摘要:

Chemistry ofSynthetic DrugsFIFTH EDITIONP. MAY, D.Sc., F.R.I.C., C.P.A., andMALCOM DYSON, M.A., D.Sc., Ph.D., F.R.I.C.The fifth edition of this work has entailed complete rewritingof all sections. The enormous growth of the subject since thepublication of the fourth edition in 1939 has made the sub-division into chapters according to chemical classificationunworkable. The authors have, therefore, redistributed thematerial according to the biological activity of the drugs ex-cept for a part of the field of chemotherapy where the re-tention of special sections devoted to the consideration ofdyestuffs, sulphonamides, the organo-metallic compoundsand antibiotics assists in clarifying the subject matter.It has been kept in mind that the purpose of this volumeis primarily to discuss the chemistry of synthetic drugs ratherthan their application; hence, discussion of pharmacology islimited to those concepts necessary to account the existenceof the chemical substance as a drug or to facilitate discussionof the relation between structure and activity, which must, inturn, act at least as a guide in the synthesis of new drugs.Ready Autumn 1958 Probably E7 10s.Elementary PracticalOrganic ChemistryCOMPLETE EDITIONA.I. VOGEL, D.Sc.(Lond.), D.I.C., F.R.I.C.This volume is a complete text-book of elementary practicalorganic chemistry. For convenience, it is divided into threeparts: Part I. Small Scale Preparations; Part 11. Qualita-tive Organic Analysis; and Part 111. Quantitative OrganicAnalysis. Part I covers a wide range of preparations, manyof which are new, and utilises commercially-available smallscale apparatus designed by the author. Part I1 is a detailedtreatment of qualitative organic analysis, and contains 43comprehensive tables.Part 111 is an authoritative treatmentof elementary quantitative organic analysis, based largelyon functional groups ; it includes many semimicro determina-tions and also titrations in non-aqueous solvents. 45s.Also available in partsPart I. Small Scale Preparations. 21s.Part IT. Qualitative Organic Analysis. 21s.Part 111. Quantitative Organic Analysis. 21s.L O N G M A N SiORGANIC CIIEMICALS BISQLACETATESMethylEthyllsopropylButylAmy1CyclohexylamineACETIC ACIDA.R.and B.P. GradeGlacial 99/ 100%Glacial commercial80% Pure80% Technical981 100%ACETICANHYDRIDEACETI N SMonacetinDiaceti nTriacetinACETOACET-ARYLAM I DESAcetoacetanilideAcetoacet-o-chlorani I ideAcetoacet-o-toluidideAcetoacet-m-Qxylid id eACETONEALCOHOLSButylAmy1Diacetone2-Ethyl bexylPentanol-2ALCOHOLDEN AT U RA NTSo f Wood Naphtha typeCrotonaldehydeALDEHYDESAcetaldehydeAldolButyraldehydeCrotonaldehydeMetalde hydeParaldehydeC ITRATESTributylTriamylDI ETHY LAM I N 0-ETHANOLDIMETHYLACETALHEXYLENEGLYCOLISOPHORONEISOPROPYLMY RISTATELACTATESButylAmy1MESITYL OXIDEMETHYLACETOAC ETATEMETHYL ETHYLKETONEOLEATESEthyllsopropylButylOXALATESDiethylDibutylPHTHALATESDimethylDimethyl glycolDiethylDibutylDiamylBisoflex 81Bisoflex 88Bisoflex 91Bisoflex 79 ISEBACATESBisoflex DBSBisoflex DESBisoflex DNSBisoflex DOSBisoflex 79sSPECIALSOLVENTSFor essences:DIOLANEFor lacquers:DILUOLLOBOSOLSFor textile stiffening:SOLTEXSTEARATESButylAmy1TARTRATESDiethylDibutylTHE DISTILLERS COMPANY LIMITEDChemical Division, Bisol Sales OfficeDEVONSHIRE HOUSE, MAYFAIR PLACE, PICCADILLY, LONDON, W.IPHONE: MAYfair 8867 TELEGRAMS & CABLES: BISOLV LONDON TELEXThe Chemical Industry during the NineteenthCenturyA Study of the Economic Aspect of Applied Chemistryin Europe and North AmericaL. F. HABER‘Well arranged, lucidly written, and abundantly documented, it is boundto be widely used as an authoritative reference book.. . . This is a bookthat can be warmly recommended to chemist, economist and historianalike, and indeed to everybody interested in the beginnings of what hasbecome one of the key industries of the world.’ TREVOR I. WILLIAMS inTHE NEW SCIENTIST 45s. netA Modem Approach to Organic ChemistryJ. PACKER AND J. VAUGHANWith a Forewurd by c. K. I N G 0 L DA book which covers basic requirements for an initial degree. Whereverdesirable and possible, presentation of factual material is accompanied bya treatment of the relevant theory. Text-figures 84s. netElectronic Theories of Organic ChemistryAn Introductory TreatmentJOHN WILLIAM BAKERThis is a non-mathematical, introductory approach to the application ofthe electronic theory of valency to structure and mechanism in organicchemistry. It is intended primarily for advanced sixth form and first yearuniversity students.Text-figures 30s. netAn Introduction to Chemical ThermodynamicsE. F. CALDINAn introduction for university students. Full use is made of actual experi-mental results, and there are many applications to topics of currentchemical interest. References are given to selected reviews and originalpapers. Text-figures 50s. net.MONOGRAPHS O N THE PHYSICS AND CHEMISTRY OF MATERIALSTheory of DielectricsDielectric Constant and Dielectric LossH. FROHLICHSecond edition 30s. netOXFORD UNIVERSITY PRESSxItems from our 1958 Catalogue-have you had your copy?Z y m o s a n 68/- G Tris - (hydroxy - methyl) - amino methane 12/- HS a k u r a n i n 14/- d Pyridine-2-aldoxime methiodide 80/- HOpianic acid 39/- D Propionyl-thiocholine chloride 9/- GT e t r o p h a n e 35/- D L-Glutamic acid decarboxylase 3901- GBatyl alcohol 32/- D M e t h y l p e n t a d e c y l k e t o n e 52/- H8 - T h u j a p l i c i n 27/- G 4 - M e t h y l - 2 - p i c o l y l a m i n e 107/- Ht r a n s - S t i l b e n e 36/- H 2 - H y d r o x y - d i b e n z o f u r a n 18/- DM e t h a l l y l a m i n e 48/- H Pyromellitic dianhydride 58/- HS e l a c h y l a l c o h o l 180/- H 2-Picolyl-chloride H C l 82/- HP l a s m o c o r i n t h B 28/- D DL-Leucyl-DL-leucine 65/- G5 - B e n z y l o x y i n d o l e 481- G 2-Ethyl cyclohexanol-1 lo/- HisoButeny1 b r o m i d e 39/- D a-Naphthacetonitrile 58/- HB u f o t e n i n , b i o x a l a t e 48/- d Hexachloropropylene 25/- H“Triglycine sulphate” 135/- H y-Methyl-glutamate 17/- Dl - M e t h o x y b u t e n - 1 - y n - 3 12/- H 4-isoPropyl-phenol 96/- KL - A r g i n i n e - L - g l u t a m a t e 33/- D Triphenyl phosphine 135/- KSodium phytate (anhydrous) 40/- H a, a‘ a“-Tripyridyl 22/- d2, 2, 3, 3-Tetrafluoro-l-propanol 39/- D S - N a p h t h o i n 16/- GPyridine-2-carbinol-6-carboxylic acid Q u a t e r r y 1 e n 120/- d 30/- DL.LIGHT & Co. Ltd. Poyle, Colnbrook, Bucks, EnglandSCIENTIFIC & TECHNICAL BOOKSLARGE STOCK OF BOOKS on the Biological, Physical,Chemical and Medical Sciences supplied from stock, or obtained to order.FOREIGN DEPARTMENT.Books not in stock obtained toorder with the least possible delay.LENDING LIBRARYSCIENTIFIC AND TECHNICALAnnual Subscription from LI 17s. 6d.THE LIBRARY CATALOGUE, revised to December, 1956, con-taining a classified Index of Authors and Subjects, to Subscribers,LEI 5s. net; to Non-Subscribers, f.2 2s. net ; postage 2s.Prospectus post free on application.Bi-monthly list of New Books and New Editions added to the Library,sent post free to any address regularly.LONDON: H. K. LEWIS & CO. Ltd.I36 GOWER STREET, W.C. I TELEPHONE: EUSTON 4282xiAnnual Reportson the Progressof ChemistryBack Numbers (less certainvolumes now out of print)are available-Volumes I (1904) to LIII (1956)AlsoCollective Index of VolumesI to XLVIPrice E l 10s. per volumeInquiries are invited by:THECHEMICALSOCIETYBurlington House - London, W.1xvA Treatise on the Internal Mechanicsof Ball, Tube and Rod Millsby H. E. ROSE and R. M. E. SULLIVANEx. Cr. 8vo. IllustratedChemical Engineering OperationsAn introduction to the Study of Chemical Plantby F. RUMFORD, Ph.D., BSc., M.1.Chem.E.Demy 8vo. 376 pages IllustratedChemical Engineering Materialsby F. RUMFORD, Ph.D., B.Sc., M.1.Chem.E.Demy 8vo. 350 pagesElectrostatic Precipitation in Theoryand Practiceb.v H. E. ROSE and A. J. WOODEx. Cr. 8vo. IllustratedFrom the DOVER List of Paper-back Reprints:Physical Principles of the Quantum Theoryby W. HEISENBERG184 pagesAtomic Spectra and Atomic StructureBy G . HERZBERG251 pagesThe Kinetic Theory of LiquidsBy J. FRENKEL488 pages25s.32s. 6d.32s. 6d.17s. 6d.10s.16s.20s.Complete catalogue available on request toCONSTABLE & CO. LTD.10 ORANGE STREET, LONDON, W.C.

ISSN:0365-6217    

DOI:10.1039/AR95754FP001

出版商:RSC    

年代:1957

数据来源: RSC

摘要:

ANNUAL REPORTSON THEPROGRESS OF CHEMISTRYGENERAL AND PHYSICAL CHEMISTRY.RADIO-FREQUENCY SPECTROSCOPY.ABOUT five hundred papers of chemical interest have appeared on this topicsince the last Report 1 on it in 1955. Nuclear magnetic resonance (NMR,NSR) is the most active field, closely followed by electron (paramagnetic)resonance (EPR, EMR, or ESR). Both methods are being applied to almostany system which will give spectra. They can deal with a wide variety ofmaterials, and are often powerful in revealing special phenomena related tostructure. Microwave spectroscopy of gases remains unrivalled for its powerto yield structural detail about simple polar molecules, and continues to beso applied to diverse suitable substances. Nuclear quadrupole resonance(NQR) has developed more slowly, but is being used to study the interactionsof an increasing variety of quadrupole nuclei with their environments.Microwave Spectroscopy.-Development of technique has continued onestablished lines.Gordy and his collaborators have extended the high-frequency limit of the radio-frequency range to over 500,000 Mc./sec., awavelength of under 0.6 min., and have measured spectra there. They alsodescribe a high-temperature molecular beam spectrometer in which ro-tational transitions are measured for K+Cl- and Na+Cl- at 3 mm. wave-lengths. A spectrometer of exceptional sensitivity (minimum absorptioncoefficient 5 x cm.-l) has been described4 for wavelengths near 3 cm.Very accurate measurements of dipole moments have been made in aninstrument in which a Stark-effect field of great precision is applied. Designshave been given for non-metallic absorption cells suitable for work withfree radicals.The rotation spectrum of HI has been measured,2 the first such work ona diatomic hydride containing the ordinary hydrogen isotope.of the rotation spectrum of ND, is notable, since the immense amount ofThe studyJ .13. Callomon, D. M. Simpson, and N. Sheppard, Awn. Reports, 1955, 52, 81.M. Cowan and W. Gordy, Phys. Rev., 1956,104, 551.A. K. Garrison and W. Gordy, ibid., 1957, 108, 899.H. G. Fitzky, R. Honerjager, and W. Wilke, 2. Physik, 1957, 149, 471.S. A. Marshall and J. Weber, Phys. Rev., 1957, 105, 1502; Rev. Sci. Instr., 1957,E. B. Brackett, P. H. Kasai, and R.J . Myers, ibid., p. 699; C. C. Costain, Canad.G. Erlandsson and W. Gordy, Phys., Rev., 1957, 106, 513.28, 134.J . Phys., 1957, 35, 2418 GENERAL AND PHYSICAL CHEMISTRY.microwave work on NH, has been confined to its inversion spectrum. Thespectrum of ND, shows interesting inversion-doubling.Several asymmetric-top structures have been fully determined.Hydrogen selenide * has d(Se-H) = 1.460 j= 0.013 k and L HSeH =91.0" -J= 0.6"; the dipole moment is 0.24 & 0.02 D. Nitrogen dioxide hasd ( N - 0 ) = 1-197 A and LON0 = 134" 15'. Bromine trifluoridelo has theplanar distorted-T configuration, with d(F-Br) = 1.810 A twice sym-metrically, the unique d(F'Br) = 1.721 A and LFBrF' = 86' 13'. Sul-phuryl fluoride l1 has d(S-0) = 1.405 & 0.003 k, d(S-F) = 1.530 -+ 0.003 k,LOSO = 123" 58' & 12', and LFSF = 96" 7' & 10'; the dipole moment is1.110 & 0-015 n.In SiH,F, the Si-F length l2 of 1.577 0.001 k is inter-mediate between the lengths found in SiH,F and SiF,H; other parametersare d(Si-H) = 1.47 5 0.01 A, LFSiF = 107" 56' &- 6', and LHSiH =112" 1' & 30'; the dipole moment is 1-54 & 0.02 D. A notably thoroughstudy of formamide l3 yields a planar structure with d(C-0) = 1.243 3118" 59' & 30', LNCO = 123" 35' 5 21', and LNCH == 103" 54' & 1.2";the dipole moment of 3.714 -+ 0.06 D makes an angle of 39.6" with the C-Nbond; the quadrupole coupling constants for 14N are 1.9 Mc./sec., 1.7 Mc./sec.,and -3.6 Mc./sec. with reference to the A , B, and C axes respectively.Another outstanding case is that of thiophen l4 for which enough spectrahave now been measured for all eight structural parameters to be determined.For a variety of other molecules, including several cyclic compounds, fewerdata have been published, but significant advances have been made towardsfull structure determinations.Molecules with restricted internal rotation continue to be the subject ofvery important contributions , particularly from Wilson and his school.Barrier heights for many such cases are determinable from the splittingsdue to the tunnelling of hydrogen atoms through the barrier.In a summaryof many of the data,l5 Wilson concludes that the barrier heights are decidedto a considerable extent by the electronic structure of the bond about whichtorsion occurs.Some studies have been combined with particularly elegantstructure determinations, including the establishment of the relative equi-librium positions of the rotating groups. Thus for acetaldehyde l 6 d(C-H)-(methyl) = 1-09 A, d(C-H)(aldehyde) = 1-11 A, LHCH = 108.3", d(C-C) =1-501 A, d(C-0) = 1.216 k, LCCH = 117-5", and LCCO = 124"; a tequilibrium configuration the aldehyde oxygen eclipses one of the methylhydrogen atoms; the barrier height is 1150 & 50 cal./mole and the dipolemoment 2.69 D at an angle of 18" 52' with the A-axis. Methylsilane l7 has0.007 A, d(C-N) = 1.343 & 0.007 A, d(N-H) = 0.995 & 0.007 A, LHNH =8 A. W. Jache, P. W. Moser, and W. Gordy, J . Chem. Phys., 1956, 25, 209.G.R. Bird, ibid., p. 1040.l o D. W. Magnuson, ibid., 1957, 27, 223.l1 D. R. Lide, D. E. Mann, and R. M. Fristrom, ibid., 1957, 28, 734.l2 V. W. Laurie, ibid., p. 1359.l3 R. J. Kurland and E. B. Wilson, jun., ibid., 1957, 27, 585.l4 13. Bak, D. Christensen, J. Rastrup-Andersen, and E. Tannenbaum, ibid., 1956,1 5 E. B. Wilson, jun., Proc. Nat. Acad. Sci. U.S.A., 1957, 43. 816.l6 R. W. Kilb, C . C. Lin, and E. B. Wilson, jun., J . Chem. Plzys., 1957, 26, 1695.1 7 R. W. Kilb and L. Pierce, ibid., 1957, 27, 108.25, 892SHERIDAN : RADIO-FREQUENCY SPECTROSCOPY. 9the expected staggered configuration, with a barrier height of 1700 & 100cal./mole; among the full set of determined parameters is a particularlyprecise length for the Si-C bond length, 1.8668 & 0.0005 A.Methylamine l8has a barrier height of 1980 cal./mole; the dipole moment of 1.326 & 0.015 Dmakes an angle of 76" 40' with the A-axis; the quadrupole couplingconstants for 14N are 2.35 Mc./sec., 2.12 Mc./sec., and -4.47 Mc./sec. withreference to the A , B, and C axes respectively.The theory of the internal rotation problem has been developed con-siderably,l6> l99 2O and in particular tables of Mathieu integrals and othernumerical quantities involved in the computations have been madeavailable.21Several studies concern primarily the effects of quadrupole coupling.Thus the coupling constant for the deuteron 22 along the O-D bond in D,Ois 353 & 4 kc./sec., and the coupling of l70 in HD170 has been used 23 toevaluate the quadrupole moment of that oxygen isotope. From thisknowledge of the nuclear moment and the quadrupole coupling constant of1 7 0 in C170, it is found that the electronic structure of carbon monoxidemust differ in an important way from the conventional concept of thebonding.Electron Resonance.-Electron resonance due to simple ions in crystals,and effects essentially related to crystal structure and nuclear properties,have recently been reviewed.25 McConnell 26 has reviewed the more chemicalaspects of electron-spin resonance (and nuclear magnetic resonance) up toDecember, 1956.A commercial electron-spin resonance spectrometer is now offered 27which uses 3 cm.radiation and has high sensitivity, sufficient to detectabout Details havebeen given 28 of an instrument employing 1.25 cm. radiation which is aboutas sensitive at room temperature with wide-band detection, but which shoulddetect much less than 10-l1 mole of electron spins at low temperatures withnarrowed band-width.A further instrument has also been fully described.29Some of the simplest stable paramagnetic substances to be studied arechlorine dioxide and the alkali super oxide^.^^ In each case the unpairedelectron is shown to be associated with the bonding orbitals, as previouslybelieved.mole of electron spins with a narrow resonance.l 8 D. R. Lide, J . Chem. Pliys., 1957, 26, 343; D. Kivelson and D. R. Lide, ibid.,2o J. D. Swalen, ibid., 1956, 24, 1072.21 D. R. Herschbach, ibid., 1957, 27, 975.22 D.W. Posener, Austral. J . Phys., 1957, 10, 276.23 M. J. Stevenson and C. H. Townes, Phys. Rev., 1957, lG7, 635.24 B. Rosenblum and A. H. Nethercot, J . Chem. Phys.. 1957, 27, 828.25 K. D. Bowers and J. Owen, Re$. Progr. Plays., 1955, 18, 304; D. M. S. Bagguley26 H. M. McConnell, Ann. Rev. Phys. Chem., 1957, 8, 105.27 Varian Associates, Palo Alto, California.2 8 A. A. Buckmaster and H. E. D. Scovil, Canad. J . Phys., 1966, 34, 711.29 M. W. P. Strandberg, M. Tinkham, I. H. Solt, jun., and C. F. David, jun., Rev.50 J . E. Bennett, D. J . E. Ingram, and D. Schonland, Proc. Phys. Scc., 1956, 69,p. 353; T. Nishikawa, J . Phys. SOC. Japan, 1957, 12, 668.K. T. Hecht and D. M. Dennison, J . Chem. Phys., 1957, 26, 31, 48.and J. Owen, ibid., 1957, 20, 304.Sci.Instv., 1956, 27, 596.A , 55610 GENERAL AND PHYSICAL CHEMISTRY.Many electron-spin resonance studies concern bonding in transition-metalcomplexes. The anisotropic g-factor in copper acetylacetone 31 does notagree with the simple Pauling treatment of the bonds, but is more compatiblewith a molecular-orbital approach. For Cu(NH,),SO4,H2O two independentstudies 32 have been differently interpreted regarding the covalent characterof the Cu-N bonds. Some of the most interesting work deals with extensiveapproximately planar arrangements about a paramagnetic atom. In acidmethzemoglobin 33 the g-factor is strikingly anisotropic, being 2-00 & 0.01 inthe haem plane and 6.00 & 0.05 in an axis perpendicular to it. Informationon the bonding of the iron atom and on the crystal structure are bothobtainable.Different results with haemoglobin azide and hydroxide 34 arein accord with the greater degree of covalency ascribed to the iron in suchmaterials. In the azide the g-factor perpendicular to the hzm plane is 2.80,and that in the plane varies from 1.72 to 2.22; a theoretical treatment ofthe bonding has been given.35 Resonance in copper porphin derivatives hasalso been studied,36 and the splitting which appears when chlorine is attachedto the edge of the planar sheet is taken to indicate that the unpaired electronorbital extends across some 9 A similar long-rangeeffect is found in the dibenzenechromium cation,37 where fine structure dueto the coupling of the electron spin with all twelve protons is observed.Relatively stable free radicals of known structure are much studied ;electron-spin resonance of radicals has been reviewed.38 Several papersconcern radicals containing nitrogen, such as derivatives of (C,H,),N anddiphenylpicrylhydrazyl.Line-widths for a series of such radicals have beencorrelated 39 with Hammett’s sigma functions of substituents and discussedin terms of delocalization of electrons. Proton fine structures have beenmeasured in diradicals such as those in which two triphenylmethyl structuresare joined, through their benzene rings, by a saturated chain; 40 spin-exchange in such cases has been studied 41 by the introduction of carbon-13.Semiquinone structures, for example the 1 : 4-naphthasemiquinonecontinue to receive at tention, and molecular-orbital theory has been ap-plied43 to account for the proton fine structures observed.The seventeenelectron-spin resonance peaks of the naphthalene negative ion have alsobeen interpretedu in terms of the spin-densities at the protons; the extrato the chlorine nuclei.31 B. R. McGarvey, J . Phys. Chem., 1956, 60, 71.32 E. H. Carlson and R. D. Spence, J . Chem. Phys., 1956, 24, 471; H. Abe ands3 J. E. Bennett, J. F. Gibson, and D. J. E. Ingram, Proc. Roy. Soc., 1957, A , 240,34 J . F. Gibson and D. J. E. Ingram, Nature, 1957, 180, 29.35 J. S. Griffith, ibid., p. 30.36 D. J. E. Ingram, J . E. Bennett, P. George, and J . M. Goldstein, J . Amer. Chem.37 R. D. Feltham, P. Sogo, and M. Calvin, J .Chem. Phys., 1957, 26, 1354.S. I. Weissman, T. R. Tuttle, jun., and E. de Boer, J . Phys. Chem., 1957, 61, 28.39 R. I. Walter, R. S. Codrington, A. F. d’-4damo, jun., and H. C. Torrey, J . Chem.40 H. S. Jarrett, G. J. Sloan, and W. R. Vaughan, ibid., p. 697.41 D. C. Reitz and S. I. Weissman, ibid., 1957, 27, 968.4 2 J . E. Wertz and J. L. Vivo, ibid., 1956, 24, 479.4s R. Bersohn, ibid., p. 1066; H. M. McConnell, ibid., p. 632.44 T. R. Tuttle, R. L. Ward, and S. I. Weissman, ibid., 1956, 25, 189.K. Ono, J . Phys. SOC. Japan, 1956, 11, 947.67; J. S. Griffith, ibid., 1956, A , 235, 23.SOC., 1956, 78, 3545.Phys., 1956, 25, 319SEERIDAN : RADIO-FREQUENCY SPECTROSCOPY. 11splitting when carbon-13 is at the a-position is discussed45 in terms of theoccurrence of the unpaired electron in both o and x orbitals.Less completetreatments of the negative ions of anthracene and diphenyl 46 accord withthese ideas. A highly symmetrical radical, formed on removal of a hydrogenatom from perinaphthene,*’ is identified from proton splitting in its electronresonance spectrum. The theory of hyperfine interactions in aromatic radicalshas been developed,48 particularly in terms of spin-densities, and it has beenemphasised49 that these densities can be negative, the polarisation at apoint sometimes being opposite to the total spin polarisation of the molecule.The resonance of the naphthalene negative ion is broadened 50 by theaddition of naphthalene, owing to electron exchange between C1,H8- andCl0H8.From this effect rate constants have been evaluated for the exchangeprocess in the presence of various cations and solvents.Liquid sulphur is a complex dynamic system of free radicals, with para-magnetism increasing reversibly as the temperature is raised.51 A thoroughstudy by electron-spin resonance confirms the existing statistical theory ofthe radicals present. Other one-element systems rich in free radicals arethe carbons, on which work has continued 52 in efforts to understand morefully these complex structures.Much research concerns unstable or unidentified radicals, since electron-spin resonance is powerful in detecting traces of paramagnetic species. Insome, but by no means all, such cases, evidence of identity of the species isobtainable.Wide use is made of proton fine-structure for identification.Thus X-irradiation 53 of solid dimethylmercury yields probably C2H,+, andof diethylmercury, C2H, ; dimethylzinc appears to give CH,. and ZnCH,+.Methanol and acetamide, so irradiated,5* probably produce CH2+ and,analogously, C2H,+ is reported from ethanol and from propionamide.Radicals formed by oxidation of diarylamines 55 show nuclear fine structuresin their electron-spin resonance spectra, and are probably important inconnexion with their antioxidant and polymerization-inhibiting properties.Several aromatic substances yield free radicals when dissolved in con-centrated sulphuric acid, When aryl sulphides are so dissolved, the radicalshave been assigned structures 56 from proton splittings.The radicals soformed from fused-ring hydrocarbons have electron-spin resonance spectra 57resembling those of the corresponding negative ions, and it is thought thatthe solutions contain analogous positive ions.Attempts have been made to study simple free radicals, normally formed45 T. R. Tuttle and S. I. Weissman, J . Chem. Plzys., 1956, 25, 189.46 E. de Boer, ibid., p. 190.4 7 P. B. Sogo, M. Nakazaki, and M. Calvin, ibid.. 1957, 26, 1343.4 8 H. M. RlcConnell, ibid., 1956, 24, 764; S. I. Weissman, ibid., 1956, 25, 890.4 9 H. M. McConnell and D. B. Chesnut, ibid., 1957, 27, 984.50 R. L. Ward and S. I. Weissman, J . Amer. Chem SOC., 1957, 79, 2086.D. M. Gardner and G. K. Fraenkel, ibid., 1956, 78, 3279.52 D. E. G. Austen and D.J. E. Ingram, Chem. afzd Ind., 1956, 981; N. S.53 W. Gordy and C. G. McCormick, J . Amer. Chem. SOC., 1956, 78, 3243.54 C. F. Luck and W. Gordy, ibid., p. 3240.5 5 R. Hoskins, J . Chem. Phys., 1956, 25, 788.56 A. Fava, P. B. Sogo, and M. Calvin, J . Amer. Chem. SOC., 1957, 79, 1078.57 S. I. Weissman, E. de Boer, and J. J. Conradi, J . Chem. Phys., 1957, 26, 963.Garif’yanov and B. M. Kozyrev, Zhur. eksp. teor. F i z . (U.S. translation), 1956, 3, 25512 GENERAL AND PHYSICAL CHEMISTRY.transiently under conditions such as those in a.n electric discharge, bytrapping them at low temperatures. The afterglow of active nitrogen, whenso condensed at 4" K, was shown 58 to contain free nitrogen atoms. Trappedradicals, thought to be H02 or possibly OH, have been detected by electron-spin resonance in products from a discharge.59 Though identification maynot be easy, there will clearly be much further work of this type.Nuclear Magnetic Resonance.-Papers on technique include details of ahigh-resolution spectrometer,co and treatments of magnet design 61 andstabilization.62 Especially notable is a spectrometer of high stability,a inwhich the master oscillator is locked to the resonant frequency of a controlsample in the magnetic field, the Larmor condition thus being preserved.The immense resolution now attainable is shown by the most refined workon ethanol,64 for which 26 lines are now resolved, some only 0.5 c./sec.apartat 30 Mc.jsec. Modulation at a frequency high compared with the spectralsplittings is suggested 65 for highly sensitive detection without loss of detail.Standardization of spectra is fully discussed,66 and small spin-spin couplingconstants can be measuredG7 by use of the "ringing patterns " on thespectral trace.Methods are given for heating the sample to temperaturesup to 300" c , ~ ~ and for cooling it to low temperature^.^^ Work at lowmagnetic fields is active, and a low-field spectrometer, chiefly suited tomeasurements of relaxation times, has been described.70 The method offree precession in Earth's field, in which nuclei of slightly different precessionfrequencies are revealed by beats in the decaying signa1,'l should be a usefuladjunct to normal methods. Spin-echo technique can be quite simplyapplied in Earth's field, with no special preca~tions,~2 for work on relaxationphenomena.Reviews of chemical aspects of nuclear magnetic resonance up to the endof 1956 are available.261 73Work continues on solids to determine internuclear distances, such as theinter-proton distance in the a i d e ion,7* and to study molecular motions.A number of papers deal with molecular mobility and crystallinity inpolymers, such as rubber.75 Line-widths have given information about58 T.Cole, J. T. Harding, J. R. Pellam, and D. M. Yost, J . Chem. Phys., 1957, 27, 593.R. Livingston, J. Ghormley, and H. Zeldes, ibid., 1956, 24, 483.6 0 €3. Primas and H. H. Gunthard, Helv. Phys. Acta, 1957, 30, 315; H. Primas,61 Idem, ibid., p. 331.6f Idem, Rev. Sci. Instr., 1957, 28, 510.63 E.B. Baker and L. W. Burd, ibid., p. 313.64 J. T. Arnold, Phys. Rev., 1956, 102. 136.6 5 K. Halbach, Helv. Phys. Acta, 1956, 29, 37; R. V. Pound, Rev. Sci. Instr., 1957,6 6 J. R. Zimmerman and M. R. Foster, J . Phys. Chem., 1957, 61, 282.67 C. A. Reilly, J . Chew. Phys., 1956, 25, 604.6 8 J. N. Shoolery and J. D. Roberts, Rev. Sci. Insbr., 1957, 28, 61.69 N. Fuschillo, ibid., 1956, 2'7, 394; L. N. Mulay, ibid., 1957, 28, 279.70 P. W. Mitchell and M. Eisner, ibid., p. 624.7 1 D. F. Elliott and R. T. Schumacher. J . Chem. Phys., 1957, 26, 1360.72 J. G. Powles and D. Cutler, Natuve, 1957, 180, 1345.73 J. E. Wertz, J . Phys. Chem., 1957, 61, 51.74 R. Freeman and R. E. Richards, TTans. Faraday SOC., 1956, 52, 802.7 5 H. S. Gutowsky, A.Saika, M. Takeda, and D. E. Woessner, J . Chem PAys., 1957,ibid., p. 297.28, 966.27, 534SHERIDAN : RADIO-FREQUENCY SPECTROSCOPY. 13rotational isomerism ; for instance, fluorine magnetic resonance in solidCFCl,*CFCl, indicates the gauche f0r11-p and configurations are assigned toCHCl,*CHCl, and CHBr,*CHBr, from proton resonance. 7 7 High resolutionis applied to similar problems, since spectra of liquids are also sensitive toconfigurational effects ; cases include gem-difluoroethanes, 78 where evidenceof restricted rotation is obtained and the temperature dependence of theresidence-times in various configurations can be studied, 79 dimethyl-formamide and dimethylacetamide,80 which have planar equilibriumskeletons, alkyl nitrites,81 of which cis and trans forms are detectable,and nitrosamines Ba where there is hindered rotation about the N-Nbond.Very large and structurally important field shifts occur 83 for fluorineresonances in crystals containing paramagnetic ions, notably in manganousfluoride, MnF,.Similar paramagnetic shifts even occur when the nucleusin resonance is separated from the paramagnetic ion by another atom,s4 forexample in the phosphorus resonance in lithium manganous phosphate,LiMnPO,. Paramagnetism is presumed to be placed on normally dia-magnetic atoms by exchanges involving the paramagnetic centre. Some-what similar is the shift 85 in proton resonance in nickelocene, (C,H,)2Ni, ashift many times greater than that in the diamagnetic molecules ferroceneor C5H5Ni*N0.86 The shift in nickelocene is explained 85 if the unpairedelectrons on the nickel spend about half their time on the aromatic rings;0-n interaction 49 is invoked to account for the shift's being towards higherfields (see also ref.37).In high-resolution nuclear magnetic resonance there are many structuraldiagnoses by means of chemical shifts and spin fine-structure. Fluorineresonance is effective in identifying 8' such arrangements as F-O-SO2-F,O=SF,, and F-O-SF, (all grouped fluorine atoms are spectroscopicallyequivalent). The P-H bond is shown to occur in phosphites 88 from phos-phorus resonance, and the covalent P-0-P linkage in the polyphosphates;phosphorus resonances in numerous other compounds have been related tostructure.89 The boron-11 resonance in B,HI1 demonstrates three groupsof boron atoms, and the proton resonance spectrum (simplified by saturation7 6 H.S. Gutowsky and M. Takeda, J . Phys. Chem., 1957, 61, 95.7 7 M. Takeda and H. S. Gutowsky, J . Chem. Phys., 1957, 26, 577. '* J . J. Drysdale and W. D. Phillips, J . Amer. Chern. SOC., 1957, 79, 319.79 P. M. Nair and J. D. Roberts, ibid., p. 4565.81 L. H. Piette and R. A. Ogg, jun., ibid., 1957, 26, 1341; W. D. Phillips, C. E.Looney, and C. P. Smeath, J . Molecular Sfiectr., 1957, 1, 35.82 C. E. Looney, W. D. Phillips, and E. L. Riley, J . Amer. Chew. Soc., 1957,79, 6136.H. S. Gutowsky and C. H. Holm, J . Chem. Phys., 1956, 25, 1228.R. G. Shulman and V. Jaccarino, Phys. Rev., 1957, 108, 1219.84 J .M. Mays, ibid., p. 1090.85 H. M. McConnell and C. H. Holm, J . Chem. Phys., 1957, 27, 314.8 6 T. S. Piper and G. Wilkinson, J . Inorg. Nuclear Chem., 1957, 4, 104.87 F. B. Dudley, J. N. Shoolery, and G. H. Cady, J . Amer. Chem SOC., 1956,78,568.8 8 C. F. Callis, J. R. van Wazer, J. N. Shoolery, and W. A. Anderson, ibid., 1957,79,2719.89 J. R. van Wazer, C. F. Callis, J. N. Shoolery, and R. C. Jones, ibid., 1956, 78,5715; J. R. van Wazer, ibid., p. 5709; N. Muller, P. C . Lauterbur, and J. Goldenson,ibid., p. 3567; J. R. Parks, ibid., 1957, 79, 757.R. Schaeffer, J. N. Shoolery, and R. Jones, ibid., p. 460614 GENERAL AND PHYSICAL CHEMISTRE'.of the boron spins) shows four groups of protons. Boron trifluoride com-plexes can be effectively studied 91 by means of their MR spectra of fluorineand other atoms.Proton resonance offers powerful assistance in thestructural diagnosis of carbohydrate derivatives. 92 A field of future activityis indicated in the measurement 93 of many magnetic resonance spectra forcarbon-13 in its natural abundance.Numerous papers deal primarily with spectral fine structures and theirexplanation. There are plenty of indications of the complexity of theeffects involved, and the difficulties which may attend their chemicalinterpretation. For example, some F-F and F-H spin-spin couplings arenot simply related to the structural separations of the atoms concerned.94Methods of determining the signs of coupling constants have been in-d i ~ a t e d . ~ ~ Deuterium substitution was used 96 in evaluating H-H couplingsin acetylene and methane which, for reasons of symmetry, are not obtaineddirectly. Anderson and McConnell 97 discussed the analysis of spectra forvarious spin systems, and Wilson 98 showed that the application of grouptheory to spin-spin coupling can be taken in part from the theory ofmolecular vibrations. Pople 99 has given particularly illuminating treat -ments of certain proton-resonance shifts.In acetylene, the shift to highfield is accounted for by the paramagnetic effect due to the mixing of theground state with excited states for field components across the molecularaxis. A similar effect, absent from methane, operates increasingly alongthe series NH,, H,O, and HF and largely cancels the opposing effect of ioniccharacter.In aromatic substances, this approach elaborates the conceptof ring-currents induced by fields perpendicular to the aromatic planes ;such currents are responsible for the diamagnetic anisotropy of thesemolecules. The shift to low field in benzene, and details of shifts in numerousfused-ring compounds, are rather satisfactorily accounted for. Pople,Bernstein, and Schneider lo0 also give detailed spectra and relevant theoryfor a number of spin-systems in which chemical shifts and spin-spin inter-actions are of comparable magnitude ; cases include o-dichlorobenzene,pyridine, deuteropyridines, methylpyridines, and azulene. The ring-curren ttheory has been applied to results for other aromatic systems.lo1 Chemical9 1 P.Diehl and R. A. Ogg, jun., Nature, 1957, 180, 1114.93, R. U. Lumieux, R. K. Kullnig, H. J . Bernstein, and W. G. Schneider, J . Avrzer.93 P. C. Lauterbur, J . Chenz. Phys., 1957, 26, 217; C. H. Holm, ibid., p. 707.g4 A. Saika and H. S. Gutowsky, J . Amer. Chew. SOC., 1956, 78,4818; C. M. Shartsand T. D. Roberts, ibid., 1957, 79, 1008.95 G. A. Williams and H. S. Gutowsky, J . Chenz. Phys., 1956, 25, 1288; H. S.Gutowsky, C. H. Holm, A. Saika, and G. A. Williams, J . Amer. Chem. SOC., 1957,79, 4590.9 6 M. Karplus, D. H. Anderson, T. C. Farrar, and 13. S. Gutowsky, J . Chem. Phys.,1957, 27, 597.9 7 W. Anderson and H. M. McConnell, ibid., 1957, 26, 1496.9B E. B. Wilson, jun., ibid., 1957, 27, 60.9 9 J. A. Pople, ibid., 1956, 24, 1111; Proc.Roy. SOC., 1957, A , 239, 541, 550; H. J.Bernstein, W. G. Schneider, and J. A. Pople, ibid., 1956, A , 236, 515.100 H. J. Bernstein, J. A. Pople, and W. G. Schneider, Canad. J . Chem., 1957, 35,65; J. A. Pople, W. G. Schneider, and H. J. Bernstein, ibid., p. 1060; W. G. Schneider,H. J . Bernstein, and J. A. Pople, ibid., p. 1487.101 J. S. Waugh and R. W. Fessenden, J . Amer. Chem. Soc., 1957, 79, 846; G.Hazato, J . Chenz. P h y s , 1957, 27, 605.Chenz. SOC., 1957, 79, 1005SIIERID-IN RBDIO-FREQUENCY SPECTROSCOPY. 15shifts in the ions C,H,- and C,H,+ show some influence of the overallcharge.lo2 The shielding of fluorine nuclei attached to aromatic rings is,not unnaturally, more c0mplex.10~ A further case in which chemical shiftshave been satisfactorily related to the theory of electronic states is incobaltic c0mplexes.l0~ The shifts in cobalt resonance arc related linearly tothe wavelength of the lowest-frequency optical absorption maximum ; thisis the relationship predicted from ligand-field theory lo5 if the shifts are dueto mixing, by the magnetic field, of a low-lying paramagnetic state with theground state.Relations between chemical shifts and molecular and group propertiesare being sought.The screening at o-, m-, and P-protons in monosubstitutedbenzenes has been compared 106 with the orientating effects of substituents.The shieldings of fluorine in substituted fluorobenzenes are correlated lo’with separate inductive and resonance contributions to Hammett’s sigmafunctions of the substituents.Proton resonance shifts in methyl halidesare a linear function of the electronegativities of the halogens,lo8 and shiftsin other methyl derivatives are used to assign an electronegativity sequenceto the attached groups.Several papers concern solvent effects and complex formation. A provedinfluence of the medium on chemical shifts log indicates the need for cautionin the choice of solvent and any internal standard of reference. Complex-formation of olefinic and aromatic substances with chloroform is studiedby measurement of the resonance of the chloroform protons, and the theoryof ring-currents in the aromatic molecules is used to suggest details of theinteraction. Similar studies have been made of chloroform in the presenceof electron donors such as triethylamine.111 Important effects of hydrogen-bonding are observed in the chemical shifts of proton resonances in hydroxylderivatives, the simplest case being the comparison of the shift for water inthe gaseous 112 and the liquid state.A striking movement of the hydroxyl-proton resonance occurs in ethanol solutions as the degree of hydrogenbonding is varied.113 Ilydrogen-bonding shifts in phenol, substitutedphenols, and acetic acid 114 are correlated with known steric, intramolecularand solvent influences.The effectiveness of variousparamagnetic ions in broadening the chlorine resonance in chloride solu-tions115 has been related to the rapidity of solvent exchange around theSeveral studies relate to rates of processes.lo2 J.R. Leto, I;. A. Cotton, and J. S. Waugh, Nature, 1957, 180, 978.lo3 T. Isobe, K. Inukai, and K. Ito, J . Chem Phvs., 1957, 27, 1215.lo4 R. Freeman, G. R. Murray, and K. E. Richards, Pvoc. Roy. Soc., 1957, A , 242,455.lo5 J. S. Griffith and L. E. Orgel, Tram. Favaduy Soc., 1957, 53, 601.lo’ R. W. Taft, jun., ibid., 1957, 79, 1045.lo* A. L. Allred and E. G. Rochow, ibid., p. 5361.lo9 A. A. Bothner-By and R. E. Glick, J . Chem. Phys., 1957, 26, 1647, 1651;110 L. W. Reeves and W. G. Schneider, Canad. J . Chem., 1957, 35, 251.111 G. J. Korinek and W. G. Schneider, ibid., p. 1157.112 R. A. Ogg, jun., Helv. Phys. Acta, 1957, 30, 89.113 A. D. Cohen and C. Reid, J . Chem. Phys., 1956, 25, 790.114 C. M. Huggins, G. C. Pimentel, and J.N. Shoolery, J . Phys. Chem., 1956,115 J. E. Wertz, J . Chem. Phys., 1956, 24, 484.1’. L. Corio and B. P. Dailey, J . Amer. Chent. Soc., 1956, 78, 3043.P. L. Corio and B. P. Dailey, ibid., 1956, 25, 1291.60, 131116 GENERAL AND PHYSICAL CHEMISTRY.paramagnetic ion. Rates and mechanisms of fast protolyses have beenstudied 116 by high-resolution techniques, and chemical shifts have beenused to study equilibria 11' involving methylamines. A number of exchangeprocesses were detected, such as those involving the fluorine atoms in chlorinetrifluoride and iodine pentafluoride,Il8 and in boron trifluoride complexes. 91Proton resonance was applied to water adsorbed on titanium dioxide lI9and to methane on the same adsorbent,120 and related to structural featuresof the adsorbed layers.Further applications of this type are to be expected.Nuclear Quadrupole Resonance.-This field has some resemblance tonuclear magnetic resonance, but complexities associated with the necessityof working with crystalline substances have so far kept chemical interest innuclear quadrupole resonance at a lower level. In the selection of the worknow mentioned, results of predominantly crystallographic interest have beenexcluded. A general review of nuclear quadrupole coupling has beengiven.121Chlorine quadrupole resonances continue to be measured. In (PNC12),and (PNC12), there is evidence122 of two P-C1 distances. In tungstenhexa- and tetra-chloride the low chlorine coupling 123 has led to a suggestedrevision of the nature of the bonds.Chlorine quadrupole resonances inchlorinated heterocylic molecules and (CICN), have been discussed interms of electronic effects; the inductive effect of =NH- in the ring showsas a 10% increase in resonant frequency. Work on all the polychloro-benzenes is complete ; 125 the chlorine quadrupole resonance frequencyacquires increments proportional to the number of substituents ortho to thechlorine. A correlation is indicated between the frequency shifts relative tochlorobenzene and Hammett's sigma functions of substituents. A similarsituation occurs with the bromine quadrupole resonances in polybromo-benzenes.126 Bromine and iodine quadrupole resonances have been measuredin numerous benzene derivatives,12' and also correlated with the sigmafunctions.A series of papers on the halides of aluminium, gallium, and indium isnotable for the variety of types of quadrupole resonance employed.Thebromine resonance in Al,Br, shows 128 the presence of both bridge andterminal bromine atoms, and has been interpreted in terms of ionic characterin the bonds. Similar effects are shown by the iodine resonances in the+iodides of aluminium, gallium, and indium.129 Bromine, gallium,E. Grunwald, A. Loewenstein, and S. Meiboom, J . Chem. Plays., 1957, 27,117 A. Loewenstein and S. Meiboom, ibid., p. 641.11* E. L. Muetterties and W. D. Phillips, J . Amer. Chem. SOC., 1957, 79, 322.llQ J. M. Mays and G. W. Brady, J . Chem. Yhys., 1956, 25, 583.lZ0 N. Fuschillo and C.A. Renton, Nczture, 1957, 180, 1063.121 W. J. Orville-Thomas, Quart. Rev., 1957, 11, 162.122 K. Torizuka, J . Phys. SOC. Japan, 1956, 11, 84; H. Negita and S. Satc123 R. P. Hamlen and W. S. Koski, ibid., 1956, 25, 360.Chem. Phys., 1956, 24, 621.124 G T . <pup1 R C Ramps and P 1 Rrav ihid n 1 R R f i . H. Ncwitn 2nd S-and067.u, J .J' ---.7* " - " - - J r- - - - - 7 0--- ---- -- -. -. "-bv*, --. -. I--u - .Satou, ibid., 1957, 27, 602.125 P. J. Bray, R. G. Barnes, and R. Bersohn, ibid., 1956, 25, 813.127 G. W. Ludwig, ibid., p. 159.lZ8 R. G. Barnes and S. L. Segel, ibid., p. 180.129 S. L. Segel and R. G. Barnes, ibid., p. 578.P. A. Casabella, P. J. Bray, S. L. Segel, and R. G. Barnes, ibid., p. 1280THIRSK: ELECTROCHEMISTRY. 17indium resonances are also reported for gallium bromide and iodide andindium bromide and iodide.130The single iodine resonance in iodine trichloride is thought l3I to be dueto the ion ICl,+ in the structure 1Cl2+ICl4-, the iodine in IC1,- beingexpected to show only small nuclear coupling. The chlorine quadrupoleresonance frequencies in IC1,- and IC1,- are 132 only about half the frequencyin iodine monochloride, and an electronic explanation is suggested.Fine structure in the quadrupole resonance of elementary iodine 133 isinterpreted in terms of electron-coupled spin-spin interaction.The first case of a sharp change in quadrupole resonance frequencyaccompanying a phase transition is reported; 134 in 1 : 2 : 4 : 5-tetrabromo-benzene the bromine resonance frequency changes sharply by 0.15y0, withhysteresis, as temperature is variednear 40” C.ELECTROCHEMISTRY.J.S.SIKCE the last Report 1 a number of books of interest have appeared; twoconcern dipole moments and dielectric behaviour,2a, and there are animportant text on electrolyte solution^,^ a detailed treatment of metalelectrodeposition,* a wide survey at an elementary level,5 and a compilationof essays relevant to electrochemistry in biology and medicine.6 Theproceedings of the 1954 and 1955 meetings of C.I.T.C.E. have beenpubli~hed.~~j The 54th meeting of the Bunsen-gesellschaft was devoted tostudies of electrochemical phenomena at metal electrodes.8 Discussionswere held by the Faraday Society on membrane phenomena 9a and inter-action in ionic solution^.^^ Several reviews of current work on electrolytesolutions leu, a and electrode processes lla, have appeared, one by Delahay 11*130 R.G. Barnes, S. L. Segel, P. J. Bray, and P. A. Casabella, J . Chem. Phys. 1957,26, 1345.131 S. Hagiwara, I<. Kato, Y. Abe, and M. Minematsu, J . Phys. SOC. Japan, 1957,132 C. D. Cornwell and R. S. Yamasaki, J . Chem. Phys., 1957, 27, 1060.l33 S. Kojima, S. Ogawa, S. Hagiwara, Y. Abe, and M. Minematsu, J . Phys. SOC.ls4 F. B. Johnson, Nature, 1956, 178, 590.12, 1166.Japan, 1966,11, 964.J. N. Agar and J. A. B. Randles, Ann. Reports, 1954, 51, 103.( a ) J. W. Smith, “ Electric Dipole Moments,” Butterworths Scientific Publications,London, 1955; (b) C. P. Smyth, “ Dielectric Behaviour and Structure,” McGraw-HillBook Co.Inc., New York, 1955.3 R. A. Robinson and R. H. Stokes, I ‘ Electrolyte Solutions,” Butterworths Scien-tific Publications, London, 1955. * H. Fischer, “ Elektrolytische Abscheidung und Elektrokristallisation von Metal-len,” Springer-Verlag, Berlin, 1954.E. C. Potter, “ Electrochemistry Principles and Applications,” Cleaver-HumePress Limited, London, 1957.“ Electrochemistry in Biology and Medicine,” ed., T. Shedlovsky, Chapman andHall, Ltd., London, 1955.( a ) International Committee of Electrochemical Thermodynamics and Kinetics,6th Meeting, Butterworths Scientific Publications, London, 1955 ; (b) InternationalCommittee of Electrochemical Thermodynamics and Kinetics, 7th Meeting, Butter-worths Scientific Publications, London, 1957.( a ) Discuss.Faruda-v SOC., “ Membrane Phenomena,” 1956, 21; (b) Discuss.Faraduy Soc., “ Interaction in Ionic Solution,” in the press.lo ( a ) 0. Redlich and A. C. Jones, Ann. Rev. Phys. Chem., 1955, 6, 71; ( b ) R. A.Robinson and R. H. Stokes, ibid., 1957, 8, 37.l1 (a) D. C. Grahame, ref. 10a, p. 337; (b) P. Delahay, ref. lOc, p. 229.* 2. Elektrochem., 1955, 59, 59318 GENERAL AND PEYSIC-41, CHEMISTRY.being particularly systematic in its treatment. Frumkin has reviewed workon the effect of adsorption on electrochemical kinetics 12a and on electrodekinetics with the object of showing the close connection with the generalkinetics of chemical reactions in solution.12b Van Rysselberghe haspublished a monograph on the thermodynamics of reversible and irreversibleelectrochemical ~ystems.1~Although the volume of work in electrochemistry is now considerable werestrict this Report essentially to anodic processes, including evolutionof oxygen and phenomena allied to passivation; the latter has receivedlittle attention in previous reviews and reports.In addition some recentstudies on double layers which are particularly relevant to electrode processeshave been included.Oxygen overvoltage hasbeen examined at high current densities on nickel and electroplatedcobalt.14b, With nickel, current densities up to 10 A/cm.2 in 7*5~-potassiumhydroxide were employed, over a temperature range of 0-55" c. Atransmission coefficient, a, of 0.45 was assumed and quite close agreementwas obtained between the calculated and expected value for 2.3RTlaP (ca.61 yo) which indicated a similarity between oxygen and hydrogen dischargesat high current densities.Cobalt was heavily oxidised and, unlike nickel,readily gave a steady overvoltage. A somewhat unusual reaction schemewas suggested to account for the experimental observations on the kineticsof evolution of oxygen on cobalt, involving the formation of hydroxylradicals and atomic oxygen as intermediates. Oxygen overvoltage at anickel anode has also been studied by Mine, Seiyama, and Sakal.15 Limit-ing currents have been determined with platinum, platinised platinum,palladium, palladised palladium, iridium, and gold in B~-sulphuric acid withand without hydrogen present in the solution.16 The depolarisation ofoxygen has been examined as a function of the orientation and structure ofsingle-crystal tin electrodes,17 and on graphite and porous carbon surfaces.l*Oxygen overvoltage was determined in concentrated perchloric acid l9 andin perchloric acid of concentrations up to 9 .8 ~ and sulphuric acid to 1 5 ~ . ~ In the latter work 20a it was concluded that the rate of evolution of oxygendepended on the rate of decomposition of the oxide formed on the surfaceand that the evolution proceeded through formation of an anion. A studyof the r81e of the acid anion is planned with use of oxygen-18. The r6le ofsurface oxides has been investigated with oxygen-18 by Rosenthal andl2 ( a ) A. N. Frumkin, Us@ekhi KJzim,, 1955, 24, 933; ( b ) " Voprosy Khim. Kinetiki,Kataliza, i Reaktsionnoi Sposobnosti," Akad.Nauk S.S.S.R., 1955, p. 402.l3 P. Van Rysselberghe, " Electrochemical Affinity," Hermann and Co., Paris, 1955.l4 (a) Ya. I. Turyan and I. S. Gol'denshtein, Zhur. priklad. Khim., 1956, 29, 379;( b ) Ya. I. Turyan and I. A. Gershlrovich, ibid., p. 600; ( c ) idem, J . Appl. Chem. U.S.S.R.,1956, 29, 69.l5 T. Mine, T. Seiyama, and W. Sakal, J . Chew. SOC. Japan, I n d . Clzem. Sect., 1955,58, 725.l6 XI. Breiter, C. A. Knorr, R. Meggle, 2. Elektrochem., 1955, 59, 153.l7 V. N. Nikulum and S. M. Kochergin, Zhur. fiz. Khirn., 1956, 30, 2337.l9 T. R. Beck and R. W. Moulton J . Electrochem. SOC., 1056, 103, 347.2o ( a ) R. I. Kaganovitch, M. A. Gerowith, and E.Emkeev, Doklady Akad. NaukS.S.S.R., 1956, 108, 101; ( b ) K. I. Rosenthal and V. I. Veselovskii, ibid.. 1956, 111,637: ( c ) M. Anbar and H. Taube, J . Amer. Chein. Soc.,1956, 78, 3252.Anodic Processes.-(a) Evolution of oxygen.N. N. Voronin and 0. V. Izbzkova, Ukifain. Klzirn. Zhur., 1956, 22, 446THIRSK ELECTROCHEMISTRY. I9Veselovskii,20b who examined the reaction on what they described as aPtO-type oxide, formed a t 0.8-1-2 v, and one of PtO[O], type formed at1-3-1.5 v in N-sulphuric acid. Oxygen-18 was evolved from the latterearly in the electrolysis but the platinum oxide remaining did not participatesubsequently. The fractionation of isotopes of oxygen at anodes wasexamined by Anbar and Taube.,Oc The isotope fractionation factor foroxygen from water depended on the electrode material and was determinedon nickel, iron, palladium, cobalt, copper, manganese, silicon, tin, gold,silver, platinum, lead, and carbon.The range of discrimination was from0.35% for tin to 1-8 for iron, and over a limited range was independent ofcurrent density and almost independent of the acidity or basicity of theelectrolyte. They suggest that the overall isotope discrimination liesin the exchange reaction M-OH + H20* ---+ M-*OH -+ H20 and kineticdiscrimination in the succeeding step of formation of an oxygen-hydroxylgroup bond. Once this bond is formed they assume that the peroxide willlead unidirectionally to O,, and that, for certain metals at least, the rate ofevolution of oxygen is determined by formation of an -0-O- bond, ratherthan the M-OH bond as suggested by Delahay.21c With lead dioxide andmanganese dioxide deposits none of the lattice oxygen appears as oxygenmolecules.Izgaryshev and Yefinov 21a investigated the dependence of thekinetics of oxygen evolution on smooth platinum on sulphuric acid con-centration and the degree of oxidation of the platinum.21b They suggestthat the divergence of results by different operators depends on the degreeof preliminary anodic polarisation of the electrode, and they determinedthe effect of this on the Tafel slope " b ". Pre-polarisation for 1 min.changed b from 0.156 to 0.115 for all acid concentrations; it remainedconstant after 15 min., but " a " shifted to higher potentials. Theyconsidered that the formation and decomposition of a platinum-oxidecombination at the surface was an essential stage in the process of theelectrochemical evolution of oxygen.The longer the preliminary polaris-ation the stronger the Pt-0 bond and the greater the overpotential. Theresult seems to be somewhat at variance with the theoretical study byRuetschi and Delahay,21c unless interpreted as relating the overvoltagewith the degree of oxidation. Ruetschi and Delahay state that thevariations in overvoltage arise primarily from variations in the energy of theM-OH bond, which they calculate, but decrease approximately linearlywith increasing bond energy. This was verified by them by using Hicklingand Hill's data 21d for silver, gold, cadmium, cobalt, copper, iron, nickel,cobalt, lead, palladium, and platinum polarised in N-potassium hydroxide.There was no correlation between oxygen overvoltage for different metalsand the corresponding work functions.The effect of surface-active additives on the oxygen overpotential onsmooth platinum was investigated by Kheifets and Rivlin.22 Bockris 23a21 ( a ) N.A. Izgaryshev and E. A. Yefinov, Zhur. $2. Khim., 1956, 30, 1807; ( b )idem, ibid., 1606; ( c ) I>. Ruetschi and P. Delahay, J . Chew. Phys., 1955, 23, 556; ( d )A. Hickling and S. Hill, Discuss. Faraday Soc., 1947, 1, 236.22 V. L. Kheifets and I. Ya. Rivlin, Zhur. pyiklad. Khim., 1956, 29, 69.23 (a) J. O'M. Brockris, J . Chew. Phys., 1956, 24, 819; (b) J. A. Christiansen, Z .phvs. Cheni., 1936, B, 33, 145; 1939, 37, 37420 GENERAL AND PHYSICAL CHEMISTRY.employs the Christiansen relations 2a to obtain expressions for the kineticsof an electrode process containing any number of intermediate steps; themethod was applied to oxygen evolution.This approach is of interest, butof value only if the Christiansen relations are justifiably employed. Bockrisand Huq studied oxygen evolution, by the constant-current method, onbright platinum electrodes in ultra-pure sulphuric acid in the absence andpresence of sodium sulphate. The overall anodic reaction is confirmed as40H- - 4e __t 0, + 2H20. Experiments were carried out on theattainability of the reversible oxygen electrode. A steady potential of1.24 & 0.03 v was observed in solutions with less than 10-11 mole/l.ofimpurity i.e. by extrapolation to zero current and identified with the thermo-dynamically calculated reversible potential for the overall reaction 0, + 2H,O + 4e Evidence is produced that the rate-controlling step isdischarge of OH- or H,O.A.C. methods were employed by Becker and Breiter 25a to study oxygenevolution on platinum in sulphuric acid and alkali solutions. Over thepotential range 0.4-2v a value of 10-80 pF/Cm.' is quoted for thepredominantly capacitative A.C. impedance, and this is ascribed to theslightly frequency-dependent capacity of the double layer. The voltage-capacity curve showed two maxima, indicating that the composition of thedouble layer is strongly affected by adsorption of oxygen, which is directlydemonstrable by cathodic charging curves.Impedance measurements werediscussed in connection with a determination of anion adsorption.25bEvaluation of the charging curve in O-G~-sulphuric acid at a cathodic currentdensity of 0.1 A/cm.2 suggested a coverage of the electrode by oxygen whichincreases continuously above 0-8 v. A roughness factor of 1.5 being assumed,the presence of a monatomic PtO layer is deduced at 1.4 v, and a diatomiclayer at 2.1 v, in the region of oxygen evolution. Balashova 256 investigatedmore particularly adsorption of anions (S042-) on a platinised-platinumsurface; the experimental method was described in detail. The activity ofelectrode and solution was determined by using H235S0, and the resultsindicated the coexistence of a rapid adsorption of sulphate ion on theplatinum surface with a slow process caused by the ions' interacting withthe surface.The effect of alternating current on anodic processes with platinumelectrodes was studied theoretically by Llopis and Colom,26 and Praeger 27measured the A.C.impedance of a platinum electrode in alkali halidesolutions as a function of polarising voltage and frequency. The behaviourof aluminium, chromium, hafnium, niobium, tantalum, vanadium, titanium,and zirconium anodes at very low current densities before oxygen is evolvedwas examined by H. A. Johansen et aZ.28The complexity of40H-.(b) The formation of oxides and insoluble salts.24 J. O'M. Bockris and A. K. S. Huq, Pvoc. Roy. SOC., 1956, A , 237.277.25 (a) M. Beckerand M. Breiter, 2. Elektrochem., 1956, $0, 1080; (b) N. A. Balashova,26 J. Llopis and F. Colom, Anales Fiz. Quim., 1955, 51, B, 379.2 7 M. J . Praeger J. Electrochem. Soc., 1957, 104, 454.28 H. A. Johansen, G. B. Adams, and P. Van Rysselberghe, J. Eleckochem. SOC.,Doklady Akad. Nauk S.S.S.R., 1955, 103, 639.1957, 104, 339THIRSK : ELECTROCHEMISTRY. 21anodic processes of this kind has made them a less attractive experimentaland theoretical study than, for example, the cathodic phenomena ofhydrogen evolution and metal deposition, or even oxygen overvoltage.Earlier methods of investigation led to a situation summarised byW. J. Miille1-.~9 Development in ideas of semiconduction in inorganicmaterials and the increasing use of structural techniques are helpful informulating more reliable models of the various systems that may beencountered. This, together with the introduction of a wider variety ofelectrochemical techniques, is leading to progress in the study of thesedifficult problems.This is of considerable value in view of the importanceof these systems to electrochemical cells and corrosion.Thermodynamic studies defining the regions for the existence andcoexistence of deposits on metal electrodes and the ions in solution havebeen studied extensively by Pourbaix and his collaborators ; the principlesand methods involved have been described,30 and many of the newer datafor a variety of systems are in the publications of the Centre Belge d'gtudede la Corrosion and in the C.I.T.C.E.proceedings.Some advances in the study of the mechanism of anodic oxide formationwith high fields can be illustrated by work on aluminium, tantalum, niobium,and an antimony-indium alloy. Much use has been made in the interpret-ation of these anodic studies of a theory of oxidation advanced by Cabreraand M ~ t t , ~ l and later extended by Dewald 32 to include the effect of a space-charge in the oxide. Cabrera and Mott assumed that every ion escapingfrom the metal is swept right through the oxide by the high field applied andthat a single barrier at the metal-oxide interface controls the current andhence the rate of growth. Consequently the Tafel slope (6E/6 In i)T whereE is the field should be directly proportional to T , the absolute temperature,and inversely proportional to the product of the charge on the ion and thebarrier half-width. Young 33a examined films formed with a constantcurrent on niobium between 0" and 90" with a field strength of the order of106v/crn.and stated that the Tafel slope is independent of T. A similarresult for tantalum was obtained by V e r m i l ~ e a . ~ ~ ~ Jacobs,34 however,reported that in non-aqueous solvents the Tafel slope does fall off in therange 0" to -63". These results are all interpreted in terms of Dewald'stheory. It was pointed out that the effect of the space-charge causes achange from control at the metal-oxide interface to control by migrationas T increases; at low and high temperatures respectively the Tafel slopeshould be proportional to T , and at intermediate temperatures such as thoseemployed by Young the variation with T is too slight to be detected.Inthe case of niobium Young considered that there was evidence for aZ g W. J. Muller, " Die Bedeckungstheorie der Passivitat der Metalle uad ihre3O M. Pourbaix, " The Thermodynamics of Dilute Aqueous Solutions," English31 N. Cabrera and N. F. Mott, Rep. Pvogr. Physics, 1949, 12, 163.32 J . F. Dewald, J . Electrochem. Soc., 1955, 106, 1.33 ( a ) L. Young, Trans. Faraday Soc., 1956, !52, 502, 515; ( b ) D. A. Vermilyea,34 W. M. Jacobs, Discuss. Faraday Soc., "Molecular Mechanisms of Rate Pro-experimentelle Begrundung," Verlag Chemie, Stuttgart, 1934.translation by J. N. Agar, Edward Arnold and Co., London, 1949.Acta Metallurgica, 1953, 1, 282.cesses in Solids," 1957, 23, 22022 GENERAL AND PHYSICAL CHEMISTRY.space-charge effect ; also, the observed dependence of space-charge on currentdensity corresponded to the case in Dewald’s theory in which the “ jump ”distance for diffusion into the oxide was less than for diffusion through theoxide..The data were explained with reasonable values for all parametersexcepting that the jump distances were of the order of 6-8 A and thereforetoo large; it was suggested that polarisation forces affect the field strength.The formation of oxide on tantalum has been studied extensively byVermilyea;35 the oxide film was formed even when the metal was heldnegative to hydrogen; 35a the activation energy for formation of Ta20,is not a single linear function of the applied field; 35b and capacitancemeasurements did not give an unambiguous decision concerning thn,presence of a ~pace-charge.~~~ Although a mechanism for the growth wassuggested,35b the nucleation process was not satisfactorily explained.D e ~ a l d , ~ ~ using zone-refined crystals of an antimony-indium alloy, showedthat the oxidation rate in 0-1N-potassium hydroxide depended markedlyon the crystal face.At low fields (111) and (332) faces oxidised more thanten times as quickly as (110), ( i l l ) , and (332) faces. At high fields all facesoxidise at the same rate; the data were interpreted in terms of the detailedstructure of the alloy and the theories of oxide growth referred to.31932Pronounced crystallographic effects observed at low fields and their absenceat high fields establish the location of the rate-limiting process. At lowfields passage into, and at high fields passage through, the film is the difficultstep.The oxides formed had an approximately 1 : 1 indium : antimonyratio in spite of the solubility of Sb,03 in the electrolyte. The experimentalresults throw doubt on a simple interstitial-ion transport mechanism.The anodic dissolution of semiconductors of controlled electricalproperties is of great interest and both germanium and silicon have beeninvestigated. A large voltage barrier was observed at about 0 * 8 m ~ / c m . ~at room temperature on the %-type but not the $-type germani~m.~’ Thisvoltage barrier, of 3 ohms cm.-1, broke down at about 0 v in manyelectrolytes.During dissolution the surface appeared to be covered withapproximately a monolayer of oxide or hydroxide. The mechanismsuggested for the anodic dissolution involved two holes and two electronsfor each germanium atom dissolving. With silicon the oxide was formed byanodisation in potassium nitrate solutions with N-methylacetamide as solvent .38With use of more conventional electrodes, a wide variety of anodicphenomena are revealed by studies with silver, mercury, lead, and nickeland all these metals have continued to be investigated in detail.Theanodic formation of the halide layer on polycrystalline silver in hydrochloricacid and rearrangement phenomena on reduction were examined by Jaenickeet al.; 39 elsewhere,40 the primary object was to establish a reliable techniqueSilver has been investigated in both acid and alkaline solutions.35 (a) D. A. Vermilyea, J . Electrochem. Soc., 1954, 101, 389; ( b ) 1955, 102, 207;36 J. F. Dewald, ibid., 1957, 104, 244, 257.37 D. R. Turner, ibid., 1956, 103, 252.39 W. Jaenicke, R. P. Tischer, and H. Gerischer, 2. Electrochem., 1955, 59, 448.40 M. Fleischmann, J. Sowerby, and H. R. Thirsk, Trans. Faraduy SOL, 1957,53,91.( c ) ibid., p. 655; ( d ) ibid., 1956, 103, 690; ( e ) 1957, 104, 140.P. F. Schmidt and W. Michel, ibzd., 1957, 104, 230THIRSK: ELECTROCHEMISTRY. 23for preparing surfaces containing single-crystal faces for subsequent anodis-ation; a phenomenon of cathodic smoothing was observed and optimumsmoothing conditions were determined for reproducibility during the anodicstage Ag _+ AgC1.Pospelova et aZ.41 observed that the oxides producedelectrochemically were less stable than those arising from direct oxidation.The behaviour of silver 42 in sulphuric acid closely resembles that of thelead-sulphuric acid system ; for example, oxidation proceeded by the stagesAg I t was thought that the Ag,O whichwas present was formed by decomposition of AgO together with traces of 3cubic sub-oxide, postulated from crystallographic evidence. It appearsthat in some ways gold behaves rather like silver; there is evidence 43 thatgold polarised in O-lN-sulphuric acid, in a phosphate buffer of pH 6.8, andin 0.1 M-sodium carbonate, has three oxidation steps, Au 4 Au,O--+AuO -+- Au,O,; In potassiumhydroxide solutionsM the stages in oxidation appear to be Ag-A g , O d A g O and analogy is again shown with the lead-lead sulphatesystem in that the Ago is formed primarily from the first formed passivatinglayer (Ag,O), siiice subsequent formation of Ago proceeds at an efficiencyof <1%.The reproducibility of the Tafel slope for evolution of oxygen onthe higher oxide was fair, giving a = 0-39 & 0.01.The dissolution of mercury at very low current densities has been studiedby a new technique 45 and a rate constant for dissolution of 0.476 cm. sec.-lis reported. The initial stages in the anodic formation of calomel have beenstudied in detail by Dibbs et u Z ., ~ ~ with interesting additional evidence (seeref. 47) for the production of a " metastable " high-energy form of calomelbefore '' rafts '' of calomel are formed. The crystallographic structure ofanodically-formed films of mercurous chloride and bromide has been workedout in considerableThe passivation of lead was cxamined by using increments of appliedvoltage in 40.50, 22-80, and 2.99~-solutions of phosphoric acid 49 and it wasconcluded that the passivating layers formed were, progressively, leadphosphate (unspecified) -+- PbO __t PbO, followed by evolution ofoxygen. With the current constant, the overall steps in the anodepotential-time relations can be explained in terms of the stepwise oxidationof Pb to Pb4+. In contrast, Briggs and Wynne-J~nes,~~ investigating thepassivation of lead in halide solutions by electrochemical and opticalmethods, found that the electrochemical formation of compounds on theelectrodes, other than halides (PbCl,, etc.), was rare except in thc case of41 I.N. Pospelova, A. A. Rakov, and S. Ya. Pshezhetskii, ZFzuv. $2. Khinz., 1956,30, 1433.42 P. Jones and H. R. Thirsk, Trans. Faraday SOC., 1954, 50, 732.43 S. E. S. El Wakkad and A. M. Shams El Din, J., 1954, 3098.44 P. Jones, H. R. Thirsk, and W. F. K. Wynne-Jones, Trans. Favaday SOC., 1956,45 S. E. S. El Wakkad, T. M. Salem, and S. E. Khalafalla, J . , 1955, 1702.4 6 H. P. Dibbs, D. J. G. Ives, and R. W. Pittman, J., 1957, 3370.4 7 S. Hillsand D. J . G. Ives, J., 1951, 311.4 8 H. R. Thirsk, Proc.Phys. SOC., 1953, B, 66, 129; E. H. Boult and H. R. Thirsk,J. Kanecki, Z. Zambura, and J. Trau, Bull. Acad. polon. Sci. Classe 111, 1955,3, 37.5 0 G. W. D. Briggs and W. F. K. Wynne-Jones, J., 1956, 2966.Ag,SO, -+ Ago + O,(g).formation of AuO, was not suspected.52, 1003.Trans. Faraday SOC., 1964, 50, 40424 GENERAL AND PHYSICAL CHEMISTRY.potassium iodide solutions, and evidence for a passivating oxide layer wasvery slight.Reactions in the lead-N-potassium hydroxide system were shown toproceed51 in the stages (i) Pb-PbO, (ii) PbO--+PbO, + someoxygen, (iii) predominantly oxygen evolution. Linear portions of the plotof overpotential against In (current density) for oxygen evolution gavecc = 0.5 for the Tafel slope. The anodic formation of lead sulphate in the lead-sulphuric acid system and subsequent oxidation to lead dioxide were examinedkinetically, in some detail, by use of a new method with step-wise increase inthe controlled o~ervoltage.~~ Rate constants for the rate of nucleation andthe rate of growth were determined for the phase change PbSO, --+ PbO,.The actual structure of electrochemically formed lead dioxide is stillreceiving attention and earlier work 53 in which a second, rhombic form wasdescribed has received additional confirmation by Butler.54 Bode andV O S S ~ ~ also report rhombic PbO, together with the usual tetragonal 8modification in the positive electrode of the accumulator and show itsstructure to be related sterically to the red form of PbO and to lead; form-ation of the p form is favoured by high acidity, as confirmed by s.J. €301~.56The deposition of the oxides from nitrate, acetate, and perchlorate solutionsunder conditions of controlled overpotential has been investigated byFleischmann and Liler.57 In this work the effect of pH, lead-ion con-centration, and neutral salts on the kinetics of nucleation and the growth ofthe oxide centres has been measured and the relative incidence of the twoforms of the oxides has been clarified.Nickel has been studied in both acid and alkaline solutions. Thechemistry of the nickel hydroxide-oxide system is particularly hfficult.Trumpler and Saxer 58 worked with nickel anodes in sulphuric acid solutions(N and 5 ~ ) and with dilute ( 0 . 2 ~ ) sulphuric and nickel sulphate solutionscontaining O-O5~-nickelous chloride. In dilute sulphuric acid containingchloride ion there is a potential barrier above which a current peak showsthe end of passivation.Landsburg and Hollnagel 59 measured passivationtimes in sulphuric acid solutions with improved reproducibility by previouslyreducing the nickel at 500" in hydrogen. Acid concentration and theoccluded hydrogen considerably influence the nature of the passivation.Treatment of the metal at different temperatures changes the effectiveanodically active surface, the passivated surface probably being an oxygen-containing compound. Oxygen is evolved on the completely passivatedsurface produced at a sufficiently high pH. Pomosova and Gurevich 6oexamined the effect of chloride ions on the dissolution of nickel anodes.61 P.Jones, H. R. Thirsk, and W. F. K. Wynne-Jones, T r a m . Faraday Soc., 1956,52 M. Fleischmann and H. R. Thirsk, ibid., 1955, 57, 71.53 I. Zaslavskii, Y. D. Kandrashov, and S. S. Tulkachev, Doklady Akad. Nauiz54 G. Butler, personal communication.5 5 H. Bode and E. Voss, 2. Elektrochem, 1056, 60, 1053.5 6 S. J . Bone, Ph.D. Thesis, University of Durham, 1957.5 7 M. Fleixhmann and M. Liler, Trans. Faraday Soc., in the press.5 8 G. Trumpler and W. Saxer, Helv. Chim. Acta, 1956, 39, 1733.59 R. Landsburg and M. Hollnagel, 2. Elektrochem., 1954, 58, 680; 1956, 60, 1098.6 o A. V. Pomosova and L. T. Gurevich, Zhur. priklad. Khim., 1956, 29, 1372.52, 1004.S.S.S.R., 1950, '75, 559THIRSK : ELECTROCHEMISTRY.25Conditions for forming reproducible nickel hydroxide electrodes havebeen examined 62a together with their behaviour in potassium hydroxidesolutions. The coulombic efficiency can approach 100% and the oxidationproceed to NiO,.,; a reduction to NiO,.,, is only possible with the thinnestlayers. Analysis of the oxide layers suggested a composition gradientto account for the divergence between open-circuit potentials and the ratioof 0 : Ni available for reduction. An electrode of nickel with a layer offreshly prepared nickelous hydroxide can be oxidised easily but after ageingonly with difficulty; on nickelous oxide there seemed to be only a surfacereaction.61c Briggs 62 has examined structural modifications in depositedp-NiO*OH brought about in the presence of different cations (K, Na, Ba,Sr, and Ca) in the forming electrolyte, a nickel salt solution buffered byacetate.The behaviour of iron has been studied under a wide range ofconditions. Bonhoeff er and his collaborators examined the effect of acidconcentration,639 e4 anodic diss0lution,6~ and kinetics in acid neutral andalkaline solutions.66 The kinetics have also been studied in the presence ofsulphate ions 67 and phosphoric acid e8 and, with particular reference topassivation, in oxalic and acetic acid and their sodium salt solutions, and inthe presence of sulphate and chloride i0ns.6~ The effect of inhibitor^,^^acceleration of the dissolution by ferric ions,'l passivity in 73 andthe effect of alkaline mono- and poly-sulphides have been considered.Makrides et al.have also made kinetic studies.74 The potentials of passiveiron have been i n t e r ~ r e t e d , ~ ~ the impedance of the layer on passive iron innitric acid has been measured,76 and the potential differences within thepassivated layer 7 7 and the relations between ionic current and the internalpotential discus~ed.~~ Combined A.C. and D.C. measurements have beeninterpreted by electrical circuit analogue methods. 79The nature of the passivating layer on aluminium has been examined insulphuric acid solutions,sO as affected by iron at grain boundaries,sf and61 (a) G. W. D. Briggs, E. Jones, and W. F. K. Wynne-Jones, Trans. Faraday Soc.,1955, 51, 1433; (b) E. Jones and W. F. K.Wynne-Jones, ibid., 1956, 52, 1260;(c) G. W. D. Briggs and W. F. K. Wynne-Jones, ibid., p. 1272.62 G. W. D. Briggs, J., 1957, 1846.63 K. F. Bonhoeffer and K. E. Heusler, 2. phys. Chem. (Frankfurt), 1956, 8, 390.64 K. G. Weil and K. F. Bonhoeffer, ibid., 1955, 4, 175.65 K. F. Bonhoeffer and K. E. Heusler, 2. Elektrochem., 1957, 61, 122.66 K. F. Bonhoeffer, ibid., 1955, 56, 594.87 M. Serra and S. Feliu, Anales F k Quim., 1954, 50, B, 937; W. H. Wade and N.6 8 J. Kameski and 2. Sambura, Bull. Acad. polon. Sci., Cl. 111, 1956,4,107; Roczniki69 M. Serra and S. Feliu, Anales Fis. Quim., 1955, 18, 395, 401, 405.70 E. Rau, Diss. Abs., 1956, 16, 331; C. V. King and E. Rau, J . Electrochem. Soc.,71 H. C. Gatoo, ibid., p. 286.72 K. J. Vetter, 2. Elektrochem., 1955, 59, 67.73 M.Stern and R. M. Roth, J . Electrochem. Soc., 1957, 104, 390.74 A. C. Makrides, N. M. Komodros, and N. Hackerman, ibid., 1955, 102, 363.75 M. J. Pryor, ibid., p. 163.76 L. Gougerot and R. Alfieri, J . Chim. filzys., 1955, 52, 382.7 7 K. I. Vetter, 2. phys. Chem. (Frankfurt), 1955, 4, 165.78 K. G. Weil, 2. Elekfvochem., 1955, 59, 711.79 H. J. Engell and B. Illschner, ibid., p. 716.8 o I. V. Kratoo, Zhur.fiz. Khim., 1954, 28, 1450.81 T. Murakawa, J . Electrochem. Soc. Japan, 1956, 21, 18.Hackerman, Trans. Faraday Soc., 1957, 53, 1636.Chew., 1957, 31, 185.1956, 103, 33126 GENERAL AND PHYSICAL CHEMISTRY.by pH changes and chloride and nitrate ions.S2 Overvoltage for dissolutionof copper in 0.1M-perchloric acid has been related to a calculated rate constantby El Wakkad et aZ.; 43 the rate constant of 3-6 x cm.set.? is to becompared with the value of 4.5 x cm. sec.-l obtained by a differentmethod.83 In concentrated phosphoric acid it has been concluded that thestep Cu __t Cu2+ is rapid, Cu + Cu2+ __t 2Cu+, slow.@ Anodic studiesin solutions of cyanide, chloride, and thiosulphate ions giving stable coppercomplexes show 85 that the primary electrode process is Cu _t Cu+ + e.Goswami,86 using (1 10) single-crystal faces in alkaline solutions, states thata porous Cu20 layer is first formed followed by an outward migration ofcopper ions.Single crystals of hafnium in nitric acid show that the growth depends onorientation of the substrate and that the layers become discontinuous as theacid concentration increases from 70% to Chromium 88 and zinc 89both show a complex anodic behaviour but without additional features ofgeneral interest.The Electrical Double Layer and Related Problems.-The determinationof the potential of the electrocapillary maximum is necessary for anadequate study of reactions taking place on the conductor-solution inter-face ; experimental methods have been reviewed.Several determinationshave been made recently on materials other than mercury. The zero-charge potential at a lead dioxide electrode has been determined by acapacitance 92 and also by a pendulum hardness method 93a described byVenstrem et aZ.,93b who discussed the results of other investigator^.^^^ Themeasurements by the first procedure were carried out in 0.01~- and N-sulphuric acid and N-oxalic acid on lead dioxide plated on gold; the recordedpotential was 1 .8 0 ~ versus the normal hydrogen electrode. The phaseshift was high at frequencies above 1000 c./sec., indicating that polarisationhad little effect on the measured impedance, but, after strong anodic polaris-ation, the oxygen discharge potential became inore negative, indicating theeffects of adsorption. The pendulum hardness method, which can be usedin concentrated solutions, gave a zero-charge potential in O-lN-sulphuric82 A. R. Tourky, E. M. Khairy, and hf. K. Hussein, J . Chinz. phys., 1956, 53, 433.133 J. B. Randles, Trans. Faraday Soc., 1952, 48, 137.84 D. Laforgue-Kantzer, J . Chinz.phys., 1955, 52, 314.85 D. J. Rogers, J. Kleinberg, and A. W. Davidson, J . Inorg. Nucleav chem., 1957,86 A. Goswami, J . Sci. Ind. Res., India, 1956, 15, B, 340.87 R. A. Misch and E. S. Fisher, J . Electrochem. Soc., 1956, 103, 153.8 8 T. Heumann and W. Rosenor, 2. Elektrochem., 1955, 59, 722; I. M. Issa andH. Khalifa, J . Indian Chem. SOL., 1956, 33, 465, 471; I. M. Issa, H. Khalifa andI. A. Ammar, J . Phys. Chenz., 1955, 54, 592; Ya. M. Kolotyrkin and V. M. Knyazhiva,ZJaur. $2. Khirn., 1956, 30, 1990.89 T. Inone, M. Sato, and R. Ishii, J . Electvochem. Sac. Japan, 1954, 22, 679;T. P. Dirkse, J . Electrochem. Sac., 1955, 102, 497; M. Schwabe, Metalloberjlache, 1957,37, 1.91 B. N. Kabanov, I. G. Kiseleva, and D. T. Leikis, Doklady Akad. Nauk S.S.S.R.,1955, 99, 805.O2 M.A. Vorsina and A. N. Frumkin, ibid., 1939, 24, 918.93 (a) D. I. Leikis and E. I<. Venstrem, ibid., 1957, 112, 97; (b) E. K. Venstrem,V. I. Likhtman, and P. A. Rehbinder, ibid., 1956, 107, 105; (c) J. O’M. Bockris andR. Parry- Jones, Nature, 1953, 171, 930.4, 115.A. N. Frumkin, 2. Elektrochem., 1955, 59, 507THIRSK : ELECTROCHEMISTRY. 27acid within 0.1 v of the above (1.9 v vs the normal hydrogen electrode) butin 8N-sulphuric acid the potential was displaced towards 1.7 v because ofadsorption. The more marked asymmetry of the plots of hardness againstpotential in the dilute solutions at positive potentials was tentativelyassociated with change in surface structure and an increase in area due toadsorption. The precise crystallographic form of the PbO, was not stated;it could have been either the cc or more probably the form and it would beof interest to seek for differences in the electrocapillary maxima of thesetwo modifications.The bubble method has been employed by Ukshi and Levin 94 inpreliminary measurements to establish the zero-charge potential on copperand chromium. From the preliminary results it was considered that thevalue lay between 0.07 and 0-02 v for copper and 0.02~-0.04 v for chromium.In this particular case the information was sought in connection with theeffects of anions during electrodepo~ition.~~ The figure for copper does notagree particularly well with the value quoted in a very interesting paper byKheifets and Kra~ikov,~6 who studied the effect of pH on the zero-chargepotential of a large number of metals.They used an A.C. method tomeasure capacitance over a wide range of frequency and decided that metalsfall into two groups: those which do not absorb hydrogen and for whichthe zero-charge potential is independent of pH (Zn, Cd, Hg, Ag, and Cu),and those absorbing hydrogen and for which there is a marked pHdependence (Fe, Ni, Co, Pd, and Pt). A further investigation concerningthe validity of these results would be of great interest; for example, in viewof the cathodic ,behaviour of single crystals of silver *O it seems possible thatthe behaviour of some of the metals in the first group was rather a functionof their crystalline state than a fundamental difference in behaviour.According to Ruetschi and Delahay 97 the potential of zero charge withrespect to a reference electrode varies linearly with the work function for anideal polarised electrode whilst this potential for a reversible electrode isindependent of the nature of the electrode.This is confirmed from theliterature ; they include in the first class silver, cadmium, copper, gallium,mercury, nickel, lead, and platinum and in the second class thallium,silver, gold, copper, mercury, and platinum. For perfectly polarisedelectrodes the difference between the Volta potentials from electrode tosolution at zero charge is ca. -0.33 v. The difference between the Galvanipotentials is equal to the surface potential of the electrode. For areversible electrode, diff erences of Volta potentials at zero charge varylinearly with the electronic work function.Oel and Strehlov 98 also statethat there are two potentials at which a metal is uncharged; one impressedon the electrode by polarisation, the state being characterised by a maximumin the surface tension-the Lippmann potential; the other at unpolarisedelectrodes established by transfer of potential-determining ions-the Billiter94 E. A. Ukshi and A. I. Levin, DokEady A k a d . Nauk S.S.S.R., 1955, 105, 119.95 A. I. Levin and E. A. Ukshi, ibid., 1953, 89, 1045.g6 V. L. Kheifets and B. S. Krasikov, ibid., 1956, 109, 586.9 7 P. Ruetschi and P. Delahay, J . Chem. Phys., 1955, 23, 697.H. J. Oel and H. Strehlov, 2. phys. Chenz. (Frankfurt), 1954, 1, 241; and par-ticularly idem, ibid., 1955, 4, 8928 GENERAL AND PHYSICAL CHEMISTRY.potential. Experimental results given in the literature are discussed.Anoverall impression gained from papers containing such speculations is thata really thorough and critical examination of published experimentalresults, particularly from early sources, is very necessary. Grahameet aLS9 examined the impedance of lead and tin electrodes by employing the“ frozen drop ” method.l0*9 The dispersion of capacity was small anddepended on the smoothness of the surface; the dispersion of resistance wasmuch larger and was independent of the potential, showing that one is notdealing with Faradaic admittance. The dependence of capacity on potentialroughly parallels that of mercury.The possible effect of water moleculeson the behaviour of the capacity of the double layer at mercury-solutioninterfaces as a function of frequency was examined by Bockris et aZ.lol Theexperimental results can be interpreted if it is assumed that the motion ofthe water molecules that are absorbed on the electrode is so restricted thattheir relaxation time is large enough to fall within the frequency range ofmeasurement.There have been several very interesting contributions to the problemof the specific adsorption of ions and also the anomalous displacement ofthe potential of the electrocapillary maximum on mercury with change inactivity of the surface-active anion-the Esin and Markov effectGrahame has extended the analysis of the problem advanced by Ershler 102bin which allowance is made for the discreteness of the absorbed ionic chargetogether with multiple reflections within the double layer.This treatmentis presented in two papers; the first 103a theoretical, the second containingimportant new experimental r e ~ u l t s . 1 ~ ~ ~ Ershler’s results are confirmedand extended and in addition equations are developed connecting thepotentials within the inner region of the double layer with experimentallyaccessible data. Parsons lo4 derives an adsorption isotherm for specificallyadsorbed ions and demonstrates that Stern’s use of the Langmuir model isincorrect. The use of an empirical isotherm based on a virial type ofequation of state with a square-root term and the Amagat isotherm lead toagreement with experiment.In Parsons’s later paper lo5 on the Esin andMarkov effect this thermodynamic approach is developed and it is shownthat the effect can be obtained not only at the electrocapillarity maximumbut at any point in the electrocapillary curve. An empirical equation of thesame form as the Temkin isotherm lo6 is satisfactory for moderate coverageof adsorbed anions. The new results obtained by Grahameloa withgg D. C. Grahame, R. E. Ireland, and R. C. Petersen, Technical Report t o 0. N. R.1956, No. 22.l o 0 T. Borisova, 33. V. Ershler, and A. N. Frumkin, J . Phys. Chern. U.S.S.R., 1948,925; T. Borisova and B. V. Ershler, ibid., 1950, 24, 337.lol J. O’M. Bockris, W. Mehl, B. E. Conway, and L. Young, J .Chem. Phys., 1956,25, 776.Io2 ( a ) 0. A. Esin and B. F. Markov, Acta Physe’cochim. U.S.S.R. 1939, 10, 353;( b ) B. V. Ershler, J . Phys. Chem. U.S.S.R., 1946, 20, 679.l o 3 ( a ) D. C. Grahame, Technical Report to the 0. N. R., No. l., 1957; ( b ) idem,ibid., No. 5, 1957.1°4 R. Parsons, Tmns. Furaduy SOC., 1955, 57, 1578.lo5 Idem, Proc. 2nd Internat. Congres on Surface Activity, vol. 3, London, 1958.lo8 M. I. Ternkin, Zhuv. fiz. Khim., 1941, 15, 296; S. Brunauer, J . Amer. Chem.Soc., 1942, 64, 757THIRSK : ELECTROCHEMISTRY. 20the mercury-potassium iodide system permitted detailed calculations,suggested previously,lo1 and a further development in the theory. Grahameconfirms Parsons's suggestions for the relation between the surface excessof specifically adsorbed anions, d, and log a, although he found that theisotherms could not be superimposed by displacement along the log a, axis.In addition the differential capacity related to the inner region of the doublelayer, measuring the capacity of that region under conditions such that theconcentration of adsorbed ions within it remain constant, gives valuespractically independent of d.If this capacity C" is independent of ni thenit should be independent of the identity of the anion as well, since in thelimit when ni = 0 the identity of the anion can make no difference. Plotsof the differential capacity for the inner region for potassium fluoridetogether with C for potassium iodide were made and, at negative valuesof the charge, the curves were identical and for positive values the agree-ment was still almost within the limits of experimental error.The remark-able conclusion from these calculations is that the field generated by theadsorbed anions has little effect upon the capacity of the inner region. Thisconstant value of C" enabled Grahame to calculate essentially completelythe properties of the inner region of the double layer. Furthermore aquantitative treatment is given of Frumkin's 107 suggestion that anions arepulled towards the metal as it acquires a positive charge.Several papers have been published on theoretical and experimentaltreatments of methods in which the current is interrupted, a matter of long-standing interest in the study of electrode processes.Grahame lo8 andScott log examined the problem theoretically; the treatment is limitedto electrodes without passivating layers. It was concluded lo* that infavourable cases the following parameters can be calculated; the I R drop,the capacity of the double layer, a lower limit to the product of the con-centration of the major reactant and its specific rate reaction constant, anda weighted average of the forward (+) and backward (ib) components of thecurrent : iav = aij + (1 - a)&.Scott log examined the interpretation of potential-time curves when thediffusion in one or both phases plays a major r61e. Publications by Fischer,Seipt, and Morlock lloU and particularly papers by Seipt and Gierst lloCconstitute a valuable examination and analysis of current interrupterexperimental methods.The Reporter thanks his colleagues for discussions, Dr.R. Parsons for kindlylending manuscripts of papers in the press, and Dr. Milica Liler who translateda number of the Russian papers referred to in the report.H. R. T.lo' A. N. Frumkin, Trans. Furuduy SOC., 1940, 36, 117.lo* D. C. Grahame, J . Phys. Ghem., 1953, 57, 257.lo9 W. T. Scott, J . Ckm. Phys., 1955, 23, 1936.110 (a) H. Fischer, M. Seipt, and G. Morlock, ref. 7a, p. 239; ( b ) M. Seipt, ref. 7b,p. 67; ( c ) L. Gierst, ref. 7b, p. 4930 GENERAL AND PHYSIC.4L CHEMISTRY.KINETICS OF CHEMICAL CHANGE.Kinetics in the Gas Phase.-The numerous publications in this field during1957 are considered under four headings-theoretical, techniques, inorganicsystems, and organic systems.Work on explosions and flames is notincluded.Theoretical. The Boltzmann equation has been considered from astatistical-mechanical point of view.l Chang has suggested a new methodfor determining the order and velocity constant of a reaction, and Flynnsuggests that many reactions in which the order changes during an experi-ment can be represented by &/dt = K ( l - x ) ~ . (1 - EX)”. He describeda method for calculating the constants I<, p, a, and V. The theory ofconsecutive reactions has been discussed,* and Monoszon has givenmathematical functions and relations that permit solution to give the rateconstants of the separate steps in a mixture of gases in which there are 3number of simultaneous reactions. Integrated rate equations for variousmechanisms by which three substances are interconverted by first-orderreactions have been derived as an interpretation of isotopic exchange in thepresence of an overall chemical reaction.6 The validity of the stationary-state approximation in the kinetics of chain reactions has been investigated.’Hirschfelder finds that it is accurate if the rates of destruction of theactive intermediates are rapid.Various Russian workers * have examinedthe theory of branched-chain reactions, especially the case of delayedbranching. Enikolopyan 8c has been able to explain why the rate of oxid-ation of some hydrocarbons is constant to a high percentage of reaction andalso why they end before all the reactants are used.Stepukhovich has calculated the activation energy of the decompositionof isopropyl, tert.-butyl, vinyl, and ally1 radicals, and has also investigatedthe effect of temperature on the steric factors of first- and second-orderreactions from the basic equations relating collision and transition-statetheories.He considers that this effect may be very important in free-radical reactions. The pre-exponential factors of hydrogen abstraction(e.g., CH,. + H,, CD,. + CH,) and reactions of chlorine atoms have beencalculated by means of the transition-state theory.l0, l1 The structureand mechanical properties of the activated complex for the former areassigned from a set of empirical rules from molecular structure andspectroscopy, and there was good agreement with experiment within thelimits of error involved.1°M.S. Green, J . Chem. Phys., 1956, 25, 830.2 W. Chang, J . Phys. Chem., 1957, 61, 819.3 J . H. Flynn, ibid., p. 110.4 M. Talat-Erben, J . Chem. Phys., 1957, 26, 75.A. M. Monoszon, Trudy Moslaov. Automobi1.-Dorozh. Inst. im. V . M . PIolotova,R. A. Albertyand W. G. Miller, J . Chem. Phys., 1957, 26, 1231.1956, No. 18, 227; Chem. Abs., 1957, 51, 5515.7 ( a ) J , 0. Hirschfelder, ibid., p. 271; ( b ) J. G. Giddings, ibid., p, 1210.8 ( a ) Yu. S. Sayasov and A. B. Vasil’eva, Zhur. $2. Khim., 1955, 29, 802; (b) N. S.Enikolopyan, ibid., 1956, 30, 769; (c) idem, Doklady Akad. Nauk S.S.S.R., 1957,112, 93.A. D. Stepukovich, Zhur. $2. Khim., 1956, 30, 2387; Doklndy Akad. NaukS.S.S.R., 1956, 107, 436.D.J . Wilson and H. S. Johnston, J . Anzer. Chem. SOC., 1957, 79, 29.11 K. S . Pitzer, ibid., p. 1804KINETICS OF CHEMICAL CHANGE. 31Long 1, has suggested that the value (9-2 kcal./mole) found by Majury andSteacie l3 for the activation energy of CH,. + H, _+ CH, + H* may below owing to the formation of methane from a methyl radical and ethane.The equilibrium constants for hydrogen abstraction by trideuteromethylfrom methane and methyl from tetradeuteromethane and [l*C]methaneat 300", 450", and 600" K have been calculated from spectroscopic data.14Combined with the velocity constants for the first two forward reactionsthey give the velocity constants for the back reactions. Trotman-Dickenson15 has plotted log k for the reaction of methyl radicals withhydrocarbons against log k for the analogous reactions of trifluoromethyl.Two straight lines, both of unit slope, are obtained.An analysis of thestructure of the =CEO group has been used as a basis for understanding theprimary process in the photolysis of saturated aldehydes and ketones,especially those containing propyl or larger groups,16 and Calvert l7concludes from a discussion of the decomposition of formyl (HCO*) andacetyl (CH,CO*) radicals that the activation energies are either about 27 and1s or 15 and 10 kcal./mole respectively.niIoseley and Robb 18 have developed a valuable methodfor determining the rate constants of free-radical reactions by following thenon-stationary state in simple photoinitiated gas reactions.They measurethe change in pressure due to adiabatic temperature changes by means of adiaphragm manometer of sensitivity mm. Hg and time delay responseless than sec. Using acetone they determined a value of k forXH,* __t C2H, in good agreement with that of earlier workers. A non-optical shock-tube technique for studying kinetics at high temperatures hasbeen developed at the Cornell Aeronautical Lab0rat0ry.l~ It is a single-pulse method, the gas being allowed to remain at reaction conditions for acontrolled time and then cooled very rapidly. Flash spectroscopy has beenused to detect free radicals in the wake of a shock wave.20 The range ofconcentration and wavelength over which a photochemical reaction can bestudied is increased if a mirror is used to reflect the transmitted light backinto the system.21 Jucker and Rideal 22 have described a simple and novelxenon lamp, and Callomon and Ramsey 23 a microsecond flash-photolysisapparatus. An exploding wire, emitting light rich in ultraviolet in<1 millisec., has been used as a line source in flash p h o t ~ l y s i s .~ ~ Theresults are very reproducible.Two spectrometers which give the mass-spectrum of a gas diffusingthrough a pin-hole from a reaction system 20 or 60 times per secondl 2 L. 11. Long, J . Phys. Chem., 1957, 61, 821.l3 T. G. Majury and E. \V. R. Steacie, Canad. J . C h e w , 1952, 30, 800.l4 F. S. Deinton, K. J. Ivin, and F. Wilkinson, Tyans. Faradny SOC., 1957, 53, 1204.l5 A. F. Trotman-Dickenson, Chewz.and Ind., 1957, 1243.l6 P. P. Manning, J . Amer. Chem. SOC., 1957, 79, 5151.l8 F. Moseley and J. C . Robb, Proc. Roy. SOC., 1957, A , 243, 119, 130.lY €1. S. Glick, J. J. Klein, and W. Squire, J . Chem. Phys., 1057, 27, 850.2 3 C. E. Cambell and I. Johnson, ibid., p. 316.21 J . A. Davies and P. P. Manning, J . Amer. Chem. SOC., 1957, 79, 5148.22 H. Juckerand (Sir) E. K. &deal, J., 1957, 1068.23 J . H. Callomon and D. A. Ramsey, Canad. J . Phys., 1957, 35, 120.24 G. K. Oster and R. A. Marcus, J . Chem. Phys., 1957, 27, 189.He favours the lower values.Techniqztes.J. G. Calvert, J . Phys. Chem., 1957, 61, 1206TABLE 1. A rrhenius parameters of homogeneous elementary reactionsReactionH,O, --t 2OHO*+O,+M+O,+M03+M.+O2+O.+M0. + 0, --t 202F, + IF5 + IF,2Br + A(0,) + Br, + A(OA21 + A ---+ I, + A2CIO* + C12 + 0 2CIO.+ CI,O ---t CIO, + CI,CIO- + CI,O --t CI + 0 2 + CI,N2+ 0.- NO + NN.+ NO--+, N,+ 0.No + NO + N, + 0.N. + 0, + NO + 0.NO + 0- --t NO,NO + O.+ M -+ NO, + MNO,+C + M - w N O , + MNO0 j- 0.- NO + 0 21\!32 + 0. --t NO 3- 0 2NO*+ 0*+NO + 0 2NO+O2+NO~+NOs+NO,NtOS + NO, + NO,NO2 + CO --t NO + COZMethod *SSI F J 1 F1)- Sh-l \ NJ ] PhNSISF ,A (or k or P )(c.c., moles, sec.)(4.61 & 0.25) x 10151013(2.96 -I: 0.21) x 1013(6.00 & 0.33) X 1013---k = (2.4 0.4) x lolok = l o s tP - 0.06k = 5.3 x 107k 2 4 x 10'1f-' k>1013-2 x 1012k = 1.8 x 10l6k = 1.0 x l O " tk = 2.1 x 1012k>1012 tk = 6-58 x lo7P N lo-'1013.1-14.11.2 x 1013* S, Static; T , thermal decomp.of 0,; F, flash photolysis; F,, flash photolysis ofshock tube reaction N, + 0, f- 2NO; N , flow reaction of N atoms a t low pressure:I, infrared spectrometry. t At room temperature. 8 At 25" CKINETICS OF CHEMICAL CHANGE. 33have been de~cribed.~~ Kistiakowsky and Kydd 25a state that with theirinstrument a component present at a mole fraction of 0.005 can be observedin a single spectrum with reasonable certainty. Hisatsune, Crawford, andOgg 26 have described a fast scanning infrared spectrometer.Reed and Rabinovitch 27 have used a spherical source, namely a hollowsteel sphere with 24 perforations uniformly placed, to study sodium flamereactions. This reduces the theoretical difficulty of calculating velocityconstants but the average value for the reaction of sodium with methylchloride is higher than that for nozzle flames.The transfer of energy is obviously important in gas-phase reactions, sowe may mention that Arnold, McCoubrey, and Ubbelohde 28 have calculatedthe probability for de-excitation of vibration in a collision from theexperimentally determined relaxation times for energy transfer betweenvibration and translation in various gases.Inorganic systems.Many of these systems have been investigated andthe kinetics of some elementary processes are given in Table 1.By investigating the effect of wall coating on the hydrogen-oxygenreaction Warren38 has been able to find the relative efficiencies of surfacestowards destruction of He, Om, *OH, H02*, and H202.The photolysis ofwater vapour at temperatures up to 270" c with light of wavelength about1650 A gives hydrogen, oxygen, and hydrogen peroxide in varying amountsdepending on the geometry of the ~ystern.~9 The decomposition of hydrogenperoxide below 20 mm. in static and flow systems in carefully cleaned glassreaction vessels becomes homogeneous above 400-450" ~ . ~ ~ 9 40 The actualkinetics are however not in complete agreement. Benson and Axworthy 30consider that at about 100" c the kinetics of the thermal decomposition ofozone in the presence of gases such as carbon dioxide, nitrogen, or heliumcan be explained without postulating an energy chain. The photolysis bylight of short wavelength appears to be a photon-propagated reaction.41In flash photolysis vibrationally excited oxygen molecules in the groundelectronic state are formed and possess sufficient energy to decompose ozone2 5 ( a ) G.B. IGstiakowsky and Y. H. Kydd, J . Amev. Chena. SOC., 1957, 79, 4826;26 I. C. Hisatsune, B. Crawford, and R. A. Ogg, J . Amer. Chew. SOC., 1957,2 7 J . F. Reed and B. S. Rabinovitch, J . Cheim. Phys., 1957, 27, 988.28 J. W. Arnold, J. C. McCoubrey, and A. R. Ubbelohde, Trans. Favaday SOC.,2 9 P. A. Gigukre and I. D. Liu, Canad. J . Chew., 1957, 35, 253.30 S. W. Benson and A. E. Axworthy, J . Chew. Phys., 1957, 26, 1718.32 J. Fischer and R. K. Steunenberg, J . A m e v . Chewz. SOC., 1957, 79, 1876.32 I<. L. Strong, J.C. W. Cltien, P. E. Graf, and J . E. Will~rd, J . Chena. Phys.,33 F. 11. C . Edgecornbe, I<. G. W. Xorrish, and B. A. 'I'hrusli, I'm-. Roy. Soc., 1957,( b ) L. B. Blanchard, J . B. Farmer, and C. Ouellet, Cmzad. J . Chem., 1957, 35, 115.79, 4648.1957, 53, 738.1957, 26, 1287..1, 243, 82.G. B. Kistiakowsky and G. G. Volpi, J . Chcm. Yhys., 1957, 27, 1141.:rs H. W. Ford and N. Endow, ibid., p. 1156.n o J . D. Ray and R. A. Ogg, ibid., 1057, 26, 984.L 7 H. S. Johnston, W. A. Bonner, and D. J. Wilson, ibid., p. 1002.3 8 D. R. IVarren, ?'vans. Faraday SOC., 1957, 53, 199.M. C. Clien and H. A. Taylor, J . Chem. Phys., 1957, 27, 857.4 0 C. N. Satterfield and T. W. Stein, J . Phys. Chern., 1957, 61, 537.41 S. W. Benson, J . Chern. Phys., 1957, 26, 1351.REP.-VOI,.LIV 34 GENERAL AND PHYSICAL CHEMISTRY.molecules to give chains involving atoms and energised andMcGrath and Norrish question the mechanism for the thermal decom-position suggested by Benson and A x ~ o r t h y . ~ ~The rate of dissociation of bromine in the presence of argon, and thevisible emission from hot, partly dissociated bromine produced by a shockwave, have been studied at 1200-2500" K . ~ ~ , ~ ~ The activation energy ofthe reaction is approximately equal to the dissociation energy of bromine,and from the frequency factors it appears that both vibration and rotationof the molecule contribute to the diss~ciation.~~ The continuous emissionis caused by the re-formation of bromine molecules in various excitedstates.& The velocity constants for the third-order recombination of iodineatoms up to 160" c determined by flash photolysis agree with earliervalues3, The reaction of hydrogen with bromine at 850-1140" K in ashock tube above the explosion limit has been in~estigated.~~ The low-temperature reaction scheme with extrapolated values of the individualreaction constants (Table 1) explains the results.Much work has been reported on systems involving nitrogen compounds.The spontaneous ignition and luminescent decomposition of hydrazoic acid,HN,, have been studied.4G Bell, Robinson, and Tren~ith,~' who haveinvestigated the decomposition of nitrous oxide in the presence of carbondioxide, sulphur hexafluoride, and inert gases at 650-750", consider that itfollows activation by two processes: (1) 2N20 _t.N20* + N,O and(2) N20 + X - N,O* + X, E , - El being ca. 3 kcal./mole. There hasbeen some discussion on the rBle of nitrogen trioxide, NO,, in thedecomposition of the dioxide.48 The effect of foreign gases on thedecomposition of dinitrogen pentoxide in the presence of excess of nitricoxide within a limited pressure range is in general conformity withLindemann's the0ry.~9 The kinetics of the reaction of nitric oxide withhydrogen at 850-1060" c indicate that a chain mechanism operates.50 Thereaction of nitrogen dioxide with hydrogen at around 400" c has beenstudied by Ashmore and Levitt 51 and by Rosser and Wise.52 The kineticresults and the free-radical chain suggested by both pairs of workers agree,the overall activation energy determined being nearly the same, 43 and46 kcal./mole respectively.The oxidation of ammonia by nitrogen dioxideat 327-527" c in a static system has been followed by measuring the changein optical density of the latter.53 The reaction was of the second orderwith an overall activation energy of 27.5 kcal./mole. The effect of carbon42 W. D. McGrath and R. G. W. Norrish, Pvoc. Roy. SOC., 1957, A, 242, 265; Nature,43 H. B. Palmer and D. F. Hornig, J . Chem. Phys., 1957, 26, 98.44 H. B. Palmer, ibid., p. 648.4 5 M. N. Plooster and D. Garvin, J . Amer. Chem. SOC., 1956, 78, 6003.4 6 P. Gray and T. C. Waddington, Nature, 1957, 179, 576.4 7 T. N. Bell, P. L. Robinson, and A. B. Trenwith, J., 1957, 1474.48 N.Davidson and G. L. Schott, J . Chem. Phys., 1957, 27, 317; Y. G. 14shmore49 J. Jack, Trans. Faraday Soc., 1957, 53, 41.5 0 W. M. Graven, J . Amer. Chem. SOC., 1957, 79, 3697.5 1 P. G. Ashmore and B. P. Levitt, Trans. Furaduy SOC., 1957, 53, 945.52 W. A. Rosser and H. Wise, J . Chew. Phys., 1957, 26, 571.53 Idem, ibid., 1956, 25, 1078.1957, 180, 1272.and B. P. Levitt, ibid., p. 318KINETICS OF CHEMICAL CHANGE. 35mass (12C and 13C) on the rate of oxidation of carbon monoxide by nitrogendioxide decreases slightly with temperature; k12/k13 = 1.022, 1.019, and1.016 at 267", 365", and 454" c re~pectively.~~have investigated the combustion of hydrogensulphide by flash photolysis and kinetic spectroscopy. If little inert gasis present sulphur dioxide is formed by steps involving *SH and *OH, butwith a large excess or at a low temperature mainly disulphur dioxide, S202,is obtained. The photodecomposition of carbon dioxide by 1470A xenonradiation to give carbon monoxide does not involve atomic oxygen.22 Theeffect of phosphine on the ignition limits of mixtures of carbon monoxideand oxygen has been studied.55 If the rate of association of BH, radicals iscomparable with that of CH, radicals, then the results from eight studies ofkinetics of reactions of diborane lead to compatible upper limits for the heatof dissociation of diborane, B2H,.56 Hydrogen and tetraborane are themajor products of the mercury-photosensitised decomposition of diboranea t 2 9 .3 " c . ~ ' The primary step is probably B2H, + Hg* B2H, +He + Hg.A preliminary investigation of the photolysis of pentaboranevapour has been reported.58Organic systems. The few systems which appear to involve simple uni-or bi-molecular reactions are discussed first. Weston 59 has studied thetritium isotope effect in the isomerisation of cyclopropane. At 406-4 9 2 " c/200 mm. the ratio of the velocity constants of the unlabelled to thatof singly-labelled species is 0.86 -& 0.06 exp (-385 -& 95/RT), and as thepressure is decreased the effect is reduced. The relation of the results toSlater's calculations 6o is discussed. The pyrolysis of ethylcyclobutane,giving ethylene and but-l-ene, and the elimination of formic acid fromtek-butyl formate are unimolecular processes, k being 3.6 x 1015 exp(-62,00O/RT) and 10ll.l exp (-36,40O/RT) sec.-l respectively.619 e2 Themercury-photosensitised decomposition of ethylene to acetylene andhydrogen appears to involve the primary formation of a triplet C2H,molecule, which isomerises to a molecule of uncertain lifetime in whichtwo hydrogen atoms act as bridges between the carbon atoms.63 Hydrogenis formed from these two hydrogen atoms.The kinetics of the pyrolysis ofNorrish and ZeelenbergH ,C-C H,-N+O\ ///nitroethane below 440" c in a flow or a static system fit the equation k =1010.8 exp ( - 3 9 , 7 0 O / R T ) sec. and Wilde 64 considers that the main processinvolves a direct splitting-off of nitrous acid, the activated complex having54 R. G. W. Norrish and A. P.Zeelenberg, Proc. Roy. SOC., 1957, A , 240, 293.5 5 F. I. Dubovitshii and M. F. Kuz'mina, Zhur. $2. Khirn., 1956, 30, 83756 S H Bauer, J Amer. Chern. SOC., 1956, 78, 5175.57 T. Hirata and H. E. Gunning, J . Chern. Phys., 1957, 27, 477.68 H. B. Burwasser and R. N. Pease, J . Phys. Chem., 1956, 60, 1589.59 R. E. Weston, J . Chern. Phys., 1957, 26, 975.6 0 N. B. Slater, Proc. Roy. Soc., 1953, A , 218, 224.61 R. E. Wellman and W. D. Walters, J . Arner. Chern. SOC., 1957, 79, 1542.6 2 E. Gordon, S. J. W. Price, and A. F. Trotman-Dickenson, J . , 1957, 2813.63 E. Whalley, Canad. J . Chem?., 1957, 35, 565.6j K. A. Wilde, J . Ph;>ls. Chew., 1957, 01, 385TABLE 2.Reaction MethodCH,* ---t CH,: + H*CH,: + H, ---t CH,(CH3)4C + CH3* + C4He Pyrolysis of neopentaneCH3. + CH,.CO*OCH, --t CH4 + .CH,*CO.OCH,A rrhenius parameters of free-radical reactions involving organic compounds.CD3* + C3H6 + CD3H + C3H5* Photolysis of (CD3),C0 + cyclicCH,.+ (CH3*CO)20 + CH, + CH,*C0.0*OC*CH2. Photolysis of (CH,-CO),OCH3. + CH,.CONH, --+ CHI + *CH,.CONH,CH,* + RSH --f CHI + RS* (R = Me, Et, Pr', But)} Pyrolysis of CH, and effect of addedCD3* + C,H,, --t CD,H + CSHg. } carbonsPhotolysis of CH,.CO*OCH,Photolysis of (CH,),CO + CH3CONH2Photolysis of (CH,),CO + thiolsCH3. + (CF,),CO --t CF,* + CH,.CO*CF,CH,. + C2HS + C3Hh.Pyrolysis of (CH3)2N2 + (CF,),COPyrolysis of [(CH,),CO], + olefinsPhotolysis of (C2H5),C0 by sector methodIlg-photodecomp. of H, + C2H,CH3* + C2H4 + C,H,*CH,. + C,H, ---t C4H,*CH3.+ CH,=CH*CH=CH2 + C,Hg.2C,H5* + C4H,,CgH5* 3- CIH4 + CIH,.CF3. + CHd + CF3H + CH3*CF3* + (CHJSCH --.) CF3H + (CH3)3C*CF,* + CH,*CHO --t CF,H + CH,*CO*Photolysis of CF,CHO + additives t JCH,O* + CH,C0.0CH3 -% CH,*OH + *CH,*CO.OCH, Photolysis of CH,.CO.OCH,CH,S* + CH,.CHO --t CH,*SH + CH,.CO* Photolysis of CH,.CHO + CH,SHC,H,.CO. + C,H,* + CO Photo-oxidation of (C,H5) ,CO2C,C14H* + inertPyrolysis of Zn(CH,), + C,H5*CH3,CI. + CH,CI*O.COCI + HCI + *CHCI-OCOCINa- + CH,CI --+ NaCl + CH,.Na. + CFH,CI + NaCl + CFH2*Na. + CF,HCI -+ NaCl + CF,H*Na. + CF,CI + NaCl + CF,.(CH,),CO*OC(CH,), + 2(CH,),CO*Zn(CHJ2 + ZnCH,. + CH,.ZnCH,* + Zn + CH,.(a) Pyrolysis of Cd(CH,), + C,H,-flow Cd(CHJZ --.) CdCH,. + CH,*( b ) Pyrolysis of Cd (CH,) 2, staticCdCH,* + Cd* + CHS*Photochlorination of C,C13H by thesector methodPhotochlorination of CH,Cl.O*COCl I Cl2 + C2CI,H* ---+c C2CIsH + CISNa flame} Pyrolysis of [CH,),CO], + NOI(CHJ3CO.--t (CHJ2CO + CH,.Hg(CHJ2 + HgCHs* + CH3* } Pyrolysis Hg(CH,), + C,H,CH,,{HgCH,* + Hg. + CH,.* C y c l i c s y s t e m s a r e s h o w n i n i t a l i c KINETICS OF CHEMICAL CHANGE. 37a ring structure (I). Dean and Marcus G5 have measured the relative ratesof the rapid bimolecular association between amines and boron trifluorideby means of a steady-state flow apparatus.New or revised values of the kinetics of various free-radical reactionshave been determined during the last year. These are summarised inTable 2.It will be realised that the values in Table 2 depend on the correctidentification of the elementary reactions taking place in the systems studiedand often on the assumption of values of the Arrhenius factors for otherreactions, e.g., 2CH3- C2H6, but for details the original papers should beconsulted.However, further discussion of some of the work listed aboveis desirable.Engel, Combe, Letort, and Niclause g7 investigated the pyrolysis ofpropane and pt- and iso-butane as well as of Pteopentane in the absence of eventraces of oxygen. The activation energy of hydrogen abstraction bytrideuteromethyl from cyclopropane is much larger than previouslyreported.68 At 375" c in McNesby and Gordon's system 68 cyclopropylradicals isomerise to prop-2-enyl, which do not abstract hydrogen readilybelow 500" c.57 In the photolysis of acetic anhydride Ausloos 70 found thatthere appeared to be an equal probability of an initial split to give acetoxyland acetyl radicals and a unimolecular decomposition giving formaldehydeand acetic acid.The yields of carbon monoxide and dioxide from thephotolysis of propionic anhydride showed that both propionyl and propionyl-oxyl decompose readily. The photolysis of acetamide alone was alsoinvestigated. 71 The primary step was either CH,*CO*NH2 __t CH,* +CO-NH, or CH3*CN + H20. The velocity constant for the reaction of themethyl radical with thiols increases as the hydrocarbon radical increases insize.72 Dodd and Smith 77 found that the dimerisation of trifluoromethyl rad-icals from the photolysis of trifluoroacetaldehyde was independent of pressuredown to 0.5 mm.The catalytic effect of thiols on the photodecompositionof acetaldehyde increased in the order H2S > MeSH > EtSH > PriSH >B u ~ S H . ~ ~ In the photo-oxidation of acetone the yield of carbon monoxideis very small at high oxygen pressures, indicating that none is formed byreaction of propionyl with oxygen.79 The collision yield for the reactionC2H5* + 02- C,H50,* was calculated to be It is suggested,however, that the ethylperoxy-radical, C2H502, does not form acetaldehydeplus hydroxyl or ethyl hydroperoxide under these conditions. The chains6 5 J. Dean and R. A. Marcus, J . Chem. Phys., 1957, 26, 162.6 6 P. S. Shaiitarovich and B. V. Pavlov, Zhur.fiz. Khim., 1956, 50, 811.b7 J. Engel, A. Combe, M. Letort, and M. Niclause, Compt. rend., 1957, 244, 453.68 J. R. McNesby and A. S. Gordon, J . Amer. Chem. SOL, 1957, 79, 825.69 M. H. J. Wijnen, J . Chem. Plzys., 1957, 27, 710.70 P. Ausloos, Canad. J . Chem., 1956, 34, 1709.71 B. C. Spa11 and E. W. B. Steacie, Proc. Roy. SOL, 1957, A, 239, 1.72 J . A. Kerr and A. F. Trotman-Dickenson, J., 1957, 3322.73 G. 0. Pritchard and E. W. R. Steacie, Canad. J . Chem., 1957, 35, 1216.74 L. C. Landers and D. H. Volman, J . Amer. Chem. Soc., 1957, 79, 2996.75 A. Shepp and K. 0. Kutschke, J . Chem. Phys., 1957, 26, 1020.76 J. A. Pinder and D. J. LeRoy, Canad. J . Chern., 1957, 35, 588.77 R. E. Dodd and J. W. Smith, J., 1957, 1465.7 8 R. N. Birrell, R.F. Smith, A. F. Trotman-Dickenson, and H. Wilkie, ibid., p. 2807.7@ J. E. Jolley, J . Amer. Chem. SOC., 1957, 79, 153738 GENERAL AND PHYSICAL CHEMISTRY.in the photochlorination of chloromethyl chloroformate apparentlyterminate by a first- or a second-order process.81 The results of Belgianworkers on the photochlorination of chloroform and chloroethylenes havebeen summarised.88 They have developed a general reaction scheme andbeen able to derive much quantitative kinetic data on various elementaryprocesses involving chlorine atoms and chlorine-containing radicals, whichare too extensive to include in Table 2. From the effect of nitric oxide onthe decomposition of tert.-butyl peroxide Birss, Danby, and Hinshelwood 83calculate that the steric factor for the association of methyl with nitric oxideis about 7 x lo5 times less than that for the association of two methylradicals to form ethane.Much work has been published on organic systems in which no quantit-ative kinetics of individual steps has been deduced.The pyrolysis ofmethane at 1000" c in a silica tube is a homogeneous first-order reacti0n.8~Parsons, Danby, and Hinshelwood consider that ethane may decomposein two ways: (1) C2H6 + C,H, + H, or (2) C2H6 __t CH, + CH,, theCH,: radicals giving the other products. The rate of reaction (1) is reducedto a limit by the addition of nitric oxide, and the effect of sulphur hexa-fluoride on the forward and back reactions leaves the equilibrium constantunchanged. The decomposition is initiated at 368" c by azomethaneMe,N,,Q1 and the reaction of oxygen atoms, from the photolysis of nitrousoxide, with ethane is more rapid than with nitrous oxide it~elf.9~ At highpressures, 400-2000 atm., the rate of polymerisation of ethylene dependson high powers of the pressure, but if fugacities are used the kineticexpressions are compatible with the usual free-radical chain mechanism.93The polymerisation of acetylene below 550" c in a static system is reportedto give reproducible second-order velocity constants, the overall activationenergy being 46.7 & 2 k~al./mole.~~ Silcocks 95 has also studied the thermalreactions at 352-472"~ in a static system.He finds that homogeneoussecond-order polymerisation occurs, k = 3-72 x 1013 exp (-60,20O/RT)cm.3 mole-1 sec.-l, combined with a surface reaction.The mercury-photosensitised decomposition of allene and buta-1 : 2- and -1 : 3-diene,968 0 F. S. Dainton, D. A. Lomax, and M. Weston, Trans. Faraday SOC., 1957, 53, 460.81 M. J. Dignam, W. G. Forbes, and D. J. LeRoy, Canad. J . Chem., 1957, 35, 1341.82 J. F. Reed and B. S. Rabinovitch, J . Phys. Chem., 1957, 61, 598.83 F. W. Birss, C. J. Danby, and (Sir) C. Hinshelwood, Proc. Roy. SOC., 1957, A ,84 S. J. W. Price and A. F. Trotman-Dickenson, Trans. Faraday SOC., 1957,53, 1208.86 Idem, ibid., p. 939.86 C. M. Laurie and L. H. Long, ibid., p. 1431.8 7 J. R. McNesby and A. S. Gordon, J . Amer. Chem. SOC., 1957, 79, 4593.88 M. Ackermann, G. Chiltz, S. Dusoleil, P. Goldfinger, G.Martens, and D. Vander Auwera, Nature, 1957, 179, 731 : G. Chiltz, G. Martens, and A. M. Mahieu, Nature,1957, 180, 1068.89 J. E. Germain and C. Vaniscotte, Bull. SOC. chim. France, 1957, 692.9 0 B. N. Parsons, C. J. Danby, and (Sir) C. Hinshelwood, Proc. Roy. SOC., 1957,91 A. D. Stepukhovich and E. G. Kaplan, Zhur. $2. Khim., 1956, 30, 928.99 G. A. Castellion and W. A. Noyes, J . Amer. Chem. SOC., 1957, 79, 290.93 R. K. Laird, A. G. Morrell, and L. Seed, Discuss. Faraday SOC., 1957, 22. 126.94 G. J. Minkoff, D. M. Newitt, and P. Rutledge, J . Appl. Chem., 1957, '9, 406.95 C. G. Silcocks, Proc. ROY. SOC., 1957, A, 242, 411.96 J. Collin and F. P. Lossing, Canad. J. Chem., 1957, 35, 778.239, 154.A , 240, 333KINETICS OF CHEMICAL CHANGE. 39and the thermal decomposition of isobutene 97 have been investigated.Allenegives C,H,* radicals (probably *CH,--C- CH). The light emission from di-acetylene at 0.5min. subjected to flash photolysis shows C,, C,, and CH bands.23Atkinson and Atkinson 98 studied the kinetics and products of thepyrolysis of systems derived from tetrafluoroethylene at 550-750" c , andTrenwith and Watson 99 that of three chlorofluoromethanes at 400-900" c.Free radicals such as CF,:, CF,., and CF,Cl- have been suggested as inter-mediates. The activation energies of the thermal decomposition ofchloroform and deuterochloroform are identical: 37-2 & 2 and37.5 & 2 kcal./mole respectively.loO An upper limit to the value ofD(CHCl,-Cl) of 72 kcal./mole has been calculated.The reaction of ethylbromide to give ethylene and hydrogen bromide, although of the first orderat 310476" c, is complex.lol The primary step is probably unimolecularwith an activation energy about 52 kcal./mole, followed by a surface reactionof the hydrogen bromide and ethyl bromide giving bromine atoms. Thephotolysis in excess of cyclopentane gives ethane as the main product, inwhich the 12C enrichment was 1.0070 & O-OO08.102 Holmes and Maccoll lo3have reinvestigated the pyrolysis of isopropyl iodide. Above 285" c thereappears to be a unimolecular elimination of hydrogen iodide followed bya rapid reduction of the isopropyl iodide by hydrogen iodide, and below thattemperature a further autocatalysis by the iodine molecules formed.The pyrolysis of rt-butanol at 573-629" c is of the first order,lW k =1012.2 exp (56,70O/RT) sec.-l.The primary step probably gives wpropyland hydroxymethyl radicals. The ratio of ethane to carbon monoxide(ca. 1.25) in the products of the high-intensity flash photolysis of acetonevaries little with the pressure.lo5 There is some evidence for the formationof long-lived excited acetone molecules below 210 mp. Lossing106 hasfollowed the mercury-photosensitised decomposition of acetone andacetaldehyde at room temperature by means of a mass-spectrometer. Theprimary steps are Hg* + (CH,)&O -+ Hg + CH,. + CH,*CO*and Hg* +CH,*CHO _+ Hg + CH,. + CHO., and at least 25% of the acetyl radicalsare sufficiently long-lived to react with another hot mercury radical, Hg*.The effects of carbon dioxide and oxygen on the photolysis of acetone showthat the reactions (1) CH,*CO* + M --+ CH,* + CO + M and (2) CH,.+0, + M - CH3*02 + M occur.1o7 If M is acetone then at 200" c k , =1.6 x 10-31 cm.6 molecule-2 sec.-2. The results of the photolysis of hexa-deuteroacetone in the presence of four butenes show that trideuteromethyl9 7 Yu. I. Liadova, V. I. Vedeneyev, V. V. Voewdsky, Doklady Akad. Nauk, S.S.S.R.,98 B. Atkinson and V. A. Atkinson, J., 1957, 2086.D9 A. B. Trenwith and R. H. Watson, ibid., p. 2368.1957, 114, 1269.100 G. P. Semeluk and R. B. Bernstein, J. Amer. Chem. Soc., 1957, 79, 46.101 A. E. Goldberg and F. Daniels, ibid., p. 1314.102 H. L. Friedman, R. B. Bernstein, and H. E. Gunning, J.Chem. Phys., 1957,103 J . L. Holmes and A. Maccoll, Proc. Chem. Soc., 1957, 175.lo4 J . A. Barnard, Trans. Faruday Soc., 1957, 53, 1423.105 G. K. Oster and R. A. Marcus, J. Chem. Phys., 1957, 27, 472.106 F. P. Lossing, Caxad. J. Chem., 1957, 35, 305.107 D. E. Hoare, Trans. Faruduy Soc., 1957, 53, 791; D. E. Hoare and A. D. Walsh,26, 528.ibid., p. 110240 GENERAL -4ND PHYSICAL CHEMISTRY.radicals may add to each carbon atom of the double bond, the radicalformed often losing a methyl radical, or may abstract an a-hydrogen atom.losThe photolysis of the three branched-chain dibutyl ketones enables the ratioof the rates of disproportionation (1) to dimerisation (2) of butyl radicalsto be determined: KJk, = 4-59 (tert.), 0.418 (iso), and 2.27 (sec.).If the values of k , are equal then the factor determining k , is the number ofavailable hydrogen atoms which can be removed to give a stable olefin.Thepyrolysis of n-butyl methyl ketone at 430-500" c is predominatelyhomogeneous, the apparent activation energy being 52 & 3 kcal./mole.l1°The reaction involves the CH,*CO*C,H,* radical which may decompose invarious ways. The products cf the photolysis of cyclobutanone, cyclo-pentanone, and cyclohexanone at 100--300" c suggest that the initial stepis a split at either the CH2-CO bond or a CH2-CH, bond.ulThe photolysis of keten and mcthyl- and dimethyl-keten under variousconditions has been studied extensively, especially with regard to thereactions of the radicals, e.g., CH,:, p r o d u ~ e d .~ ~ ~ , l l ~ The results at -78"and of the flash photolysis indicate that the reaction of methylenewith keten is very 25a Added oxygen mainly deactivatesexcited keten (CH,:CO) molecules at room temperature.l12c Kistiakowskyand Mahan 112d suggest that vibrationally excited ethylidene radicalsCH,*CH: are produced from methylketen and rearrange at measurable ratesinto ethylene. Propene and carbon monoxide are the major productsfrom dimethylketen, probably via (CH,),C=C=O __t CO + (CH,),C: +C3HB.112e Methylene radicals appear to react with paraffins to give onlythe next higher member of the series.l12f With ethylene and propene orcyclopropane a t very low pressures, mainly propene and butanes respectivelyare fonned.112g~h As the pressure is increased the yield of cyclopropane andmethylcyclopropane respectively increases.The energy-rich moleculesfornied by addition of methylene either deactivate on collision orisomerise, e.g.,MCH2 + C,H,--t CH,-CH2* - + CH,-CH, CH,CH-CH* 'd (11) '\ / ';< h 2 = C H . C H , CH,Okabe and Noyes113 describe a technique for measuring the relativeintensities of the blue fluorescence and green phosphorescence of diacetyl,(MeCO),. The ratio green : blue at 26" c/42 mm. is 58 8. It decreasesas the temperature is raised, and falls rapidly to zero as oxygen is added.Cvetanovic and Doyle 114 have studied the mercury-photosensitisedlo8 J. R. McNesby and A. S. Gordon, J . Amev. Chem. SOC., 1957, 79, 5902.lo9 J. W. Kraus and J. G. Calvert, ibid., p.5921.111 F. E. Blacet and A. Miller, ibid., p. 4327.112 ( a ) G. B. Porter, ibid., p. 827; ( b ) W. G. Paterson and H. Gesser, Canad. J .Chem., 1957, 35, 1137; (G) G. B. Porter, J . Amer. Chem. SOL, 1957, 79, 1878; ( d )G. B. Kistiakowsky and B. H. Mahan, ibid., p. 2412; (e) R. A. Holroyd and F. E.Biacet, ibid., p. 4830; (f) J. H. Knox and A. F. Trotman-Dickenson, Chem. and Ind.,1957, 731; (g) H. M. Frey, J . Amer. Chem. SOL, 1957, 79, 1259; ( h ) J. H. Knox andA. F. Trotman-Dickenson, Chem and Ind., 1957, 1039.113 H. Okabe and W. A. Noyes, J . Amer. Chem. Scc., 1957, 79, 801.114 R. J. Cvetanovic and L. C. Doyle, Caszad. J . Chesn., 1957, 35, 605.W. T. Barry and W. D. Walters, ibid., p. 2102KINETICS OF CHEMICAL CHANGE. 41decomposition of 2 : 3-epoxybutane at 25" c.They suggest that methyl andepoxypropyl (11) radicals are formed in the primary step. The kinetics andproducts of the reaction of acetaldehyde with nitrogen dioxide at 110-180" have been in~estigated.11~ A mechanism is suggested involving acetyland methyl radicals. The decompositions of propyl nitrite and butyl nitritein a static system are of the first order, the overall activation energies being34-7 and 26.2 kcal./mole respectively.l16In conclusion some work on gas-phase oxidation systems will be brieflymentioned. An extensive investigation of the slow combustion of methaneat 460-520" c has been reported by Egerton, Minkoff, and Sa10oja.l~~Considerable quantities of hydrogen peroxide are formed as one inter-mediate (the other being formaldehyde), provided that the surface of thevessel has been treated with acid.It appears to undergo a homogeneoussplit leading to branching (see ref. 29). The oxidation of n-heptane in aflow system a t 300" c gives a mixture of aldehydes, and the products from[l-2H]propane and [2-2H]propane with a small amount of oxygen show thatat 360420" c the attack at a secondary carbon-hydrogen bond is 1.9 timesfaster than attack at a primary one.118 The slow combustion of methanoland ethanol has been studied.ll9 Delayed branching is due to formaldehydeand acetaldehyde with the former and the latter respectively. The effect ofethane on the first limit of the hydrogen-oxygen reaction at 540" c invessels coated with potassium chloride suggests that hydrogen atoms arereplaced by HO,.radicals by the steps H* + C2H, _t H, + C2H5* andC2H5* j- 0, _t C2H, + H0,*.120 The rate of formation of acetic acid inthe oxidation of ethane catalysed by hydrogen bromide increases withincrease in hydrogen bromide concentration but does not depend on theethane or oxygen concentrations.121 The kinetics of the mercury-photo-sensitised oxidation of ethane show that the formation of ethylhydroperoxide, the primary product, is probably not a free-radical chainreaction .lZ2haspublished an important series of papers on the theory of electron-transferreactions. In the first is presented a method of calculating the free energyof reorganisation of the solvent molecules around the reactants before theelectronic jump, and from this is developed a quantitative theory of electron-transfer reactions. In such reactions only a slight overlap of the electronicReactions in Solution.-During the past year, R.A. Marcus 1s 2 s115 A. E. Pedlar and F. H. Pollard, Trans. Faraday Soc., 1957, 53, 44.116 M. F. Nagiev, 2. G. Petrova, and A. I. Sultanova, Doklady Akad. Nauk, S.S.S.R.,117 (Sir) A. Egerton, G. J. Minkoff, and K. C. Salooja, Proc. Roy. Soc., 1956, A ,118 R. Burt, F. B. Ebeid, and G. J. Minkoff, Nature, 1957, 180, 188.119 K. M. Bell and C. F. H. Tipper, Yroc. Boy. Soc., 1956, A , 238, 256; Trans.Faraday Soc., 1957, 53, 892; C. F. Cullis and E. J. Newitt, Proc. Roy. Soc., 1956, A ,237, 530; 1957, A , 242, 516.l20 R. R. Baldwin and R. F.Simmons, Trans. Favaduy Soc., 1957, 55, 955, 964.121 M. F. Sedova and N. M. Emanuel, Izvest. Akad. Nauk, S.S.S.R., Otdel Khitn.122 J. S . Watson and B. de B. Danvent, J . Phys. Chem., 1957, 61, 577.1956, 109, 573.235. 158; Combustion and Flame, 1957, 1, 25.N a u k , 1956, 658.R. A. Marcus, J . Chem. Phys., 1956, 24, 966.2 Idem, ibid., 1957, 26, 867.3 Idem, ibid., p. 87242 GENERAL AND PHYSICAL CHEMISTRY.orbitals of the reacting molecules is to be expected. In most reactionsthere is usually a transfer of atoms or groups of atoms between the reactantsand one would expect a considerable spatial overlap of the electronic orbitalsof the reacting molecules in the transition complex. The assumption ofslight overlap is shown to lead to a reaction path which involves an inter-mediate state X * in which the electrical polarisation of the solvent doesnot have an equilibrium value.This state X * can either re-form thereactants or, by electron transfer, form a state X in which the ions arecharacteristic of the products. Free energies and entropies of activationof some inorganic electron-exchange reactioiis have been calculated fromthe theory without the use of adjustable parameters. It is suggested thatreactions like that of ferrous ion with FeC12+, which probably has an atom-transfer mechanism, should be studied in deuterium oxide because theabsence of an isotope effect would be expected if chlorine-atom transferoccurs (unless the O-H vibration frequencies in the hydration shells changeappreciably when the activated complex forms).Free energies and entropiesof activation have been calculated for some organic redox reactions.It has been shown that the application of differential thermal analysisto reaction kinetics can provide the frequency factor, the activation energy,and the heat of reaction from a single rapid measurement.* A generalequation has been derived for the kinetics of complex isotopic exchangereactions in which each of three non-equivalent species is exchanging withthe otherThese formpart of an extensive review by Stranks and Wilkirx6 Hudis and Dodson 7have concluded that the isotopic exchange between iron@) and iron(m) isbrought about by hydrogen-atom transfer since the reaction rate is reducedwhen deuterium is substituted for hydrogen.These findings have beenconfirmed by a recent study of the neptunium(v)-neptunium(v1) exchangein both water and deuterium oxide.8 It was also demonstrated thatthe rate is unaffected by substitution for sodium by magnesium or lanthanumperchlorates, even at ionic strengths as high as 3M.Interest has increased in the effect of anions on mechanisms of inorganicreactions as illustrated by the investigations of Brubaker and his co-workerson the thallium(1)-thallium(m) reaction.g* lo In 2-19~-sulphuric acidexchange is about 200 times as fast as in perchlorate solutions of the sameacidity and ionic strength, the mechanism beingElectron-exchange reactions between ions of the same metal.*TIsf + TISO,- __t TI3+ + *TISO,-*TISO,+ + TI(SO,J,S- __t TISO$ + *TI(S0,J23-*TI(SO&- + TISO,- d TI(SO,J,- + *TISO,-Steps having reactants with opposite charges were preferred but it isnow becoming apparent that coulombic forces are not necessarily significant4 H.J . Borchardt and F. Daniels, J. Amer. Chem. SOC., 1957, 79, 41.6 D. F. Abell, N. A. Bonner, and W. Goishi, J . Chem. Phys., 1957, 27, 658.6 D. R. Stranks and R. G. Wilkins, Chem. Rev., 1957, 57, 743.7 J. Hudis and R. W. Dodson, J. Amer. Chem. Soc., 1956, 78, 911.8 J. C. Sullivan, D. Cohen, and J . C. Hindman, ibid., 1957, 79, 3672. * C. H. Brubaker and J . P. Mickel, J. Inorg. Nuclear Chem., 1957, 4, 55.10 C. H. Brubaker, K. 0. Groves, J. P. Mickel, and C. P. Knop, J. Amer. Chem. Soc.,1957, 79, 4641KINETICS O F CHEMICAL CHANGE.43in such reactions. The addition of chloride ions to the system causes therate to pass through a minimum (as was found earlier by Harbottle andDodson 11 who used perchlorate media) : the initial decrease was attributedto the failure of T1Cl2+ and TlCl,+ to exchange appreciably with thallium(1)whereas the increase at higher [Cl-] : TlIII ratios is believed to be due torapid exchange between TlC1,- and thallium@) chloride complexes. It isnoteworthy that the most rapid exchange occurs when both the valencystates of thallium are carrying the same sign of charge. The effect ofanions on another well-established exchange reaction has been studied,namely the influence of thiocyanate on the exchange between ferrous andferric iron.12 Four reaction paths appear to be available, i.e., Fe2+ canexchange with FeSCN2+, Fe(SCN),+, Fe3+, or FeOH2+; these paths andthe energies associated with them are similar to those found for the additionof chloride13 or fluoride14 ions.In perchlorate media at an ionic strength of 2 .0 ~ the isotopic exchangebetween plutonium(II1) and plutonium(1v) was l5 100 to 1000 times as fastas the ferrous-ferric reaction so that concentrations in the range l O - 5 ~ to10-GM had to be used. The two reaction paths Pu3+ + Pu4+ and PIP+ +PuOH3+ accounted for the kinetics.Sulphate complexes dominate the mechanisms of both the forward andthe reverse reaction of the equilibrium NplV + NpVI =F+ 2NpV whichhas been investigated in sulphate media.16The cerium(In)-cerium(Iv) reaction in 6.0~-perchlorate has been found tobe of the second order in cerium(Iv), the dependence on hydrogen ion concen-tration being complex; exchange between CeIII and the species Ce(OH),2+,Ce(OH),+, and CeOCeOH5+ accounts for these facts.17The exchange of 54Mn between MnO,,- and Mn0,- in O.lG~-sodiumhydroxide has a specific rate constant of 710 1.mole-l sec.-l at 0"c and anoverall activation energy of 10.5 kcal. mole-l.18The rate of the neptunium(v)-neptunium(v1) exchange in perchloricacid is not affected by the variation of the macroscopic dielectric constantbrought about by the addition of ethylene glycol or sucrose.19 It appearsthat non-electrostatic forces dominate the energetics, i.e., the exchangemay proceed by transfer of an atom.Many systems have been studied having water as solvent and nowattention is being turned to other solvents; an example is the exchangereaction between stannic and stannous chlorides in pure methanol.20Magnetic resonance holds out a meansof determining rates of very fast reactions in this class.One of the firstto be studied is the electron exchange between neutral molecules andOther electron-exchange reactions.l 1 G. Harbottle and R. W. Dodson, J . Amer. Chem. SOC., 1951, 73, 2442.1% G. S. Laurence, Trans. Faraday SOC., 1957, 53, 1326.I 3 J. Silverman and R. W. Dodson, J . Phys. Chem., 1952, 56, 846.14 J. Hudis and A. C. Wahl, J . Amer. Ckem. SOC., 1953, 75, 4153.1 5 T. K. Keenan, J . Phys. Chem., 1957, 61, 1117.16 J.C. Sullivan, D. Cohen, and J. C. Hindman, J . Amer. Chem. SOC., 1957, 79, 4029.17 F. R. Duke and F. R. Parchen, ibid., 1956, 78, 1540.18 J. C. Sheppard and A. C . Wahl, ibid., 1957, 79, 1020.1 9 D. Cohen. J. C. Sullivan, E. S. Amis, and J. C. Hindman, ibid., 1956, 78, 1543.2 0 E. G. Meyer and M. A. Melnick, J . Phys. Chem., 1957, 01, 367p4 GENERAL AND PHYSICAL CHEMISTRY.positive ions of tetra-N-methyl-j5-phenylenediamine by observing thedependence on concentration of the width of the lines of the absorptionband due to proton (lH) resonance.21 The method is applicable tosystems having rate constants greater than 3 x lo3 1. mole-1 sec.-l. Oneof the largest rate constants yet measured, 0.5 x lo8 1. mole-1 sec-1, hasbeen obtained for the cuprous-cupric reaction in hydrochloric acid,22 thenuclear magnetic resonance line width of 63Cu being used.McConnell andBerger 23 have developed a theory for these reactions and have called them" paramagnetic pulse " reactions from the condition that exchange betweenparamagnetic and diamagnetic species results in a change in a large hyperfinemagnetic field acting at one or more of the molecular nuclei. Bloch'sequations 24 were used to establish a quantitative relation between theshape of the nuclear resonance line, nuclear and electron relaxation times,and the reaction rate.Also, variations in line width of electron spin resonance absorptionbands are being used to measure rates of electron exchange between thecomponents of organic redox systems.An example is the broadening ofthe electron spin resonance lines of naphthalene negative ion caused by thepresence of naphthalene; 25 the bimolecular rate constants lie in the range107-109 1. mole-l sec.-l and vary with the solvent and with the alkali-metal ion used.Other isotopic exchange reactioszs. Inorganic reactions in this group havebeen reviewed.6The rates of exchange of ammonia between the solvent liquid ammoniaand ligand ammonia for five metal-ammine cations have been measuredby using nitrogen-15.26 The observed slow exchange for Cr(NH3),3+ andCo(NH3),3+, as compared with the rapid exchanges for Ag(NHJ2+,Cu(NH3),2+, and Ni(NHJe2+, is consistent with their classification as inertinner-orbital complexes.The effect of light on the rate of substitution of H,180 into Cr(H20),3+has been studied at the wavelengths of the three absorption bands of thechromic ion? Reaction probably occurs from an excited electronic staterather than from an excited vibrational state.The formation constants of the ions PtBr,2- and PtBrC2- do not determinethe rate of exchange of radiobromine with ligand bromine.28Iodine-131 being used, isotopic exchange reactions of iodine cyanidewith I- and and iodine chloride with 1230 have been shown to be veryrapid; the mechanism is thought to include molecular association, e.g.,rci + *I, ___L 1(*r2)c1 *IC~ + "11.21 C.R. Bruce, R. E. Norberg, and S. I. Weissman, J . Chem. Phys., 1956, 24, 473.22 H. M. McConnell and H. E. Weaver, ibid., 1956, 25, 307.23 H.M. McConnell and S. B. Berger, ibid., 1957, 27, 230.24 F. Bloch, Phys. Rev., 1946, 70, 460.25 R. L. Ward and S. I. Weissman, J . Amer. Chem. Soc., 1957, 79, 2086.26 H. U. D. Wiesendanger, W. H. Jones, and C . S. Garner, J . Chem. Phys., 1957,27 R. A. Plane and J . P. Hunt, J . Amer. Chem. Soc., 1957, '49, 3343.28 A. A. Grinberg and G. A. Shagisultanova, Izvest. Akad. Nauk S.S.S.R., Otdel.2s F. E. Jenkins and G. M. Harris, J . Phys. Chem., 1957, 61, 249.30 V. L. Pavlov and Yu. Ya. Fialkov, Zhur. obshchei Khim., 1956, 26, 1531.27, 668.khim. Nauk, 1955, 981KINETICS OF CHEMICAL CHANGE. 45The exchange of oxygen-18 between water and sulphuric acid 31 and withsec.-butyl alcohol32 has been studied. In the former system the rate-determining step is the decomposition of sulphuric acid into water andsulphur trioxide and in the latter the slow step is heterolysis of the oxoniumion ROH,+.Formation of benzoyl radicals appears to be essential to the exchangeof carbon-14 between benzoyl peroxide and potassium benzoate in acetone-water mixtures.33 With water as solvent, no significant exchange occurredfor sulphur-35 between sulphate ion and peroxymonosulphuric acid or forcarbon-14 between acetate and peroxyacetic acid and between benzoateand peroxybenzoic acid.=Use of solvents having different dielectric constants affects the rate ofthe ion-dipole reaction of transfer of radioactive iodine between methyliodide and sodium iodide.35Treatment of alkanes with deuterium-labelled sulphuric acid at roomtemperature showed that hydrocarbons with tertiary carbon atoms arecapable of exchange whereas others are n0t.~6 For the exchange of thearylthio-group between ditolyl sulphide and thiocresol in xylene, andbetween dibenzyl sulphide and toluene-a-thiol in decalin, it is believed thatthe activation energy depends upon the dissociation energy of the sulphur-sulphur bond.37Rates of exchange of benzoyl iodide and bromide with elementaryiodine and bromine, respectively, in nonpolar solvents have been measured.38The exchange of isotopically labelled phosphorus and chlorine betweenphosphorus tri- and penta-chloride in carbon tetrachloride has been shownto occur by the mechanism 39 PCl, & PCl, + Cl,.EZectyon exchange between ions of dzflerent metals.These reactions dependmarkedly on the type of anion present, for example, Uvl and FeII areformed from UIV and FeIII in sulphuric acid but the addition of phosphatesbrings about complete reversal.40 This result is consistent with the moreextensive complex-formation by phosphoric acid expected for the ionsU4+ and Fe3+ than for U022+ and Fe2+. Effects of anions are not normallyso spectacular but nevertheless can determine the main reaction path.A detailed study of the reaction between cobaltic ions and cerous ions inperchlorate media led to the conclusion that the rate-determining step isthe reaction of CeC1042+ with CoOH2+; the true activation energy and theentropy of activation were found to be 19 kcal. mole-l and 14 cal. mole-ldeg.-l re~pectively.~~ The cobalt(1n)-thallium(1) reaction has also been31 T.C. Hoering and J. W. Kennedy, J . Amer. Chem. Soc., 1957, 79, 56.33 C. A. Bunton and D. R. Llewellyn, J., 1957, 3402.33 G. Giacometti and A. Iliceto, Biccrca Sci., 1957, 27, 743.3 p G. Levey, D. R. CampbA1, J. 0. Edwards, and J. Maclachlan, J . Amel,. Clcein. Soc.,1957, 79, 1797.35 E. R. Swart and L. J. le Rous, J . , 1957, 406.36 V. N. Setkina, D. N. Kursanov, 0. D. Sterligov, and A. L. Liberman, ProblemyMekhaizizma G Y ~ . Reactsii, Acad. Nauk Ukvain S.S.R., 0tdel.jiz.mat. khim. Nauk, 1953,199.37 E. N. Gur’yanova and V. N. Visil’eva, Zhur.$z. Khim., 1955, 29, 576.38 A. Goldman and R. M. Noyes. J . Amer. Chenz. SOC., 1957, 79, 5370.39 W. E. Becker and R. E. Johnson, ibid., 1957, 79, 5157.4 0 C.F. Baes, J . Phys. Chenz., 1956, 60, 805.41 L. H. Sutcliffe and J. R. Weber, Trans. Faraday SOC., 1956, 52, 122646 GENERAL AND PHYSICAL CHEMISTRY.studied in perchloric acid and is accelerated by the addition of sulphateions.42Kinetic data from the reduction of thallium(II1) by trisdipyridyl-osmium(I1) in perchlorate solutions 43 were interpreted as implying thatT13+ and T10H2+ react with O~(dipy),~+. Chloride ions produce a similareffect to that observed in the thallium(I)-thallium(m) exchange l1 andthe reduction of thallium(II1) by iron(rI).44 A study of the oxidation ofmercury(1) by thallium(II1) in aqueous solution 459 46 led to the postulationthat the slow step is a two-electron transfer between a mercury atom,formed by dismutation of HgZ2+, and a hydrolysed thallic ion; recentlya value of 5-5 x a t 25" has been obtained for the dismutation constantby use of a radioactive tracer te~hnique.~' Formation of complex ionsagain affects the rate; perchlorate ions retard the reaction probably byforming complexes with Hg,2+, whereas complexes between mercuric ionand chloride or bromide ions accelerate the reaction.Kinetic measurements on the system Cr2+ + (NH,),Co(H,0)3+ accom-panied by tracer experiments on the transfer of oxygen show that hydroxylion and probably water are transferred during the reaction.48 It issuggested that this mechanism is a distinct possibility for other aquo-cations undergoing electron transfer.All the reactions quoted in this group have had water as solvent butsome preliminary results have been reported for the systems plumbic withcobaltous, ceric, or manganous ions in acetic acid.4gHomogeneous catalysed reactions.An excellent Review by Halpern 50describes the reactions undergone by molecular hydrogen in solution whenactivated catalytically by metal salts. For the catalysis by cupric saltsin quinoline solution it has been suggested that CuH+ is the active inter-mediate. 51 The catalysis of the homogeneous reduction of pennanganateby hydrogen in aqueous solution is thought to have AgH+ and MnO,,- asintermediates ; 52 however, when dichromate ions are reduced under similarconditions 53 two independent reaction paths appear having the slow steps2Ag+ + H, + 2AgH+ and Ag+ + H, @ AgH + H+.Bawn and his co-workers have continued their work on oxidations oforganic compounds catalysed by metal salts with an investigation of theautoxidation of benzaldehyde in the presence of cobaltous acetate andthe autoxidation of acetaldehyde in the presence of manganous, cupric,and cobaltous all in acetic acid.A similar study has been made42 K. G. Ashurst and W. C. E. Higginson, J . , 1956, 343.43 D. H. Irvine, J., 1957, 1841.44 F. R. Duke and B. Bornong, J. Phys. Chem., 1956, 60, 1015.4 5 A. M. Armstrong, J. Halpern, and W. C. E. Higginson, ibid., p. 1661.413 A. M. Armstrong and J . Halpern, Canad. J. Chem., 1957, 35, 1020.4' H. C. Moser and A. F. Voigt, J. Amer. Chem. Soc., 1957, 79, 1837.4 8 R. K. Murmann, H.Taube, and F. A. Posey, ibid., p. 262.49 L. H. Sutcliffe and J . Walkley, Nature, 1956, 178, 999.5 0 J. Halpern, Quart. Rev., 1956, 10, 463.5L J. Halpern, E. R. Macgregor, and E. Peters, J. Phys. Chem., 1956, 66, 1455.52 A. H. Webster and J . Halpern, Trans. Faraday Soc., 1956, 53, 51.53 Idem, J . Phys. Chem., 1957, 61, 1239.54 C. E. H. Bawn and J. E. Jolley, Proc. Roy. Soc., 1956, A , 237, 293.5j C. E. H. Bawn, T. P. Hobin, and L. Raphael, ibid., p. 313KINETICS OF CHEMICAL CHANGE. 47of the oxidation of liquid cyclohexene catalysed by salts of iron, cobalt,manganese, and copper.56 Reaction between the catalyst and cyclohexenylhydroperoxide to form a complex is the initiation process but in some casesa simultaneous initiation reaction between the catalyst and cyclohexeneis possible.New complexes formed by chelating agents were found to havedifferent catalytic a~tivities.~’ The elimination of catalyst after initiationof oxidation of decane by manganese and cobalt laurates and stearatesdoes not lower the reaction rate.58 Formation of cuprous ions was detectedin the cupric-ion catalysed oxidation in aqueous organic solvents of somehydroxylic organic compounds, e.g., ascorbic acid and quinol, by theretardation caused by the addition of the cuprous complex-forming agent,cuproin. 59It has been deduced from the kinetics of the liquid-phase oxidation ofhydrocarbons that tetraethyl-lead reacts with the peroxides formed.60, 61Changes in redox potentials have been used.to follow the catalyticdecomposition of peroxydisulphuric acid, the most rapid reaction being theformation of H2S0,.62 The effectiveness of silver(1) and copper(I1) isattributed to the formation of higher-valency states.Kinetic data for the curtailment of the activity of sodium molybdatein the catalytic decomposition of hydrogen peroxide by calcium salts havebeen supported by the isolation of two calcium permolybdates.63Cobaltic hydroxide is much more effective than nickelic hydroxide indecomposing sodium hypochlorite in alkaline solution. 64The observed chemical reaction in the photolysis of ceric ion-thallousion mixtures is the oxidation of thallous by ceric The kinetic datacan be interpreted by a mechanism in which thallous ion competes withcerous ion for hydroxyl radicals.This conclusion is supported by resultsfrom the radiolysis of the mixtures with 6oCo radiation.66Other renctiom of oxygen and peroxy-compounds. The reactions ofoxygen with iron(I1) G7 and with plutonium(II1) 68 in sulphuric acid havebeen shown to depend on the sulphate-ion concentration. From theeffect of deuterium oxide on the latter system 69 it has been postulatedthat the transition state is two plutonium(II1) sulphate complexes linkedby an oxygen bridge, ie., transfer of a hydrogen atom is the main process.A chain mechanism is indicated for the autoxidation of liquid 1 : 4-di-methylcyclohexane. The parent hydrocarbon being used as solvent, the6 6 A. J. Chalk and J. F. Smith, Trans. Faruduy SOC., 1957, 53, 1214.5 7 Idem, ibid., p.1235.5 8 D. G. Korre, 2. K. Maims, and N. M. Emanuel’, Zhur. $2. h’him., 1955, 29, 710.5 9 R. Flitman and E. Frieden, J . Amer. Chem. SOL, 1957, 79, 5198.6 O G. S. Shimonaev and I. V. Rozhkov, 2hur.fiz. Khim., 1955, 29, 791.61 Idem, ibid., 1957, 31, 94.6a H. Galiba, L. J . CSanyi, and 2. G. Szab6, 2. anorg. Chem., 1956, 287, 152.63 G. A. Bogdanov, T. I. Berlrengeim, and.V. A. Shcherbinin, 2huv.jiz. Khim., 1956,64 F. M. Perel’man and A. Ya. Zvorykin, ibid., 1955, 29, 980.6 5 T. J. Sworski, J . Amer. Chenz. SOC., 1957, 79, 3655.6 6 Idem, Radiation Research, 1956, 77, 483.67 R. E. Huffman and N. Davidson, J . Amer. Chew SOC., 1956, 78, 4836.6 8 T. TV. Newton and F. B. Baker, J . Phys. Chem., 1956, 60, 1417.6 9 Idem, ibid., 1957, 61, 381.7 0 V.Stannett, A. E. Woodward, and R. T3. Mesrobian, ibid., 1957, 61, 360.30, 88948 GENERAL AND PHYSICAL CHEMISTRY.decomposition of the peroxide derived from it was found to be of the secondorder in peroxide; this is thought to be due to the occurrence of peroxidedimers. The intermediate peroxide formed in the oxidation of decane wasfound to break down to give alcohols and carbonyl compounds as theprincipal products.71 That acids are not formed directly in the productsof the decomposition of the peroxide is supported by the kinetics. At 120"liquid 2 : 5-dimethylhexane and 2 : 4-dimethylpentane gave the corre-sponding peroxides in high yield even though only 10% reaction wasachieved. 72 The results show that intramolecular attack of peroxy-radicalsis highly efficient at the position, somewhat less so at the y position, andof little significance at the o! or the 6 position.The efficiency of intra-molecular oxidation appears to be favoured by attachment of the peroxy-radical to a tertiary carbon atom.Interest in the reactions of hydrogen peroxide with ferrous ion continues ;a fine piece of experimental work by Dainton and Hardwick 73 was directeda t determining the ratio of the rate constant of the reactions of hydroxylradicals with solute (dissolved hydrogen or carbon dioxide) to the rateconstant for the reaction of ferrous ions with hydroxyl radicals. In afurther study of this system, Hardwick 74 has found k,/k, to be 0.116 at20.2" for O.1M-perchloric acid, for the reactions H, + OH __f H,O + H(k,)and Fe2+ + OH __t Fe3+ + OH-(K,). The rate constants 5.3 x lo8exp (-9450/RT) 1.mole-l sec.-l in 1.00M-perchloric acid and 9-6 x losexp (-9750/RT) 1. mole-l secrl in 0-8~-sulphuric acid have been evaluated 75for the reaction between ferrous ions and hydrogen peroxide. The differ-ences between results of previous workers are explained. When glycineis present the course of the reaction is determined by competition betweenferrous ion and glycine for the hydroxyl radi~al.7~ The overall rate ofthe reaction is controlled by the rate of production of the hydroxylradical which in turn depends upon the concentrations of glycine andhydrogen ion.In the reduction of cobaltic perchlorate by hydrogen peroxide 77 evidencewas obtained for the occurrence of the species Co111H02- and its formationconstant was estimated .The appearance of the H02* radical in the decomposition of hydrogenperoxide catalysed by cupric, ferrous, and cobaltous ions has been detectedby means of 2 : 6-di-te~t.-butyl-4-methylphenol, which gives a crystallineproduct.78Radiosulphur has been used in an investigation of the sulphite-per-sulphate reaction;. it was demonstrated that a quarter of the sulphur inthe dithionate produced originated from the per~ulphate.~~ This led to7 1 L. S. Vartanyan, Z. K.Mauzus, and N.M. Emanuel',%hur.jiz. Khim., 1956,30,856.i2 F. F. Rust, J . Amer. Chem. SOC., 1957, '79, 4000.7J F. S. Dainton and T. J. Hardwick, Trans. Faraday SOC., 1957, 53, 333.7.1 T.J. Hardwick, Canad. J . Chem., 1957, 35, 437.76 C. R. Maxwell and D. C. Peterson, J . Amer. Ckem. Soc., 1957, '79, 5110.7 7 J . H. Baxendale and C. F. Wells, Trans. Faraday SOC., 1957, 53, 800.7 8 G. M. Coppinger, J . Amer. Chem. SOC., 1957, '79, 2758.79 A. W. H. Aten, K. P. Louwrier, P. Coppens, H. A. Kok, A. M. de Roos, E. Kriek,Idem, ibid., p. 428.A. Hillege, L. Vollbracht, and F. Hartog, J . Inorg. Nuclear Chem., 1956, 3, 296KINETICS OF CHEMICAL CHANGE. 49the suggestion that the pyrosulphate ion is formed as an intermediate,the mechanism being :03SO~OS032-+ + 0 3 S 0 - * S 0 3 2 - + SO,2-o,so~*so3~- __t O3f*SO*f*SO32-03~*SO*f*S032- $. *so3'- 03f*S**S032- + f*S0,2-The reduction of potassium persulphate by sodium thiosulphate was foundto be accelerated by the addition of potassium nitrate which was ascribedto the catalytic action of potassium ions.80 The rate of the reaction betweenpotassium peroxydisulphate and oxalic acid is independent of the concen-tration of the latter, however; the oxalate is capable of yielding the ionradical C,O,- and initiates chains which cause autocatalysis.81The decomposition of tert.-butyl hydroperoxide in dodecane solutionat 98.5" in a helium-swept system appears not to be a chain reaction nordoes it involve tert.-butoxy-radicals.s2 In a closed system, the rate is veryslow, probably owing to the formation of an unreactive dimer. Generationof the tert.-butoxy-radical in the presence of various types of hydrocarbonhas enabled structure to be correlated with reactivity, account being takenof the steric shielding of reactive groups from attack by the bulky butoxy-radical.83 The rate of decomposition of benzoyl peroxide in alcohols wasfound to increase as the homologous series is descended.@The oxidation of acetaldehyde by peracetic acid is believed to proceedvia an intermediate peroxide of unknown compo~ition.~~ The slow rate ofdisappearance in methanol, nitromethane, and acetone is attributed to theformation of hydrogen bonds by peracetic acid with solvent molecules.86In toluene much higher rates were encountered; in this solvent peraceticacid was found to have an infrared absorption band at 3310 cm.-l corre-sponding to an intramolecular hydrogen bond of the type MeCO*OOH.The reaction between cobaltic ion and tert.-butyl hydroperoxide or thehydroperoxide of 2-methylbut-2-ene is more rapid in dilute sulphuric acidthan in glacial acetic acid.87Oxidations by metal ions.The rate of reduction of cobaltic perchlorateby water is observed to be of the 3/2 order in ColI1 and inversely proportionalto the square of the hydrogen-ion c~ncentration.~' These kinetics areaccounted for by supposing that the cobaltic ions are present mainly asdimers. The oxidation of ethanol by ceric perchlorate in aqueous solutionsis preceded by the rapid formation of a 1 : 1 complex between the reactants,the rate-determining step being decomposition of the complex.88 A8 0 Masaji Miura, Tetsuo Miyata, Sadaichi Otani, Akira Yoltohata, and TamotsuOgawa, J .Sci. Hiroshima Univ., 1956, A , 19, 507.81 S. P. Srivastava and S. Ghosh, 2. phys. Chem. (Leipzig), 1966, 205, 332.82 B. K. Morse, J . Amev. Chew. SOC., 1957, 79, 3375.83 J . H. T. Brook, Trans. Faraday Soc., 1957, 53, 327.S4 Fujio Mashio and Shinichi Kato, M e w Fac. Ind. Arts Kj*oto Tech. Univ., Sci.8 6 R. F. Vasil'ev and N. M. Emanuel', Izvest. Akad. Nauk S.S.S.R., Otdel. khim.8 6 R. F. Vasil'ev, A. N. Terenin, and N. M. Emanuel', ibid., 1956, 403.8 7 J. A. Sharp, J., 1957, 2026.8 8 M. Ardon, ihid., p. 1811.- - - - - - - -ITechmd., 1956, 5, 51.N a u k , 1956, 38750 GENERAL AND PHYSICAL CHEMISTRY.preliminary report has appeared on the reaction between oxalate and cericions in sulphuric acid solutions.sgFormate ion autocatalyses the reduction of permanganate ions by formicacid a t low acid concentration^.^^ Further reduction after reaching theMnIV stage, i.e., MnO,, is explained by a mechanism incorporating themanganate ion.A thorough kinetic study of the oxidation of diphenyl-methanol by potassium permanganate led to the conclusion that thereaction occurs by transfer of a hydride ion H- from the diphenylmethoxideion to the permanganate Evidence has been presented to show thatboth bivalent and tervalent manganese participate in the reduction of thelatter ion by oxalate ions.92 When acraldehyde is oxidised by manganicpyrophosphate the slow step is the acid-catalysed formation of P-hydroxy-propionaldehyde from acraldehyde. 93In dilute sulphuric acid the double bonds of olefins are attacked bycobaltic ions by way of electron transfer; the carbonium ions so producedgive hydroxylic compounds which are rapidly oxidised by cobaltic ions.94These reactions do not take place in glacial acetic acid unless sulphuricacid is added and then different kinetics are obtainedag5 The results areinterpreted as being due to the formation of a stable complex cobalticsulphate-acetate ion.96It has been shown that radicals produced during polymerisation 97 andalso the free radical ad-diphenyl-p-picrylhydrazyl 49 will react with avariety of metal salts in a number of media.Hydrolysis and acid-base equilibria.Carbamic acid and a dimer ofcyanic acid have been suggested as intermediates in the hydrolysis ofcyanic acid.98 The hydrolysis of esters has been studied both for solventeffects S9 and for the effect of substitution into fluorinated esters.100 Thehydrolysis of thioacetamide is catalysed by both acids and bases withthioacetic acid appearing as an intermediate in both reactions.101 Therate of production of acetic acid from acetic anhydride and water found byobservation of magnetic resonance of hydrogen nuclei was in fair agreementwith results from direct titration.lo2 Results for the rates of solvolysisof a series of benzenesulphonates, halides, and methanesulphonates wereobtained by use of light and heavy water as solvents.The difference inrate ratios was put down to differences in the solvation of the initial states.103The acid hydrolyses of cis-[Cr en,Cl,]+ and the corresponding cobalt complex8 9 V.H. Dodson and A. H. Black, J . Amer. CWemSoc., 1057, 79, 3657.9 0 E. Abel, 2. phys. Chem. (Frankfurt), 1956, 8, 127.9 1 R. Stewart, J . Amer. Chem. SOL, 1957, 79, 3057.92 Shigeru Yamashita, Teruo Hayakawa, and Osamu Toyama, Bull. Univ. Osaka93 H. Land and W. A. Waters, J., 1957, 4313.94 C. E. H. Bawn and J. A. Sharp, ibid., p. 1854.95 Idem, ibid., p. 1866.96 J. A. Sharp, ibid., p. 2030.97 E. Collinson and F. S. Dainton, Nature, 1956, 177, 1224.98 A. R. Amell, J . Amer. Chem. Soc., 1956, 78, 6234.100 A. Moffat and H. Hunt, ibid., p. 54.101 D. Rosenthal and T. I. Taylor, ;bid., p. 2684.102 B. N. Bhar and W. Forsling, Arkiv Fys., 1957, 11, 405.103 P. M. Laughton and R. E. Robertson, Canad.J. Chenz., 1956, 34, 1714.Prefect., 1957, 5, 131.G. A. Gallagher, J. G. Miller, and A. R. Day, ibid., 1957, 79, 4324KINETICS OF CHEMICAL CHANGE. 51have similar mechanisms, indicating that they have similar electronic~onfigurations.10~The reaction H+ + OH- ---t H20 has been demonstrated to be thefastest known bimolecular reaction, having a rate constant of 1.3 x loll 1.mole-l sec.-l at 20";f05 a relaxation method was used in which electric fieldsof 105 v/cm. were applied. The application of the acidity functions h, andH , as a diagnostic for the mechanisms of acid-catalysed processes has beendiscussed.106~ 107 The slow step in the acid-catalysed hydrolysis of ethyleneoxide and its derivatives is the production of a carbonium ion which thenreacts rapidly with water to form a glycol and hydrogen ions.lo8Nuclear magnetic resonance methods have been used to study theprotolysis of methylammonium ions in aqueous solution log and acid-baseequilibria in aqueous solutions of alkylamines.l1°Higginson and Marshall have compared theoxidation of sulphurous acid in aqueous solution with that of hydrazineby the same reagents.111 The mechanisms of the reactions are similarsince the products formed depend principally upon whether the oxidisingagent favours a one- or a two-equivalent reaction.The rate of oxidationof sulphite by bromate ions indicates that the reaction proceeds throughtwo different transition states.l12 When chlorate ions bring about theoxidation then the hydroxyl radical and the hydrogen sulphite radical HSO,*are possible intermediates.l13The kinetic data for the oxidation of bromide ions in nitric acid implythat the slow step is the decomposition or rearrangement of a complex ion[N20,BrH] +.l14The aquation of halogenopentamminocobaltic ions is induced by metalions which may donate a water molecule from their hydration shells.115Sulphate ions associate with the reactants and enter the transition state.Methanol was used as solvent for the reaction of some anions with cis-[Co en2C12]+ and trans-[Co (AA),Cl,]+ (where AA is a substituted ethyl-enediamine) to suppress h y d r 0 1 y s i s .l ~ ~ ~ ~ ~ ~ Specific anion effects werefound for the effect of electrolytes on the rate of loss of chloride from[Cr(NH,),C1I2+ in aqueous solution.lls Simple and autocatalytic pathsare present for the reversible formation of complexes from Cr3+ and ~rea.11~The formation and hydrolysis of copper(I1)-pyridine complexes have beenMiscellaneous reactions.I04 J. Selbin and J.C . Bailar, J . Amev. Chew. SOC., 1957, 79, 4285.In5 M. Eigen and L. de Maeyer, Naturwiss., 1955, 42, 413.106 F. A. Long, Pvoc. Chem. Soc., 1957, 220.l n 7 F. A. Long and M. A. Paul, Chem. Rev., 1957, 57, 935.109 E. Grunwald, A. Loewenstein, and S. Meiboom, J . Chem. Phys., 1957, 27, 630.l10 Idem, ibid., p . 641.1'1 W. C. E. Higginson and J. W. Marshall, J., 1957, 447.l J 2 F. S. Williamson and E. L. King, J . Amer. Chem. Soc., 1957, 79, 5397.I L 3 E. H. Gleason, G. Mino, and W. M. Thomas, J .Phys. Chem., 1957, 61, 447.114 J. V. L. Longstaff, J., 1957, 3488.115 F. A. Posey and H. Taube, J . Amer. Chem. Soc., 1957, 79, 255.116 R. G. Pearson, P. M. Henry, and F. Basolo, J . Amer. Chem. Soc., 1957, 79, 5379.1 1 ' Idem, ibid., p . 5382.118 &I. Ikuta, H. G. McAdie, and W. MacF. Smith, Canad. J . Chem., 1956, 34, 1361.'19 K. B. Yatsimirskii and E. I. Yasinkene, Zhur. neorg. Khim., 1956, 1, 438.F. A. Long, T. G. Pritchard, and F. E. Stafford, J . Amer. Chem. Soc., 1957,79, 236252 GZNERAL AND PHYSICAL CHEMISTRY.investigated.120 Reactions of some platinum(I1) complexes with a varietyof nucleophilic reagents have been reported.121The absorption of ethylene by sulphuric acid is catalysed by copper,mercury, and silver salts.122A gradual change in the mechanism is postulated for the reactionscatalysed by gallium bromide of some alkyl bromides with benzene andtoluene in which the carbonium-ion character of the transition state increaseswith increasing branching of the alkyl g r o ~ p .1 ~ ~The stable intermediate SnCl,,C,H,Cl is involved in the exchange ofchlorine36 between stannic chloride and 2-chlorobutane in heptane.124A combination of organic reagents and radioactive isotopes has beenapplied to the study of reactions in very dilute solutions, i.e., 10-7-lo-9~;an example is the thallous-ferric r e a ~ t i 0 n . l ~ ~In September 1956 the Faraday Society held adiscussion on “ The Physical Chemistry of Processes at High Pressures ”at Glasgow University when several papers were read dealing with theeffect of pressure on chemical reactions.Laidler discussed the factorsinfluencing overall volume changes and volumes of activation for ionicreactions in water.126 The rates of dissociation of ctd-azoisobutyronitrileand pentaphenylethane have been measured in toluene at pressures up to10,000 and 1500 atm. respectively, and were found to be decreased bypressure. The effect of pressure on the dissociation equilibrium of dinitrogentetroxide in carbon tetrachloride at pressures up to 1500 atrn. was foundto be ten times as great as predicted from the changes in molecular volunie.127The acceleration by pressure of the rates of interconversion cis- and trans-1 : 2-dichloroethylene catalysed by iodine can be attributed to the increasedrate a t which iodine atoms add to the double bonds.128 Results from thedecomposition of benzoyl peroxide in carbon tetrachloride at high pressurelead to the conclusion that the effect of pressure on the rate of initiation inthe peroxide-catalysed polymerisation of styrene is ~ n i a l l .1 ~ ~A new method of kinetic analysis for reactions occurring at the air-solution interface has been developed and applied to the surface hydroxyl-ation of polyisoprenes by acidified perinanganate s0lution.1~0An attempt has been made to formulate a theory of Iiquid-phasereactions by use of the methods of non-equilibrium statistical mechanics.131It is shown that the theory gives rates no less satisfactory than thosecalculated from the transition-state theory for the reaction between bromideions and alkyl bromides.Laidler and Landskroener have developed aNo%-chemical e#ects.120 D. L. Leussing and R. C. Hansen, J . Amer. Chevn. Soc., 195?, 79, 4270.121 D. Banerjea, F. Basolo, and R. G. Pearson, ibid., p. 4055.122 M. Hellin and J. C. Jungers, Bull. Scc. chirn. France, 1957, 386.123 C . R. Smoot and €1. C . Brown, J . A Y ~ E Y . Chew SOC., 1956, 78, 6249.124 R. A. I-Iowald and J. E. Willard, ibid., p. 6217.lz5 V. I. Kuznetsov and G. V. Myasoedova, Zhur. neovg. Khim., 1956, 1, 579.126 K. J. Laidler, Discuss. Fnraday Soc., 1956, 22, 89.12’ A. EI. Ewald, ibid., p. 138.128 A. H. Ewald, S. D. Hamann, and H. E. Stutchbury, Trans. Faraday Soc., 1957,129 A. E. Nicholsoii and R. G. W.Norrish, Discuss. Faraday SOC., 1956, 22, 97.130 W. R. Dean, V. Perera, and J. Glazer, Trans. Faraday SOL, 1957, 53, 679.131 J. L. Wood and A. Suddaby, ibid., p. 1437.53, 991KINETICS OF CHEMICAL CHANGE. 53theory which relates rate constants to the dielectric constant of the solventfor reactions in which electrostatic interactions predominate.132The lack of convincing experimental evidence to support the Brgnstedtheory of the kinetic salt effect caused Barrett and Baxendale133 to studythe effect of a variety of salts on the rate constant of the reaction betweenferrous ion and CO(C,O,),~- in water. Good agreement with the theory wasobtained for ionic strengths up to 4 x 10-3~. Application of the positivesalt effect of sodium chloride on the reaction between peroxydisulphateand iodide ions has been used to calculate the ionic radius of the activationcomplex.134The methods of preparation, structure, andproperties of polyethylene,l graft copolymers,2, and block copolymers 49have been extensively reviewed, and Mandelkern has reviewed the kineticsand general features of the crystallisation of flexible polymer molecules.The theoretical treatment of stereoisomerism in high polymers has beenextended by Arcus to include alternating copolymers and the conditionsfor optical activity therein.A British Patent to the Standard Telephone and Cable Co.dis-closes one of the first successful formations of a high polymer from a 1 : 2-di-substituted ethylene (other than highly fluorinated olefins) .The monomerused was 1 : l-dichloro-2-fluorovinyl methyl ether and polymerisation waseffected by addition of boron trifluoride in liquid propane or butane, thereaction being allowed to take place at the boiling point of the solvent.The polymer is stated to be a rubber-like substance with a softening pointwell above 250".has been usedas a method for estimation of the monomer even when it is mixed withother olefins.Young's modulus of semicrystalline polymers has been consideredtheoretically 10 and comparison of calculated and experimental values fortwo widely different polyethylene samples leads to the conclusion thatcrystallite sizes in slowly cooled polyethylene vary from 250In contrast with the normal heterogeneous copper-catalysed poly-merisation of diazoalkanes, a homogeneous system has been reported 11in which the catalyst is a cuprous iodide-amine mixture.Polyethylideneas usually obtained from the polymerisation of diazoethane is a completelyamorphous substance with m. p. ca. go", but Saini, Campi, and Parodi12Polymerisation.-General.The quantitative polymerisation of 14C-labelled ethyleneto 400 A.132 K. J . Laidler and P. A. Landskroener, Tvuns. Faraday Soc., 1957, 53, 200.133 J. Barrett and J. H. Baxendale, ibid., 1956, 52, 210.134 G. M. Schwab and S. Krawczynski, 2. Plzys. Chem. (Fvankfurt), 1956, 8, 1.1 S. L. Agganval and 0. J. Sweeting, Chem. Rev., 1957, 57, 665.2 N. G. Gaylord, Intei.chem. Rev., 1956, 15, 91.3 R. Hart, I n d . chim. belge, 1956, 21, 1053, 1193.4 N.G. Gaylord, Intevchenz. Rev., 1957, 16, 3.5 R. Hart, Ind. chirn. belge, 1956, 21, 1309.6 L. Mandelkern, Chenz. Rev., 1956, 56, 903.7 C. L. Arcus, J . , 1957, 1189.8 B.P. 754,976, Standard Telephone and Cable Co.Q F. Danusso, G. Pajaro, and D. Sianesi, J . Polymer Sci., 1956, 22, 179.10 F. Bueche, ibid., p. 113.11 C . E. H. Bawn and A. Ledwith, Chem. and Ind., 1957, 1180.12 G. Saini, E. Campi, and S. Parodi, Gazzetta, 1957, 87, 34254 GENERAL AND PHYSICAL CHEMISTRY.have succeeded in preparing a crystalline polyethylidene with an m. p.above 150" by use of colloidal gold as a catalyst. It is thought that thecrystalline form of polyethylidene is produced by the influence of theheterogeneous catalyst site, i.e., colloidal gold. The preparation of thishigh-melting form of polyethylidene has been confirmed independently byBawn and Ledwith.llThe successful transformation of cis-I : 4 units in polybutadiene intocorresponding trans units has been accomplished by means of ultravioletirradiation of the polymer in the presence of a suitable sen~itizer.1~ Howeverisomerisation could not be induced in natural rubber.The molecular structure of polyethylene has been much studied 1% 15 andit has been shown l6 that when short-chain branching is corrected for, theviscosity of molten polyethylene obeys the Fox and Flory law, qM= Mi:.No simple relation between either solution viscosity or melt viscosity withnumber-average molecular weight could be found for polyethylene,l7 andNicholas 18 has amended the Harris equation relating intrinsic viscosityand molecular weight of unfractionated high-pressure polyethylenes.Astudy of the non-Newtonian behaviour of poly(viny1 acetate) solutions hasshown19 that the value of the Huggins constant k' at zero rate of shearis independent of molecular weight for a given polymer and is a fundamentalproperty associated with the inherent character of the polymer chains andtheir interactions with the solvent at a particular temperature. Otherstudies20 on the same monomer have indicated that k' is measurablysensitive to branching only for fractions possessing a certain minimumcombination of size and complexity.It was shown 21 that the absolute value of the turbidity of benzene asdetermined by Carr and Zimm is more correct than the earlier value deter-mined by Cabannes.Light-scattering measurements 22 in some branched polystyrenes ofknown structure have shown that the molecular weights and dimensionscalculated therefrom are in satisfactory agreement with the known structureof the polymers.Intrinsic viscosity-molecular weight relations have been establishedfor poly-4-vinylpyridine z3 and poly(chlorotrifluoroethy1ene) .24Fyee-radical polymerisation.Mixtures of salts of NN-dialkylaryl-amines and o-sulphobenzoic imide (saccharin) have been shown25 to beefficient initiators for the polymerisation of methyl methacrylate and13 M. A. Golub, J . Polymer Sci., 1957, 25, 373.14 L. T. Muus-and F. W. Billmeyer, jun., J . Amer. Chem. SOL, 1957, 79, 5079.15 Q.A. Trementozzi, J . Polymer Sci., 1956, 22, 187.16 W. L. Peticolas and J. M. Watkins, J . Amer. Chem. Soc., 1957, 79, 5083.17 C. E. Ashby, J . S. Reitenour, and C. F. Hammer, ibid., p. 5086.1s L. Nicolas, Makromol. Chem., 1957, 24, 173.l o S. L. Kapur and S. Gundiah, J . Polymer Sci., 1957, 26, 89.20 L. M. Hobbs, S. C . Kothari, V. C. Long, and G. C. Sutaria, ibid., 1956, 22, 123.21 P. Rempp and H. Benoit, ibid., 1957, 24, 155.22 M. H. Jones, H. W. Melville, D. W. Ovenall, F. W. Peaker, and IV. G. P. Robed-23 A. G. Boyes and U. P. Strauss, J . Polymer Sci., 1956, 22, 463.24 E. K. Walsh and H. S. Kaufman, ibid., 1957, 26, 1.26 J . Lal, R. Green, and S. Ellis, ibid., 1957, 24, 75.son, J . Colloid Sci., 1956, 11, 508KINETICS O F CHEMICAL CHANGE.55acrylonitrile. The decomposition of peroxy-carbamates has been studiedin order to determine their efficiencies as initiators of vinyl polymerisationand it was shown 26 that during the decomposition of tert.-butyl N-phenyl-peroxycarbamate (between 50" and 90") both tert.-butoxy- and phenyl-amino-radicals efficiently initiate chains.Initiation of polymerisation of styrene has been achieved by use ofelectrons supplied at a cath0de.~7 The photopolymerisation of acrylonitrilein magnesium perchlorate solution has been studied with ferric salts asinitiators.28 Dialkylsilanes have been used to initiate the polymerisationof t et rafluoroet hylene .29 Other aspects of radiochemical polymerisationare discussed in the section on Radiation Chemistry (p.68).Use of 14C-labelled benzoyl peroxide as initiator in the polymerisationof styrene shows that the fraction of initiating radicals which are benzoyloxydecreases as the monomer concentration is reduced.30The kinetics of the polymerisation of styrene and methyl methacrylateinitiated by di-terf.-butyl peroxide have been studied 31 between 60" and 98".Ethyl methyl ketone peroxide has been used32 as an initiator for thepolymerisation of several vinyl monomers and the specific rate constantsfor spontaneous and induced decomposition have been determined at 70"and 80". It was found that this initiator is comparable to benzoyl peroxideand azoisobutyronitrile in its catalytic efficiency, while its capacity fortransfer is intermediate between those of non-transferring azoisobutyronitrileand highly transferring cumene hydroperoxide.The polymerisation of acrylamide initiated by X-rays and y-rays hasbeen studied kinetically 33 along with the hydrogen peroxide-photosensitizedpolymerisation 34 at 25". Riboflavin being used as ~ensitizer,~~ the photo-polymerisation of this monomer is very fast; the rate depends upon thesquare root of the viscosity of the medium.The polymerisation of ethylene at 7000 atm.initiated by azoisobutyro-nitrile or benzoyl peroxide produces a substantially linear, high-melting(m. p. 131") polyethylene of high density.36Heat and entropy changes for the polymerisation of methacrylonitrilehave been calculated from a study of the photosensitized reaction at tem-peratures above 100".The results suggest that depolymerisation isimportant at these temperature^.^'Thomas and Webb3s suggest that the best value for the propagation2 6 E. L. O'Brien, F. M. Beringer, R. B. Mesrobian, J . -4mer. Chenz. SOC., 1957,27 J. Y. Yang, W. E. McEwen, and J. Kleinberg, ibid., p. 5833.28 Y . Grobe and E. Spode, Naturwiss., 1957, 44, 560.29 A. M. Geyer and R. N. Haszeldine, J., 1957, 1038.30 J. C. Bevington, Proc. Roy. Soc., 1957, A , 239, 420.31 J. A. Offenbach and A. V. Tobolsky, J . Amer. Chem. Soc., 1957, 79, 278.32 M. R. Gopalan and M. Santhappa, J . PoZymer Sci., 1957, 25, 333.33 E. Collinson, F. S. Dainton, and G. S. McNaughton, Trans. Faraduy Soc., 1957,34 F. S. Dainton and M. Tordoff, ibid., p.499.35 G. K. Oster, G. Oster, and G. Prati, J . Amer. Chem. SOC., 1957, 79, 595.36 R. A. Hines, W. M. D. Bryant, A. W. Larchar, and D. C. Pease, Ind. Eng. Chem.,37 S. Bywater, Canad. J . Chem., 1957, 35, 552.3s W. M. Thomas and R. L. Webb, J . Polymer Sci., 1957, 25, 124.79, 6238.53, 476, 489.1957, 49, 107156 GENERAL AND PHYSICAL CHEMISTRY.rate of the polymerisation of acrylonitrile in aqueous suspension at roomtemperature is 2 x lo4 1. mole-l sec.-l. The polymerisation of acrylo-nitrile, methacrylonitrile, and styrene in dimethylformamide has beenstudied in the presence of ferric chloride.39 In each case the participatingradicals enter into a termination reaction with the salt, with reduction toferrous chloride. Estimation of ferrous ion provides a convenient methodof determining the rate of starting of chains.Polymerisation of acrylo-nitrile in the presence of lithium salts 40 shows that the coefficients for thepropagation reaction and the transfer reactions to triethylamine and carbontetrabromide are functions of the concentration and nature of the added salt.' Monodisperse ' (polymer of nearly homogeneous molecular weight)polystyrene has been prepared by controlling the time of growth of poly-merising styrene radicals.41 This was achieved by adding excesses of freeradicals a t intervals to an emulsion system. Styrene chains initiated inone addition are then mostly terminated in the next addition. The timeof growth of the polymer chains is the interval between additions and inthis manner polystyrene samples having molecular weights between 500,000and 1,000,000 can be obtained.The polymerisation of styrene initiated by azoisobutyronitrile andbenzoyl peroxide in the presence of natural rubber 42 has been used to deter-mine the chain-transfer constants of styrene to natural rubber.Chain-transfer constants of methyl methacrylate with fourteen solvents have beendetermined at 60" and 80" with azoisobutyronitrile as initiator.43 Graftcopolymers have been obtained by polymerisation of acrylamide in thepresence of natural rubber and by the polymerisation of methyl meth-acrylate in the presence of polyi~oprene.~~Vinyl bromide, which normally produces homopolymer of only lowmolecular weight, has been successfully copolymerised with methylmethacrylate and styrene to give relatively stable compounds of highmolecular weight ,46 and ally1 alcohol, another monomer which yields onlylow homopolymer, has been copolymerised with acrylonitrile to produce apolymer of relatively high molecular weight .47 The reactivity ratios weredetermined for the latter reaction.From a study of the copolymerisationof vinylidene cyanide with a series of olefinic monomers Ham 48 concludesthat acrylonitrile is anomalous in that it gives rise to repulsive effects, whilstother monomers containing methylenic double bonds behave normally.Two new monomers, I : 2-dimethylenecyclohexane 49 and vinyl tri-fluoroacetate, 50 have been polymerised to products of high molecular weightwith typical free-radical initiators.39 C.H. Bamford, A. D. Jenkins, and R. Johnston, Proc. Roy. Soc., 1957, A , 239, 214.4 O Idem, ibid., 1957, A , 241, 364.4 1 J. P. Bianchi, F. P. Price, and B. H. Zimm, J . Polymer Sci., 1957, 25, 27.42 Y . Minoura, Y. Mori, and M. Imoto, Makromol. Chew., 1957, 24, 205.43 R. N. Chadha, J. S. Shukla, and G. S. Misra, Trans. Faraday Soc., 1957, 53, 240.44 G. Oster and 0. Shibata, J . Polymer Sci., 1957, 26, 233.4 5 P. W. Allen and F. M. Merrett, ibid., 1956, 22, 193.4G G. Blamer and L. Goldstein, ibid., 1957, 25, 19.4 7 G. Oster and Y. Mizutani, ibid.. 1956, 22, 173.48 G. E. Ham, ibid., 1957, 24, 349.4 9 A. T. Blomquist and D. T. Longone, J . Amer. Chem. Soc., 1957, 79, 3916.5 O H. C. Haas, E. S. Emerson, and N.W. Schuler, J . Polymer Sci., 1956, 22, 291KINETICS OF CHEMICAL CHANGE. 57The use of ionizing radiationsto initiate, degrade, and graft polymer chains has been briefly reviewed 51and Grassie 52 has reviewed the r61e of abnormal linkages in polymerdegradation. The result of irradiation of polymers has been shown to beconsiderably affected by temperature 53 and the presence of oxygen.=Irradiated polymers, presumably containing active free-radical sites, havebeen used to initiate the polymerisation of 1%-labelled acrylonitrile 55 andthus to determine the degree of grafting.By a study of the degradation of polystyrene and cellulose, Bryce andGreenwood56 have shown that changes in intrinsic viscosity [q] are notthemselves a true measure of the degradation rate and that the often-quoted apparent limit in [q] or (qSp/c) is fallacious.A series of elementary processes for cross-linking and scission reactionsduring the irradiation of polymers have been suggested and consideredtheoretically on the basis of free-radical intermediates.57 Two differentmechanisms have been suggested for the mechanism of the radiation cross-linking of polyethylene : one involves vinylene groups as cross-linkingintermediates 5 8 3 5 9 and the other 6o is based upon intermediates of cationtype.Pyrolysis of polymers and copolymers of styrene and di- and tri-vinyl-benzene indicates that the thermal stability of the polymers increases withthe degree of cross-linking,61 and it has also been shown 62 that the rapidinitial fall in molecular weight of polystyrene samples during thermaldepolyrnerisation is due to disproportionations at weak Links.The cross-linking and degradation of seven polyacrylates have been studied underthe influence of 1000 kvp electrons 63 and it is believed that the presenceof a hydrogen atom alpha to the alcoholic oxygen of the ester group contri-butes strongly to the cross-linking reactions, although it was shownconclusively that no cross-linking occurred during the degradation ofpoly(methy1 me thacrylate) under the same influence.@The number of scissions in poly(methy1 methacrylate) for a given doseof y-irradiation is decreased by the presence of air, small amounts of benzene,and by lowering the temperature to -196". Furthermore it was suggestedthat when Folystyrene is similarly treated the phenyl rings are involved in~ross-linking.~~ Further studies have been made of the ceiling temperatureof polymerisation, and Cook and Ivin have studied the equilibrium betweenPolymer degradation and depolymerisation.51 F.S. Dainton, J . Oil Colour Chemists' Assoc., 1957, 40, 830.52 N. Grassie, Cheun. and Iizd., 1957, 537.53 A. Charlesby and W. H. T. Davisson, ibid., p. 232.64 P. Alexander and D. Toms, J . Polymer Sci., 1956, 22, 343.6 5 J. C. Bevington and D. E. Eaves, Nature, 1956, 1'9.8, 1112.5ti W. A. J. Bryce and C . T. Greenwood, J . Polymer Sci., 1957, 25, 480.57 R. Simha and L. A. Wall, J . Phys. Chetn., 1957, 61, 425.58 R. W. Pearson, J . Polymer Sci., 1957, 25, 189.F 9 M.Dole, D. C. Milner, and T. F. Williams, J . Amer. Clzem. Soc., 1957, YO, 4809.6 o 13. G. Collyns, J. F. Fowler, and J. Weiss, Chem. and I n d . , 1957, 74.61 F. H. Winslow and W. Matreyek, J . Polymer Sci., 1956, 22, 315.N. Grassie and W. W. Ken, Trans. Faraday SOL, 1957, 53, 234.O3 A. R. Shultz and F. A. Bovey, J. Polymer Sci., 1956, 22, 485.64 A. R. Shultz, P. I. Roth, and G. B. Rathmann, ibid., p. 495.6 5 L. A. Wall and D. W. Brown, J. Phys. Chem., 1957, 61, 12958 GENERAL AND PHYSICAL CHEMISTRY.ethyl methacrylate and its polymer; 66 McCormick 67 has found the ceilingtemperature of ct-methylstyrene to be 61” and has shown that the valuedepends only upon the monomer concentration.Condensation polymerisation. The apparently different interpretations 68of the kinetic behaviour of the polymerisation of N-carboxyanhydridesinitiated by amines have been shown 69 to be due to slight variations in thepurity of the monomeric N-carboxyanhydride. Other work 70 on thepolymerisation of N-carboxyanhydrides initiated by amines shows thatthe two successive rate constants, k,, slower, and k2b faster, can be correlatedwith the formation of low- and high-molecular weight polypeptides, res-pectively, and that the polymerisation proceeds at two successive ratesfollowing a very rapid initiation.71 It was also shown 72 that the aminegroups are mostly preserved throughout the polymerisation but are losteasily, during polymer isolation, by cyclisation of the end-groups.A rapid titration method has been developed 73 for the estimation ofprimary mine and carboxyl end-groups in polyhexanolactam which givesresults in satisfactory agreement with those calculated from measurementsof solution viscosity. The influence of water on the degree of polymerisationof polyhexanolactam is reduced by increasing the concentration of“ stabiliser.” 74 The molecular-weight distribution in the last stage of thehydrolytic polymerisation of 6-hexanolactam is characterised by theequilibrium in the polymerisation, depolymerisation, and transamidationreaction^,^^ and this result is identical with the distribution designated byFlory 76 as most probable.From a study of the intrinsic viscosity of the polyesters of 9 : 10-di-hydroxyhexadecane-1 : 16-dicarboxylic acid it was concluded 77 thatbranching or the formation of a three-dimensional network had occurred.The rate of isomerisation of but-2-ene by theboron trifluoride-water complex in ethylene &chloride is given by theexpression : As the concentration ofwater is increased the rate rises to a maximum and then decreases.7s Theionisation of triphenylmethyl chloride in various solvents has been investi-gated ~pectrophotometrically.~~ The cationic polymerisation of styrenein the presence of poly-9-methoxystyrene produces a graft copolymer.8oThe equilibrium polymerisation of an olefinic monomer in the presenceG 6 R. E. Cook and K. J. Ivin, Tram. Faraday Soc., 1957, 53, 1132.67 H. W. McCormick, J . Polymer Sci., 1957, 25, 488.68 D. 6. H.Ballard and C. H. Bamford, J . Amer. Chem. Soc., 1957, 79, 2336.60 P. Doty and R. D. Lundberg, ibid., p. 2338.70 M. Idelson and E. R. Blout, ibid., p. 3948.71 R. D. Lundberg and P. Doty. ibid., p. 3961.72 J. C. Mitchell, A. E. Woodward, and P. Doty, ibid., p. 3955.73 V. A. Mvagkov and A. B. Pakshver, Zhur. Qriklad. Khim., 1956,29, 1703; Chem.Cationic polymerisation.Rate = R[BF,] [BF,,H,O] [Butene].Abs., 1957, 51: 4315.74 T. G. Majury, J . Polymer Sci., 1957, 24, 488.7 5 2. MenEik. Chem. Listv. 1957, 51. 823; Chem. Abs., 1957, 51. 12536.7 6 P. J . Flory, “ Principles of -Polymer Chemistry,” Cornell Univ. Press, Ithaca,7 7 P. R. Bhattacharya, J . Sci. I n d . Res., India, 1956, 15, B, 721.7 8 J. M. Clayton and A. M . Eastham, J . Amer. Chem. Soc., 1957, 79, 5368.7 u A.G. Evans, I. H. McEwan, and J. H. Thomas, J., 1957, 4644.8 0 H . C. Haas, P. M. Kamath, and N. W. Schuler, J . Polymer Sci., 1957, 24, 85.New York, 1953, p. 321KINETICS OF CHEMICAL CHANGE. 59of an ionic initiator has been considered theoretically 81 and it is shown thatthe equilibrium degree of polymerisation p , is not solely a function of thefractional conversion, as in condensation polymerisation.A kinetic investigation of the polymerisation of alkyl vinyl ethers,catalysed by the boron trifluoride-ether complex,82 has shown that anincrease in the dielectric constant increases the rate of polymerisation butdecreases molecular weight ; addition of water lowers the molecular weightwithout affecting the rate of polymerisation. It is suggested that initiationis caused by an ethyl cation from the catalytic species Etf*BF3*OEt-.Thecationic polymerisation of the vinyl ethers has been briefly re~iewed.8~Study of the polymerisation of ethylene oxide catalysed by stannic chlorideshows that two polymer molecules are produced for each molecule of catalystand that chain termination occurs with catalyst destruction and no chain-transfer. The polymerisation catalysed by boron trifluoride, however,yields much dimer owing to the extensive occurrence of chain-transferwithout consumption of catalyst.84 The introduction of 9-methoxy-groups into styrene increases the reactivity of the double bond by a factorof 400. Consequently, chain-transfer and branching are reduced andpoly-P-methoxystyrene is more linear than polystyrene.85 The kineticsof the polymerisation of a-methylstyrene catalysed by boron trifluoride-ether-water complex and the kinetics and mechanism of the polymeris-ation of styrene catalysed by the chloroacetic acids 87 have been studied.Polymerisation of isobutene in ethyl chloride catalysed by aluminiumtrichloride shows a clear-cut dependence of molecular weight on catalystconcentration. The molecular weight passes through a maximum as thecatalyst concentration is increased and the position and height of thismaximum are very sensitive to traces of hydroxylic impurity.88 Thepolymerisation of benzyl perchlorate and some substituted benzyl per-chlorates is thought to proceed by a carbonium-ion mechanism.89High-energy radiation has been used to polymerise isobutene at lowtemperatures and it was therefore concluded that carbonium ions areproduced by irradiation and initiate the polymerisation.The evidencefor this conclusion is not decisive, however, since the polymerisation isinhibited by oxygen and by quin01.~~Afzionic and stereospeciJic polymerisation. The polymerisation ofa-methylstyrene initiated by metallic sodium, in the absence of oxygen,has been described 91 and the properties of the polymer compared with thoseof polystyrene. The suggested mechanism for the anionic polymerisationof vinyl monomers initiated by electi-on-transfer from the sodium-naphthaleneA. V. Tobolsky, J . Polymer Scz., 1957, 25, 220.88 J . D. Coombes and D.D. Eley, J., 1957, 3700.83 D. D. Eley, J . Oil Colour Chemists’ Assoc., 1957, 40, 810.a4 D. J. Worsfold and A. M. Eastham, J . Amer. Chem. Soc., 1957, 79, 897, 900.n5 I-’. M. Kamath and H. C. Haas, J . Polymer Sci., 1957, 24, 143.D. J . Worsfold and S. Bywater, J . Amer. Chem. Soc., 1957, $9, 4917.B 7 C. P. Brown and A. R. Mathieson, J., 1957, 3608-3639.8 8 2. Zliimal, L. Ambroi, and K. Veseljr, J . Polymer Sci., 1957, 24, 286.B9 P. F. G. Praill, J . , 1957, 3162.W. H. T. Davison, S. H. Pinner, and R. Worrall, Chem. and Ind., 1957, 1274.91 G. D. Jones, R. E. Friedrich, T. E. Werkema, and R. L. Zimmerman, Ind. Eng.Cheni., 1956, 48, 212360 GENERAL AND PHYSICAL CHEMISTRY.complex leads to the prediction that the degree of polymerisation isgiven by the ratio [monomer] : [t x catalyst].This prediction has beenverified experimentally for polybutadiene, polyi~oprene,~~ and poly-styrene.93 In the case of the last polymer it was also possible to show thatthe number-average and weight-average molecular weights were approxi-mately equal, also as required by the mechanism suggested by S ~ w a r c . ~ ~The polymerisation of vinyl monomers by boron trialkyls is thought to beanionic in character. A solution of triethylboron in hexane is an effectiveinitiator for the polymerisation of acrylonitrile, methyl methacrylate, vinylchloride, and vinyl acetate 95 and tributylboron has been used to initiatethe polymerisation of styrene, acrylonitrile, and methyl methacrylate. 96It was also found that the tributylboron-catalysed polymerisation ofacrylonitrile was considerably activated by the addition of 2 moles yo ofboron trifluoride-ether complex.97The polymerisation of isoprene initiated by organo-alkali compoundshas been much studied and it appears that the structure of the polymerdepends upon the solvents 9 8 9 9 9 and the alkali metal loo used. When thepolymerisation initiated by lithium metal or lithium alkyls is carried outin benzene or heptane, a precipitate forms and the polymerisation appearsto take place as a surface reaction. This type of heterogeneous poly-merisation produces a polyisoprene with more than 90% of cis-1 : 4structure.98 If the polymerisation initiated by lithium or lithium alkylsis carried out in ether 98 or tetrahydr~furan,~g an apparently homogeneoussystem results and the polyisoprene is a mixture of 3 : 4 and 1 : 2 units.The use of phenylsodium or benzylsodium as initiator loo produces inheptane (i.e., a heterogeneous system) a polyisoprene containing 83% of3 : 4-units, while in tetrahydrofuran solution (i.e., a homogeneous system)the polymer contains 79% of trans-1 : 4 units.The stereospecific polymerisation of olefins is extensively studied inmany countries, but so far most of the published information comes fromNatta’s laboratory in Milan. He has reviewed the progress in this fieldin several publications.101-104 Other reviews of Ziegler-type polymerisationhave been p u b l i ~ h e d , ~ ~ ~ , ~ ~ ~ and Eirich and Mark lo7 have consideredtheoretically the heterogeneous polymerisation of olefins.Details of a92 H. Brody, M. Ladacki, R. Milkovitch, and M. Szwarc, J . Polymer Sci., 1957,25, 221.93 R. Waack, A. Rembaum, J. D. Coombes, and M. Szwarc, J . Amer. Chem. Soc.,1957, 79. 2026.B4 M. Szwarc, Nature, 1956, 178, 1168.g5 J. Furukawa, T. Tsuruta, S. Inoue, J . PoZymer Sci., 1957, 26, 234.9 6 G. S. KoIesnikov and N. V. Klimentova, Izvest. Akad. Nauk S.S.S.R., Otdel.9 7 G. S. Kolesnikov and L. S. Fedora, ibid., p. 236; Chem. Abs., 1957, 51, 11291.9 5 H. Hsieh and A. V. Tobolsky, J . Polymer Sci., 1957, %, 245.99 H. Hsieh, D. J. Kelley, A. V. Tobolsky, ibid., 1957, 26, 240.100 H. Morita and A. V. Tobolsky, J . Amer. Chem. Soc., 1957, 79, 5853.G. Natta, Mod. Plastics, 1956, 34, 169.102 Idem, Chimica e Industria, 1956, 38, 751.103 Idem, Chimie et Industrie, 1957, 77, 1009.104 Idem, Chem.and Ind., 1957, 1520.105 E. G. Curphey, Brit. Plastics., 1957, 486.108 F. Eirich and H. Mark, J . Colloid Sci., 1956, 11, 748.107 Idem, Kunststoffe-Plastics, 1956, Hft. 2.khim. Nauk, 1957, 652; Chem. Abs., 1957, 51, 15458KINETICS OF CHEMICAL CHANGE. 61laboratory study of the Phillips low-pressure process for the polymerisationof olefins have been published together with a review of the normal-pressurepolymerisation of ethylene by aluminium alkyls.losThe stereospecific polymerisation of propene to isotactic polymers, withthe system AlEt,-TiCl, as catalyst, has been studied in detail.log~l10 Therate of polymerisation depended on the partial pressure of propene, theconcentration of titanium trichloride, and the temperature.It was con-cluded that the polymerisation was truly heterogeneous, and with stabilisedcatalysts the rate of polymerisation was constant for a given partial pressureof propene. The activation energy for the polymerisation is 12-14 kcal.mole-] and the effect of variables on the molecular weight and stereoisomericcomposition has been determined. Similar studies were made on thesystem propene-trie thylaluminium-tit anium tetrachloride l11 and it wasfound that the catalyst loses 75% of its activity within 40 minutes ofits preparation. The best rates of polymerisation were obtained with themolar ratio AlEt, : TiC1, = 2 : 1 but greatest stereospecificity was obtainedwith the molar ratio 3 : 1.The requirements for the formation of isotacticpolymer in such systems and the effect of using titanium compounds, otherthan TiCl,, have been discussed.l12~ 113Polymerisation of isobutene in the presence of triethylaluminium andtitanium tetrachloride was most efficient at low temperatures and thepolymer produced did not correspond to conventional polyisobutene sinceit contained one methyl side-chain on every third carbon atom.ll4Polybutadiene has been prepared by use of a catalyst made from triethyl-aluminium and chromium acetylacetone derivative.l15 When the molarratio A1 : Cr was less than 6, syndiotactic * poly-1 : 2-butadiene was obtained.If the ratio was greater than 6 however, isotactic poly-1 : 2-butadiene wasthe principal product.Isoprene can be polymerised by using a catalyst made from triethyl-aluminium and titanium tetrachloride to give a polyisoprene resemblingnatural rubber in that it contains more than 90% of cis-1 : 4 enchainment.Optimum conditions for this polymerisation are a molar ratio A1 : Ti = 1,and when this ratio exceeded 2 no polymer was obtained.ll6Nat ta has concluded 115 that the active Ziegler-type polymerisation108 R.Mihail, S. Bittmann, F. Stoenescu, and P. Corlateanu, Rev. Chim. Min. Ind.l o * G. Natta, I. Pasquon, and E. Giachetti, Angew. Chem., 1957, 69, 213.110 Idem, Makromol. Chem., 1957, 24, 258.111 G. Natta, P. Pino, G. Mazzanti, and P. Longi, Gazzetta, 1957, 87, 549.112 G. Natta, P. Pino, and G.Mazzanti, ibid., p. 528.113 G. Natta, P. Pino, G. Mazzanti, and P. Longi, ibid., p. 570.11* A. V. Topchiev, B. A. Krentsel, N. F. Bogomolova, and Yu. Ya. Gol’dfarb,Uoklady Akad. Nauk, S.S.S.R., 1956, 111, 121.115 G. Natta, Paper presented a t the International Meeting on Chemistry of Co-ordination Compounds, Rome, Sept. 1957.116 Chenz. Eng. News, 1957, 38, 81.Chim. (Roumania), 1957, 8, 399.To be published in Ricerca scienti$ca.* The words “ isotactic ” and “ syndiotactic ” were suggested by Natta to describepolymer molecules in whose backbone chain the asymmetric carbon atoms are in regu-lar steric arrangement. In isotactic molecules the steric configuration is constant (all‘‘ D ” or ‘‘ L”), and in syndiotactic molecules it alternates between each asymmetric atomand its neighbour.Polymer molecules having a completely random arrangement ofsteric configurations are called “ atactic ”62 GENERAL AND PHYSICAL CHEMISTRY.catalyst is a complex containing organometallic bonds and more than onemetal atom. The most active catalysts are those formed by the reactionbetween an alkyl of a highly electropositive metal having a small diameter,e.g., beryllium, aluminium, or lithium, and a crystalline halide of a transitionmetal of Groups IV-VI in which the metal is in a valency state less thanthe maximum, e.g., TiCl,, TiCl,, VCl,, etc. In support of this theory, soluble,crystalline complexes have been isolated from the reaction between dicyclo-pentadienyltitanium dichloride and triethylaluminium or other alkyl-alumin-ium chl~rides.ll~~-~ These compounds are of the type [C,H,] 2TiC1,A1R2Cland slowly polymerise ethylene at low temperature and pressure.When R is phenyl, i.e., when the complex is prepared from triphenyl-aluminium, phenyl end-groups can be detected in the infrared spectrumof the polyethylenes prepared. The reaction of dicyclopentadienyldiphenyl-titanium with triethylaluminium, however, gave a complex which poly-merised ethylene to a product not containing phenyl end-groups.Fromthese and similar observations, Natta concluded 115 that chains grew byinsertion of monomeric units between the aluminium-alkyl anion bonds inthe catalytic complex. It is suggested also that the insertion of mono-meric units probably proceeds through a six-membered cyclic intermediateand a similar mechanism has been suggested independently by Julia.118X-Ray investigation 115 of the compound [C5H,],TiCl2,AlEt, hasestablished the presence of chlorine bridges between aluminium and titaniumwith a Ti-Cl distance of about 2-5 and a Ti-C1-Al angle of approximately90".on these soluble crystalline titanium-aluminium complexesconfirmed that the titanium was present in the tervalent state and that theprepared complex was a poor catalyst for polymerisation of ethylene.Introduction of small amounts of oxygen into the ethylene, before it waspolymerised, made the soluble complex as efficient a catalyst as the con-ventional Ziegler catalysts made from titanium tetrachloride.It wastherefore inferred that the presence of oxygen in the monomer oxidisedsome of the tervalent titanium present in the catalyst complex, and thathigh catalytic activity in this system depended upon the presence of somequadrivalent titanium compound.It has also been suggested120 that the effective Ziegler catalyst is atitanium alkyl which may even give rise to a free-radical type of poly-merisation.121 These suggestions are supported by the isolation 122 of puretitanium alkyls of the type RTiC1, and R,R2TiC12.The alkyltitaniumchlorides are much more stable than had hitherto been predicted and canOther work117 ( a ) G. Natta, P. Pino, G. Mazzanti, U. Giannini, E. Mantica, and M. Peraldo,J . Polymer Sci., 1957, 26, 120; (b) idem, Chimica e Industria, 1957, 39, 19; ( c ) G.Natta,U. Giannini, G. Mazzanti, and P. Pino, Angew. Chem., 1957, 69, 686; (d) idem, J.Amer. Chern. SOC., 1957, 79, 2975.11s M. Julia, Compt. rend., 1957, 245, 70.119 D. S. Breslow and N. R. Newburg, J . Anaer. Chem. SOC., 1957, 79, 5072.lZo (a) C. 0. Ncnitescu, C. Huch, A. Huch, N. Dumitrescu, and M. Gavat, Rev.Chim. hlin. I n d . China. (Roumania), 1957, 8, 395; Chem. Abs., 1957, 51, 17230; (b)C. D. Nenitescu, C. Huch, and A. Huch, Angew. Chem., 1956, 68, 438.121 H. N. Friedlander and K. Oita, I n d . Eng. Cheun., 1957, 49, 1885.122 Belgian Pat. No. 553477, Farbwerke HoechstKINETICS OF CHEMICAL CHANGE. 63be used to catalyse the polymerisation of ethylene at room temperatureand pre~sure.1~3 Polymerisation does not begin however until some of thealkyltitanium chloride has decomposed (presumably to form TiCl, and analkyl radical) or until small quantities of TiCl, are added to the reactionmixture.The polymerisations were carried out in aliphatic hydrocarbonsand it seems likely that the effective catalyst is a complex between thealkyltitanium chloride and crystalline titanium trichloride. Studies on theAlfin catalyst system,l% which also produces crystalline poly-a-olefins,confirm Natta’s conclusion that a solid phase is necessary for the formationof is0 t actic polystyrene.Investigation of the properties of isotactic polymers 125, 126 and linearpolyethylenes 1279 128 in solution by light scattering, osmotic pressure, andviscometric techniques shows clearly that, in solution, there is no significantdifference between atactic and isotactic polymers.Thus the intrinsicviscosity-molecular weight relations for atactic and isotactic polymers areessentially the same, although in the case of polystyrene the second virialcoefficient was found to vary for the two types of p 0 1 y m e r . l ~ ~ ~ ~ ~ ~ Similarconclusions have been drawn from a study of the changes of density withoutchange of phase which occur in solutions of some poly-(n-a-olefin~).~~1The preparations and properties of some propene polymers containingblock units of isotactic and atactic structures, Le., “ stereoblock ” copolymers,have been described 132 and the copolymerisation of ethylene with othera-olefins, with use of Ziegler-type catalysts, has been inve~tigated.1~3~ 134Radiation Chemistry.-Two annual reviews have been publishedcovering most aspects of this subject, and specialised reviews on the effectsof irradiation on solids,3 ionising radiation and polymer chemistry,4 thepreparation of organic compounds by radiation chemistry and the poly-merisation of unsaturated compounds by y-rays.The yield for the X- and y-ray induced oxidation of ferrousions in acid aqueous solution (Fricke dosimeter) has been determined 7 forradiations of various energies. The G values [number of ferric ions producedper 100 ev absorbed] were: 60 kvp X-rays, 13.1; 100 kvp X-rays, 14.7;l23 Belgian Pat.No. 553475, Farbwerke Hoechst.124 S. L. R. Williams, J . Van Den Berghe, K. R. Dunham, and W.J . Dulmage,lZ5 F. Ang, J . Polymer Sci., 1957, 25, 126.126 G. Natta, F. Danusso, and G. Moraglio, Makromol. Chem., 1956, 20, 37.lZ7 H. S. Kaufman and E. K. Walsh, J . Polymer Sci., 1957, 26, 124.lZ8 L. H. Tung, ibid., 1957, 24, 333.F. Danusso and G. Moraglio, ibid., p. 161.130 F. Ang and H. Mark, Monatsh., 1957, 88, 427.131 G. Natta, F. Danusso, and G. Moraglio, J . Polymer Sci., 1957, 25, 119.132 G. Natta, G. Mazzanti, G. Crespi, and G. Moraglio, Chimica e Industria, 1957,133 G. Natta, G. Mazzanti, A. Valvassori, and G. Pajaro, ibid., p. 733.134 G. Mazzanti, A. Valvassori, and G. Pajaro, ibid., pp. 743, 825.Dosimetry.J . Amer. Chem. Soc., 1957, 79, 1716.39, 275.W. M. Garrison, Ann. Rev. Phys. Chem., 1957, 8, 129.Ann. Reports, 1956, 53, 35.M.Daniels and J. Weiss, Research, 1957, 10, 341, 396.F. S. Dainton, J . Oil Colour Chemists’ Assoc., 1957, 40, 830.G. 0. Schenk, Angew. Chem., 1957, 69, 579.M. LszAr, R. Rado, and N. Kliman, Chem. Zvesti, 1957, 11, 230.J . L. Haybittle, R. D. Saunders, and A. J . Swallow, J . Chew. Phys., 1056,25, 131 364 GENERAL AND PHYSICAL CREMISTRY.220 kvp X-rays, 15.0; 30 Mev X-rays, 16.3; 6oCo y-rays, 15.5. The Gvalues for this system have also been determined as 14.9 0.8 for 250 kvpX-rays and 14.0 0.8 for 50 kvp X-rays, rather less than the value15.6 & 0.4 for 6oCo y-rays. The G values were found to be 15.6 and 15.7for electrons of energies 6.3 and 16 Mev respectively. The G value for theoxidation of air-saturated 3 x 10-3~~-ferrous ammonium sulphate in 0 .8 ~ -sulphuric acid by 4 Mev electrons has bzen determined 10 as 14.3.The radiation-induced oxidation of ferrous ion in air-saturated 0.4~-hydrochloric acid differs l1 from that in sulphuric acid in that the productionof ferric ions is not linear with dose. The initial G value, 15.8, falls withincreasing dose. The G values12 for oxidation of 0.0OlM-ferrous ion areapproximately 10.3 and 8-0 for high-energy deuterons and helium ionsrespectively. The values l3 were 4.22 and 5.69 for ionising radiation fromthe (n,a) reactions on boron and lithium respectively, in aerated solution,and the estimated value for the 2.7 Mev triton recoil was 6.7.The sensitivity of the ferrous sulphate dosimeter has been increased 14by estimating ferric iron with thiocyanate, and it has been shown that theG value is constant for X-rays in the range 0-5-2.3 A.The addition ofbenzene or cyclohexane to the ferrous sulphate dosimeter system leads 15 toa non-linear calibration. A neutron-insensitive y-ray dosimeter depends 16on the production of acid in stabilised chloroform or tetrachloroethylene.Solutions of dithizone in organic solvents show1' colour changes onirradiation with y-rays for doses as low as 100 rads, but various complicationsrender them unsuitable for dosimetry.Diffusion-controlled chemical reactions in particletracks have been studied,l8 and the theory was applied to the radiolysis ofwater. The quantity of hydrogen peroxide produced in acid solutiondepends l9 in a complicated manner on the pH, a result interpreted in termsof reactions involving the dissociation of hydrogen peroxide and HO,.and *OH.The yields of hydrogen peroxide obtained by irradiating air-free aqueoussolutions of acrylamide with X-rays have been found20 to depend on theinitial concentration of acrylamide. The results are consistent with theview that acrylamide can react with the hydrogen atoms and hydroxylradicals which would otherwise induce the reaction between the '' molecular "hydrogen and hydrogen peroxide produced. The radiolysis of aeratedsulphuric acid solutions with y-rays leads 21 to the formation of peroxymono-and peroxydi-sulphuric acid. The latter is thought to arise from theAqueous solutions.* M. H. Back and N. Miller, Nature, 1957, 179, 321.9 J.Zsula, A. Luizzi, and J. S. Laughlin, Radiation Res., 1957, 6, 661.1 0 J. P. Keene, ibid., p. 424.11 H. A. Schwarz, J . Amer. Chevrz. Sac., 1957, 79, 534.12 R. H. Schuler and A. 0. Allen, ibid., p. 1666.1:) R. H. Schuler and N. F. Barr, zbid., 1956, 78, 5756.14 S. Rosinger, 2. phys. Chem. (Frankfurt), 1957, 10, 310.1 5 C . Vermeil, Anm. Chim. (France), 1956, 13, 641.16 S. C. Sigoloff, Nucleonics, 1956, 14, Oct., 54.17 J . Wilkinson and H. J . M. Fitches, Nalztve, 1957, 179, 863.1s L. Monchik, J. L. Magee, and A. H. Samuel, J . Chem. Phys., 1957, 26, 935.19 A-M. Koulkes-Pujo, Compt. rend., 1956, 243, 1865.20 B. Collinson, F. S. Dainton, and G. S. McNaughton, Trans. Faraday Soc., 1937,21 M. Daniels, J. Lyon, and J. Weiss, J., 1957, 4388.53, 357KINETICS OF CHEMICAL CHANGE.65intermediate formation of hydrogen sulphate radicals with subsequentdimerisation. The G values 22 for evolution of hydrogen from aqueous calciumnitrate solutions in a flux of fast neutrons and y-rays decrease greatly withincreasing concentration, an effect attributed to the reaction NO,- + H _tNO, + OH-. The y-irradiation 23 of alkaline solutions of potassiumchloride leads to the liberation of free chlorine in solutions saturated withair or oxygen, the yield of chlorine being directly proportional to the energyabsorption over the range 2 x 1017-1 x 10l8 ev/ml.In the decomposition of sodium azide in solution in liquid ammonia oraqueous mercuric chloride, by irradiation with X-rays, the azide ionsdecompose 24 mainly to nitrogen molecules and electrons.Johnson and Weiss25 found that the reduction of ceric salts in diluteaqueous solutions showed initial values of G(CeIII) = 3.15 0.10 and2-45 0.08 for 200 kv X-rays and 6oCo y-rays respectively, both in thepresence and absence of oxygen.The second of the above values wasconfirmed by Whittaker 2G who obtained 2-36 &- 0.12. The radiolysis ofcerous ion-ceric ion-formic acid-sulphuric acid mixtures gave results 27interpreted by the assumption that cerous ion, formic acid, and sulphuricacid compete for reaction with hydroxyl radicals. The kinetics of the self-reduction (as a consequence of a-particle emission) of ainericium(v) andamericium(v1) in perchloric acid solution have been studied.28 Americium(v)gave only americium(m), the kinetics indicating that the reaction can beattributed to reducing species produced by a-particle bombardment of thewater.Americium(v1) gave americium(v) and finally americium(II1).Plutonium(v1) in sulphuric acid solution irradiated with y-rays is reduced 29only as far as plutonium(1v). ?-Irradiation causes oxidation 30 of aeratedferrocyanide to ferricyanide in solutions of pH less than 11, with G valuesThe irradiation with X-rays of aqueous solutions of methylene-blue withan excess of a second organic solute has been studied.31 The methylene-bluecan be reduced by hydrogem atoms and also by radicals produced from theadded organic compounds. In the presence of glucose, in a nitrogenatmosphere, reduction occurs on y-irradiation 32 (G = 5.2) but oxida-tion sensitised by ferric ion occurs with G == 7.8 equiv.for the yieldof oxidised dye and 8.2 equiv. for the yield of ferrous ion. In a stronglyacid solution containing ethanol a semiquinone free radical is produced.33The irradiation 34 with X-rays of aqueous methylene-blue solutions contain-ing ethanol, benzoate, or lactate showed, in oxygen-free solution, a reversibleup to 7.5.22 R. G. Sowden, J . Amer. Chem. SOC., 1957, 79, 1263.23 A. M. Kabakchi, Zhur. jiz. Khiin., 1956, 30, 1906.24 H. G. Heal, Tvans. Faraday SOC., 1957, 53, 210.25 G. R. A. Johnson and J. Weiss, PYOC. Roy. SOC., 1957, A , 240, 189.4 6 B. Whittaker, Nature, 1957, 180, 1302.2 7 T. J. Sworski, Radiation Res., 1957, 6, 645.28 G.R. Hall and T. R. Markin, J . Inorg. Nucleav Chein., 1957, 4, 296.29 M. Pa&, C. Ferradini, and M. Haissinsky, Gompt. rend., 1967, 245, 1138.30 X. Tarrago, E. Masri, and M. Lefort, ibid., 1957, 244, 343.31 E. Hayow, G. Scholes, and J. Weiss, J., 1957, 301.32 A. I. Chernova, V. D. Orekhov, and &I. A. Proskurnin, Zhzir.jz. Khinz., 1956,30,1343.33 A. J. Swallow, J., 1957, 1553.34 M. J. Day and G. Stein, Radiation Res., 1957, 6, 666.REP.-VOL. LTV c66 C E N E RAT, AN 1) 2'1171 SIC A J, CHlShl I STRY.reduction attributed to the reducing action of free radicals produced fromthe added solutes.Gases. The tritium p-ray-induced exchange between deuterium gas andwater vapour containing tritiated water has been investigated 35 to measurethe yields of radical-pairs (G = 11.7) and amount of water decomposed inirradiated water vapour.Exchange takes place by a chain mechanismabove 150". Exchange of deuterium between deuterium oxide and dissolvedhydrogen, under irradiation with y-rays, has been studied 36 by mass spectro-metry. The reaction rate conforms to the exponential exchange law.Work on the decomposition of carbon dioxide by ionising radiation hascontinued37 with the use of the gas under pressures of 1-50 atm. and theliquid, and irradiation from a pile or fission fragments. The basic mechanismpreviously described3* was confirmed. G values for the decomposition ofcarbon dioxide ranged from 0-005 to 8-5. The decomposition of ammoniainduced by a-particles has been studied39 as a function of pressure andintensity, and the extent of gas-phase and wall reactions estimated.Thedecomposition of nitric oxide by fission fragments40 shows an overall Gvalue of 9.5 at lo7 rads/min. and 13.8 at lo8 rads/min., leading to a cal-culated value for the primary decomposition of 3.45. The irradiation ofmethane with 2 Mev electrons leads 41 to the formation of hydrogen, ethane,propane, butane, and ethylene with G values of 5.7,2-1 , 0.14,0-04, and0.05 res-pectively. The addition of benzene vapour to acetylene retards its polymer-isation 42 when irradiated with at-particles. The mean energy necessary toproduce an ion-pair when a-particles are absorbed in binary mixtures ofacetylene, methane, or benzene with other gases has been determined.43Liquids.The r61e of ion-molecule reactions in liquid-phase radiationchemistry has been discussed.@ The effects of tracks in the radiolysis ofliquids have been discussed theoretically in terms of the distribution of freeradicals.45The exchange between chlorine and carbon tetrachloride under the in-fluence of y-rays has been studied 46 by use of a radiochlorine tracer. Tworeactions were observed : the exchange of chlorine with carbon tetrachloride,and the decomposition of carbon tetrachloride to form hexachloroethaneand chlorine. y-Ray irradiation of mixtures of butyl vinyl ether and carbontetrachloride produces 47 an equimolecular addition product. The radiolysisof various alkyl iodides by y-rays has been studied 4 8 9 4 9 under varyingconditions of temperature, phase, dose rate, and oxygen concentration, and35 R.F. Firestone, J. Amer. Chem. SOC., 1957, 79, 5593.36 J . Bardwell and P. J . Dyne, Canad. J. Chem., 1957, 35, 82.37 P. Harteck and S. Dondes, J. Chem. Phys., 1957, 26, 1727.38 Idem, ibid., 1955, 23, 902.39 B. P. Burtt and A. 33. Zahlan, ibid., 1957, 26, 846.4 0 P. Harteck and S . Dondes, ibid., 1957, 27, 546.4 1 F. W. Lampe, J. Amer. Chern. SOC., 1957, 79, 1055.42 S. C. Lind and P. S. Rudolph, J. Chem. Phys., 1957, 26, 1768.43 H. J. Moe, T. E. Bortner, and G. S. Hurst, J. Phys. Chem., 1957, 61, 422.44 R. H. Schuler, J : Chem. Phys., 1957, 26, 425.45 A. Chapiro, Radzatzon Res., 1967, 6, 11.46 J. W. Schulte, J. Amer. Chem. SOC., 1957, 79, 4643.4 7 T.S. Nikitina and Kh. S. Bagdasaryan, Z h u r . 3 ~ . Khinz., 1957, 31, 704.48 E. 0. Hornig and J . E. Willard, J. Amer. Chem. SOC., 1957, 79, 2429.4 9 R. J . Hanrahan and J . E. Willard, ibid., p. 2434KINETICS OF CHBMIC.4L CHANGE. 67the results have been interpreted theoretically. The reaction of bromo-trichloromethane with alkenes under the influence of y-rays has beenstudied.50 The irradiation of a solution of acridine in alcohol with y-raysor ultraviolet radiation leads 51 to the formation of a dimer, but if bromo-trichloromethane or carbon tetrachloride is used as solvent acridine and9-methylacridine give 52 yellow insoluble products which are the correspond-ing acridinium salts of general formula Acridine,CCl,X (X = a halogen).G values for evolution of hydrogen during the radiolysis 53 of cyclohexane-benzene mixtures by y-rays have been measured with varying concentrationsof added iodine.G values for products formed in the irradiation of C, toC, rn-paraffins have been deter~nined.~~ Hexane gave hydrogen, methane,ethylene, ethane, propenes, butanes and also C, to C,, and dimeric alkanes,and unsaturated c6 hydrocarbons. The irradiation 55 of rneopentane withhigh-energy electrons leads to the formation of hydrogen, methane, andc2-c6 hydrocarbons, but n-butane gives 56 mainly mixtures of octenes andoctanes, together with some hydrogen, ethane, butene, and C,,, CI6, andCZO hydrocarbons. isoButane gives the above and also methane, propene,and large amounts of C, hydrocarbons attributed to reactions involving C,fragments.A comparison of radiolyses with 800 kev electrons and 6OCoy-rays of n-hexane has been made 57 with the use of gas-liquid partitionchromatography. C,-C,, hydrocarbons and C,, (dimer) products werefound. The polymerisation of liquid isobutene at low temperatures inducedwith electrons and y-rays has been explained 58 in terms of a mechanisminvolving carbonium ions.Irradiation of aqueous solutions of ethylene containing oxygen withX - or y-rays gave 59 hydrogen peroxide, acetaldehyde, formaldehyde,glycollaldehyde, and an unidentified organic hydroperoxide, but oxygen-freeethylene solutions gave acetaldehyde, butyraldehyde, and apparently apolyethylene. Acetylene-oxygen solutions gave mainly glyoxal.They-ray irradiation of aqueous benzene gave results 60 indicating a short chainreaction. The radiolysis by y-rays of four different deuterated ethanols hasbeen studied.61 The G values for production of hydrogen and deuterium,and the relative proportions of these two isotopes, were measured and it wasconcluded that the primary process leading to hydrogen production wasCH,*CH2*OH + CH,*cHOH + He.MeOD has been decomposed 62 by irradiation with y-rays and the5O E. A. Heiba and L. C. Anderson, J . Amev. Chewz. SOC., 1957, 79, 4940.51 A. Kellmann, J . Chim. phys., 1957, 54, 468.52 N. Ivanoff and F. Walch, ibid., p. 473.53 M. Burton, J. Chang, S. Lipsky, and M. P. Reddy, J. Cheiia. Phys., 1957, 26, 1337.54 W. H. T. Davison, Chem. and Ind., 1957, 662.56 F.W. Lampe, J . Phys. Chem., 1957, 61, 1015.56 V. J. Keenan, R. M. Lincoln, R. L. Rogers, and H. Burwasser, J . Anzer. Ch~t1.2. Soc.,5 7 H. A. Dewhurst and E. H. Winslow, J . Chem. Phys., 1957, 26, 969.58 W. H. T. Davison, S. H. Pinner, and R. Worrall, Chem. and Ind., 1957, 1274.59 P. G. Clay, G. R. A. Johnson, and J. Weiss, Proc. Chem. SOC., 1957, 96.6o P. V. Phung and M. Burton, Radiation Res., 1957, 7, 199.6L J. G. Burr, J . Amer. Chem. SOC., 1957, 79, 751.6s G. Meshitsuka, K. Ouchi, K. Hirota, and G. Kusumoto, J . Chem. SOC. Japatt,1967, 79, 5125.1987, 78, 12968 GENERAL .4ND PHYSICAL CHEMISTRY.concentration of deuterium in the liberated hydrogen determined. Themechanism of the initial stage of the decomposition has been discussed.The action of X-rays 63 on aerated aqueous ethanol gives only acetaldehyde,but in deaerated solution butane-2 : 3-diol is also produced.The ir-radiation 64 of acetic acid-oxygen solutions with 40 Mev helium ions leads tothe formation of glycollic, glyoxylic, and oxalic acids, formaldehyde, andcarbon dioxide. The electron irradiation of tri-n-butyl phosphate gives 65di-n-butyl hydrogen phosphate (G = 1-5) , n-butyl dihydrogen phosphate(G = 0.17), and gases. The y-ray induced decomposition of aqueoustetranitromethane gives 66 trinitromethane (G = 3.73). The radiolysis ofmixtures of organic liquids in the presence of diphenylpicrylhydrazyl hasbeen studied.67Solids. The y-ray induced decomposition of various solid nitrates hasbeen investigated.68 The principal products were nitrite and oxygen, theyield of the former being linear with the dose.The G values for the overalldecomposition of various solid nitrates by X-rays, corresponding to thereaction NO,- - NO,- + +02, increases 69 as the " free space " (differencebetween the volume of the crystal and the volume of the ions in it)increases. The effect 70 of electron irradiation on dianthrone and spiropyrancompounds is to produce colours similar to those produced by ultravioletirradiation.Irradiation with y-rays increases 71 the catalytic activity of alumina forthe hydrogen-deuterium exchange reaction, and of an iron oxide-potassiumcarbonate catalyst for the Fischer-Tropsch process.72Polymerisatiort . The kinetics of the polymerisation of aqueous solutionsof acrylamide initiated by X- and y-rays have been investigated 73 and theresults explained in terms of a mechanism in which termination is by mutualinteraction of growing chains, and in which the distribution of initiatingradicals is effectively uniform. The addition 74 of acidified ferric perchlorateto the above system causes linear termination of the polymerisation.Inthe y-ray induced polymerisation of acrylonitrile after-eff ects have beenobserved 75 due to the presence of long-lived free radicals.The irradiation of poly(methy1 methacrylate) solutions in L arioussolvents with y-rays 76 has been studied viscometrically and by measuringthe extent of reaction with diphenylpicrylhydrazyl. The po1,ymerisation63 G.G. Jayson, G. Scholes, and J. Weiss, J., 1957, 1358.134 W. M. Garrison, H. R. Haymond, W. Bennett, and S. Cole, J . Chem. Phys.,135 T. F. Williams, R. W. Wilkinson, and T. Rigg, Nature, 1957, 179, 540.6 6 A. Henglein and J. Jaspert, 2. phys. Chem. (Frankfurt), 1957, 12, 324.137 L. Bouby and A. Chapiro, J . Chim. phys., 1957, 54. 341.13* C. J. Hochanadel and T. W. Davis, J . Chem. Phys., 1957, 27, 333.6 9 J. Cunningham and H. G. Heal, Nature, 1957, 179, 1021.7 O Y. Hirshberg, J . Chem. Phys., 1957, 27, 758.72 R. W. Clarke and E. J. Gibson, Nature, 1957, 180, 140.'3 E. Collison, F. S. Dainton, and G. S. McNaughton, Trans. Faraday SOC., 1957,74 Idem, ibid., p. 489.7 5 R, Bensasson and A. Bernas, J . Chim. phys., 1957, 54, 479.' 6 A.Henglein, M. Roysen, and W, Schnabel, 2. phys. Chem. (FranRjurt), 1957,1956, 25, 1282.E. TY. Taylor and I€. W. Kohn, J . Amer. Chew. Soc., 1957, '99, 252.53, 476.10, 137KINETICS OF CHEMICAL CHANGE. 69has been found 77 to be slowest in benzene and more rapid in carbon tetra-chloride, chloroform, and dioxan. The radiation field for 6oCo and 137Cssources in various geometrical dispositions has been ~ a l c u l a t e d , ~ ~ and anestimate made of the yields to be expected if the sources were used to producepolymerisation.Graft copolymers have been prepared 79 by y-irradiation of polymer-monomer combinations. The block polymerisation of chlorotrifluoro-ethylene initiated by y-rays has been investigated go for doses of30-1000 rads/hr., the rate being directly related to the square root of theirradiation intensity.Theoretical discussions of the radiation-inducedchanges in polymers have been given.81382 A theoretical mechanism hasbeen suggested 83 whereby excitons formed by the irradiation of polymersmay cause cross-linking.This theory has been criticised 84 on the groundsthat the mobility of radicals may account for all the effects observed in theirradiation of polyethylene.The effects of y-ray and electron irradiation on an aqueous solution ofpoly(viny1 alcohol) ( M , 27,000400,000) have been studied 85 by use ofmeasurements of light scattering, viscosity, ultracentrifuging, and ultra-violet spectra. The observations indicated that poly(viny1 alcohol) formscross-links over the entire range of concentrations.The cross-linking and degradation of seven polyacrylates by 1000 kvpelectrons have been investigated.86 The energy dissipated for each fractureof the main chain was about 500 ev, and that for formation of each cross-linkedunit was 80-300 ev.Six different polymers were shown to be degraded 87if irradiated with X- and y-rays at low concentration, but at higher con-centrations some of them form cross-links. The effect of y-rays is to produce 88scission in poly(methy1 methacrylate) and cross-linking in polystyrene.The effects of temperature in the irradiation of polyethylene (swelling,change of sol fractions, and elasticity) have been measured 89 and the resultsinterpreted in part as clue to an increase in the number of radical-radicalreactions above the melting point.Infrared absorption measurementsindicate the formation of five- or six-membered ring systems when poly-ethylene is irradiated with y-rays. The nuclear magnetic resonancetechnique has been used Dl to study the irradiation of polyethylene with77 A. Henglein, C. Schneider, and W. Schnabel, 2. phys. Cltem. (Frankfurt), 1957,12, 339.7~ M. Magat and L. Reinisch, Internat. J . Appl. Radiation Isotopes, 1956, 1, 194.78 W. K. W. Chen, R. B. Mesrobian, D. S. Ballantine, D. J. Metz, and A. Glines,J . Polymer Sci., 1957, 23, 903.8o M. LazAr, R. Rado, and N. Kliman, Chem. Zvesti, 1956, 10, 584.81 R. W. Pearson, J . Polymer Sci., 1957, 25, 189.82 R. Simha and L. A. Wall, J . Phys. Chem., 1957, 61, 425.83 B.G. Collyns, J. F. Fowler, and J. Weiss, Chem. and Ind., 1957, 74.84 R. W. Pearson, ibid., p. 209.85 J. Berkowtich, A. Charlesby, and V. Desreux, J. P o l p e r Sci., 1957, 25, 490.8 6 A. R. Shultz and F. A. Bovey, ibid., 1956, 22, 485.s7 P. Alexander and A. Charlesby, ibid., 1957, 23, 355.s 8 L. A. Wall and D. W. Brown, J . Phys. Chem., 1957, 61, 129.8 s A. Charlesby and W. H. T. Davison, Chem. and Ind., 1957, 232.91 S. Fujiwara, A. Amainiya, and K. Shinohara, J . Chem. Phys., 1957, 26, 1343.Irradiation ofpolymers.M. Dole, D. C. Milner, a-cl T. F. Williams, J . Amer. Chem. SOC., 1957, 79, 480970 GENEKAL AND PHYSICAL CHEMISTKY.dcuterons, and also with neutrons plus y-rays. The melting behaviour ofpolyethylene after y-ray and pile irradiations has been studied.93Smoked sheet rubber, previously oriented in the calendering process, hasbeen 94 cross-linked by exposure to 2 Mev electrons in the absence of vulcan-ising agents, and subsequently showed anisotropic elastic properties.Thevulcanisation 95 of natural and synthetic rubbers by X-rays increases theelastic moduli.The irradiation of many com-pounds in this category has been studied in order to help in elucidating thecomplicated problems encountered in radiation biology.The electron and X-ray irradiation of glucose solutions 96 produces un-identified substances with characteristic absorption spectra. The ir-radiation 97 of several y-lactones leads to the formation of the correspondingascorbic acids. Thiourea 98 gives mainly free sulphur with a high G value,indicating a chain reaction.Cholesterol has been bombarded with 30 kev 14C positive ions.99 Theproducts containing radiocarbon included tram-dehydroandrosterone, carbondioxide, carbon monoxide, formaldehyde, formic acid, and oxalic acid.Asimilar experiment loo with sodium benzoate gave benzoic acid, carbonmonoxide, oxalic acid, and di-m-carboxyphenylmethane. If 14C-labelledcholesterol is stored in air, the @-particle emission leads Io1 to oxidation aboutthe 5 : 6-double bond.The self-irradiation of [35S]~~-methionine by the @-radiation gives lo2 upto twelve decomposition products detected by radiography of a chromato-gram. The X-ray irradiation of tyrosine lo3 gives 3 : 4-dihydroxyphenyl-alanine which then gives an indole derivative.Possibly the changes are thesame as those occurring during the metabolic oxidation of tyrosine to amelanin pigment. Cysteine is oxidised lO4 to a disulphoxide.The irradiation of solutions of proteins and various amino-acids leads lo5to increased optical absorption at short wavelengths (except for cystine).Gelatine gives an insoluble gel, possibly owing to cross-linking. It wasconcluded that irradiation results in rupture of carbon-carbon bonds andhydroxylation of aromatic rings.The irradiation of aqueous solutions of deoxyribonucleic acid with X-raysleads 106 to a decrease in viscosity attributed to scission of phosphate bonds.Compounds of biochemical importance.Material stored in vacuo remained unchanged.92 N.Fuschillo and J. A. Sauer, J . Chenz. Hhys., 1957, 26, 1348.93 M. Dole and W. H. Howard, J . Phys. Chem., 1957, 61, 137.94 A. Charlesby and E. von Arnim, J . Polymer Sci., 1957, 25, 151.95 A. S. Kuzminskii, T. S. Nikitina, and V. L. Karpov, Atomic Energy (U.S.S.R.),9 6 C. T. Bothner-By and E. A. Balazs, Radiation Res., 1957, 6, 302.s 7 B. Coleby, Chem. and Ind., 1957, 111.gs W. M. Dale and J. V. Davies, Radiation Res., 1957, 7, 35.gg B. Aliprandi and F. Cacace, Ann. Chim. (Italy), 1956, 46, 1204.B. Aliprandi, F. Cacace, and G. Giacomello, Ricerca sci., 1956, 26, 3029.W. G. Dauben and P. H. Payot, J . Amer. Chenz. Soc., 1956, 78, 5657.102 J. KolouSek, J. Liebster, and A. Babickf, Nature, 1957, 179, 521.J. Nosworthy and C. B.Allsopp, J . Colloid Sci., 1956, 11, 565.I o 4 R. BrdiClra and 2. Spurny, Cltenz. Listy, 1967, 51, 1267.105 RI. A. Khenokli and Y e . M. Lapinskaya, Boklady Ahad. Nauk S.S.S.K., L Y Wlo6 M. Daniels, G. Scholes, J . Weiss, and C. M. Wheeler, J . , 1957, 226.English translation, 19.56, 1, No. 3, 137; Publ. in J . Nuclear Energy, 19.57, 4, 268.110, 125KINETICS OF CHEMICAL CHANGE. 71The radiolysis of glycerophosphates has been st~died.1~7 Aqueous co-carboxylase (thiamine pyrophosphate) and thiamine show lo8 a decrease ofoptical density probably owing to attack on the chromophores by freeradicals. Hyaluronic acid depolymerises lo9 and some glucosamine isproduced. Cellulose and pectin irradiated with y-rays are degraded withloss in viscosity, both immediately and also owing to an after-effect.Ifnearly dry oxygen-free cellulose is used after-effects may be initiated ll1subsequently by admitting oxygen and terminated by the presence of water.Viscometric measurements on pectin solutions indicate 112 that irradiationcauses degradation, and that added sucrose, glucose and fructose have aprotective effect .C. F. H. T.L. H. S.A. L.F. D. S. B.THERMOCHEMISTRY.THIS Report is divided according to the main activities of thermochemistry :(i) the measurement of heats of reaction, usually divisible into (a) com-bustions, (b) reactions other than combustion; and (ii) the evaluation ofthe quantities needed to adjust heats of reaction so determined to refereither to standard-state reactions (for which all the participating substancesare in their accepted standard states) OY to gas-state reactions (for whichparticipating compounds are gaseous and participating elements gaseousatoms).These quantities include heats of fusion, vaporisation, sublimation,and atomisation.Although we emphasise work published in 1957 we try to indicate themajor developments since the last report was prepared three years ago.Many references are given in a recent review.l Certain topics are omittedeither because they have been discussed recently elsewhere, such as bondenergies by Sehon and Szwarc,2 or because they concern more the widersubject of chemical thermodynamics, such as the evaluation of thermo-dynamic functions from spectroscopy and low-temperature heat capacities.Heats of adsorption and mixing are also excluded.The former requireinterpretation in terms of current models of adsorption processes and aremore relevant to surface phenomena. Although many measurementsof the latter are reported, most of them arise from growing interest in thethermodynamic interpretation of solution phenomena (the testing of lattice-model and other theories) and are not of immediate thermochemical value.The elements have been the subject of a notable book.3Heats of Combustion.-Measurements of heats of combustion provide thelo’ G. Scholes, W. Taylor, and J. Weiss, J , , 1957, 235.lo* M. Ebert and A. J. Swallow, Radiation Res., 1957, 7, 220.log A. Caputo, Nature, 1957, 179, 1133.R. E. Clegg and 2. I. Kertesz, Science, 1956, 124, 893.ll1 R.E. Clegg, Radiation Res., 1957, 6, 469.112 Z. I. Kertesz, B. H. Morgan, L. W. Tuttle, and M. I-avin, ibid., 1956, 5, 372E. F. Westrum, Ann. Rev. Phys. Clzem., 1957, 8, 1.A. H. Sehon and M. Szwarc, ibid., p. 439.D. R. Stull and G. C. Sinke, “ The Thermodynainic Properties of the Elements,”Amer. Chem. SOC., Washington, 195672 GENERA41, AND PHYSICAL CHEMISTRY.most general method of determining heats of formation, but the combustionproducts must be definable thermochemically with precision. This hasbeen relatively easy for hydrocarbons and compounds containing carbon,hydrogen, ar,d oxygen only, and in the past decade the difficulties presentedby organic compounds containing nitrogen or sulphur have been largelyo~ercome.~ Considerable progress has also been made in the reliabilityof the combustion of organic chlorine-, bromine-, and iodine-containingcompo~nds.~ Compounds containing other elements have not yet beenstudied successfully.Recently, however, noteworthy advances have beenachieved for organic fluorine-containing and certain organometallic com-pounds (see p. 73); this progress has been largely dependent upon themoving-bomb technique, the most versatile and reliable method yet devisedfor extending accurate combustion calorimetry to groups of compounds notaccessible by conventional methods.Hydrocarbons. Since the appearance of the revised edition of the,4merican Petroleum Institute Research Project 44 tables in 1954 severalsheets of new or revised data have become available; these do not call forcomment.Day and Oestrich have measured heats of combustion andderived the resonance energies of dimethyl- and diphenyl-fulvene.Compounds containkg carbon, hydrogen, and oxygen. A noteworthypaper by Coops et aL7 summarises work begun 20 years ago on the deter-mination of the absolute heat of combustion of benzoic acid. The latestvalue quoted by these authors (26,435 J/g.) is compared with their earlierone (26,438 J/g.) and with those of other workers. The agreement betweenthe various investigations is good, the total " spread " being about 0.02%.From heats of combustion Jaffe, Prosen, and Szwarc deduced values of-127.9, -148.2, and -161 kcal./mole for the heats of formation of liquidacetyl, propionyl, and butyryl peroxides, and values of -45, -54, and-60 kcal./mole for the heats of formation of the acetate, propionate, andbutyrate radicals.Briner and Dallwigk have determined the heat ofcombustion (- 1697 kcal./mole) of the ozonide of trans-stilbene and deducedits heat of formation (-102) and heat of scission (84.5 kcal./mole). Nichol-son 10 has measured the heat of combustion of acetylacetone and obtaineda value in good agreement with that calculated by Kharasch.llOrganic nitrogen-containing compomds. Heats of combustion forthirteen explosives including nitro-compounds , nitrates, and nitramines l2and thirty-six triazoles , tetrazoles , and related high-nitrogen compounds l3have been reported. Some of these compounds could not be made to burnsmoothly or completely. Heats of combustion of liquid ethyl, rc-propyl," Experimental Thermochemistry ", ed.by F. D. Rossini, Interscience, New York,J. H. Day and C. Oestrich, J . Org. Chem., 1967, 22, 214.J. Coops, N. Adriaanse, and K. van Nes, Rec. Trav. chim., 1956, 75, 237.L. Jaffe, E. J . Prosen, andM. Szwarc, J . Chern. Phys., 1957, 27, 416.E. Briner and E. Dallwigk, Helv. Chinz. Acta, 1957, 40, 1978.1956, chaps. 6 and 7.5 See ref. 4, chaps. 8, 9, and 10.l o G. R. Nicholson, J., 1957, 2431.l1 M. S. Kharasch, Bur. Stand. J . Izes., 1929, 2, 359.l2 L. Medard and M. Thomas, Me'm. Pmdres, 1957, 38, 45.13 M. M. Williams, W. S. McEwan, and R. A. Henry, J . Phys. Chem., 1957, 81, 261MACKLE : THERMOCHEMISTRY. 73and isopropyl nitrates have been determined and the corresponding heatsof formation derived.14Smith l5 has published a tableof heats of combustion of twenty organic iodine compounds.These arebased, after small corrections, upon unpublished work by K. J. Karlsson.16Good, Scott, and Waddington17 have continued their study of thecombustion of organic fluorine compounds and established the generalreliability of their method. They report heats of combustion and formationfor six compounds selected to include volatile liquids, non-volatile solids,a group of isomers, and compounds with a wide range of fluorine content,namely o-, m- , and p-fluorobenzoic acids, fluorobenzene , benzotrifluoride ,and polytetrafluoroethylene : p-fluorobenzoic acid is suggested as a referencesubstance for the intercomparison among different laboratories of bomb-calorimetric data for fluorine compounds. Neugebauer and Margrave l8have determined the heats of combustion and formation of 1 : l-difluoro-ethylene with a conventional bomb calorimeter.Organometallic compounds.In an important paper on the heat ofcombustion of tetraethyl-lead Scott , Good, and Waddington l9 haveillustrated the power of the method of rotating-bomb calorimetry whenapplied to a problem involving hitherto intractable chemical, equilibration,and correction difficulties. The complex mixture of Pb, PbO, Pb,O,,PbO,, and other lead compounds produced by the combustion was convertedquantitatively into Pb2+ ion in solution by 2~-nitric acid containing a littlearsenious acid.The relatively large volume of final solution was quicklyrendered homogeneous and in equilibrium with the gas phase by rotatingthe bomb. Fairbrother and Skinner 2o have measured the heat of com-bustion and deduced the heat of formation of diphenylmercury ; theirresults differ significantly from earlier onesJ21 but are supported by indepen-dent heat of reaction data.,,In the combustion of trimethyl-arsine Long and Sackman 23 experienced difficulties of incomplete com-bustion and oxidation similar to those encountered with trimethyl-bismuthand -antimony.% The reliability of their values for the heats of combustionand formation depends, therefore, upon accurate analysis of the combustionproducts, which they claim to have achieved.More recently 25 they reporteddata for trimethylphosphine, and discussed the values derived for themean dissociation energies of the P-C, As-C, Sb-C, and Bi-C bonds. AOrganic halogen-containing compounds.Miscellaneous organic compounds.l4 D. M. Fairbrother, H. A. Skinner, and F. W. Evans, Trans. Faraday SOC., 1957,l5 L. Smith, Acta Chem. Scand., 1956, 10, 884.l8 K. J. Karlsson, Thesis, Lund, 1941.l7 W. D. Good, D. W. Scott, and G. Waddington, J . Phys. Chern., 1956, 60, 1080.la D. W. Scott, W. D. Good, and G. Waddington, J . Phys. Chem., 1956, 60, 1090.2o D. M. Fairbrother and H. A. Skinner, Trans. Faraday Soc., 1956, 52, 956.21 A. S. Carson, E. M. Carson, and B. R. Wilmshurst, Nature, 1952. 170, 320.22 C. L. Chernick, 13.A. Skinner, and I. Wadso, Trans. Faraday Soc., 1956, 52, 1088,23 L. H. Long and J. F. Sackman, ibid., p. 1201.Z4 Idem, ibid.. 1954, 50, 1177; 1955, 51, 1062.25 Idem, ibid., 1957, 53, 1606.53, 779.C. A. Neugebauer and J. L. Margrave, J . Phys. Chem., 1956, 60, 1318; J . Amer.Chem. SOC., 1957, 79, 133074 GENERAL AND PHYSICAL CHEMISTRY.notable gap is the continued lack of precise information on the heats ofcombustion and formation of the parent of the series, trimethylamine.Clarke and Datta 26 have reported values for the heats of combustion ofglycerol 1-(disodium phosphate), glycerol 2-(disodium phosphate), andglucose l-(disodium phosphate). These cannot, however, be accepted asvery reliable, mainly because of the absence of any serious attempt toanalyse the combustion products.Handrick 27 has described yet anothermethod for doing this: it involves the principle of the summation of group,as distinct from bond, energies.A practical feature is the claim that itcan predict explosive properties. A treatment, similar in principle butrather simpler, has been devised by Young et aL28 for organic nitrogencompounds and appears to give fairly reliable results.Inorganic substances. Accurate measurements of the heats of com-bustion of pure calcium, dysprosium, ytterbium, erbium, holmium, andyttrium 29 are reported. For calcium it was necessary to work a t 50 atm.pressure, as otherwise the amount of unburnt metal was quite large. Theremaining metals were readily burnt at the usual oxygen pressure of 25 atm.The heats of formation of the oxides formed have been deduced. Fischeret aL30 measured the heats of combustion of chromium, molybdenum,tungsten, and nickel carbonyls.The results, when combined with knownthermochemical data, give reliable estimates of the heats of formation ofthe solid carbonyls. The paper on nickel carbonyl reports an interestinginternal firing technique for volatile liquids. Mah 31 has reported valuesof -400.5, -178.2, and -140.6 kcal./mole respectively for the heats offormation of alumina, molybdenum trioxide, and molybdenum dioxide.These are all in good agreement with those of earlier workers.Reactions other than Combustion.-Despite their great thermochemicalvalue, the use of combustion reactions is often precluded. For instance,the chemistry of most combustions involving compounds containingphosphorus, boron, silicon, arsenic, or metals needs much clarificationand control before the heat changes associated with them can be reliablydetermined. Fortunately there are a variety of other reaction types whichcan be used to provide precise thermochemical data for such com-pounds, including hydrogenation and reduction, halogenation, hydrolysis,and miscellaneous reactions.Most noteworthy among therecent contributions to the calorimetry of gas-phase hydrogenation arethose of Lacher and his co-workers32 who have obtained highly reliableCalculation of heats of combustion.Heats of hydrogenation and reduction.26 H.B. Clarke and S. P. Datta, Biochem.J., 1957, 66, 451.2 7 G. K. Handrick, Ind. Eng. Chem., 1956, 48, 1366.28 J. A. Young, J. E. Keith, P. Stehle, W. C. Dzombak, and H. Hunt, ibid., p. 1375.29 E. J. Huber, E. L. Head, and C. E. Holley, J . Phys. Chern., 1956, 60, 498, 1457,30 A. K. Fischer, F. A. Cotton, and G. Wilkinson, J . Amer. Chem. Soc., 1956, 78,31 A. D. Mah, J . Phys. Chem., 1957, 61, 1572.32 J. R. Lacher, E. Emery, E. Bohmfalk, and J . D. Yark, ./. Phys. Chem., 1956, 60,492; J. R. Lacher, A. Kianpour, and J. D. Park, 1454; J. R. Lacher, A. Kianpour,P. Montgomery, H. Knedler, and J. D. Park, 1957,61, 1125; J. R. Lacher, A. Kianpour,F. Oetting, and J. D. Park, Trans. Faraday SOC., 1956, 52, 1500.1582; 1957, 61, 497, 1021.6168; 1957, 79, 2044MACKLE : THERMOCHEMISTRY.75data for the heats of hydrogenation of a wide range of organic bromides,chlorides, and fluorides. A palladium-charcoal catalyst is used for thehydrogenation and the heat quantities are determined in a specially con-structed isothermal flow-calorimeter of high accuracy. The heats ofhydrogenation of CH,CI, C,H,Cl, C2H,C1, n-c3H,F, iso-C3H,F, CF,=CFCI,CF,=CHCl, CF,=CCl,, and CH,=CHBr are reported, and in several instancesthe corresponding heats of formation have been deduced. The heat offormation of hydrogen bromide from the gaseous elements has beenmeasured directly for the first time and the value obtained supports thecurrently accepted indirect value.33 In the course of this work the lowermembers of a homologous series proved more difficult to hydrogenate thanthe higher. The lower fluoro-compounds provide the extreme example inthis respect ; the hydrogenation of methyl and ethyl fluorides and perfluoro-vinyl bromide has not yet been made sufficiently quantitative to permitcalorimetry.In a series of papers Turner et ~ 1 . ~ ~ have reported the heatsof platinum oxide-catalysed hydrogenation in acetic acid solution ofbicyclo[2 : 2 : llheptene, bicyclo[Z : 2 : llheptadiene, bicyclo[2 : 2 : Sloctene,bicyclo[2 : 2 : 2]octadiene, cyclooctatetraene, some seven-membered non-benzenoid aromatic compounds, some unsaturated steroids and some cis-and tram-cycloolefins. The results illuminate a number of theoreticalquestions including the relative importance of angle strain and non-bondedrepulsions in the bicycloheptene and bicyclooctene systems ; the stabilityrelationships among olefins possessing double bonds at different positionsin a fused ring system; and the energetic interpretation of the directionalspecificity of certain enol reactions.They also indicate that there is no“ homoallylic resonance ” stabilisation in bicycloheptadiene and lead tovalues of 2.4, 0.9, 28, 13, and 28 kcal./mole for the resonance energies ofcyclooctatetraene, 1 : 3 : 5-cyclooctatriene, azulene, heptafulvene, and hepta-fulvalene respectively. Ideally, of course, resonance energies should beevaluated from gas-phase measurements and the above values are subjectto uncertainties introduced by solvation and other effects. Turner andGarner 35 measured the heats of hydrogenation in acetic acid of 1-methyl-cydohexene, methylenecyclohexane, 1-methylcyclopentene and methylene-cyclopentane and showed that the methylcycloalkenes are the more stableisomers.The effect of alkyl substituents on the heats of hydrogenation of olefinshas been commonly attributed to hyperconjugation alone.Often, however,the resulting hyperconj ugation energies have appeared rather large whencompared with the conjugation energies obtained for unsaturated substituents.This anomaly has been discussed by Taft and Kreevoy36 who point outthat hyperconjugation is not the only contributing influence. The hydro-genation of a double bond markedly decreases the intrinsic electronegativity33 “ Selected Values of Chemical Thermodynamic l’roperties,” Series 111, NationalHureau of Standards, Washington.34 R.B. Turner, W. R. Meador, and K. E. Winkler, J . Anier. Chem. SOC., 1957, 19.4116,4122; R. B. Turner, W. R. Meador, W. von E. Doering, L. H. Knox, J. R. Mayer,and D. W. Wiley, ibid., p. 4127; R. B. Turner and W. R. Meador, ibid., p. 4133.36 R. B. Turner and R. H. Garner, ibid., p. 253.36 R. W. Taft and M. M. Kreevoy. ibid., pp. 4011, 401676 GENERAL AND PHYSICAL CHEMISTRY.of its atoms, for the sp2 valence state is appreciably more electronegativethan the sp3. It is plausible, therefore, that, in addition to hyperconjugation,polar or inductive effects contribute significantly to the observed influenceof a-saturated substituents on heats and free energies of hydrogenation.Taft and Kreevoy have devised additivity equations by which the hyper-conjugation and inductive effects can be estimated separately; the relativemagnitudes of hyperconjugation and conjugation effects then appearreasonable.The average conjugation effect is about ten times the hyper-conjugation effect of an a-hydrogen atom.Flitcroft, Skinner, and Whiting 37 have designed a calorimeter speciallysuited to the measurement of heats of hydrogenation in solution. Animportant point is that the reaction vessel is mechanically shaken. Theheats of hydrogenation of hex-l-ene, fumaric acid, maleic acid, dodeca-3 : 9-diyne, dodeca-5 : 7-diyne, and octa-1 : 7-diyne are reported. A value of10 kcal./mole is deduced for the overall conjugation energy of the system-CEC-CEC-.Neugebauer and Margravela have measured the heats offormation of CF,, C,F,, and C10,F by hydrogenation and decompositionin a bomb calorimeter. Their result (151.7 kcal./mole) for C,F, agrees wellwith that of D U U S ~ ~ but differs considerably from those of von Warten-berg39 and Kirkbride and D a v i d ~ o n . ~ ~ Their result for CF4 supports thatof Scott, Good, and Waddingt~n.~l Hill and Williamson 42 have derivedthe heat of formation of potassium manganate in solution by measuringthe heat of reduction of potassium permanganate by hydrogen peroxide.Recently heats of formation of organic chloro-compounds have been derived mainly from the combustion studies ofSmith and his co-workers at Lund and the U.S. Bureau of Mines Group atBartle~ville.~~ Where comparison can be made, the results of these twoschools generally agree, but as they employ basically the same techniquesome independent check has been needed.KirkbrideU has recentlysupplied this in a valuable paper on the calorimetry of both substitutiveand additive chlorination of hydrocarbons. He has determined directlythe heats of substitutive chlorination (RH + C1, + RC1 + HC1) forbenzene, chlorobenzene , toluene, cyclohexane, .ia-hexane, ethylene dichloride ,and chloroform and derived the heats of formation of 1 : 1 : S-trichloro-ethane, chlorocyclohexane, and benzyl chloride; and the heats of additivechlorination of cis-dichloro-, trichloro-, and tetrachloro-ethylene. Thechlorinations were carried out by bubbling chlorine gas through a speciallyconstructed reaction vessel immersed in a Dickinson-type calorimeter.For substitutive chlorinations in the aromatic nucleus anhydrous ferricchloride was used as catalyst.All other chlorinations were photoactivated.Kirkbride's results confirm the reliability of modern methods of combustioncalorimetry of organic chloro-compounds. They also support the value37 T. Flitcroft, H. A. Skinner, and M. C. Whiting, Trans. Faraday SOC., 1957,53, 784.a* H. C. Duus, Ind. Eng. ChePn., 1955,47,1445.3s H. von Wartenberg, 2. anorg. Chem., 1955, 278, 326.40 F. W. Kirkbride and F. G. Davidson, Nature, 1954, 174, 79.41 D. W. Scott, W. D. Good, andG. Waddington, J . Amel.. Chem. SOC., 1955, 77, 845.42 R. A. IV.Hill and J. F. Williamson, J., 1957, 2417.43 See H. A. Skinner, Ann. Reports, 1954, 51, 36.44 F. W. Kirkbride, J . Appl. Chem., 1956, 25, 519.Heats of halogenationMAC KLB THE RMOCIl E M I STHY . 77(-30.2) quoted by Smith et ~ 1 . ~ ~ for the heat of formation of carbon tetra-chloride. This is about 3 kcal./mole lower than the value quoted in theNational Bureau of Standards Circular 500. Finally, Kirkbride's value(32 kcal./mole) for the heat of chlorination of gaseous tetrachloroethylenemay be compared with that (-30) previously estimated from e q ~ i l i b r i a . ~ ~Ito's more recent value*' appears to be seriously erroneous. Lacheret ~ 1 . ~ ~ have measured the heats of vapour-phase addition bromination oftetrafluoro- and chlorotrifluoro-ethylene with ferric bromide and antimonybromide as catalysts, and of addition chlorination of perfluorinated but-l-ene, isobutene, and pent-l-ene with ferric chloride on activated carbon ascatalyst.The data obtained, together with those previously reported,49show that the heats of bromination and chlorination of a double bond aregreatly influenced by the substituents on its carbon atoms; variations upto 20 kcal./mole occur. The same authors 50 have redetermined the heatsof hydrobromination of propene and cyclopropane and found values of20-4 and 25.8 kcal./mole respectively. The latter is about 3 kcal./molehigher than their previous value. Benson and from equilibriumstudies of the side-chain bromination of toluene, have obtained a value of-20 kcal./mole for the heat of formation of benzyl bromide; this is about 6kcal./mole greater than that derived from kinetic studies by several authors,notably Szwarc, and it is contended that certain interpretations of the kineticdata have been oversimplified. Szwarc has replied to these criticisms.Skinner and his co-workers 52 have measured the heats of reaction ofbromine vapour with liquid tetramethyltin and of bromine and iodine withhexamethylditin and derived values of -41-4 & 11, -28.2 & 11, and-23.3 5 22 kcal./mole respectively for the heats of formation of gaseous(CH,),SnBr, (CH,),SnI, and (CH,),Sn2.The large error limits are due to anuncertainty of *lo kcal./mole in the only available value for the heat offormation of tetramethyltin.This uncertainty is due mainly to incompletecombustion of the metal alkyl. The heat of formation of titanium tetra-bromide has been derived independently by two groups 53 from the heatof bromination of titanium. Gross, Hayman, and Levi 53 have also revisedtheir earlier value for the heat of formation of titanium tetrachloride andreported a value for the heat of formation of zirconium tetrachloride.%Hydrolyses usually proceed cleanly and quantita-tively and are frequently used in thermochemistry. Sunner and Wadso 55have measured the heat of hydrolysis and deduced the heat of formation45 L. Smith, L. Bjellerup, S. Krook,and H. Westermark, Acta Chenz. Scand., 1953,7,65.413 K. J. Ivin and F. S. Dainton, Trans. Faraday Soc., 1947, 43, 32.47 J.Ito, Univ. Colorado Stadies, 1954, 29, 83,4 8 J. R. Lacher, L. Caseli, and J. D. Park, J . Phys. Chem., 1956, 60, 608; J. R.Lacher, A. Kianpour, and J. D. Park, ibid., 1957, 61, 584.4 0 J. R. Lacher, J. J. McKinley, C. M. Snow, L. Michel, G. Nelson, and J. D. Park,J . Amer. Chenz. Soc., 1949, 71, 1330; J. R. Lacher, J, J. McKinley, C. Walden, K. Lea,and J. D. Park, ibid., p. 1334.5 0 J. R. Lacher, A. Kianpour, and J. D. Park, J . Phys. Chem., 1957, 61, 1124.5L S. W. Benson and J. H. Buss, J . Phys. Ghem., 1957, 61, 104.53 J . B. Pedley, H. A. Skinner, and C. L.Chernick, Trans. Faraday Soc., 1957,53,1612.53 H. L. Schlafer and H. H. Smidtke, 2. phys. Chem. (Frankfurt), 1957, 11, 297;54 I d e m , ibid., p. 1285.55 S. Sunner and I, Wadso, ibid., p.455.Heats of hydrozysis.P. Cross, C. Hayman, and D. L. Levi, Trans. Faraday Soc., 1957, 53, 160178 GENE K A 1, il N L) PI3 YSI CA 1, C l i IS M I STKY.of thiolacetic acid. Their value for the latter (-52.3) may be comparedwith that (-51.5 kcal./mole) derived from heats of comb~stion.~6 Hearneand White 57 have measured the heat of solution of uranium tetrachloridein aqueous hydrochloric acid-lithium chloride mixtures at constant ionicstrength. The observed variation of this quantity with the hydrochloricacid concentration conflicts with current views on the hydrolysis of theuranium(1v) ion. The authors conclude that any attempt to derive heatsof hydrolysis from heats of solution is liable to be seriously misleadingunless adequate data are available from which the effect of the medium onthe heats of solvation of the ions can be evaluated.Flitcroft and Skinner 58have measured the heats of hydrolysis of ethyl orthosilicate and chloro-triethylsiloxane and derived the corresponding heats of formation. Theheat of the gaseous redistribution reaction between ethyl orthosilicate andsilicon tetrachloride to form chlorotriethoxysilane is estimated to be 4.3kcal./mole. Other thermochemical data derived from heats of hydrolysisinclude the heats of formation of Na202, NaO,, and K02,59 nitramide,60and cyanuric chloride.6l The last result leads to a new value for the heatof trimerisation of cyanogen chloride. The heats of hydrolysis of adenosinetriphosphate 62 and hydroxylamine hydrochloride 63 have also been reported;the former is a reaction of great importance in biological energy transfers.Heats of miscellaneous reactions. Considerable attention has beengiven recently to the energetics of formation of complexes and co-ordinationcompounds.As part of an extended investigation of steric effects in dis-placement reactions Brown and Gintis measured the heats of reaction ofgaseous trimethylboron and diborane with pyridine bases in nitrobenzenesolution. The calorimetric system described is of general interest in thatit is specially suited to work where one reactant is gaseous and the otherliquid. From the difference in the heats of reaction of trimethylboronwith the 4- and the 2-alkylpyridines it can be inferred that a steric strainof about 6 kcal./mole exists in 2-picoline, thus supporting the predictionby Brown et aE.65 of strains of this magnitude for all homomorphs of o-tert.-butyltoluene.Brown and Holmes 66 claim to have shown, contrary tosuperficial expectation, that the relative strengths of the boron halides asLewis acids decrease in the order BBr, > BCI, > BF,. Their conclusionsare based on measurement of the heats of formation of the 1 : 1 molecularcomplexes of the boron halides with pyridine and nitrobenzene. It appearsthat resonance contributions play a dominant r81e in determining therelative acceptor properties of the boron halides. McCoy and Bauer 6756 S. Sunner, Ada Chem. Scand., 1955, 9, 847.5 7 J. A..Hearne and A. G. White, J., 1957, 2081.5* T.Flitcroft and H. A. Skinner, J., 1956, 3355.6s P. W. Gilles and J . L. Margrave, J . Phys. Chew$., 1956, 60, 1333.60 J. D. Ray and R. A. Ogg, ibid., p. 1460.62 R. J. Podolsky and M. F. Marales, J. BZoZ. Chern., 1956, 218, 946.63 S. S. Muhammad, D. H. Rao, and M. A. Haleem, J. Indian Chern. Suc., 1957,34,101.84 H. C. Brown and D. Gintis, J. Amer. Chern. SOC., 1956, 78, 5378, 5384.H. C. Brown, G. K. Barbaras, H. L. Berneis, W. H. Bomer, R B. Johannesen,H. C. Brown and R. R. Holmes, ibid., 1956, 78, 3173-A. R. Humphries and G. R. Nicholson, J., 1957, 2429.M. Grayson, and K. L. Nelson, ibid., 1953, 75, 1.s7 R. E. McCoy and S . H. Bauez, ibid., p. 2061~r.ux~x : THBKMOCHEMISTRY. 79have estimated the bridge-breaking energy of diborane based on the heatsof reaction of (i) trimethylboron with ammonia and the methylamines, (ii)diborane with the methylamines, and (iii) tetramethyldiborane with tri-methylamine.Their value, 28 3: 2 kcal./mole, is subject to certainassumptions. The heats and entropies of combination of various alkaline-earth ions with the ligand anions of ethylenediaminetetra-acetic acid,nitrilotriacetic acid, etc., have been derived by Martel 68 from cell measure-ments of dissociation constants. These studies supplement earlier ones 69and the most significant general feature of the accumulated data is that thestabilities of the chelate compounds are due almost entirely to a favourableentropy increase, the enthalpy changes being relatively unimportant.These general conclusions are supported by direct calorimetry by Charles 70and by Care and S t a ~ e l e y , ~ ~ but the detailed results of the latter workersthrow doubt on the overall reliability of the AH values obtained by Martel'smethod.The energies and entropies of the molecular association of amidesin benzene have been reported by Davies and Thomas.72 The hydrogen-bridge energy is found to be 3.6 kcal./mole in all cases. From optical-density estimations of equilibrium constants at different temperaturesBier 73 has estimated the heats of complex-formation of s-trinitrobenzenewith a series of aromatic hydrocarbons and aromatic amines. These liewithin the range 0.45 to 3 kcal./mole and depend, as might be expected,upon the degree of electron-donating substitution of the benzene ring.Thermodynamic studies of solutions of iodine in solvents with which itforms molecular complexes have been reported by Jepson and Rowlinson. 74The heats of solution calculated from solubility-temperature measurementsagree well with those determined directly.75 The complex-forming powerof the various solvents appears to increase in the following order : paraffins <halogenobenzenes < benzene < mesitylene < ethyl bromide < ethylether < pyridine < ethyl iodide. Chernick et aZ.76 have measured theheats of addition of rhombic sulphur to triethyl phosphite and tri-n-propyl-and tri-n-butyl-phosphine, and deduced values for the dissociation energiesof the thiophosphoryl bonds, S=PR,. If*the value chosen by the authorsfor AH&,) is correct, these all lie close to 91 kcal./mole.The nature of Rappears to have no appreciable effect on D(S=PR,). Compounds in whichphosphorus, arsenic, or antimony forms a direct donor-acceptor bond togallium afford another means of studying the interplay of several factorson bond strength. The energies involved in the molecular addition reactionsbetween GaCl, and POCl, and GaC1, and PCl, have been measured recentlyby Greenwood et al.; 77 this work necessitated the design of an all-glass68 A. E. Martel, Rec. Trav. chinz., 1956, 75, 781.6 8 F. F. Carini and A. E. Martel, J . dmer. Chenz. Sor., 1952, 74, 5745; 1953, 75,7 0 R. G. Charles, ibid., p. 5854.73 M. Davies and D. K. Thomas, J . Phys. Chem., 1956, 80, 763, 767.73 A.Bier, Rec. Trav. chirn., 1956, 75, 866.74 W. B. Jepson and J. S. Rowlinson, J . , 1956, 1279.7 5 K. Hartley and H. A. Skinner, Trans. Faraday SOC., 1950, 46, 621.7 6 C. L. Chernick, J . B. Pedley, and H. A. Skinner, J., 1957, 1851.7 7 N. N. Greenwood and P. G. Perkins, J . Inorg. Nuclear Chewz., 1957,. 4, 291;4810; 1954, 76, 2153.R. A. Care and L. A. K. Staveley, J . , 1956, 4571.N. N. Greenwood, P. G. Perkins, and K. Wade, J . , 1957, 434580 GENERAL AND PHYSICAL CHEMISTRY.precision calorimeter suitable for work with hygroscopic or reactive sub-stances in an inert atmosphere. The small value (3.4 kcal./mole) for theheat of the reaction between GaCl, and PCl, implies that the complexCl,Ga+PCl, is not very stable. The gas-phase heat of formation of theGaCl,,POCl, complex is 22.6 kcal./mole.This gives some indication ofthe Cl+Ga bond strength.Other thermochemical studies reported include the thermal decom-position of silane at 680" in a flow cal~rimeter,~~ the results of which supportthe lower values for the heat of formation of silane; the heat of the gas-phase reaction between dinitrogen pentoxide and nitric oxide, leading to avalue of -3 kcal./mole for the heat of formation of gaseous dinitrogenpentoxide; 79 the heats of a number of semiacetalisation reactions;the dissociation energy of indium phosphide; the heats of reaction withdilute hydrochloric acid of Sr3P2, Li,Bi, Ba,Bi,, BaBi, Li,As, Mg,As,, andZn,As, from which are deduced values of -160, -39, -128, -40, -81,-96, and -30 kcal./mole respectively for the heats of formation of thesecompounds; 8, the estimation from electron-impact studies of the heat offormation of the C2H radical and the energies of the C'C and C-H bonds inacetylene and of several bonds in substituted acetylenes; 83 the heats of for-mation of the aqueous oxide ions of americium, AmO,+(aq) and Am0,2+(aq),from microcalorimetric measurements ; the heat of formation of aluminiumnitride by direct nitridation in a bomb calorimeter ; 85 the heats of formationof NaA10, and LiA10,; 86 and the ortho- and meta-silicates of barium andstrontium, dibarium trisilicate, and barium di~ilicate.~~ Muldrow andHepler s8 have determined the heats of solution in water or dilute aqueousperchloric acid of K2Cr207, K,CrO,, and (NH,),Cr,O, and the heats ofreaction of K,Cr,O, and CrO, with aqueous alkali and of K2Cr0, withaqueous acid.From the results the heats of formation of K,CrG,, K2Cr,07,(NH,),Cr,O,, (Cr0,2-) (as) and (Cr207,-) (aq) are derived. With theexception of the value for ammonium dichromate these heats of formationappear more reliable than any previously published. The value (-425)for (NH4),Cr20, may be contrasted with that (-429) recently reported byNeugebauer and Margrave s9 and with that (-430 kcal./mole) derivedfrom heats of combusti~n.~~ It is, however, based on a value of -138for the heat of formation of CrO,, whereas Neugebauer and Margrave 897 8 E. 0. Brimm and H. H. Humphreys, J . Phys. Chem., 1957, 61, 829.7 B J.D. Ray and R. A. Ogg, ibid., p. 1084.M. Bakes, Compt. rend., 1957, 244, 2726.K. Weiser, J . Phys. Chem., 1957, 61, 513.82 S. A. Shchukarev, M. P. Morozova, and Kho-yn Kan, Zhur. obshchei Khirn., 1957,27, 289; S. A. Shchukarev, M. P. Morozova, Kho-yn Kan, and V. T. Sharov, ibid., p.290; S. A. Shchukarev, M. P. Morozova, Kho-yn Kan, Tszi-Tao Kuan, and E. Vol'f,ibid., p. 293.8a F. H. Coats and R. C. Anderson, J . Amer. Chem. SOC., 1957, 79, 1340.84 S. R. Gunn and B. B. Cunningham, ibid., p. 1563.85 C. A. Neugebauer and J. L. Margrave, see ref. 18.8 6 J. P. Coughlin, J . Amer. Chenz. SOC., 1957, 79, 2397.87 R. Baranay, E. G. King, and S. S. Todd, ibid., p. 3639.88 C. N. Muldrow and L. G. Hepler, ibid., p. 4045.so A. F. Kapustinski, A.A. Shidlovskii, Izvest. Sekt. Platiny i Drug. Blagorod MetalInst. Obshchei i Neorg., Akad. Nauk S.S.S.R., 1956, 30, 31,C. A. Neugebauer and J. L. Margrave, J . Phys. Chem., 1957, 61, 1429MACBLE : TIIERMOCHERIISTRY. S lassert that the correct value for the latter is -142 kcal./mole. Price andTrotman-Dickenson,gl from studies of the rate of pyrolysis of (CH,) 2Hg,(CH,) ,Cd, and (CH,),Zn, have deduced values for the bond-dissociationenergies, D(CH,-MCH,) and D(CH3-M-) where M is Hg, Cd, and Zn. Theseare 50 and 7 for the compounds of mercury, 46 and 21 for those of cadmiumand 47 and 35 kcal./mole for those of zinc. Dainton and his co-workers 92used an isothermal fusion calorimeter to measure the heats of copoly-merisation of sulphur dioxide with certain olefins..These correlate wellwith the corresponding heats of hydrogenation except for cyclopentenewhich has the lowest heat of hydrogenation but the highest heat of copoly-merisation; this discrepancy is discussed. The present results point to avalue of about 81 kcal./mole for the sum of the two carbon-sulphur bonddissociation energies in polysulphones ; other data indicate that the corre-sponding quantity in dimethyl sulphone is 80 kcal./mole. The heats offormation of twenty-six substances, mainly ureas and diphenylamines,have been reported.g3 Goton and Whalley 94 have critically reviewedliterature data for various thermodynamic properties of benzoic acid.They recommend a value of -380,140 -& 290 abs. joules mole-1 for theheat of formation at 2 5 " ~ .A most important development in alloythermochemistry was the introduction of the method of tin-solutioncalorimetry by Ticknor and Bever 95 which has proved capable of providingfar more accurate data on the heats of formation of solid binary alloys thanhad hitherto been possible. During the past three years it has been notablyexploited by Kleppa 96 and Kleppa and Kaplan 96 who reported the heatsof formation of the following alloys : tin-rich binary and ternary alloys, liquidalloys of copper, liquid mercury-indium alloys, and solid alloys of gold withcadmium, indium, tin, and antimony.Heats of Fusion, Vaporisation, Sublimation, and Atomisation.-Among themost intractable problems of chemistry during the last few decades havebeen those of obtaining unambiguous values for the heats of dissociationof nitrogen and carbon monoxide and the heat of sublimation of carbon.Various authors at different times have recommended widely differentvalues for these q~antities.~' In the past two or three years, however,more evidence in support of the higher values has acc~mulated.~~ Byelectron-impact studies with use of essentially monoenergetic electronsBurns 99 and Clarke loo have arrived at a value of 9.65 ev for D(N,) andtheir work has been confirmed by Frost and McDowell.lO1 By a similar91 S.J. W. Price and A. F. Trotman-Dickenson, Tvans. Favaday Soc., 1957, 53,939, 1208.92 F. S. Dainton, J. Diaper, K. J . Ivin, and D. R. Sheard, ibid., p. 1269.93 P. Tavernier and M.Lamouroux, Mdm. Poudres, 1957, 38, 65.94 R. Goton and E. Whalley, Canad. J . Chern., 1956, 34, 1506.85 L. B. Ticknor and M. B. Bever, J . Mefals, 1952, 4, 941.9 6 0. J. Kleppa. J . Phys. Chem., 1955, 59, 175, 354; 1956, 60, 446, 842, 846, 852,858; 0. J. Kleppa and M. Kaplan, ibid., 1957, 61, 1120.97 See refs. 2 and 43.g8 L. Brewer and A. W. Searcy, Ann. Rev. Phys. Chem., 1956, 7, 259.J. F. Burns, J . Chew. Phys.. 1955, 23, 1347.loo E. M. Clarke, Canad. J . Phys., 1954, 32, 764.l o 1 D. C. Frost and C , A. McDowell, Proc. Roy. SOC., 1956, A , 236, 278.The thermochemistry of alloysmethod, Lagergrenlo2 has concluded that 11.1 ev is the correct value forD(C-0) and this is supported by Brackett's work.lo3 In a most importantpaper Chupka and Inghram,lo4 using a mass spectrometer, have determinedthe composition of carbon vapour in equilibrium with carbon in a Knudsencell at 2500" K.The vapour consists mainly of C(g), C,(g), and C,(g) andthe calculated heats of sublimation of these species are 171, 190, and 200kcal./mole respectively. Thus the high value of around 170 kcal./mole forthe heat of sublimation of monatomic carbon seems established. It issupported by the high D(C-0) value already discussed, by the total vapour-pressure measurements of several workers,lo5 by the mass-spectroscopicLangmuir-type experiments of Honig,lo6 and by the more recent evaporation-and effusion-rate experiments of Thorn and Wins10w.l~~ A review on thedetermination of the latent heat of carbon L(C) has been published byKern.lo8 The following values are now generally accepted: D(N,) = 9-76 ev(225.04 &- 0.1 kcal./mole); D(C0) = 11.09 ev (25576 0.43 kcal./mole);L(C) = 170.89 & 0.5 kcal./mole.The value of the effusion cell-mass spectrometer method is well illustratedby its contribution to the solution of the problem of the latent heat ofsublimation of carbon, but this is only one important example of its power.Since it was developed five years ago, the method has been applied withconspicuous success to the elucidation of the chemical composition andtemperature-pressure behaviour of many vapours at high temperatures,notably of inorganic oxides.The entire subject was reviewed some timeago by Brewer and S e a r ~ y . ~ ~ Since then the method has been applied tothe determination of the heats of sublimation of boron and boric oxide,lo9the gaseous oxides of zirconium, tungsten, and titanium,l1° and severalmetals of low volatility.111Using a saturated vapour method, Allen 112 has determined the heat ofsublimation of chromous iodide.The value (71.4 kcal./mole), when com-bined with known values for the heat of formation of CrI,(c) and the heatsof atomisation of chromium and iodine, gives a value of 55.7 kcal./molefor the Cr-I average bond energy. The heats of vaporisation of the followingsubstances have been derived from vapour-pressure studies: 2 : 3 : 3-tri-chlor~heptafluorobutane,~~~ cobalt nitrosyl carbonyl,ll* acetone,l15 andl o 2 C. R. Lagergren, Diss. Abs.. 1956, 16, 770.lo3 T.E. Brackett, J. Phys. Chem., 1956, 24, 1103.lo* W. A. Chupka and M. G. Inghram, ibid., 1955, 59, 100.Io5 M. Hoch, P. E. Blackburn, D. P. Dingledy, and H. L. Johnston, ibid., p. 97;K. J . Thorn and G. H. Winslow, J . Chew. Phys., 1955, 23, 1369; P. Goldfinger, MLm.SOC. roy. sci. Lizge, 1955, 15, 341.Io8 R. E. Honig, J. Chern. Phys., 1954, 22, 126.lo' K. J . Thorn and G. H. Winslow, ibid., 1957, 26, 1S6.lo6 D. M. Kern, J. Chem. Educ., 1956, 33, 272.lo9 A. W. Searcy and E. Myers, J. Phys. Chem., 1957, 61, 957.J. Berkowitz, W. A. Chupka, and M. C. Inghram, -1. Chem. Phys., 1967,26, 1207;1957, 27, 85; J . Phys. Chem.. 1957, 61, 1569.111 R. G. Johnston, D. E. Hudson, W. C. Caldwell, F. 11. Spedding, and M'. R.Savage, J. Chern. Phys., 1956, 25, 917.112 T.L. Allen, J. Anzer. Chern. Soc., 1956, 78, 5476.113 R. H. Capps and W. M. Jackson, J. Phys. Chew., 1956, 60, 811.114 B. Mohai and G. Bor, Naturwiss., 1957, 44, 325.115 R. A. Pennington and K. A. Dobe, J . Amel.. Chew. SOC., 1957, 79, 805NELSON DIELECTRIC MEASUREMEN?'S. 83n- and iso-propyl and wand iso-butyl nitrate ; 116 and from vapour-flow calori-metry: 1 : 1 : 2-trichloroethane, propan-1-01, and propan-2-01.117Petit et aZ.118 have measured the heats of fusion of KF, LiF, CaF,, SrF,,and BaF, by high-temperature cryometry and those of the alkali boratesand molybdates by using a thermal diagram method. Kemp et aZ.119 havereported cryoscopic heat of fusion and vaporisation data for a series ofaliphatic di- and tri-nitroxy-compounds.Waddington's group at theU.S. Bureau of Mines have reported comprehensive investigations of thethermodynamic properties of a number of compounds of key importanceto the petroleum industry.120 Among the experimental methods employedwere those of flow and low-temperature calorimetry and comparativeebulliometry. The results, in conjunction with previously or currentlydetermined heats of combustion , yield thermodynamic data, includingheats of formation of the vapours and liquids, and heats of fusion andvaporisation. The compounds studied include thiophenol, butane-l-thiol,methyl-n-propylamine, ethanethiol, dimethylamine , fluorobenzene , cyclo-heptane, cyclooctane, 1 : 3 : 5-cycZoheptatrieneJ and a series of l-olefins.Li 121 has summarised data on the heats of vaporisation and fusion of pyr-idine. Bondi and Simkin have discussed the hydrogen-bond contributionto the heats of vaporisation of aliphatic alcohols.From data in theliterature, Papini and Cuomo 123 calculated the heat of vaporisation ofethyl alcohol from 0" to 200" c. Marcus 124 has devised formulae by whichthe energies and entropies of vaporisation of liquids and metals may beestimated.H. M.DIELECTRIC MEASUREMENTS.SINCE Debye's formulation of the theory of the electrical polarisation ofmatter, by far the most important application of dielectric measurementshas been to evaluate dipole moments. Although dipole-moment studiescontinue valuable in the field of molecular structure, a rapidly growinginterest in the wider subject of dielectric relaxation is now evident and thisReport is confined to it.However, for molecular polarisabilities and dipole116 P. Gray and M. W. Pratt, J., 1957, 2163.11' K. D. Williams and R. H. Harrison, J . Chem. Phys., 1957, 26, 1049.11* G. Petit and A. Crbmieu, Compt. rend., 1956, 243, 360; G. Petit and M. Jaeger,llg M. D. Kemp, S. Goldhagen, and F. A. Zihlman, J . Phys. Chem., 1957, 61, 240.l20 D. W. Scott, J. P. McCullough, W. D. Good, J. F. Messerly, R. E. Pennington,T. C. Kincheloe, I. A. Hossenlopp, D. R. Douslin, and C,. Waddington, J . Amer. Chem.Soc., 1956, 78, 5457; D. W. Scott, J. P. McCullough, W. N. Hubbard, J. F. Messerly,I. A. Hossenlopp, F. R. Frow, and G. Waddington, ibid., p. 5463; H. L. Finke, D. W.Scott, M.E. Gross, J. F. Messerly, and G. Waddington, ibid., p. 5467; J. P. McCullough,W. N. Hubbard, F. R. Frow, I. A. Hossenlopp, and G. Waddington, ibid., 1957, 79, 561;D. W. Scott, H. L. Finke, J. P. McCullough, J. F. Messerly, R. E. Pennington, I. A.Hossenlopp, and G. Waddington, ibid., p. 1062; J. P. McCullough, H. L. Finke, M. EGross, J. F. Messerly, and G. Waddington, J . Phys. Chem., 1957, 61, 289.ibid., 1957, 244, 1734, 1900.Ie1 K. Li, J . Phys. Chem., 1957, 61, 782.14t A. Bondi and D. J. Simkin, J . Chem. Phys,, 1956, 25, 1073.las G. Papini and S. Cuomo, Antincindio, 1956, 8, 338.gZ4 R. J. Marcus, J . Chem. Phys., 1957, 26, 176584 GENERAL AND PHYSICAL CXEMISTRY.moments we mention the books by Smith and Smyth and the review bySutton which have appeared since these topics were last reported; we omitalso more specialised fields of ferro-electrics and dielectric saturation andbreakdown.The period reviewed is confined to 1955-1957, except wherea topic has not been reviewed before.General Theory of Relaxation Phenomena.-Several important reviewshave appeared. One by Bottcher emphasises the molecular interpretation.An excellent summary of dielectric absorption in solids and liquids is givenby Dryden and Meakin~.~ Smyth’s book is the most comprehensivetreatise on dielectric behaviour available.Further attempts torefine Debye’s expression 6 relating the relaxation time of a molecule to itsmolecular dimensions and the inner friction of the medium have been made.While often yielding the correct order of magnitude for the size of therelaxing molecule, the Debye equation (in which the macroscopic viscosityis commonly used in place of the inaccessible coefficient of inner friction) issometimes conspicuously inadequate , especially for spherical molecules inmedia of widely differing macroscopic viscosities.Hill divides polar liquidsinto two classes according to whether or not the rotation of the dipoles is pre-vented by freezing. For liquids which lose all orientational freedom on solidi-fication, an equation similar to Debye’s is offered to describe the variation ofrelaxation time with viscosity ( 7 ) . Debye’s “ molecular radius ” is replacedby the mean radius of gyration ( K ) of the molecule about any axis normalto the dipole axis :Relaxation time, viscosity, and molecular dimensions.Satisfactory agreement with experiment for a number of organic liquids withrigid structure is reported from the use of this equation, which includesPowles’s expression relating the macroscopic relaxation time (T*) to themicroscopic, or molecular, relaxation time (T).isthe dielectric constant at zero frequency and elco that a t high frequencies. Theprimes (’) and seconds (”) are used to denote the real and imaginary parts,respectively, of the complex dielectric constant.No simple dependence of T* on 7 is to be expected for liquids which retainorientational freedom on solidification, but Fairweather lo has suggestedthat, analogously to macroscopic turbulence, the energy loss should beV is the molar volume,1 J .W. Smith, ‘‘ Electric Dipole Moments,” Butterworths Scientific Publications,2 C. P. Smyth, “ Dielectric Behaviour and Structure,” McGraw-Hill Book Co., Inc.,L. E. Sutton, ‘ I Determination of Organic Structures by Physical Methods,” ed.C. J. F. Bottcher, Chew. WeekbEad, 1956, 52, 460.5 J. S. Drydy and R. J. Meakins, Rev. Pure Afipl. Chem. (Australia), 1957, 7, 15.P. Debye,R. S. Holland, G. N. Roberts, and C. P. Smyth, J . Amer. Chew. Soc., 1956, 78, 20. * N. E. Hill, Proc. Roy. Soc., 1957, A , 240, 101.J. G. Powles, J . Chem. Phys., 1953, 21, 633.lo A. Fairweather, Pioc. Phys. Soc., 1955, 68, B, 1038London, 1955.New York, 1955.Braude and Nachod, Academic Press Inc., New York, 1955, ch. 9.Polar Molecules,” Chemical Catalog Co., New York, 1929, ch.VNELSON DIELECTRIC iblvlEASUKEhlEN?’S. 85related to density rather than viscosity when T* is small, -q being the dominantfactor with processes of long T*. This approach was tested quantitativelyin the microwave region for dilute solutions of benzophenone in benzene andcarbon tetrachloride at different temperatures ; results in fair agreement withtheory are claimed, although the experimental results may be in errorowing to the unusual form of the tan &frequency curves. Emphasising theinadequacy of taking a sphere as a model for all molecules, and following theearlier ideas of Perrin l1 and Fischer,l2 Le F h r e and his co-workers l3 intro-duced the use of “ shape factors ”. They sought a correlation between T*of a standard molecule (nitrobenzene) in various solvents and certainproperties of the solvent. It was noticed that T* was more linearly relatedto the product of q of the solvent and some measure of the anisotropy of thesolvent, than to y1 itself. Two empirical equations were developed whichpermit an a priori calculation of T* from the polarisability ellipsoids of thesolute molecules and the viscosities, depolarisation factors, and dielectricconstants of the solvents.The absence of a close correspondence between T* and y1 for both solutionsand pure liquids is sometimes attributable to special effects, such as non-rigidity or molecular association.For example, intermolecular hydrogen-bonding may be responsible l4 for the substantially larger T* of py-rrolidinethan of pyrrole which has the larger 3.In fact, Aihara and Davies l5 usedsuch departures to assess the degree of non-rigidity of certain molecules, acondition for detecting non-rigidity being that T* should be less than thatexpected for a rigid structure. Many substituted benzene, aniline, alicyclic,and oxalic acid derivatives were studied and qualitative estimates of rigiditymade in most cases. Similar arguments were used to account for the shortrelaxation times of solutions of diphenyl ether and certain cychhexanederivatives.16 A more detailed high-frequency study in decalin solution ofthree hydroxy-compounds in which the hydroxyl groups are protected bybulky radicals, thus hindering formation of hydrogen-bonds, shows theexistence of two distinct absorption regions.1’ The lower-frequency absorp-tion was attributed to rotation of the molecule as a whole and the higher oneto independent rotation of the hydroxyl group about the carbon-oxygenbond.Both processes have similar activation energies (2.8-3-1 kcal./mole),the larger frequency factor of the latter giving rise to the higher frequencyof absorption. Dipole-moment components along the axes and at rightangles to the axes of the molecules, calculated from bond moments, agreedwell with values calculated from the experimental data by use of Onsager’sequation, thus supporting the interpretation of the absorptions. The rigidmolecule, o-dichlorobenzene, in contrast, showed a single relaxation time,though Poleyls has suggested that a second dispersion for such moleculesl1 F.Perrin, J . Phys. Radium, 1934, 5, 497.l2 E. Fischer, 2. Physik, 1949, 12’9, 49.l 3 J. Y. H. Chau, R. J. W. Le Fkvre, and J. Tardif, J . , 1967, 2293.l4 R. S. Holland, Diss. Abs., 1966, 16, 34.l5 A. Aihara and M. Davies, J . Colloid Sci., 1356, 11, 671.l6 F. Dieringer, 2. Physik, 1956, 145, 184.l7 M. Davies and R. J. Meakins, J . Chem. Phys., 1957, 26, 1584.18 J. P. Poley, AppL Sci. Res., 1955, 4(5), 33786 GENERAL AND PHYSICAL CHEMISTRY.may exist at even higher frequencies, because of the discrepancy betweenemf and n2. Indeed, a small rise in d f at f > 1O1O c./sec. was observed forlarge molecules such as nitrobenzene. A molecular resonance mechanismhas been suggested for this absorption.lgDistribution of relaxation times.A useful summary and critical dis-cussion 2o of the various ways of analysing and representing dielectric datahas been given. The equations of Fuoss and Kirkwood 21 and of Cole andCole 22 for symmetrical and that of Davidson and Cole 23 for unsymmetricaldispersions having a distribution of relaxation times are the most satisfactory.Poley's 24 suggestion that the asymmetry of dispersion observed for poly-hydroxy-compounds 23 arises from a superposition of several relaxationeffects fails to make the data fit. Other examples of viscous polar liquidswhere Davidson and Cole's skewed-arc representation applies best have beenThat the asymmetry cannot be due to long-range interactionthrough hydrogen bonds has been pointed out by Denny25 who observedasymmetric dispersions for alkyl halides at low temperatures.An interestingcase has been reported by Winslow et al. for solutions of tolyl xylyl sulphonein supercooled o-terphenyl, where the distribution of relaxation times de-creased with dilution.26 Clearly, dipole-dipole interaction cannot be thedominant factor here and it is thought that the condition for Debye behaviour,namely, that the period of the applied field should be large compared withthe average time between inelastic collisions, is not fulfilled. A theoreticaltreatment 27 for spherical molecules in a crystalline field shows that thepresence of barriers of different magnitude between equilibrium orientationsmay produce a discrete set of relaxation times, the maxima of dielectric lossfrequently being asymmetrical.Hydrogen-Bonded Systems.-Multiple dispersion has been found forseveral short-chain alkyl alcohols.28 The principal absorption, characterisedby a single relaxation time, is believed to involve partial breaking and re-forming of intermolecular hydrogen bonds to permit reorientation ofhydroxyl groups, while the high-frequency dispersion, described by a rangeof relaxation times, arises from orientation of the alkyl group with respectto the H-O-H plane.The latter process, being less specifically co-operative,is the faster. Smyth and his co-workers 29 prefer these mechanisms to theearlier views of Brot et aZ.30 that the dispersions are due to quasi-crystallinecomplexes and free molecules, respectively.Values of E,' in excess of n2l9 J. P. Poley, J . Chem. Phys., 1955, 23. 405.2O R. H. Cole, ibid., p. 493.21 R. M. Fuossand J . G. Kirkwood, J . Amer. Chenz. Soc., 1941, 63, 385.22 K. S . Cole and R. H. Cole, J . Chem. Phys., 1941, 9, 341.2s D. W. Davidson and R. H. Cole, ibid., 1961, 19, 1484.24 J. P. Poley, Physicu, 1953, 19, 300.25 D. J. Denny, J . Chem. Phys.. 1957, 27, 259.26 J. W. Winslow, R. J. Good, and P. E. Berghausen, ibid., p. 309.2 7 J. D. Hoffman and B. Axilrod, J . Res. Nut. Bur. Stand., 1955, 54, 357; J. a.Hoffman, J . Chem. Phys., 1955, 23, 1331.28 F. X. Hassion and R. H. Cole, ibid., p. 1756; W. Dannhauser and K. H. ('ole,ibid., p. 1762; D. J. Denny and R. H.Cole, ibid., I>. 1767.z 9 G. B. Rathmann, A. J. Curtis, P. L. McGeer, and C. Y. Smyth, J . Anier. Ckem.Soc., 1956, 78, 2035.30 C. Brot, M. Magat, and L. Reinisch, Kolloid Z., 1953, 134, 101NELSON : DIELECTRIC; MEASUREMENTS. 87suggest a third dispersion a t higher frequencies; this has been observed byBrot31 Empirical values of Kirkwood’s 32 correlation factor g were cal-culated and their temperature-dependences analysed in terms of associationequilibria of the type (ROH),* (ROH),+,.28 The onset of local struc-ture, leading ultimately to glass formation, appears to be responsible for thecurvature of the plot of log T* against 1/T plots a t low temperatures. As-sociation in poly(ethy1ene glycols) 33 and in solutions of o-cresol and eugenol 34has been studied at microwave frequencies, and intramolecular hydrogen-bonding identified as the origin of the radio-frequency absorption in certainsubstituted o-phen~ls.~~Recent work36 on the dielectricrelaxation process in ice supports B jerrum’s lattice-defect mechanism.37Imperfections of two types were assumed : (i) orientational defects producedby the rotation of a water molecule around one of its four bonds in thehexagonal lattice, and (ii) ionised states where a proton moves to a neighbour-ing molecule forming H30+ and OH- ions.For both cases the possibleproton jumps were treated statistically and the theory was extended tomixed hydrogen fluoride-ice crystals. The results showed that the protontransfer at H30+ ions is the dominant mechanism at the lower concentrationsof hydrogen fluoride and for high concentrations the orientational-defectprocess is the more important.36 Riehl 38 has assessed the activation energyfor ion-pair formation (8-9 kcal./mole) and for orientation (12-13 kcal./mole). On the basis of the greatly reduced relaxation times and lowactivation energies (ca.4 kcal./mole) for solid solutions of ammoniumfluoride in ice, Zaromb and Brill 39 have suggested that ions might generatefault sites which are propagated over large distances in the lattice; it wascalculated that the rotation of as many as 2-5 x lo4 water molecules isaffected by 0.002% of ammonium fluoride.*ORecent measurements indicate that the dispersion for pure water is moreconsistent with a narrow spectrum of relaxation times than a singleIt is surprising that the Debye equation should be so well obeyed for water,a system where marked deviations might be expected.Grant,42 however,has shown that a similar equation can be derived by starting from the morerealistic model of the structure of the liquid due to Haggis et aZ.43 Whilethis model adequately explains the decrease in relaxation time observed fordilute ionic solutions in terms of an increasing number of broken hydrogenIce, water, and aqueous ionic solutions.31 C . Brot, Arch. sci. (Geneva), 1956, 9, Spec. No., 49.32 J. G. Kirkwood, J . Chem. Phys., 1939, 7, 175.33 N. Koizumi and T. Hanai, J . Phys. Cherut., 1956, 60, 1496; N. Koizumj, J . Client.34 E. Fischer and N. Zengin, Z.Physik, 1957, 147, 113.35 R. J. Meakins, Trans. Faraday Soc., 1955, 51, 371.36 H. Granicher, C. Jaccard, P. Scherrer, and A. Steinemann, Discuss. I;araday Soc.,1967, 23, 50; Helv. Phys. Acta, 1955, 28, 300.37 N. Bjerrum, Kgl. danske Videnskab. Selskab, Mat-fys. Medd., 1951, 27, No. 1.38 N. Riehl, Zhur. $2. Khim., 1955, 29, 1372.39 S. Zaromb and R. Brill, J . Chpm. Phys., 1956, 24, 896.* O S. Zaromb, ibid., p. 1110.r1 E. H. Grant, T. J. Buchanan, and H. F. Cook, ibid., 1957, 26, 156.dl E. H. Grant, ibid., p. 1575.43 G. H. Haggis, J. B. Hasted, and T. J. Buchanan, ibid., 1952, 20, 1452.Phys., 1957, 27, 62588 GENERAL AND PHYSICA4L CHEMISTRY.bonds, it fails to account for effects at high concentrations where the trendis reversed. These observations were interpreted in terms of hydration ofions by Harris and O’Konski and discussed in relation to various types ofion-solven t interaction .uPhase Transitions and Orientation Freedom in Solids.-Smyth has col-lected and summarised most of the available data up to 1953, and gives over100 references.The review by Dryden and Meakins also is fairly com-prehensive. Molecular shape has been correlated with orientational freedomin solid phases for tetrahalogenomethanes 45 where the condition for freedomof rotation is that the van der Waals radii along the carbon-halogen axesshould differ by no more than 9%. For molecules of more irregular shape,rotation of segments or groups within the molecule may be the cause ofabsorption, as observed for certain solid triglycerides,46 camphor deriv-atives:’ and liydroxy-compounds.4s The parallelism between relaxationtime, activation energy, and frequency factor on the one hand, and chain-length on the other, has confirmed that the low-frequency absorption inlong-chain aliphatic esters and ethers arises from a rotation of the moleculeas a whole about the long axis.49 The need for the presence of lattice im-perfections has been suggested.49, 50 No explanation of the microwavedispersion in these compounds has yet been established, though Harper andO’Dwyer’s model,51 based on free rotation of the dipoles, is consistent withthe data for long-chain methyl esters.52 Cole and his collaborators havestudied the changes in dielectric behaviour accompanying the order-disordertransitions in solid hydrogen and deuterium halides 53 and hydrogen sul-phide.54 The experimental results were discussed in relation to possiblestructures of the various phases; dipole interactions alone do not adequatelyaccount for the observed results and the need for an extension of the measure-ments to higher frequencies (>1 Mc./sec.) has been stressed.The low-temperature phases showed multiple dispersion, suggesting that anisotropymay be important, as in solid methanol and CH,0D.55 The staticdielectric constants for the high-temperature phases in both the halides andthe sulphide were in reasonable agreement with values calculated from gasdipole moments by Onsager’s equation, thus indicating the absence ofsignificant co-operative effects from orientation.Phase transitions insodium ~almitate,~G thiocy~lohexane,~~ long-chain t h i ~ l s , ~ * and mixtures of44 F. E. Harris and C. T. O’Konski, J . Phys. Chem., 1957, 61, 310.45 R. C. Millar and C. P. Smyth, J . Anwr. Chenz. Soc., 1957, 79, 20.46 A. Di Giacomo and C. P. Smyth, ibid., 1956, 78, 2027.* 7 M. Freymann, J . Phys. Radium, 1956, 17, 326.* 8 R. J. Meakins, Trans. Furaday Soc., 1956, 52, 320.4g J. S. Dryden and S. Dasgupta, ibid., 1955, 51, 1661; J. W. Arnold and R. J.6 O J. S. Dryden, J . Chem. Phys., 1957, 26, 604.61 P. G. Harper and J. J. O’Dwyer, Proc. Phys. SOC., 1955, 68, A , 1184.62 J. S. Dryden and H. K. Welsh, Austra2. J. Sci. Res., 1951, 4, 616.53 R. H. Cole and S. Havriliak, Discuss. Faraday SOC., 1957, 23, 31; J .Chem. Phys.,54 S. Havriliak, R. W. Swenson, and R. H. Cole, ibid., p. 134.55 D. W. Davidson, Canad. J . Chem., 1957, 35, 458.6 6 H. E. Wirth and W. W. Wellman, J . Phys. Chew, 1956, 60, 919.5 7 L. Reinisch, Compt. rend., 1956, 242, 2915.58 A. Di Giacomo and C. P. Smyth, J . Amer. Chem. Soc., 1966, 78, 2032.Meakins, ibid., p. 1667.1955, 23, 2455NELSON DIELECTRIC MEASUREMENTS. 89dichloro-nitro-o-xylenes 59 have been studied by dielectric methods. Thethiols did not show the high dielectric constants and losses characteristic ofthe corresponding alcohols.Polymers.-Several reviews and books have 63* 62 Powles 63has correlated the dielectric, mechanical, and nuclear magnetic absorptionsof polyisobutene, poly(methy1 methacrylate), and poly(methy1 cc-chloro-acrylate) .The close relation between dielectric and mechanical relaxationprocesses, not always obvious from a comparison of the respective spectra,can often be shown when the data are treated by the method of reducedvariables described by Ferry et aZ.a In this treatment an empirical function( bT) was suggested to describe the temperature dependences of both electricaland mechanical relaxation processes in a remarkably wide range of systems;the universality of the function arises because the rates of all the processesdepend on temperature principally through their common dependence onfree volume. Activation energies evaluated from bT for poly(methy1acrylate) and several vinyl polymers were strongly temperature-dependentand larger than those found by Offergeld from conventional (linear) rateplots.65 Increase in chain-length of the side-groups in the acetals of poly-(vinyl alcohol) 66 increased the most probable relaxation time while theintroduction of bulky groups may prevent rotation completely, as doesbenzoylation of the hydroxyl groups in cellulose and ~tarch.6~ Carbonylgroups in polyethylene, which seem always to be present, can cause lossesover a wide range of frequencies and Mikhailov et aZ.68 have shown a directproportionality between the magnitude of the loss and the number of suchgroups present. Low- and high-frequency absorptions were attributed tothe movement of carbonyl groups in crystalline and amorphous regions,respectively, although both dispersion regions in polychlorotrifluoroethyleneare associated with processes in the amorphous zones.69 The effect ofplasticisers on the dielectric properties of poly(viny1 chloride), 70 poly(viny1-idene chloride),71 and amylose and amylopectin triacetates 72 has been in-vestigated. While the presence of plasticiser usually facilitates rotation ofpolar groups through the formation of a more open structure, decreasing the6D R. E. Wood and C. Boyars, J . Phys. Chem., 1956, 60, 1584.6o H. Stager, “ Werkstoff lrunde der Electrotechnischen Isolierstoffe,” Gebruder61 D. W. McCall, “ The Technology and Uses of Ethylene Polymers,” ed. Renfrew62 R. H. Norman, Proc. Inst. Rubber Ind., 1957, 4, 47.63 J. G. Powles, Arch sci. (Geneva), 1956, 9, Spec. No., 182.64 J. D. Ferry, M. L. Williams, and E. R. Fitzgerald, J . Phys. Chem., 1955, 59,403; M. L. Williams, R. F. Landel, and J. D. Ferry, J . Amer. Chem. Soc., 1955,77, 3701.66 G. Offergeld, Nature, 1956, 178, 1460.66 I. M. Erlikl and P. H. Shcherbak, Zhur. tekh. Fix., 1955, 25, 1575.67 P. Abadie, R. Charbonni&re, A. Gidel, P. Girard, and A. Guilbot, Compt. rend.,1955, 240, 1772; 1955, 241, 1137; see also C. W. Lewis and D. H. Hogle, J . PolymerSci., 1956, 21, 411.68 G. P. Mikhailov. S. P. Kabin, and B. I. Sazhin, Zhur. fekh. Fiz., 1955, 25, 590;G. P. Mikhailov, A. M. Lobanov, and B. I. Sazhin, ibid., 1954, 24, 1553.69 G. P. Mikhailov and B. I. Sazhin, ibid., 1956, 26, 1723.‘O P. Caillon and E. Groubert, Conzpt. rend., 1956, 242, 1313.71 B. L. Funt and T. H. Sutherland, Canad. J . Chem., 1955, 33,1669.7a C. F. Ferraro, J. J. Maurer, and W. T. Zager, J . Polymer Sci., 1956, 21, 427.Borntraeger, Berlin, 1955.and Morgan, Iliffe and Sons, London, 1957, ch. 890 GENERAL 4 N D PHYSICAL CHEMISTRY.activation energy and increasing the frequency of maximum absorption (fc) ,the opposite trend has been observed for amylose and amylopectin acetatesplasticised with, e.g., dimethyl phthalate, the branched-chain polymer showinga second dispersion at high freq~encies.~~ The loss in the unplasticisedsystems was attributed to co-operative motion of segments of neighbouringmolecules, and in the plasticised polymers to rotation of acetate groups. Itwas also suggested that the negative entropy value for the high-frequency dis-persion might be due to a decrease in the number of configurations availableto a branch-chain or segment before orientation. Plasticiser efficiency hasbeen related to the polarity of the plasticiser molecule 73 and to the enthalpyof acti~ation.~lThe Kirkwood-Fuoss theory of dielectric dispersion in polymer solutions,modified to include hydrodynamic interactions 74 between chain-segments,has been applied to van Beek’s data 75 for poly(viny1 acetate) in toluene atradio-frequences. 76 Theoretical and experimental values of the maximumreduced dispersion and activation energies agreed well, but the inversedependence offc on 2/M (where M is the molecular weight) required by theorywas not observed. van Beek and Hermans 77 have recently formulatedalternative equations based on a model in which each polymer molecule canbe subdivided into N sub-molecules whose ends carry electrical charges.Two dispersion regions were predicted, one at low frequencies (fccc 1/N2) andone at high frequencies (fc independent of N ) , neither region being dependenton M. Solutions of cellulose acetate in dioxan were studied and in this casefc depends on the degree of polymerisati~n.~~ The low-frequency loss (inexcess of that caused by D.C. conduction) observed for metal carboxylategels in non-polar solvents has been attributed to the hindered movement ofmicellar ions.79 Application of the Wagner-Sillars theory to the data forlead stearate in liquid paraffin suggests that the average shape of theparticles is that of a long prolate spheroid.81Adsorbed Molecules.-Both apparent polarisation and energy loss in avariety of systems under different conditions of surface coverage, tem-perature, and frequency have been measured. Plots of the electrical capacityof a condenser containing the solid-adsorbate system against volume of gasadsorbed usually show two almost linear sections. 82-86 With adsorbed ethylchloride, sulphur dioxide, and ammonia on non-porous rutile, studied by73 C. F. Ferraro and J. J. Maurer, J . Phys. Chem., 1956, 60, 382.74 W. G. Hammerle and J. G. Kirkwood, J . Chem. Phys., 1955, 23, 1743.75 L. K. H. van Beek, Thesis, Leiden, 1955.7 6 W. G. Hammerle and J. G. Kirkwood, J . Chem. Phys., 1956, 24, 1277.7 7 L. K. H. van Beek and J. J. Hermans, J . Polymer Sci., 1957, 23, 211; I.. deHrouchPre and L. K. H. van Beek, Rec. Trav. chim., 1956, 75, 355.78 P. C. Scherer, D. W. Levi, and M. C. Hawkins, J . Polymer Sci., 1957, 24, 19.70 S. M. Nelson, A. Gilmour, and R. C . Pink, J . , 1956, 3463.* O R. W. Sillars, J . Inst. Elect. Eng., 1937, 80, 378.81 J. Nesbitt and R. C. Pink, Paper presented a t Second International Congress ofSurface Activity, 1957.8a R. McIntosh, E. K. Rideal, and J. A. Snelgrove, Proc. Roy. SOL, 1951, A ,208, 292.83 L. N. Kurbatov, Zhur. $2. Khim., 1954, 28, 287.8p I. V. Zhilenkov, ibid., 1966, 30, 2519.86 G. Khodadadi, Compt. rend., 1957, 244, 198.88 M. Shimizu, J. Chem. Soc. Japan, 1964, 75, 885; 1955, 76, 1030, 1126NELSON DIELECTRIC MEASUREMENTS. 91McIntosh and his co-worker~,~~ the change in slope corresponded to the com-pletion of a unimolecular layer. The apparent polarisation at the higherlevels of adsorption approximated to that of the bulk liquid, whereas thatfor the incompletely covered surface was lower. In contrast, the apparentpolarisation of polar molecules adsorbed on silica gel decreased with increas-ing volume of gas a d s ~ r b e d . ~ ~ - ~ ~ $ ~ ~ The position of this discontinuity wasnot related to the area occupied by the adsorbed molecule, but rather to thenumber of adsorption centress8 This behaviour is believed to be charac-teristic of porous ad~orbents.8~ For butane and ethyl chloride on silica gel,two types of film, differing in density, were suggested, while for waterrotational freedom in the first adsorbed layer may be limited to two di-mensions. 82 Although various evaluations of the dielectric constant of theadsorbed species have been attempted,s8s 9O no entirely satisfactory formula isyet available. At least two dispersion regions have been observed for thesilica gel-water system.91392 Rolland and Bernard 91 attributed these to" free " and " bound " water, a Debye-type mechanism being implied.However, there is substantial evidence for a Maxwell-Wagner origin for theaudiofrequency loss. Heukelom and van Reijen 93 showed that the low-frequency dielectric constant was independent of the nature and quantity ofthe substance adsorbed. Kamiyoshi and Odaki g4 also favour an ionicmechanism, on the evidence of an increase of the heights with risingtemperature. In agreement with this view Zhilenkov 84 observed a move-ment of to higher frequencies on increasing the electrolyte con-centration in the gel. A change with time, from an " amorphous " to amore ordered structure, has been suggested for adsorbed water on variousglasses 95 and ionic crystals.g6 Both dipolar and ionic mechanisms havebeen suggested for certain clay mineral-water systems,97 the former seemingthe more probable; the positions of the loss maxima (lo2-lo7 c./sec.)indicate that the adsorbed water exists in a much more highly ordered statethan in liquid water and, under certain conditions, than in ice. The increasein fc with increase in adsorbate concentration was attributed to a disorderingeffect on the first adsorbed layer by molecules in the second layer. Themultiple adsorption sometimes observed may be due to water films ondifferent layer surfaces. Dipolar relaxation was also shown by adsorbedwater on c e l l u l ~ s e . ~ ~ ~ ~ ~ Muus 98 has ascribed the low-frequency loss (at lowwater contents) to the displacement of protons in hydrogen-bonds between87 M. H. Waldman, J. A. Snelgrove, and R. McIntosh, Canad. J . Chem., 1953,8 8 J. A. Snelgrove, H. Greenspan, and R. McIntosh, ibid., 1953, 31, 72; E. TIT.8g S. E. Petrie and R. McIntosh, ibid., 1957, 35, 183.g1 M. T. Rolland and R. Bernard, Compt. rent., 1951, 232, 1098.92 J. Le Bot and S. Montagner, ibid., 1951, 233, 862.93 W. Heukelom and L. L. van Reijen, J . Chinz. Phys., 1954, 51, 632.s4 I(. Kamiyoshi and T. Odake, J . Chem. Phys., 1953, 21, 1295.95 S. Kurosaki, S. Saito, and G. Sato, ibid., 1955, 23, 1846.O 6 J. Baruch and W. Low, BulE. Res. Couticil IsvaeE, 1953, 3, 31.O 7 J. Muir, Trans. Faraday Soc., 1954, 50, 249; B. J. Goldsmith, Thesis, Hull, 1950.98 L. T. Muus, Trans. Danish Acad. Tech. Sci., 1953, No. 4.9s R. Seidman and S. G. Mason, Canad. J . Chem., 1954, 32, 744.31, 998.Channen and R. McIntosh, ibid., 1955, 33, 172.G. C. Benson, E. W. Channen, and R. McIntosh, J . Colloid Sci., 1956, 11, 69392 GENERAL AND PHYSICAL CHEMISTRY.lccalised bound water molecules and hydroxyl groups of the polymer. Athigher water contents the absorption was characterised by a large activationenergy (38 kcal./mole) and was proportional to the quantity of non-localisedbound water.The Reporter thanks Mr. H. 13. Huang for his assistance.S. &I. N.F. D. S. BUTEMENT.C. KEMBALL.A. LEDWITH.H. MACKLE.S. M. NELSON.J. SHERIDAN.L. H. SUTCLIFFE.H. R. THIRSK.C. F. TIPPER

ISSN:0365-6217    

DOI:10.1039/AR9575400007

出版商:RSC    

年代:1957

数据来源: RSC

摘要:

INORGANIC CHEMISTRY.1. INTRODUCTION.THIS Report follows the pattern adopted last year. The chemistry ofelements in the main groups is discussed systematically according to thePeriodic Table in Section 2, and this is followed by a treatment of thetransition elements which deals first with some general aspects of co-ordination chemistry and then with the chemistry of the individual elementsgroup by group. We begin with a summary of some recent applications ofligand-field theory to problems in inorganic chemistry. This theory hasproved helpful in understanding the stereochemistry of complex ions, theirmagnetic and optical behaviour, and their heats of formation. It has alsobeen successful in interpreting interionic distances in simple binary com-pounds, e.g., the occurrence of several M-F distances in a fluoride such asMnF,. Several general reviews of the theory have appeared during theyear.l These include introductory accounts la) as well as more rigorousand detailed treatments.lCyd Applications to the stereochemistry andmagnetic behaviour of transition elements have also been discussed.lb, I t istherefore unnecessary to restate the theory in detail or to give a generalsurvey of the results obtained, and the present Report will be restricted tothose advances of direct interest to inorganic chemistry which have beenmade during the past year.Ligand(or crystal)-field theory deals with the influence which the electro-static field generated by surrounding groups or ligands has on the energylevels of the central ion.The effect arises because the electrons on thecentral ion tend to avoid those regions where the electrostatic field of thesurrounding ligands is largest. For example, in an isolated Ti3+ ion whichhas just one electron in a d orbital, the five d orbitals are degenerate; ie.,they have the same energy. However, if the Ti3+ ion is surrounded octa-hedrally by six fluoride ions, as in TiFG3-, the d orbitals split into two sub-sets:(i) Those orbitals (d,z, dx8--y2) which are directed mainly towards the positionsoccupied by the six surrounding ions are destabilized because electrons inthem would be repelled by the charges on the ions; they are sometimescalled d, or e, orbitals; (ii) those orbitals (dxy, d, d,) which are directedin between the positions occupied by the surrounding groups will be stabilizedbecause they represent favourable distributions in which electrons on thecentral ion can be disposed as far away from the ligands as possible; thissub-set is referred to as d, or tzq.The following paragraphs indicate howthese ideas have been applied recently to several inorganic systems.TLe crystal structure of many transition-inetal trifluorides is built up ofregular or almost regular octahedra of fluoride ions which are joined by( n ) J . S. Griffith and L. E. Orgel, Quai,f. Rev., 1957, 11, 381; (G) X i . J. Gillespieand R. S . Nyholm, ibid., p. 339; (s) W. Moffitt and C. J. Ballhausen, Ann. Rev. Phys.Chewz., 1956, 7, 107; ( d ) L. E. Orgel, Inst. Infernat. Ckiwz.Solvay, l O & h Conseil Chini.,1956, 289; R. S. Nyholm, ibid.. p 22.94 INORGANIC CHEMISTlZY.sharing corners, each octahedron having a metal ion at its centre.2 Man-ganese trifluoride, however, has a lower symmetry resulting from thepresence of three different Mn-F distances in the lattice, 1.79, 1-91, and2.09 This can be understood in terms of ligand-field theory by suppos-ing that the octahedral field of the fluoride ions splits the d orbitals of theMn3+ ion into a lower triplet (d,) and an upper doublet (a,) but that thissplitting is not very large. The four d electrons in Mn3+ will therefore beunpaired and will be distributed one in each of the three d, orbitals, pointingin between the surrounding fluoride ions, and one in the d,t orbital.Thecharge on this last electron will repel the fluoride ions on the z-axis and thisaccounts for the abnormally large interionic distance in this direction. Thetheory predicts the same effect for any octahedrally co-ordinated crystalstructure or co-ordination compound in which the central ion has four un-paired d electrons, and this has been confirmed for chromous fluoride, CrF,,in which the Cr2+ ion is isoelectronic with the Mn3+ The C r F distanceis 2.43 A along the z-axis of the octahedron but only 2.01 and 1.98 A alongthe x- andy-directions. It is clear that it is no longer possible in many casesto think of ionic radii and of spherically symmetrical ions, since the interionicdistance depends on the geometry of the occupied orbitals and the directionof approach of the surrounding groups.An extension of the arguments outlined above leads one to expect largedistortions from octahedral symmetry not only in the case of four unpairedd electrons but also (a) when there are six electrons paired off in the d,orbitals and one unpaired electron in d, (e.g., low-spin Co2+), and (b) whenthere are nine d electrons.An example of the latter case is cupric fluoridein which there are two fluoride ions at 2-27 A and four at 1.93 A.5 Otherdifluorides with 5, 6, 7, 8, or 10 d electrons have an essentially un-distorted rutile-type lattice in which the various M-F bonds differ by onlyabout 0.03 A, the z-axis of the octahedron being the shortesL6Distortions from cubic symmetry which occur in certain transition-metaloxides can be simply related to the electronic configuration of the metal ion.Large deviations are expected for d4 and d9 ions in octahedral sites as justmentioned, and also for d3, d4, d8, and d9 ions in tetrahedral sites.' Thusthe following spinels deviate from cubic symmetry at room temperature :CuFe20,, CuCr20g, NiCr20a, Mn,O,, and ZnMn,O,.It seems possible thatcrystal-field theory may also explain the observed distribution of spinelsbetween the normal and inverted structures. Of the simple monoxides, allhave rock-salt symmetry except CuO which has four oxide ions in square planararrangement around each Cu2+ ion; this is an extreme example of the pre-dicted distortion, in which the two remaining oxide ions of the octahedronhave been removed right away from the influence of the central ion.2 M.A. Hepworth, K. H. Jack, R. D. Peacock, and G. J. Westland, Acfa Crysf.,8 M. A. Hepworth and K. H. Jack, ibid., p. 345; M. A. Hepworth, I(. H. Jack,1967, 10, 63.and R. S. Nyholm, Nature, 1957, 179, 211.Orgel and J. D. Dunitz, Nature, 1957, 179, 462.6 W. H. Baur, Naturwiss., 1957, 44, 349.7 J. D. Dunitz and L. E. Orgel, J . Phys. and Chetn. Solids, 1967, 3, 30.K. H. Jack and R. Maitland, Proc. Cheat. SOL, 1957, 232.C. Billy and H. M. Haendler, J . Amer. Chem. Soc., 1957, 79, 1049; see also L. EThe magnetic behaviour of octahedral complexes of iron, ruthenium, andosmium in various oxidation states has been interpreted in terms of ligand-field theory.8 The effective paramagnetic moment is frequently less than thatexpected for the spin-only moment and is markedly temperature-dependent.This is related to the strength of the coupling between the spin and orbitalangular momenta which increases with atomic number.As the effectivemoment is inversely proportional to the spin-orbit coupling constant itfollows that, for comparable complexes, the magnetic moment will increasein the sequence 0s < RLI < Fe. Variation of magnetic moment withtemperature is reported and discussed for the complexes K,KuCl,,K ,RuCl,,H ,O, (NH,) ,RuCl,,H ,O, K ,RuCl,, and K20sC1,.2. THE MAIN GROUPS.Group 1.-A model has been suggested for dilute solutions of alkali metalsin liquid ammonia based on the concept of a neutral species comprising ametal ion solvated with ammonia molecules, the valency electron from themetal being localized on the protons of these mole~ules.~ This neutralspecies can dissociate like an ion pair and can associate to a dimer.Themodel is consistent with the paramagnetic and electrical properties of suchsolutions, with the large volume increase on mixing, and with some aspectsof the absorption spectra; it is also consistent with recent nuclear magneticresonance data on solutions of sodium in liquid ammonia and is consideredto remove some of the inconsistencies inherent in the " electron cavity "model. Solutions in alkylamines have also been studied; in particular, theconductivity of lithium in methylamine lo and the absorption spectra oflithium, sodium, and potassium in a variety of primary mono- and di-amines.11Moderately stable blue solutions of potassium or sodium-potassium alloyscan be obtained in tetrahydrofuran, ethylene glycol dimethyl ether, andother ethers, but sodium alone does not dissolve.12 The solutions are goodreducing agents and are frequently more convenient to handle than aredispersions or amalgams.Advantages over solutions in liquid ammonia arefreedom from ammonolysis and the possibility of working at room tem-perature.Potassamide forms a diammine at low temperatures, KNH2,2NH,; ithas a dissociation pressure of 52 mm. Hg at -65" and is completely dis-sociated into ammonia and potassamide at room temperature. Lithiumamide and sodamide do not appear to form analogous compounds.13 Ninehydrates of sodium hydroxide have been isolated and identified by X-raydiffraction techniques, and the complete crystal structures of the mono-,tetra-, and hepta-hydrates determined.Other hydrates contained 2&, ZP,A. Earnshaw, B. M. Figgis, J. Lewis, and R. S. Nyholm, Nafuve, 1957,179, 1121.E. Becker, R. H. Lindquist, and B. J. Alder, J . Cheqn. Phys., 1956, 25, 971; seel o E. C. Evers, A. E. Young, and A. J. Panson, J . Amer. Chem. SOC., 1967, 79,G. Hohlstein and U. Wannagat, 2. anorg. Chem., 1956, 288, 193; G. \V. A.also H. M. McConnell and C. H. Holm, ibid., 1957, 26, 1517.6118.Fowles, W. R. McGregor, and M. C. R. Symons, J., 1957, 3329.l2 J. L. Down, J. Lewis, B. Moore, and G. Wilkinson, Proc. Chem. SOC., 1967, 209.l3 R.Juza and H. Liedtke, Z. anovg. Chew., 1967, 290, 20596 INORGANIC CHEMISTRY.3&, 3*, and 5 equivalents of water, the 24-hydrate being dimorphic. Therewas no evidence for a dihydrate and it was concluded that reports of thiscompound in the literature probably referred to one of the 2&-hydrates.14A study of the molecular composition of alkali halide vapours indicatesthat, except for the cmium salts, there is a significant concentration ofdimers. For sodium fluoride, lithium chloride, and lithium bromide thereis also an observable number of trimers. For the last two salts, for example,at a total pressure of lo-, mm. Hg, there is one trimer for every six monomers,and nearly three times as many dimers as monomers. Heats of dimeriz-ation are about 45 kcal.mole-l and heats of trimerization about 35 kcal.Group 11.-Beryllium amalgam has been prepared by electrolysis of afused equimolar mixture of sodium chloride and beryllium chloride, a mercurycathode being used under an atmosphere of argon.16 The amalgam, whichis very sensitive to traces of oxygen, varies from a free-flowing liquid to athick paste depending on the concentration of beryllium, and can be used toprepare the pure element.Thermal and X-ray analysis of the system KF-BeF, has shown thepresence of the compounds K,BeF, (peritectic pt. 740"), K,BeF, (m. p. 791"),KBeF, (m. p. 406"), and KBe,F, (decomp. 275").17 Ammonium trifluoro-beryllate and ammonium trifluoromanganate(I1) react in aqueous solutionto give diammonium manganous tetrafluoroberyllate, which was identifiedby analysis and X-ray powder diagram : l8mole-1.152NH4BeF3 + NH4MnF3 - (NHJ,Mn(BeF,),,6H20 + NH,FBeryllium oxyacetate, Be,O(OAc),, m.p. 285", and beryllium oxymono-chloroacetate, Be40(CH2C1*CO2),, m. p. 230°, when fused together yieldeither Be,O(OAc) ,(CH,Cl*CO ,) or Be40 ( OAC)~( CH ,Cl*CO ,) depending onthe molar ratio used; the former compound melts incongruently at 198" andthe latter congruently at 230°.19 Beryllium oxyacetate (A) forms additioncompounds with ammonia, amines, and sulphur dioxide having the formulae :A,4NH3, A,4MeNH ,, A, 3E t N H ,, and 3A,4S 0 2.20 Beryllium oxynapht hoateshave been prepared, the product from a-naphthoic acid melting at 247" andthat from the p-acid at 336".,l Both compounds are monomeric, covalentmolecules.The use of unipositive magnesium as a reducing agent in organic chemistryhas been reviewed.22The compounds HMgX have been obtained as crystalline diether com-plexes by reduction of the corresponding Grignard compounds RMgX withP.W. Hemily, Acta Cvyst., 1957, 10, 37; J. A. Wunderlich, ibid., p. 462; P. W.Hemily and J. A. Wunderlich, ibid., p. 454.l5 R. C. Miller and P. Kusch, J . Chern. Pltys., 1956, 25, 860.lC M. C. Kells, K. B. Holden, and C. I. Whitman, J . Awzer. Chem. SOC., 1957, '79, 3925.1 7 M. P. Borzenkova, A. V. Novoselova, Yu. P. Simanov, V. I. Chernykh, and Ye. I.l8 L. R. Batsanova, A. V. Novoselova, and Yu. P. Simanov, ibid., p. 2638.lB A. V. Novoselova and K.N. Semenenko, ibid., p. 2344.2o A. I. Grigor'yev, A. V. Novoselova, and K. N. Semenenko, ibid., 1957, 2, 1374.5?1 L. Krasnec, J . Kratsmjr-SmogroviC, and A. Pivoda, Chem. Zvesti, 1957, 11, 575.22 M. D. Rausch, W. E. McEwen, and J. Kleinberg, Chenz. Rev., 1957, 57, 417.Yarembash, Zhur. neorg. Khim., 1956, 1, 2071ADDISON AND GREEN WOOD : MAIN GROUPS. 97diborane. The chloride crystallizes from tetrahydrofuran and the bromideand iodide from diethyl ether, but the bound ether cannot be removedwithout decomposition of the h ~ d r i d e . ~ ~ By contrast, the hydride bromidesand hydride iodides of calcium, strontium, and barium, like the hydridechlorides reported last year, are stable salts melting in the region 660-860';they are readily prepared by fusing the appropriate alkaline-earth metalhydride and halide together at 900°.24Group 111.-The conditions under which amorphous boron of high puritycan be produced have been extensively studied 25 and an ever-increasingnumber of papers is being published on the chemistry of this element.Details have been given of the preparation and properties of the cubic formof boron nitride.26 Up to 300 mg.have been prepared in a single experiment(typically at 1800" and 85,000 atm.), and, under special conditions, octa-hedral crystallites as large as 0-3 mm. in edge have been obtained. Thenitride, which is exceptionally hard, has the zinc-blende structure andvaries in colour from black through brown and red to yellow and whitedepending on impurities.Boron phosphide has also been prepared in thezinc-blende structure 27 and a new group of compounds in the closely relatedchalcopyrite structure has been announced, vix., ABX,, where A = Zn orCd, B = Si, Ge, or Sn, and X = P or As.28Several reviews have appeared on the structure of the boron hydridesand other electron-deficient molecules.29 The structure of the new hydrideB9HI5 is built up from the boron skeleton shown in (Ia). This is an icosa-hedral fragment formed by removing three connected boron atoms not23 E. Wiberg and P. Strevel, Annalen, 1957, 607, 9.24 P. Ehrlich and H. Gortz, 2. anorg. Chem., 1956, 288, 148; P. Ehrlich and H.26 V. I. Mikheyeva, F. I. Shamai, V. Yu. Markina, and Ye. Ya. Krylova, Zhur.28 R. H. Wentorf, J . Chem.Phys., 1957, 26, 956.27 P. Popper and T. A. Ingles, Nature, 1957, 179, 1075.28 C. H. L. Goodman, ibid., p. 828.29 H. C. Longuet-Higgins, Quart. Rev., 1957, 11, 121; W. N. Lipscomb, J . Pleys.Chem., 1957, 61, 23; R. E. Rundle, ibid., p. 45; R. E. Dickerson and W. N. Lipscomb,J. Chem. Phys., 1957, 27, 212.Kulke, ibid., p. 156.neorg. Khirn., 1957, 2, 1223, 1232, 1242, 1248.REP.-VOL. LIV 98 INORGANIC CHEMISTRY.forming an equilateral triangle. The position of the bridging hydrogenatoms is indicated in (Ib).30 When decaborane, B1,H1,, reacts with iodine,substitution occurs at the apices of the two pentagonal pyramids to giveB1,H121, (2) .31 Reaction with acetonitrile, however, is more complicatedand the structure of the product, Bl,H1,,2MeCN, has not been completelyel~cidated.~,Diborane is conveniently prepared by reaction of a mixture of hydrogen,ethylene, and boron trifluoride on aluminium: 33Diborane is also formed by the displacement reaction of boron trifiuoridewith borine-trialkylamine addition compounds, but when alkali- or alkaline-earth-metal hydrides are used instead of boron trifluoride, borohydrides areformed: 33BH3*NR3 + MH = MBH, + NR3Solutions of lithium or sodium borohydrides in di(methoxyethy1) etherabsorb a molar equivalent of borine to give a product which has beenformulated as a single-bridge compound M[H,B H BH,]-.34 In thesame solvent, sodium trimethoxyborohydride, NaBH(OMe),, disproportion-ates into (soluble) sodium borohydride and insoluble sodium tetramethoxy-borate, NaB (OMe),.The solubilities are reversed if tetrahydrofuran is thesolvent, and passage of diborane through the solution results in a quanti-tative conversion of the tetramethoxyborate into sodium borohydride, thusaffording a convenient new method for synthesizing this compound.35Potassium borohydride is more stable to oxidation and to thermal decom-position than is sodium borohydride, and both salts are more stable inhydrogen than in nitrogen at high temperature^.,^Diborane reacts with cyclopropane at 80" to give tri-Pz-propylboron asone of the main prod~cts.~' With dimethylaniline, diborane gives theaddition compound BH,,Ph-NMe,, but with aniline itself substitution occursto give dianilinoborine, (Ph*NH) 2BH.38 Tetramethyldiborane, Me,B,H,,reacts with calcium in liquid ammonia to give the new compoundCaHBMe,,NH,, which is considered to be the solvated calcium salt of theanion HBMe,,-.With excess of tetramethyldiborane the compoundCa[H,BMe,],,xNH, is formed.39The diammine of tetraborane, B,H1,,2NH,, has been prepared in SO%yield by addition of ammonia to an ethereal solution of tetraborane at-78". It is monomeric, stable in air, soluble in water with only very slowevolution of hydrogen, and reacts with sodium in liquid- ammonia to give30 M. Atoji, P. J. Wheatley, and W. N. Lipscomb, J . Chern. Plys., 1957, 27, 200.31 R. Schaeffer, J . Awe?.. Chem. SOC., 1957, 79, 2726.32 Idem, ibid., p. 1006.33 R. Koster and K. Ziegler, Angew. Chem., 1957, 69, 94; R. Koster, ibid., p.94.34 H. C. Brown, P. F. Stehle, and P. A. Tierney, J . Amer. Chem. SOC., 1957, 79,35 H. C. Brown, E. J. Mead, and P. A. Tierney, ibid., p. 5400.3 6 A. G. Ostroff and R. T. Sanderson, J . Inorg. Nuclear Chern., 1957, 4, 230.37 W. A. G. Graham and F. G. A. Stone, Chem. and Ind., 1957, 1096.3* V. I. Mikheyeva and Ye. M. Fedneva, Zhur. fieorg. Khim., 1957, 2, 604.39 G. W. Campbell, J . Amer. Chem. SOC., 1957, 79, 4023.2020ADDISON AND GREENWOOD: MAIN GROUPS. 99half a mol. of hydrogen and a significant yield of the recently describedborohydride NaB,H,.40 Pentaborane adds two mols. of trimethylamine at-78" to give a product B5H,,2NMe, which, when heated above loo", partlydissociates into the original components and partly decomposes intoBH,,NMe, and the polymer (BH),.With excess of trimethylamine thc,adduct yields BH,,2NMe3 and BH polymers incorporating some trimethyl-amine, which makes them thermoplastic. The reaction is envisaged asinvolving simply the removal of 2BH, by breaking bonds of order less thanone without any rearrangement of boron or hydrogen (3).41 On the other( 3 ) ( 4 ) ( 5 )hand, the reaction of pentaborane with diinethylaniiiie or dirnethylarnino-boron hydrides, (Me,N),BH,,, yields the compounds (hlc2N),B,H4 and(Me,N) 2B,H, which appear to represent a new class of boron-nitrogencompound.41 The reaction of alcohols and ketones with ycntaborane hasalso been studied.42 The reaction with acetone was complicated but withalcohols the products were alkyl borates and hydrogen :15ROH + B,Ho = 5B(OR), + 12H, (R = Me, E t , Bu)Alkyl fluorides absorb one mol.of boron trifluoride a t low teniperaturesto give complexes which melt in the region -95" & 15" and which alkylatealkylbenzenes in good yields. The electrical conductivity of the fused methyland ethyl complexes is only of the order of 4 x but the propyl, tert.-butyl, and cyclohexyl compounds have a conductivity of 4 x ohm-Icm.-land may be considered as tetrafluoroborates, R+BF,-.43 Boron trifluorideforms a yellow 1 : 1 : 1 complex with nitryl fluoride and trifluoromethyl-benzene, [Ph*CF3,N02]'BF4-, which decomposes without melting at - 50"to give boron trifluoride and an almost quantitative yield of m-nitrotrifluoro-methylbenzene.a The infrared spectrum of solid boron trifluoride-acetylfluoride at -40" indicates that the complex is acetyl tetrafluoroborate,Me*CO+BF4-.45 Ligands (L) such as pyridine and triethylamine can absorbtwo mols.of boron trihalide at low temperatures. The complexes could beformulated as ion pairs, [L,BX,] +BX4-, but single-bridge structures suchas L-BX, X BX, were preferred (X = H, F, C1, Br).= Pyridiniunitetrachloroborate [PyH]+BC14- (m. p. 118", decomp.) and tetrabromoboratc(m. p. 140", decomp.) have been prepared by reaction of boron trihalide onpyridine h y d r ~ h a l i d e . ~ ~ The crystal structure of BaBOF, is related to that40 G. Kodama and R. W. Parry, J . Amer. Client. SOC., 1957, 79, 100T.4l A. B. Burg, ibid., p. 2129.42 A. F. Zhigach, Y e .B. Kazakova, and 12. A. Kigel', Proc. Arcid. Sri. (U.S.S.R.),43 G. OlAh, S. Kuhn, and J. Olrih, J., 1957, 2174.44 G. OlAh, L. Noszkb, and A. PavlAth, Nature, 1957, 179, 146.46 B. P. Susz and J. Wuhrmann, Helv. Chim. ,4cfa, 1957, 40, 722.46 M. F. Lappert, Proc. Chem. SOC., 1957, 121.1956, 106, 9100 INOKGAKIC CHEMISTRY.of RbBF,, the rubidium being replaced by barium and one fluorine atom byoxygen .47Boron trifluoride forms a stable, white complex with dinitrogen trioxidewhich sublimes a t room temperature but does not melt in a sealed tube at300". The complex has only weak nitrating properties but is zstrongnitrosating and diazotizing reagent, suggesting that its structure isNO+BF,N0,-.48 Amino-alcohols add 18 mol. of boron trifluoride to givecomplexes which are readily converted by protonic solvents into hydroxy-alkylamine tetrafluoroborates. For example, 2-aminoethanol gavethe complex 3BF3,2NH,*CH2*CH2*OH which was converted into[OH*CH2*CH2-NH,] +BF,-.Similarly, diamines such as ethylenediaminereacted with boron trifluoride diether complex to give amine tetrafluoroboratesof the type [NH2*CH2*CH2*NH,]+BF4-.49 The gas-phase reaction ofdiazomethane with a 200-fold excess of boron trifluoride at low pressuresand temperatures gives a quantitative yield of fluoromethylboron difluoride,F2B-CH2F (m. p. -47", b. p. +7"), which is monomeric in the gas phase butassociated in the liquid and the solid phase.50 Trisilylamine reacts withboron trifluoride to form disilylaminoboron difluoride and silyl fluoride :N(SiH,), + BF, = (SiHJ,N*BF2 + Siti,FMethyldisilylamine and dimethylsilylamine react similarly to giveMe(SiH,) N-BF, and Me,N*BF,.The silylaminoboron difluorides eliminatea further mol. of silyl fluoride at higher temperatures to give borazolederivatives. 51Diboron tetrachloride has been shown by X-ray crystal structure analysisto have the planar configuration Cl,B=BCl, with a long B-B bond; it istherefore analogous to the isoelectronic species C2o4'- and N,O, (p. l10).52However, Raman data on liquid B&14 and infrared and electron-diffractiondata on the gas indicate a structure in which the plane of one BC1, group isat right angles to that of the other.63 This surprising effect is being in-vestigated further.Polymers of overall composition BC13,BC0 have been produced bysubjecting a low-pressure mixture of boron trichioride and carbon monoxideto a discharge of 11 kv €or 160 hours.The pale yellow product has a softeningpoint of 115" and, when dispersed in water, gives a fluid of the same con-sistency as raw egg-white. This solution gives no reaction for chloride ionand, when evaporated to dryness, leaves the unchanged polymer. Thepolymer is also soluble in ethanol but without appreciably increasing theviscosity of the solvent. Preliminary experiments suggest that boron tri-fluoride and carbon monoxide give a similar solid polymer and that theproduct obtained by using silicon tetrafluoride as the halide is a viscousliquid.544 7 D. &I. Chackraburtty, A c f a Cvyst., 1957, 10, 199.4 8 G.B. Bachman and T. Hokama, J . Anaer. CIaeni. SOC., 1c357, 79, 4370.4 9 E. L. Muetterties, 2. Naturforsch., 1957, 12b, 264, 265.6" J. Goubeau and I<. H. Rohwedder, Annalen, 1957, 604, 168.51 S. Sujishi and S. Witz, J . Amer. Chem. SOL., 1957, 79, 2447.62 &I. Atoji, P. J. Wheatky, and W. N. Lipscomb, J . Ckem. Yhys., 1967, 27, 196.53 D. E. Mann and L. Fano, ibid., 1957, 26, 1665.54 T. Wartik and R. M. Rosenberg, J . Inorg. Nuclew Chcm., 1957, 3, 388ADDISON AND GREENWOOI): MAIN GROUPS. 101Triphenylborondoes not form addition compounds directly with thioethers (sulphides), butwhen bromine complexes of thioethers, R,S,Br,, react with sodium tetra-phenylborate the addition compounds are formed by a reaction which canbe written as [R,SBr]+Br- + Na+BPh,- __t NaBr + [R2SBr]+BPh4--NaBr + PhBr + R2S,BPh,.Halogen addition compounds of tetrahydro-thiophen, pyridine, and trimethylamine react similarly. 56Thermal decomposition of trimethylboron at 400-600" and 1-6 atm.gives a variety of products from which the liquid CsHzoBa (4) has beenisolated. Solid polymers of composition (B,C,H,),, (BCH),, and (BC), arealso formed during the pyrolysis, the first by elimination of methane (5) andthe others by further c~ndensation.~~ Reaction of trimethylboron withoxygen at pressures below the explosion limit produces a 1 : 1 compoundwhich is not MeB(OMe), as has been previously suggested but is dimethyl-boryl methyl peroxide, Me,BOOMe. The peroxide rearranges in a sealedtube in the liquid or the gas phase at room temperature with first-orderkinetics to give the originally suggested isomeric compound MeB(0Me) ,.The physical and chemical properties of both compounds have been studied.58Several borazens in which the B=N bond is conjugated to an aromaticsystem have been prepared by the reaction of trimethylboron with aniline orpyrrole, or the reaction of boron trichloride with diphenylamine. Theinfrared spectra of these compounds indicate a lowering of the R-N bondorder and suggest that the free electron of the nitrogen is no longer availablefor B-N bonding.59A large number of alkylboronic anhydrides, (R*BO),, have been preparedby azeotropic dehydration of the corresponding alkylboronic acids ,R*B(OH),; the arylboronic anhydrides can be prepared by the reaction oftriarylborons with boric oxide.The reaction of these anhydrides with borontrichloride has been found to be a general method for preparing alkyl- andaryl-boron dichlorides, R*BC12.60 The corresponding difluorides are bestprepared by the action of antimony trifluoride 011 the dichlorides. The dipolemoments of these various compounds and their tendencies to isomerize ordisproportionate were also studied, as were the preparation and dis-proportionation of dialkylboron chlorides, R,BCl.GOBoron trichloride forms stable 1 : 1 addition compounds with cyclicethers if these have five- or six-membered rings, but three- and four-membered rings were cleaved to form chloroalkoxyboron esters.Additioncompounds are also formed with alkyl chloroalkyl ethers, but di(ch1oro-methyl) ether did not react.61 The interaction of ethylene glycol with boronThe organic compounds of boron have been reviewed. 5565 M. F. Lappert, Chem. Rev., 1956, 56, 959.56 H. Bohme and E. Boll, 2. anorg. Chem., 1957, 291, 160.5 7 J. Goubeau and R. Epple, Chem. Ber., 1957, 90, 171.5 8 K. C. Petry and F. H. Verhoek, J . Amer. Chem. SOL, 1966, 78, 6416.59 H. J. Becher, 2. anorg. Chew., 1957,289, 262; see also idem, ibid., 1956, 288, 235.e0 P. A. McCusker, E. C. Ashby, and H. S. Makowski, J . Atner. Chenz. SOC., 1957,79, 5179, 5182; P. A. McCusker and H. S. hlakowski, ibid., p. 6185; C. Curran, P. A.McCusker, and H. S. Rlakowski, ibid., p. 5188; G.F. Hennion, P. A. McCusker, E. C.Ashby, and A. J. Rutkowski, ibid., p. 5190; P. A. McCusker, G. I;. Hennion, and E. C .Ashby, ibid., p. 5192; G. F. Hennion, P. A. McCusker, E. C. Ashby, and A. J. Rutkow-ski, ibid., p. 5194.81 J. 1). Edwards, Gerrard, and M. F. Lappert, J., 1957, 348, 377102 INORGANIC CHEMISTRY.trichloride or alkoxyboron chlorides has been used to prepare cyclic boroncompounds of general formula (CH,O),BX where X is C1, OH, OR, OPh,O*CH,*CH,*OH, O*CH,*CH,*O*B (O-CH,) ,, or O*CH2-CH,*O*B (OR) 2.62Phenylboron dichloride does not react with ethers at room temperature, butat higher temperatures C-0 fission occurs [except with diphenyl ether anddi(chloroethy1)etherl to give an alkyl chloride and Ph*BCl*OR. Studies withoptically active ethers indicate that fission is preceded by carbonium-ionformation.63Recent developments in organometallic syntheses have been reviewedwith particular emphasis on stcreospecific catalysts based on organo-aluminium compounds. 64 Triethylaluminium reacts slowly with a sus-pension of dicyclopentadienyltitanium dichloride in It-heptane to give a bluesolution which, on being cooled to -50", gives a good yield of a compoundformulated as (C5H5),TiC1,-A1Et2, m. p. 126". The complex is a weakcatalyst for the polymerization of ethylene.65 An alternative structure hasbeen suggested which involves tervalent titanium, (C,H,),TiCl,Et,AlCI,because of the known paramagnetism of the closely related comples(C,H5) ,TiCl,Etl~AlCll~, m. p. 80°, formed under similar conditions.66A kinetic study of the exchange of chloride between aluminium trichlorideand liquid carbonyl chloride has been interpreted in terms of a weak donor-acceptor interaction between the two compounds.Hydrogen chloridereduces the rate of exchange, possibly by means of the reactionAlCl, -k HC1+ COCl, + H*COCl,+ + AlC1,- despite the fact that thereis no compound formation between aluminium chloride and hydrogenchloride in the absence of a proton acceptor (in this case the very weakacceptor carbonyl ~hloride).~' The 1 : 1 addition compound betweenaluminium trichloride and acetyl chloride has been shown by infraredspectroscopy to be predominantly in the ionic form Me*CO+AlCl,-, and asimilar structure was found for the new complex with mesitoyl chloride :Me,C,H2-CO+AlC14-.68 A reinvestigation of the system aluminium tri-chloride-phosphorus oxychloride has demonstrated the existence of twocongruent compounds, AlCl,,POCl,, m.p. 186-5", and A1C1,,2POC13, m. p.165", as well as a solvate, A1Cl,,GPOCl3, which separates on long standingfrom solutions rich in the ox;ychloride.69 The complex HA1C1,OH,2Et2O isconsidered to be formed (analogously to HA1C1,,2Et2O) when a saturatedsolution of water in ether reacts with the stoicheiometric amount of an-hydrous aluminium trichloride. 70The crystal structure of gallium &chloride confirms that it is Ga+GaCl,-Each univalent Ga' ion has eight nearest ncighbours, all chlorine atoms fromsurrounding tetrahedral GaC1,- groups, arranged at the corners of a dodeca-82 J. A.Blau, W. Gerrard, and M. F. Lappert, J . , 1967, 308, 4116.63 S. H. Dandegaonker, W. Gerrard, and M. F. Lappert, ibid., p. 2893.8q K. Ziegler, Angew. Chew., 1956, 68, 721; Suomen Kern., 1957, 30, 109.85 G. Natta, P. Pino, G. Mazzanti, and U. Giannini, J . -4mer. Chpn?. Sor., 1957,6 8 D. S. Breslow and h-. R. Newburg, ibid., p. 5072.13' J. L. Huston and C. E. Lang, J . Inorg. Nuclear Chem., 1957, 4, 30.6 8 B. P. Susz and J. J. Wuhrmann, Helv. Chinz. A d a , 1957, 40, 971.69 W. L. Groeneveld and A. P. Zuur, Rec. Trav. chim., 1967, 76, 1005.70 J. Miliotis, Compt. rend., 1957, 245, 1134.79, 2975ADDISON AND GREENWOOD: MAIN GROUPS. 103hedron as in the [Mo(CN)J4- Gallium dichloride and the relatedcompound Ga+AlCl,- form stable complexes with benzene, GaPhH+MCl,-,which are not isomorphous with the apparently similar complexes of benzenewith perchloric acid and silver perchlorate.This arises from the fact thatthe lowest acceptor orbital in Ga+ is a p orbital and not an s orbital as inH+ or Ag+, so that distortion is not necessary before interaction can occurwith the donor x orbital of benzene.72 The solubility of post-transitionmetals in their molten halides, of which the solubility of gallium in itsdibromide is a typical example, has been interpreted in terms of unstablesubhalides. The solutions are diamagnetic and the solubility, which dependson the temperature as well as on the particular metal and halide considered,varies between 0.01 and 10 moles %.73The physical properties of molten gallium trichloride have been studied,and it appears that there is a slight discontinuous increase in the activationenergy of viscous flow as the compound becomes supercooled despite thesymmetrical nature of the Ga,Cl, dimer.74 The electrical conductivity offused gallium trichloride and tribromide is of the order of 10-6 ohm-l cm.-l,but this increases markedly on solidification owing to formation of an ioniclattice.75 A similar effect is well known for aluminium trichloride and forphosphorus pentachloride but seems to be a t variance with the nuclearquadrupole spectrum of gallium tribromide which has been interpreted onthe basis of the bridged dimer structure known to be present in the fusedcompound.76Phase studies on the system gallium trichloride-phosphorus oxychlorideindicate a 1 : 1 compound melting at 118.5".The electrical conductivity,viscosity, surface tension, and other properties of the fused complex havebeen determined over a range of temperature and interpreted in terms ofthe ionic structure POC1,+GaC1,-.77 The C1 + Ga bond in the complex is12 kcal. mole-1 stronger than the sum of the two bridging C1+ Ga bonds inthe gaseous Ga2C1, dimer, and the heat of formation of the crystallinecomplex from its components at 25" is 10.2 kcal. m01e-l.~~ By contrast, theheat of interaction of gallium trichloride with phosphorus trichloride isonly 3-4 kcal. mole-l, and the 1 : 1 complex, which melts incongruently at2S0, is completely dissociated into its components in the liquid phase.Absence of electrical conductivity implies a simple covalent structure forthe solid, C1,P,GaC1,.79 An analogous but more stable addition compoundis reported between triphenylphosphine and triphenylaluminium, Ph3P,A1Ph,m.p. 300°.80Thermal analysis of the indium-iodine system indicates the presence of71 G. Garton and H. M. Powell, J . Inorg. Nuclear Chem., 1957, 4, 84.72 R. E. Rundle and J. D. Corbett, J . Amer. Chem. Soc., 1957, 79, 757.7 3 J. D. Corbett, S. von Winbush, and F. C. Albers, ibid., p. 3020.74 N. N. Greenwood and K. Wade, J . Inorg. Nuclear Chem., 1957, 3, 349.7 5 N. N. Greenwood and I. J. Worrall, ibid., p. 357.76 K. G. Barnes, S. L. Segel, P. J. Bray, and P. A. Casabella, J .Chewz. P1ys., 1957,7 7 N. N. Greenwood and K. Wade, J., 1957, 1516.7 8 N. N. Greenwood and P. G. Perkins, J . Inorg. Nuclear Chern., 1957, 4, 291.7 9 N. N. Greenwood, P. G. Perkins, and K. Wade, J., 1957, 4345.8 0 0. Nennhoeffer and W. Weigel, J . prnkt. Chenz., 1957, 4, 201.26, 1345; see also S. L. Segel and R. G. Barnes, ibid., 1956, 25, 578104 INORGANIC CHEMISTRY.three congruently melting compounds, In1 (365"), InI, (225"), and Id,(207") ; these m. p.s are considerably above those recorded in the literature.81Indium halides are reduced by lithium hydride in ether at -30" to givethe solid triether complex of lithium indium hydride, LiInH,,SEt 20, whichdecomposes above 0" into lithium hydride and polymeric indium hydride(InH3),. The reduction proceeds via the intermediates LiInX,H (X = C1,Br); these were isolated as liquid ether complexes and found to react bothas LiX,InX,H and as LiH,InX,.82 Reduction of indium trichloride withlithium indium hydride affords dimeric indium trihydride, In2H6, whichpolymerizes slowly at -30" and rapidly at room temperature to the in-soluble (InH3)x; when this is warmed in vacuo white polymeric indiummonohydride (InH), is formed with evolution of hydrogen, and decompositioninto metallic indium occurs above 340".82 Indium borohydride has beenprepared by reduction of trimethylindium with diborane in tetrahydrofuranat -45", but the compound decomposes above -10" and is therefore only alittle more stable than indium aluminium hydride.82 Very similar resultsare reported for the hydrogen compounds of thallium except that the reduc-tion of thallium trichloride with lithium borohydride at -110" leads tosubstitution of only two chlorine atoms, the resulting complex, TlCl(BH,) 2,decomposing above - 95" into thallous chloride, hydrogen, and diborane.83Thallous hydroxide reacts with cyclopentadiene in aqueous solutions togive a quantitative precipitate of cycZopentadienylthallium(I), C,H,Tl; thereaction is specific for thallium and detects one part in 30,000 of this ion.84Thallous sulphide, T12S, when oxidised by dry air at 250" and 100-200 mm.pressure, forms a mixture of T1,O and TI,S,03 which interact to give thecompound T1,S02.This compound is converted into thallous sulphate onprolonged oxidation and is considered to be the addition compoundTl2S,2TI2SO3.85Group 1V.-Most lamellar compounds of graphite are ionic; a possibleexception was the system with aluminium trichloride, but it has now beenfound that intercalation will not occur unless a third substance (e.g., chlorine)capable of forming negative ions is present, SO that these compounds arealso ionic.86 Sorption of bromine on graphite diminished the diamagnetismof the host to 6% of its original value. The bromine could not be completelyremoved by pumping at low pressures and the diamagnetism did not returnto its original value, about 0.1 g. of bromine being retained per g. of theswollen graphite.87 Further chemical studies on graphitic oxide are re-ported and it is concluded that five groups are present in the structure:(i) ether-bound oxygen, (ii) C=C double bonds, (iii) tertiary hydroxyl groups,81 E.A. Pereti, J . Amer. Chem. SOC., 1956, 78, 5745.* a E. Wiberg and M. Schmidt, 2. Natwforsch., 1957, lab, 54; E. Wiberg, 0. Ditt-mann, H. Noth, and M. Schmidt, ibid., p. 56; E. Wiberg, 0. Dittmann, and M. Schmidt,ibid., p. 57; E. Wiberg and H. Noth, ibid., p. 59.83 E. Wiberg, 0. Dittmann, and M. Schmidt, ;bid., p. 60; E. Wiberg, 0. Dittmann,H. Noth, and M. Schmidt, ibid., pp. 61, 62; E. Wiberg and H. Noth, ibid., p. 63.84 13. Meister, Angew. Chem., 1957, 69, 533.8 5 B. Reuter and H. TV. Levi, Z. anovg. Chem.. 1957, 291, 239, 254.8 6 M. L. Dzurus and G. R. Hennig, J . Amer. Chem. Soc., 1957, 79, 1051.87 L. 13. Reyerson, J.E. Wertz, W. Weltner, and A. Whitehurst, J . Phys. Chem.,1957, 61, 1334ADDISON AND GREENWOOD: MAIN GROUPS. 105(iv) enol groups, and (v) keto-groups.88 Carbon monofluoride (CF), is colour-less and non-conducting, suggesting that there is a direct C-F bond involvingthe fourth carbon valency in the graphite structure; this is confirmed by theinfrared spectrum which contains only one band, namely, at the frequencyof the C-F valency vibration in fluorocarb~ns.~~The preparation, properties, and chemical reactions of carbonyl sulphidehave been reviewed.g0 The infrared spectra of (dimeric) thiocarbonylchloride and its hydrolysis product confirm the structures (6) and (7).g1The " dimer " and " trimer '' of carbonyl chloride itself, however, do nothave analogous cyclic structures despite their ready dissociation into carbonylchloride ; they are trichloromethyl chloroformate, CCl,*O*COCl, and bis-trichloromethyl carbonate, CCl,*O*CO*O*CCl,, in agreement with theirformation by exhaustive chlorination of methyl formate and methylcarbonate re~pectively.~~The hydrolysis of the trithiocarbonate ion CS,2- has been elucidated bystudying its reactions with OH-, H+, Ag+, T1+, Pb2+, and Ph-NH, by use ofchemical, potentiometric, and spectroscopic methods.The process involvesaddition of OH- to a C=S double bond followed by proton rearrangement,and comprehensive reaction schemes have been evolved. Detailed in-structions for the preparation of anhydrous sodium trithiocarbonate and itshydrates are included, as well as instructions for the preparation of sodiumalkyl xanthates by the new reaction :Na,CS, + ROH = S:C(OR)*SNa + NaSH (R = Me, E t , Pr, CH,.CH,*OH)Many other reactions and equilibria were studied and the original papershould be consulted for details.93Benzoyl chloride has been used as the basis for an ionising solvent systemand numerous reactions have been studied potentiometrically and conducto-metrically. The solvent is a useful medium for preparing anhydrouschlorides and oxychlorides as well as complexes such as (Et,N)2TiC16 and(Et,N) ,ZrC16.94 Trifluoroacetic acid has also been investigated as a solventfor ionic-type reactions.Reactions with hydrogen sulphlde closely parallelthose in aqueous acids, but fewer chlorides, perchlorates, and hydrogensulphates are soluble in this solvent.Redox reactions were also investigated,88 A. Clauss, R. Plass, H. P. Boehm, and U. Hofmann, 2. anorg. Chew., lU:?i, 291,89 W. Rudorff and K. Brodersen, 2. Naturforsch., 1957, 12b, 595.91 J. Idris Jones, W. Kynaston, and J. L. Hales, J., 1957, 614.92 J. L. Hales, J. Idris Jones, and W. Kynaston, ibid., p. 618.93 G. Ingram and B. A. Toms, ibid., p. 4328.94 V. Gutmann and H. Tannenberger, Monatsh., 1957, 88, 216, 292; V. Gutmann205.R. J . Ferm, Cheun. Rev., 1957, 57, 621.and G. Schober, ibid., p. 404I o6 INORGANIC CHEMISTRY.and there was a slow reaction between the solvent itself and potassiumpermanganate to give the gases CO,, COF,, and CF,*COF, the permanganatebeing reduced to manganese(111).95 Cryoscopy indicates that, contrary toearlier ideas, acetyl trifluoroacetate reacts almost completely with excess ofacetic acid to give acetic anhydride and trifluoroacetic acid: 96Salts of the triplienylmethyl cation Ph3C+ with complex iluoro- andchloro-anions (e.g., BF,-, Tap,-, SbC1,-, SnC1,-) have been prepared byionic reactions between triphenylmethyl chloride and the appropriate silversalts in organic solvents. Infrared evidence for the configuration of thecation is considered to favour the propellor-like D, configuration rather thanthe planar D3h.97 The compounds Ph,CCl, Ph,SiCl, Ph,GeCl, and Ph,SnCldo not dissociate into triphenylmetalloid cations and chloride anions indimethylformamide if water is rigorously excluded.Other organometallichalides of Group IV and other non-aqueous solvents were studied withsimilar results.98Silicon tetrachloride forms a 1 : 2 compound with pyridine; the whiteprecipitate formed when silicon tetrachloride reacts with a large excess ofpyridine is not the 1 : 4 compound SiC1,,4py as previously claimed, but amixture of silicic acid and pyridinium hydrochloride formed by hydrolysiswhen the pyridine has not been scrupulously dried. 99 Silicon tetrachloridereacts with nitrogen in a glow discharge to give tristrichlorosilylamine,(SiCl,),N, as one of the products. Condensation by elimination of SiCl,from this compound also occurs to give two series of compounds, (i)crystalline, cyclic compounds (Si,NCl,). of which (8) is a typical member,C I- S i -IC IMe CI\ /CH2-S I - C H ~N I I ,Sic13C IH 1C - S i-CH2-Si- CH,CI/ \Me C I'SIC13 I tCHz-Si-CHzand (ii) oily chain polymers of which the first member is Si,N,Cl,, (9), thelimiting composition at high molecular weights being the same as for thecyclic series.100 Pyrolysis of trimethylchlorosilane Me,SiCl at 800" yields acrystalline product Si,C,C1,H2, to which structure (10) has been assigned onthe basis of its chemical properties and its relation to the products of pyrolysisof tetramethylsilane mentioned in last year's Report.lol Solvolysis ofsilylphosphine, SiH,*PH,, with aqueous or alcoholic alkali gave phosphine95 G.S. Fujioka and G. H. Cady, J . Amer. Chem. SOC., 1957, 79, 2451.96 E. J. Bourne, J.C. Tatlow, and R. Worrall, J., 1957, 315.9 7 D. W. A. Sharp and N. Sheppard, ibid., p. 674.9 9 U. Wannagat and F. Veilberg, 2. anorg. Chem., 1957, 291, 310.100 A. Pflugmacher and EI. Dahmen, ibid., 1957, 290, 184.101 G. Fritz. Z . Natztrforsch., 1957. 12b, 123; see also Ann. Repovts, 1956, 53, 93.A. B. Thomas and E. G. Rochow, J . Amer. Chem. SOC., 1957, 79, 1843; J. Inorg.Nuclear Chem., 1957, 4, 205ADDISON AND GREENWOOD: MAIN GROUPS. 107and one mol. of hydrogen for each Si-H bond broken, whereas acid mediasplit only the P-S bond: lo2SiH,.PH, -t 4ROH = Si(OR), + 3H, + PH, (R = H, Et)SiH,-PH, + ROH = SiH,*OR + PH,Liquid ammonia, on the other hand, gave phosphine, silane, and a range ofsolid silicon-nitrogen compounds such as (SiH,*NH),.lo2The problem of the composition and structure of silicon nitride, Si,N,,has been resolved.The compound exists in two forms which differ only inthe sequence in which planes of atoms are linked along the 001 direction ofthe crystal.lo3An inductively heated, differential thermal-analysis apparatus has beenused to show that silicon dioxide does not react with silicon to form a solidmonoxide even at the m. p. of silicon. Similarly, no evidence was found fora solid germanium monoxide.lo4The crystal structures of silicates with highly condensed anions have beenreviewed.lo5 Cation exchange between nitrosyl chloride and the zeolitesodium analcite yields nitrosyl analcite. Exchange with anhydrous sodiummetasilicate, however, indicates that nitrosyl metasilicate is unstable evenat room temperature and decomposes as follows : lo6Na,SiO, + 2NOCI + 2NaCI + (NO),SiO, __+ 2NaCI + SiO, + N,O,Germane, GeH,, can be prepared in 75% yield by reduction of an acidicaqueous solution of germanium dioxide with sodium borohydride.Lessthan 1% of digermane and only a trace of germanium are formed simul-taneously. Stannane can be prepared by the same method, but not~1urnbane.l~~Solubility measurements and anion-exchange studies indicate that anionicchloro-complexes of the type [Ge(OH),Cl,-,]- or [Ge(OH),C1,-,]2-, where xlies between 3 and 4, are the principal species present in solutions of quad-rivalent germanium in 6--9~-hydrochloric acid.lo8 No evidence was foundfor bromo-complexes in aqueous hydrobromic acid solutions.Similarexperiments with quadrivalent tin in hydrochloric acid indicated the presenceof the ions SnC1,- and SnC1,2-.108The reactions of stannic chloride with numerous alcohols have beenstudied. Primary and secondary alcohols gave either volatile additioncompounds, SnC14,2ROH, or non-volatile products, SnCl,(OR)*ROH, ormixtures of these, whereas tertiary alcohols under appropriate conditionsgave SnCl,,ROH, SnCl,(OR),ROH, or SnCl,(OR). There was no evidencefor the formation of alkyl halides, olefins, water, hydrogen chloride, orsolvolised metal chlorides which are the typical products of the reaction of102 G. Fritz and H. 0. Berkenhoff, 2. anorg. Chem., 1957, 289, 250.Io3 D. Hardie and K. H. Jack, Nature, 1957, 180, 332.104 L.Brewer and F. T. Greene, J . Phys. aizd Chem. Solids, 1957, 2, 286; I,. Brewerlo5 F. Liebau, Z.$hys. Chem. (Leipzig), 1956, 206, 73.106 I. R. Beattie, J., 1957, 367.1 0 7 T. S. Piper and M. K. Wilson, J . Inorg. Nuclear Chew., 1957, 4, 22.108 D. A. Everest and J. C. Harrison, J., 1957, 1820, 1439.and P. Zavitsanos, ibid., p. 284108 IXORGANIC CHEMISTRY.tertiary alcohols with the tetrachlorides of silicon, titanium, zirconium, andhafnium.lo9 Lithium aluminium hydride reduces triethyliodostannane,Et,SnI, to the new compound Et,SnH, b. p. 146", which is itself a strongreducing agent.l1° The vinyl ll1 and acetylene 112 compounds of tin havealso been investigated.Stannic fluoride and phosphorus pentafluoride are Friedel-Crafts catalystsand have been found to form complexes with both one and two mols.ofaldehydes, ethers, nitriles, and amines; there is also evidence of interactionwith ethyl methyl ketone, acetic acid, and ethyl acetate.l13 Stanniciodohypophosphite, Sn14,Sn(H2P02)4, has been obtained by the action ofhypophosphorous acid on a solution of stannic iodide in alcohol. It is a paleyellow solid which melts at 319" with evolution of phosphine.l14The well-known suggestion that hydrated sodium stannate,Na2Sn0,,3H20, has the structure Na,Sn(OH), has been proved correct byan analysis of the infrared spectrum of the solid.l15A new lead hydroxycarbonate, 3PbC03,2Pb(OH) 2, has been preparedfrom a solution of lead acetate and sodium hydroxide at pH 7.7 andcharacterized by its X-ray power diagram.ll6 Cryoscopic and conducto-metric studies on dilute solutions of lead acetate in sulphuric acid point tothe formation of hexa(hydrogen su1phato)plumbic acid, H2Pb(HS0,),.Itsfirst dissociation constant, 1.1 x is slightly less than that of pyro-sulphuric acid.l17Group V.-There has been considerable activity during the year on thehydrides of the Group V elements in addition to the work already reportedunder the heading of Group I on solutions in liquid ammonia and amines.A study of solid-liquid equilibria in the ternary system NH,-N2H4-NH,C1at pressures near atmospheric suggests the formation of a 1 : 1 : 1 compound,NH3,HC1,N2H4, melting incongruently at -2.5". The compoundNH4C1,3NH3 was also confirmed.l16 A lower hydride of phosphorus,PgH4, has been obtained as a yellow solid by the decomposition of P2H4at room temperature under anhydrous conditions.In the presence ofmoisture substances are formed which correspond closely to Stock's P12H,,and by heating diphosphine under appropriate conditions non-stoicheio-metric hydrides of almost any composition below PgH4 can be obtained.ugThe conflicting reports on solid hydrides of arsenic have been reviewed andseveral methods of preparing such substances have been evaluated. Anunstable, volatile hydride thought to be diarsine, As,H,, was prepared byuse of a silent electric discharge.120109 D. C. Bradley, E. V. Caldwell, and W. Wardlaw, J , 1957, 3039.110 H. H. Anderson, J . Amer. Chem. Soc., 1957, 79, 4913.111 D.Seyferth, ibid., p. 2133; S. D. Rosenberg, A. J. Gibbons, and H. E, Ramsden,ibid., p. 2137; S. D. Rosenberg and A. J. Gibbons, ibid., p. 2138.112 H. Hartmann and H. Honig, Angew. Chem., 1957, 69, 614.113 A. A. Woolf, J . Inorg. Nuclear. Chem., 1956, 3, 285.114 D. A. Everest, J., 1957, 4149.115 R. L. Williams and R. J. Pace, ibid., p. 4143.116 H. Maunch and A. Brunold, HeEu. Chim. Acta, 1957, 40, 86.1 1 7 R. J, Gillespie and E. A. Robinson, Proc. Chem. Soc., 1957, 145.118 F. R. Hurley and H. H. Sisler, J . Anaer. Clzem. SOC., 1957, 79, 2999.119 E. C. Evers and E. H. Street, ibid., 1956, 78, 5726.120 W. L. Jolly, L. B. Anderson, and R. T. Beltrami, ibid., 1957, 79, 2443ADDISON .4ND GREENWOOD: MAIN GROUPS. 109Hydrogenation of phosphorus pentachloride with lithium borohydride at-80" or lithium aluminium hydride at - 100" did not give the pentahydridebut a mixture of phosphine and hydrogen.Antimony pentachloridebehaved similarly. Hydrogenation of derivatives of quinquevalent arsenic,antimony, and bismuth of the type MR,X,, also yielded only tervalentproducts .I21 Lithium aluminium hydride and calcium aluminium hydridereduced not only tertiary aliphatic phosphine oxides and sulphides, &POand R,PS, but also triarylphosphine sulphides, Ar,PS, to trialkyl(or aryl) -phosphines, R,P, whereas with triarylphosphine oxides an aryl group waseliminated and the product was Ar2PH.122 Lithium borohydride reducesarsenic trichloride in 93% yield to arsine, and antimony trichloride in 98%yield to stibine, but with bismuth trichloride mainly decomposition productswere 0btained.1~~ Attempts to obtain the phosphorus analogue of aniline,Ph-PH,, in the same way from Ph*PCl, resulted in production of the borineaddition compounds BH3,Ph*PH2 and BH,,Ph*PClH; these, like thehomologous nitrogen compounds, readily eliminated hydrogen or hydrogenchloride, but the resulting polymers were chain compounds rather thancyclic trimers analogous to the borazoles.The arsenic and antimonyanalogues of aniline and diphenylamine were isolated as low-melting, readilyoxidizable liquids by reduction of the appropriate phenyl-substituted tri-halide, and the arsenic analogues of piperidine and pyrrolidine (in which thearsenic is in a heterocyclic ring) were likewise prepared by the reduction ofpentamethylene- and tetrarnethylene-arsenic chloride with lithium boro-hydride : 123 {CH,).AsCl _..t (CH,),AsH.Tetrapotassium hydrazinetetrasulphonate has been prepared by electro-lytic oxidation of tripotassium aminodisulphonate in aqueous solutions byusing carbon, platinum, or lead oxide anodes and fluoride ion as a catalyst : 1%2[N(S03)J3- = 2e- + [(S0,),N*N(S03),]4-A kinetic study of the hydrolysis of the nitrilotrisulphonate ion in acetate,pyridine perchlorate, or sulphite buffers (pH 5-7) shows that the reactionis of first order with respect to both nitrilotrisulphonate and hydrogen-ionconcentrations :where B is Me*CO,-, py, or SOP-.It was assumed that the velocity of thereaction was controlled by the rate of formation or decomposition of thetrisulphonated ammonium ion, [HN (S03)J2- :[N(SO3)J" + H*OH + B = [HN(SO3)JL + + BHfH S O ' + [N(S0Jsl3-= H80 + [HN(SOJJ"or [HN(so3)d2- + H,O = H&Op + [HN(SO$J"Hydrolysis is extremely rapid in unbuffered solutions.125The infrared spectrum of solid, liquid, and gaseous dinitrogen tetroxideconfirms the planar structure O,N*NO, in all three phases in agreement with121 E.Wiberg and K. 3Edi-itzer, 2. Naturfovsch., 1956, l l b , 747, 748, 750, 751,753, 755.132 F. Hein, K. Issleib, and H. Rabold, 2. anorg. CAem., 1956, 287, a 8 .123 E. Wiberg and K. Modritzer, 2. Naturforsch., 1957, 12b, 123, 135; E. Wibergand H. Noth, ibid., pp. 125, 127, 128, 131, 132.1%4 R. R. Grinstead, J . Inorg.Nuclear Chem., 1957, 4, 287.125 I;. Seel, E. Degener, and K. Kehrer, 2. anorg. Chem., 1957,2180, 103li 10 INORGANIC CHEMISTRY.X-ray diffraction, Raman, and electron-diffraction data.126 However, theinfrared spectrum of dinitrogen tetroxide dissolved in anhydrous nitric acidshows the presence of nitrosonium and nitrate ions, NO+N03-. As theconcentration of solute is increased the lines due to non-ionised N20,molecules increase in intensity. The spectrum of NO, was not observed,and magnetic measurements confirmed that the concentration of this para-magnetic species was very ~ma11.l~~ The vapour pressures of 13 systems ofdinitrogen tetroxide with organic solvents at 0" are reported and comparedwith similar data on nitrosyl chloride-organic systems.Deviations fromideality are correlated with the polar nature and donor properties of thesolvents, and used to indicate the degree of addition compound formationin each system.128The equilibrium N20, - NO + NO, has been restudied in thetemperature range 5-45', an all-glass apparatus being used, and theresults confirm and extend earlier work.129 Nitric oxide reacts withsodium amalgam to give a quantitative yield of nitrosylsodium, NaNO.Lithium, potassium, magnesium, and barium amalgams react similarly butiron, nickel, zinc, and tin amalgams form metal(@ oxides, and cadmiumamalgam does not react at all.130 When solid hyponitrites (N,0,2-) weredispersed in a potassium bromide disc for infrared experiments, the complexspectrum of the ion as observed in mulls disappeared and was replaced bya single new frequency (1445 cm.-l).It has been claimed that this indicatesthe presence of the monomeric NO- ion in solid solution though it seemssurprising that this treatment would be sufficient to rupture the N-N bondof the hyponitrite ion.131The occurrence of multiple bonding in phosphorus compounds has beenreviewed. With few exceptions phosphorus forms essentially single bondsin those compounds where its co-ordination number is 3, 5, or 6, whereascompounds with a co-ordination number of 1 or 4 almost invariably haveappreciable multiple-bond character. This can be understood in terms ofthe overlap integrals associated with the potential ~ - b o n d s . l ~ ~ The nuclearmagnetic resonance spectra of over 200 compounds of phosphorus have beenexamined and qualitatively discussed ; the technique has also proved usefulin confinning the structure of several anions of phosphorus 0xyacids.1~~The type of thermal dehydration observed with dihydrogen mono-phosphates depends on the size of the cation rather than the temperatureof dehydration.With small (Li, Be), large (K, Rb, Cs, Ag, Zn, Cd, Hg, Ca,Sr, Ba, Pb) or highly charged (Cr3+, Fe3+, Bi") cations high-molecular chainpolyphosphates are obtained, whereas with cations of intermediate size126 R. G. Snyder and I. C. Hisatsune, J . Chern. Phys., 1957, 26, 960; R. N. Wienerand E. R. Nixon, ibid., p. 906; D. W. Smith and K. Hedberg, ibid., 1956, 25, 1283.127 D. J. Millen and D. Watson, J., 1957, 1369.128 C.C. Addison and J. C. Sheldon, ibid., p. 1937.129 I. R. Beattie and S. W. Bell, ibid., p. 1681.130 H. Hohn, V. Gutmann, and 0. Sova, Monatsh., 1957, 88, 502.131 D132 J.'k. van Wazer, J . Amer. Chern. SOC., 1956, 78, 5709; H. H. Jaff6, J . Inorg.Nuclear Chew&., 1957, 4, 372.133 J. R. van Wazer, C . F. Callis, J. N. Shoolery, and R. C. Jones, J . Amer. Chewt.SOC., 1956,78, 5715; C. F. Callis, J. R. van Wazer, J. N. Shoolery, and W. A. Anderson,ibid., 1957, 79, 2719.. Millen, C. Polydoropoulos, and D. Watson, Proc. Chern. Soc., 1967, 18ADDISON AND GREENWOOD : MAIX GROUPS. 111(Na, Mg, Al, Mn2+, Fe2+, Co, Ni, Cu2+, Zn, Cd) ring nietaphosphates areformed. The structureof insoluble magnesium tetrametaphosphate was established during thecourse of this work.134 There have also been extensive investigations of(a) the thermal dehydration of phosphoric acid a t temperatures up to 870”,(b) the hydrolysis of high molecular-weight polyphosphates, and (c) theformation and properties of condensed and cross-linked p01yphosphates.l~~The reaction of alkoxytrimethylsilanes with phosphorus trichloride ortribromide results in the stepwise replacement of halogen by alkoxy-groupsand avoids the presence of hydrogen halides or tertiary bases:Me,SiOR + PX, = Me,SiX + PX,(OR), etc.136 Alkoxyphosphorus di-chlorides can be condensed at room temperature in the presence of metaloxides to give esters of polymetaphosphorous acids : 137There is some overlap between the two types.134xROPCI2 + xM,O = 2xMCI + x(RO-P”O) + [-O-P(OR)-],Molecular-weight determinations indicate that x = 4 when K --- Bu, thcstructure being that of a normal tetrametaphosphate (11).0 0R0,ll II,ROR RO/ p- 0- p,( R = M e , E t )Hypophosphoric acid is known to be symmetrical and to contain aP-P bond.The methyl and the ethyl ester of this acid, R,P20, (la), havenow been prepared by reaction of the acid with the appropriate diazoalkaneand shown to have the same structure.138 The infrared and Rarnan spectraof tetramethyldiphosphine disulphide indicate that it too has the relatedstructure Me,P(S)*P(S)Me,.139 In addition, esters of the new isomeric iso-hypophosphoric acid (13) have been shown to be capable of existence;they are prepared by the elimination of alkyl chloride from a mixture ofdialkyl chlorophosphate (phosphorochloridate) and trialkyl phosphite : l 4 O(RO)2POCI + (RO),P(O)R = RCI + R4P206 (13)The corresponding trisodium salt has been prepared by heating a mixtureof disodium hydrogen phosphate with either sodium dihydrogen phosphiteor sodium pyrophosphite : 141Na2HPOa,12H20 + NaH2P03,24H20 = Na3(HP20,) + 154H,ONa2HP04 + Na,H,P,O, = Na,(HP,06) + NaH,P03 __ ._ _ ~ -134 E. Thilo and I. Grunze, Z. mzorg. Chem., 1957, 290, 209, 223.135 (a) E. Thilo and R. Sauer, J . prakt. Chem., 1957, 4, 324; (b) J. IV. Edwardsand A. H. Herzog, J . Amer. Chem. SOC., 1957, 79, 3647; E. Thilo and W. Wicker,2. anorg. Chenz., 1957, 291, 164; (c) E. Thilo and A. Sonntag, ibid., p. 186.136 J.Fertig, W. Gerrard, and H. Herbst, J., 1957, 1488.137 R. Schwarz and H. Geulen, Chem. Ber., 1957, 90, 952.138 M. Baudler, 2. anorg. Chem., 1956, 288, 171.139 J. Goubeau, H. Reinhardt, and D. Bianchi, 2. phys. Cheni. (Fmnkfupf), 1957,140 M. Baudler and W. Giese, Z. mrovg. Cheni., 1957, 290, 268.141 H. Remy and H. Falius, Naturwiss., 1957, 44, 419.12, 387112 INORGANIC CHEMISTRY.Reaction of phosphorus trichloride with aqueous phosphoric acid gives thefree acid: PCl, + 2H,O + H,PO, = H3(HP20,) + 3HC1.1aWhen solid disodium hypophosphate (14) is heated to 230" it undergoesinternal rearrangement to form disodium pyrophosphite (15) and disodiumpyrophosphate (16). This involves breaking the P-P bonds and formingP-0-P bonds : 1420 0 0 0 0 0Na0,II II,ONa Na0,ll II O N a Na0,ll II,ONa2 P-P 3 p-o--P= f ,P-0-P,HO' ' OH H' H HO OH( 1 4 ) ( 1 5 ) (16)The disodium pyrophosphate then condenses to higher polyphosphates.Sodium pyrophosphite (15) is also formed during the pyrolytic oxidation ofdisodium hydrogen phosphite at 180", disodium hypophosphate (14) beingformed as the intermediate : 1422Na,HPO, + I, = 2Nal + Na,H,P,O, (14)An improved preparation of monoamidophosphoric (phosphoramidic)acid, H,P0,(NH2), has been given 143 and it has been shown that the com-pound readily undergoes quantitative rearrangement at 100" to givecrystalline, soluble ammonium polyme t aphospha t e ( NH,P03),.144 Improvedpreparations of diamidsphosphoric (phosphorodiamidic) acid (1 7) have alsobeen d e v i ~ e d .l ~ $ l ~ ~ The compound is slowly hydrated by moist air at roomtemperature to give ammonium hydrogen monoamidophosphate (phosphor-amidate) (18). Replacement of the five hydrogen atoms in diamidophos-phoric (phosphorodiamidic) acid by silver gives an explosive derivative.145(17) (18) (19)The reaction between pyrophosphoryl chloride and ammonia in anhyd-rous ether gives the tetramido-derivative, reaction (A), or a polymer offormula P20,N,H, which may be considered as an amide of polymeta-phosphoric acid in which one quarter of the oxygen atoms are replaced bythe isosteric NH group (19).146 In the presence of more than 0.01% ofwater the products are phosphoric triamide and diamidophosphoric(phosphorodiamidic) acid (reaction B), and with still more water (reaction C)the ammonium salt is obtained: 1460 0 0 0!I II II !IC1,P-O-PCIz + 8NH3 = 4NH4CI + (NHs)ZP-O-P(NHJz .. . (A)0 0II I I 0 0II I1CI,P-O-PCIz + 9NH3 = 4NHICI + (NH,),P-NH, + HO-P(NHJ2 . . (B)0I10 0II I IH,O + C1,P-0-PCI, + IONH, = 4NH4CI + Z(NH,),P-ONH, . . . . . (C)142 J. H. Kolitowska, Bull. Acad. polon. Sci., GI. III, 1956, 4, 783; 1957, 5, 827.143 M. Becke-Goehring and J. Sambeth, Chem. Ber., 1957, 90, 2075.144 M. Goehring and J. Sambeth, ibid., p. 232.145 R. Klement, G. Biberacher, and V. Hille, 2. anorg. Chenz., 1957, 289, 80.146 M. Goehring and K. Niedenzu, Chem. Ber., 1957, 90, 151ADDISON ,4ND GREENWOOD : MAIN GROUPS. 113Phosphorus pentachloride also undergoes complicated ammonolysis ; 14'phosphoric triamide, formed via the intermediate imido-triamide, can beisolated (reaction D) as well as the pentamide of tri-imidotriphosphoric acid(reaction E).In addition, there is a compound isomeric with phosphorictriamide which is apparently the ammonium salt of a polymeric di-imido-phosphoric (phosphorodi-imidic) acid (F) .Ha0 PCI, + 9NH3 ___t 5NH,CI + (NH2),P:NH (NH,),P:O + NH, . . (0)O H NH H O 0 NH 0I I I! II 1 1(NHJ,P-NtH + NH2tP+NH2 + HfN-P(NHJ2 __t (NH2),P-NH-P-NH-P(NHdaII , ----------;I1 . - - _ _ _ _ _ _ _ _ _,! - - - - - - - - - - - I I ! . _ _ L _ _ _ _ _ _ _ ,I I I t . (EJNH2 NH2An X-ray structure analysis of P4S3, as well as the Raman spectrum ofthe compound in the solid, liquid, and dissolved states, indicates the struc-ture (20) 148 in agreement with earlier electron-diffraction work.The penta-sulphide, P,S,, however, has the unexpected asymmetric structure (21) inwhich one P-S bond is significantly longer than the others.149The slightly volatile compound (CF3P),, which is the first known exampleof a homocyclic ring of four phosphorus atoms, has been made by threemethods: (i) reaction of CF3*P12 with mercury at room temperature,(ii) thermal decomposition of P2(CF3), a t 350" to (CF,P), and (CF,),P, and(iii) thermal decomposition of (CF,) ,PH at the same temperature to (CF,P),and CF3H. The compound melts at 65" and has an extrapolated b. p. of145". It reacts with iodine to regenerate trifluoromethylphosphorus di-iodide, and is hydrolysed by alkali to fluorofonn and other degradationproducts.150 Improved syntheses of the intermediates CF,*PI, and(CF,),PI have been published,151 and it has been found that the methodwhereby P2(CF3), is produced by shaking (CF,),PI with mercury is a goodsource of (CF3),PH if performed in the presence of a protonic acid.152A white solid of approximate composition P,O,,F1, is formed when anequimolar mixture of phosphorus trifluoride and oxygen is subjected to147 M.Becke-Goehring and K. Niedenzu, Chern. Ber., 1957, 90, 2072.148 N. Gerding, J. W. Maarsen, and P. C. Nobel, Acta Cryst., 1957, 10, 156; YuenChu Leung, J. Waser, S. van Houten, A. Vos, G. A. Wiegers, and E. H. Wiebenga,ibid., p. 574.149 S. van Houten and E. H. Wiebenga, ibid., p. 156.150 W. Mahler and A.B. Burg, J . Avner. Ghem. SOC., 1957, 79, 251.151 A. B. Burg, W. Mahler, A. J. Bilbo, C. P. Haber, and D. L. Herring, ibid.,152 A. B. Burg and W. Mahler, ibid., p. 4212.p. 247I14 IN ORGANIC CHEMISTRY.an electrical discharge at -75". At -38" this solid evolves phosphorusoxyfluoride and phosphorus pentafluoride , leaving the new polymericmaterial (PO,F),. The decomposition of P,O1,Fl, in the temperature range-25" to 0" yields the same three products and the new compound P20,F,,m. p. -0.1", b. p. 72", which behaves chemically as pyrophosphoryl fluoride,F,0P*0*POF,.153Numerous ionic reactions in phosphorus oxychloride have been studiedpotentiometrically and with visual end-point indicators.lS4 Rapid andcomplete exchange of labelled chlorine has been observed between ionicchlorides and the solvents phosphorus oxychloride, arsenic trichloride, andselenium oxychloride.Exchange is also rapid between nitrosyl chloride andits addition compounds with ferric chloride and antimony pentachloride, inagreement with their formulation as nitrosonium salts. With the morecovalent compounds carbon tetrachloride and phosphorus oxychloride,exchange with nitrosyl chloride is slow, but rapid exchange was observedwith arsenic trichloride, and phase studies showed the presence of the newcompound AsC13,2NOC1, m. p. -S5°.155Phosphorus pentachloride reacts with the trichlorides of arsenic andantimony to give white products P2C1,,,5AsC1,, m. p. 40", and P2Cl1,,4SbC1,,m. p. 111" (decomp.). Solutions of these complexes in excess of the tri-chlorides are good electrical conductors, and cryoscopy indicates that thecompounds are predominantly solvates of the ionic pentachloride,PCl,+PCl,- ,5AsCl, and PC14+PC1,-,4SbC1,, though in the former complexthere may also be a contribution from the structure 2(PC14+AsC14-),3AsC1,.156Arsenic trifluoride reacts exothermally with potassium, rubidium,cmium, and thallium fluorides to give the tetrafluoroarsenates MAsF,, butthe fluorides of lithium and sodium do not react, suggesting that stability ofthe complexes is inversely proportional to the size and polarizing power ofthe cation.157 Arsenic trifluoride does not react with chlorine under an-hydrous conditions, but in the presence of a small amount of water therecently discovered compound AsC~,~ASF,- is formed by a reaction whichis thought to involve AsF,*OH as an intermediate. The cation AsCl,+ isreadily hydrolysed but the anion AsF,- is very resistant to hydrolysis.158Similarly, arsenic trifluoride does not react with bromine or iodine in theabsence of water.However, in the presence of water hydrolytic oxidationproceeds right through to arsenic acid, H,AsO,, and compounds of the cationsAs&,+ and Ad,+ could not be is01ated.l~~ It has also been found that48% aqueous hydrofluoric acid converts potassium dihydrogen arsenate intothe hydroxyfluoroarsenate K[AsF,OH] and not the hexafluoroarsenateKAsF, as claimed in the earlier literature. The former complex, unlike thelatter, is readily hydrolysed; it can be converted into the hexafluoroarsenateby the action of anhydrous hydrofluoric acid.lG0153 U.Wannagat and J. Rademachers, 2. agzorg. Chem., 1957, 289, 66.154 V. Gutmann and F. Mairinger, ibid., p. 279.155 J. Lewis and D. B. Sowerby, J., 1957, 556, 1617.156 L. Kolditz, 2. anorg. Chem., 1957, 289, 118.157 E. L. Muetterties and W. D. Phillips, J . Amer. Chenz. Soc., 1957, 79, 3686.1 5 8 H. M. Dess, R. W. Parry, and G. L. Vidale, ibid., 1956, 78, 5730.159 H. M. Dess and R. W. Parry, ibid., p. 5735.1 6 0 I d e m , ibid., 1957, 79, 1589ADDISON AND GREENWOOD: MAIN GROUPS. 115The previously unknown acidium salts of fatty acids have been preparedas derivatives of the SbF,- anion, and numerous other oxonium, sulphonium,and hydrazinium salts of this anion have also been isolated.161 Fluorinationof antimony pentachloride with arsenic trifluoride gives tetrachloroantimonyfluoride, SbCl,+F-, m.p. 83" (decomp.) : 1623SbCI5 + AsF, = 3SbC14+F- + AsCI,The complex is a strong electrolyte in arsenic trifluoride.The chemistry of trifluoromethyl derivatives of antimony has beenextensively studied. Trifluoromethyl iodide reacts with antimony or amixture of antimony and its tri-iodide at 165" to give the compounds(CF,),Sb, (CF,) ,SbI, and (CF,)Sb12. At higher temperatures fluorocarbonsare produced. Tristrifluoromethylstibine has much weaker donor propertiesthan has trimethylstibine and can act as an electron-acceptor to form a1 : 1 compound with pyridine. The quinquevalent derivative (CF,),SbC12also forms a 1 : 1 adduct with pyridine.The preparation and reactions ofthe chloro- and bromo-derivatives were studied and they were comparedwith the corresponding compounds of phosphorus and arsenic; e.g., theiodo-trifluoromethyl compounds of antimony disproportionate more readilythan the corresponding derivatives of phosphorus and arsenic. The distibinederivative (CF,) ,Sb*Sb(CF,) , was also investigated.163Group V1.-Plastic sulphur, at least in the extended state of fibrous+sulphur, is made up of two constituents in roughly equal proportion.One is fibrous $-sulphur, formed by helices of radius 0.92 A with a period often atoms in three turns (134' A). In the needle-shaped holes of this spongystructure, small crystals of y-sulphur occur with a repeat-pattern of 9.2 A;these crystals are built up of s8 molecules.The value 3 : 2 for the ratio ofthe two periods brings about a curious epitaxis between the two constituents.After elution with carbon disulphide only the $ skeleton is left.164When sulphur, s8, is dissolved in oleum or anhydrous sulphur trioxide,the solutions vary in colour from yellow to blue and a blue solid can beisolated which has previously been assigned the formula (SO,*S),. It is nowfound that both the solid and the solutions are paramagnetic though theprecise nature of the species is not ~ 1 e a r . l ~ ~ The product obtained by passingan electric discharge through a mixture of sulphur and sulphur dioxide,which was previously thought to be a mixture of SO and S,O, in the gasphase, has been shown to be a mixture of SO, and the new compound di-sulphur monoxide, S,O; there is no evidence for sulphur monoxide.166The generally assumed structure for N,S,H,, in which there is a puckeredeight-membered ring with alternate sulphur and nitrogen atoms, has been161 F.Klages and E. Zange, Angew. Chem., 1956, 68, 704; F. Klages, E. Miihlbauer,162 L. Kolditz, 2. anorg. Chem., 1957, 289, 128.163 J. W. Dale, H. J. Emelkus, R. N. Haszeldine, and J. H. Moss, I., 1957, 3708.164 J. A. Prins, J. Schenk, and L. H. J. Wachters, Physica, 1957, 23, 746; see alsoJ. Schenk, ibid., p. 546; A. G. Pinkus, J. S. Kim, J. L. McAtee, and C. B. Concilio,J . Amer. Chem. SOC., 1957, 79, 4566.165 D. M. Gardner and G.K. Fraenkel, ibid., 1956, 78, 6411; see also D. J. E.Ingram and M. C . R. Symons, J., 1957, 2437; M. C. R. Symons, ibid., p. 2440.166 D. J. Meschi and R. J. Myers, J . Amer. Chem. SOC., 1956, 78, 6220.and W. Uhl, ibid., p. 704; F. Klages and H. Wolf, ibid., p. 705116 INORGANIC CHEMISTKY.established as correct by an X-ray crystal structure determination.167Green-yellow crystals of the new compound S,N2F2, m. p. 86", form spon-taneously when the gases SN2F, and SNF are left in contact at reducedpressure for a long lime. The compound contains no N-N or N-F bondssince it is quantitatively hydrolysed by alkali to ammonia, and this, inconjunction with its mean oxidation number of 2.6 and its monomericmolecular weight, implies the formula F*S*N*kN*S*F.168A careful reinvestigation of the system S03-H20 near the compositionH2S0, has shown that the composition of minimum conductivity (expressedin millimoles of H20 per kg. of solution " H2S04 ") varies from 2.3 at 9-66'to 1.5 a t 40.0" and is 1.9 at 25.00" at which temperature tlic minimumconductivity is 1.0432 ohm-l cm.-l and the conductivity of pure H,SO, is1.0439 ohm-l cm.-1.169 Conductivity measurements on solutions of nitro-compounds in sulphuric acid suggest that, whereas the mononitro-compoundsbehave as weak bases, di- and tri-nitro-compounds arc non-electrolytes, inagreement with earlier conclusions drawn from cryoscopy and ultravioletspectroscopy.170 Refined chemical and thermodynamic analysis has shownthat the compound known as sulphuric acid hexaliydrate is, in fact,H2S0,,6.5H20, and detailed work has thrown some light on the nature ofthe octahydrate.lnA recent determination of the crystal structure of potassiuiii pyrosulphiteconfirms earlier work that this compound contains the 02S*S0,2- ion.172This differ from the conclusions drawn from a study of the Raman spectraof aqueous solutions of pyrosuIphites, which have been interpreted in termsof the structure 02S*O*S022-.173 However, both structures should give riseto 15 Raman lines and differ only in the detailed assignment of these lines.Studies with isotopically labelled sulphur indicate that the oxidation ofsulphite by persulphate to give dithionate proceeds via the pyrosulphateion : 174SOs2- + 0,S*0.0*S0,2- = SO,2- + OsS*0.S0,2-SO,z- + OsS*0*SO,*- = SO,2- + 0,S*S0,2-An extensive study of some oxyacids of sulphur has been published.175Thivsulphuric acid has been prepared by direct addition of hydrogen sulphideto sulphur trioxide in ether at -78" and has been isolated at low temperaturesas the diether complex, H2S20,,2Et20.By use of the sulphanes, H,S,, thisreaction affords a new class of suIphuric acid, H2S,03 ( x = 92 + 1 = 2-6).With the exception of the first member, thiosulphuric acid, which is dibasic,167 E. W. Lund and S. R. Svendsen, Acta Chcm. Scand., 1057, 11, 940.168 0. Glemser and E. It'yszomirski, Angew. Chew., 1957, 69, 534.169 R. J. Gillespie, J . V. Oubridge, and C. Solomons, J., 1057, 1804.1 7 0 H. J . Gillespie and C. Solomons, ibid., p.1796; see also R. J. Gillespie and171 $:. W. Hornung, T. E. Brackett, and IV. I:. Giauque, J. Acmv. Client. Soc., 1056,172 I. Lindqvist and M. Mortsell, Acla Cryst., 1967;10, 406.173 A. Simon, K. Waldmann, and E. Steger, Z. anorg. Chem., 1958, 288, 131.174 A. W. H. Aten, K. P. Louwrier, P. Coppens, H. A. Kok, A. hI. de lioos, E.Kriek, A. Hillege, L. Vollbracht, and F. Hartog, J . Iaorg. Nuclear Chem., 1956, 3, 296.176 M. Schmidt, 2. anorg. Chem., 1957, 289, 141, 158, 175, 193.E. A. Robinson, ibid., p. 4233.78, 5747ADDISON AND GREENWOOD: MAIN GROUPS. 117these acids are strong monobasic acids and form monoether complexes;their structure is thus H(O,S*S,*H). Addition of sulphur trioxide to theseacids gives anhydrous polythionic acids, H2S,+106, which were isolated as thediether complexes. The polythionic acids are also formed by oxidation withiodine :2H,S,03 + I , = H,S,O, + 2H1In this way the previously unknown acids H2S,06, H2S1,06, and H2S1206have been prepared.Their properties indicate that the stability of thepolythionic acids is a maximum at hexathionic acid.175A method for preparing kilogram amounts of crude sulphanes, H2S,(x = 4-6) by addition of hydrogen chloride to Na,S, has been described.176The oils so obtained can be cracked and fractionated to give pure sulphanes(x = 2-5), and the higher homologues ( x = 6-8) have been prepared in apure state by the reaction 2H,S2 + S,C1, = 2HC1 + H,S,,,. In thepresence of excess of chlorosulphanes the reaction leads to higher chloro-sulphanes: 2S,C1, + H,S, = 2HC1+ S,.,,,Cl,. The physical properties andRaman spectra of all these compounds are re~0rted.l~'A convenient means of separating and purifying sulphur tetrafluoridefrom other volatile substances has been described which involves formingthe addition compound SF,,BF, and then heating this with selenium tetra-fluoride which releases the sulphur tetrafluoride quantitatively.The com-plex can also be prepared directly by fluorinating a mixture of boron andsulphur at -75". The pentafluorides of arsenic and antimony likewise form1 : 1 complexes with sulphur tetrafl~0ride.l~~ The stability of Auoro-sulphates, MSO,F, depends on the lattice energy of the fluorides from whichthey are formed and is greatest for large cations of small charge.Thermaldecomposition of thallous and silver fluorosulphates gives pyrosulphurylfluoride, S,O,F,, which is itself decomposed at higher temperatures intosulphuryl fluoride and sulphur trioxide and is hydrolysed to fluorosulphuricacid.179 Peroxydisulphuryl difluoride, S206F2, m. p. - 55.4", b. p. 67.1 O ,has been prepared by the high-temperature reaction between sulphur tri-oxide and fluoride and has been shown by chemical reactions and infraredand nuclear magnetic resonance spectroscopy to have the structureO:S(:O)F~O~O~S(:O)F:0.180 Exchange studies with radioactive sulphurindicate that thionyl chloride and thionyl bromide can dissociate ionicallyboth as pure liquids and when dissolved in sulphur dioxide.lslThe kinetics of the reaction of the selenosulphate ion with selenious acidhave been interpreted on the basis of the overall equation lS2.4SeSOZ2- + H2Se03 + 4H+ = Se,S,0,2- + Se3S2Os2- + 3H20--1 7 6 F.Fehkr and W. Laue, ibid., 1956, 288, 103.177 F. FehQ, W. Laue, and G. Winkhaus, ibid., pp. 113, 123; 1957, 290, 52; F.Fehtr and R. Berthold, ibid., p. 251; F. Feher, K. Naused, and H. Weber, ibid., p. 303.178 N. Bartlett and P. L. Robinson, Proc. Chew. SOG., 1957, 230.1 7 9 E. Hayek, A. Czaloun, and B. Krismer, Monatsh., 1956, 87, 741; E. Hayek180 F. B. Dudley and G. H. Cady, J . Amer. Chern. Soc., 1957, 79, 513.182 I. V. Yanitskii and V. I. Zelionkaite, Zhur. neoi'g. Khim., 1957, 2, 1349; seeand A. Czaloun, ibid., p. 790.L. F. Johnson and T. H. Norris, ibid., p.1584.aIso 0. M. Baram and M. P. Soldatov, ibid., p. 1289118 I N ORGANIC CHEMISTRY.The preparation of the urea and the diazine salts of pentahalogeno-tellurous acid, HTeX,, in which the stability of TeX,- increases in the se-quence C1 < Br < I, has been described. The preparation and propertiesof the 1 : 1 addition compounds of tellurium tetrabromide with S,N,,S,N,H,, and dioxan were also investigated.l= The compound TeF,,ZCsFhas been prepared by heating caesium fluoride with an excess of telluriumhexafluoride at 250" and then cooling the mixture to room temperatureduring 24 hours. The fluorides of rubidium and potassium reacted onlyincompletely under these conditions, and those of sodium, lithium, andbarium not at all.lS4 Tellurium hexafluoride also forms 1 : 2 additioncompounds with tertiary amines but does not react with amides, nitriles, orethers.185The chemistry of polonium has been exhaustively reviewed and it appearsthat knowledge of the chemistry of this element is now comparable with thatof its lighter (and less metallic) congener tellurium.lS6 The a+ phasetransition in polonium, which occurs just above room temperature, is subjectto a hysteresis of some 36" according to recent X-ray crystallographicinvestigation.ls6" More ion-exchange and solvent extraction studies onpolonium compounds have been reported.ls7 The dependence of thesolubility of polonium hydroxide on hydroxide-ion concentration shows thatthe compound is but feebly acidic.The results have been interpreted interms of the equilibrium PoO(OH), + 2KOH K2Po03 + 2H20, forwhich the equilibrium constant K, = [K,PoO,]/[KOH]~ = (8.2 & 0.4) x 10-5.The compound is thus much less acidic than tellurous acid.188 Poloniummonosulphide has been prepared on the milligram scale by precipitation withhydrogen sulphide from hydrochloric acid solutions of polonium(1v) oxy-chloride or polonium tetrachloride.Its solubility product a t room tem-perature is about 5.5 x and its decomposition in vacuo has been usedas the basis of a new method for preparing polonium metal.189Group VI1.-General aspects of the inorganic chemistry of fluorine havebeen reviewed.lgO There has been an extensive study of hydrogen fluorideas a solvent system. Of the three common binary, protonated, self-ionizingsolvents (ammonia, water, and hydrogen fluoride) the first two are knownto dissolve ranges of compounds which can act as acids and bases, but inhydrogen fluoride only " bases " were known, i.e., compounds which in-creased the fluoride-ion concentration.The study of a wide range of binaryfluorides reveals only four compounds which are capable of increasing theconcentration of the hydrofluoronium ion H2F+ and are thus able to act as" acids "; these are boron trifluoride, stannic fluoride, and the pentafluorides183 E. E. Aynsley and W. A. Campbell, J., 1957, 832.184 E. L. Muetterties, J . Amer. Chem. Soc., 1957, 79, 1004.18s E. L. Muetterties and W. D. Phillips, ibid., p. 2975.186 K. W. Bagnall, Quart.Rev., 1957, 11, 30; " Chemistry of the Rare Radioele-18*@ J. M. Goode, J . Chem. Phys., 1957, 26, 1269.187 J. Danon and A. A. L. Zamith, J . Phys. Chem., 1957, 61, 431; T. Isimori andA. Tateda, J . Chem. SOC. Japan, 1957, 78, 78; K. W. Bagnall and D. S. Robertson,J., 1957, 509.1*8 K. W. Bagnalland J. H. Freeman, ibid., p. 2161.189 K. W. Bagnall and D. S. Robertson, ibid., p. 1044.190 A. G. Sharpe, Quart. Rev., 1957, 11, 49.ments," Butterworths, 1957, pp. 3-94AIIDISON .AND GREENWOOD: MAIN GROUPS. 119of arsenic and antimony. The acidic nature of these solutes is due to theirability to act as fluoride-ion acceptors, e.g.,2HF + BF, z+= H,F+ + BF4-Such solutions can dissolve electropositive metals. A large variety ofinorganic reactions have been carried out in anhydrous hydrogen fluorideto illustrate amphoteric behaviour, solvolysis, complex formation, etc., andto prepare compounds such as BaHF3.1g1Perchloryl fluoride, which was first prepared in 1952, is now beingproduced in ton quantities, and several papers have appeared on its physicalproperties lg2 and heat of formation.lg3 The compound is a stable gas, inertand non-corrosive at room temperature, but a powerful oxidizer at highertemperatures, and its importance is due to its possible use in metal cuttingand welding and in propulsion. It is non-toxic and has the highest dielectricstrength of any known gas. Conditions have been defined for the preparationof pure perchloryl fluoride lg4 and the kinetics of its thermal decomposition,which is unimolecular and homogeneous in quartz, have been studied in thetemperature range 470-500" .lTrifluoromethyl hypofluorite, CF,*OF, decomposes reversibly a t hightemperatures into carbonyl fluoride and fluorine.In the range 250-300"the carbonyl fluoride so formed reacts with unchanged hypofluorite to giveyerfluorodimethyl peroxide, CF,*O*O*CF3, and this compound could also beobtained by the catalytic reaction of fluorine or carbonyl fluoride with carbonmonoxide or dioxide.lg6When hydrogen chloride is bubbled through a concentrated aqueoussolution of czesium chloride the compound CsC1,HCl is precipitated and itis suggested that this contains the hydrogen-bonded ion HC1,- analogous tothe HF2- ion. The other alkali-metal chlorides do not react in this wayand it appears that a large cation is necessary for ~tability.1~7Phase studies and conductivity measurements give no evidence of acompound between chlorine trifluoride and hydrogen fluoride.198 Themicrowave spectrum of gaseous bromine trifluoride establishes that themolecule is planar and has a slightly distorted T-shape just as inchJorine t r i f l u ~ r i d e .~ ~ ~ This result agrees completely with the structurededuced from an X-ray investigation on the solid at -1125°.200 Bromine191 A. F. Clifford, H. C. Beachell, and W. M. Jack, J . Inorg. Nuclear Chem., 1957,5, 57; A. F. Clifford and A. G. Morris, ibid., p. 71; A. F. Clifford and S. Kongpricha,ibid., p. 76; A. F. Clifford and J. Sargent, J . Amer. Chem.Soc., 1957, 79, 4041; seealso F. See1 and H. Sauer, Angew. Chem., 1957, 69, 135.192 R. L. Jarry, J . Phys. Chem., 1957, 61, 498; J. Simkin and R. L. Jarry, ibid.,p. 503; A. A. Maryott and S. J. Kryder, J . Chem. Phys., 1957, 27, 1121.193 C. A. Neugebauer and J. L. Margrave, J . Amer Chem. Soc., 1957, 79, 1338;see also V. H. Dibeler, R. M. Reese, and D. E. Mann, J . Chem. Phys., 1957, 27, 176.194 J. E. Sicre and H. J. Schumacher, Angew. Chem., 1957, 69, 266; see also AH^.Reports, 1956, 53, 103.195 R. Gatti, J. E. Sicre, and H. J. Schumacher, Angew. Chem., 1957, 69, 638.196 R. S. Porter and G. H. Csdy, J . Amer. Chem. SOC., 1957, 79, 5628.lg7 R. West, ibid., p. 4568.19s M. T. Rodgers, J. L. Speirs, and M. B. Panish, J . Phys. Chem., 1957, 61, 366;see also R.M. McGill, W. S. Wendolkowski, and E. J. Barber, ibid., p. 1101.199 D. W. Magnuson, J . Chern. Phys., 1957, 27, 223.200 R. D. Burbank and F. N. Bensey, ibid., p. 982120 INORGANIC CHEMISTRY.pentafluoride has likewise been shown to have a tetragonal-pyramidal-shapedmolecule with the bromine atom below the base of the pyramid, but thestructure determination of iodine pentafluoride was not completed becauseof the low symmetry and experimental difficulties.200 The crystal-structuredetermination of iodine heptafluoride at low temperatures also proveddifficult and it appears that the structure is considerably disordered owing torandom orientation of the molecules; however, it is believed that the resultsindicate a molecular geometry in which five of the fluoride atoms form atetragonal pyramid about the iodine atom which is below the base of thepyramid as in the pentafluoride, the other two fluorine atoms being situatedbelow the iodine atom.201 This is in sharp contrast to the pentagonalbipyramid suggested on the basis of Raman and infrared spectra.The equilibrium constants for the gas-phase reaction ErF, + Br2+3BrF have been determined both manometrically and by absorption spectrain the temperature range 55-107" and lead to the values -AG298 = 1.2 kcal.mole-1, -AH = 11.9 kcal.mole-1.202 The electrical conductivity of thesystem BrF,-Br, in the liquid phase has been reinvestigated and the resultsagree with earlier work. The systems BrF,-BrF, and HF-BrF, were alsoinvestigated; the conductivity of the former system varied smoothly withconcentration, whereas that of the latter was in general greater than that ofeither pure component and was maximum near 70 moles yo of HF.Theconductivity of pure bromine trifluoride at 25" is 8-01 x 10-3 and that ofthe pentafluoride 9 x ohm-lThe X-ray data on the compound KBrF,, which was remarked upon inlast year's Report, have now been reinterpreted and it has been shown that astructure with planar rather than tetrahedral BrF4- fits the data equallywell and gives more acceptable geometry and bond distances.204The formation of polyhalide complexes by reaction of interhalogencompounds with aluminium halides in acetonitrile has been studied spectro-photometrically and electr~lytically.~~~ Conductance experiments onsolutions of tetra-alkylammonium polyiodides in acetonitrile indicate thatthe ion I,- is relatively stable at concentrations greater than O ~ O ~ M , but thatbelow this concentration its dissociation into I, and I,- is virtually complete.The I,- ion in turn is unstable below 0.0002M.206 It therefore appears thatthe I,- ion can exist in solution despite the crystal-structure determinationof Et,NI, mentioned in last year's Report which showed that compoundto be Et4NI,,212.The parent acid of the tri-iodides, HI,, has been identifiedby its absorption spectrum in carbon tetrachloride solution at 25". Theequilibrium constant for the reaction HI + I,+HI, is about 100,implying a fair degree of stability for the complex.207201 R.D. Burbank and F. N. Bensey, J . Chena., Phys., 1957, 27, 981.202 R. K. Steunenberg, R. C. Vogel, and J. Fischer, J . Amer. Chem. SOC., 1957,205 L. A. Quarterman, H. H. Hyman, and J. J- Katz, J . Phys. Chem., 1957,61, 912.204 W. G. Sly and R. E. Marsh, Acta Cryst., 1957, 10, 378; S. Siegel, ibid., p. 380;205 A. I. Popov and F. B. Stute, J . Amer. Chena. SOC., 1956, 78, 5737.206 A. I. Popov, R. Y. Rygg, and N. E. Skelly, ibid., p. 5740; see also Awn. Reports,207 J. A. Magnuson and J. H. Wolfenden, J . Phys. Chenz., 1956, 60, 1665.79, 1320.see also Ann. Reports, 1956, 53, 104.1956, 53, 104ADDISON AND GREENWOOD: MAIN GROUPS. 121Complexes of iodine, iodine monochloride, and iodine monobromide withpyridine, 2-picoline, and 2 : 6-lutidine have also been studied spectro-photometrically in carbon tetrachloride, and dissociation constants obtained.The order of stability is ICI > IBr > I, as expected, but the sequencepicoline > pyridine > lutidine suggests the intervention of a steric effectwith lutidine.The complexes, many of which were previously unknown,have been isolated and characterized by m. p.208Iodine dissolves in concentrated oleums to give blue solutions which arecharacterized by an intense band at 650 mp. This band has been tentativelyassigned to the (forbidden) triplet-singlet transition of the I+ ion. Para-magnetic-susceptibility measurements on the blue solutions have beeninterpreted by postulating that the iodine is present partly as free I+, whichshould have two unpaired electrons, and partly combined as IHSO,,IHS207, or IS0,+.209Solvent-distribution studies have established that the oxidation ofastatine with fairly concentrated hydrochloric acid results in a chloro-complex, the ether-extractability of which has been used for the isolationof astatine from bismuth targets.The complex is probably AtC1,- but maypossibly be AtCl,-. Acidic solutions, which presumably contain theastatine as HAtO, react with phenol to give astatophenol analogous toiodophenol.2103. THE TRANSITION ELEMENTS.The treatment of the chemistry of the transition elements follows thepattern of the 1956 Report. Much of the published work deals with thechemistry of complexes. Those aspects which concern the structure orgeneral properties of particular types of complex are discussed first under theheading " complexes." This section involves discussion of (a) generalaspects, including properties of ligands and the " trans "-effect, (b) metalcarbonyls and their derivatives, (c) olefin and acetylene complexes, and (d)aromatic-type complexes. The chemistry of the transition elements is thendiscussed systematically in the ten transition groups.Although this divisionis necessarily somewhat arbitrary, the complexes referred to in these latersections are regarded as being more directly concerned with the chemistryof the particular elements.An excellent review (126 pages) has been published on the use of isotopictracers in the elucidation of mechanism and structure in inorganicchemistry.211 The review is comprehensive, ard covers compounds of themain-group elements as well as transition elements.Reviews have alsobeen published on " non-stoicheiometric compounds and intermetallicphases," 212 I' interstitial compounds of transition metals " (particularlythe hydrides, nitrides, and carbides) ,213 and " non-stoicheiometric ionic208 A. I. Popov and R. H. Rygg, J . Amev. Chem. SOC., 1957, 79, 4622; see also20B M. C . R. Symons, J., 1957, 387, 2186.%lo H. M. Neumann, J . Inorg. Nuclear Chem., 1957, 4, 349.211 D. R. Stranks and R. G. Willrins, Chcm. Rev., 1957, 57, 743.212 R. Collongues, Inst. Internat. Chim. Solvay, 10th Conseil Chim., 1956, 151.m J. Bknard, ibid., p. 83.0. Hassel, Proc.Chem. Soc., 1957, 250122 INORGANIC CHEMISTRY.compounds ’’ (which is concerned with recent work on binary chalkogenidesof the transition elements) .214Complexes.-(a) General. The rate of exchange of the NH, moleculebetween solvent liquid ammonia and the 15N-labelled ammines [Ag(NH,) 2J+,[Cu(NH3)J2+, and [Ni(NH3),I2+ is rapid; in contrast, slow exchange occurswith [cr(NH3),l3+ and [CO(NH,),]~+, which is consistent with their classi-fication as inner-orbital complexes.215 The importance of traces of impurityin exchange studies has been emphasized by the observation that tris-1 : 10-phenanthroline- and tris-2 : 2’-dipyridyl-cobalt (111) ions are inert to exchangewith the free ligands in acid solution, but undergo exchange in neutralsolution owing to catalysis by cobalt(I1) impurity.From exchange ex-periments with 63Ni, it has been possible to measure rate constants fordissociation of [Ni(phen) 2]2+ and [Ni(phen)12+ for comparison with knowndata on the [Ni(phen),12+ species. The rates of dissociation of nickel(r1)and copper(I1) complexes of carbon-substituted ethylenediamines,H,N-CRR’CR”R”’*NH,, decrease as alkyl substitution increases216 Therates of dissociation of tris-1 : 10-phenanthroline-iron(z1) and -iron(m), andthe racemization of the latter, depend upon the nature and concentration ofadded anions and cations. The behaviour of the iron(II1) complex isattributed to ion-pair formation with added ions (as shown by ultravioletspectra), but with the iron(I1) complex it is an ionic background effect 0nly.217By using water as solvent, the oxygen isotope fractionation (l80/160)occurring in the aquation of [Co(NH,),XI2+ (X = C1, Br, I) ions under theinfluence of the ions Hg2+, Ag+, and TP’ has been determined.These ionsincrease the rate of halide replacement, but not the rate at which isotopicequilibrium is reached. When Hg2+ is used, there is evidence for a commonintermediate from the different halogeno-cations.218 Redox potentials forthe system L2PtC1,-L2PtC12 have been measured in mixed aqueous solvent.When L = PPrn,, the cis-isomer system has higher potential than the frans-analogue. The work provides evidence for the influence of dative x-bondingon the total transfer of charge in co-ordinate bonds; the lower-valent stateof the metal is stabilized both by inductive withholding and by mesomericwithdrawal of electrons from the metal by the ligar~d.~lgA detailed account of the tram-effect in 4- and 6-co-ordinate platinumcomplexes has been presented, with many examples of the directing effectof ligands.220 The stability of the products of the reaction[Pt(CO)X212 + 2L __t 2[P (C0)LXJ(where X = C1, Br, I) depends upon the trans-effect of the ligands L intro-duced. Weakly x-bonding ligands (e.g., NH,, 9-toluidine) do not expelcarbon monoxide, but more strongly bonding ligands (pyridine or PCl,) do214 J.BCnard, Inst. Internat. Chim. Solvay, 10th Conseil Chim., 1956, 109.215 H. IJ. D. Wiesendanger, W. H. Jones, and C. S. Garner, J . Chem. Phys., 1957,27, 668.216 K.G. Wilkins and M. J. G. Williams, J., 1957, 1763, 4514; P. Ellis, R. G.Wilkins, and M. J. G. Williams, ibid., p. 4456; R. G. Wilkins, ibid., p. 4521.217 J. E. Dickens, F. Basolo, and H. M. Neumann, J . Amer. Chem. SOC., 1957,79,1286.218 F. A. Posey and H. Taube, ibid., p. 255.219 S. Ahrland and J. Chatt, J., 1957, 1379.220 I. T. Chernyayev, Zhzsr. iaeorg. Khim., 1957, 2, 475ADDISON AND GREENWOOD: THE TRANSlTION ELRMEiXTS 123so readily.221 This directing effect also operates in solutions of cupricchloride with cupric bromide in acetone, where the formation of the complexion [CuCl3Br]2- has been examined.222 The trans-eff ect influences reactionrates ; the rates of substitution of chlorine by pyridine, ammonia, glycine,aniline, thiourea, ally1 alcohol, water, and the ions OH-, NO,-, C2042-, and36Cl- in 4-co-ordinate platinum(r1) chloroammines varies with the nature ofthe entering group. An attractive dissociation mechanism for substitutionreactions in these square complexes is ~uggested.~~3 Substitution rates havealso been measured for a series of trans-compounds [Co(AA) ,Cl,]+ (whereAA = substituted ethylenediamine) and for cis-[Co(en) 2C12]+ in methanol,where reaction of the methoxide ion becomes significant.224 From an X-raystudy of seven 4-co-ordinate platinum complexes of the type K [PtAX,](where A = C1, Br, NH,, or C2H,, and X = C1 or Br) an interesting " trans "-influence in crystals is observed.The Pt-C1 or Pt-Br distance dependsupon the ligand in the trans-position, and it is claimed that under theseconditions the nitro-group has a weaker trans-influence than chlorine orbromine.225Infrared spectra for a number of nitrato-complexes of metals have beenexamined in the region 4000-700 cm.-l, and it is now possible to distinguishthe NO,- ion from a co-ordinated nitrate group. Strong absorption bandsin the regions 1530-1480 and 1290-1250 cm.-l indicate that the nitrategroup is bonded to the metal through a single oxygen atom. Absorptiondue to -0-NO, stretching occurs as a strong peak in nitrato-complexeswithin the region 1034-970 cm.-1.226 The degenerate and symmetricaldeformation vibrations of the co-ordinate NH, group have also been charac-terized from the infrared spectra of many solid ammines. The influence ofoxidation state of the metal and of other ligands present on these vibrationshas been examined.227 The spectrophotometric study of complex ions infused salts represents an interesting development.Several transition-metalchlorides were dissolved in fused potassium nitrate-lithium nitrate melts at184"; chloro-complexes are formed on addition of potassium chloride, andattempts to follow the spectral changes involved were quite successful.228The infrared spectra of cobalt (111) complexes containing groups (SO,2-,COZ2-, C2042-, CH,=CO,-) which can co-ordinate as unidentate or bidentateligands have been compared. The lowering of symmetry of the ligand, orthe frequency shifts are more pronounced in the bidentate state.229 Workon multident ate ligands has been developed.230 The tris-salicylidene andtris-( 2-pyridylmethylene) derivatives of 2-aminomethyl-1 : 3-diaminopropanefunction as sexadentate chelate compounds with cobalt (111) and iron(II1).221 R.J. Irving and E. A. Magnusson, J., 1957, 2018.222 J. GaEo, Chern. Zvesti, 1957, 11, 7 .223 D. Banerjea, F. Basolo, and R. G. Pearson, J . Amer. Chem. SOC., 1957, 79, 4055.224 R. G. Pearson, P. M. Henry, and F. Basolo, ibid., pp. 5379, 5382.225 G. B. Bokii and G. A. Kukina, Krystallografiya, 1957, 2, 400.226 B. M. Gatehouse, S. E. Livingstone, and R. S. Nyholm, J., 1957, 4222.227 G. F. Svatos, D. M. Sweeny, S. Mizushima, C. Curran, and J. V. Quagliano,228 D. M. Gruen, J . Inorg. Nuclear Chem., 1957, 4, 74.229 K. Nakamoto, J. Fujita, S.Tanaka, and M. Kobayashi, J . Amev. Chem. SOC,.230 F. Lions and K. V. Martin, ibid., p. 1572, 2733.J . Amer. Chem. SOC., 1957, 79, 3313.1957. 79, 4904124 INORGANIC CHEMISTRY.The compounds have not yet been resolved into their optically activeantipodes.231 The complex-forming tendency of tetraethylenepentaminewith the cobalt(11) ion indicates that all five of the amino-groups co-ordinate,and the sixth position can be occupied by such groups as H,O, CH,*OH, orthe OH- ion.232 The stability constants for the corresponding nickel@)complex have been determined.233 In the complexes of copper(I1) withtrie thylenet etramine, te trae thylenepen tamine, and pent ae t hylenehexamine,the copper ion has an amine co-ordination number of five.234(b) Carbortyls.A new method for the preparation of chromium hexa-carbonyl employs readily available starting materials. Chromic acetyl-acetone complex, or chromic and chromous salts of organic acids (e.g., acetic)in pyridine are reduced readily to the hexacarbonyl at 80-170" in thepresence of powdered zinc or magnesium, and under a pressure of 100-300atm. of carbon monoxide. Soluble chromium compounds being used, theyield is 80-90%.235 In contrast to the behaviour of dimeric carbonyls, themonomeric chromium, molybdenum and tungsten carbonyls are decomposedon reaction with alkali metals in liquid ammonia: 236M(CO), + 2Na __t Na,[M(CO)51 + COMore than three of the six CO groups in these carbonyls are usually difficultto replace. However, o-phenylenebisdimethylarsine (Diarsine) reacts withthe hexacarbonyls (4-6 hours at 150" in an evacuated tube) to giveM(COj,(Diarsine) and M(CO),(Diarsine),, but replacement of the two re-maining CO groups is much more difficult.A complete X-ray study of bis( cyclopentadienylmolybdenum tricarbonyl)rules out the earlier structure in which the metal atoms and ring centreswere in the sequence C,H,-Mo-(CO),-Mo-C,H, on a straight line normal tothe plane of a ring of six CO groups.The molecule has structure (22) with aThe products are stable in( 2 3 ) ( 2 2 )Mo-Mo &stance of 3.32 A. None of the CO groups is a bridging group, andthis is the first well-established case in this class of compound in which ametal-metal bond provides the only link between the two halves of a bi-nuclear compound.In this structure the metal atoms follow the effectiveatomic number231 F. P. Dwyer, N. S. Gill, E. C. Gyarfas, and F. Lions, J . Anzer. Chem. SOL, 1957,23? H. B. Jonassen and F. W. Frey, ibid., p. 2454.218 H. B. Jonassen and L. Westerman, ibid., p. 4275.234 H. B. Jonassen, J. A. Bertrand, F. R. Groves, and R. I. Stearns, ibid., p. 4279;235 G. Natta, R. Ercoli, F. Calderazzo, and A. Rabizzoni, J . Amer. Chem. SOL,236 H. Behrens and R. Weber, 2. anorg. Chem., 1957, 291, 122.237 H. L. Nigam and R. S. Nyholm, Proc. Chem. SOL, 1957, 321.238 F. C. Wilson and D. P. Shoemaker, J. Ghem. PAYS., 1957, 27, 809.79, 1269.B. ICirsrn, Bull. SOC. chim. France, 1957, 1178.1957, 79, 3611ADDISON AND GREENWOOD : THE TIIAKSITIOB ELEMENTS 125X-Ray diffraction also shows that the structure previously postulated formanganese and rhenium carbonyls, Mn,(CO) and Re,(CO) which in-volved two bridging CO groups, is incorrect. The molecules have structure(23), with direct metal-metal bonds, and there are no bridging CO groups.The octahedron round one metal atom is rotated by 45" with respect to theother.239 The reactions of manganese carbonyl have been further in-vestigated.=(' It resembles the corresponding rhenium compound in theformation of monomeric halogen derivatives Mn(C0) ,Hal.In alkalinesolution, compounds of the [Mn(CO) 5j- ion such as the tris-o-phenanthroline-nickel(I1) salt fli(C12HsN2)3] [Mn(CO),] , are readily isolated. Reaction withsodium in liquid ammonia gives Na+[Mn(CO),]-, and the carbonyl hydrideMn(CO),H is obtained by usual methods.This melts at -20", and sublimesi n vacuo below its m. p. Treatment with diazomethane gives the methylester Mn(CO),CH, as a colourless, stable, diamagnetic compound, m. p. 95".Corresponding benzyl (m. p. 38"), acetyl (m. p. 54"), and benzoyl (m. p. 95')derivatives have been described.=l With the substituted phosphines,arsines, and stibines, manganese carbonyl gives products such asMn(CO),(PR,) ; these are monomeric and paramagnetic (= one unpairedelectron) in contrast to the cobalt compound [Co(CO),(PPh,)] which is adiamagnetic dimer. With many non-ionic ligands (ammonia, isonitriles,triphenylphosphine) rhenium chloropentacarbonyl gives derivatives of thetype [Re(CO),(NH,) ,]C1; potassium cyanide gives the analogous complexK [ Re (CO), (CN) ,] .242Suggestions regarding the structure of iron dodecacarbonyl, Fe,(CO) 12,have been made on the basis of its infrared spectrum 243 and X-ray ana1ysis.wThe structure is not yet finally settled, and there is still doubt as to therelative positions of the iron atoms and the nature of the Fe-Fe bonding.Complex ruthenium carbonyl iodides can only be obtained in the presenceof other ligands which are bonded to the metal by mesomeric double bonds.245For instance, the polymeric, diamagnetic compound [Ru(CO) 21,] givesproducts of the type [RuX,(CO) with pyridine and triphenylphosphine,and K,[Ru(CO)~(CN),I,] by reaction with potassium cyanide, butundergoes total substitution of CO by aromatic isonitriles, giving, e.g.,Many reactions of iron carbonyls have now been satisfactorily interpretedon the basis of the formation of carbonyl fe~-rate,,~~ e.g., in alcoholic alkali:Fe8(CO)lp 4- 40H-+ EFe3(C0),,I2- + C0,2- 3- 2H,Oand reactions of iron dodecacarbonyl in alcoholic solution depend upon theprimary disproportionation3Fe3(C0)1z + MeOH __t [Fe(MeOH>~JIFeS(CO),,l + 5Fe(CO),[Ru(p-CN*C6H4*O*CH,)4I2] -238 L.F. Dahl, E. Ishishi, and R. E. Rundle, J . Chem. Phys., 1957, 26, 1750.240 W. Hieber and G. Wagner, Z. Naturforsch., 1957, 12b, 478.241 R. D. Closson, J. Kozikowski, and T. H. Coffield, J . Org. Chem., 1967, 22, 598.242 W. Hieber and L. Schuster, 2. anorg. Chem., 1956, 287, 214.243 F. A.Cotton and G. Wilkinson, J . Amer. Chem. SOC., 1957, 79, 762.244 L. F. Dahl and R. E. Rundle, J . Chew. Phys., 1957, 26, 1751; 27, 323; 0. S.245 W. Hieber and H. Heusinger, J. Inorg. NucEear Chem., 1957, 4, 179.246 W. Nieber and G. Brendel, Z. anorg. Chem., 1967, 289, 324, 338.Mills, Chem. and Ind., 1957, 73126 INORGANIC CHEMISTRY.Similarly with ethylenediamine, direct substitution of the normal carbonylsto give, e.g., Fe,(CO),en,, is believed not to occur. Rather, the compoundobtained depends on t e m p e r a t ~ r e , ~ ~ and the reaction follows the schemeFe dC0) I Z+ en --+ [Wen) 31 [Fe 3(CO) 1 --t [Wen) ,I[Fe,(CO)40" 90"145"____I) [Wen) 31 [Fe(CO) 41The compound E'e(CO),(NH,)2, believed to be formed by the action of gaseousammonia in the presence of pyridine at 65", has in fact the compositionFe,(CO),(NH,),, and its properties show it to be [Fe(NH,),][Fe,(CO)8].218The well-known o-phenanthroline derivatives of Fe,(CO) are not directsubstitution products.In acetone or benzene solution at 80" the product is[Fe(phen),] [Fe,(CO),] ; in pyridine at higher temperatures the compound[Fe(phen),] [Fe,(CO) is produced. This way of representing the compoundsis supported by their electrical conductivity and reactions.249 They resemblethe products formed by reaction of metal-cobalt carbonyls with ammonia,250e*g. JHg[Co(CO)J, + 12NHS __t 3Hg + ~[CO(NH~),][CO(CO),], + 8COConipounds containing the cobalt carbonyl anion are being prepared inincreasing complexity. An organotin compound is formed by the reaction 251Sn(C4HJzCIz + 2Na[Co(CO)J __t NaCl + [Sn(C,H~),][Co(CO>,],and from an ethereal solution of this product, triphenylphosphine precipitatesyellow crystals of constitution [Sn(C,H,) ,] [Co(CO),(PPh,)] 2.Several new substituted phosphine derivatives of cobalt and rhodiumcarbonyls have been prepared.The compound [(RNC),Co]+[Co(CO),]-,formed by reaction of Co,(CO), with aromatic isonitriles, is already known;by an analogous reaction with triphenylphosphine, the compound[(PPh,)2Co(CO),]+[Co(CO),]- is formed which retains 5-co-ordination in thecati0n.~52 Rhodium(1) is isolectronic with palladium(II), and also formsstable complexes in which the low valency state is stabilized. Rhodiumcarbonyl chloride reacts as follows :[Rh,(CO)4CIJ + 4L __t 2[RhL,(CO)CI] + 2CO(where L = Ar,P, Ar,As, or Ar,Sb) to give products of high thermal stability;they are monomeric, diamagnetic, and non-electrolytes. The triarylphosphites [L = (PhO),P, (9-C,H,Me*O),P, or ($-C6H4C1*O),P] reactsimilarly. The products resemble, but are less stable than, the triaryl-phosphine compounds, and in contrast give complexes of the type [RhL,ClJwith excess of triaryl p h o ~ p h i t e .~ ~ ~247 W. Hieber, J. Sedlmeier, and R. Werner, Chem. Ber., 1967, 90, 278; ?V. Hieber248 W. Hieber and R. Werner, ibid., p. 11 16.249 W. Hieber and J. G. Floss, ibid., p. 1617.260 W. Hieber and R. Breu, ibid., p. 1259.251 W. Hieber and R. Breu, ibid., p. 1270.252 A. Sacco, Atli Accad. naz. Lincei, Rend.Classe Sci. jis. mat. Itat., 1956, 21, 442.253 L. Vallarino, J., 1957, 2287, 2473.and R. Werner, ibid., p. 286ADDISON AND GREENWOOD: THE TRANSITION ELEMENTS 127A range of olefin chelate complexesof platinum, of the type [(diene)PtX,] where X = halogen, has now beendescribed. The stabilities of the complexes are in the order cycloocta-1 : 5-diene-dicyclopentadiene > dipentene > hexa-1 : 5-diene. The stabili-ties of the dihalides decrease in the order Cl > Br > I, in accord withthe increasing trans-effect of the halogens C1 < Br < I.254 All the halidecomplexes are monomeric, and are formulated as in (24). Palladium(I1)(c) Olefin and acetylene complexes.forms a similar range of olefin chelate complexes. In general, they have thesame structures, but are more deeply coloured, more easily formed, and morereactive than the corresponding platinum(I1) complexes.255 Withrhodium(I), chloro-bridged complexes [(diene) ,Rh,Cl,] are obtained, andthe cycloocta-1 : 5-diene compounds are again the most stable.Aminesreact with halogeno-bridged dimers to give mononuclear complexes[C,H,,(am)Rh*X] and there are related cationic and anionic rhodium(1)complexes of the type [C,H,,(diamine)Rh] + and [C,H,,RhCl,]-. A bi-nuclear acetate [(C,H,,) ,Rh,(OAc) ,] is obtained by boiling an acetonesolution of the chloride with potassium acetate. The acetate groups replacethe bridging chlorine atoms, and are symmetrically Butadienecompounds of platinum(II), palladium(II), and copper(1) halides have beendescribed; they include [PtC12,C4H6] ,, [PdC12,C4H,] ,, Cu,Cl,,C,H,, andCU2Br2,C4H6.The infrared spectrum of the palladium compound indicatesthat it is a butadiene-bridged dimer.257 Crystalline complexes [PtC12,C4H,] ,have been prepared by using both cis- and trans-but-%ene, and their infraredspectra show them to be different compounds. Decomposition of thecomplexes with sodium cyanide yields the respective isomeric olefin withoutrearrangement .258A new series of acetylene complexes of general formula [Pt (PPh,) Jac)],where (ac) = acetylenic substance, have been found to result from the reduc-tion of an alcoholic suspension of cis-[Pt(PPh,),Cl,] in presence of the acetyl-ene. They are more stable to air and moisture than are the well-known olefincomplexes of platinum(I1).The complexes increase in stability in the orderC,H, < AlkCiCH < C,(Alk),-Ph-CiCH < C,Ph, < C2(p-C6H4*N02)2. Theinfrared spectra of the complexes give no indication of the presence of atriple bond, but indicate rather that the bond has been reduced almost to adouble bond and the principal structure is probably that shown in (25).259Research on alkynyl complexes has continued. The nitrosyl group in254 J. Chatt, L. M. Vallarino, and L. M. Venanzi, J . 1957, 2496.255 Idem, ibid., p. 3413.256 J. Chatt and L. M. Venanzi, ibid., p. 4735.2 5 7 P. E. Slade and H. B. Jonassen, J . Amer. Chem. SOC., 1957, 79, 1277.258 H. B. Jonassen and W. B. Kirsch, ibid., p. 1279.259 J . Chatt, G. A. Rowe, and A.A. Williams, Proc. Chern. SOL, 1957, 208128 INORGANIC CHEMISTRY.the nitroprusside ion can be replaced by the acetylide ion by reaction withpotassium acetylide in liquid ammonia:KdFe(CN),NO] + KCzR + KNH,+ K,[Fe(CN),*C,R] + N, + H,O(where R = H, CH,, C,H,). The methyl and phenyl derivativesare stable, yellow, diamagnetic compounds. The acetylide compoundK,[Fe(CN),*C,H],NH, can be obtained only at low temperatures. Above-33" oxidation occurs to give a blue-black explosive dimerK, [ (NC) ,Fe-C C-C C-Fe (CN) ,I, 2NH,. 260 Manganous thiocyanate reactswith the potassium salt of acetylene, phenylacetylene, or propene in liquidammonia :4KC,Me + Mn(SCN), + K2[Mn(C2Me),] + 2KSCNThe tetra-alkynylmanganate(11) is pyrophoric but not explosive. Magneticmeasurements indicate five unpaired electrons, consistent with sp3 hybridiz-ation.With oxygen, the acetylene complex is readily oxidized to thehighly explosive rxanganese(II1) complex K,[Mn(C,H),] .261 Systems ofsilver nitrate and silver perchlorate with but-2-yneJ pent-2-yne, andhex-3-yne have also been studied ; solid complexes are formed.262(d) Aromatic complexes. The electronic structure of metal-aromaticcomplexes formed by the cyclopentadienyl radical and by benzene has beenfurther studied. A semi-quantitative theory of the bonding has beenproposed 263 which retains those parts of the previous theories of Jaffe,Dunitz and Orgel, and Moffitt and Ruch which are most appealingphysically. The magnetic moments of 24 such compounds have beendetermined.264 An interesting comparison arises in the aromatic reactivityof ferrocene and dibenzene-chromium.In the former, the C,H,- ionacquires aromatic character by virtue of its being an anion, whereas thechromium-benzene bonding can only detract from the aromatic characterof benzene. The following reaction occurs :AlClCr(CH8*CBH5)2 + 2CH,COCI LL CH,C6H,*COCH3 + 2HCI + Crand several other reactions of dibenzene- and ditoluene-chromium have beenexamined from the point of view of aromatic reactivity.265 Ultraviolet,visible, and infrared absorption spectra on dibenzene-chromium(1) iodidein solution and in the solid state indicate that the electronic state of thebenzene rings in [Cr(C,H,)dI involves very little aromatic character; thex-electrons of benzene are thus strongly attracted to the CrI ion.,66 Protonhyperfine structure is observable in the resonance spectrum of this cation,again indicating deep-seated hybridization of the x-orbitals of the rings andthe d-orbitals of the CrI atom.267 In contrast to the extreme resistance of260 R.Nast and I?. Urban, 2. anoi'g. Chem., 1957, 289, 244.261 R. Nast and H. Griesshammes, Chem. Ber., 1957, 90, 1315.262 A. E. Comyns and H. J. Lucas, J . Amer. Chem. SOC., 1957, 79, 4341.263 A. D. Liehr and C. J. Ballhausen, Acta Chem. Scand., 1957, 11, 207.264 E. 0. Fischer and U. Piesbergen, 2. Naturforsch., 1956, llb, 758.265 H. P. Fritz and E. 0. Fischer, ibid., 12b, 67.266 S. Yamada, H. Nakamura, and R. Tsuchida, Bull. Chem. SOC. Japan, 1957,30,647.2 6 7 R.D. Feltham, P. Sogo, and M. Calvin, J . Chew. Phys., 1957, 26, 1354ADDISON AND GREENWOOD : THE TRANSITION ELEhfEKiTS. 129ferrocene to catalytic reduction, cleavage to metallic iron and cyclopentadieneis readily achieved by using lithium in ethylamine. This is of value inassigning structures to isomeric substituted ferrocenes.268Following the isolation of dibenzene complexes of chromium, molyb-denum, and tungsten, analogous compounds of other transition metals havenow been prepared. By using the system VC1,-A1C1,-A1-C6H6, red-brown[Vo(C,H,) 2] has been 0btained.26~ Its paramagnetism corresponds to oneunpaired electron, indicating a " Doppelkegelstruktur ". It can be sublimedin a vacuum at 120-150" and its m. p. (277") is near that of [Cr(C&6)2](m.p. 284"). A new preparation of the dibenzene-chromium cation employsreaction between phenylmagnesium bromide and chromyl chloride orchromium trichloride. Reduction of the tetraphenyl borate or picrate withhypophosphorous acid gives [Cro(C6H6) 21 (m. p. 282-284') identical withthat prepared by using benzene.270 By reactions in the systemReC1,-AlC1,-Al-mesitylene under reflux a t 130" (or in a bomb tube ifbenzene is used), the cations [Re(C,H,) 2]+ and [Re(C,H,Me,) 2]+ are obtained.They are diamagnetic and isoelectronic with the uncharged [Cro(C6H6) 23,which is no doubt responsible for the failure to reduce these rhenium(1)complexes to the uncharged state.271 Reactions with the systemRuC1,-A1C1,-Al-rnesitylene give pale yellow products containing the cation[Ru(C,H,Me,) 2]2+.Its diamagnetism has been confirmed by examinationof its slightly soluble salts with BPh,- and PI?,- anions.272The synthesis of a mixed sandwich complex in which a C5H5- and aC,H, ring are co-ordinated to the same metal atom is of particular interest.273In view of the stability of [Re(c6H6),]+, it was to be expected thatsubstitution of one C,H6 ring by C,H5- might give a highly stable, electricallyneutral complex. Such a preparation has in fact been achieved in the caseof manganese; reaction of phenylmagnesium bromide with methylcyclo-pentadienylmanganese chloride gives red crystals (m. p. 116-118") of thecompound [Mn(MeC,H,) (c,H,)]. On treatment of cyclopentadienyliron di-carbonyl chloride with aluminium trichloride in refluxing mesitylene, carbonmonoxide is lost and hydrolysis in the presence of iodide gives the closelyrelated compound [Fe(C,H,) (C6H3Me,)]+I-. The following group of com-pounds is therefore now available :[Cr(C6H CRe(C6H J EFe(C*H,Me,),12+1: M n (C 5 H 4 M 4 (C 6 H 611 I: Ru (C 6 H 3 Me 3) 21 2+[WC, H6)21[Fe(C5H5)(c6H s ~ e , ) i +Each has the same sandwich structure and the same electron distribution inthe metal atom.,4 detailed account has now been published of the work leading to therepresentation of Hein's polyphenylchromium compounds as sandwich268 D.S. Trifan and L. Nicholas, J . Amer. Chem. SOC., 1957, 79, 2746.2 1 3 ~ E. 0. Fischer and H. P. Kogler, Chem. Ber., 1957, 90, 250.270 H.H. Zeiss and W. Henvig, J . Anzer. Chem. Soc., 1956, 78, 5959.271 E. 0. Fischer and A. Wirzmuller, Chem. Ber., 1957, 90, 1725.272 E. 0. Fischer and R. Bottcher, 2. anorg. Chem., 1957, 291, 305.273 T. IT. Coffield, V. Sandel, and R. D. Closson, J . Amer. Chem. SOC., 1957, 79,6826.REP.-VOL. LIV 130 I N OHG AN IC CI3 E MISTKY.complexes in which the Cr atom lies between diphenyl-diphenyl or diphenyl-benzene planes. This has dispelled much of the confusion associated withthe structure of these compounds.274 The mercuric iodide complex de-composes on heating according to the equation 2T5The preparation of benzodiphenylchromium compounds by a Grignarcimethod, and some chemical properties, have been described.,76The Scandium Group and Lanthanides-The thermal decomposition ofchloride hydrates of Y, Sc, La, Ce, Pr, Nd, Sm, and Gd has been studied inthe thermobalance. The oxychloride MOCl is produced except in the casesof scandium and cerium, which give Sc,O, and CeO, re~pectively.~~' Inexperiments in which tri-n-butyl phosphate (TBP) was used to extract andseparate yttrium and the lower lanthanides, extractability was found toincrease with atomic number (La- Gd).Experiments with varying con-centrations of tributyl phosphate indicated the formation of Y (NO3),,3TBP,and the corresponding cerium and europium compounds.278 Over the fulllanthanide range (2 = 57-71) the extraction into tributyl phosphate fromaqueous nitric acid passes through a maximum at 2 = 64, so that the " half-filled shell " effect operates here as in ion-exchange separations.279 Thenitrides SmN, EuN, and YbN have been prepared by direct combination;each has the NaC1-type structure.Differential thermal analysis of SmN inmoist nitrogen indicates the formation of SmO(0H) at 250-375°.280 Thelattice constants of the lanthanide nitrides vary regularly with atomicnumber except for GdN, which is high.281 In contrast to the earlier lanth-anides, for which the sulphides M,S, involve M3+ ions only, the chemicalreactions of the samarium sulphide Sm,S, appear to justify its representationas Sm,S,,SmS, thus involving Sm2+ ions.282Ceric tert.-alkoxides Ce(OR), (where R = CMe,, CMe,Et, CMeEt,,CEt,, CMe,Prn, CMe,Pri, and CMeEtPr") have been prepared fromCe(OPri),,PriOH by alcohol interchange.The tert.-butoxide and tert.-amyl-oxide are deep yellow sublimable solids. The higher tert.-alkoxides arebright yellow liquids which distil unchanged, and are the first volatile liquidcompounds of cerium(1v) to be reported.283 A reinvestigation of thepraseodymium oxides by X-ray diffraction has shown the presence of atwo-phase system in the region PrOl.,,-Pr02, at temperatures above 350"and pressures above 10 atm. Oxidation of Pr,O,, at temperatures up to760" and pressures up to 331 atm. gives Pro, and/or Pro1.,,, with no evidence274 H. H. Zeiss and M. Tsutsui, J . Amer. Chem. SOC., 1957, 79, 3062.275 F. Hein and E. Kurras, 2. anorg. Chem., 1957, 290, 179.2 7 6 F. Hein, P. Kleinert, and E. Kurras, ibid., 289. 229.2 7 7 W.W. Wendlandt, J . Inorg. Nuclear Chem., 1957, 5, 118.278 D. Scargill, K. Alcock, J. M. Fletcher, E. Hesford, and H. A. C . McKay, ibid.,2 7 9 D. F. Peppard, W. J. Driscoll, R. J. Sironen, and S. McCarty, ibid., p. 326.280 H. A. Eick, N. C. Baenziger, and L. Eyring, J . Amer. Chem. SOC., 1956, '78, 5987.z81 W. Klemm and G. Winkelmann, 2. anorg. Chem., 1956, 288, 87.282 M. Picon and J. Flahaut, Compt. rend., 1956, 243, 2074.288 D. C. Bradley, A. K. Chatterjee, and W. Wardlaw, J., 1957, 2600.4, 304ADDISON AND GREENWOOD : THE TRANSITION ELEMEKTS. I31of an intermediate phase.284 Data on the complex-formation of CeIlI, LaTLL,and GdlIr by fluoride ions in solution can be interpreted satisfactorily byassuming only the presence of the simplest complex MF2+.285Europium and ytterbium metals dissolve in liquid ammonia at -78" togive characteristic blue solutions.Evaporation of the solutions left goldenmetallic crystals, presumably of the metal hexa-ammines. Samarium isinsoluble.286 The heat of formation of the holmium oxide Ho203 is-449.5 kcal./mole; this value lies midway between known values fordysprosium and erbi~m.~87 The five lanthanide elements immediatelypreceding thulium have similar vapour pressures, but measurements onthulium at 809-1219" K indicate a high vapour pressure. The heat ofsublimation is 57.4 kcal./mole. This enhanced volatility (which is stillhigher in ytterbium) is attributed to the approach towards the filling of the4f electron shell.288The Titanium Group.-The trialkoxy-titanium compounds (RO),Tioxidize in air to give dialkoxytitanium oxides (RO),TiO.Under suitableexperimental conditions, a current of dry oxygen being used, hexa-alkoxy-dititanoxanes (RO),Ti*O*Ti(OR), can be obtained. Thus the main productof oxidation of triethoxytitanium is (EtO) 6Ti20.289 Attempts to preparetitanium tetra-acetate by treatment of the tetrachloride or its alkoxides withacetic anhydride resulted in formation of the basic triacetate [T~(OAC),],O.~~~The crystal structure of the simple compound TiOS0,,H20 is built up from-Ti-O-Ti-O- chains held together by sulphate groups.291 The nature ofthe alkyl group has a significant influence on the hydrolytic behaviour oftitanium alkoxides, Ti(OR),. There is a remarkably low degree of poly-merization in the products of hydrolysis in alcohols of high boiling point.292The equilibrium between titanium di- and tri-chlorides and titaniummetal, in the presence of a NaC1-KC1 melt, is such that Ti2+ is thepredominant species, representing 90% of the dissolved titanium.The Ti4+content of melts equilibrated with titanium metal is negligible.293 Methodsof preparation of titanium(II1) oxychloride have been re-examined.Titanium trichloride reacts with quartz at 600" (50, + 2TiC13---t2TiOC1+ SiC1,) and the oxychloride is not volatile even under vacuum atred heat.294 X-Ray and infrared studies on addition compounds oftitanium tetrabromide with 1 : 4-dioxan, tetrahydrofuran, and tetra-hydropyran indicate that the ether oxygen atoms are involved in thebonding.The C-0-C ring stretching frequency in the infrared spectrum of284 C. L. Sieglaff and L. Eyring, J . Anzer. Chem. SOG., 1957, 79, 3024.285 J. W. Kury, 2.2. Hugus, jun., and W. M. Latimer, J . Phys. Chem., 1957,61, 1021.2 8 6 J. C. Warf and W. L. Korst, ibid., 1956, 60, 1590.E. J. Huber, jun., E. L. Head, and C. E. Holley, jun., ibid., 1957, 61, 1021.288 F. H. Spedding, R. J. Barton, and A. H. Daane, J . Amer. Chem. SOC., 1957,289 A. N. Nesmeyanov, 0. V. Nogina, and R. K. Freidlina, Bull. Acad. Sci. U.S.S.R.,290 K. C. Pande and K. C. Mehrotra, Chew. aptd Igtd., 1957, 114; %. aiiovg. Chew.,291 G. Lundgren, Arkiu Kemi, 1957, 10, 397.292 D. C. Bradley, R. Gaze, and W. Wardlaw, J., 1957, 469.293 W. C . Kreye and H.H. Kellogg, J . Electrochenz. SOL., 1957, 104, 50-4.294 H. Schafer, E. Weise, and F. Wartenpfuhl, Angew. Chem., 1957, 69, 479.79, 5160.1956, 3, 355.1957, 291, 97132 INORGANIC CHEMISTRY.dioxan is absent from the spectrum of the compound TiBr4-dioxan.,96 Therange of monocarboxylic esters which form addition compounds withtitanium tetrachloride has been extended to include n-butyl and isopentylformat e , qz-bu t yl chloroacet at e , and some esters of t richloroacet ic acid. 86The properties of zirconium tetrachloride in non-aqueous media POCl,,SOCl,, NOCl, and SeOC1, have been examined ; the compounds ZrCl4,2POC1,,ZrC1,,SOCl2, ZrC14,2NOC1, and ZrC1,,2SeOC12 are formed in solution. Withtypical bases, chlorozirconates such as (R4N) 2[ZrC16] are formed.WithSbCl, in phosphorus oxychloride medium, a compound ZrC14,SbC15 is ob-tained as its bright yellow solvate ZrCl4,SbC1,,2POC1,, and electrolysisindicates that the ions ZrC13+ and SbC1,- are present.297 When zirconiumand hafnium tetrachlorides are heated together with zirconium powder in avacuum at 400450", zirconium tetrachloride is reduced to the com-paratively involatile trichloride. Hafnium tetrachloride is not reduced, andcan be removed by sublimation. Zirconium trichloride dispropoitionates at550', yielding the tetrachloride again, and the process therefore has possi-bilities as a separation technique.298 Thorium metal dissolves in alkalichloride melts containing thorium tetrachloride, and at 500-900" Th4+ isreduced to Th2+.Equilibrium constants have been evaluated.299 There isalso chemical and magnetic evidence for the formation of thorium(I1) andthorium(1) iodides, as well as ThI,, in the reduction of ThI, by metallicthoriurn at 550°.300The extraction of zirconium nitrate from aqueous solutions by tributylphosphate (TBP) in the presence of uranyl nitrate, has been examined.Partition coefficients fall considerably on addition of kerosene to thesystem.301 Thorium nitrate is extracted into tributyl phosphate as adisolvate Th(N0,),,2TBP. It is more readily extracted than are thelanthanides, but less extractable than plutonium(1v) nitrate by a factor often.30,The Vanadium Group.-It has been found that vanadium pentafluoridecan be prepared, purified, and examined in all-glass systems provided thatmoisture and grease are rigidly excluded, and further physical propertieshave been determined.It has m. p. 19-6" (cf. NbF, 80-0", TaF, 91.5') andb. p. (extrapolated) 48.3". Vapour pressures have been recorded over mostof this range. The postulate of self-ioniz-ation 2VF5 __1L VF,+ + VF6- in the liquid is supported by specific con-ductivity (2.4 x 104 at 25'). Vanadium pentafluoride VF, is more effectivethan iodine pentafluoride IF5 as a fluorinating agent, and gives carbontetrafluoride on reaction with the tetrabromide or tetraiodide.,03 TheThe Trouton constant is 33.1.295 R. F. Rolsten and H. H. Sisler, J . Amer. Chem. SOC., 1957, 79, 1068, 1819.296 Yu. A. Lysenko, Zhuv. obshchei Khirn., 1956, 26, 2963, 3273.297 V.Gutmann and R. Himml, 2. anorg. Chem., 1956, 287, 199.298 I. E. Newnham, J . Amer. Chem. SOC., 1957, 79, 5415.299 M. V. Smirnov and L. Ye. Ivanovskii, Zhur. $2. Khim., 1957, 31, 802.soO G. W. Watt, D. M. Sowards, and S. C. Malhotra, J . Amer. Chem. SOC., 1957,301 I<. Alcock, (the late) F. C. Bedford, W. H. Hardwick, and H. A. C. McKay,302 E. Hesford, H. A. C. McKay, and D. Scargill, ibid., p. 321.303 H. C. Clark and H. J. Emel(.us, J . , 1957, 2119.79, 4908.J . Inorg. Nuclear Chern., 1957, 4, 100ADDISON AND GREENWOOD : THE TRANSITION ELEMENTS. 133species present in the vapour phase is the monomer VF5.304 Reaction ofvanadium tetrachloride with the amines dimethylamine and trimethylaminein 2-methylheptane solution gives mainly 1 : 1 adducts VCl,,NHMe, andVCl,,NMe,, which are stable up to 150" and are compounds of pentaco-ordinate vanadium.At high dimethylamine concentrations a base-catalysed elimination of hydrogen chloride occurs :VCI,,NHMe, __t VCI3,NMe, VCI,(NMeJ,The compounds VCl,(NHMe) ,,NH,Me, and VCl,(NMe,) , were also isolated.305Aliphatic amines react with niobium pentachloride. With dimethylamineat -78", elimination of HC1 occurs to give NbC1,(NhIe2)2,NHMe, whichloses a dimethylamine molecule in nitrobenzene solution. At room tem-perature, mono- and tri-methylamine give NbCl,(NHMe), and NbC1,,2NMe3 ;the former is largely dimeric in nitroben~ene.~06 The b. p.s of niobium andtantalum pentachlorides are 247.4" and 232.9", and the heats of vaporization12.6 and 13.1 kcal./mole, respectively.From a study of liquid-vapourequilibrium in this binary system, the relative volatility (TaC1,/NbC15) isfound to be 1.36 at atmospheric pressure over the full composition range.307The reductions of NbCl, to NbC1, and TaC1, to TaCl,, have been accomplishedby using hydrogen in an electric discharge. Tantalum tetrabromide isobtained in this way from the pentabrornide; the disproportionationTaBr, TaBr, + TaBr, occurs in a vacuum at 300". In contrast,niobium pentabromide is reduced under the same conditions to the di-br~mide.~O~ Contrary to previous belief, niobium pentaiodide begins to beformed from the elements at 250", and is formed rapidly at 280".309A double oxide U2Ta20, (formed by heating UO, with Ta,O,) has beenidentified from its X-ray diagram.310 The non-stoicheiometric compoundLi,,,V,O, is monoclinic; the structure is formed from VO, octahedra andVO, trigonal bipyramids grouped as sheets by sharing edges and corners.The sheets are held together by Li+ ions in octahedral inter-layer sites, andmore are located in additional tetrahedral positions.311 From the ultravioletspectra of the solutions, three peroxy-niobium complexes have been recog-nized in sulphuric acid solution.The Nb : H20, ratios are 2 : 3 in con-centrated acid, 1 : 2 in acid concentrations down to 60%, and 1 : 1 in diluteacid or neutral solution 312 Ternary phosphides and arsenides ofvanadium(v), Li,VP, and Li,VAs,, have been prepared which are analogousto the nitride Li,VN, recently described.313Published work on protactinium chemistry has been concerned largelywith separation processes.These are important as a means of isolating304 L. E. Trevorrow, J. Fischer, and R. K. Steunenberg, J . Amer. Chem. SOC., 1957,3 0 5 G. W. A. Fowles and C. M. Pleass, J., 1957, 1674.306 Idem, ibid., p. 2078.307 J. B. Ainscough, R. J. W-. Holt, and F. W. Trowse, ibid., p. 1034.308 V. Gutmann and H. Tannenberger, Monatsh., 1956, 87, 769.309 R. F. Rolsten, J . Anzer. Chem. SOC., 1957, 7'9, 6409.310 M. Gasperin, Compt. rend., 1956, 243, 1534.311 A. D. Wadsley, Acta Cryst., 1957, 10, 261.312 N. Adler and C. F. Hiskey, J . Amer. Chem. SOL, 1957, 79, 1827, 1831, 1834.31s R. Juza and W. Uphoff, Angew. Chem., 1957, 69, 96.79, 5167134 INORGANIC CHEMISTRY.protactinium, and also because 233Pa is an intermediate in the formation of233U from 232Th.The extraction of 233Pa from 1M-nitric acid solutioncontaining 2% of oxalic acid, into mono-, di-, and tri-butyl phosphates hasbeen compared. The distribution ratios (organiclaqueous phase) are 8.1,100.0, and 0.049 respectively, so that dibutyl phosphate is the active complex-forming agent. Protactinium is separated from thorium and fission productsby precipitation with niobium compounds; it is then separated from theniobium by extraction into dibutyl hydrogen pho~phate.~l~ Experimentshave also been described on the purification of 231Pa by chromatography andpaper electroph~resis,~~~ and on the solvent extraction of quadrivalent 233Pawith isobutyl methyl ketone and tributyl phosphate.316 Concentration of231Pa can be effected by recycling through Dowex-1 resin.After initialsorption from hydrochloric acid solution, it is eluted with an HC1-HFmixture. Addition of aluminium chloride or boric acid to the effluentrenders the protactinium readsorbable by the resin. Re-elution withHCI-HF mixture then produces a marked concentration of the pro-ta~tinium.~~' For exhaustive chemical study, the long-lived 231Pa is to bepreferred to the more active 233Pa. Only very small quantities have hithertobeen separated. One of the best sources has been found to be the residuesfrom the processing of uranium minerals, which are available in ton quantitiesand contain 0.1-0.3 p.p.m.of protactinium. A method has been describedfor the recovery of more than 90% of this in high purity. It consistsessentially in dissolution of the source material in acid, concentration ofprotactinium by precipitation with an internal silicate carrier, and finalisolation by ion e~change.~1* Protactinium is now becoming available inlarger quantities, and rapid developments in its chemistry are expected inthe near future.The Chromium Group.-Aqueous chromic acid solutions in closed con-tainers at 300-325" evolve oxygen. At oxygen pressures of 50-200 atm.the solid decomposition products are CrO, and HCrO, [or CrO(OH)]. Thelatter is dehydrated to Cr20,; 319 its structure consists of distorted (CrOJ9-octahedra, each sharing six edges with coplanar octahedra to form continuoussheets, which are stacked so that oxygen atoms are superimposed, withhydrogen ions between.These symmetrical hydrogen bonds are uniqueamong known isoformular stru~tures.~~O When heated in a melt ofpotassium hydroxide and water (5 : 1 wlw) and in the absence of oxygen,potassium chromate forms a clear green solution which contains quinque-valent chromium as the hypochromate ion Cr02-.321 The structure of blue" perchromic acid " is now resolved in favour of CrO, by spectrophotometryof aqueous methyl-alcoholic solutions and of aqueous solutions,322 and314 A. J. Fudge and J. L. Woodhead, Chew. and I n d . , 1957, 1122.315 M. Lederer and J. Vernois, Compt. rend., 1957, 244, 2388.316 G. Bouissibres and J. Vernois, ibid., p.2508.317 M. K. Barnett, J. Inorg. Nuclear Chem., 1957, 4, 358.318 M. L. Salutsky, K. Shaver, A. Elmlinger, and M. L. Curtis, ibid., 1966, 3, 289.ylo B. J. Thamer, R. M. Douglass, and E. Staritzky, J . Arne?. Ghem. SOC., 1957,K. M. Douglass, Acta Cryst., 1957, 10, 423.321 N. Bailey and M. C. R. Symons, J., 1957, 203.a22 D. F. Evans, ibid., p. 4013.79, 547ADDISON AND GREENWOOD: THE TRANSITION ELEMENTS. 135solutions in ethyl acetate.323 The predominant equilibrium in dilute aqueoussolution isA stable 1 : 10-phenanthroline-perchromic acid complex is known, theanalysis of which also supports the formula CrO,. The brown peroxideCr0,,3NH3 is a &peroxide of quadrivalent chromium.322 The products ofthe chromium trioxide-liquid ammonia reaction are complex ; they includeammonium chromate, hexamminochromium(II1) chromate, and an ammino-and a nitro-ammino-chromium(rI1) chromate polymer.324 About one quarterof the chromium(v1) is reduced to chromium(II1).An oxalato-complex of molybdenum, (NH4)4[M~(C204)4], 8H,O, has nowbeen obtained by electrolytic reduction of an ammonium molybdate solutionin the presence of oxalic acid.The product is soluble in water, insoluble inorganic solvents, and chars at 60". A carbonato-complex K,[Mo(CO,)~] hasbeen prepared by similar methods.325 The spectra of heteropolytungstatescontaining cobalt(II), cobalt(m), or manganese(1v) as central ions indicatethat the central structural unit is a tetrahedron MO,, not MO,.The polyanion [co111(w20~)6]g- is therefore now represented as[CO~~~O~(W,,O,,)]~-.~~~ Binary tungstates Fe,Mnl-zW04, where x = 0-25,0.41, and 0.66 have been synthesized and their lattice constants deter-mined.327 Non-stoicheiometric solids of the formula Cu,WO,, where x liesbetween 0.26 and 0.77, are prepared by electrolytic reduction of aCuW0,-WO, melt at 800".These materials are copper analogues of thealkali tungsten bronzes.328 By mass-spectrometric analysis, the polymericgaseous species formed during sublimation of MOO, have been identified asMo,O,, Mo,O,,, and M05015; corresponding species are formed in thesublimation of wo,.329Gaseous fluorine acts upon molybdenum hexacarbonyl in two differentways depending on temperature. Above 50°, a vigorous reaction givesMoF, and COF,.At -75", an olive-green solid results, which when heatedat 170" gives a distillate of the new pentafluoride MoF, (a yellow solid,m. p. 64") and a residue of MoF,.~~O Complex fluorides of quinquevalentmolybdenum and tungsten, involving the ions MoF,- and WF,-, have beenobtained from the hexafluorides by the reducing action of potassium iodidein liquid sulphur dioxide.=1The uranium hydride UH, has a dissociation pressure of 1 atm. at 430".Pressure-composition isotherms have now been measured at pressures up to65 atm. and temperatures up to 650". The heat of formation of UH, is- 30.3 kcal./mole, and is almost independent of temperature.332 HydrogenHCr0,- + 2H202 + H+--- CrO, + 3H20323 A. Glasner and M. Steinberg, J., 1957, 2569.324 R.S. Drago and H. H. Sisler, J . Amer. Chem. SOL, 1957, 79, 1811; S. I. Tannen-baum, R. S. Drago, and H. H. Sisler, ibid., p. 1815.325 M. C. Steele, Austral. J . Chem., 1957, 9, 367, 368.328 Y. Shimura and R. Tsuchida, Bull. Chem. SOC. Japan, 1957, 30, 502.327 Yu. P. Simanov and R. D. Kukshakova, Zhur. $2. Khim., 1957, 31, 820.32* I,. E. Conroy and M. J. Sienko, J . Amer. Chem. SOL, 1957, 79, 4048.329 J. Berkowitz, M. G. Inghram, and W. A. Chupka, J. Chewz. Phys., 1957, 28,330 R. D. Peacock, P ~ o c . Chern. Soc., 1957, 69.331 G. B. Hargreaves and R. D. Peacock, J., 1957, 4212.832 G. G. Libowitz and T. R. P. Gibb, jun., J. Phys. Chem., 1957, 61, 793.S42; 27, 85136 INORGANIC CHEMISTRY.selenide reacts with uranium tetrachloride at 620" to give a compoundUse,, which magnetic and chemical properties suggest is a polyselenide ofquadrivalent uranium.333 When this is heated in a vacuum at 580°, thediselenide Use, is obtained.334 A uranyl silicate hydrate (U0,)2Si04,3H20results from reaction of U02F2 solution with silica at 300°.335 Themechanism of hydrolysis of the U4+ ion has been studied by calorimetricmeasurements 336 on uranium tetrachloride, and by electrometric titrationin SM-sodium perchlorate solutions.337 The latter data are explained onthe basis of a mononuclear reaction U4+ + H20 + U(OH)3+ + H+, and apolynuclear product U[(OH),U],4*n.The hydrolysis of the uranyl ion isinterpreted in terms of two reactions, leading to the formation of monomericUO,*OH+ and the dimeric U02*U032+ ions.336During attempts to prepare uranyl alkoxides, it was observed that thedisproportionation 3UO,(OR), + U,O,(OR), + UO(OR), occurredreadily. This is unusual in view of the stability of the uranyl group.338The chemistry of uranium(v) alkoxides has been developed.From analcoholic solution of the thionyl chloride complex UCl,,SOCl,, the alcoholateUOCl,,EtOH can be isolated, and this is probably an intermediate in thereaction of the alcoholic solution with pyridine, when (C,H,N),,UOCl, isproduced. Reaction of this with alcohol and ammonia affords a novelmethod for the preparation of the penta-alkoxides U(OR),, which are surpris-ingly resistant to disproportionation and distil unchanged. The pentaiso-propoxide is a golden, crystalline Uranium(v) ethoxide behaves asan acid, and reacts with sodium, calcium, or aluminium ethoxides to givepounds of the type U(OR),Cl, U(OR),Cl,, and U(OR)&l, are produced byreaction of U(OR), with hydrogen chloride.340 Uranium(v1) ethoxide, adark-red distillable liquid, is formed by oxidation of Na[u(OEt),] withbenzoyl per~xide.~~l The structure of a range of penta-rt-alkoxides U(OR),,where R = Me, Et, Prn, Bun, TZ-C,H~~, has been examined.Except for thepentamethoxide, which is trimeric, they are all dimeric like the correspondingquinquevalent niobium and tantalum complexes.342The Trans-uranium Elements.-Reviews published during the year in-clude an account of the work carried out at the Radiation Laboratory,University of California, on the trans-curium elements.This deals chrono-logically with the development of the work, and the technical difficultiessalt-like compounds Na[U(OEt),], Ca[U(OEt)6]zY and AI[U(OEt)J,. COm-333 P. Khodadad and J. Flahaut, Gompt. rend., 1957, 244, 462.334 P. Khodadad, ibid., 245, 934.335 W. L. Marshall and J. S. Gill, J . Amer. Chem. SOL, 1957, 79, 1300.336 J. A. Hearne and A. G. White, J., 1957, 2081, 2168.357 S. Hietanen, Acta Chem. Scand., 1956, 10, 1531.338 D. C. Bradley, Amar K. Chatterjee, and Amiya K. Chatterjee, Proc. Chem. Soc.,3S9 D. C. Bradley, B. N. Chakravarti, and A. K. Chatterjee, J . Inorg. Nuclear Chem.,340 R. G. Jones, E. Bindschadler, D. Blume, G. Karmas, G. A. Martin, jun., J. R.341 R. G. Jones, E. Bindschadler, D. Blume, G. Karmas, G.A. Martin, J. R. Thirtle,342 D. C. Bradley and A. K. Chatterjee, J . Inorg. Nuclear Chem., 1957, 4. 279.1957, 260.1957, 3, 367.Thirtle, and H. Gilman, J . Amer. Chem. Soc., 1956, 78, 6027.1;. A. Yeoman, and H. Gilman, ibid., p. 6030ADDISON AND GREENWOOD : THE TRANSITION ELEMENTS. 137encountered.343 The chemistry of the trans-uranium elements up tomendelevium has been reviewed from the point of view of preparation,separations, and physical proper tie^.^^ The crystal structures of theactinide elements (and manganese) have been correlated; the existence ofcomplex structures may be related to the possibility of Jahn-Teller dis-tortions occurring in the body-centred cubic lattice.345 The principalspectroscopic and magnetic properties of uranyl-like ions are due to theadditional electrons in the 5f shell (one in neptunyl, two in the plutonyl ion,etc.) , and the absorption spectra, microwave resonance data and magneticsusceptibility of the plutonyl ion have been interpreted on this basis.346Neptunium metal has density 20.2 g./c.c.at 20"; the specific heat is0.0319 cal. g.-l deg.-l over the range 29-99', and this lies between knownvalues for uranium and plutonium. The metal is much harder than uranium,the ultimate tensile strength being about 80-90 tonslsq. Quadri-valent uranium rapidly reduces plutonium to the plutonium(II1) state innitric acid solution :3U4+ + ~ P u O , ~ + 3- 2H20 + 3U02+ + 2Pu3+ + 4H+This has applications in liquid-liquid extractions for uranium-plutoniumseparations, since Pu3+ concentrates in the aqueous phase.348 Plutonium(1n)nitrate is relatively inextractable by tri-n-butyl phosphate, but plutonium(1v)and plutonyl nitrates are readily extracted ; the compounds Pu(N0,),,2TBPand PuO,(NO,) ,,2TBP appear to be formed.Plutonium (like americium)can therefore be rendered extractable or inextractable by reduction oro x i d a t i ~ n . ~ ~ The magnetic susceptibility of the five plutonium(1v) com-pounds Pu (SO,) ,,4H20: Rb4Pu(S03,,2H ,O, Pu ( C204) 2,6H 20, (Me,N) iPuCl,,and PuF, has been measured. In each case a large departure from theCurie-Weiss law is observed.350 The plutonium(1v) alkoxide Pu(OPri),,mixed with its addition compound with pyridine, has been prepared fromthe complex (C,H,N) 2PuC1,.Crystallization of the isopropoxide frompropan-2-01 gives an emerald-green solvate Pu(OPri),,PriOH, analogous tothe zirconium, hafnium, and cerium compounds. Pure plutonium iso-propoxide sublimes at 220'/0-05 mm.351 The ions Pu3+, Pu4+, and PuOa2+form 1 : 1 chelate complexes with ethylenediaminetetra-acetic acid. Inthe first two cases, complexes with Pu : edta ratio of 2 : 1 are also formed.352The relationships between the various valency states of americium havebeen further studied. Americium-(v) and -(vI) undergo self-reduction, andkinetics have been studied in perchloric acid solution. Americium(II1) doesnot appear during simultaneous self-reduction and it is suggested thata43 S. G. Thompson, Sveszsk kern. Tidskr., 1957, 69, 359.344 P.Graf, Chimia (Switz.), 1957, 11, 57.345 L. E. Orgel, J . Phys. and Chem. Solids, 1957, 3, 50.346 J. C. Eisenstein and M. H. L. Pryce, Proc. Roy. Soc., 1956, A , 238, 31.a47 V. W. Eldred and G. C. Curtis, Nature, 1957, 179, 910.3a8 J. Rydberg, J . Inorg. Nuclear Chem., 1957, 5, 79.G. F Best, H. A. C. McKay, and P. R. Woodgate, ibid., 1957, 4, 315.W. B. Lewis and N. Elliott, J . Chern. Phys., 1957, 27, 904.351 D. C. Bradley, B. Harder, and I;. Hudswell, J., 1957, 3318.s62 J. K. Foreman and T. D. Smith, ibid., pp. 1762, 1758138 INORGANJC CHEMISTRY.americium(v1) reacts with the americium(1v) formed to give americium(v) .353The curium oxide CmO, is known; curium tetrafluoride has now been made,and in this compound the curium is also unequivocally quadrivalent.244Cm(half-life 18.4 years), in the form of CmF,, was treated with gaseous fluorineat 300-400”. The X-ray data show that CmF, has the same monoclinicstructure as have UF,, NpF,, PuF,, and AmF,.354 The existence of thiscompound shows that the stability of the half-filled 5f shell in curium ismarkedly less than that of the half-filled 4f shell in gadolinium, and em-phasizes that predictions of the valency of trans-uranium elements on thebasis of lanthanide analogy should be treated with caution. The separationof berkelium as the quadrivalent species has been described. Nitric acidsolutions being used against a ut-heptane solution of di-2-ethylhexyl hydrogenphosphate, the distribution coefficient for berkelium(1v) is lo6 times greaterthan for berkelium(II1) or curium(rI1).Under the oxidizing conditions used(KBrO, in 10~-HNO,), americium remains in the AmIII state.355 Theisotope 253Fm has been identified among the products of reaction of 252Cfwith 40 Mev a-particles. I t has a 4.5 day half-life, and is thus the longest-lived fermium isotope known (compare 250Fm 30 min., ,51Frn 7 hours,252Fm 30 hours). Only the undiscovered 257Fm is expected to have a longerhalf-life.356 Details are now available of the work leading to the preparationof a few atoms of element 102, carried out co-operatively by the UnitedStates, Great Britain, and Sweden. The name “nobelium” has beensuggested in honour of Alfred Nobel, and of the Institute at which the workwas carried out. Element 102 was made by bombarding 2MCm with90 Mev ions of 13C4+. The isotope produced had mass 251 or 253 (probablythe latter), formed by the nuclear reaction 244Cm(13C, 4 ~ ~ ) ~ ~ ~ 1 0 2 .Theproduct was collected by recoil; a new a-activity of 8.5 Mev was detected,though only 17 events of this energy were observed. When the productswere eluted from a cation-exchange column, the 8-5 Mev a-activity appearedat the position expected for element 102.357The Manganese Group.-Reduction of potassium permanganate bypotassamide, and the disproportionation of potassium manganate in liquidammonia, are of interest for their analogy with corresponding reactions inwater.358 From consideration of a thermodynamic cycle involving therhenide ion Re-, it is deduced that for stability this ion must exist as anoxygenated complex such as Re(H,0)4-.359 A simple technique wherebymetal oxides and carbon tetrachloride are heated at 400” in a sealed tube togive the anhydrous chloride has been applied to the preparation of tech-netium and rhenium compounds.The technetium product is a blood-red353 G. R. Hall and T. L. Markin, J . Inorg. Nuclear Chem., 1957, 4, 296; see alsoS. R. Gunn and B. B. Cunningham, J . Amer. Chem. Soc., 1957, 79, 1563.354 L. P. Asprey, F. H. Ellinger, S. Fried, and W. H, Zachariasen, J . Amer. Chewi.SOC., 1957, 79, 5825.355 D. F. Peppard, S. W. Moline, and G. W. Mason, J . Inorg. Nuclear Chem., 1957,356 S. Amiel, Phys. Rev., 1957, 105, 1412.357 P. R. Fields, A. M. Friedman, J. Milsted, H.Atterling, W. Forsling, L. W. Holm,and B. Astrom, ibid., 107, 1460; see also H. A. C. McKay and J. Milstead, Nature,358 T. Inoue, S. Takamoto, and S. Kurokawa, J . Chenz. SOC. Japan, 1951, 78, 274.359 J. W. Cobble, J . Phys. Chem., 1957, 61, 727.4, 344.1957,180, 1010, 1012ADDISON AND GREENWOOD : THE TRANSITION ELEMENTS. 139powder TcCl,, whereas with rhenium the pentachloride ReC1, is formed.360Quinquevalent rhenium has a strong tendency to disproportionate, andpreparative methods which employ oxidizing agents (e.g., F, or BrF,) areunsuccessful. The complex K[ReF,], which is very sensitive to traces ofmoisture, has been prepared by the action of potassium iodide on ReF, inliquid sulphur dioxide, iodine being released.361 A simple method for thepreparation of the hexachlororhenate(rv) complex K2[ReC16] involvesreduction of the per-rhenate with chromous chloride in concentrated hydro-chloric acid; K,[ReBr,] is prepared by the same method.362The Iron Group.-When a stream of nitrogen containing iodine vapouris passed over ferrous iodide at 500-560", the vapour phase then containsthe species FeI, (which is unstable in the solid state) and Fe,16.363 Equi-librium vapour pressures for the ferrous bromide-water system over thetemperature range 2 5 4 0 0 " represent hydrates of FeBr, with 1, 2, and4H,O; in the absence of oxygen no appreciable amounts of hydrogenbromide were observed in the vapour throughout this temperature range.364Ruthenium tetroxide in aqueous hydrofluoric acid can be reduced byhydrogen peroxide to the RuIV state.Evaporation of the resulting redsolution gives a black solid of composition [Ru(H,O) 50H]F,.365 An interest-ing aspect of the equilibrium RuIV +- RuIII concerns the complexK,[Ru(OH)CI,] ; treatment of this with reducing agents (e.g., TiC1,) givesK,[Ru(H,O)C~,].~~~ Nitrosyl-ruthenium chemistry has been further studiedand the compounds examined include (RuNO)(NO,),, 2 and 3H,O,(RuNO)(OAc),, Na[(RuNO)(OAc),], H,[(RuNO)(C,O,),] and its ammoniumand magnesium salts.367 Osmium forms an octavalent oxyfluoride Os0,F2by treatment of osmium metal sponge with an oxygen-fluorine mixture inthe volume ratio 2 : 1. It is an orange solid, melting at 170-172" to a redliquid, and is the parent of the trifluoroperosmates M[OsO,F,] (whereM = K, Cs, Ag).An oxychloride OsOCl, has also been prepared. Theseare the first true simple oxyhalides of osmium to be reported. Attempts toprepare the simple or complex oxyfluorides of ruthenium were un-successful.368The Cobalt Group.-Univalent cobalt has been obtained in the form of itsdipyridyl complex. The perchlorate [Co(dipy),] (C10,),,3H20, in suspensionin aqueous ethanol, was reduced with sodium borohydride. Evaporation(in an inert atmosphere) of the deep blue solution obtained gave dark bluecrystals of the compound [Co(dipy),]ClO,. It is slightly soluble in water,and is oxidized by oxygen to the [Co(dipy)J2+ i0n.~6~ The properties ofcobalt(Ir1) acetate differ from those of many simple cobaltic salts, which3130 K.Knox, S. Y. Tyree, jun., R. D. Srivastava, V. Norman, J. Y. Bassett, jun.,361 R. D. Peacock, J., 1957, 467.362 V. W. Meloche and R. Martin, J . Amev. Chem. SOC., 1956, 78, 6965.363 H. Schafer and W. J . Hones, Z . anorg. Chem., 1956, 288, 64.Y B 1 N. W. Gregory, J . Phys. Chem., 1957, 61, 369.ae5 M. L. Hair, M. A. Hepworth, and P. L. Robinson, J., 1957, 1927.3 B 6 N. K. Pshenitsyn and S. I. Ginzburg, Zhur. neorg. Khin~., 1957, 2, 112.367 0. Ye. Zvyagintsev and S. M. Starostin, ibid., p. 1281.36* M. A. Hepworth and P. L. Robinson, J . Inorg. Nuclear Chem., 1957, 4, 24.368 A. A. VICek, Nature, 1957, 180, 753.and J. H. Holloway, J . Amer. Chem. Soc., 1957, 79, 3358140 INORGANIC CHEMISTRY.decompose rapidly in water. It is stable at room temperature but de-composes at loo", evolving acetic acid.Solutions in acetic acid or ethylalcohol are stable, the oxidizing power remaining unchanged for long periods.In aqueous solution slow hydrolysis to cobaltic hydroxide occurs, but additionof dilute mineral acids causes rapid reduction to the cobaltous state.370The kinetics of this spontaneous reduction from cobalt (111) to cobalt(11) hasbeen examined with cobalt (111) perchlorate s0lutions.3~~ Very few examplesexist of cobalt(I1z) complexes having the phosphate group as ligand.Two such compounds have recently been prepared, the neutral[Co(NH3),P0,],2H,0 (in which the phosphate group is bidentate) and[Co(NH,),HP04],P0,. It is significant that attempts to prepare phosphato-pentamminocobalt (111) complexes were unsuccessful.372 The alkali-metalsalts M,[CoF,] are strongly paramagnetic (5.2 B.M.), whereas the ion[co(H20),l3' is diamagnetic.The magnetic moment of hydrated cobaltfluoride, CoF3,3.5H,0, represented as [CoF,,3H20],0.5H,0, is 4-47 B.M.This is regarded as indicating that when three of the F- ions in [CoF,I3- arereplaced by water molecules, the ligand field is still not sufficient to bringabout any appreciable degree of spin coupling, a result which is in contrastto that for the complex [COF,(NH,),].~~~A stable rhodium perchlorate, Rh(C10,),,6H20, has been prepared byreactbn of the trichloride with perchloric acid. It is crystalline and water-soluble. The six water molecules are probably co-ordinated to the rhodiumcation, and can be replaced by other ligand~.~'~ When iridium powder isheated with strontium oxide at 1200" in air, a double oxide Sr,IrO, is formed,isotypic with K,NiF,.No perovskite-type compound could be obtained inthis system.375The Nickel Group.-Consideration of the magnetic moments and re-flection spectra of a number of nickel(I1) (mainly triaminotriethylamino)complexes indicates that many which are apparently tetrahedral are in factoctahedral.376 Nickel@) complexes with 1 : 2-diethylthio- and 1 : 2-di-methylthio-ethane (which act as a chelate group by virtue of the twosulphur atoms) have been prepared. With nickel halides, dihalogeno-complexes (Ni[R*S*(CH,) ,*SR] 2Hal,} are formed, but nickel perchlorate givesthe tris-chelate (Ni[R~S*(CH,),*SR],}(C102)a.In all cases the nickel atom isoctahedrally b0nded.3'~ Several compounds of the type Ni(PX,), are al-ready known, but the first synthesis of such a compound by direct reactionwith metallic nickel is now reported. Methyldichlorophosphine was refluxedthrough a column of nickel turnings; on cooling, the compound Ni(MePCl,),crystallized. It is soluble in organic solvents, decomposes at 170" and isonly stable while protected from the atmosphere.378 The blue compoundNi(DH\,,2HCl (where DH, = dimethylglyoxime) formed by addition ofs70 J . A. Sharp, J., 1957, 2030.372 S. S. Daniel and J. E. Salmon, J., 1957, 4207.a75 H. C. Clark, B. Cox, and A. G. Sharpe, ibid., p. 4132.s74 G. H. Ayres and J. S. Forrester, J . Inorg. Nuclear Chem., 1957, 3, 365.375 J.J. Randall, jun,, L. Katz, and R. Ward, J. Amer. Ghem. SOL, 1957, 79, 266.376 R. W. Asmussen and 0. Bostrup, Acta Chem. Scand., 1957, 11, 1097.s77 R. Backhouse, M. E. Foss, and R. S. Nyholm, J.. 1957, 1714.378 L. D. Quin, J . Amer. Chem. SOC., 1957, 79, 3681.J . H. Baxendale and C. F. Wells, Trans. Favaday SOC., 1957, 53, 800ADDISON AN11 GREENWOOD: THE TRANSITION ELEMENTS. 141hydrogen chloride to the red nickel derivative Ni(DH) , has a magneticmoment (3.07 B.M.) compatible with either tetrahedral or octahedral con-figuration. However, its solution in acetone reacts only slowly with silvernitrate, and has a slight conductivity. It is probably an octahedral complex[Ni(DH,) ,Cl,] with two trans-chlorine atoms.The palladium complex[Pd( DH ,) Cl,] is not analogou~.~ 79 The bis-(N-me thylsalicylaldimine) -nickel(I1) complex is diamagnetic in the solid state, but paramagnetic insolution in benzene or chloroform. Although conversion from planar intoa tetrahedral configuration might account for this, solvent molecules mayco-ordinate to the metal and change its magnetic properties. Accordingly,measurements have been made on the complexes (from bis-N-ethyl tobis-N-decyl) in the molten state, and paramagnetism (O%--1-15 B.M.) isfound in the molten state as well as in solution.380 However, dipole momentsmeasured in benzene or chloroform solution do not support a tetrahedralstructure, and the paramagnetism has been explained in terms of anequilibrium involving outer-orbital sp2d planar config~ration.~*l Nickel(I1)bisacetylacetone, shown recently to be trimeric in the solid state, has beenstudied in the vapour by electron diffraction.The four oxygen atoms aresquare planar round each nickel atom, in spite of the paramagnetism of thecompound (3.2 B.M.).382Belucci’s salt K4[Ni2(CN)J reacted with sulphur nitride (N4S4) in alcoholicsolution to give a blood-red solution from which a stable orange complexwas isolated which appeared by analysis to be K[Ni(CN),(NS),]. However,its infrared spectrum indicated that an N-H bond was present in thecomplex; the anion therefore has structure (26) or its tautomeric forms, andHIN=S\ ,N-S,~i’ I I Nix INZC K S = N s-y’ S=N? NEC, N-SH( 2 6 ) ( 2 7 )the nickel atom is formally bivalent.3s3 In the interesting series of com-pounds M(NS), formed by N4S4 with transition metals, there has beendifficulty in envisaging satisfactory electronic structures for the two planarN2S, chelate groups.The problem is now modified by the observation(by analysis, spectroscopy, isotope exchange, and proton-spin resonance)that the nickel compound contains two hydrogen atoms, and is in factNiN4S4H2. Since this is formed from N,S, + NiC1, in ethanol, the hydrogenmust come from the solvent ; no product is obtained when carbon disulphideor benzene is used as solvent. The structure (27) may now represent thecompound, with nickel in the +Z oxidation state.384Further examination of the physical properties of the nickel cyanide-ammonia clathrate compound Ni(CN) $H,,C,H, has shown that, contraryL.Sacconi, R. Cini, and F. Maggio, J . Amw. Chem. Soc., 1957, 79, 3933.379 A. G. Sharpe and D. B. Wakefield, J., 1967, 496, 3323.381 L. Sacconi, P. Paoletti, and G. Del Re, ibid., p. 4062.882 S. Shibata, M. Kishita. and M. Kubo, Nature, 1957, 179, 320.383 J. Weiss, 2. Naturforsch., 1957, 12b, 481.a*4 T. S. Piper, Chem. and Ind., 1957, 1101; see also E. Fluck and M. Goehring,2. Natuvforsch., 1956, l l b , 756142 INORGANIC CHEMISTRY.to previous belief, benzene can be removed rapidly in vacuum at 40-60".X-Ray powder photographs taken during this process reveal progressivechanges in unit-cell dimensions, but no breakdown of the lattice.385 Nickelcyanide forms two ammines; with concentrated ammonia solution theunstable Ni(CN)2,4NH,,2H,0 is formed, which on exposure to air gives thepale blue, stable compound Ni(CN) 2,NH3,H20.386 The products of reactionof nickel with sodium hydroxide, in a vacuum and at temperatures nearlOOO", are numerous; they include hydrogen, water, sodium oxide, nickeloxide, sodium nickelate, and sodi~rn.~8'In the chloro-bridged dirneric complexes [L2Pd2C1,], where L is an amine,a tertiary organic phosphine, arsine, or stibine, or a dialkyl sulphide, selenide,or telluride, two well-graded series are found depending upon the positionof L in the Periodic Table. The reaction with monoamines (am)[L,Pd,CI,] + 2am Z[L,am,PdCI,]varies with the identity of L.The mononuclear complex can be isolatedonly when the donor atom in L is phosphorus or arsenic.When the donoris sulphur, selenium, or tellurium, the product disproportionates at roomtemperature :Z[L,am,PdCI,] L,PdCI, + am,PdCIand when L is an olefin, immediate decomposition O C C U T S . ~ ~ ~ A number ofcomplex compounds of null-valent palladium with phosphorus donors havebeen prepared. Starting with Pd(R*NC),, three types of complex have beenisolated: (R*NC)L,Pd, PdL,, and PdL,, where L = triarylphosphine or tri-aryl phosphite. Compounds of the last class, e.g., (Ph,P),Pd, are largelydissociated in benzene to give (Ph3P),Pd.389 Palladium difluoride has beenprepared in the pure state by reaction of palladium(I1) iodide with brominetrifluoride. This gives an addition product PdF,,BrF,, which when heatedto 220" at atmospheric pressure with selenium tetrafluoride leaves the paleviolet PdF2.390 Spectrophotometric studies 391 on nitrobenzene solutionscontaining [PdBr4l2- and Br- ions give evidence of the formation of unstablehexabromopalladate (11) ion [PdBr6l4-.The discovery of a new valency state of platinum in a simple compoundis of obvious importance.Platinum hexafluoride has been formed byreaction of fluorine vapour (300 mm. pressure) with a platinum filament,very close to which was a liquid-nitrogen cold finger. The major productwas the involatile PtF,, but a more volatile fraction of PtF, (1.4 g. from10 g. of platinum) collected on the cold finger. Solid platinum hexafluorideis dark red, m. p. 56.7", and its vapour resembles that of bromine. The solidis isostructural with OsF, and IrF,.3923s5 E.E. Aynsley, W. A. Campbell, and R. E. Dodd, Proc. Chem. Soc., 1957, 310.386 E. E. Aynsley and W. A. Campbell, J., 1957, 4137.38' D. M. Mathews and R. F. Kruth, I n d . Eng. Chem., 1957, 49, 55.388 J. Chatt and L. M. Venanzi, J., 1957, 2351, 2445.3s9 L. Malatesta and M. Angoletta, ibid., p. 1186.390 N. Bartlett and M. A. Hepworth, Chem. and Ind., 1956, 1425.301 C. M. Harris, S. E. Livingstone, and I. H. Reece, Austral. J . Chew., 1957, 9, 282.392 B. Weinstock, H. H. Claassen, and J. G. Malm, J . Amer. Chem. SOC., 1957,79,5832ADDISON AND GREENWOOD : THE TRANSITION ELEMENTS. 143By reduction of ethylenediamine complexes of platinum(I1) with potass-amide or potassium metal in liquid ammonia, a series of compounds has beenprepared in which the platinum atom is in the (+1) or the (0) valent state;eg., reduction of [Pt(en),]I, with two equivalents of potassium gives[Pt (en) 2]0.393 An X-ray examination of single crystals of the compound[Pt(NHJ4(CH,*CN),]C1, has revealed that the four NH, groups lie in a planeabout the Pt atom, while the trans-acetonitrile molecules appear to lieparallel to this plane.They are therefore not co-ordinated through thenitrogen atom lone electron pairs {as in [Pd(C,H,-CN) ,C12]) and x-bondingof the C-N group is probably involved, resembling that in the olefincomplexes.394 Interest in the structure of Wolffram’s red saltPt (C2H,*NH2),C1,,2H20 has been maintained because of the apparent ter-valency of the platinum atom.From polarized absorption spectra it appearsthat the true structure may be [Pt(Et*NH2),C12] [Pt(Et*NH,),]Cl4,4H2O.The deep colour is attributed to a band which is strongly polarized along theneedle axis, owing to the presence of infinite chains -Pt2+-Cl-Pt4+-Cl-Pt2+-C1-parallel to this axis.395 Improved synthetic routes have beenCI ’ v ‘PPr,(20, CN ( 2 9 )devised for the preparation of octahedral platinum complexes, such as[PtBrClI(py) (NO,) (NH,)] containing five or six different ligands. Use ismade of the trans-effect of the ligands c0ncerned.~96 The two isomers ofthe binuclear platinous complex (28) were believed to represent cis- andtrans-positions of the CN groups about the PtS,Pt ring.The discovery thatsilver thiocyanate consists of infinite chains 409 in which bonding occursthrough nitrogen atoms has led to re-examination of structure (28). Infraredspectra and X-ray analysis now show that the a-isomer has structure (29).The two isomers of the tetrathiocyanate (PPrJ2Pt,(SCN), may also be ofthisReduction of cis- or trans-(PEt,) ,PtCl, gives a remarkable volatile chloro-hydride of formula (PEt,),PtHCl, m. p. 82”. It is soluble in all organicsolvents, distils unchanged at 130”/0.01 mm., and is colourless and dia-magnetic. It is the first definite example of a transition-metal hydridewhich exists as discrete molecules, and without carbon as a ligand atom.398The Copper Group.-Copper metal reacts vigorously with a mixture ofliquid dinitrogen tetroxide and ethyl acetate, and the compoundCu(N0,) ,,N,04 crystallizes from solution.Heating of this at 85-100”s93 G. W. Watt, R. E. McCarley, and J. W. Dawes, Amer. Chem. SOC., 1957, 79, 5163.394 C. M. Hams and N. C. Stephenson, Chem. and Ind., 1957, 426.395 S. Yamada and R. Tsuchida, Bull. Chem. SOC. Japan, 1956, 29, 894.396 L. N. Essen and A. D. Gel’man, Proc. Acad. Sci. U.S.S.R., 1956, 108, 309;s97 J. Chatt, L. A. Duncanson, F. A. Hart, and P. G. Owston, Nature, 1958,181, 43.Zhur. neorg. Khim., 1956, 1, 2475.J. Chatt, L. A. Duncanson, and B. L. Shaw, Proc. Chenz. SOC., 1957, 343144 INORGANIC CHEMISTRY.leaves the anhydrous nitrate Cu(NO,),, which is blue. When this is heatedat ~ ~ - 2 0 0 " it sublimes, and copper nitrate is found to be monomeric inthe gaseous phase.These surprising properties indicate that the nitrategroup is capable of a type of bonding not hitherto realized.399 Cuprous,argentous, and aurous ions form complexes with (o-diethylphosphinophenyl) -diethylarsine; the cuprous and aurous complexes have configuration (30) ;I- -+they have additional interest in comparison with the analogous o-phenylene-bisdirnethylarsine complexes, since they should show cis-trans-isomerism ifthe metal has planar configuration, or optical activity in the case of tetra-hedral configuration. X-Ray analysis of the iodides shows them to havetetrahedral configuration, but in spite of this no resolution was p0ssible.~00The variation in magnetic susceptibility of the copper(I1) salts of C,, C,, C,,,C,,, and C,, fatty acids is anomalous in that antiferromagnetic rather thanCurie-Weiss characteristics are observed. It is concluded that the salts havebasically identical structures [CU,(R*CO,)~(H~O), or ,] involving a weakCu-Cu bond.401 Electron-diff raction measurements on bisacetylacetone-copper(I1) (by evaporation of the solid at 170") confirm that in the vapourthe chelate has a square planar configuration (Cu-0 distance 1.95 A), inagreement with X-ray investigation^.^^The analogoussilver and gold compounds have discrete linear complex ions [NC-M-CN]-,but in the copper compound spiral polymer chains [Cu(CN),]; are formed,as in (31).This is claimed to be the first time that the copper(1) atom hasThe cyanide KCu(CN), has an unusual crystal structure.been proved to be 3-co-ordinate. The [Cu(CN),]- units are held together bya Cu-N bond (compare the A g N bond in AgSCN 409), the length of which,2.05 A, is somewhat longer than the value expected for a Cu-N singlebond.*03 The infrared spectrum of cuprous chloride vapour is consistentwith the presence of a cyclic polymer as the principal and electrondiffraction indicates that this is a trimer (CuCl), in the form of a six-memberedaQQ C. C. Addison and B. J. Hathaway, Proc. Chem. SOC., 1957, 19.400 W. Cochran, F. A. Hart, and F. G. Xlann, J., 1957, 2816.401 R. L. Martin and H. Waterman, ibid., p. 2645.402 S. Shibata and K. Sone, Bull. Clteiiz. SOC. Japan, 1956, 20, 852.404 W. Klemperer, S. A. Rice, and R. S. Berry, J. Amer. Chem. SOC., 1957, 79, 1810.D. T. Cromer, J. Phys. Chem., 1957, 61, 1388ADDISON AND GREENWOOD : THE TRANSITION ELEMENTS. 145ring of alternate copper and chlorine atoms having a very large amplitude ofsymmetrical bending vibration. The Cu-C1 distance is 2.16 k 4 0 6 Onaddition of lithium bromide to alcoholic solutions of cupric perchlorate, newbands appear successively in the absorption spectrum; these are ascribed 406to the formation of the groups CuBr+, CuBr,, CuBr,-, CuBr,,-, CUB^,^-,and CUBr64-. Similar observations have been made upon ether solutions.The halides MBr, (M = Mn, Fe, Co, Cu, Cd) are insoluble in ether, butdissolve on addition of lithium bromide. The complexes identified includeLi6CUBr7 and Li,MBr4.407 The anodic oxidation of copper in a number ofaqueous electrolytes can be explained on the assumption that the primaryelectrode reaction is the formation of unipositive copper. In the presenceof ions (CN-, C1-, S,0,2-) which form stable complexes with copper(I), themetal enters solution solely in the +1 state. or C10,-as electrolyte, the valency number is higher than unity at 25", but falls tounity at higher temperatures.408The structural unit in crystalline silver thiocyanate is an endless zigzagchain [as shown in (32)] which results from the formation of a covalent bondfrom the silver atom to the nitrogen atom of another SCN On theother hand, ammonium silver dithiocyanate is built up from AgSCNmolecules and NH4+ and SCN- ions; [Ag(SCN),]- ions are not formed, andthe chain structure of silver thiocyanate has been lost by addition ofNH4SCN.410 The infrared spectra of the compounds KAg(CN), andI(Au(CN), have been compared with those for the 13C- and 15N-substitutedspecies, and it is confirmed that the cyanide groups are bonded to the metalthrough carbon atoms, i.e., [N-C-AgC-N]-.4U The relative tendencies ofa series of similar (sulphonated) organic derivatives of the two groupsnitrogen, phosphorus, arsenic, and oxygen, sulphur, selenium to formcomplexes with silver ions have been compared. Silver forms the moststable complexes with the heavier donor atoms of each The hydro-lysis of sodium aurate has been examined from the variation in conductivity,diffusion, and light-absorption with change in pH. Only the monomericform of the anion (Au02,aq.)- was observed, and there was no evidence ofpolyacid formation.413It can be melted underas little as 50 lb./sq. in. of argon, rather than the 100-150 atm. pressurepreviously considered necessary. The m. p. of cadmium sulphide, at 150lb./sq. in. of argon, is 1475°.413 Tracer techniques have been employed tostudy the disproportionation reaction HgZ2+ =+= Hg2+ + Hg(aq.) in verydilute ( 10-T~) mercurous nitrate solution. The equilibrium constant isWith NO,-,The Zinc Group.-Zinc sulphide has m. p. 1830'.405 Chi-Hsiang Wong and V. Schomaker, J . Phys. Chem., 1957, 61, 358.406 E. M. Kosower, R. L. Martin, and V. W. Meloche, J . Anzer. Chem. SOL., 1957,*07 G. Monnier, Ann. Chim. (France), 1957, 2, 14.408 D. J. Royer, J. Kleinberg, and A. W, Davidson, J . Inorg. Nuclear Chew., 1957,409 I. Lindqvist, Acta Cryst., 1957. 10, 29.410 I. Lindqvist and B. Strandberg, ibid., p. 173.411 L. H. Jones, J . Chem. Phys., 1957, 26, 1578; 27, 468.412 S. Ahrland, J. Chatt, N. R. Davies, and A. A. Williams, Nature, 1957, 179, 1187.*13 G. Jander and G. Krien, 2. anorg. Chem., 1957, 291, 89.79, 1509.4, 115146 INORGANIC CHEMISTRY5.5 x The concentration of free mercury was estimated by extractioninto non-polar organic solvents. The solubility of mercury metal in wateris 3 x 10-7 mole/litre at 25". No evidence was found for the presence ofthe ion Hg+.415 The kinetics of reaction between mercurous and thallicsalts are also in agreement with this disprop~rtionation.~~~ The ,03Hgisotope has been used in the determination of formation constants of Hg1,-and HgI,2- by extraction of mercuric iodide into benzene.417 The cyanidegroups in the molecule Hg(CN), are bonded to the metal through carbonatoms,418 as in the argentous and aurous cyanide c o m p l e ~ e s . ~ ~ Hexagonalmercuric oxide contains infinite spiral chains -0-Hg-O-Hg, and is thusisostructural with the hexagonal form of mercuric ~ u l p h i d e . ~ ~ ~ A study ofthe reaction of the hydroxide ion with mercuric nitrate, the l80 isotopebeing used, has revealed that the initial step is the formation of the basicnitrate Hg,02(N0,),,H,0. In the presence of excess of mercuric nitratethis can be isolated, but with excess of hydroxide it is rapidly hydrolysed toHgO. The oxygen of the HgO so formed is derived from the water whicheffects the hydrolysis.420 By the reaction.3Hg0 + HgXz + 2RNHSX + [Hg,(NR),]X,HgXS + 3HZOa series of mercury iminohalides have been prepared in which X = C1 or Br,and R = H, C,H,, OEt, C,H,, or CO*NH2.421 The action of ammonia onmercury halides is known to give addition compounds [Hg(NH,) ,]X2, andtheir derivatives Hg*NH,X, where X = C1, Br, or I. The correspondinghydrazine compound [Hg(N,H,) ,]Cl, has been shown, from its infraredspectrum, to contain the ion [NH,*NH,*Hg*NH2*NH2l2 f-, analogous to thediammine. The mono-addition compounds [Hg(N,H,)]X, (X = C1, Br)contain the infinite chain -Hg-NH ,-NH ,-HgNH ,-NH ,-. The substitutioncompound [Hg,N,H,]Cl, has a layer lattice.422C. C. ADDISON.N. N. GREENWOOD.414 A. Addamiano and P. A. Dell, J . Phys. Chem., 1957, 61, 1020, 1253.416 H. C. Moser and A. F. Voigt, J . Amer. Chem. SOC., 1957, 79, 1837.416 A. M. Armstrong, J. Halpern, and W. C. E. Higginson, J . Phys. Chem., 1956,417 H. C. Moser and A. F. Voigt, J . Inorg. Nuclear Chem., 1957, 4, 354.418 L. H. Jones, J . Chem. Phys., 1957, 27, 665.419 K. Aurivillius and I. B. Carlsson, Acta Che,m. Scand., 1957, 11, 1069.420 R. B. Bernstein, H. G. Pars, and D. C. Blumenthal, J . Amer. Chenz. Soc., 1957,421 A. Meuwsen and G. Weiss, 2. anorg. Chem., 1957, 289, 5.422 K. Brodersen, ibid., 290, 24.60, 1661.79, 1579

ISSN:0365-6217    

DOI:10.1039/AR9575400093

出版商:RSC    

年代:1957

数据来源: RSC

摘要:

ORGANIC CHEMISTRY.1. INTRODUCTION.Tms Report begins with a review of developments in theoretical organicchemistry. In this field, important studies of heats of hydrogenation ofcyclic molecules have advanced knowledge of the contributions of conjug-ation, hyperconjugation, and steric strain in such systems. Notable develop-ments in understanding of the detailed reaction paths of multi-stage reactionshave occurred during recent years through examination of isotope effects onrates and products of reaction, and by correlation of reactivities with acidityfunctions appropriate to various types of ionisation ; numerous exampleshave been noted in the present Report, which focuses particular attentionon aromatic substitution and on nucleophilic displacements at a saturatedcarbon atom, since these subjects were not discussed last year.Conformational analysis receives special attention in the Report onstereochemistry. Notable advances have been made in the aliphatic fieldby tracer studies which indicate the mode of incorporation of mevalonic acidinto a number of natural products related to squalene.Mechanistic studiesof the effects of neighbouring aryl groups in nucleophilic displacements haveled to the isolation of some interesting spiro-dienones.Successful syntheses of note include those of penicillin V, pentacyclo-squalene, and onocerin derivatives. In the terpene field sesquiterpenescontinue to attract attention. The products resulting from irradiation ofap-unsaturated ketones and cross-conjugated dienones are being intensivelystudied and often have unusual structures.Other intriguing compoundsare 1 : 2 : 3-triphenylcyclopropenyl fluoroborate and the macrocyclic poly-acetylene resulting from the trimerisation of o-diethynylbenzene.Much progress has been made in establishing the sequence of amino-acids in enzymes, particularly for ribonuclease. The Report of carbo-hydrates focuses attention on mechanistic and conformational aspects ofmono- and di-saccharide chemistry. Oligo- and poly-saccharides as well asnucleic acids will be discussed next year. -r. G. H.P. R. D. DE LA M.2. THEORETICAL ORGANIC CHEMISTRY.SEVERAL recent review articles and books are of considerable value to thoseinterested in the mechanisms of organic reactions.Steric effects in organicchemistry have been surveyed.l Leffler has discussed the properties andmethods of identification of transient intermediates in chemical reactions.Paul and Long’s reviews clarify consideration of the applicability of theHammett and related acidity functions to chemical problems.“ Steric Effects in Organic Chemistry,” ed. M. S. Newman, Wiley, New York,J. E. Leffler, “ The Reactive Intermediates of Organic Chemistry,” Intersciencea M. A. Paul and F, A, Long, Chem. Rev., 1957, 57, 1; F. A. Long and M. A. Paul,1956.Publ. Inc., New York, 1956.ibid., p. 93514s ORGANIC CHEMISTHY.Applications of Spectroscopy.-Equilibria of the types :Py + ICI * PyICI; 2PylCI * Py,l+- + ICI,--have been studied spectrophotometrically in carbon tetrachloride and aceto-nitrile as solvents.* Examination of equilibria of the benzoquinolines withbromine provides evidence for the existence of charge-transfer complexes inthese systems, as also in the related complexes with sodium.5 The lessfirmly bound complexes between aromatic compounds and halogens havebeen investigated in two ways: (a) through their infrared spectra; theobservations have been interpreted as indicating that these complexes havec 6 V axial symmetry,6 wherein the halogen axis is coincident with the benzeneC, axis; and (b) through their ultraviolet spectra; 7 a general theoreticaldiscussion of these and related systems is available.* Such complexes areimportant in that they may be involved in many chemical reactions ofhalogens with olefinic and aromatic compounds, such as the iodine-catalyseddimerisation of 1 : l-diphenylethylene.gThe degree of conjugation between the nuclei in derivatives of diphenyldepends partly on the magnitude of steric interactions between atoms andgroups in the 2 : 2'-positions.Careful spectroscopic investi-~ c ~ r k - ~ r gations show, however, that electronic effects are often so im-portant that spectral measurements do not always give a reliableestimate of the angle between the planes of the aromatic rings.1°The spectra of aromatic sulphides, sulphoxides, and related compoundshave been discussed,ll particularly with reference to conjugation betweensulphur and adjacent unsaturated groupings by way of expansion of theoctet of the sulphur atom.It was concluded, for example, that conjugationas indicated in formula (I) does not contribute significantly to the structureof such compounds as p-Me,N°C,H,*S*C6H,*No2-~.Stereochemical Effects on Mesomerism.-The ultraviolet spectra of nitro-substituted aromatic carbonyl compounds l2 give evidence for steric in-hibition of mesomerism by ortho-substituents. The dipole moments,partidarly of substituted nitro-compounds, also provide additional evidencefor this type of modification of conjugation.l39 l4 Comparison of ultravioletand infrared absorption spectra, molecular refraction, basic strength, andreactivities of derivatives of nitrobenzene and aniline all show deviationsFormylferrocene has been obtained by treatment of ferrocene with N -methylformanilide and phosphorus oxychloride,ll0* u and from ferrocenyl-methyltrimethylammonium iodide by treatment with hexamine 112 or byhydrolysis to ferrocenylmethanol followed by oxidation with manganesed i 0 ~ i d e .l ~ ~ While it shows many normal aldehyde reactions, fonnylferroceneis surprisingly basic and has not yet been successfully oxidised to thecarboxylic acid. The substance obtained by rearrangement of ferrocenyl-methyltrimethylammonium iodide by treatment with potassamide is now 11*assigned the structure (65). Ferrocenylmethanols have an unusually labilehydroxyl group ; thus a-ferrocenylbenzyl alcohol is converted into themethyl ether in boiling methan01.l~~ Cyclisation of p-ferrocenylpropionic101 K. L. Rinehart and K.L. Motz, Chem. and Ind., 1957, 1150.102 R. E. Benson and R. V. Lindsey, J. Amer. Chem. SOL, 1957, 79, 5471.108 D. S. Trifan and L. Nicholas, ibid., p. 2746.104 A. N. Nesmeyanov, Doklady Akad. Nauk S.S.S.R., 1957, 112, 439.lo6 M. Rausch, M. Vogel, and H. Kosenberg, J. Org. Chem., 1957, 22, 900.106 D. W. Mayo, P. D. Shaw, and M. Rausch, Chem. and Ind., 1957, 1388.107 M. Vogel, M. Rausch, and H. Rosenberg, J. Org. Chem., 1967, 22, 1016.108 A. N. Nesmeyanov and N. S. Kotchetkova, Duklady Akad. Nauk S.S.S.R.,lo9 K. L. Rinehart, K. L. Motz, and S. Moon, J. Amer. Chem. SOL, 1957, 79, 2749.111 P. J. Graham, R. V. Lindsey, G. W. Parshall, M. L. Peterson and G. M. Whit-112 G. D. Broadhead, J . M. Osgerby, and L. R. Pauson, Chem. and Ind., 1957, 209.l13 J.K. Lindsay and C. R. Hauser, J . Org. Chem., 1957, 22, 355.114 C. R. Hauser, J . K. Lindsay, D. Lednicer, and C. E. Cain, ibid., p. 717.116 N. Welicky and E. S. Gould, J. Amer. Chem. SOC., 1957, 79, 2742; M. Rausch,1956,109, 543.M. Rosenblum, Chem. and Ind., 1957, 72.man, J. Amer. Chem. SOC., 1957, 79, 3416.M. Vogel, and H. Rosenberg, J. Org. Chem., 1957, 22, 903SCHOFIELD HETEROCYCLIC COMPOUNDS. 239acid (66; n = 2) gives the bridged ketone (67), whereas y-ferrocenylbutyricacid (66; n = 3) and 6-ferrocenylvaleric acid (66; n = 4) undergo homo-annular cyclisation 116 to ketones of type (68). Ferrocenyl-substituteda-amino-acids have also been prepared.l17“ Sandwich ” structures have been obtained in which a metal atom islinked to both a cyclopentadiene ring and a benzene ring; e.g., the action ofphenylmagnesium bromide on methylcycZopentadienylmanganese chloride orbismet hylcyclopent adien ylmanganese gives the complex MeC,H,*Mn , C6H6 .llThe benzene-diphenylchromium cation , [C6H6-Cr(C6H,*C6H,)] +, is formed inthe reaction of phenylmagnesium bromide with chromium chloride or by thereductive Friedel-Crafts synthesis from a mixture of benzene and di~henyl.1~~Pyrolysis of the mercuri-iodide affords benzene and diphenyl in practicallyquantitative yield.120 The stability of the iron complexes of methylbenzenesincreases with the number of methyl groups attached to the benzene ring.121Attempts to apply typical aromatic substitution reactions to dibenzene-chromium(0) led to disruption of the molecule.122R.F. G.8. HETEROCYCLIC COMPOUNDS.MONOGRAPHS on polyazines and phenazines,l and two further volumes ofElderfield’s series have appeared. p - l a ~ t a m s , ~ phenanthridine~,~ hetero-aromatic N-oxides,h and meso-ionic compounds 46 have been reviewed.116 K. L. Rinehart and R. J. Curby, J . Amer. Chem. SOC., 1957, 79, 3290; K. L.Rinehart, R. J. Curby, and P. E. Sokol, ibid., p. 3420.117 K. Schlogl, Monatsh., 1957, 88, 601; C. R. Hauser and J. K. Lindsay, J . Org.Clzem, 1957, 22, 1246.118 T. H. Coffield, V. Sandel, and R. D. Closson, J . Amer. Chem. SOC., 1957, 79,5826.lls F. Hein and H. Muller, Chem. Ber., 1956, 89, 2722; F. Hein and K. Eisfeld, 2.anorg. Chem., 1957, 292, 162; F. Hein, P. Kleinert, and E.Kurras, ibid., 1957, 289,229; H. H. Zeiss and M. Tsutsui, J , Amer. Chem. SOC., 1957, 79, 3062.120 F. Hein and E. Kurras, 2. anorg. Chem., 1957, 290, 179.121 M. Tsutsui and H. H. Zeiss, Naturwiss., 1957, 44, 421.lZ2 H. P. Fritz and E. 0. Fischer, 2. Naturforsclz., 1957, 12b, 67.J. G. Erickson, P. F. Wiley, and V. P. Wystrach, “The Chemistry of Hetero-cyclic Compounds. Vol. 10. The 1 : 2 : 3- and 1 : 2 : 4-Triazines, Tetrazines, andPentazines,” Interscience Publ. Inc., New York, 1957, and “ Vol. 11. The Phenazines,”by G. A. Swan and D. G. I. Felton, in the same series.R. C. Elderfield (editor), “ Heterocyclic Compounds. Vol. 5. Five-MemberedHeterocycles Containing Two Hetero Atoms, and Their Benzo Derivatives,” and “ Vol.6. Six-Membered Heterocycles Containing Two Hetero Atoms, and Their BenzoDerivatives,” John Wiley and Sons, Inc., New York, 1957.Vol.IX,” p. 388, JohnWiley and Sons, Inc., New York, 1957.3 J. C. Sheehan, and E. J. Corey, “ Organic Reactions.4 J. Eisch and H. Gilman, Clzem. Rev., 1957, 57, 525.40 A. R. Katritzky, Quart. Rev., 1956, 10, 395.W. Baker and W. D. Ollis, ibid., 1957, 11, 15240 ORGANIC CHEMISTRY.Small Rings.-Alkaline hydrogen peroxide converts a-methylstyreneepoxide into acetophenone.6 Five- and six-membered cyclic ethers form1 : l-complexes with boron trichloride, whilst three- and four-memberedcompounds are cleaved to (chloroa1koxy)boron esters.6 Hydride reduction 7of oxetans (derivatives of 1) having two or fewer alkyl groups causescleavage between the oxygen and the less substituted carbon atom.3 : 3’-Bischloromethyloxetan with sodium sulphide gives the spiran (2) whichforms a sulphone.8More oxazirans (3) have been prepared,1° and a comprehensive accountof their properties has been given.ll Proof of structure depends onhydrolysis to aldehydes and N-alkylhydroxylamines, comparison with,and isomerisation to, nitrones, and resolution of 3-isobutyl-3-methyl-2-propyloxaziran.Ketens with azomethines have given a variety of @-lactams.12Five-membered Rings-Pyrroles. N-Substituted pyrroles result fromthe action of primary amines upon 1 : 4-bisdimethylaminobuta-1 : 3-diene,13ora’-dibromoadiponitrile,14 and 1 : 2 : 3 : 4-tetrabromob~tane.1~ Methyl-pyrroles can be prepared by reduction of pyrrole Mannich bases.16 Avariation of the Knorr pyrrole synthesis consists in the reduction of phenyl-azo-derivatives of p-dicarbonyl c0mpounds.1~ Porphobilinogen (4 ; R =CH,*NH,, R’ = H) has been synthesised by several methods 18 from thealdehydo-ester (diethyl ester of 4; R = CHO, R’ = C0,Et).Tripyrryl-methenes are readily obtained from pyrrolecarboxylk acids (or their tert.-butyl esters) and pyrroles in the presence of phosphoryl ch10ride.l~Treibs and his co-workers have demonstrated the basic properties ofmany pyrrole derivatives, and, contrary to current views, stress the impor-tance of these properties in influencing reactions in this series.20 In theC-acylation of N-methylpyrrole by ethylmagnesium bromide and acylJ. Hoffman, J . Amer.Chern. SOC., 1957, 79, 503.6 J. D. Edwards, W. Gerrard, and M. F. Lappert, J., 1957, 348.7 S. Searles, jun., K. A. Pollart, and E. F. Lutz, J . Amer. Chem. SOL, 1957, 79,* T. W. Campbell, J . Ovg. Chem., 1957, 22, 1029.0 Cf. Ann. Reports, 1956, 53, 229; Farbenfabriken Bayer, B.P. 743,940/1953 and948; S. Searles, jun., K. A. Pollart, and F. Block, ibid.. p. 952.other patents.10 L. Homer and E. Jurgens, Chem. Ber., 1957, 90, 2184.11 W. D. Emmops, J . Amer. Chem. SOL, 1957, 79, 5739.12 (a) W. Kirmse and L. Homer, Chem. Ber., 1956, 89, 2759; (b) R. Pfleger and A.13 M. F. Fegley, R. M. Bortnick, and C. H. McKeever, J . Amer. Chem. SOC., 195714 A. Treibs and F. Neumayr, Chem. Ber., 1957, 90, 76.16 A. Treibs and 0. Hitzler, ibid., p. 787.l6 A.Treibs and R. Zinsmeister, ibid., p- 87.17 A. Treibs, R. Schmidt, and R. Zinsmeister, ibid., p. 79.18 A. H. Jackson and S. F. MacDonald, Canad. J. Chem., 1957, 35, 715.1s A. Treibs and K. Hintermeier, Annulen, 1957, 605, 35.20 A. Treibs and H. G. Kolm, ibid., 1957, 606, 166; A. Treibs, E. Herrmann, E.Jager, ibid., 1957, 90, 2460.79, 4144.Meissner, and A. Kuhn, ibid., 1957, 60% 163SCHOFIELD : HETEROCYCLIC COMPOUNDS. 241chlorides, probably a Friedel-Crafts type reaction, ethylmagnesium bromidecan be replaced by magnesium bromide.21 Nitration of pyrrole gives 3-as well as 2-nitr0pyrrole,~~ and rather unexpectedly thiocyanation of pyrrolegives 3-thiocyanopyrrole.23Pyrrole trimer is proved to have structure (5) by degradation to 1 : 4-di-2 '-pyrrolylbutane .24 Netropsin (antibiotic T-1384, congocidine) is assignedMethe structure [6; R = C(:NH)*CH,*NH*C(:NH)*NH,J ; the chief products ofalkaline hydrolysis [6; R = H; and R = CO*CH2*NWC(:NH)-NH2] havebeen synthe~ised.~~Mild reduction of 4 : 4-dimethyl-5-nitropentan-%one gives 2 : 4 : 4-trimethyl-Al-pyrroline l-oxide (7). This and 4 : 5 : 5-trimethyl-Al-pyrrolinel-oxide 26 are the first non-aromatic monomeric nitrones.The 2-methylgroup in compound (7) undergoes base-catalysed condensation with aromaticaldehydes. Pyrrolid-3-one and 3-hydroxypyrrolidine have been preparedfrom l-ethoxycarbonylpyrrolid-3-0ne.~~Fzcrans. Adducts (8) from acetoacetic ester and a-nitro-olefins givefurans in the Nef reaction.28 Furans with free a-positions are readilyformylated by dimethylformamide and phosphoryl ch10ride.~~ Perillaketone has been synthesised from diisopentylcadmium and furan-l-carbonylchloride.30 The compound formed from pyruvic acid and benzylidene-aniline, previously taken to be a dioxopyrrolidine, has been re-formulated 31The reaction between furfuryl alcohol and methanolic hydrogen chloridegives, not 8-, but or-methoxylzvulaldehyde dimethyl a ~ e t a l .~ ~ Conversionof 5-aminomethylfurfuryl alcohol into 5-hydroxy-2-methyIpyridine byacid, and related reactions, have been reported.33(9).21 W. Herz, J. Org. Chem., 1957, 22, 1260.22 €3. j. Anderson, Canad. J. Chem., 1957, 35, 21.28 D. S. Matteson and H. R. Snyder, J. Org. Ghem., 1957, 22, 1500; J. Amer. Chew.SOL, 1957, 79, 3610.24 H.A. Potts and G. F. Smith, J., 1957, 4018.25 C. W. Waller, C. F. Wolf, W. 3. Stein, and B. L. Hutchings, J . Amer. Chem. SOC.,1957, 79, 1265; M. J. Weiss, J. S. Webb, and J. M. Smith, jun., ibid., p. 1266; seealso E. E. van Tamelen and A. D. G. Powell, Chem. and Ind., 1957, 365.26 R. F. C. Brown, V. M. Clark, and Sir Alexander Todd, Proc. Chem. Soc., 1957, 97.27 R. Kuhn and G. Osswald, Angew. Chem., 1957, 69, 60.28 F. Boberg and G. R. Schultze, Chem. Ber., 1957, 90, 1215.29 V. J. Traynelis, J. 3 . Miskel, jun., and J. R. Sowa, J. Org. Chew., 1957, 22, 1269.30 T. Matsuura, Bull. Chem. SOC. Japan, 1957, 30, 430.31 H. H. Wasserman and R. C. Koch, Chem. and Ind., 1957, 428.82 K. G. Lewis, J., 1957, 531; L. Birkofer and R.Dutz, Annaleua, 1957, 608, 7 .88 N. Elming and N. Clauson-Kaas, Acta Chem. Scand., 1956,10, 1603; N. Elming,ibid., p. 1664242 ORGANIC CHEMISTRY.Thiophens. Re-investigation of the oxidation of 3-thienylmagnesiumbromide disclosed a small yield of the unstable 3-hydroxythiophen which,unlike the 2-isomer, is appreciably phenolic. Hofmann decomposition of3-dimet hylaminomet hyl-4-methylenethiophan gave 3 : 4-dimethylthiophenrather than 3 : 4-dirnethylenethio~han.~~(10) ( I I) (12)Azoles. Details of an earlier synthesis of cycloserine (10) have beengiven and other new syntheses, one based on methyl N-triphenylmethyl-aziridine-2-carboxylate, are reported.36 Dichloroglyoxime with acetylenicGrignard reagents gives 3 : 3‘-diisoo~azolyl.~~ 4-Chloromethylene-2-phenyl-oxazol-&one reacts with organometallic reagents to give azla~tones.~~Oxazol-%ones, with organometallic reagents (e.g., R4MgBr) form ct-acyl-amino-ketones which are converted by strong acids into oxazoliumsalts 39 (1 1).A3-Thiazolines can be obtained from ketones by means of ammonia andsulphur, or from ammonia and ct-mercapto-ketones.With acetone theyield is poor and some dihydro-2 : 2 : 4 : 6 : 6-pentamethyl-1 : 3-thiazineis formed (see below). A3-Thiazolines with hydrogen atoms at andR-C -CR‘s-sare readily dehydrogenated to thia~oles.~~ Acid anhydrides (R’CO) 2Oconvert N-thiobenzoylsarcosine and N-ethyl-N-thiobenzoylglycine intomesoionic compounds (12; R = Me and Et respectively).*l 2 : 2’-Thia-zoloin exists as the orange e n e - d i ~ l .~ ~Degradation of bottromycin has provided the new amino-acid p-2-thia~olyl-p-alanine.~~ Among the products of acid degradation of another34 M. C . Ford and D. Mackay, J., 1956, 4985.35 C. S. Marvel, R. M. Nowak, and J. Economy, J . Awzer. Chem. SOL., 1956, 78,6171.86 Ann. Reeorts, 1955, 52, 232; C. H. Stammer, A. N. Wilson, C. F. Spencer,F. W. Bachelor, F. W. Holly, and K. Folkers, J . Amer. Chem. SOL, 1957, 79, 3236;J. Smrt, J. Beranek, J. Sicher, and F. Sorm, CoZZ. Czech. Chem. Comm., 1957, 22, 262;P. A. Plattner, A. Boller, H. Frick, A. Fiirst, B. Hegediis, H. Kirchensteiner, St.Majnoni, R. Schlapfer, and H. Spiegelberg, HeZv. Chim. Acta, 1957, 40, 1531.37 A. Quilico, G. Gaudiano, and A. Ricca, Gazzetta, 1957, 87, 638.38 H.Behringer and H. Taul, Chem. Ber., 1957, 90, 1398.39 R. Gompper, ibid., p. 374.40 F. Asinger, M. Thiel, and E. Pallas, AnnuZen, 1957, 602, 37; M. Thiel and F.Asinger, ibid., 1957, 610, 17; F. Asinger, M. Thiel, and I. Kalzendorf, ibid., p. 25;F. Asinger, M. Thiel, and G. Esser, ibid., p. 33; F. Asinger, M. Thiel, and L. Schroder,ibid., p. 49.41 A. Lawson and C . E. Searle, J., 1957, 1556.42 H. Beyerand U. Hess, Chem. Ber., 1957, 90, 2435.43 J. M. Waisvisz, M. G. van der Hoeven, and B. Te Nijenhuis, J . Amer. Chem.SOC., 1957, 79, 4524SCHOFIELD : HETEROCYCLIC COMPOUNDS. 243antibiotic, micrococcin P, are Z-propionyl- and (+)-2-( l-amino-Z-methyl-propyl)-thiazole-4-carboxylic acid, and a complex polythiazole, which areconsidered to arise from the incorporation of cysteine and other amino-acids in a peptide chain.44Bases convert arylsulphonylhydrazones of type (A) into pyra~oles.~~( A ) R*CH:CH*CN:N*NH*SO,*Ar (B) Ph*CH2*CH,*O*CO*CH,*NH*CH:NHn-Butyl-lithium metalates 4g N-substituted glyoxalines at position 2.Liberated from its hydrochloride, N- (phene t hylox ycarbonylme t hyl) amidine(B) cyclises to the highly reactive 4 : 5-dihydro-5-oxoglyoxaline (13) which isprobably an intermediate in the enzymic degradation of ~anthine.~’ 4-Nitro- and 4-amino-5-glyoxalinyl-sulphones , and 4-amino-1 : 2 : 3-triazole-5-carboxyamide, have been synthesised 48 as possible antagonists of the inter-mediate in purine biosynthesis, 4-aminoglyoxaline-5-carboxyamide.Thesuggestion that the glyoxaline nucleus of histidine is important in the activityof hydrolytic enzymes is supported by the peculiar effectiveness of glyoxalineas a catalyst of ester hydroly~is.~~ The urea, NN’-carbonyldiglyoxaline(14), and its triazole analogue are highly reactive, giving carbonic esterswith alcohols and phenols, and ureas with amines.jOOther systems.With nitrous fumes, P-methyl-a-methylaminobutyro-nitrile and y-methyl-a-methylaminovaleronitrile give sydnone iminenitrates (nitrates of 15; R = Pri or But, R’ = -NH). Acetic anhydridedehydrates the nitrates to nitro-imines (15; R’ = --N*N0,).51New syntheses of thioctic acid (16; 92 = 4) start from ethyl 6-oxo-oct-7-enoate and 2-acetoxymethylcycZohexanone. 52 Homologues (16 ; n = 3and 5) and analogues (16; n = 4, *SO,*NH, in place of *CO,H) have alsobeen synthesised as possible metabolite antagonist^.^^Six-membered Rings.-2 : 4 : 6-Triphenylpyryliurn fluoroborate givesl-nitro-2 : 4 : 6-triphenylbenzene with sodio-nitromethane, a reaction of somegenerality.5p a- and y-Pyrones, and their hydroxy-derivatives and sulphur an-alogues, can to some extent be regarded as pseudo-tropones and -tropolones. 55Ethylene glycol, butadiene, and a mercuric salt give cis- and trans-2 : 3-disubstituted dioxans (17) .56Pyridines and piperidines. Adducts (1 8) from a-carbonylacetylenesand enamines cyclise, when heated, to 2 : 3 : 6-trisubstituted pyridines.5744 P. Brookes, A. T. Fuller, and J. Walker, J., 1957, 689.45 A. Dornow and W. Bartsch, Annalen, 1957, 602, 23.46 D.A. Shirley and P. W. Alley, J . Amer. Chem. SOC., 1957, 79, 4922.47 K. Freter, J. C . Rabinowitz, and B. Witkop, Annalen, 1957, 607, 174.48 L. L. Bennett, jun., and H. T. Baker, J . Amer. Chem. SOL, 1957, 79, 2188; J .Org. Chem., 1957, 22, 707.40 M. L. Bender and B. W. Turnquest, J . Auner. Chem. SOC., 1957, 79, 1652; T. C.Bruice and G. L. Schmir, ibid., p. 1663; W. Langbeck and R. Mahrwald, Chem. Ber.,1957, 90, 2423.5 0 H. A. Staab, Annalen, 1957, 609, 75.51 P. Brookesand J. Walker, J., 1957, 4409.62 M. W. Bullock, J. J. Hand, and E. L. R. Stokstad, J . Amer. Chem. SOC., 1957,53 R. C. Thomas and L. J. Reed, ibid., 1956, 78, 6150, 6151.54 K. Dimroth, G. Brauninger, and G. Neubauer, Chem. Bey., 1957, 90, 1634;5 5 R.Mayer, Chem. Ber., 1957, 90, 2362.56 R. K. Summerbell and G. J. Lestina, J . Amer. Chem. SOC., 1957, 79, 3878.5 7 F. Bohlmann and D. Rahtz, Chem. Ber., 1957, 90, 2265.79, 1978; A. Segre, R. Viterbo, and G. Parisi, ibid., p. 3503.K. Dimroth, G. Neubauer, H. Mollenlramp, and G. Oosterloo, ibid., p. 1668244 ORGANIC CHEMISTRY.2-Pyridones are formed from 13-keto-nitriks, or from amides and ketones(and thus by hydrolysis of a-acylbenzyl cyanides),5s and also ham l-(carb-amoylmethy1)pyridinium chloride and Mannich bases (eg., 19 -20).6s(21)Me (22; R=H)3 : 5-Lutidine is conveniently synthesised from diethyl acetonedicarboxy-late.60 Hydrogen is evolved when sodium dissolves in pyridine, a factpreviously overlooked ; sodium pyridyls are presumably forrned.61 Criticalexamination of the Emmert-Asendorf reaction (co-reduction of pyridineand carbonyl compounds to pyridylcarbinols) led to the observation that,in the presence of aluminium or magnesium, esters can acylate pyridinedirectly.Acid anhydrides are not effective, but NN-dimethylbenzamidegives 2- (50%) and 4-benzoylpyridine (4%) .62 3- and 5-Amino-2-hydroxy-pyridines can be oxidised to hydroxyazaquinones (21) .633-Hydroxypicolinic acid occurs in the polypeptide antibiotic etamycin.B4The structure (22; R = Me) for muscopyridine (from the perfume glandof the musk deer), derived from biogenetic arguments, has been confirmed 65by the ingenious synthesis outlined in the formulae.Dipole-moment studies show that the oxide function in pyridine 1-oxidescan create a surfeit or a deficiency of electrons at position 4; the base-strengths and spectroscopic characteristic of 2- and 4-aminopyridine 1-oxidesshow them to exist in the m i n e forms, whereas the 4-hydroxy-compoundis a mixture of comparable amounts of both possible tautomers.66 %Nitro-pyridine l-oxides are formed by oxidation of the 2-amino-compounds.675 * J.F. M. Wajonand J. F. k e n s , Rec. Trav. chiwt., 1957, 76, 65, 79; C. R. Hauserand C. J. Eby, J . Amer. Chem. SOL, 1967, 79, 728.60 E. A. CouIson and J. €3. Ditcham, J., 1957, 356.6a G. B. Bachman, M. Hamer, E. Dunning, and K. M. Schisla, J . Org. Chem., 1957,64 J. C. Sheehan, H. G. Zachau, and W. B. Lawson, ibid., p. 3933.66 A. R. Katritzky, J., 1957, 191; A.R. Katritzky, E. W. Randall, and L. E.67 E. V. Brown, J . Awtev. Chem. SOL, 1957, 79, 3565.J. Thesing and A. Muller, Chem. Ber., 1957, 90, 711.R. Selton, Compt. rend., 1957, 244, 1205.22, 1296; G. B. Bachman and R. M. Schisla, ibid., pp. 858, 1302.J. H. Boyer and S. Kruger, J . Amer. Chem. SOC., 1957, 79, 3552.K. Biemann, G. Buchi, and B. H. Walker, ibid., p. 5558.Sutton, J., 1957, 1769; J. N. Gardner and A. R. Katritzky, J., 1957, 4375SCHOFIELD HETEROCYCLIC COMPOUNDS. 245The products of the Hantzsch pyridine synthesis are the non-basic1 : 4-dihydropyridines ; these do not react with dinitrophenylhydrazinein hydrochloric acid. In contrast, 1 : 2-dihydropyridines suffer ring-opening with dinitrophenylhydrazine.68 The 1 : 2-dihydropyridines (23)are converted 69 by hydrogenation and Grewe-cyclisation into benzomor-phans (24).Catalytic reduction of pyridinium salts in the presence of oneequivalent of alkali gives 2-hydroxy-l-methylpiperidine (25; R = OH) (inequilibrium with the open-chain form), which with benzoyl- or aceto-aceticacid gives the ketone; (25; R = -CH,*COPh or CH,*COMe). Furtherbasification gives A2-tetrahydro-1 : 1'-dimethylanabasine (26). isoQuino-linium salts produce the 3-substituted analogues of (26).70 Oxidation of1-alkylpiperidines with mercuric acetate has been systematically examined;1-methylpiperidine gave the dipyridyl derivative (26) .71 From the cupricacetate oxidation of l-hydroxypiperidine only the dimer of the resultingnitrone was obtained; in contrast, mercuric oxide oxidised l-hydroxy-1 : 2 : 3 : 4-tetrahydroisoquinoline to the nitrone (27).72Pyrimidine is formed in good yield from form-amide and 1 : 1 : 3-triethoxy-3-methoxypropane, and substituted pyrim-idines have been prepared from formamide and various p-dicarbonylDiazines and triazines.Me( 2 6 ) ( 2 7 ) ( 2 5 )R PhR "( 3 2 )derivatives.73 5-Fluoro-uracil and -orotic acid show antibacterial and anti-tumour activity.74 Icthiamine, formed by the action of clam tissue onthiamine, is 4-amino-5- (2-aminoethanesulphonylmethyl) -2-met hylp yrimidine(28); it has been synthesised.7568 L. Kuss and P. Karrer, Helv. Chim. Acta, 1957, 40, 740; H. Kiihnis, W. Traber,and P. Karrer, ibid., p. 751; H. Kiihnis, L. Kuss, and P. Karrer, ibid., p.1670; P. R.Brook and P. Karrer, Annalen, 1957, 6Q5, 1.E. L. May and E. M. Fry, J . Org. Chem., 1957, 22, 1366.7 0 C. Schopf, G. Herbert, R. Rausch, and G. Schroder, Angezv. Chem., 1957, 69, 391.71 N. J. Leonard and F. P. Hauck, jun., J . Amer. Chem. SOC., 1957, 79, 5279.72 J. Thesing and H. Mayer, Annalen, 1957, 609, 46.73 H. Bredereck, R. Gompper, and G. Morloclr, Chem. Ber., 1957, 90, 942.74 R. Duschinsky, E. Pleven, and C. Heidelberger, 3. Amer. Chem. Sot., 1957,79, 4559; C . Heidelberger, N.-K. Chaudhuri, P. Danneberg, D. Mooren, L. Griesbach,R. Duschinsky, R. J. Schnitzer, E. Pleven, and J. Scheiner, Nature, 1957, 179, 663.76 E. E. Kupstas and D. J. Hennessy, J - Amer. Chem. SOC., 1957, 79, 5217, 5220,6222246 ORGANIC CHEMISTRY.New syntheses of 1 : 2 : 4-triazines utilise the reaction between (3-acyl-amino-ketones and hydrazine, and the cyclisation of benzil monoarvl-hydrazones by ammonium acetate.76 With ammonia and carbonyl com-pounds p-mercapto-ketones give dihydro-1 : 3-thiazines (29). 77Large Rings.-Weak bases convert a-bromoacetophenone guanyl-hydrazone into the stable, orange triazacyclooctatetraene (30).78 Acidconverts methyl benzoylglyoxylate a-hydrazone into the tetra-azacyclo-octatetraene (31; R = *CO,Me). This and the parent (31; R = H) aresurprisingly stable; catalytic hydrogenation is slow, and the base (31 ;R = H) undergoes disubstitution with bromine.79Reaction between 2 : 2'-dilithiodiphenyl and mercuric chloride givesthe tetramercura-ring compound (32). The zinc analogue is obtainedsimilarly.80Condensed Ring Systems-%Amino- or 2-mercapto-thiazolines givep-lactams (33; R = *NHAc or *S*CO*CHPh,) with diphenylketen.12bSheehan's work has achieved a brilliant climax with the synthesis ofpenicillin V; D-penicillamine with tert.-butyl phthalimidomalonaldehydategave tert.-butyl ~-a-4-carboxy-5 : 5-dimethyl-a-phthalimido-2-thiazolidinyl-acetate [34; R' = But, R = *N(CO),C,H,]. Cleavage by hydrazine,acylation with phenoxyacetyl chloride, and hydrolysis with hydrogenchloride provided the acid (34; R' = H, R = PhO*CH,CO*NH) which wascyclised by NN'-dicyclohexylcarbodi-imide. *1@- @\ & ' \ N Lj-Jl R'O2C ".;"-f]":6,, ( 3 5 ) (36) Ac( 3 3 ) ( 3 4 )Compounds Ar*X*CH,*CO*Alkyl (X = 0 or S) can be cyclised to 3-alkyl-thionaphthens and -benzofurans, but substances Ar*X*CH,*COAr rearrangeto 2-aryl-thionaphthens and -benzofurans.82Indoles. Fischer cyclisation of arylhydrazones containing electron-releasing meta-substituents produces a preponderance of 6- over 4-substitutedindoles. The opposite is usually true for electron-attracting substituents. 83With ethyl oxalate and sodium ethoxide in pyridine, 4-cyanomethylindolegives the dipolar benzindole derivative (35), but neither 3 : 4-biscyano-methylindole nor the related diacid could be converted into a tricycliccompound.84 However, 4-acetonyl-l-acetyl-3-indolyacetaldehyde under76 V. Sprio and P. Madonia, Gazzetta, 1957, 87, 992; P. V. Laakso, Sir Robert77 F. Asinger, M. Thiel, and W.Horingklee, Annalen, 1957, 610, 1.78 H. Beyer and T. Pyl, Annulen, 1957, 605, 50. '* R. Pfleger and H.-G. Hahn, Chem. Ber., 1957, 90, 2411.*O G. Wittig and G. Lehmann, ibid., p. 875.81 J. C. Sheehan and K. R. Henery-Logan, J . Amer. Chem. SOC., 1957, 79, 1262.82 J. E. Banfield, W. Davies, N. W. Gamble, and S. Middleton, J , 1956, 4971;Robinson, and H. P. Vandrewala, Tetrahedron, 1957, 1, 103.W. Davies and S. Middleton, Chem. and Ind., 1957, 599.D. W. Ockenden and K. Schofield, J., 1957, 3175.H. Plieninger and K. Suhr, Chem. Ber., 1957, 90, 1980SCHOFIELD : HETEROCYCLIC COMPOUNDS. 247Mannich conditions gives the product (36),s5 and p-(6-methoxy-l : 2-di-methyl-3-indoly1)propionic acid can be cyclised at position 4. 86 Skatoleand 2-methylindole are oxidised by ferric chloride to dyes, represented bystructures such as (37).In the presence of amines different productsresult, 2-methylindole giving a product formulated as di-(2-methyl-3-indoleninyl). This is said to differ from di-(2-methyl-3-indolyl), which isconverted into it by hydriodic acid.87 The 3-alkylation of indoles byalcohols and alkoxides can be effected at ordinary pressures. 88 Accordingto conditions, indoles react with vinylpyridines at position 3 or at thenitrogen atom ; methyl vinyl ketone also effects C-alkylation. 89 Hydridereduction of 2-3'-indolylethylpyridinium salts 91 produces tetrahydro-pyridines without cyclisation to p-carbolines. 91Isatin blue, derived from isatin and pipecolic acid, is formulated as thehybrid (38).92Ozone converts heteroauxin into o-formamidobenzoylacetic acid, whichis cyclised by acid to 2 : 4-dihydro~yquinoline.~~ Ascorbigen, from Brassicaoleracw, gives, on hydrolysis, heteroauxin and ascorbic acid, and isrepresented as (39) (possibly the lower part should be Thecolourless acid from reductive hydrolysis of violacein, the pigment of Chromo-bacterium violaceurn, is formulated as (40), and the unstable yellow productof the action of alkali on the pigment as (40; double bond between starred85 H. Plieninger and G. Werst, C k . Berlin., 1956, 89, 2783.F. G. Mann and A. J. Tetlow, J., 1957, 3352.H. von Dobeneck and W. Lehnerer, Chem. Ber., 1957, 90, 161.E. F. Pratt and L. W. Botimer, J. Amer. Chem. SOC., 1957, 79, 5248.A.P. Gray and W. L. Archer, ibid., p. 3554; J. Szmuskovicz, ibid., p. 2819.J. Thesing, H. Ramloch, and C.-H. Willersinn, Chem. Ber., 1956, 89, 2896.Dl R. C. Elderfield, B. Fischer. and J. M. Lagowski, J . Org. Chem., 1957, 22, 1376.92 A. W. Johnson and D. J. McCaldin, J., 1957, 3470.93 C. Schopf, G. Koepke, B. Kowald, F. Schiilde, and D. Wunderlich, Chem. Ber.,94 2. ProchAzka, V. Sanda, and F. Sorm, Chem. Listy, 1956, 50, 333, 654; 1957,1956, 89, 2877.51, 1197; Coll. Czech. Chem. Comm., 1957, 22, 333248 ORGANIC CHEMISTRY.atoms) ; violacein then becomes represented by (41).g5 Oxidation of5 : 6-dihydroxyindoles suggests that a free 3- and a free 4- or 7-position isessential for melanin formation; the red solution formed by oxidising5 : 6-dihydroxy-2 : 3-dimethylindole may contain the related q ~ i n o n e .~ ~N-+-Toluenesulphon yldihydroisoindole is a convenient source of dihydr-is~indole.~’ Pyrrocoline can be obtained easily by treating 2-2’-hydroxy-ethylpyridine N-oxide with acetic anhydride, and pyrolysing the resultingacetate . gSQuinolines, isoquinolines, etc. The anomalous 3-nitration of quinolineis accounted for by initial 1 : %addition of the reagent. An importanttheoretical treatment of the nitration of nitrogen heterocyclics has beengiven.99 The imide (42), from butadiene and methyl glutaconate, can bereduced to trans-A6-octahydro- and trans-decahydro-isoquinoline.lOOPhosphoric oxide in pyridine is a promising reagent for Bischler-Napieral-ski cyclisation.lol 1 : 2-Dihydroquinoline is obtained by reduction ofquinoline with sodium-liquid ammonia.lo2 Reduction of isoquinoline bysodium and liquid ammonia gives initially the 1 : 2-dihydro- and then the1 : 2 : 3 : 4-tetrahydro-compound; the dihydro-compound can trimerise,probably by first isomerising to the 1 : 4-c0mpound.10~Bicyclic compounds with two OY more hetero-atoms. 6-Methoxybenzoxazol-one is partly responsible for the resistance of the maize plant to the cornborer.1“ Indazoles can be prepared by dehydrogenating the readilyavailable 5 : 6 : 7 : 8-tetrahydro-derivatives; indazole analogues of trypt-amine and serotonin have been synthesised.lo5 Oxidation of hydrazonesof 2-acylpyridines and related compounds gives 1 : 2 : 7a- (43) and otherpolyaza-indenes.lo6Hydroxypurines exist in the lactam form ; mercaptopurines havepredominantly thione structures.107 Much effort has been devoted to95 J.A. Ballantine, C. B. Barrett, R. J. S. Beer, B. G. Boggiani, K. Clarke, S.Eardley, B. E. Jennings, and A. Robertson, J., 1957, 2222; J. A. Ballantine, C. B.Barrett, R. J. S. Beer, S. Eardley, A. Robertson, B. L. Shaw, and T. H. Simpson,Proc. Chem. Soc., 1957, 340; R. J. S. Beer, Angew. Chem., 1957, 69, 676.s6 R. I. T. Cromartie and J. Harley-Mason, Biochem. J., 1957, 66, 713.g7 J. Bornstein, S. C . Lashua, and A. P. Boisselle, J . Org. Chem., 1957, 22, 1255.98 V. Boekelheide and W. Feely, J . Org. Chem., 1957, 22, 589.OD M. J. S. Dewar and P. M. Maitlis, J., 1957, 944, 2518, 2521.loo S. Heim&nck and J.TrojBnek, Chem. Listy, 1957, 51, 539; COX Czech. Chem.lol N. Itoh and S . Sugasawa, Tetrahedron, 1957, 1, 45.lo2 W. Hiickel and L. Hagedorn, Chem. Ber,, 1957, 90, 752.loS W. Hiickel and G. Graner, Chem. Ber., 1957, 90, 2017.lo4 E. E. Smissman, J. B. LaPidus, and S. D. Beck, J . Org. Chem., 1957, 22, 220.lo6 C . Ainsworth, J. Amer. Chem. Soc., 1957, 79, 5242, 5345.lo6 J. H. Boyer, R. Borgers, and L. T. Wolford, ibid., p. 678; J. D. Bower and G. R.lo7 D. J. Brown and S. F. Mason, J., 1957, 682.Gomm., 1957, 22, 1167.Ramage, J.. 1957, 4506; J. D. Bower and F. P. Doyle, J., 1957, 727SCHOFIELD HETEROCYCLIC COMPOUNDS. 240synthesising purines , deazapurines, thiazolo- and triazolo-pyrimidines , andbenzo-1 : 2 : 4-triazines as possible metabolite antagonists.lo8The Streptomyces antibiotics , echinomycin and X-948 , which givequinoxaline-2-carboxylic acid as well as amino-acids on hydrolysis , areprobably identical ; X-1008 also gives quinoxaline-2-carboxylic acid.logSome purines react under mild conditions with 1 : 2-dicarbonyl com-pounds , giving pteridines.110 8-Alkyl-2 : 8-dihydro-2-oxopteridines showstrong affinity for a molecule of water but it is argued that this is notstructurally bound.uf 'In aqueous solution lumazine exists as the dilactamform; a third hydroxyl group at C(,) exists predominantly as such, but atC(s) it assumes the lactam forrn.l12 Structure (44; R = CHO or CH,-OH)is suggested113 for a compound from the eyes of Drosophila melanogaster;three compounds have been isolated from this s0urce.1~~ Dihydro- andtetrahydro-pteroylglutamic acid appear to form, with formaldehyde,hydroxymethyl compounds of importance in the enzymic synthesis ofserine.115Cyclisation of the diacetal (45) gives the benzo-dithiophen (46) ; the linear analogue has also been synthesised.l16 Inter-mediates derived from 2-lithio-N-alkylindoles and amino-ketones can becyclised with formaldehyde to tetrahydro-y-carb~lines.~~~Acridinium salts with active methylene compounds give products oftype (4?).u8Glyoxalinophenazines , formed by oxidising o-phenylenediamines in thepresence of ketones, can be reduced to imino-compounds (48) possessinghigh antituberculosis activity .119With alkali, diacetyl gives 5-acetyltetrahydro-2-hydroxy-2 : 5-dimethyl-3-oxofuran which with 4 : 5-diaminouracil forms an intermediate convertedby alkali into lumichrome (49; X = Y = 0), a sequence possibly of bio-synthetic significance.120 The Kuhn-Cook synthesis of alloxazines from5 : 6-diaminopyrimidines and o-quinones succeeded only with polynuclearlo* R.K. Robins and H. H. Lin, J . Amer. Chem. SOC., 1957, 79, 490; J. A. Mont-gomery and C. Temple, jun., ibid., p. 5238; J. A. Montgomery and L. B. Holum, ibid.,p. 2185; W. Pfleiderer and H. Mosthaf, Chem. Bey., 1957, 90, 738; B. S. Gorton andW. Shive, J . Amev. Chem. SOL, 1957, 79, 670; L. Marchal and R. Promel, Bull. SOC.chim. belges, 1957, 66, 406: G. M. Timmis. D. G. I. Felton, H. 0. J. Collier, and P. L.Huskinson, J . Pharm. Pharmacol., 1957, 9, 46; R.F. Robbins and K. Schofield, J.,1957, 3186.lo9 R. Corbaz, L. Ettlinger, E. Gaumann, W. Keller-Schierlein, F. Kradolfer, L.Neipp, V. Prelog, P. Reusser, and H. Zahner, Helv. Chirn. Acta, 1957, 40, 199; J.Berger, E. R. La Sala, W. E. Scott, B. R. Meltsner, L. H. Sternbach, S. Kaiser, S.Teitel, E. Mach, and M. W. Goldberg, Experientia, 1957, 13, 434.Tricyclic comj5ounds.-4. Albert, Biochem. J., 1957, 65, 124.111 W. E. Fidler and H. C. S. Wood, J., 1957, 3980.112 W. Pfleiderer, Chem. Ber., 1957, 90, 2582.llS W. E. Fidler and H. C. S. Wood, J., 1957, 4157.11* M. Viscontini, E. Hadorn, and P. Karrer, Helv. Chzim. Acta, 1957, 40, 579.R. L. Blakley, Biochem. J., 1957, 65, 331.116 D. S. Rao and B. D. Tilak, J . Sci. I n d . Res., India, 1957, 16, B, 65.11' J.Kebrle, A. Rossi, and K. Hoflmann, Angew. Chem., 1957, 69, 683.0. D.imroth and R. Criegee, Chew. Bey., 1957, 90, 2207; F. Krohnke and H. L.119 V. C. Barry, J. G. Belton, M. L. Conalty, J. M. Dennery, D. W. Edward, J. F.lZo A. J. Birch and C . J. Moye. J., 1957, 412.Hohig, ibid., p. 2215.O'Sullivan, D. Twomey, and F. Winder, Nature, 1957, 179, 1013250 ORGANIC CHEMISTRY.quinones; however, it works well with '' dimeric " 4 : 5-dimethyl-o-benzo-quinone, giving derivatives resembling (49) .121Dilute alkali opens the phenoxazone nucleus of actinomycin,122 givingthe anil (50).123 Actinomycin D differs from actinomycin C, 122 only inX CO-NHR CO*NHR CO-NHR(50) (51)having valine in place of alloisoleucine in the peptide chains.lM Alkalinehydrogen peroxide cleaves actinomycins to two fragments, (51) andHO,C*CO*NHR, each having a complete peptide 125 Alkali opensthe lactone groups in the peptide chains of actinomycin C,, giving actino-mycin C, acid.A mixture of diastereoisomeric dimethyl esters of thissubstance has been obtained by constructing the peptide chain, condensingit with 3-benzyloxy-4-methyl-2-nitrobenzoyl chloride, then reducing theproduct and oxidising it .128Cinnabarin (polystictin) is believed to be 3-amino-4-carboxy-5-hydroxy-methylphenoxaz-2-one,127 a structure which accords with the evidencefrom light-absorption data of close similarity between actinomycin, ommo-chromes (see below), and cinnabarin. Gripenberg 128 suggested that thesubstance was 4-carbamoyl-3-hydroxy-5-hydroxymethylphenoxaz-2-one, butan amide group has not been dete~ted.1~' If the first suggestion is correctthe .degradation product which gives 2 : 5-dihydroxybenzoquinone onhydrolysis 128 is presumably 2-amino-5-hydroxybenzoquinone-3-carboxylicacid.Ommochromes are insect pigments, end-products of tryptophan meta-b0lism.1~~ They include ommines of high molecular weight, and ommatinesof low molecular weight.Three ommatines-xanthommatin, rhodommatin,and ommatin D-have been isolated from the butterfly, Vanessa urticae;ommatin C is probably an artefact. The structure of xanthommatin (52)121 T. J. Bardos, B. D. Olsen, and T. Enkoji, J. Amer. Chem. Soc., 1957, 79, 4704.122 Ann. Reports, 1956, 53, 234; A. W. Johnson, Chem.SOC. Spec. Publ. No. 5,123 S. J. Angyal, E. Bullock, W. G. Hanger, W. C. Howell, and A. W. Johnson,124 E. Bullock and A. W. Johnson, J., 1957, 3280.125 Idem, ibid., p. 1602.128 B. Franck, Angew. Chem.. 1957, 69, 237.127 G. W. K. Cavill, P. S. Clezy, and J. R. Tetaz, J., 1957, 2646; Proc. Chem. SOC.,12* J. Gripenberg, Proc. Chem. Soc., 1957, 233.l29 A. Butenandt, Angew. Chem., 1957, 69, 16; 'I Festschrift Arthur Stoll," Bade,1956, p. 82.J., 1957, 1592.1957, 346.1957, p. 869SCHOFIELD : HETEROCYCLIC COMPOUNDS. 261has been proved by degradation to xanthurenic acid (formed from hydroxy-kynurenine) and alanine, by its formation in the ferricyanide oxidation of( 5 2 ) (53)H O( 5 4 )hydroxykynurenine, and by its synthesis from hydroxykynurenine and5 : 8-dihydro-4 : 6-dihydroxy-5 : 8-dioxoquinoline-2-carboxylic acid.129Rhodommatin and ommatin D probably differ from xanthommatin only inthe side-chain~.~~~ As models for the oxidative self-coupling of hydroxy-kynurenine, similar phenoxazone syntheses from 3-hydroxyanthranilic acidand 2-amino-3-hydroxyacetophenone have been examined.131 The oxidationof 4 : 5-diacetyl-3-aminophenoxaz-2-one to 4-acetylbenzoxazolone 132 is inline with work on the actinomycins (see above).Ommochrome reactions 131asuggest that alkali will convert 4 : 5-diacetyl-3-amino- and -3-hydroxy-phenoxaz-2-one into 5-acetyl-3-hydroxyphenoxaz-2-one. Instead, all threesubstances give, through the intermediate (53), the trihydroxy-dibenz-azepinequinone imine (54) ; derivatives of this system are formed directlyfrom 2-amino-3-hydroxyacetophenone by oxidation at pH 8Ci-9.133Phenoxazones also result from oxidation of orcin in aqueous ammonia.Three of the products, a-, p-, and y-amino-orcein are formulated as theracemates (5!5), (56), and (56; with the 3-aryl substituent turned through180’) ; isomerism of the p- and y-compounds depends on restricted r0tation.13~Compounds with a seven-membered ring.2 : 2 : 3-Trimethoxy-l-benz-azepine (57), obtained by reducing methyl o-nitrobenzylidenepyruvate,could not be converted into an azabenzotr~polone.~~~ y-Keto-acids andanilines form the “ A4-homocarbostyrils ” (58) in presence of acids.136Derivatives of 2 : 3 : 4 : 5-tetrahydro-5-oxo-l-benzazepine have been pre-pared by Dieckmann cyclisation of y-o-methoxycarbonylanilinobutyrates.~37130 A.Butenandt, E. Biekert, and R. Beckmann, Annalen, 1957, 607, 207.lal (a) A. Butenandt, J . Keck, and G. Neubert, Annalen, 1957, 602, 61; (b) A.Butenandt, E. Biekert, and G. Neubert, ibid., p. 72.132 A. Butenandt, E. Biekert, and U. Baumann, Arch. Biochem. Biophys., 1957,69, 100.133 A. Butenandt, E. Biekert, and G. Neubert, Annabn, 1957, 603, 200.13* H. MUSSO, H. G. Matthies, H. Beecken, and H. Kramer, Angew. Chem., 1957,69, 178; H. Musso, ibid., p. 396; H. Musso and H. Beecken, Chem. Ber., 1957, 90,1808, 2190.M. Look, Diss. Abs., 1957, 17, 36.136 A. Bertho, Chem. Bey., 1957, 90, 29.lS7 B. D. Astill and V. Boekelheide, J . Amer. Chem. Soc., 1955, 77, 4079; G.R.Proctor and R. H. Thomson, J., 1957, 2302, 2312; J. T. Braunholtz and F. G. Mann,J., 1957, 4174; Chem. and Ind., 1957, 266252 ORGANIC CHEMISTRY.3-Benzoxepines and 3-benzazepines (59; X = 0 or NMe) can be obtained 138from phthalaldehyde and esters (EtO,C*CH,),X (X = 0 or NMe). Catalyticreduction of 2-acetylquinoxalines gives 139 red betaines derived from6-hydroxy-2 : 3-benzodiazepine (as 60). o-Phenylenediamine and o-amino-thiophenol with ctp-unsaturated ketones provide benzodiazepines andbenzothia~epines.~~~ Cyclisation of 2-phenoxyphenyl-pyruvic and -aceticacid gives dibenz[b, floxepins (derivatives of 61; X = 0, Y = CH), anddibenztb, flthiepins (61 ; X = S, Y = CH) are formed similarly. Sulphurcan be extruded from the latter, with the formation of phenanthrenes, andsimilarly dibenzo[b, f]-1 : 4-thiazepines (61; X = S, Y = N) can beconverted into ~henanthridines.1~1Complex oxygen heterocyclics. The pseudo-aromatic benzocyclopent apyran(62) and benzindenopyran resemble azulenes, spectroscopically andchemically.142The O-methyl derivative of dalbergin, from Dalbergia sissoo, is 6 : 7-di-methoxy - 4 - phenyl~oumarin.1~~ 3 : 5 : 7 : 2' : 4' - Pentahydroxyflavanone(dihydromorin) occurs in the heartwood of Morz~s Zactea.l* The flavourof bitter carrots is partly due to (-)-3 : 4-dihydro-8-hydroxy-6-methoxy-3-methylisocoumarin, whose racemic methyl ether has been ~ynthesised.~~~Polycladin and artemisetin are 4' : 5-dihydroxy-3 : 6 : 3' : 7-tetramethoxy-and 5-hydroxy-3 : 6 : 7 : 3' : 4'-pentamethoxy-flavone.1*6 Vitexin, frompuriri wood, is formulated as (63); its tri-0-methyl derivative can beoxidised to 8-f0rmyltri-O-methylapigenin.l~~ Seeding barley leaves containa glucoside, identical with saponarin, which gives vitexin on hydrolysis;analyses of vitexin agree moderately well with structure (63), but forsaponarin agree better with a hexahydroxy side-~hain.1~8 Completely138 K.Dimroth and H. Freyschlag, Chem. Ber., 1956, 89, 2602; 1957, 90, 1623.139 J. A. Barltrop and C. G. Richards, Chem. and Ind., 1957, 1011.140 W. Ried and P. Stahlhoffen, Chem. Ber., 1957, 90, 815, 825, 828; W. Xed and141 J. D. Loudon and L. A. Summers, J., 1957, 3809; J. D. Loudon, A. D. B. Sloan,142 G. V. Boyd, Chem. and Ind., 1957, 1244.145 V.K. Ahluwalia and T. R. Seshadri, J., 1957, 970.144 W. R. Carruthers, R. H. Farmer, and R. A. Laidlaw, J., 1957, 4440.Id6 E. Sondheimer, J . Amer. Chem. Soc., 1957, 79, 5036; W. R. Logan and G. T.1l6 G. B. Marini-Bettolo, S. Chiavarelli, and C. G. Casinovi, Gazzetta, 1957, 87,147 W. H. Evans, A. McGookin. L. Jurd, A. Robertson, and W. R. N. Williamson,lQ8 M. K. Seikel and T. A. Geissman, Arch. Biochem. Bioghys., 1957, 71, 17.W. Marx, ibid., p. 2683.and L. A. Summers, J., 1957, 3814; A. D. Jarrett and J. D. Loudon, J., 1957, 3818.Newbold, Chem. and Ind., 1957, 1485.1185; P. Tunmann and 0. Osaac, Arch. Pharm., 1957, 290, 37.J., 1957, 3510SCHOFIELD : HETEROCYCLIC COMPOUNDS. 253acetylated polyhydroxyflavones are preferentially alkylated at the7-po~ition.14~ That mollisacacidin, from Acacia naollisima, is cis-3 : 4 : 7 : 3' : 4'-pentahydroxyflavan is confirmed by reduction of f ~ s t i n .1 ~ ~Paper chromatography and the use of toluene-+-sulphonic acid as chromo-genic agent serves to identify 2eu~oanthocyanins.l~~Degradation of (-)-epicatechin tetramethyl ether to 1-(3 : 4-dimethoxy-pheny1)-3-(2 : 4 : 6-trimethylphenyl)propan-2-ol having excess of the (+)-enantiomorph, and similar degradation of (+)-catechin tetramethyl ether,shows that (+) <atechin and (-) -epicatechin have opposite configurationsat C(,). Application of Prelog's atrolactic acid method to (-)-epicatechintetramethyl ether confirms Freudenberg's conjectural absolute configuration(64) for (--)-efiicate~hin.l~~ This and other 153 deductions of absoluteconfiguration fix also the configuration of (+) -dihydroquercetin.laThe toxic constituent of immature Australian finger cherry is a tetra-hydroxydimethyldiisovaleryldibenzofuran.155 Alkaline degradation andhydride reduction of athamantin support the structure (65).156 Fulvicacid, a metabolite from Carpenteles crefeldianum, is assigned structure (66).Methyl di-0-methylfulvate readily loses water, and subsequent hydrolysisgave 2-acetyl-7-hydroxy-4 : 5-dimethoxyindane-1 : 3-dione, identical witha wrongly formulated derivative of ~itr0rnycetin.l~~ Conversion of[carboxy1*C]acetic acid into griseofulvin supports the theory of biosynthesisI49 L.Jurd, Chem. and Ind., 1957, 1452.l50 H. H. Keppler, J., 1957, 2721.l5l D.G. Roux, Nature, 1957, 180, 973.152 A. J. Birch, J. W. Clark-Lewis, and A. V. Robertson, J., 1957, 3586.lS3 E. Hardegger, H. Gempeler, and A. Ziist, HeZv. Chim. Acta, 1957, 40, 1819;154 J. W. Clark-Lewis and W. Korytnyk, Chena. am? Ind., 1957, 1418.155 S. Trippett, J., 1957, 414.15* 0. Halpern, P. Waser, and H. Schmid, Helv. Chim. Acta, 1957, 40, 758; cf.15' F. M. Dean, R. A. Eade, R. Moubasher, and A. Robertson, J., 1967, 3497.A. B. Kulkarni and C. G. Joshi, J . Indian Chem. Soc., 1957, 34, 217.Ann. Reports, 1941, 38, 223254 ORGANIC CHEMISTRY.by head-to-tail linkage of acetic acid units.15* 2-Acetyl-4 : 6-dimethoxy-coumaran-3-oneJ by addition to methyl vinyl ketone and cyclisation of theproduct gives the dioxogrisen (67).Degradation of tri-O-ethylwedelo-lactone proves the structure (68) for wedelolactone ; 160 tri-O-methyl-wedelolactone has been synthesised and converted into wedelolactone.161The structure (69) is suggested for the pigment sclerotiorin, from Peni-cillium sclerotiorum ; this compound exemplifies a group of substanceswhich, because of the ease with which they react with ammonia and primaryamines, giving isoquinoline derivatives, have been called azaphilones.162K. S.9. ALKALOIDS.SEVERAL interesting review articles have appeared in a publication 1 inhonour of A. Stoll’s seventieth birthday: one of these, on some biogeneticaspects of phenol oxidations, includes a number of interesting speculationson the biogenesis of alkaloids; those on pyrrolizidine alkaloids, on aromaticerythrina alkaloids, and on ajmaline have also been published in AngewandteChemie.Among the more interesting results of biosynthetic tracer work there isthe demonstration that, in barley, phenylalanine is the precursor ofhordenine ; this involves hydroxylation of a non-phenolic benzene ring.Further work has confirmed the hypothesis that ornithine is metabolised toa symmetrical CJ unit before incorporation as the pyrrolidine portion ofnicotine.* Ricinine, the alkaloid of the castor bean, has been shown to bederived from nicotinic acid.5Tropane Group.-Two reviews of recent developments in this group haveappeared.l, The absolute configuration of valeroidine (1) has been deducedby an application of Hudson’s rule to a derivative containing a a-lactonegrouping between the 6-hydroxyl and an N-carboxymethyl Thereare the beginnings of an absolute stereospecific synthesis in this group in thesynthesis of (S)-( +)-6 : 7-dihydroxytropan-3-one [( +)-alloteloidinone] fromdiethyl (+)-tartrate.8 A neat synthesis of scopoline (2) by thermal de-composition of teloidine carbonate has been a~hieved.~ A novel synthesis158 A.J. Bjrch, R. A. Massy-Westropp, R. W. Richards, and H. Smith, Proc. Chem.SOC., 1957, 98.15O F. M. Dean and K. Manunapichu, J., 1957, 3112.l60 T. R. Govindachari, K. Nagarajan, B. R. Pai, and P. C. Parthasarathy, J.,1957, 545.161 W. J. Bowyer, A. Robertson, and W. B. Whalley, J., 1957, 542; T. R.Govindachari, K. Nagarajan, and P. C. Parthasarathy, J., 1957, 548; N.R. Krishna-swamy and T. R. Seshadri, J . Sci. Ind. Res., India, 1957, 16, B, 268.162 A. D. G. Powell, A. Robertson, and W. B. Whalley, Chem. Soc. Sfiec. Publ. No.5, 1956, p. 27. (But see J., 1957, 4913 et seq.)1 Festschrift Arthur Stoll, Birkauser Verlag. Basel, 1957.2 Angew. Chem., 1957, 69, 5, 33, 40.J. Massicot and L. Marion, Canad. J . Chem., 1957, 35, 1.E. Leete and K. J. Siegfried, J. Amer. Chem. Soc., 1957, 79, 4529.5 E. Leete and F. H. B. Leitz, Chem. and Ind., 1957, 1572.6 G. Fodor, Tetrahedron, 1957, 1. 87.7 G. Fodor, I. Vincze, and J. Toth. Experientia, 1957, 13, 183.8 E. Hardegger and H. Furter, Helv. Chim. Acta, 1957, 40, 872; cf. K. Zeile and9 Idem, ibid., p. 2800.A. Heusner. Chem. Ber., 1957, 90, 1869SMITH : ALKALOIDS.255of the tropane system involves the interaction of cycloheptatriene-l-, -3-, or-4-carboxylic ester and methylamine.1° Structure (3) has been proposedfor dioscorine; 11 in this work, the presence of the spiro-6-lactone group wasproved, but not its position on the tropane system; the work leaves twopossible positions for it, 2 and 7, the former being preferred on biogeneticgrounds.Lupinane Group.-The structures of two further C,, lupin alkaloids havebeen elucidated: aphyllidine (4), by oxidative and spectral studies,12 andbaptifoline (5) by conversion into (-)-13-hydroxylupanine, the (+)-enantiomer of which is k n o ~ n . 1 ~ In a most interesting paper,l* Bohlmannand his co-workers repeat previous work by other workers15 up to thepreparation of a mixture of stereoisomers of compound (6), which is nowseparated chromatographically into the four possible stereoisomers.Thesestereoisomers, after oxidation of -CH,*OH to -C02H , are separatelyconverted into the four stereoisomers of the base (7). One of these, oxy-sparteine, had already been synthesised from the mixture; l5 another isnow found to be identical with (-+)-aphylline, which is thus synthesised forthe first time.The study of the rate of dehydrogenation of >N*CH< to >N+=C<by mercuric acetate, which has been applied with such success to con-formational analysis in the indole group,16 has been turned to the sparteinelo C. Grundmann and G. Ottmann, Annulen, 1957, 605, 24.l1 A. R. Pinder, Chem.and Ind., 1957, 1240.l2 F. Galinowski, P. Knoth, and E. Garisch, Monaish., 1957, 88, 143.l3 M. Martin-Smith and L. Marion, Canad. J . Chem., 1957, 35, 37.l4 F. Bohlmann, W. Weise, H. Sander, G.-G. Hanke, and E. Winterfeld, Chem. Ber.,l6 E. Wenkert and D. K. Roychaudhuri, J. Org. Chem., 1956, 21, 1315; F. L.1957, 90, 653.G. Clemo, W. Morgan, and R. Raper, J., 1949, 663.Weisenborn and P. A. Diassi, Chem. and Ind., 1956, 2022256 ORGANIC CHEMISTRY.and the matrine group: the stereochemistry deduced for matrine (8) andfor allomatrine (9) agrees with that deduced on other grounds by a differentschool.l* The latter workers also describe the synthesis of (&)-aZZo-matridine.Pyridine Group.-Anibine has been shown l9 to have the novel structure(10).The synthesis of gentianine has now been achieved.20 The absoluteconfiguration of the or-carbon in the monosubstituted piperidine alkaloidshas been shown to correspond with that of the L-amino-acids.21 Applicationof counter-current distribution to the separation of the mixture of minoralkaloids from Lobelia iny7ata has revealed the presence of at least thirtynew bases; the structures of six of these have been elucidated. A newnomenclature for the lobelia alkaloids, rendered necessary by the abovefindings, is proposed.22Quinoline Group.-A new type, 2-phenyl-4-methoxyquinoline, has beenisolated from the leaves of Lunasia amara B l a n ~ o . ~ ~isoQuinoline Group.-A new general synthesis of the protoberberinesystem has been described,% and has been used in the synthesis of (5)-ophiocarpine (11).By far the most interesting event in this group has beenthe isolation of the aldehydo-base (12) from ipecacuanha alkaloid mother-liquors: 25 this labile alkaloid forms the biogenetic link between thenumerous benzylisoquinoline alkaloids and the emetine bases, and givesstrong support to earlier speculations on the biogenesis of emetine.26 Theconversion of this aldehyde (12) into emetine further clearly demonstratesthe identity of the stereochemistry of the two molecules. This is furtherthe first authenticated occurrence of a free aldehyde group in an alkaloid:its analogues in the indole group, such as corynantheine, are all aldehydeenol ethers.Battersby and his co-workers have also achieved the elucidation of theabsolute configuration at position 1' of emetine (13), by molecular-rotation1 7 F.Bohlmann, Angew. Chem., 1957, 69, 641; F. Bohlmann, W. Weise, and D.Rahtz, ibid., p. 642.18 K. Tsuda and H. Mishima, Pharm. Bull. (Japan), 1957, 5, 285.1 9 W. B. Mors, 0. R. Gottlieb, and C. Djerassi, J . Amer. Chem. SOL, 1957, 79, 4507.20 T. R. Govindachari, K. Nagarajan, and S. Rajappa, J., 1957, 2725.21 H. C. Beyerman, J. Eenshuistra, and W. Eveleens, Rec. Trav. chim., 1957, 76,415; R. LukeS, J. Kloubek, K. BlAha, and J. KovAf, Coll. Czech. Chern. Comm., 1957,22, 286.22 C. Schopf and T. Kauffmann, with P. Berth, W. Bundschuh, G. Dummer, H.Fett, G. Habermahl, E. Wieters, and W. Wust, Annalen, 1957, 608, 88.23 S. Goodwin, A. F.Smith, and E. C. Homing, J . Amer. Chenz. SOL, 1957, 79, 2239.Z4 T. R. Govindachari and S. Rajadurai, J., 1957, 557; T. R. Govindachari, S.Rajadurai, M. Subramanian, and N. Viswanathan, ibid., p. 2943.86 A. R. Battersby, G. C. Davidson, and B. J. T. Harper, Chem. and Ind., 1967, 983.26 R. Robinson, Nature, 1948, 162, 624SMITH : ALKALOIDS. 257studies on the oxidation product (14), and of the relative configuration ofthe quinolizidine portion by conformational analysis of two products of thedegradation of 0-methylpsychotrine and by synthesis, from trans-3 : 4-diethylcyclopentanone, of the base (15), shown to be identical with the Wolff-Kishner reduction product of the aldehyde-alkaloid (12) .27 van Tamelen andOMeOMehis co-workers also arrived at the relative configuration of the quinolizidineportion of the emetine molecule 28 by a synthesis of the base (15), showing itto be identical with a compound obtained from an intermediate used in theRussian synthesis of emetine.29H E tIndole Group.-Flavopereirine, one of the alkaloids of GeissospermumZaeue Baill., has been given structure (16), most interesting because it is thefirst case in this group of a degraded structure, being obviously derived froma corynantheine-like precursor by loss of three skeletal carbon atoms.30 Inanother brilliant example of the art of separating complex mixtures ofalkaloids, H.Schmid, P. Karrer, and their co-workers have isolated twelvemore alkaloids from the bark of Strychnos melinonziana One ofthese is flavopereirine (16).One of the two which had previously beenisolated,32 melinonine-B, has been shown 33 most probably to have structure(17) ; dehydrogenation gives a noralstyrine, the 4'-ethyl group having beenreplaced by methyl, and, what is very disturbing, dehydrogenation bypalladium yields yobyrine (18)-this means that an isolation of yobyrine nolonger can be taken to indicate the presence of a homocyclic ring E.27 A. R. Battersby, R. Binks, D. Davidson, G. C. Davidson, and T. P. Edwards,Chem. and Ind., 1957, 982; A. R. Battersby and S. Cox, ibid., p. 983.28 E. E. van Tamelen, P. E. Aldrich, and J . B. Hester, jun., J . Amev. Chem. SOC.,1967, '79, 4817.29 R. P. Evstigneeva, R. S. Livshits, M. S. Bainova, L. I. Zakharin, and N. A.Preobrazhensky, J .Gen. Chem. (U.S.S.R.), 1952, 22, 1511 (U.S. translation).30 0. Bejar, R. Goutarel, and M.-M. Janot, Comfit. rend., 1957, 244, 2066.31 E. Bachli, C . Vamvacas, H. Schmid, and P. Karrer, Helv. Chim. Ada, 1957, 40,32 E. Schlittler and J. Holil, ibid., 1952, 35, 29.33 C. Vamvacas, W. von Philipsborn, E. Schlittler, H. Schmid, and P. Karrer, %id.,1167.1957, 40, 1793.REP.-VOL. LIV 258 ORGANIC CHEMISTRY.Elucidation of the stereochemistry of the alkaloids in the yohimbane andrelated groups is becoming an increasingly specialised activity, involvingmainly careful analysis of infrared spectra 34 and of rates of dehydrogen-ati0n.~5An interesting synthesis,36 that of 17-demethoxydeserpidine, involvesformation of a &-DIE ring junction as one of the last steps, this beingachieved by catalytic hydrogenation of compound (MA), which also bringsthe substituents in ring D into the required orientation.The stereochemistryof raunescine, i~oraunescine,~~ and psezdoreserpine 38 has been completelyworked out.Mainly on the basis of ultraviolet and infrared studies, corynoxeine hasbeen shown 39 to be the oxindole analogue (19) of corynantheine. This mostinteresting molecule looks very much like a " missing link '' between theyohimbine and the strychnine series, and may well point the way to asolution of the gelsemine problem. Corynoxine has an ethyl in place of thenvinyl, but has a different stereochemistry, for it is not identical with di-hydrocorynoxeine. The latter has been shown to be identical with rhyn-c ~ p h y l l i n e .~ ~ * ~ ~ Another member of the ajmaline group has been found invomalidine, to which structure (20) has been gi~en.~1 The structures ofsarpagine 42 and C-alkaloid-T 43 have been the subject of speculation:formula (21) has been proposed for sarpagine on the basis of the phenolicproperties of the base, its ultraviolet spectrum, and ozonolysis to acet-aldehyde ; in C-alkaloid-T, the methyl ether of sarpqgine contaminated with34 E. Wenkert and D. K. Roychaudhuri, J. Amer. Chem. SOC., 1956, 78, 6417;N. Neuss and H. E. Boaz, J. Org. Chem., 1957, 22, 1001.35 E. Wenkert and D. K. Roychaudhuri, J. Amer. Chem. SOC., 1957, 79, 1619.36 F. L. Weisenborn, ibid., 1957, 79. 4818.37 C. F. Huebner and E.Schlittler, ibid., p. 250; E. E. van Tamelen and C. W.38 M. W. Klohs, F. Keller, R. E. Williams, and G. W. Kusserow, ibid., p. 3763.39 N. An Cu, R. Goutarel, and M.-M. Janot, Bull. SOC. chim. France, 1957, 1292.40 J . C. Seaton and L. Marion, Canad. J. Chem., 1957, 35, 1102.4 1 A. Hofmann and A. J. Frey, Helv. Chim. Ada, 1957, 40, 1866.42 D. Stauffacher, A. Hofmann, and E. Seebeck, ibid., p. 508.4s W. Arnold, W. von Philipsborn, H. Schmid, and P. Karrer, ibid., p. 705.Taylor, ibid., p. 5256SMITH : ALKALOIDS. 2 59the vinyl isomer, the presence of the -CH,*OH grouping has been demons-trated. The proposed structures assume a relationship with the ajmalinegroup. Lochnerine is the pure methyl ether of sarpagine.& Some 80 yearsafter its isolation, aspidospermine has only now been found to contain anN-methyl group : 45 this was detected by nuclear magnetic resonancespectroscopy and its presence was then confirmed by standard methods.An analysis of available data, including a reversible BrCN degradationclaimed to involve a remarkable rearrangement, leads to the proposal ofthe novel structure (22) for the alkaloid as a working hypothesis.A newidea, ortho-meta-fission of the benzene ring in the phenylalanine unit, is used 45to derive a plausible scheme for the biogenesis of compound (22).Structures (23; R = H, R’ = OMe; R = OMe, R’ = H; and R = R’ =H), also of a completely new type, are proposed for ibogaine, tabernanthine,and ibogamine respe~tively.~~ This is the result of a brilliant deduction ofthe structure of the two selenium dehydrogenation products of ibogaine,N/ Me%Ec A - Me0 A-(24) and (25; R = OMe) : although neither has been synthesised, the authorreports the synthesis by another group of workers4’ of compound (25;R = H) which was obtained by dehydrogenation of ibogamine.Voacangine has been converted into ibogamine by decarboxylation ofvoacangic acid and by thermal elimination of formaldehyde from theproduct of reduction of voacangine by lithium aluminium hydride.Theseobservations have led to the proposal of structure (26) for the alkaloid.48An ingenious and convincing scheme for the biogenesis of the iboga alkaloidsand of voacangine has been proposed.49 Partial structure (27) has been putforward 50 for ulein, the alkaloid of Aspidosperma ulei, Mgf.; this does notseem to have any relation to the other indole alkaloids.The main degrad-ation product, an ethyl-n-propylcarbazole, has not yet been synthesised.44 J. Poisson, J . le Men, and M.-M. Janot, Bull. SOC. chim. France, 1957, 610.4 5 H. Conroy, Y. R. Brooks, M. K. Rout, and W. Silverman, J. Amer. Chem. SOL.,46 W. I. Taylor, ibid., p. 3298.47 MacPhillamy, Lucas, and Dzieman, unpublished work.48 F. Percheron, A. leHir, R. Goutarel, and M.-M. Janot, Compt. rend., 1957,49 W. I. Taylor, Experientia, 1957, 13, 454.6O J. Schmutz, F. Hunziker, and R. Hirt, Helv. Chim. Acta, 1957, 40, 1189.1957, 79, 1763.245, 1141260 ORGANIC CHEMISTRY.Four new alkaloids have been isolated from the ergot fungus growing ona tropical millet ; 5 l three of them are hydroxy-derivatives of agroclavineand elymoclavine; the fourth, chanoclavine, has been given structure (28).Pyrrolizidine Group.-Molecular-rotation arguments have led to proposalsfor the absolute configuration of the necines ; 52 thus, isoretronecanol hasbeen given structure (29).Phenanthridine Group.-The already large number of alkaloids in thisgroup is still increasing, eleven new ones having been added to it this yearby H.-G.Boit and his co-worker~.~~ Belladhe,% which has been givenstructure (30), is so far the simplest of the Amaryllidaceae alkaloids, andmay well represent the skeleton of the precursor of all the others. Biogeneticschemes on these lines are described.M*55 Galanthamine has been shown 56to have structure (31), which had been predicted on biogenetic grounds.55It is remarkable that the immediate precursor of the alkaloid (31) in thebiogenetic scheme,55 the corresponding a@-unsaturated ketone, ha5 sub-sequently turned out to be the alkaloid nar~edine.~'Diterpene Group.-Ajaconine has been shown to contain the atisineskeleton by degradation to an oxygen-free base obtainable from atisine; 58later work 59 has in fact shown it to be a hydroxyatisine. This is the firstdemonstration of the atisine skeleton in a delphinium alkaloid. Napellonine,an aconite alkaloid, has been shown to contain a modified Garrya-typeskeleton: e0 the main point of interest in the structure proposed, (32), is5l A.Hofmann, R. Brunner, H.Kobel, and A. Brack, Helv. Chim. Acta, 1957,40,1358.52 N. J. Leonard, Chem. and I n d . , 1957, 1455.6* H.-G. Boit and H. Emke, Chem. Ber., 1957, 90, 57, 369; H.-G. Boit, S. Uyeo,and H. Yajima, ibid., p.. 363; H.-G. Boit, W. Stender, and A. Beitner, ibid., p. 725;H.-G. Boit and W. Dopke, ibid., p. 1827; H.-G. Boit, W. Dopke, and W. Stender,ibid., p. 2203.64 E. W. Warnhoff, Chem. and Ind., 1957, 1385.55 D. H. R. Barton and T. Cohen, ref. 1, p. 126.5 6 Personal communication from S. Uyeo to H.-G. Boit in ref. 57.5' H.-G. Boit, W. Dopke, and A. Beitner, Chem. Ber., 1957, 90, 2197.5 8 D. Dvornik and 0. E. Edwards, Chem. and Ind., 1957, 952.5@ S. W. Pelletier, ibid., p. 1670.60 K. Wiesner, 2. Valenta, J. F. King, R. K. Maudgal, L. G. Humber, and Sh6 It6,ibid., p.173SMITH : ALKALOIDS. 261the presence of an extra ring postulated to involve the linking of positions17 and 8. The arguments for this are based largely on the interpretationof infrared spectra and pK, data.By assuming skeletal identity with lycoctonine, structures have beententatively proposed for delcosine 61 and aconitine.62 A structure proposed 63for delphinine has been withdrawn.64Miscellaneous.-The structure of muscarine has at last been elucidated: 65X-ray crystallography revealed it to be (33), in agreement with the formationof the rt-hexyltrimethylammonium ion by chemical degradati0n.6~0In other work on muscarine, a most interesting application of catalyticoxidation resulted in a good yield of the corresponding ketone, shown byits infrared spectrum to be of cyclopentanone type.66 Of three groups whohave reported synthetic work, one describes the formation of a mixture ofstereoisomers which contains about 30% of muscarine iodide, from whichno crystalline material could be i~olated,~' another a non-stereospecificsynthesis leading to crystalline (&)-muscarhe iodide,G8 and a third asynthesis which reveals the absolute configuration of muscarine 6@ to berepresented by (33).The last synthesis starts from L-glucosaminic acid andproceeds by L-chitaric acid, its dimethylamide (34) ,. the tritoluene-p-sulphonate of which on reduction by lithium aluminium hydride gives a lowyield of muscarine, isolated as the tetraphenylboronate.6Me ( 3 6 )The admirably systematic degradation of nupharidine, 70 one of thealkaloids of the rhyzome of the Japanese variety of the water-lily, hasbrought to light a novel sesquiterpenoid structure of quinolizidine type, (35).R. Anet, D.W. Clayton, and L. Marion, Canud. J . Chem., 1957, 35, 397.62 W. Schneider, Nuturwiss., 1957,44,492; W. Schneider and H. Tausend, ibid., p. 512.63 See Ann. Reports, 1956, 53, 249.64 W. A. Jacobs and S. W. Pelletier, J . Org. Chem., 1957, 22, 1428.65 F. Jellinek, Actu Cryst., 1957, 10, 277; F. Kogl, C. A. Salemink, H. Schouten,6 6 C. H. Eugster and P . G. Waser, Helv. Chim. Acta, 1957, 40, 888.87 F. Kogl, H. C . Cox, and C. A. Salemink, Annulen, 1957, 608, 81.6 8 C. H. Eugster, Helv. Chim. Actu, 1957, 40, 2462.6 s E. Hardegger and F.Lohse, ibid., p. 2383.7 0 M. Kotake, S. Kusumoto, and T. Ohara, Annalen, 1957, 606, 148.and I;. Jellinek, Rec. Trav. chim., 1957, 76, 109262 ORGANIC CHEMISTRY.A neat synthesis of cryptopleurine (36) has been de~cribed.~~ Very interest-ing is the appearance of an analogous structure in tylophorine, for whichformula (37) was advanced. 72Further oxidative experiments have enabled Wiesner and his co-workers 73to propose structure (38) for annotinine: this represents a completion of the0 ,q 0%.N N(38)partial structure proposed63 by the same school in 1956. This brilliantdeduction of structure (38) for annotinine was later spectacularly confirmedby X-ray crystallographic determination 74 of the structure of the corres-ponding bromohydrin (39).G.F. S.10. STEROIDS.A COMPILATION of the optical rotations of steroids1 has been produced,which is incidentally of great value in providing a survey of steroid literatureup to 1954.Physicochemical measurements. Optical rotatory-dispersion measure-ments have been used to correlate the absolute configurations of steroidswith those of other natural products.2Infrared spectroscopic studies have been made of the carbonyl absorptionin a-halogeno- steroid^,^ and in steroidal 16 : 17-ketols and keto-acetates!of the absorptions in the C-H stretching region modified by the presence ofepoxide groups and methoxyl group^,^ and of the absorption of 1 : 2-di-substituted cis-ethylenic centres.A mass spectrometer has been used in the determination of the molecularweights of steroids; the method also affords information on the length ofthe side chain (if any) which is split off in the process.General reactions.A method for the preparation of 3p-fluoro-A5-steroidsinvolves treatment of the corresponding toluene-P-sulphonates with mag-nesium iodide, and then with silver fluoride in acetonitrile and ~ y l e n e . ~7 1 C. K. Bradsher and H. Berger, J. Amer. Chem. SOC., 1957, 79, 3287.72 T. R. Govindachari, M. W. Lakshmikantham, K. Nagarajan, and B. R. Pai,73 K. Wiesner, W. A. Ayer, L. R. Fowler, and 2. Valenta, ibid., p. 564.74 M. Przybylska and L. Marion, Canad. J . Chem., 1957, 35, 1075.1 J. P. Mathieu and A. Petit, ‘‘ Tables de Constantes et Donnkes Numeriques,” 6,“Constantes SClectionn&, Pouvoir Rotatoire Nature], I, StCroYdes,” Masson et Cie,Paris, 1956.C. Djerassi, R.Riniker, and B. Riniker, J. Amer. Chem. SOC., 1956, ‘78, 6362.R. N. Jones and G. Roberts, Chem. and Ind., 1957, 1269.H. B. Henbest, G. D. Meakins, B. Nicholls, and K. J. Taylor, J., 1957, 1459. * H. B. Henbest, G. D. Meakins, B. Nicholls, and A. A. Wagland, ibid., p. 1463.7 H. B. Henbest, G. D. Meakins, B. Nicholls, and R. A. L. Wilson, ibid., p. 997. * P. de Mayo and R. I. Reed, Chem. and Ind., 1956, 1481.Chem. and Ind., 1957, 1484.3 E. G. Cummins and J . E. Page, J., 1957, 3847.T. N. Jacobsen and E. V. Jensen, ibid., 1957, 172; c f . C. W. Shoppee and G. H. R.Summers, J . , 1957, 4813BLADON : STEROIDS. 263The other 3p-halogeno-A5-steroids can be made by treating the corres-ponding alcohols with an aluminium halide.1° 17p-Hydroxyl groups areunaffected by aluminium chloride, and so this reagent is of value in selectivelyreplacing the 3p-hydroxyl group in 38 : 17p-diok.The solvolysis of salts and methyl esters of cholesteryl and cholestanylhydrogen sulphates has been studied, and the mechanism of the reactiondiscussed.llOxidation of A5-stenols with chromic anhydride-sulphuric acid in acetoneaffords good yields of A5-3-ketonesJ and after acid treatment, A4-3-ketones.12All the isomeric cholestane-2 : 3-diols are now known,13 and severall-oxygenated derivatives in the A/B-cis-series have been made from methyl1 f3 : 3~-dihydro~yetiocholanate.~~Reagents: I , Zn-&OH.2 , Zn-AcOH o n semicarbazone with subsequent regeneration ofketone.3, HCI-EtOH.Reductive removal of 17cc-, 17p-, and 21-acetoxy-groups in the corticalhormone series has been studied. The accompanying formulz (1-6) showthe chief transf 0rmations.lBoth allopregnane-3p : 17a : 20-triols (7) are converted into the 20-ketone(8) by acid treatment.lCExperiments with 2-, 3-, 4-, 6-, and 7-amino-steroidsJ and with 6-amino-3 : 5-cyclo-steroids have shown that the de-amination of equatorial amineswith nitrous acid gives the corresponding equatorial alcohols in good yield.The axial amines give the axial alcohols together with varying amounts ofelimination products. l7Representative saturated 3-, 12-, 17-, and 20-oxo-steroids, and A5-7-ketones and Als-20-ketones have been shown to react in the normal way withmethylenetriphenylphosphorane (the Wittig reagent) , to yield the corres-ponding methylene compounds.18lo J.Broome, B. R. Brown, and G. II. li. Summers, J., 1957, 2071.l1 J. McKenna and J. K. Norymberski, ibid., pp. 3889, 3893.l2 C. Djerassi, R. R. Engle, and A. Bowers, J . Org. Chem., 1956, 21, 1547.l3 H. B. Henbest and M. Smith, J., 1957, 926; C. W. Shoppee, D. N. Jones, andG. H. R. Summers, ibid., p. 3100.l4 W. Schlegel and C. Tamm, Helv. Chim. Acta, 1957, 40, 160.l6 R. S. Rosenfeld, J . Amer. Chem. SOC., 1957, 79, 5540; H. L. Slates and N. L.Wendler, J . Org. Chem., 1957, 22, 498.l6 D. K. Fukushima and T. F. Gallagher, J . Biol. Chem., 1957, 226, 725.l7 C. W. Shoppee, D. E. Evans, and G.H. R. Summers, J., 1957, 97; D. E. Evansand G. H. R. Summers, ibid., p. 906; C. W. Shoppee, R. J. W. Cremlyn, D. E. Evans,and G. H. R. Summers, ibid., p. 4364.F. Sondheimer and R. Mechoulam, J . Amer. Clzem. SOC., 1957, 79, 5029264 ORGANIC CHEMISTRY.Lithium tri-tert.-butoxyaluminium hydride reduces steroid 3-ketones togive equatorial alcohols in yields of over 90y0.19Lund 2o has shown that electrolytic reduction of A4-3-oxo-steroids givesrise to pinacols (9). In the particular case of the doubly unsaturatedl-dehydrotestosterone, either of two isomeric pinacols can be obtained,depending on the pH of the solution, but the arguments used by the authorto assign configurations to these pinacols are open to question.Chloranil has found a use as a dehydrogenating agent for A4-oxo-cortico-steroids.21 Double bonds are introduced at position 5 and under morevigorous conditions at position 1 (formulae 10-13).Reagents: I, Chloranil-xyfene at the b.p.2, Chloranif-n-pentyl alcohol at the b.p.Velluz and his collaborators22p23 have studied the reactions of the di-hydroperoxides formed by treating 3-, A4-3-, 17-, and 20-oxo-steroids withhydrogen peroxide. Those derived from 20-ketones (14) give 17-acetoxy-compounds (15) on treatment with foimic acid, while with mineral acids,derivatives of tetraoxacyclohexane (16) are formed.22The 17 : 17-di-hydroperoxide (18) derived from 3a-acetoxy-5P-androstane-11 : 17-dione (17), on treatment with acetic anhydride andpyridine, gives a lactone (19); when heated in an inert solvent it gives theOAc(14) (16)Reagents: I , H*CO,H.2, AcOH-H,SO,.stereoisomeric lactone (20). Both lactones are converted into the knownunsaturated acid (21) by base.23 The first of these lactones is also formedtogether with small quantities of the isomeric lactone (22) by oxidation ofthe 17-ketone (17) with peracids.=l9 0. H. Wheeler and J. L. Mateos, Chem. and Ind., 1957, 395.20 H. Lund, Acta Chem. Scand., 1957, 11, 283.21 E. J. Agnello and G. D. Laubach, J . Amer. Chem. Soc., 1957, 79, 1257.22 J. Warnant, R. Joly, 3. Mathieu, and L. Velluz, Bull. SOC. chim. Fvance, 1957,23 L. Velluz, G. Amiard, J. Martel, and J. Warnant, Compt. rend., 1957, 244, 1937.2* A. Lardon, J. Schmidlin, A. Wettstein, and T. Reichstein, Helv.Chim. Ada,1957, 40, 662; cf. N. L. Wendler, D, Taub, and H. L. Slates, J . Amer. Chem. SOC.,1955, 77, 3560; M. F. Murray, B. A. Johnson, R. L. Pederson, and A. C . Ott, ibid.,1956, 78, 982.331; L. Velluz, G. Amiard, J. Martel, and J. Warnant, ibid., p. 879BLADON : STEROIDS. 265The unsaturated acids (21) and (25; A/B-tYalaS, 3B-OAc) [obtained by asimilar Baeyer-Villiger reaction from (17) and the D-homo-ketone (23)],Reagents: I, H,O,-ButOH. 2, Xylene or Bu20 at b.p. 3, Ac20-pyridine. 4, Ph*C03H orAcOZH. 5, OH-. 6 , CFSCOSH. 7, Ph-CHO-HCI. 8, (COCI),; CH2N2; HI. 9, OH-. 10,LiAIH,; 0,.or -OH.In formulae 17-22, the suffix " a " 3 A/B-Cis, 3a-OAc or -OH; I ' b " = A/B-tfans, 3P-OAchave been used as intermediates in an attempted partial synthesis of aldo-sterone.The masked Waldehyde group was introduced via an inter-mediate benzylidene derivative (26), epimerization at position 14 occurringsimultaneously. The subsequent cyclisation steps (26 _t 28) were influencedmarkedly by the configuration at C(la (cf. 25 _t 30 - 31), and the desired(clD-trans, 14a-H : 17 p-CO-CH,) structure was not achieved.25The reactions of a wide range of steroid epoxides with the boron tri-fluoride-ether complex 26 (leading to ketones) and with metal-amine reducingsystems 27 have been studied.Steroids containing an 8 : 9-double bond (hitherto difficultly accessible)25 D. H. R. Barton, A. da S. Campos-Neves, and A. I. Scott, J., 1967, 2608.26 H. B. Henbest and T. I. Wrigley, ibid., p. 4596.'7 A.S. Halsworth and H. B. Henbest, &bid., p. 4604266 ORGANIC CHEMISTRY.are formed by reducing 1 l-oxygenated As(g)- or &oxygenated hg(l1)-com-pounds with lithium and ethylamine 28 (32 _t 34, R = H; 33 _t 34,R = OH).Interest in derivatives in which one or more of the ring junctions B/Cand C/D has an abnormal configuration has continued. The chart (formulae35-48) summarises the findings of two groups working in the sapogenin 29and ergostane 30 series. The former group extended the work to synthesesReagents: I, OH-. 2, Li-NH3 (liquid). 3, H,-Pd-C. 4, LiAIH,; Ac,O-AcOH. 5, Kishner-Wolff reduction. 6, Kishner-Wolff (forcing conditions). 7, LIAIH,; POC13-pyridine. 8, H,-Pt-AcOH.of 8cc-proges terone and 8a-tes tost e r ~ n e . ~ l Work on 14p-compounds hasincluded the total synthesis of 14p-cestrone methyl ether.32 An analysis ofthe conformations of all thirty-two isomeric 13p-methylstan-3~-ols has beenpublished.33to have the structure (49) " Ketone 104 " is now believed by Fieser28 A.S. Halsworth, H. B. Henbest, and T. I. Wrigley, J . 1957, 1969.2s C. Djerassi and G. H. Thomas, J . Amer. Chem. SOC., 1957, 79, 3835.80 J . B. Bream, D. C. Eaton, and H. B. Henbest, J . , 1957, 1974.3 l C. Djerassi, A. J. Manson, and H. Bendas, Tetrahedron, 1057, 1, 22.32 W. S. Johnson and W. F. Johns, J . Amer. Chevn. SOC., 1957, 79, 2006.33 J. Castells, Pub,?. Ivzst. Quim. Alonso Barba, 1956, 10, 84.34 L. F. Fieser, in " Festschrift Arthur Stoll," Verlag Birkhauser, Basel, 1957, p. 489BLADON : STEROIDS. 267and to be an oxidation product of cholesterol itself, and not of a companionof ch~lesterol.~~Photochemical oxygenation of cholesterol in pyridine solution in thepresence of sensitisers such as haematoporphyrin and Rose Bengal 36 givesHO 03 H 6the A6-5-hydroperoxide (50), proof of the structure of which rests on itsconversion into the known 37 cholest-6-ene-3P : 5a-diol.Cholesterol reacts with periodic acid to yield cholestane-3p : 501 : 6P-trio1and 38 : 5a-dihydroxycholestan-6-one (52).The reaction is presumed to gothrough the intermediate a-oxide which (a) under the influence of excess ofacid yields the triol or (b) by attack of periodic acid yields the 6p-periodate(51) which can decompose in the manner shown to give the 6-ketone (52).It is necessary to postulate such a mechanism, since the triol is not oxidisedto the ketone (52) by periodic acid.38Ozonolysis of cholesterol in inert solvents has long been known to givean amorphous ozonide of uncertain composition. Ozonolysis in the presenceof alcohols 39 (ROH), however, yields crystalline compounds formulated as(53).Both the amorphous ozonide and the crystalline products are reducedto the 5 : 6-secocholestane-3p : 5 : 6-triol (54) by lithium aluminium hydride.Molecular rearrangements. Further examples of the Wagner-Meerweinrearrangements of 17a-alcohols and 16a : 17a-epoxides have been reported,*Oand the reactions occurring may be rationalised as follows. Under theinfluence of acid, the 17-hydroxyl group is removed or the epoxide ringopened, to give the cation (57; R' = H and OH respectively).This isfollowed by migration of the 13P-methyl group to the 17p-position (the group35 L. F. Fieser, W-Y. Huang, and B. K. Bhattacharyya, J . Org. Chem., 1957,22,1380.36 G. 0. Schenck, K. Gollnick, and A. 0. Neumiiller, Annulen, 1957, 603, 46.37 H. B. Henbest and E. R. H. Jones, J., 1948, 1792.3* R. P. Graber, C . S. Snoddy, jun., H. B. Arnold, and N. L. Wendler, J . Org. Chem.,1956, 21, 1517.SB H. LettrC and A. Jahn, Annalen, 1957, 608, 43; Agigew. Claem., 1957, 69, 266;cf. H. Lettr6 and D. Hotz, ibid., p. 267.40 (a) 0. S. Madayeva and Yu. N. Sheinker, Zhur. obshchei Khim., 1956, 26. 2937,3198, 3201; ( b ) B. Camerino and A. Vercellone, Gazzettu, 1956, 86, 260, 1219; (c) H.L.Herzog, C . C . Joyner, M. J. Gentles, H. T. Hughes, E. P. Oliveto, E. B. Hershberg,and D. H. R. Barton, J . Org. Chem., 1957, 22, 1413; ( d ) K. Heusler and A. Wettstein,Chew. Ber., 1954, 87, 1301268 ORGANIC CHEMISTRY.R adopting the a-configuration) (58). According to Herzog and his col-leagues4OC in the particular case they dealt with (55; A/B-cZ'S, 301 : 11s : 2Op-triacetoxy), subsequent loss of a proton occurs from position 12 to give aMe12 : 13-double bond (cf. 59), in agreement with the formulation proposed byMadayeva for the compounds she was studying. The alternative, of lossof a proton from position 14 with consequent formation of the A13-structure(60), was discounted by nuclear magnetic resonance evidence. Earlierworkers had favoured this alternative structure (60) but had put forwardno evidence for it.It is worth noting that this type of rearrangement occurswith steroids unsubstituted at 11 or having an 11Q-hydroxyl group; anll-0x0 group inhibits the reaction.40cApplications of the Favorski reaction to 2a-bromocholestan-3-one (61),to 4 p-bromocoprost an-3-one 41 (U), and to 3 p-acet ox y-17 or-bromo-2 1 -iodo-pregn-5-en-20-one 42 (69) are illustrated in the accompanying formulae. TheReagents: I , OMe-. 2, Barbier-Wieland degradation. 3, OH-.structures assigned to the two acids (70) and (71) are based on the lowerintensity of light absorption in the ultraviolet region shown by the acid (71),41 D. El Evans, A. C. de Paulet, C. W. Shoppee, and F.Winternitz, J., 1957, 1451..43 J. Romo and A. Romo de Vivar, J. Amer. Chem. Soc., 1057,79, 1118BLADON : STEROIDS. 269presumably owing to inhibition of resonance by the interaction of thecarboxyl and the 13-methyl group.Beckmann rearrangement of the oximes of 17a-hydroxy-20-oxo-steroidsaffords 17-ketones 43 (cf. the similar transformation of oximes of A1s-20-0x0-steroids 44).Prednisone acetate on irradiation with ultraviolet light undergoes theinteresting rearrangement (72 __t 73) .45The structure of the products of the anthrasteroid rearrangement hasbeen shown to be (73a).450( 7 3'),OAc '1.Sterol side chain. A new method for the degradation of the stigmasterolside chain has been disc20sed.~~ 3~-Acetoxy-5a-chlorobisnorcholanaldehyde(74) was converted into a compound with the 17a-hydroxy-20-oxo-side chainby a series of reactions (74 _t 77).An unsaturated aldehyde similar t o (75)&CHO&{fi0 {5 O.CHO {fl"L L( 7 5 ) ( 7 6 ) ( 7 7 )Cl ( 7 4 )Reagents: Br,-CHCI,; H*CO*NMe,. 2, Perphthalic acid. 3, OW.has been converted into a 17-ketone by ozonolysis of the derived cyano-h y drin .4The synthesis of 24-methylenecholesterol from 24-oxocholesterol andmethylenetriphenylphosphorane has been reported by two groups.48Bergmann and Dusza 48e conclude that chalinasterol (from sea anemones)and ostreasterol (from oysters) which were previously known to be identical(and had been assigned the structure 24a-ethylcholesta-5 : 22-dien-3p-01 49),are in fact 24-methylenecholesterol (cf.ref. 48c). Idler and Fagerlund 48bhave also applied the Wittig reaction to the preparation of cholesta-43 J. Schmidt-ThomC, Annalen, 1957. 608, 43.44 E. Testa and F. Faua, Gazzetta, 1957, 87, 971; cf. Ann. Re$orts, 1956, 53, 222.45 D. H. R. Barton and W. C . Taylor, Proc. Chem. SOC., 1957, 147.45a A. W. Burgstahler, J. Amer. Chem. SOC., 1957, 79, 6047; cf. Ann. Re$orts, 1955,46 E. M. Chamberlin, E. Tristram, T. Utne, and J. M. Chemerda, J . Amer. Chem.4 7 R. L. Pederson, J. L. Johnson, R. P. Holysz, and A. C. Ott, ibid., p. 1115.4 8 (a) W. Bergmann and J. P. Dusza, Annalen, 1957, 603, 36; (b) D. R. Idler andU. H. M. Fagerlund, J . Amer. Chem. SOC., 1957, 79, 1988; (c) idem, Chem. and Ind.,.1957. 432.49 W. Bergmann and E. 11. Low, J .Org. Chem., 1947, 12, 67.52, 214.SOC., 1957, 79, 456270 ORGANIC CHEMISTKY.5 : 25-dien-3P-01 from 25-oxo-26-norcholesterol. The product differs from thesubstance previously assigned this structure 50 (formed by dehydration of a25-hydroxy-compound), which therefore must be 24-dehydrocholesterol.Bile acids. A series of three papers 51 describes the synthesis of a largenumber of bile acid derivatives, for possible use as serum-flocculating agents.Two new bile acids (“ Acid I ” and “ Acid I1 ”), isolated from the bile ofrats and pigs,52a have been shown to be respectively 3a : 6a : 7p- and3a : 6P : 7a-trihydroxycholanic Work on the related hyocholicacid and hyodeoxycholic acid has been reported.53The two stereoisomeric (at-position 25) 3a : 7a : 12a-trihydroxycoprostanicacids (81) have been synthesised.% The sodium salts of cholic acid (78) andmethyl hydrogen D- or L-a-methylglutarate (79) were electrolysed together.The additional carbon atom in the product (80) was removed by the Barbier-Wieland method.Vitamins D and Related Compounds.-The first partial synthesis ofcalciferol(85a) from the aldehyde (82) has been announced by Harrison andL y t h g ~ e .~ ~ It was carried through stages (83- 85) withmixtures of stereo-isomers which were separated after the last stage (as 3 : 5-dinitrobenzoates)into calciferol (85a) and eeicalciferol (85b), which was the major componentand was previously unknown. These workers questioned the validity ofthe earlier synthesis claimed by Inhoff en and his colleagues.56 The isomerscalciferol57 (85a), eeicalciferol 55 (85b), and 5 : 6-tra~zs-eeicalciferol 56 (87) allgive the same ketone (86) on Oppenauer oxidation. Inhoffen has alsoreviewed earlier work on partial synthesis of vitamins D.5850 A. I. Ryer, W. H. Gebert, and N. M. Murrill, J . Amer. Chem. Soc., 1950,72,4247;W. G. Dauben and H. L. Bradlow, ibid., p. 4248.51 F. C. Chang, R. T. Blickenstaff, A. Feldstein, J. R. Gray, G. S. McCaleb, andD. H. Sprunt, J . Amer. Chem. SOC., 1950, 72, 2161, 2164; F. C. Chang, A. Feldstein,J . R. Gray, G. S. McCaleb, and D. H. Sprunt, ibid., p. 2167.52 (a) J. T. Matschiner, T. A. Mahowald, W. H. Elliott, E. A. Doisy, jun., S. L.Hsia, and E. A. Doisy, J . Biol. Chem., 1957,225, 771 ; T. A. Mahowald, J.T. Matschiner,S. L. Hsia, R. Richter, E. A. Doisy, jun., W. H. Elliott, and E. A. Doisy, ibid., p. 781;( b ) S. L. Hsia, J. T. Matschiner, T. A. Mahowald, W. H. Elliott, E. A. Doisy, jun.,S. A. Thayer, and E. A. Doisy, ibid., p. 811; (c) idem, ibid., 1957, 226, 667.53 P. Ziegler, Canad. J . Chem., 1956, 34, 1528; A. Corbellini and G. Nathansohn,Gazzetta, 1956, 86, 1240.54 R. J. Bridgwater, Biochem. J., 1956, 64, 593.5 5 I. T. Hamson and B. Lythgoe, Proc. Chem. SOC., 1957, 261.5 6 H. H. Inhoffen, J. Kath, W. Sticherling, and K. Briickner, Annulen, 1957, 603,67 S. Trippett, J.. 195g: 370.Festschrift Arthur Stoll,,” Verlag Birkhauser, Basle, 1957,25.H. H. Inhoffen, inp. 419BLADON STEROIDS. 271By a similar series of reactions, the derivative of cholestanone (88) hasbeen converted into the analogue of calciferol (89) which is biologicallyactive.59R ROHC P ( 8 2 )epi-5:6-trons-V i t a m i n D/4,(85a(85bHOI ) 6-OH) a - O H(cis) Vitamin D and EpimerR = CsH1,. Reagents: I, 4-Acetoxycyc/ohexanone. 2, Ultraviolet light. 3, Ph,P=CHp,4, Oppenauer oxidation.Reagents : I , 4-Met hoxycyclo hexanone-NaOH. 2, Ph,P = CH 2 aMe / MeOHPre-vitamin DPrecalciferolR= C9H17iroTachyrterol isovitamin Di s o Calci fer o lTach y s t e r olAgreement seems to have been reached among the various groups ofworkers as to the formulz. of the B-seco-isomers of the vitamins D. Thestructures and preferred conformations (85, 87,90-93) are those put forwardb9 N. A. Milas and C.Priesing, J . Amer. Chem. Soc., 1957, 79, 3610272 ORGANIC CHEMISTRY.by Havinga and his co-workersJ60 on the basis of spectroscopic results andstudies of the reactivity of the compounds towards maleic anhydride(cf. refs. 58, 61). The structures suggested for the dihydrovitamin anddihydrotachysterol isomersEvidence has been produced 63 which leads to the formulze (94) and (95)for pho t oisop yrocalcif erol and pho t op yrocalci f erol respectively .seem to be less certain.R RSteroid Sapogenins-Much interest has centred on m~cogenin.~~ Thehydroxyl group previously thought to be at position 19 is now known to beat position 1, and has been assigned the P-configuration, largely on the basisof molecular-rotation data 65 and the degradation 66 to the known 67androst-5-ene-1 p : 3(3 : 17p-tri01.~~ Ruscogenin is usually contaminated byan isomer, neorus~ogenin.~~ Oxidation of pseudoruscogenin and pseudoneo-ruscogenin led to (-)- and (+)-=-methylglutark acid respectively.69bMeHHORuscogenin is therefore 22a : 25~-spirost-5-en-lp : Sp-diol (96; R = Me,R = H), and neoruscogenin is the corresponding 25~-isomer (96; R = H,R' = Me).Willagenin,'O a new sapogenin from Yucca$Zilifera, has been shown to be12-oxosarsasapogenin (97).6o A.Verloop, A. L. Koevoet, and E. Havinga, Rec. Trav. chim., 1957, 76, 689; cf.references 58 and 61.61 L. Velluz, G. Amiard, and B. Goffinet, Compt. rend., 1955, 240, 2076, 2156,2326; Bull. Soc. chim. France, 1955, 1341.62 P. Westerhof and J. A. K. Buisman, Rec.Trav. chim., 1956, 75, 453; 1957, 76,679; J. L. J. van de Vliervoet, P. Westerhof, J. A. K. Buisman, and E. Havinga, ibid.,1956, 75, 1179; F. van Werder, Naturwiss., 1956, 43, 380; Annalen, 1957, 603, 15.65 W. G. Dauben and G. J. Fonken, J . Amer. Chem. Soc., 1957, 79, 2971.1 3 ~ Cf. Ann. Reports.. 1955, 52, 223.6 s H. Lapin, Compt. rend., 1957, 244, 3065.e6 W. R. Benn, F. Colton, and R. Pappo, J . Amer. Chem. Soc., 1957, 79, 3920.13' R. M. Dodson, A. H. Goldkamp, and R. D. Muir, ibid., p. 3921.a Cf. A. L. Nussbaum, F. E. Carlon, D. Gould, E. P. Oliveto, E. B. Hershberg,6s ( a ) D. Burn, B. Ellis, and V. Petrow, Proc. Chem. Soc., 1957, 119; (b) C. Sanni67 O H. E. Kenney and M. E. Wall, J . Org. Chem., 1957, 22, 468.M. L. Gilmore, and W.Charney, ibid., p. 4814.and H. Lapin, Bull. Soc. chim. France, 1957, 1237BLADON : STEROIDS. 273The oxidation of cyclopseudotigogenin (20-isotigogenin) (98) was shownto give a 20~-hydroxy-derivative (99). The tertiary character of thehydroxyl group follows from its resistance to oxidising and acetylating42-( 9 8 )TS f p-C&i.+Me-S02 0(103) (102)Reagents: I , Cr0,-AcOH. 2, SOCl,pyridine. 3, 0 5 0 , . 4, H2-Pt-AcOH. 5, HIO,.6, 0,. 7, p-C,H,Me*SO,CI. 8, LIAIH,.agents, and its position is made certain by the transformations outlined inthe f0rmula2.~~ The similarity of the infrared spectrum of compound (100)to that of tigogenin acetate is cited as evidence that (in the 25~-series) thesole difference between the sapogenins and the cyclopseudosapogenins is theconfiguration of the 20-methyl group.That this conclusion is not acceptedby all workers is implied in the nomenclature scheme proposed by R ~ s e n . ~ ~The scheme can be criticised as not conforming to the accepted usages[e.g., the cyclopseudosapogenins are called 21-p(sic) -sapogenins] .Wall and his co-workers have reported studies on the isomeric 23-bromo-derivatives of diosgenin and tigogenin, 73 on gentrogenin (12-oxodiosgenin),and on correllogenin (12-0xoyarnogenin),~* as well as on the conversion ofgentrogenin into 3p-acetoxy-17~+hydroxypregn-5-ene-12 : 20-dione 75 andinto 1 l-oxodiosgenin.76Steroid Alkaloids.-A second elegant correlation of the alkaloidstomatidine and solasodine with the sapogenins neotigogenin and tigogeninrespectively has been reported. The N-acetyl derivatives of the dihydro-alkaloids were converted into the N-nitroso-compounds and thence, bythermal decomposition and hydrolysis, into the dihydrosapogenins.Theoccurrence together in Solanum tzlberoszkm of tomatid-5-en01 and the corres-ponding sapogenin, yamogenin, is of interest.7871 M. E. Wall and H. A. Walens, Chem. and Ind., 1957, 818.72 W. E. Rosen, ibid., p. 703.73 M. E. Wall and H. W. Jones, J . Amev. Chem. SOC., 1957, 79, 3222.74 H. A. Walens, S. Serota, and M. E. Wall, J . Org. Chem., 1957, 22, 182.76 E. S. Rothman and M. E. Wall, ibid., p. 223.76 Idem, J . Amer. Chem. Soc.. 1957, 79, 3228.77 Y . Sat0 and H. G. Latham, jun., J . Org. Chern., 1957, 22, 981; Y.Sato, H. G.Latham, jun., L. H. Briggs, and R. N. Seelye, J . Amer. Clzem. Soc.. 1957, 79, 6089;cf. Ann. Reports, 1956, 53, 226.78 K. Schreiber, Angew. Chem., 1957, 69, 483274 0 KG AN IC C H E bl 1 STH 1’.The glycosidic alkaloid, tomatine, forms an insoluble molecular complexwith cholesterol and other sterols, and has been suggested as an (expensive)alternative to digitonin as an analytical reagent.79The chemistry of jervine and veratramine has been reviewed.sOAttention is drawn to a review 81 of cardiac aglycones.Total Synthesis.-This subject was not dealt with in last year’s Report,and so work disclosed in the two years 1956 and 1957 is recorded here. Ofgreat interest is the monumental series of papers 82s83 detailing the work ofJohnson and his colleagues on the “ hydrochrysene ” approach.Most ofthe important results had been announced in preliminary communications.A modification of this synthesis which allows of more stereochemical controlin the introduction of the 13-methyl group involves the use of intermediateshaving a 9 : ll-double bond, the presence of which has a profound influenceon the stereochemistry of the cyclisation step. 83a Experiments on bicyclicmodels also suggested an adaptation to the synthesis of 18-oxygenatedsteroids. B bThe first stages of a modification of the Cornforth-Robinson synthesis,in which an extra oxygen function (at position 11) is present throughout,have been detailed by a second group of workers at the Merck laboratories.MA new synthesis starting from 6-methoxy-l-tetralone (104) (the B-c ring7Q G.Schulz and H. Sander, 2. fihysiol. Chem., 1957, 308, 122.8 0 0. Wintersteiner, in “ Festschrift Arthur Stoll,” Verlag Birkhauser, Basle, 1957,p. 166.C. Tamm, Fortschr. Chem. org. Naturstoffe, 1956, 13, 137.82 W. S. Johnson, J . Amer. Chem. Soc., 1956, 78, 6278; W. S. Johnson, J .Szmuszkovicz, E. R. Rogier, H. I. Hadler, and H. Wynberg, ibid., p. 6285; W. S.Johnson, E. R. Rogier, J. Szmuszkovicz, H. I. Hadler, J. Ackerman, B. K. Bhatta-charyya, B. M. Bloom, L. Stalmann, R. A. Clement, B. Bannister, and H. Wynberg,ibid., 6289; W. S . Johnson, J. Ackerman, J. F. Eastham, and H. A. DeWalt, jun.,ibid., 6302; W. S. Johnson, A. D. Kemp, R. Pappo, J. Ackerman, and W. F. Johns,ibid., 6312; W. S.Johnson, E. R. Rogier, and J. Ackerman, ibid., 6322; W. S. Johnson,B. Bannister, and R. Pappo, ibid., 6331; W. S. Johnson, R. Pappo, and W. F. Johns,ibid., 6339; R. Pappo, €3. M. Bloom, and W. S. Johnson, ibid., 6347; W. S. Johnson,B. Bannister, R. Pappo, and J. E. Pike, ibid., 6354.8s ( a ) W. S. Johnson and D. S. Allen, jun., ibid., 1957, 79, 1261; ( b ) W. S. Johnson,D. G. Martin, R. Pappo, S. D. Darling, and R. A. Clement, Proc. Chem. Soc., 1957, 58.84 W. F. Newhall, S . A. Hams, F. W. Holly, E. L. Johnston, J . W. Richter, E.Walton, A. N. Wilson, and K. Folkers, J . Amer. Chem. Soc., 1955, 77, 5646; E.Walton, A. N. Wilson, A. C. Haven, jun., C. H. Hoffman, E. L. Johnston, W. F.Newhall, F. N. Robinson, and F. W. Holly, ibid., 1956, 78, 4760BLADON STEROIDS.275moiety) has been described by Stork and his colleague^.^^ Ring D (six-membered) is introduced first, followed by ring A. The essential steps areshown in formulz (104 __t 109). The final product (109) is identical with acompound which has already been converted into cortisone.86 A similarapproach was also envisaged by M. J. T. Robinson 87 who arranged that the10-methyl group was present throughout.Details have appeared of the first total synthesis of aldosterone,*& andof a second synthesis following a somewhat similar approach,Sa both beingpart of a collaborative effort involving four laboratories.88cSteroid Biogenesis.-The discovery,sg that B-hydroxy-(3-methyl-&valero-lactone (110) (or the corresponding acid) is able to replace acetate in thesynthesis of squalene and cholesterol by rat-liver homogenate, has attractedmuch attention.g0 The yield of cholesterol from the lactone (110) is muchhigher than from other compounds (e.g., P-methylcrotonic acid andp-hydroxy-(3-methylglutaric acid) which have been postulated as inter-mediates in the acetate __t cholesterol pathway.Perhaps these other com-pounds are on an alternative route.g0dWhen the [2-14C]lactone (110) is transformed into squalene (lll), all theradioactivity appears 90a in the carbon atoms marked *. Further, incholesterol biosynthesised from similarly labelled material,g0e the radio-activity was detected in C(,) and (&, and in one of the terminal methylgroups of the side chain; it was absent from carbon at positions 20, 21, 23,24, and 25, and from the other terminal methyl group. From these resultsit can be concluded that the (head-to-tail) sequence of isoprene units isformed by condensation of the hydroxymethyl group of one molecule ofp6-dihydroxy-p-methylvaleric acid with the methylene group adjacent tothe carboxyl group in the next molecule.All the carboxyl groups areeliminated at some stage for, with carboxyl-labelled acid, no radioactivity isincorporated into cholesterol, but it is recovered as carbon dioxide. E9bThe conversion of lanosterol into cholesterol probably involves at leasttwo intermediates. The first is possibly a 4 : 4-dimethylcholestadienol (one85 G. Stork, H. J. E. Loewenthal, and P. C. Mukharji, J . Amer.Chem. Soc., 1956,a6 L. B. Barkley, M. W. Farrar, W. S. Knowles, H. Raffelson, and Q. E. Thompson,M. J. T. Robinson, Tetrahedron, 1957, 1, 49.88 ( a ) J. Schmidlin, G. Anner, J. R. Billeter, K. Heusler, H. Uebenvasser, P.Wieland, and A. Wettstein, Helv. Chim. Ada, 1957, 40, 1034, 1438, 2291; ( b ) A.Lardon, 0. Schindler, and T. Reichstein, ibid., p. 666; ( c ) cf. S. A. Szpilfogel, W. J.van der Burg, C. M. Siegmann, and D. A. van Dorp, Rec. Trav. chim., 1956, 75, 1043.(a) P. A. Tavormina, M. H. Gibbs, and J. W. Huff, J . Amer. Chem. SOL, 1956,78, 4498; ( b ) P. A. Tavormina and M. H. Gibbs, ibid., p. 6210.9~ ( a ) J. W. Cornforth, R. H. Cornforth, G. PopjBk, and I. Youhotsky-Gore,Biochem. J., 1957, 66, 10 P; ( b ) R. G. Gould and G. PopjAk, ibid., p.51 P; (c) D. L.,Azarnoff and G. L. Curran, J . Amer. Chem. Soc., 1957, 79, 2968; (d) cf. K. F. Gey,A. Pletscher, 0. Isler, R. Ruegg. and J. Wursch, Helv. Chim. Acla, 1957, 40, 2354;le) 0, Isler, J. Wiirsch, K. F. Gey, and A. Pletscher, ibid., p- 2369.78, 502.ibid., 1954, 76, 6014, 5017276 ORGANIC CHEMISTRY.double bond at position 24 : 25; another in the region of the B/C ringjunction) 01 and the second is probably zymosterol.92The details of the chemical degradation of cholesterol biosynthesisedfrom labelled acetate has appeared.93 With this, the biogenetic origin of allthe carbon atoms in cholesterol is known.It has been established that the 28-carbon atom of ergosterol (andeburicoic acid) is biosynthesised from f ~ r r n a t e .~ ~ Methionine is an inter-mediate and it appears that the methyl group in methionine is transferredintact to position 24 of the steroid side chain.Q5P. B.11. AMINO-ACIDS, PEPTIDES, AM) PROTEINS.THE two years since the last Report under this title 1 have seen remarkableprogress in the elucidation of the structures of natural peptides and proteinsand in the synthesis of peptides, and an attempt to give an adequate pictureof the achievements in these directions has left little space to devote towork on amino-acids, where development has chiefly been along establishedlines.those acids newly identified include 1-aminocyclopropane-1-carboxylic acid,spy-dihydroxyglutamic acid,* and S-methyl-~-cysteine,~ whose sulphoxide haspreviously been reported.It is interesting to note here that y-glutamyl-S-methylcysteine and its sulphoxide have also been found.g Timely warningshave been given of the danger of error in identifying amino-acids by paperchromatography alone. Homoserine and threonine have identical RP valuesin 5 out of 7 solvent systems investigated; Synge and Wood have pointedout that a change in chromatographic pattern after acid treatment is notalways due to the presence of a peptide,S whilst a mixture of eleven peptidesobtained from an aqueous extract of raw wool gave, both before and afteracid hydrolysis, two-dimensional chromatograms very similar to each otherand to that from a mixture of arnino-acid~.~Amino-acids.-Useful reviews of natural amino-acids have appeared;91 P.B. Schneider, R. €3. Clayton, and K. Bloch, J . Biol. Chem., 1957, 224, 175;9% J. D. Johnston and K. Bloch, ibid., 1957, 79, 1145.93 J. W. Cornforth, I. Y. Gore, and G. PopjAk, Biochem. J., 1957, 65, 94.94 H. Danielsson and K. Bloch, J . Amer. Chem. Soc., 1957, 79, 500; W. G. Dauben.G. J. Fonken, and G. A. Boswell, ibid., p. 1000.95 G. J. Alexander, A. M. Gold, and E. Schwenk. ibid., p. 2967; G. J. Alexanderand E. Schwenk, ibid., p. 4554.1 Ann. Reports, 1955, 52, 271.2 ( a ) F. C . Steward, R. M. Zacharius, and J. K. Pollard, Ann. Acad. Sci. Fenn., 1955,AII, 60, 321; (b) Festschrift Prof. Dr. Arthur Stoll, Birkhauser, Basel, 1957, p. 565;(c) H. Musso, Angew. Chem., 1956, 88, 313.3 L. F. Burroughs, Nature, 1957, 179, 360; M.-L. Vahatalo and A.I. Virtanen,Actu Chem. Scand., 1957, 11, 741.4 A. I. Virtanen and T. Ettala, ibid., p. 182.5 J. I?. Thompson, C. J. Morris, and R. M. Zacharius, Nature. 1956, 178, 593;J. B. Ragland and J. E. Liverman, Arch. Biochem. Siophys., 1956, 65, 574.7 J. A. Bakhuis, Nature, 1957, 180, 713.8 R. L. Synge and J. C. Wood, Biochem. J., 1956, 84, 252.9 K. R. Deane and E, V. Truter, Biochim. Biophys. Acta, 1955, 18, 435.F. Gautschi and K. Bloch, J . Amer. Chem. SOC., 1957, 79, 684.H. Rinderknecht, Chem. and Ind., 1967, 1384YOUNG : AMINO-ACIDS, PEPTIDES, AbiD PROTEINS. 277y- and 6-Aminovaleric acid have been synthesised by a route which maybe convenient for analogous amino-acids (not a) : loA simple synthesis of y-hydroxyproline (1) and y-allohydroxyproline (2)starts from the d y l derivative of acetamidomalonic ester.ll The diastereo-isomers were separated as their copper salts.In a series of investigationsof the stereochemistry of y-hydroxyproline and its derivatives, Witkop l2 has6;HO ( 1 )tested the validity of Hudson’s lactone rule for y- and 8-hydroxyamirlo-acids;the formation of a lactone from benzyloxycarbonyl-y-aZZohydroxy-L-proline(3) requires the stereochemistry of a D-sugar at C(,,, and in agreement with0-coDGHCSZO t= Ph.CHs*O*CO DG and LS relate the configuration to thatof D-glyceraldehyde and of I.-serine re-spectively.the rule the ladone has a-more positive specific rotation than the acid.An anomaly appeared in the case of the y-hydroxyornithine derivative (4),when pyridine was used as the solvent for the lactone, but in dimethylC ~ H I I .CO*NH*HzC c4° COiHL S C ~ H I ~ - C O .N ~ - $ ~ ~ H2i$L H L sH DG HO H LG HCH~.NH.CO*C~HII CHZ’NH2DG( 4 )( 5 )sulphoxide the rule was obeyed. On the basis of this rule, the erythro-configuration (5) is provisionally assigned to the 8-hydroxy-L-lysine derivedfrom collagen.lo Ng. Ph. Buu-Hoi and M. Sy, Cornpt. rend., 1966, 242, 2011.l2 B. Witkop, Ezpevientia, 1956, 12, 372.T. Wieland and U. Wintermeyer, Chem. Ber., 1957, 90, 1721278 ORGANIC CHEMISTRY.An interesting example of the direct resolution of a-amino-acids byl1 entrainment ” has been repo~3ed.l~ Crystallisation of DL-threonine towhich D-threonine had been added brought down the D-isomer in amountapproximately twice the weight added; a second crystallisation after theaddition of more racemate gave L-isomer, and after 10 such cycles two-thirdsof the racemate had been resolved, a final crystallisation giving opticallypure enantiomorphs.The purification of amino-mercapto-acids and -peptides is often effectedthrough insoluble metal mercaptides, but the regeneration of the thiol byhydrogen sulphide is tedious and not always satisfactory.An attractivealternative has been developed l4 in which mercury mercaptides are reducedquantitatively by electrolysis at a mercury cathode, in an apparatus of thetype used for the electrolytic removal of salts. For the regeneration ofpapain from its mercury derivative, E. L. Smith et aZ.15 recommend aninteresting procedure developed by Dintzis,lG in which thioglycollate isbound to a strong anion-exchange resin, which will then liberate thiols fromtheir mercapt ides.An unexpected observation is that when heated in phosphate buffer atpH 6.7 asparagine forms the p-lactam of aspartic acid (4-carboxy-2-azetidin-one) in 6 5 % yie1d.l’ The lactam was stable to boiling G~-hydrochloricacid and to @4~-barium hydroxide at room temperature.The reducedform of the lactam, azetidine-2-carboxylic acid, occurs naturally.18Purification of Peptides and Proteins.-Authoritative reviews of columnchromatography l9 and of counter-current distribution 2o have appeared.One of the most important developments in the separation of peptides hasbeen the use of sulphonated polystyrene cation-exchange resins with a lowdegree of cross-linking, to increase the effective surface area; thus, styreneco-polymerised with 2% of divinylbenzene (Dowex 50-X2) separated a seriesof peptides containing between 2 and 24 residues, obtained by tryptichydrolysis of oxidized ribonuclease.21 The effectiveness of the resolution isshown by the fact that two peptides, of 20 and 24 residues respectively,crystallised from their fractions.High-voltage electrophoresis on paper, inthe apparatus devised by Mich1,22 has proved to be a method with comparableresolving power, although the amounts separable are smaller ; the commercialavailability of apparatus for continuous paper electrophoresis will greatlyincrease the usefulness of this procedure.An interesting technique is the useof sponge rubber as the support in zone electroph~resis,~~ recovery of thematerial in each zone being simple and nearly quantitative. A modifiedstarch gel has been used as the supporting medium in the zone electrophoresisl3 G. Amiard, Bull, SOC. chim. France, 1956, 447.l* R. E. Benesch and R. Benesch, Biochim. Biophys. Actu, 1957, 23, 658.E. L. Smith, B. J . Finkle, and A. Stockell, Discuss. Faraduy SOL, 1955, 20, 96.€3. M. Dintzis, Thesis, Harvard, 1952.l7 E. A.Talley, T. J . Fitzpatrick, and W. L. Porter, J. Amer. Clzem. Soc., 1956,78,5836.l8 L. Fowden, Nature, 1955, 176, 347.l9 S. Moore and W. H. Stein, Adv. Protein Chem., 1956, 11, 191.2o P. von Tavel and R. Signer, ibid., p. 237.21 C.H. W. Hirs, W. H. Stein, and S. Moore, J. Biol. Chenz., 1956, 219, 623.22 H. Michl, Sitzungsber. osterr. Ahad. Wiss., Abt. 11, 1951, 160, 489.23 H. K. Mitchell and L. A. Herzenberg, Anulyt. Chew., 1957, 29, 1229YOUNG : AMINO-ACIDS, PEPTIDES, AND PROTEINS. 279of plasma proteins; the low solid content (<$yo) of the gel ensures a freerpath for migration than when solid fillers are used, and electro-osmosis isnegligible.% Zone electrophoresis on vertical columns of powdered cellulosehas been used to fractionate substances of both low and high molecularweight, in quantities up to 100 g., and the fractionation of serum proteins inthis way has recently been described.25 The chromatography of proteinspresents a complicated problem, since penetration into the adsorbent isdifficult , configurational changes may occur during adsorption and desorp-tion, and the multivalent nature of the molecule is likely to make elutiondepend critically on the composition of the eluent.The polymethacrylicacid cation exchanger Amberlite IRC-50 proved invaluable for the puri-fication of basic proteins of low molecular weight , such as ribonuclease,lysozyme , chymotrypsin , and chymotrypsinogen, and the anion-exchangeresin Dowex-2 (a quaternary ammonium base on a polystyrene skeleton) hasbeen used for the fractionation of several proteinsJ26 but a technique whichmay prove more generally applicable to proteins of higher molecular weightuses modified celluloses , such as carboxymethyl- and diethylaminoethyl-cellulose.These are cation- and anion-exchangers respectively, of highcapacity, and the latter has been used successfully for the fractionation ofserum proteins.27Structural Investigation of Peptides and Proteins.-The elucidation of thestructure of insulin28 has been followed by remarkable progress in the in-vestigation of natural peptides and proteins, using chiefly methods developedearlier. Sanger’s dinitrophenylation and Edman’s thiohydantoin procedureshave so far proved the most valuable for the identification of the N-terminalresidues; the latter procedure has been used, stepwise, to reveal the firstseven residues of a-corticotr~pin.~~ Edman 30 has shown that this degrad-ation proceeds through an intermediate 2-anilino-5-thiazolinone (6) , whichrearranges to the 3-phenyl-2-thiohydantoin (7).Ph.NH. CS. NH . CHR’. CO*NH.CHR“. CO2H Ph*NH*C-i a Ph.N-CSII OC, I I ,NHHN: ,COCHR’ ( 6 ) CHR’+ + N H 3 - C H R ” - C O x HtfSlowPh*NH*CS-NHA third and most promising method uses leucine aminopeptidase toremove N-terminal residues; 31 its action is far less specific than its nameindicates, and Hill and Smith32 have shown that it will remove in turnsome 120 N-terminal residues from the chain of 180 residues in mercuripapain24 P. Bernfeld and J. S. Nisselbaum, J . Bid. Chem., 1956, 220, 851.25 H. I. Gedin and J. Porath, Biochim. Biophys. Acta, 1957, 26, 159.26 H. G. Boman and L. E. Westlund, Arch. Biochem. Biophys., 1956, 64, 217.27 E. A. Peterson and H. A. Sober, J . Amer. Chem.Soc., 1956, 78, 751; H. A. Sober,28 Review: F. Sanger and L. F. Smith, Endeavour, 1957, 16, 48.29 J. I. Hams and C . H. Li, J . Amer. Chem. SOC., 1954, 76, 3607.31 R. L. Hill and E. L. Smith, J . BioZ. Chem., 1957, 228, 577.32 Idem, Biochim. Biophys. Acta, 1956, 19, 376.F. J. Gutter, M. M. Wyckoff, and E. A. Peterson, ibid., p. 756.P. Edman, Acta Chem. Scund., 1956, 10, 761280 ORGANIC CHEMISTRY.(and the regenerated peptide is still enzymically active towards benzoyl-L-arginine amide). For the identification of C-terminal residues, the use ofcarboxypeptidase 33 and cleavage by hydrazine 34 have been preferred.Determination of the sequence of amino-acids within the chain requiresfission into fragments which can then be separated and investigated in-dividually.Partial acid hydrolysis may provide useful frzpents, but oftenthe mixture obtained is undesirably complex. Experience has shown thatthe risk of transpeptidation during enzymic hydrolysis is more remote thanhad been supposed, and in recent work trypsin, chymotrypsin, and pepsinhave yielded the most valuable degradation products. A useful additon tothis list is the bacterial enzyme subtilisin, which has a wide range of activity,and it was used advantageously in the elucidation of the structure ofg l u ~ a g o n . ~ ~ Quantitative separation of the fragments has been greatlyfacilitated by the availability of the ion-exchange resins mentioned above,and extensive use has been made of counter-current extraction and ofMichl's high-voltage paper electrophoresis apparatus.22Two interesting attempts to control enzymic attack in order to yieldfragments of useful size deserve mention.Introduction of a dinitrophenylor (preferably) benzyloxycarbonyl group on the c-amino-group of a lysineresidue renders it immune to attack by trypsin, which then cleaves onlyarginylamino-linkages. Oxidized ribonuclease, for example, gave theexpected five peptides, which were readily separated by paper electro-p h ~ r e s i s . ~ ~ The second approach is so far tentative; the aim is to modifythe side chains of cysteine residues in the protein by reaction with 2-bromo-ethylamine, forming S-2-aminoethyl derivatives, in the expectation that thecysteinyl linkages will become susceptible to attack by trypsin, since theside chain closely resembles that of lysine.It has been shown that po1y-S-2-aminoethylcysteine is an excellent substrate for tryp~in,~' and the applic-ation of this ingenious method to a protein is now awaited.The general methods discussed above have been used with outstandingsuccess, particularly in the investigation of peptide enzymes and hormones,and some of the more important structures so revealed will now be given.A substantial portion of the structure of the (bovine) ribonuclease moleculeis already k n 0 ~ n , ~ 1 > ~ 8 ~ from work in the Rockefeller Institute for MedicalResearch, New York, and in the National Institutes of Health, Maryland,and the latest available information 38b is incorporated in structure (8).Thepositions of the disulphide bridges were determined 39 by degradation of the33 J. I. Harris, Chem. SOC. Spec. Pzcbl., No. 2, 1955, p. 71.34 E.g., C.-I. Niu and H. Fraenkel-Conrat, J . Amer. Chem. SOL, 1955, 77, 5882.35 W. W. Bromer, A. Staub, E. R. Diller, H. L. Bird, L. G. Sinn, and 0. K. Behrens,J . Amer. Chem. Soc., 1957, 79, 2794, 2798, 2801, 2805, 2807.313 R. R. Redfield and C. B. Anfinsen, J. B i d . Chem., 1956,221, 385; C. B. Anfinsen,M. Sela, and H. Tritch, Arch. Biochem. Biophys., 1956, 65, 156.37 H. Lindley, Nature, 1956, 178, 647.8 8 ( a ) J. L. Bailey, S. Moore, and W. H. Stein, J . B i d . Chem., 1956, 221, 143; C. H. W.Hirs, W. H. Stein, and S. Moore, ibid., p. 151; R. R. Redfield and C. B. Anfinsen, ibid.,p . 385; C.H. W. Hirs, Fed. Proc., 1957, 16, 196; ( b ) C. H. W. Hirs, W. H. Stein, andS. Moore, Symposium on Protein Chemistry, Paris, July, 1957. The Reporter isgrateful for permission to quote from the Proceedings, to be published by John Wiley.30 A. P. Ryle and C. €3. Anfinsen, Biochirn. Biophys. Acta, 1957, 24, 633; D. H.Spackman, S. Moore, and W. H. Stein, Fed. PYOC., 1957, 16, 252YOUNG AMINO-ACIDS, PEPTIDES, AND PROTEINS. 281enzyme with subtilisin, followed by electrophoretic separation of the cystine-containing fragments; these were oxidised with performic acid, and theresultant peptides of cysteic acid were similarly separated. Comparison ofLys.glu.thr.ala.ala.ala.lys.phe.glu,arg.ser.thr.ser.ser.asp. his.met.glu.ala.ala.ser.ser.asp.ser.tyr.c~s,-INH*(11) Iasp.lu.met.met.lys.ser.arg.asp.leu.thr.lys,asp.arg.(~slas~,v~l,~roltbrllys).phe.( lu,val,leu,ser,his).- 7I I f INH2INH2INH1 I P1HIN NHI(V> 1 (Iv) I (W I (asp glu,ola,vol).(cys,glu,olu,v~l,ser).lys.asp.val.ala.cys.lys.asp.gly.thr.asp. lu.cys.tyr.glu.ser.tyr.ser.-NH, HIN NHS NHI INH*INHI NH,(VII) I (W I thr.met.ser,ileu.thr.asp.cys.arg.glu.ser.thr.ser.gly.lys.tyr.pro.asp.ala.cys,tyr.lys.thr.thr.asp, lu.ala.- I ? H,N NH, INH,(Vlll) I I 24lys.(vol,ileu,,bis).(cys,osp glu,gly,a~o,pro).tyr.(va~~,~ro,his).phe.asp.ala.ser~val. I NHl(8) Ribonuclease 88bThe abbreviations used i n this and other structures are those of E. Brand and J. T. Edsall (Ann.Each amino-acid residue i s joined through i t s carboxyl group t o the Rev.Biochern., 1947, 16,223).residue which follows. 7"' Side-chain amides are indicated thus:NH2The arrangement of residues italicised and enclosed in brackets is not yet known. Romannumerals refer to the half-cystine residues below (see text).the structures of these peptides with the sequences already known establishedthe position of the bridges, between half-cystine residues I-VI, II-VIII,III-VII, and IV-V (see structure 8). It will be seen that the last bridgeinvolves an intra-chain disulphide ring system two residues larger than thatfound in insulin, oxytocin, and the vasopressins, and in order to accommodatethese bridges the protein must assume a closely folded form. The establish-ment of the chemical structure of an enzyme is a landmark which is nowclearly in sight. Considerable progress has been made in the investigation ofthe lysozyme from egg-white,4* pepsin and pepsinogen,*l and papain.42A major portion of the effort in this field has been directed to the study40 R.Acher, U.-R. Laurila, and C. Fromageot, Biochim. Biophys. Acta, 1956, 19,97; J. Thaureaux and R. Acher, ibid., 1956, 20, 559; J. Thaureaux and P. Jollds,Compt. rend., 1956, 243, 1926; P. Joll&s, J. Jollds-Thaureaux, and C. Fromageot,ref. 38 ( b ) .41 H. van Vunakis and R. M. Herriott, Biochim. Biophys. Acta, 1957, 23. 600;K. Heirwegh and P. Edman, ibid., 1957, 24, 219.4z E. L. Smith and J. R. Kimmel, Proc. Internat. Wool Textile Res. Conf., Australia,1955, Vol. C, p. 199282 ORGANIC CHEMISTRY.of peptides with hormonal activity.The structures of the insulins obtainedfrom pig, sheep, horse, and whale have been compared with that fromcattle; 43 the only differences lie within the intra-chain disulphide ring system,as shown in (9). A most notable achievement is the elucidation of the struc-ture of glucagon (10) , the hyperglycaemic-glycogenolytic hormone isolated6 r 7 8 9 1 0 s ~ l l . . . . . . CY.CY.ALA. SER.VAL. cy . . . . . . (cattle) I Sthr.ser.ileu. (pig and whale)thr.gly.ileu. (horse)1ala.gly.val. (sheep)(9) Variations in the disulphide ring system of the A-chain of insulins.The residues printed in small capitals are replaced by those below them.Hisser. lu.gly.thr.phe.thr.ser.asp.tyr.ser.lys.tyr.leu.~p.ser.arg,- B NHa 29arg.ala.glu.asp.phe.val.1u.try.leu.met.asp.thr INHlfNH*INHl( 10) Glucagon20Ser.tyr.ser.rnet.g/u.his.phe.arg.try.gly. lys.pro.va1 .gly.lys.lys.arg,arg.pro.val.lys.val.tyr,pro.-25 26 27 28 29 30 31 32 39ALA.GLY.GLu.AsP.asp.GLU.ALA.sER.g~U.a~a.phe.pro.~eu.giu.phe . . a (I I ) -- (4 (b)(a) asp.gly.ala.glu. (b) lu.leu.ala . . . . . . * B (12) r NH,The sequences o f a - and 8-corticotropin.Two amide groups remain t o be assigned in a-corticotropinI 2 3 4 5 6 7 8 9 1 0 l 1 1 2 1 3a ( I 3) R-ser.tyr.se r.met.glu. his.phe.arg.try.gly. l ys. pro.val .-N HI 2 3 4 5 6 7 8 9 10 II 1213 I4 1516 17 188 (I 4) asp.glu.gly.pro.tyr.lys.met.glu.his.phe.arg.try.gly.ser.pro.pro.1ys.asp.a- and p-Melanocyte-stimulating hormones.from hog pancreas.35 The details of the extensive investigations which led tothe determination of the structure of p-corticotropin (12) (from pigs) haveappeared,a and the complete sequence of the adrenocorticotropic hormone43 J. I.Harris, F. Sanger, and M. A. Naughton, Arch. Biochem. Bioehys., 1956,65,427.44 R. G. Shepherd, K. S. Howard, P. H. Bell, A. R. Cacciola, R. G. Child, M. C .Davies, J. P. English, B. M. Finn, J. H. Meisenhelder, A. W. Moyer, and J. van derScheer, J . Amer. Chem. SOL, 1956,78, 5051; P. H. Bell, K. S. Howard, R. G. Shepherd,B. M. Finn, and J. H. Meisenhelder, ibid., p. 5059; R. G. Shepherd, S. D. Willson,K. S. Howard, P. H. Bell, D. S. Davies, S. B. Davis, E. A. Eigner, and N. E. Shakespeare,ibid., p. 5067; R. A. Brown, M. Davies, M. Englert, and H.R. Cox, ibid., p. 5077YOUNG : AMINO-ACIDS, PEPTIDES, AND PROTEINS. 283from sheep, ct-corticotropin (1 1) , has been reported.45 a-Corticotropin willbe seen to differ from @-corticotropin in residues 25-28 and 31-32; twoamide groups, not yet located, are present in the a-compound. A com-prehensive review of the adrenocorticotropic hormones and of the growthhormone, somatotropin (also found in the anterior pituitary gland), hasappeared; 46 the latter is estimated to have a molecular weight of 45,000,and structural investigations have begun. Two peptide hormones whichstimulate the melanocytes (pigmented cells) and so darken the skin of cold-blooded vertebrates have been isolated from pig pituitary glands, and theamino-acid sequences of both (a- and p-melanocyte-stimulating hormones)have now been elucidated. The a-compound (13) has the sequence of thefirst 13 N-terminal residues of the corticotropins (which have slight melano-cyte-stimulating activity) but the N-terminal serine is acylated by an asyet unidentified group, and the C-terminal valine is in the form of its amide.*’The P-compound (14) 48a has a more distant, yet distinct, resemblance to thefirst portion of the corticotropin structures.The bovine analogue differsonly in the second residue, having serine in place of glutamic It isinteresting that, if the N-terminal serine of p-corticotropin is oxidised byperiodate or removed by alkali, the loss of the adrenocorticotropic hormoneactivity is accompanied by a significant increase in the melanocyte-stimulat-ing activity.The peptide ser.met. lu.his.phe.arg.try.gly, which has the 7 NH2sequence common to the corticotropins and to a- and p-melanocyte-stimulat-ing hormone, has recently been synthesised, and has some melanocyte-stimulating a~tivity.4~Physiological stimuli cause liberation of the enzyme renin from the renalcortex, and by the action of rabbit renin on ox serum Peart 50 isolated adecapeptide, hypertensin-I (ox), which raises the blood pressure in rats andhas been shown 51 to have structure (15). The analogue obtained from horseserum has isoleucine in place of valine in the fifth residue, “ileu5-hyper-tensin-I ” (16),52 and there is evidence that the active entities are in fact theoctapeptides va15- and ileu5-hypertensin-I1 (from ox and horse serumrespectively) resulting from the removal in vivo of the two C-terminalresidues.Val5-hypertensin-I has been ~ynthesised,~~ as have also thebiologically active aspartyl-P-amides of val5- and ileu5-hypertensin-11.45 C. H. Li, I. I. Geschwind, R. D. Cole, I. D. Raaclte, J . I. Harris, and J. S. Dixon,46 C. H. Li, Adv. Protein Ghepn., 1956, 11, 101.47 J . I. Harris and A. B. Lerner, Nature, 1957, 179, 1346.4t3 ( a ) J. I. Harris and P. ROOS, Nature, 1956, 178, 90; I. I. Geschwind: C. H. Li,and L. Barnafi, J. Amer. Chem. SOC., 1956, 78, 4494; 1957, 79, 620; ( b ) adem, abad.,p. 6394.49 K. Hofmann, T. A. Thompson, and E. T. Schwartz, ibid., 1957, 79, 6087.5 0 W. S. Peart, Biochem. J., 1956, 62, 520.51 D.F. Elliott and W. S. Peart, ibid., 1957, 65, 246.52 L. T. Skeggs, K. E. Lentz, J. R. Kahn, N. P. Shumway, and K. R. Woods,53 R. Schwyzer and P. Sieber, Chimia, 1956, 10, 265.54 W. Rittel, B. Iselin, H. Kappeler, B. Riniker, and R. Schwyzer, Angew. Chem.,Nature, 1955, 176, 687.J . Exp. Med., 1956, 104, 193.1957, 69, 179; Helv. Chim. Acta, 1957, 40, 614284 ORGANIC CHEMISTRY.I 2 3 4 5 6 7 8 9 1 0(15) Asp.arg.val.tyr.va/.his,pro.phe.HIS.LEu.Va16-Hypertensin-/ (ox): removal of residues 9 ond I0 yields Va15-Hypertensin-I/ (ox).I 2 3 4 5 6 7 8 9 1 0( I 6) Asp.arg.val.tyr.ileu.his.pro,phe.HIs.LEu./leu6-Hypertensin-l (horse); removal of residues 9 and I0 yields ileu6-Hypertensin-l/ (horse).R CHMea CHMe, CHMeBCHC0.N H*CH*CO*O*CH*CO*N H*CH*COI I I III0II 0~~OSCH-N H-COCH ~OCOCH~N H-COCH I I I ICHMe, CHMe, CHMel R( I 7) Vdinomycin: R = Me(18) Amidomycin: R = Pr*(For t h e stereochemistry, see text)CHMe, Me CHMe, 1 I 1ICHC0.N-CHCO0 0 IDABy-NHg + D-phe thrJ.DAB-7-N H 2 + y-N H e-DAB2 DAB +++thrD-DAB-y-NHlpelCHMe2 CHMea(19) Enniatin €5++++DA B-y-N H 2thrD-DAB-Y-NH,lpel(20) (21)DAB = my-diaminobutyric acid.lpei = isopelargonic acid.Amino-acid residues have the L-configuration unless otherwise stated. The carboxyl-group ofthe residue at the t a i l of the arrow is joined t o the amino-group of the residue a t i t s headYOUNG : AMINO-ACIDS, PEPTIDES, AND PROTEINS. 285It has been known for some time that peptides (strepogenins) present inpartial hydrolysates of certain proteins will stimulate the growth of micro-organisms such as Lactobacillus ~ a s e i .~ ~ Merrifield and Woolley have now iso-lated two pep tides, ser. his. leu .Val&. and ser. his.leu.va1. glu. ala.leu, withstrepogenin activity, from the partial hydrolysis of beef insulin by acid. 56The former has been ~ynthesised.~~Apart from glutathione, few small peptides have been isolated fromliving cells, but recent investigations suggest this scarcity is more apparentthan real. Turba and Esser 58 obtained evidence of the presence of some40 peptides in extracts of yeast cells, and Waley has now separated a numberof peptides from the lens of the calf, and has identified two components,y-L-glutamyl-L-a-aminobutyrylglycine (ophthalmic acid) and y-glutamyl-alanylglycine (norophthalmic acid), the former having been synthe~ised.~~The steric resemblance to glutathione is noteworthy.The investigation of peptides isolated from bacteria has continued toreveal structures significantly different in type from those from othersources.Recent work on the actinomycins is discussed elsewhere; Go butmention must be made here of the isolation from Stveptomyces species of twoantibiotic substances of quite a different structure, valinomycin 61 (probably17) and amidomycin 62 (18). The former contains two units of D-a-hydroxy-isovaleryl-D-valine, linked in a ring system by two units of L-lactyl-L-valine.The latter contains four units of D-a-hydroxyisovaleryl-D-vafine, in a ringof the same size. There is a clear resemblance.to the structure of theenniatins (19) , found in species of Fusa~izmz.~~Polymyxin-BI (separated by count er-current distribution from themixture of peptides secreted by Bacillzls fioljwzyxa) is considered to havestructure (20) or (21).64 During the continued investigation of bacitracin A,the remarkable resistance of e(wasparty1)lysine (and its p-isomer) to acidhydrolysis has been demonstrated,G5 prolonged attack giving the aspartimide(22). Another unusual type of structure occurs in phallaidin (23), a toxic5 6 H. Sprince and D. W. Woolley, J . Amer. C h e w SOC., 2945, 67, 1734.5 7 Idem, ibid., p. 4646.68 F. Turba and H. Esser, Biochem. Z., 1955, 327, 93.60 S. G. Waley, Biochem.J., 1956,64,715; 1957, 67, 172; 1958, 88, 189.6o This vol., p. 347.61 H. Brocltmann and H. Geeren, Annalen, 1957, 603, 216.62 L. C. Vining and W. A. Taber, Canad. J . Chem., 1957, 95, 1109.63 P. A. Plattner and U. Nager, Helv. Chim. Acta, 1948, 31, 2192.64 W. Hausmann, J . Amer. Chem. SOL, 1956, 78, 3663; G. Biserte and M.Dautrevaux, Bull. SOC. Chim. b i d , 1957, 39, 795.6 5 I. M. Lockhart and E. P. Abraham, Biochem. J., 1956, 62, 645: D. L. Swallowand E. P. Abraham, ibid., 1957, 65, 39P; D. Theodoropoulas and L. C. Craig, J . Org.Chem., 1956, 21, 1376. For,: review of the biochemistry of bacitracins and cephalo-sporins, see E. P. Abraham, Biochemistry o i Soxe Peptide and Steroid Antibiotics,”Wiley, New York, 1957.R. B. Merrifield and D.W. Woolley, ibid., 1956, 78, 358286 OKGANIC CHEMISTRY.cyclic peptide isolated from toadstools (Amanda phalloides) ; a full accountof the degradation evidence has appeared.66MeC = CH-CHeNH - CO.CH * NH.CO.CH - CH,I(23) PholloidinMe-CH. OHFor progress made in the establishment of amino-acid sequences in suchimportant proteins as the haemoglobins, serum albumens, tobacco mosaicvirus, silk frbroin, collagen, and wool keratin, reference should be made toAnfinsen and Redfield's stimulating review,67 and to a painstaking analysisof the amino-acid arrangements so far encountered in natural peptides andproteins given by $ o m and his co-workers.68It was mentioned above that by the action of leucine aminopeptidase onmercuripapain some 120 of the 180 amino-acid residues may be removedwhilst enzymic activity is still retained in the regenerated residue.This isthe most remarkable example of an increasing number of observations(summarised by Anfinsen and Redfield 67), in which biologically activepeptides and proteins have been degraded without loss of activity, and thereis the exciting prospect not only of a great simplification of structuralinvestigations in this way but also of discovering the essential requirementsfor activity. A parallel approach is the elucidation of the sequence ofamino-acids at the " active site " of an en~yme,~g and by degradation ofthe 32P-phosphorylated enzyme Koshland and Erwin 70 have found that theamino-acids at the active centre of phosphoglucomutase are the same asthose at the active centre of chymotrypsin, for which the sequenceasp.ser.gly.glu.ala has been proposed.71 This is consistent with a suggestionthat some bond-breaking mechanisms may be common to enzymes of widelydifferent specificities.The report of the Faraday Society Discussion on" The Physical Chemistry of Enzymes," which contains important contri-butions concerning the mechanism of enzymic action, appeared in the periodunder review.72 The report 73 of a recent symposium on the structure andfunction of proteins gives authoritative discussions of the present state ofour knowledge of the chemical basis of biological activity of the growthhormone (somatotropin) , ribonuclease, trypsinogen and chymotrypsinogen,66 T. Wieland and W.Schon, Annulen, 1955, 593, 157.67 C. B. Anfinsen and R. R. Redfield, A d v . Protein Chem., 1956, 11, 1.68 F. Sorm, B. Keil, V. HoleySovsky, V. KnezslovA, V. Kostka, P. Masiar, B. Meloun,0. Mikes, V. TomBSek, and J . VanECek, Coll. Czech. Chem. Comm., 1957, 22, 1310.68 See, e.g., W. N. Aldridge, Ann. Reports, 1956, 53, 301.70 D. E. Koshland and M. J . Erwin, J. Amer. Chem. Soc., 1957, 79, 2657.72 Discuss. Furuduy SOC., 1955, 20.73 Fed. Proc., 1957, 16, 774.F. Turba and G. Gundlach, Biochem. Z . , 1955, 327, 186YOUNG AMlNO-A4CIDS, PEPTIDE;S, AND PROTEINS. 257papain, and tobacco mosaic virus, and it is clear that we are on the thresholdof significant developments in this field.Synthesis of Peptides-The last two years have seen outstanding achieve-ments in this field also, largely by the methods developed previou~ly.~*Benzyloxycarbonyl remains the most generally useful amino-protectinggroup, but toluene-9-sulphonyl (tosyl) and triphenylmethyl (trityl) haveproved valuable in recent syntheses; the last has the advantage that it maybe removed under mild acid conditions; its steric effect affords alternativeroutes to a- and y-glutamyl-peptides, since partial saponification of thediester gives a-ethyl N-trityl-L-glutamate, and partial methanolysis ofdibenzyl N-trityl-L-glutamate yields the a-benzyl y-methyl ester.75 Morerecently it has been reported 76 that the N,-trityl group of N,N,-ditrityl-lysyl-peptides can be removed preferentially by acid, so providing a newsynthesis of peptides coupled through the a-amino-group of lysine.Amongnew suggestions, tert.-butoxycarbonyl and cyclopentyloxycarbonyl are likelyto be particularly useful amino-protecting groups since they are resistant tohydrogenation and to sodium in liquid ammonia but are removed byhydrogen bromide or hydrogen chloride in acetic acid or nitromethane."Some years ago, Ehrensvard 78 proposed the phenylthiocarbonyl groupfor amino-protection, but cleavage by lead tetra-acetate does not proceedsmoothly. 79 The discovery that aryl- and alkyl-thiocarbonyl groups canbe removed satisfactorily by perbenzoic acid 8o suggests that they will nowfind application in synthesis.The carbodi-imide method of coupling 8 l is proving very valuable; tofacilitate the separation from the urea co-product, carbodi-imides givingwater- or acid-soluble urea have been recommended : 82RC0,H + C,Hll*N=C=N~C,H,,*NEt, + R'*NH1 + RCO-NHR' + C6HIl*NH*CO*NHoC,,Hlo*NEt,An interesting application of the carbodi-imide method is in forming the4-membered cyclic amide during a total synthesis of penicillin-Vm and it hasbeen used to cyclise glycyl-DL-valylglycylglycyl-DL-valylglycine, in solutionin SO% methanol.@ A water-soluble carbodi-imide has been used to cross-link gelatin (by amide formation) in aqueous solution, yielding a gel in 30seconds.85T4 Reviews: H. D. Springall and H. D. Law, Quart. Rev., 1956, 10, 230; W. Grass-mann and E. Wunsch, Fortschr. Chem. org. Naturstofle, 1956, 13, 444; T. Wieland andB. Heinke, Angew.Chem., 1957, 69, 362; G. W. Kenner, J., 1956, 3689; M. Goodmanand G. W. Kenner, Adv. Protein Chem., 1957, 12, 465.75 G. Amiard, R. HeymAs, and L. Velluz, Bull. SOC. chim. France, 1956, 97.'13 G. Amiard and B. Goffinet, ibid., 1957, 1133.77 F. C. McKay and N. F. Albertson, J . Amer. Cheni. Soc., 1957, 79, 4686; G. W.79 A. Lindenmann, N. H. Khan, and K. Hofmann, J. Amer. Chem. SOC., 1952,74,476.82 J. C. Sheehan and J. J. Hlavka, J. Org. Chem., 1956, 21, 439.83 J. C. Sheehan and K. R. Henery-Logan, J. Amer. Chem. Soc., 1957, 79, 1262.8 5 J. C. Sheehan and J. J . Hlavka, J. ,4nzer. Chem. Soc., 1957, 79, 4528.Anderson and A. C. McGregor, ibid., p. 6180.G. C. H. Ehrensviird, Nature, 1947, 159, 500.J. Kollonitsch, A. Hajbs, and V. GAbor, Ghem. Bey., 1956, 89, 2288, 2293.J . C.Sheehan and G. P. Hess, J. Amer. Chem. SOL, 1955, 77, 1067.T. Wieland and K. W. Ohly, Annalen, 1957, 605, 179288 ORGANIC CHEMISTRY.The use of activated esters has been considerably developed. Afterexamination of a number of such esters, Schwyzer 86 recommended cyano-methyl esters; they are formed readily from the acylamino-acid by the actionof chloroacetonitrile in the presence of triethylamine, and react smoothlywith amino-esters giving high overall yields. In the same laboratory aninteresting attempt was made to use tetrahydropyranyl esters, prepared bythe addition of the carboxylic acid to 2 : 3-dihydropyra11,~~ but the amino-component combines with the 6-hydroxypentanal formed and so limits theyield of peptide from the amine:The same paper describes the protection of hydroxyl groups by means of theShydropyran, but a disadvantage is the presence of an additional asym-metric centre in the adduct. The usefulness of p-nitrophenyl and thiolesters has been limited by the methods available for their preparation,88but two interesting new methods for the preparation of aryl esters have beenreported,89 using diary1 sulphites or triaryl phosphites, in the presence ofpyridine :(0) R.CO2H(b) 2R.COZH + (P-NO2'CIH4*O)BP __t 2R.COaoC6Hp*NO2 + NOa*C6H4.OaPO2H2(p-NOsC6Hp'O)aSO + R.COI.C6H4*NOs + NO,*C,H4*OH + SO*In both cases the yields are nearly quantitative. This esterification has alsobeen effected by means of dicyclohexylcarbodi-imide; by using a largeexcess of p-nitrophenol, acylurea formation should be reduced.The use ofpropargyl esters, prepared by the action of propargyl bromide on the triethyl-amine salt of the acid, has been suggested in a preliminary communi~ation.~~Activated esters are proving valuable for the cyclisation of peptides, sincetheir stability permits the removal of amino-protecting groups such asbenzyloxycarbonyl and triphenylmethyl, as, for example, in the synthesis ofgramicidin-S 92 (24).The reactivity of acetylenic ethers (cf. the use of dihydropyran, above)is the basis of a method of coupling devised by Arens: 93R.CO,H + Et0.C-CH + R'-NH2 __t R.CO*NHR' + CH,*CO,EtSheehan has used both this method and a novel one involving the addition86 R. Schwyzer, B. Iselin, and M.Feurer, Helv. Chim. Acta, 1955, 38, 69;R, Schwyzer, M. Feurer, B. Iselin, and H. Kaigi, ibid., p. 80; R. Schwyzer, M. Feurer,and B. Iselin, ibid., p. 83.87 B. Iselin and R. Schwyzer, Helv. Chim. Acta, 1956, 39, 57.M. BodBnszky, Acta Chim. Acad. Sci. Hung., 1957, 10, 335; M. BodBnszky,M. Szelke, E. Tomorkhy, and E. Weisz, ibid., 1957, 11, 179; J. A. Farrington, P. J.Hextall, G. W. Kenner, and J. M. Turner, J., 1957, 1407.sg B. Iselin, W. Rittel, P. Sieber, and R. Schwyzer, Helv. Chim. Acfa, 1957, 40, 373.D. F. Elliott and D. W. Russell, Biochem. J., 1957, 66, 49P.B1 M. Bodhszky, Chem. and Ind., 1967, 524.92 R. Schwyzer and P. Sieber, Helv. Chim. Acta, 1957, 40, 624.g3 J. F. Arens, Rec. Trav. chim., 1955, '74, 769; ref. 2 ( b ) , p. 468YOUNG : AMINO-ACIDS, PEPTIDES, AND PROTEINS.289of the acid to the keten imine, cyclohexyliminomethylenecyclohexane, forthe cyclisation of D-a-phenoxymethylpenkilloic acid to penicillin V, but theyields were lower than that obtained with dicyclohexylcarbodi-imide. 83The preservation of optical activity is always an important considerationin peptide synthesis, and it is known than methods of coupling which givefully active products from benzyloxycarbonylamino-acids may lead toracemisation when benzyloxycarbonyl-peptides are further coupled. 94 Anexamination has been made of the optical activity of the products obtainedwhen various methods are used to couple acetyl-L-leucine with glycine ethylester.95 Methods involving mixed anhydrides led to considerable racemis-ation in this reaction, but the use of acid azides, cyanomethyl esters, ordicyclohexylcarbodi-imide gave active material ; an unexpected finding isthat racemisation of the acylating residue may result even when methods ofcoupling are used (such as the “ phosphorazo ” and the phosphoramideprocedure) which have been postulated to involve activation of the amino-component.In manycases, extensive use was made of counter-current distribution for the puri-fication of both intermediates and final product.One of the outstandingsyntheses during the period under review is that of an eicosapeptide methylester having the sequence of the first 20 N-terminal residues common toCC- and @-corticotropin, (11) and (12).g6 The product had positive, thoughlimited ’’ hormonal activity, although it is four residues shorter than thesmallest biologically active fragment so far obtained by degradation of thehormone.The antibiotic cyclic decapeptide gramicidin-S (24) has beensynthesised by Schwyzer’s group 92 and an outline of the final stages is givenin the accompanying chart. Preliminary announcements have been madeof the synthesis of the decapeptide va15-hypertensin-I ” (15),97 and of theaspartyl-p-amides of “ va15 ”- and “ ileu5-hypertensin-I1 ” (see above),98 anda full account of the last synthesis has appeared.99 Although the structuralevidence indicates an N-terminal aspartic acid residue in the hypertensins,these asparaginyl analogues have physiological activity comparable with thatof the natural products.An improved synthesis of lysine-vasopressin (25)has been reported,loO and two new syntheses of oxytocin (26),lo1 togetherwith syntheses of analogues in which the isoleucyl residue of oxytocin hasbeen replaced by phenylalanine, valhe, or leucine, and of one in which theasparagine residue has been replaced by glutamine; in each case so farSome of the important syntheses achieved will now be noted.94 Cf., e.g., J. R. Vaughan, J . Amer. Chem. SOC., 1952, 74, 6137.95 M. B. North and G. T. Young, Chern. and Ind., 1955, 159; M. B. North, N. A.Smart, and G. T. Young, Abs. Roc. 19th Internat. Congr. Pure Appl. Chem., Paris,1957, 11, p. 238.96 R. A. Boissonnas, St. Guttmann, J.-P. Waller, and P.-A. Jaquenoud, Experientia,1956, 12, 446.9’ R.Schwyzer and P. Sieber, Chimia, 1956, 10, 265.98 W. Rittel, B. Iselin, H. Kappeler, B. Riniker, and R. Schwyzer, Angew. Chem.,g9 Idem, Helv. Chim. A d a , 1957, 40. 614.loo V. du Vigneaud, M. F. Bartlett, and A. Johl, J . Amer. Chem. Soc., 1957, 79, 5572.l01 J. Rudinger, J. Honzl, and M. Zaoral, Coll. Czech. Chem. Cowam., 1956, 21, 202;L. Velluz, G. Amiard, J. Bartos, B. Goffinet, and R. HeymBs, Bull. SOC. chim. Fvance,1956, 1464.REP.-VOL. LIV K1957, 69, 179290 ORGANIC CHEMISTRY.CBzo.val.orn.leu.D.phe.pro.0MeITosT-va1.orn.leu.D-phe.pro I Tosval.orn.1eu.D-phe.pro.OMeITosT-val.orn.leu.D-phe.pro.;al.orn.leu.D-phe.pro.OMe I Tos I TosT-val.orn.leu.D-phe.pro.val.orn.leu.D-phe.pro.0NP I Tos I TosTos Tosval.orn.1eu.D-phe.pr0.val.orn.leu.D-phe.pro 1The later stages of the synthesis of gramicidin-S.Reagents: (a) Pd-Ha.(b) Ph3CCI. (c) NaOH. (d) I-cycloHexyl-3-(2-rnorpholinoethyl)-carbodi-imide. (e) Di-p-nitrophenyl sulphite in pyridine. ( f ) CFs*C02H. (g) Pyridine. (h) Na-NHS.CBZo = Ph*CH,*OCO-; TOS = p-C,H4Me*S02 = toluene-p-sulphonyl; T = Ph3C-; ONP =Amino-acids have the L-configuration unless otherwise shown.p-NO,.C,Hp'O.(26) OxytocinS S I IH2N NH,Arginine-vasopressin Phe(25) Lysine-vasopressin PheI' Oxypressin " (synthetic) PhYOUNG : AMINO-ACIDS, PEPTIDES, AND PROTEINS. 291reported, the products have modified biological activity.lo2 The analogueof oxytocin in which the asparagine residue is replaced by isoglutamine hasnow been synthesised,lo3 and it is interesting that the oxidation of thedithiol to the 22-atom cyclic disulphide proceeded even more smoothly thanin the case of the 20-atom ring of oxytocin.The product was biologicallyinactive. In this work a reminder has appeared that reagents which activatea carboxyl group may also attack less reactive parts of the molecule; whena peptide containing an asparagine residue was coupled by the tetraethylpyrophosphite method a by-product was formed which, in the simplestinterpretation, could have been the side-chain nitrile, since hydrolysis yieldedaspartic acid, while sodium in liquid ammonia gave a peptide which onhydrolysis gave ay-diaminobutyric acid.lM Other workers have obtainedconsiderable amounts of an anhydro by-product when coupling benzyloxy-carbonyl-L-asparagine with S-benzylcysteine methyl ester, using eithertetraethyl pyrophosphite or dicyclohexylcarbodi-imide ; this by-product wasabsent when coupling was effected through a mixed carbonic or carboxylicanhydride.lo5 The analogous reaction with benzyloxycarbonyl-L-glutaminegave a small amount of anhydro-material when the tetraethyl pyrophosphitemethod was used.The coupling of acylasparagines generally gives lowyields, probably owing to formation of the acylaspartimide ; the formationof the imide from c-aspartyl-lysines has been mentioned above. It isinteresting that dehydration of the asparaginyl or glutaminyl side chain,followed by hydrogenation, has been used for the synthesis of peptides ofay-diaminobutyric acid and of ornithine respectively; lo6 since the side chainof ornithine reacts with O-methylisourea to give the corresponding argininederivative, this sequence may provide a useful route to peptides of arginine.Three new syntheses of glutathione have been described; lo7 in the first,the triphenylmethyl group was used to protect both the amino- and thethiol group of the cysteine; and in the second these were protected byreaction with acetone to yield the 2 : 2-dimethylthiazolidine-4-carboxylicacid. The culmination of a long series of researches on the structure of theimmuno-specific capsular polypeptide formed by the anthrax bacillus hasbeen reached with the synthesis of a y-poly-D-glutamic acid, similar inC0,Me COsMe I I N H 2.C H [C H 21 ,*CO* N H*C H [C H ,CO*S P h (27)physical and immunological properties to the natural polymer.los This wasachieved by the polymerisation of the dimethylphenyl y-D-glutamyl-D-thiol-glutamate (27).It is interesting that the isomer in which y-L- and Y-D-102 P. G. Katsoyannis, J . Amer. Chem. SOC., 1957, 79, 109; R. A. Boissonnas, St.Guttmann, P.-A. Jaquenoud, and J.-P. Waller, Helv. Chim. Acta, 1956, 39, 1421 ;J. Rudinger, J. Honzl, and M. Zaoral, Coll. Czech. Chem. Comm., 1956, 21, 770.lo3 C . Ressler and V. du Vigneaud, J . Amer. Chem. SOC., 1957, 79, 4511.lo* C. Ressler, ibid., 1956, 78, 6956.lo5 D. T. Gish, P. G. Katsoyannis, G. P. Hess, and R. J. Stedman, ibid., p. 6954.lo6 M. Zaoral and J. Rudinger, Proc. Chem. Soc., 1957, 176.107 G.Amiard, R. Heymhs, and L. Velluz, Bull. SOC. chim. France, 1956, 698;F. E. King, J. W. Clark-Lewis, and R. Wade, J., 1957, 880; F. Weygand and R. Geiger,Chem. Ber., 1957, 90, 634.108 V. Bruckner, J. Wein, M. KajtAr, and J. KOVBCS, Naturwiss., 1955, 42, 463292 OKGANIC CHEMISTRY.glutamyl residues alternate also gave a precipitate with anti-anthrax~erurn.l0~, A valuable summary has appeared of the physicochemicalinvestigations of polypeptides of high molecular weight prepared bypolymerisat ion .ll1A full reportu2 has now been presented of the remarkable reaction bywhich amino-acid residues may be interpolated into a peptide chain throughthe intermediate formation of the O-aminoacylsalicyloyl-peptide (28) ;analogously, debenzylation of 0-(cebenzyloxycarbonylaminoacy1)salicylicacids yields salicylamido-acids quantitati~ely.~~ This reaction, termed‘ I Aminoacyjl Einlagerung, ’’ has been used to synthesise salicyloylglycyl-phenylalanylglycine, and has been extended to the use of O-aminoacylderivatives of aliphatic p-hydroxy-acids, although stronger bases are requiredto effect the rearrangement in these cases.The interesting suggestion ismade that serine, threonine, or cysteine residues may be used in this fashionin the biological synthesis of proteins, so lengthening the chain from thecentre rather than from the end.G. T. Y.12. CARBOHYDRATES.Stereochemical and Mechanistic Aspects-At present there is considerableinterest in both the stereochemistry of carbohydrates and the mechanismsof their reactions, and symposia on these subjects have been held recently.l,In an important publication further consideration has been given to theshapes of the pyranose ring and attention has been directed to the importanceof boat forms.In sodium hydroxide some glycosides show relatively largereversible changes in optical r ~ t a t i o n , ~ The hypothesis is put forward thataxial hydroxyl groups in neutral solutions tend to move to equatorialpositions at high alkalinity (when the ionised solvated sugar hydroxyl groupshave a greater effective volume) and this produces a rotational change.There is good correlation between experiment and theoretical predictions.As the changes would lad, in certain cases, to boat forms, the furthersuggestion is made that although chair forms are generally of lower energythan boat forms the difference is more than offset when a boat form allowsall ring substituents (other than hydrogen) to be equatorial.3 Geometricallyloo V.Bruckner, J. Wein, M. KajtAr, and J. KovAcs, Natztrwiss., 1957, 44, 89.110 Review: V. Brucknerand J. Kodcs, ActaChirn. A c e . Sci. HuHg., 1957,12,36!;111 C . H. Bamford, A. Elliott, and W. E. Hanby, Synthetic Polypeptides,Academic Press, New York, 1956.112 M. Brenner, J. P. Zimmemann, J. Wehrmiiller, P. Quitt, A. Hartman, v\i.Schneider, and U. Beglinger, Helv. Chim. Acta, 1957, 40, 1497; M. Brenner and J.Wehrmiiller, ibid., p. 2374.113 M. Brenner and J. P. Zimmermann, ibid., p. 1933.1 See G. R. Barker, Proc. Chem.Soc., 1957, 10.3 R. E. Reeves and F. A. Blouin, J . Amer. Chem. Soc., 1957, 79, 2261.4 R. E. Reeves, ibid., 1950, 72, 1499.Abs. Amer. Ckm. SOC. 132nd Meeting, 1957, KDOVEREND : CARBOHYDRATES. 293regular boat forms are unlikely in some simple pyranosides because of thehigh energy resulting from eclipsed valency angles on some of the adjacentatoms. Consequently the suggestion should be construed to mean that thering may take a shape approximating to that of a pure boat form, butdistorted in the region where the tendency of the large groups to move intothe equatorial plane is balanced by the repulsion brought3 ~ * * 2 ~ about by approach to the eclipsed-valency position. Boat-form rings are flexible, so that positions intermediate be- - #B3 tween Reeves’s designated forms can occur without greatlyincreased ring strain. There is a sequence in which oneboat form may be changed into another, e g ., (l), and,provided certain of the forms are not prohibited by steric interference ofsubstituents, boat forms may shift in either direction through the cycle ofchanges (1). As a result of this work further consideration of the designation ofring shapes is required, as Reeves’s descriptions are not sufficiently precise.Configurational and conformational effects in the proton magneticresonance spectrum of acetylated carbohydrates have been observed.5 Thespectra confirm the anomeric configurations of sugar acetates assigned onthe basis of Hudson’s rule of isorotation. There is evidence that hydrogenbonding of the 4-hydroxyl group to the ring-oxygen atom effectively fixesthe conformation of ~-erythro-3 : 4-dihydroxypyran (1 : 2-dideoxy-~-arabo-pyranose) in both carbon tetrachloride and aqueous solution.6 The re-fractive indices and densities of hexo- and pento-pyranosides (with theexception of methyl a-L-arabinoside) similarly substituted on correspondingring atoms increase with increasing number of axial substituents.’ Methyl4 : 6-O-ethylidene-cc-~-mannoside (2) and 1 : 6-anhydro-P-~-mannopyranose(3) (or its 4-methyl ether) undergo selective esterification at the equatorialhydroxyl group.8 The reaction of glyco-furanosides and -pyranosides withborate ions has been mea~ured.~ In certain pyran derivatives the reactionof vicinal cis-hydroxyl groups with borate ions is hindered by a vicinal cis-methoxy-group.10 Terdentate complex formation l1 is not responsible forthe effect and it is considered that conformations other than the preferredchair forms are involved.For example, methyl p-D-lyxopyranoside (4;R” = OMe, R’ = H) interacts with borate ions less than does the a-anomer(4; R‘ = OMe, R” = H).9 If the half-chair conformation (5) is involvedin the interaction, it is clear that in it the p-form leads to greater interactionbetween R” and the 2-hydroxyl group, and so the change (4) (5) willoccur less readily than for the a-isomer.3-0-Substituted aldoses and 4-0-substituted hexuloses take up hydrogenonly slowly from borohydride in borate buffer l2 because of steric hindrance.R.U. Lemieux, R. K. Kullnig, H. J. Bernstein, and W. Schneider, ibid., 1967,J. S. Brimacombe, A. B. Foster, and D. H. Whiffen, Abs. Amer. Chem. SOC.,R. B. Kelley, Canad. J. Chem., 1957, 35, 149. * G. 0. Aspinall and G. Zweifel, J., 1957, 2271.A. B. Foster, J., 1957, 1395.ti f C B?( 1 )79, 1005.132nd Meeting, 1957, 2D.lo Idem, ibid., p. 4214.l1 S. J. Angyal and D. J. McHugh, Chem. and Ind., 1956, 1147.l* P. D. Bragg and L. Hough, J., 1957,4347294 ORGANIC CHEMISTRY.Reduction to the hexitol(8) will be preceded by ring opening, e.g., (6) 4 (7)for a 3-O-substituted glucose, and in the acyclic staggered zig-zag conform-ation (7) a bulky 3-substituent hinders approach to the aldehyde group.H HH" O m R , ,Ho H( 4 ) ( 5 )There is correlation between the size of the group R and the rate of reduction.Smaller differences in reduction rates of other monosaccharides are attribut-able to borate-complex formation involving the cyclic form of the sugar.Steric hindrance of the carbonyl group in ketoses results in slower reductionthan with aldoses.The polarographic reduction of pentoses, hexoses, theirmethyl ethers, and 2-deoxy-analogues has been examined.13 Limitingcurrents are determined by the rates of transformation of the ap-equilibriummixtures of the sugars from ring to reducible form at the mercury surface.For some of the methylated derivatives the rate of transformation toreducible form is sufficiently high to render diffusion the rate-controlling( 6 ) Hstage.A correlation has been noted between bulk rate constantstransformations and the conformational instability units 4 of thesugars.for thevariousTreatment of a large excess of galactitol or mannitol with periodateafforded a tetrose or, mainly, glyceraldehyde respectively, indicatingpreferential oxidation of threo-glycol groups.14 The rates of periodateoxidation of methyl 4 : 6-O-benzylidene- and 4 : 6-O-ethylidene-a-~-aldo-hexosides can be correlated with the disposition of the hydroxyl groups inthe preferred conformations of the compounds.15 Periodate forms reversiblya complex with a cis-cis-1 : 2 : 3-trio1 system of a six-membered ring: 16 this13 W. G. Overend, A. R. Peacocke, and J. B. Smith, Chew. and Ind., 1957,113, 1383.14 J. C. P. Schwarz, J., 1957, 276.1 5 J.Honeyman, K. S. Ennor, C. J. G. Shaw, and T. C. Stening, Abs. Amer. Chem.16 G. R. Barker and D. F. Shaw, Proc. Chern. Soc., 1957, 259.Soc., 132nd Meeting, 2957, 4DOVEREND : CARBOHYDRATES. 295retards the rate of oxidation. Steric considerations suggest that the triolsreact in the conformation in which one hydroxyl group is equatorial and twoare axial, e.g., (9). The complex is thought to be more....- stable than that formed between periodate and di0ls.l' Itis unstable in acid. Decomposition of the ribose complexto give iodate and oxidation products follows first-orderkinetics up to 75% destruction of the pentose. Duringoxidation of glucose by alkaline iodine solution it isimportant to keep the concentration of potassium iodide as low as possible,consistent with the necessity of maintaining a sufficient excess of iodine untiloxidation is complete.18 The kinetics of oxidation of glucose, galactose,fructose, arabinose, and xylose by alkaline bivalent copper in the presenceof citrate and tartrate have also been investigated.lsThere is continuing interest in aspects of the halogen oxidation of sugars.Application of bromine oxidation to the study of ring conformation has been21 Bentley 21 concludes that the following generalization- can bedrawn : " for any pyranose of stable CI conformation regardless of member-ship in the D- or L-series, the more dextrorotatory member of the anomericpair will have the anomeric substituent in the axial position.Similarly, forany pyranose of stable IC conformation, regardless of membership in theD- or L-series, the more laevorotatory member of the anomeric pair will havethe anomeric substituent in the axial position.The anomer with theglycosidic substituent in the axial position will in general be the leastreactive. "The conclusion 22 that in the oxidation of glucose the rate-determiningattack by bromine occurs at the 1-hydroxyl group has been disproved bymeasurements of hydrogen-isotope effects.23 Oxidations of l-tritio-cc- and-p-D-glucose demonstrated that the rate-determining step involves ruptureof the C(,I--H bond. Bentley21 now suggests that an initial rapid andreversible formation of pyranose-halogen complex is followed by a rate-determining transfer of a hydride ion, as illustrated, the step RD beingrat e-det ermining.IO.;:......OH( 9 )HO *-. 270 - H 5 B r 2 H - +i0 0 - H + 0'2 zsz a B,Q* + "+The greater reactivity of the anomer in which the hydrogen at position Iis axial is considered to be due to the fact that the rate-determining step isfavoured by the release of strain. This is the reverse of the usual situationl7 G. J. Buist and C. A. Bunton, J., 1954, 1406.18 R. L. Colbran and T. P. Nevell, J., 1957, 2427.2o H. S. Isbell, Abs. Amer. Chem. SOC., 132nd Meeting, 1957, lo.21 R. Bentley, J . Amer. Chem. SOL, 1957, 79, 1720.Z2 Idem, Nature, 1955, 176, 870.23 F. Friedberg and L. Kaplan, Abs. Amer. Chem. SOC., 131st Meeting, 1957, 860.M. P. Singh and P. Ghosh, 2. phys. Chem.(Leipzig), 1957, 207, 187, 198296 ORGANIC CHEMISTRY.in cyclohexane compounds and is attributable possibly to the repulsive forcesassociated with the unshared electrons of the ring-oxygen atom.= Oxidationof methyl p-D-glucopyranoside with an aqueous chlorine system at pH 4.5yields, as maj or products, D-ghCOSe, D-arabinose, carbon dioxide, and oxalicacid; minor products include 2-0x0- and 2 : 5-dioxo-gluconic acid.25 Theglycoside is not hydrolysed under the conditions employed and it wasconcluded that either there is attack on the glycosidic bond in a combinedoxidation and hydrolysis or the oxidant attacks the methyl group yielding anew and more sensitive aglycone. D-Arabinose arises via its carbonate esterby cleavage of the 1 : 2-bond of the glycoside.The carbon dioxide andoxalic acid could not be attributed to any single definite source. 2 : 5-Dioxo-gluconic acid probably arises from oxidation of glucose via the 2-0x0-derivative.The action of phosphorus pentachloride on octa-0-acetylcellobiose and astudy of the anomeric acetates of sugars are reported.26 The known re-action 27 between sugar acetates and anhydrous aluminium chloride has beendeveloped into a general method for preparing 1 : 2-tram-acetylglycosylhalides, both pyranose and furanose, from 1 : 2-trans-acetates of p-D-aldoses.28The 1 : 2-cis-epimers of the sugars do not react under the conditions employed.Measurement of the rate of reaction with silver acetate in benzene offers aconvenient means for distinguishing between 1 : 2-cis-chlorides, 1 : 2-trans-chlorides, and orthoacetyl chlorides.28 In 2 : 3-di-0-acetyl-4 : 6-O-benzyl-idene-P-D-glucopyranosyl chloride (10; R = Ph) or the 4 : 6-O-ethylidenederivative (10; R = Me), which show behaviour typical of their class, thering junction prevents the conversion of the CI chair conformation of thepyranose ring into the IC chair conformation required for replacements atposition 1 according to Lemieux’s mechanism,29 but anchimeric assistance bythe %acetate group is still very apparent in reactions atposition 1.The antiparallel orientation of the chlorine atomCI and the acetate group 28 may be obtained without excessivesteric strains by conversion of the pyranose ring form of (10)into the appropriate boat form.The kinetics of the un-catalysed and catalysed solvolyses of 1 : 2-trans-2-0-acetylglycosyl halidesshow that the rate-determining stage is the removal of the halogen atom toform a cyclic carbonium i0n.30 Anchimeric assistance due to the 2-acetylgroup contributes to the enhanced solvolysis rates of 1 : 2-trans-2-0-acetyl-glycosyl 1 -halides compared with the corresponding 1 : 2-cis-compounds.Comparison of the solvolysis of tetra-0-acetyl-p-D-glucosyl chloride and tetra-O-acetyl-a-D-mannosyl chloride (both trans-compounds) illustrates the im-portance of other factors which govern reactivity. It has been suggestedthat these steric factors may be attributed either to hindrance by the large.‘:Tt,. H 3 2.(lo) AcO OAc84 Cf. J. T. Edward, Chem.and Ind., 1955, 1102.25 J. T. Henderson, J. Amer. Chem. SOL, 1957, 79, 5304.26 S. N. Danilova, 0. P. Koz’mina, and A. N. Shirshova, Zhur. obshchei Khim.,27 G. Zemplkn, L. Mester, and E. Eckhart, ActaChim. Acad. Sci. Hung., 1954,4, 73.s8 W. Korytnyk and J. A. Mills, Chem. and Ind., 1957, 817.29 R. U. Lemieux and C. Brice, Canad. J .Chew., 1956, 34, 1006; R. U. Lemieux8 0 G. L. Mattok and G. 0. Phillips, J., 1967, 268.1957, 27, 945.and J. D. T. Cipera, ibid., p. 906OVEREND : CARBOHYDRATES. 297groups to the realisation of a planar configuration of the ion, or to sterichindrance to the solvation of the ion.Conformational and mechanistic aspects of glycoside hydrolysis have beendiscussed in terms of a cyclic 1 and an acyclic 3 l carbonium ion intermediate.The influence of a keto-group on the stability of the glucosidic linkage hasbeen examined.32More measurements have been made33 of the rate of mutarotation ofD-glucose in unbuffered alkaline solutions.The reason for the establishedgreater acidity of p-D-glucose than of the a-form lies in the considerabledifference in entropy change upon ionization of the two isomers. Neutralsalts modify both the speed of mutarotation and the equilibrium rotation ofglucose, fructose, galactose, and maltose.34 The uncatalysed and acid-catalysed mutarotations of tetra-0-methyl-a-D-glucose in solvents D20 andH20 have been e~amined.~5 The results are very similar to those obtainedwith glucose, and it is reasonable to conclude that the large value of K=/JEDfor catalysis by strong acid is a characteristic of the mutarotation of glucose.Protons of the hydroxyl groups equilibrate instantaneously in an aqueoussolvent and hence in the mutarotation the slow step will involve rupture ofan O-H bond in water and of an O-D bond in D20 with simultaneous ringopening in both cases.This results in a slower rate-determining step inD,O. It has been suggested36 that the reason for the mutarotation ofsugar osazones lies in the electron-displacement which takes place in theirchelate structure upon the action of solvent, i.e., there is a structural shiftfrom somewhere near state (11) (osazone derived from a hexose) towardsstate (12).Molecular-rotation studies of sugar derivatives have been rep~rted.~'Calculations have been made according to Klyne's method 38 of molecularrotations of the isomeric trehaloses 39 and, except for the values obtainedfor aa-trehalose, there is good agreement with experimental values.To provide support for earlier generalizations40 the action of alkali onsugar derivatives has been further studied.41 The effect of the presence ofcalcium on the alkaline degradation of 4-O-substituted glucose derivatives31 F.Shafizadeh, Abs. Amer. Chem. SOC., 132nd Meeting, 1957, 6D.32 2. I. Kuznetsova, Y e . D. Kaverzneva, and V. I. Ivanov, Izvest. Akad. Nauk33 J. M. Los and L. B. Simpson, Rec. Trav. chim., 1957, '96, 267.34 A. de Grandchamp-Chaudun, Compt. rend., 1957, 244, 1564.35 B. C. Challis, F. A. Long, and Y. Pocker, J., 1957, 4679.38 L.Mester and A. Major, J . Amer. Chem. Sac., 1957, 79, 3232.3 7 S. Yamana, Bu.11. Chem. SOC. Japan, 1957, 30, 203, 207.38 W. Klyne, Biochem. J.. 1950, 47, xli.39 J. StanCik, Nature, 1957, 1'79, 97.40 J. Kenner, Chem. and Ind., 1955, 727.4 1 W. M. Corbett, G. N. Richards, and R. L. Whistler, J., 1957, 11; G. N. Richards,S.S.S.R., Otdel. khim. Nauk, 1957, 655.ibid., p. 3222; J. Kenner and G. N. Richards, ibid., p. 3019298 ORGANIC CHEMISTRY.is to favour the reaction sequence (13) -+s(16), leading to D-gh.ICOiS0-saccharinic acids at the expense of competing reactions.42 There is tentativeevidence that the effect results partly from catalysis of the benzilic acidrearrangement (15) --+ (16).CHO CHz.OH CHI*OH COPHI I II I II +-OR+ I __t II I 1I IC(OH)*CH 2.0HCH 0H-C-OHG OC’OG OHO-C-HIIIIIH-C-OHHO-C-HLf--H-C-OR CH * H-C-ORH-C-OH CH2*OH H-C-OH H-C-OHCHP*OH CHa*OH CH2’OH(13) (14) (15) (16)Full details are now published 43 of the alkaline degradation of xylobioseand xylotriose.The major product is xyloisosaccharinolactone (17 is theacid), but three other lactones, probably of the acids (18), (19), and (20),were also detected. It is probable that these lactones arise by conversionCHz*OH CO,H CO,H C02HH-C-OHCH2C(OH)*CO,HCH,-OHCHZICH,*OH1III IH-C-OH II CH 2 IH-C-OHI IIICH 2H-C-OHof the biose and triose into xylose which is the reaction intermediate.The alkaline degradation involves a ‘‘ peeling ” reaction of the type,xylotriose _+ xylobiose xylose, in which each successive reducingsugar residue gives rise to acidic products with the simultaneous exposureof a new reducing group.The action of hot dilute sodium hydroxide oncellulose under oxygen-free conditions and short reaction times yieldsD-ghcoisosaccharinic acid (44%), lactic acid (4.3y0), formic acid (7--8%),acetic acid (<2y0), and a range of other acidic materials.44 In additionthere is an alkali-stable polysaccharide residue which on acid hydrolysisyields a- and 8-glucometasaccharinic acid (as the lactones) and a-D-gluco-saccharinic acid (?).45 It was concluded that during the degradation ofcellulose by oxygen-free alkali two competitive reaction sequences occur,namely, the ‘‘ degradation ” and the “ stopping ” reaction.The scheme 46represents the probable course of the reactions. The “ degradation ”reaction (21) (31) represents a progressive stepwise degradation from42 M. J. Blears, G. Machell, and G. N. Richards, Chem. and Ind., 1957, 1150.43 G. 0. Aspinall, Mary E. Carter, and (in part) M. Los, J., 1956, 4807; Chem. andInd., 1955, 1553; cf. R. L. Whistler and W. M. Corbett, J . Amer. Chem. SOC., 1956,78, 1003.44 G. N. Richards and H. H. Sephton, J., 1957, 4492.45 G. Machell and G. N. Richards, ibid., p . 4500.413 G. Machell, G. N. Richards, and H. H. Sephton, Chem. and Ind., 1957, 467OVEREND CARBOHYDRATES. 299the reducing end of the cellulose molecule, while the " stopping " reaction(21) __t (25) competes with this process but occurs at a much slower overallrate, chiefly owing to the mass-law effect in reactions (22) + (23) andCHO CHOC-OHCHI IIII II ICHO-Ci=OIIIIIC-OHHO-C-H 1 - 1 L - 'iH2 .__tH-C-O-(G), H-C-O-(G), H-C-O-(G),H- -C-OH H-C-OH + OH- H-C-OHCH,.OH CH,*OH CH2*OH(22 (23) (24)COSHCH*OHIIH-C-O-(G),IIH-C-OH ICH2*OH CH,*OH CHa*OHc=oHO-C-H1 IIIII7-OC-O-II1 - 1 - II +IIHO-C HO-CH-C-O-(G), H-C-O-(G), CHH-C-OH I1 H-C-OH H-C-OHCHZ-OH CH,*OH CHz*OHI ICH,*OH c=o CO,H C=O I I C(OH)*CH,*OH G OI+ IICHaOHCH,.OH CH*OHCHO H-C-OHIi - O I 1 I FH2 - CH2 tH-C-OH H-C-0 H I CH ,.OHICH,.OH CH2.0HII H-C-OH(32) (31) (30) CHz-OHCHO III1IH-C-OHHO-C-HH-C-O-(G),-,H-C-OHCH ,*OH(29)Furtherdegrad n.COzH I C=O --+ CH-OHICHSICHS(33) (34) (21) = Cellulose molecule of D.P.n + I(25) = Alkali-stable cellulose molecule(27) __t (28) which are almost certainly rate-determining.A full accounthas now been published 47 of the action of bases on methanesulphonyl estersof reducing sugars.4 7 D. C . C . Smith, J., 1957, 2690; Chern. and Ind., 1955, 92300 ORGANIC CHEMISTRY.Esters.-There has been considerable interest this year in the chemistryof sugar phosphates : the subject was reviewed re~ently.~8Several sugar phosphates have been obtained by enzymic syntheses, e.g.,erythrose 4-pho~phate~~ ribulose 5-~hosphate,~O ribulose 1 : 5-dipho~phate,~lxylulose 2-deoxyribose 1 : 5-dipho~phate,~~ lactose 1-phosphate,54 and octulose The effects of temperature, pH,enzyme concentration, phosphate, and starch concentration on the potatophosphorylase-catalysed synthesis of glucose l-phosphate have beenstudied.56Mannitol l-phosphate has been isolated from LactobaciZZus arabinosus. 57A substance containing glycerophosphate and ribitol phosphate residues alsooccurs in fresh cells of this organism.58A number of chemical syntheses and transformations of sugar phosphateshave been described.59 By a micromethod involving successive periodateand bromine oxidations of the ribitol cyclic phosphate (35),579 6O glyceric acid2 : 3-(hydrogen phosphate) (36) was formed: this on mild hydrolysis affordsglyceric acid 2- and 3-phosphate (37 and 38).The acids were shown byenzymic assay to have the D-configuration.6lPeriodate oxidation of D-ribose 3-phosphate and saponification of theO-formyl ester so produced yield D-erythrose 2-ph0sphate.6~ The mono-phosphates of 4-deoxy-~-erythronic acid (~-erytho-or~-dihydroxybutyricCHS'OH IIIH-C-OHH-C-OH __tH-F-o\do CHI*O' \OH(35)ICOLH COPHH-C-O*POIHs H-C-OH I I+ I CH2-O*P0,Hp - ICH **OH(1 P a 4 (4 parts)(37) (38)acid) have been synthe~ized.~~ From the anomeric mixture resulting (afterremoval of protecting groups) from the addition of triethylammoniumdibenzyl phosphate to 5-O-acetyl-~-ribofuranosyl bromide 2 : 3-carbonate4 8 A. B. Foster and W. G. Overend, Quart. Rev., 1957, 11, 61.49 M. Schramm and E. Racker, Nature, 1957, 179, 1349.5O D.B. McNair Scott and S. S. Cohen, Biochem. J., 1957, 65, 686.51 J. Mayaudon, A. A. Benson, and M. Calvin, Biochim. Biophys. Acta, 1957,23,342.52 J. Hurwitz and 33. L. Horecker, J. Bid. Chem., 1956, 223, 993; J. Hickmanand G. Ashwell, J . Amer. Chem. Soc., 1956, 78, 6209.53 H. L. A. Tam, Chem. and Ind., 1957, 562.54 J. E. Gander, W. E. Petersen, and P. D. Boyer, Arch. Biochem. Biophys., 1957,69, 85.55 E. Racker and E. Schroeder, ibid., 1957, 88, 241.56 T. Suzuki and I. Hamada, J . Ckem. SOC. Japan, 1956, 77, 1681.57 J. Baddiley, J. G. Buchanan, B. Carss, A. P. Mathias, and A. R. Sanderson,68 J. Baddiley, J. G. Buchanan, and G. R. Greenberg, ibid., 1957, 68, 51P.5Q Cf. A. GebauerovA and K. TomfGek, Chem. Zvasti, 1957, 11, 562.6o J.Baddiley and A. P. Mathias, J., 1954, 2723.6* H. S. Loring, L. K. Moss, L. W. Levy, and W. F. Hain, Arch. Biockem. Biophys-,Biochem. J., 1956, 64, 599.J. Baddiley, J. G. Buchanan, and B. Carss, J., 1957, 1869.C. Ballou, J . Amer. Chem. Soc., 1957, 79, 984.G. M Tener and H. G. Khorana, ibid., p. 437,1956, 65, 578OVEREND: CARBOHYDRATES. 301the crystalline dicydohexylammonium salt of a-D-sbofuranose 1 -phosphatewas obtained a8 the main product.66 This ester is identical with that ob-tained by enzymic phosphordysis of ribonucleosides. Alternative synthesesemploying 3 : 5-di-O-benzoyl-~-ribofuranosyl halides gave moderate yieldsof anomeric ribofuranose l-phosphates. A prehmhary account has ap-peared66 of the synthesis according to the annexed scheme of a-D-ribo-furanose 1 : 5-diphosphate (39).Substitution in this scheme of triethyl-ammonium tribenzyl pyrophosphate far triethylammonium dibenzylPhO-P-0.H FI 2 C a * C H 2 P hH O . H z C O CHzPh I * PhO IH HHO OH HO OH0HO IIReagents: I , (Pt10)~PoCl in C,H,N. 2, Mild alkali and then COClz in C,H,N. 3, HBr in AcOHand then triethylammonium dibenzyl phosphate. 4, (a) Pd-Hs, (b) Pt03-H,, (c) LiOH.phosphate led to 5-0-phosphoryl-a-~-ribofuranose l-pyrophosphate. Amixture of the 5-pyrophosphate (20-25%) and 5-triphosphate (10%) ofribose is formed by the action of phosphoric acid and dicyclohexylcarbodi-imide in aqueous pyridine on ribose 5-pho~phate.~~ After chromatographicseparation both compounds were converted into ribulose derivatives byphosphoriboisomerase.Reduction of D-ribose &phosphate by sodium borohydride gives D-ribitol5-ph0sphate.6~ cycloHexy1ammoniu.m salts have been employed extensivelyto obtain crystalline forms of sugar phosphates, e.g., from the l-phosphatesof a- and P-D-glucose, a- and P-D-galactose, a- and P-L-arabinose and a- andp-D-xylose.68 It has been shown that a-D-xylose l-phosphate is formedwhen tri-0-acetyl-l-bromo-D-xylose is heated in benzene with silver diphenylphosphate and the protecting groups are then eliminated,69 whereas reactionat room temperature leads to the p-an~rner.~~ 1 : 2-@isoPropyfidene-~-xylofuranose 3 : &phosphate (40) has been synthesized in excellent yield bya number of methods.'l Mild action of acid on compound (40) gave a good66 G.M. Tener, R. S . Wright, and H. G. Khorana, J . Amev. Ckem. SOC., 1956, 78,*t~ G. M. Tener and H. G. Khorana, Chem. and Ind.. 1957. 562.506; 1957, 79. 441.67 B. L. Horecker, J. Hurtwitz, and L. A. Heppel, J . Amev..Chem. SOC., 1957,79, 701.68 E. W. Putman and W. 2. Hassid, ibid., p. 5057.6s N. J. Antia and R. W. Watson, C h m . and Ind., 1956, 1143.70 Idem, &id., 1957, 600.71 J. G. Moffatt and R. G. Khorana, J. Amer. C h m . SOC., 1957, 79, 1194302 ORGANIC CHEMISTRY.yield of D-xylose 3 : 5-phosphate (41). D-Xylose 3-phosphate has beenprepared for the first time by alkaline hydrolysis of the cyclic derivative(M), followed by mild acidic hydrolysis of the products (42) and (43) andseparation on a resin column.71 Attempts to synthesize glucose l-methyl-phosphonate and isopropyl glucose l-methylphosphonate were unsuccessful. 72A galactosamine phosphate has been prepared which is presumably the6-phosphate. 73 A colour reaction has been devised which differentiatesbetween pentose &phosphate, free pentose, and other pentose esters. 74Complex mixtures of inorganic and organic phosphates can be separated bytwo-dimensional ionophoresis and chromatography on paper. 75Application of Hudson's isorotation rules to the CI- and P-l-phosphatesof L-arabinose, D-xylose, D-glucose, and D-galactose shows the 2A values(average value = 25,400) to be consistent with the first rule, but the 2Bvalues are greater than those of the corresponding methyl glycosides byca.9000 molecular rotation units.68 The changes in optical rotation ofneutral solutions of D-xylose 5-phosphate are due to the ready partialconversion of the ester into D-xylulose 5-ph0sphate.~~~ 76 In various buffersin the pH range 7-0-9.5, xylulose 5-phosphate is destroyed more rapidlythan ribulose 5-phosphate. Changes in pH have less effect than differencesH203p.0.H2cQ H0.H2;Q7 X = 'PO3H2H( 4 2 ) H O-CMe2 H O-CMe, (43)in the nature of the buffer.77 The alkaline decomposition of phosphateesters having a reducing group in the p-position has been examined.78Elimination occurs and glucose 3-phosphate gives glucometasaccharinic acid.Similarly ribose 3-phosphate affords a C,-saccharinic acid, e.g. :CH-O- CHO CO,H I-----+I - I1 - IICH-OHIIC-OH I1ICHOOH- C-OH -pots-IC H.O*PO ,H a C H*O*PO 32- CH CH 2 I R R R RAcid treatment of ribitol 1 (5)-phosphate gives ribitol3- and 2(4)-phosphate 6172 F.C. G. Hoskin, Canad. J. Chem., 1957, 35, 581.73 J. M. Merrick and S. Roseman, Abs. Amer. Chem. SOC., 131st Meeting, 1957, 12D.74 2. Dische and E. Landsberg, Biochim. Biophys. Acta, 1957, 24, 193.7 6 Cf. R. W. Watson and J. L. Barnwell, Chem. and Ind., 1955. 1089.77 E. Borenfreund and 2. Dische, Biochem. Biophys. Acda, 1957, 25, 215.7 8 D. Brown, F. Hayes, and (Sir) A. Todd, Chem. Ber., 1957, 90, 936.V. C . Runeckles and G. Krotkov, Arch. Biochem. Biophys., 1957, 70, 442OVEREND : CARBOHYDRATES. 303and 1 : 4-anhydroribit01.~~ Formation of the last compound, which is themain product of prolonged treatment, is probably best represented byprotonation of the ester oxygen atom followed by the electronic displace-ments shown, leading to an intramolecular nucleophilic substitution.Al-though D-ribitol5-phosphate was used in the experiments, the acid-catalysedphosphate migration leads to considerable or even com- , , - YH plete racemisation, and it is likely that the DL-form of they 2 CHZ-~-~;-OH anhydride is produced. D-Xylitol 5-phosphate is con-At higher pH (e.g., pH 4) normal hydrolysisof ribitol 1 (5)-phosphate occurs and ribitol is formed.793The stereochemical requirements for cyclic ester formation from sugarmonophosphates have been discussed. A general procedure has beendeveloped for formation of five- and six-membered cyclic phosphates fromesters containing suitably placed hydroxyl functions, dicyclohexylcarbodi-imide being the reagent.Five- and six-membered cyclic phosphates can bedifferentiated, since the former undergo further reaction with the carbodi-imide to form N-phosphorylureas. From the behaviour of hexopyranosel-phosphates (in CI conformation) with the carbodi-imide it was concludedthat cyclisation is possible when both the relation of a phosphate group tothe adjacent hydroxyl group is axial to equatorial (e.g., 44) or is equatorialto equatorial (e.g., 45) (both a- and @-glucose l-phosphate form 1 : 2-cyclicphosphates). If the phosphate and hydroxyl groups are both axial (e.g., 46)cyclisation will not occur (a-D-mannose l-phosphate does not form a cyclicphosphate on addition of the reagent). Glucose 6-phosphate reacts in thepyranose form and yields the 4 : 6-cyclic phosphate. The reagent convertsD-xylose &phosphate into the six-membered 3 : 5-cyclic phosphate, butD-xylose 3-phosphate gives a five-membered cyclic ester. Obviously the&phosphate has a furanose structure and the 3-phosphate is a pyranosederivative. When the formation of both five- and six-membered cyclicphosphates is possible, the former is favoured.H H+ o verted similarly into an anhydride but slightly moreslowly.The r81e of hexose phosphates in the synthesis of cellulose by AcetobacterThe preparation and properties of organosilyl derivatives of sugars havexy2inu.m has been studied.81been reported.S2( b ) J. Baddiley, J. G. Buchanan, and B. Carss, J., 1957, 4058.SOC.. 1957, 79, 430.7 9 (a) J. Baddiley. J. G. Buchanan, B. Carss, and A. P. Mathias, J . , 1956, 4583;8 0 H. G. Khorana, G. M. Tener, R. S. Wright, and J. G. Moffatt, J . ,4mer. Chem.81 M. Schramm, 2. Gromet, and S. Hestrin, Nature, 1957, 179, 28.82 F. A. Henglein, G. Abelsnes, H. Heneka, K. Lienhard, P. Nakhre, and K.Scheinost, Makromol. Chena., 1957, 24, 1304 ORGANIC CHEMISTRY.D-Glucose 3-sulphate has been prepared according to the followingscheme : 83 1 : 2-6 : 6-di-O-isopropylidene-a-~-glucofuranose 3-(methylsulphite) 4 [by Ca(Mn0,)J 3-(methyl sulphate) -+ (by aq. AcOH at40") [l : 2-5 : 6-di-O-~sopropylidene-c~-~-glucofuranose 3-sulphate] --+ D-glucose 3-sulphate.Fully nitrated derivatives of allitol, L-arabitol, xylitol, adonitol, iso-mannide, isosorbide, and isoidide have been prepared.85 The action ofdry pyridine on the hexanitrates of D-mannitol and D-galactitol removesselectively the 3( =4)-nitrate group, yielding the alcohol without inversion.85Alkaline hydrolysis of glucose nitrates has been examined. 86 With mono-nitrates the amount of nitrite released is relatively small, but increases asthe number of nitrate groups is increased (Le., increase in the Eco reaction).Substitution of free hydroxyl groups by ethylidene or methyl residuesincreases the extent of the Eco reaction. Hydrolysis of acetyl derivatives ofsugar mono- and di-nitrates results in preferential cleavage of the acetylresidues, but removal of acetate and nitrate does not occur in controlledsteps with monoacetates of sugar trinitrates. The 2-nitrate group of methyl4 : 6-O-ethylidene-ot-~-mannoside 2 : 3-dinitrate is removed preferentially(yielding the alcohol) by (i) sodium methoxide in cold methanol-chloroform,(ii) sodium iodide in acetone at loo", or (iii), best, by sodium nitrite in boilingaqueous ethanol.*'Partial esterification of methyl 4 : 6-O-benzylidene-a-~-glucoside inpyridine with chlorides of carboxylic and sulphonic acids gives mainly the2-monoester. Likewise sulphonic anhydrides give the 2-monoester, butcarboxylic anhydrides give the 3 - e ~ t e r . ~ ~ For the glycoside the relativereactivity at positions 2 and 3 depends on the number of protons (eitherproduced by external addition or by release during the reaction) in thereaction medium. The results of this study are not in agreement with thegeneralization 89 that 2-hydroxyl groups are more reactive than othersecondary hydroxyl groups, especially in alkaline media.Amino-sugars.-N-Acetylglucosamine and N-acetylgalactosamine occurin a polysaccharide isolated from B. s ~ b t i l i s , ~ ~ and fucosamine is a componentof a polysaccharide from Chromobacterium v i o l a c e ~ r n . ~ ~ A growth-factor forL. biJidus var. Pennsylvanicus has been identified as ethyl N-acetyl-p-D-glu~osaminide.~2 " Trealoseamine," a new amino-sugar produced by astreptomycete, has been isolated. 93 Acid hydrolysates of chondroitinsulphate from hyaline cartilage contain an amino-sugar which is probablytal~samine.~~ Amino-sugars have been detected in hydrolysates of soya-bean83 A. B. Foster and E. B. Hancock, J., 1957, 968.84 A. B. Foster, E. B. Hancock, W. G. Overend, and J. Robb, J., 1956, 2589.85 L. D. Hayward, Abs. Amer. Chem. SOC., 132nd Meeting, 1957, 15D.86 D. O'Meara and D. M. Shepherd, J., 1957, 3377.87 J. Honeyman and T. C . Stening, ibid., p. 2278.88 R. W. Jeanloz and D. A. Jeanloz, J . Amer. Chsm. Soc., 1957, 79, 2579.89 J. M. Sugihara, Adv. Carbohydrate Chem., 1953, 8, 1.90 N. Sharon, Nature, 1957, 179, 919.91 D. A. L. Davies, ibid., 1957, 180, 1129.92 S. Pope, R. M. Tomarelli, and P. Gyorgy, Arch. Biockem. Bioghys., 1957, 68, 362.93 F. Arcamone and F. Bizioli, Gazzetta, 1957, 87, 896.94 H. Muir, Biochem. J., 1957, 65, 33POVEREND : CARBOHYDRATES. 305g l y ~ i n i n . ~ ~ The structure of muramic acid is 3-O-c+ethoxycarbonyl-~-glucosamine. 96 The dimethylamino-sugar (47) (amosamine) occurs in theantibiotic ame~etin.~' Mycosamine has structure (48).g8 The D-configur-ation is assigned to but the remainder of the stereochemistry is stillbeing investigated. The neobiosamine moiety of both neomycin B and Cconsists of a diaminohexosido-pento~e.~~Amino-sugar chromatograms developed with weakly basic or acidicsolvents require cautious interpretation.lO0 Methods are available for theseparation of talosamine from other 2-amino-hexoses lo1 and for the deter-mination of 10-100 pmg. of hexosamine.1o2 A determination of hexos-amines in conjunction with electrophoresis on starch has been outlined.lo3A review of amino-sugars has been published.lWW. G. 0.P. BLADON.R. C. COOKSON.L. CROMBIE.A. G. QAVIES.R. F. GARWOOD.T. G. HALSALL.W. G. OVEREND.K. SCHOFIELD.S. F. SMITH.G. H. WILLIAMS.G. T. YOUNG.P. B. D. DE LA MARE.0s B. N. Gladyshev, Doklady Akad. Nauk S.S.S.R., 1957, 112, 291.g6 L. H. Kent, Biochem. J., 1957, 67, 5P.07 C. L. Stevens, R. J . Gasser, T. K. Mukherjee, and T. H. Haskell, J . Amer. C k m .88 D. R. Walters, J . D. Dutcher, and 0. Wintersteiner, ibid., 1957, 79, 5076.99 K. L. Rinehart, P. W. K. Woo, A. D. Argoudelis, and A. M. Giesbrecht, ibid.,Soc., 1956, 78, 6212.p. 4567.100 D. H. Leaback and P. G. Walker, Biochem. J., 1957, 6'7, 22P.l01 M. J. Crumpton, Nature, 1957, 180, 605.102 D. Exley, Biochem. J., 1957, 67, 52.103 0. W. Newhaus and M. Letzring, Analyt. Chem., 1957, 29, 1230.104 R. Kuhn, H. H. Baer, W. Bister, R. Brossmer, A. Gauhe, H. J. Haas, F. Haber,G. Kriiger, T. Tiedemann, and D. Weiser, Angew. Chem., 1957, 89, 23

ISSN:0365-6217    

DOI:10.1039/AR9575400147

出版商:RSC    

年代:1957

数据来源: RSC

摘要:

BIOLOGICAL CHEMISTRY.1. INTRODUCTION.THIS year’s Report deals with some interesting and important aspects offour major fields in biological chemistry, namely enzymes , amino-sugars ,purines and pyrimidines, and antibiotics.Use of isotopes in the study of the mechanism of reactions in purechemistry has proved most fruitful, and the application of isotopes to enzymereactions has been no less so. In fact isotopic methods have led to a greaterunderstanding of the mechanisms and the intermediates of enzyme reactionsand to new and unsuspected types of specificity. In the amino-sugar field,much progress has been made in elucidating the biological chemistry of theso-called “ sialic acids ”, which are now known to be derivatives of neur-aminic acid. The latter, a compound of glucosamine and pyruvic acid, isof wide occurrence in animals as a component of carbohydrate-proteincomplexes and is of considerable interest from the biological viewpoint sinceit is believed to function as a blood-cell receptor for the influenza virus.Knowledge on the biosynthesis of the purine and pyrimidine ring systems isadvancing very rapidly and enzyme systems have now been found which areable to carry out many, but not all, of the reactions involved.The reporton purine and pyrimidine biosynthesis does a great deal to sort out andpresent a clear picture of this rapidly developing subject.The subject of the biosynthesis of antibiotics takes us into the field ofmicrobiological chemistry. It is now becoming clear that several antibioticsare biosynthesised from L-amino-acids, and since these antibiotics containthe D-forms of these acids, interesting problems of optical inversion are in-volved.Much progress is also being made in elucidating the mode of bio-synthesis of antibiotics, such as streptomycin, which are derived fromsugars, and it is now becoming clear that these and aromatic antibiotics,including the tetracyclines, can be synthesised by micro-organisms fromsuch simple compounds as acetate.R. T. W.2. THE MECHANISM OF ENZYME ACTION STUDIED WITH ISOTOPES.*THE application of isotope methods to enzymic reactions has yielded in-formation which is broadly of two types. In the first place considerableinsight has been gained into the nature of reaction mechanisms and theformation of intermediates.Secondly, many new examples of specificity* Abbreviations used : adenosine diphosphate, ADP; adenosine triphosphate, ATP;adenosine triphosphatase, ATPase ; adenylic acid, AMP; coenzyme A, CoA; diisopropylphosphonofluoridate, DFP; diphosphopyridine nucleotide, DPNC; reduced diphos-phopyridine nucleotide, DPNH ; guanosine diphosphate, GDP; guanosine triphosphate,GTP; triphosphopyridine nucleotide TPNf; reduced triphosphopyridine nucleotide,TPNH ; uridine diphosphate, UDP ; uridine triphosphate, UTPGIBSON ENZYME STUDIES WITH ISOTOPES. 307have been revealed, in some cases of unsuspected type; examples will befound in the discussion of the appropriate enzyme. The subject of inter-mediates and mechanisms needs brief introduction ; after that attentionwill be given to individual enzymes, and a short final section will describerecent work on the structure of active centres in enzymes.that group-transfer reactions catalysed by enzymes are substitution reactions, usuallynucleophilic, occurring a t the surface of the enzyme. Three mechanismswere distinguished, two of which involve direct displacement of a groupfrom one substrate to another (single displacement) :Reaction Mechanisms.-It was suggested by KoshlandA-B + C -=A + &CIn the third (double displacement) the group is first transferred to theenzyme, and then to another substrate:A-B + enzymeC + B-enzymeA + B-enzymeC--8 + enzymeThese reactions are very possibly brought about by concerted acid-basecatalysis.2 The hypothesis was originally suggested to cover hydrolytic,phosphorolytic, kinase, and other similar reactions,la but it is clear thatwith slight modification and extension it will apply to a large number ofenzymic reactions. Isotopes have been applied in two ways to test Kosh-land's ideas; first by the study of the so-called exchange reactionscatalysed by many enzymes, and secondly by determining the point a t whicha substrate is cleaved by the enzyme.Exchange reactions.An immediate consequence of the application oftracer methods to enzymic reactions was the recognition that a number ofenzymes catalyse exchange reactions of the typeA-B + B* A-B* + BThe significance of such reactions in relation to the overall mechanism hasbeen carefully examined by Koshland.lb*c It is often possible to concludethat an exchange reaction occurs with intermediate formation of an enzyme-substrate compound, but this is not always true.Considerations of speci-ficity I b and kinetics lC can sometimes be applied to decide whether such acompound is formed; for example, kinetic studies of exchange reactionsshow that 5'-nucleotidase does not form an enzyme-phosphate inter-mediate.lc If the reaction is to be properly interpreted it is obviouslyimportant to establish what other substrates must be present for an exchangeto occur; however the use of insufficiently purified enzymes has at timesled to erroneous conclusions, for instance with glutamine synthetase3 anda~eto-CoA-kinase.~1 Koshland lC has tabulated about twenty-five instances1 D.E. Koshland, jun., ( a ) Biol. Rev. Camb. Phil. SOC., 1953, 28, 416; (b) in " Mech-anism of Enzyme Action," Johns Hopkins Press, Baltimore, 1954, p. 608; (c) Discuss.Faraday Soc., 1955, 20, 142.2 Idem, ( a ) J . Cellular Cotnp. Physiol., 1956, 47, Suppl. 1, 217; (b) Biochim. Biophys.Acta, 1957, 25, 219.3 G. C. Websterand J. E. Varner, J . Amer. Chena. SOC., 1954, 76. 633.4 M. E. Jones, F. Lipmann, H. Hilz, and F. Lynen, ibid., 1953, 75, 3286.6 F. Lipmann, Science, 1954, 120, 855308 BIOLOGICAL CHEMISTRY.in which the existence of exchange reactions has been investigated; otherswill be mentioned below.Point of cleavage. The point at which nucleophilic attack occurs can bedetermined from a knowledge, among other things, of the bond which isbroken.lb This can usually be determined unequivocally by use of isotopes.It has been found, for instance, that in many kinase reactions ATP is split atthe terminal 0-P bond, in agreement with nucleophilic attack by thesubstrate on the terminal phosphorus atom of ATP.l* From a study of thebonds split in certain hydrolytic and transfeF reactions, Koshland la* b hassuggested two rules for detennining the point of cleavage, from a con-sideration either of relative chemical reactivities, or of the substratespecificity shown by the enzyme.As will be seen in individual cases, theserules are amply supported by experiment.Venaes-land and her co-workers have shown that in oxidations in which DPN+ ishydrogen-acceptor there is direct transfer of one hydrogen (or deuterium)atom from substrate to dinucleotide.Most of this work has been brieflyreviewed.6~7 Direct hydrogen transfer has been shown for alcohol (yeast 8and liver 9), aldehyde,B glucose,l0 lactic,ll triose phosphate,12 malic 13 andglutamic 9 dehydrogenases, and a bacterial p-hydroxysteroid dehydrogen-ase.14 Of the nine enzymes which have been investigated, only dihydro-orotic dehydrogenase15 did not catalyse direct hydrogen transfer; but inthis case there was some indication of a two-stage reaction involving a flavinprosthetic group. The direct transfer of deuterium catalysed by alcoho€and lactic dehydrogenases has been used to show that in DPNH the extrahydrogen atom is attached to position 4 of the nicotinamidc ring.I6 It hasalso been found that hydrogen is t r a n s h e d directly in the reactionscatalysed by TPN+-linked isocitric dehydrogenase l7 and transhydmgenase ; 18with the latter the possibility that the reaction occurred by phosphatetransfer from TPNH to DPN+ was r u l e d .~ u t ~ ~ by use of [114C]DPN+.A further important result has been the discovery that the enzymicreduction of DPN+ is stereospecific. There are two possible boat forms ofthe reduced nicotinamide ring of DPNH; 7b+9 the ttvo hydrogen atoms inposition 4 can be distinguished as, in each form, one of them lies in theBiological Oxidations.-Reactions involving DPN+ and TPN+.6 B. Vennesland and F. H. Westheimer, ref. lb, p. 357.7 I3.Vennesland, (Q) Discuss, Faraday SOC., 1955, 28; 240; (b) J. Celldar Comp.8 H. Harvey, E. E. Conn, B. Vennesland, and I:. 11. Westheimer, J . Biol. Chem.,9 H. R. Levy and B. Vennesland, ibid., 1967, 228. .".10 H. R. Levy, F. A. Loewus. and B. Vennesland, zbad., 1956, 222, 685.11 F. A. Loewus, P. Ofner, H. F. Fisher, I?. H. Westheimer, and B. Vennesland, ;bid.,12 F. A. hewus, H. R. Levy, and B. Vennesland, ibid., 1956, 223, 589.13 F. A. hewus, T. T. Tchen, and B. Vennesland, ibid., 1986, 212, 787.1' P. Talalay, F. A. Loewus, and B. Venmslaod, ibid., p. 801.16 J. L. Graves and B. Vennesland, ibid., 1957, 226, 307.16 M. E. Pullman, A. San Pietro, and S. P. Colowick, ibid., 1954, 206, 129; F. A.Loewus, B. Vennesland, and D. L. Hams, J. Anzev.Chenz. Soc., 1055, 77, 3391.1 7 S. Englard and S. P. Colowick, J. Bid. Ghem., 1957, 226, 1047.1 8 A. Sari Pietre, N. 0.. Kaplan, and S. P. Colowick, ibid., 1955, 212, 941;19 N. 0. Kaplan, S. P. Colowick, L. J. Zatman,.andM. M. Ciotti, ibid., 1853, 205, 31.Physiol., 1956, 47, Suppl. 1, 201.1953, 283, 687.1053, 202, 699GIBSON ENZYME STUDIES WITH ISOTOPES. 309equatorial position. The stereospecificity exhibited by the enzymes studiedhas been explained by assuming that each enzyme will only use the hydrogenatom in the equatorial plane of one form of the ring and not the other.0It has also been suggested that hydrogen transfer is facilitated betweendehydrogenases with opposite specificity. 7b, The actual steric configur-ations of the two forms is unknown, but enzymes which produce thesame form as yeast alcohol dehydrogenase are said to show a-specificity,other enzymes being @-specific.Liver alcoh01,~ aldeh~de,~ lactic,ll andmalic l3 dehydrogenases are a-specific; all the other dehydrogenases, and inaddition p-glycerophosphate dehydrogenase and transhydrogenase,18 are@-specific. Even in reactions where hydrogen is not transferred directlythere may be a greater or lesser degree of specificity shown for one formof DPNH, as with DPNH-cytochrome c reductase 20*21 and diaphorase,22both of which show p-specificity. However milk xanthine oxidase is non-specific. 7 b 3 21In addition to the specificity shown for DPNH, yeast alcohol dehydrogen-ase shows steric specificity in the removal of hydrogen from its substrate.It has been found that the monodeuterated ethanol produced when[alde/~,yde-~H]acetaldehyde is reduced by DPNH is stereochemically pure,as shown by enzymic re-oxidation and by Walden inversion which occursduring reaction with toluene-9-sulphonyl chloride.6, 23 The absolute con-figuration of this material has recently been determined.=Other oxidative enzymes. The reactions catalysed by oxidative enzymeswhich utilise molecular oxygen have been classified by Mason 25 in a reviewwhich includes much of the isotopic work on these enzymes.The use of[18O]oxygen and [l*O]water has shown that oxygen transferases, such ascatechol oxidase 26 and a bacterial lactic oxidative de~arboxylase,~~ catalysethe direct incorporation of molecular oxygen into their substrates, whileelectron transferases, such as xanthine ~ x i d a s e , ~ ~ notatin,28 and uricase 29catalyse the removal of hydrogen. The investigations of notatin and uricaseare of interest in that it was necessary to determine the reaction products aswell as the mechanism.Aromatic and steroid hydroxylations are of anintermediate type. In all but one of the hydroxylations investigated theincorporated oxygen atom is derived from molecular oxygen and not fromwater; this is true of llp-hydroxylation of steroids 30 as well as of 6p-,20 G. R. Drysdale and M. Cohn, Biochim. Biophys. Acta, 1956, 21, 397; C. Frieden,ibid., 1957, 24, 241.21 G. R. Drysdale, Fed. PYOC., 1957, 16. 175.22 M. W. Weber, N. 0. Kaplan, A.San Pietro, and F. E. Stolzenbach, J . Bid.23 F. A. Loewus, I;. H. Westheimer, and €3. Vennesland, J . Amer. Chem. SOC., 1953,p4 H. R. Levy, F. A. Loewus, and B. Vennesland, ibid., 1957, 79, 2949.25 H. S. Mason, Science, 1956, 125, 1185.a6 0. Hayaishi, M. Katagiri, and S. Rothberg, J . Amer. Chem. SOL, 1955, 77, 5450.27 0. Hayaishi and W. B. Sutton, ibid., 1957, 79, 4809.28 R. Bentley and A. Neuberger, Biochem. J., 1949, 45, 584.29 Idem, ibid., 1954, 52. 694.30 M. Hayano, M. C. Lindberg, R. I. Dorfman, J. E. H. Hancock, and W. von E.Doering, Arch. Biochem. Biophys., 1955, 59, 529; M. L. Sweat, R. A. Aldrich, C. H. deBrun, W. L. Fowlks, L. R. Heiselt, and H. S. Mason, Fed. Proc., 1.956, 15. 367: P.Talalay, Physiol. Rev., 1957, 37, 362.Chew$., 1957, 227, 27.75, 5018310 BIOLOGICAL CHEMISTRY.17a-, and 2l-hydroxylation~,~l the conversion of squdene into lanosterol,32certain aromatic hydro~ylations,~~ and the reaction catalysed by phen01ase.~3In the hydroxylation of salicylic acid catalysed by peroxidase the in-corporated oxygen atoms also originate from oxygen and not from water.=The exception is the 6-hydroxylation of nicotinic acid by Pseudomonas$uorescens, in which the oxygen atom comes from water.35 In the l l g -hydroxylation of I I-deoxycorticosterol it has also been shown that nodeuterium from [2H]water gets into a stable position in the ring.36 Themechanism of these reactions is unknown, although that suggested forphenolase 25933 may have wider application; however, recent work 37indicates that in one hydroxylation a t least, more than one enzyme is in-volved.Hydrolytic Enzymes.-Chymotrypsin catalyses an incorporation ofoxygen from the medium into the acid product of hydroly~is,~~ or from thecarbonyl group of this product into water.39 Furthermore this exchangefollows Michaelis-type kinetics, and the value of the Michaelis constant forexchange is the same as the dissociation constant for the acid-enzymecomplex, determined from inhibition studies 39 or by equilibrium dialy~is.~oChymotrypsin also catalyses the incorporation of [15N]glycine amide intobenzoyltyrosylglycine amide,41 and papain catalyses a similar exchange of[15N]ammonia into benzoylglycine amide.42 The exchange reactions ofchymotrypsin are consistent with the formation of an acyl-enzyme com-pound.There is isotopic 43 and non-isotopic 44 evidence for the formationof an acyl-enzyme compound of acetylcholinesterase, and this has been usedto explain the fact that during the hydrolysis of acetylcholine both carboxyloxygen atoms of acetate can be exchanged with the medium.45 The cleavagepoint of a number of esters by chymotrypsin has been determined by usingsubstrate labelled with l80 in the carbonyl or alkoxyl oxygen atoms.46 Ineach case the acyl-oxygen bond was broken. The same bond of acetylcholineis broken by a~etylcholinesterase,4~ as shown by hydrolysis in [180]water.These enzymes illustrate one of Koshland's rules to determine the point ofcleavage; the other rule is illustrated by invertase?' which cleaves sucrose31 M.Hayano, A. Saito, D. Stone, and R. I. Dorfman, Biochim. Biophys. Acta,32 T. T. Tchen and K. Bloch, J . Biol. Chem., 1957, 226, 931.33 H. S. Mason, W. L. Fowlks, and E. Peterson, J . Amer. Chem. SOC., 1955,77, 2914.34 H. S. Mason, I. Onoprienko, K. Yasunobu, and D. Buhler, ibid., 1957, 79, 5578.35 A. L. Hunt, D. E. Hughes, and J. M. Lowenstein, Biochem. J., 1957, 66, 2 ~ .36 M. Hayano and R. I. Dorfman, J . Biol. Chem., 1954, 211, 227.37 S. Kaufman, Biochim. Biophys. Acta, 1957,23, 445; J . Biol. Chem., 1957,226, 511.38 D. B. Sprinson and D. Rittenberg, Nature, 1951, 167, 484; D. G. Doherty and9s M. L. Bender and K. C. Kemp, ibid., 1957, 79, 116.40 F. Vaslow, Biochim. Biophys. Acta, 1955, 16, 601; Compt.rend. Trav. Lab.*1 E. B. Johnston, M. J. Mycek, and J. S. Fruton. J . Biol. Chem., 1950, 187, 205.O2 Idem, ibid., 1950, 185, 629.43 S. S. Stein and D. E. Koshland, jun., Arch. Biochem. Biophys., 1953, 45, 467.44 I. B. Wilson, Biochim. B.io$hys. Acta, 1951, 7, 520; D. Nachmansohn and I. B.45 R. Bentley and D. Rittenberg, J. Amer. Chem. Soc., 1954, 76, 4883.48 M. L. Bender and K. C. Kemp, ibid., 1957, 79, 111.4 7 D. E. Koshland, jun., and S. S. Stein, J . Biol. Chem., 1954, 208, 139.1956, 21, 381.F. Vaslow, J . Amer. Chem. Soc., 1952, 74, 931.Carlsberg, SBr. Chim., 1956, 30, 45.Wilson, Adv. Enzymology, 1951, 12, 259GIBSON ENZYME STUDIES WITH ISOTOPES. 31 1at the fructose-oxygen bond, and @-amylase,48 which cleaves amylasebetween the C(,)-atom of maltose and the bridge oxygen atom.When urease acts on urea in [180]water, not more than one atom of l80is found in the carbon dioxide formed, showing that the product of theenzymic reaction is carbamic acid, and not carbonic acid or carbon dioxideand ammonia.49 The small incorporation of [15N]amm~nia into ureacatalysed by this enzyme has been satisfactorily explained as due to re-synthesis of urea from carbamic acid and ammonia.50In experiments with [IsO]water it was found that alkaline phosphatasecleaves the 0-P bond in glucose l-phosphate,%, 51 adenosine-3' and -5'ph0sphates,5~ ~-glycerophosphateJs2 butyl thiophosphateJ2" and phenylphosphate.2a Koshland 2a uses this specificity as an argument against thetheory that enzymes act by simply providing energy to activate the substrate.The same bond of glucose l-phosphate is broken by acid pho~phatase.~~Alkaline phosphatase also catalyses oxygen exchange between water andphosphate, but not between water and phenyl phosphate.52 By usingmixtures of the univalent and the bivalent anion of P-glycerophosphate inwhich one or other species was labelled with 32P, it was shown that the formattacked by alkaline phosphatase was not the bivalent anion; 53 otherconsiderations show that it is probably the un-ionised form which ishydrolysed.In one of the first experiments with [180]water, it was shownthat bacterial acetylphosphatase splits the 0-P bond." Muscle acetyl-phosphatase does not catalyse any exchange of [l4C]acetate or [32P]pho~phatewith acetylpho~phate.~~ The results are consistent in all these cases withnucleophilic attack on the phosphorus atom.The point of cleavage of ATP by lobster-muscle ATPase 56 and bymyosin 57,58 was shown with [180]water to be the terminal 0-P bond.Potato apyrase also splits the terminal 0-P bond of both ATP and ADP.59Lobster muscle catalyses an exchange of oxygen between water andphosphate,56 but myosin does not catalyse this reaction in either direction.57These is no exchange of r2P] between phosphate and ATP in the presenceof myosin alone,59 but fresh actomyosin does catalyse such an exchange.60In an investigation into the role of water in the myosin-ATPase reaction, itwas found with the aid of [14C]methanol that the rate of hydrolysis of ATPwas at least 100 times as great as the rate of methanolysisJ61 although theratio of the rates of non-enzymic hydrolysis and methanolysis of a number4 8 M.Halpern and Y . Leibowitz, Bull. Res. Council Israel, 1957, 6, A , 131.40 J. H. Wang and D. A. Tarr, J . Amer. Chem. SOC., 1955, 77, 6205.5 0 G. B. Kistiakowsky and W. E. Thompson, ibid., 1956, 78, 4821.51 M. Cohn, J . Bid. Chem.. 1949, 180, 771.52 S. S. Stein and D. E. Koshland, jun., Arch. Biochem. Biophys., 1952, 39, 229.54 R. Bentley, J . Amer. Chem. Soc., 1949, 71, 2765.6 5 I. Harary, Fed. Proc., 1957, 16, 192.5 8 D. E. Koshland, jun., and E. Clarke, J . B i d . Chem., 1953, 205, 917.5 7 D. E. Koshland, jun., 2. Budenstein, and A. Kowalsky, ibid., 1954, 211, 379.5 8 M. Cohn, Biochim.Biophys. Ada, 1956, 20, 92.59 M. Cohn and G. A. Meek, Biochern. J., 1957, 06, 128.61 D. E. Koshland, jun., and E. B. Herr, jun., J . Bid. Chem., 1957, 228, 1021.A. F. Reid and J. H. Copenhaver, Biochim. Biophys. Ada, 1957, 24, 14.G. Ulbrecht and M. Ulbrecht, Biochim. Bio9hys. A d a , 1957,25, 100; G. Ulbrecht,M. Ulbrecht, and J. H. Wustrow, ibid., p. 110312 BIOLOGICAL CHEMISTRY.of phosphate esters including ATP was only 04-26. This was taken asevidence for a specific site of binding of water to myosin.Phosphory1ases.-One of the first exchange reactions to be demonstratedwas the incorporation of [32P] from [32P]phosphate into glucose 1-phosphatecatalysed bv sucrose phosphorylase.62 The enzyme also catalyses theincorporation of [14C]fructose into sucrose.63 The point of cleavage ofglucose l-phosphate is the glucose-oxygen bond. 51 The overall reaction isa good example of Koshland's double-displacement mechanism.lb, 62 Maltosephosphorylase 64 and potato and muscle phosphorylase 65 do not catalyse anexchange between phosphate and glucose l-phosphate, although the thirdenzyme causes cleavage of the glucose-oxygen b0nd.~1Pyrophosphory1ases.-Studies with [32P]-pyrophosphate have shown thatDPN 66 and GDP-mannose 67 pyrophosphorylases attack their substratesbetween the two phosphorus atoms.The latter enzyme also catalyses theincorporation of 32P from pyrophosphate into GTP; 68 a similar reaction iscatalysed by UDP-glucose pyrophosphorylase if sugar phosphate is present .69Dehydrases.-Fumarase adds [*H]water to fumarate in a stereospecificmanner; 70' 71 however the incorporation of deuterium from [2H]water intomalate 70 was due entirely to reversal of the overall reaction.71 There wasalso no isotope effect of deuterium on the overall reaction rate.71 Frommagnetic resonance measurements of [2H,]malate formed in this manner itwas concluded that the hydrogen and hydroxyl groups added to fumarateare cis to the carboxyl groups.72When aconitase acts on isocitrate in [2H]water, less deuterium is foundin the citrate formed than when the enzyme acts on a~onitate.'~ It wasconcluded that aconitate is not an obligatory intermediate in the con-version of isocitrate into citrate.It has also been found that aconitase isspecific for one of the hydrogen atoms in the a-carbon atom of citrate; thatis, it attaches and removes the same at0m.1~Dehydrogenases.-The mechanism of the reaction catalysed by triosephosphate dehydrogenase has been well established by non-isotopicmethods.74 The isotopic evidence is in complete accord with the formationof an intermediate acyl-S-enzyme compound.Yeast or muscle dehydrogen-ase catalyses the exchange of 32P between phosphate and the l-phosphategroup of 1 : 3-diphosphoglyceric acid in the absence of DPN, and the62 M. Doudoroff, H. A. Barker, and W. 2. Hassid, J . Biol. Chem., 1947,168, 717, 725.63 H. Wolochow, E. W. Putman, M. Doudoroff, W. 2. Hassid, and H. A. Barker,64 C. Fitting and M. Doudoroff, ibid., 1952, 199, 153.65 M. Cohn and G.T. Con, ibid., 1948, 175, 89.66 A. Kornberg and W. E. Pricer, jun., ibid., 1951, 191, 535.67 A. Munch-Petersen, Arch. Biochem. Biophys., 1955, 55, 592.66 Idem, Acta Chem. Scand., 1956, 10, 928.E. F. Neufeld, V. Ginsburg, E. W. Putman, D. Fanshier, and W. 2. Hassid,7 0 H. F. Fisher, C. Frieden, J. S. McKee, and R. A. Alberty, J . Amer. Chcm. SOC.,7 1 R. A. Alberty, W. G. Miller, and H. F. Fisher, ibid., 1957, 79, 3973.72 T. C. Farrar, H. S. Gutowsky. R. A. Alberty, and W. G. Miller, ibid., p. 3978.73 J . F. Speyer and S. R. Dickman, J . Biol. Chem., 1956, 220, 193.74 E. Racker and I. Krimsky, ibid., 1952, 198, 731; H. L. Segal and P. D. Boyer,ibid., 1953,204, 265; 0. J. Koeppe, P. D. Boyer, and M. P. Stulberg, ibid., 1956,219,569.ibid., 1949, 180, 1239.Arch.Biochem. Biophys., 1957, 69, 603.1965, 77, 4436GIBSON: ENZYME STUDIES WITH ISOTOPES. 313exchange is inhibited by thiol reagents.V6 Also, when phosphoglycer-aldehyde is oxidised in [18O]water, one atom of l80 is found in the sameposition of diphosphoglycerate. 769 77More radioactivity is found in isocitrate than in oxalosuccinate whenisocitric dehydrogenase acts on a-oxoglutarate, TPNH, and [14C]carbondioxide; and after oxidation of [14C]isocitrate in the presence of a pool ofoxalosuccinate very little radioactivity was found in the It wasconcluded that oxalosuccinate is not an intermediate in the overall reaction.There is some evidence that heart-muscle succinic dehydrogenase catalysesan exchange of deuterium between [2H]water and succinate,79* 80 inwhich the methylene hydrogen atoms of the succinate become randomlylabelled.8*Kinases.-Evidence against an enzyme-phosphate intermediate is pro-vided in the pyruvate kinase 769 77 and acetate kinase 779 81 reactions by thelack of exchange of [14C]-labelled substrate with the phosphorylated product.There is similar evidence against an acyl-enzyme intermediate in the latterreaction.81 Neither enzyme catalyses any exchange of oxygen betweenwater and the phosphorylated product or ADP.76s In both reactions, andin the creatine kinase reaction, the terminal 0-P bond of ATP is split; 77the same bond is attacked by m y ~ k i n a s e . ~ ~ These reactions probablyinvolve direct nucleophilic attack by the acceptor molecule on the terminalphosphorus atom of ATP.77 The 0-P bond of diphosphoglycerate is alsoattacked by phosphoglycerate kinase.57 When hexokinase acted on ATPand glucose in [180]water, no isotope was found in either the glucose 6-phosphate or the ADP.57It was a t first thought that aceto-CoA-kinase would catalyse the in-corporation of [32P]pyrophosphate into ATP in the absence of acetate: andthe formation of an enzyme-AMP intermediate was po~tulated.~, However,Berg g2 found with purer materials that this exchange is dependent on thepresence of acetate, and obtained good evidence that acetyl adenylate is anintermediate in the reaction. Work with l80 showing that oxygen from thecarboxyl group of acetate is incorporated into AMP is in agreement with theformation of this anhydride.= Studies on exchange reactions with abacterial enzyme support Berg’s view of the mechanism for that prepar-ation.= The incorporation of pyrophosphate into ATP catalysed by anenzyme activating fatty acids has also been explained in terms of anhydridef o r r n a t i ~ n .~ ~ When the tryptophan-activating enzyme acted on ATP ,tryptophan, and hydroxylamine in [lsO]water, l80 was found only in the75 P. Oesper, J . Biob. Chem., 1954, 207, 421.7 6 P. D. Boyerand W. H. Harrison. ref. l b , p. 658.7 7 W. H. Harrison, P. D. Boyer, and A. B. Falcone, J . Biol. Chem., 1955, 215, 303.78 G. Siebert, M. Carsiotis, and G. W. E. Plaut, ibid., 1957, 226, 977.7 9 E. 0. Weinmann, M. G. Morehouse, and R. J. Winzler, ibid., 1947, 168, 717.80 S.Englard and S. P. Colowick. ibid., 1956, 221, 1019.81 I. A. Rose, M. Grunberg-Manago, S. R. Korey, and S. Ochoa, ibid., 1954,211, 737.82 P. Berg, J . Amer. Chem. Soc., 1955, 77, 3163; J . Biol Chem., 1956, 222, 991,83 P. D. Boyer, 0. J. Koeppe, and W. W. Luchsinger, J . Amer. Chem. SOC., 1956,84 M. A. Eisenberg, Biochim. Biophys. Actn, 1957, 23, 327.8 5 W. P. Jencks and F. Lipmann, J . Biol. Chem., 1957, 225, 207.1018.78, 356314 BIOLOGICAL CHEMISTRY.phosphate group of AMP; 86 this agrees with the hypothesis that an acyladenylate is an intermediate. 87 These reactions all involve nucleophilicattack by the carboxyl group of the substrate on the inner phosphorus atomof ATP.From astudy of the conditions under which this enzyme promotes exchange re-actions between phosphate and ATP, ADP and ATP, and succinate andsuccinyl-CoA, Kaufman 88 postulated the intermediate formation of enzyme-bound phosphoryl-CoA.The transfer of l80 from [180]phosphate tosuccinate during the overall reaction 5 7 9 8 9 is at least compatible withKaufman’s mechanism. It was later found that this incorporation of 180proceeds much more rapidly than the incorporation of 32P from[32P]phosphate into ATP catalysed by the same enzyme.90 The dis-crepancy in rates made it unlikely that succinyl phosphate was an inter-mediate. The question has been settled by fractionation of the system intotwo enzymes, one of which catalyses the formation of phosphoryl-CoA fromATP and CoA, while the other transfers CoA from phosphoryl-CoA tos u ~ c i n a t e .~ ~ This reaction may involve a two-centre double displacement,in which a phosphate oxygen atom attacks the carbonyl-carbon atom ofsuccinyl-CoA nucleophilically, with concomitant electrophilic attack by thephosphorus atom on the sulphur atom, as implied by Hager.go A similarmechanism with acetoacetate replacing phosphate is implied by the briefreport that 180 is transferred to acetoacetate when [180]succinate and aceto-acetyl-CoA react in the presence of CoA-transferase.92The mechanism of the reaction catalysed by the glutamine synthetase-glutamotransferase complex is still obscure. The transfer of oxygen duringsynthesis of glutamine from the y-carboxyl group of glutamate tophosphate 83, 93 is compatible with the formation of either a-glutamylphosphate or a phosphorylated enzyme intermediate.The latter was atfirst thought to be involved, since the enzyme catalysed incorporation ofphosphate into ATP in the absence of amm~nia.~ However, with purermaterials it was found that ammonia was necessary for this reaction,94although it does not seem to be required for the exchange of ADP and ATPwith a less pure enzyme.95 On the other hand an attempt to implicatey-glutamyl phosphate has failedSg6 It also appears, from experiments with[14C]glutamate, that the glutamotransferase reaction does not proceed by86 M. B. Hoagland, P. C . Zamecnik, N. Sharon, F. Lipmann, M. P. Stulberg, and87 E. W. Davie, V. V. Koningsberger, and F. Lipmann, Arch.Biochcm. Biophys.,8 8 S. Kaufman, J . Biol. Chem., 1956, 216, 153.89 M. Cohn, in “ Phosphorus Metabolism,” Johns Hopkins Press, Baltimore, 1951,90 L. P. Hager, J . Amer. Chem. SOL, 1957, 79, 4864.91 R. A. Smith, I. F. Frank, and I. C. Gunsalus, Fed. Proc., 1957, 16, 251.92 P. D. Boyer, 0. J. Koeppe, W. W. Luchsinger, and A. B. Falcone, ibid., 1955,93 A. Kowalsky, C . Wyttenbach, L. Langer, and D. E. Koshland, jun., J . Bid.94 J. E. Varner and G. C. Webster, Plant Physiol., 1955, 30, 393.95 M. Staehelin and F. Leuthardt, Helv. Chim. Acta, 1955, 38, 184.98 L. Levintow and A. Meister, Fed. Proc., 1956, 15, 299.The reaction catalysed by succinic thiokinase is very different.P, D. Boyer, Biochim. Biophys. Acta, 1957, 26, 216.1956, 65, 21.Vol.I, p. 374.14, 185.Chenz., 1956, 219, 719GIBSON: ENZYME STUDIES WITH ISOTOPES. 316complete reversal of the synthetase rea~tion.~' Boyer and Fromin g8 haveattempted to account for these and other observations.It has been reported that the enzyme from plant tissues which synthesisesglutathione will catalyse an exchange between phosphate and ATP in thepresence only of y-glutamylcysteine ; 99 and similarly that the enzyme whichforms y-glutamylcysteine exchanges phosphate and ATP in the presenceonly of glutamate.100 However, partially purified enzyme from liver doesnot catalyse an exchange of phosphate and ATP at all,101,102 although itexchanges phosphate between ADP and ATP in the absence of othersub~trates,10~~1~~ and it incorporates glycine into glutathione if ATP orADP and phosphate or arsenate are present.lo2 Exchanges similar to theseare catalysed by the enzyme from plants which forms y-glutamylcysteine.lo0An anhydride of y-glutamylcysteine and phosphate has been postulated asan intermediate in glutathione synthesis.The formation of an anhydrideintermediate is indicated also in the synthesis of adenylosuccinate frominosinic acid, aspartate, and GTP. The enzyme responsible for this reactiondoes not catalyse exchange of phosphate between phosphate and GTP unlessinosinic acid and aspartate are present; and when it acts on [6-180]inosinicacid, 1 8 0 is found only in the phosphate formed, and not in adenylo-succinate.104 This was explained by anhydride formation betweenphosphate and inosinic acid or aspartate.A new biochemical mechanism is provided by the enzyme which formsS-methyladenosine from methionine and ATP,lo5 with release of phosphateand pyrophosphate.lo6 With 32P and 14C it has been shown that ATP,not ADP, is the substrate of the enzyme; and that phosphate arisesfrom the terminal phosphate group of ATP, and pyrophosphate fromthe other two groups.lo6 Also, one oxygen atom of phosphate is derivedfrom water of the medium, indicating cleavage of the terminal 0-P bond,but none of the oxygen of pyrophosphate comes from this source.106 Theresults have not yet been explained, but the reaction appears to be quiteunusual.Mutases and 1somerases.-When phosphoglucomutase was incubated withp2P]glucose l-phosphate the enzyme itself became radioactive,lo' and thisradioactivity could be transferred to a pool of glucose l-phosphate107 orglucose 6-phosphate.lo8 This was strong evidence for the formation of anenzyme-phosphate intermediate.However the discovery that glucose1 : 6-diphosphate stimulated the enzyme, and that it became labelledtogether with glucose 6-phosphate when the enzyme was incubated with97 L. Levintow, A. Meister, G. H. Hogeboom, and E. L. Kuff, J . Amer. Chenz. SOC.,9s P. D. Boyer and H. J. Fromin, Fed. R o c . , 1957, 16, 157.99 G. C. Webster and J. E. Varner, Arch. Biochem. Biophys., 1955, 55, 95.1956, 77, 5304.loo Idem, ibid., 1954, 52, 22.lol J. E. Snoke. S. Yanari, and K. Bloch, J . Biol. Chem., 1953, 201, 573.l o * J. E.Snoke and K. Bloch, ibid., 1955, 213, 825.103 J. E. Snoke, J . Amer. Chem. SOC., 1953, 75, 4872.104 I. Liebermann, J . Bid. Chem., 1956, 223, 327.106 G. L. Cantoni, ibid., 1953, 204, 403.106 G. L. Cantoni and J. Durell, ibid., 1957, 225, 1033.lo' V. Jagannathan and J. M. Luck, ibid., 1949, 179, 569.108 E. P. Kennedy and D. E. Koshland, jun., ibid., 1957, 228, 419316 BIOLOGICAL CHEMISTRY.p4C]glucose l-phosphate,log showed that the reaction was more complex.Najjar and Pullman 110 have now demonstrated that the mechanism of thereaction isGlucose I -phosphate + enzyme-phosphate glucose I : 6-diphosphate + enzymeGlucose I 6-diphosphate + enzyme glucose 6-phosphate + enzyme-phosphateThis is an interesting variant of Koshland's double displacementmechanism.A similar mechanism is involved in the phosphoglyceromutasereaction, as shown by the fact that 2 : 3-diphosphoglycerate is a cofactor u1and by the exchange of (non-isotopic) phosphate between diphosphoglycerateand phosphodihydroxybutyrate.l12During the conversion of fructose 6-phosphate into glucose 6-phosphatein [2H]water catalysed by phosphoglucose isomerase it was found that oneatom of deuterium becomes attached to Ct2) of glucose 6-phosphate; 113 thiswas taken to indicate that an intermediate ene-diol is formed. When[l-2H2]glucose 6-phosphate was acted on by this enzyme alone no isotopewas lost; but when the reaction was coupled with phosphomannose isomer-ase, there was loss of deuterium, indicating that these two enzymes showopposite specificity for the hydrogen atoms in position 1 of fructose 6-phosphate.Triose phosphate isomerase also catalyses the incorporation ofone atom of tritium from rH]water into the or-position of dihydroxyacetoneph0sphate.l l4It was at one time suggested that the epimerisation catalysed by galacto-waldenase was the result of a direct attack of water on the C o atom of thesubstrate.1b However when purification revealed that DPN+ is a cofactorof the enzyme,u5 it became clear that the reaction might proceed byoxidation and reduction. Recent results with isotopes support this view,since no 1 8 0 appears in the product when the reaction is carried out in[180]water,u63 117 and very little tritium when the medium is [3H]water.l17311*The fact that no tritium appears in UDP-glucose when the enzyme issupplemented with C3H]DPN or [3H]DPNH118 may mean that DPN isfirmly%ound to the enzyme.Carboxy1ases.-When phosphoenolpyruvate carboxylase 119 and carboxy-kinase 120 acted on their substrates in [12H]water, while the oxaloacetateformed was rapidly reduced with excess of DPNH and malic dehydrogenase,very little deuterium was found in the malate.It was concluded that ineach case oxaloacetate is produced in the keto- and not the enol form.During the decarboxylation in [2H]water of tyrosine, lysine, and109 E. W. Sutherland, T. 2. Posternak, and C. F. Cori, J . Biol. Chece., 1949,179, 501.110 V. A. Najjar and M. E. Pullman, Science, 1954, 119, 631.111 E. W. Sutherland, T. 2. Posternak, and C. F.Con, J . BZoZ. Chem., 1949,181,153.112 L. I. Pizer and C. E. Ballou, J . Amer. Chem. Soc., 1957, 79, 3612.113 Y. J. Topper, J . Biol. Chem., 1957, 225, 419.114 I. A. Rose and S. V. Rieder, Fed. Proc., 1956, 15, 337.116 E. S. Maxwell, J . Amer. Chem. Soc., 1956, 78, 1074.116 L. Anderson, A. M. Landel, and D. F. Diedrich, Biochim. Bioplzys. Ada, 1956,117 A. Kowalsky and D. E. Koshland, jun., ibid., p. 575.118 H. M. Kalckar and E. S . Maxwell, ibid., p. 588.119 T. T. Tchen, F. A. Loewus, and B. Vennesland, J . Bid. Chem., 1955, 213, 647.120 T. T. Tchen and B. Vennesland. ibid., p. 533.22, 573GIBSON : ENZYME STUDIES WITH ISOTOPES. 317glutamate by bacterial decarboxylases, one atom of deuterium is incorporatedin each case into the amine formed.121 These enzymes also catalyse directincorporation of deuterium from [2H]~ater into the same position of theamine.It has also been shown that when tyrosine, glutamate, and aspartateare decarboxylated in [l*O]water, there is no excess of l80 in the carbondioxide evolved.122 This rules out the possibility of acyl-enzyme formation ;and in fact all these results are consistent with the mechanism suggested onchemical grounds.121S 123An attempt has been made to apply isotopic methods to the reactioncatalysed by the carboxylation enzyme of spinach.lM When the enzymewas incubated with ribulose 1 : 5-diphosphate in [2H]water or rH]water, ineach case about half as much isotope was incorporated in the absence ofcarbon dioxide as in its presence.However, the extent of incorporationwas not sufficient in either case to support conclusively the formation of anene-diol intermediate; and the possibility of isotope effects on the rate madeit impossible to rule out such an intermediate.Other Enzymic Reactions.-Transaminase. The evidence from isotopeexperiments is in accord with the mechanism of transamination advanced bySnell.126 The rapid loss of deuterium from [~t-~H]glutamate was explainedin terms of formation of Schiff’s base with pyridoxal phosphate,126 and theincorporation of one deuterium atom from [2H]water into the a-position ofglutamate127*128 is consistent with this mechanism. The fact that pyr-idoxamine phosphate lowers the transfer of 15N from [15N]aspartate tog l ~ t a r n a t e , ~ ~ ~ the incorporation of 15N from [15N]pyridoxamine phosphateinto glutamate catalysed by a crude preparati~n,l~~ and the rapid transferof 14C from [14C]glutamate to a-oxoglutarate catalysed by purified trans-arnina~e,l~~ all support the postulated role of pyridoxal and pyridoxaminephosphate.Studies with 2H and 15N have also provided evidence for aternary enzyme-substrate complex,128 with the same binding sites forcorresponding oc-amino- and a-o~o-acids.~~~AZdoZase. Aldolase catalyses the incorporation of tritium from rH]waterinto the a-position of dihydroxyacetone 133 Further, thetritium introduced by this enzyme is not removed by triose phosphatei~omerase,l~~~ 133 indicating opposite specificities for the a-hydrogen atoms.Glyoxalase.Racker’s suggestion that an ene-diol intermediate isformed during the action of glyoxalase I on methylglyoxal was ruled out bylZ1 S. Mandeles, R. Koppelman, and M. E. Hanke, J . Biol Chem., 1954, 209, 327.lZ2 S. Rothberg and D. Steinberg, J . Amer. Chem. SOC., 1957, 79, 3274.lZ3 D. E. Metzler, M. Ikawa, and E. E. Snell, ibid., 1954, 76, 648.lZ4 J. Hurwitz, W. B. Jakoby, and B. L. Horecker, Biochinz. Biophys. Ada, 1956,125 E. E. Snell, J . Biol. Chem., 1944, 154, 313.lZ6 A. S. Konikova, N. N. Dobbert, and A. E. Braunstein, Natuw, 1947, 159, 67.12’ M. A. Hilton, F. W. Barnes, jun., S. S . Henry, and T. Enns, J . Biol. Chem.,12* M. A. Hilton, F. W. Barnes, jun., and T. Enns, ibid., 1956, 219, 833.12* S. W. Tanenbaum, ibid., 1956, 218, 733.130 W.T. Jenkins and I. W. Sizer, J . Amer. Chem. SOL, 1951, 79, 2655.131 A. Nisonoff, F. W. Barnes, jun., and T. Enns, J . Biol. Chewa., 1953, 204, 967.132 I. A. Rose and S. V. Rieder, J . Amer. Chem. SOC., 1955, 77, 5764.133 B. BIoom and Y . J. Topper, Science, 1956, 124, 982.la4 E. Racker, J . Biol. Chem., 1951, 190, 686.22, 194.1954, 209, 743318 BIOLOGICAL CHEMISTRY.the observation that little tritium is incorporated when the reaction is in[3H]water.135 A hydride shift has been suggested.135Perhaps the first exchange to be discovered was thatbetween [2H] hydrogen and water, catalysed by hydrogenase.136 It waslater found 13' that the first product was lH2H, and from a study of the ex-change reaction and the conversion of ortho- into para-hydrogen catalysed bythis enzyme it has been suggested that an intermediate of the typeenzyme-H- is formed.13sIn recent years an attack has been made onthis problem in the case of certain hydrolytic enzymes which are inhibitedby DFP.It is well established that DFP inhibits by combining directlywith a group at or near the active centre,139 and use has been made of thisfact to label the enzyme with 32P and then to degrade the labelled proteinand examine the peptide products. Work on these lines has been reviewedalready; 139s140 it appears that trypsin, chymotrypsin, acetylcholinesterase,and an esterase all have the same or a very similar amino-acid sequencecentring round the serine residue which actually combines with the phosphateof DFP.139a141 The technique has now been extended to some enzymeswhich can be labelled directly with 32P during the course of the reactionswhich they catalyse, and it has been possible to isolate radioactive serinephosphate from hydrolysates of [32P]-labelled phosphoglucomutase,los~ 142s143hexokinase,la and muscle pho~phory1ase.l~~ There is good evidence to showthat the phosphate of phosphoglucomutase which is enzymically active isactually attached to serine and does not migrate there as a result of experi-mental manipulation ; 1083143 and this agrees with the fact that the free energyof hydrolysis of the active enzyme-phosphate bond is about -3.9 kcal.,i.e. the bond is not energy-ri~h.~~~ In this one case the identification of theactive centre has been carried further by the isolation of several peptidescontaining phosphoserine, whose amino-acid composition was consistent withthe sequence A~pSerGlyGluAlaVal,~~~ a sequence which has also been foundin chym~trypsin.~~~Conclusion.-The use of isotopes has revealed a number of examples ofsteric specificity in enzymic reactions.Many of these can be explained byapplying the " three-point attachment " hypothesis 147 to the part of thesubstrate molecule which is actually involved in the reaction; if this partof the molecule possesses a one-fold axis of symmetry, the enzyme may beHydrogenase.Structure of active centres.135 I. A. Rose, Biochim. Biophys. Ada, 1957, 25, 214.136 A. Farkas, L. Farkas, and J. Yudkin, Proc. Roy. SOL., 1934, B , 115, 378.137 H.D. Hoberman and D. Rittenberg, J . B i d . Chem., 1943, 147, 211.138 A. I. Krasna and D. Rittenberg, J . Amer. Chem. Soc., 1954, 76, 3015.139 W. N. Aldridge, Ann. Reports, 1956, 53, 294.140 B. S. Hartley, ibid., 1954, 51, 303.141 J. A. Cohen, R. A. Oosterbaan, and M. G. P. J. Warringa, Discuss. Favaday142 D. E. Koshland, jun., and M. J. Erwin, J . Amer. Chem. SOL., 1957, 79, 2657.145 L. Anderson and G. R. Jolles, Arch. Biochem. Biophys., 1957, 70, 131.144 G. Agren and L. Engstrom, Acta Chem. Scand., 1956, 10, 489.145 L. Engstrom and G. Agren, ibid., p. 877.146 J. B. Sidbury, jun., and V. A. Najjar, J . B i d . Chem., 1957, 227, 617.147 A. G. Ogston, Nature, 1948, 162, 963; D. W. Racusen and S. Aronoff, Arch.SOC., 1956, 20, 114.Biochem.Biophys., 1951, 34, 219WHELAN : NEURAMINIC ACID. 319expected to attack it asymmetrically. Work with isotopes also offers strongsupport for the view that many enzymic reactions proceed by single ordouble displacement substitutions, with formation in some cases of anenzyme-substrate intermediate. It is evident that similar overall reactionsare brought about by similar mechanisms; and as there are not many typesof overall reaction, so there may be only a few types of mechanism. It isprobably true that there is no basic difference between enzymic and non-enzymic catalysis in the nature of the reaction catalysed,l or even the methodof catalysis,2 but that the difference lies in the extreme chemical and stericspecificity found in enzymic reactions.K. D. G.3. NEURAMINIC ACID.NEURAMINIC ACID (I) is now recognized to be of wide occurrence as part ofthe carbohydrate-protein complexes of animals. For example, orosomucoid,an acidic glycoprotein, constitutes 10% of human-serum glycoprotein, andcontains 12% of an N-acetylneuraminic acid.l The free amino-compound(I) has not yet been isolated, the amino-group always being substitutedwith the acetyl or glycolloyl radical. The only report of the occurrence ofneuraminic acid in a non-mammalian source is a very recent one describingan acidic polysaccharide, colominic acid, elaborated by Escherichia coliK235. This polysaccharide seems to consist solely of repeating units ofN-acetylneuraminic acid.la Neuraminic acid is properly regarded as acarbohydrate, resulting from an aldol condensation betweenpyruvic acid and D-glucosamine,2 and the N-acetyl derivativehas been synthesized by condensing oxaloacetic acid andN-acetyl-D-glucosamine in alkali, followed by decarboxyl- 1 H O - F H ation (Fig.1). The N-acetyl derivative reduces Fehling’sH-c-NH2 solution, but not after treatment with sodium borohydride,C-H and forms a methyl glycoside with methanolic hydrogen IH-c-OH chloride, losing the acetyl group in the process. It has theIH-C-OH acid lability of a 2-deoxy-sugar. It is intended here to reviewI(1) CH,.OH the structure, properties, and occurrence of neuraminic acidbut not its possible physiological r81e, except for its functionas the blood-cell receptor for the influenza virus, because this aspect isintimately bound up with the history of the structural investigations. Arecent CIBA Foundation symposium deals with all aspects of neuraminicacid. Other relevant reviews are those by K ~ h n , ~ Heyns,6 and Klemer.71 R.J. Winzler, “ Methods of Biochemical Analysis,” Interscience Publishers Inc.,New York, 1955, Vol. 11, p. 279.16 G. T. Barry, Science, 1957, 126, 1230; G. T. Barry and W. F. Gaebel, Nature,1957, 179, 206.A. Gottschalk, Nature, 1955, 176, 881.3 J . W. Cornforth, M. E. Daines, and A. Gottschalk, Proc. Chem. SOL, 1957, 25;J . W. Cornforth, M. E. Firth, and A. Gqttschalk, Biochem. J., 1958, 88, 57.4 CIBA Foundation Symposium: The Chemistry and Biology of Mucopoly-saccharides,” J . & A. Churchill Ltd., London, 1958.6 R.Kuhn, Angew. Chem., 1957, 69, 23.6 K. Heyns, Strirke, 1967, 8, 85.7 A. Klemer, Chem. Tech. (Berlin), 1967, 9, 584320 BIOLOGICAL CHEMISTRY.The most complete account of the properties of neuraminic acid derivativesis that by Blix et aZ.8Nomenclature. Many different names have been applied to substancesnow recognized as being derivatives of the parent neuraminic acid.8u Onlyrecently has an agreed system of nomenclature been devised. Blix,Gottschalk, and Klenk “ propose to call the basic, unsubstituted compoundneuraminic acid (I), and sialic acid is suggested as a group name for theacylated neuraminic acids (for example, N-acetylneuraminic acid, N-gly-collylneuraminic acid, diacetylneuraminic acid). For the enzyme whichsplits the glycosidic linkage-joining the terminal sialic acid to the residualTABLE 1.Synonyms of neuraminic acid and its derivatives.MolecularformulaNeuraminic acid C9H1708NMethyl neuraminosidic acid CIOH 1 !Pa5- N-Acetylneuraminic acid CllHl,O,NMethyl 5-N-acetylneuraminidate CIZH210,N6-N-Glycolloylneuraminic acid ClIHl9OlON5-N-Acetyl-7-O-acetylneuraminic acid Cl,H,,Ol0N5-N-Acetyl-?-O-acetylneuraminic acid Cl,H,,OIoNSynonymsPrehemataminic acid loMethoxyneuraminic acid 11. 1sHemataminic acid 10O-sialic acid (ovine) 8Gynaminic acid l3. l4Lactaminic acid 16- 1 7Serolactaminic acidMethoxylactaminic acid 15* 16* l 7B-sialic acid (bovine) 8E-sialic acid (equine) 8P-sialic acid (porcine) 8oligo- or poly-saccharide the names neuramidase and sialidase may be usedsynonymously.” Table 1 correlates names applied according to thissystem with names used in the past.A fully descriptive name for neur-aminic acid itself is 5-amino-3 : 5-dideoxy-~-erythro-~-gu~Zo-nonulosonic acid.Structure of neuraminic acid. Blix l9 isolated the first crystallinederivative of neuraminic acid in 1936, although reports of such compoundsgo back to 1900.20 Blix heated an aqueous solution of bovine submaxillarygland mucoprotein (BSM), causing a crystalline substance (B-sialic acid;0.1% yield) to be split off. The process is one of autohydrolysis. B-sialicacid has pKu 2.60.8 Like BSM itself the substance gave huminous materialwhen heated in acid or alkali. Elementary analysis suggested the formula“ C,,H,,O,,N ” and the molecule had one titratable carboxyl and two acetylG:Blix, E.Lindberg, L. Odin, and I. Werner, Acta SOC. Med. Uppsaliensis, 1956,81, 1.8a I. Werner and G. Blix, Bull. Soc. chim. belges, 1956, 65, 202. * F. G. Blix, A. Gottschalk, and E. Klenk, Nature, 1957, 179, 1088.10 T. Yamakawa and S. Suzuki, J . Biochem. (Japan), 1951, 38, 199; 1952, 39, 175.100 E. Klenk and H. Wolter, 2. physiol. Chem., 1952, 291, 259.11 E. Klenk, ibid., 1941, 287, 128; 268, 50.12 Idem, ibid., 1942, 273, 76.la J . R. E. Hoover, G. A. Braun, and P. Gyorgy, Arch. Biochem. Biophys., 1953, 47,l4 F. Zilliken and M. C. Glick, Natuvwiss., 1956, 43, 536.l 5 R. Kuhn and R. Brossmer. Ber., 1954, 87, 123.l6 Idem, Angew. Chem., 1956, 88, 211; Ber., 1956, 89, 2013.1’ Idem, Ber., 1956, 89, 2471.18 T.Yamakawa and S. Suzuki, J . Biochem. (Japan), 1955, 42, 727.20 E. Leathe, Arch. Ex$. Path. P h u r ~ . , 1900, 43, 245.216; I;. Zilliken, G. A. Braun, and P. Gyorgy, ibid., 1955, 54, 564.G. Blix, 2. physiol. Chem., 1936, 240, 43; Scand. Arch. Physiol., 1938, 80, 46WHELAN NEURAMINIC ACID. 32 1groups. It gave a red-purple colour in a “ direct ” reaction * with acidified9-dimethylaminobenzaldehyde (Ehrlich reagent) and a red-violet colourwith Bial’s orcinol reagent. These two colour tests and also modificationsof the tryptophan-perchloric acid and diphenylamine tests for deoxy-pentoses form the present methods of recognizing and estimating neuraminicacid.1924125 The standard of reference is usually Blix’s B-sialic acid orN-acetylneuraminic acid.Blixl9 also noted that brain contained a sub-stance with the colour reactions of B-sialic acid and in 1941 Klenk isolateda crystalline product by treatment of brain lipid with hot methanolichydrogen chloride. This was termed neuraminic acid, was direct-Ehrlichpositive and non-reducing. Two molecular formulae were considered,C11H210,N and CloH1,O,N. The former was adopted, but the latter hasproved to be correct (see below). Later, realizing that the extractionprocedure introduced a methoxyl group (see below), Klenk l2 gave the nameneuraminic acid to the methoxy-free compound, which constituted 21% ofthe lipid. Since that time methoxyneuraminic acid and other crystallinederivatives (Table 1) have been isolated from a wide variety of animalsources (see below).Speculation on the structure of neuraminic acid has ranged widelyalthough most formulations have recognized the likely relation of the acidto an amino-sugar.Blix19 thought a t first that his B-sialic acid (Table 1)was a combination of N-acetylhexosamine and a polyhydroxy-acid, and atleast 10 other structures have been proposed, 6 of these by Gottschalk,who is credited with the correct formulation of the skeleton of neuraminicacid2 and who, with Cornforth and Firth,3 has synthesized the N-acetylderivative. The structural investigations have been handicapped for anumber of reasons, inter al. : (1) Reducing derivatives of neuraminic acidare extremely labile towards acid and alkali, although it was assumed a tone time that alkali had no effect, and therefore that N-acylhexosaminecould be excluded as a component of the compound.26 (2) The variousderivatives are usually crystallized from methanol.It is now realized thatthis may cause the formation of methyl esters.8s16p17s 279 28s 29 (3) Elementaryanalyses have been used to support two molecular formulae for neuraminicacid, CloHl,0,N30 and C,H1,0,N.8 That the latter is correct has beenconclusively demonstrated by titration of the carboxyl group 8s 1 6 s 1 7 7 2921 A. Gottschallr, Biochem. J., 1955, 61, 298.22 W. T. J. Morgan and L. A. Elson, ibid., 1934, 28, 988.23 L. A. Elson and W. T. J. Morgan, ibid., 1933, 27, 1824.24 I. Werner and L. Odin, Acla. SOC. M e d .Uppsaliensis, 1952, 57, 230.25 L. Svennerholm, Arhiv Kemi, 1957, 10, 577.26 A. Gottschalk, Nature, 1951, 167, 845.27 R. Heimer and K. Meyer, Proc. Nut. Acad. Sci. U.S.A., 1956, 42, 728.28 R. Heimer, Diss. Abs., 1957, 17, 1656.2B L. Svennerholm, Acta SOC. M e d . Uppsaliensis, 1956, 61, 75.30 E. Klenk, H. Faillard, F. Weygand, and H. H. Schone, 2. physiol. Chem., 1956,304, 36.* A direct ’’ reaction means that colour formation takes place on heating with theEhrlich reagent. Some substances (e.g. pyrrole-2-carboxylic acid 21) react in the cold.N-Acetamido-sugars give a similar colour only after pretreatment with alkali (Morgan-Elson reaction 22) and free amino-sugars after pretreatment with alkaline acetylacetone(Elson-Morgan reaction 2 z ) .The occurrence of neuraminic acid along with hexosaminemay influence estimates of the latter made with the Ehrlich reagent.24REP.--1’OL. LIV 1322 BIOLOGICAL CHEMISTRY.although complications arise here if methyl ester is present [see (2)]. (4)The O-acetyl group in B-sialic acid is extremely labile to acid and alkaliand is detached during alkali titration of the carboxyl g r ~ u p . ~ s ~ ~ * ~ ~ It isthe failure to recognize this that may have been responsible for the doubtscast on the existence of the diacetyl c0mpound.~1 Even so, crystallinepreparations of B-sialic acid yielded four spots in paper chromatographyand may have contained only two-thirds of the main component, theimpurities being " closely related compounds." (5) The sialic acids areoxidized by alkaline hypoiodite, although less rapidly than aldoses.83 8aThis gave the impression that they contain an aldehydicPerhaps the first significant clue to the structure of neuraminic acid wasHiyama's (1949) 32 isolation of crystalline pyrrole-2-carboxylic acid fromBSM and from B-sialic acid after refluxing them with alkali.This establishedthe relative positions in the neuraminic acid molecule of the amino- andthe carboxyl group, these being assumed to be respectively the sources of thehetero-nitrogen atom and the carboxyl group in the pyrrole compound.Hiyama adopted what has proved to be the correct molecular formula ofB-sialic acid (Table 1) and suggested that the acid was a pyrrolidinederivative, converted by alkali into pyrrole-2-carboxylic acid and erythrose,the latter being responsible for the copper-reducing power.In 1951Yamakawa and Suzuki lo isolated " hemataminic acid '' by applying Klenk'sisolation procedure to horse-blood stroma lipid and drew attention toits close similarity to Klenk's methoxyneuraminic acid. They used thecorrect molecular formula, C,Hl7O,N, for the methoxy-free compound,prehemataminic acid, and suggested that it might arise by " condensationof hexosamine and glyceric acid, following the liberation of one mole ofwater." The proposed structure was correct except for the dispositionof the deoxy- and carboxyl groupings. Meanwhile, Gottschalk 26 had beeninvestigating the " split product " released by influenza virus from BSMand human urinary mucoprotein (see below).The connection of thissubstance with the sialic acids was suggested by Odin33 and by Klenk,and Lauenstein 33a and Gottschalk confirmed the formation of pyrrole-2-carboxylic acid by alkali but suggested that this was itself an integral partof the split product. However, this idea was revised when BSM was foundnot to show the ultraviolet adsorption of the pyrrole acid and two furtherformulae 359 36 were proposed, these containing pyrroline nuclei. Followingthe demonstration by Blix et aZ.37 that B-sialic acid has the molecularformula C,,H,,O,,N, an N-acetyl group, and O-acetyl group, a primaryhydroxy-, an a-hydroxy-, and a total of five hydroxy-groups," Gottschalkproposed a formula for B-sialic acid which has proved to be correct, except31 E.Klenk and G. Uhlenbruck, 2. physiol. Chern., 305, 224.32 N. Hiyama, Tohoku J . Exp. Med., 1949, 51, 317.33 L. Odin, Nature, 1952, 170, 663.320 E. Klenk and K. Lauenstein, 2. physiol. Chem., 1952, 291, 147.3p A. Gottschalk, Nature, 1953, 172, 808.35 Idem, ibid., 1054, 174, 652.36 Idem, Yale J . Biol. and Med., 1954, 26, 352.37 G. Blix, E. Lindberg, I,. Odin, and I. Werner, Nature, 1955, 175, 340.* Although B-sialic acid very probably contains a total of five hydroxyl groups thestatement was later withdrawn.WHELAN : NEURAMINTC ACID. 323for the position of the O-acetyl group, suggested to be at C(Q), but shown byBlix et al. to be at C(7). Most of the structural work on which the formul-ation rests came later.The following are the significant steps: (i) Periodateoxidation studies on 0-, B-, and P-sialic acids and on methyl neuraminosidicacid (Table 1) agreed with the formula and showed that neuraminic acidexists in the pyranose form (I) (see also refs. 10, 18, 30, and 38). (ii)N-Acetylneuraminic acid (O-sialic acid) was split into N-acetyl-D-glucos-amine, carbon dioxide, and an unidentified C, compound when heated withnickelous acetate in pyridine.17 This established the configuration atC(5), Alkaline degradation of O-sialic acid, under milderconditions than produce pyrrole-2-carboxylic acid, gave N-acetyl-D-glucos-amine and pyruvic acid.14 Methyl O-sialate was split into the same twoproducts by an enzyme preparation from Vibrio cholera (see below) .279 28When heated in alkali these two compounds gave 20% of the theoreticalyield of pyrrole-2-carboxylic acid.39 (iii) N-Acetylneuraminic acid wassynthesized by condensing oxaloacetic acid and N-acetyl-D-glucosamineat pH ll.3 Theonly isomer isolated had the specific optical rotation and infrared spectrumof the natural O-sialic acid.on the basis of the apparent failure of the acid to form a lactone but Kuhnand Brossmer 40 have shown that a mercaptal lactone can be formed, thenegative rotation of which indicates an L-glycero-configuration at C(s) (I).The remaining structural uncertainty, the configuration at C(,), was solvedat the same time by observing the direction of mutarotation of N-acetyl-neuraminic acid in dimethyl sulphoxide.Mutarotation had not beenobserved in other solvents. The p-configuration was assigned to thecrystalline compound. The foregoing reactions are summarized in Fig. 1."Some of the derivativesof neuraminic acid which have been isolated from natural sources are shownin Table 1. Methyl esters have also been characterized (Fig. 2). Althoughthe amino-group always seems to be acylated in vivo the lability of theO-acetyl groups renders uncertain the degree of acylation of neuraminicC(7), and Co).In this process an asymmetric atom is created a t C(4).A D-glycero-configuration at C(4) was suggestedPreparation and sources of the sialic acids.38 F. Weygand and H. Rinno, 2. physiol. Chem., 1957, 306, 177.3g A. Gottschalk, Arch. Biochem. Biophys., 1957, 69, 37.39,3 Idem, ref.4, p. 289.40 R. Kuhn and R. Brossmer, Angew. Chem., 1957, 69, 534.* Since this Report was prepared a preliminary communication has appeared whichsuggests that the amino-sugar component of neuraminic acid is not D-glucosamine butD-mannosamine (D. G. Comb and S. Roseman, J . Amer. Chem. Soc., 1958, 80, 497).An enzyme preparation from Clostridium perfringens (cf. ref. 57) cleaved N-acetyl-neuraminic acid from human plasma into pyruvic acid and N-acetyl-D-mannosamine(identified as the crystalline hydrochloride). The same enzyme preparation re-synthesised N-acetylneuraminic acid from these two products and established equi-librium between 1 part of N-acetylneuraminic acid and 9 parts of pyruvic acid plusacetylmannosamine. N-Acetyl-D-glucosamine or N-acetyl-D-galactosamine could notbe substituted for N-acetyl-D-mannosamine in this synthesis.The same enzymesystem also split N-acetylneuraminic acid from sheep submaxillary mucin and E . coli a tthe same rate as the human-plasma acid (rate = 100). N-Glycolloylneuraminic acidfrom pig submaxillary mucin (65), ON-diacetylneuraminic acid from BSM (14), but notmethoxyneuraminic acid, were also split. Comb and Roseman conclude that " in viewof the specificity of the enzyme it appears likely that sheep-submaxillary mucin andE. coli neuraminic acids are identical with human-plasma neuraminic acid.324 BIOLOGICAL CHEMISTRY.FIG. 1. Synthesis and degvadlation of N-acetytnewcsminic mid.N- AcetyI-D-glucosam-ne +oxaloacetic acid(2) (3)N-Acetyl-D-glucos- N-Acetylneuraminic ___) Methyl neuraminosidicamine + CO, + C,N-Acetyl-D-glucos- -W PyrroIe-%carboxylic 5-N-Acetyl-7-O-acetyl-+ amine + pyruvic acid acid neurarninic acidtetrose sugar (?)(1) At pH 11 at room temperature.(3) Meth-anolic hydrogen chloride a t 105". (4) y. cholera enzyme or 0-1N-sodium hydroxide a t90". (5) 40% Sodium hydroxide a t 100 . (6) 0-OlN-Sulphuric acid at 4". (7) Refluxedwith barium hydroxide solution; pH 11.t A 4-hydroxypyrroline derivative has been suggested as an intermediate in thesereactions, the position of the double bond being given variously as a t Ctl)-C(2),3QP(2) (CH,.CO,),Ni-pyridine a t 100".C(Z)--C(Z)> 21 and c(s)-c(4).36acid in vivo for the conditions of isolation may effect a dea~etylation.40~For example, both N-acetyheuraminic acid and diacetylneuraminic acid(B-sialic acid) have been obtained from BSM.89 46 However, the conditionsof autohydrolysis whereby B-sialic acid may be obtained from BSM giveN-acetylneuraminic acid when applied to ovarian and auto-hydrolysis of O-acetyl-lactaminic acid-lactose (Tables 1 and 2) yieldsN-acetylneuraminic acid, lactose, and acetic acid.16 (The position of theO-acetyl group is not known.) With some mucoids very little product isobtained by autohydrolysis and hot dilute acid must be used to release theneuraminic acid, which then appears as the N-acetyl compound.41 Themethyl ester and glycosidic groups found in some derivatives (Fig.2) areintroduced during the isolation procedure and are not of natural origin.The ester group is introduced by autocatalysis (see above) and the methylglycosidic group enters the molecule when Klenk's isolation procedure l1(methanolic hydrogen chloride at 105") is applied to the native material or toN-acetylneuraminic acid.By using [14C]methanol in this reaction Klenk 30has shown that the resulting methyl neuraminosidic acid is radioactive.It is of interest that the N-glycolloyl derivative occurs in erythrocyte stromabut in the blood-serum proteins it is the N-acetyl derivative which is found.In the horse, N-acetylneuraminic acid is found in the serum mucoprotein,l8S 52N-glycolloylneuraminic acid in the erythrocyte ~ t r o r n a , ~ ~ ~ s2a$ 63 and adi-0N-acetylneuraminic acid in the submaxillary gland mucoprotein.Theposition of the O-acetyl group is not known, except that it is not at C(,),as in B-sialic acid (Tables 1 and 2, Fig. 2). Table 2 lists some of the animal40a A. Gottschalk, Yale J . Biol. and Med., 1956, 28, 526.4l L. Odin, Acta Chem. Scand., 1955, 9, 862.4 2 Idem, ibid., p. 714WHELAN NEURAMINIC ACID. 325TABLE 2. Sources of neuraminic acid."Methyl neuraminosidic acid :Human-brain lipid,". 1 9 bovine- 49 and horse-erythrocyte lo* lOa stroma, f e t ~ i n , ~ ~brain ganglioside,d5 human-milk mucopolysaccharides,13 BSM,8* 31. 33a* 46 human-serummu~oprotein,~' cow colostrum,31 horse and pig submaxillary gland m~coprotein,~~human urinary mucoprotein,3- whole rat tissue ("C-derivative) .47*5-N- Acetylneuraminic acid :BSM,27. 28.4% 4 % 4% 49~3 lactiminic acid-lactose,15* 1 7 human cervical mucus,5opig seminal gel,5o ovomucin,60 human-serum protein,29* 41* 62e 539 54 rneconi~m,~~ oroso-m u ~ o i d , ~ ~ ~ 55, 5% 57 human ovarian cysts,42 dialysable *9 and non-dialysable la fractionsof human milk, human urinary muc~protein,~~~ 49* 58 horse-serum mucoprotein,l8v 62human-erythrocyte stroma,Q 60 horse haematoside,62 human liver, 61 human-brainganglioside,30. 51, 62 lipid-free human-brain tissue,30 colominic acid (E. coli) .lo5-N-Acetyl-7-0-acetylneuraminic acid :5-N-Acetyl-?-O-acetylneuraminic acid :5-N-Glycolloylneuraminic acid :stroma,42"s 63 horse-stroma ganglioside.62a. 63Detection of neuraminic acid by colorimetric test:Neuramin-lactose,64* 85, 8 5 0 epithelial mucins,gs human-blood group substance^,^'dialysable brain lipid fraction,ss group A, B, and 0 substances of human urine,59human-brain ganglioside, 6 9 human cerebrospinal fluid, 'O human and cow milk, human,sheep, cow, pig, and goat colostrum.l8* In most cases the derivatives were isolated crystalline and in high yield, based onthe estimated content of sialic acid in the animal part.43 E.Klenk and W. Stoffel, 2. physiol. Ckem., 1956, 303, 78.44 Idem, ibid., 1955, 302, 286.46 E. Klenk, ibid., 1951, 288, 216.46 E. Klenk and H. Faillard, ibid., 1954, 298, 230.47 P. Bohm and L. Baumeister, ibid., 1955, 300, 153.470 K. Lauenstein and K. I. Altman, Nature, 1956, 178, 917.H. Faillard, 2. physiol. Chem., 1956, 305, 145.49 Idem, ibid., 1957, 307, 62; 308, 187.49a Y.Saito, Nature, 1956, 178, 995.6 o L. Odin, Acta Chem. Scand., 1955, 9, 1235.51 L. Svennerholm, i b i d , p. 1033.52 T. Yamakawa, J . Biochem. (Japan), 1956, 43, 867.53 P. Bohm, J. Ross, and L. Baumeister, 2. physiol. Chem., 1957, 308, 181.54 Idem, ibid., 1957, 307, 284.5 5 I. Yamashina, Acta Chem. Scand., 1956, 10, 1666.56 J. L. Oncley, E. H. Eyler, and K. Schmid, XI1 Conference on Blood Cells andPlasma Proteins, New York State Department of Health, Division of Laboratories andResearch, 1957, p. 15.5 7 E. A. Popenoe and R. M. Drew, J . Bid. Chem., 1957, 228, 673.5 8 E. Klenk, H. Faillard, and H. Lempfrid, 2. physiol. Chem., 1955, 301, 235.6 o E. Klenk and H. Lempfrid, 2. physiol. Chem., 1957, 307, 275.62 G.Blix and L. Odin. Acta Chem. Scarzd., 1955, 9, 1541.63 E. Klenk, ref. 4, p. 300.64 R. E. Trucco and E. Caputto, J . Bid. Chem., 1954, 206, 901.65 R. Heyworth and J. S. D. Bacon, Biochenz. J., 1957, 66, 41; M. Shilo, ibid., p.48.65a A. Gottschalk, Biochim. Biophys. Acta, 1967, 23, 645.6 6 L. Werner, Acta SOC. Med. Uppsaliensis, 1953, 58, 1.6 7 R. A. Gibbons, W. T. J. Morgan, and M. Gibbons, Biochem. J., 1955, 00, 428.6 8 A. Rosenberg, C . Howe, and E. Chargaff, Nature, 1956, 177, 234.6 9 S. Bogoch, J . Amer. Chem. Soc., 1957, 79, 3286; Nature, 1957,180, 198; Biochenz.'O L. L. Uzman and M. K. Rumley, Proc. SOC. Exp. Bid. Med., 1956, 93, 497.BSM aHorse submaxillary gland mucoproteinPig submaxillary gland mucoprotein,89 mu horse-, 52 pig- and cow-erythrocyteH.Masamune, S. Hakamori, 0. Masamune, and S. Takase, Tohoku J . Exp. Med.,A. Martinsson, A. Raal, and L. Svennerholm, Biochim. Biophys. Ada, 1957, 23,652.1956, 64, 67.E. Klenk and G. Uhlenbruck, Z . physiol. Chem., 1957, 307, 266.J., 1958, 68, 319326 BIOLOGICAL CHEMISTRY.sources from which neuraminic acid derivatives have been obtained, or inwhich colour reactions suggest the presence of the acid. A " sialic acid I1 "which does not seem to be identical with any of those listed in Tables 1 and2 has been found in orosomu~oid.~~ Also, a sialic acid released enzymicallyfrom a lactose-sialic acid compound has not yet been cla~sified,~~ beingdifferent from N-acetyl- and methoxy-neuraminic acid (Table 3).It now seems fairly certain that the crystalline direct-Ehrlich positivesubstances isolated from various animal sources and which at first werethought to be different from already known derivatives of neuraminic acid,e g ., hemataminic acid lo* loa (=methyl neuraminosidic acid, Table 1), arebased on the same parent neuraminic acid. Fig. 2 depicts the inter-FIG. 2. Inter-relations of sialic acids from submaxillary-gland mucins (cf. Table 1).Methyl neuraminosidic acidHorse 1- mucin / Bovine t mucin Sheep mucin v f u c i nP-sialic acid 1 i E-sialic acid B-sialic acid O-sialic acidMethyl I iP-sialateP MethylO-sialaterelations of the submaxillary gland sialic acids as established by Blix et aZ.*and Klenk and U h l e n b r ~ c k . ~ ~ These reactions indicate that the neuraminicacid structure is common to all the compounds.It will be of interest todiscover whether D-glucosamine is the only amino-sugar to be found incorpor-ated into the sialic acids.71In 1941 Hirst 72 and McClellandand Hare 73 independently observed that influenza virus added to chickred-blood cells caused haemagglutination (clumping). Hirst 74 later showedthat at 37" the virus slowly detached itself from the cells. The elutedvirus could cause agglutination of fresh cells but the treated cells would nolonger agglutinate. These and other observations led Hirst to liken theagglutination process to an enzyme-substrate complex formation. Thered cells were thought to contain a receptor (substrate) which combinedwith the virus (enzyme).The process of elution of the virus was caused bythe removal of the receptor from the blood cell. This idea has proved tobe correct. Enzymes were discovered which detached the red-cell receptor,notably that from Vibrio cholera, termed the receptor-destroying enzyme(RDE).75 In 1947 Francis 76 discovered that all normal sera contain asubstance capable of inhibiting virus agglutination. Many mucoproteinsThe blood-cell receptor for inJEuenza virus.71 W. T. J. Morgan, ref. 4, p. 305.72 G. I(. Hirst, Science, 1941, 94, 22.73 L. McClennan and R. Hare, Canad. J . Pub. Health, 1941, 32, 530.74 G. K. Hirst, J . Exp. Med., 1942, 75, 49; 76, 195.5 5 F. M. Burnett, Ann. Rev. Microbiol., 1952, 6, 220.7 8 T. Francis, J . Exp. Med., 1947, 85, 1WHELAN : NEURAMINIC ACID.327were found to be inhibitory, for example, BSM and human urinary muco-protein.75 Influenza virus or RDE releases a dialysable compound of lowmolecular weight (" split product ") from these substances and they thenlose their inhibitory activity.75 It was natural to conclude that these inhibi-tors contained the blood-cell receptor substance and that this was the splitproduct. The similarity of the colour reactions of the split product to thoseof the sialic acids was noted by Odin 33 and by Klenk and Lauenstein 33a(see above). Crystalline N-acetylneuraminic acid was then isolated byTABLE 3. Enzymic release of sialic acids."Substrate Enzyme Product i tBSM RDE 27, 28, 48, 49Human-serum muco- Influenza virus, A-toxin ofprotein Clostridium welchii, 53Orosomucin Pneumococcal enzyme, 56RDE 54C1ostridium Perfringens N-Acetylneuraminic acidUnidentified product (seeDi-ON-acetyl- or N-enzyme 5 7Human-erythrocyte RDE 6oHuman urinary muco- Influenza RDENeuramin-lactose Influenza virus, RDE 65s JNeuramin-lactose (?) Gram-negative bacteria,O- Acetyl-lactaminic acid- Influenza virus RDE l6Pig submaxillary gland RDE 62cr 63 N-Glycollo ylneuraminicstromaproteinPseudomonas spp.Lacto- text)bacillus bijidus 6 5lactose acetyl-neuraminic acidmucoprotein acid* Trypsin also destroys the agglutination-inhibiting activity of BSM 27 but does notattack the virus receptor of human-erythrocyte stroma 7 7 and attacks orosomucoid onlyafter removal of sialic t This is said to contain an 0- and an N-acetyl gr0~p,65= but Kuhn and Brossmer l6point out that the acetyl content was not measured 1 3 ~ and that the conditions of isolationwould probably have detached an O-acetyl group.Klenk et al.58 from inhibitory human urinary mucoprotein treated withinfluenza virus, and later from blood cells themselves (human-erythrocytestroma) by treatment with RDE.60 Both N-acetyl- and N-glycolloyl-neuraminic acid have been obtained by enzymic action on many differentcompounds (Table 3).That the same enzyme (RDE) liberates both sialicacids and also attacks a diacetylneuraminic acid-lactose (see below) indicatesa lack of specificity.62u Heimer and Meyer 273 28 found an RDE preparationalso to contain an enzyme system splitting methyl N-acetylneuraminidateinto N-acetyl-D-glucosamine and pyruvic acid (see above).This is confirmedby Popenoe and Drew 57 but not by Klenk.78 Neuraminic acid is notalways released by enzymes, nor does its presence in a molecule confer thepower to inhibit agglutination. Also, in inhibitory compounds the contentof neuraminic acid is not an index of inhibitory power. It is not itselfinhibitory, but is present in all inhibitor^.^^ Examples illustrating thesepoints are (i) BSM loses 64% of its sialic acid with RDE,79 but of five sialic77 J. F. McCrea, Yale J . Biol. apzd Aged., 1954, 26, 191.7 9 A. Gottschalk, ref. 4, p. 292.E. Klenk, ref. 4, p. 298328 BIOLOGICAL CHEMISTRY.acid-containing oligosaccharides from human milk only one was attackedby RDE. (ii) Orosomucoid,containing 12% of sialic acid, is not inhibitory and is not attacked byinfluenza virus but is attacked by RDE 81 (Table 3).Human-brainganglioside, containing 23% of N-acetylneuraminic acid, is not attackedby RDE.48y49 (iii) Human urinary mucoprotein ( 6 5 % of sialic acid) is astronger inhibitor than BSM (17% of sialic acid).82The physiological role of neuraminic acid in relation to the influenzavirus has been summarized as follows.83 " The influenza virus, for somereason, has chosen the neuraminic acid present in some areas of the hostcell membrane as its main anchorage and developed a complementarypattern at its own surface. Helpful as this mechanism is for the invasionof the host cell by the virus, the operation of the same mechanism wouldbe fatal to the virus progeny produced in the host cell and proceeding to thecell surface.Unless checked this mechanism would keep the newly formedvirus fixed to the cell surface and thus prevent its further reproduction.The possession by the virus of a neuraminidase overcomes the fatal situation.By enzymic removal of neuraminic acid from the host cell receptors theinfluenza virus releases itself and continues its life cycle by invading anothercell."Linkage of neuuraminic acid to carrier molecules. The mode of attachmentof neuraminic acid to its carrier molecules is now receiving attention. Theease of removal by acid and by enzymes indicates a terminal position.Mgs5It is probably significant that the sialic acids are frequently accompaniedby parallel amounts of hexosamine or hexose.24 For example, Blix et al.%showed that brain gangliosidide and BSM contain D-galactosamine andsialic acid in comparable amounts and suggested that in both substancesthe sialic acid is probably bound by an easily split linkage to the amino-sugar.In orosomucin there is no galactosamine but glucosamine is inequal amount with the sialic acid.41 The notions that in BSM the linkagewas (i) an amide bond involving the carboxyl group 34 and (ii) a glycosidiclinkage to the amino-group of galactosamine B6 have been abandoned.Each of these suggestions was based on the ease with which sialic acid isdetached by alkali, it being assumed that sialic acid alone was splitoff.Heimer and Meyer 27 found that the galactosamine of BSM is N -acetylated and Oncley et al.56 conclude that in orosomucoid " neuraminicacid appears to be the terminal sugar of the carbohydrate chains, whosecarboxyl group is free, and linked in an 0-glycosidic bond to the non-reducing end of N-acetylgalactosamine or galactose. There would appearto be no free a-amino-groups in the peptide moiety, and no free amino-groups in the galactosamine or neuraminic acid moiety. " Chrornato-graphic examination of alkali-treated BSM showed that it is a disaccharideNone of these five sugars was inhibitory.80F. Zilliken, ref. 4, p. 304.81 R. J. Winzler, ref. 4, p. 312.82 A. Gottschalk, ref. 4, p. 294.83 Idem, ref. 4, p. 291.O4 G. Blix, L.Svennerholm, and I. Werner, Acta Chem. Scaiad., 1952, 6, 358.A. Gottschalk, ref. 4, p. 291.Idem, Biochim. Biophys. Acta, 1956, 20, 560BADDILEY AND BCCHANAN : PURINE AND PYRIMIDINE RING SYSTEMS. 329which is released, in the form of N-acetylneuraminic acid linked to achromogen.87 This is split by influenza-virus enzyme into the N-acetyl-acid and the chromogen, the latter reacting instantly with cold Ehrlichreagent (see above). The same chromogen is formed when N-acetyl-galactosamine is treated with alkali. Since an N-glycosidic linkage isruled out Gottschalk 87 suggests that in BSM N-acetylneuraminic acid islinked to C(3) of N-acetylgalactosamine, the latter in turn being joinedthrough its reducing group to a polypeptide. Alkali cleaves the sugar-peptide bond and the disaccharide, being the glycoside of a p-hydroxy-aldehyde, is now itself alkali-labile and can be split into chromogen andN-acetylneuraminic acid.The chromogen is assumed to be acetylanhydro-galactosamine (cf. ref. 88) originating “ by loss of water and formation of adouble bond between C(2) and C(3).J’ If this is true it is not clear how theneuraminic acid and the chromogen can remain attached to each otherthrough Ct3) of the chromogen to form the disaccharide from which thevirus releases these two compounds (see above). The neuraminic acidmoeity of neuramine-lactose is also thought to be joined to C(3) of galactose.89W. J. W.4. THE BIOSYNTHESIS OF THE PURINE AND PYRIMIDINE RING SYSTEMS.THE steps involved in the biosynthesis of purine and pyrimidine ring systemsare probably better understood than are those for most other heterocyclicgroups which occur in Nature. This Report is mainly concerned with theintermediate stages which are now known to occur in the synthesis de nowof purines and pyrimidines.Although it is difficult to generalise in the fieldof biosynthesis, the balance of evidence suggests that there is one main routefor the formation of each ring system, through uridine-5’ phosphate andinosine-5’ phosphate ; the various pyrimidines, purines, and their nucleosidesor nucleotides which occur in Nature may be derived from these compoundsby substitution reactions. Enzyme systems are now known which are ableto carry out many, but not all, of these interconversions. As this aspect ofthe subject is developing so rapidly, and as the exact status in the living cellof some of these interconversions is not yet settled, this report deals mainlywith the biosynthesis of the fundamental ring systems.The Pyrimidine Ring.-The first evidence that the pyrimidine ring inpolynucleotides is built from small molecules was that of Barnes andSchoenheimer,l who showed that the nitrogen atom from 15N-labelledammonium citrate was incorporated into nucleic acid pyrimidines.Lagerkvist found that N,, of uracil (I) contained more than 3 times asmuch 15N as did No, when [15N]amm~nium salts were fed to rats.Carbondioxide 3 9 4 was shown to be the precursor of the C(d atom, while formateA. Gottschalk, Biochim. Biophys.Actu., 1957, 24, 649.R. Kuhn and G. Kruger, Ber., 1956, 89, 1473.8s A. Gottschalk, ref. 4, p. 304.1 F. W. Barnesand R. Schoenheimer, J . Biol. Chem., 1943, 151, 123.2 U. Lagerkvist, Arkiv Kenzi, 1953, 5, 569.M. R. Heinrich and D. W. Wilson. J . Biol. Chem., 1950, 186, 447.U. Lagerkvist, Actu Chem. Scund., 1950, 4, 1161330 BIOLOGICAL CHEMISTRY.was not specifically incorporated. I t was suggested, on the basis of workwith Neurospora m ~ t a n t s , ~ that oxaloacetate contributed to the main carbonchain in pyrimidines. Orotic acid (11) was found to replace pyrimidines asgrowth factors for Neurospora mutants 6 and for a Streptococcus.7 Its rdleH H Has a precursor in the rat was confirmed by Reichard and his co-workers,8using labelled orotic acid, and later by others for mammalian tissues 9,10and micro-organi~ms.~1-~~ Lactobacillus bulgaricus 09, an organism requiringorotic acid for growth, utilised labelled DL-carbamoylaspartic (ureidosuccinic)acid as effectively as orotic acid for the synthesis of nucleic acid pyrimidines.12This has been fully confirmed for other systems.14-16 Carbon-labelledaspartic acid was converted into polynucleotide pyrimidines by rat-liverslices l7 and there is some evidence that aminofumarodiamide is aprecursor of pyrimidine.5*15 Reichard and Lagerkvist 18 used the orotic acid-synthesising system of rat-liver slices l9 to examine the r81e of small moleculesin pyrimidine biosynthesis. Labelled precursors were incubated in thepresence of a pool of unlabelled orotic acid. In this way ammonia, carbondioxide, L-aspartic acid, and L-carbamoylaspartic acid were confirmed asprecursors.Tracer experiments have shown that the carbamoyl group ofcitrulline can be incorporated into pyrimidines,20-22 but only under con-ditions where an active urea-synthesising system is absent.l5, 23H. K. Mitchell and M. B. Houlahan, Fed. Proc., 1947, 6, 506.H. S. Loring and J. G. Pierce, J . Biol. Chem., 1944, 153, 61.H. J. Rogers, Nature, 1944, 153, 251.8 H. Arvidson, N. A. Eliasson, E. Hammarsten, P. Reichard, H. von Ubisch, andS. Bergstrom, J . Biol. Chela., 1949, 179, 169; P. Reichard, Acia Chem. Scand., 1949,3, 422; P. Reichard and S. Bergstrom, ibid., 1951, 5, 190.L. L. Weed and D. W. Wilson, J . Biol. Chem., 1951, 189, 435; L.L. Weed,Cancer Res., 1951, 11, 470.10 R. B. Hurlbert and V. R. Potter, J . Biol. Chew., 1952, 195, 257; 1954, 209, 1 ;E. Herbert, V. R. Potter, and L. I. Hecht, ibid., 1957, 225, 659; R. B. Hurlbert andP. Reichard, Acta Chem. Scand., 1954, 8, 701.11 L. L. Weed and S. S. Cohen, J . Biol. Chem., 1951, 192, 693.l2 L. D. Wright, C. S. Miller, H. R. Skeggs, J. W. Huff, L. L. Weed, and D. W.13 M. Edmonds, A. M. Delluva, and D. W. Wilson, J . Biol. Chem., 1952, 19'9, 251.l4 I. Lieberman and A. Kornberg, ibid., 1954, 207, 911.15 C. Cooper and D. W. Wilson, Fed. Proc., 1954, 13, 194; C. Cooper, R. Wu, and16 E. P. Anderson, C. Y. Yen, H. G. Mandel, and P. K. Smith, ibid., 1955, 213,17 U. Lagerkvist, P. Reichard, and G. Ehrensvard, Actu Chem.Scand., 1951, 5, 1212.1* P. Reichard and U. Lagerkvist. ibid., 1953, 7, 1207.lo P. Reichard, J . Biol. Chem., 1952, 197, 391.20 M. P. Schulman and S. J. Badger, Fed. PYOC., 1954, 13, 292.2l M. R. Heinrich, V. C. Dewey, and G. W. Kidder, J . Amer. Chem. SOC., 1964, 76,22 L. H. Smith and D. Stetten, ibid., p. 3864.23 P. Reichard, Acta Chem. Scand., 1954, 8, 795.Wilson, J . Amer. Chem. Soc., 1951, 73, 1898.D. W. Wilson, J . Biol. Chem., 1955, 216, 37.625.3102BADDILEY AND BUCHANAN : PURINE AND PYRIMIDINE RING SYSTEMS. 331The scheme of pyrimidine synthesis de novo is now believed to be:ATP + acetylglutamateNH, + C02 NH,-CO.O*PO,H, + ADPCOzH(1)(2) 1NH2*C0.0.P0,H2 + L-aspartate # NH,*C0.NH*CH-CH2*CO,H + H,PO,(5)(11) + (VI) (IV) + pyrophosphate +Reaction (1).This reaction was first described by Grisolia and C ~ h e n , ~ ~who called the product " Compound X " and believed it to be a glutamicacid derivative. Lipmann and his co-workers 25 synthesised carbamoyl di-hydrogen phosphate and showed it to be identical with an enzymicallyprepared sample. Despite some evidence to the contrary,26s27 it now seemsclear that " compound X " is carbamoyl dihydrogen phosphate.28, 29 Thefunction of acetylglutamate in the enzymic synthesis is obscure.The incorporation of the carbamoyl group of citrulline into pyrim-idines 20-22 has been shown to involve the formation of carbamoyl dihydrogenphosphate 273 30 as an intermediate, rather than argininos~ccinate.~~ Tworeactions were demonstrated 30 in rat liver :citrulline + H,PO, + carbamoyl dihydrogen phosphate + ornithine 25a 32y 33citrulline + ATP _t carbamoyl dihydrogen phosphate + ornithine + ADPLowenstein and Cohen 34 found that " Compound X ", nowknown to be carbamoyl dihydrogen phosphate, yielded carbamoylasparticacid with L-aspartic acid in rat-liver preparations. The results have beenconfirmed with liver 257 273 28 and Escherichia C O Z ~ .~ ~Lieberman and Kornberg,14 working with Zymobacteriumoroticum, were able to isolate dihydro-orotic acid (111), which was in enzymicequilibrium with L-carbamoylaspartic acid. Earlier nutritional studies hadReaction (2).Reaction (3).24 S. Grisolia and P. P. Cohen, J . Bid. Chem., 1953, 204, 753.25 M. E. Jones, L.Spector, and F. Lipmann, J . Amer. Chem. Soc., 1955, 77, 819.26 S. Grisolia, H. J. Grady, and D. P. Wallach, Biochim. Biophys. Acta, 1955, 17, 277.27 P. Reichard, L. H. Smith, and G. Hanshoff, Acta. Chem. Scand., 1955, 9, 1010.28 R. 0. Marshall, L. M. Hall, and P. P. Cohen, Biochim. Biophys. Acta, 1955,17,279.29 P. Reichard and G. Hanshoff, Acta Chem. Scand., 1956,10, 548.30 L. H. Smith and P. Reichard, ibid., 1956, 10, 1024.J. B. Walker and J. Myers, J . Bid. Chem., 1953, 203, 145; S. Ratner, W. P.Anslow, and B. Petrack, ibid., 1953, 204, 115.32 P. Reichard, Acta Chem. Scand., 1957, 11, 523.S3 H. A. Krebs, L. V. Eggleston, and V. A. Knivett, Biochem. J., 1965, 59, 185.34 J. M. Lowenstein and P. P. Cohen, J . Amer. Chem. Soc., 1954, 76, 5571; J .B i d .Chem., 1956, 220, 57332 BIOLOGICAL CHEMISTRY.been hampered by an erroneous synthesis of dihydro-orotic acid, but anauthentic sample,35 made from L-asparagine, had the expected growth-promoting properties for Lactobacillus bulgaricus 09.2. oroticum contains a DPN-dependent enzyme, dihydro-orotate dehydrogenase; 36g37 the equilibrium lies on the side of the dihydro-compound. Tracer l5 and growth experiments 35 show the presence of theenzyme in other systems. An E. coli mutant lacking this enzyme has beende~cribed.~7During work on the conversion of orotic acid into uridine-5’phosphate (V), a new phosphate of ribose,38 ribose 5-phosphate l-pyro-phosphate (VI ; PRPP), was discovered. The structure has been confirmedby synthesis.39Reaction (4).Reaction (5).O*PO,H,OH OHThis phosphate arises 38 from ribose 5-phosphate and ATP in pigeon ormammalian liver, yeast, and bacteria.Orotidylic pyrophosphorylase wasbest purified from yeast autolysates; 40 it required magnesium ions andshowed no reaction with uracil, cytosine, or dihydro-orotic acid. Thenucleotide (IV) was identified with the product of enzymic phosphorylationof ~rotidine.~lReaction (6). Orotidylic decarboxylase was also purified from yeast ; *Othe reaction appears to be irreversible.The reactions described are the main pathway of pyrimidine biosynthesis.Lieberman has demonstrated the conversion of uridine-5’ triphosphate intocytidine triph~sphate,~~ with ammonia, ATP, and an enzyme fromE. coli.The Purine Ring.-Early work on the synthesis de novo of the purine ringwas associated largely with the formation of uric acid, this being the chiefend-product of purine metabolism in birds and reptiles.Edson, Krebs, andModel43 showed that hypoxanthine is formed in pigeon liver, and this isoxidised to uric acid in the kidney. Orstrom, Orstrom, and KrebsU werea5 C. S. Miller, J. T. Gordon, and E. L. Engelhardt, J . Amtr. Chem. SOC., 1953, 15,a* I. Lieberman and A. Kornberg, Biochim. Biophys. Acta, 1953, 12, 223.8’ R. A. Yates and A. B. Pardee, J . Bid. Chem., 1956, 221, 743.A. Kornberg, I. Lieberman, and E. S. Simms, J . Amev. Chem. SOC., 1954, 76,G. M. Tener and H. G. Khorana, Chem. and Ind., 1957, 562.40 I. Lieberman, A. Kornberg, and E. S. Simms, J . Amer.Chem. Soc., 1964, 76,41 A. M. Michelson, W. Drell, and H. K. Mitchell, Proc. Nat. Acad. Sci. U.S.A.,4a I. Lieberman, J . Amev. Clzem. SOC., 1955, 77, 2661.43 N. L. Edson, H. A. Krebs, and A. Model, Biochem. J . , 1936, 30, 1380.44 A. Orstrom, M. Orstrom, and H. A. Krebs, ibid., 1939, 33, 990.6086.2027; J . Biol. Chem., 1955, 215, 389.2844; J . Biol. Chem., 1965, 215, 403.1951, 37, 396BADDILEY AND BUCHANAN : PURINE AND PYRIMIDINE RING SYSTEMS. 333'able to show that hypoxanthine is synthesised de now in pigeon-liver slices,and this was demonstrated later in cell-free liver extracts.45The sources of the carbon and nitrogen atoms in uric acid formed bypigeons were established by J. M. Buchanan and his collaborator~.~6~~ Inan earlier Report 5O this aspect of the subject was reviewed and it will sufficehere to describe the findings at that time and to discuss only the more recentdevelopments. By feeding small molecules containing 13C or 15N to pigeons,isolating uric acid, and degrading this specifically, it was found that thepurine ring originates in the following manner:C,), C(5), and N(7) arise mainly from glycine which is incorporatedf%:$ C(6) is from carbon dioxide." (It was shown later that other" one-carbon '' s0urces,~1-~~ e.g. from C(2) of glycine, threonine, and histidine,and C8) of serine, are also good sources of Ct2) and C(*) in purines. This isconsistent with the view that these are metabolically equivalent to formate.)The carbon atoms in hypoxanthine also arise from the same precursorsas those in uric acid; glycine, carbon dioxide, and formate are utilisedin the molar ratio 1 : 1 : 2 for the formation of this p~rine.~6The discovery that ammonia is readily incorporated into uric acid 1s 57did not clarify the biosynthetical route to the purines, since ammonia israpidly distributed into the general nitrogen pool, but these early isotopestudies dispelled older views that purines arose from pre-formed compoundswhich resembled purines.Shernin and Rittenberg 58 showed that thenitrogen of [15N]glycine is utilised mainly as a source of the N(,I atom inman, and a similar conclusion was reached by Buchanan, Sonne, andDelluva 4649 using pigeons. Similar experiments on hypoxanthine synthesisin liver extracts 2j 59 indicate that the N(,) atom is from glycine, atoms N(9)and N!B) are from the amide nitrogen of glutamine, and atom N,, is fromaspartic acid.6OBy use of isotopically labelled compounds Greenberg 61 demonstrated theoccurrence of a number of precursors of hypoxanthine in systems in vitro andconcluded that the immediate precursor of the purine is its nucleotide,as a unit.Ctz) and C(s) are from formate.ps G.R. Greenberg, Arch. Biochem., 1948, 19, 337.46 J. M. Buchanan, J. C. Sonne, and A. M. Delluva, J. Biol. Chem., 1948, 173, 81.47 J. C. Sonne, J. M. Buchanan, and A. M. Delluva, ibid., 1946, 166, 395.48 Idem, ibid., 1948, 173, 69.4 9 J. M. Buchananand J. C. Sonne, ibid., 1946 166, 781.5 0 R. Bentley, Ann. Repovts, 1948, 45, 239.51 D.Elwyn and D. B. Sprinson, J. B i d . Chem., 1950, 184, 466.5a D. B. Sprinson and D. Rittenberg, ibid., 1952, 198, 655.53 A. I. Krasna, P. Peyser, and D. B. Sprinson, ibid., p. 421.54 G. R. Greenberg, Arch. Biochem., 1948, 19, 337.55 Idem, J. Biol. Chem., 1951, 190, 611.56 M. P. Schulman, J. C. Sonne, and J. M. Buchanan, ibid., 1952, 196, 499.5 7 A. A. Plentl and R. Schoenheimer, ibid., 1944, 153, 203; K. Bloch, ibid., 1946,5 8 D. Shemin and D. Rittenberg, ibid., 1947, 167, 875; J. L. Karlsson and H. A.6B J. C . Sonne, I. Lin, and J. M. Buchanan, J . Amev. Chem. SOL, 1953, 75, 1518.6o L. N, Lukens and J. M. Buchanan, Fed. P ~ o c . , 1956, 15, 305,165, 477; C. Tesar and D. Rittenberg, ibid., 1947, 170, 36.Barker, ibid., 1949, 177, 597.G.R. Greenberg, J . Biol. Chem., 1951, 190, 611334 BIOLOGICAL CHEMISTRY.inosine-5' phosphate (XVI). The isolation and identification of the inter-mediates, all of which contain a D-ribofuranose 5-phosphate residue, wereachieved by J. M. Buchanan and by G. R. Greenberg and their associates.In some cases the enzymic interconversion of these intermediates has beenstudied in detail and the enzymes themselves have been partially purified.The scheme for the biosynthesis of inosined' phosphate is outlinedbelow.H2N ,,,.,,[$ + '"marate. .(XV) owl)Reagents: (i) Glutamine, (ii) glycine and ATP, (iii) " HCOzH 'I, (iv) glutamine and ATP,(v) ATP, (vi) COa, (vii) aspartate.Although it was suspected that a phosphorylated derivative of riboseis involved at a very early stage in the synthesis of inosine-5' phosphate,the nature of this intermediate was uncertain.The discovery that ribose&phosphate l-pyrophosphate (PRPP) is utilised in pyrimidine nucleotidebiosynthesis 3* suggested the mediation of this compound in the early stagesof purine nucleotide synthesis. It is now established that this phosphateparticipates in the synthesis of the two glycine derivatives (VIII) and (IX).Ribose &phosphate, format eglycine, glutamine, and ATP were known toreact in the presence of liver extracts to give glutamic acid, AMP, and twonew glycine derivatives.62 One of these (VIII) yielded glycine, ammonia,and ribose &phosphate on acid hydrolysis whereas the other (IX) yieldedformate in addition to these products.Both compounds have been isolatedpure G39 61 and their structures are probably as shown.G23 6 4 9 65 The natureof the glycosidic linkage has not been established but the p type would seemto be most probable in view of their biochemical function. There areindications that, when acidic conditions occur during their isolation, isomersare formed which may also act as nucleotide precursors under suitable82 D. A. Goldthwait, R. A. Peabody, and G. R. Greenberg, J . Amer. Chem. SOC.,1954, 76, 5258.8s Idem, J. Biol. Chem., 1956, 221, 555.64 S. C. Hartman, B. Levenberg, and J. M. Buchanan, J . Amer. Chem SOC., 1955,85 R A. Peabody, D. A. Goldthwait, and G. R, Greenberg, ibid., p. 1071,77, 501; J . Biol. Chem., 1956, 221, 1057BADDILEY AND BUCHANAN : PURINE AND PYRIMIDINE RING SYSTEMS.335enzymic conditions (mutarotation ?). Both the a and the @ form of N -glycyl-D-ribofuranosylamine have been synthesised from 2 : 3 : 5-tri-O-benzoylribofuranosylamine.66 The latter was obtained by reduction of thep-azide, and several methods were used for its condensation with glycinederivatives. The products differ from the natural compounds by thepresence of a phosphate group in the latter, so no direct comparison ofsynthetic and natural materials has been possible.Fractionation of the enzymes responsible for the synthesis of these glycinederivatives in pigeon liver has shown that the first step is a reaction betweenribose 5-phosphate and ATP to give the pyrophosphate (VI ; PRPP) .6 2 y 67 Thisthen reacts with glutamine to give ribofuranosylamine 5-phosphate (VII) andinorganic pyrophosphate.s* This intermediate has not been isolated and,in fact, is readily decomposed to ribose 5-phosphate and ammonia.69 Asynthetic material (from ribose 5-phosphate and anhydrous ammonia) couldbe substituted for (VII) in the enzymic synthesis of derivatives (VIII) and(IX) of glycine, and under these conditions glutamine is not r e q ~ i r e d . ~ ~ j 70The subsequent reaction between the mine (VII), glycine, and ATP hasnot been fully clarified ; adenosine diphosphate and inorganic phosphatewere produced in addition to the glycine derivative (VIII). Comparison ofthe biosynthetical scheme outlined so far with the isotope distribution inuric acid or hypoxanthine illustrates how glycine is incorporated as an intactunit and how the amide nitrogen of glutamine provides the N,,, atom.Thecompletion of the glyoxaline ring of the purine requires the introduction ofC(2) (i.e. in the purine) as formate or its biochemical equivalent. Theenzymic formylation of the glycine derivative (VIII) to give (IX) is knownto occur with formate. A folic acid derivative is also required in thisreaction.6' An intermediate, believed to be a formylated derivative oftetrahydrofolic acid, is formed from formate, tetrahydrofolic acid, and ATP.This is then able to formylate the glycine derivative (VIII).62 The formylgroup of the anhydroleucovorins 71 is also able to act as a source of formylgroup in the formation of (IX).The enzyme for this reaction is known asglycineamide ribotide transformylase. The process of formylation at thisstage in the biosynthesis is similar to one which occurs later. This aspectof the scheme has been reviewed by Greenberg and Jaeni~ke.'~When the formyl derivative (IX) is treated with glutamine and ATP inthe presence of a fractionated liver-enzyme preparation an amidine isformed.73* 74 The nature of its hydrolysis products and its position in thebiosynthetical scheme indicate that it is the derivative (X) of the amidine ofglycine. The need for ATP in the synthesis of this amidine suggests the66 J. Baddiley, J. G. Buchanan, R. Hodges, and J . F. Prescott, Proc. Chem. SOC.,1957, 148; J . , 1957, 4769.6 7 D. A. Goldthwait, R.A. Peabody, and G. R. Greenberg. J . Bid. Chenz., 1956,221, 569.68 Idem, Biochim. Biophys. Acta, 1955, 18, 148.6Q D. A. Goldthwait, J . Biol. Chem., 1956, 222, 1051.70 S. C. Hartman, F e d . Proc., 1956, 15, 269.71 L. Warren and J . G. Flabs, F e d . Proc., 1956, 15, 379.72 G. R. Greenberg and L. Jaenicke, Ciba Foundation Symposium, " Chemistry and74 I. Melnick and J . M. Buchanan, ibid., 1957, 225, 157.Biology of Purines," Churchill, London, 1957, p. 204.B. Levenberg and J. XI. Buchanan, J . Biol. Chern., 1957, 224, 1019336 BIOLOGICAL CHEMISTRY.occurrence of a phosphorylated intermediate, but this has not yet beenobserved. The nitrogen atom introduced at this stage (N,,, in the finalpurine) originates from the amide nitrogen of glutamine, again in agreementwith the earlier isotope studies.It is interesting that the antimetabolites azaserine 75 (0-diazoacetyl-L-serine) and 6-diazo-5-oxonorleucine (DON) strongly inhibit synthesis in vitroof purines, 76 causing accumulation of both N-glycylribosylamine 5-phosphate(VIII) and its formyl derivative (IX).6$ The antimetabolites are competitiveinhibitors of glutamine metabolism and consequently affect the conversionof the formylglycine amide derivative (IX) into the amidine (X).Thiscauses accumulation of both (VIII) and (IX).M* 77* 78Stetten and Fox's observation 79 that a base, later identified as 5-amino-glyoxaline-4-carboxyamide (XVII) ,80 accumulated in the medium ofsulphonamide-inhibited E. coli led to suggestions that this might be a purineprecursor. Although the carboxyamide is readily converted into hypo-xanthine in pigeon-liver extracts 81 and is a precursor of adenine and guaninein rats 82 or uric acid in pigeons,= it could be shown that it is not on thedirect pathway to these purines.With the discovery that derivatives ofribose phosphate are involved in purine synthesis and that inosine-5'phosphate is a key intermediate, it was considered possible that a ribosephosphate of the carboxyamide might be a nucleotide precursor.61 Thisview was shown to be correct by Greenberg 84 who isolated the N-ribo-furanosyl derivative of this base from sulphonamide-inhibited E. coli. 859 86Its structure was proved by hydrolysis to the free base and ribose and byits chemical conversion into inosine. A chemical synthesis of the ribosylderivative has been de~cribed.8~ This involved conversion of methyl5-nitroglyoxaline-4-carboxylate into the isomeric 2 : 3 : 5-tri-O-benzoyl-ribosyl derivatives (XVIII) and (XIX).The isomer (XVIII) was treatedwith ammonia and the resulting amide hydrogenated to the ribosyl compoundwhich was identical with the natural one. In an independent synthesis 88benzylation of inosine gave the l-benzyl derivative (XX), which with alkaliwas converted into an N-benzylcarboxyamide. Removal of the benzylgroup with sodium in liquid ammonia gave the carboxyamide.Accompanying the ribosyl derivative, which has since been found in76 Q. R. Bartz, C. C. Elder, R. P. Frohardt, S. A. Fusari, T. H. Haskell, D.W.7 6 H. E. Skipper, L. L. Bennett, and F. M. Schabel, Fed. Proc., 1954, 13, 298.'7 B. Levenberg and J. h1. Buchanan, J . Amer. Cltem. SOC., 1956, 78, 504.78 B. Levenberg, I. Melnick, and J. M. Buchanan, J . Biol. Chem., 1957, 225, 163.7 9 C. L. Fox, Proc. SOG. Exp. Biol. filed., 1942, 51, 102; M. R. Stetten and C . L.W. Shive, W. W. Ackermann, M. Gordon, M. E. Getzendaner, and R. E. Eakin,M. P. Schulman and J . M. Buchanan, J . Biol. Chem., 1952, 196, 513.Johannessen, and A. Ryder, Nature, 1954, 173, 72.Fox, J . Biol. Chevn., 1946, 161. 333.J . Anter. Chem. Sac., 1947, 69, 725.82 C. S. Miller, S. Gurin, and D. W. Wilson, Science. 1050, 112, 654.83 M. P. Schulman, J. M. Buchanan, and C. S. Miller, Fed. Proc., 1950, 9, 225.84 G. R.Greenberg, ibid., 1953, 12, 211.85 Idem, J . Amer. Chem. SOC., 1952, 74, 6307.137 J. Baddiley, J. G. Buchanan, and J. Stewart, Proc. Chem. SOC., 1957, 149.G. K. Greenberg and E. L. Spilman, J . Biol. Chesn., 1956, 219, 411.E. Shaw, 16th International Congress of Pure and Applied Chemistry, Paris,l957, Communications, Vol. 11, p. 276BADDILEY AND BUCHANAN : PURINE AND PYRIMIDINE RING SYSTEMS. 337E. coli mutants requiring purines,899 90 are smaller amounts of its 5’-phosphate(XIV).86s 89 This phosphate is readily formed from the ribosyl derivativeby the action of ATP and a kinase from brewer’s ~ e a s t . ~ 1 It is readilyH RHzN*OC H2N[;> .P,:x>RIXVII) (XVIII) ( X I X )OHR = tri-0-benzoyl-D-ri bofuranosylconverted into inosine-5’ phosphate in pigeon-liver preparations.It isgenerally considered that the phosphate is a true precursor in the bio-synthetical scheme, whereas the ribosyl derivative and the free base aredegradation products. Further support for this view is given by the findingthat nucleoside phosphorylase from beef liver will convert the free base andribose 1-phosphate into the nucleoside; 92 the phosphate (XIV) is alsoformed from the base and ribose 5-phosphate I-pyrophosphate (PRPP) .93Analogous reactions between PRPP and hypoxanthine, adenine, guanine ,and 6-mercaptopurine yield the appropriate nucleotides. Such reactionsare probably concerned in the direct incorporation of purine bases from thediet into nucleotides and nucleic acids. Ribose 1 : 5-diphosphateJ oncethought to be involved in this type of reaction, is not active in these systems.94The intermediate stages in the conversion of the glycine derivative(VIII) into the aminoglyoxaline nucleotide (XIV) , proceeding through theformyl derivative (IX) and the amidine (X), have now been elucidated.When the fonnyl derivative (IX) is incubated with liver extracts and glut-amine, carbon dioxide, aspartate, ATP, and a source of formyl groups aready synthesis of inosine-5’ phosphate ensues.By omission of appropriatecompounds intermediates accumulate. With ATP and glutamine the amino-glyoxaline derivative (XI) is formed. 95 When purified enzyme systems areused, the first step is formation of the amidine (X), which with ATP cyclisesto the glyoxaline (XI).73 The structure of the aminoglyoxaline was based onanalysis, spectra, and biosynthetical function, since it readily gave inosine-5‘phosphate under suitable enzymic conditions.The ribosyl compound cor-responding to (XI) is identical with a compound isolated from the medium of apurine-requiring mutant of E. coli by Love and GotsJ98 and is closely relatedto an arylamine detected by Chamberlain, Cutts, and Rainbow 97 in a yeastgrowing with suboptimal levels of biotin. It is believed that the phosphate isthe true nucleotide precursor, the ribosyl compound having arisen by the8Q J. S. Gots, Nature, 1953, 172, 256.go J. M. Weaver and W. Shive, J . Amer. Chem. Sot., 1953, 75, 4628.91 G. R. Greenberg, J . Biol. Chem., 1956, 219, 423.Q2 E.D. Korn, F. D. Charalampous, and J. M. Buchanan. J . Anaev. Chem. SOL,Q3 J . G. Flaks, M. J. Erwin, and J. M. Buchanan, ibid., 1957, 928, 201.94 Cf. J. M. Buchanan, J. G. Flaks, S. C. Hartman, B. Levenberg, L. N. Lukens.95 B. Levenberg and J. M. Buchanan, J . Bid. Chem., 1957, 224, 1005.O 6 S. H. Love and J. S. Gots, ibid., 1955, 212, 647.1953, 75, 3610; E. D. Korn and J. M. Buchanan, J. Biol. Chem.. 1955, 217, 183.and L. Warren, ref. 72, p. 233.N. Chamberlain, N. S. Cutts, and C . Rainbow, J. Gen. Microbid., 1952, 7, 64;N. Chamberlain and C. Rainbow, ibid., 1954, 11, 180338 BIOLOGICAL CHEMISTHY.action of phosphatases on this. It is interesting that the free base, 4(5)-aminoglyoxaline, is a product of degradation of purines by micro-organisms.98The conversion of the aminoglyoxaline (XI) into the aminoglyoxaline-carboxyamide (XIV) involves at least three steps.First a carboxylation tothe amino-acid (XII) occurs in the presence of hydrogen carbonate ion anda liver enzyme.99 The amino-acid has been isolated and its structureproved.loO The incorporation of isotope from [14C]carbon dioxide into thecarboxyl group of this acid is consistent with the earlier observation thatthe C(sl atom of the purine originates from carbon dioxide. The amino-acidreacts with aspartic acid and ATP to give the succinic acid derivative (XIII).The enzyme responsible for the cleavage of the latter to the ribose 5-phosphate derivative of 5-aminoglyoxaline-4-carboxyamide (XIV) andfumaric acid is probably adenylosuccinase.101 An earlier report 99 that theproducts include malic acid has been explained by the presence of fumarasein the unpurified enzyme preparations. There are indications that biotinmay be concerned in the processes leading from the aminoglyoxaline (XI)to the carboxyamide (XIV) .lo2 Saccharomyces cerevisiae accumulates amino-glyoxaline in conditions of biotin deficiency. It is not known whether thisis a direct action on the carboxylation process or whether it is indirect, biotinbeing perhaps involved in the synthesis of aspartate.Biotin has previouslybeen implicated in both carbon dioxide fixation and ammonia a~similation.10~The final stages of the biosynthesis of inosine-5' phosphate (XVI) includethe formylation of the amino-group in (XIV) to give the formamido-com-pound (XV), and its subsequent cyclisation.Earlier work on the effects ofsulphonamides indicated that folic acid derivatives are probably concernedin the metabolism of single-carbon 80~104 and this has beenconfirmed for purine biosynthesis by the observation that leucovorin(N5-formyltetrahydrofolic acid) stimulates the exchange of [14C]formate withthe 2-position of inosine-5' phosphate.lo5 However leucovorin requires ATPin order to maintain its effect as a catalyst 1O691O7 and it is believed that thetrue cofactor (CoF) in the transformylase reaction is a related derivative oftetrahydrofolic acid. The citrovorum factor and other folic acid derivativesare active in suitable circumstances in the formylation process which, likethat described earlier in the synthetical scheme, can utilise either formateor the p-carbon atom of serine.The nature of the formylation co-factors 729 106-108 is outside the scope of this Report, as is also the mechanismof serine incorporation. 72~1089 log98 J. C. Rabinowicz and W. E. Pricer, J . Biol. Chem., 1956, 222, 537.99 L. N. Lukens and J. 11.1. Buchanan, Fed. Proc., 1956,15, 305.loo Idem, J . Amer. Chem. SOC., 1957, 79, 1511.101 R. W. Miller, L. N. Lukens, and J. M. Buchanan, ibid., p. 1513.l o 2 A. G. Moat, C . N. Wilkins, and H. Friedman, J . Biol. Chem., 1956, 223, 985.103 H. C. Lichstein, Vitamins and Hormones, 1951, 9, 27.l o 4 W. Shive and E. C. Roberts, J . Biol. Chem., 1946, 162, 463.lo5 J. M. Buchanan and M.P. Schulman, ibid., 1953, 202, 241.lo6 G. R. Greenberg, J . Amer. Chem. SOC., 1954, 76, 1458.I07 Idem, Fed. Proc., 1954, 13, 745.lo8 Idem, ibid., 1953, 12, 651; G. R. Greenberg, L. Jaenicke, and M. Silverman,Biochim. Biophys. Acta, 1955, 17, 589; L. Jaenicke, ibid., p. 587.L. Jaenicke, Fed, Proc., 1956, 15, 281; J. G. Flaks and J. M. Buchanan, J .Amer. Chem. SOC., 1954, 76, 2275; J. G. Flaks, L. Warren, and J. M. Buchanan, J .Biol. Chem., 1957, 228, 215ARNSTEIN : THE BIOSYNTHESIS OF PENICILLIN. 339Enzymic routes have been established for the interconversion of inosine-5’phosphate and other purine nucleotides and these are probably the usualroutes for the biosynthesis of these compounds. havedescribed an enzyme, adenylosuccinase, which catalyses the reversibleformation of the adenyl-succinic acid (XXI) from adenosine-5’ phosphateand fumarate. Abrams and Bentley 111 noted the conversion of inosine-5’phosphate into adenosine-5’ phosphate and considered that the adenyl-succinic acid was an intermediate :Carter and CohenIt has been suggested 112 that an alternative path to adenosine-5’ phosphatemight occur at the glyoxaline stage.Amination of the succinic acidderivative (XIII) may give an amidine which could then yield, throughformylation and ring-closure, the adenyl-succinic acid. The mechanism ofthe conversion of inosine-5’ phosphate into guanosine-5’ phosphate has beendescribed by several investigators.llly113 A diphosphopyridine nucleotide-catalysed oxidation to xanthosine-5’ phosphate is followed by a transfer ofthe amide nitrogen of glutamine to the %position.J.B.J. G. B.5. THE BIOSYNTHESIS OF PENICILLIN AND SOME OTHER ANTIBIOTICS.MANY antibiotics have novel and interesting structures and their biosynthesishas received increasing attention in recent years. It is inevitable thatsome of the present concepts are still based on considerations of structuralfeatures and similarities rather than on direct experimental evidence ofbiogenetic mechanisms. Further work concerning the latter is clearlydesirable and it is hoped that this discussion will indicate some of the gapsto be filled, as well as the extent of present knowledge.Antibiotics related to Amino-acids and Peptides. Penicillin.-Relation ofpenicillin formation to the general metabolism of Penicillia. Three distinctmetabolic phases can be distinguished, viz., rapid growth of mycelium,no C.E. Carter and L. H. Cohen, J. Amer. Chem. SOC., 1955, 77, 499; J . Biol.Chem., 1956, 222, 17.ll1 R. Abrams and M. Bentley, J. Amev. Chem. SOC., 1955, 77, 4179; Arch. Bio-chem. Biophys., 1955, 58, 109.112 C. E. Carter and L. H. Cohen, Fed. Proc., 1955, 14, 189.113 U. Lagerkvist, Acta Chem. Scund., 1956,9, 1028; L. B. Gehrig and B. Magasanik,J . Amer. Chem. SOL., 1955, 77, 4685; B. Magasanik and M. S. Brooke, J . Biol. Chem.,1954, 206, 843-40 BIOLOGICAL CHEMISTRY.followed by restricted growth with penicillin formation, and finallyauto1ysis.l Penicillin is, however, not derived from a storage materialsynthesized during rapid growth, but is synthesized de wuoo from simpleprecursors, as shown by tracer experiments in which labelled precursorswere added either after growth had almost ceased or to fully-grown washedrnyceli~m.~ Penicillin is excreted by the cells into the culture medium, lessthan 1% being retained inside the rnyceli~m.~ The stability of penicillinin fermentations may vary with the strain of PeniciZJiwn and possibly withexperimental conditions.Only negligible destruction of [35S, 14C]penicillinwas observed during a period from 68 to 98 hours after inoculation of afermentati~n.~ In other experiments, appreciable destruction of benzyl-penicillin labelled with deuterium occurred throughout the course of thefermentation .6Side-chain precursors.Early experiments showed the utilization ofaliphatic and aromatic carboxylic acids and related compounds as side-chain precursors. On synthetic media, PeniciZEium chrysogenum producesthe so-called natural penicillins, which have aliphatic side-chains (I; R =pent-2-enyl, n-heptyl, n-pentyl, n-butyl, n-propyl, and traces of otherpenicillins of uncertain structure) .8 In addition, the fungus CephaZo-sporz‘um produces penicillins with D-a-aminoadipic acid as the side-chain.The relative proportions of aliphatic penicillins can be markedly alteredby supplementing media with the appropriate acids, e.g., hex-3-enoic acidas a precursor of pent-2-enylpenicillin.8 Many organic acids, or their(R = Ph-CH, in benzylpenicillin; the broken lines indicate its metabolic origin fromphenylacetic acid, cyst(e)ine, and valine.)derivatives, such as amides and 2-hydroxyethylamides, also give rise topenicillins containing the appropriate side-chain 1O-I3 and derivatives ofphenylacetic acid present in corn-steep liquor l4 similarly influence the typeand yield of penicillin.Phenylacetic acid labelled with deuterium l5 orH. R. V. Arnstein and P. T. Grant, Bacteriol. Rev., 1956, 20, 133.Idem, Biochem. J . , 1954, 57, 353.W. J. Halliday and H. R. V. Arnstein, ibid., 1956, 64, 380.A. L. Demain, Antibiotics and Chemotherapy, 1957, 7, 359.H. R. V. Arnstein, Giorn. Microbiol., 1956, 2, 268.A. L. Demain, klytibiotics and Cherrzotherapy, 1957, 7, 361.0. K. Behrens,J. A. Thorn and M. J. Johnson, J .Amer. Chem. Soc., 1950, 72, 2052.E. P. Abraham, Giorn. Microbiol., 1966, 2, 102.The Chemistry of Penicillin,” Edited by H. T. Clarke, J. R.Johnson, and Sir Robert Robinson, Univ. Press, Princeton, 1949, p, 657.lo J. W. Corse, R. G. Jones, Q. F. Soper, C. W. Whitehead, and 0. K. Behrens,l1 R. G. Jones, Q, F. Soper, 0. K. Behrens, and J. W. Corse, ibid., p. 2843.l2 J. H. Ford, G. C . Prescott, and D. R. Colingsworth, ibid., 1950, 72, 2109.l3 K. Singh and M. J. Johnson, J . Bacteriol., 1948, 56, 339.l4 T. H. Mead and M. V. Stack, Biochem. J., 1948, 42, xviii.J . Amer. Chem. SOC., 19$8, 70, 2837.0. K. Behrens, J. Corse, R. G. Jones, E. C. Kleiderer, Q. F. Soper, F. R. VanAbeele, L. M. Larson, J. C . Sylvester, W. J. Haines, and H. E. Carter, J .Biol. Chem.,1948, 175, 765ARNSTEIN : THE BIOSYNTHESIS OF PENICILLIN. 341isotopic carbon 16917 is incorporated into benzylpenicillin, and the increasedyields of penicillin are therefore not due to an indirect effect, for exampleon the enzymes involved in penicillin biosynthesis.Other effective penicillin precursors are substituted mercaptoacetic,ls$ l9hydroxyacetic ,18 polycyclic-acetic,ll heterocyclic-acetic,lly l3 and phenyl-aceticlo, l9 acids. Although the biosynthesis of some 40 unnatuxal penicillinshas been achieved, benzylpenicillin (penicillin G) and phenoxymethylpenicillin(penicillin V) are the only major commercial products, although allylthio-methylpenicillin (penicillin 0) is also produced in the United States.The relation of structure to precursor function may be summarized asfollows (cf.ref. 7). The best precursor is phenylacetic acid, but the phenylgroup may be substituted or replaced by other ring systems, except nitrogen-containing heterocycles. Benzoic acid is not utilized and usually onlymono-substituted acetic acids are effective. An cc-methylene group maybe essential for steric reasons since the only exception appears to be a-methyl-butyric acid; replacement of the methyl group by an ethyl or larger groupresults in loss of precursor activity.20 In the absence of a ring system,compounds containing an " interrupting group," for example a sulphidelinkage19 or a double bond, which would minimize @-oxidation, are goodprecursors. In the case of aliphatic acids, triglycerides have been success-fully used as a source of fatty acids which would otherwise be either toxicor metabolized too quickly to be available as penicillin precursors.20Oxidation of the phenyl group can occur, probably before incorporationof the precursor, giving p-hydroxybenzylpenicillin or P-hydroxyphenoxy-me thylpenicillin.21Although both Penicillium and Cephalosporium are able to synthesizethe same thiazolidine-p-lactam ring structure, P.chrysogenum WIS 49-133is apparently unable to utilize D-a-aminoadipic acid for biosynthesis ofcephalosporium N, whilst Cephalosporium Brotzu strain failed to synthesizebenzylpenicillin or any other solvent-soluble penicillin in response to theaddition of phenylacetamide.22Early studies werebased on the assumption that the addition of precursors of the penicillinring structure to a penicillin-producing fermentation would increase theyield, as in the case of side-chain precursors, but no conclusive results wereobtained.7923 It is evident, however, that only precursors which are rate-limiting for penicillin formation would be stimulatory.More recent workhas, therefore, been carried out with isotopically-labelled compounds,Precursors of the thiaxolidine-@-lactam ring system.l6 J. T. Craig, J. B. Tindall, and M. Senkus, Analyt. Chem., 1953, 23, 332.l' M. Gordon, S. C. Pan, A. Virgona, and P. Numerof, Science, 1953, 118, 43;0. K. Sebek, Proc. SOC. Exp. Med., 1953, 84, 170.Q. F. Soper, C. W. Whiteland, 0. K. Behrens, J. W. Corse, and R.G . Jones,J . Amer. Chem. SOC., 1948, 'SO, 2849.l9 0. K. Behrens, J. Corse, J. P. Edwards, L. Garrison, R. G. Jones, Q. F. Soper,F. R. Van Abeele, and C. W. Whitehead, J. Bid. Chem., 1948, 175, 793.2o D. C. Mortimer and M. J. Johnson, J . Amer. Chem. SOC., 1952, 74, 4098.21 J. De Flines, J. M. Waisvisz, I. Hoette, and A. P. Struyk, Antibiotics and Chemo-therapy, 1957, 7 , 497.22 C . W. Hale and G. A. Miller, personal communication.23 H. W. Florey, E. Chain, N. G. Heatley, M. A. Jennings, A. G. Saunders, E. P.Abraham, and M. E. Florey, " Antibiotics," Oxford Univ. Press, London, 1949, p. 965342 BIOLOGICAL CHEMISTRY.since consideration of rate-limiting steps is not required for interpretingsuch tracer experiments.Possible sulphur-containing precursors were studied by comparing theuptake of sodium [35S]sulphate into penicillin in their presence and absence.The sulphur of L-cystine was preferentially used, but neither D-cystine norDL-penicillamine affected the uptake of labelled sulphate.24 The resultswith L-cystine were confirmed in a similar experiment with ~-[~~S]cystineand unlabelled ~ u l p h a t e .~ ~ The equal incorporation of isotopic carbon,nitrogen, and sulphur from L-[P-~~C : 15N : 35S]cystine at C(5), the side-chainnitrogen, and the sulphur of penicillin 25 showed utilization of the intactamino-acid. In a similar fermentation, ~ - [ p - l ~ C : l ~ N : 35S]cystine was apoor precursor indicating the stereochemical specificity of penicillin bio-synthesis from ~ y s t i n e .~ ~ It is of interest that addition of cystine to washedmycelium of P. chrysogenum consistently increased penicillin yields,26although in complete fermentations no definite stimulation was ob~erved.~'The a- and p-methyl analogues of cystine are not converted into methyl-substituted penicillins.26and distribution of isotopes in the penicillin molecule 25 are compatible withthe metabolic pathway: glycine serine + cystine _t penicillin.The incorporation of [14C]formate into penicillin 28 may be explained bythe well-known participation of formate in the glycine-serine interconversion.The utilisation of methionine sulphur for penicillin biosynthesis in preferenceto sulphate but not to cystine 24 is consistent with the conversion of sulphateinto penicillin by the pathway: sulphate + intermediates - meth-ionine __t cystine __t penicillin.1The carbon chain of the penicillamine portion of the penicillin moleculeis derived from valine. The incorporation of 14C-labelled valine takesplace with similar dilutions of isotope (due to endogenous synthesis ofunlabelled valine) to those found with labelled cystine,2 and the distributionof radioactivity in penicillin derived from ~~-[carboxy-~~C]valine 29 andgenerally-labelled ~-[l~C]valine 30 indicates that the carbon chain of valineis used intact.The source of the thiazolidine nitrogen atom of penicillinand the stereochemical configuration of the valine used for penicillin bio-synthesis have, however, been more difficult to establish.In early experi-ments with [2H]phenylacetyl-~~-[15N]~aline,15 the isotopic nitrogen wasincorporated into penicillin with a far greater dilution than was deuterium,suggesting extensive loss of d i n e nitrogen before the utilization of theamino-acid. This interpretation is supported by a marked decrease in the15N : 14C isotope ratio during the incorporation of DL-[I~~N : a-14Cj valine intopeni~illin.~~ Since valine isolated from mycelial protein also had a low24 C . M. Stevens, P. Vohra, E. Inamine, and 0. A. Roholt, J . Biol. Chem., 1953,205, 1001.25 H. R. V. Arnstein and P. T. Grant, Biochent. J., 1954, 57, 360.26 H. R. V. Arnstein and H. Margreiter, ibid., 1958, 68, 339.27 R. W. Stone and M. A. Farrell, Science, 1946, 104, 445.28 E.Martin, J. Berky, C. Godzesky, P. Miller, J. Tome, and R. W. Stone, J . Bid.2s C. M. Stevens, P. Vohra, and C. W. De Long, zbid., 1954, 211, 297.30 H. R. V. Arnstein and M. E. Clubb, Biochem. J., 1957, 65, 618.The efficiency of incorporation of DL-[ @-14C]serine and [a-14C]glycineChem., 1953, 203, 239ARNSTEIN : THE BIOSYNTHESIS OF PENICILLIN. 343content of 15N relative to that of 14C, it is probable that extensive trans-amination of valine occurs under these c~nditions.~O However, l*C-labelledL-valine is converted into penicillin in complete fermentations much morerapidly than is ~-valine,~l and in experiments with washed mycelium~-[carboxy-~~C]valine was also a better precursor than the o-enanti~morph.~~Although the relatively poor utilization of D-valine under these conditionscould be due to the more rapid uptake of L-valine by the cellsJ30 otherevidence indicates that D-valine must be excluded as a precursor of penicillin.Thus, D-valine inhibits penicillin production by lactose-grown cells of astrain of P.chrysogenum, whilst L-valine has no effect at similar concen-t r a t i o n ~ . ~ ~ Also, the inhibition of penicillin production by a-methyl-DL-valine can be reversed by L-valine 32 and the conversion of labelled D-valineinto penicillin is inhibited by a-methylvaline to a significantly greaterextent than that of L-valine.26 Moreover, when the incubation period isshort , ~-[l~N]valine is incorporated into penicillin with relatively little lossof isotope,33 suggesting that deamination or transamination of valine isnot obligatory for penicillin formation.The foregoing results indicate that penicillinis built up by condensation of L-cystine (or cysteine), L-valine, and anappropriately substituted acetic acid (see formula I).It follows, therefore,that the D-configuration at is introduced at some stage after reaction ofL-valine with cyst (e)ine or a derivatine of this amino-acid.It has been suggested3* that, by analogy with the biosynthesis ofcystathionine by the Neurospora, the sulphide bond of penicillin may beformed by condensation of L-cysteine with p-hydroxyvaline (11) to give(3 p-dimethyl-lanthionine (111) (see Fig. 1). However, p-hydroxy-DL-vaheis not a precursor of the penicillamine moiety of penicillin, although it isutilized indirectly for synthesis of the (3-lactam portion, presumably aftercleavage into glycine and acetone.30 Moreover, p (3-dimethyl-lanthioninehas also been excluded as an intermediate 35 and neither " cyclic " cysteinyl-valine (IV) nor its phenylacetyl derivative was active as a penicillin pre-cursor.36 It appears, therefore, that none of the possible alternatives ofpathway A (Fig.1) is involved in penicillin biosynthesis.The intact utilization of N-phenylacetylcysteine (VI) by pathway B(Fig. 1) has also been eliminated by experiments with di-N-[~arboxy-~~C]-phenylacetyl-~-[~~S]cystine,~~ although the possibility was not excludedthat phenylacetylcysteine may not be in reversible equilibrium with thedisulphide. In addition, the assumption that synthesis of diphenylacetyl-cystine by the mould would result in the excretion of at least some of thiscystine derivative into the extracellular medium may not be valid.Biosynthzetical mechanism.31 C.M. Stevens, E. Inamine, and C. W. De Long, J. Biol. Chem., 1956, 219, 405.32 A. L. Demain, Arch. Biochem. Biophys., 1956, 64, 74.33 C. M. Stevens, personal communication; C. M. Stevens and C. W. De Long,34 D. J. D. Hockenhull, K. Ramachandran, and T. K. Walker, Arch. Biochem.,36 C. M. Stevens, P. Vohra, J. E. Moore, and C. W. De Long, J. B i d . Chem., 1954,36 H. R. V. Arnstein and M. E. Clubb, Biochem. J.,,d1958, 68, 528.37 H. R. V. Arnftein, M. Clubb, and P. T. Grant, Proceedings 2nd RadioisotopeJ . Biol. Chem., 1958, in press.1949, 23, 160.210, 713.Conference, Oxford, Buttenvorths, London, 1954, 1, 306u-u,I 0 7 10 yIYz ac ...IN 'T'c?,al .r! (c% - ohc( .t Is .rlT - - m xARNSTEIN : THE BIOSYNTHESIS OF PENICILLIN.345Cystine labelled with tritium in either a- or @-position is converted intopenicillin with loss of only one of the two @-hydrogen atoms, whilst thea-hydrogen atom is retained.38 These results exclude the participation ofup-dehydrocystine derivatives, and are compatible with pathway C (Fig. 1)or an essentially similar alternative mechanism.38 According to thisscheme, cysteinylvaline (or the disulphide) and the fused thiazolidine-@-lactam structure (V) are the only stable intermediates and the D-configurationof C(31 of penicillin is introduced during closure of the thiazolidine ring.Several years ago, compound (V) (named penicin) was reported to be formedby cultures of Penicillium chrysogenum Q176 in the absence of phenylaceticacid as a side-chain precursor 39 or by enzymic hydrolysis of benzylpeni-cillin.40 Although these claims have so far not been confirmed, it seemsquite possible that acylation of (V) does indeed represent the final step inpenicillin bios yn t hesis.Attempts to isolate and identify possible intermediates have so far beenunsuccessful.At least some of the intermediates involved in penicillinbiosynthesis may not be freely diffusible, since mutants of Peaicilliumclzvysogevturn whose synthetical capacity has been impaired fail to producepenicillin in mixed culture, although normal penicillin production is restoredin the heterokaryotic or heterozygous c~ndition.~l The mycelium of P.chrysogenurn contains several sulphur compounds, of which the majorconstituent has been identified as choline s u l ~ h a t e .~ ~ Several cystinepeptides have also been detected, but their structure and significance inpenicillin biosynthesis have not yet been determined.43Other Antibiotics related to @ystine.-Structural considerationssuggest that several antibiotics other than penicillin may be derivedbiogenet icall y from cystine.Szibtilin. p-Methyl-lantionine (VII) has been isolated from an acidhydrolysate of s u b t i k U This compound is identicalM with an amino-acid from the antibiotic risin 45 and its chromatographic properties aresimilar to those of an amino-acid from cinnamycin.46 The configurationof the two a-carbon atoms is analogous to the corresponding asymmetricP aH 0,C.C H (N H z ) C H,S* C H Me * C H ( N H ,) * COz HL D(VWcentres of penicillin (C, and and it is possible that L-cystine reactswith a-aminobutyric acid in a similar way, as with valine in penicillin38 H.R. V. Arnstein and J. C. Crawhall, Biochenz. J., 1957, 67, 180.a s K. Kato, J . Apztibiot., 1953, A , 6, 130, 184.41 G. Sermonti, J . Gen. Microbiol., 1956, 15, 599.42 J. De Flines, J . Amer. Chem. SOC., 1955, 77, 1676.43 H. R. V. Arnstein and RI. Artman. unpublished results.G. Alderton, J . Amer. Chem. SOC., 1953, 75, 2391; G. G. F. Newton, E. P.45 N.J. Berridge, G. G. F. Newton, and E. P. Abraham, Biochem. J., 1952, 52, 529.46 R. G. Benedict, W. Dvonch, 0. L. Shotwell, T. G. Pridham, and L. A. Linden-K. Sabaguchi and S. Murao, J . Agric. Chem. SOC. Japan, 1950, 28, 411.Abraham, and N. J. Berridge, Nature, 1953, 171, 606.felser, Antibiotics and Chemotherapy, 1952, 2, 591346 BIOLOGICAL CHEMISTRY.biosynthesis. The configuration of the asymmetric @-carbon atom is notknown; its epimer has been isolated from yeast.47 mesoLanthionine hasalso been isolated from acid hydrolysates of subtilin 48 and may be derivedfrom L-cystine and alanine.Bacitracin, micrococcin P, and bottromycin. The thiazoline ring inbacitracin 49 evidently arises from an N-terminal peptide sequence, iso-leucylcysteine, and further dehydrogenation of such thiazoline derivativescan probably also occur.Thus, two thiazoles have been isolated afteracid hydrolysis of micrococcin P and it has been suggested that they arederived from the peptide sequences, valylcysteine and a-aminobutyryl-cysteine, by conversion into thiazolines and thence into thiazoles: 50Bottromycin has been degraded 51 to a product (VIII) in which the thiazolemay be derived from aspartylcysteine by decarboxylation and dehydro-genation.Ph.CHMe*CH-C0.NH.CH.CH2*C02MeAHAc sAN(V111) uThiolutin, aureothricin, and gliotoxin. The probable relationship ofthiolutin (IX; R = COMe) and aureothicin (IX; R = COEt) to cystine 52suggests that a@-dehydrogenation of cysteine residues can occur. In addition,biosynthesis of these two antibiotics would involve acylation of one cysteineunit and methylation and decarboxylation of the other.The N-methylgroup is probably derived from methionine by transmethylation. 53 Theoccurrence of other extensive metabolic modifications of cysteine is suggestedby the structure of gliotoxin 54 (XI). Biosynthesis of this antibiotic maytake place from the dioxopiperazine (X) of phenylalanine and N-methyl-cystine by appropriate oxidation and condensation reactions. However,according to a recently suggested structure, its biosynthesis may be from47 P. F. Downey and S. Black, J . Biol. Chem., 1957, 228, 171.4 8 G. Alderton and H. L. Fevold, J . Amer. Chena. Soc., 1951, 73, 463.49 I. M. Lockhart, E. P. Abraham, and G.G. F. Newton, Biochern. J . , 1955, 61,634; J. R. Weisiger, W. Hausmann, and L. C. Craig, J . Amer. Chem. Soc., 1955,77,3123.6 o P. Brookes, A. T. Fuller, and J. Walker, J., 1957, 689.51 J. M. Waisvisz, M. G. van der Hoeven, and B. Te Nijenhuis, J . Amer. Chem.52 E. A. Adelberg and M. Rabinowitz, Ann. Rev. Biochem., 1956, 25, 349.53 F. Challenger, Quart. Rev., 1955, 9, 255.54 J. R. Johnson and J. B. Buchanan, J . Amel.. Chem. SOC., 1953, 75, 2103.SOC., 1957, 79, 4524ARNSTEIN THE BIOSYNTHESIS OF PENICILLIN. 347phenylalanine and serine.aa It is noteworthy that aspergillic acid 55 is alsostructurally related to a dioxopiperazine, derived in that case from leucineand isoleucine.Polypeptides.-All the polypeptide antibiotics so far extensivelystudied contain at least one amino-acid with the D-configuration, andD-phenylalanine seems to be particularly widespread (Table 1).In addition,other special structural features are often present.TABLE 1. Occuurrence of D-amino-acids il.t polypeptide antibiotics.D-Amino-acid residuesIA\Antibiotic Asp Glu Leu Phe Dba * aileu 7 Om Ref.......... 56 Actinomycin C, + Bacitracin ............... + + + + 57Gramicidin J ............ + + + 58Gramicidin S ............ + 59Polymixin B, ............ + + 60, 61Tyrocidin A ............ + 62 ............ 63 Tyrocidin B +* Dba = ay-diaminobutyric acid. aileu = allokoleucine.Thus, formation of (' additional " peptide bonds between dibasic and/ordicarboxylic amino-acid residues, as in polymixin B, 61 and bacitracin A,@may result in cyclic products.It has been suggested that biosynthesisof the actinomycins takes place by condensation of two peptides containingan N-terminal 3-hydroxy-4-methylanthranilic acid residue to Z-amino-4 : 6-dimethylphenoxazin-3-one with two identical or different peptide sidechain~.~6 The formation of the many different actinomycins known to existmay thus be due to different combinations of relatively few p r e c ~ r s o r s . ~ ~3-Hydroxyanthranilic acid is presumably derived from t r y p t ~ p h a n , ~ ~5Pa M. R. Bell, J. R. Johnson, B. S. Wildi, and R. B. Woodward, J . Anzer. Chem. SOC.,5 5 G. T. Newbold, W. Sharp, and F. S. Spring, J., 1951, 2679.5 6 A. W. Johnson, Chem. SOC. Special Publ. No. 5, 1956, p. 82.5 7 I. M.Lockhart and E. P. Abraham, Biochem. J., 1956, 62, 645; L. C. Craig,W. Hausmann, and J. R. Weisiger, J . Biol. Chem., 1952, 199, 865.5 8 S. Otani and Y . Saito, Angew. Chem., 1955, 67, 665.5 9 A. R. Battersby and L. C. Craig, J . Amer. Chem. SOC., 1951, 73, 1887; R. L. M.Synge, Biochem. J., 1945, 39, 363.6o W. Hausmann and L. C. Craig, J . Amer. Chem. SOC., 1954, 76, 4892.62 A. Paladini and L. C. Craig, ibid., 1954, 76, 688.63 T. P. King and L. C. Graig, ibid., 1955, 77, 6627.64 W. Hausmann, J. R. Weisiger, and L. C. Craig, ibid., 1955, 77, 723; I. M. Lock-6 5 C. E. Dalgliesh, Adv. Protein Chem., 1955, 10, 31.1958,80, 1001.W. Hausmann, ibid., 1956, 78, 3663.hart and E. P. Abraham, Biochem. J . , 1954, 58, 633348 BIOLOGICAL CHEMISTRY.whilst the methyl group could arise by a carbon-methylation reactionas in the case of mycophenolic acid.66Origin of D-amino-acid residues.The D-configuration could be introducedeither by peptide synthesis from D-amino-acids or by racemization orinversion of configuration after formation of the peptide bond. There isno information about the mechanism by which D-ainino-acid residues areincorporated into the antibiotic polypeptides, but , in the somewhat analogousbiosynthesis of the capsular poly-7-D-glutamic acid by Bacillus subtilis,the preferential utilization of labelled D-glutamic acid could not be demon-strated with intact cells.67 With cell-free preparations, however, glutamyldipeptides were synthesized from either L- or D-glutamine, the highestyield being obtained with a mixture of L-glutamine and D-glutamic acid.68Thus the D-amino-acid residues in antibiotic polypeptides may arise bysynthesis of peptide sequences from both D- and L-amino-acids, followed byhydrolysis of the L-peptide.The D-amino-acids themselves are probablysynthesized by a series of reactions involving alanine racemase and specificD-amino-acid transaminases, which have been found in B. subtilis 69 andB. a n t h r a ~ i s . ~ ~ It may be significant that D-phenylalanine, which appearsto occur frequently in polypeptide antibiotics, has been shown to besynthesized in this way. 70Chloramphenicol (D-threo-2-Dichloroacetamido-l-p-nitrophenylpropane-1 : 3-diol).-Although this antibiotic appears to be related structurally toeither serine or phenylalanine, its mode of biosynthesis is still virtuallyunknown. Production of antibiotic activity by Stre$tomyces venezuelae isstimulated by p-nitrophenylserin01~7~ but this effect is due 72 to formationof N-acetyl-@-nitrophenylserinol, which has some antibacterial activity.Neither p-nitr~[~~C]phenylserinol nor di~hloro[~*C]acetic acid gave rise tolabelled chloramphenicol, although oxidation and acetylation of the addedP-nitrophenylserinol showed that it was metabolized by the organism.72Antibiotics related to Sugars and Amino-sugars.-Stre+tomycin. Onlytraces of isotope were incorporated from 14C-labelled acetate and glycineinto streptomycin (XII) , although both compounds were apparently requiredfor efficient prod~ction.7~ The isotope was located mainly in the guanidinecarbon atoms of the streptidine portion 73 owing to fixation of labelledcarbon dioxide.74 L-Arginine appears to be an intermediate in this reaction,but streptamine is not converted into streptidine by washed mycelial suspen-sions of Streptomyces griseus even when arginine is added.74 Under these con-ditions an unidentified guanidine compoundJ7* possibly y-guanidinobutyric6 6 A.J. Birch, R. J. English, R. A. Massy-Westropp, M. Slaytor, and H. Smith,M. Bovarnick, J . Biol. Chew., 1942, 145, 415; F. Kogl. P. Emmelot, and68 C. B. Thorne, “ Sixth Symp. SOC. Gen. Microbiol.,” Camb. Univ. Press, 1956,6 9 C. B. Thorne, C. G. G6mez, and R. D. Housewright, J . BacterioE., 1955, 69, 357.7 0 C.B. Thorne and D. M. Molnar, ibid., 1955, 70, 420.71 D. Gottlieb, H. E. Carter, M. Legator, and V. Gallicchio, ibid., 1954, 68, 243.if D. Gottlieb, P. W. Robbins, and H. E. Carter, ibid., 1956, 72, 153.J., 1958, 365.D. H. W. Den Boer, Annalen, 1954, 589, 15.p. 68.P. Numerof, M. Gordon, A. Virgona, and E. O’Brien, J . Amer. Chew Soc., 1954,74 G. D. Hunter, M. Herbert, and D. J . D. Hockenhull, Biochem. J., 1954, 58, 249.76, 1341AKNSTEIN : THE BIOSYNTHESIS OF PENICILLIN. 349acid, 75 was formed. Labelled N-methyl-L-glucosamine was incorporatedpreferentially into N-methyl-L-glucosamie of streptomycin, but labelledstreptamine was less efficient than glucose as a precursor of the streptidinemoiety. 76N- Methy l- L-gluc J CHIIIIII ISrreprtdine StreptoseFIG.2. Biosynthesis(XWN-Methyl -L-glucosamineof streptomycin.osamineSince 74-methyl-L-glucosamine was a better precursor than glucose also ofthe streptidine portion, it has been suggested that a series of equilibriumreactions linking derivatives of D-glucose, scyllitol (which is the hexitolcorresponding in structure to streptamine), L-glucose, and N-methyl+glucosamine may account for the biosynthesis of both the streptidine andN-methylglucosamine moieties from either D-glucose or N-methyl-L-glucosamine. ' 5The origin of the streptose moiety remains unknown, but it seemspossible that this sugar (XIV) is synthesized from 6-deoxy-~-sorbo-4-hexulose (XIII) by a rearrangement similar to that occurring in valinebiosynthesis 77 from cc-acetolactate :The occurrence of 6-deoxyhexoses and related sugars in several other anti-biotics produced by Streptomyces, such as magnamycin,78 rhodomycin ,7*erythromycin, and novobiocin, 79 indicates the widespread existence ofnovel pathways of glucose metabolism in these organisms.Kojic acid.The biosynthesis of this weakly active antibiotic, 5-hydroxy-Z-hydroxymethyl-4-pyrone, takes place without cleavage of the carbonchain of glucose,s0 possibly by direct dehydration and oxidation at Co).75 G. D. Hunter, Giorn. Microbiol., 1956, 2, 312.7 6 G. D. Hunter and D. J. D. Hockenhull, Biochem. J., 1955, 59, 268.7 7 M. Strassman, A. J. Thomas, and S. Weinhouse, J . Amer. Chem. SOC., 1956, 77,78 G. 0. Aspinall and J.C. P. Schwarz, Ann. Reports, 1955, 52, 256.70 C. H. Shunk, C. H. Stammer, E. A. Kaczka, E. Walton, C . F. Spencer, A. N.Wilson, J. W. Richter, F. W. Holly, and K. Folkers, J . Amer. Chem. Soc., 1966, 78,1770.1261.H. R. V. Arnstein and R. Rentley, Biochem. J . , 1953, 54, 493; 1956, 62, 403350 BIOLOGICAL CHEMISTRY.Acetate as a Precursor of Antibiotics.-The biosynthesis of aromatic andphenolic compounds by cyclization of poly-p-ketones derived from acetatewas first suggested more than 50 years ago.81 Recent work has indicatedthat acetate may be an important precursor of the tetracyclines and macro-lides, as well as of aromatic antibiotics.Aromatic antibiotics and related compounds. The incorporation of[carbo~y-~~CIacetate into griseofulvin (XV) is compatible with the cyclizationof a polyketone derived from 7 molecules of acetate: 82It is noteworthy that the positions of the oxygen functions correspondexactly to those in the postulated intermediate. The 0-methyl groups arepresumably derived from the methyl group of methionine as in the case ofmycophenolic acid 66 and other methyl ethers.52 The C-methyl group ofmycophenolic acid (XVI) is also derived from methionine 66 by a C-methyl-ation analogous to that involved in the biosynthesis of Ctzs) of ergo~terol.~~Although [carbo~y-~~CIacetic acid gives rise to mycophenolic acid labelledequally in the nucleus and side-chain, mevalonic acid is incorporatedexclusively into ‘the latter.84 The side-chain thus probably arises byoxidation of an intermediate with a C,, side-chain derived from two moleculesof mevalonic acid, whilst the ring structure is synthesized directly fromacetate (Fig. 3).II IMe2C=CH*CH2i CH2*CMe=CH*CH2: - Mevalonic acid?OxidationtI II tt iHO2C-CHZ: CHl.CMe=CH.CH tI 0 f- Me*COZH1+ MeMethionine methyl groupFIG. 3. Utilization of acetate and mevalonic acid for the biosynthesis of mycophenolicacid.Tetracyclines. The acetate hypothesis has been applied in a particularlyelegant way to the problem of the biosynthesis of the tetracycline group.85The carbon atoms which probably originate from the carboxyl carbon atomof acetate are shown in (XVII) by an asterisk and it has been found thatJ. N. Collie, J., 1907, 91, 1806.82 A. J. Birch, R. A. Massy-Westropp, R. W. Rickards, and H. Smith, J., 1958, 360.83 G. J. Alexander and E. Schwenk, J . Anzer. Chem. SOC., 1957, 79, 4554.84 A. J. Birch, R. J. English, R. A. Massy-Westropp ,and H. Smith, J., 1958, 369.85 (Sir) R. Robinson, ‘ I The Structural Relations of Natural Products,” ClarendonPress, Oxford, 1955, p. 58; R. B. Woodward, Angew. Chem., 1956, 68, 13AKNSTEIN : THE BIOSYNTHESIS OF PENICILLIN. 35 1.both [carboxy-14C]- and [met?~yZ-1~C]-acetate are good precursors.86* 87Partial degradation of oxytetracycline derived from [met?ZyZ-l4C]acetateshowed 86 that three degradation products containing C(5) to C(ll), C(6) toand C ~ J + + (11) + (lln) of the ring, respectively, were equally labelled,whereas the N-methyl groups contained less isotope. [a-l4C]Glycinegives rise to chlorotetracycline containing 40% of the total radioactivityin the dimethylamino-group. 87 Since [ca~boxy-~~C]glycine was notsignificantly utilized,87 the a-carbon atom of glycine is used as a one-carbonfragment (? methyl group) for the biosynthesis of the N-methyl groupsand also some other portion of the tetracycline structure. The productionof 6-demethyl analogues of tetracycline and chlorotetracycline by a mutantof Streptomyces aureofaciens 88 suggests that the ‘‘ extra ” methyl group(6x) is introduced at a late stage of tetracycline biosynthesis, possibly by aC-methylation analogous to that in the biosynthesis of mycophenolic acid 66and ergo~terol,~~ and it may be this position which is labelled by [a-14C]glycine.Inhibition of chlorotetracycline biosynthesis either by thiocyanate orby reducing the halide concentration of the medium increases formationof unsubstituted tetracyclines without affecting the total yield of anti-suggesting that halogenation takes place at a late stage, and itseems possible that tetracycline itself may be the substrate.C \CH-!!-HI,CH 0 H CHO c -u-Macrolides. The structure and biogenesis of magnamycin (XVIII)and other macrolides have been discussed by VC’ood~ard,~~ who pointed outthe probable significance of poly-P-keto-acids as intermediates. Theregularity of side-chain methyl groups in erythromycin may be due toparticipation of propionate as a precursor, whereas magnamycin would bederived mainly from acetate. The C(,,)-methyl group of magnamycincould be introduced by replacing one acetate precursor unit by pr~pionate,~*or by transmethylation from methionine (cf. mycophenolic acid 66). The8 6 J. F. Snell, R. L. Wagner, and F. A. Hochstein, Proc. Internat. Conference onthe Peaceful Uses of Atomic Energy, 1956, 12, 431.87 P. A. Miller, J. R. D. McCormick, and A. P. Doerschuk, Science, 1956, 123, 1030.8 8 J. R. D. McCormick, N. 0. Sjolander, U. Hirsh, E. R. Jensen, and A. P. Doers-chuk, J . Amer. Chem. Soc.. 1957, 79, 4561.8B A. P. Doerschuk, J. R. D. McCormick, J. J. Goodman, S. A. Szumski, J . A.Growich, P. A. Miller, B. A. Bitler, E. R. Jensen, M. A. Petty, and A. S. Phelps, ibid.,1956, ‘78, 1508.90 R. B. Woodward, Angew. C h e m , 1957, 69, 50352 BIOLOGICAL CHEMISTRY.metabolic origin of the C(,) aldehyde group of magnamycin is explained ina most ingenious way by a rearrangement of a diol precursor:which would have the same carbon chain as tuberculostearic acid.g0 Asyet, however, there is no direct experimental evidence to support theseelegant hypotheses. H. R. V. A.H. R. V. AKNSTEIN.J. BADDILEY.J. G. BUCHANAN.K. D. GIBSON.W. J. WHELAN.R. T. WILLIAMS

ISSN:0365-6217    

DOI:10.1039/AR9575400306

出版商:RSC    

年代:1957

数据来源: RSC

摘要:

ANALYTICAL CHEMISTRY.IN preparing this Report it has been necessary to break with tradition. Thenumber of analytical papers published in one year is so great that it wouldbe quite impossible to record all the papers or even only the most importantones without this Report’s becoming a mere catalogue. We have thereforetried to concentrate our attention on original papers rather than abstractsand to describe as many new principles as possible in the limited space atour disposal.The papers have been collected and divided into the following sections:1. General.2.3.Conventional Qualitative and Quantitative Inorganic and OrganicAnalysis.Physical Methods of Analysis under the Following General Headings :(a) Electrical methods. (b) Polarography. (c) Chromatography.(d) Absorption spectroscopy.(e) Emission spectroscopy.4. Microchemical Methods.5. Miscellaneous Analysis6. Radio-chemical Methods.7. Apparatus.GENERALGeneral papers of particular interest have dealt with a wide range oftopics. Analytical chemists everywhere are likely to profit from the workof the A.B.C.M./S.A.C. Joint Committee on methods for the analysis oftrade effluents. The four panels dealing with organic matter (general),metallic contaminants, non-metallic contaminants, and physical tests havemade great progress and many agreed methods have been published in theAnalyst in the course of the year. Also on the subject of trade effluentsHapp, Stewart, and Cooper2 have devised a very useful test for the deter-mination of volatile hydrocarbons.In this rather novel method the moistvapour above the sample solution containing the volatile solvent in an air-free system is sampled. This moist vapour is then examined directly inthe mass spectrometer and encouraging results have been obtained in thedetermination of, for example, dichloromethane, aliphatic and aromatichydrocarbons, acetone, and methanol in such waters.Those chemists confronted with problems in thermal analysis will finduseful data in the papers presented at the Symposium 3 on Purity Controlby Thermal Analysis, Amsterdam, 1957.The utilisation of new principles in analysis has been a feature of the1 Analyst, 1957, 82.2 G. P. Happ, D. W. Stewart, and H. C . Cooper, Analyt. Chem., 1957, 29, 68.3 Analyt.Chim. Acta, 1957, 17, 1-174.REP.-VOL. LIV 354 ANALYTICAL CHEMISTRY.year. A method of analysis based on observation and measurement ofthe phosphorescent light emitted by appropriately excited molecules hasbeen developed.* The method appears applicable to multiple-bond organicmolecules, each of which exhibits a unique phosphorescence which may becharacterised even in mixtures. For quantitative work very carefullystandardised conditions have to be used. Reflectance measurements havebeen utilised by Rose for the determination of mean particle size of fineblack powders, e.g., carbon black, graphite, etc. A simple reflectometerhead is used and the method is calibrated in terms of powders of knownparticle size. A useful feature of the method is that in the case of pelletsor aggregates, it is the reflectivity of the particle forming the aggregatesand not the aggregate itself that is measured and hence the mean particlesize of the unit particles in an aggregate can be obtained.for the determination of metals in solution.The metal under considerationmust be reactive towards a reagent which is optically active. The opticalrotation of the reagent solution is measured and the solution of the metalion is added to an excess of this reagent solution. Any precipitate is filteredoff and the optical rotation of the filtrate again measured. . Since understandard conditions the optical rotation of a solution is proportional to theconcentration of active ingredient present, the concentration of metal canbe calculated from the change in rotation produced.Silver and iron havebeen thus determined by reaction with D-tartaric acid.Logie 7 has worked out a new method of concentration or removal ofinterfering ions from those being determined. The principle of separationis the electrolysis of the solution in a two-compartment cell separated byan ion-exchange membrane. A cation-exchange membrane being used,the metal ions in the anode compartment pass irreversibly through themembrane into the cathode compartment, leaving the trace element beingstudied, if it is an anion, in the anode compartment. The use of an anion-exchange membrane has of course the opposite effect and use. This methodhas been used with success in the determination of traces of boron in metallicsodium. The sodium is removed by electrolysis of the hydroxide solutionusing a cation-exchange membrane, before isolation of the boron from theanode compartment of the cell and photometric determination of the boronwith curcumin.Analysts requiring a regular supply of diazonium cations for the deter-mination of phenols, etc., or for other purposes may find the proceduredescribed by Lambert and Cates for the storage of such cations dispersedand dried on nuclear sulphonic acid ion-exchange resin of great use.Whenrequired, the cation is released by treatment of the resin with an inert saltsuch as potassium chloride, the pH of the solution adjusted as required, andany coupling reaction carried out. The method of preparation of testpapers with diazonium ions fixed as stable zirconium ions is also described.4 R.J. Keirs, R. D. Britt, jun., and W. E. Wentworth, Analyt. Chem., 1957,29,202.5 H. E. Rose, J. Appl. Chem., 1957, 7, 244.M. Freegarde, Chem. and Ind., 1957, 984.7 D. Logie, Chem. and Ind., 1957, 225.8 J . L. Lambert and V. E. Cates, Analyt. Chem., 1957, 29, 508.A new principle of differential polarimetry has been used by FreegardHASLAM AND SQUIRRELL. 355QUALITATIVE AND QUANTITATIVE INORGANIC AND ORGANIC ANALYSISThe subjects dealt with under this heading tend to be on conventionallines. It should be emphasised, however, that in the inorganic field at anyrate great stress is being laid on complexometric titrations. There arevery few metals indeed which cannot be determined by some form ofcomplexometric procedure.Qualitative.-A procedure for the separation of metals into groups and amore comprehensive scheme of qualitative analysis has been set out bySalaria,g based on the principle of formation and decomposition of thio-salts, This scheme extends that already described by the same author toinclude rhodium, ruthenium, osmium, palladium, iridium, gallium, indium ,rhenium, tantalum, niobium, germanium, scandium, and the rare earthsand alkali metals.Also on the subject of group separation, two authors lo have put forwarda new and very comprehensive scheme of qualitative analysis of anions.The basis of the systematic procedure is the precipitation of difficultlysoluble salts of anions into groups by basic group reagents in sodiumcarbonate solution.Each group precipitate or filtrate is then examinedfor the individual anions in the group.The separation of niobium and tantalum has been achieved by a sublim-ation method.11 The metals as their oxides are caused to react withaluminium chloride, bromide, or iodide and the niobium and tantalumhalides formed are separated by fractional sublimation at controlled tem-perature.A simple and rapid test for arsenic, likely to prove of value in the detectionof arsenic in many organic and inorganic substances, has been devised byClark.12 The solution of the test substance is first reduced with stannouschloride, after which zinc dithiol is added. In the presence of arsenic awhite turbidity is produced in the boiling solution.The principle of thetest may be extended to the detection of germanium. The test solution isboiled with hydrochloric acid and potassium chlorate. The zinc dithioltest is carried out on a sample of the vapour arising from the solution.A delicate test for elementary sulphur13 involves the reaction of abenzene solution of the material with a pyridine solution of lead thiophen-oxide. The lead thiophenoxide polysulphide produced is gradually con-verted, at room temperature, into black lead sulphide.Trace amounts of iron in extreme dilution (1 part in 5 x lo8 in water)and in solutions obtained from alloys containing large amounts of copper,cobalt, nickel, and zinc may be detected by using a reagent containing2 : 2'-dipyridyl or 1 : 10-phenanthroline in thioglycollic acid.l* The com-bined reaction of the mixed reagents avoids preliminary reduction ofthe iron and lengthy separations from traces of other elements.WhereThe products obtained are quite pure.9 G. B. S. Salaria, Analyt. Chim. Acta, 1957, 16, 509.10 I. K. Taimni and L. Manohar, ibzd., 1957, 17, 367.11 M. Chaigneau, Compt. rend, 1957, 244, 900.1 2 R. E. D. Clark, Analyst, 1957, 82, 760.13 H. Krebs, H. Fassbender, and F. Jorgens, 2. analyt. Chem., 1957, 155, 250.14 F. Feigl and A. Caldas, Analyt. Chem., 1957, 29, 680356 ANALYTICAL CHEMISTRY.the iron has to be concentrated or separated a procedure recommendingprecipitation as hydroxide in the presence of an alumina collector isdescribed.In the organic field a very comprehensive scheme for the semimicro-qualitative identification of 21 types of anionic surface-active agent hasbeen presented by Holness and Stone.15 Methods have been worked outfor the isolation of the active agent from the commercial prepxation.One of the features of the method is the use of a mixture of two dyes,Disulphine blue V200 and Dirnidium bromide, which, when used at twodifferent pH values, give coloured chloroform extracts in accordance withthe type of surface-active agent present.Two new spot tests for nitromethane have been described by Feigl andGoldstein.16 The first is based on Nef degradation to yield formaldehydewhich is detected by means of chromotropic acid in concentrated sulphuricacid, and the test can also be used for nitroethane, which yields acetaldehydedetectable by the sodium nitroprusside-piperidine reaction, The secondtest takes advantage of the blue colour formed by nitromethane with 1 : 2-naphthaquinone and calcium oxide.Since nitromethane can be producedfrom monochloroacetic acid, dimethyl sulphate, iodomet bane , and methylhydrogen sulphate, the same reaction can also be used with little modificationas a spot test for these compounds.The reaction of rhodanine with 1 : 2-naphthaquinone-4-sulphonic acidto give a highly coloured product is the basis of Feigl and Gentil’s spottests for monmhloro(or bromo)acetic acid, alkali thiocyanates, thiourea andits derivatives, and cyanamide and its salts.17 All these compounds areconverted into rhodanine before application of the test by the Nenckisynthesis.The oxidative fission of organic substances by fusion with benzoylperoxide and identification of the characteristic gaseous products of cleavagehas been found to be a particular advantage in identification work.18O-Methyl and N-methyl compounds yield formaldehyde, N-ethyl and-propenyl compounds yield acetaldehyde, whilst sliphatic oximes andaliphatic and aromatic hydroxamic acids yield nitrous acid.Quantitative (Gravimetric) .-There have been several interesting develop-ments in gravimetric analysis.Oxygen in titanium and particularly in titanium alloys containingmanganese has been determined by a method due t o ElweU and Peake 19involving chlorination of the sample in the presence of excess of carbon,argon being used as purge gas.The oxygen is converted into carbonmonoxide which is purified, then oxidised to carbon dioxide by passageover heated wpper oxide, and finally weighed.Salicylaldoxime is often used as a reagent for copper. The reactions ofo-hydroxyacetophenone oxime, which may be regarded as the methylderivative of salicylaldoxime, with various metals have been compared with1 5 H. Holness and W. R. Stone, Analyst, 1957,82. 166.16 F. Feigl and D. Goldstein, Analyt. Chcwz., 1957, %I, 1521, 1522.17 F. Feigl and V. Gentil, ibid., p. 1715.1 8 F. Feigl and E. Silva, Analyst, 1957, 02, 582.1@ W. T. Elwell and D. M. Peake, ibid., p. 734HASLAM AND SQUIRRELL. 357those of salicylaldoxime.2* As a result of these investigations, it is suggestedthat the new reagent may find useful application in the gravimetric deter-mination of copper, nickel, palladium, vanadium, and titanium, as well asfor the colorimetric determination of iron, uranium, and vanadium.o-Hydroxyacetophenone oxime has been shown by Poddar21 to haveseveral advantages over salicylaldoxime for the precipitation of copper atpH 2-3 and nickel at pH 5-55.The precipitates possess greater stabilityand are easier to purify. With this new reagent nickel and copper may beseparated from one another and from a large number of other metals.The behaviour of metal diethyldithiocarbamate complexes in chloroformsolution on shaking with solutions of other metallic salts of known pH valuehas led to the preparation of a " displacement series." 22 For example,mercury solutions will displace copper from the chloroform solution of thecopper complex and so on.The use of this principle may lead to interestingdevelopments in the field of metallurgical analysis.Silverman and Trego 23 have devised a method for the separation anddetermination of barium in zirconyl chloride or zirconium metal, basedon a double precipitation of the zirconium as zirconyl chloride from ahydrochloric acid medium followed by a cupferron precipitation-chloroformextraction of any remaining zirconium. The barium is then determinedgravime trically as the sulphat e.of the reductionof quadrivalent and sexavalent selenium solutions to the element by meansof sulphur dioxide in heated but closed flasks.As a result of this work ithas been shown that it is possible to determine quadrivalent and sexavalentselenium in the presence of one another by preliminary reduction of theSeIV to element in weak hydrochloric acid solution followed by filtrationand subsequent reduction of the Sen in the filtrate under more stronglyacid conditions.The difficulties in the determination of molybdenum in titanium byprecipitation as sulphide, such as hydrolysis of the titanium, the need of arapid hydrogen sulphide stream, and the need of a lengthy digestion timebefore the molybdenum sulphide is filterable, have been largely overcomeby the use of thioacetamide; 25 this is added to an appropriately treatedacid solution of the sample, and the solution kept at the temperature ofboiling water for 1 hour.The precipitated molybdenum sulphide in thecooled solution is dense and easily filterable and after combustion is weighedas molybdenum trioxide.The gravimetric determination of beryllium, after separation from iron ,aluminium, and titanium, has been described by Nadkarni, Varde, andAthavale.26 The separation is effected by adsorption of the beryllium onan 1Ft.A-120 ion-exchange resin after complexing the iron and aluminiumA thorough study has been made by Bode and Stemmer20 S. N. Poddar, 2. analyt. Chem., 1967, 154, 254.21 Idem, ibid., 1957, 155, 327.22 G. Eckert, ibid., p. 23.23 L. Silverman and K. Trego, Analyt. Chim. Acta, 1957, 17, 280.24 H. Bode and H.D. Stemmer, 2. anaZyt. Chem., 1967, 155, 96.as W. N. McNerney and W. F. Wagner, Analyt. Chem., 1957, 29, 1177.26 M. N. Nadkarni, M. S. Varde, and V. T. Athavale, Analyt. Chim. Acta, 1967,16,421358 ANALYTICAL CHEMISTRY.with EDTA and the titanium with hydrogen peroxide. The adsorbedberyllium is eluted from the column with hydrochloric acid and determinedby ignition to BeO, after a double precipitation as hydroxide. The method isof particular use in the analysis of beryl.Boron has been determined by a rapid gravimetric procedure whichinvolves conversion into tetrafluoroboric acid and precipitation of thiswith an organic reagent-nitron. The advantages of the method 27 are thatdistillation is unnecessary and fluoride and weak acids and bases do notinterfere.Methods are given to avoid interferences due to bromide,hydriodic acid, nitrous acid, chromic acid, etc.Quantitative (Volumetric) .-In the field of conventional volumetricanalysis further work has been carried out on practical working standards.Some experiments of Easterbrook 28 indicate that working standard sodiumcarbonate is best prepared as follows: Sodium hydrogen carbonate of highquality is first purified, then converted into sodium sesquicarbonate. Thelatter, on heating at 270°, yields sodium carbonate of first-class purity andof high stability at that temperature.Again on the subject of standardisation, Runge et aZ.29 have indicatedthat diaryldisulphimides, (R=SO,) ,NH, in particular 3 : 3’-dinitrodiphenyl-disulphimide, appear to be useful substances for the standardisation ofalkalis by titrimetric procedures.The behaviour of FeIII 1 : 2-dihydroxybenzene-3 : 5-disulphonic acidcomplex to changes in pH has been studied by Sen, Berg, and West30 andshown to be reversible and reproducible.It is useful as a reversible anduniversal indicator in pH titrations, giving colours ranging from light greenat pH 2 through violet to deep orange at pH 13.In the determination of alkali hydroxide in the presence of alkalicarbonate Szekeres and BakB~s-PolgAr,~~ after precipitation of the carbonateas barium carbonate, prefer to titrate the hydroxide with standard zincchloride rather than standard acid, with phenolphthalein as indicator.Phosphorus in many organic compounds, both fluorinated and un-fluorinated, may readily be determined on the semimicro-scale after fusionwith sodium peroxide in a bomb.32 The phosphate in the reaction productsis precipitated as quinoline molybdophosphate before titration.In a method by Pietsch 33 phenarsazinic acid is used for the quantitativeprecipitation of quinquevalent vanadium at pH 2.The precipitate isdissolved in alkali, and the vanadium reduced with oxalate before filtrationfrom phenarsazinic acid. After oxidation with permanganate, the vanadiumis determined by titration with standard ferrous solution. Good resultsare obtained in the presence of magnesium, nickel, zinc, and chromate.Tin in titanium alloys may be detennined, after preliminary solution ofthe sample, by reduction of the tin with hypophosphite in 1 : 1 hydrochloric27 C.A. Lucchesi and D. D. DeFord, Analyt. Chem, 1957, 29, 1169.28 W. C. Easterbrook, Analyst, 1957, 82, 383.29 F. Runge, J. Behrends, and A. Ernst, 2. analyt. Chem., 1957, 158, 266.8 0 B. Sen, E. W. Berg, and P. W. West, Analyt. Chim. Acta, 1957, 17, 355.81 L. Szekeres and E. BakAcs-PolgAr, 2. analyt. Chenz., 1957, 156, 194.32 T. R. F. W. Fennell, M. W. Roberts, and J . R. Webb, Analyst, 1957, 82, 639.33 R. Pietsch, 2. analyt. Chem., 1957, 155, 189HASLAM AND SQUIRRELL. 35 9acid.34 The stannous chloride produced is titrated with iodate-iodidesolution, starch being used as indicator.A method of ferrometric determination of silver, which is particularlysuitable for the examination of silver-copper alloys, is described by Erdeyand Vigh35 and is based on direct titration of the silver solution, in thepresence of acetate buffer and sodium fluoride. The ionised silver is reducedto metal, and Variamine-blue is used as end-point indicator.Barltrop and Morgan36 have presented a new method for the deter-mination of water and alcohols based on titration with acetic anhydridein the presence of perchloric acid, using the ferric hydroxamate colourreaction as a means of external end-point detection.At the end-pointthe red colour of ferric acethydroxamate is formed. The method can beused for the estimation of water in acetic acid, acetonitrile, ethyl acetate,acetone, benzene, and carbon tetrachloride and is said to be both rapid andaccurate.Uranium has been determined in alloy systems37 by precipitation asuranyl ammonium phosphate from a solution of the sample containing anacetate buffer and sufficient EDTA to complex interfering elements.Theacid solution of the separated uranium is passed through a lead reductorand the quadrivalent uranium solution so formed is titrated with standardceric sulphate solution.The interest in, and use of, complexones has been world-wide and this isdemonstrated by the vast amount of publication this subject has receivedthroughout the year. New complexones have been introduced, newindicators used, and many new procedures described. Of the many paperspublished we can review but a few.A new selective complexone for the direct titration of calcium in thepresence of magnesium has been developed and is described by Schmid andR e i l l e ~ .~ ~ This complexone, ethylene glycol bis-(2-aminoethyl ether)-NNN'N'-tetra-acetic acid, gives a good potentiometric end-point with amercury indicator electrode. The total magnesium and calcium is found bydirect titration with EDTA, and the magnesium found by difference.In the titration of complexing agents both in presence and in absence ofindicator, consideration has been given by Flaschka and Soliman 39 to theminimum differences between the stability constants of complexes whichwill permit one metal to be titrated in the presence of another. Moreover,particular consideration has been given to the advantages of triethylene-tetramine as a reagent for this type of titration.The dye Fast-grey FL4 4o has proved a useful indicator in complexometrictitrations using EDTA.In conjunction with other indicators, e.g., Erio-chrome-black T, it can be used for the direct determination of thorium,ferric iron, bismuth, and zinc, or the analysis of binary mixtures. Thorium,34 H. J. G. Challisand J. T. Jones, AnaZyst, 1957, 82, 658.35 L. Erdey and K. Vigh, 2. analyt. Chem., 1957, 157, 184.36 J . A. Barltrop and K. J. Morgan, Analyt. Chim. Acta, 1957, 16, 520.37 G. W. C. Milner and J. W. Edwards, ibid., p. 109.3* R. W. Schmid and C. N. Reilley. Analyt. Chem., 1957, 29, 264.99 H. Flaschka and A. Soliman, Z . analyt. Chem.. 1967, 158, 254.40 H. Khalifa, Analyt. Chim. Ada, 1957, 17, 194360 ANALYTICAL CHEMISTRY.ferric iron, and zinc can also be determined in the presence of many otheranions and cations.A new indicator Calcon (C.I.202), described by Hildebrand and Reilley,41allows the direct titration of calcium in the presence of magnesium withEDTA. The titration is carried out at a pH of 12-13 after initial precipit-ation of the magnesium with diethylamine; the sharp end-point colourchange is from pink to blue.A method first developed by Schwarzenbach in which account is takenof the acid liberated as a result of the interaction of certain bivalent metals,such as copper and zinc, with the disodium salt of ethylenediaminetetra-acetic acid has been shown to be unsatisfactory. An alternative form oftitration is proposed42 in which the bivalent metal is titrated with astandardised solution of the disodium salt of ethylenediaminetetra-aceticacid until further addition of titrant no longer produces a change in thepH of the solution.EDTA has been used by Ueno for the simultaneous complexometricdetermination of mercury and copper.The total metals itre titrated bythe addition of excess of complexone and back-titration with standardcopper solution at pH 10. Potassium iodide is then added which decom-poses the mercury-EDTA complex, liberating an equivalent of EDTA,which is again titrated back with more standard copper solution.The complexometric titration of calcium with EDTA has been achievedby Ramaiah and Vishnu using a photometric end-point with the copper-ammonium complex as an indicator.Copper sulphate solution is added tothe calcium solution under test and the combined solution made greaterthan 1 . 5 ~ with respect to ammonia. The absorption at 630 mp is measuredafter each addition of EDTA, and a sharp fall in absorbance is noticed whenall the calcium has been titrated and the EDTA complex with copper startsto form, causing a decrease in the concentration of coloured cuprammoniumions.Iron, aluminium, and chromium may be determined in the presence ofeach other 45 by procedures based on the different stabilities of their com-plexes with EDTA. Iron is determined by adding excess of EDTA at pH1-5 then warming to 50-60" and back-titrating the excess of EDTApotentiometrically with standard iron solution. Iron and chromium aredetermined by a similar titration after preliminary buffering to pH 5, addi-tion of excess of EDTA, boiling and back-titrating at 50-60" at pH 1.5.Iron, aluminium, and chromium are determined by buffering to pH 5.0then adding excess of EDTA and boiling before back-titration at pH 5.0and 40".Weiner and Ney 46 have shown that the determination of small amountsof chromic ion in the presence of excess of chromate can be accomplished bycomplexing with excess of EDTA at the boiling point; the excess of EDTA41 G.P. Hildebrand and C. N, Reilley, Analyt. Chem., 1957, 29, 258.42 J. Haslam, D. C. M. Squirrell, and M. Heskins, Analyst, 1957, 82, 117.43 K. Ueno, Analyt. Chem., 1957, 29, 1668.44 N. A. Ramaiah and Vishnu, Analyl. Chim.Acta, 1957, 16, 569.45 R. Patzak and G. Doppler, 2. auaalyt. Chem., 1957, 156, 248.46 R. TVeiner and E. Ney, ibid., 1957, 157, 105HASLAM AND SQUIRRELL. 361is then back-titrated, in the presence of buffer, with standard nickel solution,murexide being used as indicator.Indirect use of complexone has been made in several ways, for instance,indirect complexometric methods have been proposed by Sen4' for thedetermination of sodium and potassium. The sodium is precipitated assodium zinc uranyl acetate and the zinc in a solution of the precipitatecontaining ammonia, ammonium chloride and carbonate, is titrated withEDTA using Eriochrome-black T as indicator. Potassium is precipitatedas potassium sodium cobaltinitrite, and the cobalt converted into thiocyanatein the presence of acetone, then titrated with EDTA to absence of bluecolour.The lamp method for the determination of total sulphur in petroleumproducts has been improved.48 The sample is aspirated into an oxy-hydrogen flame and the products of the combustion are absorbed in hydrogenperoxide. The sulphate so formed is then determined by the addition ofexcess of barium acetate, the excess of which is then determined by a back-titration with EDTA.Tantalum, niobium, and titanium can be separated from other coii-stituents of hard metals such as tungsten, iron, and cobalt by precipitationwith ammonia in the presence of glycerol and EDTA as described by Lassnerand W eisser.49The number of papers on organic analysis which can be classified underconventional volumetric analysis is obviously smaller than that on inorganicanalysis.Two useful methods have been described, however, by Fickenand Lane 59 for the titration of the basic functional groups in ion-exchangeresins, perchloric acid being used in glacial acetic acid media. The firstmethod, although time-consuming, appears more reliable and is based onthe direct slow titration of the base in the resin at 100" to an Oracet-blue Bor Crystal-violet indicator. The second, more rapid method, which tendsto give low results, is based on treatment of the resin with excess of perchloricacid in acetic acid solution at loo", followed by filtration and back-titrationof the excess of perchloric acid with sodium acetate in glacial acetic acidsolution.Smith 51 has developed two new titrimetric methods for the quantitativeanalysis of aryloxysilanes.In the first, a bromide-bromate titration iscarried out in glacial acetic acid media, and in the second, the titrant ispotassium methoxide in anhydrous ethylenediamine, o-nitroaniline beingthe indicator. The first method also appears applicable to phenyl ortho-esters of carboxylic acids.Vicinal glycols such as batyl alcohol and cyclohexane-1 : 2-diol may bereadily determined by reaction of the glycol with trimethylammoniumperiodate in a mixed solvent containing ethyl alcohol, ethyl acetate, andacetic acid.524 7 B. Sen, 2. analyt. Chem., 1957, 157. 2.48 0. N. Hinsvark and F. J. O'Hara, Analyt. Chem., 1957, 29, 1318.49 E. Lassner and H.Weisser, 2. analyt. Chem., 1957, 15'7, 343.6 0 G. E. Ficken and E. S. Lane, Analyt. Claim. Acta, 1957, 16, 207.61 B. Smith, Acta Chem. Scand., 1957, 11, 558.b2 R. J. B. Reddaway, Analyst, 1957, 82, 506362 ANALYTICAL CHEMISTRY.PHYICAL METHODSElectrical.-It is apparent from the amount of literature on electro-chemical methods that new potentiometric tests as well as coulometric andhigh-frequency titrations are finding increasing use. Amongst the moreimportant introductions is the method of potentiometric titration in non-aqueous media, by means of alkylammonium hydroxide.53In the field of inorganic electrochemical analysis a method of internalelectrolysis has been developed by Kangro and Pieper st for the precisedetermination of iron.The iron solution with the iron present as ferricchloride is subjected to internal electrolysis with a platinum cathode and asilver anode. The test is carried out in the presence of hydrochloric acidand potassium iodide and in an atmosphere of carbon dioxide. The ter-valent halide is reduced to bivalent halide at the cathode, the third halogenatom being subsequently deposited as silver halide on the anode; theproportion of silver halide is determined by difference. A study has beenmade of the possibility of extension of the principle of the test to the deter-mination of oxidising and reducing agents.Erdey and Siposs 55 have described a method in which copper may bedetermined by direct reductometric titration with ascorbic acid in thepresence of ammonium chloride and sodium acetate.The end-point may bedetermined either visually or potentiometrically and suffers little interferencefrom other ions.A method previously employed with a polarographic finish has beenmodified to determine large proportions of zinc in minerals and foundryproducts.56 The material, with or without additives such as iron or carbon,is heated at 1100" in a stream of hydrogen. The zinc in the solution of thesublimate, with any lead present precipitated as sulphate, is titrated potentio-metrically with standard potassium ferrocyanide solution.A novel method has been developed by Schmidt 57 for the determinationof potassium in potassium salts. The potassium is precipitated with excessof sodium tetraphenylboron, the mixture bulked to volume and filtered, andan aliquot part of the filtrate back-titrated with standard thallous solution,a modified dead-stop end-point being used.The principle of the testmay be extended to the examination of ammonium salts and the salts ofcertain organic bases.On the subject of coulometry, it has been shown by Lingane et aZ.58that the current efficiency in the electro-generation of ceric ion is a functionof current density, falling below 100% at very high and very low densities.Iodide may, however, be accurately titrated to iodine at low currentefficiences owing to direct oxidation of the iodide to iodate a t the anode,at a potential slightly in advance of the cerous-ceric oxidation potential.The iodate so formed in turn oxidises the iodide to iodine. In fact, verylittle of the total current used results in the formation of ceric ion.The53 J. S. Fritz and S. S. Yamamura, Analyt. Chem., 1957, 29. 1079.54 W. Kangro and H. Pieper, 2. analyt. Chem., 1957,155, 169.55 L. Erdey and G. Siposs, ibid., 157, 166.66 W. Geilmann, R. Neeb, and H. Eschnauer, ibid., 154, 418.57 H. J . Schmidt, ibid., 157, 321.5 8 J. J . Lingane, C. H. Langford, and F. C. Anson, Analyl. Chim. Acta, 1957, IS, 166HASLAM AND SQUIRRELL. 363titration of iodide can be satisfactorily carried out, without the presenceof cerous ion at all, at suitable current densities.The use of coulometry has been further extended by Carson et aZ.59to the determination of plutonium. The plutonium is first oxidised to avalency of 6, then, by using electrically generated ferrous ion, titratedback to plutonium(1v).The method, which can be used for samples con-taining 3 y to 10 mg. of plutonium, is subject to very few interferences.In volumetric methods for the chemical determination of sulphur inorganic compounds containing nitrogen, difficulties have often arisen inthe titration because of the presence of nitric and nitrous acids in the Preglcombustion products. Massie 60 has overcome these difficulties by neutralis-ation of the combustion products with ammonium hydroxide and additionof ethanol before conductometric titration of the sulphate with bariumacetate solution.In high-frequency work, one of the disadvantages of most titrimetersis that they only work satisfactorily at comparatively low electrolyteconcentrations, An instrument has been designed by Lane whichoperates at 250 Mc./sec.and enables tests to be carried out a t electrolyteconcentrations up to O-7~-sodium chloride or its equivalent. The newapparatus is particularly suitable for titrations of acids and bases in non-aqueous media.The detection of end-points in high-frequency conductometric titrationsinvolving colloidal electrolytes has been facilitated by Kupka and Slabaugh ,62who have described an instrument operating at a fixed frequency andincorporating an amplitude-stabilised oscillator worked in conjunction witha specially shaped conductance cell. By using this instrument, titrations incolloidal systems can be carried out rapidly even if the conductance changeat the end-point is only a fraction of the total conductance of the solution.Square-wave titrimetry has been successfully employed in titrationsinvolving redox, precipitation , and complex-forming reactions.In themethod by Laitinen and Hall 63 a square-wave alternating signal of constantcurrent or voltage is applied to a pair of micro-electrodes and the currentor voltage output from these electrodes during the titration is measured.By using the procedure, a differential titration curve of equimolar mixturesof chloride, bromide, and iodide can be carried out.In the organic and inorganic field, automatic titrimeters are being usedto an increasing extent in analytical laboratories. In a general paperHaslam and Squirrella describe their use in connection with the deter-mination of: (a) Nitrogen and chlorine in polymers ; (b) iron and aluminium ;(c) water in organic compounds; (a) formaldehyde by the neutral sulphitemethod; (e) Nylon 610 salt in the moist material; (f) aldehydes and ketonesin methyl methacrylate monomer; and (g) the detection of “ Terylene.”59 W.N. Carson, jun., J. W. Vanderwater, and H. S. Gile, Analyt. Chem., 1957,6 0 W. H. S. Massie, Analyst, 1957, 82, 352.61 E. S . Lane, ibid., p. 406.62 F. Kupka and W. H. Slabaugh, Analyt. Chem., 1957, 29, 845.63 H. A. Laitinen and L. C. Hall, ibzd., p. 1390.64 J . Haslam and D. C. M. Squirrell, Analyst, 1957, 82, 511.29, 1417364 ANALYTICAL CHEMISTRY.The direct titration of organic functional groups has been carried outby Jucker 65 using chromium(r1) sulphate.The substance is dissolved in asuitable solvent, e.g., water, dimethylformamide, pyridine, etc., and thesolution brought to an appropriate pH with sulphuric acid. The titrationis carried out potentiometrically using a platinum indicating electrode anda bridged calomel cell as reference. Azo-, nitro-, nitroso-, and quinonoidgroups give sharply defined titration curves and in several cases whereisomers have different redox potentials, with consequent different steps inthe titration curve, they can be determined without separation.Analysts faced with problems involving potentiometric titrations innon-aqueous media will find useful information in a paper by van der Heijdeand Dahmen 66 which describes the practical criteria in the choice of suitablesolvents and conditions.The acidity potential ranges of twelve solventsare given, together with the half-neutralisation of sixteen acids in them.Tetra-alkylammonium bases dissolved in pure pyridine are described asnew titrants for acids in non-aqueous media.The use made by Fritz 53 of tetra-alkylammonium hydroxide in benzene-methanol as a titrant for phenols and organic acids in acetone media hasbeen mentioned previously. The method utilises a glass, modified calomelelectrode system, and under certain conditions a differential titration ispossible. Fritz, Moye, and Richard 67 have extended the use of this titrantto the titration of nitro-aromatic amines and polynitro-aromatic com-pounds a , ~ weak acids, in pyridine solution.A useful application of coulometry to organic analysis has been describedby Miller and DeFord 68 in a method for the spectrophotometric titrationof olefins with electrically generated bromine.The bromine is generatedin an acetic acid-methanol medium from potassium bromide with mercuricchloride present as catalyst for direct titration. The titration vessel isalso a photometric cell, and the progress of the titration can thus be followedspectrophotometrically and a plot made of absorbance against time atconstant current, at a specific wavelength. The stoicheiometric end-pointis determined by finding the point of intersection of the two straightportions of the plot before and after the end-point.Po1arography.-Advances in polarographic and amperometric methodscontinue to be made.A polarographic method for the determination ofgermanium in samples containing from 0.001 to 10% of germanium has beendeveloped by Sauvenier and D~yckaerts.~~ The procedure is based onextraction of the germanium as GeC1, by carbon tetrachloride underappropriate conditions, followed by polarographic estimation of the Ge( IV)in the extract, after re-extraction into a boric acid-KC1 base solution atpH 8.9.Reynolds 7O has described how tin stabiliser, added as sodium stannateto hydrogen peroxide, may be determined by passage of the dilute sulphuric85 H. Jucker, Analyt. Ghim. Acta, 1957, 16, 210.66 H. B. van der Heijde and E.A. M. F. Dahmen, ibid., p. 378.6 7 J. S. Fritz, A. J. Moye, and M. J. Richard, Analyt. Chem., 1957, 29, 1685.68 J. W. Miller and D. D. DeFord, ibid., p. 475.6s G. H. Sauvenier and G. Duyckaerts, Analyt. Chim. Acta, 1957, 16, 692,70 G. F. Reynolds, AnaZyst, 1957, 82, 46HASLAM AND SQUIRBELL. 365acid solution of the peroxide through a cation-exchange resin in the hydrogenform. The tin retained on the resin is eluted with hydrochloric acid fromwhich any traces of hydrogen peroxide are removed by boiling beforepolarographic determination of the tin.A polarographic method of determination of lead has previously beenworked out based on the fact that thorium will displace lead from lead“ complexonate ” solution and the displaced lead may then be determinedpolarographically. It has now been shown by Flaschka and Barakat 71 thatthe principle can be extended to the corresponding amperometric titrationof the thorium.The amperometric titration of microgram and sub-microgram quantitiesof fluoride has been carried out by Johanne~son.’~ The method uses arotating aluminium electrode and a stationary platinum electrode; aconventional current-titre curve is obtained by using N/100-thorium nitratesolution when the titration is carried out in the presence of perchloricacid.On the organic side, antioxidants, e.g., NN‘-di-sec.-butyl-p-phenylene-diamine and $-n-butylaminophenol, have been determined in petrol by apolarographic method due to Gaylor, Conrad, and Landerl 73 using a wax-impregnated graphite electrode, with a solvent-electrolyte of lithiumchloride in propan-2-01.The wax impregnation of the solid electrodereduces residual current and increases sensitivity at lower concentrations.This electrode may find other uses, as it can be used in both aqueous andnon-aqueous media and for both oxidation and reduction reactions.Chromatography.-Although interest in paper and column chromato-graphy is being maintained, the most significant change throughout the yearhas been the increased attention paid to gas-liquid chromatography.Applications of this method of test are being made in most organic analyticallaboratories in this country. It is also probable that high-voltage electro-phoresis, as practised by will prove to be a very useful method ofphysical separation in analysis.A very comprehensive paper by Pfrengle 75 on the paper chromatographyof condensed phosphates such as penta- and hexa-phosphates describestheir separation by appropriate elution on paper and subsequent identific-ation by application of a molybdenum-blue test.The process may be madequantitative by cutting out the paper zones containing the particularpolyphosphates ; these are then hydrolysed to orthophosphate with acidbefore final determination by the molybdenum-blue test.Blasius and Czekay 76 have made a very detailed study of the paper-chromatographic and electrophoretic separation of molybdates and tung-states, of niobium and tantalum as their oxalate complexes, and further,of silicates and phosphates.A very sensitive paper-chromatographic test for the detection andH.Flaschka and M. F. Barakat, 2. analyt. Chem., 1957, 156, 321.72 J . K. Johannesson, Chem. and Ind., 1957, 480.73 V. F. Gaylor, A. L. Conrad, and J. H. Landerl, Analyt. Chem., 1957, 89, 224.74 D. Gross, Nature, 1957, 180, 596.75 0. Pfrengle, 2. analyt. Chem., 1957, 158, 81.76 E. Blasius and A. Czekay, ibid., 1957, UQ, 81366 ANALYTICAL CHEMISTRY.determination of microgram amounts of fluorides by Hall 77 is one inwhich the fluoride solution is added to calcium chloride-thorium nitrateimpregnated paper. A precipitate of calcium fluoride is produced on thestarting line and this precipitated calcium fluoride adsorbs the thoriumsolution very strongly. Interfering impurities in the solution under testare now removed by elution with an acetone-acetic acid solution.Thecalcium fluoride with adsorbed thorium is detected by staining withSolochrome-brilliant-blue BS.Oxycellulose has been found by Elvidge et ~ 1 . ~ 8 to be a very usefulcation-exchange medium in the determination of bacteriostatic agentssuch as phenol and chlorocresol and active ingredients such as atropinesulphate in injection solutions. The preparation is transferred to an oxy-cellulose column and the phenol is eluted with water, then determinedspectrophotometrically in the eluate. The alkaloid is then eluted from thecolumn with acid and determined spectrophotometrically.Some of the principles originally developed by Burstall and his co-workers have been applied successfully to the determination of elementssuch as molybdenum, cobalt , manganese, vanadium, nickel, and chromiumin special steels.79 The solution of the sample is applied to a cellulosecolumn, and, after elution with appropriate solvents, the elements in theeluates are determined colorimetrically.By chromatography on a transparent gel film, in which colloidal silverdichromate has been dispersed, Farlow 8o has been able to separate mixedsoluble chlorides , bromides, and iodides in single microscopic crystals orparticles.The particle in the film is moistened with water vapour where-upon it dissolves and diffuses into the film, forming the respective silverhalides in concentric rings , which separate because of solubility-productdifferences. The bands due to each halide have been developed to distinctivecolours by submitting the film to treatment with a sun lamp, ammonia, andwater vapour at elevated temperatures.The area covered by each bandis semi-quantitatively related to the amount of each halide present. Theprinciple of this method has also been used for the accurate measurementof the chloride-ion content of water-soluble particles of and g.in weight.A simplification of the ion-exchange resin method of extraction of acidsand anions from solution has been made by Moore,81 who uses long-chainamines in chloroform as the extraction medium. He is able to extractfrom aqueous solution, acids, complex metal acids, and some anioniccomplexes of polonium, plutonium, zirconium, and protactinium, by thisliquid-liquid extraction principle.5% Solutions of methyldi-rt-o tylaminesor tri-n-benzylamine in chloroform are suitable extraction solutions.In an improved method by Bkkksy 82 for the preparation of columns usedfor chromatography, the adsorbent is introduced as individual portions of77 R. J. Hall, Analyst, 1957, 82, 663.78 D. A. Elvidge, K. A. Proctor, and C . B. Baines, ibid., p. 367.7 9 G. Venture110 and A. M. Ghe, ibid., p. 343.81 F. L. Moore, ibid., p. 1660.a2 N. BCkesy, 2. analyt. Chem., 1957, 157, 272.N. H. Farlow, Analyt. Chem., 1957, 29, 881, 883HASLAM AND SQUIRRELL. 367slurry which, in the packed column, are separated from one another by piecesof filter paper; the latter are cut very accurately.Analysts faced with identification or purification problems will findvalue in the heavy-paper chromatographic technique which has beendescribed by Brownell et aZ.% for the isolation of pure compounds on thegram scale.The chromatography is carried out by conventional meansbut using a very heavy paper streaked with the mixture to be separated.After development, the resolved bands are located by taking a print fromthe chromatogram on to dry thin paper and spraying or treating with normalreagents. The corresponding band from the heavy papers is then cut outand the compound eluted with solvent.A new method has been developed by Mykolajewycz for thequantitative determination of the amount of separated substance in thedeveloped spots of paper chromatograms. A negative photocopy of thechromatogram is made in which the spots appear as white areas on a blackbackground.The intensity of the light flux through these white areas hasbeen shown to be proportional to the amount of substance in the spot andis independent of the size or form of the spot. Thus by measurement ofthe light flux by means of a suitable photocell arrangement under controlledconditions, and comparison with standard spot measurenients, an accuratemeasure of the substance in a spot can be made.White and Vaughans5 have developed an equation for the design ofliquid-liquid partition chromatographic columns, which relates theseparation factor and column characteristics with the number of theoreticalplates required for a particular separation. The use of this method permitsa more rational approach to the use of column chromatography, and thethree isomeric cresols have been satisfactorily separated in a column thusdesigned.A method has also been described for the determination of phenolin tar-acid mixtures.The method has beenapplied by Bergmann and Gruenwald 86 to the separation of polycyclicaromatic hydrocarbons. Excellent separations have been achieved by usingpaper made less polar and less hydrophilic in character by acetylation or bytreatment with alumina, propylene glycol, Vaseline, or Silicone.A method of identification of nylon and related polymers devised byClasper, Haslam, and Mooney 87 is based on hydrolysis of the sample withacid, after which the product is evaporated to dryness.The residue isdissolved in ethanol and the hydrolysis products are then separated bypaper chromatography, a mixture of .n-propanol, ammonia, and waterbeing used as the developing solvent. The various products are identifiedby observation of the chromatogram under ultraviolet light and by usingninhydrin and methyl red-borate buffer solutions as spray reagents.A chromatographic method for the separation and determination ofadipic and sebacic acids in admixture with phthalic acid, also described byPaper-chromatographic methods are numerous.83 H. H. Brownell, J. G. Hamilton, and A. A. Casselman, Analyt. Chem., 1957,29,550.84 R. Mykolajewycz, ibid., p. 1300.D. White and G. A. Vaughan, Analyt. Chim. Acta, 1957, 16, 439.8 6 E.D. Bergmann and T. Gruenwald, J. Appl. Chem., 1957, 7 , 15.87 M. Clasper, J. Haslam, and E. F. Mooney, Analyst, 1957, 82, 101368 ANALYTICAL CHEMISTRY.Clasper and Haslam,s* gives recoveries of the acids from mixtures oflOOyo & 2%. The separation is effected on a silicic acid column buffered topH 4.30 and the appropriate rc-butanol-chloroform eluates are titrated withstandard alkali. Pimelic, sebacic, and azelaic acids can be eluted approx-imately quantitatively from the column, under the same conditions of test.Valuable information about the purity of amino-acid preparations canbe obtained by paper chromatographic separation of the amino-acidimpurities and determination of the nitrogen content of the spots on the filterpaper corresponding with the individual acidsa9horizontal paper chromatography at elevated tem-peratures has been described in methods for the quantitative determinationof lactose and mannose in lactose hydrolysates, and for separation of theC,-C, volatile fatty acids. The methods are much more rapid than normalchromatographic procedures. By using a developing solvent of butanol-pyridine-water (9 : 5 : 8) galactose and glucose can be separated by twoone-hour developments at 60".Four solvent developments being used,galactoyl oligosaccharides and lactose can be separated. The volatileacids are separated as their ethylamine salts by using water-saturatedbutanol as developing solvent at 50".Ion-exchange resins are finding increased use. Sargent and Rieman 92have effected the separation of glycols by chromatography on a quaternaryammonium based ion-exchange column, using two eluting solvents, (a) asolution of NaBO,, and (b) a solution of borax.Commerical 2 : 4 : 5-trichlorophenol and 2 : 4-dichlorophenol have beenanalysed by Logie g3 using a method which involves the use of the stronglybasic anion-exchange resin De-Acidite FF in a non-aqueous solvent mediumof pure methanol.The constituents are separated either by graded elutionwith glacial acetic acid-methanol mixtures or by the use of triethylamine-acetic acid buffer solutions in methanol of known pH value. The progressof the elution is followed by ultraviolet absorption measurements.Analysts employing zone electrophoretic methods will be interested inthe method employing foam rubber as the supporting material, as describedby Mitchell and I3erzenbe1-g.~~ It has proved satisfactory for thepreparatory separation of small amounts of proteins and other electrolytes,and the samples can be recovered after ionophoresis simply by squeezingthe spongesOn gas-liquid chromatography the use of higher temperature columnshas greatly extended the scope of the method. At a working temperatureof 257" and using a gas density meter, Beerthuis and Keppler 95 havesucceeded in analysing the even-numbered saturated fatty acid methylesters from C,, to C,, in about 90 min.Such stationary phases as ApiezonIn two papers88 M. Clasper and 3. Haslam, J . Afipl. Chem., 1957, 7 , 328.89 E. Schulek and 2.L. Szab6, 2. analyt. Chem., 1957, 157, 405.90 H. R. Roberts, Analyt. Chem., 1957, 29, 1443.91 H. R. Roberts and W. Bucek, ibid. p. 1447.92 R. Sargent and W. Rieman, tert., Analyt. Ghim. Acla, 1967, 16, 144.93 D. Logie, Analyst, 1957, 82, 563.94 H. K. Mitchell and L. A. Herzenberg, Andyt. Chem., 1957, 29, 1229.95 R. K. Beerthuis and S. G. Keppler, Nature, 1957, 179, 731HASLAM AND SQUIRRELL. 369grease, silicone oils, and greases and polythene have been used on a Celitecarrier.James 96 has shown that gas-liquid chromatography is likely to be ofgreat value in helping the analyst to separate both saturated and unsaturatedfatty acids from C, to Czo. C , to C, acids are separated at either 100" or137" on columns containing a silicone oil admixed with 10% of stearic acidas stationary phase, the eluates being titrated with standard alkali.Altern-atively, they may be separated as their methyl esters on columns containingparaffin hydrocarbons or high-boiling esters as stationary phases; a gas-density balance serves as detector. The C,-Czo acids are separated astheir inethyl esters at much higher temperatures, i.e., 200" on columnscontaining an Apiezon oil as stationary phase.A millicoulometer has been described by Liberti 97 for the manual orautomatic titration of the components of a mixture separated by gas-liquidchromatography. The eluted compounds are absorbed in a suitable solutionwhere they are continuously titrated by an electrically generated reagent,using photometric, amperometric, or potentiometric methods of end-pointdetection.Compounds with an active functional group such as volatileacids, bases, thiols, and aldehydes can be titrated directly. In the absenceof active groups the organic vapours are burned and the carbon dioxide soformed titrated coulometrically.Absorption Spectroscopy (Inorganic).-As has been the case for someyears, very many papers have been noted in which analytical determinationshave been described making use of measurements in the visible and theultraviolet region. The tendency throughout seems to be to make measure-ments at specific wavelengths rather than to pursue the use of filterinstruments.Many new colorimetric reagents have been investigated. Lucena-Condeand Prat 98 have described a new reagent for the colorimetric determinationof small amounts of phosphorus, arsenic, and germanium.The reagentcontains MoV1 and MoV in the ratio 3 : 2 in acid medium containingHzSO, and HCl. The colours produced with phosphorus, arsenic, andgermanium have absorption maxima at 840, 850, and 830 mp respectivelyand obey Beer's law over convenient concentration ranges.3-Hydroxy-l-~-sulphonatophenyl-3-phenyltriazen gg has been describedas an excellent colorimetric reagent for palladium. The reagent has aremarkable tolerance for members of the platinum group and can be usedfor the determination of palladium in the presence of Ni, Fe, Co, Ag, and Cu.The reagent is very soluble and forms a stable colour over a wide pH range.Variamine-blue (4-amino-4'-me t hoxydiphen ylamine hydrochloride) hasfound application by Erdey and Szabadv5ry1O0 as a redox indicator involumetric analysis.The substance may also be used for the colorimetricdetermination of such oxidising agents, as iron(m), chromium(vI), man-ganese(vII), vanadium(v), cerium(Iv), silver, iodine, and iodate ; these96 A. T. James, Fette u. Seifele, 1957, 69, 73.9 7 A. Liberti, AnaZyt. China. A d a , 1957, 17, 247.98 F. Lucena-Conde and L. Prat, z'bid., 1957, 16, 473.99 N. C. Sogani and S. C. Bhattacharyya, Analyt. Chem., 1957, 29, 397.100 L. Erdey and F. Szabadvary, 2. analyt. Chern., 1957, la, 90370 ANALYTICAL CHEMISTRY.agents produce with the Variamine-blue a blue meriquinoid molecular com-pound of one molecule each of the oxidised form and of the reduced formof the reagent.The use of hydrazinophthdazines as reagents for the colorimetric deter-mination of iron and vanadium has been described by Ruggieri.lolHydrazinophthalazine and dihydrazinophthalazine yield red-violet com-plexes with ferric ion, in sodium acetate at a pH of 11-2; Beer's law isobeyed in quantitative measurements made at 535 mp with hydrazino-phthalazine.Both reagents yield a straw-yellow colour with vanadiumand the vanadium hydrazinophthalazine complex at pH 5.5 in sodiumacetate buffer gives a colour obeying Beer's law fairly closely at A,,,. = 442mp,Aluminium has been rapidly determined in aluminium brasses andbronzes by Steele and England lo2 using the colorimetric reaction withEriochrome-cyanine RC after separation from interfering elements bysodium hydroxide treatment of an acid solution of the sample.Ferric salts, in buffered solution, form green complexes soluble in zsopentylalcohol with 8-hydroxy-7-iodoquinoline (ferron) and tri-n-butylammoniumacetate.The coloured solutions which are obtained are of high stability-The influence of other metals and of certain masking agents on the test hasbeen studied.lo3The new reagent for phosphorus-o-dianisidine molybdate-has been usedby Welch and West lo4 in the production of sensitive methods for the detectionof small amounts of organic phosphorus compounds containing as little as 0.2 yof combined phosphorus. The procedures described are applicable to acids,esters, acyl halides, and anhydrides together with their thio-analogues.Since its introduction twenty years ago, toluene3 : 4-dithiol has foundgreat favour as a reagent for tin.The general usefulness of the reagent hasnow been extended by a study of its reactions in acetate buffer and alkalinesolution by Clark.lo5 As a result of this it is likely to prove a useful reagentfor copper, cobalt, iron(II), antimony(v), and thallium. The S-dibenzoyland the S-diacetyl derivative are particularly useful in their colour reactionswith palladium(II), rhenium(vII), tellurium(Iv), selenium(Iv), and iridium.The S-diacetyl derivative and the zinc complex of toluene-3 : 4-dithiol arelikely to prove useful sources of the reagent itself which is rather unstable.Fast-grey RA is a very sensitive reagent for copper.Two moles of the acidunite with one mole of copper to form a coloured product which is measuredat 555 mp. The test, due to Khalifa,lo6 is capable of detecting 0.02 p.p.rn.of copper in solution in the presence of many cations: the interference ofiron may be avoided by the addition of ascorbic acid. With appropriaternodification,lo7 the same reagent can be used for the correspondingdetermination of very small amounts of quinquevalent vanadium.Interfering elements have been tabulated.lol R. Ruggieri, Analyt. Chim. Acta, 1957, 16, 242, 246.102 M. C. Steele and L. J. England, ibid., p. 148.103 M. Ziegler, 0. Glemser, and N. Petri, 2. analyt. Chem., 1957, 154, 170.lo* C. M. Welch and P. W. West, Analyt.Chem., 1957, 29, 874.105 R. E. D. Clark, -4nalyst, 1957, 82, 177, 182.loti H. Khalifa, 2. analyt. Chem., 1957, 158, 103.107 H. Khalifa and A. Farag, ibid., p. 109HASLAM AND SQUIRRELL. 37 1Fast-grey RA has also proved to be a very sensitive reagent for zir-conium.lo8 The purple reaction product in 0.2~-hydrochloric acid ismeasured at 580 mp. Metals such as U, Co, Al, Th, Bi, Zn, the alkali metals,and rare earths do not interfere, but nickel and copper do. The interferenceof appreciable quantities of iron may be avoided by the use of ascorbic acid.Methods have also been set out for the use of this dye in the determinationof bismuth log and molybdenum.l1°New methods and techniques in visible absorptiometric analysis havealso been very numerous and cover a wide range of determinations as thefollowing few examples will show.The metal indicator Eriochrome-black T has long been used as an end-point indicator in the titration of metals with EDTA.The reaction ofmicrogram quantities of many metals with Eriochrome-black T and thebehaviour of the reaction products with complexing agents and othersubstances such as potassium cyanide, carbamates, formaldehyde, andmagnesium complexone have been utilised by Berger and Elverslll inproviding a simple scheme of identification of certain cations.Diffculties arise in the visual EDTA titration of calcium with murexideas indicator, and of calcium and magnesium with Eriochrome-black T,particularly when other complexing agents such as potassium cyanide arepresent.These difficulties are avoided in an optical method designed byWallraf,l12 in which a parallel beam of light passes through a metal inter-ference filter of transmission maximum 620 mp, thence through a beakercontaining the solution under test, which is stirred magnetically. Theissuing light then falls on a selenium cell and the resulting current changeswhich take place in the course of the EDTA titration are measured on asensitive galvanometer.When p-phenylenediamine is oxidised by ferric chloride in the presenceof sulphide Lauth’s violet is formed. This reaction is inhibited by smallamounts of thiosulphate and advantage has been taken of this time ofinhibition in the development of a useful method of thiosulphate deter-mination.l13 The times of inhibition caused by known amounts of thio-sulphate under controlled conditions are measured as a calibration, and thesample then examined by a similar clock reaction.Heterometric titrations, Le., titrations to the point of maximum turbidity,have been utilised in several new analytical tests devised by Bobtelsky andRafailoff .l14 The heterometric reaction between lead and sodium diethyl-dithiocarbamate has been studied, and the principle used in a micro-methodfor the determination of lead in the presence of even more than 994% ofmany other cations.A titration takes of the order of 10 minutes and anerror of O-l-O% is reported, if the specially designed “ heterometer ” is used.The determination of bisrnuth1l5 in the presence of many other ions108 H.Khalifa and M. R. Zaki, 2. afialyt. Chem. 1957, 158, 1.100 H. Khalifa, Analyt. Chim. Acta, 1957, 17, 318.110 H. Khalifa and A. Farag, ibid., p. 423.111 W. Berger and H. Elvers, 2. analyt. Chem., 1957, 154, 114.112 M. Wallraf, ibid., 1957, 156, 332.113 J. B. Risk and J . D. H. Strickland, Analyt. Chem., 1957, 29, 434.114 M. Bobtelsky and R. Rafailoff, AnuZyt. Chim. Acta, 1957, 16, 321.115 Idem, ibid., p. 488372 ANALYTICAL CHEMISTRY.has been carried out on the micro-scale by heterometric titration with sodiumdiethyldithiocarbamate in the presence of complexing agents for the intes-fering cations. The end-point of the titration was shown to occur at thernole-ratio Bi : sodium diethyldithiocarbamate = 1 : 2, without dependenceon the complexing agent used.Excellent results were obtained, exceptin the presence of copper and antimony, and a complete titration could becarried out in 15 minutes. This work has also been extended to the deter-mination of cadmium.u6A very sensitive test €or titanium, which is specific in the presence ofmany light and heavy metals, has been suggested by Ziegler and Glern~er.~’Titanium in the presence of sulphosalicyclic acid and tetraphenylarsoniumchloride yields, with chloroform, a yellow chloroform extract.A new method for the separation and determination of traces of boron 118involves extraction of the boron as the rnethylene-blue fluoroborate complexwith dichloroethane and measurement of the colour at 645 my in a spectro-photometer. The method has been applied to the determination of boronin silica after a preliminary decomposition of the sample by means of hydro-fluoric acid, hydrogen peroxide, and ammonium hydrogen difluoride(FNH,,FH) in the presence of a copper(I1) chloride catalyst contained in apolythene reaction bottle.The voluminous work involving absorptiometric measurement in thevisible region has included a method for the determination of tellurium inlead and lead alloys by Fletcher and Wardle 119 involving the precipitationof the tellurium from the solution of the sample in bromine-hydrobromicacid mixture. The tellurium is subsequently dissolved, and finally theabsorption of the bromide is measured at 442 my in the presence of adefinite amount of hydrobromic acid.An adaptation 120 of the principle ofthe test enables bismuth to be determined in lead and lead alloys.A method published by Aldridge and Cremer 121 which is useful for thedetermination of diethyl- and triethyl-tin in mixtures of diethyltin dichlorideand triethyltin sulphate and which may have other applications is basedupon direct reaction of the compounds with dithizone. The aqueoussolution of the mixture is treated with a borate EDTA buffer at pH 8-4 andchloroform; the chlorofonn phase is separated and treated with dithizoneand fresh borate EDTA buffer before measurement of the triethyltincomplex at 610 mp. The aqueous phase is treated with chloroform anddithizone previous to measurement of the diethyltin complex at 510 my.The spectrophotometric determination of trace amounts of zinc as thezinc complex with apy8-tetraphenylporphin complex has been describedby Banks and Bisque.122 The complex is formed in glacial acetic acid andis particularly useful for the determination of zinc in cadmium, magnesium,rare earths, beryllium, iron, yttrium, and the alkali metals.116 M.Bobtelsky and R. Rafailoff, Analyt. Chim. Acta, 1957, 17, 267.117 M. Ziegler and 0. Glemser, 2. analyt. Chem., 1957, 157, 17.11* L. Ducret, Analyt. Chim. Acta, 1967, 17, 213.118 N. W. Fletcher and R. Wardle, Analyst, 1957, 82, 743.lZo Idem, ibid., p . 747.121 W. N. Aldridge and J. E. Cremer, ibid., p. 37.lz2 C. V. Banks and R. E. Bisque, Analyt. Chem., 1957, 29, 622HASLAM AND SQUIRRELL.373A method for the determination of inorganic azides in the presence ofother material, e.g., lead a i d e paint primers, has been developed by Robersonand Austin.123 The principle of the method involves conversion of theazide into hydrazoic acid with acid, followed by distillation into an acidifiedferric nitrate solution and photometric measurement of the reddish-brownferric azide colour formed at 460 my. Thiocyanates interfere in the test.A useful procedure1% for the direct determination of small amountsof copper in fuel oil and petroleum products may well be used for thedetermination of copper in other organic liquids. The liquid under testis treated with propan-2-01 solution of neocuproine (2 : 9-dimethyl-1 : 10-phenanthroline) and quinol and diluted with chloroform.. The absorbanceat 454 mp of the copper-neocuproine complex solution is then measured.The method appears remarkably free from interference.A colorimetric method for the determination of uranium has beensuggested by Blanquetlz5 based on the measurement at 415 mp of thecoloured complex of uranium with dibenzoylmethane formed in aqueouspyridine in the presence of EDTA and tartaric acid. Conditions have beenworked out which avoid interference from other elements and the methodis thus particularly useful for the determination of uranium in mineral ores.One of the disadvantages of many of the methods of colorimetric deter-mination of sexavalent uranium is their lack of sensitivity. A method isput forward by Foreman, Riley, and Smith126 in which many interferingelements are first removed by preliminary treatment of the uranium-con-taining solution with cupferron and extraction in acid medium.Otherinterfering substances are side-tracked by the addition of EDTA beforeextraction of the uranium as its diethyldithiocarbamate complex. Theuranium is recovered from the solution of the complex, then reduced to thequadrivalent condition with lead shot before application of the very sensitiveThoronol test for quadrivalent uranium.Use of tributyl phosphate has been made in the separation of uraniumfrom thorium, bismuth, and a variety of ores.127 Extraction from hydro-chloric acid solution permits separation from thorium, and extraction fromnitric acid solution separation from bismuth and other elements.Conditionshave been worked out which give an extract from nitric acid solution pureenough to enable the uranium to be determined by the 8-hydroxyquinolinespectrophotometric method.Dozinel128 describes how antimony, when present in pure and electrolyticcopper in the range 0~0001-0~003%, may be determined after solution ofthe sample in hydrochloric acid-hydrogen peroxide and removal of theexcess of peroxide.. The solution is reduced with sulphurous acid, then theantimony is oxidised with ceric sulphate to the quinquevalent condition.This antimony is extracted with isopropyl ether and treated with RhodamineB solution ; the coloured reaction product is measured photometrically.123 C. E. Roberson and C. M.Austin, Analyt. Chem., 1957, 29, 854.124 D. M. Zall, Ruth E. McMichael, and D. W. Fisher, ibid., p. 88.126 J. K. Foreman, C. J. Riley, and T. D. Smith, Analyst, 1967, 82, 89.127 A. R. Eberle and M. W. Lerner, Analyt. Chem., 1957, 29, 1134.128 C. M. Dozinel, 2. analyt. Chem., 1957, 157, 401.P. Blanquet, Analyt. Chim. Acta, 1957, 16, 44374 ANALYTICAL CHEMISTRY.The problem of determination of arsenic and phosphorus in copper-basealloys in the ranges 0-0.6% and 0-0.1% respectively has been successfullysolved by Baghurst and N0rman.1~~ The method, which requires nopreliminary separation of the elements, is based on the development of themixed heteropoly-acids with molybdenum and vanadium in acid solutionsof differing strength. The molybdovanadophosphoric acid is first formedin nitric acid solution of sufficient strength to prevent formation of thearsenic complex.Both complexes are then formed at a lower acid concen-tration, measurement of the colours made, and the readings referred to theappropriate calibration curves.A useful method for the rapid colorimetric determination of sulphatein the range 2-400 p.p.m. has been developed by Bertolacini and Barney.13*The method is based on reaction of the slightly soluble barium chloroanilate,with sulphate to liberate the highly coloured acid chloroanilate ion in 50%ethyl alcohol solution, after a preliminary removal of interfering cationswith ion-exchange resin.An important problem is concerned with the determination of mercuryand mercury compounds131 present as vapour, spray, or dust in air inconcentrations around the usually accepted “ toxic limit ” of 100 pg.percubic metre. The vapour of mercury is taken up by iodised active carbonand the mercury-bearing dust is trapped in a mineral wool filter. The activecarbon and mineral wool, in the presence of iron powder, are subsequentlyheated in a stream of carbon monoxide, generated from sodium oxalate, andthe mercury vapour evolved is determined by the colorimetric reactionwith selenium sulphide paper.A very useful procedure has been developed by Chirnside, Cluley, andProffitt 132 for the determination of a few p.p.m. of boron in nickel. Thesample is made the anode of a mercury cathode electrolysis apparatus;this enables the nickel and interfering elements to be removed in the presenceof the minimum amount of sulphuric acid.In its turn this simplifies theapplication of the curcumin-oxalic acid test to boric acid which has beenstudied in considerable detail.Very small amounts of cobalt in a whole host of substances such asnickel, chromium alloys, glasses, iron pyrites, zinc oxide, etc., may bedetermined by a method involving the production of tributylammoniumhexathiocyanatocobaltate(~~).~~~ This substance is extracted with isopentylacetate, and the colour measured at an appropriate wavelength.In a new method for the determination of osmium, Steele and Yoe134have used the naphthylaminesulphonic acids. The osmate(v1)-naphthyl-aminesulpfionic acid complexes show an absorption peak around 560 mpand adhere to Beer’s law from 0.1 to 6.0 p.p.m.of osmium. The osmiumcan be separated from interfering elements by distillation of the tetroxide.Several of the complexes have sensitivities as high as 1 in 20,000,000.H. C. Baghurst and V. J. Norman, Analyt. Ckem., 1957, 29, 778.130 R. J. Bertolacini and J. E. Barney, jun., ibid., p. 281.131 G. A. Sergeant, B. E. Dixon, and R. G. Lidzey, Analyst, 1957, 82, 27.132 R. C. Chirnside, H. J. Cluley, and P. M. C. Proffitt, ibid., p. 18.133 M. Ziegler, 0. Glemser, and E. Preisler, 2. analyt. Chem., 1957, 158, 358.lS4 E. L. Steele and J. H. Yoe, Analyt. Chem., 1957, 29, 1622HASLAM AND SQUIRRELL. 375Ultraviolet spectroscopy has been the basis of many excellent methodspublished throughout the year.The determination of lead in rubber and compounding materials on asemimicro-scale has been facilitated by a method due to Kress 135 involvingthe absorptiometric measurement of the solution of the ash or extract of thematerial in 50% hydrochloric acid.Measurement is made at 250, 270, and289 mp; after correction for the presence of iron and other cations mathematic-ally, the concentration of lead is calculated. The method appears valid in thepresence of copper up to 1/10 of the lead content. A similar spectrophoto-metric method has been developed by Grossman and Haslam136 for therapid determination of lead in PVC compositions. The absorption due tolead chloride is measured at 270 mp in a hydrochloric acid extract of anethylene dichloride solution of the sample.A slight modification of thismethod avoids interference due to any iron present in the composition.The fact that boric acid causes a very marked change in the ultravioletabsorption of chromotropic acid in aqueous solution has been made thebasis of an excellent method for the determination of a few p.p.m. of b0r0n.l~'The addition of boric acid causes a decrease in absorption of a chromo-tropic acid solution in the range 355-380 mp with a point of maximumdecrease at 361.5 mp. A determination of a differential spectrum of asolution of chromotropic acid at 361.5 mp with and without the boric acidsample solution is thus utilised, for the determination of boron, after suitablecalibration experiments have been carried out.Uranium(v1) can be extracted as a complex from sodium nitrate solutionat pH 3.0 into a 25% solution of tributyl phosphate in an inert solvent,138and after being thus separated from interfering elements the uranium canbe determined spectrophotometrically by measurement of the complexsolution at 250 mp.A most useful method for the determination of microgram quantities ofhalide in aqueous solution has been developed by Chapman and Sherwood 139based on direct ultraviolet absorbance measurement of the complexes formedwith palladous sulphate. Mixtures of halides have been separately deter-mined after selective oxidation with manganese dioxide or lead dioxide.Procedures are given for the conversion of organic halogen compounds intowater-soluble inorganic halides by treatment with disodium diphenyl.Finally, a useful application of infrared spectroscopy to inorganicanalysis has been made in the determination of sulphate ion in the range40-80 y in aqueous solution.The solution is freeze-dried with potassiumbromide, and a disc prepared from the resulting powder by the usual vacuum-high pressure technique. The method by Han Tai and isobviously easily calibrated.Ahsorption Spectroscopy (Organic) .-Applications of absorption spectro-scopy to organic analysis have also been numerous. Amongst the many135 K. E. Kress, Analyt. Clzem., 1957, 29, 803.136 S. Grossman and J. Haslam, J . Appl. Chem., 1957, 7, 639.137 D. F. Kuemmel and M. G. Mellon, Analyt. Chem., 1957, 29, 378.138 B.E. Paige, M. C. Elliott, and J. E. Rein, ibid., p. 1029.13p F. W. Chapman, jun., and R. M. Shenvood, ibid., p. 172.140 Han Tai and A. L. Underwood, ibid., p. 1430376 ANALYTICAL CHEMISTRY.useful communications published throughout the year have been thefollowing .New and extremely sensitive colorimetric procedures for the detectionand determination of unreacted isocyanate groups in urethane-basedpolymers have been worked out by Kubitz.lgl In the quantitative methodthe residual isocyanate is treated with an excess of n-butylamine, and theexcess then determined colorimetrically after treatment with malachite-green.For the rapid qualitative detection of isocyanate, a previously preparedcolourless secondary mine derived from malachite-green is used, and when asample containing free isocyanate is treated, a coloured product is produced.A novel method has been put forward by Saville 142 for the determinationof phosphorylating or acylating agents such as phosphorofluoridates, tetra-alkyl pyrophosphates, acetic anhydride, and benzoyl chloride.a-Oxo-aldoximes such as mononitrosoacetone react rapidly in slightly alkalinesolution with the agent, resulting in quantitative production of cyanidewhich is then determined colorirnetrically by the pyridine-pyrazolone test.The colour reaction of o-phthalates and succinates with quinol in thepresence of concentrated sulphuric acid has been put forward by Swann 143as a qualitative and quantitative test for these substances in plasticisers andsynthetic resins blended with alkyds.Quinazarin is formed with phthalatesand dihydronaphthazarin with succinates. For phthalates the reactionis carried out at 145" and the yellow colour, A,,,. = 480 mp, extracted withbenzene. On shaking with aqueous alkali the colour changes to violet,A,,,. = 575 mp. For succinates the reaction temperature is reduced to135" and the benzene extracts obtained are red in acid media and blue aftera,lkali-washing. The strict control of experimental conditions required forquantitative work is described.Organophosphorus compounds have featured in the analytical literature.Diisonitrosoacetone has been used by Sass et aZ.lU for the detection anddetermination of small quantities of organophosphorus halides, acid an-hydrides, and acetylating agents.The reagent forms a coloured complexmeasurable at 486 or 580 mp with as little as 1 y of compound in a 4 ml.portion of sample. A sensitive method also for the determination of organo-phosphorus compounds 145 has been based on the reduction of the phosphorusto phosphine with lithium aluminium hydride, followed by reaction of thephosphine vapours with silver nitrate or gold chloride on paper. Comparisonof the coloured stains produced can be made visually or by photometricmeasurement, and microgram amounts of organophosphorus compoundscan be detected.Hershenson and Hume 1*6 have determined small amounts of aliphaticamines in solution photometrically by taking advantage of the characteristicabsorption band from 750 to 950 mp due to the complex which is formed141 K.A. Kubitz, Analyt. Chem., 1957, 29, 814.142 B. Saville, Analyst, 1957, 82, 269.143 M. H. Swann, Analyt. Chern., 1957, 29, 1352.1*4 S. Sass, W. D. Ludemann, B. Witten, V. Fischer, A. J. Sisti, and J. I. Miller,lP5 F. T. Eggertsen and F. T. Weiss, ibid., p. 453.146 H. M. Hershenson and D. N. Hume, ibid., p. 16.ibid., p. 1346HASLAM AND SQUIRRELL. 377when the amine solution is added to an alcoholic solution of cupric chloride.Should the amine solution be in aqueous media or interfering basic substancesbe present, then the amine may be extracted with chloroform after theaddition of sodium carbonate and the cupric chloride reaction carried outin an alcohol-chloroform medium.Kapur et aZ.147 have noted how the colorimetric determination of vanillinhas been achieved by using absorptiometric measurement at 432434 myof the complex formed with thiobarbituric acid in phosphoric acid media.The method will detect as little as 0.2 pg./ml.of vanillin in 92% phosphoricacid, and may also be applied to the estimation of other aldehydes.A rzaction more specific for propylene glycol than previously publishedmethods for the determination of vicinal glycols has been described byJones and R i d d i ~ k . l ~ ~ The method is based on dehydration with sulphuricacid, which results in rearrangement of the propylene glycol to ally1 alcoholand the enolic form of propionaldehyde. This reaction mixture forms aviolet complex with ninhydrin suitable for quantitative spectrophotometricmeasurement at 595 mp.This coloured complex is specific for propyleneglycol and its polymers in mixtures of glycols.The determination of anthracene in impure anthracene containingcarbazole and phenanthrene has been accomplished by Fauss149 using amethod which involves (1) the preparation of a cell containing a definiteconcentration of pure anthracene in solution and (2) the addition of puresolvent to a second cell containing a known concentration of the impureanthracene until the absorptions of the two liquids are identical at a wave-length of 375 mp. A special cell has been constructed which permits stirringof the solution of the impure anthracene. It is claimed that the methodhas advantages over the differential procedure.o-Phenylphenol (2-hydroxydiphenyl) , after preliminary isolation, mayby determined (a) by taking advantage of the ultraviolet absorption of thephenol at two different wavelengths both before and after treatment withsodium hydroxide, (b) by measurement of the strong blue-violet fluorescenceof the phenol when irradiated in ultraviolet light, and (c) by measurementof the colour obtained on coupling of the phenol with the stabilised diazo-compound Brentamine fast-red GG.150Biggs,151 also on the subject of phenols, has proposed a method whichmay prove to be very useful in the identification of weak acids such ascertain phenolic substances.The ultraviolet absorption of the phenol ismeasured at a particular wavelength in acid and alkaline solutions as wellas in a buffered solution of pH close to the pH of the particular phenolicsubstance.From these data the degree of ionisation of the phenol iscalculated and compared with the values for pure substances.Emission Spectroscopy.-Under this heading Scharrer and Judel 152 haveI*' N. S. Kapur, K. M. Narayanan, G. S. Bains, and D. S. Bhatia, Chem. and Ind.,14* L. R. Jonesand J. A. Riddick, Analyt. Chem., 1957, 29, 1214.149 R. Fauss, 2. analyt. Chem., 1957, 155, 11.l50 D. Harvey and G. E. Penketh, Analyst, 1957, 82, 498.151 A. I. Biggs, ibid., p. 274.152 K. Scharrer and G. K. Judel, 2. analyt. Chem., 1957, 156, 340.1957, 1272378 ANALYTICAL CHEMISTRY.put forward a method for the spectrochemical determination of traceelements such as Ag, Co, Cu, Mn, Mo, Ni, Pb, V, and Zn in soils, fertilisers,and biological material. After suitable preparation of a solution of thesubstance with added iron or cadmium as additional elements, the Ag, Co,etc., are precipitated as their pyrrolidine dithiocarbamates at a definite pHand in the presence of sulphosalicylic acid.The chloroform solution of thedithiocarbamates is evaporated and ashed and the Ag, etc., then determinedspectrographically in the ash by comparison of the intensity of a suitableline of the element under consideration with that of a particular line ofiron or cadmium.The effect of phosphoric acid in depressing the flame emission of calciumcompounds is made use of in a method due to Erdey and Svehla 153 for thevolumetric determination of calcium using a flame photometer.A specialburner restricts the loss of calcium solution in the test. Flame photometricreadings corresponding with known additions of standard phosphoric acidsolution to the calcium solution under test are plotted against volume oftitrant.Also on the subject of flame photometry, in the determination of mag-nesium it has been shown by Knutson l* that it is desirable to use a car-burising flame containing carbon produced from appropriate proportionsof oxygen and acetylene. Under these conditions the sensitivity obtainedwith the 2852A line of magnesium relative to the background is muchincreased. Errors due to the presence of phosphate and sulphate ions arelargely eliminated by the presence of an excess of calcium ions.MICRO-ANALYSISProgress is still being made in the determination of the individualelements in organic compounds by micro-chemical procedures.In viewof the fact, however, that there is a tendency to require the analysis of smallerand smaller amounts of sample, it is likely that Unterzaucher’s newprocedure155 for the determination of carbon and hydrogen in organiccompounds or a modification of it will be of real significance. The abovemethod is capable of determining carbon : hydrogen ratios on as little as0 . 1 4 . 3 mg. of an organic substance, without weighing. The substanceis burnt in a stream of air over copper oxide. The combustion products,containing carbon dioxide and water from the substance and excess ofoxygen, are passed over heated copper to remove this oxygen; the wateris frozen out whilst the carbon dioxide passes on to be determined by passageover heated carbon and application of the volumetric Unterzaucher procedure.After this the water is melted and determined similarly.The interferenceof nitrogen, sulphur, and chlorine is avoided by appropriate arrangementof the combustion and absorption train.In a new combustion method by M&zor156 for the determination ofcarbon, hydrogen, and fluorine in a single sample of organic compound,minium is used to bind the hydrogen fluoride and as the oxidant. ThelS3 L. Erdey and G. Svehla, 2. andyt. Chem., 1957, 154, 406.154 K. E. Knutson, Analyst, 1957, 82, 241.166 J. Unterzaucher, Mikrochim.Acta, 1957, 448.156 L. MBzor, ibid., p. 113HASLAM AND SQUIRRELL. 379minium is employed as a layer on the inner wall of a sintered alundumtube which is placed in the empty glass combustion tube. The pyrolysisproducts from the combustion boat pass through a platinum tube over theminium at a temperature of 550-570", whereat the carbon and hydrogenare completely oxidised and fluorine bound as lead fluoride. The carbondioxide and water formed are determined in the usual way, and the fluorineby dissolving the minium layer from the apparatus and precipitating andweighing as lead chlorofluoride.A very fast and accurate Dumas method for the micro-determinationof nitrogen in solids, aqueous solutions, and biological fluids has been workedout by Kirsten.157 The sample is pyrolysed in carbon dioxide, and theproducts subsequently burned over nickel oxide before collection of thegases in a specially designed nitrometer.A complete analysis takes only16 minutes.Again, whilst retaining the general principles of the micro-Dumas methodfor the determination of nitrogen in organic compounds, changes in the typeof filling and the introduction of automatic traverse methods of combustionand breakdown of the sample have accelerated the test considerably.Nitrogen determinations may now be made in 35 minutes by Charlton'sprocedure.15*A new method15B for the micro-determination of chlorine in organiccompounds involves the preliminary conversion of the chlorine into chlorideand subsequent isolation of this chloride as silver chloride.This is dissolvedin ammonia and reprecipitated in emulsion form with acid before titrationwith standard iodide solution, starch and iodine in chlorobenzene beingused as indicator.Burger160 has presented a new specific and sensitive method for thedetection and quantitative determination of silver which depends on thereaction, at boiling temperature, of an ammoniacal solution of the silversalt with an alcoholic solution of 2 : 4-dinitro-l-thiocyanatobenzene. Underthese conditions an insoluble precipitate of the silver salt of 2 : 4-dinitro-thiophenol is produced.Analysts dealing with bacterial cellulose will be interested in a new testfor its estimation which has beenodevised by Dearing.161 The samples areprepared by treatment with sodium hydroxide, washed, and dried beforetreatment of an aqueous suspension of the dried material with sulphuric acidat the temperature of boiling water under controlled conditions.The pinkcolour produced is measured at 520 mp after centrifuging the suspension, andthe optical density compared with a standard curve prepared by using glucose.The determination of oxygen has received attention during the year.Further work has been carried out on the direct determination of oxygenin organic compounds by reaction with fluorinating agents and measurementof the molecular oxygen released. Sheft and Katz 1 G 2 have used BrF2SbF,,15' W. J. Kirsten, Analyt. Chenz., 1957, 29, 1084.lS8 F. E. Charlton, Analyst, 1957, 82, 643.W. Pilz, 2.analyt. Cheqn., 1957, 155, 423.160 K. Burger, MzRrochim. Acta, 1957, 310.161 G. G. Dearing, Nature, 1957, 179, 579.162 I. Sheft and J. J. Katz, Analyt. Chem., 1957, 29, 1323380 ANALYTICAL CHEMISTRY.a complex which is prepared simply from antimony pentduoride andbromine trifluoride. The organic compound is heated with the BrF2SbF,at 500' with thorough shaking, and the molecular oxygen released measuredtensimetrically. The method appears applicable to solid, liquid, or gaseoussamples.In a series of papers Potter and White163 have critically reviewed anddescribed improvements in the methods for the micro-determination ofdissolved oxygen in water at low concentrations of the order of 0.01 p.p.m.In the first paper the Winkler method with an amperometric finish for theiodometric titration is advised with certain amendments to avoid errorsdue to interfering substances.In the second paper the errors introducedby the use of the McLean sampling vessel are discussed and a new apparatusis described by which a precision of -J=O.O02 p.p.m. can be obtained. Amodification for use with warm water is also described. Paper 3 containsa description of a sensitive electrical circuit for use in the amperometrictitration of iodine with a sensitivity of 0.01 pg. of iodine per 100 ml. solution,no interference being caused by 2 p.p.m. of ferrous, ferric, or cupric ions.The titration of 10-7~-thiosulphate with lO-%-iodate is practicable. Paper4 describes a test of the efficiency of the Winkler method at concentrationsin the range 0.0007-0.0544 mg.of 02/litre. In paper 5 an ion-exchangemethod for the effective removal of interfering ferrous ions in the Winklerreaction is described, together with a referee method for the determinationof dissolved oxygen in water, with a precision of &04015 p.p.m.Booth, Bryant, and Parker1@ have successfully extended the well-known vacuum fusion method to the micro-determination of oxygen andhydrogen in sample weights of the order of 20 mg. of boron, beryllium,copper, chromium, iron , silicon, tantalum, thorium, titanium, uranium, andzirconium. The metal is brought into contact with platinum containingdissolved carbon at 1880" and the resulting carbon monoxide, hydrogen,and nitrogen, with small amounts of carbon dioxide, are pumped away andisolated, before analysis by a low-pressure method. The carbon monoxideis converted into carbon dioxide over Hopcalite, the carbon dioxide frozenout, then the carbon monoxide, and hence the oxygen, determined by takingaccount of the pressure change before and after this treatment. Hydrogenis determined by a similar process involving its removal by passage overheated palladium at 350400'.In general, the results for nitrogen do notappear to be particularly trustworthy.Several micro-qualitative tests worthy of note have been recorded.A spot test for micro-amounts of P5+ has been developed by Zechner165based on the reaction of phosphorus with quinoline molybdate impregnatedfilter-paper to form quinoline phosphomolybdate. The reagent paper iseasily prepared and 1 pg.of phosphorus can be detected.Two substituted naphthylamines 166 have been successfully used asspot-test reagents, viz. , 4-nitro-l-naphthylamine for mercuric mercury in163 E. C. Potter, J . A$@. Chem., 1957,7,285,297; E. C. Potter and J. F. White, ibid.,pp. 309, 317, 459.164 E. Booth, F. J. Bryant, and A. Parker, AnaZyst, 1957, 82, 60.166 S. Zechner, Mikrochim. Acta, 1957, 159.166 J. L. Garnett and L. C. Lock, Amulyt. C h h . Acts, 1957, 17, 351HASLAM AND SQUIRRELL. 381which CeIV i s the only other element known to interfere, and l-nitroso-2-naphthylamine for CeIv for which ion the test appears to be specific.The reaction between nitrate and chromotropic acid in the presence ofexcess of sulphuric acid has been utilised in the development of a usefulspot test for nitrate by West and Sa,rrnay167 At a dilution of 1 : 200,000as little as 0.2 pg.of nitrate ion gives a yellow colour, and interference fromnitrites and oxidising agents is eliminated by a preliminary treatment ofthe sample with sodium sulphite, sulphuric acid, and sulphamic acid.Finally, a very specific spot test for vanadium has been developedla8which is based on the production of a turquoise-blue colour with sodiumsalicylate in syrupy phosphoric acid solution.MISCELLANEOUS ANALYSISA method has been described for the determination of carbon and carboncompounds in br0mine.1~~ The bromine sample is passed in a stream ofoxygen through a combustion tube at 1000" to effect conversion of thecarbon into earbon dioxide.The bromine is then frozen out and the carbondioxide purified by passing through copper sulphate, manganese dioxide,and anhydrone, followed by absorption on Ascarite.By a rather novel procedure put forward by Jennings and Osborn170carbon dioxide in water in the range 0.01--0-10 mg. per litre may be deter-mined by aspiration of the acidified water with carbon dioxide-free air.The carbon dioxide evolved is absorbed in sodium hydroxide solution,which is subsequently titrated with N/lOO-acid. The acid used betweenpH 8.3 and 5.0 is a measure of the carbon dioxide in the water under test.The commercial product chlorbenside, an acaricide for red spider, consistsessentially of a mixture of p-chlorobenzyl $-chlorophenyl sulphide with asmaller proportion of o-chlorobenzyl @-chlorophenyl sulphide.In itsassay 171 the isomeric sulphides are oxidised to the corresponding sulphonesand weighed. The melting point of the product is determined, and theproportion of active para-para-sulphide compound deduced by referenceto appropriate melting point curves of mixtures of the pure sulphones.Fluorbenside is examined similarly.A method has been described 172 whereby the photometric titration dataobtained after the end-point of acid-base titrations can be platted to givea stoicheiometric end-point by extrapolation. The method is of particularuse in the titration of weak bases in water and the titration of essentiallynon-basic compounds like urea or amides in acetic acid.Great accuracyis claimed for the method owing to the sensitivity of the photometricmeasurements on which the plot is based.RADIO-CHEMISTRYThe pioneer work in radio-chemical analysis, a considerable proportionof which has been carried out in this country, is now bearing fruit and there16' P. W. West and P. L. Sarma, Mihrochinz. Acta, 1957, 506.lB8 V. P. R. Rao and G. G. Rao, 2. azzaEyt. Ghem., 1957,156, 100.lB0 M. Codelland G. N~rwitz, Analyf. Chem., 1957, B, 967.170 P. P. Jennings and E. M. Osborn, AnaZyst. 1957, 82, 671.1'1 D. J. Higgans and W. H. Stephenson, ibid., p. 435.172 C. Rehm and T. Higuchi, Analyt. Chem., 1957, 29, 367382 ANALYTICAL CHEMISTRY.is no doubt that with the introduction of more simplified equipment radio-chemical methods will in the near future become well-established proceduresin many analytical laboratories.The problem of preparing thin deposits of a-emitting elements fromorganic solvents has been largely overcome in a method described byThe solution in an organic solvent is evaporated on a tray the periphery ofwhich is heated so as to give a suitable temperature gradient across the tray,causing smooth evaporation of the solvent within the boundary of theheated periphery.In addition, a method has been described by Wagner, Pollack, andDonahoe 174 for the measurement of radioactive precipitates on filter paperby examination of both sides of the paper.Consideration must be givento thickness of paper and precipitate and close geometry conditions ofcounting must be used.A recording apparatus designed by Schram and Lombaert 175 facilitatesthe determination of soft radiations (14C,35S) in aqueous medium, for example,in chromatographic eluates.The solution is spread in a thin layer incontact with a plastic scintillator coupled to a coincidence circuit. Theefficiency of the instrument is stated to be comparable to that of a thinend-window G.M. counter in the absence of auto-absorption,Amongst the many useful applications of radiochemical analysis is amethod for particle-size determination by Abraham et aZ.176 capable ofbeing placed on an automatic basis and making use of a sedimentationprocedure in conjunction with radio-activation. The powder is neutron-bombarded and the activity which radiates from a thin laminate is used as ameasure of the weight of material in the laminate.The advantages of themethod are its speed and reliability and the fact that it can be used withreactive fluids such as liquid metals, water, and organic liquids.In the separation of small amounts of magnesium from iron withammonium sulphide, the question has been raised as to whether correctresults for magnesium have been obtained owing to compensating errors,i.e., a certain amount of co-precipitation of magnesium with the ironsulphide having been compensated for by titration of foreign ions withEDTA in the magnesium test. This is not the case as experiments byGamsjager and R e i ~ h e r t , l ~ ~ using active magnesium, have proved.In connection with the analysis of barium [14C]carbonate and 14C-labelled cyanide prepared from it, methods of general applicability to14C-labelled compounds have been worked out by Moyer and Isbell.178Total reactivity is taken by a direct count and by count measurement ofthe carbon dioxide liberated by wet oxidation after absorption in alkalineethylene glycol. A count of carbon dioxide evolved by acid treatmentof the carbonate after similar absorption gives a basis for its evaluation.The specific count for 14C-labelled cyanide .is taken by reaction with a173 D.G. Tuck, Analyt. Chim. Acta, 1957, 1'4, 271.174 P. T. Wagner, L. R. Pollack,and C. G. Donahoe, jun., Analyt. Chem., 1957,29,405.1 7 5 E. Schram and R. Lombaert, Analyt.CJzim. Acta, 1957, 17, 417.176 B. M. Abraham, H. E. Flotow, and R. D. Carlson, Analyt. Chem., 1957,29,1058.177 H. Gamsjager and R. Reichert, 2. analyt. Chem., 1957, 158, 356.178 J. D. Moyer and H. S. Isbell, Analyt. Chem., 1957, 29, 393HASLAM AND SQUIRRELL. 383reducing sugar and measurement of fixed 14C in either formamide or alkalineethyleneglycol.Two papers 179,180 describe the use which has been made of the radio-nuclides 114In and llsIn in the determination of traces of indium in rocksand minerals by neutron-activation analysis. The same radionuclideswere used in the determination of indium in the mineral cylindrite. Thefigures obtained were also confirmed by a method which involved analysisof the decay curve of a sample of cylindrite which had been irradiated withneutrons and also by a method involving y-ray spectrometry.The application of new radiochemical methods to the verification orotherwise of old data is of particular significance in the redetermination ofcertain trace metals in sea-water.HummelIsl has determined gold byneutron irradiation of the sea-water in the Harwell pile. The product istreated with inactive gold. After purification and isolation of the mixtureof inactive gold and the active product lg8Au, the latter is measuredin an end-window Geiger tube. Comparison is made with known goldsoh tions.A procedure requiring the minimum of chemical separation has beendeveloped by Cosgrove and Morrisonls2 for the determination of traceimpurities in tungsten.The use of y-scintillation spectrometry for identific-ation and measurement of the impurities present after neutron activationgives a sensitivity of 0.001 to 1 y for many elements.The important determinations of nickel, cobalt, and copper, oftenpresent in only a few p.p.m. in oceanic rocks, marine sediments, andmeteorites, have been tackled successfully by Smales, Mapper, and W0od.18~After neutron activation of the samples in the Harwell pile and subsequentaddition of nickel, cobalt, and copper carriers, the products are dissolvedand the nickel precipitated as the nickel dimethylglyoxime complex beforeprecipitation of copper as its thionalide derivative. The cobalt in thefiltrate from these precipitations is purified, then precipitated as potassiumcobaltinitrite and counted.The nickel dimethylglyoxime is purified,reprecipitated as nickel dimethylglyoxime, and counted, whilst the copperthionalide is purified and the copper finally precipitated as cuprous thio-cyanate and counted.Cabell and Smales Is4 have determined small amounts of rubidium andczsium in rocks, minerals, and meteorites by a method which again involvesneutron bombardment of the sample. The product is sintered with sodiumperoxide and brought into solution, and carrier added before precipitationof rubidium, caesium, and potassium as cobaltinitrites. The rubidium andcaesium are separated from one another and from potassium by passagethrough a cation-exchange column, and the corresponding rubidium andczesium eluates converted into chloroplatinates, then counted in a conven-tional Geiger f+counting assembly.1 7 ~ A.A. Smales, J. van R. Smit, and H. Irving, Analyst, 1957, 82, 539.180 H. Irving, J. van R. Smit, and (in part) L. Salmon, ibid., p. 549.181 R. W. Hummel, ibid., p. 483.lS2 J. F. Cosgrove and G. H. Morrison, Analyt. Chem., 1957, 29, 1017.183 A. A. Smales, D. Mapper, and A. J. Wood, Analyst, 1957, 82, 75.184 M. J. Cabelland A. A. Smales, ibid., p. 390384 ANALYTICAL CHEMISTRY.APPARATUSA few of the more interesting pieces of apparatus which have beennoted in the course of the year are described below.For use in volumetric analysis a new burette of high accuracy has beendesigned by Smith 185 and tests have shown it to be a great improvementon the ordinary burette.The burette is made of precision-bore tubingand contains a free-moving piston which is graduated with a single orvernier scale. Use of the piston avoids drainage errors and reading theburette is simple and extremely accurate, all meniscus errors being avoided.Automatic stopping devices for the piston can be easily fitted, facilitatingready automatic " zeroing " of the burette or automatic pipetting of a fixedquantity of reagent for routine analysis.An apparatus has been devised by Call l86 for the rapid micro-samplingand determination of vapours particularly halogenated hydrocarbons inair. The air sample is taken through hypodermic tubing by suction andpassed through a heated silica tube, the issuing gases being then passedthrough a reagent solution and the concentration of halogen compoundmeasured colorimetrically.In the case of ethylene &bromide, the reagentfor the bromine produced in the combustion is phenol-red, in a phosphatebuffer at pH 610, which by reaction with bromine produces bromophenol-blue. Once calibrated, the method appears rapid and is particularlyuseful when only small samples are available, e.g., in the case of deter-mination of the concentration of fumigants in the air spaces in soil.On the subject of weighing, a sensitive quartz-beam microbalanceoperating on the principle of the normal gas density balance is preferredby Czanderna and Honig.ls7 With proper temperature control the stabilityis good over long periods of time and the instrument will detect mass changesto a precision of 5 x 10-8 g.with an accuracy of It is said to beextremely rugged in relation to its sensitivity and can be constructed,maintained, and operated without unusual experimental skill.Chemists using chromatographic methods will be interested in a devicedue to B 0 v 6 1 ~ ~ which greatly improves the functioning of the float siphonof automatic fraction collectors when used in the fractional separation ofnon-conducting liquids. A small float in the siphon tube completes anelectrical circuit immediately before the siphon is emptied and causes thecollecting table to rotate. Failures are reported to be less than one in athousand.A simple device for concentrating and eluting spots from chromatogramshas been described by Reith.189 Should a large number of similar spotsbe required to be concentrated, the sections of the papers holding the spotsare pressed together between " Perspex " sheets with a wick in one end ofthe compressed sheets and a pointed, thin, collecting paper at the other.The material is concentrated on the point of the collecting paper by ascendingg.185 I.C . P . Smith, Chem. and Ind., 1957, 1117.186 F. Call, J . AppZ. Chern., 1957, 7 , 210.187 A. W. Czanderna and J. M. Honig, AnaZyt. Chem., 1967, 29, 1206.188 1. Bov6, AnaZyt. Chim. Ada, 1957, 16, 364.180 W. S . Reith, Nature, 1957, 179, 580HASLAM AND SQUIRRELL. 385elution with a solvent which evaporates at the point of the collecting paper.The concentrated spot can then be eluted by a small volume of solvent byreversing the apparatus and using descending elution.The applicationof large amounts of test solution to the paper in chromatographic work hasalways been a problem. A neat device developed by Merz,lgo with whichthe test solution is applied as a uniform streak from a micro-burette drivenby a motor, has largely solved this problem.A useful piece of apparatus has also been designed for the qualitativetransfer of samples to the absorbent column of a gas-liquid chromatographicapparatus. This design by McCreadie and Williams 191 facilitates breakinga capillary containing the weighed sample, at the top of the sealed column,thus avoiding any disturbance of equilibrium. This method is particularlyuseful where the gas inlet pressure is above atmospheric and where the useof an internal standard is not practicable, e.g., when the sample is corrosive,etc.Cummingsand RedfearnIg2 have presented an assembly for the preparation of lowconcentrations of sulphur dioxide in air, for use in the calibration of auto-matic recording instruments.The apparatus, which avoids troubles dueto adsorption and desorption on to the glass walls of the apparatus by usingcontinuously flowing gas streams, could well find application in thepreparation of other gas-air mixtures.A diffusion cell has been described by McKelvey and Hoelscher lg3 alsofor the preparation of very dilute gas mixtures, where the minor componentof the mixture can be liquefied in the laboratory.The liquefied componentof the desired mixture diffuses from a reservoir through a glass tube to themixing chamber through which the diluent gas is passed at constant pressure.For a given cell and liquid component the rate of diffusion is dependentonly on temperature at a constant pressure, Thus the final compositionof the mixture can be quantitatively varied by accurate regulation of thetemperature oi the liquid-component reservoir.A wide-bore dropping-niercury electrode and zinc reference electrodehave been used with success by Briggs et a.l.19.' for the continuous polaro-graphic determination of dissolved oxygen in sewage effluents. Theelectrodes have greater reproducibility in continuous use than the con-ventional dropping-mercury electrode, and the wide-bore electrode has acurrent output about fifteen times greater than the usual type, facilitatingthe use of a more robust pointer-type microammeter, after only a smallamplification.A polarographic cell incorporating a mercury thread electrode has beendesigned and used by Nikelley and Cooke lQ5 for polarographic detectionof metallic ions at concentrations as low as lo4? per ml. by the anodicstripping technique. The method, which involves the deposition of theThe preparation of gas mixtures has received attention.lgO IV. Merz, Mikrochiot. Ada, 1957, 474.l g l S. IV. S. XIcCreadie and A. I;. Williams, J. Appl. Chein., 1957, 7, 47.I g 2 \V. G. Cummings and N. W. Redfearn, Chevn. and I n d . , 1957, 809.lg3 J. M. McKelvey and H. E. HoeIscher, Analyt. Chem., 1957, 29, 123.lg4 R. Bnggs, I?. S. Davies, G. V. Dyke, and G. Knowles, Chetn. and Tnd., 1957, 223.l g 5 J. G. NlkeIly and W. D. Cooke, Analyt. Chem., 1957, 29, 933.REP.-VOL. LIV 386 .A N .I LY TI CAI, CHEMISTRY.metal at the surface of the mercury electrode and then the anodic removalof it under controlled conditions, has been used for the determination ofthe lead and cadmium in spectrographically pure zinc. The calibrationvalues are constant over long periods, and the half-peak potentials agreeclosely with those obtained at a dropping-mercury electrode.which is said to be superiorto the A.S.T.M. lamp used for the determination of sulphur in petroleumdistillates, the latter giving inaccuracies when solutions containing elementalsulphur or some types of volatile sulphur compounds are present. Thisnew lamp gives greater precision at low sulphur contents, uses less sample,and has the advantage of speed, better flame control, and safety.A very simple and easily constructed microscope hot stage has beendescribed by Jennings lg7 for the micro-determination of melting pointsusing only a single crystal. Melting on the hot stage is convenientlyobserved with a polarising microscope or by inserting Polaroid discs in thelight source and eyepiece of a standard microscope.Fluorescence emission spectra of liquids have been measured by usinglaboratory-made accessories in conjunction with a small monochromator,photomultiplier tube, and commercially available a.c. amplifier. Theapparatus of Parker and Barnes lg8 can also be used for the measurementof fluorescence " excitation " spectra. The apparatus has proved to beparticularly useful in studies of fluorescence emission and " excitation "spectra of the two N-phenylnaphthylamines which are used as rubberantioxidants.Automatic spectrophotometric titrations have been convenientlycarried out using the simply designed cell and titration unit of Malmstadtand Vassallo 199 in conjunction with a commercially available secondderivative control unit. A large variety of colour-change titrations canbe carried out with little, if any, modification to the usual titrimetricprocedure.A useful contribution to infrared analysis 2oo is a small evacuable diewhich also serves as the pellet holder and can be used for the qualitativeand quantitative infrared analysis of fraction-milligram size solid samplesin potassium bromide. The die is rectangular and only slightly larger thanthe minimum external dimensions of the sample beam area. The samplemixture with potassium bromide can be prepared by freeze-drying andvibrator grinding in the normal way.A thread wick lamp has been designedJ. HASLAM.D. C. M. SQUIRHELL.Isti W. I<. Battles, ,-liiuZ?t. Ckeni., 1957, 29, 1338.' 9 7 W. G. Jennings, J . Chern. Edztc., 1957, 34, 95.IY* C. A. Parker and W. J. Barnes, A?zalyst, 1957, 82, 606.* 0 9 H. V. Malmstadt and D. A. Vassallo, Analyt. Chipn. Acta, 1957, 16, 465.I. J. Kirkland, Analyf. Chenz., 1957, 29, 1127

ISSN:0365-6217    

DOI:10.1039/AR9575400353

出版商:RSC    

年代:1957

数据来源: RSC

摘要:

INDEX. OF AUTHORS'Abadie, P., 89.Abd Elhafez, F. A., 178.Abe, H., 10.Abe, Y., 17.Abel, E., 50.Abell, D. F., 42.Abelsnes, G., 303.Abraham, B. M., 382.Abraham, E. P., 286, 340,341, 345, 346, 347.Abraham, M. H., 190.Abrahams, C. B., 206.Abrams, R., 339.Acher, R., 281.Ackerman, J., 274.Ackermann, M., 38.Ackermann, W. W., 336.Adams, G. B., 20.Adams, R., 180, 212.Addamiano, A,, 146.Addicott, F. A., 219.Addison, C. C., 110, 144.Adelberg, E. A., 346.Adkins, H., 186.Adler, N., 133.Adriaanse, N., 72.Aebi, A., 226.Agar, J. N., 17.Aggarwal, J. S., 206.Aggarwal, S. L., 53.Agnello, E. J., 264.'Agren, G., 318.Ahluwalia, V. K., 252.Ahrland, S., 122, 145.Aihara, A., 85.Ainscough, J. B., 133, 158.Ainsworth, C., 248.Akehurst, B.D., 213.Alberman, K. B., 213.albers, F. C., 103.Albert, A., 249.Albertson, N. F., 287.Alberty, R. A., 30, 312.Albin, J., 212.Albrecht, R., 187.Alcock, K., 130, 132.Alder, B. J.. 95.Alder, K., 217.Alderton, G., 345, 346.Alderweireldt, F., 214.Aldrich, P. E., 203, 257.Aldrich, R. A., 309.Aldridge, W. N., 286, 318,Alekandrova, G. V., 224.372.Alexander, G. J., 276, 3.50.Alexander, P., 57, 69.Alfieri, R., 25.Alhuwalia, J. S., 399.A41iprandi, B., 70.Allen, A. O., 64.-Allen, C. F., 2Qb.Allen, D. S., 177.Allen, P. W., 56, 243.Allen, T. L., 82.Allinger, J., 160, 178.Allinger, N. J., 214.Allport, D. C., 230.Allred, A. L., 15.Allsopp, C. B., 70.Alonzo, N., 208.Altman, K. I., 325.Amamiya, A., 69.Albroz, L., 59.Amdur, B.H., 203.Amell, A. R., 50.Amiard, G., 264, 272, 278,287, 289, 291.Amiel, S., 138.Amiel, Y., 198.Amis, E. S., 43.Ammar, I. A., 26.Ananchenko, S. N., 224,Anbar, M., 18.Anchel, M., 197.An Cu, N., 258.Anderson, A. G., 236.Anderson, D. H., 14.Anderson, E. P., 330.Anderson, G. W., 287.Anderson, H. H., 108.Anderson, H. J., 241.Anderson, L., 316, 318.Anderson, I,. B., 108.Anderson, L. C., 67, 167.Anderson, P., 178.Anderson, R. C., 80.Anderson, W., 14.Anderson, W. A., 13, 110.Anet, R., 261.Anfinsen, C. B., 280, 286.Ang, F., 63.Angoletta, M., 142.Angyal, S. J., 172,250, 293.Anliker, R., 210.Anner, G., 275.Anslow, W. P., 331.Anson, F. C., 362.Antia, N. J., 301.Appel, H. H., 220.387NAMESArcamone, F., 394.Archer, S., 174.Archer, W., 247.Arcus, C.Id., 53.Ardon, M., 49.Arens, J. F., 244, 288.Arganbright, R. P., 177.Argoudelis, A. D., 305.Arigoni, D., 215, 217, 225,Armarego, W. L. F., 151.Armstrong, A. M., 46,Arnold, H. B., 267.Arnold, J. T., 12.Arnold, J. W., 33, 88.Arnold, W., 258.Arnstein, H. R. V., 340,Aronoff, S., 318.Arvidson, H., 330.Ashby, C. E., 54.Ashby, E. C., 101, 193.Ashmore, P. G., 34.Ashton, J. B., 230.Ashurst, I<. G., 46.Ashwell, G., 300.Ashworth, P. J., 300.Asinger, F., 242, 246.Asmussen, R. W., 140.Asperger, S., 164.Aspinall, G. O., 293, 398,Asprey, L. P., 138.Astill, B. D., 251.Astrom, B., 138.Aten, A. W. H., 48, 116.Athavale, V. T., 357.Atkinson, B., 39.Atkinson, V.A., 39.Atoji, M., 98, 100.Atterling, H., 138.Augood, D. R., 168.Aurivillius, K., 146.Ausloos, P., 37.Austen, D. E. G., 11.Austin, (7. M., 373.Avram, M., 234, 235.Axilrod, B. M., 86.Axworthy, A. E., 33.Ayad, K. N., 169.Ayer, W. A., 262.Aynsley, E. E., 118, 142.Ayres, G. H., 140.Azarnoff, D. L., 275.226, 227.146.342, 343, 345, 349.349388 IBabicky, A., 70.Bachelor, 1;. IT'., 242.Bachman, G. B., 100, 234,Bachmann, G. B., 195.Back, RI. H., 64.Backhouse, It., 140.Bacon, J. S. D., 325.Baddeley, G., 153, 156, 162.Rader, A. R., 178.Badger, G. M., 181, 229.Badger, S. J., 330.Baddiley, J., 300, 3G3, 335,Bachli, E., 257.Baenziger, N. C., 130.Baer, H. H., 305.Baes, C. F., 45.Bagdasaryan, Kh.S., 66,Bagguley, D. M. S., 9.Baghurst, H. C., 374.Bagnall, K. TV., 118.Bailar, J. C., 51.Bailey, A. S., 205, 206,Bailey, J. L., 280.Bailey, N., 134.Bailey, I'. S., 230.Bailey, W. J., 187, 214.Baines, C. B., 366.Bainova, M. S., 257.Bains, G. S., 377.Baird, R., 160, 161, 232.Bak, B., 188.Bakacs-PolgAr, E., 368.Baker, E. B., 12.Baker, F. B., 47.Baker, H. T., 243.Raker, J. W., 150.Baker, W., 228, 236, 239.Bakes, M., 80.Bakhuis, J. A., 276.Balashova, N. A., 20.Halazs, E. A., 70.Baldwin, R. It., 41.Balint, A. E., 192, 194.Eallard, D. G. H., 58.Ballantine, D. S., 69.Ballantine, J . A., 248.Ballhausen, C. J., 93, 128.Ballinger, P., 160, 162.Ballou, C., 300.Ballou, C. E., 316.Balon, A. D.J., 187.Bamford, C. H., 56,58, 292.Hanerjea, D., 5.2, 123.Banerji, J. C., 173.Ranfield, J. E., 246.Banks, C. V., 372.Bannister, B., 176, 274.Barakat, M. F., 365.Baram, 0. M., 117.Baranay, R., 80.Barbaras, G. K., 78.Barber, E. J., 119.244.336.167, 168.228.DEX OF AUTHORS' NAMES.Bardone-Guademar, I?., 200.Bardos, T. J., 250.Bardwell, J., 66.Barker, G. R., 292, 294.Barker, H. A., 312, 333.Barker, H. C., 167.Barkley, L. B., 275.Barltmp, J. A., 222, 252,Barnafi, L., 283.Rarnard, J. A., 39.Barnes, F. W., 329.Barnes, F. W., jun., 317.Barnes, R. G., 16, 17, 103.Barnes, R. K., 212.Barnes, W. J., 386.Barnett, AT. K., 134.Barney, J. E., jun., 374.Barnholdt, R., 203.Barnwell, J. L., 302.Barr, E. W., 157.Barr, N.F., 64.Barrett, C. B., 248.Barrett, J., 53.Barrett, S. O., 197.Barry, G. T., 319.Barry, V. C., 249.Barry, W. T., 40.Bartels-Keith, J . R., 213.Bartlett, M. F., 289.Bartlett, N., 117, 142.Bartlett, P. D., 160, 209.Barton, D. H. R., 170, 173,174, 217, 218, 219, 225,260, 265, 267, 269.359.Barton, G. M., 237.Barton, R. J., 131.Bartos, J., 289.Bartsch, W., 243.Bartz, Q. R., 336.Baruch, J., 91.Basolo, F., 51, 53, 122, 123.Bassett, J. Y., jun., 139.Batsanova, L. R., 96.Battersby, A. R., 256, 257,Battles, W. R., 386.Baudler, M., 11 1.Bauer, S. H., 35, 78.Bauman, W., 251.Baumeister, L., 325.Baumgarte, U., 165.Baumgartner, W., 226.Baur, W. H., 94.Bawn, C. E. H., 46, 50, 53.Baxendale, J . H., 48, 53,Beachall, H.C., 118.Beard, C., 169.Beattie, I. R., 107, 110.Beaven, G. H., 148.Becher, H. J., 101.Beck, S. D., 248.Beck, T. R., 18.Becke-Goehring, M., 112,347.140.113, 141.Becker, E., 95.Becker, E. I., 215.Becker, M., 20.Becker, W. E., 45.Beckett, A. H., 178, 187.Beckett, M. C., 150, 153.Beckmann, R., 251.Beckwith, A. L. J., 169.Bedford, F. C., 132.Bedoukian, P. Z., 195.Beecken, H., 251.Beer, R. J. S., 248.Beereboom, J. J., 225.Beerthuis, R. K., 368.Beglinger, U., 292.Behrens, H., 124.Behrens, 0. K., 280, 340,Behrends, J., 358.Behringer, H., 242.Beitner, A., 260.Bejar, O., 257.Bekesy, N., 366.Bell, I., 163, 198.Bell, K. M., 41.Bell, M. R., 174, 347.Bell, P. H., 282.Bell, S. W., 110.Bell, T.N., 34.Belton, J. G., 249.Beltrami, R. T., 108.Benard, J., 121, 122.Bendas, H., 266.Bender, M. L., 162, 243,Benedict, R. G., 345.Benesch, R., 278.Benesch, R. E., 278.Benjamin, B. M., 185.Benkeser, R. A., 154, 193.Benn, W. R., 272.Bennett, G. E., 199.Bennett, L. L., 336.Bennett, L. L., jun., 243.Bennett, J. E., 10.Bennett, W., 68.Benoit, H., 54.Bensasson, R., 68.Bensey, F. N., 119, 120.Bensley, B., 162.Benson, G. C., 91.Renson, R. E., 185, 238.Benson, S. W., 33, 77.Bentley, M., 339.Bentley, R., 295, 309, 310,311, 333, 349.Beranek, J., 242.Berchtold, R., 208.Berg, E. W., 358.Berg, P., 313.Bergel, F., 225.Berger, A., 187.Berger, H., 262.Berger, J., 249.Berger, S. B., 44.Berger, W., 371.341.310INDEX OF AUTHORS’ NAMES.389Berghausen, 1’. E., 86.Bergmann, E. D., 367.Bergmann, W., 269.Bergstrom, S., 330.Berhnard, C., 236.Beringer, F. M., 55.Berkengeim, T. I., 47.Berkenhoff, H. O., 107.Berkholetova, G. P., 224.Berkowitz, J., 82, 135.Berkowtich, J ., 69.Berky, J., 342.Berliner, E., 149, 150, 153,Bernard, R., 91.Bernas, A., 68.Berneis, H. L., 78.Bernfeld, P., 279.Bernstein, H. J., 14, 184,Bernstein, R. B., 39, 146.Berry, K. S., 144.Berridge, N. J., 345.Bersohn, I<., 10, 16.Berson, J. A., 167, 179.Berth, P., 256.Bertho, A., 251.Berthold, R., 117.Bertolacini, R. J., 374.Bertrand, J. A., 124.Bessant, K. H. C., 186.Best, G. F., 137.Bestmann, H. J., 196.Beton, J. L., 214.Bevan, C.W. L., 157.Bevan, T. H., 207, 208.Bever, M. B., 81.Revington, J. C., 56, 57,Beynon, K. I., 165.Beyer, H., 242, 246.Beyerman, H. C., 256.Bhar, B. N., 50.Bhatia, D. S., 377.Bhattacharya, P. R., 58.Bhattacharyya, B. K., 267,Bhattacharyya, S. C., 226,Bianchi, D., 111.Bianchi, J. P., 5G.Biberacher, G., 112.Bickel, A. F., 170, 189, 232.Bickelhaupt, F., 233.Bieber, I. T., 235.Biekert, E., 251.Biemann, K., 244.Bier, A., 79.Biggs, A. I., 377.Bijl, D., 165.Bilbo, A. J., 113.Billeter, J. R., 275.Billica, EI. R., 186.Billman, J. H., 188, 196.Billmeyer, F. W., jun., 54.Billy, C., 94.161.293.168.274.369.Bindschadler, E., 130.Binks, J. II., 155.Binlts, R., 257.Birch, A. J., 176, 203, 204,208, 213, 230, 231, 249,253, 254, 348, 350.Bird, G.R., 8.Bird, H. L., 280.Birkhofer, L., 396.Birkofer, L., 211, 241.Birrell, R. N., 37.Birss, F. W., 38.Biserte, G., 285.Bisque, R. E., 372.Bister, W., 305.Bitler, B. A., 351.Bittniann, S., 61.Bizioli, F., 304.Bjellerup, L., 77.Bjerrum, N., 87.Blacet, 1;. E., 40.Black, A. H., 50.Black, S., 346.Blackburn, 1’. E., 82.BlAha, K., 256.Blair, J. McD., 228.Blakley, 13. L., 249.Blamer, G., 66.Blanchard, L. B., 33.Blanquet, P., 3‘73.Blasius, E., 365.Blau, J. A., 102.Blears, M. J., 298.Blickenstaff, R. T., 270.Blix, F. G., 320.Blix, G., 320, 322, 325,33loch, F., 44, 240.Bloch, K., 203, 224, 276,Blommers, E. A., 150.Blomquist, A. T., 56, 171,183, 214, 230, 235.Bloom, B., 317.Bloom, B.M., 274.Blouin, F. A., 173, 292.Blout, E. R., 58.Blume, D., 136.Blumenthal, D. C., 146.Boaz, H. E., 258.Boberg, F., 241.Bobtelsky, &I., 371, 372.Boekelheide, V., 248, 251.Bockris, J . O’M., 19 ,20, 26,Bodhszky, R., 288.Bode, H., 24, 357.Bodea, C., 203.Boehm, H. P., 105.Bohm, P., 325.Boehm, R., 226.Bottcher, C. J. V., 84.Bottcher, R., 129.Bogdanov, G. A., 47.Boggianni, B. G., 248.Bogoch, S., 208, 325.328.310, 315.28.Bogoniolova, N. F., 61.Bohlmann, F., 184, 197,198, 199, 200, 243, 255,256.Bohme, H., 101.Bohmfalk, E., 74.Boisselle, A. P., 248.Boissonnas, K. A., 289,291.Boit, H.-G., 260.Bokii, G. B., 123.Boll, E., 101.Boller, A., 242.Boman, H. G., 279.Bonde, E. K., 219.Bondhus, F. J., 149, 150.Bondi, A., 83.Bone, S.J., 24.Bonhoeffer, K. F., 26.Bonner, N. A., 42.Bonner, T. G., 156.Bonner, W. A., 33, 186.Bonner, W. H., 78, 150,Booth, E., 380.Bor, G., 82.Borchardt, H. J., 42.Bordwell, F. G., 160, 162,Borenfreund, E., 302.Borgers, R., 248.Borisov, A. E., 169.Borisova, T., 28.Bornong, B., 46.Bornstein, J., 248.Borsche, W., 227.Bortner, T. E., 66.Bortnick, N. M., 200.Bortnick, R. M., 240.Borzenkova, M. P., 96.Boschan, K., 160.Bosshard, H., 217, 218.Boston, A., 184, 187.Bostrup, O., 140.Boswell, G. A., 276.Bothner-By, A. A., 15.Bothner-By, C. T., 70.Botimer, L. IN., 247.Bottini, A., 208.Bottini, A. T., 158, 233.Bouby, L., 68.Bouissieres, G., 134.Boult, E. H., 23.Bourdon, J., 189.Bourne, E.J., 106.Bovarnick, M., 348.Bov6, J., 384.Bovey, F. A., 57, 69.Bowden, S. T., 165.Bower, J. D., 248.Bowers, A., 263.Bowers, K. D., 9.Bowman, R. E., 188.Bowyer, W. J., 254.Boyars, C., 89.Boyd, G. V., 252.Boyd, R. H., 214.161.168, 177390 INDEX OF AUTHORS' NAMES.Hoyer, J . H., 244, 248.Boyer, P. D., 300, 312, 313,Boyes, A. G., 54.Boysen, M., 68.Brack, A., 260.Brackett, E. B., 7.Brackett, T. E., 82, 116.Brade, H., 181, 153.Bradley, D. C., 108, 130,131, 136, 137.Bradley, W., 234.Bradlow, H. L., 270.Bradsher, C. K., 262.Brady, G. W., 16.Brady, J . D., 150, 161.Brauninger, G., 243.Bragg, P. D., 293.Braithwaite, G. D., 203.Braun, G. A., 320.Braun, R. A., 196.Braunholtz, J.T., 251.Braunstein, A. E., 317.Bray, P. J., 16, 17, 103.Brdicka, R., 70.Bream, J . B., 178, 266.Bredenberg, J. B., 222.Bredereck, H., 245.Breiter, M., 18, 20.Brendel, G., 125.Brenner, J. E., 217.Brenner, M., 292.Breslow, D. S., 62, 102.Breslow, R., 212, 234.Breu, R., 126.Brewer, L., 81, 107.Brewster, J. H., 197.Brice, C., 296.Bridgwater, R. J., 270.Brieux, J. A. L., 150.Briggs, G. W. D., 23, 25.Briggs, I,. H., 273.Briggs, R., 385.Brill, R., 87.Brimacombe, J. S., 293.Grimm, E. O., 80.Briner, E., 72.Britt, R. D., jun., 354.Broadhead, G. D., 238.Brockerhoff, H., 205.Brockmann, H., 210, 230,231, 286.Urodersen, K., 105, 146.Brody, H., 60.Rromer, W. W., 280.Brook, J. H. T., 49, 170.Brook, P. R., 245.Brooke, D.G., 206.Brooke, M. S., 339.Brookes, P., 243, 346.Brooks, C. J. W., 220.Brooks, J. W., 180.Brooks, P. R., 259.Broome, J., 263.Brossmer, R., 305,320, 323.Brot, C., 86, 87.314, 315.Brotherton, T., 306.Brotherton, T. K., 195,Brown, B. K., 187, 263.Brown, C. P., 59.Brown, D., 302.Brown, D. J., 248.Brown, D. W., 57, 69.Brown, E. V., 244.Brown, H. C., 52, 78, 98,150, 153, 155, 156, 161,162, 163, 188, 214.233.Brown, R. A., 282.Brown, R. F. C., 241.Brown, T. L., 192.Brown, W. G., 149.Brownell, H. H., 367.Brubaker, C. H., 42.Bruce, C. R., 44.Bruckner, V., 291, 292.Bruderer, H., 217.Bruckner, K., 270.Bruice, T. C., 243.Brunauer, S., 28.Brune, R., 196.Brunner, R., 260.Brunold, A,, 108.Brutcher, F.V., 171.Bryant, F. J., 380.Bryant, W. M. D., 55.Bryce, W. A. J., 57.Bublitz, D. E., 209.Bucek, W., 368.Buchanan, J. B., 346.Buchanan, J. G., 300, 303,Buchanan, J. M., 333-338.Buchanan, T. J., 87.Buckler, S. A., 187, 190.Buckley, R. P., 168, 169,Buckmaster, A. A., 9.Budenstein, Z., 31 1.Bueche, F., 53.Buchi, G., 216, 217, 220,Buchi, J., 226.Burger, K., 379.Buhler, D., 310.Buisman, J. A. K., 273.Buist, G. J., 295.Bullock, E., 250.Bullock, M. W., 207, 243.Bullock, J. D., 197, 230.Bumgardner, C. L., 182.Bunbury, D. L., 166.Bundschuk, W., 256.Bunnett, J. F., 157, 158,Hunton, C. A., 45, 150, 160,Burbank, R. D., 119,Burd, L. W., 12.Burford, R. R., 171, 214.Burg, A. B., 99, 113.336.178.244.195, 233.295.120.Burgstahler, A.CV., 223,Burkett, H., 154.Burkhill, P. I., 227.Burn, D., 222, 272.Burnett, I;. M., 326.Burns, J. F., 81.Burr, J. G., 67.Burroughs. L. F., 276.Burstein, S., 225.Burt, R., 41.Burton, H., 156.Burton, M., 67.Burtt, B. P., 66.Burwasser, H. B., 35, 67.Burwell, R. L., 178.Buss, J. H., 77.Butenandt, A., 207, 250,269.251.277.Buu-Ho~, Ng. Ph., . 196,Bye, G. C., 157.Bywater, S., 55, 59.Cabell, M. J., 383.Cabrera, N., 21.Cacace, F., 70.Cacciola, A. R., 282.Cadiot, P., 199, 200.Cady, G. H., 13, 106, 117,Caglioti, L., 225.Cahn, R. S., 179.Caillon, P., 89.Cain, C. E., 238.Cainelli, G., 226.Cairns, J. L., 235.Cairns, T. L., 204, 209,Caldas, A,, 355.Calderazzo, F., 124.Caldin, E.F., 158.Caldwell, E. V., 108.Caldwell, W. C., 82.Caliezi, A., 223.Call, F., 384.Callis, C. F., 13, 110.Callis, J. F., 13.Callomon, J. H., 7, 31.Calvert, J. G., 31, 40.Calvin, hl., 10, 11, J28,165, 185, 300.Cameron, M. D., 199.Camerino, B., 267.Campbell, C. E., 31.Campbell, D. R., 45.Campbell, G. W., 98.Campbell, T. W., 240.Campbell, W. A., 118, 142.Campi, E., 53.Campos-Neves, A. d a S.,Cannell, L. G., 155.Cantoni, G. L., 315.Capon, B., 157.Capps, R. H., 82.119.235.265INDEX OF AUTHORS NAMES. 391Caputo, A., 71.Caputto, E., 325.Carboni, R. A., 209, 235.Care, R. A., 79.Carini, F. F., 79.Carlon, F. E., 272.Carlson, E. H., 10.Carlson, R. D., 382.Carlsson, I. B., 146.Carruthers, W., 252.Carsiotis, M., 313.Carson, A.S., 73.Carson, E. M., 73.Carson, W. N., jun., 363.Carss, B., 300, 303.Carter, C. E., 339.Carter, H. E., 340, 348.Carter, M. E., 298.Casabella, P. A., 16, 17,Case, J. R., 228.Caseli, L., 77.Casinovi, C. G., 252.Cason, J., 205.Cass, R. C., 148.Casselman, A. A., 367.Castellion, G. A., 38.Castells, J., 266.Caswell, L. R., 196.Catchpole, A. G., 163.Cates, V. E., 354.Cava, M. P., 235.Cavill, G. W. K., 215, 250.Cekan, Z., 220.Cenci, H. J., 171.Cerfontain, H., 161.Chackraburtty, D. M., 100.Chadha, R. N., 56.Chadwick, J., 162.Chaigneau, M., 355.Chain, E., 341.Chakravarti, B. N., 136.Chalk, A. J., 47.Challenger, F., 346.Challis, B. C., 297.Challis, H. J. G., 359.Chaman, Ye.S., 213.Chamberlain, N., 337.Chamberlin, E. M., 269.Chan, W. R., 226.Chang, F. C., 270.Chang, J., 67.Chang, W.? 30.Cliannen, E. W., 91.Chapiro, A., 66, 68.Chapman, D., 207.Chapman, F. W., jun., 376.Chapman, N. B., 157.Charalampous, F. D., 337.Charbonni&re, R., 89.Chargaff, E., 325.Charles, R. G., 79.Charlesby, A., 57, 69, 70.Charlton, F. E., 379.Charlton, J. C., 162.Charney, W., 272.103.Chatt, J., 122, 127, 142,Chatterjee, A. K., 130, 136.Chau, J . Y . H., 85.Chaudhuri, N-K., 245.Chauvette, K. R., 210.Chemerda, J. M., 269.Chen, M. C., 33.Chen, W. K. W., 69.Chernick, C. L., 73, 77, 79.Chernova, A. I., 65.Chernyayev, I. I., 122.Chernykh, V. I., 96.Chesnut, D. B., 11.Chiavarelli, S., 252.Chicoisne, A., 207.Chien, J.C. W., 33.Chi-Hsiang MJong, 145.Child, R. G., 282.Chiltz, G., 38.Chirnside, R. C., 374.Chiurdoglu, G., 218.Chodkeiwicz, W., 199, 200.Cholnoky, L., 202.Chopard-dit- Jean, L. H.,Chouiken, N. I., 213.Chow, S. W., 218.Christensen, B. E., 208.Christensen, D., 8.Christensen, P. K., 198.Christian, C. G., 178, 228.Christiansen, J. A., 19.Christie, B. J., 229.Chupka, W. A., 82, 135.Ciamician, G., 217.Cini, R., 141.Ciotti, C. J., 197.Ciotti, M. AT., 308.Cipera, J. D. T., 296.Claassen, H. H., 142.Clar, E., 229, 230.Clark, H. C., 132, 140.Clark, R. E. D., 355, 370.Clark, V. M., 241.Clarke, A. J., 200.Clarke, E., 311.Clarke, E. M., 81.Clarke, H. B., 74.Clarke, K., 248.Clarke, K. J., 329.Clarke, R.W., 68.Clark-Lewis, J . W., 853,Clasper, M., 368.Clauson-Kaas, N., 241.Clauss, A., 105.Clay, P. G., 67.Clayton, D. W., 261.Clayton, J. M., 58, 156.Clayton, R. B., 171, 276.Clegg, R. E., 71.Cleland, M., 204.Clement, R. A., 274.Clemo, G., 255.Clezy, P. S., 250.143, 145.201.291.Clifford, A. F., 119.Clippinger, E., 159.Closson, R. D., 125, 129,Clubb, M. E., 343.Cluley, H. J., 374.Coats, F. H., 80.Cobble, J. W., 138.Cochran, J. C., 157.Cochran, W., 144.Cocker, J. D., 221, 222.Cocker, W., 217.Codell, M., 381.Codrington, R. S., 10.Coffield, T. H., 125, 129,Coffman, D. D., 209, 235.Cohen, A. D., 15.Cohen, C., 184.Cohen, D., 42, 43.Cohen, J. A., 318.Cohen, L. A., 185.Cohen, L. H., 339.Cohen, P.P., 331.Cohen, S. G., 166, 167.Cohen, S. S., 300, 330.Cohen, T., 260.Cohn, Xf., 309, 311, 312,Cole, A. R. H., 184, 226.Cole, K. S., 86.Cole, R. D., 283.Cole, R. H., 86, 88.Cole, S., 68.Cole, T., 12.Coleby, B., 70.Colingsworih, D. R., 340.Collie, J. N., 350.Collier, H. 0. J., 249.Collin, J., 38, 800.Collins, C. J., 186.Collinson, E., 50,55,64,68.Collongues, R., 121.Collran, R. L., 295.Collyns, B. G., 57, 69.Colom, F., 20.Colonge, J., 199.Colowick, S. P., 308, 313.Colton, F., 272.Combe, A., 37.Comyns, A. E., 128, 151.Conalty, M. L., 249.Concilio, C. B., 115.Condon, I?. E., 153.Conia, J.-M., 211, 213.Conlon, L. E., 200.Conn, E. E., 308.Conn, J. B., 149.Conrad, A. L., 365.Conradi, J.J., 11.Conroy, H., 226, 259.Conroy, L. E., 135.Convery, R. J., 168, 196.Conway, B. E., 28.Cook, A. H., 214.Cook, C. D., 189.239.239.314392 INDEX OF AUTHORS NAMES.Cook, H. F., 87.Cook, R. E., 58.Cooke, W. D., 385.Cookson, R. C., 170, 173,175, 185, 215, 231.Coombes, J. D., 59, 60.Cooper, C., 330.Cooper, G. D., 160, 162.Cooper, H. C., 353.Coops, J., 72.Cope, A. C., 160, 182, 195.Copenhaver, J. H., 311.Coppens, P., 48, 116.Coppinger, G. M., 48, 165,Coppock, W. H., 197.Corbaz, R., 249.Corbellini, A., 270.Corbett, J. D., 103.Corbett, W. N., 297, 298.Corey, E. G., 187.Corey, E. J., 171, 177, 184,318, 224, 239.Cori, C. F., 316.Cori, G. T., 312.Corio, P. L., 15, 156.Corlateanu, P., 61.Cornforth, J.W., 203, 208,275, 276, 319.Cornforth, R. H., 203.Cornwell, C. D., 17.Corrodi, H., 209.Corse, J., 160.Corse, J. W., 340, 341.Cortier, J., 157.Cosgrove, J . F., 383.Costain, C. C., 7.Cotton, F. A, 15, 74, 12.5.Coughlin, J. P., 80.Coulson, E. A., 244.Coutts, R. T., 230.Cowan, M., 7.Cowles, E. J., 236.Cox, U., 140.Cox, H. C., 209, 261.Cox, H. R., 282.Cox, J. S. G., 224.Cox, S., 267.Craig, J . T., 341.Craig, L. C., 286, 346, 347.Cram, D. J., 158, 160, 178,Cramer, F., 179.Crawford, B., 33.Crawford, R. J., 232.Crawhall, J. C., 345.Cremer, J. E., 372.Cremieu, A., 83.Cremlyn, R. J. W., 185,Crespi, G., 63.Criegee, R., 213. 235, 249.Cristol, S. J., 177.Cromartie, R. I. T., 248.Crombie, L., 198, 199, 200,205, 207, 210, 213.232.185.263.Cromer, D.T., 144.Crossley, A., 207.Crowley, K., 217.Crumpton, M. J., 305.Csanyi, L. J., 47.Cserr, R., 192.Cullis, C. F., 41.Cummings, Mr. G., 385.Cummins, E. G., 262.Cunningham, B. B., 80,Cunningham, J., 68.Cuomo, S., 83.Curby, R. J., 185, 239.Curphey, E. G., 60.Curran, C., 101, 123.Curran, G. L., 275.Curtin, D. Y., 185, 232.Curtis, A. J., 86.Curtis, G. C., 137.Curtis, M. L., 134.Curtis, 0. E., jun., 213.Cuscurida, M., 187.Cutler, D., 12.Cutts. N. s., 337.Cvetanovic, R. J., 40.Czaloun, A., 117.Czanderna, A. W., 384.Czekay, A., 365.Daane, A. H., 131.d’Adamo, A. F., jun., 10.Dahl, L. F., 125.Dahmen, E. A. &I. I?., 364.Dahmen, H., 106.Dailey, B. P., 15, 156.Daines, M.E., 208, 319.Dainton, F. S., 31, 38, 48,50, 55, 57, 64, 67, 68, 77,81.138.Dale, J. W., 115.Dale, W. M., 70.Dalgliesh, C. E., 347.Dallwigk, E., 72.Danby, C. J., 38.Dandegaonlter, S. H., 102.Daniel, S. S., 140.Daniels, F., 39, 42.Daniels, M., 63, 64, 70.Danielsson, H., 276.Danilova, S. N., 296.Dankert, G., 230.Dankner, D., 178, 200.Danneberg, P., 245.Dannhauser, W., 86.Dannley, R. L., 195.Danon, J., 118.Danusso, F., 53, 63.Darling, S. D., 274.Darwent, B. de R., 41.Danvish, D., 164.Dasgupta, S., 88, 206.Datta, S. P., 74.Dauben, H. J.. 236.Dauben, W. G., 70, 160,215, 270, 272, 276.Dautrevaux, M., 285.David, C. F., jun., 9.Davidson, A. W., 26, 145.Davidson, D., 257.Davidson, D. W., 86, 88.Davidson, F.G., 76.Davidson, G. C., 256, 257.Davidson, N., 34, 47.Davie, E. W., 314.Davies, A. C., 207.Davies, A. G., 190, 197.Davies, D. A. L., 304.Davies, D. S., 170, 282.Davies, F. S., 385.Davies, G. L., 167.Davies, J. A., 31.Davies, J. V., 70.Davies, M., 79, 85, 282.Davies, M. C., 282.Davies, N. R., 145.Davies, W., 229, 246.Davis, S. B., 282.Davis, T. W., 68.Davison, W. H. T., 57, 59,Dawes, J. W., 143.Dawson, R. M. C., 208.Day, A. R., 50.Day, J. H., 72.Day, &I. J., 65.Dean, F. BI., 253, 254.Dean, J., 37.Dean, W. R., 52.Deane, K. R., 276.Dearing, G. G., 370.de Boer, E., 10, 11.de Brouchhre, L., YO.de Brun, C. H., 309.Debye, I>., 84.De Flines, J., 341, 345.DeFord, D. D., 358, 364.Degener, E., 109.de Grandchamp-Chaudun,De Jonge, J., 156.Delahay, P., 17, 19, 27.de la Mare, P.B. D., 149,150, 152, 153, 154, 160,161, 162, 164.Dell, P. A., 146.Delluva, A. M., 330, 333.De Long, C. W., 342, 343.Del Re, G., 141.de Maeyer, L., 51.Demain, A. L., 340, 343.de Maine, P. A. D., 148.de Mayo, P., 217, 218, 219,de Modica, G., 237.Den Boer, D. H. W., 348.Dennery, J. M., 249.Denney, D. B., 160.Dennison, D. M., 9.Denny, D. J., 86.Denny, J. D., 86.Deno, N. C., 151.67, 69.A., 297.262INDEX OF AUTHOIiS NAMES. 393de Paulet, A. C., 268.De Puy, C. H., 164, 213,Derbyshire, D. H., 152.Dermer, 0. C., 168.de Roos, A. M., 48, 116.Desreux, V., 69.Dess, H. M., 114.Dessy, R. E., 212.DeTar, D. F., 166, 234.Deuel, P.G., 219.de Vivar, A. R., 268.Dewald, J . F., 21, 22.DeWalt, H. A., 274.Dewar, M. J. S., 151, 153,Dewey, V. C., 330.Dewhurst, H. X., 67.DeWolfe, R. H., 163.Diacont, K., 227.Diaper, J . , 8 1.Diara, A., 222.Diassi, P. A,, 255.Dibbs, H. P., 23.Dibeler, V. H., 119.Dickens, J. E., 122.Dickerman, S. C., 169.Dickerson, R. E., 97.Dickman, S. R., 312.Diedrich, D. F., 316.Diehl, P., 14.Dieringer, F., 85.Diesing, A. C., 188.Di Giacomo, A., 88.Dignam, M. J., 38.Dijkstra, R., 156.Diller, E. R., 280.Dimroth, K., 165, 189, 228,232, 243, 252.Dimroth, O., 249.Dingledy, D. P., 82.Dintzis, H. M., 278.Dinu, D., 235.Dirkse, T. P., 26.Dische, Z., 302.Ditcham, J. B., 244.Dittmann, O., 104.Dituri, F., 203.Dixon, B.E., 374.Dixon, J. S., 283.Djerassi, C., 183, 210, 220,221, 225, 230, 256, 262,263, 266.237.161, 248.Dobbert, N. N., 317.Dobe, K. A., 82.Dobriner, S., 175.Dodd, R. E., 37, 142.Dodson, R. M., 272.Dodson, R. W., 42, 43.Dodson, V. H., 50.Doplte, W., 260.Doering, W. von E., 75,149, 237, 309.Doerschuk, A. P., 351.Doherty, D. G., 310.Doisy, E. A., 270.Doisy, E. A., jun., 270.Dolby, L. J., 149.Dole, M., 57, 69, 70.Dolejs, L., 218, 219, 220.Domash, L., 163.Donahoe, C. G., jun., 382.Dondes, S., 66.Donovan, F. W., 220.Doppler, G., 360.Dorfman, R. I., 309, 310.Dornow, A., 243.Dorsey, W. S., 178, 228.Doty, P., 58, 184.Doudoroff, M., 312.Douglass, R. M., 134.Douslin, D. R., 83.Down, J.L., 95, 189.Downey, P. F., 346.Doyle, F. P., 248.Doyle, L. C., 40.Dozinel, C. M., 373.Drago, R. S., 135.Dreiding, A. S., 232.Drell, W., 332.Drew, R. M., 325.Driscoll, W. J., 130.Drossler, H. G., 165.Dryden, J . S., 84, 88.Drysdale, G. R., 309.Drysdale, J. J., 13, 184.Dubovitshii, F. I., 35.Ducret, L., 372.Dudley, F. B., 13, 117.Duke, F. R., 43, 46.Dulmage, W. J., 63.Dulou, R., 207.Dumitrescu, N., 62.Dummer, G., 256.Duncanson, L. A., 143.Dunham, K. R., 63.Dunitz, J. D., 94.Dunn, T. M., 154.Dunning, E., 244.Dunstan, W. J., 225.Dupont, G., 207.Durand-Dran, R., 167.Durell, J., 315.Duschinsky, R., 245.Dusoleil, S., 38.Dusza, J. P., 269.Dutcher, J. D., 305.Dutler, H., 218.Dutta, B. N., 204.Dutta, P.C., 224.Dutz, R., 211, 241.Duus, H. C., 76.du Vigneaud, V., 289,Duyckaerts, G., 364.Dvonch, W., 345.Dvornik, D., 260.Dwyer, F. P., 124.Dyke, G. V., 385.Dyne, P. J., 66.Dzombak, W. C., 74.Dzurus, N. L., 104.291.Eaborn, C., 150, 154.Eade, R. A., 253.Eakin, R. E., 336.Eardley, S., 248.Earnshaw, A., 95.Easterbrook, W. C., 358.Eastham, A. M., 68, 59.Eastham, J. F., 274.Eaton, D. C., 178, 266.Eaves, D. E., 57.Ebeid, F. B., 41.Eberhagen, D., 2C5.Eberle, A. R., 373.Ebersberger, J., 194, 232.Ebert, M., 71.Eby, C . J., 244.Ecke, G. G., 194, 232.Eckert, G., 357.Eckhart, E., 296.Economy, J., 242.Eddy, L. P., 155.Edgecombe, F. H. C., 33.Edman, P., 31, 279.Edmison, M. T., 168.Edmonds, M., 330.Edson, N. L., 332.Edward, D.W., 249.Edward, J. T., 217, 296.Edwards, J. D., 101, 240.Edwards, J. O., 45.Edwards, J . P., 341.Edwards, J. W., 111, 359.Edwards, 0. E., 260.Edwards, T. P., 257.Eenshuistra, J., 256.Egerton, (Sir) A, 41.Eggerer, H., 204.Eggertsen, F. T., 376.Eggleston, L. V., 331.Eglinton, G., 199, 234.Egorov, Y. P., 213.Ehrensvard, G., 330.Ehrensvard, G. C. H., 287.Ehrlich, P., 97.Eick, H. A., 130.Eigen, M., 51.Eigner, E. A,, 282.Eirich, F., 60.Eisch, J., 239.Eisenberg, M. A., 313.Eisenbraun, E. J., 215.Eisenstein, J. C . , 137.Eisfeld, K., 239.Eisner, M., 12.Elad, D., 222.Elder, C. C., 336.Elderfield, R. C., 247.El Din, A. M. S., 23.Eldred, V. W., 137.Eley, D. D., 59.Elhaiez, F. A. A., 160.Eliasson, N.A., 330.Eliel, E. L., 164, 169, 170,Ellinger, F. H., 138.Elliott, A., 292.172, 196394 INDEX OF AUTHORS’ NAMES.Elliott, D. F., 12, 283, 288.Elliott, M. C., 375.Elliott, N., 137.Elliott, P., 213.Elliott, W. H., 270.Ellis, B., 272.Ellis, P., 122.Ellis, S., 54.Elming, N., 241.Elmlinger, A., 134.Elson, L. A., 321.Elvers, H., 371.Elvidge, D. A., 366.E l Wakkad, S. E. S., 23.Elwell, W. T., 356.Elwyn, D., 333.Emanuel’, N. M., 41, 47,Emelhus, H. J., 115, 132.Emerson, E. S., 56.Emery, E., 74.Emke, H., 260.Emlreev, E., 18.Emmelot, P., 348.Emmons, W. D., 190, 240.Endow, N., 33.Engel, J., 37.Engelhardt, E. L., 332.Engelhardt, R. E., 235.Engelhardt, V. A., 209.Engell, H. J., 25.England, L.J., 370.Englard, S., 308, 313.Engle, R. R., 263.Englert, M., 282.English, J . P., 282.English, R. J., 203, 213,Engstrom, L., 318.Enikolopyan, N. S., 30.Enkoji, T., 250.Ennor, K. S., 294.Enns, T., 317.Enslin, P. R., 227, 228.Entschel, R., 202.Epple, li., 101.Ercoli, R., 124.Erdey, L., 359, 362, 369,Erdtman, H., 216, 219,Erickson, J. G., 239.Erlandsson, G., 7.Erlikl, I. %I., 89.Ernst, A., 358.Errede, L. A., 228.Ershler, R. V., 28.Erwin, M. J., 286, 318.Eschenmoser, A., 170, 182,Eschnauer, H., 362.Esin, 0. A., 28.Esmay, D. L., 191.Essen, L. N., 143.Esser, G., 242.Esser, H., 285.48, 49.348, 360.378.220.223, 237.Estrada, H., 225.Ettala, T., 276.Ettlinger, M. G., 208, 209,Ettlinger, R., 249.Eugster, C.H., 201, 202,Evans, A. G., 58, 148.Evans, D. E., 185,263,268.Evans, D. F., 134.Evans, F. W., 73.Evans, W. H., 252.Eveleens, W., 256.Everest, D. A., 107, lG8.Everitt, P. M., 148.Evers, E. C., 95, 108.Evstigneeva, R. I?., 257.Ewald, A. H., 52.Exley, D., 305.Eyler, E. H., 325.Eyring, G., 181.Eyring, H., 149.Eyring, L., 130, 131.Fagerlund, U. H. M., 269.Faillard, H., 321, 325.Fainberg, A. I<., 159.Fairbrother, D. M., 73.Fairweather, A., 84.Falcone, A. B., 313, 314.Falcotet, R., 199.Falius, H., 111.Fandiiio, G., 207.Fano, L., 100.Fanshier, D., 312.Farag, A,, 370, 371.Farkas, A., 318.Farkas, L., 318.Farlow, N. H., 366.Farmer, J . B., 33.Farmer, R. H., 252.Farnov, H., 217.Farnum, F.B., 200.Farrar, T. C., 14, 312.Farrar, M. W., 275.Farrell, M. A., 342.Farrington, J. A., 288.Fassender, H., 355.Faua, F., 269.Fauss, R., 377.Fava, A., 11.Fayiga, T. O., 157.Fazakerley, H., 225.Fedneva, Ye. at., 98.Fedora, L. S., 60.Feely, W., 248.Fegley, M. F., 200, 240.Feh@r, F., 117.Feigl, F., 355, 356.Feldstein, A., 270.Feliu, S., 25.Feltham, R. D., 10, 128.Felton, D. G. I., 239, 249.Fennell, T. R. F. W., 358.Ferguson, E. E., 148.Ferm, R. J., 105.212.209, 261.Ferradini, C., 65.Ferraro, C. F., 89, ‘30.Ferry, J . D., 89.Fertig, J., 111.Fessenden, R. W., 14.Fett, H., 256.Feurer, M., 288.Fevold, H. L., 346.Fialkov, Yu. Ya., 44.Fianu, P., 189.Ficken, G. E., 361.Fidler, W. E., 249.Fields, P.R., 138.Fierens, P. J . C., 157, 159,Fieser, L. F., 266, 267.Figgis, B. M., 95.F’ilbey, A. H., 194, 232.Finke, H. L., 83.Finkelstein, M., 237.Finkle, B. J., 278.Finn, B. M., 282.Firestone, R. F., 66.Firth, M. E., 319.Fischer, A. K., 74.Fischer, B., 247.Fischer, E., 85, 87.Fischer, E. O., 128, 129,Kscher, H., 17, 29.Fischer, J., 33, 120, 133.Fischer, V., 376.Fisher, D. W., 373.Fisher, E. S., 26.Fisher, H. F., 308, 312.Fitches, H. J. M., 64.Fitting, C., 312.Fitzgerald, E. R., 89.Fitzky, H. G., 7.Fitzpatrick, J. D., 207.Fitzpatriclr, T. J., 278.Flahaut, J., 130, 136.Flaks, J. G., 335, 337, 338.Flaschka, H., 359, 365.Fleck, R. B., 214.Fleischmann, M., 22, 24.Fletcher, J. M., 130.Fletcher, N. W., 372.Flitcroft, T., 76, 78, 149.Flitman, R., 47.Florey, H.W., 341.Florey, M. E., 341.Flory, P. J., 58.Floss, J. G., 126.Flotow, H. E., 382.Flowers, R., 150.Fluck, E., 141.Flynn, E. H., 210.Flynn, J. H., 30.Fodor, G., 171, 254.Folkers, K., 203, 204, 242,Foltz, C. M., 175.Fonken, G. J., 272, 276.Forbes, W. F., 185.Forbes, W. G., 38.161.239.274, 349INDEX OF AUTHORS’ NAMES. 395Ford, 11. W., 33.Ford, J. H., 340.Ford, M. C., 242.Foreman, J. K., 137, 373.Forrester, J . S., 140.Forsling, W., 50, 238.Foss, M. E., 140.Foster, A. B., 293, 300,Foster, D. J., 193.Foster, M. R., 12.Fournier, A., 182.Fournier, A., jun., 160.Fowden, L., 278.Fowler, J. F., 57, 69.Fowler, L. R., 262.Fowles, G. W. A., 95,Fowlks, W, L., 309, 310.Fox, c.L., 336.Fraenkel, G. K., 11, 115.Fraenkel-Conrat, H., 280.Francis, T., 326.Franck, B., 250.Prank, I. F., 314.Franklin, C. S., 188.Franzl, R. E., 208.Fraser, R. li., 232.Freegarde, M., 354.Freeman, J. H., 118.Freeman, R., 12, 1.5.Freidlina, R. K., 131.Frennet, A., 157.Freon, P., 196.Freter, K., 243.Frey, A. J . , 170, 223, 224,Frey, F. W., 124.Frey, 13. M., 40.Frey, S. W., 167.Freymann, M., 88.Freyschlag, H., 252.Frick, H., 242.Fried, S., 138.Friedberg, F., 295.Friedel, R. A., 189.Frieden, C., 309, 312.Frieden, E., 47.Friedlander, H. N., 62.Friedlina, R. Kh., 167.Friedman, A. M., 138.Friedman, H., 338.Friedman, H. L., 39.Friedrich, R. E., 59.Fristrom, R. M., 8.Fritz, C.G., 236.Fritz, G., 106, 107.Fritz, H. P., 128, 239.Fritz, J. S., 362, 364.Froemsdorf, D. F., 164.Frohardt, R. P., 336.Fromageot, C., 281.Fromin, H. J., 315.Frost, D. C., 81.Frostick, F. C., 190.Frow, F. R., 83.304.133.258.Frunikin, A. N., 18, 26,Fruton, J. S., 310.Fry, E. &I., 245.Fuchs, R., 167.Fudge, A. J., 134.Fiirst, A., 186, 242.Fujimoto, G. I., 211.Fujino, Y., 208.Fujioka, G. S., 106.Fujita, J., 123.Fujiwara, S., 69.Fukushima, D. K., 175,Fuller, A. T., 243, 346.Funaltoshi, K., 220.Funt, B. L., 89.Fuoss, R. M., 86.Furter, H., 264.Furukawa, J., 60.Fusari, S. A., 336.Fuschillo, N., 12, 16, 70.28, 29.263.Gabor, V., 287.Gadecki, F. A., 236.Gadient, F., 208.Gaumann, E., 249.Gaumann, T., 182.Gagneux, A., 215.Gai (Gaj), B.J., 193, 233.Galbraith, A. R., 199, 234.Galiba, H., 47.Galinowski, F., 255.Gallagher, G. A., 50.Gallagher, T. I?., 263.Gallicchio, V., 348.Gamble, N. W., 246.Gamsjager, H., 382.Gander, J. E., 300.Ganellin, C. R., 237.Ganguly, B. K., 224.Gansser, C., 203, 2C4.Garbisch, E. W., jun., 158.Garcia-Sharp, F. J., 230.Gardner, D. M., 11, 115.Gardner, J. A. F., 237.Gardner, J . E., 244.Garif’yanov, N. S., 11.Garisch, E., 255.Garner, C. S., 44, 122.Garner, R. H., 75, 214.Garnett, J. L., 380.Garrison, A. K., 7.Garrison, L., 341.Garrison, W. M., 63, 68.Garton, G., 103.Garvin, D., 34.Garwood, R. F., 169.Gasperin, M., 133.Gasser, R. J., 305.Gatehouse, B. M., 123.Gates, M., 236.Gatoo, H.C., 25.Gatti, R., 119.Gaudiano, G., 242.Gauhe, A., 305.Gault, F. G., 213.Gautschi, F., 224.Gavat, M., 62.Gaylor, V. F., 365.Gaylord, N. G., 53.Gaze, R., 131.Gazith, M., 168.Gazo, J., 123.GebauerovA, A., 300.Gebert, W. H., 270.Gedin, H. I., 279.Geeren, H., 210, 285.Gehrig, L. B., 339.Geiger, R., 291.Geilmann, W., 302.Geissman, T. A., 219, 252.Gel’man, A. D., 143.Gempeler, H., 253.Gensler, 14’. J., 196, 2G.3,Gentil, V., 356.Gentles, M. J., 267.George, P., 10.Gerding, N., 113.Gerhart, H. L., 192.Gerischer, H., 22.Germain, J . E., 38, 213.Gerowith, M. -4., 18.Gerrard, W., 101, 102, 111,Gershkovich, I. A., 18.Gersmann, H. R., 189,Gerzon, K., 810.Geschwind, I. I., 283.Gesser, H., 40.Getzendaner, M.E., 336.Geulen, H., 111.Gey, K. F., 203, 275.Geyer, A. ill., 55, 167.Ghatak, V., 224.Ghe, A. RI., 366.Ghormley, J., 12.Ghosh, P., 295.Ghosh, S., 49.Giacomella, G., 70.Giacometti, G., 45.Giallombardo, H. J., 175.Giannini, U., 62, 102.Gianchetti, E., 61.Gianturco, M., 212.Giauque, W. F., 116.GiFb, T. R. P., jun., 135.Gibbons, A. J., 108, 192,Gibbons, M., 325.Gibbons, R. A., 325.Gibbs, H. H., 180.Gibbs, M. H., 275.Gibson, E. J., 68.Gibson, J. F., 10.Giddings, J. G., 30.Gidel, A,, 89.Gierst, L., 29.Giesbrecht, A. M., 306.Giese, W., 111.206.232, 240.232.194396 INDEX OF AUTHORS NAMES.Giguere, P. A., 33.Gile, H. S., 363.Gilfillan, J. L., 204.Gill, J. S., 136.Gill, N. S., 124.Gilles, P.W., 78.Gillespie, J. F., 200.Gillespie, R. J., 93, 108,116, 150, 151.Gilman, H., 136, 167, 191,193, 233, 239.Gilmore, M. L., 272.Gilmour, A., 90.Gilon, M., 157.Ginsburg, V., 312.Gintis, D., 78, 163.Ginzburg, S. I., 139.Girard, P., 89.Gish, D. T., 291.Gladyshev, B. N., 305.Glasner, A., 135.Glazer, J.. 52.Gleason, E. H., 51.Gleisner, R., 220.Glemser, O., 116, 370,Glick, H. S., 31.Glick, M. C., 320.Glick, R. E., 15.Glines, R., 69.Glogger, I., 153, 181.Gmelin, R., 209.Godzesky, C., 342.Goebel, W. F., 319.Goehring, M., 141.Goering, H. L., 159, 160,Gortz, H., 97.Goffinet, B., 272, 287, 289.Goishi, W., 42.Gold, A. M., 276.Gold, V., 151, 152.Goldberg, A. E., 39.Goldberg, M. W., 249.Gol’denshtein, I.S., 18.Goldenson, J., 13.Gol’dfarb, Yu. Ya., 61.Goldfinger, P., 38, 82.Goldhagen, S., 83.Goldkamp, A. H., 272.Goldman, A., 45.Goldman, I. M., 217.Goldschmidt, S., 181.Goldsmith, B. J., 91.Goldsmith, H. L., 170.Goldstein, B., 160.Goldstein, D., 356.Goldstein, J. M., 10.Goldstein, L., 56.Goldthwait, D. A., 334,Gollnick, K., 267.Golub, M. A., 54.Gdmez, C. G., 348.Gompper, R., 242, 245.Good, R. J., 86.372, 374.163, 168, 177, 178.335.Good, W. D., 73, 76, 83.Goode, J. M., 118.Goodman, C. H. L., 97.Goodman, J. J., 351.Goodman, M., 287.Goodwin, S., 256.Goodwin, T. W., 203.Gopalan, M. R., 55.Gordon, A. S., 37, 38, 40.Gordon, E., 35.Gordon, J. T., 332.Gordon, M., 336, 341, 348.Gordy, W., 7, 8, 11.Gore, I.Y., 276.Gore, P. H., 151.Gorsich, R. D., 233.Gortatowski, M. J., 180.Gorton, B. S., 249.Goswami, A., 26.Goton, R., 81.Gots, J. S., 337.Gottlieb, D., 348.Gottlieb, 0. R., 266.Gottschalk, A., 208, 319,320, 321, 322, 323, 324,325, 327, 328, 329.Goubeau, J., 100, 101, 111.Gougerot, L., 25.Gould, D., 272.Gould, E. S., 239.Gould, R., 203.Gould, R. G., 275.Goutarel, R., 257, 258,Govindachari, T. R., 254,Gowenlock, B. G., 212.Graber, R. P., 267.Grady, H. J., 331.Granicher, H., 87.Graf, P., 137.Graf, P. E., 33.Graham, P. J., 238.Graham, W. A. G., 98.Grahame, D. C., 17, 28, 29.Graner, G., 248.Grant, E. H., 87.Grant, F. W., jun., 221.Grant, M. S., 229.Grant, P. T., 340, 342,Grashey, R., 169.Grassie, N., 57.Grassmann, W., 287.Graven, W.M., 34Graves, J. L., 308.Gray, A. P., 247.Gray, J. R., 270.Gray, P., 34, 83.Grayson, M., 78, 150, 156,Green, 31. S., 30.Green, R., 54.Greenbaum, AT. A., 179.Greenberg, G. R., 300, 333,259.256, 262343.161.334, 335, 336, 337, 338.Greene, F. D., 178.Greene, F. T., 107.Greenlee, T. W., 186.Greenspan, H., 91.Greenwood, C. T., 57.Greenwood, N. N., 79,Gregory, N. W., 139.Greiner, R. W., 163.Griesbach, L., 245.Griesshammer, H., 128.Grif‘fith, J. S., 10, 15, 93.Grigor’yev, A. I., 96.Grinberg, A. A., 44.Grinstead, R. R., 109.Gripenberg, J., 222, 250.Grisolia, S., 331.Grob, C. A., 208, 215.Grob, E. C., 203.Grobe, Y., 55.Groeneveld, W. L., 102.Groizeleau, L., 195.Gromet, Z., 303.Gross, D., 365.Gross, M.E., 83.Gross, P., 77.Grossman, S., 375.Grossmann, H., 212.Groubert, E., 89.Grovenstein, E., jun., 154,Groves, F. R., 124.Groves, K. O., 42.Growich, J. A., 351.Grundmann, C., 255.Grundy, M. E., 156.Gruen, D. M., 123.Grunanger, P., 216.Grunewald, H. H., 180.Gruenwald, T., 367.Grunberg-Manago, M., 313.Grunwald, E., 16, 51, 159,Grunze, I., 111.Gubler, K., 210.Gunthard, H. H., 12.Guilbot, A., 89.Gundiah, S., 54.Gundlach, G., 286.Gum, S. R., 80, 138.Gunning, H. E., 35, 39.Gunsalus, I. C., 314.Gunstone, F. D., 191, 205.Gupta, A. K., 170.Gurevich, L. T., 24.Gurin, S., 203, 336.Gur’yanova, E. K., 45.Gutmann, H., 202.Gutmann, V., 105, 110,114, 132, 133.Gutowsky, H.S., 12, 13,14, 312.Gutter, F. J., 279.Guttmann, S., 289, 291.Gyarfas, E. C., 124.Gyorgy, I?., 304, 320.103.155.160INDEX OF AUTHORS NAMES. 397Haas, 13. C., 56, 58, 59.Haas, H. J., 305.Haber, C. P., 11 3.Haber, F., 305.Haberland, H., 194, 232.Habermehl, G., 256.Hackerman, N., 2.5.Hadler, H. I., 274.Hadorn, E., 249.Ilaendler, H. M., 94.Hafner, K., 235, 236.Hagedorn, L., 248.Hager, L. P., 314.Haggis, G. H., 87.IIagiwara, S., 17.Hahn, H.-G., 246.Hahn, W., 194, 232.IIain, W. F., 300.Haines, W. J., 340.Hair, M. L., 139.Haissinsky, M., 66.Hajos, A., 287.Hakamori, S., 325.Halbach, K. T., 12.Haleem, M. A., 78.Hales, J. L., 105.Halevi, E. A., 160.Hall, D. M., 148, 181.Hall, G.R., 65, 138.Hall, H. K., 186.Hall, L. C., 363.Hall, L. M., 331.Hall, R. J., 366.Halleux, A., 157.Ilalliday, TV. J., 340.Hallsworth, A. S., 175,189, 265, 266.Halpern, J., 46, 146.Halpern, M., 311.Halpern, O., 210, 253.Halsall, T. G., 214, 221,222, 225.IIam, G., 161.Ham, G. E., 56.I-Zamada, I., 300.Hamann, S. D., 62.Hamer, M., 244.Hamill, W. H., 166.Hamilton, J. G., 367.Hamlen, R. P., 16.Hammarsten, E., 330.Hammer, C. F., 54.Hammerle, W. G., 90.Hammett, L. P., 156.ITammond, G. S., 154,Hanai, T., 87.Hanby, TV. E., 592.Hancock, E. B., 304.Hancock, J. E. H., 309.Hand, J. J., 207, 243.Handler, G. S., 212.Handrick, G. R., 74.Hanger, W. G., 250.Hanke, G.-G., 255.Hanke, M. E., 317.160.Hannaert, H., 161.Hanrahan, R.J., 66.Hansen, R. C., 52.Hansen, S. E., 209.Hanshoff, G., 331.Han Tai, 376.Happ, G. P., 353.Harary, I., 311.Harbottle, G., 43.Hardegger, E., 209, 253,Harden, G. D., 163.Harder, I3., 137.Hardie, D., 107.Hardie, R. L., 166.Harding, J. T., 12.Hardwick, T. J., 48.Hardwick, \V. H., 132.Hardy, D. G., 222.Hare, R., 326.Hargreaves, G. H., 135.Hargreaves, PI. K., 184.Harley-Mason, J ., 248.Harmon, K. M., 236.Harper, B. J. T., 256.Harper, N. J., 187.Harper, 1'. G., 88.Harper, S. H., 210, 212.Harris, C. M., 142, 143.Harris, D. L., 308.Harris, F. E., 88.Harris, G., 214.Harris, G. M., 44.Harris, J . I., 279, 280,Harris, M. M., 180.Harris, S. A., 274.Harrison, I. T., 270.Harrison, J.C., 107.Harrison, R. H., 83.Harrison, W. H., 313.Hart, F. A., 143, 144,Hart, H., 213.Hart, R., 53.Harteck, l]., 6G.Hartley, B. S., 318.Hartley, K., 79.Hartman, I*., 207.Hartman, S. C., 334, 335,Hartmann, A, 292.Hartmann, Il., 108.Hartog, F., 48, 11 6.Harvey, D., 377.Harvey, H., 308.Harvey, J. T., 150, 152,Harvey, W. E., 216.Haskell, T. H., 305, 336.Haslam, J., 360, 363, 367,Hassall, C. H., 191.Hassall, R. C., 226.Hassan, M., 152.Hassel, O., 121.254, 261.282, 283.233.337.154.368, 375.Hassid, W. Z., 301, 312.Hassion, F. X., 86.Hasted, J. B., 87.Haszeldine, R. N., 56, 115,Hatchard, W. R., 214.Hathaway, B. J., 144.Hathway. D. E., 227.Hattier, C., 196.Hauck, F. P., jun., 245.Haun, J. L., 150, 185.Hauser, C.R., 238, 239,Hausmann, W., 285, 346,Haven, A. C., jun., 274.Havinga, E., 272.Havriliak, S., 88.Hawkins, M. C., 90.Hawthorne, M. F., 158,Haworth, R. D., 222.Hayaishi, O., 309.Hayakawa, T., 50.Hayano, M., 309, 310.Haybittle, J. L., 63.Hayek, E., 117.Hayes, F., 302.Hayes, H., 205.Hayman, C., 77.Haymond, H. R., 68.Hayow, E., 65.Hayward, L. D., 304.Hazato, G., 14.Head, A. J., 174.Head, E. L., 74, 131.Heal, H. G., 65, 68.Heaney, H., 194, 233.Hearne, J. A., 78, 136.Heatley, N. G., 197, 341.Hecht, K. T., 9.Hecht, L. I., 330. .Heck, R., 159, 160, 171.Heckert, R. E., 209, 235.Hedberg, K., 110.Hedlund-Stoltz, I., 205.Hegediis, B., 242.Heiba, E. A., 67.Heiba, E. I., 167.Heidelberger, C., 245.Heilbron, (Sir) I., 214.Heilbronner, E., 182, 237.Heilman, W.J., 169.Heimann-Trosien, J., 2 10.Heimer, R., 321.Hein, F., 109, 130, 239.Heine, H. W., 174.Heinke, B., 287.Heinrich, M. R., 329, 330.Heirwegh, K., 281.Heiselt, L. R., 309.Heller, A., 160.Hellin, M., 52.Hellman, M., 228.Helmkamp, G. K., 187.Hemily, P. W., 96.167.244,347.193, 231398 INDEX OF AIJTHORS’ NAMES.Henbest, H. B., 171, 173,175, 178, 189, 191, 262,263, 265, 266, 267.Henderson, J. T., 29G.Henderson, U. V., jun.,Heneka, H., 303.Henery-Logan, K. R., 246,Henglein, A., 68.Henglein, F. A., 303.Henglein, F. M., 179.Hennessy, D. J., 245.Hennig, G. R., 104.Hennion, G. F., 101, 193,Henry, P. M., 51, 123.Henry, R. A., 72.Henry, S. S., 317.Hepler, L.G., 80.Heppel, L. A., 391.Hepworth, M. A., 94, 139,Herbert, E., 330.Herbert, G., 245.Herbert, M., 348.Herbst, H., 111.Herbst, P., 197.Herbstein, F. H., 227.Herdmann, G., 237.HermAnck, S., 248.Hermann, R. A., 169.Hermans, J. J., 90.Herout, V., 218, 219, 220.Herr, E. B., jun., 311.Herran, J., 220.Herring, D. L., 113.Herriott, R. M., 281.Herrmann, E., 240.Herschbach, D. R., 9.Hershberg, E. B., 267,Hershenson, H. M., 376.Herwig, W., 129.Herz, W., 183, 221, 241.Herzenberg, L. A., 278,Herzog, A. H., 111.Herzog, H. L., 267.Hesford, E., 130, 132.Heskins, M., 360.Hester, J . B., jun., 257.Hestrin, S., 303.Hess, G. P., 287, 291.Hess, U., 242.Hess, W., 190, 203.Hesse, G., 186.Heubner, C.F., 258.Heukelom, W., 91.Heumann, T., 26.Heusinger, H., 125.Heusler, K., 267, 275.Heusler, K. E., 25.Heusner, A., 254.Hewett, W. A., 168, 177.Hewgill, F. R., 171, 214.154.287.197.142.272.368.Hextall, P. J., 288.Hey, D. H., 166, 167, 411,Heymes, R., 287, 289, 291.Heyns, K., 190, 319.Heyworth, R., 325.HickinbDttom, W. J . , 169,Hickling, A., 19.Hickmm, J . , 300.Hieber, W., 125, 126.Hiebsch, A., 236.Hietanen, S., 136.Higginson, W. C . E., 46,Higgons, D. J., 381.Higuchi, T., 381. ’Hildebrand, G. P., 360.Hill, N. E., 84.Hill, R. A. W., 76.Hill, R. L., 279.Hill, S., 19.Hille, V., 112.Hillage, A., 48, 116.Hill:, G., 23.Hilton, J., 215.Hilton, M. A., 317.Hilz, H., 307.Himml, R., 132.Hindman, J .C., 42, 43.Hines, R. A., 55.Hinman, R. L., 186.Hinshelwcod, (Sir) C., 38.Hinsvarlc, 0. N., 361.Hintermeier, K., 240.Hirata, T., 35.Hirose, Y., 220.Hirota, K., 67.Hirs, C. H. W., 278, 280.Hirschfelder, J . O., 30.Hirsh, U., 351.Hirshberg, Y., 68.Hirst, G. K., 326.Hirst, J., 157.Hirt, R., 208, 259.Hisada, S., 226.Hisatsune, I. C., 33, 110.Hiskey, C. F., 133.Hitzler, O., 240.Hiyama, N., 322.Hlavka, J . J., 287.Hoagland, M. B., 314.Hoare, D. E., 39.Hobbs, L. M., 54.Hoberman, H., 318.Hobin, T. P., 46.Hoch, M., 82.Hochanadel, C. J., 68.Hochstein, F. A., 351.Hock, H., 189.Hockenhull, D. J. D., 343,348, 349.Hodges, R., 335.Hoeg, D. F., 162.Hoelscher, H. E., 386.Hones, W. J., 139.237.22951, 146.Hoering, T.C., 45.Horingklee, W., 240.Hoette, I., 341.Hoffman, C. H., 2C3, 274.Hoffmzn, J., 240.Hoffman, J. D., 86.Hoffmann, K., 249.Hofmann, A., 258, 260.Hofmann, K., 206, 283,Hofmann, I J . , 105.Hogeb3om, G. H., 315.Hogle, D. H., 89.Hohl, J., 257.Hohlstein, G., 95.Hohn, H., 110.Hokama, T., 100, 234.Hclden, R. B., 96.HoleySovskg, V., 286.Holker, J. S. E., 227.Holker, K. O., 227.Holland, R. S., 84, 85.Holley, C. E., 74.Holley, C. E., jun., 131.Hollingsworth, C. A., 187,Hollnagel, M., 24.Holloway, J. H., 139.Holly, F. W., 203, 242,Holm, C. H., 13, 14, 95.Holm, H. G., 240.Holm, L. W., 138.Holm, K. T., 191.Holman, K. T., 205.Holmes, H. L., 195.Holmes, J . L., 39, 163.Holmes, R. R., 78.Holness, H., 356.Holness, N.J., 164, 172.Holroyd, R. A., 40.Holt, R. J. W., 133.Holum, L. B., 249.Holysz, R. P., 269.Honerjager, R., 7.Honeyman, J., 294, 304.Honig, H., 108.Honig, H. L., 249.Honig, J. M., 384.Honig, R. E., 82.Honzl, J., 289, 291.Hoover, J. R. E., 320.Hough, L., 293.Houlaham, M. B., 330.House, H. O., 195.Housewright, R. D., 348.Horiik, M., 219.Horecker, B. L., 300, 301,Horner, L., 189, 190, 240.Hornig, D. F., 34.Hornig, E. O., 66.Horning, E. C., 228, 256.Hornung, E. W., 116.Horton, W. J., 211.Hoskin, F. C . G., 302.287.212.274, 349.317INDEX OF AUTHORS) NAMES. 309Hoskins, R., 11.Hossenlopp, I. A., 83.Hotz, D., 267.Howald, R. A., 52, 151.Howard, G. A., 213, 214.Howard, K.S., 282.Howard, W. H., 70.Howe, C., 325.Howell, M. G., 184, 187.Howell, W. C., 250.Howlett, K. E., 180.Hsia, S. L., 270.Hsieh, H., 60.Hsu, W. H., 156.Huang, R., 212.Huang, R. L., 167, 168,Huang, W.-Y., 267.Hubbard, W. N., 83.Huber, E. J., 74.Huber, E. J., jun., 131.Huch, A., 62.Huch, C., 62.Hudec, J., 176.Hudis, J., 42, 43.Hudson, D. E., 82.Hudswell, F., 137.Hiickel, W., 248.Huff, J. IV., 204, 275, 330.Huffman, R. E., 47.Huggins, C. M., 15.Hughes, D. E., 310.Hughes, E. D., 150, 158,160, 162, 163.Hughes, H. T., 267.Hugus, 2. Z., jun., 131.Huisgen, R., 153, 169,181, 182, 185, 233.Humber, L. G., 260.Hume, D. M., 376.Hummel, R. W., 383.Humphreys, H. H., 80.Humphries, R. A., 78.Hunt, A. L., 310.Hunt, H., 50, 74.Hunt, J.P., 44.Hunter, G. D., 348, 349.Hunziker, F., 259.Huq, A. K. S., 20.Hurlbert, R. B., 330.Hurley, F. R., 108.Hurst, G. S., 66.Hurwitz, J . , 300, 301, 317.Huskinson, P. L., 249.Hussein, M. K., 26.Huston, J. L., 102.Hutchings, B. L., 241.Hyman, H. H., 120.Idelson, &I., 58.Idler, D. R., 269.Igarashi, K., 215.Ikawa, M., 317.Ikuta, M., 61.Iliceto, +4., 45.Illschner, B., 25.170.Illuminati, G., 153.Imoto, hI., 56.Inagaki, I., 226.Inamine, E., 342, 343.Inghram, M. C., 82.Inghram, M. G., 82, 135.Ingles, T. A., 97.Ingold, C. K., 150, 158,Tngram, D. J. E., 10, 11,Ingram, G., 105.Inhoffen, E., 197, 199.Inhoffen, H. H., 210, 270.Inoue, S., GO.Inoue, T., 26, 138.Inukai, I<., 15.Ioan, V., 229.Ireland, R.E., 28.Irvine, D. H., 4G.Irving, H., 383.Irving, R. J., 123.Isbell, H. S., 295, 382.Iselin, B., 197, 283, 288,Ishihara, T., 226.Ishii, R., 26.Ishimasa, S., 226.Ishishi, E., 125.Isimori, T., 118.Isler, O., 201, 202, 203,Isobe, T., 15.Issa, I. ICI., 26.Isslieb, K., 109.Ito, J . , 77.Ito, K., 15.It6, S., 2GO.Itoh, N., 248.Ivanoff, D., 219.Ivanoff, N., 67.Ivanov, V. I., 297.Ivanovsltii, L. Ye, 132.Ives, D. J. G., 23.Ivin, I<. J., 31, 58, 77, 81.Iwa, I., 220.Izbekova, 0. V., 18.Izgaryshev, 5. A., 19.Izraelevitch, E. .4., 168.160, 163, 179.115.289.275.Jaccard, C., 87.Jaccarino, V., 13.Jache, A. W., 8.Jack, J., 34.Jack, K. H., 94, 107.Jack, W. M., 119.Jacklin, A.G., 199, 206.Jackson, A. H., 240.Jackson, W. M., 82.Jacobs, T. L., 178, 200.Jacobs, W. A., 261.Jacobs, W. M., 21.Jacobson, T. N., 262.Jacobson, &I., 207.Jacques, J., 196.Jager, A,, 240.Jaeger, M., 83.Jaenicke, L., 335, 338.Jaenicke, W., 22.Jaffe, H. H., 110, 161.Jaffe, L., 72.Jagannathan, V., 315.Jahn, A., 267.Jakoby, W. B., 317.James, A. T., 369.Jander, G., 145.Janot, M.-M., 257, 258,Jaquenoud, P.-A., 289,Jarolim, V., 218.Jarrett, A. D., 229, 252.Jarrett, H. S., 10.Jarry, R. L., 119.Jaspert, J., 68.Jayson, G. G., 68.Jeanloz, D. A., 304.Jeanloz, R. W., 304.Jefferies, P. R., 171, 181,Jeffrey, G. A., 206.Jeger, O., 215, 217, 218,225, 226, 227.259.291.184, 214.ellinek, F., 209, 261.encks, TV.P., 313.enkins, A. D., 56.enkins, F. E., 44.enkins, W. T., 317.ennings, R. E., 248.ennings, M. A., 341.ennings, 1’. P., 381.ennings, TV. G., 386.ensen, E. R., 361.ensen, E. V., 262.ensen, R. B., 2G9.epson, TV. B., 79.eskey, H., 196, 231.ohl, A., 289.orgens, F., 365.ohannesen, R. B., 78.ohanessen, D. IV., 336.ohannesson, J . K., 366.ohansen, H . A., 20.ohns, W. I?., 266, 274.ohnson, A. W., 247, 250,347. .Johnson, €3. A., 264.Johnson, E. A., 148.Johnson, I;. B., 17.Johnson, G. 12. A., 65, 67.Johnson, H. E., 182.Johnson, H. W., 209.Johnson, I., 31.Johnson, J. L., 269.Johnson, J . R., 346, 347.Johnson, L. F., 117.Johnson, M. J . , 340, 341.Johnson, R. E., 45.Johnson, W. S., 173, 176,177, 266, 274.Johnston, E.B., 310.Johnston, E. L., 274400 1Johnston, H. L., 82.Johnston, H. S., 30, 33.Johnston, H. W., 165.Johnston, J. D., 276.Johnston, R., 56.Johnston, R. G., 82.Johnstone, R. A. W., 222.Jollks, G. R., 318.Jollbs, P., 281.Jollks-Thaureaux, J., 281.Jolley, J. E., 37, 46.Jolly, W. L., 108.Joly, K., 264.-Jonassen, H. B., 124, 127.Jones, A. C., 17.Jones, D. N., 263.Jones, E., 25.Jones, E. R. H., 163, 192,197, 198, 200, 214, 225,267.Jones, G., 221.Jones, G. D., 59.Jones, H. W., 273.Jones, J. I., 105, 210.Jones, J . T., 359.Jones, L. H., 145, 146.Jones, L. R., 377.Jones, M. E., 307, 331.Jones, M. H., 54.Jones, P., 23, 24.Jones, P. M. S., 148.Jones, R., 13.Jones, R. C., 13, 110.Jones, R.G., 136, 340,Jones, R. N., 262.Jones, W. H., 44, 122.Jones, W. M., 167.Joshi, B. N., 217.Joshi, B. S., 189, 232.Joshi, C. G., 253.Joyner, C. C., 267.Jucker, H., 31, 364.Judel, G. K., 377.Jiirgens, E., 189, 190, 240.Julia, M., 62.Jungers, J. C., 52.Jungk, H., 156.Jurd, L., 252, 253.Jurgeleit, W., 189:Ju-Yu Chen Ho, 196.Juza, R., 95, 133.Kabakchi, A. M., 65.Kabanov, B. N., 26.Kaczka, E. A., 349.Kagi, H., 288.Kaganovitch, R. I., 18.Kahn, J. R., 283.Kainer, H., 165.Kaiser, S., 249.Kajt&r, M., 291, 292.Kalckar, H. M., 316.Kale, M. N., 163.Kalk, F., 165, 189, 232.Kalvoda, J., 222.341.DEX OF AUTHORS’ NAMES.Kalzendorf, I., 242.Kamath, P. M., 58, 59.Kameski, J., 25.Kamiyoshi, K., 91.Kan, K.-Y., 80.Kandrashov, Y.D., 24.Kanecki, J., 23.Kangro, W., 362.Kaniev, N. P., 152.Kanzawa, 184.Kaplan, E. G., 38.Kaplan, L., 295.Kaplan, M., 81.Kaplan, N. O., 308, 309.Kapoor, A. L., 226.Kappeler, H., 283, 289.Kapur, N. S., 377.Kapur, S. L., 54.Kapustinskii, A. F., 80.Kariyone, T., 226.Karlsson, J. L., 333.Karlsson, K. J., 73.Karmas, G., 136.Karplus, M., 14.Karpov, V. L., 70.Karrer, P., 190, 201, 202,203, 225, 245, 249, 257,258.Kasai, P. H., 7.Katagiri, M., 309.Katayoma, K., 228.Kath, J., 270.Kato, K., 17, 345.Kato, S., 49.Katritzky, A. R., 239, 244.Katsoyannis, P. G., 291.Katz, J. J., 120, 379.Katz, L., 140.Kauffmann, T., 256.Kaufman, H. S., 54, 63.Kaufman, S., 310, 314.Kaverzneva, Ye.D., 297.Kawatani, T., 220.Kazakova, Ye. B., 99.Kebrle, J., 249.Keck, J., 251.Keenan, T. K., 43.Keenan, V. J., 67.Keene, J . P., 64.Kehrer, K., 109.Keil, B., 286.Keirs, R. J., 354.Keith, J. E., 74.Keller, F., 258.Keller-Schierlein, W., 249.Kelley, D. J., 60.Kellmann, A., 67.Kellogg, H. H., 131.Kells, M. C., 96.Kelly, R. B., 293.Kelly, W., 230.Kemp, A. D., 274.Kemp, K. C., 310.Kemp, M. D., 83.Kendall, V. G., 206.Kennedy, E. P., 208, 315.Kennedy, F., 208, 212.Kennedy, J. W., 45.Kenner, G. W., 230, 287,Kenner, J., 297.Kenney, H. E., 272.Kent, L. H., 305.Kenyon, J., 197.Keough, A. H., 182.Keppler, H. H., 253.Keppler, S. G., 368.Kern, D. M., 82.Kerr, J. A., 37, 170.Kerr, W. W., 57.Kertesz, 2.I., 71.Kessel, I., 204.Khairy, E. M., 26.Khalafalla, S. E., 23.Khalifa, H., 26, 359, 370,Khan, N. H., 287.Kharasch, M. S., 72, 189,Kheifets, V. L., 19, 27.Khenokh, M. A., 70.Khodadad, P., 136.Khodadadi, G., 90.Khorana, H. G., 300, 301,Kianpour, A., 74, 77.Kidder, G. W., 330.Kieffer, W. F., 157.Kigel’, R. A., 99.Kilb, R. W., 8.Kilby, D. C., 154.Kim, J. S., 115.Kimber, R. W. L., 181.Kimmel, J. R., 281.Kimmel, W., 204.Kincheloe, T. C., 83.King, C. V., 25.King, E. G., 80.King, E. L., 51.King, F. E., 221, 222, 224,King, J. F., 260.King, T. J., 222, 324.King, T. P., 347.Kipping, F. B., 213.Kirchensteiner, H., 242.Kirkbride, F. W., 76.Kirkland, J. J., 386.Kirkwood, J . G., 86, 87,Kirmse, W., 240.Kirsch, W.B., 127.Kirson, B., 124.Kirsten, W. J., 379.Kiseleva, I. G., 26.Kishita, M., 141.Kistiakowsky, G. B., 33,40, 149, 311.Kitahonoki, K., 215, 231.Kivelson, D., 9.Kjaer, A., 209.Klages, F., 115.288.371.191, 232.303, 332.226, 291.90INDEX OF AUTHORS’ NAMES. 401Kleiderer, E. C., 340.Klein, F. S., 160.Klein, J. J., 31.Klein, W. A., 214.Kleinberg, J., 26, 55, 96,Kleinert, P., 130, 239.Klement, R., 112.Klemer, A., 319.Klemm, W., 130.Klemperer, W., 144.Klenk, E., 205, 320, 321,322, 325, 327.Kleppa, 0. J., 81.Kliman, N., 63, 69.Klimentova, N. V., 60.Klohs, M. W., 258.Klosa, J., 197.Kloster-Jensen, E., 182.Kloubek, J., 256.Kluge, F., 230.Klyne, W., 183, 297.Knedler, H., 74.Knee, T. E.C., 150.KnesslovA., V., 286.Knivett, V. A., 331.Knop, C. P., 42.Knorr, C. A., 18.Knoth, I?., 255.Knowles, G., 385.Knowles, W. S., 175, 275.Knox, J. H., 40.Knox, K., 139.Knox, L. H., 75, 149, 237.Knutson, K. E., 378.Kny, H., 215.Knyazhiva, V. M., 26.Kobayashi, M., 123.Kobel, H., 260.Koch, R. C., 241.Kochergin, S. M., 18.Kocheshkov, K. A., 192.Kodama, G., 99.Kogl, F., 209, 261, 348.Kogler, H. P., 129.Koepke, G., 247.Koeppe, 0. J., 312, 313,Koster, R., 188.Koevoet, A. L., 272.Kofron, J. F., 217.Kohn, H. W., 68.Kohnstam, G., 162.Koizumi, N., 87.Kok, H. A., 48, 116.Kolditz, L., 114, 115.Kolesnikov, G. S., 60.Kolitowska, J. H., 112.Kolka, A. J., 194, 232.Koller, E., 217.Kollonitsch, J., 287.Kolotyrkin, Ya.M., 26.KolouSek, J., 70.Koltenburg, G., 212.Komodros, N. M., 25.Kongpricha, S., 119.145.314.Konig, H., 233.Konikova, A. S., 317.Koningsberger, V. V., 314.Kooyman, E. C., 170.Koppelman, R., 317.Korn, E. D., 337.Korey, S. R., 313.Kornberg, A., 312, 330,Korre, D. G., 47.Korst, W. L., 131.Korytnyke, W., 253, 296.Koshland, D. E., 286.Koshland, D. E., jun.,307, 310, 311, 314, 315,316, 318.Koski, W. S., 16.Kosower, E. M., 145.Kost, V. N., 167.Koster, R., 98.Kostka, V., 286.Kotake, M., 261.Kotchetkova, N. S., 238.Kothari, S. C., 54.Koulkes-Pujo, A.-M., 64.KovA.cs, J., 291.Kovacs, o., 171.KovA.?, J., 256.KovAts, E., 182.Kowald, B., 247.Kowalsky, A., 311, 314,Kozikowski, J., 125.Koz’mina, 0.P., 296.Kozyrev, B. M., 11.Kradolfer, F., 249.Kramer, H., 210, 251.Kratsmar-SmogroviC, J . ,Krasikov, B. S., 27.Krasna, A. I., 318, 333.Krasnec, L., 96.Kratoo, I. V., 25.Kraus, J. W., 40.Krawczynski, S., 53.Krebaum, L. J., 217.Krebs, H., 355.Krebs, H. A., 331, 332.Kreevoy, M. M., 75, 149,Krentsel’, B. A., 61.Kresge, A. J., 150, 211.Kress, K. E., 375.Kreye, W. C., 131.Kriek, E., 48, 116.Krien, G., 145.Krimsky, I., 312.Krishna, H. J. V., 217.Krishnaswamy, N. R., 254.Krismer, B., 117.Krohnke, F., 249.Kronenthal, R. L., 215.Krook, S., 77.Kroopf, H., 189.Krotkov, G., 302.Kriiger, G., 305, 329.332.316.96.158.Kruger, S., 244.Kruh, R. F., 142.Kryder, S. J., 119.Krylova, Ye. Ya, 97.Krysiak, R.H., 154.Kuan, T.-T., 80.Kubitz, K. A., 376.Kubo, M., 141.Kubota, T., 216, 227.Kiihnis, H., 245.Kuemmel, D. F., 375.Kuff, E. L., 315.Kuhn, A., 240.Kuhn, R., 241, 305, 319,320, 323, 329.Kuhn, S., 99, 155.Kukina, G. A., 123.Kukshakova, R. D., 136.Kulkarni, A. B., 253.Kulke, H., 97.Kullnig, R. K., 14, 184,Kumas, E., 239.Kupchan, S. M., 173.Kupka, F., 363.Kupstas, E. E., 245.Kurbatov, L. N., 90.Kurland, R. J., 8.Kurokawa, S., 138.Kurosaki, S., 91.Kurras, E., 130, 239.Kursanov, D. N., 45.Kury, J. W., 131.Kusch, P., 96.Kuss, L., 245.Kusserow, G. W., 258.Kusumoto, G., 67.Kusumoto, S., 261.Kutschke, K. O., 37.Kuz’mina, M. F., 35.Kuzminskij, A. S., 70.Kuznetsov, V. I., 52.Kuznetsova, Z. I., 297.Kydd, P.H., 33.Kynaston, W., 105.Laakso, P. V., 246.Labes, M. M., 159.Lacher, J. R., 74, 77.Ladacki, M., 60.Laforgue-Kantzer, D., 26.Lagergren, C. R., 82.Lagerkvist, U., 329, 330,Lagowski, J. M., 247.Laidlaw, R. A., 252.Laidler, K. J., 52, 53.Laird, R. K., 38.Laitinen, H. A., 363.Lakshmikantham, M. W.,Lal, J., 54.Lambert, J. L., 354.Lamouroux, M., 81.Lampe, I=. W., 66, 67.Land, H., 50.293.339.262INDEX OF AUTHORS' NAMES. 402Landel, A. M., 316.Landel, R. F., 89.Landed, J. H., 365.Landers, L. C., 37.Landrum, B. F., 228.Landsberg, E., 302.Landsburg, R., 24.Landskroener, P. A., 53.Lane, E. S., 361, 363.Lang, C. E., 102.Langenbeck, W., 243.Langer, L., 314.Langford, C. H., 362.Lanpher, E. J., 184, 212.LaPidus, J.B., 248.Lapin, H., 272.Lapinskaya, Ye. M., 70.Lappert, M. F., 99, 101,102, 193, 232, 240.Larchar, A. W., 55.Lardon, A., 264, 275.Larsen, D. W., 168, 177,Larson, L. M., 340.La Sala, E. R., 249.Lashua, S. C., 248.Lassner, E., 361.Latham, H. G., jun., 273.Latimer, W. M., 131.Laubach, G. D., 264.Laue, W., 117.Lauenstein, K., 322, 325.Laughlin, J. S., 64.Laughton, P. M., 50.Laurence, G. S., 43.Laurie, C. M., 38.Laurie, V. W., 8.Laurila, U.-R., 281.Lauterbur, P. C., 13, 14.Lavie, D., 227.Lavin, M., 71.Law, H. D., 287.Lawson, A., 242.Lawson, W. B., 214, 244.Lazar, M., 63, 69.Lazarus, A. K., 179.Lea, K., 77.Leaback, D. H., 305.Leandri, G., 148.Leathe, E., 320.Leavitt, F., 169, 178.Le Bot, J., 91.Lederer, E., 222.Lederer, M., 134.Lednicer, D., 238.Ledwith, A., 53.Leeming, P.R., 197.Leete, E., 254.Le F h r e , R. J . W., 85.Leffler, J. E., 147.Lefort, M., 65.Legator, M., 348.leHir, A., 259.Lehmann, G., 233, 535,Lehmann, H., 216.178.246.Lehnerer, W., 247.Leibowitz, Y., 311.Leikis, D. I., 26.Leikis, D. T., 26.Leitz, F. H. B., 254.le Men, J., 259.Lemieux, R. U., 184, 293,Lemin, A. J., 225.Lempfrid, H., 325.Lenlr, W., 230.Lentz, K. E., 283.Le Ny, G., 187.Leonard, H. J., 260.Leonard, N. J., 211, 245.Lerner, A. B., 283.Lerner, B., 208.Lerner, M. W., 373.le Roux, L. J., 45.LeRoy, D. J., 37, 38.Lester, G. R., 170.Lestina, G. J., 243.Leto, J. R., 15.Letort, M., 37.Lettre, H., 267.Letzring, M., 305.Leussing, D.L., 52.Leuthardt, I?., 314.Levenberg, 334, 335, 336,Levey, G., 45.Levi, D. L., 77.Levi, D. W., 90.Levi, H. W., 104.Levin, A. I., 27.Levintow, L., 314, 315.Levitt, B. P., 34.Levy, H. R., 18.5, 212, 308,Levy, L. W., 300.Levy, S., 234.Lewis, B. A., 206.Lewis, C. W., 89.Lewis, I). A., 173.Lewis, J., 95, 114, 189.Lewis, K. G., 211, 241.Lewis, T. R.. 174.Lewis, W. B., 137.Ley, J. B., 150, 160.Ley, K., 165, 189.Li, C. H., 279, 283.Li, K., 83.Liadova, Yu. I., 39.Libbey, A. J., 237.Liberman, A. L., 46.Liberti, A., 369.Libowitz, G. G., 135.Lichstein, H. C., 338.Lide, D. R., 8, 9.Lidzey, R. G., 374.Liebau, F., 107.Lieberman, I., 330, 332.Liebermann, I., 315.Liebster, J., 70.Liedtke, H., 95.Liehr, A.D., 128.296.337.309.Lienhard, K., 303.Likhtman, V. I., 26.Liler, M., 24.Lin, C. C., 8.Lin, H. H., 249.Lin, I., 333.Lincoln, R. M., 67.Lind, S. C., 66.Lindberg, E., 320, 322.Lindberg, M. C., 309.Lindenfelser, L. A., 345.Lindenmann, A., 287.Lindlar, H., 201, 202.Lindley, H., 280.Lindquist, R. H., 95.Lindqvist, I., 145.Lindsay, J. K., 238, 239.Lindsey, A. S., 196, 231.Lindsey, R. V., 185, 238.Lingane, J . J., 362.Linn, B. O., 204.Lions, F., 123, 124.Lipmann, F., 307, 313,Lippmann, A. E., 225.Lipscomb, W. N., 97, 98,Lipsky, S., 67.Little, E. L., 209, 235.Little, J. C., 211.Littlejohn, A. C., 148.Liu, I. D., 33.Liverman, J. E., 276.Livingston, R., 12.Livingstone, A.L., 226.Livingstone, C. E., 142.Livingstone, S. E., 233.Livshits, R. S., 257.Llewellyn, D. R., 45, 160.Llopis, J., 20.Lobanov, A. M., 89.Lock, L. C., 380.Lockhart, I. M., 286, 346,Locksley, H. D., 215.Loeffel, H., 222.Loev, B., 195.Loewenstein, A., 16, 51.Loewenthal, H. J. E., 275.Loewus, F. A., 185, 212,308, 309, 316.Lofthus, A., 149.Logan, W. R., 252.Logie, D., 354, 368.Lohse, F., 209, 261.Lomax, D. A., 38.Lombaert, R., 382.Long, F. A., 51, 147, 186,Long, L. H., 31, 38, 73.Long, V. C., 54.Longi, P., 61.Longone, D. T., 56, 214.Longstaff, J. V. L., 51.Longuet-Higgins, H. C.,314, 331.100.347.297.97, 204, 228INDEX OF AITTHORS’ N.\MES. 403Look, &I., 251.Looney, C. E., 184.Loring, H.S., 300, 330.Lornitzo, F. A., 216.Los, J. M., 297.Los, M., 298.Lossing, F. P., 38, 39,Loudon, J. D., 229, 252.Louis, G., 235.Louwrier, K. P., 48, 116.Love, S. H., 337.Lovell, B. J., 173.Low, E . M., 269.Low, w., 91.Lowenstein, J. &I., 310,Lucas, H. J., 128.Lucena-Conde, F., 369.Luchsinger, W. TV., 313,Luck, C. F., 11.Luck, J. M., 315.Ludemann, W. D., 376.Ludwig, G. W., 16.Luttinghaus, A., 181.Luizzi, A., 64.Lukach, C. A., 170.Lukens, L. N., 333, 337,Luke& R., 204, 256.Lukin, M., 195.Lumb, P. B., 206.Lumieux, R. U., 14.Lund, E. W., 116.Lund, H., 264.Lundberg, R. D., 58.Lundeen, A. J., 209.Lundgren, G., 131.Lutz, E. F., 240.Lyle, R. E., 173.Lynch, B. M., 169.Lynen, F., 204, 307.Lyon, J., 64.Lysenko, Yu.A., 132.Lythgoe, B., 270.Maarsen, J. W., 113.McAdie, H. G., 51.McAtee, J. L., 115.McBee, E . T., 167.McCaldin, D. J., 247.McCaleb, G. S., 270.McCall, D. W., 89.McCarley, R. E., 143.McCarty, J. E., 185.McCarty, S., 130.McClennan, L., 326.Maccoll, A., 39, 163.McConnell, H. M., 9, 10,11, 13, 14, 44, 95.McCormick, C. G., 11.McCormick, H. W., 58.McCormick, J. R. D., 351.McCoubrey, J. C., 33.McCoy, R. E., 78.200.331.314.338.NcCrea, J . F., 327.McCreadie, S. TV. S., 386.McCullough, J. P., 83.McCusker, P. A., 101,MacDonald, S. F., 240.McDowell, C. A., 81.McElvain, S. M., 216.McEwan, I. H. 58.McEwan, W. S., 72.McEwen, W. E., 55, 96.Macfarlane, J. J., 206.McGarvey, B. R., 10.McGeer, E .G., 209, 235.McGeer, P. L., 86.McGhie, J. F., 173.McGill, R. M., 119.McGookin, A., 227, 252.McGrath, W. D., 34.McGregor, A. C., 287.Macgregor, E. R., 46.McGregor, W. R., 95.Mach, E., 249.Machell, G., 298.McHugh, D. J., 172, 293.McIntosh, R., 90, 91.Mackay, D., 242.McKay, F. C., 287.McKay, H. A. C., 130,132, 137, 138.McKee, J. S., 312.McKeever, C. H., 200, 240.McKelvey, J. M., 385.McKenna, J., 263.McKinley, J. J., 77.Mackor, E. L., 151.McKusick, B. C., 209, 235.Maclachlan, J. , 45.Maclay, W. D., 225.MacLean, H., 237.McMichael, R. E., 373.McMurry, T. B. H., 217.McNamara, J. H., 177.McNary, J., 216.McNaughton, G. S., 55,McNerney, W. N., 357.McNesby, J. R., 37, 38, 40.McOmie, J. F. W., 236.McQuillin, F.J., 178.Madayeva, 0. S., 267.Madonia, P., 246.Masiar, P., 286.Magasanik, B., 339.Magat, M., 69, 86.Magee, J. L., 64.Maggio, F., 141.Magnuson, D. W., 8, 119.Magnuson, J. A., 120.Magnusson, E. A., 123.Magoon, E. F., 203.Msh, A. D., 74.Mahan, B. H., 40.Mahieu, A. M., 38.Mahler, W., 113.Mahowald, T. A , , 370.19364, 68.Malwwald, R., 243.Maier, L., 194.Mairinger, F., 114.Maitland, R., 94.Maitlis, P. M., 151, 248.Maizus, 2. K., 47, 48.Majnoni, S., 242.Major, A., 297.Majury, T. G., 31, 58.Makino, M., 228.Makowski, H. S., 101.Makrides, A. C., 25.Malatesta, L., 142.Malchick, S. P., 236.Malhotra, S. C., 132.Malkin, T., 207, 208.Malm, J. G., 142.Malmstadt, H. V., 386.Malter, M. J., 187.Mandel, H.G., 330.Mmdeles, S., 317.Mandelkern, L., 53.Mangini, A., 148.Manjarrez, A., 225.Mann, D. E., 8, 100, 119.Mann, F. G., 144, 233, 247,Mannhardt, H. J., 198.Manning, P. P., 31.Manohar, L., 355.Manson, A. J., 266.hhntica, E., 62.ntmunapichu, K., 254.illitnzoor-i-Khuda, M., 198,Mapper, D., 383.Marbet, R., 202.Marchal, L., 249.Marcus, R. A., 31, 37, 39,Marcus, R. J., 83.Margrave, J. I,., 73, 78,Margreiter, H., 342.Marica, E., 234.Marini-Bettolo, G. B., 252.Marino, G., 153.Marion, L., 254, 255, 358,Mark, H., 60, 63.Markin, T. L., 138.Markin, T. R., 65.Markina, V. Yu., 97.Markov, B. F., 28.Marquet, A., 196.Marray, G. R., 16.Marsh, R. E., 120.Marshall, D., 183, 204, 221.Marshall, J. W., 51.Marshall, R.O., 331.Marshall, S. A., 7.Marshall, W. L., 136.Martel, A. E., 78, 79.Martel, J., 264.Martens, G., 38.Martin, D. G., 274.251.205.41.80, 119.261, 262404 INDEX OF AUTHORS’ NAMES.Martin, E., 342.Martin, G., 195.Martin, G. A., 136.Martin, G. A., jun., 136.Martin, J. C., 160, 209.Martin, K. V., 123.Martin, R., 139.Martin, R. H., 161.Martin, R. J. L., 160.Martin, R. L., 144, 145.Martin-Smith, M., 255.Martinsson, A., 325.Marvel, C. S., 165, 242.Maryott, A. A., 119.Marx, W., 252.Masamune, H., 325.Masamune, O., 326.Mashio, F., 49.Mason, G. W., 138.Mason, H. S., 309, 310.Mason, S. F., 248.Mason, S. G., 91.Masri, E., 65.Massengale, J. T., 195.Massicot, J., 254.Massie, W. H. S., 363.Massy-Westropp, R.A,,203, 230, 254, 348, 350.Mateos, J. L., 187, 264.Mathews, D. M., 142.Mathias, A. P., 300, 303.Mathieson, A. R., 59.Mathieson, D. W., 207.Mathieu, J., 264.Mathieu, J. P., 262.Matreyek, W., 57.Matschiner, J. T., 270.Matsuura, T., 216, 241.Matteson, D. S., 241.Matthies, H. G., 251.Mattok, G. L., 296.Matyukhina, L. G., 225.Mauch, H., 108.Maudgal, R. K., 260.Maurer, J. J., 89, 90.Maxwell, C. R., 48.Maxwell, E. S., 316.May, E. L., 245.May, P. J., 174.Mayaudon, J., 300.Mayer, H., 245.Mayer, J. R., 75, 149.Mayer, R., 243.Mayo, D. W., 238.Mayo, F. R., 170.Mays, J. M., 13, 16.hEtzor, L., 378.Mazzanti, G., 61, 62, 63,Mead, E. J., 98, 188.Mead, T. H., 340.Meade, E. M., 198.Meador, W.R., 75, 149.Meakins, G. D., 262.Meakins, R. J., 84. 86, 87,10288.Mechoulam, R., 263.Medard, L., 72.Meek, G. A., 311.Meen, R. H., 167.Meggle, R., 18.Meguri, H., 228.Mehl, W., 28.Mehrotra, R. C., 131.Meiboom, S., 16, 51.Meier, J., 199.Meigh, D. F., 160.Meinwald, Y. C., 230, 235.Meisenheimer, J., 158.Meisenhelder, J. H., 282.Meissner, E., 240.Meister, A., 314, 315.Meister, H., 104.Melander, L., 154.Melera, A., 215, 226, 227.Mellon, M. G., 375.Melnick, I., 336, 336.Melnick, M. A., 43.Meloche, V. W., 139, 145.Meloun, B., 286.Meltsner, B. R., 249.Melville, H. W., 54.MenEik, Z., 58.Mergenthaler, E., 153.Merrett, F. M., 56.Merrick, J. M., 302.Merrifield, R. B., 285.Merritt, W. D., jun., 157.Merz, K. W., 216.Merz, W..385.Meschi, D. J., 115.Meshitsuka, G., 67.Mesrobian, R. B., 47, 55,Messerly, J. F., 83.Mester, L., 296, 297.Metz, D. J., 69.Metzler, D. E., 317.Meuwsen, A., 146.Meyer, E. G., 43.Meyer, K., 321.Michel, W., 22, 77.Michelson, A. M., 332.Michl, H., 278.Mickel, J. P., 42.Middleton, S., 246.Middleton, W. J., 209,Mihail, R., 61.MikeS, 0.. 286.Mikhailov, G. P., 89.Mikheyeva, V. I., 97, 9s.Milas, N. A., 271.Miliotis, J., 102Milkovitch, R., 60.Millar, I. T., 194, 233.Millar, R. C., 88.Millen, D. J., 110.Miller, A., 40.Miller, B., 169, 170.Miller, C. S., 330, 332,69.235.336.Miller, J. G., 50.Miller, J. I., 376.Miller, J. W., 364.Miller, N., 64.Miller, P., 342.Miller, P. A., 361.Miller, R.C., 96.Miller, R. W., 338.Miller, W. G., 30, 312.Millin, D. J., 205.Mills, J. A., 296.Mills, J. S., 225.Mills, 0. S., 125.Milner, D. C., 57, 69.Milner, G. W. C., 359.Milstead, J., 138.Milsted, J., 138.Milyutinskaya, R. I., 168.Mine, T., 18.Minematsu, M., 17.Minhaj, F., 148.Minkoff, G. J., 38, 41.Mino, G., 51.Minoura, Y., 56.Misch, R. A., 26.Mishima, H., 256.Miskel, J . J., jun., 241.Mislow, K., 179.Misra, G. S., 56.Mitchell, H. K., 278, 330,Mitchell, J. C., 58.Mitchell, P. W., 12.Mitra, C., 227.Miura, M., 49.Miyaia, T., 49.Mizushima, S., 123.Mizutani, Y., 56.Moat, A. G., 338.Mode, R. A., 171.Model, A., 332.Moe, H. J., 66.Rliidritzer, K., 109, 229Mollenkamp, H., 243.Mortsell, M., 116.Moffat, A., 50.Moffatt, J.G., 301, 303.Moffitt, TV., 93.Mohai, B., 82.Mok, S. F., 158.Mole, T., 153.Moline, S. ?V., 138.Molnar, D. M., 348.Monahan, R., 210.Monchik, L., 64.Monnier, G., 145.Monoszon, A. M., 30.Monsimer, H. G., 226.Montag, W., 205.Montagner, S., 91.Montavon, M., 201, 202.Montgomery, J. A., 249.Montgomery, P., 74.Moody, D. P., 222.Moon, S., 238.Mooney, E. F., 367. .332, 368IMoore, B., 95, 189.Moore, F. L., 366.Moore, J. E., 343.Moore, R. E., 186.Moore, S., 278, 280.Mooren, D., 245.Moraglio, G., 63.Morales, M. F., 78.Morehouse, M. G., 313.Morgan, B. H., 71.Morgan, E. D., 205.Morgan, J. W. W., 226.Morgan, K. J., 359.Morgan, W., 255.Morgan, W. T. J., 321,325, 326.Mori, Y., 56.Morita, H., 162.Morlock, G., 29, 245.Morozova, M.P., 80.Morrell, A. G., 38.Morris, A. G., 119.Morris, C . J., 276.Morris, L. J., 191.Morrison, G. H., 383.Mors, W. B., 256.Morse, B. K., 49.Mortimer, D. C., 341.Mortimer, G. A., 215.Morton, J. W., 193.Morton, R. A., 203.Moseley, F., 31.Moser, H. C., 46, 146.Moser, P. W., 8.lllosher, W. A., 296.Moss, J. H., 115.Moss, L. K., 300.Mosthaf, H., 219.Mott, N. F., 21.Motz, K. L., 238.Moubasher, R., 253.Moulton, R. W., 18.Moye, A. J., 364.Moye, C. J., 249.Moyer, A. W., 282.Moyer, J. D., 382.Moynehan, T. M., 237.Miihlbauer, E., 115.Muhlstadt, H., 237.Muller, A., 244.Muller, E., 165, 189.Mueller, W. A., 183.Muller, W. J., 21.Muetterties, E.L., 16, 100,114, 118.Muhammad, S. S., 78.Muir, H., 304.Jluir, J., 91.Muir, R. D., 272.Mukharji, P. C., 275.Mukherjee, T. K., 305.Mulay, L. N., 12.Aiuldrow, C. N., 80.Muller, H., 239.hluller, N., 13.hlotl, o., 220.DEX OF AUTHORS’ NAMES. 405Mullilten, R. S., 148, 149,Munch-Petersen, A., 3 12.Munday, D. A., 156.Murakawa, T., 25.Murao, S., 345.Murmann, R. K., 46.Murray, RI. A., 230.Murray, M. F., 264.Murrill, N. M., 270.Musso, H., 251, 256.Muus, L. T., 54, 91.Muxfeldt, H., 210, 230.illyagkov, V. A., 58.Myasoedova, G. V., 52.Mycek, M. J., 310.Myers, E., 82.Myers, J., 331.Myers, R. J., 7, 115.lLlykolajewycz, Ii., 367.Naclimansohn, D., 3 10.Nadkarni. M. N.. 357.152., -~Nagarajan, K., 254, 256,262.Nager, U., 285.Nagiev, 31.F., 41.Nair, P. M., 13, 184.Najjar, V. A., 316, 318.Nakamoto, K., 123.Nakamura, I-I., i28.Naltazaki, At., 11, 165.Nakhre, P., 303.NaDier. D. R.. 235.Nabolitano, J. l’., 194,232.Sarasinilian, N. S., 227.Karayanan, K. M., 377.Xarayanan, V. V., 206.hTarychkina, T. I., 213.Nasipuri, D., 222.Nast, R., 128.Nataksuka, T., 220.Nath, B., 206.Nathansohm, G., 270.Natta, G., 60, 61, 62, 63,Kaughton, M. A., 282.Xaused, K., 117.Nazarov, I. N., 224.SCclivatal, A , , 170, 323.Keeb, R., 362.Negita, H., 16.Keipp, L., 249.Nelson, G., 77.Nelson, K. L., 78.Nelson, K. le R., 155.Nelson, N. A., 213.Nelson, S. M., 90.Neniteseu, C. O., 62.Nenitzescu, C., 229.Nenitzescu, C. D., 234,Nesbitt, J., 90.Kesmeyanov, -4.N., 131,102, 124.235.167, 169, 192, 238.Nethercot, A. H., 9.Neubauer, G., 165, 189,228, 232, 243.Neuberger, A., 309.Neubert, G., 251.Neufeld, E. I?., 312.Neugebauer, C. A., 73, 80,Neumann, H. M., 121, 122.Keumayr, F., 240.Keumuller, A. O., 267.Neunhoeffer, O., 103.Neuperl, H. J., 236.Neuss, N., 258.Nevell, T. P., 295.Nevins, T. E., 176.Nevitt, T. D., 160.Newbold, G. T., 252, 347.Newburg, N. R., 62, 102.Newhall, W. F., 274.Newhaus, 0. W., 306.Newitt, D. M., 38.Newitt, E. J., 41.Newman, B., 150.Newman, P., 179.Newnham, I. E., 132.Newton, G. G. F., 345, 346.Newton, T. W., 47.Ney, E., 380.Niu, C.-I., 280.Nicholas, L., 129, 238.Nicholls, B., 175, 191, 202.Nicholson, A. E., 52.Nicholson, G.R., 72, 78.Nickon, A., 184.Niclause, M., 37.Nicoara, E., 203.Nicolas, L., 54.Niedenbruck, H., 213.Niedenzu, K., 112, 113.Nielsen, A. T., 211.Nigam, H. L., 124.Nigam, S. S., 205, 207.Nijenhuis, B. T., 242, 346.Nikelly, J. G., 385.Nikitina, T. S., 66, 70, 167.Nikulum, V. N., 18.Nilsson, W. A., 206.Nishikawa, T., 9.Nishimoto, Y., 228.Nishimura, S., 186.Nisonoflf, A., 317.Nisselbaum, J. S., 279.Nitzsche, S., 189.Nixon, E. R., 110.Nobis, J. F., 193.Nobel, P. C., 113.Noth, H., 104, 109, 229.Nogina, 0. V., 131.Noltes, J. G., 194.Nonhebel, D. C., 169.Norberg, R. E., 44.Norman, R. H., 89.Norman, R. 0. C., 169.Norman, V., 139.Norman, V. J., 374.119406 INDEX OF AUTHORS’ NAMES.Normant, H., 192, 195.Noro, Y., 226.Norris, T.H., 117.Norrish, R. G. W., 33, 34,North, M. B., 289.Norton, J. S., 204.Norwitz, G., 381.Norymberski, J. K., 263.Nosworthy, J., 70.Noszk6, L., 99.Novoselova, A. V., 96.Nowak, R. M., 242.Noyce, D. S., 160, 175.Noyes, R. M., 45, 166,Noyes, W. A., 38, 40.Nozoe, T., 237.Numerof, P., 341, 348.Nunn, J. R., 206.Nussbaum, A. L., 220, 272.Nyberg, D. D., 208.Nyburg, S. C., 215.Nyholm, R. S., 93, 94, 95,123, 124, 140.Nyquist, H. L., 160, 178.Nystrom, R. F., 187.O’Brien, E., 348.O’Brien, E. L., 55.Ochoa, S., 313.Ockenden, D. W., 246.Odake, T., 91.Odin, L., 320, 321, 322,324, 325.O’Dwyer, J. J., 88.Oel, H. J., 27.Oesper, P., 313.Oestrich, C., 72.Oetting, F., 74.Offenbach.T. A., 55.35, 52.169.Off ergeld, -G., 89:Ofner, P., 308.Ogata, M., 237.Ogata, Y., 156.Ogawa, M., 226.Ogawa, S., 17.Ogawa, T., 49.Ogg, R. A., 33, 78.Ogg, R. A., jun., 13,Ognjanoff, I., 219.Ogston, A. G., 318.O’Hara, F. J., 361.Ohara, T., 261.Ohloff, G., 217, 224.Ohly, K. W., 287.Oita, K., 62.Okabe, H., 40.4, 15.Okamoto, Y., 156, 161,Okano, M., 156.O’Konski, C. T., 88.OlBh, G., 99, 155.OlBh, J., 99, 155.Oliveto, E. P., 267, 272.Ollis, W. D., 239.162.Olsen, D. B., 250.O’Meara, D., 304.Oncley, J. L., 325.Ono, K., 10.Onoprienko, I., 310.Oasterbaan, R. A., 318.Oosterloo, G., 243.Orchik, M., 207.Orekhov, V. D., 65.Orgel, L. E., 15, 93, 94,137, 148, 204.Orochena, S. F., 206.Orstrom M., 332.Orville-Thomas, W.J., 16.Osaac, O., 252.Osborn, E. M., 381.Osgerby, J. M., 238.Osiecki, J., 183, 221.Osswald, G., 241.Oster, G., 55, 56.Oster, G. K., 31, 39, 55.Oster, R., 210.Ostroff, A. G., 98.O’Sullivan, J. F., 249.Otani, S., 49, 347.Ott, A. C., 264, 269.Ottmann, G., 255.Oubridge, J. V., 116.Ouchi, K., 67.Ouellet, C., 33.Ovenall, D. W., 54.Overeem, J. C., 230.Overend, W. G., 294, 300,Overton, K. H., 220.Owen, J., 9, 216.Owston, P. G., 143.Pace, R. J., 108.Page, J. E., 262.Pa@, M., 65.Pai, B. R., 254, 262.Paige, B. E., 375.Pailer, M., 230.Pajaro, G., 53, 63.Pakshver, A. B., 58.Paladini, A., 347.Pallas, E., 242.Palmer, H. B., 34.Pan, S. C., 341.Pande, K. C., 131.Panish, M. B., 119.Panson, A.J., 95.Panson, G. S., 188.Paoletti, P., 141.Papini, G., 83.Pappo, R., 176, 272, 274.Parchen, F. R., 43.Pardee, A. B., 332.Parfitt, S. D., 236.Parisi, G., 207, 243.Park, J. D., 74, 77.Parker, A., 380.Parker, C. A., 386.Parker, S. H., 154.Parks, J. R., 13.304.Parodi, S., 53.Parry, R. W., 99, 114.Parry- Jones, R., 26.Pars, H. G., 146.Parshall, G. W., 238.Parsons, B. N., 38.Parsons, R., 28.Parsons, T. D., 194.Parthasarathy, P. C., 254.Pascual, 0. S., 167.Pasquon, I., 61.Passerini, R., 148, 151.Patai, S., 158.Paterson, W. G., 40.Patrick, A. D., 203.Patrick, T. M., 168.Patzak, R., 360.Paul, H., 215.Paul, M. A., 51, 147.Paulsen, H., 190.Pauncz, R., 230.Pausacker, K. H., 169.Pauson, L.R., 238.Pavan, M., 216.Pavliith, A., 99, 155.Pavlov, B. V., 37.Pavlov, V. L., 44.Payot, P. H., 70.Peabody, R. A., 334, 335.Peacock, R. D., 94, 135,Peacocke, A. R., 294.Yeake, D. M., 356.Peaker, F. W., 54.Pearsall, H. W., 155.Pearson, D. L., 236.Pearson, R. G., 51, 52,Yearson, K. W., 57, 69.Peart, W. S., 283.Pease, D. C., 55.Pease, R. N., 35.Pederson, R. L., 264, 269.Pedler, A. E., 41.Pedley, J. B., 77, 79.Pelchowicz, Z., 219.Pellam, J. R., 12.Pelletier, S. W., 260, 261.Penketh, G. E., 377.Pennington, R. A., 82.Pennington, R. E., 83.Peppard, D. F., 130, 138.Peraldo, M., 62.Percheron, F., 259.Perel’man, F. M., 47.Perera, V., 52.Pereti, E. A., 104.Perkin, W. H., 213.Perkins, P. G., 79, 103.Perold, G.W., 221.Perrin, F., 85.Perrin, P., 192.Perterson, P. E., 182.Peters, E., 46, 228.Petersen, R. C., 28.Petersen, W. E., 300.139.123INDEX OF AUTHORS’ NAMES. 407Prirnas, H., 12.Prins, J. A.; 115.Pritchard, G. O., 37.Pritchard, J. G., 186.Pritchard, T. G., 51.ProchAzka, z., 247.Proctor, G. R., 251.Proctor, K. A., 366.Proffitt, P. M. C., 374.Promel, R., 249.Prosen, E. J., 72.I’roskurnin, M, A., 65.Pruitt, I<. M., 158.Pryce, M. H. L., 137.Pryke, J. M., 229.Pryor, M. J., 25.Przybylska, M., 262.Pshenitsyn, N. K., 139.Pshezhetskii, S. Ya., 23.Pudles, J., 222.Puerckhauser, G. W. R.,Pullman, M. E., 308, 316.Pummer, W. J., 228.Pummerer, R., 211.Putman, E. W., 301, 312.Pyl, T., 246.Quagliano, J. V., 123.Quarck, U.C., 210.Quarterman, L. A., 120.Quelet, R., 167.Quilico, A., 216, 242.Quin, L. D., 140.Quitt, P., 292.167.Peterson, I). C., 48.l’eterson, E., 310.Peterson, E. A., 279.Peterson, M. L., 238.Peticolas, W. L., 54.Petit, A., 262.Petit, G., 83.Petrack, B., 331.Petri, N., 370.Petrie, S. E., 91.Petrova, 2. G., 41.Petrow, V., 272.Petry, R. C., 101, 190.Pettinga, C. W., 210.Pettit, D. G., 208.Pettit, G. R., 230.Pettit, R., 237.Petty, M. A., 351.Peyser, P., 333.Pflaum, R. T., 148.Pfleger, R., 240, 246.Pfleiderer, W., 249.Pflugmacher, A., 106.Pfrengle, O., 365.Phelps, A. S., 351.Philbin, E., 180.Phillips, B., 190.Phillips, G. O., 296.Phillips, P. C., 214.Phillips, W. D., 13,114, 118, 184.Phung, P.V., 67.Picon, &I., 130.Pieper, H., 362.Pierce, J. G., 330.Pierce, L., 8.Piesbergen, U., 128.Pietsch, R., 358.Piette, L. H., 13.Pike, J. E., 274.Pilz, TV., 379.Pimentel, G. C., 15.Pinder, A. R., 255.Pinder, J. A., 37.Pineau, R., 167.Pinguair, A., 157.Pink, R. C., 90.Pinkus, A. G., 115.Pinner, S. €I., 59, 67.Pino, P., 61, 62, 102.Piozzi, F., 216.Piper, T. S., 13, 107, 141Pitt, G. A. J., 203.Pittman, R. W., 23.Pitzer, K. S., 30.Pivoda, A., 96.Pizer, L. I., 316.Pla, L. C., 230.Plane, R. A., 44.Plass, R., 105.1Plattner, P. A., 242, 286.Plaut, G. W. E., 313.Pleass, C. M., 133.Plentl, A. A., 333.Pletscher, A., 203, 275.Pleven, E., 245.Ylieninger, H., 246, 247.Pliva, J., 218, 219, 220.Plooster, M.N., 34.Pocker, Y., 158, 297.Podall, H., 163.Poddar, S. N., 357.Podolsky, R. J., 78.Poisson, J., 259.Poley, J. P., 85, 86.Polgar, N., 205.Politt, J., 199.Pollack, L. R., 382.Pollard, F. H., 41.Pollard, J. K., 276.Pollart, K. A., 240.Polydoropoulos, C., 110.Pomosova, A. V., 24.Pope, S., 304.Popenoe, E. A., 325.PopjAk, G., 203, 275, 278.Pople, J. A,, 14.Popov, A. I., 120, 121,Popper, P., 97.Porath, J., 279.Porter, G. B., 40.Porter, Q. N., 229.Porter, R. S., 119.Porter, W. L., 278.Posener, D. W., 9.Posey, F. A., 46, 51, 122.Pospelova, I. N., 23.Posternalr, T. Z., 316.Potapov, V. M., 179.Potter, E. C., 17, 380.Potter, V. R., 330.Potts, H. A., 241.Pound, R. V., 12.Pourbaix, &I., 21.Powell, A.D. G., 241, 254.Powell, H. M., 103.Powles, J. G., 12, 84, 89.Praeger, M. J., 20.Praill, P. F. G., 59.Prat, L., 369.Prati, G., 55.Pratt, E. F., 247.Pratt, M. W., 83.Preisler, E., 374.Prelog, V., 160, 179, 182,204, 220, 249.Preobrazhensky, N. A,,257.Prescott, G. C., 340.Prescott, J. F., 335.Prestt, B. M., 162.Price, C. C., 168, 196,Price, F. P., 56.Price, S. J. W., 35, 38,Pricer, W. E., 338.Pricer, W. E., jun., 312.Pride, E., 204.Pridham, T. G., 345.Priesing, C., 271.148.200.81.Raacke, I. D., 283.Raal, R., 326.Rabold, H., 109.Rabindran, R., 169.Rabinovitch, B. S., 33, 38.Rabinowicz, J. C., 338.Rabinowitz, J. C., 243.Rabinowitz, J. L., 203.Rabinowitz, M., 346.Rabizzoni, A., 124.Raclrer, E., 300, 312, 317.Racusen, D.W., 318.Rademachers, J., 114.Rado, R., 63, 69.Rafailoff, R., 371, 372.Raffelson, H., 275.Ragland, J. B., 276.Rahtz, D., 243, 256.Rainbow, C., 337.Rainer, C., 187.Rajadurai, S., 256.Rajappa, S., 256.Rakov, A. A., 23.Ralph, A. S., 185.Ralyea, D. I., 178.Ramachandran, K., 343.Ramage, G. R., 248.Ramaiah, N. A., 360.Ramirez, F., 234.Ramloch, H., 247408 INDEX OF AUTHORS, NAMES.Ramsden, 13. E., 108,Ramsey, D. A., 31.Randall, E. W., 244.Randall, J. J., jun., 140.Randles, J. A. B., 17, 26.Rao, D. H., 78.Rao, D. S., 249.Rao, G. G., 381.Rao, V. P. R., 381.Raper, R., 255.Raphael, L., 46.Raphael, R. A., 206.Rapoport, H., 229.Rapp, W., 153.Rapport, M. M., 208.Rastrup-Andersen, J., 8.Rathmann, G.B., 57, 86.Ratner, S., 331.Rau, E., 25.Rauenbusch, E., 153, 204.Rauhut, M. M., 158.Rausch, M., 238, 239.Rausch, M. D., 96.Rausch, R., 245.Ravdel, G. A., 213.Ray, J. D., 33, 78, 80.Reddaway, R. J. B., 361.Reddy, M. P., 67.Redfearn, M. W., 385.Redfield, R. R., 280, 286.Redlich, O., 17.Reece, I. H., 142.Reed, D. H., 234.Reed, J. F., 33, 38.Reed, L. J., 243.Reed, R. I., 262.Reese, R. M., 119.Reeves, L. W., 15.Reeves, R. E., 173, 292.Reeves, R. L., 159.Reggel, L., 189.Rehbinder, P. A., 26.Rehm, C., 381.Rehm, S., 228.Reichard, P., 330, 331.Reichardt, A., 181.Reichert, R., 382.Reichstein, T., 264, 275.Reid, A. F., 311.Reid, C., 15.Reid, D. H., 165.Reilly, C. A., 12.Reilley, C.N., 359, 360.Rein, J. E., 375.Reinhardt, H., 111.Reinheimer, J. D., 157.Reinisch, L., 69, 86, 88.Reinmuth, O., 191.Reitenour, J. S., 54.Reith, W. S., 384.Reitz, D. C., 10.Relyea, D. I., 168.Rembaum, A., 60, 169.Rembold, H., 207.Remers, W. A., 178.192, 194.Rempp, P., 54.Remy, H., 111.Rennhard, H. H., 237.Renton, C. A., 16.Ressler, C., 291.Reusser, P., 249.Reuter, B., 104.Reyerson, L. H., 104.Reynolds, G. F., 364.Rhind-Tutt, A. J., 150.Ribas, I., 207.Ricca, A,, 212.Rice, S. A., 144.Richard, M. J., 364.Richards, C. G., 252.Richards, G. N., 297, 298.Richards, H. C., 164.Richards, R. E., 12, 15.Richards, R. W., 254.Richardson, P. J., 184.Richter, J. W., 274, 349.Richter, R., 270.Rickards, R.W., 350.Rickborn, B. F., 187.Ridd, J. H., 155.Riddick, J. A., 377.Rideal, (Sir) E. K., 31, 90.Ried, W., 200, 230, 252.Rieder, S. V., 316, 317.Riedle, R., 181.Riehl, N., 87.Rieke, C. A., 149.Rieman, W., tert., 368.Riesz, P., 214.Riethof, M. L., 228.Rigby, W., 222.Rigg, T., 68.Riley, C. J., 373.Riley, E. L., 13.Rilling, H., 203.Rimmelin, A., 213.Rinderknecht, H., 276.Rinehart, K. L., 185, 206,Rinehart, K. L., jun., 149.Riniker, B., 183, 262, 283,Riniker, R., 183, 262.Rinno, H., 323.Risk, J. B., 371.Rittenberg, D., 310, 318,Ritter, D. M., 194.Ritter, W., 197, 220, 283,Rivett, D. E. A., 227, 228.Rivlin, I. Ya., 19.Ro, R. S., 164, 172.Robb, J., 304.Robb, J. C., 31.Robbins, R. F., 249.Robbins, P.W., 348.Roberson, C. E., 373.Roberts, C. W., 167.Roberts, E. C., 338.Roberts, G., 262.238, 239, 305.289.333.288, 289.Roberts, G. N., 84.Roberts, H. R., 368.Roberts, J. D., 12, 13, 14,158, 161, 184, 208, 233.Roberts, M. W., 358.Robertson, A., 227, 248,Robertson, A. V., 253.Robertson, D. S., 118.Robertson, J. M., 230.Robertson, P. W., 149,Robertson, R. E., 50.Robertson, W. G. P., 54.Robins, J., 150, 185.Robins, R. K., 249.Robinson, C. H., 172.Robinson, E. A., 108, 116,Robinson, F. N., 274.Robinson, G. C., 159.Robinson, M. J. T., 275.Robinson, P. L., 34, 117,Robinson, R., 256.Robinson, (Sir) R., 205,Robinson, R. A., 17.Rochow, E. G., 15, 106,Rodgers, M. T., 119.Roedig, A., 213.Rosenor, W., 26.Rosinger, S., 64.Rogan, J.B., 160, 215.Rogers, D. J., 26.Rogers, H. J., 330.Rogers, M. T., 192.Rogers, N. A. J., 222.Rogers, N. W., 229.Rogers, R. L., 67.Rogier, E. R., 274.Rohde, W., 165.Roholt, 0. A., 342.Rohwedder, K. H., 100.Rolland, M. T., 91.Rolsten, R. F., 132, 133.Romann, E., 224.Romaniik, M., 215.Romo, J., 268.ROOS, P., 283.Ropp, G. A., 155.Rose, H. E., 354.Rose, I. A., 313, 316, 317,Rose-Innes, A. C., 165.Roseman, S., 302.Rosen, W. E., 273.Rosenfeld, R. S., 263.Rosenberg, A., 325.Rosenberg, H., 238, 239.Rosenberg, R. M., 100.Rosenberg, S. D., 108,Rosenblum, B., 9.Rosenblum, M., 238.252, 253, 254.150, 153, 154.151.139.246, 350.194.318.192, 194INDEX OF AUTHORS’ NAMES. 409Kosenthal, D., 50, 217.Rosenthal, K.I., 18.Ross, J., 325.Ross, S. D., 159.Ross, W. C. J., 221.Rosser, W. A., 34.Rossi, A., 249.Rossman, M. G., 230.Roth, P. I., 57.Roth. R. M., 25.Roth, W., 217.Rothbaum, H. I?., 154.Rothberg, S., 309, 317.Rothman, E. S., 273.Rothstein, E., 156.Rotman, B., 220.Rout, M. K., 259.Roux, D. G., 253.Rowe, G. A., 127.Rowe, J. W., 215.Rowland, R. I,., 204.Rowlinson, J. S., 79.Roy, J . C., 166.Roychaudhuri, D. K., 178,184, 255, 258.Royer, D. J., 145.Rozhkov, I. V., 47.Rudinger, J., 289, 291.Rudolph, P. S., 66.Rudorff, W., 105.Riichardt. C.. 185.Riiegg, R., 201, 202, 203,275.Ruetschi, P., 19, 27.Ruggieri, R., 370.Rumley, M. K., 325.Rundle, R. E., 97, 103,Runeckles, V.C., 302.Kunge, F., 358.Russell, D. W., 207, 288.Russell, G. A., 170.Russell-Hill, D. Q., 157.Rust, F. F., 48.Rutkin, P., 179.Rutkowski, A. J., 101,Rutledge, P., 38.Rutledge, T. F., 192.Ruzicka, L., 215, 226.Ryabinin, A. A., 225.Kydberg, J., 137.Ryder, A., 336.Ryer, A. I., 270.Rygg, R. H., 120, 121,Ryle, A. P., 280.Ryser, G., 202.Saari, W. S., 216.Sacco, A,, 126.Sacconi, L., 141.Sackman, J. F., 73.Saggiomo, A, 200.Saha, N. N., 224.Sahli, K. B., 220.125.193.148.Saika, A., 12, 14.Saini, G., 53.Saito, A., 310.Saito, S., 91.Saito, Y., 325, 347.Sakaguchi, K., 345.Sakal, W., 18.Salama, A., 164.SalamC, L. W. F., 197.Salaria, G. B. S., 355.Salem, T. M., 23.Salemink, C. A., 209, 261.Salmon, J.E., 140.Salmon, L., 383.Salomon, H., 225.Salooja, K. C., 41.Salutsky. M. L., 134.Sambeth, J., 112.Sambura, Z., 25.Sampson, R. J., 161.Samuel, A. H., 64.San Pietro, A., 308, 309.Sanda, V., 247.Sandel, V., 129, 239.Sander, H., 255, 274.Sanderson, A. R., 300.Sanderson, R. T., 98.Sanford, J. K., 161.Sanger, F., 279, 282.Sanne, W., 231.Sannik, C., 272.Santhappa, M., 55.Sargeant, K., 227.Sargent, J., 119.Sargent, R., 368.Sarma, P. L., 381.Sass, S., 376.Sasse, W. H. F., 229.Satchell, D. P. N., 150,151, 152.Sato, G., 91.Sato, M., 26.Sato, Y., 273.Satou, S., 16.Satterfield, C. N., 33.Saucy, G., 201, 2.02.Sauer, H. 119.Sauer, J., 233.Sauer, J. A., 70.Sauer, J. C., 204, 235.Sauer, R., 111.Sauers, C.K., 171.Sauers, R. R., 224.Saunders, A. G., 341.Saunders. D. G., 150.Saunders, R. D., 63.Saunders, W. H., jun., 164.Sauve, D. M., 193.Sauvenier, G. H., 364.Savage, W. R., 82.Saville, B., 376.Sax, K. J., 204.Sax, N. W., 204.Saxer, W.. 24.Sayasov, Yu. S., 30.Sazhin, B. I., 89.Scargill, D., 130, 132.Schaafsma, V., 170.Schabel, F. M., 336.Schade, G., 217.Schafer, H., 131, 139.Schaeffer, H. J., 185.Schaeffer, R., 13, 98.Schaeffer, W. D., 178, 185,Schaffner, K., 225, 227.Scharrer, K.. 377.Scheiner, J., 245.Scheinost, K., 303.Schenck, G. O., 63, 212,Schenk, J., 115.Scherer, P. C., 90.Scherrer, P., 87.Scherrer, R. A,, 218.Schildknecht, H., 230.Schindler, O., 275.Schinz, H., 223.Schisla, R. M., 195, 244.Schlapfer, R., 242.Schlafer, H. L., 77.Schlechte, G., 165, 189.Schlegel, W., 263.Schleppnik, A., 230.Schleyer, P.von R., 215.Schlittler, E., 257, 258.Schlogl, K., 239.Schmid, H., 253, 257, 258.Schmid, K., 325.Schmid, R. W., 182, 350.Schmidlin, J., 264, 275.Schmidt, H. J., 200, 362.Schmidt, M., 104, 116.Schmidt, 0. T., 1SO.Schmidt, P. F., 22.Schmidt, R., 240.Schmidt-ThomC, J., 269.Schmir, G. L., 243.Schmutz, J., 259.Schnabel, W., 68, 69.Schneider, A. K., 214.Schneider, C., 69.Schneider, P. B., 276.Schneider, W., 261, 292,Schneider, W. G., 14, 15,Schnitzer, R. J., 245.Schober, G., 105.Schon, W., 286.Schone, H. H., 321.Schoenheimer, R., 329,Schopf, C., 245, 247, 256.Schofield, K., 152, 246,Schofield, R., 208.Scholes, G., 65, 68, 70, 71.Schomaker, V., 145.Schonland, D., 10.Schott, G.L., 34.Schouten, H., 209, 261.228.267.293.184.333.249410 INDEX OF AUTHORS’ NAMES.Schram, E., 382.Schramm, M., 300, 303.Schreiber, K., 273.Schrodel, R., 186.Schroeder, E., 300.Schroder, G., 245.Schroder, L., 242.Schubert, W. M., 150, 154,Schulde, F., 247.Schulek, E., 368.Schulenberg, J. W., 174.Schuler, N. W., 56, 58.Schuler, R. H., 64, 66.Schulman, M. P., 330,333, 336, 338.Schulte, J. W., 66.Schultz, H., 165.Schultze, G. R., 241.Schulz, G., 274.Schumacher, H. J., 119.Schumacher, R. T., 12.Schuster, L., 125.Schwab, G. M., 53.Schwabe, M., 26.Schwartz, E. T., 283.Schwarz, H. A., 64.Schwarz, J. C. P., 294,Schwarz, R., 111.Schweizer, E.E., 182.Schwenk, E., 276, 350.Schwyzer, R., 197, 283,Scotoni, R., 236.Scott, A. I., 265.Scott, C. B., 189.Scott, D. B. McN., 300.Scott, D. W., 73, 76, 83.Scott, W. E., 249.Scott, W. T., 29.Scovil, H. E. D., 9.Searcy, A. W., 81, 82.Searle, C. E., 242.Searles, S., jun., 240.Seaton, J. C., 258.Sebek, 0. I<., 341.Sedlmeier, J., 126.Sedova, M. F., 41.Seebeck, E., 321, 258.Seed, L., 38.Seel, F., 109, 119.Seelye, R. N., 273.Segal, H. L., 312.Segal, W., 237.Segel, S. L., 16, 17, 103.Segre, A., 207, 243.Sehon, A. H., 71.Seidman, R., 91.Seikel, M. K., 252.Seipt, M., 29.Seiyama, T., 18.Sela, M., 280.Selbin, J., 51.Selton, R., 244.Semeluk, G. P., 39.185.349.288, 289.Semenenko, K.N., 96.Sen, B., 358, 361.Sengupta, P., 220.Senkus, M., 341.Seoane, E., 207.Sephton, H. H., 298.Sergeant, G. A., 374.Sermonti, G., 345.Sernagiotto, E., 217.Serota, S., 273.Serra, M., 25.Seshadri, T. R., 252, 254.Setkina, V. N., 45.Seydel, R., 194, 232.Seyferth, D., 108, 194.Seyhan, M., 191.Shafiq, M., 217, 218.Shafizadeh, F., 297.Shagisultanova, G. A., 44.Shakespeare, N. E., 282.Shamrai, F. I., 97.Shantarovich, P. S., 37.Shapiro, H., 228.Sharon, N., 304, 314.Sharov, V. T., 80.Sharp, D. W. A., 106.Sharp, J. A., 49, 50, 140.Sharp, W., 347.Sharpe, A. G., 118, 140,Sharts, C. M., 14.Shaver, K., 134.Shaw, E. L., 143, 248.Shaw, C. J. G., 294.Shaw, D. F., 294.Shaw, E., 336.Shaw, P.D., 238.Shcherbsk, P. H., 89.Shcherbinin, V. A., 47.Shchukarev, S. A., 80.Sheard, D. R., 81.Shechter, H., 167.Sheehan, J. C., 239, 244,246, 287.Sheft, I., 379.Sheinker, Yu. N., 267.Sheldon, J. C., 110.Shemin, D., 333.Shemyaltin, M. M., 213.Shenstone, F. S., 206.Shepherd, D. M., 304.Shepherd, R. G., 282.Shepp, A., 37.Sheppard, J. C., 43.Sheppard, N., 7, 106.Sherwood, R. M., 375.Shibata, O., 66.Shibata, S., 141, 144.Shidlovskii, A. A., 80.Shieh, N., 161.Shilo, M., 325.Shilov, E. A., 152.Shimizu, &I., 90.Shimizu, S., 216.Shimonaev, G. S., 47.Shimura, Y., 135.141.Shiner, V. J., jun., 150.Shinohara, K., 69.Shiomi, T., 226.Shirley, D. A., 243.Shirshova, A. N., 296.Shive, W., 249, 336, 337,Shoaf, C.J., 188.Shoemaker, D. P., 124.Shoolery, J. N., 12, 13,15, 110.Shoppee, C. W., 164, 185,262, 263, 268.Shotwell, 0. L., 345.Shriner, R. L., 230.Shukla, J. S., 56.Shulman, R. G., 13.Shultz, A. R., 57, 69.Shumway, N. P., 283.Shunk, C. H., 203, 204,Shvetsov, Y. B., 213.Sianesi, D., 53.Sicher, J., 242.Sicre, J. E., 119.Sidbury, J. B., jun., 318.Sieber, P., 197, 283, 288,Siebert, G., 313.Siegel, S . , 120.Siegfried, K. J., 254.Sieglaff, C. L., 131.Siegmann, C. M., 275.Sienko, M. J., 135.Sigal, M. V., 210.Signer, R., 278.Sigoloff, S. C., 64.Si-Hoe, S. S., 170.Silber, P., 217.Silcocks, C. G., 38.Sillars, R. W., 90.Silva, E., 356.Silver, H. B., 232.Silverman, J., 43.Silverman, L., 357.Silverman, M., 338.Silverman, M.B., 194.Silverman, W., 259.Silversmith, E. F., 160,Simanov, Yu. P., 96, 135.Simha, R., 57, 69.Simkin, D. J., 83.Simkin, J., 119.Simmons, H. E., 182.Simmons, €5. E., jun., 160.Simms, E. S., 332.Simms, J. A., 151.Simmons, R. F., 41.Simon, A., 116.Simon, W., 237.Simonsen, (Sir) J., 216,Simpson, D. M., 7.Simpson, L. B., 297.Simpson, T. H., 248.338.349.289.163.217, 221INDEX OF AUTHORS’ NAMES. 41 1Singh, K., 340.Singh, M. P., 296.Sinke, G. C., 71.Sinn, L. G., 280.Siposs, G., 362.Sironen, R. J., 130.Sisler, H. H., 108, 132,Sisti, A. J., 376.Sixma, F. L. J., 161.Sizer, I. W., 317.Sjolander, N. O., 351.Skattebol, L., 192.Skeggs, H. R., 203, 204,Skeggs, L. T., 283.Skell, P.S., 177.Skelly, N. E., 120.Skinner, D. A., 178, 228.Skinner, H. A., 73, 76, 77,Skipper, H. E., 336.Slabaugh, W. H., 363.Slade, P. E., 127.Slater, C. A., 213, 214.Slater, N. B., 35.Slates, H. L., 263, 264.Slaytor, M., 348.Sleep, K. C., 213.Sloan, A. D. B., 229, 252.Sloan, G. J., 10, 165.Slough, W., 148.Sly, W. G., 120.Smales, A. A,, 383.Smart, N. A., 289.Smid, J., 169.Smidt, J., 211.Smidtke, H. H., 77.Smirnov, M. V., 132.Smissman, E. E., 171, 248.Smit, J. van R., 383.Smit, P. J., 151.Smith, A. F., 256.Smith, B., 361.Smith, C. W., 191.Smith, D. B., 228.Smith, D. C. C., 299Smith, D. W., 110.Smith, E. A., 149.Smith, E. L., 278, 279,Smith, G. F., 241.Smith, H., 176, 203, 204,254, 348, 350.Smith, I.C. P., 384.Smith, J. B., 294.Smith, J. C., 206.Smith, J. F., 47.Smith, J. M., jun., 241.Smith, J. W., 17, 37, 84,Smith, L., 73, 77.Smith, L. F., 279.Smith, L. H., 330, 331Smith, L. I., 200.Smith, M., 171, 263.135.330.78, 79, 149.281.148.Smith, N. H. P., 153Smith, P. K., 330.Smith, R. A., 314.Smith, R. F., 37.Smith, R. J. D., 205, 210.Smith, T. D., 137, 373.Smith, W. MacF., 51.Smolinsky, G., 229.Smoot, C. R., 52, 156.Smrt, J., 242.Smyth, C. P., 17, 84, 86,Sneen, R. A., 177, 184,Snelgrove, J. A., 90, 91.Snell, E. E., 317.Snell, J. F., 350.Snoddy, C. S., jun., 267.Snoke, J. E., 315.Snow, C. M., 77.Snyder, H. R., 241.Snyder, R. G., 110.Sober, H. A., 279.Sorensen, N. A., 198.Sogani, N. C., 369.Sogo, P., 10, 128.Sogo, P.B., 11, 165.Sokol, P., 239.Soldatov, M. P., 117.Soliman, A., 359.Solomon, S., 166.Solomons, C., 116, 151.Solt, I. H., jun., 9.Sondheimer, F., 198, 222,252, 263.Sone, K., 144.Sonne, J . C., 333.Sonntag, A., 111.Soper, Q. F., 340, 341.Sorm, F., 215, 218, 219,220, 242, 247, 286.Sova, O., 110.Sowa, J. R., 241.Sowards, D. M., 132.Sowden, R. G., 65.Sowerby, D. B., 114.Sowerby, J., 22.Spackmann, D. H., 280.Spall, B. C., 37.Spector, I,., 331.Spedding, F. H., 82, 131.Speier, J. L., 167.Speirs, J. L., 119.Spence, R. D., 10.Spencer, C. F., 242, 349.Speyer, J. F., 312.Spiegelberg, H., 242.Spilman, E. L., 336.Spinner, E., 150.Spode, E., 55.Sprince, H., 285.Spring, F. S., 347.Springall, H.D., 148, 287.Sprinson, D. B., 310, 333.Sprio, V., 246.Sprunt, D. H., 270.888.187.Spurny, Z., 70.Squire, W., 31.Squirrell, D. C. M., 360,Sribney, M., 208.Srivastava, R. D., 139.Srivastava, S. P., 49.Staab, H. A., 243.Stack, M. V., 340.Stadler, P. A., 170, 223,Stager, H., 89.Staehelin, M., 314.Stafford, F. E., 51.Stahlhoffen, P., 252.Stalmann, L., 274.Stammer, C. H., 242, 349.StanEk, J., 297.Stankovich, T. D., 194.Stannett, V., 47.Starcher, P. S., 190.Staritzky, E., 134.Starostin, S. M., 139.Staub, A., 280.Stauffacher, D., 221, 258.Staveley, L. A. K., 79.Steacie, E. W. R., 31, 37.Stearns, R. I., 124.Stedman, R. J., 291.Steele, E. L., 374.Steele, M. C., 135, 370.Steger, E., 116.Stehle, P., 74.Stehle, P.F., 98.Stein, G., 65.Stein, R., 151.Stein, S. S., 310, 311.Stein, T. W., 33.Stein, W. H., 278, 280.Stein, W. J., 241.Steinberg, D., 317.Steinberg, M., 135.Steinemann, A., 87.Stemmer, H. D., 357.Stender, W., 260.Stenhagen, E., 205.Stening, T. C., 294, 304.Stenlake, J. B., 230.Stephens, R., 228.Stephenson, J. S., 197.Stephenson, N. C., 143.Stephenson, W. H., 381.Stepukovich, A. D., 30,Sterligov, 0. D., 43.Stern, M., 25.Sternbach, L. H., 249.Stetten, D., 330.Stetten, M. R., 336.Steunenberg, R. K., 33,Stevens, C. L., 305.Stevens, C. M., 342, 343.Stevenson, M. J., 9.Steward, F. C., 276.Stewart, D. W., 353.363.224.38.120, 133412 IStewart, J., 336.Stewart, R., 50.Sticherling, W., 270.Stiles, M., 237.Stirling, C.J. M., 166, 211.Stock, L. M., 153.Stockell, A., 278.Stoenescu, F., 61.Stoffel, W., 325.Stokes, R. H., 17.Stokstad, E. L. R., 207,Stoll, A., 221.Stolzenbach, F. E., 300.Stone, D., 310.Stone, F. G. A., 98, 194.Stone, R. W., 342.Stone, W. R., 356.Stork, G., 223, 275.Strandberg, B., 145.Strandberg, M. W. P., 9.Stransk, D. R., 42, 121.Strassman, M., 349.Strauss, U. P., 54.Street, E. H., 108.Strehlov, H., 27.Streibl, M., 218.Streitwieser, A., 185.Strevel, P., 97.Strickland, J. D. H., 371.Stroh, R., 194, 232.Strong, R. L., 33.Struyk, A. P., 341.Stuart, E. R., 217.Stucker, J. F., 235.Stulberg, M. P., 312, 314.Stull, D. R., 71.Stutchbury, H. E., 52.Stute F.B., 120.Subba Rao, B. C., 188.Subramanian, M., 256.Suchy, M., 219.Suddaby, A., 52.Sueyoshi, H., 225.Sugasawa, S., 248.Sugihara, J. M., 304.Suhr, K., 246.Sujishi, S., 100.Sullivan, J. C., 42, 43.Sultanova, A. I., 41.Sumerwell, W. N., 207.Summerbell, R. K., 243.Summers, G. I-I. R., 164,185, 262, 263.Summers, L. A., 229, 252.Sunner, S., 77, 78.Sutaria, G. C., 54.Sutcliffe, L. H., 45, 46.Suter, C. M., 192.Sutherland, E. W., 316.Sutherland, T. H., 89.Susz, R. P., 99, 102.Sutton, L. E., 84, 244.Sutton, W. B., 309.Suzuki, S., 320.Suzuki, T., 300.243.‘DEX OF AUTHORS’ NAMES.Svatos, G. F., 123.Svehla, G., 378.Svendsen, S. R., 116.Svennerholm, L., 321, 325,Swain, C. G., 150, 158.Swalen, J. D., 9.Swallow, A.D., 63.Swallow, A. J., 65, 71.Swallow, D. L., 286.Swan, G. A., 239.Swann, M. H., 376.Swann, S., jun., 224.Swart, E. R., 45.Sweat, M. L., 309.Swedlund, B. E., 150.Sweeney, W. A., 150.Swenson, J., 200.Swenson, R. W., 88.Sweeny, D. M., 123.Sweeting, 0. J., 53.Sworski, T. J., 47, 65.Sy, M., 277.Sjrkora, V., 220.Sylvester, J. C., 340.Symons, M. C. R., 96, 115,Synge, R. L. M., 276.Szabadviiry, F., 369.Szab6, D., 202.Szab6, 2. G., 47.Szab6, 2. L., 368.Szabolcs, J., 202.Szekeres, L., 368.Szelke, M., 288.Szent-Gyorgyi, A. G., 184.Szilagyi, J., 171.Szmuskovicz, J., 217, 274.Szpilfogel, S. A., 275.Szumslti, S. A., 351.Szwarc, M., 60, 71, 72,328.121, 134.168, 169, 178.Taber, W. A., 210, 285.Taft, R.W., 75.Taft, R. W., jun., 15, 149,166, 214.Taher, N., 150.Taimni, I. K., 355.Takahasi, M., 167.Takai, M., 203.Takamoto, S., 138.Takasaki, R., 225.Takase, K., 237.Taltase, S:, 325.Takeda, M., 12, 13.Takeda, K., 215, 231. .Takemoto, T., 228.Talalaeva, T. V., 192.Talalay, P., 308, 309.Talat-Erben, M., 30.Tallent, W. H., 228.Talley, E. A., 278.Tamm, C., 187, 263, 274.Tamura, S., 203.Tanabe, K., 220.Tanaka, S., 123.Tanenbaum, S. W., 317.Tannenbaum, E., 8.Tannenbaum, S. I., 135.Tannenberger, H., 105, 133.Tardif, J., 85.Tarkoy, N., 182.Tarr, D. A., 311.Tarr, H. L. A., 300.Tarrago, X., 65.Tate, D. P., 188.Tateda, A., 118.Tatibouet, F., 196.Tatlow, J. C., 106, 228.Taub, D., 175, 264.Taube, H., 18, 46, 51,Taul, H., 242.Tausend, H., 261.Taussig, P.R., 183.Tavernier, P., 81.Tavormina, P. A., 275.Tayler, J. L., 207.Taylor, C. M. B., 230.Taylor, C. W., 258.Taylor, E. W., 68.Taylor, H. A., 33.Taylor, H. T., 162.Taylor, J. H., 227.Taylor, K. J., 262.Taylor, T. I., 50.Taylor, W., 71.Taylor, W. C., 218, 269.Taylor, W. I., 259.Tchen, T. T., 308, 310,Tedder, J. M., 234.Teitel, S., 249.Temkin, M. I., 28.Temple, C., jun., 249.Templeton, J. S., 185.Tener, G. M., 300, 301,Teodorescu, L., 229.Terenin, A. N., 49.Terentiev, A. P., 179.Tesar, C., 333.Testa, E., 269.Tetaz, J. R., 250.Tetlow, A. J., 247.Thamer, B. J., 134.Thater, F., 165.Thaureaux, J., 281.Thayer, S. A., 270.Theaker, G., 234.Theilacker, W., 165.Theodoropoulas, D., 286.Thesing, J., 244, 245, 247.Thiel, M., 242, 246.Thilo, E., 111.Thirsk, H.R., 22, 23, 24.Thirtle, J. R., 136.Thomas, A. B., 106.Thomas, A. J., 349.Thomas, B. R., 160, 174.Thomas, D. B., 225.122.316.303, 332INDEX OF AUTHORS’ NAMES. 413Thomas, D. K., 79.Thomas, G. H., 266.Thomas, J. H., 58, 148.Thomas, M., 72.Thomas, R. C., 243.Thomas, W. M., 51, 55.Thompson, C. R., 225.Thompson, J. D., 234.Thompson, J. F., 276.Thompson, Q. E., 175,Thompson, S. G., 137.Thompson, T. A., 283.Thompson, W. E., 311.Thomson, R. H., 166, 251.Thorn, J. A., 340.Thorn, R. J., 82.Thorne, C. B., 348.Thornton, D. W., 226.Thornton, F., 220.Thornton, R. E., 176.Thrush, B. A., 33.Thuan, S. T., 211.Thyagarajan, B.S., 176.Ticknor, L. B., 81.Tiedemann, T., 305.Tierney, P. A., 98, 188.Tiers, G. V. D., 151.Tilak, B. D., 249.Timmis, G. M., 249.Tindall, J. B., 341.Ting, I., 154.Tinkham, M., 9.Tipper, C . F. H., 41, 213.Tischer, R. P., 22.Tobolsky, A. V., 55, 59, 60.Todd, (Sir) A., 225, 241,Todd, S. S., 80.Tomorkhy, E., 288.Tomoskozi, I., 171.Tokoroyama, T., 227.Tomarelli, R. M., 304.TomBSek, K., 300.TomA,Sek, V., 286.Tome, J., 342.Toms, B. A., 105.Toms, D., 57.Tomuschat, H. J., 205.Topchiev, A. V., 61.Topliss, J. E., 216.Topliss, J. G., 219, 220,Topper, Y. J., 316, 317.Tordoff‘, M., 55.Torgov, I. V., 224.Torizuka, K., 16.Torrey, H. C., 10.Toth, J., 254.Tourky, A. R., 26.Townes, C . H., 9.Toyama, O., 50.Traber, W., 245.Trau, J., 23.Traynelis, V.J., 241.Traynham, J. G., 167.275.302.222.Trego, K., 357.Treibs, A., 240.Treibs, W., 219, 236, 237.Trementozzi, Q. R., 54.Trenwith, A. B., 34, 39.Trevorrow, L. E., 133.Trifan, D. S., 129, 238.Trippett, S., 208, 253, 270.Tristram, E., 269.Tritch, H., 280.Trojknek, J., 248.Trotman, J., 212.Trotman-Dickenson, A. I?. ,31, 35, 37, 38, 40, 81,170.Trowse, I?. W., 133.Trucco, R. E., 325.Truce, W. E., 151, 188,Trumpler, G., 24.Truter, E. V., 276.Tscharner, C., 201.Tsuchida, R., 128, 135,Tsuda, K., 256.Tsuda, M., 220.Tsuruta, T., 60.Tsutsui, M., 130, 239.Tuck, D. G., 382.Tulkachev, S. S., 24.Tullen, P., 218.Tundo, A,, 148.Tung, L. H., 63.Tunmann, P., 252.Turba, F., 285, 286.Turnbull, J.H., 224.Turner, D. R., 22.Turner, E. E., 148, 181.Turner, J. M., 288.Turner, R. B., 75, 149, 214.Turner, W. B., 197.Turnquest, B. W., 243.Turyan, Ya. I., 18.Tuttle, L. W., 71.Tuttle, T. R., 10, 11.Tuttle, T. R., jun., 10.Tweedie, V. L., 187.Twomey, D., 249.Tyree, S. Y., jun., 139.Ubbelohde, A. R., 33, 148.Ueberwasser, H., 275.Ueno, K., 360.Uffmann, H., 165.Ugi, I., 153, 182.Uhl, W., 115.Uhlenbruck, G., 322, 326.Ukshi, E. A., 27.Ulbrecht, G., 311.Ulbrecht, M., 311.Ulbricht, T. L. V., 236.Underwood, A. L., 375,Unser, M. J., 174.Unterzaucher, J., 378.Uphoff, W., 133.Urban, F., 128.195.143.Urch, D. S., 151.Urech, H. J., 160, 182.Urscheler, H. R., 205.Urushibara, Y., 186.Utne, T., 269.Uyeo, S., 260.Uzman, L.L., 325.Vahatalo, hl.-L., 276.Valenta, Z., 260, 262.Vallarino, L., 126, 127.Valvassori, A,, 63.Vamvacas, C., 257.Van Abeele, F. R., 340,Tian Atta, G. R., 225.van Beek, L. K. H., 90.van Berk, P., 157.Van Den Berghe, J., 63.Van der huwera, D., 38.van der Burg, W. J., 275.van der Heijde, H. B., 364.van der Hoeven, M. G.,van der Kerk, G. J. M., 194,van der Scheer, J., 282.van der Waals, J . H., 151.Vanderwater, J. W., 363.van de Vliervoet, J . L. J.,van Dorp, D. A., 275.Vandrewala, H. P., 246.VanEEek, J., 286.van Houten, S., 113.Vaniscotte, C., 38.Van Langen, J. 0. M.,van Nes, K., 72.van Reijen, L. L., 91.Van Ryssellberge, J., 161.Van Rysselberghe, P., 18,20.van Tamelen, E.E., 216,217, 241, 257, 258.Van Veen, A., 149.van Vunakis, H., 281.van Wazer, J. R., 13, 110.Varde, hl. S., 357.Varner, J. E., 307, 314,Vartanyan, L. S., 48.Vasil’ev, R. F., 49.Vasil’eva, A. B., 30.Vasistha, S. K., 224.Vaslow, F., 310.Vassallo, D. A., 386.Vaughan, G. A., 367.Vaughan, J . R., 289.Vaughan, W. R., 10, 165.Vedeneyev, V. I., 39.Velluz, L., 264, 272, 287,Venanzi, L. M., 127, 142.Vennesland, B., 185, 212,341.242, 346.230.272.157.315.289, 291.308, 309, 316414 INDEX OF AUTHORS’ NAMES.Venstrem, E. K., 26.Venturello, G., 366.Verbanik, C. J., 150.Vercellone, A., 267.Verhoek, F. H., 101, 190.Verkade, P. E., 149, 157,Verloop, A., 272.Verma, J. P., 206.Vermeil, C., 64.Vermilyea, D.A., 21, 22.Vernois, J., 134.Vernon, C. -4., 150, 160,Verzele, M., 214.Veselovskii, V. I., 18.Veselj?, K., 59.Vetter, K. I., 25.Vetter, K. J., 25.Vickars, M. A., 153.Vickery, J. R., 206.Vidale, G. L., 114.Vielberg, F., 106.Vigh, K., 359.Vincze, I., 254.Vining, L. C., 210, 285.Vinogradova, Ye. I., 213.Virgona, A., 341, 348.Virtanen, A. I., 276.Viscontini, M., 249.Vishnu, 360.Visil’eva, V. N., 45.Viswanathan, N., 256.Viterbo, R., 207, 243.Vivo, J. L., 10.VlEek, A. A., 139.Vodopivec, S., 220.Voewdsky, V. V., 39.Vogel, M., 238, 239.Vogel, R. C., 120.Vohra, P., 342, 343.Voigt, A., 46.Voigt, A. F., 146.Vol’f, E., 80.Vollbracht, L., 48, 116.Volman, D. H., 37.Volpi, G.G., 33.von Arnim, E., 70.von Dobeneck, H., 247.von Philipsborn, W., 257.von ’ravel, P., 278.von Ubisch, H., 330.von Wartenberg, H., 76.von Werder, F., 272.von Winbush, S., 103.Voronin, N. N., 18.Vorsina, M. A., 26.Vos, A., 113.Voss, E., 24.207.162, 164.258.Waack, R., 60.Wachters, L. H. J., 115.Waddington, G., 73, 76,Waddington, T. C., 34.83.Wade, K., 79, 103.Wade, R., 291.Wade, W. H., 25.Wadsley, A. D., 133.Wadso, I., 73, 77.Wagland, A. A., 262.Wagner, A. F., 203.Wagner, G., 125.Wagner, P. T., 382.Wagner, R. L., 351.Wagner, W. F., 357.Wahl, A. C., 43.Waisvisz, J. M., 242, 341,Wajon, J. F. M., 244.Wakefield, D. B., 141.Walburn, J. J., 192, 194.Walch, F., 67.Walden, C., 77.Waldman, M. H., 91.Waldmann, H., 225.Waldmann, K., 116.Walens, H.A., 273.Waley, S. G., 285.Walker, B. H., 244.Walker, C. H., 206.Walker, D. A., 213.Walker, E. A., 148.Walker, J., 243, 346.Walker, J. B., 331.Walker, P. G., 305.Walker, T. K., 343.Walkley, J., 46.Wall, L. A., 57, 69, 228.Wall, M. E., 272, 273.Wallace, W. J., 155.Wallach, D. P., 331.Wallach, O., 210.Waller, C. W., 241.Waller, J .-P., 289, 291.Walling, C., 169, 170, 190.Wallraf, M., 371.Walls, F., 220.Walsh, A. D., 39.Walsh, E. K., 54, 63.Walshaw, S. M., 148.Walter, E. D., 225.Walter, R. I., 10.Walters, D. R., 305.Walters, W. D., 35, 40.Walton, E., 203, 274, 349.Walton, H. M., 211.Walz, H., 153, 181.Wang, C. H., 166, 167.Wang, J. H., 311.Wannagat, U., 95, 106, 114.Ward, R., 140.Ward, R.L., 10, 11, 44.Wardlaw, W., 108, 130,Wardle, R., 372.Warf, J. C., 131.Wariyar, N. S., 185, 215,Warnant, J., 264.Warnell, J. L., 230.346.131.231.Warnhoff, E. ?V., ?GO.?Varren, D. R., 33.Warren, L., 335, 337, 338.Warringa, M. G. P. J., 318.Wartenpfuhl, F., 131.Wartik, T., 100.Waser, J., 113.Waser, P., 253.Waser, P. G., 261.Wasif, S., 151.Wasser, P. G., 209.Wasserman, H. H., 241.Watanabe, E., 180, 204.Watanabe, W. H., 200.Waterman, H., 144.Waters, W. A., 50, 152,Watkin, D. A. M., 236.Watkins, J. M., 54.Watson, D., 110.Watson, D. H., 169.Watson, J. S., 41.Watson, R. H., 39.Watson, R. W., 301, 302.Watt, G. W., 132, 143.Watts, T. H. E., 187.Waugh, J.S., 14, 15.Weaver, H. E., 44.Weaver, J. M., 337.Weaver, O., 210.Webb, J. R., 358.Webb, J. S., 241.Webb, R. L., 55.Weber, H., 117.Weber, J., 7.Weber, J. R., 45.Weber, M. W., 309.Weber, R., 124.Webster, A. H., 46.Webster, D. E., 150.Webster, G. C., 307, 314,Webster, J. A., 167.Weed, L. L., 330.Weedon, B. C. L., 205,Wehrmuller, J. , 292.Weigel, W., 103.Weil, K. G., 25.Weill, C. E., 188.Wein, J., 291, 292.Weiner, R., 360.Weingarten, H. I., 1’14.Weinhouse, S., 349.Weinmann, E. O., 313.Weinstock, B., 142.Weis, C., 166.Weise, E., 131.Weise, W., 255, 256.Weisenborn, F. L., 255,Weiser, D., 305.Weiser, K., 80.Weisiger, J. R., 346, 347.Weiss, F. T., 376.Weiss, G., 146.169.315.206, 207.258IKDEX OF AUTHORS’ NAMES.41 5I!eiss, €1. G., 228.Weiss, J., 57, 63, 64, 66,Weiss, K., 169.Weiss, M. J., 241.Weisser, H., 361.Weissman, S. I., 10, 11,Weisz, E., 288.Welch, C. M., 370.Weldes, H., 235.Welicky, N., 239.Wellman, R. E., 35.Wellman, W. W., 88.Wells, C. F., 48, 140.Welsh, H. K., 88.Weltner, T i . , 104.Welvart, Z., 287.Wendel, I., 215.Wender, I., 189.\17endlandt, h i . W., 130.Wendler, N. L., 175, 263,Wendolkowski, W. S., 119.Wenham, A. J. M., 230.Wenkert, E., 178, 184,Wentorf, R. H., 97.Wentworth, W. E., 354.Wepster, B. M., 149, 156,Werkema, T. E., 59.Werner, A. E. A., 225.Werner, I., 320, 321, 322,Werner, L., 325.Werner, R., 126.Werst, G., 247.Wertz, J. E., 10, 12, 15,West, I-’. W., 358, 370,West, R., 119.Westerhof, P., 272.liesterman, L., 124.Westermark, H., 77.Westheimer, F.H., 308,Westland, G. J., 94.Westlund, L. E., 279.Weston, M., 38.Weston, R. E., 35.Westrum, E. F., 71.Wessely, F., 200.Wettstein, A., 264, 267,Weygand, F., 196, 291,Whaley, H. A., 206.Whalley, E., 35, 81.Whalley, W. B., 254.Wheatley, P. J., 98, 100.Wheeler, C. M., 70.Wheeler, 0. H., 187, 264.Whiffen, D. H., 293.Whistler, R. L., 297, 298.67, 69, 70, 71, 141.44.264, 267.255, 258.157, 186.328.104.381.309.275.321, 323.TVtiitcutt, J. M., 305.White, A. G., 78, 136.White, A. M. S., 187.White, D., 367.White, D. E., 221.White, D. M., 220.White, J. F., 380.Whitehead, C. W., 340,Whitehurst, A., 104.Whitehurst, J.S., 230.Whitford, W. R., 192.Whiting, M. C., 76, 149,163, 192, 198, 200, 204.Whitman, C. I., 96.Whitman, G. M., 238.Whitson, J., 165.Whittaker, B., 65.Ifriberg, E., 97, 104, 109,Wiberg, K. B., 212.Wick, M., 189.Widmark, G., 216.Wiebenga, E. H., 113.Wiegers, G. A., 11 3.Wieker, W., 111.Wieland, P., 275.Wieland, T., 277, 286, 287.?Viemann, M. J., 211.Wiener, R. N., 110.Wiesendanger, €1. T i . D.,Wiesner, K., 260, 262.Wieters, E., 256.Wijnen, M. H. J., 37.Wilde, K. A., 35.Wildi, B. S., 347.Wilen, S. H., 169.Wiley, D. W., 75, 149.Wiley, P. F., 210, 239.Wilhelm, M., 180, 185.liilke, G., 183.Wilke, TV., 7.Wilkie, H., 37.Wilkins, C. N., 338.Wilkins, R. G., 42, 121,Wilkinson, F., 31.Wilkinson, G., 13, 74, 95,Wilkinson, J., 64.Wilkinson, R. W., 68.Willard, J. E., 33, 52, 66,Willemart, A., 199, 20U.\Villersinn, C.-H., 247.Williams, A. A., 127, 145.Williams, A. F., 385.Williams, F. V., 178, 228.Williams, G., 156.Williams, G. A., 14.Williams, G. H., 166, 167,Williams, K. D., 83.Williams, M. J . G., 122.Williams, M. Id., 89.341.229.44, 122.122.125, 189.151.168, 211.Williams. M. hi., 72.Williams, R. A., 164.Williams, R. E., 258.Williams, R. L., 108.Williams, R. R., 166.Williams, S. L. R., 63.Williams, T. F., 57, 68, 69.Williams, W. D., 230.Williamson, F. S., 51.Williamson, J. F., 76.Williamson, R., 156.IVilliamson, W. R. N., 252.Willson, S. D., 282.IVilmshurst, B. R., 73.Wilputte-Steinert, L., 159.Wilson, A. N., 203, 242,Wilson, D. J., 30, 33.Wilson, D. TT’., 329, 330,Wilscn, E. B., jun., 8, 14.Wilson, I;. C., 124.Wilson, I. B., 310.Wilson, J. W., 178.Wilson, M. K., 107.Wilson, R. A. L., 175, 191,Wilson, W., 224.Winder, F., 249.Winkelmann, G., 130.Winkhaus, G., 117.Winkler, R. E., 75, 149.Winslow, E. H., 67.Winslow, F. H., 57.Winslow, G. H., 82.Winslow, J. W., 86.Winstein, S., 159, 160,161, 164, 171, 172, 231.Winterfeld, E., 255.Wintermeyer, U., 277.Winternitz, F., 268.IVintersteiner, O., 274, 305.JVinzler, R. J., 313, 319,Wirth, H. F!., 88.liirzm~ller, A., 129.Wise, H., 34.TVitte, J., 182.Witten, B., 376.Witham, G. H., 200.Iiitham, G. J., 200.\iitltop, H., 176, 243, 277.Wittig, G., 233, 235, 246.Witz, S., 100.Wladislaw, B., 207.Woessner, D. E., 12.Wolf, C. F., 241.Wolf, D. E., 203.Wolf, H., 115.Wolf, J. R., 185.Wolfenden, J. H., 120.Wolford, L. T., 248.Wolinslry, J., 17 1.Wolochow, H., 312.Wolovsky, R., 198.Wolter, H., 320.274, 349.336.262.328416 INDEX OF AUTHORS’ NAMES.Woo, P. W. K., 305.Wood, A. J., 383.Wood, G. W., 182.Wood, H. C. S., 249.Wood, J. C., 276.Wood, J. L., 52.Wood, R. E., 89.Woodgate, P. R., 137.Woodger, R., 224.Woodhead, J. L., 134.Woods, K. R., 283.Woodward, A. E., 47, 58.Woodward, R. B., 210,Woodworth, R. C., 177,Woolf, A. A., 108.Woolley, D. W., 285.Work, T. S., 225.Worrall, I. J., 103.Worrall, R., 59, 67, 106.Worsfold, D. J., 59.Wotiz, J. H., 187, 212.Wren, J. J., 213.Wright, L. D., 203, 204,Wright, R. S., 301, 303.Wrigley, T. I., 175, 189,265, 266.Wu, R., 330.Wiinsch, E., 287.Wursch, J., 203, 275.Wiist, W., 256.Wuhrmann, J. J., 99, 102.Wunderlich, D., 247.Wunderlich, J. A,, 96.Wustrow, J. H., 311.Wyckoff, M. M., 279.Wynberg, H., 274.Wynne-Jones, W. F. K.,Wystrach, V. P., 239.Wyszomirski, E., 116.Wyttenbach, C., 314.Yajima, H., 260.Yamada, S., 128, 143.Yamakawa, T., 320, 325.Yamamura, S. S., 362.347, 350, 352.189.330.23, 24, 25.Yamana, S., 297.Yamasaki, R. S., 17.Yamashita, S., 50.Yamashina, I., 325.Yanari, S., 315.Yang, N. C., 217.Yang, J. T., 184.Yang, J. Y., 55.Yanitskii, I. V., 117.Yarembash, Ye. I., 96.Yasinkene, E. I., 51.Yasunobu, K., 310.Yates, R. A,, 332.Yatsimirskii, K. B., 51.Yefinov, E. A., 19.Yen, C. Y., 330.Yeoman, F. A., 136.Yoe, J. H., 374.Yoffe, S. T., 191.Yoho, C. W., 206.Yokohata, A., 49.Yoshida, S., 225.Yost, D. M., 12.Youhotsky-Gore, I., 203,Young, A. E., 95.Young, G. T., 289.Young, H. L., 156.Young, J. A., 74.Young, J. R., 148.Young, L., 21, 28.Young, R. L., 184, 187.Young, W. G., 163.Yudkin, J., 318.Yuen Chu Leung, 113.Zahner, H., 249ZabXova, A., 204.Zachariasen, W. H., 138.Zacharius, R. M., 276.Zachau, H. G., 244.Zager, W. T., 89.Zagt, R., 161.Zahlan, A. B., 66.Zahler, R. E., 154.Zakharin, L. I., 267.Zaki, M. R., 371.Zalichi, D. T., 165.Zall, D. M., 373.275.Zambura, Z., 23.Zamecnik, P. C., 314.Zamith, A. A. L., 118.Zander, M., 229.Zange, E., 115.Zaoral, M., 289, 291.Zaromb, S., 87.Zaslavskii, I., 24.Zatman, L. J., 308.Zauli, C., 145.Zavitsanos, P., 107.Zaweski, E. F., 213, 237.Zbiral, E., 200.Zderic, J. A., 186.Zechmeister, L., 203, 204.Zechner, S., 380.Zeelenberg, A. P., 35.Zeile, K., 254.Zeiss, H. H., 129, 130, 221,Zeldes, H., 12.Zelionkaite, V. I., 117.Zeller, P., 201, 202, 209.Zemplh, G., 296.Zengin, N., 87.Zhigach, A. F., 99.Zhilenkov, I. V., 90.Ziegler, K., 98, 102.Ziegler, M., 370, 372, 374.Ziegler, P., 270.Zihlman, F. A., 83.Zilliken, F., 320, 328.Zimm, B. H., 56.Zimmerman, H. E., 175,Zimmerman, J. R., 12.Zimmerman, R. L., 59.Zimmermann, J. P., 292.Zinsmeister, R., 240.Zirngibl, L., 233.Zlamal, Z., 59.Zollinger, H., 154, 155.Zsula, J., 64.Ziist, A.. 253.Zuur, A. P., 102.Zvorykin, A. Ya., 47.Zvyagintsev, 0. Ye., 139.Zwahlen, K. D., 211.Zweifel, G., 293.239.176

ISSN:0365-6217    

DOI:10.1039/AR9575400387

出版商:RSC    

年代:1957

数据来源: RSC

摘要:

INDEX OF SUBJECTS.Absorption spectroscopy, 369.Acetaldehyde, dimensions of, 8.oxidation of, by peracetic acid, 49.Acetamide, radical from, 11.NN-dimethyl-, configuration of, 13.Acetate as precursor of antibiotics, 350.Acetate radical, heat of formation of, 72.-4cetic acid, irradiation of solutions of,68.Peracetic acid, oxidation of acetalde-hyde by, 49.Peroxyacetic acid, anhydrous, prepar-ation of, 190.trans-4-Acetox ycycZohexanecarboxylicacid, methyl ester, formation of, 173.Acetyl peroxide, heat of formation of, 72.Acetyl tetrafluoroborate, 99.Acetylandromedol, identity of, withAcetylene irradiation of solutions of, 67.Acetylene complexes with transitionmetals, 127.Acetylenes, 197.Acids, fatty, 205.grayanotoxin and rhodotoxin, 228.gas-liquid chromatographic separ-ation of, 369.Acid-base equilibria, 50.Acraldehyde, oxidation of, by manganicAcridine, action of benzyl radicals on, 169.Acridinium salts, reaction of, with activemethylene compounds, 249.Acrylonitrile, polymerisation of, 56.Actinomycin C,, D-amino-acids in, 347.Actinomycins, 250.A4cylating agents, dtmn.of, 376.Acylation, 155.Adamantane, preparation of, 215.Adipic acid, chromatographic separationof, 367.Adsorbed molecules, 90.Ascigenin, structure of, 226.Affinin, identity of, with spilanthol, 207.Ajaconine, 260.Alantolactone, structure of, 220.Alcohols, dtmn. of, 359.Aldehydes, a-keto-, preparation of, 196.a/3-unsaturated, preparation of, 195.Aldolase, 317.Alicyclic compounds, 212.Aliphatic compounds, 197.Alkali metals in liquid ammonia, modelfor, 95.Alkaloids, 254.pyrophosphate, 50.irradiation of solution of, 67.steroidal, 273.Alkyl substituents, effect of, on heats ofAlkylation, 155, 194.Allene radical, 200.Allenes, 200.Alloys, thermochemistry of, 81.Ally1 anions, stereochemistry of, 184.Allylic carbanion, conformation of, 2 12.Aluminium, calorimetric dtmn.of, inbrasses and bronzes, 370.dtmn. of, in presence of iron andchromium, 360.passivation of, 25.hydrogenation of olefins, 75.of benzene derivatives, 228.Aluminium, triethyl-, reaction of, with di-cyclopentadienyltitanium dichloride,102.Aluminium bromide, bromine resonancein, 16.Aluminium chloride-carbon yl chloride, ex-change of chloride, 102.Aluminium trichloride, compounds of,with phosphorus oxychloride, 102.Americium, valency states of, 137.Amides, energies and entropies ofAmines, aliphatic, photometric dtmn.of,Amino-acids, 276." Aminoacyl Einlagerung," 292.Amino-sugars, 304.y- and 8-Aminovaleric acid, synthesis of,Ammonia, decomposition of, induced byAmmonia molecule, exchange of, 122.Ammonium dichromate, heat of formationAnabasine, A2-tetrahydro-1 : 1'-dimetliyl-,formation of, 245.Analytical chemistry, 353.Anibine, structure of, 256.Anionotropic rearrangements, 163.Annotinine, structure of, 262.Anthracene, action of benzyl radicals on,Anthrasteroid rearrangement, 269.Antibiotics, aromatic, biosynthesis of, 350.Antimony, photometric dtmn.of, 373.Antimony analogues of aniline and di-Tetrachloroantimony fluoride, form-Trifluoromethyliodostibin es, 1 15.Alumina, heat of formation of, 74.molecular association of, 79.376.277.a-particles, 66.of, 80.169.dtmn. of, 377.phenylamine, 109.ation of, 115.REP.-VOL. LIV 41 7 418 INDEX OF SUBJECTS.Antioxidants in petrol, dtmn. of, 365.Aphyllidine, structure of, 255.(A)-Aphylline, 255.Apparatus, analytical, 384.Aqueous soh tions, radiation chemistry of,Arctiolide, structure of, 219.Aromatic complexes with transitionAromatic compounds, 228.pseudo-Aromatic systems, 234.Arrhenius parameters of free-radical re-actions involving organic com-pounds, 36.of homogeneous elementary reactionsin inorganic systems, 32.64.metals, 128.Arsenic, colorimetric dtmn.of, 374.Arsenic analogues of aniline and diphenyl-amine, 109.Diarsine, 108.Hydroxyfluoroarsenic acid, potassiumsalt, 114.Tetrafluoroarsenates, 114.Artemisetin, structure of, 252.cycZoArteno1, identity of, with /I-orysterol,Arylazotriphenylmethanes, decompos-Ascortigen, structure of, 247.Aspidin, structure of, 226.Aspidospermine, structure of, 269.Astatine, oxidation of, 121.Rstatophenol, formation of, 121.Athamantin, structure of, 253.Aureothricin, biosynthesis of, 346.Azaoctatetraenes, tri- and tetra-, 246.Azaphilones, 254.Azelaic acid , chromatographic separationof, 368.Rzepines, 252.Azide ions, decomposition of, by X-rays,Azides, photometric dtmn. of, 373.Aziridine, I-ethyl-2-methyl , 208.Azo-compounds, direct titration of, 364.Azoles, 242.Azulene, resonance energy of, 75.Azulenes, 235.test for, 355.225.ition of, 166.65.Bzcitracin, amino-acids in, 347.Eaptifoline, structure of, 255.Barium, dtmn.of, in zirconyl chloride andBasic functional groups, titration of, 361.Beckmann rearrangement of steroidBelladine, structure of, 260.Benzene, irradiation of solutions of, 67.biosynthesis of, 346.zirconium, 357.oximes, 269.isomerisation of, to fulvene, 228.pentafluoro-, formation of, 228.Benzene derivatives, alkylation of, 228.Benzocyclobutadiene, 235.“ Benzocyclobutadienequinone,” 235.Ren zodithioph en, form atinn of, 240.Benzofurans, alkyl-, 246.Benzoic acid, heat of combustion of, 72.formation of, 81.Ben zocy dopol yenes , 2 35.Benzoxazolones, 6-methoxy-, in maize,Benzoyl chloride as ionising solvent, 105.N-Benzoyldiphenylamine-2-carboxylicBenzoyl bromide, heat of formation of,Benzyl radicals, reactions of, 169.Benzyne intermediates, 233.Berkelium(rv), separation of, 138.Beryllium, dtmn.of, 357.Beryllium amalgam, preparation of, 96.Beryllium oxynaphthoates, 96.Bile acids, 270.Bimolecular substitution at a saturatedcarbon atom, 162.Biological chemistry, 306.Bismuth, absorptiometric dtmn. of, 372.Borazens, formation of, 101.Boron, absorptiometric dtmn. of, 375.248.acids, conformation of, 180.77.micro-determination of, 37 1.dtmn. of, 358.in nickel, 374.traces of, 354, 372.tributyl- and triethyl-, as initiators intrimethyl-, decomposition of, 101.tri-n-propyl-, formation of, 98.Boron hydrides, 97.nitride, 97.phosphide, 97.trichloride, addition compounds of, 101.Boron trichloride-carbon monoxide poly-mers, 100.Boron trifluoride, reactions of, 99.Boron trifluoride-ether complex, catalysisof polymerisation by, 59.Boron-nitrogen compounds, new class of,99.Alkylboronic anhydrides, preparationof, 101.Alkylborons, 193.Dibxane, bridge-breaking energy of, $9.preparation of, 98.Diborane as reducing agent, 188.Diboron tetrachloride, configuration of,100.Dimethylboryl methyl peroxide, 101.Disilylaminoboron difluoride, 100.Fluoromethylboron difluoride, 100.Tetraborane diammine, 98.polymerisation, 60.Bottromycin, biosynthesis of, 346.Bromine pentafluoride, structure of, 119.trifluoride, dimensions of, 8.structure of, 119.-bromine system, 120.Bromide ion, oxidation of, by nitricacid, 51.Bromides, chromatographic separationof, from chlorides and iodides, 366.Tetrafluorobromite ion.strilcture of,120INDEX OF SUBJECTS. 4192~-Bromolanostan-3-one, conformation of,Burette of high accuracy, 384.cycZoButanes, bisdiarylmethylene-, 2 13.cycZoButanone, photolysis of, 40.isoButene, polymerisation of, 59, 61.But-2-ene, rate of isomerisation of, 58.tert.-Butyl hydroperoxide, decompositionn-Butyl phosphate, electron irradiation of,Butyrate radical, heat of formation of, 72.Butyryl peroxide, heat of formation of, 72.Cadmium, dimethyl-, bond dissociationCadmium sulphide, m.p. of, 145.Czsium, radic-chemical dtmn. of, 383.epzCalcifero1, 270.Calcium, complexometric titration of, 360.direct titration of, in presence ofmagnesium, 359, 360.volumetric dtmn. of, 378.Camphenilanic acids, configurations of,217.Canthaxanthin, 203.Capsanthin, reformulation of, 202.Capsorubin, reformulation of, 202.Carbohydrates, 292.esters of, 300.mutarotation of, 297.oxidation of, 294.phosphates of, 300.stereochemistry of, 292.Carbon, latent heat of evaporation of, 82.micro-dtmn. of, in organic compounds,monatomic, heat of sublimation of, 82.vapour of, composition of, 82.Carbon and carbon compounds, dtmn. of,Carbon dioxide, decomposition of, byCarbon monoxide, electronic structure173.of, 49.68.energies in, 81.378.in bromine, 381.ionising radiation, 66.dtmn.of, in water, 381.of, 9.heat of dissociation of, 82.Carbon tetrachloride, heat of formationCarbonyl chloride-aluminium chloride, ex-Carbonyl compounds, 195.Carbonyls, 124.Carboxylases, 316.Carboxylic acids, 196.A3-Carene, reactions of, 216.Carotenoids, 200.Catalysed reactions, homogeneous, 46.Catechin derivatives, 253.Cativic acid, structure of, 221.Cellulose, bacterial, dtmn. of, 379.“ Centaur X3,” structure of, 197.Cerium(Iv), spot-test for, 381.Chalinwterol, structure of, 269.of, 77.change of chloride, 102.Ceric perchlorate, oxidation of ethanolby, 49.Chamic acids, 216.Chanoclavine, structure of, 260.Chloramphenicol, biosynthesis of, 348.Chlorbenside, assay of, 381.Chlorine, micro-determination of, 379.quadrupole resonances in, 16.Chlorides, chromatographic separationof, from bromides and iodides, 366.Perchloryl fluoride, properties of, 119.irradiation of, 70.reactions of, 267.24-methylene-, synthesis of, 269.Chromatography, 365.Chromium, dtmn.of, in presence of ironand aluminium, 360.zero-charge potential on, 27.Chromium hexacarbonyl, 124.Chromic acid solutions, aqueous,Chromous iodide, heat of sublimation of,Dibenzenechromiuni cation, fine struc-Hypochromate ion, CrOd3-, 134.“ Perchromic acid,” structure of, 134.Cholesterol, biosynthetic, 275.thermal decomposition of, 134.82.ture of, 10.Chrysene, synthesis of, 229.Chy mo trypsin, 3 10.Cinnabarin, structure of, 250.Circumanthracene, 229.Cleavage, point of, in biological systems,Cobalt, colorimetric dtmn.of, 374.radiochemical dtmn. of, 383.univalent, formation of, 139.Cobalt(m), acetate, 139.Cobalt carbonyl anion, compounds of, 126.Cobalt carbonyls, derivatives of, 126.Cobalt (111) complexes with phosphateCombustion method, new, 378.Complexones, uses of, 359.Conformational analysis, 170.“ Conformational transmissicn,’ ’ 174.Copper, colorimetric dtmn. of, 370.310.group, 140.anomalies, 173.control in unimolecular reactions, 159.complex ions of, with bromine, 145.complexometric dtmn. of, in presence ofmercury, 360.overvoltage of, 26.radio-chemical dtmn. of, 383.reductometric titration of, 362.spectrometric dtmn.of, 373.zero-charge potential on, 27.Copper acetylacetone, anisotropic g-factorCopper nitrate, anhydrous, 144,Copper porphin derivatives, resonance in,Cuprocyanide ion, crystal structure of,Cuprous chloride, infrared spectrum o f ,in, 10.10.144.144.Coronene, formation of, 229.Corticotropins, structure of, 282420 INDEX OF SUBJECTS.Corynoxeine, structure of, 258.isocoumarin, ( -) -3 : 4-dihydro-8-hydroxy-6-methoxy-3-rnethy1, in bitter car-rots, 252.Crocetin diesters, 202.Cryptopleurine, synthesis of, 262.Cryptoxanthin, preparation of, 201.Cucurbatins, 227.Curium(1v) fluoride, 138.isocyanate, colorimetric test for, anddtmn. of, 376.Cyanic acid, hydrolysis of, 50.Cysteine, irradiation of, 70.Dalbergin, U-methyl-, structure of, 252.Darutigenol, 222.Dehydrases, 312.Dehydrogenases, 312.17-Demethoxydeserpidine, synthesis of,Dendrolasin, structure of, 215.Deoxyribonucleic acid, irradiation of, 70.Depolymerisation, 57.Desaspidin, structure of, 226.Deserpidine, 17-demethoxy-, synthesis of,Deutero-compounds, optically active, 185.Diacetylenes, terminal, oxidative couplingDiacyl peroxides, thermal decomposition“ Diatretyne 11,” 197.Diazines, 245.Diazo-coupling, 155.Diazonium salts, 234.Dibenzenechromium cation, fine structuretrans-1 : 2-Dibromocyclooctene, 182.1 : 2-Dichloroethylene, cis- and tram-,Dielectric measurements, 83.Diels-Alder reaction, retrogressive, use of,Diethyldithiocarbamates, analytical use(o-Diethylphosphinophenyl) diethylarsine1 : 4-DimethylcycZohexane, autoxidationDinoronocerane, 222.Dioscorine, structure of, 255.Dioxans, 2 : 3-disubstituted, formation of,243.Dicyclopentadienyltitanium dichloride, re-action of, with triethylaluminium,102.Diphenyls, non-planar, configuration of,179.Displacement of groups other than hydro-gen, 154.Diterpene alkaloids, 260.Diterpenes, 221.p-Dolabrin, occurrence of, 237.Dosimetry, 63.Drimenol, structure of, 220.Drosophilin C, structure of, 197.258.258.of, 198.of, 166.of, 10.interconversion of, 52.211.of, 357.as ligand, 144.of, 47.Eburicoic acid, biosynthesis of, 276.Echinomycin, 249.tyans.-Effect in platinum complexes, 122.a-Elaterin, formula of, 227.Electrical double layer, the, 26.Electrical methods of analysis, 362.Electrochemistry, 17.Electron-exchange reactions, 42, 43, 45.Electron resonance, 9.Electrophilic aromatic substitution, 151.Emetine, partial configuration of, 256.Emission spectroscopy, 377.Enniatins, structure of, 285.“ Entrainment,” resolution of a-amino-Enzymes, action of, 306.Eperuic acid, structure of, 221.ErFosterol, biosynthesis of, 276.Eriochrome-black T, uses of, 371.Eschscholtzxanthin, formation of, 202.Esters, /3-keto-, preparation of, 196.Ethane, 1 : 1 : 2 : 2-tetrachloro-1 : 2-di-fluoro-, configuratiqn of, 13.Ethanol, action of X-rays on solutions of,68.oxidation of, by ceric perchlorate, 49.radical from, 11.acids by, 278.hydrolytic, 310.oxidative, 309.Ethyl iodide, liquid, photolysis of, 166.Ethyl radical, configuration of, 177.Ethylene, absorption of, by sulphuricirradiation of aqueous solutions of, 67.tetracyano-, reactions of, 209.Ethylene oxide, acid-catalysed hydrolysispolymerisation of, 59.Ethylene oxides, conformation of, 174.Ethyl-lithium, preparation of, 192.( -) -a-Ethylapopinene, isomerisation of,Ethynylmagnesium bromide, use of, 192.cycZoEucaleno1, structure of, 224.Europium, solution of, in ammonia, 131.Exchange reactions, biological, 307.bicycZoFarnesic acids, 223.Fast-grey RA, uses of, 370.Favorski reaction applied to steroids, 268.Feist’s acid, cis-isomer of, 212.Ferrocene, reduction of, 129.Ferrocenes, 237.Ferrocenyl aliphatic acids, 239.a-Ferrocenylbenzyl alcohol, O-methyl-(f)-Ferruginol, synthesis of, 222.Filixic acid, structure of, 226.Flavopereirine, structure of, 257.Flavothiophen, 229.Fluorbenside, assay of, 381.Fluoride, amperometric titration of, 365.Fluorides, test for and dtmn.of, 366.Fluorine, dtmn. of, in organic compounds,acid, 52.of, 51.217.ation of, 238.378.Hydrogen fluoride as solvent, 118INDEX OF SUBJECTS. 421p-Fluorobenzoic acid, as reference sub-stance in calorimetry, 73.Formamide, dimensions of, 8.Free radicals, stable, 165.Free-radical intermediates, 166.Fulvene, formation of, from benzene, 228.Fulvic acid, structure of, 253.Furans, 241.Galanthamine, structure of, 260.Gallium dichloride, structure of, 102.trichloride, properties of, 103.NN-dimethyl-, configuration of, 13.compound of, with phosphorus oxy-chloride, 103.Gas-phase kinetics, 30.Gas-phase oxidation systems, 41.Geigerin, structure of, 220.Gelatine, irradiation of, 70.General and physical chemistry, 7.Germacrol (now germacrone), structure of,Germacrone, structure of, 219.Germane, preparation of, 107.Germanium, polarographic dtmn.of, 364.Germanium monoxide, non-existence of,Gliotoxin, biosynthesis of, 346.Glucagon, structure of, 282.Glucose, irradiation of solutions of, 70.Glutathione, synthesis of, 291.Glycerophosphatides , beef-liver, 205.Glycols, chromatographic separation of,Glyoxalase, 317.Glyoxaline, 4 : 5-dihydro-5-oxo-, form-Gold, dtmn. of, in sea-water, 383.219.test for, 355.107.368.ation of, 243.Aurate ion, 145.Aurocyanide ion, structure of, 145.-S, amino-acids in, 347.Gramidicin- J, amino-acids in, 347.synthesis of, 288.Graphite, lamellar compounds of, 104.Graphite oxide, 104.Gravimetric analysis, 356.Grignard reagents, chemistry of, 191.structure of, 212.Grisen, dioxo-, 254.Griseofulvin, biosynthesis of, 253.Group-transfer reactions, biological , 307.Guaiazulene, oxidation of, 236.Halides, spectrophotometric dtmn.of, 375.Halogenation, 152.Heat of combustion, 71.Helenalin, 221.Heliopsin, 207.Heptafulvalene, resonance energy of, 75.Heptafulvene, resonance energy of, 75.Hept-2-yne, l-iodo-, reaction of, withneoHerculin, identity of, with a-sanshool ,Heteroauxin, reaction of, with ozone, 247,nickel carbonyl , 200.207.Heterocyclic compounds, 239.Heterogeneous reactions , stereochemistryHeterometric titrations, 371.Hexamethylditin, heat of reaction withcycZoHexane, 1 : 4-dimethyl-, autoxidationbicycZo[3 : 1 : OIHexane-l-carboxylic acid,methyl ester, preparation of, 214.cycZoHexanone, photolysis of, 40.bicycZo[3 : 1 : O]Hexan-2-one, preparationHexaphenylene, preparation of, 233.cycZoHex-2-eno1, oxidation of, 174.Hexitols, etc., fully nitrated derivatives of,Holmium oxide, heat of formation of, 131.monocycZoHomofarnesic acids, cyclisationHomolytic aromatic substitution, 168.Homolytic reactions, 165.Hopanone, hydroxy-, structure of, 225.Hydrazinetetrasulphonic acid, tetra-Hydrazinophthalazines as colorimetricHydrocarbons, halogenated , micro-deter-volatile, dtmn.of, in trade effluents, 353.Hydrogen, micro-determination of, inin organic compounds, 378.Hydrogen-abstraction reactions, 169.Hydrogen-bonded systems, 86.Hydrogen peroxide, reaction of, withHydrogen selenide, dimensions of, 8.Hydrogenase, 328.Hydrogenation, catalytic, 186.Hydrolysis, 50.heats of, 77.Hydrolytic enzymes, 310.Hydroxides, alkali, dtmn. of, 358.o-Hydroxyacetophenone oxime, analytical2-Hydroxydiphenyl, dtmn. of, 377.y-Hydroxyproline, synthesis of, 277.Hyperconjugation, 149.Hypericins, 231.Hypertensins, structure of, 283.Ibogaine, structure of, 259.Ibogamine, structure of, 259.Ice, dielectric relaxation process in, 87.Icthiamine, structure of, 245.Iridazoles, preparation of, 248.Indium, dtmn. of, in rocks and minerals,Indium borohydride, 104.Indium hydrides, 104.Indium iodides, 104.Indium lithium hydride, complex of,with ether, 104.Indole alkaloids, 257.of, 178.bromine and with iodine, 77.of, 47.of, 214.304.of, 224.potassium salt, 109.reagents, 370.mination of, 384.metals, 380.ferrous ion, 48.uses of, 356.synthesis of, 289.383422 INDEX OF SUBJECTS.Indoles, 246.Influenza virus, blood-cell receptor for, 326.Inorganic chemistry, 93.Insulins, structure of, 282.Iodide, coulometric dtmn.of, 362.Iodides, chromatographic separation of,from chlorides and bromides, 366.Iodide ion, positive, 121.Iodine, quadrupole resonance of, 17.Iodine heptafluoride, structure of, 120.Iodine trichloride, iodine resonance in, 17.l-Iodohept-2-yne, reaction of, with nickelIon-exchange membranes, use of, inpseudoIonone, synthesis of, 204./3-Ionone, irradiation of, 217.Iresin, structure of, 220.Iridium strontium oxide, 140.Iron, colorimetric dtmn.of, 370.carbonyl, 200.analysis, 354.dtmn. of, in presence of aluminium andchromium, 360.electrochemical dtmn. of, 362.passivation of, 25.polarimetric dtmn. of, 354.separation of, from magnesium, 382.test for trace amounts of, 355.Iron carbonyls, reactions of, 125.Iron dodecacarbonyl, 125.Ferric iodides, 139.Ferrous bromide hydrates, 139.Ferrous ion, reaction of, with hydrogenperoxide, 48.Isatin blue, formulation of, 247.Isomerases, 315.Isoprene, polymerisation of, 61.Isotopic exchange reactions, 44, 151.Junenol, structure of, 220.Katonic acid, structure of, 226.Kessoglycol, structure of, 221.Kessyl alcohol, structure of, 221.Ketens, photolysis of, 40.Keto-enol reactions, stereochemistry of,175.“ Ketone 104,” structure of, 266.Kinases, 313.Kinetics of chemical change, 30.Kojic acid, biosynthesis of, 349.Lactaroviolin, synthesis of, 236.Lactobacillic acid, structure of, 207.y-Lactones, irradiation of, 70.Lanostan-3-one, 2/3-bromo-, configurationLanthanide nitrides, 130.Lead, absorptiometric dtmn. of, 375.micro-dtmn.of, 371.passivation of, 23.Lead carbonate, basic, a new, 108.Lead dioxide, electrochemically formed,structure of, 24.I-Iexa(hydrogen su1phato)plumbic acid,108.of organic systems, 35.of, 173.Ligand-field theory, 93.Limonin, structure of, 227.Lithium aluminium hydride, use of,Lithium indium hydride, complex of,Lithium tri-tert.-butoxyaluminium hydr-o-Dilithiobenzene, preparation of, 233.Lochnerine, structure of, 259.Loganin, structure of, 216.Lumazine, lactam form of, 249.Limichrome, formation of, 249.Lumisantonin, structure of, 217.Lupinane alkaloids, 255.Lysine-vasopressin, synthesis of, 289.hlaaliane, cleavage of, 220.Maalilol, structure of, 220.Macrolides, 210.Magnamycin, biogenesis of, 351.Magnesium, dtmn.of, by flame photo-in presence of calcium, 359.organic compounds of, 191.(See also Grignard reagents.)separation of, from iron, 382.Magnesium hydride halides, 96.Manganese, oxidations by various oxidesManganese carbonyls, 125.Manganese group, 138.Manganese pentacarbonyl hydride, 125.cis : cis-Matricaria ester, lactonisation of,Matrine and domatrine, stereochemistryMedicagenic acid, structure of, 225.Melionine-B, structure of, 257.Mercury, colorimetric dtmn.of, 374.186.with ether, 104.ide as a reducing agent, 264.biogenesis of, 351.metry, 378.of, 50.198.of, 256.complexes of, 146.complexometric dtmn. of, in presenceof copper, 360.dissolution of, a t very low currentdensities, 23.solubility of, in water, 146.Mercury(II), spot test for, 380.Mercury(I1) cyanide, structure of, 146.Mercury(I1) oxide, structure of, 146.Mercurous chloride, anodically formed,ion, disproportionation of, 145.Mercury, diethyl-, radicals from, 1 1.dimethyl-, bond dissociation energiesstructure of, 23.in, 81.radicals from, 11.Vinylmercury compounds, 194.Metal electrodes, deposits on, 21.Metal ions, oxidations by, 49,Metals, reduction by, 188.Methaemoglobin, acid, g-factor in, 10.Methane, irradiation of, 66.Methanol, radical from, 11.[35S]~~-Methionine, self-irradiation of,70INDEX OF SUBJECTS.423c is-3-MethoxycycZohexanecarboxylic acid,conversion of, into methyl trans-4-acetoxycydohexanecarboxylate, 1 7 3.Methyl trans-4-acetoxycycZohexanecarb-oxylate, formation of, 173.Methyl radical, configuration of, 177.Methylamine, structure of, 9.Methylene radicals, reactions of, withMethylene-blue, effect of X-rays on, 65.2-Methyloxazolidines, formation of, 200.Methylsilane, configuration of, S.a-Methylstyrene epoxide, conversion ~ f ,into acetophenone, 240.Mevaldic acid, preparation of, 204.Mevalonic acid as precursor of isopreneunits, 203.Micro-analysis, 378.Micrococcin P, biosynthesis of, 346.Mikanecic acid, structure of, 212.Molecular rearrangement in steroids, 267.Mollisacacidin, structure of, 253.Mollisin, structure of, 230.Molybdenum, dtmn.of, in titanium, 357.fluorides of, 135.oxalato-complex of, 135.oxides of, 135.paraffins, 40.degradation of, 243.Molybdenum di- and tri-oxide, heat ofBis(cycZopentadienylmo1ybdenum tri-formation of, 74.carbonyl) , 124.Monoterpenes, 2 15.Muramic acid, structure of, 305.Muscarine, structure of, 208, 261.Muscopyridine, synthesis of, 244.Mustard oils, natural, 209.Mutases, 315.Mycins, 210.structure of, 285.Mycolipenic acid, 205.Mycosamine, structure of, 305.Myrtillogenic acid, structure of, 225.Nalgiovensin, structure of, 230.Napellonine, structure of, 260.Naphthalene, negative ion of, spin-densi-ties in, 10.Naphthalynes, 233.Narwedine, structure of, 260.Nepetalic acids, stereochemistry of, 215.Neptunium, physical properties of, 137.Netropsin, structure of, 241.Neuraminic acid, 319.linkage of, to carrier molecules, 328.sources of, 325.structure of, 320.synonyms of, 320.ozonolysis of, 230.Neuraminic acid, N-acetyl-, synthesis andNickel, passivation of, 24.Nickel (11) bisacetylacetone, configurationNickel complexes, 140.degradation of, 323.radio-chemical dtmn.of, 383.of, 141.Nickel cyanide-ammonia-benzene clath-rate, decomposition of, 141.Nickelocene, proton resonance in, 13.Nimbin, structure of, 227.Niobium, separation of, 361.from tantalum, 355.Niobium dibromide, formation of, 133.pentachloride, physical constants of,reactions of, with aliphatic amines,133.133.pentaiodide, formation of, 133.Peroxy-niobium complexes, 133.Nitration, 151.Nitro-aromatic amines, titration of, 364.Nitro-compounds, direct titration of,Nitroethane, spot tests for, 356.Nitrogen, active, afterglow of, 12.heat of dissociation of, 81.micro-determination of, 379.Dinitrogen pentoxide, heat of formationof, 80.Dinitrogen tetroxide, structure of, 109.Dinitrogen trioxide, complex of, withboron trifluoride, 100.Hyponitrites, infrared spectrum of, 110.Nitrate, spot test for, 381.Nitrates, y-ray induced decompositionNitrato-complexes, 123.Nitric acid, oxidation of bromide by,Nitric oxide, decomposition of, byNitrilotrisulphonate ion, hydrolysis of,Nitrites, alkyl, configuration of, 13.Nitrogen dioxide, dimensions of, 8.Nitrosyl metasilicate, decomposition364.of, 68.51.fission fragments, 66.109.of, 107.Nitromethane, spot tests for, 356.Nitrosamines, hindered rotation in, 13.Nitroso-compounds, direct titration of,Nitrosylsonium, formation of, 110.Nobelium, formation of, 138.Norbixin diesters, 202.Nootkatene, 220.Nuclear magnetic resonance, 12.Nuclear quadrupole resonance, 16.Nucleophilic aromatic substitution, 156.substitution at a saturated carbonNudic acid B, identity of, with ‘‘ diatre-Nupharidine, structure of, 261.Nyctanthic acid, structure of, 224.Nylon and related polymers, identific-Occidentalol, structure of, 220.Octaphenylene, preparation of, 233.cycZoOctatetraene, resonance energy o f ,364.atom, 158.tyne 11,” 197.ation of, 367.75.ring contraction of, 236424 INDEX OF SUBJECTS.cycZoOctatetraene dimer, structure of,1 : 3 : 5-cycZoOctatriene, resonance energycycZoOctene, trans-1 : 2-dibromo-, 182.cycZoOctene oxides, solvolysis of, 182.Odyssic acid, 197.Odyssin, 197.Olefin complexes with transition metals,127.Olefins, reactivity of, towards free-radicalattack, 168.spectrophotometric titration of, 364.Ommochromes, 250.(+)-(8?,8S’)Onocerane-8 : 8’-diol, form-Orcein, a-, 8-, and y-amino-, structure of,Organic chemistry, 147.Organic substances, oxidative fission of,Organo-metallic compounds, 191.Orientation freedom in solids, 88.Orotic acid as growth factor, 330./l-OrysteroI, identity of, with cyclo-Osmium, colorimetric dtmn. of, 374.Osmium(v1) oxychloride, OsOC1,.139.Osmium(vzI1) oxyfluoride, OsO,F,, 139.Ostreasterol, structure of, 269.Oxazolidines, 2-methyl-, formation of,Oxetane, bischloromethyl-, reaction of,Oxidation, 189.Oxidative enzymes, 309.Oxides, anodic formation of, 21.Oxycelluloce as cation-exchange medium,366.Oxygen, dissolved, micro-determinationof, 380.dtmn.of, in organic compounds, 379.in titanium and its alloys, 356.evolution of, in anodic processes, 18.on cobalt, 18.micro-determination of, in metals,380.molecular, in oxidation, 189.reactions of, 47.215.of, 75.ation of, 224.251.theoretical, 147.356.artenol, 225.200.with sodium sulphide, 240.biological, 308.Oxygen heterocyclics, complex, 252.Oxygen isotopes, fractionation of, a tOxygen overvoltage, 18.Oxygen radicals, stability of, 165.Oxytocin, synthesis of, 289.Palladium, colorimetric reagent for, 369.Palladium, null-valent, 142.anodes, 19.complexes, 142.difluoride, preparation of, 142.Paper chromatography, 367.n-Paraffins, irradiation of, 67.“ Paramagnetic pulse ” reactions, 44.particle-size, dtmn.of, 382.Penicillin, biosynthesis of, 339.chart of possible metabolic pathwaysPenicillin V, synthesis of, 246.cycZoPentadienylthallium (I), formation of,Pentalenes, 235.bicycloC2 : 1 : OIPentane, preparation of,cycZoPentanone, photolysis of, 40.cycZoPent-4-ene-1 : 3-dione, synthesis of,Peptides, purification of, 278.Perfluorodimethyl peroxide, formation of,Perilla ketone, synthesis of, 241.Perinaphthene, radical from, 11.Perinaphthenyl radical, preparation of,Peroxides, oxidation by, 190.Peroxy-compounds, reactions of, 47.Phalloidin, structure of, 286.Phase transitions in solids, 88.Phenanthridine alkaloids, 260.Phenol, 2 : 4 : 5-trichloro- and 2 : 4 4 -Phenols, 231.of, 344.104.213.213.structural investigation of, 279.synthesis of, 287.119.165.chloro-, separation of, 368.dtmn.of, 377.formation of, from aromatic halides,from aryl halides, 231.193.4-PhenylcycZohexane-1 : l-dicarboxylicacid, decarboxylation of, 175.o-Phenylphenol, detmn. of, 377.Phloionolic acids, structure of, 207.Phosphine, phenyl-, formation of, 229.triphenyl-, deoxygenation of peroxidesPhosphines, tertiary, preparation of,Phosphorus, colorimetric dtmn. of, 374.Phosphorus, as Psc, micro-test for, 380.Phosphorus compounds, multiple bond-ing in, 110.Phosphorus hydride, P,H4, 108.Phosphorus in organic compounds, colori-metric test for, 370.Phosphorus oxychloride, compounds of,with aluminium trichloride, 102.Phosphorus oxyfluoride, P,O,,F,,, form-ation of, 113.Phosphorus pentachloride, ammonolysisof, 113.Phosphorus sulphides, structure of, 113.Hypophosphoric acid, structure ofesters of, 11 1.iso-, esters of, 11 1.Metaphosphates, 11 1.Organophosphorus compounds, test for,and dtmn.of, 376.Phosphine, silyl-, solvolysis of, 107.Phosphites, P-H bond in, 13.Phosphoramidic acid, thermal re-by, 189.193.arrangement of, 112INDEX OF SUBJECTS. 425Phosphorodiamidic acid, hydration of,Polymetaphosphorous acids, esters of,Polyphosphates, 110.Pyrophosphoryl chloride, reaction of,112.111.paper chromatography of, 365.with ammonia, 112.Phosphorylases, 312.Phosphorylating agents, dtmn. of, 376.Photochemical reactions of alicyclic com-pounds, 217." isoPhotosantonic lactone," structure of,217.o-Phthalates, test for, and dtmn.of, 376.Physical methods of analysis, 362.Physoxanthin, structure of, 203.neophytadiene, structure of, 204.Picrotoxin derivatives, 226.Pimelic acid, chromatographic separationof, 368.Piperidine, 4-hydroxy-1 : 2 : 2 : 6 : 6-penta-methyl-Pphenyl-, conformation of,173.Piperidines, 243.Platinum complexes, 143.Platinum hexafluoride, formation of,Plutonium, coulometric dtmn. of, 363.E.D.T.A. complexes of, 137.Plutonium(rrI), reduction to, 137.Plutonium-(In) and -(Iv), nitrates, ex-Plutonium(1v) isopropoxide, 137.Polarography, 364.Polonium, a+ phase transition in, 118.Polonium hydroxide, acidity of, 118.Polybutadiene, preparation of, 61.Polycladin, structure of, 252.Polycyclic compounds, 229.cycZoPolyenes, 234.Polyenoic acids in fish oils, 205.Polyethylene, high-melting, 55.Polyethylidene, structure of, 53.Polyhalide complexes, 120.Polymerisation, 53.142.tractability of, 137.monosulphide, preparation and pro-perties of, 118.structure of, 54.anionic, 59.by X - and y-ray irradiation, 68.cationic, 58.condensation, 58.free-radical, 54.stereospecific, 59.dielectric absorptions of, 89.irradiation of, 69.of, 57.189.Polymers, degradation of, 57.Poly (methyl methacrylate), y-irradiationPoly(methylsi1oxane) as reducing agent,Polymixin B,, amino-acids in, 347.Polynitro-aromatic compounds, titrationstructure of, 285.of, 364.Polypeptide antibiotics, biosynthesis of,Polystictin, structure of, 250.Polystyrene, y-irradiation of, 57.Potassium, dtmn.of, 362.indirect complexometric dtmn. of, 361.Praseodymium oxides, 130.Prednisone acetate, rearrangement of, 269.cycZoPropane, heat of hydrobrominationPropene, heat of hydrobromination of, 77.Propionamide, radical from, 11.Propionate radical, heat of formation of,72.Propionyl peroxide, heat of formation of,72.Propylene glycol, spectrophotometricdtmn. of, 377.Protactinium, 133.Proteins, purification of, 278.Pteridines, 249.Pyrethrosin, structure of, 219.Pyridine, compound of, with silicon tetra-Pyridines, 243.Pyridine alkaloids, 256.Pyridine l-oxides, oxide function in, 244.Pyridinium tetrabromo- and tetrachloro-Pyrimidine ring, biosynthesis of, 329.Pyrophosphorylases, 3 12.Pyrrole, nitration and thiocyanation of,241.Pyrrole trimer, structure of, 241.Pyrroles, 240.Pyrromycins, 230.Pyrylium salts, uses cf, in synthesis, 228.Punicic acid, structure of, 205.Purine ring, biosynthesis of, 332.347.of, 77.stereospecific polymerisation of, 61.structural investigation of, 279.chloride, 106.reactions of, 244.borate, 99.Qualitative analysis, 355.Quinolines and isoquinolines, 248.isoQuinoline alkaloids, 256.Quinones, 230.Quinonoid compounds, direct titration of,364.Radiation chemistry, 63.Radical reactions, 177.Radio-chemical analysis, 381.Radio-frequency spectroscopy, 7.Reactions in solution, 41.Reduction, methods of, 186.Relaxation times, 84.Restricted rotation, classical, 179.isoRetronecano1, structure of, 260.Rhenium(I), non-reduction of, 129.Rhenium carbonyls, 125.chloropentacarbonyl, 125.Rhenium(v) chloride, preparation of, 139.Rhenide ion, Re-, stability of, 138.Hexachlororhenate(Iv), potassium com-plex, 139426 INDEX OF SUBJECTS.Rhodium carbonyls, derivatives of, 126.Rhodium(Ir1) perchlorate, 140.Rhyncophylline, identity of, 258.D-Ribitol 5-phosphate, formation of, 301.a-D-Ribofuranose 1 : 5-diphosphate, syn-Ribmuclease (bovine), structure of, 280.Ribase &phosphate l-pyrophosphate, 332.(f)-Ricinoleic acid, synthesis of, 206.Ring systems, medium and large, con-Rotatory dispersion and configuration,Rotundifolone, structure of, 216.Rubidium, radio-chemical dtmn.of, 383.Ru scogenins, 2 7 2.Ruthenium carbonyl iodides, 125.nitrosyls, 139.tetroxide, reduction of, 139.thesis of, 301.formation of, 181.183.Samarium sulphide, constitution of, 130.a-Sanshool, structure of, and identity withneoherculin, 207.Sapogenins, steroidal, 272.rac.-Sarkomycin, 21 3.Sarpagine, structure of, 258.Sclerotiorin, structure of, 254.Scopoline, synthesis of, 254.Sea-water, dtmn. of gold in, 383.Sebacic acid, chromatographic separationSelenium, reduction of Se(1v) and Se(vr)Selenium dioxide, oxidation by, 191.of, 367, 368.to, 357.sulphate ion, 117.selenious acid, 117.Selenious acid, reaction of, with seleno-Selenosulphate ion, reaction of, withSesquiterpenes, 218.Seven-membered ring heterocyclic com-pounds, 251.Sialic acids, 320.enzymic release of, 327.preparation and sources of, 323.Silicon monoxide, non-existence of, 107.Silicon nitride, structure of, 107.Silicon tetrachloride, compound of, withpyridine, 106.Silane, difluoro-, dimensions of, 8.trimethylchloro-, pyrolysis of, 106.Silanes, aryloxy-, titrimetric dtmn.of,361.Silylphosphine, solvolysis of, 107.Silver, ferrometric dtmn. of, 359.polarimetric dtmn. of, 354.test for, and dtmn. of, 379.Silver acetate-iodine, oxidation by, 191.Silver thiocyanate, structure of, 145.Argentocyanide ion, structure of, 145.Small rings, alicyclic, 212.Sodium, indirect complexometric dtmn.Sodium benzoate, irradiation of, 70.Sodium borohydride, preparaiion andSodium hydroxide, hydrates of, 95.of, 361.uses of, 187.Sodium stannate trihydrate, structure of,Sodium tetramethoxyborate, 98.Sodium triethoxyalurninium hydride,Solasodine, 273.Solutions of organic compounds in strongSpectra, effect of conformation on, 184.Spectroscopy, absorption, 375.108.186.Nitrosylsodium, formation of, 110.acids, 150.electron resonance, 9.micro-wave, 7.nuclear magnetic resonance, 12.nuclear quadrupole resonance, 16.radio-frequency, 7.ultraviolet, 375.Spherophysine, structure of, 208.Spilanthol, identity of, with affinin, 207.PentacycZoSqualene, formation of, 224.As-Stenols, oxidation of, 263.Sterculic acid, structure of, 206.dihydro-, structure of, 206.Stereochemical effects on mesomerism,148.Stereochemistry, 170.Steric factors in cyclisation, 230.Steric hindrance to solvation, 185.Steroid alkaloids, 273.Steroid biogenesis, 275.Steroid 3-ltetones, reduction of, 264.Steroid sapogenins, 272.Steroids, 262.amino-, equatorial, deamination of, 263.A5-, 3/3-flUOrO-, preparation of, 262.general reactions of, 262.molecular rearrangement in, 267.oxo-, dihydroperoxides of, 264.total synthesis of, 274.Sterol side chain, degradation of, 269.trans-Silbene ozonide, heat of combustion,formation, and scission of, 72.Stipitatonic acid, occurrence of, 237.Streptomycin, biosynthesis of, 348.IStructural effects in nucleophilic substi-Subtilin, biosynthesis of, 345.Succinates, test for, and dtmn. of, 376.Sulphonation, 152.Sulphur, dtmn.of, in organic compounds,363.tution, 160.in petroleum products, 361.elementary, test for, 355.liquid, free radicals in, 11.plastic, constituents of, 115.Sulphur tetrafluoride, purification of, 11 7.Sulphur trioxide-water system, 116.Disulphur monoxide, 115.Fluorosulphates, stability of, 11 7.Peroxydisulphuryl difl.;oride, prepar-Persulphate, oxidation of sulphite by,ation of, 117.116.reaction of, with sulphite, 48.Sulphanes, H,S,, 11 7.with thiosulphate, 49INDEX OFSulphate, colorimetric-dtmn. of, 374.dtmn. of, by infrared spectroscopy,Sulphite, oxidation of, by persulphate,375.116.reaction of. with DersulDhate. 48.Sulphur acids, H&O, aAd His,+ 0,,116.117.Sulphuryl fluoride, dimensions of, 8.Thionyl bromide and chloride, dis-Thiosulphate, dtmn. of, 371.Tabernanthine, structure of, 259.Tantalum, separation of, 361.Tantalum pentachloride, physical con-sociation of, 11 7.from niobium, 355.stants of, 133.tetrabromide, preparation of, 133.Technetium(1v) chloride, formation of,139.Tellurium, absorptiometric dtmn. of, 372.Tenulin, 221.Terebic acid, preparation of, 212.Tetrachloroethylene, heat of chlorinationof, 77.Tetracyclines, biosynthesis of, 350.Tetraethylenepentamine, complex-form-ing tendency of, 124.Tetrafluoroethylene, heat of formation of,76.,B-Tetrahydrosantoninic acid, conform-ation of, 173.Tetramethyldiphosphine disulphide, struc-ture of, 111.Tetranitromethane, aqueous, effect ofy-rays upon, 68.Tetraphosphacyclobutane, tetralus(tri-fluoromethyl)-, 11 3.Tetronic acid, ethyl ester, synthesis of,200.Thallium(1) sulphide, oxidation of, 104.cycZoPentadienylthallium ( I ) , formationThermochemistry, 71.Thiazolines, 2-amino- and 2-mercapto-,2 : 2’-Thiazoloin, structure of, 242.,8-2-Thiazolyl-~-alanine, 242.Thioacetamide, hydrolysis of, 50.Thiocarbonyl chloride, structure of, 105.Thioctic acid, synthesis of, 243.Thiolacetic acid, heat of formation of,Thiolutin, biosynthesis of, 346.Thionaphthens, alkyl-, 246.Thiophens, 242.Thiophosphoryl bonds, dissociationThiourea, irradiation of, 70.Thorium, amperometric titration of, 365.Thorium iodides, 132.cycZopseudoTigogenin, oxidation of, 273.Tin, dtmn.of, in titanium alloys, 358.Tin, diethyl- and tri-ethyl-, salts of,of, 104.action of, with diphenylketen, 246.78.energies of, 79.dtmn. of, 372.jUB JECTS . 427Hexamethylditin, heat of reactionof, with bromine and with iodine,77.Organotin compounds, 193.Stannane, preparation of, 107.Stannane, triethyl-, formation of,Stannate, dtmn. of, as stabiliser inStannic chloride, reactions of, withSodium stannate trihydrate, structureTetramethyltin, heat of reaction withVinyltin compounds, 194.Titanium, basic acetate of, 131.sensitive test for, 372.separation of, 361.108.hydrogen peroxide, 364.alcohols, 107.of, 108.bromine, 77.Titanium ( 111) oxychloride, preparation of,131.Titanium(1v) oxysulphate, structure of,131.Dicyclopentadienyltitanium dichloride,reaction of, with triethylaluminium,102.Dititanoxanes, hexa-alkoxy-, 131.Toluene-3 : 4-dithiol, uses of, 370.Tomatidine, 273.Tomatine, 274.Trade effluents, dtmn.of volatile hydro-carbons in, 353.Transaminase, 3 17.Transition elements, 12 1.Trans-uranium elements, 136.Triazines, 245.Tribenzotropone, formation of, 237.Tricyclic compounds, 249.Trifluoroacetic acid as solvent, 105.Trifluoromethyl hypofluorite, decompos-Trimethylsilyl group, displacement of,Triphenyl phosphite, deoxygenation by,Triphenylmethyl cation, salts of, 106.Triphenylmethyls, substituted, stabilityTriphenylphosphine, deoxygenation ofTriterpenes, 221.Trithiocarbonate ion, hydrolysis of, 105.Tropane alkaloids, 254.Tropolones, 237.Tropones, 237.Tropylium (tropenium) salts, 236.Tungsten, dtmn. of trace impurities in,complexes of, 122.ition of, 119.154.189.of, 165.peroxides by, 189.naturally occurring, 224.383.oxides of, 135.Heteropolytungstates, 135.Tylophorine, structure of, 262.Tyrocidin A and B, amino-acids in,Tyrosine, X-ray irradiation of, 70.347428 INDEX OF SUBJECTS.Ulein, structure of, 259.Uranium, colorimetric dtmn. of, 373.Uranium(v~), spectrophotometric dtmn,Uranium alkoxides, 136.dtmn. of, in alloys, 359.of, 375.hydride, 135.polyselenide, 136.Valeric acid, y- and &amino-, synthesis of,Valeroidine, configuration of, 254.Vanadium, colorimetric dtmn. of, 370.Vanadium(v), colorimetric dtmn. of, 370.Vanadium pentafluoride, preparation of,Vanadium(v) ternary arsenides and phos-Variamine-blue as redox indicator, 359,Vinyl bromide, co-poiymerisations of,Vinyl compounds of metals and metalloids,Violacein, structure of, 248.Vitamin A, 200.Vitamins D, 270.Vitexin, structure of, 252.Voacangine, structure of, 259.277.spot test for, 381.dtmn. of, 358.132.phides, 133.tetrachloride, reactions of, 133.369.56.194.Volumetric analysis, 358.Vomalidine, structure of, 258.standards for, 358.Water, dielectric relaxation process in, 87.Wedelolactone, structure of, 254.Willagenin, structure of, 272.Xanthatin, structure of, 219.Xanthinin, structure of, 219.Xanthoperol, structure of, 222.Xylobiose, alkaline degradation of, 298.D-Xylose 3-phosphate, preparation of, 302.Xylotriose, alkaline degradation of, 398.9-Xylylene, formation of, 228.Ytterbium, dissolution of, in ammonia,dtmn. of, 39.131.Zeaxanthin, preparation of, 201.Zeorin, structure of, 225.Zinc, dimethyl-, bond dissociation energiesin, 81.radicals from, 11.Zinc, potentiometric dtmn. of, 362.spectrophotometric dtmn. of, 372.Zinc sulphide, m. p. of, 145.Zirconium, colorimetric dtmn. of, 371.Zirconium tetrachloride, properties of, 132.trichloride, thermal decomposition of,132

ISSN:0365-6217    

DOI:10.1039/AR9575400417

出版商:RSC    

年代:1957

数据来源: RSC

摘要:

PRINCIPAL REFERENCES USED IN CHEMICAL SOCIETYPUBLICATIONS AS FROM JANUARY, 1958.REFERENCE.Acta Acad. Aboensis, Math.Phys. .Acta Biol. Acad. Sci. Hung. .Acta Brev. Neevland. Physiol.Pharnaacol. Microbiol. .Acta Chem. Fennica .Acta Chem. Scand. .Acta Chim. Acad. Sci. Hung.Acta Chinz. Sinica .Acta Cryst. .A cta Metallurgica .Acta Pathol. Microbiol. Scaizd.Acta Phys. Acad. Sci. Hung.Acta Phys. et Chem. Szeged. .Acta Physicochim. U.R.S.S.Acta Physiol. Acad. Sci. Hung.Acta PhysioZ. Phavmacol.Neerland. .Acta Phytochim. (Japan) .Acta Vifaminol.Adv. Agron.Adu. Biol. Med. PhysiEs .'Adv. Carbohydrate Chern. .Adv. Catalysis .Adv. Chem. Erg. .Adv. Colloid Sci.Adv. ElectronicsAdv. Enzymol. .Adv. Food Res. .A dv. Phys.Adv. Protein Chem..Advancement Sci. .Ajinidad .Agra Univ. .J. Res. (Sci.)Agric. Chem. ,Agrokdm. &s Talajtan .Ambix ..Amer. Ceram. Soc. Bulletirt .Amer. Chem. J . .Amer. Dyestuff Reporter .Amer. Gas J . .Amer. Inst. ChewEngineers J .Amer. J . Bot. .Amer. J . Pharm. .Amer. J . Physiol. .Amer. J . Sci. .Atner. Perfumer Aromutics .Amer. Perfunier Essent. OilRev. .Anais Acad. brasil. Cienc. .FULL TITLE.Acta Academiae Aboensis, Rfathematica et Physica.Acta Biologica Academiae Scientiarum Hungaricae.Acta Brevia Neerlandica de Physidogia, Pharmacologia,Microbiologia e.a. (name changed with vol. 17, 1950, toActa Physiologica et Pharmacologica Neerlandica) .Acta Chemica Fennica (formerly second name for SuomenKemistilehti ; dropped with vol.8, 1935).Acta Chemica Scandinavica.Acta Chimica Academiae Scientiarum Hungaricae.Acta Chimica Sinica.Acta Crystallographica..4cta Metallurgica.Acta Pathologica et hiicrobiologica Scandinavica.Acta Physica Academiae Scientiarum Hungaricae.-4cta Physica et Chemica. Acta Universitatis Szeged-iensis.Acta Physicochimica U.R.S.S. (ceased publication withvol. 22, 1947).Acta Physiologica Academiae Scientiarum Hungari-cae ..Acts Physiologica et Pharmacologica Neerlandica(formerly Acta Brevia Neerlandica de Physiologia,Pharmacologia, Microbiologia, e.a.) .Acta Phytochimica (Tokyo).Acta Vitamhologica.Advances in Agronomy.Advances in Biological and Medical Physics.Advances in Carbohydrate Chemistry.Advances in Catalysis.Advances in Chemical Engineering.Advances in Colloid Science.Advances in Electronics.Advances in Enzymology.Advances in Food Research.Advances in Physics.Advances in Protein Chemistry.Advancement of Science.Afinidad.Agra University Journal of Research (Science).Agricultural Chemicals.AgrokCmia 4s Talajtan.Ambix.Journal of the Society for the Study ofAlchemy and Early Chemistry.American Ceramic Society Bulletin.American Chemical Journal.American Dyestuff Reporter.American Gas Journal.American Institute of Chemical Engineers Journal.American Journal of Botany.American Journal of Pharmacy.American Journal of Physiology.American Journal of Science.American Perfumer and Aromatics.American Perfumer and Essential Oil Review (namechanged with vol.66, 1966, to American Perfumer andAromatics).Anais da Academia brasileira de Ciencias.42 430 PRINCIPAL REFERENCES USED.REFERENCE.Anais Assoc. brasil. Quim. .Anais Assoc. quisn. Brasil .Anales Asoc. qudm. argentinaAnales Bromatol.Anales Fac. Farm. Bioquim.,Univ. nac. mayor SanMarcos .A nales real SOC. rspafi. Fis.Quim. .Analyst .Analyt. Chew. .Analvt. Chiin. Acta .Anat. Record .Angew. Chem. .Annalen .Ann. Acad. Sci. kennicae .‘Ann. Biochem. Exp. Med.(India) .Ann. Bot. .Ann. Chim. (France) .Ann. Chain. (Italy) .Ann. Chim. anal. et Chim.appl. .Ann. Chinz. appl. .Ann. Chim. Phys. .Ann. Endocrinol. .Ann. Fals. Fraudcs .Ann. Ferment. .Ann. Inst. Pasteur .Ann.New York Acad. Sci. .Ann. Nutrition Aliment. .Ann. pharm. belges .Ann. pharm. frang. .Ann. Physique .Ann. Physik .Ann. Report Fac. Pharm.,Ann. Report ITSUU Lab.A n w Report Takamine Lab..Ann. Reports .Ann. Reports SOC. Chem. Ind.Kanazawa Univ.Ann. Rev. Biochenz. .Ann. Rev. Microbiol. .Ann. Rev. Nuclear Sci. .Amn. Rev. Petroleum Technol.Ann. Rev. Phys. Chem. .Ann. Rev. Plant Physiol. .Ann. Sci. .Amn. SOC. sci. Bruxelles .Ann. Sper. agrar. .Ann. Umiv. M . Curie-Sklodowska .FULL TITLE.Anais da AssociaCiio brasiIeira de Quimica.Anais da Associaciio quimica do Brasil (name changedwith vol. 11, 1952, to Anais da Associa@o brasileira deQuimica).Anales de la Asociacibn quimica argentina.Anales de Bromatologica.Anales de la Facultad de Farmacia y Bioquimica,Universidad nacional mayor de San Marcos (re-commenced publication in 1950 with vol.1).Anales de la real Sociedad espaiiola de Fisica y Quimica.Analyst.Analytical Chemistry.Analytica Chimica Acta.Anatomical Record.Angewandte Chemie (the name Die Chemie was used forAnnalen der Chemie (Liebig’s).Annales Academiae Scientiarum Fennicae (SuomalaisenAnnals of Biochemistry and Experimental MedicineAnnals of Botany.Annales de Chimie.Annali di Chimica.Annales de Chimie analytique et de Chimie appliqude(name changed with vol. 24,1942, to Annales de Chimieanalytique, and then with vol. 29, 1947, to Chimieanalytique) .Annali di Chimica applicata (several changes, the lastwith vol. 40, 1950, to Annali di Chimica).Annales de Chimie et de Physique [divided in 1914 intotwo journals : Annales de Chimie (Paris) and Annalesde Physique].Annales d’Endocrinologie.Annales des Falsifications et des Fraudes.Annales des Fermentations (discontinued with vol. 8,Annales de 1’Institut Pasteur.Annals of the New York Academy of Sciences.Annales de la Nutrition et de l’hlimentation.Annales pharmaceutiques belges.Annales pharmaceutiques fraqaises.Annales de Physique.Annalen der Physik.Annual Report of the Faculty of Pharmacy, KanazawaAnnual Report of ITSUU Laboratory.Annual Report of the Takamine Laboratory.Annual Reports on the Progress of ChemistryAnnual Reports of the Society of Chemical Industry onthe Progress of Applied Chemistry (changed with vol.34, 1949, to Reports on the Progress of AppliedChemistry),VOI.55, 1942, to V O ~ . 58, 194.5).Tiedeakatemian Toimituksia) .(India).1943).University.Annual Review of Biochemistry.Annual Review of Microbiology.Annual Review of Nuclear Science.Annual Reviews of Petroleum Technology.Annual Review of Physical Chemistry.Annual Review of Plant Physiology.Annals of Science.Annales de la Soci6t6 scientifique de Bruxelles.Annali della Sperimentazione agraria (not publishedAnnales Universitatis Mariae Curie-Skfodowska (severalbetween vol. 40, 1941, and vol. 1, 1947).sections)PRINCIPAL REFERENCES USED. 43 1REFERENCE.Annuaire Acad. voy. Belg. .Antibiotics and ChemotherapyAppl. S$ectroscopy .Arch. Biochenz..FULL TITLE.Annuaire Acad6mie royale dc Belgique.Antibiotics and Chemotherapy.Applied Spectroscopy.Archives of Biochemistry (name changed with vol.31, 1951, to Archives of Biochemistry and Bio-physics).Archives of Biochemistry and Biophysics.Archiv fur experimentelle Pathologie und Pharmako-logie (Naunyn-Schmiedeberg's) .Archiv fur hlikrobiologie.Archiv der Pharmazic.Archives des Sciences.Archivio di Scienze biologiche.Arhiv za Kemiju (name changed with vol. 28, 1956, toArkiv for Fysik.Arkiv for Geofysik.Arkiv for Kemi.Arkiv for Kemi, Mineralogi och Geologi (divided in 1940into Arkiv for Kemi and Arkiv for Mineralogi ochGeologi) .American Society for Testing Materials Bulletin.Atomics.Atti della Accademia nazionale dei Lincei, Rendicontidella Classe di Scienze fisiche, matematiche e naturali.Atti della [reale] Accademia della Scienze di Torino.Classe di Scienze fisiche, matematiche e naturalj.Australian Journal of Agricultural Research.Australian Journal of Applied Science.Australian Journal of Biological Sciences.Australian Journal of Chemistry.Australian Journal of Experimental Biology and MedicalAustralian Journal of Physics.Australian Journal of Science.Avhandlinger utgitt av det norske Videnskaps-Croatica Chemica Acta).Science.Akademi i Oslo.Arch.Biochem. Rioflhys. .Arch. exp. Pathol. Pharmakol.Arch. Mikrobiol.Arch. Pharnz. .Arch. Sci. .Arch. Sci. biol. (Italy) .Arhiv Kem. .Arkiv Fys.Arkiv Geofys. .Arkiv Keini .Arkiv Kemi, M'ineralog.Geol.A S T M Bull. .Atomics .Atti Accad. 9za.z. Lincei, Rend.Classe Sci. fis. mat. nat. .Atti Accad. Sci. Torino, ClasseSci.$s. mat. nat. .Austral. J . Agric. Res. .Austral. J . Appl. Sci. .Austral. J . Biol. Sci. .Austral. J . Chew. .Austral. J . Exp. Biol. Med.Austral. J . Phys. .Austral. J . Sci. .Avh. norske Videnskaps-A kad.Oslo . . .s c i . .Battelle Tech. Rev. .Ber.Ber. deut. bot. Ges. .Der. Ohara Inst. landwirfsclz.Biol., Okayama Univ. .Ber. ukrain. biochcm. Inst. .Bcrg- u. huttennzann. Monatsh.montan. Hochschztle LeobenBiochem. J . .Biochenz. SOC. S-ymp. .Biochem. (U.S.S.R.) .Biochenz. Z. .Biochim Bioph.ys. Acta .Biojizika .Biokhinziya . .Biol. Rev. Camb. Phil. SOC. .1301.Inst. Quini. agric. (Brazil)Bol. Itzst. Quiitt. Univ. nac.Bol. Sac. chilena Qtdnt. .Rol. Sac. quint. Peru .azitoii. iile'xico .Battelle Technical Review.Berichte der deutschen chemischen Gesellschaft (dis-continued with vol. 77, 1944; continued as ChemischeBerichte with vol. 80, 1947).Berichte der deutschen botanischcn Gesellschaft.Berichte des Ohara Instituts fur landwirtscliaftlicheBiologic, Oltayama Universitat.Berichte des ukrainischen biochemischen Instituts (namechanged with vol. 7 ; now Ukrainslrii biolthimicheskiiZhurnal) .Berg- und huttenmannische Rionatshefte der montan-istichen Hochschule in Leoben.niocliemical Journal.Biochemical Society Symposia.Biochemistry (U.S.S.R.). New York. U.S. translationRiochemische Zeitschrift.Riochimica et Biophysica Acta.Riofizika.Biokhimiya.[See also Biochemistry (U.S.S.R.)].Biological Reviews of the Cambridge PhilosophicalBoletim do Instituto de Quimica agricola, MinistCrio daI3oletin del Instituto de Quimica de la UniversidadBoletin de la Sociedad chilena de Quimica.Roletin de la Sociedad quimica del Peru.of Riokhimiya. Different pagination.Society.Agricultura (Brazil).nacional autonoma de Rlkxico432 PRINCIPAL REFERENCES USED.REFERENCE.Boll. chim. farm. .Boll. sci. Fac. Chim. ind.Boll. SOC. ilal. Biol. sper. .Botyu-Kagaku .Brcnnstofl-Chem. .Brit. Bull. Spectroscopy .Brit. Chew Eng. .Brit. Chemist .Brit. J . Appl. PJiys. .Brit. J . Pharmacol. .Brit. J . Phot. .Brit. Med. Bull.Brit.Med. J . .Brit. Overseas Pharm. .Bul. Chim. SOC. Cltim.Rorndnia .BolognaBul. Inst. folitech. la+ .Bull. Acad. polon. Sci.. .Bull. Acad. Sci. U.R.S.S. .Bull. Acad. Sci. U.S.S.R. .Bull. Agric. Chenz. SOC. JapanBull. Anzer. Ceram. Soc. .Bull. Amer. Phys. Soc. ,Bull. Brit. Coal UtilisationBull. Brit. SOC. History Sci. .Bull. Brit. SOC. RheoE. .Bull. Calcutta School Tvop.Bull. Central Electrochem. Res .Bull. Central Res. Inst., Univ.Bull. Chem. SOC. Japan .Bull. Classe Sci., Acad. roy.Bull. Imp. Inst. .Res. Assoc. .Med. . .Inst., Karaikudi .Travancore .Belg. .Bull. India Sect. Electrochem.Bull. Inst. Chein. Res., KyotoBull. Inst. Metal Finishing .Bull. Inst. Mining Met. .Bull. Inst. Nuclear Sci. BorisSOC..Univ. .Kidrich . .Bull. Inst. Paper Chew. .Bull. Inst. Phys. Chcm. Res.Bull. Johns Hopkins Hosp. .Bull. Kobayasi Inst. Phys. RCS.Bull. Narcotics .Tokyo .FULL TITLE.Bolletino chimico farmaceutico (irregular between 1942Bollettino scientific0 della FacoltA di Chimica industrialeBollettino della SocietA italiana di Biologia sperimcn-Botyu-Kagaku. (Scientific Insect Control.)Brennstoff-Chemie (not published, as such, between vol.24, 1943, and vol. 30, 1949).British Bulletin of Spectroscopy.British Chemical Engineering.British Chemist.British Journal of Applied Physics.British Journal of Pharmacology and Chemotherapy.British Journal of Photography.British Medical Bulletin.British Medical Journal.British and Overseas Pharmacist.Buletinul de Chimie purti gi aplicata, Societatea deChimie din RomAnia (name changed in 1939 fromBuletinul de Chimie pur5 si aplicata a1 SocietiitiiR o d n e de Chimie).and 1946).di Bologna.tale.Buletinul Institutului Politechnic din Ta$.Bulletin de 1’Acaddmie polonaise des Sciences.Bulletin de I’Acaddmie des Sciences de l’U.R.S.S.(subtitle used formerly for Izvestiya Akademii NaukS.S.S.R.).Bulletin of the Academy of Sciences of the U.S.S.R.New York. (US.translation of Izvestiya AkademiiNauk S.S.S.R., Otdelenie khimicheskikh Nauk.Different pagination. )Bulletin of the Agricultural Chemical Society of Japan.Bulletin of the American Ceramic Society.Bulletin of the American Physical Society.Bulletin of the British Coal Utilisation ResearchBulletin of the British Society for the History of Science.Bulletin of the British Society of Rheology.Bulletin of the Calcutta School of Tropical Medicine.Association.Bulletin of the Central Electrochemical ResearchInstitute, Karaikudi.Bulletin of the Central Research Institute, University ofTravancore (3 series).Bulletin of the Chemical Society of Japan.Bulletin de la Chsse des Sciences, AcadCmie royale deBelgique.Bulletin of the Imperial Institute, London (replaced in1949 by 2 journals : Colonial Plant and Animal Pro-ducts, and Colonial Geology and Mineral Resources).Bulletin of the India Section, the ElectrochemicalSociety.Bulletin of the Institute for Chemical Research, KyotoUniversity.Bulletin of the Institute of Metal Finishing.Bulletin of the Institution of Mining and Metallurgy.Bulletin of the Institute of Nuclear Sciences ‘‘ BorisKidrich.” Formerly Recueil des Travaux de 1’Institutdes Recherches sur la Structure de la Matikre, Belgrade.Bulletin of the Institute of Paper Chemistry.Bulletin of the Institute of Physical and ChemicalResearch, Tokyo [name changed with vol.24,1949, toReports of the Scientific Research Institute (Japan)].Bulletin of the Johns Hopkins Hospital.Bulletin of the Kobayasi Institute of Physical Research.Bulletin on NarcoticsPRINCIPAL REFERENCES USED. 433REFERENCE. FULL TITLE.Bull. Res. Council Israel .Bull. sci. Conseil Acad.R.P.F., Yougoslauie. .Bull. SOC. chim. belges .Bull. SOC. chim. Beograd .Bull.SOC. Chim. biol. .Bull. Soc. chim. France .Bull. Soc. roy. Sci. Lit?ge. .Bull. Soc. sci. Rretagne .C.S.I.R. Res. Rev. (S. Africa)Cahiers Phys. .Canad. Chena. Process I n d . .Canad. Chem. Processing .Canad. J . Biocherx Physiol.Canad. 1. Bot. .Canad. 7. Chein.Canad. J . Chem. EngCanad. J . Med. Sci.Canad. J . Phys.Canad. J . Res. .Canad. J . Technol.Canad. J . 2001. .Cellulosechemie .Cereal Chem. .Cesk. Biol.Cesk. Farm. .Chem. Abs.Chem. Age .Chern. Analit. .Chem. and I n d . .Chem. Process ERg.Chenz. Ber.Chem. Eng. .Chem. Eng. (Japan)Chel-n. Eng, NewsChem. En;. Progr.Chem. Eng. Pmgr., Mono-Chem. Eng. Progr., Symp. .Chena. Eng. Sci. .Chem. Erde .Chem. Fabrik .Chena. High Polymew (Japan)Chem.in CanadaChem. I n d . (Diisseldouj)Chem. Ind. (U.S.S.R.) .graph .Chem.-Ing.-Tech. .Chem. Listy .Chem. Obzor .Chem. Process Eng. .Chem. Products .Chem. pruinysl .Bulletin of the Research Council of Israel.Bulletin scientifique, Conseil des Acad6mies de la R.P.F.,Bulletin des SocidtCs chimiques belges.Bulletin de la SocidtC chimique de Beograd.Bulletin de la SociCtC de Chimie biologique.Bulletin de la SociCtC chimique de France.Bulletin de la SociCt6 royale des Sciences de Liege.Bulletin de la Soci6tC scientifique de Bretagne.C.S.I.R. Research Review (South Africa).Cahiers de Physique.Canadian Chemistry and Process Industries (namechanged with vol. 35, 1951, to Canadian ChemicalProcessing).Canadian Chemical Processing.Canadian Journal of Biochemistry and Physiology.Canadian Journal of Botany.Canadian Journal of Chemistry.Canadian Journal of Chemical Engineering.Canadian Journal of RIedical Science.Canadian Journal of Physics.Canadian Journal of Research (replaced in 1950 byCanadian Journal of Botany, Canadian Journal ofChemistry, etc.).Canadian Journal of Technology (name changed withvol.35, 1957, to Canadian Journal of ChemicalEngineering).Canadian Journal of Zoology.Cellubsechemie (irregular issue, now discontinued).Cereal Chemistry.Ceskoslovenskzi Riologie.Ceskoslovensk6 Farmacie.Chalmers Tekniska Hogskolas Hsntllingar.Chalmers Univ. Technol. Gothenburg.)Chemical Abstracts.Chemical Age.Chemia Analityczna.Chemistry and Industry.Chemical and Process Engineering.Chemische Berichte.Chemical Engineering.Chemical Engineering.Japan.Chemical and Engineering News.Chemical Engineering Progress.Chemical Engineering Progress, Monographs.Chemical Engineering Progress, Symposia.Chemical Engineering Science.Chemie der Erde.Chemische Fabrik (name changed with vol. 15, 1942,Chemistry of High Polymers (Japan).Chemistry in Canada.Chemische Industrie.Chemical Industry (U.S.S.R.). New York. (U.S.translation of Khimicheskaya Promyshlennost’.Different pagination.)Chemie-Ingenieur-Technik (formerly AngewandteChemie, section B).Chemickk Listy.Chemicky Obzor.Chemical and Process Engineering.Chemical Products and the Chemical News.Chemicky prumysl.You go slavie .(See Trans.to Chemische Technik)434 PRINCIPAL REFERENCES USED.REFERENCE.Chem.Rev..Chenn. SOC. Special Publ. .Chem. Tech. (Berlin) .Chem. Tech. (Dordrecht) .Chem. Trade J . .Chem. WeekbladChem. Zentr . ,Chevn.-Ztg. .Chem. Zvcsti .Cltenzia .Chemist-Analyst .Chemist and Druggist .Chemistry. (Quart. ChineseChern. SOC., Formosa) .C h i m analyt. .Chirizia (Switz.) .Chimica c Industria .Chiinie ei Industrie .Chinese J . Phys.. .Ci5ncia .Cllnicn Chirn. Acta .C1ini;al Chcnz. .Coll. Czech. Chein. Cornnt. .Colloid J . (U.S.S.R.) .Colonial Geol. Mineral Re-Colonial Plan; A nivnaiCornbztstion a?td Flame .sources .Pvoducts .Conzm. Fac. Sci. Univ.Cornpl. vend. .Conzpt. reitd. Acad. Sci.U.H.S.S. .Ankava .Cofnpt.rend. SOC. Biol. .Compt. vend. Trav. Lab. Carls-bevg .Concrete Quavt. .Contvib. Boyce ThompsonInst. .Contrib, Cientific., Univ.Batenos Aires, Ser. C,Qzkirn. .Corrosion .Cvoat. Chem. Acta .Crookes’ Digest .Current Sci. .Dansk Tidsskr. Farm.Declaetza Monograph. .Deut. Apoth.-Ztg. .Deut. Lebensm.-Rundschau .Die Cheinie .Discuss. Faraday Soc. .Diss. Abs. .FULL TITLE.Chemical Reviews.Chemical Society Special Publication.Chemische Technik.Chemische Techniek (Dordrecht) [name changed in 1916to Chemische en Pharmaceutische Techniek (Dord-recht)].Chemical Trade Journal.Chemisch Weekblad.Chemisches Zentralblatt.Chemiker-Zeitung.Chemick6 Zvesti, SlovenskA Academia Vied, Brati-slava.Chemia.Chemist-Ana 1 yst.Chemist and Druggist.Chemistry.cal Society, Formosa.Chimie analytique.Cliimia.(Switzerland.)Chimica e l’tndustria. Milan.Chimie et Tndustrie.Chinese Journal of Physics.Ciencia.Clinica Chimica Acta.CI iiiical Chemistry.Collection of Czechoslovak Chemical CommunicationsColloid Journal (U.S.S.R.). New York. (U.S. trans-Different pagination.)Colonial Geology and Mineral Resources.Colonial Plant and Animal Products.Combustion and Flame. (Quarterly Journal of theCombustion Institute.)Communications de la FacultC des Sciences de 1’Uni-versitB d’Ankara.Comptcs rendus hebdomadaires des S6ances deI’AcadCmie des Sciences.Comptes rendus de 1’AcadCmie des Sciences de l’U.R.S.S(subtitle used until vol.56, 1947, for DokladyAkademii Nauk S.S.S.R.).Comptes rendus des S6ances de la SociCtC de Biologie etdes Filiales.Comptes rendus des Travaux du Laboratoire deCarlsberg.Concrete Quarterly.Contributions from the Boyce Thompson Institute.Contributiones Cientificas, Universidad de Buenos Aires,Serie C, Quimica.Corrosion.Croatica Chemica Acta.Crookes’ Digest.Current Science.Published quarterly by the Chinese Chemi-(not published between 1940 and 1946).lation of Kolloidnyi Zhurnal.(Formerly Arhivza Kemiju.)Dansk Tidsskrift for Farmaci.Dechema Monographien.Deutsche Apothelcer-Zeitung.Deu tsch e Lebensmittel-Ru ndschau.Die Chemie (name used from vol. 65, 1942, to vol. 58,Discussions of the Faraday Society.Dissertation Abstracts.Ann Arbor, Mich. (Abstracts1‘315, in place of Angewandte Chemie).of some U.S. theses, issued commercially.PRINCIPAL I'cEFERENCES USED. 435REFERENCE.Doklady Akad. Nauk S.S.S.R.D.S.I.R. Publ. .DyestufisEcon. Proc. Roy. Dublin Soc.Elektrotech. 2. .EndeavourEngenharia e Qulmica .EnzynzoEogia -Erdd u. Kohle .Ergebn. Enzyniforsch. .Ergebn. cxakf. Naturwiss. .Ergebn. Vitamin- u. Hornion-Euclides .Expericntia ,Fed. Proc.Fefte u. Seifeia .Finska Kemistsam jundetsFiz. Metall. i Metallov. .Fluid Handling .Food .Food Eng.Food Manuf. .Food Rcs. .Food Technol. .Food Technol. Austral.Forschungsber. Wirtschajts-u. VcrkehrsministeraumsNovdrhein- WcstfalenFortschr. chem. Forsch. .Forfschr. Ghem. org. Natitr-stojfe .Fuel .jovsch..Medd. .Gaxzetta .GCnic chim.Geochemistry (U.S.S.R.) .Geochim. Cosmochim. Acta .Geokhimiya .Gidvokhirn. Mat.Giorn. Biochim. .Giorn. Ghim. appl. .Giorn. Chinz. ind. .Giorn. Chiin. ind. appl, .Gvasas y A ceitesHelv. Chinz. Acta .Helv. Phys. Acta .Helv. Physiol. Pharvnacol. A ctaHoudry Pioneer .I n d . Chemist .I n d . chim. . .I n d . chim. belge .FULL TITLE.Doklady Akademii Nauk S.S.S.R.D. S.I. R. Publication.Dyestuffs.[See also Yroseedi(National Aniline Division, Allied Chemicalings of the Academy of Sciences of the U.S.S.R.]and Dyes Corp., New York.)Economic Proceedings of the Royal Dublin Society.Elektrotechnische Zeitschrift.Endeavour.Engenharia e Quimica.Enzymologia.Erdol und Kohle.Ergebnisse der Enzymforschung.Ergebnisse der exakten NaturwissenschaftenErgebnisse der Vitamin- und Hormoniorschung (dis-continued after vol.2, 1939)Euclides.Experientia.Federation Proceedings.Fette und Seifen einschliesslich der AnstrichmittelFinska Kemistsamfundets Meddelanden (Suomen Icemi-Fizika Metallov i Metallovdenie.Fluid Handling.Food.Food Engineering.Food Manufacture.Food Research.Food Technology.Food Technology in Australia.Forschungsberichte des Wirtschafts- und Verkehrs-stiseuran Tiedonantoja).ministeriums Nordrhein-Westfalen.Fortschritte der chemischen Forschung.Fortschritte der Chemie organischer Naturstoffe.Fuel. (Quarterly Journal of Fuel Science.)Gazzetta chimica Italiana.GCnie chimique (suppl.to Chimie et lndustrie).Geochemistry (U.S.S.R.). New York. (U.S. transla-tion of Geokhimiya. Different pagination.)Geochimics et Cosmochimica Acta.Geokhimiya. [See also Geochemistry (U.S.S.R.).]Gidrokhimicheskie Materialy.Giornale di Biochimica.Giornale di Chimica applicata (name changed in 1930Giornale di Chimica industriale (name changed in 1920Giornale di Chimica industriale ed applicata (nameGlasnik Khemiskog Drushtra Beograd. (See BulletinGrasas y Aceites.Helvetica Chimica Acta.Helvetica Physica Acta.Helvetica Physiologica et Pharniacologica Acta.Houdry Pioneer.to Giornale di Chimica industriale ed applicata).to Giornale di Chimica industride ed applicata).changed in 1936 to La Chimica e 1'Industria).de la SociCt6 chimique de Beograd.)(Houdry Process Corp., Philadelphia.)Industrial Chemist.L'Industrie chimique et le Phosphate reunis.Industrie chimique belge436 PRINCIPAL REFERENCES USED.REFERENCE.Ind. Eng.Chem.Ind. Eng. Chem. Anal. .Ind. Eng. Chem., Chem. Eng.Data Ser. .I n d . Finishing .Ind. Parfumerie . .India Rubber J . .Indian J . Pharm. .Indian J . Phys. .Indian Pharmacist .Industria y Quimica .Ingbnietcr cham. .Inorg. Synth. .Inst. Hierro Acevo .Inst. int. Chim. Solvay,Conseal Chim.Inst. Petroleum Rev. .Instr. News .I n t . Z. Vitaminforsch. .Interchem. Rev. .Infernat. J . Appl. RadiationIsotopes .Iodine Inf. .Iowa State Coll. J . Sci. .IsotopicsIzvest. Akah. NaiJk S.S.S.R.;Otdel. khim. Nauk .Izvest.Sekt. Platiny drug.blagorod. Metal., Inst.obschchei neorg. Khim. .Izvest. Sekt. jz.-khim. Anal.Inst. obshchei neorg. Khim.J . . . . .J . Agric. Chem. Soc. Japan .J . Agric. Food Chem. .J . Agric. Rcs. .J . Agric. Sci. .J . Amer. Assoc. CerealChemists .J . Amer. Ceram. SOC. .J . Amer. Chem. Soc. .J . Amcr. Leather Chemists’J . Amer. Oil Chemists’ SOC. .J . Amer. Pharm. Assoc. .Assoc. .J . Analyt. Chem. (U.S.S.R.)J . Andhva Univ. Chem. SOC.J . Appl. Chem. .J . Appl. Chem. (U.S.S.R.)J . Assoc. OBc. Agric.Chemists .FULL TITLE.Industrial and Engineering Chemistry (name changedwith vol. 15, 1923, from Journal of Industrial andEngineering Chemistry).Industrial and Engineering Chemistry, Analytical Edi-tion (name changed in 1947 to Analytical Chemistry).Industrial and Engineering Chemistry, Chemical andEngineering Data Series.Industrial Finishing.Industrie de la Parfumerie.India Rubber Journal.Indian Journal of Pharmacy.Indian Journal of Physics.Indian Pharmacist.Industria y Quimica.IngCnieur chimiste (not published mid-1943 to mid-Inorganic Syntheses.Instituto de Hierro y del Acero.Institut international de Chimie Solvay, Conseil deInstitute of Petroleum Review.Instrument News.(Perkin-Elmer Corp., Norwalk, Conn.)Internationale Zeitschrift fur Vitaminforschung.Interchemical Review.International Journal of Applied Radiation and Iso-topes.Iodine Information.Iowa State College Journal of Science.Isotopics.Izvestiya Akadernii Nauk S.S.S.R., Otdelenie khimi-cheskikh Nauk.Moscow. (See also Bulletin of theAcademy of Sciences of the U.S.S.R.).Izvestiya Sektora Platiny i drugikh blagorodnykhMetallov, Institut obshchei i neorganicheskoi Khimii,Akademii Nauk S.S.S.R.Izvestiya Sektora fizilto-khimicheskogo Analiza, Institutobshchei i neorganicheskoi Khimii, Akademii NaukS.S.S.R. (formerly lzvestiya Instituta fiziko-lthimi-cheskogo Analiza) .1945).Chjmie.Journal of the Chemical Society.Journal of the Agricultural Chemical Society of Japan.Journal of Agricultural and Food Chemistry.Journal of Agricultural Research (discontinued with volJournal of Agricultural Science.Journal of the American Association of Cereal Chemists(name changed with vol. 8, 1923, to Cereal Chemistry).Journal of the American Ceramic Society.Journal of the American Chemical Society.Journal of the American Leather Chemists’ Association.Journal of the American Oil Chemists’ Society.Journal of the American Pharmaceutical Association(two editions : Scientific Edition and PracticalPharmacy Edition).Journal of Analytical Chemistry (U.S.S.R.).New York.(U. S . translation of Zhurnal analiticheskoi Khimii.Different pagination.)Journal of the Andhra University Chemical Society.Journal of Applied Chemistry.Journal of Applied Chemistry (U.S.S.R.). New York.(U.S. translation of Zhurnal prikladnoi Khimii. DifferentJournal of the Association of Official Agricultural78, 1949).pagination.)ChemistsPRINCIPAL REJTERENCES USED. 487REFERENCE.FULL TITLE.Journal of Biochemistry. Japan.Journal of Biological Chemistry.Journal of Biological Sciences.Journal of Chemical Education.Journal of the Chemical, Metallurgical and MiningSociety of South Africa (name changed with vol. 57,1956, to Journal of the South African Institute ofMining and Metallurgy.)Journal of Chemical Physics.Journal of the Chemical Society.Journal of the Chemical Society of Japan.Journal of the Chemical Society of Japan, IndustrialJournal de Chimie physique.Journal of the Chinese Chemical Society (New Series-Journal of Chromatography.Journal of Colloid Science.Journal of the Council for Scientific and IndustrialResearch, Australia (replaced, after vol. 21, 1948, byAustralian Journal of Agricultural Research, andAustralian Journal of Applied Science).Chemistry Section.Formosa).Journal of Economic Entomology.Journal of the Electrochemical Society.Journal of the Electrochemical Society of Japan (betweenJournal of the Faculty of Science, Hokkaido Imperial'Journal of the Faculty of Science, (Imperial) University,Journal of the Fisheries Research Board of Canada.Journal of the Franklin Institute.Journal of General Chemistry (U.S.S.R.).Journal of General Physiology.Journal of Geology.Journal of Histochemistry and Cytochemistry.Journal of the Imperial College Engineering Society.Journal of Industrial and Engineering Chemistry (namechanged with vol.15, 1923, to Industrial andEngineering Chemistry).Journal of the Indian Chemical Society.Journal of the Indian Chemical Society (Industrial andNews Edition).Journal of the Indian Institute of Science.Journal of Inorganic Chemistry (U.S.S.R.).New York.(US. translation of Zhurnal neorganicheskoi Khimii.Different pagination.)Journal of Inorganic and Nuclear Chemistry.Journal of the Institute of Brewing.Journal of the Institute of Fuel.Journal of the Institute of Metals.Journal of the Institute of Petroleum.Journal of the Institute of Polytechnics, Osaka CityJournal of the Iron and Steel Institute.Journal of Madras University.Journal fur makromolekulare Chemie (replaced after vol.1, 1944, by Makromolekulare Chemie, vol. 1, 1947).Journal of Mathematics and Physics.Journal of Metals.Journal of Molecular Spectroscopy.Journal of the New Zealand Institute of Chemistry.Journal of Nutrition.1933 and 1947, Association and not Society).University.Tokyo.New Yorlc.(U.S. translation of Zhurnal obshchei Khimii.Different pagination.)University.J .Biochem. (Japan) .J . Biol. Chem. .J . Biol. Sci. .J . Chem. Educ. .J . Chenz: Met. Mining SOC.S. Afraca .J . Chem. Phys. .J . Chem. SOC. .J . Chem. SOC. Japau .J . Chem. SOC. Japan, Ind.Chem. Sect. .J . Chim. phys, .J . Chinese Chem. SOC. (For-J . Chromatog. .J . Colloid Sci. .J . Council Sci. I n d . Kes.,Australia .mosa) .J . Econ. Entomol. .J . Electrochem. SOC. .J . Electrochem. SOC. Japan .J . Fac. Sci., Hokkaido Im9.J . Fac. Sci. Univ., Tokyo .J .Fisheries Res. BoardJ . Franklin Inst. .J . Gen. Chena. (U.S.S.R.) .Univ. .Canada .J . Gen. Physiol. .J . Geol. .J . Histochem. Cytochem. .J . Imp. Coll. Chem. Eng. SOC.J . I n d . Eng. Chem. .J . Indian Chem. SOC. .J . Indian Chena. SOC., I n d .J . Indian Inst. Sci. .J . Inorg. Chem. (U.S.S.R.) .News Edn. .J . Inorg. Nuclear Chem. .J . Inst. Brewing .J . Inst. Faiel .J . Inst. Metals .J . Inst. Petroleum .J . Inst. Polytechnics, OsakaCity Univ. .J - Iron Steel Inst. .J . Madras Univ.J . makromol. Chem. .J . Math. Phys. .J . Metals .J , Mol. S9ectroscopy .J . New Zealand Inst. Chem.J . Nutrition . 438 PRINCIPAL REFERENCES USED.REFERENCE.J . Oil Colour Chemists’ Assoc.J . Opt. SOC. Amer. .J .Org. Chem. .J . Pharm. Belg. .J . Pharm. Pharmacol. .J . Pharm. SOC. Japan ,J . Phartnacol. .J . Phot. Sci. .J . Phys. and Chem. SolidsJ . Phys. Chem. .J . Phys. Chem. (U.S.S:R.)..J . Phys. Colloid Chem.J . Phys. Radium .J . Phys. Soc. Japan .J . Polarog. SOC. .J . Polymer Sci. .J . prakt. Chein.J . Proc. Inst. Chemists (India)J . Proc. Inst. Sewage Purif.J . Proc. Roy. SOC. New SouthJ . Iiamsay SOC. Chem. Eng. .J . Res. Inst. Catalysis,Hokkaido Univ. .J . Res. Nut. Bur. Stand. .J . Roy. Inst. Chem. .J . Roy. Microscop. SOC. .J . Roy. SOC. Arts .J , Rubber Res. .J . S. African Chena. Itest. .J . S . African Jnst. MiningWales .M e t . .J . Sci. Food Agric. .J . Sci. Hiroshima Unit). .J . Sci. Ind.Res., India .J . Sci. Instr. .J . Sci. Res. Inst., Tokyo .J . Soc. Chem. Ind. .J . Soc. Chent. Ind. (Japan) .J . SOC. Cosmetic Chemists .J . SOC. Dyers and ColouristsJ . SOC. Glass Technol.J . SOC. Leather Trades’Chemists .J . Textile Inst. .J . Washington Acad. Sci. .J a p . J. Exp. Med. .Jap. J . Mcd. Sci. Biol. .FULL TITLE.Journal of the Oil and Colour Chemists’ Association.Journal of the Optical Society of America.Journal of Organic Chemistry.Journal de Pharmacie de Belgique.Journal of Pharmacy and Pharmacology.Journal of the Pharmaceutical Society of Japan.Journal of Pharmacology and Experimental Thera-Journal of Photographic Science.Journal of Physics and Chemistry of Solids.Journal of Physical Chemistry.Journal of Physical Chemistry (U.S.S.R.).New Uork.(U.S. translation of Zhurnal fizicheskoi Khimii.Different pagination.)Journal of Physical and Colloid Chemistry (formerlyJournal of Physical Chemistry, and changed back tothat name with vol. 56, 1952).Journal de Physique et le Radium.Journal of the Physical Society of Japan.Journal of the Polarographic Society.Journal of Polymer Science.Joiirnal fur praktische Chemie (discontinued after vol.162, 1943; recommenced publication in 1954 withvol. 1 of a new series).Journal and Proceedings of the Institution of Chemists(India).Journal and Proceedings of the Institute of SewagePurification.Journal and Proceedings of the Royal Society of NewSouth Wales.Journal of the Ramsay Society of Chemical Engineers,University College, London.Journal of the Research Institute for Catalysis, HokkaidoUniversity.Journal of Research of the National Bureau of Standards(formerly Bureau of Standards Journal of Research).Journal of the Royal Institute of Chemistry.Journal of the Royal Microscopical Society.Journal of the Royal Society of Arts.Journal of Rubber Research (discontinued with vol.20,Journal of the South African Chemical Institute.Journal of the South African Institute of Mining andJIetallurgy. (Formerly Journal of the Chemical,Metallurgical and Mining Society of South Africa.)Journal of the Science of Food and Agriculture.Journal of Science of the Hiroshima University.Journal of Scientific and Industrial Research, India.Journal of Scientific Instruments.Journal of the Scientific Research Institute, Tokyo.Journal of the Society of Chemical Industry (dis-continued with vol.69, 1950).Journal of the Society of Chemical Industry (Japan)(name changed with vol. 51, 1948, to Journal of theChemical Society of Japan, Industrial ChemistrySection).peutics.1951).Journal of the Society of Cosmetic Chemists.Journal of the Society of Dyers and Colourists.Journal of the Society of Glass Technology.Journal of the Society of Leather Trades’ Chemists (namechanged with vol. 32, 1948, from Journal of theInternational Society of Leather Trades’ Chemists).Journal of the Textile Institute.Journal of the Washington Academy of Sciences.Japanese Journal of Experimental Medicine.Japanese Journal of Medical Science and BiologyPRINCIPAL REFERENCES USED 439REFERENCE.Jap.J . Pharmacol. .Japan Aitaljlsl .K . ned. Springstoflen fabviekenFULL TITLF.Japanese Journal of Pharmacology.Japan Analyst.Koninklijke nederlandsche SpringstoffenfabriekenAmsterdam.Kongelige danske Videnskabernes Selskab, Mate-matisk-fysiske Meddelelscr.Kongelige danske Videnskabernes Selskab, Matematisk-fysiske Skrifter.Icungliga Lantbruks-Hogskolens Annaler.Kongelige norske Videnskabers Selskabs, Forhandlinger.Kongelige norske Videnskabers Selskabs, Skrifter.Kungliga svenska Vetenskapsakademiens Handlingar.Khimicheskaya Nauka i Promyshlennost’. [See alsoKolloid-Beihefte (merged with Kolloid Zeitschrift, begin-Kolloid Zeitschrift.Kolloidnyi Zhurnal.[Scc also Colloid Journal (U.S.S.R.)].Krystallografiya.Kumamoto Pharmaceutical Bulletin.Kunststoffe.The Laboratory.Laboratory Practice.Leybold polarogra pliisch e Berichte.Liebig’s Annalen der Chemie. [See Annalen der ChemieMagazine of Concrete Research.Magyar Chemiai Folydirat (publication irregularbetween 1944 and 1948; name changed with vol. 56,1950, to Magyar KCmiai Foly6irat).Magyar KCmiai Folydirat.Makromolekulare Chemie.Manufacturing Chemist.Naterie plastiche.Meddelanden fr5n sveriges Kemiska IndustrikontorMededelingen van de vlaamse chemische Vereniging.Melliand Textilberichte.Memoirs of the College of Science, Kyoto University.Memoirs of the Faculty of Engineering, Hokkaido Uni-Memoirs. Faculty of Industrial Arts, Kyoto TechnicalMemoirs of the Faculty of Science, Kyushu University.Memoirs of the Institute of Scientific and IndustrialMCmorial des Poudres.Memoirs and Proceedings of the hlanchester Literary andPhilosophical Society.MCmorial du Service des Poudres (name changed withvol. 30, 1943, to MCmorial des Services chimiques de1’Gtat).MCmorial des Services chimiques de l’stat.Metal Finishing.Metal Industry.Metallforschung.Methods of Biochemical Analvsis.Chemical Industry (U.S.S.R.).]ning with vol.103, 1943).(Liebig’s) .](suppl. to Svensk kemisk Tidskrift).versj ty.University, Science and Technology.Series C-Chemistry.Research, Osaka University.Kgl. danske Videnskab.Selskab, Mat.-fys. Mcdd..Kgl. danske Videnskab. Scl-sknh. A.lat.-fys. Skvifter .Kgl. Lantbruks-HGgskol. Ann.Kgl. norske Videnskab.Selskabs, Forhandl. .Kgl. norske Videnskab:Selskabs, Skrifter .Kgl. svenska Vetenskapsahad.Handl. .Khim. Prom. .Kolloid-Beih. .Kolloid 2.Kolloid. Zhur. .Krystallografiya .Kum,amoto Phavm. Bull.Kunststofle .La bovntoryLab. Practice .Leybold polayog. Ber. .Mag. Co:zcrefe Res. .Magyar Cliem. FolydivatMagyar Kdm. FoLj$iratMakromol. Chem. .Manuf. Cher.n. .Materie idastiche .Medd. sceriges Kem. Indwstri-Mededel. vlaanz. chem. Vev. .Melliand Textilbev. .Mem. Coll. Sci., Kyoto Univ.Mein. Fac. Eng., HokkaidoUnizr. .Mem. Fac. Ind. Arts, KyotoTech. Univ., Sci. and Tech.Mern. Fac. Sci., KyushuUnio., Ser.C .Menz. Inst. Sci. Ind. Res.,Osaka Univ. .Mdna. Poudres .Merit. Proc. Manchester Lit.Phil. SOC. *n 4 h N . Service Poudves .koiitorMha. Services chim. &at .Metal FinishingMetal Ind.Metallforschung .Methods Biochem. Analysis .Metalluwia . Metallurgia. British Journal’of Metals.Microchem. J . . . Microchemical Journal440 PRINCIPAL REFERENCES USED.REFERENCE.Mie Med. J . .Mikrochem. Mikrochim. ActaMikrochim. Acta .Mineralog. Mag. .Mitt. chem. Forsch.-Inst.Wirtsch. dstew. .Mitt. deut. Pharm. Ges. .Modern PlasticsModern Textile Mag. .Mol. Physics .Monatsh. .Murex Rev. .Nachr. A kad. Wiss. Go'ttingen,NaftaNat. Res. Council Rcs: New'sNatural Sci. Report Ochano-Nature .Naturwiss.New Zealand J .Sci. Technol.*Nickel Bull. .Nuclear Sci. Abs. .NucleonicsNutrition Rev. .Nuovo cim.Math.+hys. Kl. .(Canada) .mizu Univ. .Olii, Grassi, Colori .Onderstepoort J . Vet. Res. .Onderstepoort J . Vet. Sci. .Org. Reactions .Org. Synlh. .dsterr. Chenz.-Ztg. .Paint Manuf. .Paint, Oil Chem. Rev.Paper Trade J . .Parfumerie u. Kosmetik .Perfumery Essed. Oil RecordPetroleum Processing .Pharm. Ada Helv. .Pharm. Bull. (Japan) .Pharm. J . .Pharm. Weekblad ;Pharm. Zentralhalle .Pharm. Ztg. .PharmaziePhil. Mag. .Phil. Trans. .Phys. and Chem. Earth .Phys. Fluids .Phys. Rev.Phys. 2.Phys. 2. Sowjetunion .FULL TITLE.Mie Medical Journal.Mikrochemie vereinigt mit Mikrochimica Acta (re-placed by hlikrochimica Acta after vol.40. 1952/53).Mikrochemie (replaced by Mikrochemie vereinigt mitMikrochimica Acta after vol. 24, 1038).Mikrochimica Acta.Mineralogical Magazine and Journal of the MineralogicalSociety.Mitteilungen des chemischen Forschungs-Instituten derWirtschaft t)sterreichs.Mitteilungen der deutschen Pharmazeutischen Gesell-schaft.Modern Plastics.Modern Textile Magazine.Molecular Physics.Monatshefte fur Chemie.Murex (Ltd.) Review.Nachrich ten der Akademie der Wissenschaften inNafta. Institut za Naftu. Zagreb.National Research Council Research News.Natural Science Report of the Ochanomizu University.Nature.Nat urwissenschaften.New Zealand Journal of Science and Technology.Nickel Bulletin.Nuclear Science Abstracts.Nucleonics.Nutrition Reviews.Nuovo cimento.Olii minerali, Grassi e Saponi, Colori e Vernici.Onderstepoort Journal of Veterinary Research.Onderstepoort Journal of Veterinary Science andAnimal Industry (name changed in 1951 to Onder-stepoort Journal of Veterinary Research).Organic Reactions.Organic Syntheses.Osterreichische Chemiker-Zeitung.Paint Manufacture, incorporating Paint.Paint, Oil and Chemical Review.Paper Trade Journal.Parfumerie und Kosmetik.Perfumery and Essential Oil RecordPetroleum Processing.Pharmaceutica Acta Helvetiae.Pharmaceutical Bulletin. (Japan.)Pharmaceutical Journal.Pharmaceutisch Weekblad.Pharmazeutische Zentralhalle fur Deutschland (notPharmazeutische Zeitung.Pharmazie.Philosophical Magazine.Philosophical Transactions of the Royal Society.Physics and Chemistry of the Earth.Physics of Fluids.Physical Review.Physikalische Zeitschrift (discontinued with vol.45,Physikalische Zeitschrift der Sowjetunion (discontinued(Bound with Archiv der Pharmazie.)Gottingen, Mathematisch-physikalische Klasse.published between 1944 and 1947).I 045).with vol. 13, 1938)PRINCIPAL REFERENCES USED. 441REFERENCE.PhysicaPlant Physjol. :Powder Met. Bull. .Prakt. Chemie .Proc. . . . .Proc. Acad. Natural Sci.Proc. Acad. Sci. iU.S.S.R,)PhiladelphiaFULL TITLE.Physica.Plant Physiology.Powder Metallurgy Bulletin.Praktische Chemie. Wien.Proceedings of the Chemical Society.Proceedings of the Academy of Natural Sciences ofProceedings of the Academy of Sciences of the U.S.S.R.(U.S.translation of Doklady AkademiiProceedings of the American Academy of A r t s andProceedings of the American Society of BrewingProceedings of the Cambridge Philosophical Society.Proceedings of the Chemical Society.Proceedings of the European Brewery Convention.Proceedings of the Geologists’ Association.Proceedings of the Imperial Academy (Tokyo) (namechanged with vol. 21,1945, to Proceedings of the JapanAcademy).Proceedings of the Indian Academy of Sciences.Proceedings of the Indiana Academy of Science.Proceedings of the Japan Academy.Proceedings, koninklijlre nederlandsche Akademie vanProceedings of the London Mathematical Society.Proceedings of the National Academy of Sciences of theProceedings of the National Institute of Sciences ofProceedings of the Physical Society of London.Proceedings of the Plastics and Polymer Group,Society of Chemical Industry.Proceedings of the Royal Irish Academy.Proceedings of the Royal Society.Proceedings of the Royal Society of Edinburgh.Proceedings of the Society for Experimental Biology andProceedings of the Soil Science Society of America.Proceedings and Transactions of the Royal Society ofProgress in Biophysics and Biophysical Chemistry.Progress in the Chemistry of Fats and Other Lipids.Progress of Theoretical Physics. (Japan.)Przemysl Chemiczny.Publications of the American Association for thePublications CERCHAR (Centre d’ztudes et RecherchesPublicaciones del Instituto de Quimica “ Alonso Barba.”Pyrethrum Post.Quarterly Journal of the Geological Society of London.Quarterly Journal of Pharmacy and Pharmacology (re-placed in 1949 by Journal of Pharmacy andPharmacology, beginning with vol.1).Quarterly Reviews.Quimica e Industria.Radiation Research.Recueil des Travaux chimiques des Pays-Bas.Recent Progress in Hormone Research.Philadelphia.New York.Nauk S.S. S. R.Sciences.Chemists.Different pagination .)Wetenschappen.United States of America.India.Medicine.Canada.Advancement of Science.des Charbonnages de France).Proc. Amer. Acad. Arfs Sci.Proc. Amer. Soc. BrewingProc. Cambridge Phil. Soc. .Proc. Chain. SOC.Proc. European Brcw. Conv.Proc. Geologists’ Assoc. ,Proc. I m p . Acud.(Tokyo) .Chemists. .Proc. Indian Acad. Sci. .Proc. Indiana Acad. Sti. .Proc. Japan Acad. .Proc. k. ned. Akad. Weten-Proc. London Math. SOC. .Proc. Nat. Acad. Sci. U.S.A.schap. .Proc. Nat. Inst. Sci. India .Proc. Phys. SOC.Proc. Plastics Pdyvner Group,Proc. Roy. Irish Acad. .Proc. Roy. SOC. .Proc. Roy. SOC. Edinburgh .Proc. Soc. Exp. Biol. Med. .PYOC. Soil Sci. SOC. Amer. .Proc. Trans. Roy. SOC. CanadaProgr . Biophysics Biop hys .Progr. Chem. Fats and OtherProgr. Theor. Phys. (Japan)Przemysl Chem. .Publ. An2er. Assoc. Adv. Sci.SOC. Chein. I n d . .Chem. .Lipids .Publ. CERCHAR .Publ. Inst. Qulm. AlonsoPyrethrum Post .Quart. J Geol. Soc. .Quart. J . Pharm. Pharinacol.Barba .Quart. Rev.Quimica e Industria .Radiation Res..Rcc. Trav. chim.Recent Progr. Hormone Re442 PRINCIPAL REFERENCES USED.REFERENCE.RecherchesRend. Accad. Sci. j i s . mat.,Report Brit. Assoc. .Report Fac. Pharm.,Kanazawa Univ. .Report Sci. Res. Inst. (Japan)Report Takainine Lab.Reports Gout. Chem. I n d . Res.Reports “ J . Stefan ” Inst. .Reports Progr. Appl. Chem. .Reports Progr. Phys. .Reports Slovenian Acad. Sci.Arts .Research .Research Today .Rev. Asoc. bioquinz. argentinaRev. Chiin. (Acad. R.P.R.) .Rev. Cienc. apl. .Rev. Coal T a r Teclmol. .Rev. Fac. Cienc. quiin., Univ.nac. L a Plata .Rev. Fac. Farm. Bioquim.,Univ. nac. mayor S a nMavcos .Rev. Fac. Quim., Univ. nac.mayor S a n Marcos .Rev. Fac. Sci. Univ. IstanbulNapoli .Inst., Tokyo .FULL TITLE.Recherches.Rendiconti dell’Accademia delle Scienze fisiche eReport of the British hssociation for the AdvancementReport (Annual) of the Facultv of Pharmacy, KanazawaReport of the Scientific Research Institute.Report (Annual) of the Takamine Laboratory.Reports of the Government Chemical Industrial Re-Reports “ J.Stefan ” Institute.Reports on the Progress of Applied Chemistry.Reports on Progress in Physics.Reports of the Slovenian Academy of Sciences andArts.Research.Research Today.Revista de la Asociaci6n bioquimica argentina.Revue de Chimie (Acaddmie de la R6publique Popu-Revista de Ciencia aplicada.Review of Coal Tar Technology.Revista de la Facultad de Ciencias qufmicas (QufmicaRevista de la Facultad de Farmacia y Bioquimica,Revista de la Facultad de Quimica, Universidad nacionalRevue de la Facultb des Sciences de 1’UniversitCRevue gCnCrale du Caoutchouc.Revue de 1’Industrie minbrale.Revue de 1’Institut fransais du PBtrole et Annales desCombustibles liquides.Reviews of Modern Physics.Review of Physical Chemistry of Japan.Revue des Produits chimiques.Reviews of Pure and Applied Chemistry (Royal Aus-tralian Chemical Institute).Revista de Quimica industrial.Revista de Qufmica pura e aplicada.Revue scientifique.Review of Scientific Instruments.Review of Textile Progress.Revista de Chimie (Roumania).Ricerca scientifica.Rieclistoffe und Aromen (as from January, 1955, re-places Atlierische ole, Riechstoff e, Parfiimerien,Essenzen, und Aromen).Roczniki Chemii (not published between 1939 and1946).Rohm and Haas Reporter.Royal Institute of Chemistry Lectures, Monographs, andSouth African Industrial Chemist.South African Journal of Science.Sbornik Statey PO obshchei Khimii (a supplementaryjournal to Zhurnal obshchei Khimii, 1953, intendedto reduce the arrears in publication).Schweizerische Apotheker-Zeitung.Scientific American.Scientific Journal of the Royal College of Science.Science of Light.(Institut of Optical Research, Tokyo).matematiche, Napoli.of Science.University .(Japan.)search Institute, Tokyo.laire Roumane) .y Farmacia).Universidad nacional mayor de San Marcos.mayor de San Marcos.d’Istanbu1.Universidad nacional de La Plata.Reports.Rev.gdn. Caoutchouc .Rev. I n d . minkrale .Rev. Inst. frang. Pktrole .Rev. Mod. Phys.Rev. Phys. Chem. Japan .Rev. Prod. chim.Rev. Pure Appl. Chem.Rev. Quim. industrial .Rev. Quim. pura apl. .Rev. sci. .Rev. Sci. Instr. .Rev. Textile Progr. .Revista de Ckimie (Roumania)Ricerca sci.Riechstofle u. Arornen .(Australia) .Roczniki Chem. .Rohm and Haas Reporter .Roy. Inst. Chem. Lectures,Monographs, and ReportsS. Afvican I n d . Chemist .S. African J . Sci. .Sbornik Statey p o obshcheiSchweis. Apoth.-Ztg. .Sci. American .Sci. J . Roy. Coll. Sci.Khim. .sci. Light PRIXCIPAL REFERENCES USED. 443REFERENCE.Sci. Papers College Gen. Edzcc.,Sci. Papers Inst. Phys. Chem.Univ. Tokyo .Res. (Tokyo) .Sci.Proc. Roy. Dublin Soc. .Sci. Progr. .Sci. Reports Res. Inst.,Sci. Reports Saitama Univ. .Sci. Reports SOC. Res. Theor.Sci. Reports TShoku Univ. .Sci. Sinica .Sci. Tools .TShoku Univ.Chem. .Science .Science and Culture .Sitzungsber. A kad. TViss.W i e n .Sitzungsber. Ges. Befijrd. ges.Natuvwiss. MarburgSitzungsber. iisterr. Akad.Wiss. Abl. I I .Sinithsonian Misc. Coll. .Smokeless Air .Soap .Soc. Sci. Fennica, Coinmt-nta-tiones Phys.-Math. .Soil Sci. .Spectrochiin. A cia .Sperimentale .Sperimentale, Sez. Chim. biol.Staiuke .Staiw Tecltnol. .Studii si Cercetdri Chim.Studzz sz Cercetdri Chim.(Acud. P.P.R.) .( F i l . Cluj.) .Studii si Cercetdri Sti. Chirn.( F i l . Iasi.) .Studii si Cercetciri Sti., Ser.ISugar .Siiddezit. Apoth.-Zfg. .Suotiien Kem. .Svensk kern. Tidskr. .Svensk Papperstidn. .Szerves KPm. lionf. DebrecenTaste Odor Control J . .Tcchnol. Reports Osaka Univ.Technol. Reports Tdhoku Univ.TetrahedTton .FULL TITLE.Scientific Papers of the College of General Education.University of Tokyo.Scientific Papers of the Institute of Physical andChemical Research (Tokyo) [discontinued with vol.42, 1047; replaced with vol. 43 by Journal of theScientific Research Institute (Tokyo)].Scientific Proceedings of the Royal Dublin Society.Science Progress.Science Reports of the Research Institute, T6hokuUniversity.Science Reports of the Saitama University.Science Reports of the Society for the Research ofTheoretical Chemistry.Science Reports of the TGhoku University.Scientia Sinica.Science Tools.The LKB Instrument Journal.Stockholm.Science.Science and Culture.Sitzungsberichte der Akademie der Wssenschaften inSitzungsberichte der Gesellschaft zur Beforderung derSitzungsberichte osterreichische Akademie der Wisscn-Smithsonian (Institution) Miscellaneous Collections.Smokeless Air.Soap and Chemical Specialties.Societas Scientiorum Fennica, Commentationes Physico-Soil Science.Spectrochimica Acta.Lo Sperimentale, Archivio di Biologica normale etLo Sperimentale, Archivio di Biologica normale etDie StarkeStain Technology.Studii si Cercetari de Chimie. (Acadernie RepubliciiPopulare Romine.)Studii si Cercetari de Chimie. (Academia RepubliciiPopulare Romine.Filizla Cluj.) Formerly Studii siCercetgri Stiintifice. (Academia Republicii Popu-lare Romine. Filiala Cluj.) Name changed from1956.Studii si Cercetgri Stiintifice. Chimie. (AcademiaRepublicii Populare Romine. Filiala Iasi.) Partlyreplacing Studii si Cercetiiri Stiintifice (Iasi). Seria1. Stiinte Matematice, Fizice, Chimice si Technice.Name changed from 1956.Studii si CercetHri Stiintifice, Seria I . Stiinte Mate-matice, lkice, Chimice si Technice.Sugar.Siiddeutsche Apotheker-Zeitung (merged with DeutscheSuomen Kemistilehti (formerly also Acta ChcmicaSvensk kemisk Tidskrift.Svensk Papperslidning.Szerves Keniiai Konferencia Debrecen.Taste and Odor Control Journal.Technology Reports of the Osaka University.Technology Reports of TGhoku University.Tetrahedron.iVien (discontinued with vol.131, 1923).gesamten Natunvissenschaften zu Marburg.schaften. Abteilung 11.(National Smoke Abatement Society.)Mathematicae.Pat ologi ca.Patologica, Sezione di Chimica biologica.Apotheker-Zeitung after vol. 90, 1950).Fennica).International Journal of Organic Chem-istry444 PRINCIPAL REFERENCES USED.REFERENCE. FULL TITLE.Textile Res. J . . . Textile Research Journal.Tidsskr. Kjemi Bergvesen Met.TGhoku J . Ex$. Med. . . TBhoku Journal of Experimental Medicine.Trans. Amer. Assoc. Cereal Transactions of the American Association of CerealTrans. Amer. SOC. MetalsTrans. Brit. Ccram. SOC.Trans. Chalmers Univ. Transactions of Chalmers University of Technology,Trans.Faraday SOC. . . Transactions of the Faraday Society.Trans. Inst. Chem. Engrs. .Trans. Inst. Mining Engrs. .Trans. Plastics Inst.Trans. Proc. Inst. Rubber Ind.Tvans. Roy. SOC. Canada .Trans. Roy. SOC. Edinburgh .Trans. Wisconsin A cad. Sci.Trudv Inst. Krist.. Akad. NaukTidsskrift for Kjemi Bergvesen og Metallurgi.Chem. . . Chemists. . . Transactions of the American Society of Metals.Transactions of the British Ceramic Society.Tcchnol., Gothenburg . Gothenburg.Transactions of the Institute of Chemical Engineers.Transactions of the Institution of Mining Engineers.Transactions of the Plastics Institute.Transactions and Proceedings of the Institution of theTransactions of the Royal Society of Canada.Transactions of the Royal Society of Edinburgh.Transactions of the Wisconsin Academy of Sciences,Rubber Industry.Arts and Letters.S.S.S.R.Trudy Kom.analit. Khiin.,Akad. Nauk S.S.S.R. .Trudy Instituta Kristallografii, Akademii Nauk S.S.S.R.Trudy Komissii PO analiticheskoi Khimii, AkademiiNauk S.S.S.R.Ukrain. biokhim. Zhur. .Ukrain. khim. Zhur. .Unicam Spectrovision .Uspckhi Khim. .Verhandel. k. ned. Akad.Wetenschap., A f d . Natuurk.Vestnik Slovensk. Kern..DruStva .Vitamins and Hormones. .Voprosy Med. Khim. .Wallersfein Lab. Comnz. .Wien. Chem.-Ztg. .World’s Paper Trade Rev. .Yeast .Z. Acker- u. PfEanzenbau .2. analyt. Chem.2. angew. Chem. .2. angew. Mineralog. .2. angew. Physik .2. anorg. Chem.Z. Biochem. .Z .Biol. .Z. Elektrochem. .2. Krist. .2. Lebensm.-Untersuch. .Z. Metallkunde .2. Naturforsch. .Ukrainskii biokhimicheskii Zhurnal.Ukrainskii khimicheskii Zhurnal.Unicam Spectrovision.Uspekhi Khimii.Verhandelingen der koninklij ke nederlandsche AkademieVestnik Slovenskega Kemijskega DruHtva.Vitamins and Hormones.Voprosy Meditsinskoi Khimii.van Wetenschappen, Afdeling Natuurkunde.Wallerstein Laboratories Communications.Wiener Chemiker-Zeitung (name used between 1942 andWorld’s Paper Trade Review.1947 for Osterreichische Chemiker-Zeitung) .Yeast.Zeitschrift fur Acker- und Pflanzenbau.Zeitschrift fur analytische Chemie.Zeitschrift fur angewandte Chemie (name changed withZeitschrift fur angewandte Mineralogie (discontinuedZeitschrift fur angewandte Physik.Zeitschrift fur anorganische und allgemeine Chemie.Zeitschrift fur Biochemie (discontinued after vol. 41,Zeitschrift fur Biologie.Zeitschrift fur Elecktrochemie (und angewandte physikal-ische Chemie) [name changed with vol. 56, 1952, toZeitschrift fur Elektrochemie. (Berichte der Bunsen-gesellschaft fur physikalische Chemie.)]Zeitschrift fur Ifiistallographie (suspended with vol. 106,1945 ; recommenced publication with vol. 106, 1954;pagination apparently continuous).Zeitschrift fur Lebensmittel-Untersuchung und -For-schung (not published between 1944 and 1948).Zeitschrift fur Metallkunde.Zeitschrift fur Naturforschung.vol. 45, 1932, to Angewandte Chemie).after vol. 4, 1943).1942)PRINCIPAL REFERENCES USED. 445REFERENCE.Z . phys. Chew (Frankfurt) .2. phys. Chem. (Leipzig) .Z . Physik .Z . physiol. Chem. .Z . Vitamin-, Hormon-, u. Fer-Z . Vitaminforsch. .mentforsch. .Z . Wirtschaftsgruppe Zuckev-2. uriss. Phot. .ind. .Zavodskaya Lab..Zeszyty Nauk. Politech. Eodz.Zhur. analit. Khim. .Zhuv. eksp. teor. Fiz. .Zhur. fiz. Khim.Zhur. khim. Promyshl. .Zhur. nauk. priklad. Fotograf.Zhur. neorg. Khim. .Zhur. obshchei Khim. .Kinemat. .Zhur. priklad. Khim. .Zhur. trkh. Fiz. .FULL TITLE.Zeitschrift fur physikalische Chemie (FrankfurterAusgabe).Zeitschrift fur physikalische Chemie (Leipzig) (notpublished between vol. 194, 1944, and vol. 194, 1950).Zeitschrift fur Physik (not published between vol. 123,1944. and vol. 124, 1947).Zeitschrift fur physiologische Chemie (Hoppe-Seyler’s) .Zeitschrift fur Vitamin-, Hormon-, und Fermentfor-schung.Zeitschrift fur Vitamjnforschnng (name changed withvol. 19, 1947, to Internationale Zeitschrift fur Vitamin-forschung) .Zeitschrift der Wirtschaftsgruppe Zuckerindustrie(Verein der Deutschen Zucker Industrie) (discontinuedafter vol. 94, 1944).Zeitschrift fur wissenschaftliche Photographie, Photo-physik. und Photochemie.Zavod skaya Labora tori ya.Zeszyty Nauliowe Politechniki fodzkiej.Zhurnal analiticheskoi Khimii. [See also Journal ofAnalytical Chemistry (U . S. S. R.)] .Zhurnal eksperimental’noi i teoreticheskoi Fiziki.Zhurnal fizicheskoi Khimii.Zhurnal khimicheskoi Promyshlennosti (discontinuedafter vol. 18, 1941).Zhurnal nauknoi i prikladnoi Fotografii i Kinemato-grafii.Zhurnal neorganicheskoi Khimii. [See also Journal ofInorganic Chemistry (U.S.S.R.).:Zhurnal obshchei Khimii. [See also Journal of GeneralChemistry (U.S.S. R.)].Zhurnal prikladnoi Khimii. [See also Journal of AppliedChemistry (U. S.S. R. )] .Zhurnal tekhnicheskoi Fiziki.~~~PRINTED IN GREAT BRITAIN BY RICHARD CLAY A N D ComPAur, LTD.BUNGAY, SUFPOLK

ISSN:0365-6217    

DOI:10.1039/AR9575400429

出版商:RSC    

年代:1957

数据来源: RSC