinen, ibid., p. 5712.394 L. Meites, ibid., p. 3809.395 J. Badoz-Lambling and R.Gauguin, Analyt. Chim. Ada, 1953, 8, 471.396 €3. W. hlundy and N. W. Allen, J . Chem. Educ., 1953, 30, 143.397 F. J. Bryant and G. F. Reynolds, Analyst, 1953, '48, 373.398 G. F. Reynolds and H. M. Davis, ibid., p. 314.399 J. Heyrovsky, Analyt. Chim. Acta, 1953, 8, 283WILSON : INSTRUMENTAL METHODS. 361the detection of impurities in organic compounds, and to qualitative gasanalysis. Determinations have been carried out with rotating 400 and withstationary 401 mercury-plated platinum electrodes, a large stationary poolof mercury being used instead of a dropping-mercury cath0de.~02 Theanalysis of flowing samples, with use of automatic control, has been investig-ated.403* 404 The polarograph has been applied to the estimation of currentefficiency of coulometric proces~es,~~~y 405 and to the continuous determinationof ions discharged from a chromatographic column.406 Studies have beenmade of polarographic behaviour in concentratedcalcium chloride solutions 407and in acetate solutions.408 The application of polarography to the examin-ation of the nature of complexed cations has been discussed.4osPolarographic methods have been described for the determination ofnitrite,410 nitrate,411,412 mixtures of hydrogen peroxide with organic per-o x i d e ~ , ~ ~ ~ , 414 tellurium,415 germaniumI4l6 and alkali metals and alkaline-earth metals.4l7 Calcium has been determined indirectly by precipitationwith chloranilic acid.418 Methods have been proposed for zinc 419 andc0pper.41~9 420 Aluminium has been determined indirectly by measurementof the reduction of the polarographic wave by ethylenediaminetetra-acetica ~ i d .~ 2 l Methods have been described for indium,422 ir0n,~2~chromi~m,~23 molybdenum,425 lead,426 titanium,427 ~ i r c o n i u m , ~ ~ ~ ~ 429 andosmium.430 Polarography has been suggested as a means of determiningacid anhydrides.431Amperometric Titrations-The best conditions for amperometric deter-minations at const ant voltage can be established by polarographic investig-400 W. D. Cooke, Analyt. Chem., 1953, 25, 215.401 T. L. Marple and L. B. Rogers, ibid., p. 1351.402 C. A. Streuli and W. D. Cooke, ibid., p. 1691.403 L. D. Wilson and R. J. Smith, ibid., p. 218.405 R. N. Adams, C. N. Reilley, and N. H. Furman, ibid., p.1160.406 W. Kemula, Roczn. Chem., 1952, 26, 281.407 G. F. Reynolds, H. I. Shalgosky, and T. J. Webber, Analyt. Chim. Acta, 1953, 8,408 M. A. DeSesa, D. N. Hume, A. C. Glamm, and D. D. DeFord, Analyt. Chem., 1953,409 K. H. Gayer, A. Demmler, and M. J. Elkind, J . Chem. Educ., 1953, 30, 557.410 D. T. Chow and R. J. Robinson, Analyt. Chem., 1953. 25. 1493.411 M. C. Rand and H. Heukelekian, ibid., p. 878.412 W. A. Lawrance and R. M. Briggs, ibid., p. 965.*13 H. Bruschweiler, G. J. Minkoff, and K. C. Salooja, Nature, 1953, 172, 909.414 W. M. MacNevin and P. F. Urone, Analyt. Chem., 1953, 25, 1760.415 E. Norton, R. W. Stoenner, and A. I. Medalia, J . Amer. Chem. Soc., 1953, 75, 1827.416 D. A. Everest, J., 1953, 660; A. K. Das Gupta and C.K. N. Nair, Analyt. Chim.417 M. Shinagawa, J . Sci. Hiroshima Univ.. 1952, 16, 145.418 B. Breyer and J. McPhillips, Nature, 1953, 172, 257; Analyst, 1953, 78, 666.419 G. B. Jones, Analyt. Chim. Acta, 1952, 7, 578.420 D. M. Hubbard and E. C. Spettel, Analyt. Chem., 1953, 25, 1245.421 D. Lydersen, 2. anal. Chem., 1953, 139, 401.422 M. Maraghini, Ann. Chim. appl., 1951, 41, 776.423 M. Perkins and G. F. Reynolds, Analyst, 1953, 78, 480.424 E. C. Mills and S. E. Hermon, Metallurgia, 1952, 46, 259, 266.425 L. Meites, Analyt. Chem., 1953, 25, 1752.4 2 6 I. M. Kolthoff, J. Jordan, and A. Heyndrickx, ibid., p. 884.427 R. P. Graham. A. Hitchen, and J. A. Maxwell, Canadian J . Chem., 1952, 30, 661.428 E. L. Colichman and W. H. Ludewig, Analyt. Chem., 1953, 25, 1909.429 R.P. Graham, E. VanDalen, and A. M. C. Upton, Canadian J . Chem., 1952, 30.431 C, Ricciuti, C. 0. Willits, H. B. Knight, and D. Swern, ibid., p. 933.404 Idem, ibid., p. 334.558, 564; 9, 91.25, 983.Acta, 1953, 9, 287.1069. 430 I. M. Kolthoff and E. P. Parry, Analyt. Chem., 1953, 25, 188362 ANALYTICAL CHEMISTRY.ation, and a relation can be derived between amperometric and potentio-metric tit ration^.^^^ Amperometric titration methods have been applied inthe determination of ammonia,433 ~ u l p h a m a t e s , ~ ~ ~ i0dine,~3~-~37thorium,439 and organic sulph~r.~~OPotentiometric Titrations.-The polarisation curve of an oxidation-reduction system has been discussed in relation to the dead-stop end-pointmethod of t i t r a t i ~ n .~ ~ ~ An electrometer for use in small-scale potentiometrictit ration^,^^^ apparatus for the dead-stop method which gives audible warningof the end-point 443 or gives a readily variable warning of the approach ofthe e n d - p ~ i n t , ~ ~ ~ a cell for potentiometric titrations in an inert atmosphere,366a micro-glass electrode,445 jacketed vessels for glass electrodes,446 and silverreference electrodes 4 4 7 9 448 have been described. S. Samson 449 has describeda method for the determination of chloride which uses two silver electrcdesa t a small potential difference; the current flowing between these is measuredby a sensitive galvanometer, and at the end-point the change in the electrodeprocesses cause a sharp break in the curve.Potentiometric titration methods have been proposed for boron in nickelb ~ r i d e , ~ ~ ~ and for tellurium,451 zinc,452 iron,453 titanium in the presence of~ a n a d i u m , ~ 5 ~ microgram amounts of fattyConductance Methods.-The principles of high-frequency conducto-metric titrations have been discussed.458 Causes of the difference between theconductometric and the true end-point in the titration of sulphate havebeen examined.459 Conductometric titration has been proposed for thedetermination of the concentration of sulphuric acid 460 and for the estimationof potassium 461 and ofColorimetry and Absorptiometry-Modern applications of the spectro-photometer in the ultra-violet and the visible region to analytical problemshave been reviewed.463 A collection of methods for use with the Lovibondand aldehydes.456> 457432 R.Gauguin and G. Charlot, Analyt. Chim. Acta, 1953, 8, 65.433 I. M. Kolthoff, W. Stricks, and L. Morren, Analyst, 1953, 78, 405.434 S. T. Hirozawa and R. C. Brasted, Analyt. Chem., 1953, 25, 221.435 G. Knowles and G. F. Lowden, Analyst, 1953, 78, 159.4a8 H. P. Kramer, W. A. Moore, and D. G. Ballinger, Analyt. Chenz., 1952, 24, 1892.437 I. M. Kolthoff and J. Jordan, ibid., 1953, 25, 1833.438 V. M. Peshkova and 2. A. Gallay, J . Anal. Chem., U.S.S.R., 1952, 7, 152.439 L. Gordon and C. R. Stine, Analyi!. Chem., 1953, 25, 192.440 C. L. Rulfs and A. A. Mackela, ibid., p. 660.441 G. Duyckaerts, Analyt. Chim. Acta, 1953, 8, 57.442 D. M. W. Anderson and C. T. Greenwood, Chem. and Ind., 1953, 476.443 H.A. Glastonbury, Analyst, 1953, 78, 682.444 R. E. Collier and D. J. Fricker, ibid., p. 440.445 E. F. Hartree, Biochem. J., 1952, 52, 619.446 S. Lewin, Chem. and Ind., 1953, 1193.448 R. A. Glenn, Analyt. Chem., 1953, 25, 1916.450 H. Blumenthal and W. Fall, Analyt. Chem., 1953, 25, 1120.451 I. M. Issa and S. A. Awad, Analyst, 1953, 78, 487.452 A. Mayer, G. Bradshaw, and J. Deutschman, ibid., 367.453 M. B. Schigol and N. B. Burchinskaya, J . Anal. Chem., U.S.S.R., 1952, 7, 289.454 M. C. Steele and F. M. Hall, Analyt. Chim. Acta, 1953, 9, 384.455 B. W. Grunbaum, F. L. Schaffer, and P. L. Kirk, Analyt. Chem., 1953, 25, 480.4 5 6 S. Siggia and E. Segal, ibid., p. 830.457 Idem, ibid., p. 640.459 D. Lydersen and 0.Gjems, 2. anal. Chem., 1952-1953, 137, 189.460 C. H. Wood, I n d . Chem. Chem. Manuf.., 1953, 29, 152.461 V. V. Udovenko and G. B. Pasovskaya, J . Anal. Chem., U.S.S.R., 1952, 7, 161.462 Idem, ibid., p. 158.447 E. Bishop, Analyst, 1953, 78, 149.440 Nature, 1953, 172, 1042.458 C. N. Reilley and W. H. McCurdy, ibid., p. 86.463 E. J. Stearns, Anslyt. Chenz., 1953, 25, 1004WILSON : INSTRUMENTAL METHODS. 363Comparator has been published.464 Numerous unexplained departures fromabsorptiometric theory in photoelectric determinations have been studied,and the conditions for ensuring the best performance of an instrument havebeen defined.465 The importance of testing the linearity of response ofphotoelectric instruments has been stressed.466 H.A. Liebhafsky and H. G.Pfeiffer467 recommend that Beer’s law should be redefined in terns ofabsorbing centres, since it is then applicable to the many cases in which theparticles of a suspended lake obey the law.R. H. Hamilton 4G8 has recommended the insertion of a glass plate in thesolution to be measured, transmittance being read before and after, in orderto produce the effect of adding a layer of solution of uniform thickness, thusavoiding the necessity for using matched tubes for determinations. Differ-ential colorimetry has been stated to give results of an accuracy comparablewith classical methods in certain analyses, even when used with relativelysimple photometers or in other cases where Beer’s law may not be valid.46gThe added importance of temperature effects in differential colorimetry hasbeen stressed.470 A simple spectrophotometer using an interference filter,471and a universal high-sensitivity photometer 472 have been described.Photometric methods have been recommended for the standardisationof potassium permanganate solutions 473 and for the complete analysis oflight all0ys.47~Methods have been proposed for the determination of chlorine witho-tolidine,475 NN-dimethyl-fi-phenylenediamine,475 barbituric andsilver thiocyanate ; 477 for fluorine with aluminium-h~matoxylin,47g~ 479with the thorium lakes of sodium alizarin~ulphonate,~~~ chrome-azurolS 481 or N-(4-o-arsenophenylazo-l-naphthyl)ethylenediamine ; 482 for ammoniawith sodium phenoxide-hypochlorite 483 or pyridine with bis-(3-methyl-l-phenyl-5-pyrazolone) 4g4 which can also be used for cyanate; for hydroxyl-amine with 8-hydroxyquinoline ; 485 for nitrite with Paminobenzenesulphonicacid ; 4g6 for phosphorus as molybdenum-blue ; 487-491 for arsenic as molyb-464 “ Handbook of Colorimetric Chemical Analytical Methods for Industrial, Re-search and Clinical Laboratories,” Salisbury, 1953.4 6 5 L.S. Goldring, R. C. Hawes, G. H. Hare, A. 0. Beckman, and M. E. Stickney,Analyt. Chein., 1963, 25, 869. 4 6 6 C. G. Cannon and I. S. C. Butterworth, ibid., p. 168.467 J . Chem. Educ., 1953, 30, 450.469 A. Ringbom and K. bterholm, ibid., p. 1798. 470 R. Bastian, ibid., p. 259.471 H. W. Safford and D. F. Westneat, J . Chem. Educ., 1953, 30, 343472 G. Oster, Analyt.Chem., 1953, 25, 1165.473 J . E. Ransford, J . Chem. Educ., 1953, 30, 350.4 7 4 M. Jean, Analyt. Chiwz. Acta, 1952, 7, 523.4 7 5 G. Lipps and P. Gaertner, 2. anal. Chem., 1953, 139, 188.476 E. Asmus and H. Garschagen, ibid., 138, 404.4 7 7 A. Bezerra Coutinho and M. Dulce Almeida, Anal. Assoc. qudm., Brasil, 1951,10, 83.478 J. S. Beveridge, G. J. Hunter, and B. J. MacNulty, Analyt. Chim. Acta, 1953, 9.480 J. M. Icken and B. M. Blank, Analyt. Chem., 1953, 25, 1741.481 D. Revinson and J. H. Harley, ibid., p. 794.482 H. F. Liddell, Analyst, 1953, 78, 494.483 J. P. Riley, d n a l y t . Chim. Acta, 1953, 0, 575.484 J. M. Kruse and M. G. Mellon, Analyt. Chem., 1953, 25, 1188.4 q 5 W. Prodinger and 0. Svoboda, Mikrochim. Acta, 1953, 426.486 J.M. Pappenhagen and M. G. Mellon, Analyt. Chem., 1963, 25, 341.487 F. L. Schaffer, J. Fong, and P. L. Kirk, ibid., p. 343.488 R. A. Chalmers, Aaalyst, 1953, 78, 32.491 A. Gee and V. R. Deitz, Analyt. Chem., 1953, 25, 1320,468 Analyt. Chem., 1953, 25, 399.330. 479 G. J. Hunter, B. J. MacNulty, and E. -4. Terry, ibid., 8, 361.H. W. Harvey, ibid., p. 110. 490 H. K. Lutwak, ibid., p. 661364 ANALYTICAL CHEMISTRY.denum-blue 492 or as arsenovanadoniolybdic acid ; 493 for oxygen in tin byamalgamation of the tin and determination as molybdenum-blue ; 494 forsulphur as bismuth ~ u l p h i d e , ~ ~ ~ as zinc sulphide and conversion intomethylene-bl~e,~~~ by molybdenum-blue 497 or with p-phenylenediamine ; 498for selenium and tellurium by solution in concentrated sulphuric acid; 499for tellurium as a red hydrosol ; 500 for carbon in titanium by nitration; 501for cyanide and thiocyanate with barbituric acid; 502 for cyanide with bis-(3-methyl-l-phenyl-5-pyrazolone) and pyridine ; 503 for thiocyanate with acopper-pyridine reagent ; 503 for boron with curcumin 504 or quinalizarin ; 505for silicon by molybdenum-blue.506, 507 The silicomolybdate colorimetricdetermination has been examined for a wide range of silicon : sodium ratios.508Potassium has been estimated through the cobaltinitrite as cobalt8-hydroxyquinoline complex 509 or by dipicrylamine ; 510 czsium throughthe cobaltinitrite and the Griess reaction; 511 calcium as the murexide513 through oxalate by the decrease in the colour of the ferricsalicylate complex,514 through the molybdate by conversion into molybdenumthiocyanate 515 or by oxalohydroxamic acid ; 516 magnesium with Solochrome-black ; 5179 518 zinc by Rh~damine-B,~~~ by di-2-naphthylthiocarbazone 520or by #-dimethylaminoazophenylarsinic acid ; 474 cadmium by dithizone 521or +-nitrodiazoaminoazobenzene (cadion) ; 522 mercury by 2 : 6-dimet hyl-hept-5-en-2-01; 523 copper by diethyldithio~arbamate,~~~9 525 by diethyl-ammonium dieth~ldithiocarbamate,~2~ 1 : lo-phenanthr~line,~~~ 2 : 9-di-methyl-4 : 7-diphenyl-1 : lO-phenanthr~line,~*~ 2 : 2'-dip~ridyl,~~~ 2 : 2'-di-493 H.Onishi and E. B. Sandell, Mikrochim. Acta, 1953, 34.4 ~ 1 3 D. K. Gullstrom and M. G. Mellon, Analyt. Chem., 1953, 25, 1809.494 L. Silverman and W.Gossen, Analyt. Chim. Acta, 1953, 8, 436.d g 5 H. Koren and W. Gierlinger, Mikrochim. Acta, 1953, 220.496 W. Sonnenschein and K. Schafer. 2. anal. Chem., 1953, 139, 15.497 P. 0. Bethge, Svensk Kem. Tidskr.. 1952, 64, 177.498 S. Musha, Sci. Rep. Res. Inst. T6hoku Univ., 1953, 5, A , 232.499 S. E. Wiberley, L. G. Bassett, A. M. Burrill, and H. Lyng, Analyt. Chem., 1953,501 G. Norwitz and 0. W. Simmons, Analyt. Chim. Acta, 1953, 9, 555.502 E. Asmus and H. Garschagen, 2. anal. Chem., 1953, 138, 414.503 J. M. Kruse and M. G. Mellon, Analyt. Chem., 1953, 25, 446.504 L. Silverman and K. Trego, ibid., p. 1264.5 0 5 B. A. Ripley-Duggan, Analyst, 1953, 78, 183.506 0. A. Kenyon and H. A. Bewick, Analyt. Chem., 1953, 25, 145.507 C. L. Luke, ibid., p.148.509 S. Baar, Analyst, 1953, 78, 353.510 R. Faber and T. P. Dirkse, Artalyt. Chem., 1953, 25, 808.511 C. Duval and M. Doan, Mikrochim. Ada, 1953, 200.612 L.-E. Tammelin and S . Mogensen, Acta Chem. Scand., 1952, 6, 988.513 11. B. Williams and J. H. Moser, AnaZyt. Chem., 1953, 25, 1414.514 F. Burriel Marti, J. Ramirez Mufioz, and E. Perndndez Caldas, ibid., p. 583.515 G. E. Harrison and W. H. A. Raymond, Analyst, 1953, 78, 528.516 S. K. Dhar and A. K. Das Gupta, J . Sci. I n d . Res., India, 1952, 11, B, 520.517 W. Discherl and H. Breuer, Mikrochem. Mikrochim. Acta, 1952-1953, 40, 322.518 A. E. Harvey, J. M. Komarmy, and G. M. Wyatt, Artalyt. Chem., 1953, 25, 498.519 G. Martin, Bull. SOC. Chim. Ciol., 1952, 34, 1174.520 A.E. Martin,Analyt. Chem., 1953. 25, 1853.522 E. Fisher, B. T. Estes, and J. E. Rose, Analyst, 1953, 78, 729.523 A. G. Brook, A. Rodgman, and G. F. Wright, J . Org. Chem., 1952, 17, 988.524 J. K. Livingstone and N. D. Lawson, Analyt. Chem., 1953, 25, 1917.525 J. M. Chilton, ibid., p. 1274.527 D. H. Wilkins and G. F. Smith, Analyt. Chim. Acta, 1953, 9, 538.528 Idem, Analyt. Chem., 1953, 25, 510.529 J. P. Mehlig and P. L. Koehmstedt, ibid., p. 1920.25, 1586. 500 R. A. Johnson, ibid., p. 1013.508 D. T. Chow and R. J. Robinson, ibid., p. 646.52L B. E. Saltzman, ibid., p. 493.526 P. F. Wyatt, Analyst, 1953, 78, 656WILSON : INSTRUMENTAL METHODS. 365quinolyl,s*, 530,531 N’-phenylsemicarbazide 532 or triphenylmethylarsoniumthiocyanate ; 533 silver by fJ-dimethylaminobenzylidenerhodanine ; 534 alu-minium in thorium by 8-hydroxyquinoline, thorium being masked by 4-sulphobenzenearsonic acid 535 or by or-picolinic acid ; 536, 537 cerium by ultra-violet photometry of a ceric-carbonate complex; 538 thallium as the halidecomplex, preferably the cldoro-one ; 539 manganese by diethylammoniumdiethyldithiocarbamate ; 526 rhenium by extraction as tetraphenylarsoniumper-rhenate and conversion into rhenium thiocyanate ; 540 iron as c h l ~ r o - , ~ ~ sulphat0-,~42 or oxalato-complexes,543 by t h i ~ c y a n a t e , ~ ~ ~ , 54s by 8-hydroxy-quinoline,546 by nitroso-R salt ,547 by photometric titration with ceric solu-tion, 548 by 1 : lO-phenanthr~line,~~~ by various alkylamino-phenanthrolines, 549by 4 : 7-diphenyl-1 : lO-phenanthr~line,~~~ by 2 : 6-bis-2’-pyridylpyridineand its alkyl derivatives,551 by thioglycollic by 5 : 6-benzoquin-aldinic by a-picolinic a ~ i d , 5 ~ ~ , 5549 555 by proto~atechualdehyde,~~~by c~pferron,52~ or by 5-3’-carboxy-2’-hydroxy-l’-methylazobenzene-4-sulphonic acid ; 149 cobalt by nitroso-R salt ,557-559 by 2-nitroso-l-naphthol, 560by t riphen ylmet hylarsonium t hiocyanat e, 561 as diet hyldithiocarbamate, 525or by 2 : 6-bis-2’-pyridylpyridine ; 551 nickel as the dimethylglyoximecomplex, 562 by 8-hydro~yquinoline,~~~ by sodium diethyldithiocarbamate 525or by p-mercaptopropionic acid; 563 chromium as dichromate 564 or bydiphenylcarbazide ; 565 molybdenum as molybdenum thiocyanate in thevisible 5660rin theultra-violet region,567 by3 : 4-dimercaptotoluene (dithiol),56s530 R.J. Guest, Analyt. Chem., 1953, 25. 1484.531 J. Hoste, J. Eeckhout, and J. Gillis, Analyt. Chiin. Acta, 1953, 9, 263.532 E. M. Skibina, J . Anal. Chem., U.S.S.R., 1952, 7, 244.533 K. W. Ellis and N. A. Gibson, Analyt. Chim. Acta, 1953, 9, 368.534 A. Ringbom and E. Linko, ibid., p. 80.535 D. W. Margerum, W. Sprain, and C. V. Banks, Analyt. Chem., 1953, 25, 249.536 A. K. Majumdar and B. Sen, Analyt. Chim. Acta, 1953, 8, 378.537 Idem, ibid., p. 384.539 C. Merritt, H. M. Hershenson, and L. B. Rogers, ibid., p. 572.540 J. M. Beeston and J. R. Lewis, ibid., p. 651.541 G. A. Gamlen and D. 0. Jordan, J., 1953, 1435.542 R. Bastian, R. Weberling, and F. Palilla, Analyt. Chem., 1953, 25, 284.543 M.Bobtelsky, D. Chasson, and S. F. Klein, Analyt. Chim. Acta, 1953, 8, 460.544 S. 2. Lewin and R. S. Wagner, J . Chem. Educ., 1953, 30, 445.545 J. E. Houlihan and P. E. L. Farina, Analyst, 1953, 78, 559.546 E. Sudo, Sci. Rep. lies. I n s t . TGhoku Univ., 1952, 4, 347.547 J. A. Dean and J. H. Lady, Analyt. Chem., 1953, 25, 947.548 C. E. Bricker and P. B. Sweetser, ibid., p. 764.548 D. H. Wilkins, W. H. McCurdy, and G. F. Smith, Analyt. Chinz. Acta, 1953, 8, 46.550 R. E. Peterson, Analyt. Chem., 1953, 25, 1337.551 D. H. Wilkins and G. F. Smith, Analyt. Chzm. Acta, 1953, 9, 338.552 D. L. Leussing and I. M. Kolthoff, J . Amer. Chem. SOC., 1953, 75, 3904.553 A. K. hlajumdar and B. Sen, Analyt. Chim. Acta, 1953, 9, 529.554 Idem, ibid., p.536.556 M. Y. Shapiro, J . Anal. Chem., U.S.S.R., 1952, 7, 214.557 F. Burriel Marti and R. Gallego, Anal. real Sot-esp. Fis. Quim., 1952,4$, B, 793,801.558 R. Gallego, W. B. Deijs, and J. H. Feldmeijer, Rec. Trav. chim., 1952, 71, 987.55Q J. N. Pascual, W. H. Shipman, and W. Simon, Analyt. Chena., 1953, 25, 1830.560 H. Almond, ibid., p. 166.j 6 1 K. W. Ellis and N. A. Gibson, Analyt. Chim. Acta, 1953, 9, 275.562 W. A. Forster, Analyst, 1953, 78, 560.563 J. B. Lear and M. G. Mellon, Analyt. Chew., 1953, 25, 1411.564 A. A. R. Wood, Analyst, 1953, 78, 54.5 6 5 G. Norwitz and M. Codell, Analyt. Chim. Acta, 1953, 9, 646.566 J. L. Grigg, Analyst, 1953, 78, 470.667 G. E. Markle and D. F. Boltz, Analyt. Chem., 1953, 25, 1261.5B8 S. H . Allen and 31.H. Hamilton, Analyt. China. Acta, 1952, 7, 483.538 G. Telep and D. F. Boltz, Analyt. Chem., 1953, 25, 971.5 5 5 Idem, ibid., 8, 369366 ANALYTICAL CHEMISTRY.mercaptoacetic acid,569 disodium 1 : 2-dihydroxybenzene-3 : 5-disulphonate(tiron) ; 570 tungsten with quin01,~~l d i t h i 0 1 , ~ ~ ~ or as phosphovanadotungsticacid ; 493 uranium by 8--hydroxyq~inoline,~~~~ 573 dibenzoylmethane 574 orphotometric titration with ceric solution; 548 tin with hzematoxylin 575 oras the complex silicotungstic-hexamethylenetetraminetin(1v) salt ; 474 leadas the chloro-complex 539 or by dithizone using reversion technique; 576titanium by sulphosalicylic acid 577 or chromotropic acid; 578 zirconium by2-(2-hydroxy-3 : 6-disulpho-l-naphthy1azo)benzenearsonic acid (thorin) 579or quercetin.580 The determination of thorium by 8-hydroxyquinolineabsorptiometrically seems unsatisfactory since two distinct complexes areformed.581 Thorium can be determined by thorin ; 5829 antimony as iodo-antimonous acid 584 or by rhodamine-B; 585 vanadium by S-hydroxy-q ~ i n o l i n e , ~ ~ ~ , 586 c~pferron,~8~ 1 : 10-phenanthroline ; 588 niobium in solutionin hydrochloric acid in the ultra-violet region,589 by the thiocyanate com-plex 590 or q u i n 0 1 . ~ ~ ~ Niobium and tantalum can both be determined asperoxy-compounds by measurement in the ultra-violet region. 591 Tantalumcan be determined by pyrogallol 592 or pyrogallic acid; 571 bismuth by thio-urea,474 phosphotungstic a ~ i d , ~ 7 ~ or as the chloro-complex in the ultra-violetregion.539 Colorimetric and photometric methods for determining theplatinum metals have been reviewed.593, 594 Osmium can be extracted asthe tetroxide and determined by thi0urea.5~~ Ruthenium can be determinedby the same reagent.596 Metallic palladium in a finely divided conditioncan be determined by phosphomolybdic acid and carbon monoxide. 597Photometric methods have been used to determine polynuclear aromatichydrocarbons, 598 aliphatic sulphides as iodine complexes in the ultra-violet,5g9 oxalate as the ferric oxalate complex 543 or by the decrease inoptical density of the ferric salicylate complex,514 amino-groups with diazo-569 F.Will and J. H. Yoe, Analyt. Chem., 1953, 25, 1363.5 7 0 Idem, Analyt. Chim. Acta, 1953, 8, 546.5 7 1 L.Ikenberry, J. L. Martin, and W. J. Boyer, Analyt. Chern., 1953, 25, 1340.5 7 2 0. Silverman, L. Moudy, and D. W. Hawley, ibid., p. 1369.573 B. Hok, Svensk Kem. Tidskr., 1953, 65, 106.574 J. H. Yoe, F. Will, and R. A. Black, Analyt. Chem., 1953, 25, 1200.5 7 5 H. Teicher and L. Gordon, ibid., p. 1182.5 7 6 H. M. Irving and E. J . Butler, Analyst, 1953, 78, 571.5 7 7 M. Ziegler and 0. Glemser, Z. anal. Chem., 1953, 139, 92.578 W. W. Brandt and A. E. Preiser, Analyt. Chem., 1953, 25, 567.5 7 9 A. D. Horton, ibid., p. 1331.580 F. S. Grimaldi and C. E. White, ibid., p. 1886.581 T. Moeller and M. M. V. Ramaniah, J . Amer. Chew. Soc., 1953, 75, 3946.582 C. V. Banks and C. H. Byrd, Analyt. Chem., 1953, 25, 416.583 C. V. Banks, D.W. Klingman, and C. H. Byrd, ibid., p. 992.584 A. Elkind, K. H. Gayer, and D. F. Boltz, ibid., p. 1744.585 C. L. Luke, ibid., p. 674.587 H. H. Willard, E. L. Martin, and R. Feltham, ibid., p. 1863.5 8 8 G. Jantsch and F. Zemek, Z . anal. Chegn., 1953, 139, 249.589 J. H. Kanzelmeyer and H. Freund, Analyt. Chewz., 1953, 25, 1807.590 G. Norwitz, M. Codell, and F. D. Verderame, Analyt. Chim. Acta, 1953, 9, 561.591 F. C. Palilla, N. Adler, and C. F. Hiskey, AnaZyt. Chenz., 1953, 25, 926.598 J. I. Dinnin, ibid., p. 1803.594 F. E. Beamish and W. A. E. MacBryde, Analyt. Chim. Acta, 1953, 9, 349.595 R. D. Sauerbrunn and E. B. Sandell, ibid., p. 86.596 A. Musil and R. Pietsch, 2. anal. Chem., 1952-1953, 137, 259.597 R. A. McAllister, Analyst, 1953, 78, 65.598 R.Schnurmann, W. F. Maddams, and &I. C. Barlow, Analyt. Chenz., 1953, 25,5 8 6 N. A. Talvitie, ibid., p. 604.693 G. H. Ayres, ibid., p. 1622.1010. 599 S . H. Hastings, ibid., p. 420WILSON INSTRUMENTAL METHODS. 367tised sulphanilic acid or by precipitation with 1 -fluoro-2 : 4-dinitrobenzeneand conversion into 2 : 4-dinitrophenyl derivative of the amine,601 pyridineby cyanogen bromide and barbituric acid,602 and sugars by benzidine 603 or3 : 4-dinitrobenzoic acid.604Nephe1ometry.-Sulphur can be determined nephelometrically by oxid-ation with nitric acid-hydrochloric acid-selenium to sulphate and conversionof this into barium ~ulphate.~O~ Glycol-ethanol-water mixtures have beenreported satisfactory for production of stable barium sulphate suspensions.606Selenium has been determined by reduction with ascorbic acid.607 Nephelo-metric determinations of calcium as oxalate,608 zinc as diethyldithiocarb-amate,603 tin by cupferron 474 or hydroxynitrophenylarsinic acid 610 havebeen reported. Nephelometric titration has been used for the determin-ation of calcium,611 aluminium, iron, and chromium 612 with phthalate; ofnickel with dimethylglyoxime ; 613 and of lead with Organicsubstances such as camphor, furfuraldehyde and isobutanol have been Lsedas indicators in the turbidimetric titration of aqueous solutions of salts, anda method of choosing a suitable indicator has been described.615Fluorimetry .-Fluorimetric methods of determination have been pro-posed for fluoride by the decrease of intensity of the fluorescence of di-hydroxyazo-dyes ; 616 for beryllium,617 aluminium,61s indium 619 as 8-hydr-oxyquinoline complexes ; and for uranium by fusion with sodium fluoride.620Emission Spectrography.-A method has been described for the rapidsemi-quantitative determination of 68 elements in one operation, by use ofstandard plates and visual comparison.621 Twenty-one common cationscan be identified with the spectroscope and a spark source, and the lowerlimits of identification for these have been determined.622 Chemical enrich-ment methods prior to spectrographic analysis of trace elements have beende~cribed.~23, 624 The spectrographic method has been applied to the deter-mination of trace elements in lubricating oils 625 and in zirconium andhafnium.626 A mode of procedure is described for determining residual6oo D.Fraser and H. G. Higgins, Nature, 1953, 172, 459.601 F. C. McIntire, L. M. Clements, and RI. Sproull, Analyt. Chem., 1953, 25, 1757.602 E. Asmus and H. Garschagen, 2. anal. Chem., 1953, 139, 81.603 J. I<. N. Jones and J . B. Pridham, Nature, 1953, 172, 161.1 3 ~ 4 E. Bore1 and H. Deuel, Helv. Chim. Acta, 1953, 36, 801.605 A. Steinbergs, Analyst, 1953, 78, 47.606 G. Toennies and B. Bakay, Analyt. Chem., 1953, 25, 160.b07 31. N. Rudra and S. Rudra, Curr. Sci., 1952, 21, 229.608 J . G. Hunter and A. Hall, Analyst, 1953, 78, 106.609 J . E. 0. Mayne and G. H. Noordhof, ibid., p. 625.610 AT. Jean, Analyt. Chim. Acta, 1953, 8, 432.611 M.Bobtelsky and I. Bar-Gadda, ibid., 9, 168.612 I d e m , ibid., p. 525.614 M. Bobtelsky and B. Graus, ibid., p. 163.615 A. I. Spiridonova, J . Appl. Chem., U.S.S.R., 1952, 25, 159.616 W. A. Powell and J. H. Saylor, Analyt. Chem., 1953, 25, 960.617 T. V. Toribara and K. E. Sherman, ibid., p. 1594.618 E. Goon, J. E. Petley, W. H. McMullan, and S. E. Wiberlev, ibid., p. 608.619 R. Bock and I<.-G. Hackstein, 2. anal. Chem., 1953, 138, 337.620 G. R. Price, R. J . Ferretti, and S. Schwarz, Analyt. Chem., 1953, 25, 322.621 C. L. VC'aring and C. S. Annell, ibid., p. 1174.622 B. McDuffie, J , Chem. Educ., 1953, 30, 454.623 F. A. Pohl, 2. anal. Chem., 1953, 139, 241.624 G. E. Heggen and L. W. Strock, Analyt. Chem., 1953, 25, 859.623 R. F.Meeker and R. C. Pomatti, ibid., p. 151.626 N. E. Gordon and R. M. Jacobs, ibid., p. 1605.613 M. Bobtelsky and Y . Welwart, ibid., pp. 281, 375368 ANALYTICAL CHEMISTRY.impurities where the impurities in the synthetic matching standards are notthe same as those in the unknown.627 Methods for the determination ofcalcium in biological materials have been reviewed.628 A rotating-discelectrode has been used in the determination of impurities in titaniumZirconium 6309 631 and hafnium 630 have been determined spectro-graphically. Gold has been concentrated from solutions in ethylcellulosebefore determinati~n.~~~ Methods have been proposed for the determina-tion of thorium and lanthanons in phosphate rock,633 for lanthanonsafter separation from uranium,634 for copper, cobalt, and molybdenumin plant materials,635 and for niobium in the presence of titanium andtantal~m.63~The flame photometer has been used to determine lithium in magnesiumalloys,637 sodium in Portland cement,638 and sodium and potassium in plantextracts,639 and other biological specimens.64o> 641 Calcium has been deter-mined in biological 642 and the alkaline-earth metals have beendetermined in mixtures.643Absorption Spectra.-The shift of low- and high-intensity absorptionbands with change of solvent has been investigated for a number of benzenederivatives and an attempt has been made to relate the shift to the natureof the interaction between the substituents and the s0lvent.~44 Either infra-red or ultra-violet absorption spectra can be used to provide a simple andspecific means of determining naphthalene.645 Flavones 646 have beenidentified by the ultra-violet absorption spectra of their ions in sodiumethoxide solution, and polynuclear hydrocarbons 646 as the correspondingmethoxy-compounds.647 The shift in absorption maxima shown by certainanthocyanins in the presence of aluminium chloride has been used 648 todistinguish them from similar compounds which show no shift.Infra-red spectroscopy has been used to distinguish the different poly-morphic forms of both organic and inorganic materials.649 For samples ofthe order of a microgram it has been recommended that a special beam-condensing system constructed from silver chloride lenses be used, andsamples of 10 pg.and upwards are pressed into 5-mg. potassium bromide627 J. K. Hurwitz, Analyt. Chem., 1953, 25, 1028.628 H.-U. Riethmiiller, Mikvochim. Acta, 1953, 178.629 H. A. Heller and R. W. Lewis, Analyt. Chem., 1953, 25, 1038.630 V. A. Fassel, A. M. Howard, and D. Anderson, ibid., p. 760.631 D. M. Mortimore and L. A. Noble, ibid., p. 296.632 J. A. Lewis and P. A. Serin, Analyst, 1953, '98, 385.633 C. L. Waring and H. Mela, Analyt. Chem., 1953, 25, 432.63.1 B, Helger and R. Rynninger, Svensk Kem. Tidskv., 1952, 64, 224.635 J. Smit and J. A. Smit, Analyt. Chim. Acta, 1953, 8, 274.1336 G. Charlot and J. Saulnier, Ann. Chim. analyt., 1953, 35, 51.637 E. E. Strange, Analyt. Chem., 1953, 25, 650.638 J. J. Diamond and L. Bean, ibid., p. 1825.639 H.M. Bauserman and R. R. Cerney, ibid., p. 1821.640 M. G. Woldring, Analyt. Chim. Acta, 1953, 8, 150.641 G. R. Kingsley and R. R. Schaffert, Analyt. Chem., 1953, 25, 1738.642 P. S. Chen and T. Y . Toribara, ibid., p. 1642.643 0. N. Hinsvark, S. H. Wittwer, and H. M. Sell, ibid., p. 320.644 H. E. Ungnade, J . Amer. Ckem. SOC., 1953, 75, 432.645 N. J. Klein and G. W. Struthers, Analyt. Chem., 1953, 25, 1818.646 G. H. Mansfield, T. Swain, and C. G. Nordstrom, Nature, 1953, 172, 23.647 R. L. Cooper, Chem. and Ind., 1953, 516.648 T. A. Geissman, E. C. Jorgenson, and J. B. Harborne, ibid., p. 1389.649 D. N. Kendall, Analyt. Chem., 1953, 25, 382WILSON : INSTRUMENTAL METHODS. 369tablets through which the beam is passed.650 Complex organic materialshave been identified by infra-red examination of the products producedunder controlled conditions of pyrolysis,651 and the mineral constituents ofrocks have been examined as a finely ground powder film spread on a rocksalt window.652 Aldehydes and ketones have been analysed as the 2 : 4-di-nitrophenylhydrazones.6s Differential methods are strongly recommendedfor accurate infra-red analysis, the difference in absorption for a particularband in the unknown sample and in a reference being determined.654In the last few years microwave spectroscopy, that is, determination ofthe absorption by matter of radiation with wave-lengths of 2-100 mm.(frequencies of 3000--150,000 Mc./sec.) has been developed, and this instru-mental method has found some applications to analytical problems.I t iscertain that the number and range of these applications will increase as themethod becomes more widely appreciated. The problems which have beendealt with hitherto are of a rather specialised nature, and several reviews ofpresent and possible future applications, as well as of the theoretical back-ground and instrumental methods, have recently appeared. 655-657Miscellaneous Instrumental Methods.-Simple and polynuclear aromaticcompounds have been detected unequivocally by the lise of a fusion techniqueunder the microscope, whereby the compound is allowed to react with2 : 4 : 7-trinitrofl~orenone.~~~ If the technique is properly followed, fourseparate melting points are obtained in a single experiment, these represent-ing that of the unknown itself, that of the addition compound between theunknown and the reagent, and those of the two eutectics formed by thetwo separate substances with the addition compound.This is recommendedas a general means of identifying the individuals of a limited class of com-pound, the requirement being that it is possible to find a suitable fusionreagent that will react with all the individuals. The behaviour of substanceswhich supercool before crystallisation, and the effect of this on the pseudo-eutectic temperatures recorded have been investigated by A. K0fler.65~9 660The determination of optical and crystallographic data for selected com-pounds which has been carried on throughout the past few years continues,and compounds for which data have been published include D-fructosehemihydrate,661 dibenzyl sulphide,662 5--hydroxytetra~ole,~~~ dibenzyl~ h t h a l a t e , ~ ~ ~ s ~ c c i n i m i d e , ~ ~ ~ lycoctonine monohydrate,666 trans-diethyl-stilbcestr01~~~7 l-naphthoic acid,668 ~alicylarnide,~~~ (A)-pinic acid,670660 D.H. Anderson and N. B. Woodall, Analyt. Chem., 1953, 25, 1906.G 5 1 D. L. Harms, ibid., p. 1140.652 J . M. Hunt and D. S . Turner, ibid., p. 1169.653 J. H. Ross, ibid., p. 1288.655 R. H. Hughes, Ann. N.Y. Acad. Sci., 1952, 55, 872.6s6 J. Sheridan, Chem. and Ind., 1953, 648.657 R. H. Hughes, Bull. Brit. Sci. I n d . Res. Assoc., 1952, 7, 37.658 I>. E. Laskowski, D. G. Grabar, and W. C. McCrone, AnaZyt. Chein., 1953, 25, 1400.659 iVlikrochem. Mikrochim Ada, 1952-1953, 40, 311.661 F.T. Jones, F. E. Young, and D. R. Black, Analyt. Chern., 1953, 25, 649.662 J. Krc and J. French, ibid., p. 198.663 K. Hattori, J. P. Horwitz, and E. Lieber, ibid., p. 353.664 J . Krc and W. Rila, ibid., p. 514.668 R. J. Hinch and W. C. McCrone, ibid., p. 675.666 R. M. Douglas and W. B. Cook, ibid., p. 836.667 H. A. Rose, R. J. Hinch, and W. C. McCrone, ibid., p. 993.6 6 8 W. C. McCrone, ibid.. p. 1126.669 W. C. McCrone and R. J. Hinch, ibid., p. 1277.654 C. F. Hammer and H. R. Roe, ibid., p. 668.6Go Ibid., p. 405.670 J. Krc, ibid.. p. 2420370 ANALYTICAL CHEMISTRY.erythromycin hydriodide h~drate,~7l hafnium oxide, Hf0,,672 2 : 3 : 4 : 6-te t ranitr oaniline, 672 met hylenebis- (N-pyrrolidone-2-carboxylic acid) ,673 and2-phenyl-1 : 2 : 3 : 2H-triazol-4-ylmethanol and related compounds.674The use of X-ray methods for analytical purposes has been extensivelyreviewed in a symposium.e75 Phosphates have been analysed by X-raymethods using magnesium oxide as an internal standard.6768.PHYSICAL SEPA4RATION METHODS.As pointed out in a previous Report,677 the divisions between some of theclasses of physical separation methods are so sketchily indicated that it isnot always possible to assign the methods with any degree of certainty. Asa consequence, although an attempt has been made to place most of themethods in their appropriate group, there must necessarily be considerableoverlap, and there must also be some work which is best assumed to havea general application.The types of separation in laboratory fractional distillation, and thebehaviour of non-ideal mixtures have been discussed.678 A method offractional crystallisation on paper,679 which is essentially similar to the long-established sensitive test for hzmin used in forensic work,68o bxt which maybe of more general application, has been described.Chromatography of inorganic materials, and in particular, partitionmethods, have been dealt with in two 691 There has been acritical examination of the factors influencing RF values in chromatographyon The Reporter’s warning 677 that artefacts may arise throughfailure to distinguish the forces being used in any particular separation hasbeen emphasised by the results published by a number of authors duringthe past year.D. P. Burma683 has shown that, although the primaryprocess responsible for many separations is undoubtedly partition, yet adsorp-tion by the cellulose, although a secondary phenomenon, cannot be neglected ;and much work is required before the mechanism for even the simplestseparations can be regarded as being on a sound footing. Other indicationsof the complicated processes are the observations that certain electrolytesare adsorbed as a whole on ion-exchange resins,684 the nature of the anion671 H. A. Rose, Analyt. Chem., 1953, 25, 1571.672 S. Geller and E. Corenzwit, ibid., p. 1774.673 I;. T. Jones, K. J. Palmer, and D. R. Black, ibid., p. 1929.674 R. N. Castle, Mikrochim. Acta, 1953, 196.6 7 5 H.A. Liebhafsky, Analyt. Chem., 1953, 25, 689; L. S. Birks, E. J. Brooks, andH. Friedman, ibid., p. 692; R. G. Steinhardt and E. J. Serfass, ibid., p. 697; M. E.Straumanis, ibid., p. 700; H. P. Iilug, ibid., p. 704; E. P. Bertin, ibid., p. 708; L. L.Merritt, ibid., p. 718; K. L. Yudowitsch, ibid., p. 721 ; R. Castaing and A. Guinier, ibid.,p. 724; W. F. Bradley, ibid., p. 727; S. F. Kern, ibid., p. 731 ; C. R. Hudgens and A. M.Ross, ibid., p. 734; B. Post and I. Fankuchen, ibid., p. 736; W. N. Lipscomb, ibid.,p. 737; J . Leroux, D. H. Lennox, and K. Kay, ibid., p. 740; C. W. Gould and S. T.Gross, ibid., p. 749; F. W. Neumann and C. W. Gould, ibid., p. 751.676 A. J. Mabis and 0. T. Quimby, ibid., p. 1814.6 7 7 Ann. Reports, 1952, 49, 333 et seq.678 E.F. G. Herington, Chem. and Ind., 1953, 26.679 R. C. Vasisth and M. S. Muthana, Natzrre, 1953, 172, 862.680 W. Ream and G. R. Freak, Biochem. J., 1915, 9, 161.683 Analyt. Chem., 1953, 25, 549.684 L. I . Katzin and E. Gebert, J . Amer. Chein. SOC., 1953, 75, 801.“ Chromatographic Methods of Inorganic Analysis,” F. H. Pollard and J. F. W.McOmie, London, 1953. 682 G. Zimmermann, 2. anal. Chem., 1953, 138, 321WILSON : PHYSICAL SEPARATION METHODS. 37 1of the resin and of the material being important ; that irreversible " absorp-tion" on to paper may take place through ion-exchange, whether thestationary phase is organic or water ; 685 that ion-exchange with the solventmay take place; 686 that salt interference may give rise to anomalous valcesin the chromatography of sugars; 687 that aldose and ketose sugars may beinterconverted by alkaline impurities in paper unless precautions are takento avoid such reaction ; 688 that where multivalent ions are concerned multiplespots frequently appear; 689 and that, as shown by an investigation in therange -50" to ZOO", temperature effects have a significant bearing onchromatographic separations.6s0Absorption Chromatography.-Reflectance photometry has been used todetermine quantitatively materials separated by paper chromat~graphy.~~~Cellulose sheets much thicker than ordinary filter-paper have beenrecommended as having a much greater loading capacity.G93 A holderfor a coiled strip allows a smaller containing vessel to be andrectangular pieces of paper with points or tongues on the edges have beenrecommended.695Chromatographic separations of pho~phate,~g~ niobium and tantalum,697and organo-metallic complexes,698 on alumina have been described.Thecopper complexes of pyridine bases 699 have been separated by mems ofpaper impregnated with copper chloride. Paper has been impregnatedwith 8-hydroxyquinoline ioo and alumina iO1 for the separation of cations,and with sodium hydrogen sulphite for the separation of aldehydes andketones.702 Cobalt has been separated i03 on an alumina column carryingnitroso-R salt; trace elements in water on a cellulose acetate column im-pregnated with a carbon tetrachloride solution of dithizone ; i04 and unsatur-ated organic acids on an alumina column impregnated with morin, whosefluorescence then indicates the zones.io5 Chromatographic separations ofmono- and di-saccharides, io6 pyrethrins, 'O7 vitamins, io8 and the methylesters of higher fatty acids i09 have been reported.The chromatography of gases and vapours, particularly with reference6 8 5 J. B. Schute, Nature, 1953, 171, 839.686 E. A. S. Cave11 and N. B. Chapman, Chew. and Ind., 1953, 1126; J. W. Baker6 8 7 S. Baar and J. P. Bull, ibid., p. 414. R. B. Duff, Chenz. and Ind., 1953, 898.689 A. S. Currey, Nature, 1953, 171, 1026.690 L. T. Chang, Analyt. Chem., 1953, 25, 1235.691 R. A. Wells, Quart. Reviews, 1953, 7, 307.692 S. V. Vaeck, Natuire, 1953, 172, 213.693 L. S. Cuendet, R. Montgomery, and F. Smith, J .Awzer. Chem. SOC., 1953, 75,695 F. Reindel and W. Hoppe, Naturwiss., 1953, 40, 245.696 M. A. Rangarajan, C. N. Venkatachallam, and B. S. Srikantan, J . Indian Chewt.698 A. A. K. Al-Mahdi and C. L. Wilson, Mikrochem. Mikrochim. A c f a , 1952-1!:63,700 Q. Fernando and J . P. Phillips, Analyt. Chenz., 1953, 25, 819.701 W. Kemula, Roczgz. Chenz., 1952, 26, 696.702 A. G. Newcombe and S. G. Reid, Nature, 1053, 172, 455.703 E. Jensen, Analyt. Chinz. Acta, 1952, 7, 561; J. A. Dean, Analyt. Chein., 1951,705 G. di Modica and P. F. Rossi, Ann. Chinz. analyt., 1952, 34, 271.' 0 6 W. 11. Corbett. Chenz. and I n d . , 1953, 1285. 707 J. Ward, ibid., p. 586.i o 8 J. A. Brown, Analyt. Chenz., 1953, 25, 774.709 F. R. Cropper and A. Heywood, Nature, 1953, 172, 1101.and A.J. Neale, Natiwe, 1953, 172, 583.2764. 694 V. Schwarz, Chem. and I d . , 1953, 102.SOL., 1953, 30, 281.40, 138.697 N. Tikhomiroff, Conzpt. rend., 1953, 236, 1263.J . Baudet, Conzpt. rend., 1952, 234, 2454.23, 1096. 704 D. E. Garritt, ibid., 1953, 25, 1927372 ANALYTICAL CHEMISTRY.to separations by displacement adsorption on charcoal columns, has beenextended. loIon Exchange.-Analytical applications of ion-exchange processes havebeen described 711 and a review has been made of the properties of differentAmerican , German, and Russian ion-exchange materials. 712 An extensivebibliography of analytical applications has been compiled. 713 Conductancemeasurements have been used to follow separations on ion-exchangecolumns.714 An indication has been given of a new use of ion-exchangeresins for the solution and determination of " insolubles " which may dis-solve when shaken during a period of time with a resin suspension, liberatingan equivalent amount of acid or alkali.7l3Ion-exchange separation has been used to determine copper in oils,715aluminium in zirconium,716 to separate iron and aluminium,717 to separatescandium, lanthanum, and yttrium,71s and lanthanons in general.7193 720The behaviour of ferric phosphate 721 and of platinum-group metals on ion-exchange columns has been investigated.7229 723Nitrate has been determined 724 and phosphate has been removed 7z5by ion exchange. I t has been stated that organic cations show a much moremarked pH dependence in relation to certain resins than do inorganiccations.726 Organic acids, 727y 728 organic salts, 729 aldehyde-ketone mix-tures , 730 sugars and related materials, 731-735 amino-acids and relatedmaterials,736> 737 proteins,73s and alkaloids 739 have been separated by ionexchange.The measurement of volume of resin beads has been extended to coverthe measurement of pH.740 The effect of certain cation-exchange resins onsolutions of oxidising materials has been investigated.'4l7 l O D. H. James and C. S. G. Phillips, J., 1953, 1600.7 l 1 0. Samuelson, " Ion-Exchangers in Analytical Chemistry," New York, 1953,7 l 2 D. I. Ryabchikov, M. M. Senyavin, and K. V. Filippova, J . Anal. Chem., U.S.S.R.,714 A. M. Baticle, Compt. rend., 1953, 236, 2055.715 H.Buchwald and L. G. Wood, Analyt. Chem., 1953, 25, 664.716 H. Freund and F. J. Miner, ibid., p. 564.7 1 7 H. Teicher and L. Gordon, Analyt. Chim. Acta, 1953, 9, 507.718 P. Radhakrishna, ibid., 8, 140.71s F. Trombe and J. Loriers, Compt. rend., 1953, 236, 1567.720 Idern, ibid., p. 1670.722 W. M. MacNevin and W. B. Crummett, Analyt. Chem., 1953, 25. 1628.723 P. C. Stevenson, A. A. Franke, R. Borg, and W. Nervik, J . Amer. Chem. Soc.,724 G. B. Jones and R. E. Underdown, Analyt. Chem., 1953, 25, 806.7!a5 R. B. Hahn, C. Backer, and R. Backer, Analyt. Chim. Ada, 1953, 8, 223.726 D. K. Hale, D. I . Packham, and K. W. Pepper, J., 1953, 844.727 H. H. Schenker and W. Rieman, Analyt. Chem., 1953, 25, 1637.72* H. S. Owens, A. E. Goodban, and J.B. Stark, ibid., p. 1507.729 C. H. van Etten and M. B. Wiele, ibid., p. 1109.730 G. Gabrielson and 0. Samuelson, Svensk Kem. Tidskr., 1952, 64, 150.731 J. D. Phillips and A. Pollard, Nature, 1953,171,41. 732 A. C. Hulme, ibid., p. 610.733 J. X. Khym and L. P. Zill, Nuclear Sci. Abstr., 1952, 6, 20.734 H. Zinner, Chem. Ber., 1951, 84, 780.735 M. A. Chambers, L. P. 221, and G. R. Noggle, J . Amer. Pharm. Rssoc., 1952, 41, 461.736 E. Schram, J. P. Dustin, S. Moore, and E. J. Bigwood, Analyt. Chim. Ada, 1953,738 N. I<. Boardman and S. M. Partridge, Nature, 1953, 171, 208.73s W. G. H. Edwards, Chem. and Ind., 1953, 488.740 C. Calmon, Analyt. Chem., 1953, 25, 490.7 4 1 N. Hartler and 0. Samuelson, Analyt. Chinz. Acta, 1953, 8, 130.E. L.Streatfield, Chenz. and I n d . , 1953, 1214.1952, 7, 135. 713 G. H. Osborn, Analyst, 1953, 78, 221.721 J. E. Salmon, J., 1953, 2644.1953, 75, 4876.9, 149. 737 J. S. Wall, Analyt. Chem., 1953, 25, 950WILSON : PHYSICAL SEPARATION METHODS. 373Extraction.-In a symposium on solutions of electrolytes in organicsolvents 742 the factors influencing extraction have been discussed.The partition of metal bromides between aqueous hydrobromic acid anddiethyl ether has been investigated. 743 Antimony(v) in hydrochloric acidsolution can be extracted by ethyl acetate.744 An a-butyl phosphate-carbontetrachloride mixture has been recommended for the extraction of metalthi~cyanates.'~~ Beryllium can be extracted by chloroform or ethyl acetateas the b ~ t y r a t e .~ ~ ~ Thorium has been extracted from pitchblende residuesby tributyl phosphate and tetraethyleneglycol dibutyl ether.747 The fluoridecomplexes of tantalum and niobium can be extracted and separated by usingdiisopropyl ketone,748 and zirconium and niobium as the mixed butylphosphoric acids can be extracted by di-n-butyl ether.749 In the determin-ation of phosphate, molybdophosphoric acid is the most suitable form forextraction and the most useful solvent is 20% butanol in chloroform.75oTitanium as cupferrate can be extracted with chloroform in the determin-ation of aluminium in titanium The copper-dithizone system inwater-carbon tetrachloride has been It has been noted thatextractions of diethyldithiocarbamates at low pH should be carried outrapidly owing to instability of the reagent.753 Disubstituted dithiocarb-amates have been used for extraction separations in the analysis of copperalloys.754 Technetium has been isolated by extraction as t etraphenyl-arsonium pert echnat e with chloroform. 755Partition Chromatography.-The existing technique for two-dimensionalpaper chromatography has been simplified by running spots obtained fromone solvent system on to separate strips for the application of further solventsystems. 756 Various techniques using circular disc paper chromatographyhave been r e ~ o r n m e n d e d . ~ ~ ~ - ~ ~ ~ A method has been devised for the auto-matic measurement of light absorption or fluorescence in paper separ-a t i o n ~ . ~ ~ ~ The relation between zone size and amount has been investig-ated.761 It has been suggested that there are numerous solvent systems inwhich gradient-elution analysis, that is, analysis with a continuously changingsolvent system, would be an improvement,762 and several instances of suchsystems are cited. H.S. Burton has stated that a very satisfactory support742 N. N. Greenwood, Nature, 1953, 172, 149.743 R. Bock, H. Kusche, and E. Bock, 2. anal. Chem., 1953, 138, 167.744 C. E. White and H. J. Rose, Analyt. Chem., 1953, 25, 351.745 L. Melnick, H. Freiser, and H. F. Beeghly, ibid., p. 856.746 A. K. Sundaram and S. Banerjee, AnaZyt. Chim. Acta, 1953, 8, 526.747 D. F. Peppard, G. Asanovich, R. W. Atteberry, 0. Du Temple, M. V. Gergel,A. W. Gnaedinger, G.W. Mason, V. H. Meschke, E. S. Nachtman, and I. 0. Winsch,J . Amer. Chem. Soc., 1953, 75, 4576.748 P. C. Stevenson and H. G. Hicks, Analyt. Chem., 1953, 25, 1517.749 E. M. Scadden and N. E. Ballou, ibid., p. 1602.750 C. Wadelin and M. G. Mellon, ibid., p. 1668.751 J. A. Corbett, Analyst, 1953, '78, 20.762 R. W. Geiger and E. B. Sandell, Analyt. Chim. Acta, 1953, 8, 197.753 A. E. Martin, Analyt. Chem., 1953, 25, 1260.7 5 4 F. F. Miller, K. Gedda, and H. Malissa, Mikrochem. Mikrochim. Acta, 1952-1953,756 F. P. W. Winteringham, Nature, 1953, 172, 727.7 5 7 K. V. Giri, ibid., 171, 1159.759 A. Saifer and I. Oreskes, Analyt. Chem., 1953, 25, 1539.760 J, A. Brown and M. M. Marsh, ibid., p. 1865.761 R. S. Srikantaii and C. N. Venkatachallum, J . Indian Chem.SOC., 1953, 30, 167.'62 M. Lederer, Nature, 1953. 173, 727.40, 373. 755 S. Tribalat and J. Beydon, Analyt. Chim. Acta, 1953, 8, 22.7 5 * H. Proom and A. J, Woiwod, ibid., p. 42374 ANALY 1 lLAL C ~ H c l V l l 3 l R I.is obtained by acetylation of the cellulose in ~ a p e r , 7 ~ ~ and asbestos chromato-graphy has been applied to a number of separations of inorganic cationpairs. 7G4Identification of spots on paper may be made specific by using successiveclipping in reagents, which must be applied in the correct order t o achievethis Ions with the same half-wave potential can first beseparated by chromatography before examining them polarographically. 7 6 7 9 768Partition chromatography has been used for the separation of lithium,sodium, and potassium,769 beryllium from aluminium and iron,77o traceimpurities in tin-lead alloys,771 analytical groups 111, IV, and V,772 alumin-ium in water,773 molybdenum, copper, and iron,774 thallium in organicmaterials,775 the per-compounds of titanium, vanadium, and molybdenum,776vanadium and molybdenum, 7 7 7 y 778 lanthanons, 779 radioactive isotopes frominactive material,7*0 uranium, copper, and iron,781 radium-D, -E, and -F, 782and actinium degradation products including francium.7833 784 The effectof potassium cyanide on the R p values of inorganic cations has beenstudied. 785Partition chromatography has been used in the analysis of hydrogenperoxide-organic peroxide mixtures,413 organic acids, 786-791 alcohols, 793y 793phenols, 7949 795 keto-acids, 796, 797 sugars and related substances, 798-802766763 Chem.and Ind., 1953, 1229.765 I. Smith, Nature, 1953, 171, 43.7 6 6 J . B. Jepson and I. Smith, ibid., 172, 1100.7 6 7 W. Kemula, Roczn. Chem., 1952, 26, 694.7~ W. Kemula and A. Gbrski, ibid., p. 639.76n D. P. Burma, Analyt. Chinz. Acta, 1953, 9, 513.770 C. L. Rao and J. Shankar, ibid., 8, 491.771 J. R. Bishop and H. Liebmann, Analyst, 1953, 78, 117.772 J. G. Surak, N. Leffler, and K. Martinovich, J . Chem. Educ., 1953, 30, 20.773 K.-E. Quentin, 2. anal. Chem., 1953, 139, 92.774 F. H. Pollard, J. F. W. McOmie, H. M. Stevens, and J. G. Maddock, J . , 1953,7 7 5 H. Diller and 0. Rex, 2. anal. Chem., 1952-1953, 137, 241.7 7 6 M. Lederer, Annlyt. Chim. Acta, 1953, 8, 259.7 7 7 A. Lacourt, G.Sommereyns, J. Hoffmann, S. Frank-Frederic, and G. Wantier,7 7 8 A. Lacourt, G. Sommereyns, A. Stadler-Denis, and G. Wantier, Mikrochem.7 7 9 M. Lederer, Compt. rend., 1953, 236, 1557.780 Idem, Analyt. Chim. Acta, 1953, 8, 134.7a1 A. Weiss, S. Fallab, and H. Erlenmeyer, Helv. Chim. Acta, 1952, 35, 1588.782 E. E. Dickey, J . Chem. Educ., 1953, 30, 525.783 M. Perey and J. P. Adloff, Compt. rend., 1952, 236, 1664.784 Idem, ibid., p. 1163. 785 W. F. Pickering, Analyt. Chim. Acta, 1953, 8, 344.786 J. E. LofAer and E. R. Reichl, Mikrochim. Acta, 1953, 79.787 A. R. Jones, E. J . Dowling, and W. J. Skraba, Analyt. Chem., 1953, 25, 394.788 J. W. Airan, G. V. Joshi, J. Barnabas, and R. W. P. Master, ibid., 1953, 25, 659.789 S.S. Phatak, A. P. Mahadevan, and V. N. Patwardhan, Curr. Sci., 1952, 21, 162.790 R. E. B. Duncan and J. W. Porteous, Analyst, 1953, 78, 641.791 H. J. Nijkamp, Nature, 1953, 172, 1102.792 A. Siegel and K. Schlogl, Mikrochem. Mikrochim. Acta, 1952-1953, 40, 383.793 S. dal Nogare, Analyt. Chem., 1953, 25, 1874.794 K. Schlogl and A. Siegel, Mikrochem. Mikrochim. Acta, 1952-1953, 40, 202.7Q5 T. R. Sweeney and J. D. Bultman, Analyt. Chem., 1953, 25, 1358.7~ D. J. D. Hockenhull, G. D. Hunter, and M. W. Herbert, Chem. and Id., 1953,797 D. Turnock, Nature, 1953, 172, 355.798 D. Gross and N. Albon, Analyst, 1953, 78, 191.79n B. D. E. Gaillard, Nature, 1953, 171, 1160.S. Gardell, Acta Chem. Scand., 1953, 7, 201,801 R. H. Bayly and E. J. Bourne, Nature, 1953, 171, 385.808 D. J.D. Hockenhull. Nature, 1953, 171, 982.764 B. N. Sen, Australian J . Sci., 1953, 15, 133.1338.ibid., p. 444.Mikrochim. Acta, 1952-1953, 40, 268.127U’ILSON : MISCEL1,ANEOUS. 375amines, 803 amino-acids, 804-808 phosphate esters, 809 t hioureas, 810 and com-pounds related to adrenaline.811Ionophoresis and Electrophoresis.-The mechanism of electrophoresison paper has been d i s c ~ s s e d . ~ ~ ~ - ~ ~ ~ An apparatus which can be applied to2 ml. of solution instead of the 11 ml. required by the standard apparatushas been described.815 Separations have been made of calcium and phos-phate ions,s16 lanthanons,sl7 amino-acids,818 sugars,819-822 vitamins,s2Aand keto-acid dinitrophenylhydra~ones.~~~Separations using high frequencies of 500-5000 k ~ ./ s e c . ~ ~ 5 and highvoltages of 40-60 v/cm. for long periods 826 have been described.9. MISCELLANEOUS.Radiochemical Analysis. -Applications of radio-isot ope techniques inanalytical chemistry have been surveyed 827-829 and isotope dilution methodshave been reviewed.830 Methods have been described for the synthesis oflabelled organic compounds. 831 Apparatus and counting techniques havebeen d e s ~ r i b e d . ~ ~ ~ - ~ ~ ~ Cations have been determined by the use of radio-active hydrogen s~lphide,~~5 potassium has been determined as cobalti-nitrite by use of radioactive c0balt,8~~ and the determination of germaniumhas been investigated by tracer methods.837 Zinc in aluminium alloys hasbeen determined by use of 65Zn.838 Analytical processes for zinc have beenevaluated for the gravimetric determination of zinc, tracer methods beingA.Wankmiiller, Naturwiss., 1952, 39, 133.R. C. Salander, M. Piano, and A. R. Patton, .4nalyt. Chem., 1953, 25, 1252.G. Curzon and J. Giltrou, Nature, 1953, 172, 356.A. P. Prior and T. P. Whitehead, ibid., p. 358.G. Ray, N. C. Ganguli, and S. C. Ray, ibid., p. 809.A. L. Levy and D. Chung, Analyt. Chem., 1953, 25, 396.E. Fletcher and F. H. Malpress, Nature, 1953, 171, 838.*lo A. Kjaer and K. Rubinstein, Acta Chem. Scund., 1953, 7, 528.811 D. M. Shepherd and G. B. West, Natzcre, 1953, 171, 1160.M. A. Jermyn and R. Thomas, ibid., 172, 72s.A. Tiselius, Discuss. Faraday Soc., 1953, 13, 29.M. Macheboeuf, Chenz.Weekblad, 1953, 49, 237.815 L. G. Longworth, Analyt. Client., 1953, 25, 1074.T. R. Sato, W. E. Kisieleski, W. P. Norris, and H. H. Strain, ibid., p. 432.M. Lederer, Compt. regzd., 1953, 236, 200.D. P. Burma, Analyt. Chim. Acta, 1953, 9, 518.F. Micheel and F.-P. van der Kamp, Angew. Clzem., 1952, 64, 607.8 ~ 0 L. Jaenicke, Naturwiss., 1952, 39, 86.822 A. B. Foster and M. Stacey, J . Appl. Chem., 1953, 3, 19.823 E. S. Holdsworth, Nature, 1953, 171, 148,a24 W. J. P. Neish, Rec. Trav. chim., 1953, 72, 105.825 Y. Hashimoto and I. Mori, Nature, 1953, 172, 542.826 D. Gross, ibid., p. 908.s27 “ Proceedings of Isotope Techniques Conference,” Vol. 2, London, H.M.S.O.,820 H. Seligman, Nature, 1953, 171, 588.830 J. J. Pinajian, J. E. Christian, and W.E. Wright, J . Amer. Pharm. Assoc., 1953,831 S. L. Thomas and H. S. Turner, Quart. Reviews, 1953, 7, 407.832 R. E. Connally and M. B. Leboeuf, Annlyt. Chem., 1953, 25, 1095.833 H. W. Kirby, ibid., p. 1238.834 E. A. Evans and J. L. Huston, Nuclear Sci. Abstr., 1952, 6, 211.835 P. C. van Erkelens, Nature, 1953, 172, 358.a36 E. Sanchez Serrano and I. Lopez Santos, Bol. radioact., Madrid, 1951, 24, 49.s37 L. K. Bradacs, 1.-M. Ladenbauer, and F. Hecht, Mikrochim. Acta, 1953, 229.838 K. Theurer and T. R. Sweet, AnaZyt. Chem., 1053, 25, 119.821 A. B. Foster, J . , 1953, 982.1952. P. C. Aebersold and E. A. Wiggin, J . C h e w Educ., 1953, 30, 229.42, 301; J. E. Christian and J . J. Pinajian, ibid., p. 304376 ANALYTICAL CHEMISTRY.u ~ e d .~ 3 ~ Niobium and tantalum 8403 841 and titanium 841 have been deter-mined radiochemically.Radioactivation.-Deuterium has been determined by measurement ofthe neutron emission in conjunction with a suitable source of y - r a y ~ . ~ ~ Neutron irradiation has been applied to the determination of copper,843thallium,844 metallic impurities in high-purity iron,845 tantalum,846 andthe rare uranium isotope (235U) in naturally occurring uranium. 847W. W. Meinke and R. E. Anderson 848 have investigated fully the possi-bility of using low-level neutron sources for activation analysis, and havedescribed the use of this method in the determination of silver, indium, andrhodium.Gas Analysis.-Apparatus for the microanalysis of 20 cu. mm. of gas 849and a simple procedure for the analysis of a sample of the order of severalcu. mm.850 have been described. Winkler-type apparatus for the determin-ation of oxygen,S51, 852 simplified Hempel pipettes,853 apparatus for theanalysis of fuel gases by combustion with oxygen,s54 and a photoelectricinstrument for continuous detection of hydrogen sulphide 855 have beenused.A reliable method for preparing ammoniacal cuprous chloride solutionfor absorption of carbon monoxide has been reported.856 Oxygen in metallicoxides has been determined by treatment with bromine trifluoride, 857 andan electrochemical determination of oxygen is possible by using the depolar-isation of a carbon cathode.858 Apparatus and methods for the determin-ation of oxygen in metals have been d e s ~ r i b e d .~ ~ ~ - ~ ~ ~Direct gas-gas titrations, using pressure measurements to evaluate theend-point, may be used to take advantage of the reactivity of many gaseoushalogen derivatives3 Thus chlorine, fluorine, chlorine monofluoride, andchlorine trifluoride can be titrated with gaseous hydrocarbons , and chlorinetrifluoride-fluorine or methane-ethane mixtures are examples of morecomplex systems which can be analysed by this means.Non-aqueous Solvents.-In titrations using non-aqueous solvents it has839 J . E. Vance and R. E. Borup, Analyt. Chem., 1953, 25, 610.840 T. F. Boyd and M. Galan, ibid., p. 1568.841 J . Beydon and C. Fisher, Analyt. Chim. Acta, 1953, 8, 538.842 C. P. Haigh, Nature, 1953, 172, 359.843 J . Pouradier, A.M. Venet, and H. Chateau, Anm. Chirn. analyt., 1953, 35, 125.844 C. J. Delbecq, L. E. Glendenin, and P. H. Yuster, Analyt. Chern., 1953, 25, 350.845 P. Albert, M. Caron, and G. Chaudron, Compt. rend., 1953, 236, 1030.846 A. Kohn, ibid., p. 1419.847 A. P. Seyfang and A. A. Smales, Analyst, 1953, 78, 394.848 Analyt. Chem., 1953, 25, 778.8 p 0 D. G. Madley and R. F. Strickland-Constable, Analyst, 1953, 78, 122.850 H. G. Heal, Nature, 1953, 172, 30.851 L. P. Pepkowitz and E. L. Shirley, Analyt. Chem., 1953, 25, 1718.852 E. L. Harper, ibid., p. 187.854 W. J. Gooderham, ibid., p. 477.855 L. Aldred and J . Clough, Ind. Chem. Chem. Manuf., 1953, 29, 515.8b6 B. B. Bach, J. V. Dawson, and L. W. L. Smith. Cham. and Ind., 1953, 1279.857 H. R. Hoekstra and J . J . Katz, Analyt. Chem., 1953, 25, 1608.858 M. G. Jacobson, ibid., p. 586.850 J . N. Gregory, D. Mapper, and J . A. Woodward, Analyst, 1953, 78, 414.860 W. J . McMahon and L. S. Foster, J. Chem. Educ., 1953, 30, 609.861 M. W. Mallett, A. F. Gerds, and C. B. Griffith, Amalyt. Chem., 1953, 25, 116.862 C. €3. Griffith and M. W. Mallett, ibid., p. 1085.863 W. S. Horton and J. Brady, ibid., p. 1891.853 R. W. Green, Chenz. and I d . , 1953, 103WILSON MISCELLANEOUS. 377been found 864 that proper selection of the solvent, or addition of varyingamounts of a different non-aqueous solvent, may markedly increase the easewith which the end-point can be determined. Weak bases such as tertiaryamines show a sharper break in the potentiometric titration curve whentitrated in acetic anhydride solvent mixtures.865 Phenols can be titrated indimethylformamide by using azo-violet as indicator, or in ethylenediaminewith o-nitroaniline as indicator. 866 High-frequency titrations of organicbases have been carried out in glacial acetic acid-perchloric acid mixtures.867A4pparatus made of polychlorotrifluoroethylene has been recommended forstudies, in particular polarographic, in hydrogen fluoride solvent systems. 868Catalysed Reactions-Iodine has been determined by measuring itscatalytic action on the rate of the reaction between cerium(1v) andarsenic(II1) 869-87l or by its catalytic effect on the fading of the ferric thio-cyanate colour.872 Osmium has been determined in submicrogram amountsby its catalytic action on the cerium(Iv)-arsenic(III) reaction.873 In additionto iodide, ruthenium also acts as a catalyst, but its effect can be prevented.Miscellaneous Methods.-Determina tion of water by Karl Fischer’smethod has been reviewed. 874 Sulphur dioxide and bromine in chloroformhave been used in the same way as the Karl Fischer reagent to determinewater in inert organic solvents.s75 A sharp visual end-point is given, butthe titration is interfered with by alcohols.Deuterium determinations have been improved by reducing the interiorsurfaces of the apparatus used for the reduction of water by zinc, thusreducing the “ memory ” effects of the walls in the isotopic e~timation.~7~Sedimentation methods have been applied to the semi-quantitativedetermination of lead, mercury, tungsten, silver,877 and vanadium 878in microgram samples of material. A coefficient of variation of 5-13% hasbeen recorded in these determinations.Automatic thermometric titrations have been carried out by use of athermistor, a potentioneter, and a constant-flow burette, and acid-base andprecipitation reactions have been successfully carriedSeveral determinations have been described which depend on measuringthe time of induction in well-known “ time reactions.” Thus fluoride hasbeen determined by measuring the amount by which it accelerates thereaction between iodide and the hydrolysis products of cerium(1v) ,880 thio-sulphate has been determined by the time taken for the appearance of864 C. W. Pifer, E. G. Wollish, and M. Schmall, Analyt. Chem., 1953, 25, 310.8 6 5 J. S. Fritz and XI. 0. Fulda, ibid., p. 1837.J. S. Fritz and R. T. Keen, ibid., p. 179.867 W. F. Wagner and W. B. Kauffman, ibid., p. 538.8 6 8 J. W. Sargent, A. F. Clifford, and W. R. Lemmon, ibid., p. 1727.8e9 G. H. Ellis and G. D. Duncan, ibid., p. 1558.870 A. Schleicher, 2. anal. Chem., 1952-1953, 137, 401.8 7 1 B. Rogina and M. DubravEiC, Analyst, 1953, 78, 594.8 7 2 I. Iwasaki, S. Utsumi, and T. Ozawa, Bull. Chem. SOC. Japan, 1953, 26, 108.873 R. D. Sauerbrunn and E. B. Sandell, Mikrochim. Acta, 1953, 22.8 7 4 V. G. Jensen, Dansk Tidskr. Farm., 1952, 26, 145, 170.875 R. Belcher and T. S. West, J., 1953, 1772.876 C. A. Dubbs, Aqzalyt. Chem., 1953, 25, 828.8 7 7 H. M. El-Badry and C. L. Wilson, Mikrochem. Mikrochiin. A d a , 1952-1953, 40,879 H. W. Linde, L. B. Rogers, and D. N. Hume, Analyt. Chem., 1953, 25, 404.225. 8 7 8 Idem, ibid., p. 230.J. L. Lambert, ibid., p. 271378 ANALYTICAL CHEMISTRT.cloudiness on addition of a standard amount of acid, and iodate or sulphitehave each been determined by the induction period in a mixture with aknown amount of the other.881 Copper content can be determined bymeasuring the time taken to decolorise ferric thiosulphate in the presence ofthiocyanate.ss2So-called " electron-exchange " polymers have been described.883$ 884These may be used to cause oxidation or reduction on a column, and arereversible, although not quantitatively so. However, unlike normal reduc-tors, the columns do not contaminate the solution being treated with otherions. It is pointed out that these resins in effect produce reactions of atype forecast by M. Tswett 885 in his early investigations on chromatographicseparations. Both batch and counter-current applications of the resins havebeen suggested.884Racemic mixtures have been resolved by fractional precipitation froma non-active solvent,886 and the statistical basis of such a separation hasbeen discussed. Electrophoresis in a strong centrifugal or magnetic fieldshould also, it has been claimedJa87 be capable of resolving mixtures ofstereoisomers.Chemical methods for the characterisation of bacteria have been re-viewed 888 and improvements have been proposed to the existing analyticalchemical tests.C. L. WILSON.S81 E. N. Ponomareva, J . Anal. Cheni., U.S.S.K., 1952, 7, 163, 168.882 H. Got8 and S. Suzutu, Sci. Rep. Res. Inst. TGhoku Univ., 1952, 4, 35.883 M. Ezrin, I. H. Updegraff, and H. G. Cassidy, J . Amer. Chem. Soc., 1953, 75, 1610.884 Idem, ibid., p. 1615.8e5 M. Tswett, Ber. Deutsch. bot. Ges., 1906, 24, 316.8 8 6 R. C. Ferreira, Nature, 1953, 171, 39.887 F. C. Lendrum, ibid., 172, 499.888 S. T. Cowan, Chem. mzd Ind., 1953, 883

ISSN:0365-6217    

DOI:10.1039/AR9535000336

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

INDEX OF AUTHORS’ NAMES.Aaron, A., 92.Abadir, B. J., 154, 188.Abdel-Akher, M., 254, 288,290, 323.Abd-el Halim, F. M., 103.Abe, Y., 206.Abeck, W., 117.Abel, E., 89.Abeles, R. H., 256.Abraham, B., 95.Abraham, E. P., 238, 269.Abraham, S., 310.Abrahamsen, N. S. B., 315.hbrahamson, E. W., 47,Acher, R., 268, 273.Acock, G. P., 74.Acquista, N., 12.Adamik, E. R., 280.Adams, E. G., 357.Adams, M., 288, 294.Adams, R., 138, 164, 187,Adams, R. N., 361.Addison, C. C., 105, 106.Addor, R. W., 233.Adickes, F., 320.Adler, N., 366.Adler, S., 107.Adloff, J. P., 374.Aebersold, P. C., 376.Aebi, A., 207, 208.Afanas’eva, E. M., 289.Agarwal, R. P., 343, 347,Aggarwal, S. L., 60.Ahlbrecht, A. H., 187.Ahmad, R., 180, 181.Ahrens, R., 181.Ahrland, S., 91.Ai, H.C., 65.Airan, J. W., 343, 374.Airoldi, R., 353.Ajl, S., 318.Akabori, S., 278, 294.Alberman. K. B., 214.Albert, P., 376.Alberti, C. G., 278.Albertson, N. F., 242, 280.Albon, N., 284, 285, 374.Albrecht, J. F., jun., 30.Album, H. E., 325.hldebert, F., 205.Alder, B. J., 82.Alder, K., 228.144.250, 251.349.Aldred, L., 376.Aldridge, W. N., 272.Alexander, E. R., 197.Alexander, G. B., 102.Alexander, P., 70.Alfrey, G. F., 87.Alfrey, T., 60.Alimarin, I. P., 343.Aliminosa, L. M., 170, 225.Allen, A. D., 143.Allen, A. O., 67.Allen, C. F., 174, 183.Allen, E., 338.Allen, I., 142.Allen, N . W., 360.Allen, P. E. M., 41.Allen, P. W., 10.Allen, R. D., 97.Allen, S. H., 365.Allerton, R., 260.Allinger, N., 183.Allinger, N.L., 173.Alm, R. S., 25G, 283.Al-Mahdi, A. A. K., 371.Almond, H., 365.Almy, E. F., 171.Alpert, M., 12.Altieri, P. E., 345.Alyea, H. N., 59.Ambrozhy, M. N., 345.Amell, A. R., 39.Amelung, D., 224.Amendolla, C., 170, 229.Ames, B. N., 237.Amiel, Y., 278.Amin, A. M., 341, 353.Amis, E. S., 55.Ammerer, L., 190,Amphlett, C. B., 64, 69.Anantakrishnan, S. V., 55.Anchel, M., 177.Anderegg, J. A., 51.Andersen, F., 10.Andersen, H. C., 28, 89.Andersen, H. M., 233.Andersen, R. S., 11, 12.Andersen, W. E., 10.Anderson, A. G., 170.Anderson, A. G., jun., 193.Anderson, C. E., 310.Anderson, D. A., 368.Anderson, D. H., 369.Anderson, D. M. W., 3C0,Anderson, F. A., 113, 114.362.379Anderson, H.H., 103, 104.Anderson, H. J., 236.Anderson, H. R., 45.Anderson, H. R., jun., 28.Anderson, H. V.. 223.Anderson, J. R. A., 339,Anderson, J. S., 70, 112.Anderson, R. B., 116.Anderson, R. C., 245.Anderson, R. E., 376.Anderson, R. J., 183.Ando, Y., 332.Andoh, B. Y. A., 253.hndrade, E. N. da C., SO.Andress, K. R., 106.Andrews, L. T., 49, 126,Andrianov, K. A., 31.Anet, E. F. L. J., 177.Angyal, S. J., 150, 174.Anker, H. S., 309.Ankli, P., 234.Anliker, R., 169, 212.Annau, E., 312.Annell, C. S., 367.Anner, G., 221.Anno, K., 254, 264, 265,Anous, M. M. T., 73.Ansell, E. G., 266.Anta, C., 69.Antonucci, R., 226.Aoki, K., 329.Appel, H., 31!1.Appel, R., 109.Araki, C., 327.Arcand, G. M., 100.Archer, J.G., 259.Archer, S., 113.Archer, W. L., 174.Archibald, R. M., 335.Ardell, B., 120.Ardizio, P., 206.Ariel, M., 354.Armand, M., 347.Armstrong, A. W., 339.Armstrong, W. D., 317.Arndt, F., 242.Arndt, U. W., 271.Aronoff, S., 284.Arpesella, L., 162.-4rreguin, B., 231.Arth, G. E., 168, 172, 219.Asanovich, G., 373.345.140, 188.266380 INDEX OF AUTHORS’ NAMES.Aschner, T. C., 150.Ash, L., 272.Ashbolt, R. F., 272.Ashley, J. N., 145.Ashmore, P. G., 43.Ashurst, I<. G., 52.Asmus, E., 363, 364.Asmus, F., 367.ASperger, S., 119.Asplund, R. O., 273.Asselineau, J., 183.Astill, B. D., 194.Astle, M. J., 171.Atack, D., 87.Atchley, W. A., 319.Aten, A. H. W., 49.Atherton, F. R., 250.Atkinson, B., 37.Atkinson, R.O., 280.Atoji, M., 99.Atteberry, R. W., 373.Attenburrow, J., 168.Atwater, N. W., 208.Aubert, J. P., 290.Aubrey, N. E., 198.Audubert, R., 79.Auerbach, V. H., 301, 312.Augestad, J. A., 256.Augier, J., 326.Ausloos, P., 23.Austin, A. T., 127.Avineri-Shapiro, S., 287.Avrami, M., 72.Awad, S. A., 362.Awad, W. I., 198.Axford, W. E., 13.Axtmayer, J. H., 330.Axworthy, A. E., 35.Ayer, D. E., 270.Aylett, B. J., 102.Aylward, G. H., 359.Aynsley, E. E., 111, 115.Ayres, G. H., 350, 366.Ayrey, G., 145.Rziz, D., 158.Azuara, J., 203.Baar, S., 364, 371.Babaeva, A. V., 121.Babcock, H. W., 22.Babcock, J. C., 226.Babko, A. K., 344.Bach, B. B., 376.Bach, S. J., 320.Backer, C., 372.Backer, H. J., 236.Bacon, J.S. D., 282, 283,Bacon, R. G. R., 53, 145.Bacq, 2. M., 302.Baddar, F. G., 198.Baddeley, G., 130, 150, 188.Baddiley, J., 244, 245, 302.Bader, A. R., 174.Bader, F. E., 248.Badger, G. M., 145, 155,198, 19!)., 200.284, 286.Badger, R. G., 49.Ba.doz-Lambling, J., 360.Bahr, G., 91.Baer, E., 184.Baer, TI. H., 264.Baer, J., 320.Baer, S., 53, 352.Bassler, K. H., 318.Bailar, J. C., 94, 119, 121Bailey, A. S., 183.Bailey, E. A., 47.Bailey, J. H., 10.Bailey, J. M., 292, 298, 300Bailey, K., 280, 304.Bailey, P. S., 137.Bailey, W. J., 190, 202.Bainova, M. S., 247.Bak, B., 10, 12, 113, 114.Bakay, B., 367.Baker, B. B., 360.Baker, B. R., 251, 265.Baker, C. G., 157.Baker, E. B., 99.Baker, J. W., 125, 134, 371.Baker, L.C. W., 100.Baker, N., 310.Baker, P. J., jun., 264.Baker, P. R. W., 357.Baker, R., 152.Baker, R. H., 204.Baker, W., 192, 195, 243.Balandin, A. A., 76.Baldridge, H. D., 246.Balfe, M. P., 143, 153.Ball, E. G., 312.Ballinger, D. G., 362.Ballou, N. E., 373.Balls, A. K., 271, 291, 294.Ballun, A. T., 266.Balmain, J. H., 309.Baltazzi, E., 169.Balwit, J. S., 66.Bamberger, R., 205.Bamford, C. H., 60, 61, 62.Banerjee, S., 373.BBnhidi, 2. G., 333.Banks, C. V., 55, 337, 365,Bannister, B., 220.Banus, J., 187.Baptist, V. H., 274.Baranger. P., 356.Barannikov, G. I., 349.Barb, W. G., 61, 188.Barban, S., 318.Barclay, J. L., 263.Bardinskaya, M. S., 286.Barefoot, R. R., 348.Bar-Gadda, I., 91, 104, 367.Barker, C.C., 278.Barker, G. R., 260.Barker, H. A., 302, 303, 318.Barker, J. A., 83, 85, 86, 88.Barker, S. A., 254, 266, 267,282, 283, 287, 288, 298,300.340.366.Barkley, L. B., 187, 219.Barlin, G. B., 174.Barlow, M. C., 366.Barnabas, J., 374.Barnafi, L., 269.Barnard, D., 145.Barnartt, S., 359.Barnden, R. L., 238.Barnes, C. S., 211.Barnes, R. A., 240.Barnstorff, H. D., 356.Barnum, C. P., 317.Barr, J. T., 336.Barrer, R. M., 102.Barrett, C. S., 71.Barrow, F., 280.Barrow, G. M., 16, 17.Barrow, R. I?., 21, 22, 27,Barry, C., 290.Barry, C. P., 262.Barry, V. C., 263, 264, 326,327. 328, 329.Barsh, M. K., 50.Bartenstein, C., 117.Bartholomew, R. J., 270.Bartlett, P. D., 60, 135, 143,Barton, D. H. R., 132, 202,Barton-Wright, E.C., 286.Basolo, F., 54, 89, 107, 120.Basolo, G., 54.Bastian, R., 363, 365.Bastiansen, O., 10.Bateman, L., 57.Bateman, L. C., 141.Bates, C. J., 64.Bates, G. R., 14.Bates, H. G. C., 52, 145.Bates, J. C., 313.Baticle, A. M., 372.Batik, A. L., 342.Batten, J. J., 57.Battersby, A. R., 248, 271.Batty, J. W., 178.Batzold, J . S., 65.Baudet, J., 371.Baudler, M., 106.Bauer, E., 36.Bauer, S. H.. 37, 94.Baughan, E. C., 33, 194.Baum, H., 298.Baumann, C. A., 232.Baumfeld, L., 344, 345.Bauserman, H. M., 368.Bawn, C. E. H., 52.Baxendale, J. H., 52.Baxmann, F., 155.Bayer, E., 107.Bayer, L., 216.Bayly, R. H., 374.Bayly, R. J.. 255, 256.Bayne, S.. 263.Baysal, B., 58, 59.Bazemore, A.W., 270.Bazen, J,, 341.29.144, 217.207, 208, 211, 214IBealing, F. J., 283, 284.Beam, W., 370.Beamish, F. E., 339, 348,350, 366.Bean, L., 368.Beaton, J. hL, 214.Beatty, C. H., 314.Beaven, G. H., 155.Beaver, J. J., 45.Beaver, W. D., 120.Bebbington, A., 300.Becher, H. J., 97.Beck, G., 359.Beclter, E. D., 44.Becker, R., 71.Beckett, C. W., 202.Beckett, R., 77.Beckman, A. O., 363.Beckmann, S., 205.Reckwith, .4. L., 129.Beecher, L., 14.Beeghly, H. F., 339, 373.Beerebooin, J . J., 218.Beeston, J . M., 365.Begoon, A., 133.Behr, H., 102.Beinert, H., 303, 304, 305,307, 308, 315.Bekebrede, W., 104.Belcher, R., 342, 347, 351,352, 358, 377.Belew, J. S., 175.Eelford, R. L., 56.Bell, D. J., 283, 285, 288,289, 290, 296.Bell, E.E., 11, 15.Bell, F., 154, 155, 158, 163,Bell, R. P., 55, 142.Bell, W. E., 42, 44.Bellamy, L. J., 14.Belleau, B., 243.Bellemans, A., 85, 88.Belman, S., 273.Belz, L. H., 89.Eenati, O., 237.Bendas, H., 278.Bender, M. L., 143.Bendich, A., 240.Benedetti-Pichler, A. A.,Benedict, W. S., 10, 12.Benesi, H. A,, 126.BeneSovB, V., 207.Benfey, 0. T., 134.Bengough, W. I., 60.Ben-Ishai, D., 280.Benjamin, B. M., 138.Benkeser, R. A., 123.Benner, K., 294.Bennett, F. W., 114.Bennett, J . M., 9.Bennett, W., 137.Bensey, I;. N., 11.Benson, S. W., 35. 42.Bentley, H. R., 211, 261.Bentley, R., 334.195.346.DEX OF AUTHORS’ NAMES. 381Benton, J. L., 147.Berg, E. W., 350.Bergel, F., 250.Berger, A., 280.Berger, G., 319.Bergmann, E. D., 163, 187,Bergmann, J. G., 54.Bergmann, W., 332.Berkes, I., 360.Berlie, M. R., 41.Berliner, E., 129, 144.Berliner, F., 129.Berner, E., 256.Bernfeld, P., 288, 289, 294,Bernhard, K., 321, 322.Bernhard, S. A., 171.Bernheim, F., 148.Bernheim, M. L. C., 148.Bernstein, H. J., 23.Bernstein, R. B., 12.Bernstein, S., 169, 226, 232.Bernt, E., 284.Berry, J . F., 185.Berry, J. W., 192.Bersin, T., 255.Berson, J. A., 198, 235.Berstein, I. A,, 66.Berthold, H. J., 110.Berthoux, J., 347.Bertin, E. P., 370.Berzins, T., 360.Bethell, D. E., 13.Bethge, P. 0.. 352, 364.Beton, J. L., 215.Betts, R. H., 51.Betzel, C., 146.Bevan, C. W. L., 129, 130.Bevanue, A., 254.Beveridge, J.S., 363.Bkvillard, P., 347.Bevington, J. C., 150.Bewick, H. A., 364.Beydon, J., 373, 376.Beyer, D. L., 198.Beyermann, H. C., 165.Beyler, R. E., 170, 219.Bey-les, R. G., 349.Bezerra Coutinho, A., 363.Bhagavantam, S., 18.Bharucha, K. R., 168, 170,Bhatlti, K. S., 349.Bhattacharyya, A. K., 258.Bhattacharyya, B. K., 232.Bhattacharyya, N. K., 207.Bhuchar, V. M., 355.Bichowsky, F. R., 24.Bickel, A. F., 148.Bickel, H., 244.Bickford, W. G., 182.Bielanski, A., 73.Bieliu H. J., 107.Bigegisisen, J., 40, 56, 57.Bigelow, L. A., 113.Eigwood, E. J., 372.189, 278.299.178.Biletch, H., 39.Binkley, W. W., 259.Birch, A. J., 216, 219, 227.Birch, S. F., 164, 202.Birchenough, M. J., 211.Bircumshaw, L. L., 76, 77,Bird, R., 291, 292, 294.Birkofer, L., 263.Birks, L.S., 370.Birmingham, J. M., 118.Birnbaum, S. M., 157.Birtwell, S., 240.Bischof, B., 214.Bischoff, F., 75.Bishop, E., 362.Bishop, J . R., 374.Bishop, R. R., 129.Bjellerup, L., 30.Blacet, F. E., 42, 44.Black, D. R., 369, 370.Black, H. K., 176, 339.Black, R. A.. 366.Black, S., 303, 304.Black, W. A. P., 322, 323,324, 325, 332, 334.Black, W. T., 187.Blackall, E. L., 127.Blackburn, S., 279.Blades, A. T., 39.Bladon, P., 224, 225.BlAha, K., 173.Blake, N. W., 126.Blanchard, P. H., 284, 285.Blank B. M., 363.Blank, I., 187.Blanke, M., 112.Blaser, B., 106.Elass, TJ., 206.Blatt, A. H., 195.Blauer, G., 60.Blicke, F. F., 203.Blinks, L. R., 331, 335.Blinn, F., 158.Blixenkrone-Mdler, N., 312.Bloch, K., 230, 231, 232,Block, B.P.. 90.Blom, J., 267, 289.Blommers, E. A., 144.Blomquist, A. T., 203.Blomstrom, D. C., 164.Bloom, B. M., 220.Blum, L., 317, 320.Blumenthal, H., 362.Blunden, H., 320.Blust, G., 170.Boag, J. W., 65.Boardinan, H., 51, 52, 144.Boardman, N. K., 279, 372.Boaz, H. E., 238, 249.Bobbitt, B. G., 312.Bobtelsky, M., 91, 104, 365,Bock, R., 359, 367, 373.Bock, R. M., 304, 305.Bode, H., 338.78, 115.308, 309, 318. 321.367382 INDEX OF AUTHOKS’ NAMES.Bodor, A,, 355.Bodur, H., 321.Bohm, A., 90.Bohm, H., 319.Bohme, H., 356.Boer, J . de, 80, 81, 85.Boettcher, A., 259.Bogert, V. V., 238.Boggs, E. M., 82.BognBr, R., 262.Bogorad, L., 234.Bohlmann, F., 168, 177.Rohn, C.R., 15.Boissonnas, R. A., 280.Bolhofer, W. A., 277.Bolland, J. L., 46, 148.Bolle-Taccheo, S . , 350.Bolliger, H. R., 259.Holling, J . M., 92.Boltz, D. F., 365, 366.Bond, A. C., 97.Rondhus, F. J., 129.Bondin, S. M., 116.Bondy, H. F., 195.Bonner, A., 56.Bonner, J., 231.Bonner, T. G., 126.Bonner, T. W., 69.Bonner, W. A., 138, 255.Bonsall, E. P., 59.Bonstein, T. E., 358.Boord, C. E., 201.Boozer, C. E., 57, 138.Borchers, C. E., 51.Bordwell, F. G., 131, 233.Borek, E., 308.Borel, E., 254, 367.Borelius, G., 71.Borg, R., 372.Born, H., 167.Born, M.. 81.Borup, R. E., 376.Bose, A. K., 164, 166, 242,Boston, C. R., 54, 120.Bothner-By, A. A., 57.Bott, R. W., 53, 145.Bottle, R. T., 289.Bounds, D.G., 173, 182.Bourdon, D., 353.l3ourgin, D. G., 16.Bourne, E. J., 150, 253, 254,255, 256, 266, 267, 282,287, 288, 292, 298, 300,258.323, 374.Bovey, L. F. H., 9.Bowden, I?. P., 79.Bowen, E. J., 45, 46.Bower, J. G., 115.Bowers, A., 212, 215.Bowes, J. H., 272.Bowie, E. J., 313.Bowyer, F., 126.Boxer, G. E., 270, 308.Boyd, D. K. J., 9, 12.Boyd, T. F., 376.Boyer, M. H., 51.Boyer, W. J., 366.Boyland, E., 145.Boyle, A. J., 358.BoziC, 13. I., 112.Brackman, D. S., 62.Bradacs, L. K., 375.Braddock, L. I., 356.Brader, W. H., jun., 131.Bradfield, A. E., 131, 207.Bradley, D. C., 103.Bradley, R. S., 73.Bradley, W., 156, 195.Bradley, W. F., 370.Bradshaw, G., 362.Bradt, P., 61.Brady, J., 376.Brady, J .C., 126.Brady, 0. L., 143.Brady, R. O., 308, 309, 310,Brandt, G. R. A., 114.Brandt, W. W., 366.Brandy, J. H., 45.Brannock, K. C., 12.Branson, H., 25.Brasch, A., 69.Brasted, R. C., 315, 362.Braude, E. A.. 140,141,170,Braun, B. H., 250.Braunitzer, G., 273.Bray, R. H., 341, 342.Breck, D. W., 107.Breckenridge, J. G., 158.Breddy, L. J., 192.Bredereck, H., 175,237,254.Brenner, J., 146.Brenner, M., 280.Breslauer, H., 205.Breslow, R., 208.Bretscher, E., 28.Bretschneider, G., 352.Sreuer, H., 364.Breusch, F. L., 313, 314.Brewer, C. R., 255.Brewer, L., 31, 89.Brewer, P. I., 351.Breyer, B., 361.Brice, T. J., 187.Bricker, C. E., 341, 360,Brieskorn, C. H., 214.Briggs, L. H., 195, 243.Briggs, R. M., 361.Bright, H.A., 338.Brilkina, T. G., 98.Brill, N. F., 131.Brin, G. B., 331.Brindley, R. A., 156.Briner, E., 65, 170.Brink, N. G., 270.Bristow, G. M., 62.Britton, H. T. S., 75.Broadbank, R. W. C., 359.Brocklehurst, B., 46.Brockman, P. E., 234.Brockmann, H., 181, 194.314, 316.192.365.Broida, H. P., 23.Brmsted, J. N., 87.Brook, A. G., 364.Brooks, E. J., 370.Brooks, F. R., 357.Brooks, J. W., 214.Brossi, A., 214.Brous, G. C., 79.Brown, B. R., 238.Brown, C. J.. 154.Brown, D. D.,.54.Brown, D. J., 240.Brown, D. M., 245.Brown, E. G., 341, 344, 351.Brown, E. V., 158.Brown, F., 136,334.Brown, F. E., 344.Brown, G. B., 244.Brown, G. W., 315,316.Brown, H. A., 187.Brown, H. C., 95,96, 97,113,125, 126, 131, 133, 169,239.Brown, J.A., 371,373.Brown, J . F., 99.Brown, J . F., jun,, 142.Brown, J. J., 171.Brown, J. K., 12.Brown, M., 138.Brown, R. D., 125.Brown, R. F., 233.Browne, A. W., 50.Bruce, D. B., 198.Brucer, M., 63.Bruckner, V., 276.Bruhn, J., 10.Brundin, R. H., 350.Brunings, K. J., 201.Brunisholz, G., 340.Brunner, M. P., 223.Bruns, I., 111.Bruschweiler, H., 361.Bryant, B. E., 91.Bryant, F. J., 360.Bryson, A., 384, 353, 359.Buchanan, J., 37, 327.Buchanan, J. M., 313, 314.Bucher, N. L. R., 309.Buchert, A. R., 271.Buchi, G., 192.Buchwald, H., 372.Buckley, G. D., 12.Budde, G., 194.Budde, M., 359.Bueche, A. M., 66.Biichi, G., 214.Buehler, R. J., 81.Buell, M. V., 297.Buttner, F., 205.Buff, F. P., 72.Buist, G.J., 149.Bull, H. B., 274.Bull, J. P., 371.Bu’Lock, J. D., 177.Bultman. T. D., 374.Bunnett,. j. F., 128, 143,156INDEX OF AUTHORS’ NAMES. 383Bunton, C. A., 50, 64, 120,127, 143, 149.Rurawoy, A., 178.Rurbank, R. D., 11.Burchinskaya, N. B., 362.Burg, A. B., 95, 106.Burgard, A., 233.Burger, A., 241.Burgers, W. G., 72.Rurgstahler, A. W., 235.Burkhalter, T. S., 349.Burkhardt, H. J., 105.Burma, D. P., 370, 374, 375Burnelle, L., 20.Burnett, G. M., 58, 59, 60.Burnside, C. H., 233.Burr, J . G., jun., 137.Uurriel-Marti, F., 350, 364Burrows, S., 214, 255.Burrus, C. A., 11, 12.Burton, H., 93.Burton, H. S., 374.Burton, M., 65.Burton, W. R., 17.Rusch, D. H., 119, 340.Busey, R. H., 32.Busnel, R.G., 245.Busset, M. B., 13.Butler, E. J . , 366.Rutterworth, I. S . C., 363.Buttery, R. G., 145, 199,Butts, J. S., 315, 317, 320.By&, J., 92.Byrd, C. H., 337, 366.Bywood, R., 330.Cabannes, J., 18.Cabell, M. J., 90, 340.Cadotte, J. E., 264, 266.Cady, G. H., 113.Cagle, F. W., 159.Caldas, A., 345, 348.Caldas, E. F., 358.Calderwood, R. C., 182.Caldin, E. F., 55.Caldwell, M. L., 288, 294,Calero, A., 212.Calero, R., 212.Caley, E. R., 348, 350.Callomon, H. J., 16, 114.Calmon, C., 372.Calvert, J. G., 44.Calvin, M., 57, 317.Cama, H. R., 178.Camenisch, K., 233.Camerino, B., 278.Cameron, A. F. B., 168.Cameron, M. C., 322.Cameron, M. I?., 280.Campaigne, E., 174.Campanaro, L., 195.Campbell, A., 157, 208.Campbell, A.D., 355.365.200.Buu-Ho~, Ng. Ph., 190.295, 296.Campbell, B. K., 233.Campbell, J . E., 155.Campbell, K. N., 233.Campbell, M. E., 339.Campbell, N . , 163, 188, 190Campbell, R. A., 74.Cannon, C. G., 363.Cantoni, G. L., 244.Capp, C. W., 145.Capps, D. B., 237.Capuano, L., 214.Caraway, W. T., 149.Carberry, J . J., 37.Carbonne, G., 356.Cardon, €3. P., 318.Cardwell, H. M. E., 219.Careri, G., 36, 81.Carini, F. I?., 340.Carlesmith, L. A., 129.Carlquist, B., 296.Caron, E. L., 241.Caron, M., 376.Carr, E. M., 145, 352.Carriel, J . T., 116.Carrington, H. C., 238.Carrington, T., 34.Carrington, T. R., 283, 287Carruthers, W., 190.Carson, A. S., 26.Carson, E. M., 26.Carson, S. F., 318.Carson, W. N., 360.Carsten, M.E., 273.Carter, H. E., 184, 185, 186Cartledge, G. H., 91.Casanova, R., 227.Cason, J., 172, 173, 174, 183Cassidy, H. G., 378.Castaing, R., 370.Castle, R. N., 370.Castor, W. S., 107.Catchpole, A. G., 140.Cathey, W. J., 310.Caunt, A. D., 21, 22, 27.Cavalieri, L. F., 245.Cave, G. C. B., 83.Cavell, E. A. S., 129, 371.Celmer, W. D., 177, 238.Cerney, R. R., 368.Chabasse-Massonneau, J.,Chaberek, S., 91, 340, 343.Chadderton, J ., 243.Chadwiclc, J., 130.Chaikoff, 1. L., 232, 309,310, 311, 313, 314, 316.Zhakraburtty, A. K., 91.Zhakravarti, D., 252.Zhakravarti, R. N., 252.Zhakravarti, S. C . , 252.Shallenger, F., 236, 330.Zhalmers, R. A, 347, 345,Zhamberlin, E. M., 170, 225.Zhambers, M. A., 372.199.277, 320.248.363.Chambers, T.S., 39Chambers, V. C., 13Chambon, M., 358.Chanda, S. K., 325,Chang, L. T., 371.Chang, N., 245.329.Chaniey, J . D., 168.Clianmugam, J.. 43.Channing, D. M., 330.Chapiro, A., 65, 66.Chapman, D. D., 313.Chapman, J . I-I., 168.Chapman, N. B., 129, 371.Chapon, S., 211, 215.Chaput, E. P., 233.Charlesby, A., 66.Charlot, G., 362, 368.Charlton, J . C., 136.Charnley, T., 28, 107.Chase, B. H., 171, 240.Chasson, D., 365.Chateau, H., 376.Chatt, J., 121, 122.Chatterjee, A., 252.Chaudhuri, D. I<. R., 166,Chaudron, G., 376.Chauvet, J., 26s.Cheldelin, V. H., 315.Chemerda, J , M., 169, 170,Chen, M. C., 187.Chen, P. S., 368.Chen, R. W., 313.Cheng, K. L., 341, 342.Cheniae, G.M., 256.Chernick, S. S., 309, 310.Chibnall, A. C., 182.Childs, W. H. J., 9.Chilton, H. T. J., 26, 41, 42.Chilton, J. M., 364.Cliinn, L. J., 175.Cliisholm, D. A., 14.Chmiel, C. T., 42, 40.Cholnoky, L., 180.Chou, T. C., 303.Chow, D. T., 361, 364.Christensen, H. N., 275.Christensen, V. J., 116.Christian, J . E., 375.Christie, M. I., 38.Christie, S. M. H., 245.Christman, D. R., 245.Chu, J. C., 65.Chung, D., 279, 375.Chupka, W. A., 31, 101.Chynoweth, A. G., 87.Ciereszko, L. S., 137.Cimerman, C., 353, 364.Clapp, L. B., 238.Clar, E., 191.Clark, D., 99.Clark, G. C., 343.Clark, R. F., 187.Clark, S. J,, 342, 358.Clarke, €3. T., 330.Clarke, J. T.. 32, 69.258.2253 84 INDEX OF AUTHORS' NAMES.Clarke, R.S., 121.Clark-Lewis, J . W., 240.Clauser, H., 268.Claycomb, C. K., 310.Clayton, R. B., 225, 230.Clemency, C., 339.Clement, R., 174.C.lements, G. C., 240.Clements, L. M., 367.Clemo, G. R., 165, 188, 196,Cleveland, E. A., 263.Cleveland, F. C., 289, 292,Cleveland, F. F., 12.Cleveland, J. H., 263.Clifford, A. F., 114, 377.Close, W. J., 241.Clough, J., 376.Clusius, K., 200.Coates, G. E., 100.Cochran, W., 245.Cocker, W., 210.Codell, M., 339, 365, 366.Coderre, R. A., 175.Coderre, R. C., 175, 202.Coffey, S., 194.Cohen, A., 250.Cohen, L. A., 175.Cohen, M., 151.Cohen, P. P., 313.Cohen, S. G., 58.Cohn, H., 125.Cohn, W. E., 245, 256.Coillet, D. W., 41.Cole, A. R. H., 211.Coleman, J. E., 147.Coles, D. K., 9, 10.Coles, J.A., 141.Colichman, E. L., 361.Colin, H., 326.Colingsworth, D. R., 223.Collier, R. E., 362.Collins, C. J., 56, 137, 138.Collins, R. L., 12.Collinson, E., 66.Colonge, J., 176.Colvin, J., 73.Colvin, J. R., 328.Comyns, A. E., 143.Conchie, J ., 324.Coniglio, J. G., 310.Conix, A., 59.Conn, E. C., 150.Connally, R. E., 375.Connell, J. J., 323.Connick, R. E., 48, 113.Conover, L. H., 201.Conroy, H., 197.Consden, R., 256.Cook, A. H., 334.Cook, C. D., 148, 152.Cook, D., 83.Cook, J. W., 154, 155, 188,189, 190.Cook, M., 316.208, 241.296, 300.Cook, N. c., 175.Cook, P. L., 233.Cook, R. J., 46.Cook, W. B., 369.Cook, W. H., 328.Cooke, N. J., 182.Cooke, W. D., 116, 361.Cookson, G. H., 234.Cookson, R.C., 166, 249.Coon, M. J., 306, 315, 320,Cooper, G. D., 131.Cooper, H. C., 148.Cooper, H. R., 46.Cooper, J. A., 73.Cooper, K. A., 141.Cooper, R. L., 188, 368.Cooper, W., 57, 60.Coops, J., 30.Cope, A. C., 203.Copeland, L. C., 24.Copp, J. L., 88.Corbett, J. A., 373.Corbett, J. D., 99.Corbett, R. E., 105.Corbett, W. M., 171.Cordner, J. P., 149.Cordts, H. P., 233.Corenzwit, E., 370.Corey, E. J., 203, 218.Corey, R. B., 339.Cori, C. F., 290.Cori, G. T., 290, 297.Cori, O., 313.Coriou, H., 359.Cornforth, J. W., 219, 226,Cornhill, W. J., 322, 323,Cornwell, C. D., 19.Corse, J., 135, 136.Corwin, A. H., 234,Cosgrove, L. A, 30, 93.Cosgrove, L. H., 32.Cosgrove, S. L., 146, 149.Cottin, M., 70.Cotton, F.A., 118.Couch, D. A., 263.Coulson, C. A., 125, 130,Coulson, C. B., 330.Coulter, L. V., 30, 93.Courtney, R. C., 91, 340,Cousin, B., 357.Covo, G. A., 301.Cowan, G. R., 23, 34, 39.Cowan, J. C., 184.Cowan, S. T., 378.Cowdrey, W. A., 143.Cowley, P. R. E. J., 58.Cox, B. G., 25.Craig, L. C., 269, 271.Craig, P. N., 236.Craine, G. D., 12.Cram, D., 136.Cram, D. J., 137, 138, 159,321.231.324, 332.191.343.161, 162, 233.Cramer, F., 239.Cramer, F. B., 254, 259, 260.Crandall, D. I., 316.Crandall, L. A., 314.Crane, C. W., 146.Crane, K. F., 232.Crane, R. K., 312.Crawford, B., jun., 34, 39.Crawford, B. L., 13, 14, 16,Crawford, G. H., 114.Crawford, M., 158.Crawford, M. F., 13, 14.Crawford, V. A., 39, 130.Crawhall, J.C., 274.Crawshaw, A., 225.Cremer, E., 75.CremIyn, R. J . W., 229.Criegee, R., 146, 170.Cristol, S. J., 132, 133, 152.Crombie, L., 163, 201.Cron, M. J., 264.Cropper, F. R., 143, 371.Cross, B. E., 210.Cross, R. J., 301.Crowfoot Hodgkin, D., 219.Crowther, A. I?., 238.Croxatto, H., 269.Cruickshank, P. A., 175.Crummett, TV. B., 372.Cuendet, L. S., 256, 371.Culvenor, C. C., 239.Cumming, C., 9, 11.Cummins, R. W., 145.Cunningham, B. B., 30, 100,Cunningham, K. G., 261.Cunningham, L. W., 272.gunningham, M., 312, 319."upahin, O., 119.Curran, G. L., 314.Zurrey, A. S., 371.Curry, J . W., 194.Curtin, D. Y., 161.Curtis, R. G., 212.h r t i s s , C. F., 80, 81.Zurzon, G., 279, 375.k t l e r , C. H., 317.Sutter, H.B., 356.Zvetanovic, R. J . , 42.Daane, A. H., 100.Dacey, J. R., 45.Dagg, I. R., 13.Dailey, B. P., 10.Dain, B. Y., 51.Dainton, F. S., 61, 62, 66,Dakin, H. D., 302.Dale, J., 180.Dale, J. W., 111.Dalgliesh, C. E., 278.Dallwigk, E., 170.3al Nogare, S., 374.Danby, C. J., 30.Danehy, J. P., 264.Daniels, F., 28, 39, 56, 64.23.354.67, 68INDEX OF AUTHORS’ NAMES. 385Daniels, R., 221.Danz, H., 358.Darling, B. T., 10.Darling, L. H., 202.Darnell, A. J., 27.Darwent, B. de B., 41, 45.Das, Wl. N., 354.Das Gupta, A. K., 354, 361,Dauben, G., 169.Dauben, W. G., 160, 167,206, 210, 230, 232, 314,316.364.Daus, L., 317.Davenport, D. A., 105.Davey, D. G., 238.David, S., 211, 215.Davidson, A. W., 116.Davidson, N., 34, 38, 95,Davie, E.W., 274.Davies, A. G., 145.Davies, C. W., 355.Davies, M., 15, 57.Davis, B. M., 145.Davis, H. M., 360.Davis, N. R., 54, 55.Davis, R., 161.Davis, R. E., 111.Davis, W., jun., 32.Davison, S., 64.Davison, W. H. T., 14, 15.Davoll, J., 234.Dawson, G. Q., 104.Dawson, H. M., 142.Dawson, J . K., 112.Dawson, J . V., 376.Dawson, M. C., 213.Dawson, R. F., 245.Day, A. R., 150.Dayton, J. C., 50.Dayton, R. P., 188.De, A. K., 348.Dean, J. -4., 365, 371.Dean, R. A., 164, 202.Deatherage, F. E., 171.Debo, A., 117.DeBusk, B. G., 238.Decius, J. C., 14.Decker, C. E., 12.Dedonder, R., 282, 283.Deemer, L. F., 181.Deferrari, J . O., 262.DeFord, D. D., 361.Degenhart, V., 65.Deijs, W.B., 365.Deitz, V. R., 363.de Jong, J. I., 359.De Keyser, W. L., 346.Delahay, P., 360.De la Mare, H. E., 134.de la Mare, P. B. D., 127,128, 129, 130, 131, 132,139, 141.119.Delande, N., 356.Delavault, R., 354.Delbecq, C. J., 376.REP.-VOL. Ldel Campillo, L4., 302, 303,Delhaye, M., 13.Deliwala, C. W., 253.Delsemme, A., 20.Delwaulle, M. L., 13.Delwiche, E. A., 318.de Mayo, P., 214.De Ment, J., 355.Demmler, A., 361.Demmler, K., 158.DeMore, W., 12.Denbigh, K. G., 19.Denes, G., 276.DenHertog, H. J., 239.Denigks, G., 329.Denk, G., 354.Denney, D. B., 164, 202.Dennison, D. H., 100.Dennison, D. M., 13.Dennison, D. N., 10.De Puy, C. H., 192.Derbyshire, D. H., 128.Derfer, J . M., 201.DeSesa, M. A., 361.Deshmukh, G.S., 347, 349.Deshpande, S. M., 65.Desmyter, A., 84, 86.Desnuelle, P., 273, 274.de Sousa, A4., 340, 342,Detar, D. F., 58.Detilleux, E., 147.Deuel, H., 254, 367.Deuel, H. J., 312, 315, 317.Deulofeu, V., 262.Deutsch, A. S., 169.Deutschman, J., 362.de Villiers, J. P., 173, 181.Devonshire, A. F., 80.DeVries, R. C., 113.Dewald, W., 336.Dewan, J. G., 306.Dewar, E. T., 322, 323, 324,Dewar, M. J. S., 122, 125,de Whalley, H. C. S., 254,Dewhurst, H. A., 68.dc Witt, H. D., 158.Dhar, S. K., 354, 364.Diamond, J , J., 368.Dibeler, V. H., 25, 61.Dickel, D. F., 160, 210.Dickens, F., 301.Dickey, E. E., 374.Dickman, S. R., 273.Diederichsen, J., 197.Diehl, H. W., 260.Dienske, J. W., 30.Dierichs, W., 173.Dietar, W.E., 116.Dillaha, J., 275.Diller, H., 374.Dillon, T., 292, 324, 327,306.345.327.126, 139.286.328, 329.Dilts, R. V., 360.Dilz, K., 239.di Modica, G., 371.Dimroth, K., 240.Dinkel, P., 280.Dinnin, J. I., 366.Dinsmore, H. L., 16.Dirkse, T. P., 364.Discherl, W., 364.Disse, W., 359.Ditter, J., 107.Dittmer, D. C., 135.Dittride, W., 69.Dituri, F., 309.Djerassi, C., 169, 171, 210,215, 218, 226, 227, 230,249.Dmitrievskaya, N. V., 294.Doan, M., 364.Dobek, G., 100.Dobriner, K., 17, 218, 232.Dobytshin, D. B., 76.Dodson, R. M., 227.Dodson, R. W., 101.Doring, W., 71.Doering, W. von E., 134,135, 150, 192.Doescher, R. N., 21, 27.Doggant, J. R., 53.Doherty, D. G., 245, 265.Domgorgen, H., 356.Dominguez, J .A., 217.Donaldson, D. M., 154.Dondes, S., 65.Donnelly, D. M., 243.Doone, R., 242.Doorenbos, N. J.. 203.Dorfman, A., 256.Dorfman, L., 249.Dorfman, L. M., 65.Dornow, A., 169.Doser, H., 236.Dost, N., 148.Dostrovsky, I., 132, 136.Doudoroff, M., 287, 298,Doughty, M. A., 143.Douglas, A. E., 12, 23.Douglas, B. E., 91, 340.Douglass, R. M., 369.Doumanis, G. C., 11, 12.Dowling, E. J., 374.Downes, A. M., 56, 240.Downie, A., 39.Drake, M. P., 270, 275.Draper, F., jun., 128, 249,Dreiding, A. S., 167, 172,Dresel, E. I. B., 234.Drisko, R. W., 255.Drucker, B., 276.Drummond, A. Y., 53, 115,Drummond, G., 22, 29.Drysdale, G. R., 302.Dubbs, C. A., 377.306.252.228.150, 151, 359.386 INDEX OF AUTHORS' NAMES.Dubraveid, M., 377.Duchesne, J ., 20.Duff, R.B., 256, 371.Duff, S. R., 210, 219.Dufrenoy, J., 335.Duke, F. R., 51, 53, 150.Dulberg, J., 255.Dulce Almeida, M., 363.Dulou, R., 205.Dunbar, J. E.: 148.Duncan, G. D., 377.Duncan, G. G., 314.Duncan, R. E. B., 374.Duncanson, L. A., 12, 14,Dunham, J. L., 16.Dunitz, J. D., 13.Dunn, J . R., 148.Dunn, M. S., 320.Dunstan, I., 243.Dupont, G., 205, 215.DuPr6, E . F., 182.Dupuis, T., 348.Durham, R. W., 41.Durie, R. A., 23.Durr, G., 171.Dursch, H. R., 266.Durso, D. F., 256.Dustin, J. P., 372.Du Temple, O., 373.Duval, C., 339, 346, 364.du Vigneaud, V., 268, 269.Duxbury, F. K., 196.Duycltaerts, G., 342, 362.Dvonch, TV., 289.Dwyer, F. P., 54, 55, 119,Dyne, P.J., 44.Eastham, J. F., 167, 169,Eastman, R. H., 205.Easton, J . D., 215.Easton, N. R., 233, 236.Easty, D. M., 131, 134.Easty, 6. C., 156.Eaton, D. C., 225.Ebel, F., 28.Eberhardt, G., 167.Eberhardt, H.-D., 242.Ebert, M., 65.Eddy, C. R., 147, 232.Edelman, I., 282, 283, 284,285, 286, 287.Edelson, D., 14.Edgell, W. F., 12.Edman, P., 275.Edson, N. L., 312.Edward, J. T., 210,254,274.Edwards, J., 76.Edwards, W. G. H., 372.Eeckhout, J., 355, 365.Egerton, M. J., 184.Eggleston, L. V., 313, 314.Egle, K., 234, 332.Eglinton, G., 176.Ehni, G. J., 314.122.121.230.Ehrenthal, I., 263.Ehrhart, G., 278.Eigen, I., 167.Eilar, K. R., 133, 152.Eipeltauer, E., 353.Eisen, H. N., 273.Eisenschitz, R., 80.Eisler, B., 55.Eisner, U., 174.El-Radry, H.M., 338, 344El-Din Zayan, S., 112.Eldjarn, L., 302.Elhafez, F. A. A., 137, 152Eliel, E. L., 138.Elkind, A., 366.Elkind, M. J., 361.Elks, J., 224.Elliott, D. F., 274.Elliott, W. W., 99.Ellis, G. H., 377.Ellis, G. P., 262, 263.Ellis, K. W., 365.Elming, N., 253.Elmore, D. T., 245, 275.Elovich, S., 78.El-Shamy, H. K., 112, 114Elsner, R. B., 167.Elson, R. E., 107.Elston, C. T., 174, 199.Elvey, C. T., 22.Elvidge, J. A., 174,186,334.Elving, P. J., 346.Ely, J . O., 259.Elyash, E. S., 9.Elzas, M., 321.Embden, G., 312, 320.EmelCus, H. J., 102, 114Zmerman, S. L., 192.Zmerson, K., 120, 340.Zmmons, W. D., 171, 199.Zmmrich, R., 319, 321, 322.Zmmrich-Glaser, I., 32 1,kgelbrecht, L., 106, 109.Zngland, B.D., 138.Znglard, S., 291.Snglish, W. D., 111.Sntenman, C., 314.Zppstein, S. H., 222, 223.Zrdey, L., 355.Zrgener, L., 242.Srickson, J . G., 262.Crickson, R. L., 170, 225.Cricson, L.-E., 333.Criksson, -4. F. V., 62.Srlenmayer, H., 237.Srlenmeyer, H., 374.kne, M., 237.Srofeev, B. V., 72, 76, 77.Crspamer, V., 237.Sschenmoser, A., 205, 208.kin, 0. A., 75.Gstes, B. T., 364.Sstill, W. E., 120.377.161.187.322.Estremera, H., 330.Etienne, H., 336.Ettorre, R., 217.Eugster, C. H., 178, 179.Evans, A. G., 140.Evans, D. D., 230.Evans, D. F., 148.Evans, E. A., 49, 170, 375.Evans, H. M., 270.Evans, J. C., 15.Evans, M. G., 22, 24, 27.Evans, P., 59.Evans, R. M., 168, 224, 238.Everest, D.A., 361.Everett, D. H., 86, 88.Evertzen, A., 271.Evstigneev, V. B., 331.Evstigneeva, R. P., 247.Eyring, H., 36, 47, 48, 130,Eyring, L., 30.Eysell, K., 359.Eysenbach, H., 305.Ezrin, M., 378.Faber, A. C., 30.Faber, R., 364.Fabre, C., 272, 273, 274.Fagley, T. F., 30.Fairbairn, N. J., 254.Fairbrother, F., 99.Fairburn, E. I., 244.Fairlie, A. M., 37.Fales, H. M., 240.Falk, J . E., 234.Fall, W., 362.Fallab, S., 374.Faller, F. E., 341.Fankuchen, I., 370.Fantl, P., 312.Faqueret, M., 75.Farber, M., 27.Farenhorst, E., 42.Farina, P. E. L., 365.Farmer, E. C., 66.Farrar, M. W., 219.Farrington, P. S., 359, 360.Fasman, G. D., 245.Fassel, V. A., 368.Faulkner, I. J., 142.Fava, A., 49.Favre, C., 198, 206.Fawcett, J.S., 141, 211.Fawcett, R. W., 208.Feast, M., 22.Fedoseeva, A. I., 110.FehCr, F., 110.Peigl, F., 336, 344, 345, 348,'eldman, J., 188.Teldmeijer, J. H., 365.Selix, K., 273.?ellig, J., 284.Teltham, R., 366.?elts, J. RT., 309, 310, 311.Zenner, J. V., 187.Fenton, S. W., 203.159.352INDEX OF AUTHORS’ NAMES. 387Ferguson, E., 14.Ferguson, E. E., 12.Ferguson, G. W., 280.Ferguson, R. C., 12.Ferigle, S. M., 12.FernAndez Caldas, E., 364.Fernando, Q., 371.Fernelius, W. C., 91, 340.Ferraro, L., 30.Ferreira, R. C., 378.Ferretti, R. J., 367.Ferris, A. F., 171, 199.Fetizon, M., 356.Fevell, A. J., 358.Fialkov, Y. A., 350.Ficke, B., 105.Fickett, W., 153.Field, A. C., 178.Field, F. H., 33, 36.Fierce, W.L., 270.Fierens, P. J. C., 131.Fieser, L. F., 164, 210, 217,218,226,229,232.Fieser, M., 210.Filippova, K. V., 372.Fill, M. A., 339.Filler, R., 187.Fillet, P., 47.Finch, A., 73, 76.Findlay, S. P., 165, 166.Finestone, A. B., 39.Finholt, A. E., 95, 96.Fink, K., 303.Fink, R. M., 303.Finke, H. L., 32, 233.Finkel, A. G., 39.Finkelstein, A., 47.Finnegan, TV. G., 238Finnerty, J., 270.Firestone, R. A., 197.Fischbeck, K., 80.Fischer, E., 157, 163, 256.Fischer, E. H., 284, 288,291, 294, 298.Fischer, E. O., 116, 118.Fischer, F. G., 305.Fischer, H. 0. L., 266.Fischer, J., 317.Fischer, K., 106.Fischer, R., 356.Fischer, K. B., 347.Fish, V. B., 233, 236.Fisher, C., 376.Fisher, E., 364.Fisher, G.J., 176.Fisher, H. V., 150.Fisher, J. C., 71.Fisher, K., 205.Fix, D. D., 132.Flaschentrager, B., 322.Flaschka, H., 341, 342, 353.Fleishman, D. M., 349.Fletcher, E., 255, 375.Fletcher, H. G., 168.Fletcher, H. G., jun., 259,Fletcher, R. S., 131.260.Flett, M. St. C., 14.Floc’h, A., 171.Flood, H., 75.Floumoy, J. M., 50.Floyd, N. F., 302, 313.Flynn, R. M., 303, 304.Fock, W., 88.Fodor, G., 164, 165, 166,Foering, L., 40.Fogg, G. E., 336.Fok, N. V., 46.Folkers, K., 270.Folley, S. J., 309.Fones, W. A., 320.Fones, W. S., 157, 277, 278.Fong, J., 363.Fonken, G. S., 223.Fontijn, A., 49.Forbes, E. J., 251.Forbes, J. W., 249.Forbes, W. F., 170, 192.Ford, J . J., 354.Forrest, J., 146.Forster, W. A., 341, 342,Foster, A.B., 256, 257, 263,Foster, D. G., 354, 359.Foster, L. S., 376.Foster, R. V., 145.Fournier, P., 210.Fowler, L., 45.Fowles, G. W. A., 103, 107.Fox, J. J., 17, 245.Fox, S. W., 277.Fraenkel, G., 56.Frankel, H., 118.Fraenkel-Conrat, H., 273,Fraga, D., 88.Francis, S. A., 17.Francotte, C., 356.Frank, A. J., 120.Frank, F. C., 71.Frank, G., 110.Frank, S., 133.Franke, A. A., 372.Franke, G., 146, 170.Franke, W., 178.Frankel, M., 278.Frankenburg, P. E., 47.Frank-Frederic, S., 374.Franklin, J . L., 33, 36, 140.Franzen, F., 359.Fraser, D., 367.Fraser, R. D. B., 17.Frauenfelder, L. J., 358.Frazer, W., 203.Freak, G. R., 870.Freamo, M., 105.Frech, M. F., 37.Fredga, A., 219.Freedman, E., 34.Freeman, G.R., 64.Freeman, J. P., 138.Freeman, N. K., 15, 183.185.365.265, 375.274.Frei, Y. F., 143.Freiling, E. C., 342.Freiser, H., 340, 348, 373.French, C. S., 331.French, D., 255, 288, 292,French, J., 369.French, T. H., 309.Frenkel, J., 72, 82.Freudenthal, P., 332.Freund, H., 366, 372.Freund, T., 107.Freundlich, H. F.. 64.Frey, F. W., 119.Frey, H., 226.Fricker, D. J., 362.Fridrichsons, J . , 21 1.Fried, J., 223, 228, 252, 264.Fried, S., 113.Friedel, R. A., 11i.Friedkin, M., 308.Friedman, B., 312.Friedman, H., 370.Friedman, L., 40, 57.Friedman, L. J., 235.Friei, R., 261.Friess, S. L., 266.Frisch, D. M., 237.Fristrom, R. M., 12.Frith, W. C., 99.Fritsch, F. E., 326.Fritz, G., 102.Fritz, H.E., 104.Fritz, J . J., 354.Fritz, J. S., 359, 377.Friz, H., 27.Fromageot, C., 274.Fromageot, P., 268.Fronaeus, S., 120.Frost, G. B., 74.Frostick, F. C., 175.Fruton, J. S., 279.Fry, A., 57.Fryth, P. M7., 265.Fuchs, E., 277.Furst, A., 208, 227, 232.Fugmann, R., 215.Fujino, Y., 185.Fujita, H., 82.Fuliushima, D. K., 213.Fuld, M., 289.Fulda, M. O., 377.Fulmer, R. E., 349.Funioto, T., 328.Funck, D. L., 152.Furman, N. H., 360, 361.Furutani, S., 281.Fuson, N., 14.Fuwa, H., 294.Gabrielson, G., 372.Gadamer, J., 236.Gaertner, P., 363.Gagliardi, E., 349, 355.Gailar, N., 12.Gaillard, B. D. E., 255, 374.296,297.Fu, S.-C. J., 157388Gal, O., 112.Galan, M., 376.Galfk, V., 210.Gall, H., 117.Gallagher, G.A., 100,Gallagher, K. M., 243.Gallagher, T. F., 169.Gallagher, T. K., 213.Gallay, 2. A., 362.Gallego, R., 365.Gamlen, G. A., 119, 365.Ganguli, N. C., 375.Gantmakher, A. R., 62.Garbers, C. F., 178, 179.Garbrecht, W. L., 239.Gardell, S., 256, 374.Gardiner, K. W., 360.Gardner, G. M., 335.Garforth, F. M., 20.Garibaldi, J. A., 297.Garikian, G., 84.Garlow, K. Y., 356.Garmaise, D. L., 229.Garner, F. H., 147.Garner, H. K., 153.Garner, W. E., 70, 72, 73Garnett, J. L., 345.Garritt, D. E., 371.Garschagen, H., 363, 364,Gascoigne, R. M., 212, 213.Gassner, I<., 358.Gastinger, E., 348.Gaudemar, M., 176.Gauguin, R., 360, 362.Gauhe, A., 264.Gaunt, J., 13.Gavard, R., 290.Gavrilova, V. A., 331.Gaydon, A. G., 23, 28.Gayer, K. H., 361, 366.Gebauhr, W., 347.Gebert, E., 370.Gedda, K., 373.Gee, A., 363.Gee, M., 316.Gehman, H., 288.Geiger, R.W., 373.Geilmann, W., 347, 352.Geisler, A. H., 71.Geissman, T. A., 207, 368.Gel’d, P. V., 75.Gelin, R., 176.Geller, L. E., 215.Geller, S., 370.Gelles, E., 14.Gelles, T. S., 56.Gemmill, C. L., 315.Genas, M., 278.Genzer, J. D., 278.Gerdes, G., 332.Gerding, H., 100.Gerds, A. F., 376.Gergel, M. V., 373.Gerhardt, L. S., 140.Gerold, C., 229.74, 78, 79.367.INDEX OF AUTHORS’ NAMEGeschke, P., 203.Geschwind, S., 19.Geyer, R. P., 301, 312, 313,314, 319.Ghormley, J . A., 64.Ghosh, B., 74.Ghosh, N. N., 91.Ghosh, S., 53.Ghosh, S . N., 10, 11.Giauque, W. F., 27, 32, 105,Gibb, T.R. P., 112.Gibbons, D., 347, 354.Gibbons, G. C., 288.Gibson, D. T., 154, 188.Gibson, N. A., 365.Gierlinger, W., 364.Gilbert, G. A., 289, 298.Gilbert, J. H., 308.Gilbreath, J. R., 95, 96.Gilchrist, R., 339.Gil’dengershel, K. I., 121.Gill, N. S., 119.Gill, R. A., 339.Gilles, P. W., 21, 27, 360.Gillespie, R. J., 110, 126.Gilliam, 0. R., 10.Gillis, J., 344, 345, 365.Gilman, H., 104, 123.Giltrow, J., 279, 375.Gilvarg, C., 313.Ginger, L. G., 183.Gingold, K., 103.Gingras, B., 42.Ginsberg, H., 99.Ginsburg, D., 170, 218,Giri, K. V., 373.Gjems, O., 341, 362.Gladner, J. A., 274.Gladshtein, B. M., 201.Glamm, A. C., 361.Glasner, A., 78.Glasscock, R. F., 309.Glasson, D. R., 80, 94.Glastonbury, H. A., 362.Glazer, H., 144.Glazier, R. H., 107.Glemser, O., 115, 366.Glendenin, L.E., 376.Glenn, R. A., 362.Glick, G., 338.Glockler, G., 10, 28, 32.Glos, M., 242.Glover, J., 178.Gnaedinger, A. W., 373.Gnauck, B., 154.Goebel, A.. 101.Goeckerman, R. H., 66.Goehring, M., 109, 11 7.Goerdler, J., 356.Goering, 13. L., 136, 139,164,202.Goffart, J., 342.Gold, V., 126.Goldblith, S. A., 64.Golden, H. R., 202.110.243Golden, S., 36.Goldman, D., 307.Goldman, D. S., 305, 307,314, 315, 316.Goldring, L. S., 363.Goldschmidt, S., 279.Goldstein, J. H., 12.Gompf, T. E., 215.Gonikberg, M. G., 57.Gonon, W. F., 295.Gonzalez, G. A., 212.Good, W. D., 32.Good, TV. E., 10.Goodban, A. E., 372.Gooderham, W. J., 376.Goodwin, S., 249.Goodwin, S.M., 147.Goodwin, T. W., 334.Goon, E., 367.Gordon, J., 27.Gordon, L., 342, 346, 347,Gordon, M., 130.Gordon, N. E., 367.Gordon, P. N., 201.Gordon, S., 268.Gordy, W., 9, 10, 11, 12,Gorin, E., 130.Gorin, P. A. J,, 260, 261,Gorman, J. G., 9.Gorman, M., 249.G6rski, A., 374.Gosselin, K., 106.Gossen, W., 364.GotB, H., 347, 378.Gots, J. S., 237.Gottschal, A. J., 32.Goubeau, J., 97, 101, 102.Could, C. W., 370.Goulden, J. D. S., 14.Goulden, R., 351.Goutarel, R., 248, 249.Gouverneur, P., 357.Govindachari, T. R., 246.Gowenlock, B. G., 26, 32,Grabar, D. G., 369.Graefe, A. F., 132.Graf, H., 98.Grafflin, A. L., 301.Gragson, J . T., 201.Graham, J. R., 199.Graham, R. P., 361.Graime, R., 53.Granick, S., 234, 330.Grant, D.K., 102.Graser, F., 205.Grassie, N., 58, 59, 61.Grassmann, W., 279.Graus, B., 91, 367.Graven, W. M., 42, 57.Gray, C. H., 234.Gray, J . A,, 45, 46.Gray, L. H., 65.Green, ,4. -4., 297.349, 362, 366, 372.28.267.39, 41, 42INDEX OF AUTHORS' NAMES. 389Green, D. E., 301, 302, 304,Green, F. C., 272.Green, H. S., 81.Green, J. H. S., 38.Green, N., 158.Green, R. W., 376.Greenbaum, A. L., 315.Greenberg, D. M., 320.Greenhalgh, C. W., 225.Greenlee, I<. W., 201.Greenstein, J . P., 157.Greenwood, C. T., 289, 200,Greenwood, F. L., 147.Greenwood, N. N., 97, 373.Gregg, R. A., 58.Gregg, S. J., 75, 80, 91.Gregorian, E. S., 76.Gregory, G. I., 185.Gregory, J. N., 376.Gregory, N.mT., 99.Gregory, T. M., 14.Grellmann, W., 321.Greville, G. D., 305.Grewe, R., 242.Griffith, C. B., 376.Griffith, R. L., 76.Grigg, J . L., 365.Grim, L. I., 356.Grimaldi, F. S., 366.Grinberg, A. A., 49.Grisard, J. W., 89.Grob, C. A., 168, 170, 186,233, 234.Groeneveld, W. L., 107.Groh, H. J., 44.Grogan, C. H., 168.Groocock, J . M., 79.Gropp, A. H., 15.Gross, D., 256, 285, 374,Gross, J., 276.Gross, M. E., 32, 233.Gross, S. T., 370.Grosse, A. v., 116.Grove, J. F., 190.Grovenstein, E., 133.Gruber, ?V., 236.Gruen, D. M., 113.Griitter, H., 205.Grummitt, O., 138.Grunbaum, B. W., 350, 362.Grundman, C., 175, 180,Grunwald, E., 135, 136.Grylls, F. S. M., 255.Gubguen, E., 326.Giinthard, 13. H., 173, 232.Guest, R.J., 365.Guggenheim, E. A., 80, 53,Guider, J. M., 211.Guinier, A., 71, 370.Gullikson, C. W., 12.Gullstrom, D. K., 364.Gumb, J., 195.305, 306, 307, 312.300, 362.375.241.86.Gunning, H. E., 46.Gunsalus, I . C.. 238.Gunstone, F. D., 182.Gunthard, H . H., 149.Gunton, M., 340.Gurevich, E., 74.Gurin, S., 308, 309, 310,313, 314, 316, 320.Gur'yanova, E. N., 49.Gusev, H. I., 349.Guss, C. O., 233.Gutsell, E. S., 223.GJyot, H., 358.Gwinn, W. D., 12, 15, 201.Gyarfas, E. C., 119, 121.Gysel, H., 346.Haarmann, W., 31;.Haas, C. G., 91, 340.Haas, P., 326.Haase, L., 101.Hachihama, Y., 60.Hackley, €3. E., 271.Hackstein, K,-G., 359, 367.Haendler, H . M., 104, 107.Hafner, W., 118.Hages, N., 280.Haggis, G.A., 164, 202.Hagihsra, B., 294.Hagiwara, Z., 355.Hahn, A., 317.Hahn, F. L., 353.I-Iahn, H., 110.Hahn, R. B., 341, 359, 372.Haider, S. Z., 353.Haigh, C. P., 376.Haight, G. P., 348, 351.Hailes, H. R., 72.Haines, W. J., 223.Hainsworth, R., 276.Haissinsky, M., 69, 70.Hale, D. K., 372.Hale, E. E., 343.EIalevi, E. A., 50, 127.Hall, A., 367.Hall, D. M., 156.Hall, D. R., 155.Hall, F. M., 362.Hall, J. L., 92.Hall, W. I<., 116.Hallman, L., 315.Hallman, L. F., 317.Halmann, RI., 14, 132.Hals, J . D., 187.Hals, L. J., 187.Halsall, T. G., 211, 212, 213,214, 215, 291, 293, 326.Halscy, J. T., 321.Hamann, R., 242.Hamann, S. D., 37, 140.Hamel, E. E., 277.Hamill, W. II., 42, 65.Hamilton, C. S., 237.Hamilton, J.K., 288, 323.Hamilton, M. B., 365.Hamilton, P. &I., 104.Hamilton, R. H., 363.Hamlet, J. C., 178, 238.Hamm, R. E., 111, 342.Hammer, C. F., 369.Hammett, L. P., 144, 171.Hammick, D. Ll., 238.Hammock, E. W., 354.Hammond, G. S., 127, 135,Hance, P. D., 206.Hancock, J. E. H., 201.Hanes, C. S., 279.Hannan, R. B., 12.I-Iannig, K., 270.Hanrahan, V. M., 294,295.Hansen, G. E., 13.Hansen, L., 12.Hansen, R. P., 182.Hansler, R. L., 11, 15.Kanson, F. R., 223.Hanze, A. R., 223, 244.Harborne, J. B., 243, 368.Hard, J. A., 259.Hardegger, E., 165.Harden, G. D., 38.Hardt, H . D., 93.Hardwick, T. J., 65, 69.Hare, G. H., 363.Haresnape, J. h-., 164, 202.Harfenist, E. J., 269, 271.Hargie, M. P., 177.Hargreaves, 8%. K., 153.Haring, H.G., 100.Harley, J . H., 363.Harley-Mason, J., 152, 251.Harms, D. L., 369.Harnick, M., 221.Harper, E. L., 376.Harper, S. H., 178.Harrap, B. S., 290.Harris, A. S., 188.Harris, C. M., 92.Harris, E. E., 161.Harris, E. F. P., 148.Harris, G., 286.Harris, G. M., 41.Harris, I., 77.Harris, J . I., 273, 274.Harris, J. O., 208.Harris, &I. M., 125.Harris, P. &I., 12.Harris, R. J. C., 245.Harrison, G. E., 364.Harrison, J. B., 185, 3 7 i .Harrison, J . S . , 255.Harrison, K. P., 305.Harrison, S. F., 82.Harrow, B., 342.Hart, F. L4., 122.Hartler, hT., 372.Hartley, K., 36.Hartman, J . A., 167.Hartmann, H., 100.Hartree, E. F., 362.Hartung, W. H., 165.IIarulrawa, T., 206.Harvey, A.E., 348, 361.Harvey, H. IT., 363.143390 INDEX OF AUTHORS’ NAMES.Hashimoto, Y., 375.Haslam, J., 338, 352.Hass, H. B., 201.Hassel, O., 202.Hassid, W. Z., 287, 288,289, 291, 298, 326, 328.Hastings, S. H., 366.Haszeldine, R. N., 14, 114,Hatch, L. F., 140.Hatch, M. J., 233.Hathway, D. E., 224.Hattori, K., 369.Haugaard, E. S., 311.Haul, R. A. W., 75.Hauptschein, M., 187.Hause, N. L., 132, 133, 236.Hauser, C. R., 133, 172, 175.Hauserman, I;. R., 250.Hausmann, W., 269.Hawdon, A. R., 134.Hawes, B. W. V., 126.Hawes, R. C., 363.Hawkins, B., 329.Hawkins, E. G. E., 145.Hawkins, J. A., 12.Hawley, D. W., 366.Haworth, E., 178.Haworth, W. N., 289.Hawthorne, F., 162.Haxo, F. T., 331.Hayashi, K., 329.Haybittle, J.L., 64.Haycock, E. W., 79.Hayes, J. C., 54.Hayes, T. J., 341.Haynie, W. H., 11, 15.Hayter, R. G., 100.Hazel, J . F., 116.Head, A. J., 132.Head, F. S., 150.Heal, H. G., 67, 376.Heaps, H. S., 17.Heath, D. F., 20.Heath-Brown, B., 250.Hecht, F., 375.Heck, R., 136.Heckmann, I., 111.Hedges, J. M., 71.Hedges, R. M., 127.Hedrick, L. R., 294.Hedvall, J. A., 70, 75.Heer, J., 226.Heesch, A., 215.Heggen, G. E., 367.Hegsted, D. M., 92.Hehre, E. J., 281.Heilbron, (Sir) I., 176, 178,Heilbronner, E., 175, 194.Hein, F., 106, 111.Heinemann, S. D., 173.Heinke, J., 109.Heitmiller, R. F., 238.Hele, M. P., 304.Hele, P., 304.I-Telferich, R., 158, 262, 266.128, 187.212, 334.Helfrich, G. F., 121.Helger, R., 368.Heller, H.A., 368.Heller, &I., 226.Hellermann, L., 149.Hellmann, H., 175.Hellstrom, N., 207.Helper, L. G., 101.Hems, B. A., 168, 238.Henbest, H. B., 178, 224,Henderson, A. W., 163, 199.Hendrickson, A. R., 128.Hendriks, S. B., 17.Hendus, H., 93.Henecka, H., 243.Heneghan, L. F., 121.Henery-Logan, K. R., 237.Hening, G., 67.Henkel, E., 158.Henkens, C. H., 239.Henne, A. L., 128, 175,Hennig, I., 175.Henry, J. A., 211.Henry, J. P., 163.Henry, R. A., 238.Hensel, H., 239.Hepburn, J. R. I., 74.Hepler, L. G., 30, 100.Heppolette, R. J., 129.Hepworth, M. A., 120.Herber, R. H., 49.Herbert, J., 39.Herbert, M. W., 374.Herbst, R. M., 239.Heritage, S. G., 238.Herling, F., 218.Herman, D. F., 103.Herman, R.C., 17.Hermon, S. E., 349, 361.Heros, M., 355.Herout, V., 207, 208.Herr, E. C., 32.Herr, M. E., 235.Herran, J., 229.Herrington, E. F. G., 370.Hersh, H. N., 31, 92.Hershberg, E. B., 169, 170,Hershberger, W. D., 10.Hershenson, H. M., 91, 365.Herz, J. E., 226.Herz, W., 234, 236.Herzberg, G., 9, 11, 17, 23.Herzberg, L., 9.Herzeberg, G., 22, 23.Herzfeld, L., 237.Herzog, H. L., 169, 170,Heslop, W. R., 14.Hestrin, S., 287, 297.Hetherington, G., 11 1.Heukelekian, H., 361.Heusler, K., 224.Heusser, H., 169, 211, 212,225, 230.187.229.188.232.Heutz, R. R., 47.Hewett, C. L., 190.Hewitt, F., 95.Hey, D. H., 332.Heyes, J. K., 130.Heyl, F. W., 235.Heymann, D., 49.Heyndricks, A., 361.Heyns, W. K., 352.Heyns, K., 264.Heyrovsky, J., 360.Heywood, A., 371.Hibbert, D., 286.Hickinbottom, W.J., 152.Hicks, H. G., 373.Hieber, W., 116, 117, 118.Hieger, I., 190.Hift, H., 304.Higginbotham, R. S., 288.Higgins, H. G., 37, 367.Higginson, W. C. E., 50, 51,Higgs, P. W., 14.Hilal, 0. M., 100.Hildahl, G. T., 192.Hildebrand, J. H., 88, 126.Hildenbrand, D. L., 105.Hilditch, T. P., 147.Hill, D. G., 133.Hill, D. R., 148.Hill, D. R. J., 57.Hill, T. G., 326.Hillebert, A., 113.Hillebrand, W. F., 338.Hillenbrand, E., 91.Hiller, A., 261.Hillmann, G., 276.Hillmann-Elies, A., 276.Hilpert, H. M., 298.Hilton, H. W., 259.Hilz, H., 304.Hinch, R. J., 369.Hindman, J. C., 90, 116.Hinds, L., 102.Hine, J., 131, 135.Hine, J. S., 137.Hinkel, R.D., 357.Hinman, J. W., 241.Hinshelwood, (Sir) C., 37,Hinsvark, 0. N., 368.Hipple, J. A., 24.Hirata, Y., 245.Hirozawa, S. T., 362.Hirs, C. H. W., 279.Hirschfelder, J. O., 81.Hirschmann, R., 230.Hirst, E. L., 289, 293, 323,325, 326, 329.Hiskey, C. F., 342, 366.Hitchen, A., 361.Hitchings, T. R., 128.Hoare, D. E., 47.Hobson, P. N., 288, 294,Hobstetter, J. N., 71.Hochanadel, C. J., 64.52, 105.39, 359.299, 300INDEX OF AUTHORS’ NAMES. 391Hochstein, F. A., 201, 261.Hockenhull, D. J. D., 253,Hockersmith, J. L., 55.Hodge, J. E., 262, 263.Hodge, N., 105.Hodges, R., 212.Hok, B., 366.Hoekstra, H. R., 95, 96,Hoschele, G., 254.Hofer, L. J. E., 116.Hoffman, P., 177.Hoffmann, I., 350.Hoffmann, J., 374.Hoffmann, J.I., 338.Hofmann, K., 166, 237.Hofmann, U., 93.Hogan, A. J., 65.Hogarth, J. W., 121.Hoijtink, G. J., 30.Holasek, A., 353.Holder, J., 92.Holdsworth, E. S., 375.Holker, J. S. E., 212, 213.Holland, D. O., 277.Holleman, A. F., 129.Hollenberg, J. L., 15.Holley, C. E., 89.Holley, C. E., jun., 30.Holley, T. F., 210.Holliday, A. K., 95.Hollingsworth, C. A., 168.Holloway, F., 151.Holmes, E. G., 315.Holmes, J. L., 236.Holms, W. H., 263.Holness, H., 343.Holroyd, E. W., jun., 137.Holt, P. F., 200.Holt, R. J. W., 241.Holterrnann, H., 219.Holysz, R. P., 171, 264.Homer, R. F., 257.Honeyman, J., 262, 263,266, 332,Honig, A., 12.Honma, N., 284.Honnen, L. R., 272.Hood, G. C., 74,Hoover, S. R., 272.Hopkins, R.H., 267, 288,291, 292, 294.Hoppe, W., 279, 371.Hopton, J. W., 359.Horak, O., 352.Hormats, E. I., 28.Horn, D. H. S., 182.Hornbaker, E. D., 241.Hornberger, C. S., 238.Hornberger, P., 95.Horner, L., 146.Hornhardt, H., 197.Hornig, D. F., 16.Horton, A. D., 366.Horton, W. S., 376.Horvitz, L., 97.374.376.Horwitz, J. P., 369.Hoste, J., 346, 365.Hotelling, E. B., 203.Hotz, M. C. B., 99.Houff, W. H., 359.Hougen, F. W., 173, 181,182.IIough, L., 169, 260, 261,266, 267, 293.Houlihan, J. E., 305.House, L. R., 254.Houston, B., 152.Howard, A. M., 368.Howard, G. L4., 215.Howard, R. O., 59.Howell, H. G., 22.Howlett, K. E., 38.Hoyle, B. E., 355.Hrdzi., M., 161.Hsu, S. K., 143.Huang, R. L., 231.Huang, W.-Y., 218, 226.Hubata, R., 275.Hubbard, D.M., 361.Hubbard, W. N., 32, 233.Huber, E. J., 30, 89.Huber, G., 258.Huber, W., 69, 254, 280.Hucker, H. B., 175.Huddart, J., 34.Hudgens, C. R., 370.Hudis, J., 48.Huditz, F., 341.Hudson, C. S., 260.Hudson, F. P., 42.Hudson, R. L., 12.Hubener, H. J., 224.Huebner, C. F., 241, 249.Hunig, S., 199.Huennekens, F. M., 318.Huggins, M. L., 33, 86.Hughes, A. C., 243.Hughes, B. P., 200.Hughes, E. D., 125, 127,125, 130, 132, 133, 134,136, 138, 139, 140, 141,143.Hu, J.-H., 32.Hughes, G., 150.Hughes, H., 57.Hughes, R. H., 10, 11, 369.Hugus, 2. Z., 100, 101, 113.Huh, G., 233.Huizenga, J . R., 113.Hulme, A. C., 257, 372.Hulse, G. E., 51, 144.Hume, D. N., 91, 93, 361,Humm, H.J., 327.Hummel, R. W., 64.Humphrey, G. L., 30, 89.Humphries, P., 17.Hund, F., 112, 113.Hunt, J . M., 369.Hunt, J . P., 57.Hunt, R. H., 175.Hunt, W. G., 352.377.Hunter, G. D., 231,309, 374.Hunter, G. J., 363.Hunter, J . G., 367.Hunter, I.., 189, 190.Hunter, R. F., 178.Huntsman, W. D., 201.Hurd, C. D., 236, 264.Hurd, C. H., 189.Hurt5 J., 359.Hurley, F. R., 111.Hurwitz, J. K., 368.Hussey, A. S., 154, 204.Husted, D. R., 187.Huston, B., 294.Huston, J. L., 49, 375.Hutchens, T. T., 310.Hutchings, B. L., 265.Hyde, E. K., 96.Hyde, G. E., 16.Hylander, D. P., 277.Hyman, €3. H., 113, 351.Ibarz AznArez, J., 349.Ichimura, H., 87.Ichishima, I., 12.Icken, J. M., 363.Idler, D. R., 232.Ievinsh, A.F., 353.Ihrig, J . L., 59.Ikawa, M., 182, 185.Ikenaka, T., 294.Ikenberry, L., 366.Illingworth, B., 290.Illuminati, G., 127.Illuminati, M. P., 127.Ilse, D., 173, 181.Imanaga? Y., 260.Infante, A., 269.Ingersoll, A. W.. 158.Inghram, M. G., 31, 101.Ingles, T. A., 47, 148.Ingold, C. K., 20, 54, 125,127, 130, 132, 133, 134,136, 139, 140, 143.Ingold, K. U., 34, 40.Ingraham, L. L., 135, 136.Ingram, G., 357.Ingram, V. M., 272, 275.Inhoffen, H. H., 181, 228.Inokuchi, K., 325.Inskeep, R. G., 13.Ipatieff, V. N., 201.Irion, W., 236.Irish, R., 354.Irvine, D. S., 211.Irving, H., 90, 340, 366.Isaeff, E., 310.Isbell, H. S . , 261.Iseda, H., 215.Iseda, S., 215.Isherwood, F. A., 279, 289.Ishihara, Y., 333.Ishikawa, H., 206.Islam, A.M., 204.Isler, O., 181.Issa, I. M., 362.Ito, K., 33392 INDEX OF AUTHORS’ NAMES.Tto, S., 331.Ivash, E. V., 10.Ivin, K. J., 62.Ivinson, M. G., 188.Ivy, H. B., 314.Iwasaki, I., 377.Jack, R. H., 165.Jackson, C., 348.Jackson, M. L., 339.Jacob, R., 139.Jacob, T. A., 170, 225.Jacobs, P. W. M., 73, 76, 79Jacobs, R. M., 367.Jacobs, T. L., 131.Jacobs, W. A., 157, 253.Jacobsen, G., 242.Jacobson, M. G., 376.Jacombs, F. E., 195.Jacquignon, P., 190.Jaenicke, L., 256, 375.Jaffe, H. H., 13, 55.Jahn, H. A., 9.James, D. H., 372.James, S., 271.James, V. H. T., 219.Jamieson, G. A., 244.Jander, G., 99.Jander, J., 187.Jangg, G., 353.Janischeva, 2. S., 76.Janot, M. M., 248.Jansen, A.B. A., 168, 238.Jansen, E. F., 271.Jantsch, G., 366.Jarrett, S. G., 143.Jarry, R. L., 32.Javan, A., 12.Jean, M., 363, 367.Jeger, O., 160, 169, 210, 211,212, 214, 253.Jelinek, B., 292.Jelinek, V. C., 270.Jellinek, H. H. G., 61, 62.Jenkins, A. D., 30, 60.Jenkins, P. A., 277.Jenness, R., 340.Jenny, E. F., 168, 186.Jensen, E., 371.Jensen, I<. A., 123.Jensen. V. G., 377.Jepson, J. B., 279, 374.Jerie, H., 358.Jermyn, M. A., 375.Jevnik, M. A., 169.Jewsbury, A., 343.J ezowska-Trzebiatowska,B., 116,Jiri, R., 115.Jocelyn, P. C., 174, 183.Johr, K. F., 112.Johannesen, R. B., 131.Johanson, R., 254.Johns, A. T., 318.Johns, W. F., 219.Johnson, C. L., 352.Johnson, C. M., 9, 10.Johnson, D. A., 237, 238.Johnson, D.H., 148.Johnson, D. R., 232.Johnson, K. C., 263.Johnson, K. D. B., 112.Johnson, N. G., 333.Johnson, N. M., 147.Johnson, 0. H., 104, 339.Johnson, R. A., 364.Johnson, R. D., 12.Johnson, ‘EV. S., 175, 216Johnston, H. L., 31, 32, 35Johnston, E-I. S., 37, 39, 40.Johnston, J. D., 214.Johnston, R., 328.Johnston, W. H., 46.Jolly, W. L., 30, 90.Jonassen, H. B., 119, 121.Jonckers, M. D. E., 340.Jones, A. R., 374.Jones, B., 131.Jones, D. M., 285.Jones, E. M., 218.Jones, E. R. H., 176, 177,211, 212, 213, 215, 225.Jones, F. T., 369, 370.Jones, G. B., 361, 372.Jones, H. W., 136.Jones, J. K. N., 169, 253,260, 261, 266, 267, 293,325, 326, 327, 329, 367.Jones, L. H., 13.Jones, M. E., 303, 304.Jones, M. H., 41, 42, 125.Jones, P., 55, 142.Jones, R.N., 17, 218, 232.Jones, R. T., 352.Jones, W. E., 178.Jones, W. G. M., 327.Jones, W. H., 357.Jones, W. M., 107.Jones, W. O., 92.Jordan, D. O., 119, 365.Jordan, J., 361, 362.Jordan, J . W., 340.Jorgensen, H. E., 229.Jorgenson, E. C., 368.Joseph, J . P., 251.Joseph, N., 97, 169.Joshi, G. V., 374.Josien, M. L., 14.Joslyn, M. A., 291.Jouanneteau, J ., 229.Journeay, G. E., 140.Jowett, M., 312, 317.Jucker, E., 166, 245.Judah, J. D., 308.Judge, W. A., 133.Julia, M., 215.Julian, P. L., 242.Junk, R., 244.Jura, G., 88.Jutisz, &I., 273, 274.Jutz, C., 279.Juvala, A., 131.220, 227.89.Juvet, R. S., 342.Juza, R., 91.Kabadi, M. B., 349.Kachan, A. A., 51.Kagan, F.E., 350.Kagarise, R. E., 12.Kahita, Y., 347.Kainz, G., 346, 358.Kaiser, E., 275.Kaizerman, S., 233.Kall, H. L., 349.Kalugai, I., 92.Kan, B., 64.Kandel, I., 276.Kane, W. R., 23.Kanner, B., 239.Kantor, S. W., 102, 133.Kantro, D. I>., 46.Kantrowitz, A., 72.Kanzelmeyer, J. H., 366.Kapel, M., 339, 352.Kaplan, N. O., 303.Kaplan, R. B., 152.Kappeler, H., 205.Kappelmann, I?. A., 100.Kapur, S. L., 58.Karabincs, J. V., 266.Karawia, M. S., 356.Karel, M., 64.Karle, I. L., 123.Karmas, G., 141, 176.Karnemaat, J . N., 223.Karrer, P., 178, 179, 180,206, 259, 274, 280, 334.Kassel, L. S., 35.Katayama, T., 330.Katchalsky, A., 264.Kato, T., 355.Katsoyannis, P. G., 268.Katsura, S., 82.Katz, C., 32, 233.Katz, J., 298.Katz, J.J., 95, 113, 351,Katz, S., 336.Katzbeck, J., 296.Katzbeck, W. J., 300.Katzenellenbogen, E., 232.Katzin, L. I., 30, 370.Kauffman, W. B., 377.Kaufman, F., 37.Kaufman, S., 313.Kaufmann, S., 229.Kautsky, H., 101, 103.Kay, €3. D., 320.Kay, K., 370.Kay, L., 103.Kazanskii, B. A,, 201.Kearney, E. B., 306.Keck, P. H., 94.Keefer, R. M., 49, 126, 188.Keen, R. T., 377.Kehr, C. L., 149.Keil, W., 319, 321.Keir, D. S., 17.Keller, F., 249, 252.376INDEX OF AUTHORS’ NAMES. 393Keller, W., 208.Kellogg, K. B., 113.Kellom, D. B., 174, 199.Kelly, R. B., 251.Kelly, S., 335.Kelso, J. R., 37.Kemp, A. D., 220.Kemula, W., 361, 371, 374.Kendall, D. N., 368.Kennard, O., 234.Kennedy, E. P., 301.Kenner, G.W., 245, 274.Kenner, J., 171, 323.Kenny, F., 355.Kentie, A, 30.Kent- Jones, D. W., 338.Kenyon, J., 143, 151, 153,Kenyon, 0. A., 364.Kepner, R. E., 130.Keps, J. S., 262.Kern, S. F., 238, 370.Kerr, R. W., 288, 289, 292,Kessler, H. K., 15.Ketcham, R., 242.KCthelyi, J., 351.Ketlcy, A. D., 128.Khan, M. A., 44.Khan, M. H., 186.Kharasch, M. S., 146.Kha.wam, A., 158.Khodulina, P. V., 344.Kholopova, L. S., 291.Khorana, H. G., 274.Khym, J. X., 245, 256, 372.Kidd, J. M., 187.Kierstead, R. W., 201.Kikuchi, R., 83.Kilpatrick, M., 345.Kimoto, W. I., 242.King, E. L., 51, 54.King, F. E., 210, 214, 240.King, G. W., 20.King, J. A., 278.King, T. J., 210.King, W. C., 12.King, W. H., 140.Kingsley, G. R., 368.Kingsley, R.B., 157.Kinnory, D., 320.Kipping, F. B., 214.Kirby, H. W., 375.Kirchhof, W., 193, 241.Kirk, P. F., 233.Kirk, P. L., 350, 362, 363.Kirk, R. E., 5.0.Kirkpatrick, A. F., 356.Kirkwood, J. G., 72, 80, 81,Kirkwood, S., 245.Kirrmann, A., 139, 140.Kirschenlohr, W., 264,Kirshenbaum, A. D., 187.Kirson, B., 53.Kirsten, W., 356, 357.Kisieleski, TV. E., 375.162.296, 300.82, 84, 153.Kisliuk, P., 19.Kiss, J., 185.Kissman, H. M., 145, 233.Kistiakowsky, C. B., 25.Kistiakowsky, G. B., 39, 40Kitahara, K., 297.Kivalo, P., 120, 360.Kjaer, A., 375.Klaiui, H., 208.Klamberg, H., 34.3.Klailke, E., 173.Klein, E., 30.Klein, J. A., 12.Klein, N. J., 368.Klein, S. F., 365.Kleinberg, J . , 1 16.Kleinspehn, G.G., 234.Klerner, A., 258.Kline, G. B., 157, 201.Kling, h., 177.Klingenberg, J. J . , 349.Klingler, W., 110.Klingman, D. W., 366.Klingsberg, A., 223, 252.Kloetzel, M. C., 188, 237.Klohs, M. W., 349, 252.Klosty, M., 332.Klotz, J. M., 340.Klug, E-I. P., 370.Kluiber, R. W., 197.Klyne, W., 209, 216, 249.Knapp, D. W,, 288, 292Knight, C. A., 273.Knight, H. B., 147, 361.Knight, J., 95.Knight, J. D., 137.Knight, S. A., 211.Knoop, F., 319.Knotz, F., 345.Knowles, G., 362.Knowles, W. S., 219.Knox, W. E., 301.Kobayashi, T., 299.Koch, C. W., 30, 100.Koch, W., 264.Koefoed, J., 87.Koegel, R. J., 157.Kogler, H., 20.5.Koehmstedt, P. L., 364.Koelsch, C. F., 242.Koepfii, J. B., 182, 185.Koppe, H., 306.Korner, K.F., 350.Koerner, W. E., 28.Koster, M., 99.Koszegi, D., 359.Koether, B., 237.Kofier, A., 369.Kohanyi, G., 282.Kohler, M., 347.Kohn, A., 376.Kohn, M., 344, 354.KohtBs, L., 284.Kolb, D. K., 264.Kolbezen, M 3 . . 104.Kolditz, L., 109.296.Kolthoff, I. M., 116, 119,145, 352, 361, 362, 365.Komarmy, J. M., 363.Konovalov, A., 357.Kontowicz, A. D., 174.Koo, J., 194.Kooyman, E. C., 42,43,148Koren, H., 364.Korkes, S., 302.Korn, A. H., 272.Kornberg, A., 301, 303, 305.Kornblum, N., 134.K6r6s1 E., 353.Korte, F., 246.Korvezee, A. E., 32.Koshi, J. I<., 135.Koshland, D. E., 282.Kosolapofi, G. M., 355.Kostic, R. B., 218.Iiotani, M., 19.Kotlan, J., 149.Kovi~cs, J., 276.KovBcs, K., 276.Kovi~cs, O., 165, 166.Kovaliv, B., 65.Kraft, R., 178.Krainiclr, H.G., 357.Kramer, H. P., 362.Kramer, Th. J. E., 30.Kramer, W., 308.Krasnovskii, A. A., 331.Krause, H. H., 339.Kraychy, S., 221.Krc, J., 369.Krebs, H., 108.Krebs, H. A., 313, 314.Kreger, D. R., 323.Kreiser, W., 152.Krekels, A., 273.Kremers, H. E., 364.Kresse, G., 154.Kreuchunas, A., 173, 356.Kreutzberger, -4., 241.Kriege, 0. H., 351.Krieger, K. A., 150.Krishnamurty, K.V. S ,349.Kristensen, K., 324.Kritsky, G. A., 297.Kroger, C., 31.Kropcr, H., 172.Krook, S., 30.Kruber, O., 188.Kriierke, U., 98.Kruger, B., 228.Krum, W., 239.Krumholz, P., 119.Kruschwitz, H. W., 112.Kruse, F. H., 358.Kruse, J. M., 363, 364.Kubitshek, M. J., 255.Kuchinke, E., 177.Kuck, J.A., 345.Ruehl, F. A., 270.Xiing, W., 203.Kuenne, D. J., 261.Kuhn, R., 163,173, 179,180,181,238,263,264,284,322394 IXDEX OF AUTHORS' NAMES.Kuhn, W., 153, 205.Kuivila, H. G., 128.Kulberg, L. M., 345.Kulka, M., 242.Kumada, M., 12.Kumov, V. I., 348.Kung, J. T., 294.Kunkel, H. G., 268.Kunzler, J. E., 110, 350.Kupchan, S. M., 253.Kurasawa, H., 284.Kurata, M., 85.Kuratani, K., 12.Kurihara, O., 172.Kurtz, R. B., 355.'Kurtz, T., 341.Kurushima, M., 297.Kusche, H., 373.Kushnever, M., 77.Kutlu, O., 242.Kuvaeba, E. B., 297.Kuyper, A. C., 290.Kuzina, L. S., 49.Kuznetsov, V. I., 345.Kyburz, E., 211.Kylin, H., 325, 326, 329.Labaton, V. Y., 257.Lacher, J. R., 187.Lacourt, A., 356, 374.Lad, R. A., 95, 113.Ladacki, M., 26, 39.Lademann, R., 158.Ladenbauer, 1.-M., 375.Lady, J .H., 365.Lafon, M., 330.La Forge, F. B., 158.Lagrance, G., 171.Lagrev, R., 294.Laird, R. K., 22.Laitinen, H. A., 94, 120,Lalos, G. T., 23.Lamb, A. B., 119.Lamb, F. W., 104.Lamb, J., 34.Lambert, J. L., 355, 377.La Manna, A., 162.Lamond, J. J., 350.Lamport, J. E., 12.Lancaster, J. E., 13.Landauer, P. D., 240.Landauer, S. R. 171.Landmann, W. A., 270,275.Landquist, J . T., 146.Lane, M. R., 27.Lane, R. L., 294.Lang, K., 318, 320.Langdon, R. G., 232.Langer, A. W., jun., 264.Langer, S. H., 138.Langford, K. E., 341.Lappert, M. F., 98.Lardon, A., 216.Lardy, H. A., 302, 316, 317.Larner, J., 290, 297.Larsen, E. M., 104, 343.360.Larsen, H., 318.Larson, H.O., 228.Larson, N., 294.Laskowski, D. E., 369.Latimer, W. M., 30, 90, 101.Lauer, W. M., 126.Laurila, U., 273.Lautenschlager, H., 279.Lautner, H., 321.Lautout, M., 37.Lavie, D., 253.Lavine, L. R., 94.Lawes, J . B., 308.Lawler, H. C., 268.Lawley, H. G., 323.Lawrance, W. A., 361.Lawrence, A. M., 351.Lawrence, K. R., 343.Lawson, A., 278.Lawson, M. O., 340.Lawson, N. D., 364.Lawton, E. J., 66.Layne, G. S., 44.LaZerte, J. D., 187.Lea, C. H., 264, 273.Lea, D. E., 67.Leadhill, W. K., 190.Leahy, G. D., 129.Leanza, W. J., 278.Lear, J . B., 365.Leaver, F. W., 318, 319.Lebas, J . M., 14.Leber, D., 244.Leboeuf, M. R., 375.Lecomte, J., 206.Leddy, J., 104.Lederer, E., 174, 179, 183,Lederer, M., 170, 373, 374,Leditschke, H., 175, 236.Lee, D.E., 133, 135.Lee, M., 157.Leedham, K., 187.Lees, R., 67.Leete, E., 241, 245.Lefever, R. A., 102.Le Fkvre, R. J. W., 15.Leffler, N., 374.Lefort, M., 69.Legay, F., 263.Ldger, E. G., 34.Le Gette, J., 272.Legg, J . W., 330.Le Gloahec, V. C. E., 331.Le Hir, A., 249.Lehmann, H. A., 109.Lehninger, A. L., 301, 305,Leichsenring, G., 146, 170.Leigh, H. M., 222, 223.Leighton, F., 37.Leiter, H., 63.Leloir, L. F., 301, 306.Lemaire, H., 227.Lemberg, R., 330.Lemieux, R. U., 268, 266.184.375.308.Lemin, A. J., 210, 212, 215.Lemmon, W. R., 377.Lemon, J. McW., 327.Lendrum, F. C., 157, 378.Lenhard, R., 226, 232.Lenk, C. T., 171, 230.Lenpard-Jones, J .E., 80.Lennox, D. H., 370.Lenormant, H., 15.Lens, J., 271.Leo, A., 151.Leonard, N. J., 192, 194,240, 245,LeRosen, A. L., 179, 343.Leroux, J., 370.Le Roy, D. J., 41, 45, 46.Lesslie, M. S., 155.Letaw, H., 15.Letort, M., 47.Leucutia, T., 64.Leumann, E., 180.Leussing, D. L., 116, 119,Levi, A. A., 238.Levin, R. H., 223.Levina, R. Ya., 201.Levine, M., 187.Levine, R., 187.Levintow, L., 157.Levitt, L. S., 53.Levitz, M., 135, 175.Levring, T., 333.Levy, A. L., 279, 375.Levy, J . L., 129.Levy, M., 276.LCvy, R., 356, 357.Lewin, S., 362, 365.Lewinson, V. A., 82.Lewis, B. A., 254.Lewis, E. S., 57, 135, 138.Lewis, G. E., 145, 199, 200.Lewis, G. N., 74.Lewis, J., 105, 106.Lewis, J . A., 360, 368.Lewis, J.R., 167, 229, 365.Lewis, R. W., 368.Li, C. H., 270, 272.Liang, C. Y., 12.Liao, H. P., 204.Libby, W. F., 48.Libowitz, G. G., 94.Lichtenwalter, M., 123.Lichtin, N. N., 144.Li Chu, T., 98.Liddel, U., 17.Liddell, H. F., 363.Lieb, H., 358.Lieber, E., 238, 369.Liebhafsky, H . A., 363, 370.Liebmann, H., 374.Lieck, K., 113.Lifson, N., 317.Lilker, J., 39.Lincke, H., 321.Lincoln, G. J., 312.Lindberg, B., 266, 267, 288,365.323INDEX OF AUTHORS’ NAMES. 395Linde, H. W., 377.Lindegren, C. R., 135, 136.Linden, H., 167.Lindenmann, A., 166, 245.Lindenmeyer, P. H., 12.Lindholm, E., 63.Lindsey, ,4. J., 188, 207,Linevsky, M. J., 98.Linhard, M., 111, 119.Link, K. P., 265.Linko, E., 365.Linnett, J. W., 9, 14, 20, 27.Linschitz, H., 47, 144.Linstead, R.P., 173, 174,Lions, F., 119.Lipkin, D., 63.Lipman, F., 302.Lipmann, F., 245, 303, 304,Lippincott, E. R., 13, 14,Lipps, G., 363.Lipscomb, TV. N., 94, 98,Lisle, E. B., 148.Lissitzky, S., 276.Lister, M. W., 112.Littell, R., 169, 226.Little, H. N., 230.Little, J. E., 237.Little, K., 66.Littlefield, J. W., 313.Liu, L. H., 203.Livingstone, J. K., 364.Livshits, R. S., 247.Liwschitz, Y., 278.Llacer, A. J., 355.Llewellyn, D. R., 50, 54,Lloyd, D., 204.Locker, R. H., 243.Loebl, H., 145.Loffler, J. E., 374.Lofgren, N., 244.Lofman, C., 92.Lijsel, M., 108.Low, I., 322.Lohaus, G., 170.Lohmann, K. H., 134.Loh Ming, W.-C., 340.Lohr, L. J., 358.Londergan, T. E., 236.Long, C., 184.Long, D.A., 13, 18.Long, F. A., 60, 143.Long, G., 55.Long, L. H., 33, 89.Long, R., 147.Longstaff, J. V. L., 352.Longuet-Higgins, H. C., 84,Longworth, L. G., 375.Loomis, W. F., 312.Looney, F. S., 167.Lopez Santos, I., 376.208.182, 186, 201.306, 318.30.370.112,120.87, 191.Lorber, V., 316, 317.Loriers, J., 372.Loscalzo, A4. G., 346.Losing, F. P., 34, 40.Loudon, J. D., 196.Loughran, E. D., 92.Lovell, B. J., 224, 225.Lowry, T. M., 142.Lowden, G. F., 362.Loweus, F. A., 161.Lowy, S. L., 348.Loxley, R., 286.Lucas, H . J., 153.Lucena-Conde, F., 344, 350.Lucius, G., 205.Luckey, G. W., 44.Luder, W. F., 99.Ludewig, W. H., 361.Liining, B., 244.Liittke, W., 239.Luft, N. W., 35.Lugg, J .W. H., 330.Lui, L. H., 144.Luke, C. L., 339, 364, 366.Lukens, F. D. W., 310,LukeS, R., 173.Lukes, R. M., 219.Lukina, M. Yu., 201.Lumb, P. B., 181.Lumpkin, H. E., 140.Lund, L. H., 81.Lundell, G. E. F., 338.Lundin, B., 30.Lunt, E., 253.Lunt, J. C., 173.Lutwak, H. K., 363.Lutwak, L., 181.Lutwick, G. D., 349.Lutz, A. W., 207.Luver, C., 65.Lydersen, D., 341, 342, 362.Lynch, B. M., 145.Lynen, F., 245, 302, 303,304, 306.Lyon, I., 310.Lyons, H., 11.Lythgoe, B., 177.Lyttle, D. A., 222.Lyuboshits, I., I., 121.Ma, T. S., 338, 355, 358.Maas, W. K., 304.Mabane, A. D., 141.Mabis, A. J., 370.McAllister, R. A., 366.McAlpine, R. K., 344.McBee, E. T., 187.Macbeth, A. K., 202, 204,McBeth, R., 104.MacBryde, W.A. E., 339,McRurney, E. H., 361.McCaleb, K. E., 221.Maccoll, A., 38.McConaghie, V. M., 11.313.205.366.MacCormack, K. E., 87.McCoy, R. E., 37, 94.McCready, R. M., 289.McCrone, W. C., 369.McCulloh, K. E . , 10.McCullough, J . P., 32, 233.McCurdy, W. H., 362, 365.McCutcheon, T. P., 91, 100.Macdonald, A., 358.MacDonald, D. L., 266.Macdonald, J . C. F., 14.Macdonald, J. Y., 72, 73, 76.MacDonald, S. F., 234.McDowell, C. A., 13, 25.McDuffie, B., 367.McElvain, S. M., 139.McEvoy, F. J., 251.McEwen, W. E., 248.McGeown, M. G., 260.McGhie, J. F., 211.McGookin, A., 215.Machado, A. L., 303.Macheboeuf, M., 375.McIntire, F. C., 367.McIntosh, A. V., 223.McIntyre, G. H., 90.McIver, R. D., 360.Mack, C. H., 182.MacKay, E .M., 317.McKay, F. C., 280.McKean, D. C., 16.McKean, L. C., 214.Mackela, A. A., 362.McKenna, J., 252, 328.McKenna, J. F., 233.McKenzie, A., 160.Mackenzie, H. A. E., 50.McKinley, J. D., 358.Mackinnon, D. J., 52, 144.McLamore, W. PI., 238.MacLean, A. F., 176.Maclean, D., 224.McLean, P., 315.McLellan, A. G., 81.McMahon, R. E., 137, 142.McMahon, W. J., 376.McMillan, F. H., 278.McMillan, W. G., 86.McMullan, W. H., 367.McNabb, W. M., 116.McNees, R. A., 116.MacNevin, W. M., 339, 351,360, 361, 372.MacNulty, B. J., 363.McOmie, J . F. W., 370, 374.Macpherson, M., 294.Macpherson, M. G., 322,MacPhillamy, H. B., 249,McPhillips, J . , 36 1.McSharry, J. J., 112.McSweeney, G. P., 257.IMcVey, W. H., 48, 113.Maddams, W.F., 366.Maddock, A. G., 102.Maddock, J. G., 374.329.332396 INDEX OF AUTHORS’ NAMES.Madley, D. G., 376.Madoff, M., 190.Madorsky, S. L., 61.Mafune, K., 281.Magat, M., 37, 67.Magee, J., 52.Magee, J. L., 67.Magerlein, B. J., 222, 223,Maggs, J., 78.Magnusson, L. B., 113.Magrath, D. I., 245.Maguire, M. F., 184.Mahadevan, A. P., 374.Mahler, H . A., 302.Mahler, H. R., 304, 305,Mahr, C., 345.Maier-Hiiser, H., 268.Majumdar, A. K., 348, 365.Majumdar, S. G., 252.Majury, T. G., 41.Makar, S. M., 188.Maki, G., 88.Makstmova, G. V., 49.Malatesta, L., 120.Malen, C., 343.Malesh, W., 252.Malissa, H., 345, 373.Malkin, T., 184, 185.Mallett, M. W., 376.Malpress, F. H., 255, 260,Malz, H., 109.Mamberto, R.I., 352.Mampel, K. L., 72.Mancera, O., 169, 170.Manchot, W., 117.Mandell, L., 169.Manes, M., 34.Mann, D., 31.Mann, D. E., 12, 98.Mann, K. M., 223.Mannelli, G., 354, 355.Manners, D. J., 290, 296.Mannheimer, W. A., 344.Manowitz, B., 64.Mansfield, G. H., 368.Mansfield, R. C., 171.Manske, R. H. F., 242, 247.Manson, W., 215.Manyik, R. M., 175.Mapper, D., 376.Mapstone, G. E., 148.Maraghini, M., 361.Marcus, R. J., 47, 48.Marey, A. F., 198.Margerum, D. W., 55, 337,Margrave, J . L., 21, 27. 31.Marinetti, G., 185.Marion, L., 241, 245, 240.Marke, D. J. B., 79.Marker, R. E., 218.Markle, G. E., 365.Marks, H. P., 315.Marks, J . L., 156.224.318.375.365.Markus, J., 75.Marple, T. L., 361.Marsen, H., 239.Marsh, J .K., 100.Marsh, M. M., 373.Marshall, H., 135.Marshall, H. G. B., 38.Marshall, I., 61.Marshall, R., 38.Marshall, S. M., 327.Martell, A. E., 91, 340, 343.Martin, A. E., 17, 364, 373.Martin, A. W., 346.Martin, E. L., 366.Martin, G., 364.Martin, H., 140.Martin, J . B., 186.Martin, J. L., 366.Martin, J . T., 58.Martin, R. B., 47.Martin, R. J. L., 134.Martin, R. L., 97.Martinez, H., 229.Martinez, J. B., 94.Martini, C. M., 165.Martinovich, K., 374.Martius, C., 318.Martlew, E. F., 265.Martynoff, M., 200.Maruo, B., 299.Marvin, G. G., 78.Marwitz, H., 236.Marzadro, M., 357.Marzluff, W. F., 187.Mason, G. W., 373.Mason, S . G., 87.Masoro, E. J., 309, 310.Masri, M. S., 310.Mast, C. B., 14.Mastagli, P., 171.Mastaglio, D., 236.Master, R.W. P., 374.Masterman, S., 143.Matell, M., 158.Mathes, W., 239.Matheson, H. R., 315.Matheson, M., 67.Mathieson, A. McL., 211.Mathot, V., 84, 86.Msthot-Sarolea, L., 83.Matossi, F., 18.Matsubara, Y., 333.Matsubayashi, H., 326.Matsumoto, T., 348.Matsnshima, Y., 260.Matsuura, S., 245.Matthews, L. W., 301, 313.Mattraw, H. C., 65.Maun, E. K., 82.Mautner, H. G., 335.Maxwell, J. A,, 361.Maxwell, L. C., 275.May, C., 12.May, S. C., 271.Mayer, A., 362.Mayer, J. E., 81, 81, 86, 87,159.Mayer, J. R., 192.Mayer, M. G., 82.Mayer, S. W., 342.Mayne, J. E. O., 116, 367.Maynert, E. W., 240.Mayo, F. K., 58.Mazur, A., 330.Meadow, M., 247.Meakins, G. D., 214.Mebane, A.D., 176.Mecke, R., 17.Meckelburg, A., 188.Medalia, A. I., 361.Medenwald, H., 242.Medes, G., 302, 309, 313.Medvedev, S. S., 62.Meehan, E. J., 146.Meek, E. G., 202.Meek, J. S., 132, 133.Meeker, R. F., 367.Meeuse, B. J. D., 323.Mehlig, J. P., 364.Mehrotra, R. C., 103, 341.Meier, D. J., 360.Meier, H. L., 160.Meigh, D., 134.Meigh, D. F., 143.Meiners, A. F., 187.Meinke, M., 317.Meinke, W. W., 376.Meinwald, J., 166, 192.Meisels, A., 193.Meisinger, M. A. P., 270.Meislich, E. K., 161, 272.Meister, A,, 157.Meister, A. G., 12.Neister, P. D., 222, 223.Meites, L., 360, 361.Mel, H. C., 30.Mela, H., 3G8.Melander, L., 126.Meldau, R., 75.Meller, A,, 266.Melles, J. L., 236.Mellon, E. F., 272.Mellon, 19.G., 363, 364, 363,Mellor, D. H., 90, 340.Melnick, L., 373.Meloche, V. W., 232.Melsted, S. W., 341.Melville, H. W., 41, 42, 47,59, 70, 148.Mendenhall, R. M., 270.Menzel, H., 107.Menzel, K. H., 228.Merritt, C., 365.Merritt, L. L., 340, 370.Merz, J . H., 151.Meschke, V. H., 373.Messerly, J. F., 32, 233.Messina, N., 261.Metcalf, W. S., 105.Metter, E., 111.Metzger, J., 237.Meunier, N., 359.Meunier, P., 229.373INDEX OF AUTHORS' NAMES. 397Meuwsen, A., 108.Meyer, A. D., 110.Meyer, J., 92, 316.Meyer, K., 232.Meyer, K. H., 288, 289, 291295, 298, 299.Meyer, S., 208.Meyer-Brunot, H.-G., 240.Meyer-Simon, E., 92.Meystre, C., 226.Micheel, F., 258, 261, 375.Michel, G., 342.Michel, R., 276.Micheli, R. A., 169.Michels, A., 88.Michelson, A.M., 245.Michl, H., 268.MiCoviC, V. M., 168.Middleton, G., 339.Midorikawa, H., 236.Miescher, K., 221, 226.MihailoviC, M. Lj., 168.Mii, S., 305, 307.Mikhailova, E. S., 291.Miki, T., 206.Mikkelsen, L., 12.Mildner, P., 181.Miles, D., 195.Miles, G. L., 89.Milhaud, G., 290.Miller, C. C., 347, 348.Miller, F. A., 12.Miller, F. F., 373.Miller, G. A., 80.Miller, H. K., 280.Miller, H. W., 133.Miller, J., 129, 143, 148.&filler, N., 64, 66.Miller, S. I., 12.Miller, S. J., 133.Miller, S. L., 11, 19.Milligan, B., 204, 205.Millington, R. H., 301,Mills, E. C., 349, 361.Mills, G. A., 50.Mills, I. M., 10.Mills, J. A., 202, 203, 210,Milner, A. M., 50.Milsted, J., 74.Milton, H.T., 89.Minder, W., 64.Minegishi, J., 192.Miner, F. J., 372.Ming, W. C. L., 111.Miniger, R. F., 232.Minkoff, G. J., 361.Miquel, R., 65.Miramontes, L., 227.Mird Plans, P., 348.Miropol'skaya, M. A., 206.Mirza, R., 165, 245.Misiorny, A., 267.Mislow, K., 146.R'Iisra, A. L., 344.Mitcheii, A. G., 46.312.216.Mitchell, H. K., 237.Mitchell, J. W., 71, 78.Mitchell, M. B., 237.Mitchell, P. W. D., 263, 264Mitchell, R. L., 334.Miwa, T., 281, 329.Miyake, A., 12.Miyake, S., 329.Miyazawa, T., 12.Mizushima, S. I., 12.MladenoviC, S., 360.Mockler, R. C., 10.Modic, F. J., 127.Moller, K., 242.Moeller, T., 100, 104, 366.Moersch, G. W., 277.Moffett, R. 13, 209.Mogeneen, S., 364.Mohler, F. L., 25, 61.Mold, J.D., 189.Moldenhauer, O., 236.Monack, L. C., 129.Mondou, O., 205.Monfils, A., 12.Mongini, L., 70.Monk, P. R., 343.Montgomery, R., 254, 255Montroll, E., 81.Moon, K. -4., 74.Moore, A. C., 277.Moore, B. P., 245, 246.Moore, C. G., 145.Moore, M., 252.Moore, R. F., 148.Moore, S., 279, 372.Moore, T. E., 120.Moore, W. A., 362.Morehead, F. F., 64.Moreland, W. J., jun., 203.Morgan, D. M., 255.Morgan, J. W. W., 266.Morgan, W. H. D., 158.Mori, I., 375.Mori, M., 105.Mori, T., 322, 328.Morita, H., 60.Morita, H. H., 42.Moritani, I., 133.Morren, L., 362.Morris, -4. L., 57.Morrison, A. L., 178.Morrison, G. A., 288.Morrison, &I., 290.Morse, B. K., 135, 136.Morse, J. G., 202.Mortimer, C. T., 26, 28, 29.Mortimore, D.M., 368.LTorton, J. E., 355.Llorton, R. A., 178, 334.Morton, R. K., 286.Moser, C. M., 191.Iloser, J . H., 364.Vloser, P., 90.vlosettig, E., 218, 228.Vlosher, W. A., 149.floss, B. L., 322.288, 371.Moss, J. -4., 272.Moss, M. L., 339.Mosyagina, M. A., 121.Mott, N. F., 78.Moudy, L., 366.Mousseron-Canet, M., 203.Moyls, A. W., 340,Mudd, S. G., 182, 185.Muller, A., 255.Miiller, G., 107.Mueller, G. C., 148.Mueller, J. M., 269.Miiller, R. H., 79.Miinster, A., 85.Mukai, T., 192.Mukharji, P. C., 202.Mukherjee, S., 253.Mukherji, S. M., 207.Mulcahy, M. F. R., 57, 148.Mulder, D., 30.Muller, N., 10.Mulliken, R. S., 33, 126.Mumm, O., 197.Mundiel, R., 102.Mundy, B. W., 300.Mufioz, J. M., 301.Munro, D.J., 53.Murai, K., 261.Murata, H., 12.Murati, I., 119.Murphy, G. W., 74, 80.Murray, F. E., 87.Murray, H. C., 222, 223.Musha, S., 364.Musil, A., 349, 355, 366.Muthana, M. S., 370.Myers, D. R., 244.Myers, H., 48.flyers, R. J., 12.Myrback, I<., 287, 288, 291,294, 295.Nabarro, F. R. N., 71.Yace, H. R., 218, 230.qachmansohn, D., 303.IrTachod, F. C., 165.qachtman, E. S., 373.VAdor, K., 164, 165.Vaeser, C. R., 121.qaffa, P., 208.qagel, R., 358.gagle, J. R., 202.\Tagy, H., 278.qair, C. K. N., 381.?air, P. M., 55.Jakagawa, I., 12.qakanishi, I<., 232.Jalbandyan, A. B., 46.JAnAsi, P., 362.Jarasimhan, S., 246.larasimhachari, hT., 243.iarita, K., 278.Sasielski, J., 84.Tasr, H., 294, 300.Jast, R., 117, 118.Jathan, A.H.. 222.laves, Y.-R., 206398 INDEX OF AUTHORS’ NAMES.Nawa, S., 245.Nayler, J. H. C., 277.Neale, A. J., 371.Nebe, E., 319.Neber, P. W., 233.Needham, D. M., 304.Neelakantam, K., 354.Nef, J. U., 261.Neidig, H. A., 152.Neill, IC. G., 210.Neiman, M. B., 49.Neish, W. J . P., 375.Nelson, E. R., 249.Nelson, J. A., 170, 193.Nelson, J. F., 312.Nelson, ‘K. L., 125.Nelson, N. A., 169.Nelson, R. D., 13.Nelson, S. J., 236.Nelson, W. K., 103.Neptune, J. A., 54.Nerdel, F., 154, 158.Nervik, W., 372.Nes, W. R., 228.Nesbitt, D. S., 140.Ness, R. K., 168, 259.Nethercot, A. H., 12.Neuberger, A., 234.Neudorffer, J., 236.Neumann, F. W., 370.Neumann, H. M., 54.Neumann, P., 321.Neumuller, G., 288.Neurath, H., 272, 274.Neuss, N., 249.Neville, G.A., 254.Newbold, G. T., 171.Newcombe, A. G., 371.Newman, M. S., 154, 155,Newth, F. H., 257,258,266.Newton, G. G. F., 238, 269.Newton, L., 327.Newton, S. A., 359.Newton, T. MT., 100.Neyman, M. B., 110.Nicholls, G. A., 195.Nicholls, R. V. V., 131.Nichols, M. L., 347.Nichols, R., 115.Nicksic, S. W., 186.Nickson, A., 164.Niclause, M., 47.Nicolai, E., 330.Niebylski, L. M., 104.Nielsen, A. H., 9.Nielsen, H. H., 9, 11.Nielsen, J. R., 12, 14.Nielsen, N . C., 104.Nielsen, S., 274.Nielson, E. D., 223.Niemann, C., 182, 185.Nightingale, D. V., 175.Nijboer, B. R. A., 81.Nijkamp, H. J., 374.Nikol’skaya, L. E., 49.Nikuni, Z., 294.171, 233.Nineham, A. W., 145.Noble, L.A., 368.Noble, P., jun., 128.Noggle, G. R., 372.Noland, W. E., 126.Noll, W., 75.Nolte, E., 242.Noordhof, G. H., 367.Norberg, E., 297.Nord, F. F., 159.Nordman, C. E., 94.Nordmann, J., 318.Nordstrom, C. G., 368.Norris, F. W., 325, 329,331Norris, T. H., 49.Norris, W. P., 133, 375.Norrish, R. G. W., 22, 38,44, 58, 60.Northcote, D. H., 290.Norton, D. G., 126.Norton, E., 361.Nonvitz, G., 339, 359, 364,Novelli, G. D., 245, 301,Noyce, B. N., 301.Noyce, D. S., 164, 202.Noyes, R. M., 43, 49, 133.Noyes, W. A., 44, 47.Nozaki, H., 172.Nozoe, T., 192.Nuckolls, R. G., 11.Nudenberg, W., 146.Nussbaum, A. L., 249, 291.Nutten, A. J., 352, 358.Nyholm, R. S., 54, 89, 117,Nyman, C. J., 94.Oae, S., 140.Oakwood, T.S., 14.Oberkobusch, R., 188, 242.O’Brien, C. J., 30, 89.O’Brien, J . F., 187.Ochiai, E., 239.Ochoa, S., 302, 303, 313.Ockenden, D. W., 242.O’Colla, P., 292, 326, 328,O’Connor, P. R., 197.O’Connor, R. T., 182.O’Dea, J. F., 149.O’Donnell, M., 243.O’Dwyer, M. F., 15.Oesper, R. E., 349.Osterholm, K., 363.Oetjen, R. A., 11, 12, 15.Ogawa, T., 347.Ogg, R. A., 39, 44, 46.OhEochdha, C., 324.Ohinata, K., 242.Ohlberg, S. M., 110.Oken, A., 205.Olcott, H. S., 264.Oldham, J. W. H., 257.Oldham, K. B., 360.Oliver, G. D., 89.365, 366,304.340.329.Oliver, J. R., 121.Oliveto, E. P., 169, 229.Olivier, C., 266.Ollis, W. D., 243.O’Loane, J. K., 15.Olson, A. R., 143.O’Neill, R. C., 175.Onishi, H., 364.Ono, S., 84, 85.Onsager, L., 83.Onstott, E.I., 100.Ookawa, A., 82.Oparin, A. I., 286.Openshaw, H. T., 248.Opfer, H., 356.Oppenheim, I., 82.Oppenheimer, M., 312.Orchin, M., 117, 188.Oreskes, I., 373.Orgel, L. E., 13.Oroshnik, W., 141, 176.Orr, A. P., 327.Orr, R. J., 52.Orr, S. F. D., 246.Orten, J. M., 290.Orton, K. J. P., 131.Osbond, J. M., 226.Osborn, G. H., 372.Osborn, M. J., 309, 311.O’Shaughnessy, M. T., 57.O’Shea, C. J., 46.Ossorio, R. P., 143.Oster, G., 363.Oswin, H. G., 27.Othmer, D. F., 65.Ott, c . , 345.Ott, H., 165.Ott, W., 234.Ottesen, M., 275.Otting, W., 181.Dttmann, G., 176.Duchi, K., 65.Duellet, C., 34.Dughton, J. S., 224.Durisson, G., 208, 209, 232.herberger, C. G., 39, 60,Dverend, W.G., 257, 260,3wen, L. J., 159.]wen, L. N., 164, 174, 176,202, 203, 253.3wens, H. S., 289, 372.%a, T. M., 106.h a , V. T., 106.3zawa, T., 377. ’3201, Y. K., 353.Pachter, I. J., 242.Packham, D. I., 372.Pacsu, E., 257.Paddock, N. L., 167.Paillard, H., 170.Painter, E. P., 277.Palilla, F., 365.Palilla, F. C., 366.Palland, R., 336.145.263INDEX OF AUTHORS’ NAMES. 399Palmer, J. F., 359.Palmer, K. J., 370.Pan, C. Y., 14.Pandow, M. L., 51.Paneth, F. A., 89.Pappenhagen, J. M., 363.Pappo, R., 167, 220, 227,Papucci, R. A., 349.Paris, R. A., 359.Park, J. D., 187.Parke, M., 323.Parke, T. V., 238.Parker, C. A., 43.Parker, R. E., 129.Parker, W. G., 23.Parks, T. D., 351.Parlin, R. B., 65.Parr, R.G., 33.Parravano, G., 116.Parry, E. P., 361.Parry, R. W., 90, 340.Parthasarathi, K., 354.Partridge, S. M., 279, 372.Paschke, R. F., 182.Pascual, J. N., 365.Pasovskaya, G. B., 362.Pasternack, R., 201.Pasternak, R., 132.Pasteur, L., 152.Pataki, S., 232.Patrick, A. D., 298.Patrick, J. B., 169, 242.Patterson, J. A., 126.Pattison, F. L. M., 187.Patton, A. R., 375.Patwardhan, V. N., 182,Paul, D. E., 63.Paul, P. F. M., 167.Paul, R., 97, 169, 171.Pauling, H., 111.Pauling, L., 33, 179.Paulson, J. C., 171.Pausaclter, K. H., 145, 149.Pauson, P. L., 118.Pavlov, S. A., 31.Pavlyuchenko, &I. M., 74.Payne, C. C., 170.Payne, D. S., 107.Pazur, J. H., 284, 288, 292,Peacock, R. D., 110.Peal, W. J.. 332.Peanasky, R., 317.Pearl, I.A., 198.Pearlson, W. H., 187.Pearsall, H. W., 126.Pearson, R. G., 54, 55, 120,Pease, L. E. D., 99.Pease, R. N., 40.Pease, S. W., 356.Peat, S., 288, 289, 292, 298,299, 300, 323, 325, 327.Peavler, R. J., 111.Peckham, P . E., 205.243.374.295.138.Pecsok, R. L., 340, 342, 359Pedler, A. E., 38.Peebles, L. H., 59.Peeling, M., 125.Peetz, U., 112.Pelletier, S. W., 253.PBnasse, L., 273, 274.Pendergast, J., 312, 314Penfold, A. R., 207.Penfold, B. R., 239.Penman, D. R., 150.Penneman, R. A,, 13.Penner, S. S., 16, 23.Pennington, F. C., 143, 238Pennington, R. E., 32, 233Penther, C. J., 357.Pepkowitz, L. P., 376.Peppard, D. F., 373.Pepper, I(. W., 372.Perchowicz, Z., 189.Percival, E. E., 258, 327.Percival, E.G. V., 322, 323324, 325, 327, 328, 329.Percival, TV. C., 175.Perey, M., 374.Perio, P., 112.Perkin, W. H., jun., 205.Perkins, L. R., 339.Perkins, &I., 361.Perret, A, 147.Perrin, C. H., 357.Perrin, M. W., 36.Perros, T. P., 121.Perry, R., jun., 138.Persson, B., 291, 294, 295.Peshkova, V. M., 362.Pesson, M., 245.Peters, J. P., 314.Peters, R. H., 195.Peterson, D. H., 222, 223.Peterson, E. A., 320.Peterson, R. E., 366.Petley, J. E., 367.Petracek, F. J., 249, 252.Petrikova, M. N., 343.Petrova, A. N., 299.PetrB, F., 210.Petry, R. C., 65.Petrzilka, Th., 249.Petsch, G., 169.Pettit, R., 198.Pfab, W., 117.Pfeiffer, H. G., 363.Pfeiffer, P., 90.Pfeil, E., 150.Pfister, K., 278.Pflanz, L., 273.Pfluger, R., 236.Pflugmacher, A., 116.Phadke, R., 243.Phares, E.F., 318.Phatak, S. S., 182, 374.Philbin, E. M., 243.Phillips, C. S. G., 372.Phillips, D. D., 190.Phillips, G. O., 266.319.Phillips, J. D., 256, 372.Phillips, J. P., 371.Phillips, L., 79.Phillips, L. L., 296.Phillips, R. F., 74.Phillips, T. R., 78, 115.Piano, M., 375.Pickering, W. F., 341, 374.Pickles, D., 341.Pickles, W., 150.Pickworth, J., 10.Pierce, J. G., 268, 269.Pierce, 0. R., 187.Pietsch, R., 349, 366.Pifer, C. W., 377.Pigman, W., 263, 264.P i p e t , A., 291.Pijck, J., 345.Pike, R. A., 203.Pilgrim, F. J., 201.Pillow, M., 22.Pilz, W.. 341.Pinajian., J. J., 376.Pinchas, S., 14.Pines, H., 201.Pinkerton, J. M. M., 34.Pinner, S.H., 60.Piper, S. H., 182.Pirson, E., 205.Pirt, S. J., 288.Pister, H. J.. 172.Pitt-Rivers, R., 276.Pitzer, K. S., 14, 15, 56,202, 216.Plane, R. A., 50.Plate, E., 261.Plattner, E., 340.Plattner, P. A., 208.Plaut, G. W. E., 316.Plesch, P. H., 62, 63.Pliva, J., 207, 208.Plongeron, R., 268.Plust, H., 106.Plyler, E. K., 10, 12, 13.Pogell, B. M., 266.Pohl, F. A., 367.Pohlemann, H., 106.Pokras, L., 345.Polansky, J., 214.Polanyi, J. C., 26, 32, 39, 41.Polgar, A., 179.Polgar, N., 174, 182, 183.Pollard, A., 256, 372.Pollard, A. G., 329, 334.Pollard, A. J., 356.Pollard, F. H., 38, 103, 107,Pollard, W. G., 63.Polo, S. R., 12.Polonovski, M. , 245.Polya, J. B., 178.?omatti, R. C., 367.?ommer, H., 193.?onniah, L., 243.?onomareva, E.N., 378.?oole, A. G., 185.?ooIe, H. G., 20.370, 374400 INDEX OF AUTHORS’ NAMES.Poos, G. I., 170, 219.Popel, S. I., 75.Popenhoe, E. A., 265, 265,PopjAk, G., 231, 309.Pople, J. A., 83, 84.Poplett, R., 143.Poppelsdorf, F., 280.Porath, J., 269.Porteous, J. W., 374.Porter, C., 94.Porter, G., 22,23,38,44.Porter, G. B., 42.Porter, H. K., 287.Porter, R. F., 31.Porter, R. R., 279.Portz, W., 158, 262.Posener, D. W., 12.Posey, F. A., 120.Posner, A. M., 51.Post, B., 370.Post, H. W., 358.Posternak, T., 266.Potapenko, C. W., 75.Potocki, R., 31, 106.Potter, A. L., 289, 291.Potter, V. R., 312.Pouradier, J., 376.Powell, A. D. G., 212.Powell, W. A,, 367.Pradham, M. K., 211.Praj11, P.F. G., 93.Pratesi, P., 162.Pratt, R., 335.Pratt, R . J., 172.Preiser, A. E., 366.Preitner, G., 280.Prelog, V., 146, 149, 159,160, 173, 202, 203, 210,245, 253.Preobrazhenskiy, N. A., 206,247.Preston, R. D., 330.Prevost, C., 140.Pr4vot-Bernas, (Mme.) A.,Price, E. F., 356.Price, G. R., 367.Price, J . R., 249.Price, W. C., 17, 21, 42, 60,Pricer, W. E., 303.Pridham, J. B., 253, 367.Priest, G. G., 355.Prigogine, I., 83, 84, 85, 86,Prijs, B., 237.Prince, R. H., 350.Printy, H. C., 242.Prior, A. P. 375.Pritchard, H. O., 26, 39, 44.Priznar, M., 165.Probstein, R. F., 72.Proctor, B. E., 64.Proctor, J. S., 344.Prodinger, W., 339, 363.Proom, H., 373.269.70.175, 233.88.Proskuryakov, X. I., 291,ProStenik, M., 186.Prout, E.G., 73, 77.Prout, F. S., 175.Pucheault, M. J., 69.Pudles, J., 174, 153, 184.Pugh, W., 99, 104, 107, 352.Pummer, W. J., 228.Pummerer, R., 152, 205.Pungor, E., 351.Purchase, M., 143.Purishottam, A,, 349.Puterbaugh, W. H., 172.Quadbeck, G., 238.Quant, A. J., 133.Quartey, J. A. K., 227.Quastel, J. H., 312, 317.Queckenstedt, H., 321.Quimby, 0. T., 370.Raaen, V. F., 56.Raaflaub, J., 308.Raal, F. A., 42.Rabat6, J., 281.Rabideau, S. W., 48, 113.Rabinovitch, B. S., 167.Rabinowitch, E. I., 330.Rabjohn, N., 356.Racker, E., 260.Radhakrishna, P., 372.Raeithel, A., 188.Ratz, R., 106.Raffelson, H., 219.Rafique, M. C., 263.Ragetli, H. W. J., 331.Rajagopalan, D., 243.Rallings, R.J., 167.Ralls, J. W7., 221.Ralph, B. J., 213.Ramakrishnan, C. V., 304.Ramaniah, M. M. V., 366.Ramaniah, 33. V., 104.Ramirez, F., 164.Ramirez Muiioz, J . , 364.Ramsay, D. A., 17, 23, 43,Ramsey, J . B., 51.Ramsey, W. J., 52.Rand, M. C., 361.Rangarajan, M. A., 371.Rank, D. H., 9, 12, 13, 14.Ransford, J. E., 363.Rao, B. I?., 18.Rao, C. L., 374.Rao, D. S., 358.Rao, G. G., 359.Rao, K. R., 157.Rao, R. V. G., 65.Raper, H. S., 320.Raphael, R. A., 165, 194,Rapoport, H., 246.Rapp, L. R., 95.Rappen, L., 188.Rasp& G., lSl.294.218.204, 261.Rastrup-Andersen, J., 10,Rathgeb, P., 288.Rathjens, G. W., jun., 201.Rau, B., 119.Rau, W., 175, 196.Raulins, R., 197.Rausser, R., 229.Rawlinson, S. B., 130.Ray, G., 375.Rgy, H.N., 349.RAY, P., 91, 107, 116.Ray, S. C., 375.Raymond, R., 357.Raymond, W. H. A., 364.Razoulz, R. I., 80.Razuvaey, G. A., 98.Read, J., 204.Read, W. T., 71.Rebbert, R. E., 41, 42.Rebenfeld, L., 257.Rebertus, R. L., 94.Rebstock, M. C., 277.Recknagel, R. O., 312.Redfield, R. R., 279.Reed, L. J., 238.Rees, A. H., 250.Rees, K. R., 308.Reese, R. RI., 25.Reeves, L. W., 74.Regan, C. M., 137, 142.Regna, P. P., 201, 261.Reich, H., 232.Reichert, E., 302.Reichl, E. R., 374.Reichstein, T., 216, 232,Reid, D. H., 188.Reid, E. B., 207, 208, 215.Reid, E. F., 168.Reid, S. A., 337.Reid, S. G., 371.Reid, T. L., 242.Reid, T. S., 187.Reilley, C. N., 361, 362.Reilly, D. M. C., 339.Reimer, C. C., 347.Reineke, L.M., 222, 223.Reindel, F., 279, 371.Reinhardt, W. O., 314.Reischl, K., 349, 355.Reiss, K. P., 176.Rcissmann, T. L., 356.Reith, W. S., 275.Reithel, I?. J., 266.Rcitsema, R. H., 204.Remmert, L. F., 351.Renes, P . A., 100.Renz, J ., 232.Reppe, W., 172.Resch, A., 358.Resnick, C., 278.Kessler, C., 268, 269.Reuter, R., 101.Revinson, D., 363.Rex, O., 374.Reyes, A., 269.12.259INDEX OF AUTHORS’ NAMES. 401Reynolds, C. A., 360Reynolds, G. F., 360, 361.Reynolds, R. D., 197.Reynoso, J., 249.Rhinehammer, T. B., 347.Rhoads, S. J.. 197.Rhodes, D. N., 264.Ricciuti, C., 147, 361.Rice, F. A. H., 328.Rice, F. O., 105, 106, 107.Rice, H. M., 272.Rice, L. M., 168.Rice, 0. K., 36, 87.Rich, R. L., 48.Richards, E.L., 169, 261,Richards, G. N., 257, 260,Richards, R. E., 15, 17.Richardson. M. R., 353.Richter, J. W., 270.Richtmyer, N. K., 261.Rick, H., 205.Ridd, J . H., 127.Ridge, &I. J., 148.Riecke, K., 242.Riegel, B., 227.Rieger, M., 159.Riehl, L., 105.Rieman, W., 338, 372.Riemschneider, R., 203.Riethmuller, H.-U., 368.Rifkin, E. B., 32.Rigby, W., 210.Rigg, T., 68.Rila, W., 369.Riley, D. P., 271.Riley, J. P., 363.Rimington, C., 234.Rinehart, B. L., 172.Ringbom, A., 363, 365.Ringer, A. I., 317.Ringold, H. J., 169.Iiiniker, B., 211.Ripley-Duggan, B. A., 364.Risberg, E., 20.Riser, A., 204.Rist, C. E., 262, 263.Rittenberg, D., 308, 318.Ritter, D. M., 95.Rivera, J., 226.Rix, H. D., 12.Rizzolli, O., 355.Robb, J .C., 41, 42.Roberts, C. W., 268.Roberts, E. K., 40.Roberts, J., 79.Roberts, J . C., 194.Roberts, J . D., 129, 131,137,140, 142, 187, 301, 203.Roberts, J . S., 25.Roberts, P. J . I- ., 288. 292.Roberts, R., 41, 45.Roberts, R. M., 135.Robertson, A., 146, 212,Robertson, G. J., 257.266.323.213, 215.REP.-VOL. LRobertson, J. Rf., 125, 154Robertson, P. W., 127, 128Robertson, R. E., 55.Robertson, R. H. S., 75.Robertson, W. G. P., 204.Robins, P. A., 202, 213.Robinson, C., 271.Robinson, C. H., 224.Robinson, C. N., 169.Robinson, C. S., 310.Robinson, D. S., 157.Robinson, D. W., 104.Robinson, D. Z., 16.Robinson, G. C., 192.Robinson, G. W., 12, 19.Robinson, J. W., 347.Robinson, I<.L., 340.Robinson, P. L., 115, 120.Robinson, (Sir) R., 158, 169182, 183, 219, 231, 241,245, 251.Robinson, R. J., 361, 364.Robison, M. M., 143.Robson, A., 279.Robson, W., 280.Rocard, Y., 88.Roche, J., 276, 330, 335.Rochow, E. G., 103, 104.Rodden, C. J., 339.Rodebush, W. H., 24.Rodgman, A., 364.Rodina, M. V., 344.Roe, A., 199.Roe, E. M. F., 245.Roe, H. R., 369.Roder, H., 146, 170.Roedig, A., 177.Rodstam, G., 65.Rohm, E., 238.Roessler, W. G., 255.Rogers, D., 209.Rogers, L. B., 338, 348, 360,361. 365. 377.207.129, 130.Rogers, M.. A. T., 148.Roaier, E. R.. 220.Rogina, B., 377.Roginskij, S. Z., 74, 76, 77,Rohatki, K. K., 45.Rohrmann, E., 218.Rojas, G., 269.Roka, L., 224.Rolfe, J. A., 13.Rolfson, S.T., 244.Rollefson, A., 16.Rollefson, G. K., 47.Romero, M. A., 229.Romo, J., 229.Romojaro, F., 354.Rooney, C. S., 264.Roos, G., 109.Roos, H., 117.Ropp, G. A., 56.Rose, F. L., 238.Rose, H. A., 356, 369, 370.78.Rose, H. J., 373.Rose, J. E., 364.Rose, R. C., 328.Roseman, S., 256.Rosen, L., 263.Rosenblum, D. M., 109.Rosenburg, D. W., 170, 225.Rosenkrantz, H., 232.Rosenkranz, G.. 169, 170,226, 227, 229.Rosenmund, I<. W., 169.Rosenthal, C., 313.Rosenthal, J. E., 18.Rosenthal, N. R., 280.Rosenthal, R., 233.Rosenthaler, L., 356.Rosner, M., 208.Ross, A. G., 322, 323, 324,Ross, A. M., 370.Ross, J. H., 369.Ross, M., 66.Ross, M. H., 259.Ross, W. A., 162, 211,Rosselet, J. P., 266.Rossi, M. L., 355.Rossi, P.F., 371.Rossotti, H. S., 90, 340.Rotenberg, D., 23, 34, 30.Roth, M., 212.Rothschild, W. G., 66.Rouser, G., 185.Rousset, A., 18.Rovery, M., 272, 273, 274.Rowbottom, J., 68.Rowden, R. W., 87.Rowlinson, H. C., 22.Rowlinson, J. S., 80, 83,Roxburgh, C. M., 261.Roy, D. K., 291, 294, 299.Roy, R., 113.Rubinstein, K., 375.Rudesill, J. T., 143.Rudinger, J., 161.Rudman, D., 157.Rudra, S., 367.Rudorff, W., 112, 353.Rueff, L., 302, 303, 306.Ruiger, L. J., 11.Rulfs, C. L., 362.Rundell, J . T., 285.Runge, F., 188.Rusch, H. P., 148.Rushbrooke, G. S., 81, 82,Russell, A. S., 32.Russell, C. S., 234.Russell, K. E., 38, 58.Russell-Wells, B., 331.Ruyle, W. V., 170, 225.Ruzicka, L., 204, 211, 214.Ryabchikov, D., 372.Ryan, D.E., 349, 350.Ryan, J. P., 197.Ryason, P. R., 128.Ryder, B. L., 240.325.84.85, 86.402 INDEX OF AUTHORS’ NAMES.Rydon, H. N., 157, 171,208, 240, 272, 323, 325.Rygh, O., 333.Rylander, P. N., 143.Ryley, J. F., 290.Rynninger, R., 368.Saad, K. N., 289.Sabo, E. F., 228.Sacco, A., 120.Sachs, G., 344.Sadek, F. S., 351.Saemann, R., 274.Safford, H. W., 363.Saharia, G. S., 203.Sahasrabudhey, R. H., 65.Saifer, A., 373.St. Andr6, A. F., 219.St. John, G. E., 9.Saito, E., 140.Saito, S., 284.Sakami, W., 313, 314, 317.Saksena, B. D., 12.Salah, M. K., 178.Salander, R. C., 375.Salg6, E., 359.Salmon, J. E., 372.Salomon, H., 320.Salooja, K. C., 361.Salsburg, 2. W., 81, 82, 84.Saltzman, I3. E., 364.Salutslry, M.L., 346.Sammul, 0. K., 168.Samokhvalov, G. I., 206.Samson, S., 362.Samuel, A. H., 87.Samuelson, O., 372.Sanadi, D. R., 313.Sanchez Serrano, E., 376.Sandell, E. B., 121, 364,366, 373, 377.Sandeman, I., 109.Sanders, T. H., 255.Sanders, T. M., 12.Sanderson, J. J., 175.Sandoval, A., 227.Sanfilippo, S. J., 232.Sanftner, R. W., 358.Sanger, F., 270, 271, 274.Sankaranarayanan. K. M.,Sankegowda, H., 359.SanniC, C., 169.Sarett, L. H., 170, 219.Sargent, J., 164.Sargent, J, W., 377.Sargeson, A. M., 121.Saroff, H. A., 280.Sarolea, L., 83, 84, 86.Sarolea-Mathot, L., 86.Sato, T. R., 375.Saucy, G., 212.Sauerbrunn, R. D., 121,366,Sauermilch, W., 239.347.Seealso Mathot-Sarolea, L.and Sarolea-Mathot, L.377.Saulnier, J., 368.Saunders, B.C., 113.Saunders, D. F., 64.Saunders, T. M., 11.Saunders, W. H., jun., 264.Sauvageau, C., 329.Savat, C. S., 58.Sax, S. M., 166.Saxton, J. E., 241.Sayigh, A,, 135.Saylor, J. H., 367.Sayre, D., 219.Scadden, E. M., 373.Scandrett, F. J., 357.Scarf, H., 63.Schafer, F., 167.Schafer, H., 89, 116.Schafer, K., 364.Schaeffer, A., 352.Schafer, H. N. S., 92.Schaffer, F. L., 362, 363.Schaffer, N. K., 271.Schaffert, R. R., 368.Schatz, P. N., 16.Schaub, R. E., 251, 265.Schawlow, A. L., 11.Scheer, I., 218.Scheibl, F., 355.Scheidt, F. M., 148.Schenck, G. O., 235.Schenck, J. R., 177.Schenck, R. T. E., 233, 338.Schenk, H. R., 211.Schenk, P. W., 108.Schenker, H. H., 372.Schenker, K., 146, 149, 203.Scheraga, H.A., 28, 45, 280,Scheri, M. A., 233.Scheuer, I?. J., 242.Schigol, M. B., 362.Schiller, G., 319.Schindler, O., 259.Schinz, H., 205.Schinzel, E., 149, 196.Schlamowitz, M., 290.Schleicher, A., 377.Schlenk, F., 244.Schlesinger, A. H., 138.Schlesinger, H. I., 95, 96,97, 99, 115, 169.Schlicht, R. C., 264.Schlittler, E., 249.Schlogl, K., 374.Schlossnagel, F., 108.Schmall, M., 377.Schmerzler, G., 274.Schmets, J., 61.Schmid, H., 170, 197, 244.Schmid, K., 197.Schmidle, C. J., 171.Schmidlin, J., 226.Schmidt, C., 327.Schmidt, F., 320.Schmidt, H., 336.Schmidt, 0. T., 158.Schmitt, J. A., 56.347.Schmitz, E., 90.Schmitz, R., 140.Schmitz, W. R., 236.Schmitz-Dumont, O., 11 1.Schnakenberg, G.H. F., 238.Schneider, F. E., 79.Schneider, G., 272.Schneider, J. J., 228.Schneider, M. C., 303.Schneider, W. C., 302.Schneider, W. G., 87.Schneider, W. P., 226.Schneyer, L. H., 294.Schnizer, A. W., 176.Schnurmann, R., 366.Schoenewaldt, E. F., 135.Schoenheimer, R., 308.Schoniger, W., 358.Schoning, F. R. L., 75.Schofield, K., 242.Scholler, K. L., 163.Schomaker, V., 153.Schram, E., 372.Schramm, G., 273.Schrauzer, G. N., 347.Schreiber, K. C., 135, 136,Schroeder, D. C., 241.Schroder, H., 115.Schroeder, W., 272.Schroeder, W. A., 179, 272,Schroeter, G., 190, 203.Schubert, J., 317.Schuele, W. J., 91.Schiiler, H., 65.Schuerch, C., jun., 198,Schuette, H. A., 186.Schuetz, R. D., 359.Schufle, J.A., 101.Schulek, E., 351.Schuler, R. H., 42, 65.Schulte, J. W., 65.Schulte, K. E., 176.Schulz, G., 106.Schumann, H., 100.Schumb, W. C., 102.Schusdek, A., 310.Schuster, D., 109.Schute, J. B., 371.Schwartz, A. M., 95.Schwartz, D., 146.Schwartz, H. M., 273.Schwarz, B., 267, 289.Schwarz, M., 187.Schwarz, S., 367.Schwarz, V., 371.Schwarzenbach, G., 90, 93,Schwauwecker, H. E., 15.Schweitzer, J. E., 350.Schwimmer, S., 264, 293,Schwob, Y., 75.Scoins, H. I., 81, 82, 86.Scotoni, R., 227.Scott, A. D., 143.138.275.342.294, 295, 297JNDEX OF AUTHORS’ NAMES. 403Scott, A. I., 155.Scott, C. B., 134.Scott, D., 294.Scott, D. W., 32, 233.Scott, J. A., 196.Scott, J. J., 234.Scott, M. K., 232.Scott, R.L., 115.Scrivastava, H. C., 253.Searcy, A. M., 223.Searcy, A. W., 111, 116.Sears, C. A., 175.Secor, G., 284, 287.Sedlmeier, J., 117.Seebeck, E., 253.Seel, F., 105.Segal, E., 362.Seitzer, W. H., 66.Seligman, H., 375.Selim, A. S. M., 280.Sell, H. M., 368.Semenchenko, V. K., 88.Sen, B., 365.Sen, B. N., 374.Sen, D., 107, 116.Sengupta, P., 205.Senyavin, M. M., 372.Serfass, E. J., 370.Serin, P. A., 368.Serota, S., 232.Serres, C., jun., 164, 202.Seshadri, T. R., 243.Sethna, S., 243.Settele, W., 256, 288, 289.Setton, R., 31.Seubert, W., 303.Seubold, F. H., jun., 33,Seybold, A., 332.Seyfang, A. P., 376.Seyferth, D., 103, 104.Sha, Y.-H., 335.Shafer. P. R., 250.Shafizadeh, F., 260.Shah, G. D..358.Shalek, R. J., 69.Shalgosky, H. I., 361.Shankar, J., 374.Shannon, J. S., 204, 205.Shantarovich, P. S., 110.Shapiro, B., 303, 309.Shapiro, D., 185, 186, 277.Shapiro, I., 94, 98, 312.Shapiro, M. Y., 365.Shapovalov, Y. M., 49.Sharma, D., 12.Sharon. N., 264.Sharpe, A. G., 121, 128.Shaver, K. J., 342.Shaw, B. L., 177.Shaw, G., 240.Shaw, K. N. P., 277.Shaw, W., 309.Shechter, H., 152, 201.Sheehan, J . C., 175, 202,Sheft, I., 95, 113, 351.144, 148.237.Shemin, D., 234, 3G3.Shephard, R. R., 173.Shepherd, D. M., 375.Shepp, A., 37, 94.Sheppard, H., 232.Sheppard, J . C., 48.Sheppard, N., 12, 13, 14.Sheridan. J., 10, 28, 369.Sherman, R. E., 367.Shimanouchi, T., 12.Shinagawa, M., 361.Shiner, V., jun., 133.Shiner, V.J., jun., 133,Shingalri, T., 57.Shipley, R. A., 313.Shipman, W. H., 365.Shirahama, K., 331, 332.Shirley, E. L., 376.Shmuk, E. I., 77.Shoppee, C. W., 138, 167,227, 229, 230, 332.Shorland, 1;. B., 182.Short, L. N., 117, 240.Shreeve, W. W., 317.Shulek, E., 353.Shuler, K. E., 17, 23.Shuler. R. 11.. 49.Shull, E. R., 9, 12, 13, 14,Shyluk, W. P., 266.Sibbett, D. J., 43, 49.Sicher, J., 161.Siebel, H. P., 103.Siegel, A., 374.Siegel, S., 132, 202.Siegmann, C. M., 165.Sierra, F., 354.Siggia, S., 362.Silk, M. H., 177.Silveira, V., 289.Silverman, L., 364.Silverman, 0.. 366.Silverman, S., 10.Silverstone, G., 225.Simchen, A. E., 78.Simes, J . J . H., 212.Simha, R., 61.Simkins, R. J . J., 127.Simmons, G.A., 348.Simmons, H. E., 187.Simmons, H. E., jun., 129,Simmons, J . W., 12.Simmons, N. T., 357.Simmons, 0. W., 364.Simon, E. J., 303.Simon, O., 321.Simon, W., 365.Simonetta, M., 194.Simons, J., 38.Simons, J. H., 32, 114, 187.Simonsen, (Sir) J., 207, 208.Simpson, D. M., 15.Simpson, J . C. E., 214.Simpson, M. E., 270.Simpson, T. H., 215.149.98.201.Sims, P., 145, 174.Singer, B., 273.Singer, K., 352.Singer, T. P., 291, 306.Singh, A., 350.Singh, R., 350.Singh, K.., 79.Singh, V. P., 355.Singley, R. J., 116.Sinwell, F., 149.Sirvetz, M. H., 12.Sisido, K., 172.Sisler, H. H., 99, 104, 105,Sistrunk, T. O., 121.Sita, G. E., 170, 225.Sixma, F. L. J., 55, 147,Sjoquist, J., 275.Sjostrom, A. G. M., 333.Skell, P.S., 133.Skellon, J. H., 147, 358.Skibina, E. M., 365.Skinner, R. G., 142.Skinner, H. A., 24, 25, 26,Skoog, D. A., 359.Skraba, W. J., 374.Skripov, V. P., 88.Skrube, H., 351.Slack, R., 145.Slater, N. R., 35.Slezer, M., 353.Slobodian, E., 276.Small, N . J . TI., 148.Small, P. A., 59.Smales, A. A., 376.Smart, C. L., 267.Srnedley-MacLean, I., 309.Smedvik, L., 10.Smets, G., 59, 61.Smirnova, I. I., 77.Smirnov-Zamkov, I. V., 201.Smit, J., 368.Smith, A. C., 103, 104.Smith, A. L.. 12.Smith, C., 25.Smith, C. R., 91.Smith, D. C., 12.Smith, D. C. C., 260.Smith, D. G., 11, 331.Smith, F., 254, 255, 263,266, 288, 290, 323, 327,371.Smith, G. F., 115, 142, 339,351, 356, 364, 365.Smith, G. H., 187.Smith, H.J., 140.Smith, I., 279, 374.Smith, J . C., 167, 181.Smith, J . F., 136, 186.Smith, J. W., 40.Smith, L., 30.Smith, L. W. L., 376.Smith, M. E., 91.Smith, N. B., 29.Smith, P. A. S., 133.109, 111.165.28, 29, 107404Smith, P. F., 165.Smith, R. C., 49.Smith, R. J., 361.Smith, R. L., 244.Smith, R. M., 12.Smith, R. P., 36.Smith, S. G., 276.Smith, W. T., jun., 195.Smith, W. V., 11.Smittenberg, J., 30.Smyth, I. F. B., 158.Snyder, H. R., 174, 199.Snyder, P. E., 30, 32, 93.Sober, H. A., 157.Sobin, B. A., 238.Sobotka, H., 168.Sorensen, N. A., 177.Solarek, J . F., 349.Sollman, P. B., 227.Solomons, I. A., 177, 238.Soloway, A. H., 169.Sommereyns, G., 356, 374.Sommereyns, J., 374.Somogyi, IT., 254.Sondheimer, F., 169, 170,176, 226, 227, 229, 233.Sonnenschein, W., 364.Soodak, M., 303.Soper, F.G., 105, 131.Soper, Q. F., 238Sorm, F.. 161, 207, 208.Sorof, S., 291.Soskin, S., 313.Sowden, F. J., 272.Sowden, J . C., 261.Sowden, R. G., 39.Spahr, P. F., 291.Spalding, F. F., 66.Spall, B. C., 39.Sparke, M. B., 165.Sparrow, C., 107.Spatz. S. M., 104.Specht, F., 338.Spedding, F. H., 100, 342.Speiser, R., 31, 89.Spencer, C . F., 203.Sperber, El., 205.Spero, G. B., 222.Spettel, E. C., 361.Spike, C. G., 90, 340.Spikes. J. D., 47.Spingler, H., 80.Spinks, J . W. T., 64.Spjridonova, A. I., 367.Spitzer, R., 202.Spitzy, H., 351.Spivey, E., 142.Sprain, W., 365.Sprecher, M., 135.Spreter, V., 65.Spriestersbach, D., 266.Spring, I;.S., 211, 214, 224Springall, H. D., 24, 31.Sproull, M., 367.Sribney, M., 245.Srikantam, B. S., 371, 373.261.)EX OF AUTHORS’ NAMES.jrivastava, S. P., 53.Staab, H. A., 173, 181.Stacey, M., 254, 256, 257,260, 265, 267, 300, 375.jtadie, W. C., 310, 311, 313,31 4.3tadler-Denis, A., 374.Stadtman, E. R., 302, 303,Stafford, G., 151.Stamm, H., 150.StanaCer, N., 186.Stancer, H. C., 184.Stanier, W. M., 256.Stansly, P. G., 303, 305,Stare, F. J., 301, 313.Stark, 1. E., 313.Stark, J . R., 372.Stauffacher, D., 253.Steacie, E. W. R., 39, 41,Stearns, E. J . , 362.jtedman, R. J., 274.Steele, B. R., 187.Steele, M. C., 362.Stein, G., 53, 68, 145, 353.Stein, R. S., 15.Stein, S. S., 282.Stein, W.H., 279.Steinbach, J. F., 340.Steinberg, D., 274.Steinberg, H., 49.Steinbergs, A., 367.Steindler, M. J., 95.Steinert, R., 193, 241.Steinhardt, R. G., 370.Stepanenko, R. N., 289.Stephen, W. I., 339, 352,Stephens, C. R., 201.Stephenson, O., 146.Stepukhovich, A. D., 39.Stern, J. R., 303, 306.Sternberg, H. W., 117.Stetten, Dew., 308.Stetter, H., 173.Stevens, B., 31.Stevens, C. L., 139.Stevens, H. C., 138.Stevens, H. M., 374.Stevenson, D. P., 24.Stevenson, P. C., 372, 373.Stewart, A. W., 334.Stewart, C. A., 37.Stewart, D. G., 191.Stewart, H. B., 315.Stewart, J . M., 233.Stichnoth, O., 155.Stickney, M. E., 363.Stine, C. R., 347, 362.Stitch, M. L., 12.Stites, J . G., 346.Stitt, F., 20.Stivers, E.C., 56.Stock, J. T., 339.Stockmayer, W. H., 59, 83306.308.42.358.Stoenner, R. W., 361.Storger, G., 110.Stoicheff, B., 11.Stoicheff, B. P., 9, 13.Stokes, C. S., 187.Stoll, A., 166, 232, 245, 249,Stolyarov, K. P., 343.Stone, A. L., 158.Stone, B. D., 54.Stork, G., 139, 202, 208,Storrie, A. J. S., 188.Stotz, E., 185.Stout, J . W., 33.Strachan, K. G. A., 346.Strachan, W. S., 224.Strafford, N., 341.Strahan, C. C., 340.Strain, H. H., 330, 334, 375.Strandberg, M. W. P., 12.Strang, A., 43.Strange, E. E., 368.Straumanis, M. E., 370.Streibl, M., 208.Streitwieser, A,, 162.Streng, A. G., 187.Streuli, C. A., 347, 361.Strickland-Constable, R. F.,Striclis, W., 362.Strijland, J., 88.Stripp, K. F., 82.Strock, L.W., 367.Strong, F. M., 181.Stroup, R. E., 11, 12.Struthers, G. W., 368.Stubbs, F. J., 39, 359.Stubbs, M. F., 101.Stuckey, R. E., 339.Stumpf, K. E., 346.Sturm, W., 98.Style, D. W. G., 30, 45.Suchow, L., 94.Sudo, E., 365.Siis, O., 242.Sugowdz, G., 240.Sullivan, J . C., 90.Sumi, M., 206.Sumitomo, H., 60.Summers, G. H. R., 138.Summerson, W. H., 271.Sumner, H. H., 195.Sumner, J. B., 287, 288.Sumrell, G., 173, 183.Sundaram, A. K., 373.Sunko, D. E., 186.Sunner, S., 30, 32.Surak, J . G., 374.Suschitzky, H., 195.Sussman, S., 171.Sutcliffe, D., 253.Sutcliffe, L. H., 21, 22.Sutherland, E. W., 297, 311.Sutherland, G. B. R. M., 15.Sutphen, W. T., 46.253.235.376.227INDEX OF AUTHORS’ NAMES. 405Suttle, J.F., 65, 358.Sutton, D., 50, 51, 105.Sutton, D. A., 147, 173, 181.Sutton, H. C., 67.Sutton, L. E., 10.Suzuki, N., 322.Suzutu, S., 378.Svanborg, K., 294.Svedberg, T., 65.Svoboda, M., 161.Svoboda, O., 363.Swain, C. G., 55, 134, 135,Swain, T., 368.Swan, J. M., 268, 278.Swanwick, J. D., 103.Swayne, R. E. H., 213, 214.Swedlund, B. E., 127, 130.Sweeney, T. R., 374.Sweet, T. R., 375.Sweetser, P. B., 341, 365.Swern, D., 147, 233, 361.Swidler, R., 235.Swift, E. H., 352, 354, 360.Swingle, S. M., 331.Swings, P., 22.Swistak, E., 171.Sworski, T. J., 70.Sykes, A., 343.Sykes, K. W., 119.Symons, M. C. R., 53, 151.Syrkin, Y. K., 49.Szamborska, W., 76.Szasz, G. J., 12.Szmuszkovicz, J., 167, 189,Szwarc, M., 24, 25, 26, 28,Tabei, I<., 332.Tabuchi, D., 62.Taggart, J.V., 301.Tahara, A., 206.Taimni, I. K., 343, 347, 349.Tait, P. C., 357.Takagi, M., 331.Takahashi, E., 331.Takamatsu, T., 65.Takano, I<., 281.Takaoka, K., 294.Takaoka, M., 332.Takebayashi, M., 57.Takeda, K., 214.Takemura, K. H., 169.Takimo, Y., 329.Tallan, H. H., 279.Talvitie, N. A., 366.Tammelin, L.-E., 364.Tanenbaum, S. W., 278.Tantranon, K., 354.Tappi, G., 334.Tarbell, D. S., 177, 233.Tarrant, P., 187.Tase, S., 331.Taskis, H. D., 148.Tatchell, A. R., 215, 263.‘rate, F. A., 60.142.220.35, 39.Taube, H., 48, 50, 51, 57,Tauber, H., 356.Tayler, F. M., 77.Taylor, C. G., 147.Taylor, D., 111, 163, 199.Taylor, H. A., 28, 46.Taylor, J.E., 149.Taylor, J. W., 39.Taylor, R. E., 187.Taylor, S. P., 268.Taylor, W., 52, 140.Taylor, W. I., 251.Tazuma, J. J., 170, 193.Tchelitcheff, S., 171.Tedder, J. M., 175.Teegan, J. P., 21.Tees, T. F. S., 29.Teicher, H., 347, 366, 372.Telep, G., 365.Temple, R. G., 147.Tepperman, H. M., 315.Tepperman, J., 315.Ter Haar, K., 341.Terrey, G., 343.Terriere, L. C., 320.Terry, E. A., 363.Terry, G., 104.Tetenbaum, S. J., 9, 10.Teuber, H.- J., 196.Tewari, J. D., 344.Thain, E. M., 245.Thaller, V., 178.Theilacker, W., 155.Theilig, G., 237.Theurer, K., 376.Thilo, E., 106.Thoma, R. W., 223.Thomas, A., 309.Thomas, B. R., 211.Thomas, G. H., 224.Thomas, G. J., 288, 289.Thomas, J. F., 245.Thomas, J. G. N., 78.Thomas, K., 319, 321.Thomas, P.T., 38.Thomas, R., 375.Thomas, S. L., 375.Thomas, W. J. O., 14, 15.Thomas, W. M., 57.Thompson, A. J., 101.Thompson, A. R., 274.Thompson, E. 0. P., 270,Thompson, H. W., 9, 10, 12,Thompson, J . I,., 223.Thompson, J . M., 339.Thompson, R., 29.Thompson, R. J., 40.Thompson, R. R., 291.Thornson, R. H., 198.rhomson, T. G. H., 327.Thorndike, A. M., 17.Thornton, S. D., 172.Thrush, €3. A., 22.rhruston, M. N., 147.120.273, 274.15, 16, 114.Thuring, P., 147.Thiirkauf, M., 259.Tickner, A. W., 34, 40.Tietjen, D., 178.Tietz, A., 309.Tietz, R. F., 248.Tikhomiroff, N., 371.Tillotson, A., 152.Tillu, M. M., 353.Tipper, C. F. H., 58, 144.Tiselius, A., 283, 331, 375.Tishler, M., 170, 225.Tobin, M.C., 14, 30.Tobolsky, A. V., 58, 59, 66.Todd, A., 61.Todd, A. R., 245.Todd, G., 207.Todd, W. R., 314.Todes, 0. M., 76.Toennies, G., 367.Toga, T., 206.Togasawa, N., 331.Tolberg, W., 182.Tolbert, B. M., 57.Tolman, R. C., 72.Tomasewski, A. J., 288.Tomiyama, T., 330.Tomiyasu, Y., 335.Tomkins, G. M., 232.Tomlinson, R. H., 62.Tompa, H., 62, 85.Tompkins, E. H., 74.Tompkins, F. C., 73, 76, 77,Tonkyn, R. G., 128.Topp, A. C., 100.Toralballa, G. C., 294.Toribara, T. Y., 367, 368.Torkington, P., 14.Torossian, R., 169.Torsueva, E. S., 110.Toseland, P. A., 275.Tousignant, W. F., 205.Towne, A. K., 345.Townes, C. H., 11, 12, 19.Townsend, J., 63.Trambarulo, R., 9, 10, 11.Trappaniers, N., 86.Trappe, G., 148.Trautmann, G., 236.Treacy, J.C., 37.Treadwell, W. D., 92.Trego, K., 364.Treibs, A., 234.Treibs, W., 146, 170, 193,Trenwith, A. B., 37.Trcssler, D. K., 327.Trevett, M. E., 238.Trevorrow. L. E., 120.Tribalat, S., 373.Trickett, J. C., 55.Trifan, D., 136.Trinder, P., 353.Trippett, S., 177, 268, 269.Tristram, E. W., 195.Trombe, F., 372.78, 79.205, 207, 241406 INDEX OF AUTHORS’ NAMES.Tronev, V. G., 116.Trotman-Dickenson, A. F.,Trowse, F. W., 55.Troxel, S. M., 24.Troxell, H. A., 241.Tsai, L., 236.Tsao, T. C., 280.Tsatsas, G., 160.Tschesche, R., 215, 245.Tseng, C. K., 327.Tsuchiga, R., 76.Tsuchiya, Y., 333.Tsujimoto, M., 331.Tsujimura, M., 332.Tswett, M., 378.Tuck, L. D., 97.Tull, F. A., 259.Tully, M.E., 170.Tuppy, H., 268, 279.Turkevich, J., 10.Turnbull, D., 71, 72.Turnbull, J. H., 202.Turner, D. S., 369.Turner, E. E., 126, 155, 156.Turner, H. S., 375.Turner, K. J., 61.Turner, R. A., 274.Turner, R. B., 216, 218, 229.Turnock, D., 374.Turton, C. N., 150.Tuttle, L. C., 303.Tutton, R. C., 42.TutundiiC, P. S., 360.Twigg, G. H., 52, 144.Tyczkowski, E. A., 113.Tyner, D. A., 221.Ubbelohde, A. R., 148.Udenfriend, S., 272.Udovenko, V. V., 362.Ueberwasser, H., 221.Uhle, F. C., 252.Uhlenbrock, J. H., 184.Uhrich, R., 152.Ulrich, H., 241.Ulrich, P., 259.Umemoto, S., 333.Underdown, R. E., 372.Underkofler, L. A., 291, 294,Underwood, A. L., 341.Ungnade, H. E., 368.Updegraff, I. H., 378.Upson, U.L., 350.Upton, A. M. C., 361.Uri, N., 52, 145.Urone, P. F., 361.U s h , R., 98.Utsumi, S., 377.Utter, M. F., 312.Uyeo, S., 251.Vaeck, S. V., 371.Vakulova, L. h., 206.Valentine, L., 59.39, 40, 44.299.Valet, G., 112.van Artsdalen, E. R., 28, 45.Van Baalen, J., 310.Van Bruggen, J. T., 310.Vance, E., 58, 59.Vance, J. E., 376.Van Cleave, A. B., 64.Van Cleve, J. W., 254.VanDalen, E., 361.Van der Heijde, H. B., 49.van der Kemp, F.-P., 375.van der Lee, J., 321.van der Meulen, P. A., 110.van der Neut, J. H., 184.VanderWerf, C. A., 140.van Dijk, H., 357.van Dranen, J., 88.VanDuuren, B. L., 250, 251.van Erkelens, P. C., 375.van Etten, C. H., 372.van Hove, L., 81, 83.van Ligten, J. W. L., 355.Van Nes, K., 30, 148.van Nieuwenburg, C.J., 355.Vanossi, R., 345.Van Panthaleon Van Eck,van Pinxteren, J. A. C., 358.Van Slyke, D. D., 314.van Straten, S. F., 131.van Tamelen, E. E., 192,Van Tiggelen, A., 23.Van Uitert, L. G., 91, 340.VanZyl, G., 233.Vasisth, R. C., 370.Vaughan, C. W., 129.Vaughan, G., 257.Vaughan, J., 79.Vaughan, W. E., 144.Vaughan, W. R., 138.Vegezzi, G., 356.Veibel, S., 148, 287.Veit, I., 152.Velasco, M., 226.Velick, S. F., 272, 297.Venet, A. M., 376.Venkatachallam, C. N., 371,Venkateswarlu, P., 10.Vennesland, B., 150, 161.Vercellone, A., 278.Verderame, F. D., 366.VereS, K., 207.Vergoz, R., 57.Verkade, P. E., 184, 321.Verma, M. R., 355.Vernon, C. A., 128, 131, 139,Verschelden, P., 13 1.Vestin, R., 92.Vetter, H., 172.Vial, J., 359.Vick, M.M., 343.Vickery, R. C., 339.Vincent, D., 294.c. L., 90.205, 235.373.141.Vincent, E., 34.Vincent, E. R., 23.Vinci, F. A., 339.Vioque-Pizarro, A., 345.Vischer, E., 223.Visco, L., 210.Viscontini, M., 266, 277.Volkl, E., 105.Voelz, F. L., 12.Voge, H. H., 25.Vogel, A. I., 359.Vogel, C., 253.Vogel, E., 194.Voigt, D., 106.Volcheck, H. D., 246.Volk, M. E., 301.Volkin, E., 245.Volman, D. H., 42, 46, 57.Volmer, M., 71.von der Bey, G., 181.von Gross, E., 266.Von Korff, R. W., 304.von Krakkay, T., 117.von Kutepow, N., 172.Vonnegut, B., 71.von Rudloff, E., 182.von Schivizhoffen, E., 358.von Wartburg, A., 232.von Wartenberg, H., 102,Voronkova, V.Y., 291.Voser, W., 211.Voss, G., 177.Vossen, G., 203.121.Wachtmeister, C. A., 267.Wada, T., 332.Waddell, W. R., 314.Waddington, G., 32, 233.Wade, H. E., 255.Wadelin, C., 373.Wadman, W. H., 266.Waelsch, H., 280.Wagland, A. A., 225.Wagle, D. S., 343.Wagle, S. S., 202.Wagner, R. B., 175.Wagner, R. I., 95, 106.Wagner, R. L., jun., 261.Wagner, R. S., 365.Wagner, W. F., 377.Wagner- Jauregg, T., 271.Wagreich, H., 342.Wahl, A. C., 48.Wahl, R., 206.Waight, E. S., 141.Wailes, P. C., 174.Wakefield, A. J., 86.Wakil, S. J., 304, 305.Walaschewski, E. G., 114,Walborsky, H. M., 187.Walden, M. K., 291.Waldron, D. M., 254.Waldron, N. M., 275.Waldschmidt-Leitz, E., 273.187INDEX OF AUTHORS’ NAMES. 407Walker, A.O., 97.Walker, J., 171, 202.Walker, T., 168.Wall, J . S., 372.Wall, L. A., 67.Wall, M. E., 232.Wallcave, L., 179, 180.Wallenfels, K., 284, 286.Waller, C. W., 265.Waller, J., 195.Walsh, A. D., 21, 22.Walter, J., 130.Walter, J. L., 348.Waly, *4., 69.Walz, D. E. 264.Wang, C. H., 58.Wankmiiller, A., 375.Wantier, G., 374.Wanzlick, H. W., 203.Warburton, W. K., 192.Ward, J., 371.Ward, W. M., 15.Wardlaw, W., 103.Warhurst, E., 22, 26, 27, 32,Waring. C. L., 367, 368.Warner, D. A., 187.Warren, J. W., 25.Wartik, T., 98, 99.Warwick, G. P., 150.Washbrook, C . C., 341.Washburn, E., 240.Wasif, S., 110.Wasley, W. L., 148.Wasserman, A., 55.Wassermann, H. H., 198.Wassink, E. C., 331.Watanabe, W., 142.Waters, W.A., 42, 52, 53,115, 126, 128, 142, 144,146, 148, 149, 150, 151,359.39, 41.Watjen, J . W., 238.Watson, W. F., 59, 62.Watt, I. C., 148.Watters, J . I., 92.Wawrzynek, W., 345.Wawzonek, S., 163.Weatherly, T. L., 12.Weaver, B., 100.Webb, E. C., 304.Webb, G. B., 238.Webb, I. D., 139.Webb, J. L. A., 158.Webb, R. F., 174.Webber, T. J.. 361.Weber, A., 12.Weber, D., 16.Weber, E. F., 108.Weber, H., 178.Weber, H. H., 92.Weber, L., 229.Weberling, R., 365.Weedon, B. C. L., 168, 170,173, 176, 177, 178, 180,181, 182, 201.Wehner, G., 93.Wehner, P., 116.Weibull, C., 272.Weidenfeld, L., 78.Weigel, M., 111.Weigner, E., 256.Weil, L., 271.Weil, R. M., 298.Weinberger, A. J . , 56.Weinberger, M. L4., 87.Weiner, H., 65.Weinhouse, S., 301, 302,309, 312, 313.Weintraub, A., 222.Weisblat, D.I., 244.Weisiger, J. R., 269.Weiss, A., 93, 101, 374.Weiss, H. G., 94, 98.Weiss, J., 51, 52, 68, 145.Weissbarth, O., 172.Weisser, H. R., 200.Weissmann, S. I., 63.Weisz, H., 343.Weitkamp, A. W., 173.Weitzel, G., 319, 321.Weizmann, A, 193.Weliky, V. S., 244.Weller, S., 50.Wells, A. J., 16.Wells, R. A., 89, 371.Welsh, H. L., 9, 11, 14.Welwart, Y., 367.Wender, I., 117.Wendler, N. L., 230.Wenkert, E., 242, 245.Wentorf, R. H., 81.Weyster, B. M., 163.Wermer, G., 170.Werner, E. A., 111.Werner, R. L., 15.Werner, W., 92.Wernet, J., 104.Wertheimer, E., 309.Wessely, F., 149, 196.Wessely, L., 306.West, E. S., 310, 314.West, G.B., 375.West, P. W., 343.West, R., 103, 120, 340.West, T. S., 359, 377.Westall, R. G., 234.Westermark, H., 30.Westheimer, F. H., 150,151, 159, 161.Westneat, D. F., 363.Westoo, G., 148.Weston, R. E., 12.Westrum, E. F., jun., 30.Wettstein, A., 223, 224,Weygand, F., 167, 244,Weymouth, F. J., 245.Whaley, W. M., 169, 247.Whalley, W. B., 243.Wheatley, P. J., 20, 23, 34.226.260.Wheeler, D. H., 182.Wheeler, T. S., 243.Wheelwright, E. J., 100,342.Whelan, W. J., 285, 288,289, 292, 294, 298, 299,300, 323.Whelan, W. P., jun., 135.Whiffen, D. H., 17, 254,Whipple, R. O., 118, 120,Whistler, R. L., 254, 256,White, A. M., 145.White, C. E., 366, 373.White, D., 32.White, E. A., 102.White, H. F., 23.White, J., 320.White, J.U., 23.?Vhite, J. W., 284.White, L. M., 284, 287.White, P. L., 92.White, T. T., 357.White, W. F., 270.White, W. N., 139.Whitehead, T. P., 375.Whitehouse, H. S., 165.Whiteker, R. h., 119.Whitelaw, S. P., 176.Whiteley, H. R., 319.Whiting, M. C., 176, 177.Whittle, E., 22, 27, 41.Wiberg, E., 98.Wiberg, K. B., 146.Wiberly, S. E., 364, 367.Wichmann, E. M., 1C6.Wick, A. N., 317, 320.Wickberg, B., 267.Wicke, E., 27.Wicks, L. F., 297.Widman, O., 198.Widoff, E., 333.Wieland, H., 313.Wieland, K., 31.Wieland, O., 306.Wieland, P., 221.Wieland, T., 271, 303, 300.Wiele, M. B., 372.Wiesner, K., 251.Wiggin, E. A , 375.Wiggins, L. F., 257.Wiggins, T. A., 9, 12.Wigglesworth, V. R., 312.Wijnen, N. H. J . , 2 S , 41,Wilbur, K. M., 148.Wilcox, W. S., 12.Wild, G. M., 255.Wilde, K. A., 65.Wildman, W. C., 221.Wilds, A. L., 169, 221.Wiles, L. A., 194.Wilfred, E., 210.Wilhelm, R., 65.266.340.267, 289.46408 INDEX OF AUTHORS’ NAMES.Wilkins, C. J., 103.Wilkins, D. H., 351, 364,Wilkins, R. G., 121.Wilkinson, G., 118.Wilkinson, I. A., 298, 300.Wilkinson, N. T., 352, 358.Will, F., 366.Will, G. M., 128.Willard, H. H., 339, 346,Willard, M. L., 356.Willavoys, 13. J., 74.\Villi, A. V., 55.Williams, D., 12, 26.Williams, D. E., 173.Williams, E. D., 150.Williams, E. F., 182.Williams, E. J., 37.Williams, G., 126, 127, 131,Williams, G. H., 266.Williams, H. L., 52.Williams, J., 233.Williams, J. H , 169, 226,251, 254, 265.Williams, K. T., 254.Williams, M. B., 364.Williams, Q., 28.Williams, R. J., 38, 132,Williams, R. J . P., 90, 283,Williams, R. I,., 9, 10.Williams, R. R., 42.Williams, V. A., 129.Willits, C. O., 147, 361.Wilmarth, W. K., 50.Wilmshurst, B. R., 26.Wilsdorf, H., 75.Wilshire, J. F. K., 190.Wilson, C. I,., 143, 338, 344,Wilson, D. W., 313.Wilson, E. B., 12, 16.Wilson, I. B., 272, 303.Wilson, L. D., 361.Wilson, M. K., 12.Wilson, W., 202.Windsor, M. W., 23.Winfield, M. E., 77.Winitz, M., 279.Winkelmann, G., 10 1.Winkler, C. A., 65, 131.Winram, B. C., 359.Winsch, J. O., 373.Winsor, G. W., 75.Winstein, S., 135, 136. 138,139, 140, 148.Winston, H., 126.Winter, R., 243.Winteringham, F. I?. W.,Winterstein, A., 181.Wintersteiner, O., 252.Winterton, R. J., 314.365.366.280.294.340.371, 377.373.Wirth, M. M., 147.Wirtz, R., 235.Wischin, A., 75.Wise, E. N., 360.Wise, H., 21, 27, 37.Wise, W. S., 52, 144.Vitkop, B., 145, 147, 169,Wittig, G., 95, 155.Wittwer, S. H., 368.Woiwod, A. J., 373.Woldring, M. G., 368.Wolf, G., 189.Wolf, V., 176.Wolfgang, R. L., 111.Wolfhard, H. G., 23.Wolfrom, M. L., 254, 259,264, 265, 266.Wolfsberg, M., 56.Wolkenstein, M., 18.Wolkowich, M. G., 147.Wollenberger, A., 275.Wollish, E. G., 377.Wolsky, S. P., 93.Wolstenholme, G. E. W.,Wolz, H., 260.Wood, A. A. R., 365.Wood, C. H., 362.Wood, D., 266.Wood, D. G. M., 152.Wood, D. J. C., 257.Wood, G. W., 224, 225.Wood, H. C. S., 248.Wood, H. G., 312, 317, 319,Wood, J. L., 143.Wood, L. G., 372.Wood, W. W., 81, 153.Woodall, N. B., 369.Woodham, A. A., 199.Woods, G. F., 212, 224,Woodward, F. N., 322, 323,Woodward, G. E., 259.Woodward, J. A., 376.Woodward, L. A., 13, 18.Woodward, P., 344.Woodward, R. B., 201, 228,231, 233, 261.Woodworth, R. C., 152.Woolaver, L. B., 78.Wooldridge, H. V., 350.Woolf, D. O., 241.Woolf, L. I., 256.Woolfson, M. M., 245.Woringer, P., 317.Worley, R. E., 22.Worthy, T. S., 113.Wotiz, J. H., 168.Wragg, W. R., 215.Wren, H., 160.Wright, F. J., 23, 44.Wright, G. F., 364.Wright, 0. L., 175.242, 249.280.321.225.324.Wright, P., 50, 105.Wright, R. S., 212.Wright, W. E., 375.Wright, W. W., 60.Wuentin, K.-E., 374.Wiirsch, J., 231.Wulf, 0. R., 17.Wyatt, G. M., 364.Wyatt, P. F., 364.Wyllie, G., 37.Wyman, L. J., 224.Wyshak, G. H., 210.WU, T.-Y., 22, 36,Yagi, Y., 335.Yalman, R. G., 119.Yamamoto, Y., 284.Yamane, K., 355.Yanagita, M., 206.Yancey, J . A., 137.Yang, N. C., 192.Yankwich, P. E., 56.Yates, P. C., 120.Yee, G. S., 314.Yehle, E. C., 338.Yoe, J. H., 348, 366.Yoffe, A. D., 79.Yohe, G. R., 148.Yosiki, S., 214.Yost, D. M., 52.Young, E. G., 322, 328, 320,Young, F. E., 369.Young, I?. G., 315.Young, G. T., 330.Young, J . A., 187.Young, R. G., 266.Young, R. S., 338, 346.Young, V. R., 331.Young, W. G., 136,139,140.Yu, S. T., 346.Yudowitsch, K. L., 370.Yuster, P. H., 376.Yvon, J., 81.331.Zabin, I., 309, 321.Zablow, L., 232.Zacherl, M. K., 357.Zafiriadis, Z., 171.Zahler, R. E., 128.Zahn, H., 163.Zak, B., 358.Zakharkin, L. I., 247.Zannier, H., 353.Zapp, J. A., 313.Zarinsky, V. A., 359.Zaslowsky, J . A., 171.Zawadzki, J., 76.Zdanuk, E. J., 93.Zechmeister, L., 179, 180.Zeiger, H. J., 12.Zeiss, H. H., 134.Zeldovich, J . , 72.Zelinskaya, N. D., 76Zeller, P. , 181.Zemany, P. D., 61.Zemek, F., 366.Zenitani, B., 335.Zenitz, B. L., 165.Zeppernick, F., 89.Zernike, J., 116.Ziegler, M., 366.Zietlow, J. P., 12.Zill, L. P., 256, 372.Zilliken, F., 264.INDEX OF AUTHORS' NAMES. 40'3Zimm, B. H., 82, 86.Zimmer, E. L., 70.Zimmer, W. F., 128.Zimmerman, H. E., 198.Zimmerman, P. A., 100.Zimmermann, G., 370.Zimmermann, H., 155.Zimmermann, M., 146.Zinke, A., 190.Zinner, H., 372.Ziomek, J . S., 14.Zissis, E., 261.Zobrist, R., 258.Zook, W. C . , 346.Zorina, E. L., 88.Zschaage, W., 99.Zuidema, G. D., 233.Zuur, A. P., 107.Zwanzig, R. W., 81, 82.Zwingelstein, G., 229.Zwolinski, B. J., 47, 48, 66.Zymalkowski, F., 169

ISSN:0365-6217    

DOI:10.1039/AR9535000379

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

INDEX OF SUBJECTS.(" detn." = determination)Abietic acid, structure of, 209.neoAbietic acid, structure of, 209.Absorptiometry, 362.Absorption spectra, use of, in analysis, 368.Acenaphthene, synthesis of, 189.Acetaldehyde, liquid, photo-oxidation of,Acetaldehyde, photolysis of, 44.Acetoacetate, formation of, by enzymes,Acetone, photolysis of, 44.2-a-Acetoxycholest-4-en-3-one, formation2-Acetylchrysene, formation of, 190.Acetylene, band system of, 20.Acetylenes, prototropy in, 176.Acids, weak, titration of, 358.Acid-base catalysis, 142.Acid-catalysed anionotropic rearrange--4crylonitrile, aqueous, kinetics of poly-Actinometry, 43.Acyl-coenzyme A dehydrogenation, 305.Adipic acid, kinetics of polycondensationof, with pentane-1 : 5-diol, 57.Adrenocorticotrophic hormones, 270.Agar, structure of, 327.Agarobiose, structure of, 327.Agrocybin, 177.Alcohols, aliphatic, detection of, 356.Aldehydes, aliphatic, autoxidation of, 147.Aldehydes, photolysis of, 44.Aldehydes, prepartion of, 167, 174.Aldose series, a new method of descent in,Alginic acid, 324.Alicyclic compounds, 201.Aliphatic compounds, 176.Alkali metals, reduction by, 169.Alkaloids, 245.identification of, 356.n-Alkanes, bond dissociation energies in,6-Alkylaminotetrazoles, reactions of, 239.Alkylchlorosilanes, solutions of, in di-9-Alkyldibenzofluorenes, preparation of,Alkylene dihalides, detection of, 356.Ally1 phenyl ethers, rearrangements of,Aluminium, detection of, 345.detn.of, 341, 346, 348, 353, 365, 367.Aluminium borohydride preparation of,storage of, precautions in, 97.47.307.of, 229.ments, 141.merisation of, 60.in radiation chemistry, 63.266.24.methylformamide, 103.189.197.96.Aluminium bromide, hydration and hydro-lysis of, 99.Aluminium bromide and chloride, com-plex salts of, with hydrazine, 99.Aluminium ethylsulphinate, formation of,99.Aluminium hydride, and derivatives of,98, 99.Alums, dehydration of, 73.Ambreinolide, structure of, 209.Amides, N-substituted, vibrations in, 15.Amines, aromatic, deamination of, 199.oxidation of, to nitro-compounds, 199.oxidation of, by aryl iodosoacetates,149.aryl, formation of, 199.primary, detn.of, 358.(f)-Amino-acids, general method of re-Amino-acids, 268.3-Amino-3-deoxy-~-ribose, synthesis of,2-Amino-2-deoxy-~-xylose, synthesis of,Amino-groups, detn.of, 366.threo - 2 -Amino - 1 - p - nitrophenyl-l : &pro-panediol, 162.( +)-2-Amino-l-phenylpropane (benze-drine), use of, in optical resolution ofacids, 158.Amino-sugars, 261.5-Aminotetrazoles, formation of, 238.11-Aminoundecanoic acid, kinetics ofAmmonia, detn. of, 363.solution of, 157.in algae, 330.265.265.polycondensation of, 57.in presence of hydrazine, 352.photolysis of, 43.trideutero-, spectrum of, 11.Ammonium, detn. of, in presence ofAmmonium oxide and hydroxide, solid,Amperometric titrations, 361.u-Amylases, degradation of a-1 : 4-linkagesby, 293.,%Amylases, degradation of u-1 : 4-linkagesby, 290.y-Amylase, 297.Amylo-1 : 6-glucosidase, 299.Amylopectin, structure of, 290.Amylosaccharides, structural analysis of," Amylose isomerase," 299.B-Amyrin, absolute configuration of, 21 1.steroid numbering of, 21 1 .Analysis, gas, 376.radiochemical, 375.potassium, 347.105.by enzymic degradations, 299.41INDEX OF SUBJECTS.41 1Analytical chemistry, 336.Anchiometric assistance, definition of,( f )-epiAndrosterone, total synthesis of,1 : 5-Anhydro-~-gulitol, formation of, 259.Anhydro-sugars, 257.Anionotropic rearrangements, 138.Anodic synthesis of long-chain fatty acids,Anthanthrone, 4 : 10-dibromo-, orient-Anthocyanins, detn. of, 368.Anthracene, photolysis of, 45.Anthraquinone, 1 : 4- and 1 : 5-dimethoxy-,basicity of, 194.Antimony, detn.of, 349, 354.in organic compounds, 358, 366.Arborine, reactions of, 252.Aromatic compounds, 188.bond dissociation energies of, 26.Aromatic substitution, 125.Arsenic, detn. of, 347, 363.Arsenite, detn. of, 352.Arsenic compounds, heats of formation of,Arsenic trifluoride, angle in, 19.cycloArteno1, structure of, 211.Asiatic acid, structure of, 214.Aspartic acid, 278.Associated liquids, 83.Asymmetric enzymic hydrolysis, 157.Asymmetric induction, steric control of,Asymmetric reactions, 162.Atomic processes, 40.A4utoxidation, 147.Axial bond, definition of, 124, 202.Azides, decomposition of, 78.Azirines, formation of, 233.cis-Azobenzene, indi'viduality of, 199.Azodinitriles, kinetics of decomposition of,Azomethane, photolysis of vapour of, 45.cis-2 : 2'- and -3 : 3'-Azopyridines, form-cis-Azoxybenzene, formation and reduc-Azulene, formation of, from cyclodecaneAzulenes, 192.Bacitracin A, 269.Baeyer-Villiger reaction, mechanism of,Barium oxide, red, lattice defects in, 94.Bases, weak, potentiometric titration of,Benzaldehyde, kinetics of photo-oxidationBenzene, molecular dimensions of, 11.oxidation of, by Fenton's reagent, 52.resonance energy of, 33.Benzene-cyclohexane and benzene-rubbersystems, theory of, 85.135.220.preparation of, 258.173.ation of, 195.28, 29.160.39.ation of, 163.tion of, 199.derivatives, 203.properties and reactions of, 193.146.377.of, 46.Benzoic acid, oxidation of, by Fenton'sreagent and by hydrogen peroxide.145.Benzoyl peroxide, homolytic reactions of,146.NN-Benzylideneaniline, acid-catalysedhydrolysis of, 55.N-Benzylidene-a-p-diphenylylbenzyl-amine, isomerisation of opticallyactive, 143.3 - Benzyl- 9 - methyl - 3 : 9 - diazabicyclo -[3 : 3 : llnonane, formation of, 240.Beryllium, detection of, 344.Beryllium acetate, basic, monoclinic,Beryllium borohydride, preparation of, 96.Beryllium oxide, gaseous, dissociationBimolecular nucleophilic displacements,Biochemistry, 281." Biogenetic isoprene rule," 204.Biosynthesis of steroids, 230.Bisethylenediaminedichloroplatinu m ( IV )Bismuth, detection of, 345.Biscyclopentadienyl derivatives ofchromium, cobalt, nickel, rhodium,and iridium, 118.Bistrifluoromethyl-arsinous and -arsinicacid, 114.Boivinose, structure of, 259.Bond energies, 24.Borazens, 97.Borine, co-ordination compounds of, withtrialkylphosphines, etc., 95.Boron, detn. of, 364.in alloys with aluminium, 353.Boron carbides, 97.Boron chlorides, structures of, 98.Boron compounds, heats of formation of,Boron halides, reactions of, with alkylBoron-nitrogen bond moments, 97.Brassidic acid, autoxidation of, 147.2-Bromo- and 2-chloro-cholestan-3-one,configuration of, 217, 218.2-Bromo-4-ethoxycarbonyl-3-methylpyr-role, formylation of, 233, 234.a-Bromo-ketones, configuration of, 21 7.l-Bromo-2-toluene-~-sulphonamidonaph-thalene, halogenation of, 195.Browning in foods, etc., causes of, 264.Butadiene, polymerisation of, in gas phase,cycloButane, mercury-photosensitised re-Butan-1-01, l-deutero-, stereospecific syn-tert.-Butyl hydroperoxide, photochemicaltert.-Butyl hypochloride, oxidation ofdetn. of, 353, 367.formation of, 93.energy of, 29.heat of formation of, 93.131.ion, partial resolution of, 121.detn.of, 349, 366.28, 29.silicates, 98.58.action of, 46.thesis of, 162.decomposition of, 58.alcohols by, 170412 INDEX OEisoButyry1 chloride, reaction of, withmethyl radicals, 42.Cadmium, detection of, 344.Czesium, detn. of, 364.Calamenene, structure of, 207.Calcium, detn. of, 364, 367.Calcium, heat of solution of, in liquidCalcium iodide, heat of solution of, inCalcium oxalate, hygroscopic nature of,Calcium peroxychromate, structure of, 94.Camphenamine, structure of, 205.( +)- and (-)-Camphor-3-carboxylic acid,Cantharidin, synthesis of, 235.Carbohydrates, 2 5 3.detn.of, 341, 348, 353, 359, 360, 364.ammonia, 93.liquid ammonia, 93.348.kinetics of decarboxylation of, 162.detection, estimation, and separation of,detn. of, 367.See also Sugars.253, 255, 356.Carbon, detn. of, in titanium, 364.Carbon, latent heat of sublimation of, 31.Carbon-carbon bonds, dissociation energyCarbon dioxide, fixation of, in aceto-Carbon disulphide, fluorination of, 113.Carbon tetrafluoride, infra-red intensitiesof, 33.acetate, 316.in, 16.thermal decomposition of, 31.Carbon-nitrogen bond, geometrical iso-merism arising from restricted rota-tion about, 163.Carbonyl chloride, complex of, with tri-methylamine, 101.Carbonyl chloride hydride, 117.Carbonyl compounds, detection of, 356.Carbonylation, 17 2.Carboxylic acids, 173.y-Carotene, synthesis of, 179.Carotenoids, 178.Carpaine, structure of, 246.Carragheenin, 327.Caryophyllene (/3-caryophyllene), structure#?-Caryophyllene alcohol, structure of, 207./3- and y-Caryophyllene, nomenclature of,( +)-trans-Caryophyllenic acid, structuret~ans-( f )-Caryophyllenic acid, optical re-Catalysed reactions, use of, in analysis, 377.Catalytic hydrogenation, 166.Catechols, preparation of, 196.Cedrene and cedrol, structure of, 208.Cellulose in algz, 325.Ceric ions, reduction of, by poloniumby y-radiation, 70.Ceric salts, electron-transfer reactions of,detn.of, 358.of, 207, 208.207.of, 208.solution of, 157.a-rays, 64.51.SUBJECTS.Cerium, detn. of, 346, 365.Cerium(II1) cyanamide, preparation of,Chamazulene, structure of, 193.Chemical changes in homogeneous systems,Chemical kinetics] theory of, 35.Chloramine, hydrolysis of, 105.Chlorate, detn. of, in mixtures withChlorates, thermal decomposition of, 78.Chloride, detn. of, 351.Chlorine, detn. of, 363.Chlorine, reaction of, with hydrogen, inpresence of nitrosyl chloride, 43.Chlorine trifluoride, molecular dimensionsof, 11.Chlorite, use of, in volumetric analysis,351.Chloroform, infra-red intensities in, 17.Chlorophyceae, carbohydrates in, 329.Chloroplumbates, 105.Chlorotrifluoromethane, C1-C bond in, 19.Cholesterol, oxidation of, 229.epzcholesterol, hydrogenation of, 229.Cholesteryl acetate, oxidation of, 229.Chromatography, absorption, 371.Chromatography, use of, in separation ofamino-acid mixtures, 278.Chromatography of carbohydrates, 255.Chromic acid, mechanism of oxidation by,151.Chromic chloride, hydrated, exchange ofoxygen between water and, 50.Chromium, detn.of, 365, 367.Chromium trioxide-pyridine complex,use of, in oxidation, 170.Chromyl chloride, mechanism of oxidationby, 152.Cicutoxin, 177.Cinerolone, optical resolution of, 157.Citronellic acid, cyclisation of, 205.Claisen rearrangement, the, 196.Clovene and isoclovene, structure of, 207,Coal tar, distillation products of, 188.polycyclic bases from, 242.Cobalt, detection of, 345.detn.of, 349, 354, 365.Cobalt complexes, 119.Cobaltammines involving fatty acids, 119.&Cobalt octacarbonyl, 11 7.Cobaltic ion, mechanism of catalysis by, 62.Cobaltous chloride, ions formed from, 120.Colorimetry, 362.Complex ions, reactions of, 54.Complexes, metal, stability of, 89.Con ductometric titration, 362.Co-ordination number 5, compounds hav-Copolymerisation, 60.Copper, complex salts of, 92.Copper, detection of, 345.detn. of. 354. 359. 364.100.34.perchlorate, 351.partition, 370.208.ing, 120.Copper, latent- heat of vaporisation of, a t0" K, 92INDEX OF SUBJECTS. 41 3Copper(1) chloride, reaction of, withCopper(1r) pyrophosphates, 92.Copper sulphate pentahydrate, dehydr-Corlumine, synthesis of, 247.Coronene, isolation of, in hydrogenationCorticrocin, synthesis of, 177.Cortisol, formation of, from cortisone,Cortisol acetate (“ hydrocortisone ”), form-Cortisone, conversion of, into cortisol, 226.Cortisone acetate, formation of, from( +)-Cortisone acetate, total synthesis of,Corynantheidine, structure of, 248.Corynomycolenic acid, structure of, 183.Coulometry, 360.Critical phenomena, 87.Crocetin, synthesis of, 181.Cryptoxanthin, structure of, 180.Crystallite theory of liquids, 82.Cyanate, detn.of, 363.Cyanide, detn. of, 364.Cyanogen fluoride, non-formation of, 114.a- and ,3-Cyperone, structure of, 209.Decalin hydroperoxide, thermal decom-n-Decane, autoxidation of, 147.cycZoDecane derivatives, formation ofbicycZo[5 : 3 : O]Dec-1(7)-en-8-one, form-Dehydroergosterol, aromatization of, 228.%Deoxy-~-ribose, formation of, 260.Deoxy-sugars, 259.2-Deoxy-~-xylose, formation of, fromDepolymerisation, 61.Deuterium cyanide, bcnd lengths in, 12.Deuterium iodide, ionic character of, 19.Dextropimaric acid, structure of, 209.Diabetes, effect of, on fatty-acid meta-Diacetyl, formation of, in photolysis ofDiacetyl peroxide, rate of decomposition5 : 5-Dialkylbarbituric acids, dealkylation2 : 2‘-Diaminodifluorenylidene, isolation ofcis-Diazidochromiun~(111) complexes, 11 1.Diazoaminobenzene, transformation of,1 : 1-Dibenzoylethane, reduction of twoDiborane, dissociation of, 94.preparation of, 95, 96.reactions of, 95.vapour hydrolysis of, 94.acetylene, 92.ation of, 74.of coal, 188.226.ation of, 223.formation of, from ergosterol, 224.substance S, 222.219.position of, 57.azulene and naphthalene from, 203.ation of, 203.D-glucose, 260.bolism, 310.acetone, 44.of, 57.of, 240.two forms of, 163.photolysis of vapour of, 44.200.forms of, 167.Dicrotaline, structure of, 250.Diethylaminomagnesium bromide as con-densing agent, 172.“ Dihydrobenzaldehyde,” constitution of,192.Dihydroeudesmol, structure of, 209.Dihydrosphingosine, configuration of, 277.stereochemistry of, 185.a-Di-imines, aliphatic, ferrous iodidecomplexes of, 119.Dimensions, molecular, 9.6-Dimethylamino-4 : 4-diphenylheptan-3-one methiodide, pyrolysis of, 236.Dimethylaniline, complex of, with oxygen,148.reaction of, with benzoyl peroxide, 146.a2-Dimethylbenzoyl hydroperoxide, cat-alysed decomposition of, 144.2 : 2-Dimethyl-3 : 3-diphenylethylene-imine, formation of, 233.1 : 3-DimethylcycZopentanes, configurationof, 164, 202.1 : 2-Diols, kinetics of oxidation of, bylead tetra-acetate, periodic acid, andaryl iodosoacetates, 148.‘ a- and /3-Diphenacyl halides,” structureof, 198.Diphenyls, optically active, in naturalproducts, 158.3 : 8-Diphenylperylene, identity of, 190.Diphtheria bacilli, acids of, 182.4 : 4’- and 5 : 6’-Diquinolyl, enantiomers of,Diterpenes, 2C6.5 : 5’-Dithiazolyl, preparation of, 237.Di-m- and -p-xylylene, distortion of ringsDolomite, thermal decomposition of, 75.Eburicoic acid, structure of, 212.Ecgonine and +-ecgonine, configuration of,Elaidic acid and its esters, autoxidation of,Elbs reaction, the, 198.Electroanalysis, 359.Electron transfer, mechanism of, 48.Electron-transfer reactions, 50.a-Eleostearic acid, 182.Eliminations, bimolecular nucleophilic,carbonyl-forming, 134.Emetine, synthesis of, 247.Enol acetates in steroids, reactions of, 230.Enoyl-coenzyme A hydration, 305.Entropy factor and stability of complexions, 90.P-Enzynes, 297.R-Enzyme, 299.2 : 3-Epoxybutane, absolute configurationof, 153.( -)-1 : 2-Epoxy-3-phenoxypropane, rota-tory dispersion of, 153.Equatorial bond, definition of, 124, 202.Eremophilone, structure of, 204, 209.Ergosterol, conversion of, into cortisone,158.in, 154.165.147.132.224414 INDEX ’ OF SUBJECTS.Erucic acid, synthesis of, 173.Erythrogenic (isanic) acid, 177.Esterification and ester hydrolysis, 143.Esters, phenolic, detection of, 356.Ethyl alcohol, anthraquinone-sensitised1 -deu tero-, stereospecific synthesis of,photo-oxidation of, 46.161.Ethyl bromide, heat of formation of, 27.Ethyl nitrate, photolysis of vapour of, 45.Ethylene, Raman spectrum of, 13.Ethylene, 1 : l-dideutero-, infra-red spec-trum of, 13.Ethylenediaminetetra-acetic acid, uses of,340.Ethylidene dimethacrylate, copolymeris-ation of, with methyl methacrylate, 61.2-Ethylidene-5-methyl-3 : 3-diphenyl-tetrahydrofuran, formation of, 236.Ethylsilanes, decomposition of, 102.Europium, detn.of, 354.Extraction, use of, in analysis, 373.chloride, heat of formation of, 27.Fasting, effect of, on fatty-acid metabolism,Fatty acids, 181.Fatty-acid activation, 303.Febrifugine, synthesis of, 251.ZsoFebrifugine, structure of, 251.Fenton’s reaction, mechanism of, 52.Fenton’s reagent, oxidations by, 145.Ferric chloride, ions formed from, 119.Ferricyanide, alkaline, mechanism ofoxidation by, 152.Ferrocene, spectra of, 13.Ferrocyanide, detn.of, 354.Ferrous hydroxide, oxidation of, 116.Ferrous-ferric system in radiation reac-tions, 68.Ferrous ions, autoxidation of, in aqueoussolution, 51.Ferrous sulphate actinometry, 64.Filicinic acid, synthesis of, 215.Flash photolysis, 22.Flavaspidic acid, structure of, 215.Flaviolin, structure of, 194.Flavones, detn. of, 368.isoFlavones, formation of, 243.Floridean starch in algae, 326.Fluorescence, 47.Fluoride, detn.of, 351, 367.Fluorimetry, 367.Fluorine, detn. of, 363.310.oxidation of, 301.metabolism in animal tissues, 391.synthesis, 308.detn. of, 349, 350.in organic compounds, 358.dissociation energy of, 21, 27.elementary, detn. of, 351. ‘Formaldehyde, quantitative yields of, inoxidations by periodates, 149.Formates, thermal decomposition of, 76.Formic acid and formates, kinetics ofoxidation of, 53.Free-radical processes, 40.Fries rearrangement, the, 198.Fucoidin in algz, 324.Funorin, 329.Gadolinium oxide, purification of, 100.Gallium, detn. of, 348.Gallium(III) chloride, dimeric, 100.Gallium, dialkyl-, complexes of, 100.Gas reactions, first-order and unimolecular,termolecular, 37.Germanium, detection of, 344.detn.of, 347.“ Gluc-amylase,” 296.D-Glucose, conversion of, into 2-deoxy-D-xylose, 260.Glutamic acid, 278.I ‘ L-a-Glycerylphosphorylethanolamine,”preparation of, 184.Glycogen, degradation of, by enzymes, 288.general structure of, 288.Glycols, detection of, 356. ’See also 1 : 2-Diols.Glycosylamines, 261.Glyoxal vapour, photolysis of, 44.GIyoxalines, naturally occurring, 237.Gold, detn. of, 348.Graphite, heat of sublimation of, 101.Gravimetric analysis, inorganic, 345.Hafnium alkoxides, 103.Halogen derivatives, gaseous, gas-gastitration by and of, 376.Halogenation, 127, 171.Halogens, detn.of, in organic compounds,357.Handianol, possible identity of, withcycloartenol, 212.Harman, synthesis of, 241.Heats of reaction, 29.Heliotrinic acid, structure of, 187.Hentriacont-7-en-16-one, synthesis of, 183.12-Heptane, vapour-phase oxidation of,2 : 3-cycZoHeptindole, dehydrogenation of,Heterocyclic compounds, 233.Heterolytic reactions, 125.2 : 3 : 4 : 2‘ : 3‘ : 4‘-Hexamethoxydiphenyl-6 : 6’-dicarboxylic acid, optical purityof, 158.Hexamethyldiplatinum, 123.cycZoHexane derivatives, cis-1 : 3-disub-stituted, configuration of, 164.cycZoHexanes, 1 : 3-disubstituted, stabilityof cis- and trans-, 202.cycZoHexene, per-acid oxidation of, 146.cycZoHexeny1 hydroperoxide, thermal de-9-cycZoHex-l’-enylfluorene, identity of,Hexitols in algae, 326.D-Homosteroids, total synthesis of, 221.Hormones, artificial, 227.Humulene, structure of, 208.Hydrates, decomposition of, 73.38.occurrence of, in algae, 331.147.241.composition of, 57.189INDEX OF SUBJECTS.415Hydrazine, complex salts of, with alum-detection of, 344.NN-dimethyl-, reaction with diborane,electron-transfer reactions of, 51.reaction of, with diborane, 95.reactions of, 105.salts of halogeno-stannates and -stan-Hydrazobenzene, mechanism of dispro-Hydrocarbons, aromatic polynuclear, detn.bond distances and mean bond energiesinium halides, 99.95.nites, 104.portionation of, 200.of, 366.in, 32.“ Hydrocortisone.” See Cortisol acetate.Hydrogen, dissociation energy of, 27.exchange reaction of, with tritium, 65.gaseous, and aqueous potassium hydr-oxide, exchange between, 50.molecular, vibrational transition of, 13.reaction of, with chlorine, in presence ofnitrosyl chloride, 43.Hydrogen bromide, infra-red intensities in,16.Hydrogen chloride, infra-red intensities in,16.Hydrogen cyanide, bond lengths in, 12.Hydrogen peroxide, detn.of, by cericsolutions, 352.mechanism of reactions of, 52.oxidations by, 145.use of, in organic oxidations, 170.Hydrogen sulphide, ionisation of, byHydroxyamino-acids, cis j trans-oxazo-Hydroxyl radical, micro-wave spectrum of,Hydroxylamine, detn. of, 363.Hydroxylamines, aliphatic, autoxidationof, 148.3-Hydroxy-N-methylmorphinan, synthe-sis of, 243.,9-2-Hydroxyphenylacrylic acids, ring-closure of, 188.3/3-Hydroxy-5a-steroids, configuration of,210.( -)-fi-Hydroxytetradecanoic acid, isol-ation and synthesis of, 182.H ypercon j ugation, 129.Hypochlorous acid, reactions of, witharomatic substances, 128.“ Imine,” NH, preparation of, 105.Indicators in volumetric analysis, 355.Indium, detn.of, 367.Indium ions, uni- and bi-valent, 101.Indium sesquioxide, 101.Indole-3-aldehyde and -3-carboxylic acid,Infusible white precipitate, formula of,Inorganic chemistry, 89.Instrumental methods of analysis, 359.Insulin, structure of, 270,bombardment, 63.line interconversion in, 277.11.reduction of, 241.94.Iodine, detn. of, by catalytic effect, 377.in organic compounds, 358.elementary, detn. of, 351.exchange of, between its monochlorideand other halides, 49.solubility of, in aqueous sulphuric acid,115.Iodosoacetates, aryl, kinetics of oxidationby, 148.Iodyl fluoride, 115.Ion exchange, use of, in analysis, 372.Ion-exchange resins as catalysts, 171.use of, in separation of carbohydrates,+-Ionone, cyclisation of, 206.Ionophoretic separation of carbohydrates,Iridium trisacetylacetone complex, 121.Iridophycin, structure of, 328.Iron, dectection of, 345.detn.of, 348, 350, 354, 365, 367.Iron complexes, oxidation of, induced byIsanic acid. See Erythrogenic acid.Isotope effects, 56.Jerusalem artichoke, enzymes of, 282.Kamlolenic acid, structure of, 182.a-Keto-esters, conformation of, 159.Ketogenesis, 3 1 1.Ketolysis, 31 1.Ketones, photolysis of, 44.preparation of, 174.Laevopimaric acid, structure of, 209.Laminarin in algz, 323.Lanosterol, absolute configuration of, 21 1 .Lanthanons, group detection of, 345.Latent heats, 31.Lavandulic and By-dihydrolavandulic acid,cyclisation of, 205.Lead, detection of, 345.Lead metaphosphate, 106.Lead tetra-acetate, kinetics of oxidationof 1 : 2-diols and phenols by, 148.“ Limit dextrinase,” 299.1 : 6-Linkages, degradation of, by hydro-lytic enzymes, 298.Linoleic acid, methyl ester, autoxidationof, 147.Lipids in algae, 331.Liquids and liquid mixtures, theory of, 80.Lithium, detn.of, 348.reduction by, 169.Lithium aluminium hydride, reduction by,Lithium borohydride, preparation of, 96.Lithium fluoroborate, preparation of, 98.Lithium methylamide, 91.Longifolene and its hydrochloride, struc-Lucidin, constitution of, 195.Lumisterol, structure of, 219.Lupanoline, 246.Lupene-I, structure of, 215.256.256.electron transfer, 52.detn.of, 346, 355, 359, 366, 367.167.ture of, 209416 INDEX OF SUBJECTS.Lycorine, structure of, 251.Lysergic acid, isomerisation of, 249.Magnesium, detn. of, 341, 353, 364.Magnesium chloride, basic, 93.Maleic anhydride, addition of, to 9 : 10-diphenylanthracene, 190.Manganate and permanganate ions, rateof electron transfer between, 48.Manganese, detn. of, 348, 354, 365.Manganese dioxide, use of, in oxidations,&Manganese heptoxide, properties of,Manganese ions, valency of, 115.Mannitol in algae, 322.Marine algae, constituents of, 322, 330.Marrubiin, structure of, 210.Meerwein-Pondorf€ reactions, mechanismMercury, detection of, 344.Mercury 6(3P1) atoms, quenching of, byMercury, diethyl-, pyrolysis of, 26.dimethyl-, pyrolysis of, 26.diisopropyl-, pyrolysis of, 26.Metal carbonyls, 116.Metathioboric acid, forms of, 98.Methane, deutero-, dimensions of, 9.trideutero-, dimensions of, 9.Methyl acrylate, aqueous, kinetics ofMethyl alcohol, molecular dimensions of,Methyl borate, reaction of, with sodiumMethyl hyposphosphate, 106.Methyl iodide, photolysis of, 42, 45.Methyl methacrylate, copolymerisation of,kinetics of polymerisation of, 58.Methyl (f )-boxoetianate, total synthesisMethyl radicals, kinetics of gas-phasereaction of, with isobutyryl chloride, 42.trideutero-, reactions of, 41.Methyl vinhaticoate, structure of, 210.N-Methylanilides, use of, in preparation ofaldehydes, 167.4-Methyl- 5 : 6- benzo-l-phenanthrylaceticacid, optical resolution of, 154.Methylcyclohexane, vapour-phase oxid-ation of, 147.( +)-3-Methylcyclohexanone, 2 : 6-dibenz-ylidene, and derivatives, opticalrotation of, 154.N-Methylmorphinan, synthesis of, 242.( -) - 2- (2-Methyl-6-nitropheny1)thiophen-3-carboxylic acid, optical stability of,158.1-Methyl-2-phenylbutyl toluene-$-sul-phonate, solvolysis of, 137.l-Methyl-2-phenylpropyl toluene-p-sul-phonate, acetolysis of, 137.€69, 229.115.of, 150.detn. of, 348, 353, 354, 364.oxygen, 46.bond energies of, 32.polymerisation of, 60.10.hydride, 95.with ethylidene dimethacrylate, 61.of, 221.reactions of, 40.Methylphosphines, mono-, di-, and tri-,Methylpyrenes, formation of, in high-12- and 13-Methyltetradecanoic acids,4-Methylthio-6-oxocanthine, reactions of,Microbiological oxidation, 222, 223, 227.Molecular collision diameters, 11.Molecular-weight distribution in polymers,Molecules, polyatomic, excited states of,Molybdenum, detection of, 345.12-Molybdoceric( IV) acid, proparation andMonocrotaline, structure of, 250.2-Monoglycerides, preparation of, 184.Monoterpenes, 204.Mould invertase, inhibition of, by glucose,Mould invertases, 283.Murexine, structure of, 237.Mycarose, structure of, 261.Mycoceranic and mycocerosic acids,identity and structure of, 183.a-Mycolic acid, structure of, 183.Mycolipenic acid, structure of, 182.Mycomycin, 177.Naphthalene, detn.of, 368.Naphthalene, oxidation of, by Fenton’sreagent and by hydrogen peroxide, 145.Necrosamine, structure of, 185.Nephelometry, 367.Nickel, detection of, 345.detn. of, 349, 354, 365, 367.Nickel-carbon bonds in carbonyls, 11 7.Nickel carbonyl, reaction of, with sulphurNickel carbonyl cyanide, preparation of,Nickel(I1) phenylacetylide, I1 8.Nickel(I1) thiocyanate, ions formed from,Niobium, detn. of, 366.Nitrate, detn. of, 352.Nitration, 126.Nitric acid, exchange of oxygen betweenNitric acid hydrates, infra-red spectra of,Nitric acid vapour, pyrolysis of, 40.Nitric oxide, infra-red intensities in, 16.Nitriles, hydrolysis of, by hydrogen per-Nitrite, detn.of, 352, 363.Nitrites, allryl, formation of, by reaction ofnitrogen dioxide on alcohols, 38.Nitrogen, detn. of, in organic compounds,357.preparation of, 106.pressure petrol synthesis, 188.isolation of, 182.249.62.20.detn. of, 349, 365.properties of, 100.284.synthesis of, 183.nitride, 11 7.117.120.distinction of, from nitrite, 344.water and, 50.13.oxide, 146.distinction of, from nitrate, 344.dissociation energy of, 27IKDEX OF SUBJECTS. 417Nitrogen in aromatic amines, intervalencyNitrogen oxysulphide, a new, 108.diNitrogen pentoxide, kinetics of decom-diNitro en tetroxide, dipole moment of,Nitrogen trichloride, decomposition of, 43.Nitro-group, stretching frequencies in, 14.Nitrocydopropane, properties of, 201.Nitroso-group, effect of, on halogenation,Nitrosyl chloride, oxidation of, by azone,Nitrous oxide, spectra of, 9.cycZoNonane-1 : 5-diols, formation of, 203.Nortropine and nor-#-tropine, configur-Novic acid, structure of, 214.Nucleophilic displacements in aromaticNucleotides, 245.Nucleus formation and growth, 70.trans-Octadec-2-enoic acid, preparation of,Octamethylnaphthalene, 188.cyclooctane-1 : 4-dio1, formation of, 203.bicycZo[3 : 3 : 010ctane-2 : 5-dione, CZS-( +)-Octan-2-01, rotatory dispersion of, 153Whanthotoxin, 177.Oppenauer reactions, mechanism of, 150.Organic analysis, 355.Organic chemistry, 124.Osmium, co-ordination compounds of, 121.Oxalate, detn.of, 366.Oxalates, thermal decomposition of, ‘76.Oxidation of organic compounds, 169.Oxidation mechanisms in organic chemis-Oxindole, reactions of, 242.3-Oxindolylacetic acid, synthesis of, 242.Oxygen, complex of, with dimethylaniline,detn. of, in organic compounds, 357.micro-wave absorption spectrum of, 19.1 l-Oxygenated steroids, formation of, 222.Oxytocin, 268.Ozone, micro-wave spectrum of, 11.oxidation of nitrosyl chloride by, 37.Ozonisation, 147.Ozonolysis, 170.Pachyrrhizon, isolation of, 244.Palladium, cis-complexes of, 121.Palmital-plasmalogen, synthesis of, 184.Penicillin derivatives, synthesis of, 237,Pentacene, synthesis of, 190.angles of, 163.position of, 39.reactions of, 106.101,128.37.thermal decomposition of, 43.thermal decomposition of, 40.ation of, 164.systems, 128.173.non-planarity of, 154.fusion of rings of, 203.detn.of, 349, 350, 366, 377.try, 144.148.in tin, 364.detn. of, 366.238.Pentane-1 : 5-diol, kinetics of polyconden-Peptides, 268.Perchlorates, thermal decomposition of,Perchloric acid hydrates, infra-red spectraPerfluoro-carboxylates, metal, thermalPerhydroanthracenes, internal energy of,Perhydrophenanthrenes, internal energyPeriodic acid, kinetics of oxidation by, 148.Permanganate, oxidations by, mechanismPermanganates, thermal decomposition ofPeroxotungstate ion, 112.Persulphates, mechanism of oxidation by,53.Phaeophycez, carbohydrates of, 322.Phenanthrene, 4 : &dimethyl-, Synthesisof, 189.Phenols, detn.of, 377.kinetics of oxidation of, by lead tetra-acetate, 149.oxidation of, 196.sation of, with adipic acid, 57.78.of, 13.decomposition of, 187.217.of, 217.of, 53, 150.77.Phenyl azide, chain structure of, 200.Phenyl esters, preparation of, 174.Phenyl radicals, formation of, 98.Phenyl toluene-p-sulplionate, hydrolysisPhenylazoxynaphthalenes, 200.a-Phenylethylamine, optical resolution of,2-Phenyl-1 : 3 : 5-triazine, preparation of,Phosphatides, 184.Phosphine, dimethyl-, reaction of, withI’hosphorazo-compounds, use of, in syn-Phosphoric acid, poly-, uses of, 174, 194.Phosphorous acid, complexity of, 106.Phosphorus, brown, 106.Phosphorus, detn.of, 363.Phosphorus compounds, heats of forni-ation of, 28, 19.Phosphorus pentachloride, conductance of,107.Phosphorylases, degradation of a-1 : 4-linkages by, 297.Phosphorylation of enzymes, 271.‘‘ Phosphyls,” 106.Photochemistry, 43.Phthalic acid, oxidation of, by Fenton’sreagent and by hydrogen peroxide,145.C,, Phthienoic acid, identity of, withrnycolipenic acid, 183.Picene, synthesis of, 190.Pigments in algae, 334.Platinum, attack of, by hydrogen chloride,of, 143.158.240.diborane, 95.thesis of peptides, 279.dimer, and its sodium salt, 106.121.detn. of, 350418 INDEX OF SUBJECTS.Platinum-olefin compounds, structure of,Polar bond, definition of, 124, 202.Polarography, 360.Polycyclic aromatic hydrocarbons, 188.Polydimethylsiloxanes, heats of formationPolymer solutions, thermodynamic pro-Polymerisation, ionic, 62.Polymerisation of single monomers, 58.Polypeptide degradation, methods for, 275.Polypeptide end-groups, determination of,Polyporenic acids A, B, and C, structure of,Polysaccharides, 267.Poly-ynes, naturally occurring, 177.Porphobilinogen, structure of, 234.Potassium, detection of, 344.Potassium dioxalatodiaquochromate(m),Potassium ferrioxalate, as actinometricPotassium fluorodisulphate, 109.Potentiometric titrations, 362.Precipitation in homogeneous solution, 346.cycZoPropane, rate of isomerisation of, toPropene, 3 : 3-dichloro-, reaction of, withisopropyl vinyl ether, rate of decompos-Proteins, 268.Protein end-groups, determination of, 272.Proteins in algz, 331.Purine, 9-fl-D-ribofuranoside of, occurrencea-Pyridil, conversion of, into di-2-pyridylPyridine, detn.of, 363, 367.Pyridine N-oxides, use of, 239.a-Pyridoin, structure of, 239.2-Pyridone, electron density in crystals of,Pyrosulphuryl chlorofluoride, 109.Pyrroles, substituted, synthesis of, 233.Quadrupole coupling coefficients, 19.Qualitative analysis, inorganic, 343.Quinoline, 2 : 4-dihydroxy-, structure of,242.4-Quinolone, 2 : 3-dihydroxy-, correctedstructure of, 242.Quinovic acid, structure of, 214.Radiation chemistry, 63.Radium, concentration of, from mixtureswith barium, 346.Raman lines, intensities of, 18.Rates of aquation of certain cobalt com-plexes, 120.Reactions a t solid interfaces, 70.Reactions in solution, 47.Reactions, photo-sensitised, 46.Reactions, very rapid, study of, 34.122.of, 29.perties of, 86.272.212.detn.of, 347, 353, 364.kinetics of formation of, 11 1.substance, 43.propylene, 39.ethoxide ion, 139.ition of, 39.of, in Nature, 244.ketone, 239.239." Reconstructed systems," 307.Reformatsky reaction, the, 172.Regular solutions, definition of, 83.Reserpic acid, structure of, 249.Reserpine, isolation of, 249.Rhenium, detn. of, 365.Rhenium oxide, complexes of, 116.Per-rhenates, reduction of, 116.Rhodium-trisacetylacetone complex, 121.Rhodophyceae, carbohydrates in, 325.Riddellic acid, structure of, 187.Riddelliine, structure of, 251.Ring A in steroid ketones, conformation of,isoRubijervosine, structure of, 252.(&-)-Rubremetinium bromide, synthesis of,Ruthenium, detn.of, 366.Ruthenium(v1) pyrosulphate, 120.Ruthenocene, spectra of, 13.Saccharinic acids, mechanism of formationSalford, air of, polycyclic aromatic hydro-Samarium, metallic, preparation and pro-Sandarakopimaric acid, structure of, 210.+-Santonin, structure of,' 206.Sarsasapogenin, stereochemistry of, 21 8.Scandium, detection of, 345.Scilliglaucosidin, structure of aglycone of,Selenium, detection of, 344.218.247.of, 261.carbons in, 188.perties of, 99.232.detn. of, 347, 352, 364, 367.in organic compounds, 358.tetrafluoride, 110.structure of, 13.Selenium dithiocyanate, formation of, 110.a-Selinene, structure of, 209.Sesqu iterpenes, 20 6.Silica (or silicon), detn.of, 347, 364.Silicon, compounds of, with selenium andtellurium, 101.halides of, 102.organo-derivatives, 102.reactive form of, 101.Silicon alkoxides, 103.Silicon tetrafluoride, infra-red intensitiesin, 16.Siloxenes, 102.Silver, detn. of, 354, 359, 365.Silver complexes with amines, 92, 93.Silver oxide, autocatalytic decompositionSkimmiol, structure of, and identity withSmilagenin, stereochemistry of, 21 8.Sodium, detn. of, 348, 353.Sodium borohydride, properties of, 96.Sodium polysulphides, 110.Sodium trimethoxyborohydride, formationand reactions of, 95.Solvents, function of, in ionic polymeris-ation, 63.non-aqueous, use of, in analysis, 376.of, 74.taraxerol, 214.reduction by, 169INDEX OF SUBJECTS.419Sommelet reaction, mechanism of, 150.cis-trans-Sorbic acid, preparation of, 174.Sorbicillin, synthesis of, 173.L-Sorbose, decomposition of, by hydro-Spectra, flame, 23.molecular, 9.Raman, of trans-uranic oxides, 13.Spectrography, emission, 367.Spectroscopy, far infra-red, 15.Sphingine, synthesis of, 186.Sphingomyelin, structure of, 185.Starch, degradation of, by enzymes, 288.general structure of, 288.Stereochemistry, 152.1 : 8-diamino-4 : 5-dimethylphenazone,1 : 2-dichloropropane, 153.(+)-9 : l0-dihydro-3 : 4-5 : 6-dibenzo-phenanthrene, 156.9 : 10-dihydro-4 : B-dimethylphenan-threne, 156.6 : 6’-di- and 5 : 5’ : 6 : 6’-tetra-iododi-phenyl-3 : 3’-dicarboxylic acid, 159.steroids, 216.Steroids, 216.infra-red intensities in, 17.As : 7-Steroids, synthesis of, 169.Sterols in algae, 332.Styrene, copolymerisation of, with sulphurdioxide, 61.kinetics of polymerisation of, 58.Substitutions, bimolecular nucleophilic,Sucrose, chemical synthesis of, 258.Sugar nitrates, preparation of, 266.Sugars, branched-chain, 259.See also Carbohydrates.Sulphate, detn.of, 352.Sulphide, detn. of, 366.Sulphur, allotropy of, 108.detn. of, 364, 367.exchange of, 49.green and purple, 107.bond force constant in, 20.chloric acid, 259.micro-wave and infra-red, comparisonof results of, 9.154.131.in organic compounds, 358.Sulphur dioxide, copolymerisation of, withSulphur hexafluoride, infra-red intensitiesSulphur hydronitride, 108.Sulphur monoxide dimer, structure of,Sulphur trioxide-methanesulphonic acidSulphuric acid as an ionising solvent, 110.Sulphurimide, 108.Synartetic acceleration, definition of, 136.Tantalum, detn.of, 366.Taraxastene, structure of, 215.Taraxerol, structure of, and identity withskimmiol, 214.styrene, 61.in, 16.second-order transition in, 87.108.system, 109.as a primary standard, 350.(+)-Tartramidic acid hydrazide, use of, inoptical resolution of carbonyl com-pounds, 158.Tartrazine, destruction of, effect of doserate on, 69.Tellurium, detection of, 344.in organic compounds, 358.detn. of, 347, 364.Tellurium dichloride, 110.diTellurium decafluoride, 11 1.Terpenes, 204.Terramycin, structure of, 200.“ Testololactone,” formation of, 224.Testosterone, preparation of, from andro-stenedione, 229.2 : 3 : 4 : 6-Tetra-O-acetyl-~-glucose, useof, in optical resolution of amines, 158.1 : 2 : 3 : 9-Tetra-azaphenanthrene 3-oxide,formation of, 242.Tetra-O-benzoyl-/hbfructopyranosyl bro-mide, reduction of, 168.Tetra-0-methyl-a-D-glucose, mutarotationof, 142.Tetramethylplatinum, 123.Tetraphenylchromium halides, 11 1.Tetracyclosqualene, structure of, 214.Thalictricavine, structure of, 246.Thallium detection of, 345.Thallous sulphide, oxidation of, 101.Thermochemistry, 24.2-Thiazolylmagnesium bromide, syntheticuse of, 237.Thienopyridines, 236.Thioamides, structure of, 14.Thiocyanate, detn.of, 364.Thionyl chloride, Raman spectrum of,“ Thiophen sulphone,” structure of, 236.Thiophthen, solid, formation of, 236.Thiosulphate, detn.of, 360.Thiosulphate ion, structure of, 110.Thiotrithiazyl ion, 109.Thorium, detn. of, 341, 346, 349, 354, 366.Thorium hypophosphate, 104.“ Time reactions,” use of, in analysis, 377.Tin, detection of, 345.detn. of, 365.13.detn. of, 349, 354, 359, 366, 36i.dimethyltin salts, 103, 194.Titanium, detection of, 345, 366.Titanium alkoxides, 103.Titanium(rI1) chloride as standard solu-Titrimetric analysis, inorganic, 350.Toluene, gas-phase bromination of, 45.thermal and photochemical brominationTransfructosylation, 281.significance of, 286.Transglycosylation (transglycosidation),Trans-uranic elements, 112.oxides, Raman spectra of, 13.4 : 11 : 12-Tribromofluoranthene, orient-Trichloromethyl radicals, rates of additiontion, 350.of, 25.262, 281.ation of, 190.of, 42420 INDEX OF SUBJECTS.Trifluoroacetyl hypofluorite, preparationTrifluoroiodomethane, reactions of, 114.Trifluoromethyl iodide, photolysis of, 45.Trifluoromethyl radical, addition of, toolefins, 187.Trifluoromethylphosphines, 1 14.2 : 3 : 3'-Trimethoxy-6-styryl-6'-vinyldi-phenyl, optically active, 158.Trimethylene sulphide, planar structure of,233.Trimethylgallium, co-ordination com-pounds of, 100.4 : 5 : 8-Trimethyl-l-phenanthrylaceticacid, optical resolution of, 154.Trimethylplatinum iodide, formation of,123.( f ) - 3 : 13 : 19-Trimethyltricosanoic acid,synthesis of, 173.2 : 4 : 6-Trinitrobenzoic acid as a primarystandard, 351.Triphenylboron-sodium, 98.Tris-1 : l0-phenanthrolinonickel salts, op-tically active, racemisation of, 54.Tristrifluoromethylarsine, 1 14.Trisulphuryl oxfluoride, 109.Triterpenes, steroid numbering of, 211.Tritium, exchange reaction of, withTritium oxide, triple-point temperature of,Tropine and $-tropine, configuration of,Tropolones, 192.Tubercle bacilli, acids of, 182.Tungsten, detection of, 345, 366.Umbellulone dibromide, structure of, 205.Unimolecular anionic rearrangements, 139.of, 113.hydrogen, 65.107.165.Unimolecular nucleophilic displacements,134.Uranium, 112.detection of, 345.detn.of, 360, 366, 367.Uranium hexafluoride, properties of, 112.Usaramoensinecic acid, structure of, 186.Valeroidine, constitution of, 166.Vanadium, detn. of, 355, 366.Vanillin, oxidation of, 198.Vasopressin, 268.Veracevine, structure of, 253.Vibrations, molecular, 12.Vicine, structure of, 240.Vinyl chloride, copolymerisation of, withvinylidene chloride, 60.Vinylene carbonate, formation of, 233.Vinylidene chloride, copolymerisation of,with vinyl chloride, 60.Vinylcyclopropane derivatives, synthesisVitamins in algae, 332, 333, 334.Wagner rearrangement, the, 135.Wool wax, a-glycols in, 182.Yeast I ' debranching " enzymes, 299.Yeast invertase, 284.Yields in radiation reactions, 67.Ytterbium, metallic, preparation of, 99." Zethrene," synthesis of, 191.Zinc, detection of, 344.detn. of, 341, 348, 353, 360, 364, 367.Zinc carbonate, thermal decomposition of,Zirconium, detn. of, 349, 354, 366.Zirconium alkoxides, 103.of, 201.76

ISSN:0365-6217    

DOI:10.1039/AR9535000410

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

PRINCIPAL REFERENCES USED I NCHEMICAL SOCIETY PUBLICATIONPRINCIPAL REFERENCES USED INCHEMICAL SOCIETY PUBLICATIONS.(The titles of some of the Journals listed have undergone several minor changes duringthe past few years ; these are not noted where they do not cause a change in theabbreviated title.)Abbreviated Title..4ct. sci. ind. .Acta Brev. Neer. Physiol. .Acta Chem. Phys. .Acta Chem. Scand. .Acta Chim. Belg. .Acta Cryst. .Acta Med. Scand. .Acta Ophthal., Kbh. .Acta path. nzicrobiol. Scand. .Acta Physicochim. U.R.S.S.Acta Phytochim., Tokyo .Adv. Carbohydrate Chem. .Adv. Catalysis .Adu. Colloid Chem. .Adv. Enzymology .Adv. Protein Chenz. .dgric. Chem. .Anzer. Chem. J . .Amer. Inst. Min. Met. Eng. .Amer. J . Bot. .Anter. J .Digest. Dis. .Amer. J . Med. Sea. .Amer. J . Pharm. .Amer. J . Physiol. .Amer. J . Publ. Health .Ainer. J . Roentgenol. .Amer. J . Sci. .Amer. Math. Soc., Coll. Pub. .Amer. Min. .Anais Assoc. Quim. B r a d .Anal. Asoc. Quim. ArgentinaAnal. Fis. Qudm. .Analyst .Analyt. Chem. .Analyt. Chim. Acta .Anat. Rec. .Angew. Chem. .Ann. Acad. Sci. Fenn..Ann. Biochem. Ex?. Med. .Ann. Bot. .Ann. Chim. .Ann. Chim. analyt. .Ann. Chim. appl. .Ann. Chim. Phys. .Ann. Ferment. .Ann. Inst. Pasteur .Ann. Intern. Med. .Ann. pharm. Franc. .Ann. Physik .FULL TITLE.Actualit& scientifiques et industrielles.Acta Brevia Neerlandica de Physiologia, Pharmacologia,Microbiologia. e-a.Acta Chemica et Physica.Acta Chemica Scandinavica.Acta Chimica Belgica.Acta Crystallographica.Acta Medica Scandinavica.Acta Ophthalmologica Kjsbenhavn.Acta pathologica et microbiologica Scandinavica.Acta Physicochimica U.R.S.S.Acta Phytochimica, Tokyo.Advances in Carbohydrate Chemistry.Advances in Catalysis.Advances in Colloid Chemistry.Advances in Enzymology.Advances in Protein Chemistry.Agricultural Chemicals.American Chemical Journal.American Institute of Mining and Metallurgical EngineersAmerican Journal of Botany.American Journal of Digestive Diseases.American Journal of Medical Sciences.American Journal of Pharmacy.American Journal of Physiology.American Journal of Public Health and the Nation’sThe American Journal of Roentgenology and RadiumAmerican Journal of Science.American Mathematical Society, Collective Publications.American Mineralogist.Anais da AssociacZo Quimica do Brasil.Anales de las Asociaci6n Quimica Argentina.Anales de la Sociedad Espaiiola Fisica y Quimica.The Analyst.Analytical Chemistry.Analytica Chimica Acta.Anatomical Record.Angewandte Chemie (formerly 2.angew. Chem.).Annales Academiae Scientiarium Fennicae (SuomalaisenAnnals of Biochemistry and Experimental Medicine.Annals of Botany.Annales de Chimie.Annales de Chimie analytique et de Chimie appliquCe.Annali di Chimica applicata.Annales de Chimie et de Physique (now divided : seeAnnales des Fermentations.Annales de 1’Institut Pasteur.Annals of Internal Medicine.Annales Pharmaceutiques Franqaises.Annalen $er Physik.Publication.Health.Therapy.Tiedeakatemian Toimituksia) .Ann. Chim.and Ann. Physique).42PRINCIPAL REFERENCES USED. 424Abbreviated Title.Ann. Physique .Ann. Reports .Ann. Rev. Biochem. .Ann. Sci. .A n n . Sect. Anal. phys. chim.A n n . SOC. sci. Brux. .Annalen .Arch. Biochem. .Arch. Biochem. Biophys. .Arch. Eisenhuttenw. .Arch. exp. Path. Pharmak. .Arch. klin. Chir..4rch. Mikrobiol.Arch. Phnrm. ..4rch. Sci. phys. nat. .Arch. Zool.Arkiv Kemi, Min., Geol. .Atti R. Accad. Lincei .APoth.-Ztg. .Arch. S C ~ . b i d . (U.R.S.S.) .A t t i R. Accad. Sci. Torino .Austral. J . Exp. Biol. .A rth. norske Vidensk .-Akad.Oslo, Mat.-nat. Kl. .Bey. .Ber. deut. bot. Ges. .Ber. deut.keram. Ges. .Biochem. J . .Biochem. SOC. Symp. .Biochem. Z. .Biochim.Biochim. Biophys. ActaBiokhim. .Biol. Reviews .B i d . Zentr. .Boll. Chim.-farm. .Boll. SOC. ital. Biol. sperim.Bot. Gaz. .Brit. Abs. .Brit. Dental J . .Brit. J . Exp. Path. .Brit. J . Ophthalmol. .Brit. J . Pharmacol. .Brit. J . Radiol. .Brit. J . Urol. .Bvit. Med. J . .BzcZ2. Acad. polonaise .Bull. Acad. roy. Belg. .Bull. Acad. Sci. Roumaine .Bull. Acad. Sci. U.R.S.S. .Bull. Amer. Ceram. SOC. .Bull. Amer. Phys. SOG. .Bull. analyt. .Bull. Biol. Med. exp. U.R.S.S.Bull. Chem. Soc. Japan .Bull. Chim. SOC. Rornline ..FULL TITLE.Annales de Physique.Annual Reports on the Progress of Chemistry.Annual Review of Biochemistry.Annals of Science.Annales du Secteur d’ Analyse physicochimique, Institutde Chimie gCnCrale (U.R.S.S.).Annales de la SociCt6 scientifique de Bruxelles.Liebigs Annalen der Chemie.Deutsche Apotheker-Zeitung.Archives of Biochemistry.Archives of Biochemistry and Biophysics.Archiv fur das Eisenhuttenwesen.Archiv fur experimentelle Pathologie und Pharma-Archiv fur klinische Chirurgie.-4rchiv fur Mikrobiologie.Archiv der Pharmazie.Archives des Sciences biologiques (U.R.S.S.).Archives des Sciences physiques et naturelles.Archives de Zoologie expgrimentale e t gh6rale.Arkiv for Kemi, Mineralogi och Geologi.Atti (Rendiconti) della Reale Accademia Nazionaledei Lincei.Classe di scienze fisiche, matematichee naturali, Roma.Atti della Reale Accademia della Scienze di Torino.Australian Journal of Experimental Biology andMedicine.Avhandlinger utgitt av det Norske Videnskaps- Akademii Oslo, Matematisk-naturvidenskapelig Klasse.Berichte der deutschen chemischen Gesellschaft.Berichte der deutschen botanischen Gesellschaft.Berichte der deutschen Keramischen Gesellschaft.The Biochemical Journal.Biochemical Society Symposia.Biochemische Zeitschrift.Biochimica.Biochimica et Biophysica Acta.Biokhimiya.Biological Reviews.Biologisches Zentralblatt.Bolletino Chimico-farmaceutico.Bolletino della Societa italiana di Biologia sperimentalla.Botanical Gazette.British Abstracts.British Dental Journal.British Journal of Experimental Pathology.British Journal of Ophthalomology.British Journal of Pharmacology and Chemotherapy.British Journal of Radiology.British Journal of Urology.The British Medical Journal.Bulletin internationale de I’AcadCmie polonaise desSciences e t des Lettres.Bulletin de 1’AcadCmie royale de Belgique.Classe desSciences.Bulletin de la Section Scientifique de 1’AcadCmieRoumaine.Bulletin de 1’AcadCmie des Sciences de 1’U.R.S.S.Bulletin of the American Ceramic Society.Bulletin of the American Physical Society.Bulletin Analytique.Bulletin de Biologie et MCdicine experimentale deBulletin of the Chemical Society of Japan.Bulletinul de Chimie piira si aplicata a1 Societatiikologie.1’U.R.S.S.Romlne de ChimiePRINCIPAL REFERENCES USED. 425Abbreviated Title.Bull. Ex$. Biol. Med. .Bull.Hlth. Org. .Bull. Hyg. .Bull. Imp. Inst. .Bull. Inst. Man. Met. .Bull. Inst. Phys. Chem. Res.,Bull. Johns Hopkins Hosp. .Bull. SOC. chim. . .Bull. SOC. cham. Belg. .Bull. SOC. chim., Belgrade .Bull. Soc. Chim. biol. .Bull. SOC. x i . Bretagne .Bur. Stand. J . Res. .Tokyo .Canad. J . Chern.Canad. J . Res. .Cnnad. Med. Assoc. J . .Cellulosechem. .Cereal Chem. .Chem. Abs.Chem. Analyst .Chem. and I n d . .Chem. Bey.Chem. Fabr. .Chena. Obzor .Chena. Reviews .Chem. Zentr. .Chsmie .Chim. e l’lnd. .China. et I n d . .ChimiaChinese J . PhysilsCold Sflying Harbor Symp.Coll. Czech. Chena. Comm.Colloid J., U.S.S.R. .Compt. rend. .Co,mpt. rend. Acad. Sci.Conzpt. rend. SOC. Biol. .Compt. rend. Trnv.Lab.Contr. Boyce Thom$son Inst.Current Sci. .Dansk Tidsskr . Farm.Deuf. nzed. Woch. .Die Chemie .Discuss. Faraday SOC.U.R.S.S.CarlsbergE. African Med. J . .Edin. Med. J . .Elektrotech. Z. .Eng. M i n . J . .Ergebn. Enzyvnforsch. .Ergebn. exakt. Naturwiss. .Ergebn. Physiol.Ergebn. Vitamin-u. Hovmon-forsch. .Experientia .Fed. Proc. .Finska Kem. Medd.FULL TITLE.Bulletin of Experimental and Biological Medicine.Bulletin of the Health Organisation of the League ofBulletin of Hygiene.Bulletin of the Imperial Institute, London.Bulletin of the Institution of Mining and Metallurgy.Bulletin of the Institute of Physical and ChemicalBulletin of the Johns Hopkins Hospital.Bulletin de la SociCtC chimique de France.Bulletin de la SociCtd chimique de Belgique.Bulletin de la Soci&t6 chimique, Belgrade.Bulletin de la SociCt6 de chimie biologique.Bulletin de la SociCtC scientifique de Bretagne.Bureau of Standards Journal of Research (now J .Res.Canadian Journal of Chemistry.Canadian Journal of Research.Canadian Medical Association JournalCellulosechemie.Cereal Chemistry.Chemical Abstracts.Chemist Analyst.Chemistry and Industry.Chemische Berichte (superseded Ber.) .Die Chemische Fabrilc.Chemickq Obzor.Chemical Reviews.Chemisches Zentralblatt.Chemie.La Chimica e 1’Industria.Chimie et Industrie.Chimia .Chinese Journal of Physics.Cold Spring Harbor Symposium on Quantitative Biology.Collection of Czechoslovak Chemical Communications.Colloid Journal, U.S.S.R.Comptes rendus hebdomadaires des SCances deComptes rendus de l’AcadCmie des Sciences de U.R.S.S.Comptes rendus hebdomadaires de Seances de laComptes rendus des Travaux du Laboratoire Carls-Contributions from the Boyce Thompson Institute.Current Science.Dansk Tidsskrift for Farmaci.Deutsche medizinische Wochenschrift.Nations.Research, Tokyo.Nat. Bur.Stand.).1’AcadCmie des Sciences.SociCtC de Biologie.berg.Die Chemie.Discussions of the Faraday Society (first published1947 ; before that Faradiy Societ? discussions werepublished as part of Trans. Faraday SOC.).East African Medical Journal.Edinburgh Medical Journal.Elektrotechnische Zeitschrift.Engineering and Mining Journal.Ergebnisse der Enzymforschung.Ergebnisse der exakte Naturwissenscliaften.Ergebnisse der Physiologie.Ergebnisse der Vitamin- und Hormonforschung.Experientia.Federation Proceedings.Finska Kemistamfundets Meddelanden (SoumenKemistiseuran Tiedonantoja)426 PRINCIPAL REFERENCES USED.Abbreviated Title.GazzettaGeneesk. Tijdscir.Nederl.:Geol. Mag.Helv. Chim. Acta .Helv. Phys. Acta .Helv. Physiol. Pharmacol. ActaI n d . Chem. Chem. M a n u f . .I n d . chim. belg. .I n d . Eng. Chem.I n d . Eng. Chem. Anal. .Indian J . Med. Res. .Indian J . Physics .Ing.-chim. .Inorg. Synth. .Inst. int. Chim. Solvay .Iowa State Coll. J . Sci. .J . Agric. Chem. Soc. Japan .J . Agric. Res. .J . Agric. Sci. .J . Amer. Ceramic SOC.J . Amer. Chem. Soc..J . Amer. Med. Assoc. .J . Amer. Oil Chem. SOC. .J . Amer. Pharm. Assoc. .J . Ap#. Chern. .J . Appl. Chem., U.S.S.R. .J . Appl. Physics, U.S.S.R. .J . Assoc. Off. Agric. Chem. .J . Bact. .J . Biochem., Japan .J . Biol. Chem. .J . Biol. Chem., Sci. Proc. .J . Cell. Comp. Physiol. .J . Chem. Educ. .J . Chem. Phys. .J . Chem. Soc. Japan .J . Chim. phys. .J . Chjnese Chem. SOC. .J . Clzn. Invest. .J . Coun. Sci. Ind. Rzs.,Australia .J . Econ. Entomol. .J . Electrochem. Assoc. JapanJ . Electrochem. SOC. .Indie .J - *J . Endocrinol. .J . Exp. Biol. .J . Ex$. Med. .J . Franklin Inst.J . Gen. Chem., U.S.S.R.J . Gen. Physiol. .J . Geol. .J - HYg. - J . Immunol.J . I n d . Eng. Chem. .J . I n d . Hyg. .FULL TITLE.Gazzetta chimica italiana.Geneeskundig Tijdschrift voor Nederlandsch-Indie.Geological Magazine.Helvetica Chimica Acta.Helvetica Physica Acta.Helvetica Physiologica et Pharmacologica Acta.Industrial Chemist and Chemical Manufacturer.Industrie chimique belge.Industrial and Engineering Chemistry (formerly J .I n n .Industrial and Engineering Chemistry : AnalyticalIndian Journal of Medical Research.Indian Journal of Physics.Ingknieur-chimiste.Inorganic Syntheses.Institut international de Chimie Solvay. Conseil deIowa State College Journal of Science.Journal of the Chemical Society.Journal of the Agricultural Chemical Society of Japan.Journal of Agricultural Research.Journal of Agricultural Science.Journal of the American Ceramic Society.Journal of the American Chemical Society.Journal of the American Medical Association.Journal of the American Oil Chemists’ Society.Journal of the American Pharmaceutical Association.Journal of Applied Chemistry (London).Journal of Applied Chemistry, U.S.S.R.Journal of Applied Physics, U.S.S.R.Journal of the Association of Official AgriculturalJournal of Bacteriology.Journal of Biochemistry, Japan.Journal of Biological Chemistry.Scientific Proceedings of the American Society ofJournal of Cellular and Comparative Physiology.Journal of Chemical Education.Journal of Chemical Physics.Journal of the Chemical Society of Japan.Journal de Chimie physique.Journal of the Chinese Chemical Society.Journal of Clinical Investigation.Journal of the Council for Scientific and IndustrialJournal of Economic Entomology.Journal of the Electrochemical Association of Japan.Journal of the Electrochemical Society (commencedpublication 1948, 93 : volume numbering the same asTrans. Electrochem.Soc.).Journal of Endocrinology.Journal of Experimental Biology.Journal of Experimental Medicine.Journal of the Franklin Institute.Journal of General Chemistry, U.S.S.R. (formerlyJournal of General Physiology.Journal of Geology.Journal of Hygiene.Journal of Immunology.Journal of Industrial and Engineering Chemistry (nowI n d . Eng. Chem.).Journal of Industrial Hygiene and Toxicology.Eng. Chem.).Edition (now Analyt. Chem.).Chimi e.Chemists.Biological Chemists (bound with J .Biol. Chem.).Research, Australia.chemical part of J . Russ. Phys. Chem. SOC.)PRINCIPAL REFERENCES USED. 427Abbreviated Title.J . Indian Chem. SOC. .J . Indian Inst. Sci. .J . Infect. Dis. .J . Inst. Brew. .J . Inst. Elect. Eng. .J . Inst. Metals .J . Inst. Petrol. .J . Int. SOC. Leath. Chem.J . Iron Steel Inst. .J . Lab. Clin. Med. .J . Marine Biol. Assoc.J . Marins Res. .T . Nutrit. .J . Oil Colour Chem. ASSOG. .J . Org. Chem. .J . Pediat. .J . Pharm. Belg. .J . Pharm. Chim.J . Pharm. Pharmacol.J . Pharm. SOC. Japan .J. Pharmacol. .J . Phys. Chem. .J . Phys. Chem., U.S.S.R. .J . Phys. Colloid Chern. .J . Phys. Radium .J . Phys., U.S.S.R. .J . Physiol.J . Polymer Sci. .J .pr. Chern. .J . Proc. Austral. Chem. Inst.J . Proc. Roy. Sac. N.S.W. .J . Res. Nat. Bur. Stand. .J . Roy. Inst. Chem. .J . Roy. Microscop. SOC. .J . Rubber Res. .J . Rtdss. Phys. Cham. SOC. .J . Sci. Food Agric. .J . Sci. Ind. Res., IndiaJ . S G ~ . Instr.J . Soc. Chem. Ind.J . Soc. Chem. Ind., Japan .J . Soc. Dyers and Col.J . Text. Inst. .Kgl. Danske Vidinskab:Selsk. .Kgl. fysiogr. Sallsk. LundForh .Kgl. Norske Vidensk. ' Selsk.Forh.Kgl. Norsde Vidensk. ' Selsk.Skrifter ,Kolloid-Beih. .Kolloid Z.Lancet .Makromol. Chem. .Mem. Coll. Agric. Kyoto .Mem. Coll. Sci. Kyoto ..FULL TITLE.Quarterly Journal of the Indian Chemical Society.Journal of the Indian Institute of Science.Journal of Infectious Diseases.Journal of the Institute of Brewing.Journal of the Institutiw of Electrical Engineers.Journal of the Institute of Metals.Journal of the Institute of Petroleum.Journal of the International Society of Leather TradesJournal of the Iron and Steel Institute.Journal of Laboratory and Clinical Medicine.Journal of the Marine Biological Association of the U.K.Journal of Marine Research.Journal of Nutrition.Journal of the Oil and Colour Chemists' Association.The Journal of Organic Chemistry.Journal of Pediatrics.Journal Pharmacie de Belgique.Journal de Pharmacie et de Chimie.Journal of Pharmacy and Pharmacology.Journal of the Pharmaceutical Society of Japan.Journal of Pharmacology and Experimental Thsra-Journal of Physical Chemistry.Journal of Physical Chemistry, U.S.S.R.Journal of Physical and Colloidal Chemistry (formerlyJournal de Physique et le Radium.Journal of Physics, U.S.S.K.Journal of Physiology.Journal of Polymer Science.Journal fur praktische Chemie.Journal and Proceedings of the Australian ChemicalJournal and Proceedings of the Royal Society of NewJournal of Research of the National Bureau of StandardsJournal of the Royal Institute of Chemistry.Journal of the Royal Microscopical Society.Journal of Rubber Research.Journal of the Russian Physical and Chemical SocietyJournal of the Science of Food and Agriculture.Journal of Scientific and Industrial Research, India.Journal of Scientific Instruments.Journal of the Society of Chemical Industry.Journal of the Society of Chemical Industry, Japan.Journal of the Society of Dyers and Colourists.Journal of the Textile Institute.Kongelige Danske Videnskabernes Selskab, Mathe-matisk-fysiske Meddelelser.Kongliga fysiografiska Sallskapets i Lund Forhandlinger.Kongelige Norske Videnskaber Selskabs Forhandlinger.Kongelige Norske Videnskaber Selskabs Skrif ter.Kooloid-Beihefte.Kolloid Zeitschrift.Lancet .Die Makromolekulare Chemie.Memoirs of the College of Agriculture, Kyoto ImperialMemoirs of the College of Science, Kyoto ImperialChemists.peutics.J .Phys. Chem.).Institute.South Wales.(formerly Bur. Stand. J . Res.).(now obsolete : cf. J . Gen. Chem., U.S.S.R.).Universj ty.University428 PRINCIPAL REFERENCES USED.Abbreviated Title.Mem.Inst. Chem. Ukrain.Meun. Manchester Lit. Phil.Mem. R. Accad. Ital. .Acad. Sci.SOC.Metal Ind.Metallforsch. .Metallw .Mikrochein. .Mikrochem. Mikrochim. ActaMikrochim. Acta. .Min. Mag.. .Monatsh. .Nach. Ges. Wiss. GottingenNaturwiss.Nederl. Tijds. Natuurk.Neues Jahrb. Min. .New England J . Med.New Phytol. .Nord. med. Tidsskr. .Nuovo Cim. .Nutrit. Ahs. Rev.Oesterr. Chem.-Ztg. .Org. Synth. .Paint Oil Chem. Rev. .Pjliig. Arch. ges. Physiol.Pharm. Acta Helv. .Pharm. J . .Pharm. Weekblad .*Pharnz. Zentralh.Pharm. Ztg. .PharntaziePhil. Mag.Phil. Trans. .Physica .Phys. Review .Physikal. Z. .Physikal. Z . SovietunionPhysiol. Reviews .Plant Ph ysiol.Pogg. Ann.Post Grad. Med. J.Poultry Sci..Proc. Acad. Nat. Sci. .Proc. Amer. Acad. Arts Sci.PYOC. Camb. Phil. Soc. .Proc. Chem. Soc..Proc. Geol. ASSOG. .PYOG. Imp. Acad., Tokyo .PYOG. Indian Acad. Sci. .Proc. Indiana Acad. Sci. .Proc. K. Ned. Akad. Wet. .Proc. London Math. SOC. .Proc. Mayo Clin. .Proc. Nat. Acad. Sci. .PYOG. Nat. Inst. Sci. India .FULL TITLE.Memoirs of the Institute of Chemistry, UkrainianMemoirs and Proceedings of the Manchester Literary andMemoire della Reale Accademia d’Italia. Classe diMetal Industry.Metallforschung.Metallwirtschaft, Metallwissenschaft, Metalltechnik.Mikrochemie.Mikrochemie vereinigt mit Mikrochimica Acta.Mikrochimica Acta.Mineralogical Magazine and Journal of the MineralogicalMonatshefte fur Chemie und verwandte Teile andererNachrichten von der Gesellschaft der WissenschaftenNaturwissenschaften.Nederlandsch Tijdschrift voor Natuurkunde.Neues Jahrbuch fur Mineralogie, Kristallographie undPetrographie.New England Journal of Medicine.New Phytologist.Nordisk medicinisk Tidsskrift.Nuovo Cimento.Nutrition Abstracts and Reviews.Oesterreichische Chemiker-Zeitung.Organic Syntheses.Paint, Oil and Chemical Review.Pfliigers Archiv fur die gesamte Physiologie desPharmaceutica Acta Helvetiae.Pharmaceutical Journal.Pharmaceutisch Weekblad.Pharmazeutische Zentralhalle fur Deutschland.Pharmazeutische Zeitung.Pharmazie.Philosophical Magazine (The London, Edinburgh andDublin).Philosophical Transactions of the Royal Society.Physica.Physical Review.Physikalische Zeitschrift.Physikalische Zeitschrift der Sowjetunion.Physiological Reviews.Plant Physiology.Poggendorfs Annalen (now Annalen).Post Graduate Medical Journal.Poultry Science.Proceedings of the Academy of Natural Sciences ofPhiladelphia.Proceedings of the American Academy of Arts andSciences.Proceedings of the Cambridge Philosophical Society.Proceedings of the Chemical Society (ceased in 1914).Proceedings of the Geologists’ Association.Proceedings of the Imperial Academy, Tokyo.Proceedings of the Indian Academy of Science.Proceedings of the Indiana Academy of Science.Proceedings of the Koninklyke Nederlandsche AkademieProceedings of the London Mathematical Society.Proceedings of the Staff Meetings of the Mayo Clinic.Proceedings of the National Academy of Sciences.Proceedings of the National Institute of Science of India.Academy of Sciences.Philosophical Society.Scienze fisiche, matematiche e naturali.Society.Wissenschaf ten.zu Gottingen.Menschen und der Tiere.van WetenschappenPRINCIPAL REFERENCES USED.429Abbreviated Title.Proc. Phys. Soc.Proc. Roy. Irish Acad.. .Proc. Roy. Soc. .Proc. Roy. SOC. Edinburgh .Proc. Roy. SOC. Medicine .Proc. SOC. Exp. Biol. N . Y . .Publ. Amer. Assoc. Adv. Sci.Publ. Hlth. Rep., Wash. .Quart. J . Exp. Physiol. .Quart. J . Geol. SOG. .Quart. J . Pharm.@art. Reviews .Radiology .Rec. Trav. chim.Re$. Brit. Assoc. .Research .Rev. Brasil. Chim. .Rev. Fac. Sci. Istanbul .Rev.Imnnmnol. .Rev. I n d . nain. .Rev. Mod. PhysicsRev. sci. .Rev. Sci. Inslv. .Ric. sci. .Roczn. Chem. .S. African J . Sci.Schweiz. mad. Woch.Sci. J . Roy. Coll. Sci.Sci. Papers Inst. Phys. Chem.Res., TokyoSci. Proc. R. Dublin Soc. .Sci. Progress .Sci. Rep., Tohoku .Sitzungsber. A kad. Wiss.W i e nSitzungsber. Ges. Beford.Naturwiss. MarburgSkand. Arch. Physiol. .Smithson. Misc. Coll. .Soc. Sci. Fcnn. Phys. Math.Spectrochint. Acta .Slh. Med. J .Suddeut. Apoth.-Ztg.Suomen Kern. .Svensk Kern. Tidskr. .Symp. Soc. Ex?. Biol.Tidsskr. Kjemi .Trans. Amer. SOC. Metals .Trans. Electrochem. SOC. .Trans. Faraday Soc. ,Trans. Illinois Acad. Sci. .Trans. Inst. Chem. Eng. .Trans. N.Y. Acad. Sci. .Trans.Roy. SOC. Canada .Trans. Rov. SOC. Trob. Med.HYg- - Trans. State Inst. Appl. Chem.U.S.S.R.FULL TITLE.Proceedings of the Physical Society of London.Proceedings of the Royal Irish Academy.Proceedings of the Royal Society.Proceedings of the Royal Society of Edinburgh.Proceedings of the Royal Society of Medicine.Proceedings of the Society for Experimental BioIogy andPublications of the American Association for thePublic Health Reports, Washington.Quarterly Journal of Experimental Physiology.Quarterly Journal of the Geological Society of London.Quarterly Journal of Pharmacy and Pharmacology.Quarterly Reviews of the Chemical Society.Radiology.Recueil des Travaux chimiques des Pays-Bas et de laBelgiqu e .Reports of the British Association for the Advancementof Science.Research.Revista Brasileira de Chimica.Revue de la FacultC des Science de l’Universit6 d’Istan-Revue d’Immunologie.Revue de 1’Industrie minerale.Reviews of Modern Pliysics.Revue scientifique, Paris.Review of .Scientific Instruments.Ricerca scientifica.Roczniki Chemii.South African Journal of Science.Schweizerische medizinische Wochenschrift.The Scientific Journal of the Royal College ofScientific Papers of the Institute of Physical aridScientific Proceedings of the Royal Dublin Society.Science Progress.Science Reports, Tohoku Imperial University.Sitzungsberichte der Akademie der Wissenschaften inSitzungsberichte der Gesellschaft zur BeforderungSkandinavisches Archiv fiir Physiologie.Smithsonian Miscellaneous Collection.Societas Scientiarum Fennica, Commentationes Physico-Spectrochimica Acta.Southern Medical Journal.Suddeutsche Apotheker-Zeitung.Suomen Kemistilehti (formerly also known as A ctnSvensk Kemisk Tidskrift.Symposia of the Society of Experimental Biology.Tidsskrift for Kjemi og Bergvesen.Transactions of the American Society of Metals.Transactions of the Electrochemical Society.Transactions of the Faraday Society.Transactions of the Illinois Academy of Science.Transactions of the Institution of Chemical Engineers.Transactions of the New York Academy of Sciences.Transactions of the Royal Society of Canada.Transactions of the Royal Society of Tropical MedicineTransactions of the State Institute of Applied Chemistry,Medicine, New York.Advancement of Science.bul.Science.Chemical Research, Tokyo.Wien.der gesamten Naturwissenschaften zu Marburg.Mathematicae.Chemica Fennica) .and Hygiene.U.S.S.R430 PRINCIPAL REFERENCES USED.Abbreviated Title.Trans.Wisconsin Acad. Sci.Ukrain. Biochem. J . .Ukrain. Chem. J . .U.S. Bur. M i n . .Usp. Chim. .Wied. Ann. .2. anal. Chem. .Z . angew. Chent.Z. angew. Man. .2. angew. Phys. .2. anorg. Chem. .2. Biol.2. Elektrochem. 1Z . Elektrotech. .Z. ges. exp. Med. .2. Krist. .Z. Metallk.Z. Naturjorsch. .Z. physikal. Chem. .2. physikal. chem. Unterricht2. physiol. Chem. .2. tech. Physik .Z . Unters. Lebensm. .2. Vitaminforsch. .Z . Wirts. Zuckerind. .z. Physik .Z. wiss. Phot. .Zavod. Lab. .Zentr. Bakt. .Zentr. Man. .FULL TITLE.Transactions of the Wisconsin Academy of Sciences,Ukrainian Biochemical Jonrnal.Ukrainian Chemical Journal.United States Bureau of hlines (Bulletins, TechnicalUspechi Chimii.Wiedemanns Annalen der Physik.Zeitschrift fur analytische Chemie.Zeitschrift fur angewandte Chemie (now Angezu. Chem.).Zeitschrift fur angewandte Mineralogie.Zeitschrift fur angewandte Physik.Zeitschrift fur anorganische und allgemeine Chemie.Zeitschrift fur Biologie.Zeitschrift fur Elektrochemie (und angewandte physi-kalische Chemie).Zeitschrift fur Elektrotechnik.Zeitschrift fur die gesammte experimentelle Medizinzugleich Fortsetzung der Zeitschrift fur experimentellePathologie und Therapie.Zeitschrift fur KristaIlographie.Zeitschrift fur Metallkunde.Zeitschrift fur Naturforschung.Zeitschrift fur Physik.Zeitschrift fur physikalische Chemie, Stochiometrie undZeitschrift fur den physikalischen and chemischenHoppe-Seylers Zeitschrift fur physiologische Chemie.Zeitschrift fur technischen Physik.Zeitschrift fur Untersuchung der Lebensmittel.Zeitschrift fur Vitaminforschung.Zeitschrift der Wirtschaftsgruppe Zuckerindustrie(Verein der Deutschen Zucker Industrie).Zeitschrift fur wissenschaftliche Photographie, Photo-phvsik und Photochemie.Zavodskaja Laboratorij a.Zentralblatt fur Bakteriologie, Parasitenkunde undInfektionskrankheiten.Zentralblatt fur Mineralogie, Geologie and Palaontologie.Arts and Letters.Papers and Reports of Investigation).Verwandtschaftslehre.Unterricht

ISSN:0365-6217    

DOI:10.1039/AR9535000421

出版商:RSC    

年代:1953

数据来源: RSC