摘要:

ANNUAL REPORTSPROGRESS O F CHICMISTRY.ON THANNUAL REPORTSP. W. ASTON, M.A., D.Sc., F.R.S.H. V. A. BRISCOE, D.Sc.H. M. DAWSON, D.Sc., Ph.D.ON THEJ. KENNER, Ph.L)., D.Sc.C. AINSWORTII hl ITCHELL, M. A.H. J. PAGE, M.B.E., B.Sc.PROGRESS OF CHEMISTRYF O R 1922.ISSUED BY THE CHEMICAL SOCIETY.$ommifttt of @ublirafion :A. J. ALLMANU, M.C., D.Sc.0. L. BRADY, D.Sc.A. W. CrtossmY, C.M.G., C.B.E.,C. H. DESCH, D.Sc., Ph.D.I. M. HEILBKON, D.S.O., D.Sc., Ph.D.J. T. HEWI'rT, M.A., D.Sc., Ptr.D.,H. KING, D.Sc.D. Sc., F. R.S.F. H.S. ,r. c. IRVINF,, c.B.E., D.s~., F.R.S.T. $1. LOWRY, C. R. E. , D.Sc., F.R.S.J. W. MCBAIN, K A . , P1l.I).J. I. 0. MASSON, Ill. BE., D.Sc.J. C. PHILIP, O.B.E., D.Sc., Ph.D.,R. H. PICRARD, D.Sc., Ph.D., F.R.S.N. V.SIDGWICK, M.A., Sc.D., F.R.S.J. F. THORPE, C.B.E., D.Sc., F.R.S.Sir JAMES WALKEti, D.Sc., LL.L).,F. R. S.F. R. S.$bitor :A. J. GREENAWAY3srrisfant Qbifox :CLARENCE SMITH, D. Sc.%Stii&nTt :A. A. ELDRIDGE, B.Sc.(ynbexer :MARGARET LE PLA, B.Sc.VOl. XIX.L O N D O N :GURNEY & J A C K S O N , 33 PATERNOSTER ROW, E.C. 41923PRINTED IN Gma.r BRITAIN BYRICHARD CLAY & SONS, Lixrrm,nuN(:AY, SUI~WOLKCONTENTS.PAGEGENERAL AND PHYSICAL CHF’,MISTRY. By H. M. DAWRON, D.SP.,Ph.D. . . . . . . . . . . . 1INORGANIC CHEMISTRY. By H. V. A. BRIFCOE, D.Sc. . . . 30ORGANIC CHEMISTRY :-Part ~.-ALIPHATIC DIVISION. By W. N. HAWORTH, D.Sc., Ph.D. . 60Pait II.-HOMOCYCLIC DIVISION. By R. ROBINSON, D.Sc., F.R.S. . 85Part III.-H~rmocYcLTc DIVISION.By J. KEXNER, Ph.D., TI.%. . 125ANALYTICAL CHEMISTRY. By C. AINSWORTH MITCHELL, M.A. . 164PHYSIOLOGICAL CHEMISTRY. By J . C. DRUMMOXD, D.Sc. . . 182AGRICULTURAL CHEN ISTRY AND VEGETABLE PHYSIOLOGY.By H. J. PAGE, M.B.E., B.Sc. . . . . . . . 203CBYSTALLOCIRAPHY AND MINERALOGY. By A. E. H. TUTTON,M.A., D.Sc., F.R.S. . . . . . . . . 2 3 4SUR-ATOM IC PHENOMENA AND RADIOACTIVITY. By F. W. As.roN.M.A., D.Sc., F.R.S. . . . . . . . . . 26ABBREVIATED TITLE.A , . . . . .Amer. Chem. J. . . .Amer. J. Bot. . . .Amer. J. Dis. Child. . .Amer, J, Hygiene . .Amer. J. Physiol. , .Amer. J. Sci. . . .Amer, Min. . , ,Anal. Assoc. Quim,. ArgentinaAn.al. Fis. Quim. . .Analyst . . . .Annalen . . . .Ann. AppZ. Biol.. .Ann. Bot. . . . .Ann. Chim. a.nnl. . .Ann. Physik . . .Ann. Phytopath. SOC. Japan.Ann. Report . . .Arch,. exp. Path. Pharm. .Arch. Farm. sperim. Xci. .Arch. Phmrm. . . .ArchSchifs u. Tropenhygien cArch. Suikerindus. Ned. Ind.Arkiv. Kem. Min. Geol. .Atti R. Accad. Lincei . .Ber. . . . . .Ber. Dezct. bot. Gcs. . .Ber. Deut.pharm. Ces. .Astrophys J. . .Bed. Klin. Wochenschr. .Bied. Zenlr. . . .Biochsm. J. . . .Biochem. 2. . . .BoU. CJAim. farm . .Brd mstof- Chem . . .Brit. Assoc. Rep. . .Brit. Med. J. . . .Brit. Pat; , . . .RuI. SOC. Chim. Romania .BUZZ. Acad. Sci. Cracovie .REFERENCES.TABLE OF ABBREVIATIONS EMPLOYED IN THE* The year is not inserted in references t o 1922.JOURNAL.Ahstracts in Journal of the Chemical Society. *American Chemical Journal.American Journal of Botany.American Journal of Diseases of Children.American Journal of Hygiene.American Journal of Physiology.American Journal of Science.American Ifineralogist.Anales de la Asociacion Quimica Argentina.Anales de la Sociedad Espanala Fisica y Quimica.The Analyst.Juotus Likbig’s Annalen der Chemie.Annals of Applied Biology.Annals of Botany.Annales de Chimie anal?.tiqne appliqnke h 1’IndnstriesAnnalen der Physik.Annals of the Phytopathic Society, Japan.Annual Reports of the Chemical Society.Archiv fur experimentelle Patliologie und Pharma-Arcliivio di Farmacologia sperinientale e Scienze affini.Archiv der Phannazie.Archiv Schiffs-und Tropen-Hygiene.Archiv voor de Suikeriridustrie in Nederlandsch-Indie.Arkiv for Kemi, Mineralogi och Geologi.Astrophysical Journal.Atti della Rede Accadeniia Nazionale dei Lincei.Berichte der Deutschen ( liemischen Gesellschaft.Berichte dcr Deutsclien botanischen Gesellschaft.Berichte der Deutschen pharmazeutisclien Gesell-Berliner Klinische Wochenschrift.Biederinann’s Zentralblatt fiir Agrikulturchemie undThe Biochemical Jonmal.Riochemische Zeitsvhrift.Bolletino Chimico farmaceutico.13rennstoff Chemie.Report of the British Association for the Advance-ment of Science.British Medical Journal.Hritish Patent.Ruletinul Societatei de Chimie din Itomlnia.Bulletin International-AcadBmie des Sciences deB l‘Agriculture, A In PharmacBie et B la Riologie.kologie.scha ft.rationellen Landwirtschafts-Betrieb.Cracoviviii TABLE OF ABBREVIATIONS EM PLOYED IN THE REFERENCES.ABBREVIATED TITLE.Bull.Bur. Biotechb. . ,BUZZ. Jolzns Jfopkins liosp. .Bull. Sci. Pharmacol. .Bull. SOC. chin?,.Bull. Soc. c7zim. L'ely.Bull. Soc. chim. Biol.Canadu Med. Assoc, .I.Chem. Listy . .Chem. and Xet. Eny. .Chcm. News . .Chem TC'eekblad .Chem. Ztg. . IChem. Zentr. . .Chim. et J d . . .C'ompt. rend. .Compt. rend. Xoc. Biol.U.3.-P. . I .Ferniefitforsch. . .Gazzetta . . .Ceol. For. Forh. . .Giorn. Chign. Ind. Appl.Wela. Cham. Ada . .Iqiternat. Milt. BodeiLkzcnde .J. Agrie. Res. , . .J. Agric. bci. . . .J. Anwr. Ohem. Soc. . .J. Amer. Med. Assoc. . .J. Assoc. Of. Agr. Chem. .J.Bact. . . . ,J. Biochem. (Japan) , ,J. Biol. Chein. . . .J. Chem. Id. Japn (orTokuo) . . .J. Chlm: Xoc. Japa?z. .J. Chim.phys. . .J. Coll. Agric. HokaidoJ. Expcr. Mcd. . .J. Franklin lnst. .J. Gen. Physwl. . .J. Ind. Eng. Chem. .J, Jmt. Breuing .J. Laihdw. . . .J. Min. Ayric. . .J. Opt. Soc. AnLer. .J. Pharm. Chim. .J. Phann. Soc. Jupari.J. Physaeul Chem. .J. Physiol. . .J. pr. CJbem. . .J. Xws. PJLYS. Clwm. SOC.J . SOC. Chcitz. Ind. .J. Washington Acntl. Sci.Kentucky Eq. Stn. Bul .61011. Chem. Beiheflr .Kolloid 2. . . .J. Phys. Radium .Landw. Jahrb. . . .JOURNAL.Bulletin of the Bureau of Biotechnology.Bulletin of the Johns Hopkins Hospital.Bulletin des Sciences Pharmacologiques.Bulletin de la Soci6t6 chiniique de France.Bulletin de la Sociktb chimique de IMgiquc.Bulletin de la Socidtd de Chimie biologiyue.Journal of the Canadian Medical 'Associatioii.Chemick6 Listy pro V6du a Prbmysl.Chemical and Metallurgical Engineering.Chemical News.Chemisch Weekblnd.Chemiker Zeitung.C hemisches Zent ralblatt.Chimie e t Industrie.Coinptes rendus hebdonia.daiieu des Sdarrces deComptes rendus hebdomadaires de Sbaiices de laDeutsches Reicku-Patent.Fermentforschung.Qazzetta chimica italiana.Geologiska Poreningens i Stockholm Forhandliigar.Giornale di Chimica Industriale ed Applicata.Helvetica Chimica Bcta.Internationale Mitteiluugen fur Bodeukunde.Journal of Agricultural Research.Journal of Agricultural Science.Journal of the American Chemical Society.Journal of the American Medical Association.Journal of the Association of Official AgriculturalJournal of Bacteriology.Joiirnal of Biochemistry (Japan).Journal of Biological Chemistry.Journal of Chemical Industry, Japan.Journal of the Chemical Society of Japan.Journal de Chimie physique.Journal of the College of Agriculture, Hokaido.Journal of Experimental Medicine.Journal of the Franklin Institute.Journal of General Physiology..lourns1 of Ilitlustrial and E~~gineering Cheinistry.Journal of the Institute of Brewing.Journal fur Landwirtschaft.Journal of the Ninistry of Agriculture.Journal of the Optical Society of America.Journal de Pharmacie et dt: Chimie.Journal of the Pharmaceutical Society of Japan.Journal of Physical Chemistry.Journal de Physique et le Radium.Journal 01' Physiology.Journal fur yiaktische Cheniie.Journal of the Physical and Chemical Society ofJouriial of the Society of Cheniical Industry.Journal of the Washington Academy of Sciences.Kentucky Experiniental Station Bulletin.Kolloidchemische Beihefte.Kolloid Zcitschrift.Landwirtschaftliche Jahrbiicher.1'Acaddmie dea Sciences.Soci6tt5 de Biologic.Chemists.RussiaTABLE OF ABBREVIATIONS EMPLOYED IN THE REFERENCES.i XAEBRICVIATEI) TITLELandw. Versmhs-Stal. .Mcdd. K. Velenekapsaknd.Nobcl-Inst. . . .Nrm. Naw chcste r Phi I. SOC.illickigan Agric. Exp. Sta. .Min. Mag. . . .Momtsh * . . .Mon. Sci. , . . .Naehr. Ges. CViss. GottingenNatzcrwiss .. . .Oesterr. Chem. W g . . .Oregon Agric. Exp. Sta. Bull.P. . , . .Phnrm. Weekblmd . .Phurfm. Zentr.-h. . .Phil. Mag. . . .Phil. Trans. . . .Physical Reu. . . .Proc. Antcr. Phil Soc. .Proc. Cam. Phil. SOC. . .Proc. K. Akad. Wefensch.Amsterdam . . .Proc. Nut. Acnd. Sci. . .Proc. Physical Soc. . .['roc. Roy. Soc. . . .Proc. Soc. Exp. Biol. Xed. .Bec. trav. chim. . . .Physikal. Z. . .Kev. Mdt. . . . .Schzuciz. Apolh. Zlg. . .Sci. Proc. A. Diibliib SOC. .Sitzzcngs bcr. AIcucl. 1Viss.Wien . . . .Sitzungsbcr. Preuss. Akad.Wiss. Berlin . . .Skand. Arch. Physiol. .Soil Sci. . . . .Svensk. Kern. Tidskr. . .T . . . . . .Trans. Faraday SOC. . .Trans. A'oy. Soc. C'unadn .U. S. Geol. Xurvey Prof. PaperU.S. Pat. .. . .Ver. Deut. Physikal. Ges. .1Vf.w. Yepiifentl. SiemensKonzern . . . .Z. anal. Chern. . . .Z. nngew. Chem.. . .Z. anorg. Chem. . . .Z. Biol. . . .Z. Elektrochern. . . .JOITRSAI,.Die Landwirtschaftlichen Versuchs-Stationen.llleddelanden frAn Kongl-VetenskapsakademienvMemoirs and Proceedings of the Manchester LiteraryMichigan Experimental Station Bulletin.Mineralogical Magazine aud Journal of theMonatshefte fiir Chemie nnd verwandte Theile andererMoniteur Scientifique.Nachrichten YOU der Gesellscliii ft der Wissenschaftenzu Gottingen.1 Xe Naturwissenschaften.Oesterreichiscbe Chemikrr-Zeitung.Oregon Experimental Station Bulletin.Proceedings of the Chemical Society.Pharmaceutisch Weekblad.Pharmazeutische Zentralhalle.Nobel- Institut.and Philosophicnl Society.Mineralogical Socicty.Wissenschaften .Philosophical Magazine (The London, Edinburgh andDublin).Philosophical Transactions of the Royal Society ofLondon.Physical Review.Physikalische Zeitsclirift.Proceedings of the American Philosophical Society.Proceedings of the Cambridge Philosophical Society.Koniti klijke Akadeniie van Wetenschxlbpt?ii te Bmster-dam.Proceedings (English version).Proceedings of the National Academy of Sciences.Proceedings of the Physical Society of London.Proceedings of the Royal Society.Proceedings of tlie Society of Experimental Biologyltecueil des travaux cliimiques iles Pays-Bas et de laRevue de MQtallurgie.Schweizerische A otheker Zeitung.Scientific Proceec!ngs of the KoyJ Dublin Society.Sitzungsberichte der Akadernie dcr W issenschaftenSitzungsberichte der Preussisclieii Akaclemie derSkandinavisches Archiv fur PhyaioIogie.Soil Science.Svensk Kemist Tidskrift.Transactions of the Chemical Society.Transactions of the Faraday Society.Transactions of the Royal Society of Canada.United States Geological Survey Professional Paper.United States Patent.Verhandlungen der deutschen physikalischen Gesell-Wissen schaftliche Veroffen tlichungen aus dem SiemensZeitschrift fur analytische Chemie.Zeitschrift fiir angewandte Chemie.Zeitschiift fur anorganische und allgeiiieine Chemie.Zeitschrift fur Biologie.Zeitschrift fiir Elektrochemie.and Medicine.Relgique.Wien.Wissenschaften zu Berlin.schaft.KonzernX TAELE OF ABBREVIATIONS EMPLOYED I N THE REFERENCES.ARBREVIATED TITLE.Z. yes.Xchiess-u. Spreng-stofw. . . . .%. Hyg. . . . .Z. Melallk. . . . .2. Xuhr.-G'ettncsaitL. . .Z. Physik . . . .%. physikal. Chem. . .%. ph ysikul. Chew. Untery.%. physiol. CJma. . *%. wiss. Photachewi. . .JOURNAL.Zeitschrift fur das gesamm te Schiess-und Spreng-Zeitschrift fur Hygiene und Infektionskranliheiten.Zeitschrift fiir Met allkunde.Zeitschrift fiir Unt ersuchung tler Nahrugs- undGennssinittel.Zeitachrift fur Yhysik.Zeitschrift fur physikalische Chemie, StochiometrieZeitschrift iur deli physikalischen und ChemischenHol'pe-Sevler's Zeitsc*hift fur physiologische Chemie.Zeitschrift fiir wissenschaftliche Photographie, Photo-stoffwesen.urid Verwandtsch:tftslehre.Unterricht.l'hysik und Photochemie

ISSN:0365-6217    

DOI:10.1039/AR92219FP001

出版商:RSC    

年代:1922

数据来源: RSC

摘要:

INORGANIC CHEMISTRY.THE study of radioactivity, isotopy, and atomic constitution hasassumed such importance that a separate Report is now devoted tothese developments of inorganic chemistry, and atomic constitutionis here discussed solely from the stand-point of valency and theordinary chemistry of the elements. Nevertheless, the bulk oforthodox inorganic chemical work, including as such those cases inwhich the application of physical methods is of interest for theresults attained rather than for the methods employed, is so greatthat the Report can only be kept within thr: prescribed limits byruthless economy of words and omission of much interesting material.An effort has been made, however, to report precisely, rather thanto comment on, as much as possible of the work deemed to be ofgeneral interest to chemists.Atomic Theory.Langmuir has deduced the types of valency, and its numericalvalues, for most elements by a method simpler than that formerlyemployed,l and, on the basis of the electron theory of chemistry,Sir J.J. Thomson has attributed structures to the unit cells ofelements according to their valency, and has calculated therefromvalues for bulk-modulus, critical frequency, and dielectric constantwhich agree with experimental values. It has been founds thatcarbon dioxide and nitrous oxide have identical viscosities over therange 0-loo", and it is inferred that their molecular dimensions arethe same, in agreement with Langmuir's view that both moleculeshave the same arrangement of the outer electrons.The principle of induced alternate polarity of atoms, previouslyapplied to explain many properties of organic compounds, has nowbeen derived simultaneously and independently by Lapworth 4 andby Kermack and R~binson,~ as a necessary consequence of theelectron theory.It is perhaps important to observe that in both1 I. Langmuir, Science, 1921, 54, 59 ; A., ii, 137.2 Sir J. J. Thomson, Phil. Mag., 1922, [vi], 43, 721; A., ii, 355.8 C. J. Smith, Proc. Physical SOC., 1922, 34, 155; A., ii, 549.A. Lapworth, T., 1922,121, 416.W. 0. Kermack asd R. Robinson, ibid., 427.3INORUANIC CHEBTISTRY. 31cwe8 it is found desirable to postulate union of atoms, not only bythe normal " single " or " double '' bond, consisting in the sharingby adjacent atoms of two or four electrons, respectively, but alsoby the sharing of one or three electrons.A bond of three electronshas already been proposed aa affording the most rational expressionof the constitution of benzene, and a, single electron bond has beensupposed probable,a so that there is no special difficulty in acceptingthe variation of the Lewis-Langmuir hypothesis. Thus among theelements of the First Period this theory continues to prove adequate.Difficulties begin with sodium and increase among the heavierelements, where it becomes evident that the usual hypothesis isa t best no more than a first approximation to the truth about atomicconstitution, accounting well enough for the broad similaritieswithin and differences between the various groups, but failing togive, for example, as any hypothesis pretending to finality mustgive, it theoretical basis for the detailed differences observed withineach group.Reviewing such differences, one cannot escape theconclusion that chemical properties are determined, not by the outerelectrons alone, but by the atomic constitution as a whole; and ifthis is so, the assumption, now general, that the chemical propertiesof isotopes are identical, whilst probably true or very nearly truefor the heavier elements, may not hold for the lighter elements.It is thus important to consider the several attempts which havebeen made to amend the original hypothesis.From a consideration of emission spectra, Bohr has developed adynamic theory of the structure of the heavier elements, postulatingeccentrio orbits for certain electrons (which thus belong, in a sense,to more than one level in the atom), and irreconcilable with anyconception of sharply separated shells of electrons,' which accountsfor the colour (in compounds), paramagnetism, and relative com-plexity of spectra of the elements and is strongly supported by recentwork upon the X-ray spectra.8 Measurements of the intensity ofreflection of X-rays per unit volume of the units constitutingcrystalline sodium chloride9 may be interpreted as showing theexistence in successive shells, counting outwardly, of 7 and 3electrons in the sodium atom, and of 10, 5, and 3 electrons in thechlorine atom; or, alternatively, give for the variation of electrondensity with distance from the centre of each atom values whichagree well with those calculated for an atom of the type proposed byN.Bohr, 2;. Phy8ik, 1922, 9, 1; Nature, 1921, 108, 208; A., C, 363,6 Sir J. J. Thomson, Phil. Mag., 1921, [vi], 41, 538; A., ii, 279.277.8 D. Coster, Phil. Mag., 1922, [Vi], 43, 1070; 44. 546; A., ii, 491, 677. * W. L. Bragg, R. W. James, and C. H. Bosmquet, ibid., 1922, 44, 433;A., ii, 70332 ~ N U A L REPORTS ON THE PROGRESS OF CHEMISTRY.Bohr ; but appear to show clearly that there is not in either atom ofsodium chloride a shell of eight electrons.From the chemical point of view come attempts to bring thestatic hypothesis into closer accord with the facts by modifyingLangmuir’s fourth postulate.Bury’s modification 10 reads : “ Themaximum number of electrons in each shell or layer is proportionalto the area of its surface; thus successive layers can contain 2, 8,18, and 32 electrons. Groups of 8 and 18 electrons in a layer arestable, even when that layer can contain a larger number of electrons.The maximum number of electrons in the outer layer of an atom is8 : more than 8 electrons can exist in a shell only when there isan accumulation of electrons in an outer layer. During the changeof an inner layer from a stable group of 8 to one of 18 or from 18to 32, there occurs a transition series of elements which can havemore than one structure.” This leaves unchanged the structuresassigned by Langmuir to the elements of the %st Period, but givesto all succeeding elements new structures which are in better accordwith Bragg’s atomic diameters and satisfactorily explain manychemical properties, for example, the similarities and differences inthe triplets of Group VIII and the existence and characters of therare earths.It seems significant, too, that Bury’s structures forthe inert gases are similar to those deduced by Bohr from the emissionspectra. The argument of the paper cannot be reproduced inabstract and those interested will find that the original paperrepays careful study. It has since been shown11 that Bury’sstructures afford probabilities of complexity of spectra in generalagreement with the observed numbers of lines for many elements.Another alternative disposition of electrons (2 : 8 : 18 : 32 : 18 : 8instead of Langmuir’s 2 : 8 : 8 : 18 : 18 : 32) has been suggested byDauvillier,12 as a result of investigations of the L- and K-serieslines in the X-ray spectra of a number of the heavier metals; andhe too supposes that chemical properties are in part dependent onthe internal electrons, and that inner electron shells may be incom-plete.Regarding the “ atomic radius ” as the distance from thecentre to an electron group in the valency shell, it has been shown thatthe distance between atomic centres is often less than the sum of theatomic radii : a number of causes may be adduced to explain thefact, among which the conception of bonds of more than one electronand the possibility of more than one arrangement of electrons withinthe atomic sphere13 are of interest, as they have already beenlo C.R. Bury, J . Amer. Chem. SOC., 1921, 43, 1602; A., ii, 43.l2 A. Dauvillier, J . Phya. Radium, 1922, [vi], 3, 154, 221; Cornpt. rend.,lS M. L. Huggins, Physical Rev., 1922, 19, 346; A,, ii, 634.H. S. King, ibid., 1922, 44, 323; A., ii, 277.1921,173, 1077; A., ii, 559, 678, 43INORGIANIU €B€EMIS!CRY. 33supposed, on quite other grounds, to be possible. The suggestionis made that, in the second and third shells, the Uth and subsequentelectrons pair with the first four to give a tetrahedral arrangement ofpairs, and that the forces causing pairing result, in the case of theheavier elements, in the formation of triplets of electrons in theinner ~hells.1~This stimulating clash of theories evidently arises in part becausechemical phenomena can best be interpreted by a static conceptionof the atom whilst physical evidence demands a dynamic conception.Therefore special interest attaches to the suggestion made by SirOliver Lodge 15 that these views might be reconciled were chemicalunion attributed, not to electrical attraction between the atoms, butto interlacing of the stationary magnetic fields which must accom-pany rapidly revolving electrons.Theories of magnetism clearlytend to assume a form favourable to such an hypothesis;16 and tothe connexion between chemical constitution and magnetic propertiesin compounds, developed chiefly by Pascal (whose recent workconfirms the usual view of the constitution of the acids of sulphur,phosphorus, and arsenic),17 is given new significance by experimentsshowing that ferro-magnetism is increased in iron and actuallyimparted to manganese by fusion in hydrogen, whilst the magneticsusceptibility of palladium is reduced by the adsorption of hydrogen.These phenomena may be explained by the assumption that theentry of hydrogen into the electron system of the metal produces anew system corresponding with the element of next higher atomicnumber, in the cme of manganese, iron; in that of palladium,ailver .18Atomic Weigh.G2ucinum.-Basic glucinum acetate, prepared from the technicalcarbonate, was recrystallised from glacial acetic acid until free fromiron, sublimed, and converted into nitrate, which was dissolved inammonium carbonate.Glucinum carbonate precipitated from thissolution was calcined to oxide, and this, by ignition with carbon ina current of chlorine, gave the pure chloride, which was collectedand weighed with exclusion of water, The ratios GlCI, : 2Ag and14 M. L. Huggins, Sciewe, 1922, 55, 459; J. Arnar. Ghem. &c., 1922, 44,1 5 Sir 0. Lodge, Nature, 1922, 110, 341 ; see also W. Hughes, &id., 1922,16 For a useful summary, see A. E. Oxley, Nature, 1923, 111, 54.1 7 P. Pawl, Compt. rend., 1921,173, 713; 1922,174, 457,-1688; A., 1921,18 A. E. Osley, Proc. Roy. Soc., 1922, [A], 101, 264; A., ii,.469.BEP.-VOL. XIX.1841 ; A., ii, 632, 744.110, 37; A., ii, 701, 632.ii, 692; 1922, ii, 285, 56434 ANNUAL REPORTS ON THE PROURESS OF CHEMISTRY.GlCl, : 2AgC1 were determined in the usual manner, the mean resultof all analyses being the value GI = 9.018,19 appreciably lower thanthe accepted value Gl = 9-1.Boron.-By the methods used in the foregoing determination,the same authors 2o have measured the ratios BCl, : 3Ag andBCl, : 3AgC1, three samples of purified boron trichloride giving themean values B = 10.840, 10.818, and 10.825, respectively.Thefirst value is rejected for discordance and the rounded mean of thelatter two values, B = 10.82, is taken.Baxter and Scott 21 reduced boric oxide with excess of magnesium,extracted with hydrochloric or hydrobromic acid, and treated theresulting boron at 700" with chlorine or with argon saturated wit'hbromine vapour.The samples of chloride or bromide thus preparedwere freed from excess of halogen and repeatedly distilled throughHempel fractionating columns in evacuated glass apparatus. Eachthen gave, when compared with silver in the usual way, the valueB = 10433 & 0.01. These results, differing by no more than 1 partin a thousand, are a great improvement on those formerly available,and accord much better with the isotope ratio determined by Astonthan, for example, the value B = 10.900 found by Smith and vanHaagen ,22Yttrium-Yttria, prepared from Norwegian gadolinite andpurified by a rigorous and prolonged process of fractional crystallis-ation (as bromate) and fractional precipitation, converted intochloride and titrated with weighed silver in the usual way gave,as the mean of twenty-one values varying from 88.97 to 89.08, thevalue Yt = 89.03.23Lanthnum.-The low value, La = 138.91, found by Baxter,Tani, and Cha~in,~* has been confirmed by determination of theratio LaCI, : 3Ag using spectroscopically pure lanthanum chloride.Ten experiments gave for the atomic weight extreme values of138.84 and 138.97, with a, mean La = 1 3 8 ~ 8 9 .~ ~ It seems clear,therefore, that the international figure, La = 139.0, is too high.Some work has been recorded on measurement of atomic weights1s 0. Honigschmid and L. Birckenbach, Bcr., 1922, 55, [B], 4 ;26 Anal. 3%. Quim., 1922, 20, 167; A., ii, 641.zi G. P. Baxfer and A. F. Scott, Science, 1921, 54, 524; A . , ii, 285.22 E.F. Smith and W. K. van Hwgen, Curnegie Inst. Pub., 1918,267, 1 ;23 H. C. Fogg and C. James, J . Amer. Chem. SOC., 1922, 44, 307; L4.,G. P. Baxter, M. Tani, and H. C. Chapin, ibid., 1921, 43,lOSO; A . , 1921,&4., ii,2 14.A., 1920, ii, 247.ii, 297.ii, 454.e b B. S . Hop- and F. H. Driggs, ibid., 1922, 44, 1927; A. ii, 770INORGANIC CHEMISTRY. 35by physical methods. Forty-five determinations gave a meanvalue of 1.42897 -J= 0.00007 grams for the weight of the litre ofoxygen at 0" and 760 mm. in latitude 45", in close agreement withother recent work on this constant but less by 0-00008 gram thanthe accepted value.26 Recalculation from the known density ofhydrogen bromide, using the new value for oxygen, gives Br =79.927.37'De t crminstions of t h e normal cleiisity and compressibility ofcarboii dioxide and ethylene 28 give values for the atomic weightof carbon, 114398 and 12.000, respectively, appreciably lower thanhhe international value, C = 12-05, but in better accord withatomic theory ; and the gravimetric determinations of Richardsand Hoover have been criti~ised.~~ On the other hand, a strongprotest has been entered30 against such use of atomic weightsderived from gas densities in criticism of " chemical " atomic weights,and supported by proof 31 that the proportion of impurities inatomic weight silver and iodine is very much smaller than has beenalleged.32Chemical Reaction.Before proceeding to deal with individual elements in Grouporder, consideration must be given to certain results which cannotbe placed in any definite category (unless we invoke the hard-pressedword ca.talysis) and yet are clearly of fundamental significance.Baker has extended the experiments previously reported.=Pure liquids were sealed up in Jena-glass flasks with pure phosphoricoxide and after lapse of time were opened to atmospheric pressurethrough dry mercury and gradually heated, precaution beingtaken to avoid superheating : the temperature of steady ebullitionwas taken as the boiling point with the results given in thetable : 342o E.Moles, J. Chini. physique, 1921, 19, 100; E. Moles and I?. OonzAlez,,4naZ. 3'4.9. Quim., 1922, 20, 72; E. Moles and hl. Crespi, ibid., 190; A., ii,141, 497, 636.2 7 E. Moles, J. C'hint.physique, 1921, 19, 135; -4., ii, 140.2 8 Ph. A. Guye and T. Batuecas, Helv. Chim. Ada, 1932, 5, 532 ; T. Batue-29 E. Males, A&. 34s. Quim., 1921, 19, 255; A., ii, 51.30 G. P. Baxter, J. Amer. Chem. SOC., 1922, 44, 595; A., ii, 370.31 G. P. Baxter and L. W. Parsons, a i d . , 557; G. P. Baxter, ibid., 1922,32 P. A. Guye and F. E. E. Germ-, Compt. rend., 1914,169, 225; A.,33 H. B. Baker and Bluriel Baker, T., 1912, 101, 2339.34 H. B. Baker, ibid., 1922, In, 6GS.cas, ibid., 544; A., ii, 617, 618.44, 501 ; A., ii, 376, 377.1914, ii, 727.c 36 ANNUAL REPORTS ON THE PROGRBSS OF OHEMISTRY.Bromine ..................Mercury ..................Hexane ..................Benzene ..................tetrachloride.. .EiGyl ether ............Methyl alcohol .........Ethyl alcohol .........Carbon disulphide ...Propyl alcohol .........Period of(years).89drying84841 4 2 799999Originalboilingpoint.63"35868.48049.578356678.595Newboiling118"420-4258210680112+83120 +138134point.Rise inboilingpoint.55"621426303448546039These large differences of boiling point are undoubtedly real.Thcmercury maintained at 360" for thirty minutes did not boil and gaveonly a trace of condensate above the liquid: the hexane wastransferred to another flask, not specially dried, and still boileda t 81": water could be boiled through the benzene with onlyslow evaporation of the latter : and the ether at 20" had a vapourpressure of 374 mm.only, as against the normal value of 442 mm.The liquids recover their normal boiling points on exposure, evento air dried with sulphuric acid and phosphoric oxide; benzeneslowly, ethyl ether and the three alcohols very rapidly.Comparative experiments with dried and undried broininc,benzene, hexane, and nitrogen tetroxide showed that the capillaryrise increased steadily during drying to a value which indicatesan increase of molecular weight to 1.5-3.0 times that for the normalliquids. These results clearly support the earlier hypothesis thatdrying shifts the equilibrium between normal and associated mole-cules; possibly because absence of water hinders or inhibits dis-sociation, as it is known to do in the case of certain vapours, and hasno effect or a smaller effect on the opposing association.If, asis usually supposed, the degree of association of a liquid is increasedby lowering of temperature, information as to whether associationis stopped or merely hindered might be obtained by ascertainingthe ultimate effect of drying different specimens of the same liquidmaintained a t widely different temperatures throughout the wholeperiod of drying. It has been shown, rather unexpectedly, that inbenzene, carbon tetrachloride, carbon disulphide, ether, bromine,sulphur dioxide, and nitrogen trioxide, drying produces no changein volume as great as 1 part in 10,000.Thermometers suspended in the vapour from dry hexane andbenzene, boiling at 82" and 106", respectively, showed temperaturesof 68.4" and 80", the boiling points of the normal liquids; a verycurious result.Smits had previously suggested 35 that, supposinginternal change to be inhibited by drying, fractional distillationa5 A. Smits, 2. phy8;kd. Chern., 1922, 100, 477; A., ii, 358INORQANJ[(I CHEMISTRY. 37should result in a separation of the normal and associated liquids,and later experiments 36 have shown that if a specimen of driedbenzene is distilled over completely, the temperature of a ther-mometer suspended in the vapour shows a steady rise, indicatingthat fractional distillation does, in fact, occur.Apparently, similar changes may take place in the solid state,preliminary experiments having shown that the melting points ofsulphur and iodine, originally 112-5" and 114", are, after nineyears' drying, 117.5" and 116", respectively.It has been found 37 that the reactivity of ammonia, measured bythe expansion at constant temperature resulting from its partialdissociation in cont8act with an activated platinum wire heated by adefinite current for a definite time, is the same for ammonia obtainedby slow escape from a commercial cylinder of liquid ammonia, byheating aqueous ammonia and drying the gas with quicklime, or byliquefying either preparation and allowing it to evaporate isothermallyat its boiling point.Under the same conditions, ammonia allowedto escape very rapidly from a cylinder had a much lower reactivity,and it is concluded that an " inactive " phase of ammonia has thusbeen obtained which contains more molecules of the type character-istic of liquid ammonia 38 than are normally present in the " active "phase, and that the existence of such active and inactive phasesexplains the chemical inactivity of dried gases and supports theradiation theory of chemical r e a c t i ~ i t y .~ ~It may be suggested, however, that the experimental resultswill bear a simpler, if less significant, interpretation. It is knownthat ordinary commercial ammonia, dried over lime, containsabout 1 per cent. of water,40 and that rapid, irreversible distillationsuch as may occur by free discharge of gas from a cylinder of liquidis a very effective means of separating the constituents even of aconstant-boiling so that the gas thus obtained may wellbe considerably drier than that in real equilibrium with the cylinderliquid.Baly has found that addition of water vapour to ordinaryammonia increases its reactivity, drying certainly decreases itsreactivity, and so the greater dryness of the " inactive " form wouldappear to be capable of explaining the whole of the observations,including the " recovery " of the gas in cylinders on standing (by38 H. B. Baker, private communication.37 E. C. C. Baly and H. M. Duncan, T., 1922, 121, 1008.38 The "liquidogen " molecules of Traube, Ann. Phyaysill., 1902, [iv], 8,39 E. C. C. Baly, Phil. Mag., 1920, [vi], 40, 15; Trans. Paraclay SOC.,4o See, e.g., A. G. White, T., 1922, 121, 1688.41 See, e.y., R. S. Mulliken, J .Amer. Ohem. SOC., 1922, 44, 2389; A . , 1923,1922, 17, 588; A., ii, 628,ii, 3138 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.acquisition of the equilibrium content of water vapour), identityof slowly released cylinder gas with laboratory preparations driedby lime, recovery of “ inactive ” gas in the experimental tube whenthe wire is heated at 200” (release of adsorbed water from the wireor walls), and t,he increase in reactivit,y of “ inactive ” ammoniawith increase of temperature of the wire (the five pairs of figuresgiven show that twenty seconds’ heating with currents of 4.00,4.10,4*25,4*35, and 4.50 amps. produces decomposition in the ratiosactive/inactive = 2.18, 1.76, 1-60, 1.46, and 1-35, respectively).The “activation” of chlorine by light, a subject of much pastcontroversy, has been reaffirmed.A rigid series of experiments 42proves that when chlorine is exposed to sunlight or intense ultra-violet light and mixed with hydrogen in the dark, reaction occursimmediately on exposure of the mixture to the light of two 100-watt tungsten lamps, whilst with chlorine not so insolated reactionis delayed by the known “ induction period ” of about two minutes.The effect of insolation persists in the dark for three hours, but isdiminished after twenty-four hours and disappears after severaldays. A n equally rigorous series of experiments shows that chlorineexposed to the light of a 3000-watt Bovie quartz mercury lamp orto a high tension discharge will not react with hydrogen in the darkeven when the interval between insolation and mixing is only 0.01second, so that any explanation of activation in terms of the forma-tion of a triatomic or other active form of chlorine seems improbable.A globule of fused calcium chloride between two copperwires shows great decrease in resistance in presence of a trace ofmoisture, and use of this device as a “ detector ” has shown thatpure hydrogen reacts with copper oxide at a definite and reproducibletemperature, which is lowered some 20” if the hydrogen first passesover platinised asbestos.Similar results were, obtained with hydro-gen and sulphur, formation of hydrogen sulphide (detected by leadacetate paper) occurring a t a lower temperature if the hydrogenfirst passed over palladium black.The activated hydrogen wasfound to be ionised, but only to an extent considered altogetherinsufficient to explain reaction; and the persistence of the pheno-menon when glass wool was interposed between the platinisedasbestos and copper oxide and the absence of any change in refractiveindex by activation or increase of volume on decay seem to showthat the observed effects cannot be attributed to monatomic ortriatomic hydrogen. The explanation advanced is that the internal42 G. L. Wendt, R. S. Landauer, and W. W. Ewing, J. Amer. Chem. SOC.,4s P. Anderson, T., 1922, 121, 1153; see also, R. N. Pease and H. S.1922, 44, 2377; A., 1923, ii, 22.Taylor, J . Amer. Chem. SOC., 1921, 43, 2179; A., ii, 148INORGANIC CHEMISTRY. 39energy of the hydrogen molecules is increased by contact with theplatinum or palladium : this should result, presumably, in a loweringof the temperature of the metal, and the explanation might thus betested experimentally.Lastly, reference may be made to the mysterious variationobserved 44 in the rate of decomposition of mercuric fulminate in avacuum a t 80", which seems to bear some resemblance to theforegoing unexplained phenomena.The Inert Gma.A spectrophotometric method has been developed for the estim-ation of krypton and xenon in admixtures with argon.45 Positive-ray analysis of the residues from a thousand tons of liquid air hasgiven evidence of new constituents of the atmosphere with molecularweights 163 and 260 ; but the observead lines may be due to diatomicmolecules of xenon and krypton.4GPrecise determinations show that the solubility of helium has not,as was supposed, a minimum a t 20°.*' A detailed account of thedistribution, sources, and chemical composition of helium-bearingnatural gases has been published.PsAnderson has shown 49 that in the explosion of metallic wiresby heavy condenser discharges a temperature of some 20,000' isattained in the wire in 1/300,000 second.It is now reported thatthin tungsten wires exploded in this way yield gas which whenobtained in a vacuum shows the helium spectrum, and if obtainedin an atmosphere of pure carbon dioxide and measured afterabsorption of the latter in alkali has, as the mean of twenty-oneexperiments, a volume which corresponds t Q an amount of heliumabout 25 per cent.of the weight of tungsten taken.60 This result,if confirmed, would appear to be the first case of atomic decompositionby artificial means.Group I .Active hydrogen51 has been prepared in the Siemens ozoniser,using both induction coil discharge and a Tesla discharge of muchhigher frequency and voltage, and also by passing pure hydrogen44 R. C. Farmer, T., 1922, 121, 174.45 C. Moureu and A. Lepape, Compt. rend., 1922, 174, 908; A., ii, 394.46 Sir J. J. Thomson, Proc. Roy. SOC., 1922, [A], 101, 290; A., ii, 565.47 H. P. Cady, H. M. Elsey, and E. V. Berger, J . Amer. Chem. SOC., 1922,4 8 G. S. Rogers, U.S. Qeo2. Survey, Prof. Paper, 1921, No. 121.49 J. A. Anderson, Astrophys. J . , 1920, 51, 37.6o G.L. Wendt and C. E. Irion, J. Amer. Ch.em. SOC., 1922, 44, 1887;51 Ann. Report8, 1920, 17, 31.44, 1456; A., ii, 642.A., ii, 77340 ANNUAL REPORTS ON TBE PROGRESS OF CFIEMIS!L'RY.over a platinum wire heated electrically at 800°, the effect in thiscase being probably due to the emission of positive ions. It isdecomposed by contact with certain metals (Pt, Ni, Cu, Pb, Sb, Cd)and unchanged by others (Ag, Hg, Sn, Bi, Mo, Zn, Al). Definiteproof was obtained that hydrogen contracts when activated andrecovers its original volume on standing, and that the active formcondenses to a liquid a t or slightly above -180". A relatively slowprogressive change is observed in the spectrum produced by thedischarge during the activation a t -180",62 the Balmer series givingway to the secondary line spectrum.These results, especiallythe evident smallness of the energy change involved in its tlierm-ionic production, support the original view that this active hydrogenis in fact triatomic hydrogen, H, (named hyzone, by analogy withozone), rather than the isotope of hydrogen, isohydrogen, of atomicweight 3 (containing a single atomic nucleus of three protons)postulated by Harkins as a unit of atomic structure and, ratherunfortunately, symbolised by him as H,.Wood has observed s3 that long vacuum tubes containing hydrogengive, in the central portion, mainly the Balmer series spectrum anda t the ends mainly the secondary spectrum. On closing the switch,a momentary flash of the secondary spectrum, lasting about 1 /50 sec.,is seen throughout the tube, provided that 1/5 sec. or more haselapsed since the previous discharge.With dry hydrogen, noBalmer series is seen unless a momentary heavy condenser dischargeis passed. Gas drawn by a pump from the central portion of thetube and caused to impinge upon fractured glass surfaces (or somemetals, oxides, and other substances), raises them to incandescence."The explanation advanced is that molecular hydrogen (to whichthe secondary spectrum is attributed) is dissociated by the dischargeto form atomic hydrogen (believed to be the source of the Balmerspectrum), the incandesence of solids being due to their acting ascatalysts for the exothermic recombination of the atoms.Clearly the phenomena observed by Wendt and by Wood arevery intimately related, but further experiment is necessary todecide finally which interpretation is correct, although Wendt'sseems more probable.There is a concurrence of opinion that the" clean-up " of hydrogen and nitrogen in discharge tubes is due tochemical changes.56 Evidence has been obtained that active62 G. L. Wendt and R. S. Landauer, J . Amer. Chem. SOC., 1922, 44, 510;63 R. W. Wood, Phil. Mag., 1921, [vi], 42, 729; A., 1921, ii, 665.O4 R. W. Wood, Proc. Roy. floe., 1922, [ A ] , 102, 1; A., ii, 759.A . , ii, 369.F. H. Newman, Phil. Mag., 1922, [vi], 44, 215; Nature, 1922, 109,749; G. L. Wendt, ibid., 749; A., ii, 546, 639, 639INORGIANIC CHEMISTRY. 41modifications of hydrogen and nitrogen are produced also by theaction of a-rays.mMeasurement of the dissociation tensions has shown that lithiumhydride is the most stable of all the alkali and alkaline-earth hydrides,those of calcium, strontium, and barium decreasing in stability inthe order named.s7 X-Ray photographs of lithium hydride show astructure similar to that of sodium chloride, with positive lithium-ions and negative hydrogen-ions,m and the view that metallichydrides are true salts, in which hydrogen acts as a halogen, isvindicated also by very ingenious and skilful experiments provingthat electrolysis of a solution of calcium hydride in a fused eutecticmixture of potassium and lithium chlorides gives hydrogen a t theanode in the quantity required by Faraday's law.6OPure hydrogen peroxide is diamagnetic to a greater extent thanwater and therefore does not appear to contain the molecularlinking characteristic of molecular oxygen : its solubility in alcoholis 18 per cent.and in ether 1 per cent. ; it is insoluble in pure drybenzene. Curves of solubility for sodium chloride, sodium nitrate,and sugar in hydrogen peroxide are generally similar to those for thesame substances in water and indicate a similar degree of ionisationof the salts. The curve for sodium sulphate in hydrogen peroxidediffers materially from that in water, owing to the formation of thecompound Na2SOp,2H20,. The halogen hydrides are apparentlyinsoluble in the peroxide, but are oxidised thereby ; and the halogensare much less soluble than in water.Investigation of the freezing-point curve for the system NH3-H20, up to a concentration of60 per cent. of ammonia shows the existence of one compound only,NH,,H202, m. p. 24.5", which can be prepared also by the action ofammonia on the peroxide in anhydrous ether. Hydrogen peroxideis quite stable in the absence of water, but its decomposition is,of course, autocatalytic.60Lithium nitrate, with a little water, is a good absorbent forammonia, and the resulting liquid, unlike those produced withammonium nitrate or thiocyanate, has no corrosive action on steelor iron .61Fused caustic soda contains about 1-1 per cent. of water, whichcan only be removed by heating a t 500" in a vacuum. The action66 F. H. Newman, Phil. Mag., 1922, [vi], 43, 455; A., ii, 279.6 7 F.Ephraim and E. Michel, Helw. Chim. Acta, 1921, 4, 900; A., ii, 58.J. M. Bijvoet and A. Krarsaen, Proc. K . A M . Wetensch. Amterdam,1922, 25, 26; A., ii, 569.69 D. C . Bardwell, J . Amer. Chhem. Soc., 1922, 44, 2499; A., 1923, ii, 20.6o 0. Maass and W. H. Hatcher, aid., 2472; A., 1923, ii, 21.R. 0. E. Davis, L. B. Olmsterad, and F. 0. Landstrum, ibid., 1921, 43,1575, 1580; A., ii, 66, 49.U 42 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.upon iron, nickel, and copper of fused caustic soda, with and withoutthe addition of 5-10 per cent. of sodium peroxide, has been studiedat 350-720"; the results are very complex and interesting, manydefinite crystalline products having been obtained. That obtainedfrom iron forms transparent red hexagonal crystals, stable toboiling water or aquedus caustic soda and to cold dilute mineralacids, but apparently decomposing when kept ; analysis gave thecomposition Na2Fes06, and there is some evidence that a similarcompound is formed with nickel.62Sodium sulphate tetrahydrate, Na,S04,4H,0, otherwise unknown ,has been shown to exist in mixed crystals with sodium chromate.63Experience gained in the preparation of free tetraethylammoniurnhas led to the preparation of free ammonium in about a 50 per cent.yield by the addition ,of a 1.8 per cent. solution of potassium inliquid ammonia to a 1 per cent.ammonia solution of ammoniumchloride at -70°.64Rubidium bromate, prepared from the pure carbonate and bromicacid and recrystallised, forms, like caesium bromate, small hexagonaJcrystals resembling cubes, m.p. 430°, and sparingly soluble in1vater.~5Measurement over a range of temperatures of the dissociationpressures of hydrated cupric alkali sulphates, of the type CuSO,,Mx2S0,,6H,0, showed the stability a t any given temperature toincrease in the order K, Rb, T1, NH,, Cs; and it is inferred that thebasicity of the corresponding hydroxides increases in the sameorder.66Excess of hydrogen peroxide gives with cold solutions of sodiumcopper carbonate a gelatinous, yellowish-brown precipitate havingan oxygen : copper ratio between Cu : l+O and Cu : 20, thus afford-ing fresh evidence for the existence of an unstable peroxide, C U O ~ . ~ ~The action of potassium persulphate on cuprous hydroxide in presenceof barium hydroxide below 0" is said to give the oxide Cu,O, which,whilst an oxidising agent, is apparently not peroxidic.68Cuprous sulphide is formed by the action of sulphur on cuprous~hloride.~O Cupric sulphide on oxidation by air yields free sulphur62 T.Wallace and A. Fleck, T., 1921, 119, 1830.63 T. W. Richards and W. B. Meldrum, J . Amer. Chem. Soc., 1921, 43,64 H. H. Schlubach and F. Ballauf, Ber., 1921, 54, [BJ, 2825; A., ii, 55.65 H. D. Buell and C. R. McCrosky, J. Amer. Chew&. XOC., 1921, 43, 2031;66 R. M. Caven and J. Ferguson, T'., 1922, 121, 1406.67 J. Aldridge and M. P. Applebey, ibid., 238.68 G. Scagliarini and G. Torelli, Gazzetta, 1921, 51, ii, 225; L4., ii, 68.6s F.W. Pinkard and W. Wardlaw, T., 1922, 121, 1300.1543 ; A., ii, 54.A., ii, 146INORGANIC CHEMISTRY. 43if freshly precipitated, but only cupric sulphate and thiosulphateif preserved for some hours before exposure to oxygen; the exist-ence of two modifications, formulated as Curl:S and Cu*:S:S, isinferred. 7OThe corrosion of copper by ammonium nitrate and ammoniahas been found to yield cupric tetrammine nitrate and nitrite, andthe preparation of the latter compound from basic cupric nitriteand ammonia is described. Dry cupric tetrammine nitrate isremarkably stable, retaining its ammonia a t 120" in a vacuum, butexploding a t 212" : the nitrite loses ammonia a t 95-100" in air,forming the diammine nitrite, CU(NH,),(NO,),.~~A strong solution of sodium persulphate (preferable to thepotassium salt because of its greater solubility) acts on finelydivided crystalline silver or concentrated aqueous silver nitrateto give a black peroxide which, in the latter case, gave an atomicratio O/Ag as high as 1.295 and therefore was possibly impurc~g,0,.72In sharp contrast with a number of doubtful or negative r e s ~ l t ~ s , ~ ~Hartimg,-using a Steele and Grant type B quartz micro-balance 74carrying 43 mg.and sensitive to 2 x 10-5 mg., has shown that filmsof silver chloride, bromide, or iodide, formed by direct halogenationof silver films, deposited from a tartrate silvering solution on thinsilica supports, arc darkened on exposure to light and lose weight,in some experinicnix with the chloride to the extent of more thanSO per cent'.of thc halogen present in the salt. Decomposition wasaccelerated in a vacuum or by presence of ozone, and rehalogenationrestorcd the original weight and colo~r.~5 It seems clear, therefore,that neither oxygen nor water is essential to light action on the silverhalides, and that tlheir decomposition yiclds metal and halogen, andnot a sub-halide.Adsorption of iodine from aqueous or alcoholic solution does notoccur with pure silver iodide,76 and Carey Lea's observation to thecontrary was probably due to the presence of silver nitrate as an5" W. Gluud, Bw., 1922, 55, [B], 952, 1760; A . , ii, 448, 572.71 H. Bassott and R. G. Durraiit, T., 1922, 121, 2630.72 G. I. Higson, ibid., 1921, 119, 2048.'3 A.G. Rabinovich. J. Physical Chem., 1922, 26, 577; C. Tubandt aridG. Eschenhagen, 2. physikal. Cltem., 1922, 100, 489; J. Eggert and W.Noddack, Sitzungsber. Preuss. Akad. Wiss. Berlin, 1921, 631 ; F. Weigertand W. Scholler, ibid., 1921, 641; P. P. Koch and F. Schrader, 2. Physik,1921, 6, 127; A., ii, 605, 346, 9, 10, 153.74 E. J. Hartung, Phil. Mag., 1922, [vi], 43, 1035; A . , ii, 495.7 5 Idem., T., 2922, 121, 682.76 F. E. E. Germann arid R. N. Trader, J. Amar. Ghem. SOC., 1922, 44,460; A., ii, 371.c* 44 ANNUAL REPORTS ON THE PROQRESS OF CHEMl'STRY.impurity in his silver iodide. Silver perchlorate is extremely solublein water and moderately soluble in benzene, and the three com-ponents form a remarkable system which has been studied up to themelting point of silver nitrate; silver perchlorate and water havethe lowest eutectic point known for a true salt and water, - 50.2" ;and a hydrate, AgClO,,H,O, and a compound, AgClO,,C&6, havebeen isolated.77 Silver bromate is dimorphous, forming tetragonalcrystals below and hair-like crystals above the transition point,986"; the dry salt melts at 308-310" and is stable to light; itmay advantageously be substituted for arsenious oxide as a standardin i0domet1-y.~~ The existence of colourless and yellow forms ofalkali silver thiosulphates is confirmed, and several new compoundsof this type are described.79A number of new, complex gold chlorides containing ammonium,rubidium, and caesium have also been prepared.80 Anodic oxidationof gold in dilute sulphuric acid is shown to yield auric hydroxide.*lHydrogen sulphide in excess reacts with very dilute aqueous chloro-auric acid to give pure auric sulphide, but the sulphides Au,S andAu,X, could not be obtained.82The existence of reaction limits in gold alloys previously reported 83has been confimed by electrochemical in~estigations,8~ and Tam-mann's explanation, although subject to criticism, still appearsthe most probable.85Group I I .A comparison of the band spectrum of glucinum with that ofaluminium confirms the close similarity of atomic structure forthese metals which would be anticipated from their chemicalrelations hip .86Glucinum hydroxide precipitated from the sulphate by ammoniais found always to contain much ammonium sulphate, which cannot77 A.E. Hill, J . Amer. Chem. SOC., 1922, 44, 1163; A., ii, 555.78 J. H. Reedy, ibid., 1921, 43, 1440; A., ii, 56.79 E. Jonsson, Ber., 1921, 54, [B], 2556; A., ii, 57.80 E. Susclinig, Monatsh., 1921, 42, 399; A,, ii, 514; H. L. Wells, Amer.J . Sci., 1922, 3, [v], 257, 315, 414; A., ii, 449, 449, 514.F. Jirsa and 0. Buryhek, Chem. Listy, 1922, 16, 189; A., ii, 713.a2 A. Gutbier and E. Diirrwachter, 2. amrg. Chem., 1922, 121, 266; A.,83 Ann. Reports, 1919, 16, 198.84 G. Tammann, 2. anorg. Chem., 1921, 118, 48, 93; 1922, 121, 193;R. Lorehz, W. Fraenkel, and M. Wormser, ibid., 1921, 118, 231; A., ii, 75,380, 63, 21.85 G. Masing, 2. anorg. Chem., 1921, 118, 293; W. H. Creutzfeldt, ibid.,1922,121, 25; W.Jenge, ibid., 1921,118, 36; G. Tammann, 2. Elektrochem.,1922, 28, 36; A., ii, 37, 347, 64, 255.ii, 513.86 L. C. Glaser, Ann. PhysiE, 1922, [iv], 68, 73; A., ii, 675INORGANIC CHEM'ISTRY. 45be washed out unless the hydroxide is first dried and powdered;when thus purified and dried, i t approximates closely to thecomposition G1( OH),.The form of the 25O-isotherm for the system G;1S0,-(NH4),S04-H,O shows that over the range 27-30 per cent. of GISO, and 25-37per cent. of (NH,),S04, the solid phase is the double salt, GISO,,(NH4),S0,,2H,O ; 87 and solubility determinations for glucinumsulphate in water indicate that GIS04,4H,0 is the only solid phase,and that the hexahydrate previously reported is not formed.88Dilute magnesium amalgam absorbs ammonia with separationof a solid solution of magnesium hexammoniate, Mg(NH,),, inmercury ; 89 and thermal analysis of the system magnesium-mercuryshows the existence of the compounds MgHg,, with transition at170" to MgKg, m.p. 625"; Mg,Hg,, m. p. 562"; and Mg,Hg, m. p.580".99Magnesium perchlorate has been found to form a trihydrate aswell as the hexahydrate previously described: it is completelydehydrated without decomposition at 250", and the anhydrous salthas a remarkable avidity for water and has been proved to bean excellent neutral drying agent, rather slower in action thanphosphoric oxide but as efficient as the latter at the ordinarytemperature, capable of absorbing a greater quantity of water perunit weight, and easily regenerated by heating.91 Evidence isadduced for the existence of magnesium sulphate octahydrate,having a transition point to the heptahydrate at 48.2°.92An improved method is given for the electrolytic preparation ofdilute calcium amalgam.93 Metallic calcium gives a vapour pressurecurve which, by extrapolation, indicates a boiling point of 1240" ;but the metal used contained nearly 3 per cent.of impurity, including1.62 per cent. of magnesium,g4 and it seems appropriate to repeatthe protest entered in a previous Report against the use of impureor indefinite material in exact determinations. Pure calcium isfound to be almost passive toward nitrogen, but the presence of moreelectropositive metals (K, Ba) or, better, calcium nitride favoursreaction .958 7 H.T. S. Britton, T., 1922, 121, 2612.8 8 Idem., ibid., 1921, 119, 1967.89 A. G. Loomis, J . Amer. Chem. SOC., 1922, 44, 8; A., ii, 294.90 R. P. Beck, Rec. trav. chim., 1922, 41, 353; A., ii, 545.91 H. H. Willard and G. F. Smith, J . Amer. Chem. Soc., 1922, 44, 2255;92 S. Takegami, J . Chem. SOC. Japan, 1921,42, 441; A., 1921, ii, 698.93 B. S. Neuhausen, J . Amer. Chem. SOC., 1922, 44, 1446; A., ii, 643.94 N. B. Pilling, Physical Rev., 1921, 18, 362; A., ii, 291.s5 0. Ruff and H. Hartmcmn, 2. an0l.g. Chem., 1922, 121, 167; 0. Ruff,2. physikal. Chem., 1922, 100, 419; A., G, 377, 363.A , , ii, 86046 ANNUAL REPORTS ON THE PROGRESS OF CREMISTRY.The existence of solid calcium-ammonium at - 15" to + 30" isconfirmed; 96 and new compounds of calcium chloride with 1 mol.of ammonia and of calcium bromide and iodide with 1, 2, and 8molecules of ammonia have been prepared, and the vapour tensionr:of these and the known ammines determined97 The second calciumsilicide previously reported and variously formulated by differentworkers, is now shown to be calcium monosilicide, CaSi or Ca,Si,.98Strontium is completely insoluble in solid lead, but forms onecompound, Pb,Sr, m. p.676", which is said to form with lead aeutectic melting a t the same temperature as lead.1Reaction between nitrogen in excess and compressed mixturesof barium carbonate with wood-charcoal or graphite attains itpracticable velocity a t 1300-1400" : in fifteen to thirty minutesat this temperature, formation of cyanide reaches a maximum of65 per cent., which is not increased at 1600".The primary changeproduces barium carbide, which then reacts with nitrogen to formcyanide ; cyanamide formation is due to a secondary reaction whichis facilitated by higher temperature.2Barium sulphate dissolves in 98 per cent. sulphuric acid a t 25"to the extent of 14.9 grams/100 c.c., and the solution containsbarium sulphuric acid, H,[Ba( SO,),], which can be accumulatedand crystallised in the anode compartment by electrolytic transport.Barium selenic acid can be prepared in a similar manner or bycrystallisation from a saturated solution of barium selenate inselenic acid.3Thermal analysis shows the zinc-arsenic alloys to comprise twobrittle compounds, Zn3As2, m.p. 1015", and ZnAs,, m. p. 771";and indicates that magnesium and cadmium form one compound,CdMg, soluble in all proportions in either metaL6Cadmium dissolves in aqueous ammonium nitrate quietly andwithout evolution of gas, and it has thus been proved that impuritiesin the metal form a net-like structure between the crystallites.6for the purificationof mercury by air a t 150" showed that it removed lead completelyTests of the method previously describedS6 E. Botolfsen, Bull. SOC. chim., 1922, [iv], 31, 561; A,, ii, 570.9 7 G. F. Huttig, 8. anorg. Chem., 1922, 123, 31; A., ii, 849.98 L. Wahler and F. Miiller, ibid., 1921, 120, 49; A,, ii, 293.E. Piwowarsky, 8. Metallk., 1922, 14, 300; A . , ii, 644.2 P. Askenasy and F. Grude, 2.EEektrochem., 1922, 28, 130; A., ii, 445.a J. Meyer and W. Friedrich, 2. physikal. Chem., 1922, 101, 498; A.,4 W. Heike, 2. anorg. Chem., 1921, 118, 264 ; A., ii, 60.6 L. Guillet, Rev. Met., 1922, 19, 359; A., ii, 670.6 G. Tammann, 2. anorg. Chem., 1922, 121, 275; A., ii, 502.1 Ann, Repwts, 1921, 18, 45.ii, 644INORGANIC CHEMISTRY. 47with a loss of 2 per cent. of mercury as against a loss of 3.7 per cent.when purification was effected in the usual way with nitric acid(d 1.175), but that tin was not completely eliminated by fifteenhours' air treatment (loss 1.4 per cent.) or by three passages throughnitric acid (loss 9.2 per cent.).8 A study of the equilibrium betweenmercuric chloride, yellow mercuric oxide, and water a t 35" showsthe existence of two oxychlorides of mercury ; HgC1,,2HgO, formingpurplish-scarlet needles, and HgC1,,4HgO, a brownish-yellowamorphous substance which appears to form a solid solution withmercuric oxide.Group 111.The potassium salt of Iiexahydrodioxydiboron has been isolated.Magnesium boride is extracted with dilute aqueous potassiumhydroxide, the extract is concentrated in a vacuum, separated frompotassium metaborate and magnesium hydroxide and furtherconcentrated, and the residue is washed with methyl alcohol andrecrystallised two or three times in a vacuum from water free fromcarbon dioxide.It forms slightly deliquescent, colourless crystals,easily soluble in water. The solution has an alkaline reaction, is apowerful reducing agent, and yields hydrogen when acidified andeven, slowly, on exposure to atmospheric carbon dioxide ; concen-trated nitric acid acts upon the solid salt so vigorously that thehydrogen evolved takes fire.The salt in solution evolves 2-95 percent. of its weight of hydrogen; the residual solution can furtherabsorb 1 atom of iodine for each two atoms of hydrogen previouslyevolved ; and measurements of equivalent conductivity indicatethat the molecular formula is K,02B,H,.10 The properties of thesalt thus confirm the earlier view 11 that aqueous extracts ofmagnesium boride contain the acid H,B,O,, to which the structuralformula (I) is attributed because i t best represents the loss of hydro-gen to form (11) and the subsequent interaction with iodine (111).In the course of attempts to prepare complex polyborates, thepentaborates of potassium, rubidium, and thallium, M1,0,5B,0,,crystallising with 8,10, and 8H20, respectively, have been prepared.12Crystalline aluminium hydroxide, identical under X-ray examina-tion with the mineral gibbsite, begins to decompose only at 145" and* C.Harries and F. Evers, 2. angew. Chem., 1921,34, 541 ; A., 1921, ii, 698.S. Toda, J. Chern. SOC. Japan, 1922, 43, 312; A., ii, 769.lo R. C. Ray, T., 1922, 121, 1088.Of Travers, Ray, and Gupta.l2 A. Rosenheim and F. Leyser, 2. anorg. Chem., 1921, 119, 1 ; A., ii, 5048 AKNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.at 200' still retains 8 per cent. of water, which is completely removedonly a t much higher temperatures. The product of dehydrationa t 275" adsorbs water, but does not combine with it.Aluminaprepared by dehydration at 325" gives an X-ray pattern whichindicates a structure, crystalline, but different from that of diaspore,AI,O,,H,O, or corundum; the product of calcination above 1000"gives the pattern of corundum.13Aluminium chlorosulphoxide, AlCl,,SO,, is obtained by agitatingpowdered aluminium chloride with sulphuryl chloride for eighthours a t 0-30" with rigid exclusion of water; when treated withsulphur or sulphur monochloride in sulphuryl chloride solution,it yields a crystalline precipitate of the compound Al,cI6,S,c&.Both compounds are violently decomposed by water, in the lattercase with separation of free sulphur, and are extremely active agentsfor the chlorination of organic c0mpounds.1~It has been found that hydrochloric and sulphuric acids do not,as has been supposed, reduce thallic oxide, but dissolve it to form thecorresponding thallic salts.The existence of an acid (or mixed)sulphate, with a ratio T1: SO, = 1 : 2, has been con6irmed; andthe reduction of thallic salts by hydroxylamine, ferrous sulphate, andsodium arsenite has been found to proceed according to the equationsTl,O, + 2NH,*OH --+ T1,O + 3H,O + N,O ; Tl,(SO,), + 4FeS0, -+2Tl,SO, + 2Pe,(SOp), ; Tl,O, + As,O,--3 T1,O + As,O,.15 There isreason to believe that T12S0,,T1,(S0,), and 5Tl,SO,,TI,(SO,), arethe only thallous-thallic sulphates which exist.16Thermal analysis of the system TI,O-B,O, indicates the existenceof thallous ortho-, meta-, and pyro-borates, the first melting at370" with decomposition and the others melting at about 474" and434", respectively.17 Double halides of thallium and bismuth,2T1Br,BiBr3 and 2T11,Bi13, precipitated by potassium bromideor iodide from nitric acid solutions of the constituent metals, formrespectively lemon-yellow and red hexagonal crystals, readilyhydrolysed to thallous halide, bismuth oxyhalide, and free halogen ; 18and some double thiosulphates of thallium and arsenic, anti-mony, or bismuth, of the type T1,M(S2O,),,l9 and complex or1z. L.H. Milligan, J. Physical Chem., 1922, 26, 247; A., ii, 447.1 4 0. Silberrad, T., 1922, 121, 1015.l5 A. J. Berry, i b i d , 394.10 A. Benrath and H. Espenschied, 2.anorg. Chem., 1922, 121, 361; A.,1 7 G. Canneri and R. Morelli, Atti R. Accad. Lincei, 1922, [v], 31, i, 109;I* G. Canneri and G. Perina, Gazzetta, 1922, 52, i, 241; A., ii, 512.lo V. Cuttica and A. Paciello, ibid., 141; A,, ii, 377.ii, 504.A., ii, 571.G. Canneri, ibid., 37 ; A., ii, 378INORQANIU CHEMISTRY. 49double nitrites of thallium with copper, nickel, barium, or lead,T1,[Cu(N02),] ; T14pi(N02)6] ; T1N02,2Ba(N0,), ; 2T1N02,Pb(NO,),,HiO have been described.20A careful redetermination has been made of the densities of theoxides of six rare-earth metals (La, Pr, Nd, Sm, Eu, Gd),21 and agood deal of work, which cannot usefully be summarised here, hasbeen done on the separation of the rare-earths by basic precipitationand kindred methods,22 and on the extraction of scandium fromfhorveitite and its p~rification.~~Group I V .The fusion of carbon a t atmospheric pressure by resistance heatingof carbon rods is reported : the solidified drops of carbon and thepoints from which they are detached are said to consist of puregraphite.24 The observation that diamond is unchanged whenheated a t 1100" in carbon dioxide but becomes covered withamorphous carbon25 would, if correct, seem to afford a possiblemeans of preparing pure carbon without possibility of contaminationwith hydrogen, an attempt to obtain this by decomposition of carbonmonoxide a t 450" in presence of ferric oxide having failed.26When aqueous carbon dioxide is added to a large excess ofammonia, the anhydrous carbon dioxide immediately formsammonium carbarnate, which is sufficiently stable to permit theprecipitation of the carbonate carbon dioxide as barium carbonate.This method has been applied to a study of the hydration of carbondioxide in solutions of sodium hydroxide and sodium carbonate.27Iron pentacarbonyl is best obtained from iron and carbon monoxidea t 200" and 300 atm.pressure; molybdenum ca,rbonyl, formerlysupposed to be Mo(CO),, is now found to have a Mo : CO ratio 1 : 5.2,best represented by Mo,(CO),, or a similar complex formula. Tworuthenium carbonyls are obtained a t 300-400 atm. pressure : onea crystalline solid of unknown composition, soluble in benzene butinsoluble in alcohol or water; the other a chocolate-brown,amorphous solid, Ru(C0)2, insoluble in benzene, but soluble in21 W.Prandtl, Ber., 1922, 55, [B], 692; A,, ii, 379.22 W. Prandtl and J. Rauchenberger, 2. anorg. Chem., 1921,120, 120, 311 ;W. Prandtl and J. Losch, ibid., 1922, 122, 159; P. H. M.-P. Brinton andC . James, J . Amer. Chem. SOC., 1921, 43, 1397, 1446; A., ii, 298, 770, 769,62, 39.23 P. Urbain and G. Urbain, Compt. rend., 1922, 174, 1310; A., ii, 604.24 E. Ryschkewitsch, 2. Elektrochem., 1921, 27, 446; 1922, 28, 186;25 A. Foix, Bull. SOC. chim., 1922, [iv], 33, 678; A., 5, 641.26 J. P. Wibaut, Rec. trav. chim., 1922, 41, 400; A., ii, 665.2 7 C . Faurholt, 2. anorg. Chem., 1921, 120, 85; A., ii, 272.compare F. Sauerwald, ibid., 1922, 28, 183; A., 1921, ii, 696; 1922, ii, 44350 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.alcohol or water without decomposition.28 The action of nitric oxideon cobalt tetracarbonyl causes evolution of carbon monoxide andyields a cherry-red liquid which has been definitely characterisedas Co(CO),,NO, d1@ = 1.5126 ; m.p. - 1.05" ; b. p. 78.6" at 760 mm.Mol. wt. (from V.D.) = 171.7 (calc. M = 173); it decomposesslowly above 66". Similar actions take place with nitric oxide andnickel pentacarbonyl or diferro nonacarbonyl, but the yields weretoo small to enable the composition of the products to be e~tablished.2~Pure sugar charcoal, heated with sulphur at 400-1000" at lowpressures, yields a coke-like solid containing 2.0-3.5 per cent. ofsulphur which is not extracted by toluene and is only partly oxidisedby bromine water or removed by heating a t 750" in hydrogen : thisaffords further evidence of the existence of stable solid sulphidesof carb0n.wInvestigations of the solubility in hydrofluoric acid of the varietiesof silicon obtained by crystallisation from solution in moltenaluminium, silver, and copper lead to the conclusion that they differmainly in degree of subdivision and are not really allotropic forms ;a view confirmed by X-ray evidence that the structures of amorphous,graphitic, and crystalline silicon are identical.32Sodium metasilicate is found to yield three hydrates only:Na2Si0,,9H20, rhombic, m.p. 47" ; Na2Si0,,6H20, monoclinic,m. p. 63.5"; and Na2Si0,,4H20, hexagonal, m. p. 83-85', otherhydrates mentioned in the literature being probably mixtures ofthese.33Much interesting work has been done on germanium, our previousknowledge of which was due very largely to Winkler, whose investi-gations were limited by lack of material.Germanium has beenextracted from zinc residues containing about 0.2 per cent. of Geby processes, described in detail in the original,34 dependent on thevolatility of the chloride with steam; in this way relatively largeamounts of this very rare element have been obtained and are beingutilised in a reinvestigation of its compounds.Germanium dioxide is largely, but not wholly, reduced to metalby hydrogen at 550-900"; the metal reacts with pure bromine,28 R. L. Mond and A. E. Wallis, T., 1922, 121, 29.29 Idem., ibid., 32.3o J. P. Wibaut, Proc.K. Akad. Wetensch. Amsterdam, 1921, 24, 92; Rec.31 W. Manchot, Ber., 1921, 54, [B], 3107; W. Manchot and H. Funk,32 W. Gerlach, Physikal. Z., 1922, 23, 114; A., ii, 265.33 A. Erdenbrecher, Mikrokosmoe, 1921, 15, 55; A., ii, 444.s4 L. M. Dennis and J. Papish, J . Amei. Chem. SOC., 1921, 43, 2131 ; A . ,trav. chim., 1922, 41, 153; A., ii, 52, 373.2. anorg. Chem., 1922, 120, 277; 122, 22; A., ii, 144, 286, 764.ii, 150INORUANIC CHEMISTRY. 51superficially a t the ordinary temperature, completely a t 220°, toform the tetrabromide, which is best purified by fractional distillationand then forms a white solid crystallising in regular octahedra,in. p. 26.1", b. p. (corr.) 185-9". The liquid can be supercooled to- 18" and has nF = 1.6269, GI= 3-1315, and specific con-ductivity < O.OO0078 mhos.The tetrachloride, similarly prepared,and freed from chlorine by prolonged passage of a current of air, isa colourless liquid, b. p. 86.5" (corr.), m. p. - 49.5", n r 1.3606,4; 1.874. Both compounds fume in air and are slowly decomposedby water with a characteristic crackling sound, but are unchangedby strong sulphuric acid.%As an outcome of general investigations 36 on tlhe preparation ofgaseous metallic hydrides by the spark discharge and from alloysand solutions germanium hydride has been shown to have thecomposition GeH, and to be free from any considerable amount ofother hydrides.37 By a modified form of the Marsh test, the formationand decomposition of the hydride may be used as an extremelydelicate test for germanium; and it may be estimated gravimetri-cally by precipitation as magnesium orthogermanate, MgGeO,.%Stannous hydroxide, prepared by precipitating aqueous stannouschloride with sodium hydroxide or ammonia, is stable in air, wetor dry, up to 110", dissolves in acetic acid to form stannous acetate,Sn(C2H30,)2, has probably the formula 3Sn02,2H20, and by keepingunder water is converted into dark grey, crystalline stannous oxide,which is dispersed to a yellow, colloidal solution by excess of water.39The change of a-stannic acid to p-stannic acid is explained as dueto the combination of stannic hydroxide (functioning as a base)with itself (functioning as an acid), and the theory receives supportfrom measurements of the relative strength of the hydroxide asacid and as base considered in conjunction with the solubility of thea- and p-forms in hydrochloric acid and caustic alkali, as to whichnew facts are adduced.40The existence of lead monoxide in two forms, recently denied,llhas been conclusively proven.By slow cooling, solutions of leadoxide in aqueous caustic potash yield, according to the concentrationof alkali, relatively large crystals of either the stable red tetragonal35 L. M. Dennis and F. E. Hance, J . Amer. Chern. SOC., 1922, 44, 299;36 F. Paneth et al., Ber., 1922, 55, [B], 769, 775; A., ii, 383.3 p F. Paneth and E. Schmidt-Hebbel, ibid., 2615; A., ii, 776.38 J. H. Miiller and N. H. Smith, J . Amer. Chem. SOC., 1922, 44, 1909;38 F.W. Bury and J. R. Partington, T., 1922, 121, 1998.4O G. E. Collins and J. K. Wood, ibid., 441, 1122, 2760.41 S . Glasstone, ibid., 1921, 119, 1914.A., ii, 302.A., ii, 775; J. H. Miiller, ibid., 2493; A . , 1923, ii, 4352 ANNUAL REPORTS ON TKE PROGRESS OF CHEMISTRY.form or the metastable yellow rhombic bipyramidal form; andthese forms differ in density, in solubility, and in E.M.P. againstlead in normal caustic s0da.~2 There is some evidence that theseforms are enantiotropic; but this point is in doubt, and furtherinvestigation is required to establish their relationship. Furtherphysical investigation of the oxides of lead confirms the view ofred lead as plumbous orthoplumbate and indicates the probableexistence of a higher oxide in electrolytically deposited lead dioxide.&Examination of the X-ray spectra of rare-earth oxides hasidentified Urbain's celtium as the element of atomic number 72,intermediate between lutecium, 175, and tantalum, 181.5, and amember of this group."Group V .Formation of ammonia in good yield from hydrogen and excessof nitrogen in electron tubes occurs with applied electromotiveforces equal to or greater than the ionisation potential of nitrogen ; 46which is held to show that ionisation of nitrogen is the first step inthis synthesis.Decomposition of ammonium nitrate proceeds normally a t210-260", yielding 98 per cent.nitrous oxide, but the presence ofeven 0.1 per cent. of ammonium or sodium chloride, or the over-heating of the pure nitrate, gives impure gas containing 30-50 percent.of nitrogen; with the pure salt, the subsidiary reactions areprobably NH4N0, Z NH, + HNO, and 5NH, + 3HN0, __f9H20 + N,, and the explosive decomposition at 300" may berepresented as 8NH4N0, --+ 16H2Q + 2N0, +- 4N0 + 5N,.4GAmmonium chlorate is perfectly stable in cold saturated aqueoussolutions, but if solid salt is present progressive decomposition occurswhich finally becomes explosive; the solid decomposes, rapidly ifenclosed, slowly if exposed, the residue being ammonium nitratefree from chloride. These phenomena are due to autoxidation,cetalysed by the products of decomp~sition.~'A simple method has been described for the preparation ofcrystalline hydroxylamine by interaction of equivalent quantitiesof the hydrochloride and sodium ethoxide in absolute alcohol;4* M.P. Applebey and R. D. Reid, T., 1922, 121, 2129; see also F. M.Jaeger and H. C. Germs, 2. anorg. Chem., 1921, 119, 145; A,, ii, 65.48 S. Glasstone, T., 1922, 121, 58, 1456, 1469, 2091.44 A. Dauvillier, Compt. rend., 1022, 174, 1347; A,, ii, 463; G. Urbain,46 E. B. Andersen, Z . Physik, 1922, 10, 54; E. Hiedmann, Chem. Ztg.,46 H. L. Saunders, T., 1922, 121, 698.4 7 F. Fairbrother, J . Amer. Chem. SOC., 1922, 44, 2419; A., 1923, ii, 27.aid., 1349; A., ii, 505.1921, 45, 1073; A,, ii, 562; A., 1921, ii, 694INORGANTC CBBMISTRY. 53the product differs from the purest hydroxylamine hitherto obtainedonly in being rather less stable.&The mechanism of absorption of oxides of nitrogen by alkali isstill in doubt; further evidence supports the view that oxidationof nitric oxide to nitrogen tetroxide proceeds without intermediateformation of nitrous anhydride; yet the absorption of a gaseoussystem NO-NO, by alkali hydroxide proceeds in a manner which canbest be explained by assuming the presence of nitrous anhydridein small concentrations.4Q The fact that nitrogen pentoxide hasunusual stability in presence of traces of ozone 60 is best explainedby the assumption that its decomposition is catalysed by the pro-ducts (which are reconverted immediately to pentoxide by ozone),as has been shown to be the case in the photochemical decompositionof nitrogen pentoxide and in the thermal decomposition of itssolutions in carbon tetrachloride and chloroform.61Evidence of the existence of an active form of hypophosphorousacid is again obtained from a study of its rate of reaction withcupric chloride ; but any purely physical explanation 52 is rejectedin favour of the idea that there may exist an equilibrium betweenthe ordinary acid and its tervalent form, HP(OH),, which would beexpected to be very reactive.mTwo interesting methods are described for the purification ofphosphoric oxide, hitherto a very tedious and wasteful operation,very necessary in precise work, but often omitted.In one the oxide isdropped into a rapid current of oxygen in an iron tube a t 600-700",the sublimate being condensed in a long wide glass continuationtube; 50 grams of pure oxide can thus be prepared from 100 gramsof crude material in an hour.% The second method is ingeniousand very simple : commercial phosphoric oxide is heated a t 175-220" in ozonised air until fully oxidised : the product still contains,of course, any non-volatile impurity originally present, but it isfree from lower oxides and is no more liable than the resublimedoxide to yield gas in high vacua. Evidence was obtained that thephosphorous oxide prewnt in commercial phosphoric oxide reacts48 H.Lecher and J. Hofmann, Ber., 1922, 55, [B], 912; A., ii, 442.4@ E. Briner, S. Niewiazski, and J. Wiswald, Helv. Chim. Acta, 1922, 5,432; A., ii, 563; F. Foerster, Ber., 1922, 55, [B], 490; A . , ii, 284; A. San-fourche, Compt. rend., 1922, 175, 469; A., ii, 762.60 F.Daniels, 0. R. Wulf, and S. Karrer, J . Amer. Chem. SOC., 1922, 44,2402; A., 1923, ii, 24.61 Daniels and Johnston, ibid., 1921, 43, 5 3 ; R. H. Lueck, ibid., 1922, 44,757 ; A., ii, 433.52 Ann. Reports, 1921, 18, 41.63 A. D. Mitchell, T., 1922, 121, 1624.54 G. I. Finch and R. H. I(. Peto, ibid., 69254 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTBY.with water to form phosphine which, under the influence of electricaldischarges (for example, produced by friction between mercury andglass), reacts with mercury to form the phosphide (Hg,P2?) andhydrogen .55Phosphine, with but little hydrogen, is best prepared by the actionof 10 per cent. sulphuric acid on aluminium ph0sphide.MA review of the past evidence and consideration of new experi-ments on the heat evolved by arsenic in cooling from various hightemperatures confirm the transition point to yellow arsenic a tabout 750", but indicates that mhilst brown or "amorphous"arsenic may be, as has been supposed, a distinct monotropic modi-fication, "grey" arsenic is probably not an allotropic form, butmerely an intermediate stage in the conversion of colloidal arsenicto the crystalline state.57 This is clearly a case in which X-rayanalysis might give important information.Arsenic combines with aluminium at 750" to give a brown,amorphous compound, Al,As,, infusible and undissociated attemperatures up to 1600°, but apparently dissociating a t theordinary t'emperature, as old specimens slowly deposit yellowarsenic and leave a residue of black arsenic on solution in liydro-chloric acid, whereas the freshly prepared substance is completelysoluble in a ~ i d .~ 8Bismuth subiodide, Bi& has becn obtained in red, orthorhombicneedles, which dissolve in aqueous potassium iodide to an orangesolution, act as a strong reducing agent, and decompose to thetri-iodide and bismuth a t 400°.5gIt has been stated that tantalum pentachloride is a good conductorwhilst columbium pentachloride is an insulator, but measurementswith the anhydrous chlorides show that the conductivities are aboutthe same and extremely small, about 0.25 x mhos.60Group V I .Liquid U Z O ~ arid oxygen are only partly miscible, and are readilyseparated by fractional distillafion. Pure ozone so obtained hasbeen employed for a redetermination of physical constants (m.p.- 249.7"; b. p. - 112.4"; Tk - 5"; P k 64.8 atm.; d-lS2" 1.71),61and for an ingenious and skilful determination of vapour density5 5 J. J. Manley, T., 1922, 121, 331.56 L. Moser and A. Brukl, 2. anorg. C'hern., 1921, 121, 73; A., ii, 393.j7 P. N. Laschtschenko, T., 1922, 121, '372.5 5 Q. A. Mansuri, ibid., 2272.59 H. G. Denham, J. Amer. Chcin,. Soc., 1021, 43, 2367; A., ii, 218.Go W. Biltz and A. Voigt, 2. anorg. Chena., 1921, 120, 71; A., ii, 302.61 E. H. Riesenfeld and G. M. Schwab, Ber., 1922, 55, [B], 2088; A.,ii, 637; 2. Physik, 1922, 11, 12; A., ii, 761fNOR(3ANTC CETEMISTRY. 56by direct weighing of a bulb fdled with ozone, the pressure a t thetime of filling being extrapolated from the observed growth ofpressure in the bulb after weighing.The molecular weight foundconfirms the formula 03,62 and neither investigation affords anyevidence whatever of the existence of higher polymerides of oxygen,Ozone oxidises nitrogen tetroxide instantly to the pentoxide, thecompletion of the quantitative reaction N204 + 0, -+ N,O, + 0,being sharply indicated by disappearance of colour, so that a truetitration can thus be performed in the gaseous phase.63Sulphur dioxide partly oxidises cuprous chloride in concentratedhydrochloric acid according to the equation (i) 2Cu2C1, 4- SO, +4HC1 4CuC1, + 2H,O + S ; but the reverse change is obscuredby a secondary action, (ii) GCuCI, + S + 4H20 --t 3Cu,CI, + 6HC1+H,S04.With increasing acid concentration, h t cuprous sulphide,then mixtures of the sulphide and sulphur, and finally sulphur onlyare precipitated. A reaction analogous to (i) occurs with mercurouschloride in hydrochloric acid concentrations from 8N to 2N, whilstfurther reduction occurs (a) to mercurous chloride and mercury at3N - 0-16N, and ( h ) to mercury only at acid concentrations lessthan 0.0ZN.64Sodium sulphite or bisulphite, dropped into warm dilute aqueoussulphuric acid, yields hydrogen sulphide, probably by the reaction4H2S03 --+ H2S + 3H2S04, which may well be an intermediate stagein the known reaction 3H,S03 --+ 2H,S04 + H,O + S ; 66 andthere is evidence that hydrated sodium sulphite, excluded from air,undergoes autoxidat'ion to sulphate.66Freshly prepared solutions of bisulphites show an absorptionband characteristic of metabisulphites and therefore probablycontain a small proportion of the latter in equilibrium; they arestable in light if oxygen is excluded, but in its presence are oxidisedwith formation of sulphate and develop an absorption bandcharacteristic of hydrated sulphur dioxide.67Measurements of viscosity, conductivity, and contraction onmixing show that a complex, H2S04,H,0,(C2H5)20, is present insystems of sulphuric acid, water, and ether.68Aluminium selenide, AlzSe3, easily prepared from its elements6s S.Karrer and 0. R. Wulf, J. Amer. Chem. Xoc., 1922, 44, 2391.(i3 0. R. Wulf, F. Daniels, and S. Karrer, ibid., 2398; A., 1923, ii, 23.W. Wardlaw and F.W. Pinkard, T., 1921, 121, 210; L. M. Stewart6 5 G. M. Bennett, ibid., 1922, 121, 1794.61i S. L. Shenefield, F. C. Vilbrandt, and J . R. Withrow, Chem. and Met.67 E. C . C. Baly aqd R. A. Bailey, T., 1922, 121, 1813.6 8 J. R. Pound, ibid., 941.mid W. Wardlaw, ibid., 1481.&ng., 1021, 25, 953; A., ii, 4556 A N ~ A L BEPORTS ON mm PROGRESS OF CHEMISTRY.as a light brown powder, unstable in air, affords, by reaction withacids, a convenient source of hydrogen selenide, which can bepurified by liquefaction a t - 80" and re-evaporation. The drygas is stable in ordinary daylight and unaffected by dry oxygen.69Hydrogen telluride has becn prepared in a similar way and resemblesthe selenide except in its lesser stability to light and o~idation.'~Further work is recorded on the properties of selenium oxychloride, 71and the oxybromide has been obtained, by the action of bromineon a mixture of selenium and selenium dioxide at 0", as a reddish-yellow solid, m.p. 41.5", b. p. 217"/740 mm. with much decomposition,d50" 3-38, which generally resembles the oxychloride in its remarkablechemical activity.72A convenient method is described for the preparation of seleniumdioxide by combustion of selenium in oxygen containing nitrousfumes; 73 and it has been shown that it forms only one hydrate,Se0,,H20.74 Nitrosylselenic acid, NO*O*SeO,*OH, obtained by theaction of liquid nitrogen trioxide on anhydrous selenic acid, is acolourless, crystalline solid melting a t 80" with decomposition andunstable even at the ordinary temperature.75Tellurium, purified by distillation and crystallised by solidificationor sublimation, has d 6.310, which is unchanged by long heating a tvarious temperatures.It is probable, therefore, that telluriumdoes not exhibit the dynamic allotropy which has been attributedto it.76 Oxidation of tellurium tetrachloride wibh chlorine is aconvenient method of obtaining pure telluric acid in almost theoreticalA study of the solubility of chromium trioxide in sulphuric acidshows that when the concentration of the latter is 55-95 per cent.the solid phase is brown, minutely crystalline CrO,,SO, ; whilstin stronger acid the solid phase is probably the chromisulphuricacid, CrO,,SO,,H,O, described by Gay-Lussac and recently prepared,together with the corresponding chromiselenic acid and certain saltsof these acids.7gyield.77L. Moser and E. Doctor, 2. anorg. Chcm., 1921, 118, 284; A., ii, 46.V. Lenher, J. Amer. Chem. SOC., 1922, 44, 1664; A., ii, 706; compareAnn. Reports, 1921, 18, 53.72 Idem., ibid., 1668; A., ii, 707.73 J. Meyer, Ber., 1922, 55, [B], 2082; A., ii, 639.74 W. Manchot and K. Ortner, 2. anorg. Chem., 1922,120,300;75 J. Meyer and W. Wagner, Ber., 1922, 55, [B], 690; A., ii, 372.7 6 A. Damiens, Compt. Fend., 1922, 174, 1344, 1548; A., ii, 498, 562.7 7 J. Meyer and H. Moldenhauer, 2. anorg. Chem., 1921, 119, 132; A.,78 L. F. Gilbert, H. Buckley, and I. Masson, T., 1922, 121, 1934.79 J. Meyer and V. Stateczny, 2. anorg. Chem., 1922, 122, 1; A., ii, 773.7O L. Moser and K.Ertl, ibid., 269; A., ii, 48.A., ii, 283.ii, 49INOBGANI(3 CHEMISTRY. 57The dichlorides of molybdenum, tungsten, and tantalum havebeen prepared, in some cases by new methods, and have been shownuniformly to be represented by the formula HM3C1,,4H,0 and notby the complex formuh hitherto given to them.80Metallic tungsten acts slowly on thoria at 2400" in a vacuum andin argon, nitrogen, or hydrogen to form thorium and tungstentrioxide, the latter appearing in part to react with tungsten to forma grey, metallic, crystalline substance, very stable to acids andalkalis, which may be a " bronze " of the type Th(WO,),, wheren = 3 - 10.81The green colour sometimes observed in tungsten trioxide iedue to surface reduction to lower oxides,g2 and X-ray examinationof the hydrated oxides shows the existence of H2TV04 and H4W0,as distinct compounds,83 the former being confirmed also by theform of the vapour pressure-composition curve.84 Evidence hasbeen obtained that the sodium tungstate, 4Na20, 10W03,23H,0, isreally an acid salt, 4(Na,W0,),6(H,W0,),17H20, and correspondingsalts of other bases, differing, however, in water content, have beenisolated.86An icositetrahydrate of uranyl nitrate, U02(N03),,24H,0, isfound to exist a t temperatures below - 20O.86Group V111.The photography of the spectrum of fluorine, excited by thedischarge between gold electrodes, deserves mention because of +,heattendant experimental diffic~lties.~~ A simple method for thepreparation of pure ammonium hydrogen fluoride consists in treatingaqueous hydrofluosilicic acid with excess of amrdonia, filtering,concentrating in platinum, and subliming the product.88The existence of HCIBr,, deduced by Berthelot from the heat ofsolution of bromine in hydrochloric acid, is confirmed and that ofHCII, and HBr12 evidenced by measurements of the distributionof free halogen between aqueous halogen acids and an immisciblesolvent .89The normal chlorites of sodium, lithium, calcium, strontium,80 I<.1,intlnc.r r t d, Ber., 1923, 65, [BJ, 1458; A., ii, 509.81 C. J. Smithells, T., 1922, 121, 2230; compare E. Wedekind, EdeE-a2 J. A. M. van Liempt, 2. anorg. Chem., 1921, 119, 310; A., ii, 73.e3 I3. C. Burger, ibid., 1922, 121, 240; A., ii, 508.a4 G.F. Hiittig and B. Kurre, ibid., 1922, 122, 44; A , , ii, 773.a 5 E. F. Smith, J . Amer. Client. Xoc., 1922, 44, 2027; A., ii, 774.a 6 F. E. E. Germann, ibid., 1466; A., ii, 649.13' W. R. Smythe, Astrophys. J . , 1921, 54, 133; A . , ii, 99.8 8 M. Ikawa, J . Chem. SOC. Japan, 1921, 42, 768.s* P. RAy and P. V. Sarkar, T., 1922,121, 1449.Erden und -Erze, 1922, 3, 10958 ANNUAL REPORTS ON THE PROGRESS OF CI~EMISTRY.and univalent thallium have been prepared and are found to beunstable substances, exploding when dry by percussion and decom-posed by heat, in the case of the sodium salt according to theequation 3NaC10, -+ 2NaCI0, + NaCLgoAn examination of the mineral fluocerite by means of the X-rayspectrograph has given indications 91 that' it may contain the elementof atomic number 61, a member of this group.Group V I I I .The amount of electrolytic iron foil dissolved by aqueous sulphuricacid (in thirty-four hours at 15') has been found to vary with acidconcentration in a remarkable manner, rising steadily with 0 6 N -to 2N-acid, then falling with 3N-acid, and again increasing toprogressively higher values with 4N- and 5N-acid.Anotherseries of experiments shows that when a disk of pure iron is rotatedfor thirty minutes in acids of concentrations N/5, N/10, N/50, andN/100, the amount of iron dissolved depends only on the velocityof rotation, with which it increases linearly up to a peripheral speedof 35 m.p.h., in marked contrast to the corrosion of iron in aeratedwater, which ceases a t a speed of 5 m . ~ . h . ~ ~Samples of ferric oxide prepared by twenty-seven different methodshave been found to give identical X-ray spectra, which affords strongevidence that, despite their outward differences, they are really thesame form of the compound.93 A peculiar iron salt, FeS04C1,6H20,has been obtained by treating a concentrated solution of ferroussulphate with chlorine, and by other methods.94It is satisfaciory to record the publication of a study of the generalequilibrium in the system Fe2O3-SO3-H2O from 50-200" whichresolves in a convincing fashion the doubt and complexity associatedwith the hydrates and sulphates of ferric oxide. The componentsin suitable proportions were heated together in sealed tubes fortimes so prolonged as to ensure the attainment of equilibrium (itsnon-attainment being the probable cause of uncertain and conflictingresults in many previous investigations of the system), and theliquid and wet solids were separated and analysed. Determinationof the composition of the dry solid phase mas effected by Schreine-makers's " residue " method, controlled by microscopic observations,especially of refractive index and dispersion. The results, embodied31, i, 212, 370; A., ii, 567.90 G. R. Levi, Gazzetta, 1922, 52, i, 417; Atti R. Accad. Lincei, 1922, [v].A. Hadding, 2. anorg. Chem., 1922, 122, 195; A., ii, 780.92 J. A. Newton Friend and J. H. Dennett, T., 1922, 121, 41.93 J. A. Hedvall, 2. anorg. Chem., 1922, 120, 327; 121, 217; A., ii, 300,381.0. R6hm, Collegium, 1921, No. 614, 282; A., ii, 648INORGANIC CHEMISTRY. 59in a series of triangular diagrams and a solid model, indicate that theonly solid phases existing within the range studied are : 96 Fe203;Fe20,,H,0 ; 3Fe2O3,4S0,,9H,O ; Fe20,,2SO,,H,O ; Fe,03,2S0,,5H20 ;2Fe20,,5S0,, 17H,O ; I?e2O3,3SO3 (two forms : rhombohedra1and orthorhombic) ; Fe,03,3S0,,6H,0 ; Fe,0,,3S0,,7H20 ;Fe20,,4SO,, 3H20 ; Fe20,,4SO,, 9H,O. Other investigations confirmthe existence, as phases stable in part of the system a t 18" and 25",of Fe,0,,3S0,,7H20 and Fe,0,,4S0,,9H,0.96 The colourless formof iron alum occasionally encountered is shown to be due to thepresence of ferric hydroxide as an irnp~rity.~'In the course of further studies on the properties of subsidiaryvalency groups, the trihydrate and tri- and hexa-ammines ofcobaltous fluoride have been prepared.9*Aqueous solutions of ruthenium tetroxide conduct electricity,have a weak acid reaction, and form salts with alkalis ; but of theseonly the ammonium sali;, (NH,),RuO,, could be obtained in a purestate.9995 E. Posnjak and H. E. Merwin, J. Amer. Chem. SOC., 1922, 44, 1966;A., ii, 772.M. P. Appleby and S. H. Wilkes, T., 1922, 121, 337.97 J. Bonnell and E. P. Perman, T., 1921, 119, 1994.g8 G. L. Clark and H. K. Buckner, J . Amer. Chem. SOC., 1922, 44, 230;A . , ii, 300.F. Krauss, Z. anorg. Chem., 1921, 119, 217; A., ii, 75.€I. V. A. BRISCOE

ISSN:0365-6217    

DOI:10.1039/AR9221900030

出版商:RSC    

年代:1922

数据来源: RSC

摘要:

ORGANIC CHEMISTRY.PART ~.-AT,TPHATIC DIVISION.THE general arrangement of the aliphatic compounds which wasadopted in previous Reports has been followed in the present case,and, whilst the headings of the different sections indicate broadlythe character of the compounds considered in the various groups,an arbitrary choice has sometimes to be made. Theoretical dis-cussions based on an extended survey of reactions obviously presentthis difficulty to the Reporter, and it is imperative that generalis-ations such as those which have appeared on the induced polarityof atoms, and the interpretation of the. theory of part,ial valencieson an electronic basis, by Lapworth and by Kermack and R.Robinson,l should not be relegated to any single sub-section ofcompounds. These authors have now reviewed t'heir generalis-ations in the light of the Thomson and Lewis-Langmuir theory ofthe atom and of valency, and this may be regarded as a physicalbasis for their hypotheses.Whilst it is impossible in a sectionalreport to do justice to these theoretical considerations inasmuchas they cover the whole field of reactions in organic chemistry,nevertheless occasional references will be found in t h p succeedingpages.Hydrocarbons.A notable feature of the recent researches on hydrocarbonsis the tendency to focus on the study of the additive reactions ofthe simpler unsaturated members of the group. Attention hasbeen directed to the conditions governing the hydrogenation2 ofethylene and acetylene in the presence of nickel or of nickel-mercury catalysts.With the latter, acetylene may be reducedat 25-35" to both a light oil consisting of ethylenic hydrocarbonsand a heavier oil. In the preparation of either ethane or ethylenefrom acetylene, it is advantageous to dilute the acetylene with theexpected products. Combination of anhydrous sulphuric acid withacetylene occurs under pressure at 0" in presence of mercuricE. K. Rideal, T., 1922, 121, 309; K. Oda, J . Chem. Tnd. Japan, 1921,* T., 1922, 121, 416, 427.24, 1161; A,, 1921, i, 841.6OWANIO OHEBiISTRY. 61sulphate 3 with the almost quantitative formation of vinylsulphuricacid, CH,:CH*SO,*OH. Acetonitrile is produced a t higher tem-peratures by combination of acetylene with ammonia, but, inpresence of excess of the former, pyrrole and picoline are amongthe products.Similar evidence of polymerisation of a hydrocarbonduring its combination with other reagents is furnished in thecase of ethylene, which, under the influence of the silent discharge,unites with nitrogen to give a complex nitrile, C18H3,*CN.The catalytic method for the dehydration of alcohols has beenapplied in a preparation of pure propylene, the physical constantsof which have now been determined with accuracy.* It is ofinterest that this gaseous hydrocarbon is formed by isomericchange from cyclopropane a t 600-700" ; the reversible reaction,cyclopropane propylene, is t)hus an example of the three-carbontautomerism which has been studictd by Thorpe and his school.Consideration of the kinetics of open-chain compounds and tlhermo-chemical dat,a accord with the view that the Baeyer strain t'heoryas applied to double linlrings is open to criticism, since it is knownthat an ethylenic bond is more easily formed than a five-memberedring.5 Quite different in character is the reaction which leads,under similar conditions to the above, from ethylene to butadiene,6in which case a synthetic operation is involved with loss of hydrogen.The hydrocarbon synthesised from pinacolin by the applicationof the Grignard reagent followed by dehydration has the formulaCMe,*CMe:CH,, which undergoes reduction by Paal's method toa new heptane, trimethylisopropylmethane.When pinacolin ischlorinated by phosphorus pentachloride, the normal &chlorideis produced along with the unsaturated derivative, CMe3*CC1:CH,.Elimination of hydrogen chloride leads to a dimethylbutinenewhich on reduction gives rise to P P-dimethylbutane.Physicalconstants of these hydrocarbons have been determined.Separation of two geometric isomerides by fractional distillationis a simple procedure in the case of maleic and fumaric acids, buti t would appear difficult of achievement with hydrocarbons,Success has, however, been attained in the separation of the twoa Brit. Pat. 156121 and 147087; A., i, 517; A., 1921, i, 852; Miyamoto,J . Chm. Soc. Japan, 1922, 43, 21; A., i, 418.M. Traute and K. WinkIer, J . pr. Chem., 1922, [ii], 104, 44, 53; A.,i, 909, 926,ti J. P. Wibaut, Rec. trav. chim., 1922, 41, 441; A., i, 909; WojnicziSianomencki, &xzniki Chemji, 1921, 1, 244; A., i, 330,Zanetti, Suydam, and Offner, J.Amer. Chem. Soc., 1922, 44, 2036; A,,i, 977.7 Chwatme aad hjeurre, 3uU. Soc. Chim BeZg., 1022, 31, 98; 4., i, 417;Riseegheim, W., 62; A., i, 31362 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.y - met hyl-Au-pentenes obtained from met h yldie th ylcarbinol bydehydration with p-toluenesulphonic acid :Me*g*CH,Me Me s*CH2MeTheir boiling points differ by less than 5", and the refractive indicesare distinctive. Both yield methyl ethyl ketone on oxidation,and combine additively with bromine, but hydrochloric acid effectsisomerisation of one of the stereoisomerides.Grignard reactioiis have been applied in improvements ofrccognised methods of preparing alkyl derivatives of cadmiumand mercury, whilst recent investigations with metallic carbidesprovide not only a simplified procedure for obtaining methane,but show that with superheated steam liquid products containing60 per cent.of benzene may be collected, and by conducting theprocess under appropriate pressures terpenes and higher polymerisedhydrocarbons are formed. On the analogy of the Wiirtz reaction,the anticipated result of bringing together methylene iodide andaluminium in anhydrous ether is the formation of ethylene. Thisconclusion is in need of verification in view of the contradictoryobservations of two independent workers; lo but it seems clearthat in any case the formation of ethylene or some analogue isonly a secondary reaction.The chief product either from methylenebromide or iodide appears to be an interesting unsaturated typeof organometallic halide, namely, CH,:AlX, which is decomposedby water or alcohol to give methane. It combines additively withiodine, yielding a saturated compound, which also reacts withwater to give methyl iodide.Investigation of all the simpler unsaturated hydrocarbons witha view to their easy recognition is a necessary preliminary to thesystematic survey of the depolymerised products of caoutchouc,and this inquiry may well run parallel with a serious study of theimportant phenomenon of polymerisation which, not alone in thehydrocarbon series, but also in t)he carbohydrate group, is a vitalfactor governing the constitution of the more complex naturalproducts.Polymerisation of vinyl chloride in ether or alcohol is promotedby extreme ultra-violet light at the ordinary temperature, andmetallic salts, especially those of uranium, catalyse the reactionin sunlight.The product is a white powder which separates from0. Ohmann, 2. phySilCal. Chem. Unterr. 1921, 34, 76; A., i, 2; Plaueonand v. Tischenko, Cheni. Zentr., 1922, ii, 442; A., i, 818.10 Faillebin, Cornpt. rend., 1922, 174, 112; A., i, 119; V. Thomas, ibid.,4 64; A., i, 330.H-C*Me MeOM8 Rissegheim, Bull. SOC Chim Belg., 1922, 31, 213; A., i, 909ORGANIC CHEMISTRY. 63solvents as an elastic film. l1 Hydrogenation of caoutchouc inpresence of platinum leads to a product (C5H& which remainsa colloid and apparently is not depolymerised.Distillation ofthis product in a high vacuum yields degraded products which aresimple unsaturated hydrocarbons. The results favour the theorythat the caoutchouc molecule is composed of isoprene polymerisedin chains of such length as to minimise their unsatiirated character.The views of Harries are contested on several grounds.Thiele’s theory of the mode of attachment of addenda to a con-jugated unsaturated system such as that of isoprene is supportedby Staudinger and his co-workers, who have shown that both withhydrogen bromide and bromine combination occurs in the cc- and&positions. Whether this is so under all conditions remains indoubt, since contradictory evidence is furnished by A.G. Berg-mann .I2In the communication by Kermack and Robinson referred to inthe introduction the theory of partial valencies and the attachmentof addenda is interpreted on the basis of the Lewis-Langmuirhypothesis and it is shown that the usual expressions,CH,XCH-C -CHi - .-*. . . .3- - CH,=CE-CH=CH, +become (if it is assumed on the physical basis that the symbols-, ----, , imply electrons to the number of four, three, two,and one, respectively, held in common by two atoms) the following :CH,iCH:CHiCH,- ---- - - ,CH, iCH iCH i 6H2 - +The latter represents an extreme and unstable condition of theformer non-polarised molecule, and another more stable formwould be the cyclic one, such as :CH i CH CH-CHGH, 6H2 CH, .**CH,The system may be an oscillating one in which the terminal carboilatoms become in turn feebly electropositive and electronegative,the reagents taking advantage of these momentary manifestationsof polarity; the process of addition is represented by an inter-change of electrons of which the following is one example :CH,iCH:CH;CH, + CH,iCH:CHiCH, --tor I i i ILCK, i CH i CH i CH, CH, : CH i CH CH, ..:c1: : c1: + * *11 J.Plotnikow, 2. wiss. Photochem., 1922,21, 117; A., i, 419; H. Staudin-ger and J. Fritschi, Hdv. Chim. Acta, 1922, 5, 785; A., i, 1043.l2 Helt.. Chim. Acta, 1922, 5, 743; A., i, 978; J. Rum. Phye. Chem. Soc.,1920, 52, 34; A., i, 1106.0 . :*c1 ... c1: D.. . 64 ANNUAL REPORTS ON THE PROGBESS or C H E ~ T R Y .It is recognised, however, that other phases of interchange must beprovided for to admit of alternative modes of addition underconditions such as those which lead either to trimethylene dibromideor propylene dibromide by the union of hydrogen bromide andally1 bromide, and these manifestations of " secondary conjug-ation" are dealt with.With a substituted system such as thatwhich occurs in muconic acid, the attachment of hydrogen followsthe Thiele rule, but bromine, on the contrary, combines in the6- and P-positions, and it is suggested 13 that the rule has beentoo hastily accepted as a generalisation on evidence which isrestricted. It is contended that the Thiele rule should be confinedto those cases of conjugation in which X and X' in the formulaXCH-CH-CHXCHX' are both fully saturated residues.Experiments with petroleum reveal the disconcerting fact thatpolymerisation may accompany the formation of ozonides, andsuch considerations may have to be taken into account in evaluatingthe results of constitutional work undertaken with the use of 0zone.1~A study of the constituents of paraffin wax has given promisingdata pointing to the possibility of effecting separation of theindividual hydrocarbons, but as the research is incomplete a dis-cussion of the results may for the present be held over.Thesame may be said also of several investigations in which the higherparaffins have been submitted to catalytic oxidation with air oroxygen. The problem is complicated by the tendency of the normalfatty acids to undergo further oxidation to dibasic and hydrosy-acids, so that the isolation of palmitic and stearic acids may beprevented unless means can be devised to fix these primary productsin such a way as to resist this tendency.Alcohols and Dericatives.Synthetic methods for the manufacture of methyl alcohol andformaldehyde excite the interest of all chemists, inasmuch as thedemand on these raw materials extends to both pure and appliedchemistry.As the two substances are so intimately related inorigin, it is inadvisable to separate the reviews of several processeswhich claim to have achieved success in the synthesis of both oreither of the products. Selection of the initial materials for thepurpose must obviously depend on economic factors, and theutilisation of carbon monoxide and hydrogen is reported in twoof the methods, whilst, in a third, carbon dioxide and methaneare employed.The Badische process l5 is based on the conversion18 J. P. C. Chandrasena and C. K. Ingold, T., 1922, 121, 1306.14 R. Koetschau, 2. myew Chem., 1922, 35, 509; A., i, 977.1ti Brit. Pet. 173097; A., i, 218ORGANIC CHEMISTRY. 65of lithium carbonate into formate by the agency of carbon monoxideand water under pressure and a t a temperature above 120". Thelithium formate is afterwards decomposed a t about 400" in a,current of moist hydrogen with the production of methyl alcohola'nd ketones, and the by-product in the first reaction is carbondioxide. In another process,16 purified " suction gas " or water-gas is passed rapidly over catalysts containing nickel, copper, andaluminium a t 300400" under 10 atmospheres, when it is trans-formed into formaldehyde and methane.Conversely, the oxid-ation of the latter hydrocarbon forms the basis of a third process l7yielding both methyl alcohol and formaldehyde. By oxidationof methane at 500-700" with carbon dioxide in constricted tubesmade of nickel, copper, or silver, the following reactions occur :2C0, = 2CO + 2 0 ; CH4 + 2 0 = H-CHO + H,O.The yield of methyl alcohol is favoured by a slow passage of themixed gases through the tubes and by introducing hydrogen intothe mixture. With rapid flow of gases, however, the yield offormaldehyde amounts to 56 per cent. of the methane employed.E.W. Blair and T. S. Wheeler l8 have reinvestigated the productionof formaldehyde by the circulation of mixtures of ethylene andoxygen over catalysts. By varying the conditions and the pro-portions of the mixture they were able to increase the yield offormaldehyde to 75 per cent.Alcoholic fermentation of formaldehyde solutions is effected byosmium, and methyl alcohol and carbon dioxide are produced inthe ratio of two to one, a reaction which seems to be capable ofthe following formulation : l92CH20 + H,O + CH,*OH + H*CO,H.CH20 + H*COzH CH,*OH + CO2.aThe activity of the osmium diminishes, however, rather rapidly.Simple alcohols such as those of isobutyl and isoamyl may beprepared from the appropriate Grignard reagents 2o by the agencyof hydrogen peroxide, and good yields are obtained. The characterof the initial additive compounds suggests the representation ofhydrogen peroxide by the formula 0:OH.H a t the moment of itsparticipation in the reaction :MgRX + H,02 * H*OHR*OMgX R*OH + MgX-OH + H,O.E.J. Lush, Brit. Pat. 180016; A., i, 625.l7 0. Tram, Brit. Pat. 156148; A., i, 522.J . Soc. Chem. Ind., 1922, 41, 3 0 3 ~ ; A., i, 917.lo E. Miiller, Ber., 1921, 54, [B], 3214; A., i, 110; H. Miillsr, Ezdv. Chim.2o B. Oddo a,nd R. Binaghi, Gazzetta, 1921, 51, ii, 343; A,, i, 314.Acta, 1922, 5, 627; A., i, 809.REP.-VOL. XIX. 66 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.W f i t Grignard reactions involving the use of ketones and estersusually give rise to tertiary alcohols, yet the aa-disubstitutedketones and esters lead to the formation of secondary alcohols,provided that the alkyl group in the Grignard reagent has a normalchain and contains not more than four carbon atoms.21 Sinceexcellent yields are claimed for the synthesis of secondary alcoholsby this procedure, the method is doubtless a valuable one.Acetylenic glycols of the general type OH*CRR’*CiC*CRR’*OHmay be prepared by leading acetylene) under pressure, into thesodium derivatives of ketones, the latter sodium derivatives beingeasily formed by the aid of sodamide.22 The conditions governingthe formation of another unsaturated alcohol, namely, vinyl alcohol,have been studied by Evans and Looker, whilst a new synthesisof glycerol 23 from glycollaldehyde is effected by condensationwith nitromethane, followed by reduction and treatment of theresulting aminoglycol with nitrous acid.In a similar way, glucosehas been converted into crystalline a-glucoheptol.Of the available routes to the formation of the pure representativesof the chloro- and bromo-hydrins of glycerol, that which has beenexplored by J. Read and E. Hurst 24 is to be recommended. Ally1alcohol provides a suitable starting point, and it is shown that thehypohaloginous acids combine smoothly, yielding the mono-halogenhydrins and also, as by-products, the dihalogenhydrins.A novel and welcome variation of the usual reagents for thepreparation of chlorohydrins from ethylenic hydrocarbons isprovided by the recognition that monochlorocarbamide, obtainedby chlorinating urea in aqueous solution, readily combines witholefines in presence of dilute acetic acid to give the correspondingchlorohydrin~.~~ Several new chlorohydrins and their relatedethylene oxide compounds have been obtained by this means,and, judging from the applications which have so far been studied,the reaction seems to be general. Ethylene oxide itself is of valuein preparing by a direct method the chloroethyl esters of all typesof acids.26 This gaseous oxide combines additively with acidchlorides a t their boiling point with immediate formation of estersin which the halogen is present in the alcohol residue.Anotheruse to which chlorohydrins may be put is illustrated by the almostquantitative synthesis of ethylene cyanohydrin by means of sodiumcyanide in cold aqueous solution.J. Leroide, Ann.Chim., 1921, [ix], 16, 354; A., i, 215.22 R. Locquin and S. Wouseng, Compt. rend., 1922,174, 1427; A., i, 617.2s A. Pictet and A. Barbier, Helv. Chim. Acact, 1921, 4, 924; A., i, 4.a4 P., 1922, 121, 989.25 A. Detceuf, Bull. SOC. chim., 1922, [iv], 31, 102, 169, 176; A., i, 236.2 6 J. Aitwegg and J. Landrivon, U.S. Pat. 139319L; A., i, 315ORQAWIC CHEMISTRY. 67The well-known phenomenon of the occurrence of hydrogenperoxide during the atmospheric oxidation of ether is now ascer-tained to be due to the formation of an ether peroxide 27 which isvolatile and decomposes under the influence of light, but in presenceof acidified water hydrogen peroxide is produced quantitatively.Aldehydes and Ketones.In the foregoing section devoted to the alcohols and their deriv-atives, reference is made to developments in the synthetic produc-tion of formaldehyde and methyl alcohol.Numerous researcheshave been undertaken on problems involving the study of deriv-atives of formaldehyde, and some of these have an industrialapplication. An example is the preparation of a powerful reducingagent by suspending zinc dust in " formalin " solution and passingsulphur dioxide into the mixture through a Chamberland filter.29The zinc-formaldehyde hyposulphite which crystallises fromsolution is claimed to be more economical in use for the reductionof dyestuffs than the usual reagents. Distillation of formaldehydein presence of sulphur dioxide gives rise to sulphiformin,OH-CH,*O*SO*OH, which has antiseptic and reducing propertiesand is easily decomposed into formic a ~ i d . 2 ~ A similar transform-ation of formaldehyde into formic acid by the use of catalysts isdescribed which resembles the Cannizzaro reaction.Among the novel reactions of formaldehyde may now be includedits combination with hydrogen phosphide 30 in presence of hydro-chloric acid, giving a compound of the type PCl(CH,*OH), whichis crystalline.Other combinations of phosphorus compounds withaldehydes and ketones are already known, and it is noteworthythat these are readily formed by the agency of phosphorustrihalide .Reactions which lead to the synthesis of acetaldehyde or aceticacid from acetylene continue to be actively investigated, and minoradvances in technique have been recorded during the year.Vari-ations of catalysts or the media in which they function representthe general lines of inquiry, and a difficulty has been overcomeby utilising steam for the effective removal of the acetaldehydebefore it has had opportunity to form condensation complexesin situ. In favourable circumstances, the yield of aldehydeapproaches 80 per cent. The yield of acetaldehyde in the ordinary27 A. M. Clover, J . Amer. Chem. SOC., 1922, 44, 1107; A., i, 619.ae Ph. Malveein, Ch. Rivalland, and L. Grandchamp, C-t. rend., 1921,ao Ph. Malvezin, Id. Chimique, 1921, 8, 311, from Chem. Zentr., 1921,30 A. Hoffman, J. Amer. Ckm. Soc., 1921, 43, 1684; A., i, 8.173, 1180; A., i, 8.iii, 1118; A., i, 222.D 68 ANNUAL REPORTS ON THE PROURESS OF CHEMISTRY.laboratory preparation 33.from alcohol is similarly enhanced bythe simple device of stirring the chromate mixture in order todisengage the aldehyde rapidly from the solution.Since the initiation of the Fernbach-Weizmann fermentationprocess for the production of acetone, numerous attempts have beenmade to devise uses for the n-butyl alcohol which is the accom-panying by-product. Several claims consequently appear in thepatent literature describing the conversion of this alcohol intobutaldehyde and butyric acid, and doubtless similar cheap anduseful reagents will be made available.The older methods for the reduction of acid chlorides to alde-hydes were superseded by the procedure introduced by Rosen-mund several years ago.It is satisfactory to find that the variabilityin the efficiency of the nickel and palladium catalysts in his earlierwork has been largely overcome and a more trustworthy procedureis available. Extension of this work by Rosenmund and hiscollaborators to the dialdehydes32 is illustrated by the case ofsebacicdialdehyde, C,H,,(CHO),, which is obtainable in a yieldof SO per cent. by the use of hydrogen in presence of palladisedkieselguhr and " sulphured " quinoline. Direct formation ofacetals proceeds smoothly by careful adjustment of conditions,and it is noteworthy that ammonium chloride functions equallywith hydrogen chloride as a catalyst in this c~nnexion.~~ Neutralis-ation of the acid with sodium ethoxide before isolation of theproduct has certain advantages over the earlier practice.Studies on keto-enolic tautomerism which owe so much to thework of Knorr and his collaborators have been amplified by theintroduction of interesting examples.As was to be expected,the weapons with which earlier attacks on this problem were madeare not found to be generally applicable, and neither the colorationwith ferric chloride nor the bromine titration method of K. H.Meyer is useful in all cases for the diagnosis of enol forms.34 Thevagaries of enolisation are responsible for many reactions whichare imperfectly understood, and it excites no surprise to learnthat diacetylacetone 35 has not the usually accepted open-chainformula.Reactions of acetylacetone with tellurium and seleniumtetrachlorides reveal very strikingly the residual affiity of suchcompounds, and the elegant researches of Morgan, Drew, ands1 C. E. Adams and J. Williams, J. Amer. Chem. Soc,, 1921, 43, 2420;A., i, 222.sa K. W. Rosenmund, F. Zetzsche, C. Flutsch, and F. Enderlein, Bey.,1921, 54, [B], 2885; A., i, 39; ibid., 1922, 55, [ B ] , 609; A,, i, 431.a3 R. D. Haworth and A. Lspworth, T., 1922, 121, 76.54 H. P. Kaufmann, Ber., 1922, 55, [B], 2255; A., i, 985.a 5 J. N. Collie and Amy A. B. Reilly, T., 1922, 121, 1984ORGANIC CHEMISTRY. 69Barker 36 elucidate a recondite problem. The work of J. F. Thorpe,C. K. Ingold, and their collaborators traverses the whole field oftautomeric change, and it is impossible to deal adequately with asubject of these dimensions within the confines of this Report.Pyrogenic decomposition of acetone 37 leads almost exclusivelyto scission into keten and methane, and ultimately from the keteninto carbon monoxide and ethylene, whilst with higher ketonesboth saturated and ethylenic hydrocarbons are formed by gainor loss of hydrogen by the radicles a t the moment of disruption.Such data are of value in controlling the process of acetone manu-facture from calcium acetate.Union of nitrosyl chloride with anormal parafh in sunlight illustrates a novel and indirect meansof oxidation, since heptane, passing through the stages of dipropyl-nitrosomethane and the isomeric oxime, is converted into dipropylketone.38 Auto-oxidation is a phenomenon which has been in-vestigated closely, with special reference to the inhibitory effectsof many phenolic compounds.39 Quinol, especially, suppressesthe auto-oxidation of crotonaldehyde even when the ‘‘ anti-oxygen ”is present in so slight an amount as 1 : 100,000.Acids and their Derivatices.Several papers dealing with hydrocyanic acid reflect the interestwhich attaches to its synthesis from materials of a widely differentnature, and its trimeride appears to be represented by amino-dicyanomethane.The question has been reopened as t o thecxistence of the tautomeric form, HNC, in equilibrium with tlhenormal nitrile form and evidence of this tendency is adduced.40Standard reactions for the preparation of formic, oxalic, acrylic,maleic, and fumaric acids have been revised, and a convenientmethod of obtaining pure methyl acetate is provided by digestionof 70 per cent.acetic acid with methyl oxalate. The behaviourof acids in ultra-violet light forms the subject of several papers,the halogen acids displaying a marked capacity to decompose intoparaffin halides.Great importance attaches to the precise regulation of conditionsfor the a-bromination of acids. The Hell-Volhard method leadsto variable results in different instances, and a new series of experi-2432; compare W. Mrtdelung, Annalen, 1922, 427, 35; A., ii, 344.A. Mailhe, ibid., 863; A., i, 985.i, 417.*6 G. T. Morgaa, H. D. K. Drew, and T. V. Barker, T., 1922, 121, 922,s7 (Mlle) E.Peytrd, Bull. SOC. chim., 1922, [iv], 31, 122; A., i, 222;** E. V. Lynn and 0. Hilton, J . Amer. Chem. SOC., 1922, 44, 645; A.,C. Moureu and C. Dufraisse, Compt. rend., 1922, 175, 127; A., i, 824.40 Edith H. Usherwood, T., 1922, 121, 160470 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ments41 substantiate the theories of Aschan and others that thereaction consists essentially in the addition of bromine to an enolicform of the acid, followed by loss of hydrogen bromide, and theseconditions are attained by using molecular proportions of brominealong with 2 per cent. of red phosphorus. Traces of water in theacids, or the acids themselves, serve to generate sufficient hydrogenbromide to promote enolisation, a condition which has beenfollowed in another connexion by Lapworth.Bromination ofethyl acetoacetate under conditions resembling those of gaseouschlorination leads to the a-bromo- instead of the w-bromo-com-pound.42 The expense attending the use of ethyl p-iodopropionateas a synthetic agent is obviated by substituting in its place theesters of p-chloro- and p-bromo-propionic acids which are nowobtainable from trimethylene glycol, the latter being a by-productfrom the glycerol fermentation of sugars.43A new explanation, differing from that of Claisen, for the aceto-acetic ester synthesis is furnished by an interesting paper 44 de-scribing the isolation of ketenacetal (11), as the result of spontaneousdecomposition of the primary product in ethereal suspension, orby the action of water.It is suggested that the first product ofthe condensation is the compound (I), which changes as describedabove or is decomposed by dilute acids to give ethyl acetoacetate :/OEt CH3*CO*CH2*C02Et\ONa '% CH,:C( OEt), + CH,*CO,Na (11.)The publication of other confirmatory evidence is promised, andwill be awaited with interest.Addition of hydrogen cyanide to ethyl a-cyano- p-methyl-glutaconate and its homologues occurs readily on treatment ofthe esters with an aqueous alcoholic solution of potassium cyanideor with hydrogen cyanide containing sufficient of its potassiumsalt to ensure the presence of cyanogen ions.45 With simple@-unsaturated esters such as ethyl crotonate or dimethylacrylate,the ad$itive reaction proceeds smoothly with the formation, afterhydrolysis, of substituted succinic acids,46 and similar productsmay be obtained from aldehydes by a simplified procedure involvingthe use of potassium cyanoacetate.4 2 C.F. Ward, T., 1922, 121, 1161.42 L. I. Smith, J. Amer. Chem. SOC., 1922, 44, 216; A., i, 318.43 C. A. Rojschn, Ber., 1921, 54, [B], 3115; A., i, 105.44 H. Scheibler and H. Ziegner, ibid., 1922, 55, [B], 789; A., i, 426.4 5 E. Hope and W. Sheldon, T., 1922, 121, 2223.49 Lucy Higginbotharn and A. Lapworth, ibid., 49; A, Lapworth and(1.) CH~*CO*CH,*G-OEtJ, A. McRae, ibid., 1699ORGANIC CHEMISTRY. 71Boeseken has extended his boric acid method of investigatingconfiguration by applying it to acids of different types. Mono-substituted m-hydroxy-acids, OH*CHR*CO,H, show an increasein conductivity in boric acid solutions, but this increase is greaterthan with disubstituted acids, OH*CRR'*CO,H, and this serves todifferentiate the two types.The attainment of this result isattributed to the space relation of the hydroxyl groups. It issuggested that in aqueous solution the carboxyl group is hydratedto -C(OH),, and in concentrated solution a-keto-acids contain theresidue -C(OH),*C( OH),. Careful perusal of the systematic sum-mary of the results which have been accumulated up to date willbe well repaid.47Speculation as to the mechanism of an important group ofreactions investigated by Thorpe, Ingold, and their colleaguescontinues to receive experimental fulfilment. Although theReporter can do little more within the allotted space than referthe reader to the original papers, mention should be made of thediscovery that the Michael condensation is a reversible reaction.The first recorded example of the Michael reaction was the conden-sation of ethyl sodiomalonate with ethyl cinnamate :CHPh:CH*CO,Et + CH,(CO,Et), CHPh<CH(C02Et)z.CH,*CO,EtThe reaction proceeds from left to right, giving a yield of 35 percent. of the product. If, however, the product after isolation issubmitted to the heating conditions which promote its formation,it is found that the reaction proceeds from right to left to the extentof 60 per cent., about 35-40 per cent. only remaining unchanged.The result8 furnish decisive evidence in this and other cases thata definite equilibrium is reached determining the amount of thecondensation product which may be isolated from the Michaelreaction.48 In general, the change may be representedCR,:CY*CO,Et + CH[H]X*CO,Et - -.- ?R,*CY[H]*CO,EtCHX-C02Et 'and it is suggested that this bears a striking resemblance to thethree-carbon tautomerism of substituted glutaconic esters, so thatthe latter change may be regarded as an intramolecular Michaelcondensation :?R:CY*CO,Et - ~ ER*CY[H]*CO,EtC[H]X*CQ,Et .CXC0,Et4 7 L. Boeseken, Rec. trav. china., 1921, 40, 653; A,, 1921, i, 843.48 0. K. Ingold and Powell, T., 1921, 119, 1976; C. K. Ingold,"E. A.Perren, and J. F. Thorpe, ibid., 1922, 121, 176572 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.A series of researches on the synthesis of the polyacetic acids ofmethane has reached completion and has resulted in the isolationof all the four compounds,which may empirically be considered as derivable from glutaconicacid.49The isomerism of the glutaconic acids and their derivatives isrepresented by an ever-growing literature, and the elucidation ofthis subject owes much to the work of Thorpe and Ingold.Feist and his co-workers have failed to obtain the cis- and normalforms of P-phenyl-a-methylglutaconic acid described by Thorpeand Wood in 1913, but have confirmed the isolation of the truns-form and also of a new isomeride which is described as the true cis-modification.Feist’s general conclusions 5O favour the view thatthe glutaconic acid series conforms to the ordinary type of geometricisomerism represented by maleinoid and fumaroid forms, and thatany apparent variation is one of degree and not of principle.An interesting study of the formation and properties of p-lactonessuggests the speculation that these compounds occur more commonlythan is usually supposed.51 Since the hydrolysis of p-lactones isnot a reversible change, they are conveniently derived from p-halo-genated acids by hydrolysis in neutral solution.A large number of papers deal with the relationships of thecomplex fatty acids, and the following facts emerge.The so-calledrapic acid is identical with oleic acid. A new acid isolated frompeat by Aschan and named humoceric acid is not identical withlignoceric acid from beechwood tar, since the latter is now shownto be tetracosoic acid.It is obtained on oxidising cerebronic acid,which is itself an a-hydroxypentacosoic acid and does not containa normal chain. Holde and his co-workers have isolated pureerucic acid, and the anhydrides of both this and brassidic acid andalso those of the fatty acids of linseed oil have been prepared.The positions of the double linkings in linoleic acid are allocatedby a, study of sativic acid (tetrahydroxystearic) involving pro-gressive elimination of the hydroxyl groups, and the constitutionof sativic acid is determined by alkali fusion. Caution, however,should be observed in view of the instances of a benzylic acidtransformation which are known to occur under this treatment.C.I(. Ingold and L. C. Nickolls, T., 1922, 121, 1638.F. Feist, Anden, 1922, 428, 25, 59, 68; A., i, 521.61 E. Johansson and S. H. Hagman. Ber., 1922, 56, [B], 647; A., i, 425ORGANIC CHEMISTRY. 73Electrosynthesis of azelaic and thapsic acid 52 has been achieved,and it is now clear that the latter is identical with n-tetradecane-dicarboxylic acid.Halogen Compounds.A greatly increased yield of methyl bromide is obtainable by amodified procedure 53 which eliminates the usual risk of the pro-duction of flame. The usual mixture of methyl alcohol and redphosphorus should preferably be boiled for fifteen minutes beforethe addition of bromine to the gently boiling liquid. When bromineis mixed with methylal in a freezing mixture, the chief productsare methyl bromide and dibromomethylal, CBr,( OMe),.Thelatter is an effective methylating agent, readily converting anilineinto methylaniline, sodium cinnamate into the methyl ester,B-naphthol into the ether, and sodiomalonic ester into the substi-tution derivative. 54 A convenient preparation of vinyl halidesin situ is rendered possible by distilling concentrated halogenacids in presence of calcium carbide while simultaneously satur-ating the mixture with the gaseous hydrogen halide. Certainmetallic chlorides act as accelerators, but ferric chloride promotesthe formation of dichloroacetaldehyde. 55 Chloroacetyl chloridehas been obtained by the catalytic oxidation of chlorinated ethylene,and this reagent has been applied with success in the preparationof cellulose esters.56 Various catalytic processes leading to thepolychloroethanes from acetylene have been described. Arsenictrichloride combines additively with acetylene to give the primary,secondary, and tertiary p-chlorovinylarsines, which readily undergooxidation to the corresponding derivatives of arsenic acid. Suchcompounds are reminiscent of the reactions which lead to theformation of pp’-dichlorodiethyl sulphide, and it is satisfactory toobserve that the same authors 57 have resolved many doubts asto the nature of the reaction between ethylene and the sulphurchlorides and have revealed the identity of the related productsisolated by other workers. Hydrolysis of “ mustard gas ” withalcoholic potassium hydroxide 58 gives rise to divinyl sulphide,which again forms a dichloride with hydrochloric acid, but thisproduct is the aa-dichloro-compound and is a non-vesicant, ass2 Mabel Cmichael, T., 1922, 121, 2545.5s W.Steinkopf and G. Schwen, J. pr. Chem., 1921, [ii], 102, 363; A.,64 F. Feist, 8. angew. Chem., 1922, 35, 489; A., i, 912.6 5 Brit. Pat. 156120; A., i, 517.5 6 W. L. Barnett, J. Soc. Chem. Ind., 1921, 40, 286; A., i, 232; and1921, i, 841.D.R.-P. 340872.67 F. G . Mann and Sir W. J. Pope, T., 1922, 121, 1764, 594.E.* S. H. Bales and S. A. Nickelson, &id., 2137.D74 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.indeed is the oxygen analogue of mustard gas, the isolation ofwhich is recorded,Robinson's theory of the induced polarity of atoms has stimulatedinquiry as to the labile character of certain groups in a selectedseries of compounds.In several papers, A. K. Macbeth and hiscollaborators 59 have studied this problem in great detail, andtheir general method of investigation is to submit selected halogencompounds, among others, to the action of a definite range ofreducing agents and measure by volumetric methods the natureand extent of the reducing action. Certain halides readily lose theirhalogen atoms under these conditions, and their labile characteris attributed to the development of positive polarity by reason ofthe position such atoms occupy in relation to other groups. Thesuggestion that bromomalonic esters owe the labile nature of thehalogen to the presence of an oxygen-halogen linking appears t obe a t variance with the results obtained by a comparison of theabsorption spectra of such compounds with those of ethyl malonate.The results recorded find a reasonable explanation in the theorywhich the authors have adopted.On the other hand, Gupta and Thorpe 6O find this explanationunacceptable in the cases which they have examined and preferthe tautomeric hypothesis which correlates the labile character ofhalogen atoms in selected carbon compounds with the tendencyof the latter to acquire a hydrogen atom so located as to promoteenolisation, and their theory is supported by other workers.Optical Activity.An almost unique case of the optical activation of a racemiccompound is afforded by the observation that on mixing E-malicacid with solutions of the alkali salts of racemic acid d-tartaricacid is liberated.6l A parallel example is furnished by dZ-phenyl-methylcarbinol, which undergoes catalytic dehydration in thepresence of 1 per cent.of camphorsulphonic acid a t 100" with theformation of the laevorotatory ether oxide, whilst the unchangedcarbinol was also activated.62 Rather different in principle isthe procedure adopted for the activation or partial resolution ofdZ-mandelic acid. The Z-menthyl ester on chlorination with thionylchloride, followed by hydrolysis, gives rise to Z-phenylchloroaceticacid.63 The practice of separating optical isomerides by fractional69 T. Henderson and A. K. Macbeth, T., 1922,121, 892; E. L.Hirst andA. K. Macbeth, ibid., 904; H. Graham and A. K. Macbeth, ibid., 1109.60 B. M. Gupta and J. F. Thorpe, ibid., 1896.61 A. McKenzie and Nellie Walker, ibid., 349.82 H. Wuyts, Bull. SOC. chim. Belg., 1921, 30, 30; A., 1921, i, 506.6s A. Shimomura and J. B, Cohen, T., 1921, 119, 1818ORGANIC CHEMISTRY. 75crystallisation of their salts was illustrated in the case of lacticacid by Purdie. An extension of this procedure to organic estershas demonstrated that Z-menthyl esters of atrolactinic acid andoc-hydroxy- P-phenylpropionic acid are resolvable by crystallisationfrom solvents,6* since on hydrolysis of the crystals the active acidsare isolated. The usual practice for the resolution of racerniccompounds is generally regarded as too difficult an exercise to behandled by a student as a laboratory preparation, but the simplifiedmanipulation described by Kenner in the case of methyl-n-hexyl-carbinol incidentally overcomes this objection, G5 and provides aneasy access to a useful optically active alcohol.Synthesis of optically active compounds by methods whichinvolve activation simultaneously with the creation of the systemof groupings responsible for asymmetry is the only genuine kindof asymmetric synthesis.The following recent examples 66 appearto come within this category : the cyanohydrin synthesis appliedto isovaleraldehyde and p-tolualdehyde in presence of emulsingives rise to dextrorotatory nitriles ; yeast fermentation in presenceof pyruvic acid or of acetylcarbinol leads to optically activeacetylmethyl-carbinol or Z-propylglycol, respectively.The discovery of Franchimont that ethyl tartrate is a crystallinesolid with a freezing point of 18.7" has contributed a new criterionof purity, and the admirable investigations 67 based on materialconforming to this new standard have resulted in a series ofre-determinations of specific rotation, density, refractive index,and dispersion, using light of representative wave-lengths.Theobserved specific rotations range from + 6-87' in the green to- 12.2" for the last photographic reading in the ultra-violet andinclude thirty-four values for the intermediate lines of the spectrum.The rotatory dispersion is in close agreement with that calculatedby using two terms of the Rrude equation.Comparative measure-ments of the interfacial tension between aqueous solutions of thetwo active tartaric acids and racemic acid in contact with inertliquids reveal no differences for the d- and Z-forms, but a markeddivergence from this value for racemic acid, and this is adducedas evidence of the existence in solution of the racemic acid mole-cule. On increasing the dilution, there is a clear indication ofdissociation into d- and Z-forms. It is demonstrated that the typeof union found in racemic acid is not restricted to the two anti-podes, since a like combination may be artificially produced betweenH. Wren and E. Wright, T., 1921, 119, 798.T., 1922, 121, 2540.O6 L. Rosenthaler, Pementforsch., 1922, 5, 334; A,, i, 480; J.Hirsch,Biochem. Z., 1922,131, 178; A, i, 973. Compare A., 1921, i, 150.T. M. Lowry and J. 0. Cutter, T., 1922, 121, 632.D"76 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.d- and i-tartaric acid, the complex containing one molecule of eachacid along with water of crystallisation as in racemic acid, therotatory power being thereby halved.68Evidence is available which disposes of the assumption thatracemisation of Z-mandelamide with alkali is to be attributed toenolisation. An explanation which is supported by experiment 6*is that alkali or potassium ethoxide combines additively with theamide as in the Claisen reactions, subsequent loss of water oralcohol producing an inactive compound, The changes may beexpressed :Ph.CH*OH Ph*CH*OH Ph*C*OH Ph*CH*OHI OEt-+NH,*hOK * NH,*C:Olaevo.laevo. inactive. racemio.The racemisation of the mandelonitrile residue in amygdalin isexplicable on a similar principle. The presence of a migrationalhydrogen atom on the asymmetric carbon atom appears to lead inall such cases to racemisation; this tendency is suppressed bysubstitution of a methyl group for the hydrogen atom or altern-atively by replacing the phenyl residue by benzyl. On the otherhand, the tendency is increased by the presence of a methoxyl ortolyl group in place of the hydroxyl group attached to the asym-metric carbon atom.Of the many examples of resolution into optically active formswhich have been communicated during the period under review,one of the most interesting 70 is that of the keto-dilactone of benzo-phenone-2 : 4 : 2 ' : 4'-tetracarboxylic acid shown below :,co-0--.,*H,* <OKI NH,-C:O0-co'The compound affords another example of the existence of opticalenantiomorphs containing no asymmetric atom.Theoretically,the molecule is divisible at the central spirane carbon atom intotwo identical halves, but the molecular asymmetry is attributableto the fact that these two halves lie in different planes which meetand intersect at right angles at this central atom. The resolutionhas been achieved by the use of Z-a-phenylethylamine. Taking6a Ph. Landrieu, Bull Soc. chim., 1922, 33, 667; A,, i, 808; S. W. penny-cuick, J. Amer. Chem. SOC., 1922, 44, 1133; A., i, 624.A. McKenzie and Isobel A. Smith, T., 1922,121, 1348.'O W.IT. Mills and C. R. Nodder, ibid., 1921,119, 2094ORGANIC CHEMISTRY. 77advantage of the existence of ad-dibromoadipic acids in bothmeso- and racemic forms, W. H. Perkin and E. Robinson 71 havecondensed the esters of these acids with ethyl malonate in orderto synthesise the geometric isomerides of cyclopentane-1 : 2 : 3-tricarboxylic acid :CH2-CH*C02HCH,-~HCO,HI &H*CO,HTwo of these isoinerides, the cis-trans-cis, and the cis-cis-cis, aremeso-forms and a third, the cis-trans-trans, is a ~acomic form, whichwas resolved by means of brucine.Carbohydrates.Monosaccharides.-Improved methods for the preparation of anumber of sugars and their derivatives are reported in the literatureof the year, among which are included fructose, mannose, galactose,raffinose, sorbitol, inulin, and gluconic acid.Scrutiny of theprocedure involved in the oxidation of hexoses has revealed anunexpected result. At the ordinary temperature and in the absenceof air, nitric acid transforms glucose or gluconic acid into a-keto-gluconic acid, in the formation of which the oxidation of a secondaryalcohol group is involved. 72 Fischer's degradation of d-saccharicacid by oxidation with permanganate into d-tartaric acid provedthe configuration of the groups attached to the second and thirdcarbon atoms of the glucose chain. The diamide of d-saccharicacid yields, however, Z-tartaric acid through the related dialdehydeon treatment with bromine and potassium hydroxide,73 and thisproves the configuration of the groups attached to carbon atoms3 and 4.CO,HCollateral evidence bearing on the character of the oxide linkingin simple hexoses is furnished by the synthesis of y- and 6-hydroxy-7 1 T., 1921,119, 1392.71 H.Kiliani, Ber., 1922, 55, [B], 76, 493; A., i, 223, 321.73 M. Bergmann, ibid., 1921, 54, [B], 2661; A., i, 778 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.aldehydes and -ketones.74 The location of the hydroxyl groupwith reference to the aldo- or keto-group resembles that of a sugar,and it is significant that these compounds simulate the reactionsof sugars. They form " glucosides " or semi-acetals with methyl-alcoholic hydrogen chloride, instead of the usual acetals, and theease of hydrolysis of these methyl derivatives is comparable withthat of the glucosides.Moreover, the typical aldehyde reactions,although not altogether suppressed, are modified or retarded byreason of the existence of t h e aldehydes or ketones in their morestable butylene- or amylene-oxidic forms :(1.1 (11.) (111.)(7-hydroxy-aldehyde). (6-hydroxy-aldehyde). (6-acetylbutylalcohol).Cyclic forms of:The methyl semi-acetal of I11 contains an amylene oxide ring andthe sensitiveness of this analogue of methylfructoside towardsextremely dilute acids is reminiscent of the behaviour of they-glucosides or fructosides. Should the amylene-oxidic structurebe assigned to the y-sugars, this characteristic property will receivesufficient explanation from the analogy which has been drawn.A re-investigation of the acetone derivatives of glucose indicatesthat their structure conforms t o the y-glucose type, and formulaeare ascribed to those compounds which represent 7-glucose by apropylene-oxidic structure.On the other hand, both fructosemono- and di-acetones are derivatives of ordinary lzvorotatory orbutylene-oxidic fructose, and it is remarkable that the same com-pounds me formed either from ordinary fructose or y-methyl-fructoside. 75The chemistry of glucosamine has been advanced by the recog-nition and study of the new p-form, and a comparison of its mole-cular rotation with that of the a-form shows that these valuesare in agreement with Hudson's rule if glucosamine is accepted as%aminoglucose, and a t variance with its relationship to mannose.74 B.Helferich and M. Gehrke, Ber., 1921, 54, [B], 2640; A., i, 9; B.Helferich and T. Malkomes, ibid., 1922, 55, [B], 702; A., i, 431; M. Berg-mann and A. Miekeley, ibid., 1390; A., i, 618.7 0 J. C. Irvine and J. Patttterson, T., 1922, 121, 2146ORGANIC CHEMISTRY. 79Since glucosamine has been converted into both glucose and man-nose, the latter change must involve a Walden inversion. Cbn-densation of triacetyl bromoglucosamine with salicylaldehyde doesnot occur through the phenolic group of the latter to give a gluco-side, but involves a union of the aldehyde residue of salicylaldehydewith the amino-group of the sugar. The bromine atom in thereducing position in the sugar derivative thus remains intact, andis removed by solution in alcohols and leads to glucoside formation.The latter reaction is accompanied by a gradual change of rotationwhich, in the absence of precise knowledge of the structure of thesalicylidene derivative, was formerly described as pseudo-muta-rotation. Whilst serving to elucidate an apparent anomaly in theoptical behaviour of a supposed glucoside, this research 78 furnishesadditional evidence of the tendency of glucosamine to form deriv-atives of the betaine-ring type.Thus, whilst triacetyl methyl-glucosamine combines to give an 80 per cent. yield of the salicylidenederivative and presumably exists largely as an amino-hexosecomplex, the de-acetylated methylglucosamine yields only 26 percent. of the salicylidene product, the inference being that freemethylglucosamine exists mainly in the betaine form in whichthe glucosidic methyl group is united with nitrogen, giving thecyclic complex: ~H-N-H .The capacity of glucosamine tocondense with reagents varied in type is also illustrated by itstransformation into crystalline heterocyclic compounds of theglyoxaline and pyrrole class in presence of potassium thioc yanateor silver cyanate," reactions which bear a resemblance to the firststage in Pyman's synthesis of histidine. The idea that glucose,reacting as an aldehyde, gives a glucose-ammonia which is ananalogue of aldehyde-ammonia is revived,'* but, on the otherhand, it is confbmed that glucose-anilide has the butylene-oxidicstructure and is therefore aniline-gluc~side.~~Glucosida and Disaccharides.-The recognition of the sugarresidue in amygdalin has long been a subject of dispute and Fischer'stentative suggestion that the biose may be identical with maltosehas often been misconstrued.The methylation of amygdalin hasbeen accomplished by means of methyl sulphate and sodiumhydroxide, giving the completely methylated amygdalinic eater. So76 J. C. Irvine and J. 0. Earl, T., 1922, 121,2370, 2376.77 H. P'ady and E. Ludwig, Z. phyaiol. Chern., 1922, 121, 170; A., i, 953.l 8 A. R. Ling and D. R. Nanji, T., 1922, 121, 1682; J . SOC. C'hem. Ind.,'* T. Sabalitschka, Ber. deut. Pharm. am., 1921, 31, 439; A., i, 241.8o W. N. Haworth and Gracs C. hitch, T., 1922, 121, 1921.-FH-? /Me\H1922, 41, 1 5 1 ~ ; A., i, 63180 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Hydrolysis of this compound led to the isolation of butylene-oxidicforms of 2 : 3 : &trimethyl glucose and 2 : 3 : 5 : 6-tetramethylglucose, from which it follows that the amygdalin-biose has thesame structural formula as maltose :I 0 IOH*CH2*CH( OH)dH*CH( OH)*CH( 0H)dH>OThe stereochemical formula is, however, probably different fromthat of maltose, and the biose is most likely a glucose-p-glucosideof the above structure, and may prove to be identical with iso-maltose or gentiobiose.Progress has been made in several researches on the constitutionof digitonin, which is shown to contain both hexose and pentoseresidues.The difficult problem of the constitution of the saponins,whilst continuing to engage the attention of chemists, requiresexceptional patience and resource, and it would seem that greatersuccess can only be attained by an extended study of the crystallinesapogenins, which are related to the terpenes.*l The glucoseresidue in indican appears to be of the normal butylene-oxidetype.82A biochemical synthesis of a-methylmannoside is reported 83 andalso the synthesis of new condensation complexes from helicin.PoZysaccharides.-A significant feature of the work of the yearis the unprecedented volume of researches on the constitution ofthe polysaccharides. It is only possible to reflect the generaltrend of the published results, which are often so contradictorythat little finality is to be expected at the present stage.Starch,when degraded by bacteria, gives rise to a series of products, manyof them crystalline, which are represented by a formula (C6Hlo05)n,where n is a small integer such as 2,3,4,6, 8, and these compoundsare known as the di-, tri-, tetra- (etc.) amyloses. In relation tostarch itself, these are comparatively simple substances, and theirinvestigation may obviously be expected to throw some light onthe structure of starch. On distilling potato-starch in glycerol,a new depolymerised product is isolated, differing from the abovetriamylose, but isomeric with it, and this is named trihexosan.84k Windaus and I(. Weil, 2;. physiol. Chem., 1922, 121, 62; A., i, 848;A. W. van der Ham, Rec. trau. c h h . , 1921, 40, 542; A., 1921, i, 877.A.I(. Maebeth and J. Pryde, T., 1922, 121, 1660.'8 H. H6rissey, C m p t . rend., 1921, 173, 1406; A., i, 112; R. de Fazi,Cticzzetta, 1922, 52, i, 429; A., i, 755.A. Pictet and R. Jahn, Helv. Chim. Acta, 1922,5, 640; A., i, 987ORGANIU CHEMISTRY. 81Pringsheim, Karrer, and others have resorted to the use of a com-bination of the Purdie reaction and the methyl sulphate methodof methylation in a detailed study of these depolymerised starchesand, coupled with the application of acetylating agents, haveendeavoured t o trace the simplest depolymerised unit of whichthe starch molecule is composed. This is variously regarded as(CSH1005), or (CSHlOO6),. A. Pictet has abandoned his opinionthat starch is polymerised p-glucosan, and, along with Pringsheim,regards (C6H1006)3 as the unit of starch.Karrer, on the contrary,considers that the unit is a diamylose, namely, anhydrornalto~e,8~since all methods of degrading starch had hitherto led to maltoseor polymeric forms of its anhydride. Methylation of purified rice-starch with methyl sulphate yields a product which is incompletelymethylated and on hydrolysis gives rise to two parts of dimethylglucose and one part of 2 : 3 : 6-trimethyl glucose, a result whichsuggests the view that the starch unit is a trihexosan, and thatthe partly methylated starch (OMe = 37 per cent.) contains ineach unit a trimethyl hexose residue and two dimethyl hexoseresidues. A structural formula 86 is based upon these results :I-0-l i-FH- O--CH,*CH (OH) *CH*[CH*OH],*CH0 [SH*OH], AI-QH I QH-O-FHfCH*OHI,.CH*CH( OH)*CH,CH,*OHThis formula takes into account the constitution already assignedto and it is noteworthy that Karrer's anhydromaltoseformula does not admit of the formation of the 2 : 3 : 6-trimethylglucose which has been isolated as above.It is pointed out thatordinary starch contains nitrogen and phosphorus in chemicalcombination, and an ingenious suggestion is advanced 88 that theresistance of part of the starch grain to the action of hot water oracids is due to the presence of condensed complexes of the starchunit with silicic or phosphoric acid or water, the breakdown ofwhich gives rise to the polyamyloses.In confirmation of earlier work, it is now established that cottoncellulose a t least contains only glucose residues.89 A new di-86 P.Karrer and Elizabeth Biirklin, Helv. Chim. Actu, 1922,5, 181; A.,i , 435.86 J. C. Irvine and J. Macdonald, Brit. A880C. Reporb, 1922.8 7 W. N. Haworth and Grace C. hitch, T., 1919, 115, 809.88 G. Malfitano and M. Catoire, Compt. rend., 1922, 174, 1128; A., i, 527.8s J. C. Irvine md E. L. Hirst, T., 1922, 121, 158582 ANNUAL REPORTS ON THE PROURESS OF CHEMISTRY.saccharide, celloisobiose, has been isolated by Ost and Knoth 00from the products of acetolysis of cellulose. Its physical constantsand the solubilities of its octa-acetate differentiate i t from cello-biose, and its osazone melts a t 165-167". Although hydrolysablewith greater difficulty than cellobiose, its acetate changes into aderivative of the latter sugar.A new degradation of cellulose intoa biose-anhydride is reported by H e s ~ , ~ l and its tetraethyl deriv-ative may be obtained by acetolysis of ethylated cellulose. Karrer 92has advanced a cellulose constitution which represents the mole-cule as composed of two units only of anhydro-cellobiose. It wasindicated two years ago by W. S. Denham 93 that methylation ofcellulose could be carried to the stage a t which three methoxylgroups were introduced into each CsHloOb residue, the methoxylcontent being 44.6 per cent. as compared with a theoretical valueof 45.6. The later work 94 describes the hydrolysis of methylatedcotton cellulose containing OMe = 43.0 per cent., which gave almostentirely the 2 : 3 : 6-trimethyl glucose, thus affording a proof thatthe glucose residues in cc-cellulose are identical in structure. Theabove trimethyl glucose has recently been the subject of furtherstudy 95 and the structure assigned to it by other workers is con-firmed. A formula for the cellulose unit which is based upon thesestriking results must take into account the yield of cellobiose whichis obtainable when cellulose is subjected to acetolysis, and Irvine,Denham, and Hirst suggest among others the following, which forlseveral reasons is preferred :YH,*OH ,-o-------I-CH-O-CH- CH*[CH*OH],dHI 0 [bH*OH], 0I-CH ICH,*OH I 0-CH-0-- ~H*[CH*OHJ2*$lH*CH*CH2*OHThe interesting observation is made that percolation of saltsolutions through cellulose produces an acid atrate, which suggeststhe hydrolysis of, in one case, sodium chloride to hydrochloricacid.Aqueous washings from the cellulose SO treated give analkaline solution of alkali content almost equivalent to the acidity90 ce12&8~h&e, 1922, 3, 25; A.9 L 526.*I K. Hm and W. Wittelsbach, Ber., 1921, 54, [B], 3232; A., i, 116;92 P. Ksrrer, Celldoaechemie, 1921, 2, 125; A., i, 231.93 W. S. Denham, T., 1921, 119, 77.@c J. 0. fi-ne, W. 8. Denham, and E. L. Hirst, Brit. Assoc. Reports, 1922,*6 J . C. I&e and E. L. Eirst, T., 1922, 121, 1213.K. H~ss, ibid., 2867; A., i, 12ORGANIC CHEMISTRY. 83of the salt solution. The resultant effect on the cellulose is a matterof considerable i m p ~ r t a n c e . ~ ~One af the many disconcerting factors encountered in the elucid-ation of the constitution of polysaccharides is the phenomenon ofpolymerisation and depolymerisation which may appear at anystage of the work.This circumstance is responsible for the isolationof no fewer than three types of trimethyl inulin, two of which aresoluble in ether and show rotations of opposite sign, whilst thethird is insoluble in ether. Such apparent anomalies are responsiblefor the frequent claims and counterclaims of different workers.Genuine progress has, however, been made in that it is finallyestablished 97 that inulin is composed entirely of 7-fructose residues ;these may conceivably be arranged in groups of three in the unitformula of the inulin molecule on the analogy of starch and cellulose,namely : r (c6~1,+35)3~z.Nitrogen Compounds.An inquiry 98 which will be welcomed by all chemists has beeninitiated with promising results into the mechanism of the synthesisof nitrogenous products in the plant.There is an experimentalbasis for the belief that the production of activated formaldehyde(I) from carbon dioxide under the influence of light leads, in thepresence of nitrites or nitrates, to the synthesis of formhydroxamicacid (11), the photosynthetic formation of which was establishedby Baudisch,H*C*OH ~ H*C*OH . O%*OK N*OH H*C*OH + O:N*OK -+ * * + o(1.1 (11.1and that this product enters with remarkable ease into combin-ation with more activated formaldehyde, giving rise to amino-acids and possibly proteins and alkaloids.The progress of thiswork will be watched with special interest and with the expectancythat sufficient of the laboratory products may be made availablefor debite characterisation and analysis. Significance is attachedto the observation that sustained efforts are in progress to obtainsynthetic carbamide on a considerable scale. Scrutiny of thepatent literature reveals a noteworthy attempt to replace thelaboratory methods by a direct commercial process which willO6 Helen Masters, T., 1922, 121, 2026; A. Tingle, J. Id. Eng. Chem.,1922, 14, 198; A., i, 434; E. Knoevenagel and H. Busch, CeZEulosechemk,1922, 3, 42; A., i, 636; J. Huebner and F. Kaye, J. SOC. Chern. Id., 1922,D7 J. C. Irvine, Ettie S. Steele, and Mary I. Shannon, T., 1922, 121, 1060.O 8 E .C.C. Baly, I. M. Heilbron, and D. P. Hudson, ibid., 1078.41, 94T; A., i, 43584 ANNUAL REPORTS ON THE PROGRESS OF OHEMISTRY.involve the utilisation of carbon dioxide and ammonia or of cyan-amide.The synthetic utility of cyanamide and dicyanodiamide is empha-sised by the numerous examples on record of preparations ofguanidine derivatives. The allcylated guanidines are readilyavailable by the interaction of hydrochlorides of alkylamines anddicyan~diamide.~~ The latter reagent combines with ammoniumperchlorate to give the explosive guanidonium perchlorate; whichprovides a convenient source for the preparation of guanidine andits salts.1 Condensation of ethylene chlorohydrin with cyanamideyields the cyanoamidoethyl alcohol, whence, reacting in the formNC-NHCH,*CH,*OH, guanidoethyl alcohol may be derived bycombination with alcoholic ammonia.Although orthocarbonicacid and its amino-analogue have only a hypothetical existence,yet it is interesting to consider a scheme of derivation2 whichproceeds from the formula C(NH2), by progressive loss of ammoniafrom one or more molecules to guanidine, diguanidine, cyanamide ;and from a polymeride of the latter, namely, melamine, (H2CN2),,to melam, melem, melon, and hydromelonic acid. A new memberof the series, dicyanamide, (CN),NH, is an acid which is com-parable in strength with hydrochloric acid.The synthesis of s-aminohydroxysuccinic acid has on severaloccasions been prematurely reported, but success has now beenachieved by heating chloromalic acid under pressure with aqueousamrn~nia.~ The acid so attained is a mixture of two crystallineisomerides, which give rise on treatment with nitrous acid toracemic and mesotartaric acids.Applications of the aminoethanolswhich are of service as intermediate products in the synthesis oflocal anaesthetics, continue to excite interest. Although it is notpossible to give an outline of the many synthetic compounds thepreparation of which is chiefly described in patents, yet certainnovel modes of formation may be summarised. Condensation ofa- bromopropionic acid with dimethylamine and subsequent esteri-fication lead to ethyl a-dimethylaminopropionate. Reduction of theester group is effected by sodium in alcohol, and the product is N -dimethylalaninol, Me,N-CHMe*CH,*OH, which readily gives withmethyl iodide alanine-choline iodide.The method finds applic-ation in a number of cases quoted by Karrer and his pupil^.^ Re-99 E. A. Werner and J. Bell, T., 1922, 121, 1790; T. L. Davis, J. Amer.Chem. SOC., 1921, 43, 2230; A., i, 118.1 W. Marckwald and F. Struwe, Ber., 1922, 55, [B], 457; A., i, 328; E.Fromm and E. Honold, ibid., 902; A., i, 529.2 E. C. Franklin, J. Amer. Chem. SOC., 1922, 44, 486; A., i, 440.a H. D. Dakin, J . Biol. Chem., 1921, 48, 273; A., i, 143.4 Helv. Ghim. Acta, 1922, 5, 469; A., i, 813ORGANIC CHEMISTRY. 85placement of the hydroxyl group in diethylaminoethanol by halogenand condensation of this halide with sodio-malonic and -acetoaceticesters represents another line of inquiry which is in progress, whilstthe use of Gabriel's phthalimide method in conjunction with thehalogenohydrins provides another mode of preparation of amino-alcohols.Prolonged heating of mercury fulminate a t 90" effects an im-portant change without alteration of the crystalline form and givesa non-explosive product which has been named pyrofulmin, butindications point to its not being a homogeneous ti compound.In two theoretical papers which merit attention, Staudingerreviews the reactions of ketens and aliphatic diazo-compoundsand reaches conclusions which suggest a modification of the con-stitution of the latter in accordance with the views of Thiele andAngeli.Compounds of the type R,C:NIN are termed azenes on theanalogy of the ketens, and two reactive points are indicatedRp,C:NiN< and R,C:NiN.Reactions occurring at the terminal position, involving the firstscheme of formulation, are common, such as reduction of aliphaticdiazo-compounds and addition of Grignard reagents, Manyreactions, such as the addition of unsaturated compounds, occur inconformity with the second scheme, and may be written :i iand the action of water, acids, alcohols, and amines proceeds in asimilar manner.Comparison with the reactions of ketens enablesa close analogy to be drawn.The period covered by this division of the Report is from December1921 to November 1922 inclusive, but the section on optical activityincludes also the work of the previous year.W.N. HAWORTH.PART II.-HOMOCYCLIC DIVISION.IN compiling this report the writer has endeavoured to adopt animpartial and unprejudiced point of view, but he is fully aware ofthe difficulties which may be encountered in such an attempt and,if there are occasionally signs of straying from the path, the onlyext'enuating circumstance which can be urged in mitigation of the5 Langhans, Z. ges. Schiess. u. Sprengsto#w., 1022, 17, 9, 18, 26; A., i, 338.6 Helv. Chim. Acta, 1922, 5, 87; A., i, 23886 ANNUAL REPORTS ON THE PROGRESS OB CHEMISTRY.offence is that in all probability an entirely neutral survey wouldalso be lifeless and devoid of value. Both in volume and insustained interest the work published during the year fully reachesthe pre-war level and attention may be specially directed to theseries of papers on tautomerism, ring-formation, and allied subjectswhich have been prosecuted in the laboratories at S.Kensingtonand recorded in papers which followed one another in quick successionwith almost bewildering rapidity.Constitution of Benzene.The Dewar formula for benzene has been revived by C. K. Ingold,lwho regards it as one of the phases in an equilibrated system oivalency isomerides :The argument is partly by analogy with the recently observedintra-annular tautomers (p. 113) and pastly derived from a surveyof the reactions of phenol and its derivatives.This view would be contested by few if the para-linking wereinterpreted as amounting to a relatively weak partial valency only,but the suggestion is apparently advanced in a much more uncom-promising form, to which there are obvious and serious objections.It is, for example, contrary to experience to assume that a substanceof the formula I could be so stable to permanganate as are manyderivatives of benzene.There is also the behaviour with ozone,the absence of dicyclic products of reduction processes, and, ingeneral, the absence of any degradation product of benzene or itsderivatives in which the carbon atoms in the para-position arefound to be connected. It would be beside the mark to answer thiscriticism by assuming high reactivity of the para-bond, because inthat case too high a standard of activity is set by the ethylenelinkings. A conjugated system connecting two atoms is in manyrespects the equivalent of a direct bond and naturally, therefore,very many reactions can equally well be represented as due to theintervention of either.But the theory of reversible addition toconjugated systems involves the fewer inconsistencies and is awider generalisation. Only one specific point can be touched uponand that concerns the relation of quinol to quinone. The schemegiven is :€€O\,=,/OH+ o=/=\-oHO/\=/\OH L/-- HO- /=\OH -+ \=/1 T., 1922,121, 1123ORGANIC CHEMISTRY. 87This does not accommodate the fact that dihydric phenols maybe oxidised to quinones by means of silver oxide or lead peroxidein dry ethereal or benzene solution,2 and many other argumentscould be quoted in support of the view that the relation betweenquinol and quinone is a directly reversible one involving the removaland addition of two hydrogen atoms. An extremely elegantsynthesis of orcinol is described by Ingold in Part I1 of the series,the title of which is " Synthetic Formation of the Bridged Modi-fication of the Nucleus."Ethyl @-methylmethanetriacetate (11) was converted by meansof sodium or potassium in xylene solution into a mixture of substancesfrom which it was possible to isolate ethyl 3-methylcyclobutan- 1 -one-3-acetate (111).The question of the constitution of this sub-stance is not discussed, and it must be assumed that there is someundisclosed reason why it cannot have the open-chain formula,Me*CO*CH:CMe-CH,*CO,Et, apparently a possibility.The esterI11 was obtained in very small yield and was found to undergotransformation to orcinol (IV) under the influence of sodium inei; her-benzene solution.CMeMeCMe qH,-yMe-$232 9H2 'I'CH, /\(?H2/bH2'yH2 CO-CH, C0,Et CO ' 60 ~ 0 1 IOHCO,Et bO,Et C02Et \ I / \/CH(11.1 (111.) (IV* 1Synthetic evidence is, however, generally regarded as inadmissiblein such cases, unless, indeed, two valency isomerides are sufhientlystable to exist independently as, for example, is the case withcydobutene and butadiene. It should be stated that the abovesynthesis is not regarded by its originator as a complete proof ofthe occurrence of the bridged phase of the nudeus.A new benzene model has been suggested by Fraser? but it doesnot appear to satisfy the necessary structural conditions.Briefly,it b. the most symmetrical possible arrangement of six tetrahedrawhich will fulfd the requirements of the facts of isomerism of sub-stituted derivatives and also bring the groups in the ortho-positioninto closer space relationship than those in the meta- and para-positions. The solution of this problem in geometry leads to a" twisted " Ladenburg prism formula in which each carbon atomis attached to two others in the m-positions and to the carbon atomR. Willstiltter and J. Parnas, Ber., 1907, 40, 1406; R. WilLtiitter andF. Miiller, ibid., 1908, 41, 2580.C, I(. Ingold, T., 1922,121, 1143.R. Framr, ibid., 18888 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in the p-position. It thus contains nine single bonds or, in theterminology of the octet theory, there are six octets connected bymeans of nine duplets.Adopting the hexagon convention in orderto indicate the carbon atoms in o-, m-, and p-positions, the arrange-ment of valencies is as shown in the annexed figure, which closelyresembles the stereographic projection of the model.One of the chief of the many groups of facts which are at variancewith this interpretation is concerned with the relations of aromaticand hydroaromatic compounds. Orientation in the benzene andcyclohexane series is in many cases an independent process and theresults are always in agreement with the supposition that no seriousrearrangement in the mode of linking of the carbon atoms occurswhen a benzene derivative is reduced.In Fraser’s model the un-broken cyclohexane rings are indicated by the figures 1, 2, 3, 4, 5, 6and letters a, b, c, d, e, f, and there may be other possibilities noneof which represents the succession of atoms characteristic of thereduction products. Even in the formation of dihydro-derivativesit would be necessary to delete the nine bonds and replace them byentirely new ones and it is a severe strain on one’s capacity forassimilation of new ideas. The tautomeric change of phloroglucinolinto triketohexamethylene would similarly involve an alteration inposition of each of the nine bonds. In terms of the prevailingversion of the electronic theory of valency, the problem of theconstitution of benzene becomes that of the disposition of eighteenelectrons, twelve of which may be assumed to be involved in theformation of the ring.In regard to the remaining six, numeroussuggestions have been made,5 independently, but with points of5 H. Kauffmann, “ Die VaIenzIehre,” p. 639; H. Stark, “ Die Elektrizitatin Chemischen Atom,” p. 216; H. Pauly, J. pr. Chem., 1918, [ii], 98, 118;W. 0. Kermack and R. Robinson, T., 1922,121, 437; M. L. Huggins, Science,1922, 55, 679; A., i, 997; J . Amel.. Chem. SOC., 1922, 44, 1607; A., i, 928;E. C. Crocker, ibid., p. 1618; A., i, 927ORGANIC CHEMISTRY. 89contact especia,lly in regard to the explanation of the laws of sub-stitution. The further discussion of this highly speculative subjectcannot be attempted here.It will be recalled that, as the result of the X-ray analysis ofcrystals of naphthalene and other aromatic compounds, Sir WilliamBragg concluded that the characteristic hexagonal rings arepuckered.6 More recently, somewhat modified figures for thecrystal molecules of benzene, naphthalene, and anthracene havebeen presented and are intended t o show a solution which would bein agreement with the results so far obtained.' It is, at any rate,already clear that the carbon atoms in the individual crystalmolecule do not lie in a plane.It is interesting t o note that similarconclusions in regard to cyczohexane rings have been reached asthe result of a study of the influence of stereoisomeric cyclohexane-diols on the conductivity of boric acid and of the behaviour of theglycols on condensation with acetone.8 The chief obstacle to theacceptance of the view that this arrangement is a stable one, ratherthan a phase of an oscillation which may be suppressed in crystal-lisation or in the course of a reaction, lies in the fact that numerouscases of enantiornorphism should arise in substances hithertoregarded as composed of symmetrical molecules.Although itschief interest may possibly be in connexion with another matter,the opportunity may be taken to mention here the importantachievement of the resolution of 7-6 : 6'-dinitrodiphenic acid (V)into optically active component^.^The resolution was carried out with the aid of brucine, and theacid from the less soluble salt had [.ID = + 225" and exhibited atendency to racernise.The significant feature which distinguishesthis example of enantiomorphism from all others is, of course, thatthe cause of the asymmetry must be sought in some property of thenucleus. The authors point out that their results may be explainedon the basis of alternative hypotheses, and the one which isapparently favoured is that the two nuclei are not coplanar. Inother words, Kaufler's diphenyl configuration or some modificationPresidential Address to the Physical Society, PTOC. Phya. Soc., 1921, 34,33.Sir William Bragg, T., 1922,121, 2783.H. G. Derx, Rec. trav. chirn., 1922, 41, 312; A., i, 651.G. H. Christie and J. Kenner, T., 1922, 121, 614.lo Compare Ann. Reprte, 1921, p. 8890 ANNUAL REPORTS ON THE PROGRESS OF CHENISTRY.of this is indicated.Indeed the support which Cain’s work in thediphenyl series lent to Kaufler’s view led to the prediction nowverified, that certain members of the group might be resolvable.llIf this explanation is accepted, and it appears reasonable from everypoint of view, it follows that the bond connecting the two phenylnuclei is not in the plane of either of the benzene rings l2 and thisis most ettsily understood on the basis of the benzene configurationdeduced by Bragg. But it may be pointed out that the juxta-position of two benzene rings in diphenyl and its derivatives is insome respects analogous to the packing of isolated molecules in thecrystals and might conceivably have a similar effect in dampingvibrations.0 rientation.The fact that m-nitrotoluene gives as one product of nitration2 : 3 : 6-trinitrotoluene is of interest since, in this case, the nitroxylenters every possible position o- and p - to the methyl group butapparently not at all m- to the nitro-group.13 It is remarkable thato-methoxybenzoic acid should yield, on nitration, along with thenormal products, no less than 27 per cent.of 4-nitro-2-methosy-benzoic acid (1),14 because whilst m-directive groups are almostalways also o-directive, it is very rarely that substitution in them-position occurs with respect to a pronouncedly o-p-directive group.One of the very few instances on record may now be deleted from theliterature, since it has been found that the acid obtained by Griessby the nitration of m-hydroxybenzoic acid and regarded by him asthe 5-nitro-acid (11) is in reality 6-nitro-m-hydroxybenzoic acid andsubstitution occurs exclusively in the o- and p-positions with respectto hydroxyl.It is interesting that chlorination occurs in positions2 and 6 but bromination leads only to the formation of 4-bromo-m-hydroxybenzoic acid.15 In the nitration of nitroacetotoluidides,two instances have been recorded in which the presence or absenceof sulphuric acid very greatly influences the position taken up bythe entering substituent.11 H. King, P., 1914, 30, 250; J. F. Thorpe, T., 1921, 119, 535.l2 J. Kenner, Nature, 1922, 109, 681; A., i, 533.lS 0. L. Brady, T., 1922, 121, 328.l4 V. Froelicher and J. B. Cohen, ibid., 1652.16 P. H. Beyer, Rec.trav. chim., 1921, 40, 621; A., i, 37ORGANIC CHEMISTRY. 91In the following scheme, the main products are indicated.Me Me MeNO,()NHACNO2Me Me MeIn sulphonation of naphthols and naphthylamines the apparentlyperplexing results can readily be collated with the orientation rulesdeveloped in the benzene series if certain of the peculiarities ofnaphthalene, such as the reactivity of hydrogen atoms in thea-positions, are taken into account. Thus, by analogy with phenol,the points of attack in @-naphthol should be positions 1, 3, 6, and 8,and these are the positions occupied by sulphonic radicles in thewell-known, technically useful acids prepared by direct sulphonation.It is now shown that bromination of @-naphthol leads to the 1-,1 : 6-, 1 : 3 : 6-, and 1 : 3 : 4 : 6-bromo-deri~atives.~~ The formationof the last substance involves attack of position 4, which is m- tohydroxyl, but it is also o-p- to bromine, so that the result is notsurprising.Reactions aiad Preparative Methods.Redzcction.-Stereoisomexic cyclohexanetriols are obtained fromeach of the three trihydroxybenzenes by catalytic reduction inaqueous or alcoholic solution at 140" under pressure.The catalystused is nickel.l* The usefulness of Rosenmund's process for thepreparation of aldehydes by catalytic reduction of acid chloridesis well illustrated by the preparation of gallaldehyde in quantityby way of its triacetate,20 and the method has also been success-fully applied to a number of chlorides of dibasic acids, for example,isophthalyl and terephthalyl chlorides.21 The reduction of nitro-benzene in neutral media by means of hydrogen in presence ofl6 0.1,. B d y , J. N. E. Day, and W. J. W. Rolt, F., 1922,121,526.1' J. Scott and R. Robinson, ibid., 844.1% H. Framen and G. Stiuble, J . p. Chem., 1921, [ii], 103, 362; A., i, 450.l9 J . 2:. Senderens and J. Aboulenc, Compt. rend., 1922, 174, 616; A., i,2o K . TIr. Rosenmund and E. Pfannkuch, Ber., 1922, 55, [B], 2357; A., i, .*l I<. JV. Rosenmund, F. Zetzsche, and C. Fliitsch, ibid., 1921, 54, [B],337.1030.2888; A., i, 3992 ANNUAL REPORTS OF THE PROGRESS OF CHEMISTRY.palladised animal charcoal a t the ordinary temperature leads to theproduction of p-phenylhydroxylamine in a yield of 80 per cent.22Ammonium sulphite has been recommended as a reducing agentapplicable to the preparation of arylhydrztzines, particularly thosecontaining nitro-groups, from related diazonium salts .%Nitration.-Quite a novel nitrating agent has been found inanhydrous pyridinium nitrate, applied in presence of excess ofpyridine.Naphthalene yields a-nitronaphthalene (40 per cent.),and anthracene yields 9-nitroanthracene (70 per cent.), whentreated in this manner.24 The nitration of quinol dibenzoatenever yields a mononitro-derivative but instead 2 : 6-dinitroquinoldinitrobenzoate. When, however, 2-nitroquinol dibenzoate wasobtained by another process, it was found to be impossible to intro-duce a second nitroxyl into the quinol nucleus. This interestingobservation can only be explained by the abnormal reactivity of amolecule a t the moment of its formation.25Halogenation.-A very powerful chlorinating agent is producedin a mixture of sulphur monochloride and sulphuryl chloride by theaddition of anhydrous aluminium chloride and appears to be analuminium sulphur chloride of the composition, A12S,C18.Inconjunction with sulphuryl chloride, this substance readily changesc hlor o b enzene into andhexachlorobenzene in successive stages.26 An investigation of theproducts formed by the chlorination of benzoyl chloride in presenceof anhydrous ferric chloride has shown that the percentages of theisomerides obtained are o- 14.5, m- 83.5, p - 2.0, and details aregiven of the preparation of pure m-chlorobenzoic acid by thismethod.27 Important advances from the preparative point ofview have also resulted from a research on the chlorination of thethree toluoyl chlorides at temperatures varying from 160-240°.25In this case, substitution naturally occurs in the methyl group andsubstances of the typesdic hlor o b enzenes , t e tr achlor o b enzene ,are obtained in good yield.The o-, m-, and p-w-dichlorotoluoyl2a I(. Brand rtnd J. Steiner, Ber., 1922,55, [BJ, 875; A., i, 536.23 W. Davies, T., 1922,121, 715.34 M. Battegay and Ph. Brandt, BUZZ. SOC. chim., 1922, [iv], 81, 910; A., i,25 F. Kehrmann, M. Sandoz, and R. Monnier, HeZu. Chim. Acta, 1921, 4,28 0. Silberrad, T., 1922,121, 1015.27 E. Hope and G. 0. Riley, ibid., 2510.28 W.Davies and W. H. Perkin, ibid., 2202.1001.941 ; A., i, 33ORQANJC CHEMISTRY. 93chlorides on digestion with milk of lime or chalk in an inertatmosphere yield the three phthalaldehydic acids in a pure con-dition, and this is the simplest method of preparation of thesevaluable substances. Somewhat unexpectedly it was foundpossible to hydrolyse the three o-trichlorotoluoyl chlorides by care-ful treatment with formic acid and so t o obtain the o-, m-, andp - o - tric hlorotoluic acids, CCl,* C,H,*C O,H, which are relativelystable, crystalline substances.AZEyEation.-cycZoHexanol may be converted into a stereoisornerideof the known 2-methylcycZohexanol (obtained by catalytic reductionof o-cresol) by conversion into cyclohesene, oxidation of the latterby means of perbenzoic acid in chloroform solution with productionof the oxide, and finally by the action of magnesium methyl iodideon Ohis substance.2gCH*OK CH--0 CH=OH/\\/CH,7H2 YHMe/\ /\/\/ \/( 3 3 2 CH2y327H2 * p 2 yH *CH, CH, CH, CH, CH, CII,Another ingenious alkylation process is illustrated by the prepar-ation of P-phenyl-aa-dimethylpropionic acid from p-phenylpropionicacid. This substance is first converted into a-hydrindone byKipping's method, and the ketone alkylated by means of sodamideand methyl iodide.The product is 2 : 2-dimethylindan-l-one (I}and this may be decomposed byamide'of the desired acid (11).(1.1 I I CMe,/\AH,\\/\co/sodamide wiDh formation of the"CH,*CMe,*CO*NH, I 1 (II.'\/generally applicable to an acidR'*CH,*COCl, R'*CH,*COPh,The process is rendered moreR'*CH2*C02H by the stagesR'*CR,*COPh, Rf*CR2*CO*NH2.so On heating ethylene chloro-hydrin with toluene-p-sulphnyl chloride, P-chloroethyl toluene-p-sulphonate, C,H,Me*S02*O-CH2*CH,C1, is obtained in a yield ofmore than 90 per cent.This ester is a valuable agent for theintroduction of the chloroethyl group into phenols and aminea.The method is far more convenient and gives much better yieldsthan those depending on the use of ethylene halide~.~lCondensations.-The use of sulphoacetic acid, prepared by29 M. Godchot and P. BBdos, Compt. rend., 1922,174, 461; A,, i, 334.30 A. Haller and E. Bauer, Ann. Chim., 1921, [ix], 16, 340; A., i, 258.31 G. R. Clemo and W.H. Perkin, T., 1922,121, 64294 ANNUAL REPORTS ON THE PROGRESS OF OHEMISTRY.mixing acetic anhydride and sulphuric acid, as a synthetical agentcontinues to give results of interest. Under specified conditions,guaiacol may be converted by this reagent int'o acetylisoaceto-vanillone ( 111),32 whilst pyrogallol 1 : %dimethyl et,her is acetylatedin the nucleus even when it is heated with acetic anhydride and afew drops of sulphuric acid. In this case, the product is 3-acetoxy-2 : 4-dimethoxyacetophenone (IV).=OMe OMe(111.) (jO.cOMe\COMeIt is generally believed that the mechanism of substitution in thearomatic series comprises two main stages; an addition and then afission of the additive product. The second reaction is, however,usually so rapid that the initial phases of the process are difficultto recognise, although this is not invariably the case.In the olefineseries, the addition is more facile and the fission more difficult thanin the aromatic series. Advantage has been taken of this circum-stance in connexion with some experiments on the mechanism of theFriedel-Crafts' reaction. It has been shown that, under the influenceof a,luminium chloride, acetyl chloride unites with cycEohexenewith the production of 2-chlorocyclohexyl methyl ketone (V), whichis isolable and convertible by the further action of aluminiumchloride in carbon disulphide solution into tetrahydroacetophenone(~11.34The function of the aluminium chloride is identical in bothstages and is considered to be concerned with the weakening ofthe link between carbon and chlorine.A peculiar application ofthe catalytic activity of aluminium chloride is the elimination ofhydrogen from aromatic nuclei. This is always effected in presenceof nitrobenzene, which exercises a specific influence. The bestknown examples are the syntheses of complex polynuclear compoundsdue to Scholl and his collaborators, for example, that of pyranthrone32 W. Schneider and E. &aft, Ber., 1922, 55, [B], 1892; A., i, 750.3s I(. Braad slnd H. Collischon, J. pr. Chern., 1921, [ii], 103, 3203 A., i,94 H. Wieland and L. Bettag, Ber., 1922,5S, [B], 2246; A,, i, 1033.452ORGANIC CHEMISTRY. 95from dibenzoylpyrene by intramolecular condensation. Thereaction is capricious in its vagaries, but has now been applied tocertain simple compounds. Thus benzil yields phenanthraquinone(25 per cent.) and a-naphthyl ethyl ether yields 4 : 4'-diethoxy-1 : 1'-dinaphthyl (70 per cent.).35 Attempts have been made toreplace the nitrobenzene by azobenzene, but this is not possible inmost cases.Aminodiphenyl is obtained, however, in a yield of70-80 per cent. by the regulated action of aluminium chloride at60" on a mixture of benzene and a~obenzene.~~ The explanationadvanced includes four stages, which are summed up in the equationPhKNPh + 2C6H6 = 2C6H4Ph*NH2.On account of the excellent yields and the relation of the productsto naturally occurring compounds the synthesis of p-keto-basesfrom ketones, formaldehyde, and amine salts is noteworthy.Atypical instance is afforded by the preparation of o-dimethyl-aminopropiophenone, obtained as its hydrochloride by heatingtogether equivalent quantities of acetophenone, paraf ormaldehyde,and dimethylamine hydrochloride in concentrated alcoholic solution :COPhMe + CH,O + NHMe, --+ COPh*CH2*CH2-NMez.37Molecular Rearrangements.Admittedly the allocation of specific configurations to stereo-isomeric oximes rests on a slender foundation, and one of thesign-posts has, it now appears, been turned in the wrong direction.The unwarranted assumption that in the Beckmann change groupsin a cis-position are transposed has been proved to be erroneous byJ. Mei~enheimer.~~ 3 : 4 : 5-Triphenylisooxazole (I) is oxidised bychromic acid, or by ozone, with formation of benzoyl-p-benzil-monoxime (11).PhE (11.)N*OBzThis independent and probably trustworthy determination ofconfiguration involves the alteration of the formulx?, a t presentaccepted, o€ the dioximes of benzil; the a-dioxime is I11 and the@-modification is IV, no change being required in regard to theY- varietv .s6 R.Scholl and G. Schwarzer, Ben, 1222, 55, [BJ, 324; A., i, 331; R.36 R. Pummerer and J. Binapfl, &id., 1921, 54, [B], 2768; A., i, 24.37 C. Mannich and G. Heilner, ibid., 1922, 55, [BJ, 356; A., i, 351;38 Ibid., 1921, 54, B], 3206; A., i, 15%Scholl and C. Seer, ibid., 330; A., i, 336.C. Mannich and D. Lammering, ibid., 351096 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.These corrections should be noted by writers of text-books andconstitute an excellent example of the prudence of employing non-committal prefixes to distinguish stereoisomerides.The Beckmanntransformation must now be represented as occurring in accordancewith the scheme :In continuance of earlier work, a comparative study has beenmade of the " semibenzene " hydrocarbons and their aromaticis~merides.~~ The semibenzenes have the lower densities and thehigher molecular refractions and dispersions. The simplest memberof the series is 1 : 1-dimethyl-4-methylene-A2: 5- cyclohexadiene (V),which passes very readily into +-cumene (VI), with development ofheat, when a drop of hydrochloric acid is added to its solution inacetic acid.Me(V. 1 Me,/=\=CH, Me/-\Me (VI. ) \=/ \-/This transfer of the alkyl group to the adjacent carbon atomrepresents the normal occurrence, but instances of migration tothe meta-position are not lacking.Thus the semibenzene VII ischanged by warming with a mixture of acetic and sulphuric acidsinto pentamethylbenzene (IX). The possibility might be queriedthat this is a double migration through the intermediate stage VIIIor a related hydrated compound.Me Me2 Me Me- \=/ \-/ MY Me MeW I . 1 (VIII. ) (IX. 1Me,, /=\- /-CH2 CH2-/-7\Me Ble/-\MeIn the transformation of methylaniline hydrochloride intop-toluidine hydrochloride the main factor is found to be the temper-ature employed, and the course of the change is but little affectedby the addition of salts such as zinc chloride or aluminium chloride.At 310°, there i s notable production of dimethylaniline, and thistends to confirm the view that the migration is due to successivereactions, the methylaniline hydrochloride decomposing into anilineand methyl chloride, which react with formation of the originalsubstances (reversible), of dimet hylaniline (reversible), and ofas K.von Auwers and K. Ziegler, Anwlen, 1921,425, 217; A., i, 119ORGANIO OHEMISTRY. 97p-toluidine (irreversible).m A long paper 41 has been published byP. Jacobsen describing further developments of his exhaustiveinvestigations of the isomeric changes of hydrazo-compounds. Onthe whole, the results resemble those with which we are alreadyfamiliar, but the following points may be mentioned. If an ortho-position is free, di-p-substituted hydrazobenzenes yield o-semidineswhich, in case the substituents are different, have one of twoformde as indicated below :NH2/-\NH/-\R' w L/NH2R<=NH.NH/\ZI)R' / RIn no instance were both possible o-semidines isolated.If theconvention is adopted that the amino-group of the semidine occursin the p-position to that one of the two p-substituents in the hydrazo-compound which has the greater " directing power " in the trans-formation, then, of all the groups examined, ethoxyl is the mostpowerful and methyl comes next in order. When R is acetoxyl,a p-semidine is formed by displacement of the group; thus 4'-acetoxy-4-methylhydrazobenzene (X) yields the o-semidine (XI)and the p-semidine (XII).NH2aLJNH\-/ /-\ -/-\OH A_.-- (XI.)(X.1 Me/7NH*NH/\30.COMe \-/ MeThis extrusion of oxygen, directly united to the aromatic nucleus,is a very rare phenomenon.No example of the o-benzicline changewas encountered in the benzene series, but its occurrence in thenaphthalene group was confirmed. The following comparisonis interesting :r\NH-NHc>NHA~ W -+ NH2/aNH<I>NHAc,NHAc/-\NH*NH/-\NHAc -+ NH2/-\NB/-\Me . \-/ \-/ \-/ \-/Me Me Me NH240 E. E5eckma.m and E. Correns, Ber., 1922, 65, [B], 852; A., i, 535.4l Annalen, 1922, 427, 142; A., i, 589.REP.-VOL. XIX. 98 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.In the second case figured, the p-semidine is also formed but invery small relative amount. Migration of a benzoyl group is provcdto occur in the course of the synthesis of benzoylmethylenedioxy-benzoin by the action of an alcoholic solution of sodium ethoxideon a mixture of benzoylmandelonitrile and piperonal : 42CHPh( OBz)*CN+ CHO*C,H,:O,CH, -f COPh*CH( OBz)*C6H3:02CH2.This confirms Lapworth’s theory that the production of benzoinin the usual manner depends fundamentally on the aldol-likecondensation of berizaldehyde and mandelonitrile.Reactivity of Halogen Atoms in Carbon Compounds.The reactivity of halogen is of two main types which may coexistbut.,are exhibited to an unequal degrcc in any one compound.Theatom is in some cases readily replaced by such groups as -OH,NH,, and in other instances it is essentially reducible and oxidising.The extreme hydrolysable type is represented by chlorine in theacid chlorides. This, it should be noted, is also reducible under thecorrect conditions, but the reaction is far from being as characteristicas that of replacement by hydroxyl.The reducible type is foundin the hypochlorites, in substances containing the group -NCl-such as the N-chlorosulphonamides, and in aa-dihalogenated p-di-ketones. In these cases replacement of the halogen by hydroxylis still possible, but is often a very difficult operation. Adherentsof the various brands of polarity theories speak of the halogen asnegative or positive and this is a t least a useful classification of awide range of phenomena. It is perhaps a little more accurateand certainly more non-committal to regard the atom to whichthe halogen is attached as positive and negative respectively. Avery interesting series of observations has been made on the in-fluence of substituents in the benzene ring on the mobility of chlorinein the shortest side chain.43 The reaction measured was thehydrolysis of the various benzyl chlorides and the influence of thegroups was found to be in the order : p-Me>o-Me>m-Me>H>Now the groups Me, H, C1, NO, represent a descending series inregard to the electropositive character of the constituent atoms andthe results show that, independent of the position of the substituent,the more electropositive is the molecule the quicker is the hydrolysis.This is an example of the genera2 polar effect, the direction of whichis explained by the consideration that the reaction is fundamentally,under the conditions employed, an attack on the molecule by42 H.Greene and R. Robinson, T., 1922,121,2182.a S. C. J. Olivier, Rec. trav. chim., 1922, 41, 301; A., i, 646.P-CI 7 0-C1 > m-CI > m-NO2 > o-NO~ > P-NO~ORGANIC CHEMISTRY. 99negative hydroxyl ions. In a similar investigation of the speed ofsynthesis of sulphones by the condensation of benzene with sub-stituted benzenesulphonyl chlorides, the series was expanded to :Me > H > I > Br > C1> NO,. But on comparing the effect of positionof the substituent on the reactivity, it will be seen that -CH,and C1- exercise their greatest influence from the p - and o-positions,whilst m-NO,-benzyl chloride is more reactive than its isomerides.This rcversal in passing from groups which are negative on the basisof the theory of alternating polarity, to a group which, on the samegrounds, must be considered positive is in agreement with the workof Lspworth and Shoesmith (see below) and the whole researchthrows some light on the relative importance to be attached to thegeneral and alternate polar effects.. If the methoxy-compoundshad been included in the series, there is little doubt that 0- andespecially p-methoxybenzyl chloride would have proved the mostreactive of the substances investigated. This is to be expectedbecause there is strong evidence that methoxyl is conjugated withthe nucleus, tt, circumstance which allows the alternate effect tooverpower the general effect and throws such groups as methoxyland amino out of their natural order.If the correlation of thetwo types of reactivity of halogen with polarity effects is wellfounded, then it must follow that positional influences whichfacilitate hydrolysis of alkyl or aryl halides will render reductionmore difficult and vice versa. Again, the general effect must beeliminated by comparing isomerides only. Such a comparison hasbeen made of the three methoxybenzyl bromides and the resultsare in excellent agreement with the theory.44 The effect of thenegative methoxyl group on the bromine atom is illustrated in thefollowing expressions, in which the signs have a purely relativesignificance :+'\-6H,-& Me0 -/\-- + +, CH,-Br '?-&H2-Gr.\;!Me \/ Me6</It will be seen that in the 0- and p-compounds the result is toenhance the natural polarity of the bromine, whereas the reverseis the case in m-methoxybenzyl bromide.Therefore 0- and p -methoxybenzyl bromides should be more readily hydrolysed thanthe m-isomeride, a i d this was found to be the case to a very strikingextent. Numerous examples of the high reactivity of bromine in aside chain p - to methoxyl were, however, already known and thesecond part of the prediction, that the m-methoxybenzyl bromide** A. Lapworth and J. B. Shoesmith, T., 1922,121, 1391.E 100 ANNUAL REPORTS ON TBE PROGRXSS OF CHEMISTRY.should be found to contain the more reducible halogen, is thereforeall the more valuable as a test of the hypothesis because it couldnot have been made by analogy with known reactions and withoutconsiderations based on induced polarities.Experiments on thcreduction of the rnethoxybenzyl bromides with hydrogen iodideshowed that actually the m-derivative was the most readily attacked.This double verification of anticipated effects is not to be neglectedin assessing the value of the theory in connexion with the problemsof reactivity and mechanism of reactions. Halogen atonis in theo- or p-positions with respect to a strongly negative atom or groupin the aromatic nucleus should evince positive polar character andthis has already been shown by numerous investigators to be thecase so far as reducibility is concerned. Additional evidence issupplied by the behaviour of certain iodinated benzene derivative^.^^3-Iodo-p-toluidine, p-iodoaniline, and 3-iodo-p-hydroxybenzoicacid are decomposed by boiling with 10 pcr cent.hydrochloric acidin such a may that the iodine is partly replaced by hydrogen and incoinpensation there is production of di- and tri-iodo-derivatives.Aceto-3-bromo-p-toluidide behaves in a similar manner. Thissubstituting action in presence of acids is typical of the behaviourof positive halogen and is presumably due to elimination in the formhal(OH), as the result of the union of the negative carbon atom, orother atom to which the halogen is attached, with a hydrogen ion.Some significant examples have been previously recorded andperhaps the most interesting in the aromatic series is the formation of3-bromo-2-aminoanthraquinone either by heating 1-bromo-2-amino-anthraquinone alone or a mixture of 2-aminoanthraquinone with1 : 3-dibromo-2-aminoanthraquinone. The former reaction is themigration of bromine to a more stable position in the molecule andmay be compared with the well-known change of ethyl cr-bromo-acetoacetate into ethyl y-bromoacetoacetate which occurs inpresence of traces of hydrobromic acid.46 The simplest explanation4'takes cognisance of the highly positive character of the bromineatom in the a-position, where it is under the influence of both thecarbonyl and carbethoxyl groups, and involves the stages :CH3*CO*CHBr*C0,Et + HBr+ -CH3*CO*CH,=C0,Et + Br, -+CH,Br*CO*CH,-C0,Et + HBr.An alternative mechanism which has been suggested48 is the45 B.H. Nicolet, J . Amer. Chem. Soc., 1921, 43, 2081; A., i, 121.46 A. Hantzsch, Ber., 1894, 2'7, 356, 3168 ; M. Conrad, ibid., 1896,29, 1042.4 7 A. Lapworth, Mem. Mancheater Phil. SOC., 1920, 64, ii, 8.46 G. T. Morgan and H. D. K. Drew, T., 1922,121, 928.following ORGANIC CHEMISTRY. 101This is untenable because in the similar rearrangement ofethyl a-bromomethylacetoacetate, CH,*CO*CMeBr*CO,Et +CH,Br*CO*CHMe*CO,Et, the scheme involves transference of methylas well as of bromine and the product should then have the con-stitution CHBrMe*CO*CH,*CO,Et, which does not appear to bethe ~ase.~S There is no very cogent reason for supposing that sub-stitutions by positive halogen must always depend on successivereactions and on the intervention of acids.Thus Wohl has shownthat acetobromoamide is a useful brominating agent and he regardsthe reaction as occurring directly between the molecules concernedand involving the interchange of hydrogen and bromine.50 Onthe other hand, an ingenious process of regulated chlorination bymeans of N-chloroacetanilide and hydrochloric acid in small butdefinite concentration is based on a directly contrary assumption. 51The two views are not irreconcilable nor in any way contradictoryand both are entertained by Orton in connexion with differentmigration phenomena. Thus the direct substitution is analogous tmothe transformation of phenylnitroamine into o-nitroaniline and theindirect to the conversion of the N-chloroacetanilides into thenuclear-substituted isomerides.In order to avoid the formationof hydrobromic acid in the course of bromination, it is now proposed 52to employ dibromodimethyldihydroresorcinol as a brominatingagent. This substance is reduced with uncommon ease and evenby the action of dilute aqueous sodiuni hydroxide. It reactsquantitativcly with dimethylaniline in the following sense :As the enolic monobromo-derivative can bc recovered and usedagain, the method may have practical value. Gupta and Thorpedo not adopt the view that the reactivity of the bromine exhibitedin this reaction is due to its positive polar character, but prefer tlichypothesis that the bromine is mobile because it inhibits a tautomericprocess involving the keto-groups.There is a tendency to acquire49 M. Conrad and A. Kreichgauer, Ber., 1S96, 29, 1042.61 K. J. P. OrtonandH. King, T., 1911,99, 1185.Bz B. M. Gupta and J. F. Thorpe, ibid., 1922,121, 1896.Ibid., 1919, 52, [B], 51102 ANNUAL REPORTS ON TEE PROGRESS OF CHEMISTRY.a hydrogen atom necessary for tautomerism, and earlier examples ofthe application of this theory will be recalled. In the Reporter'sopinion, both views are correct and are reconciled by the consider-ation that the system acquires its hydrogen atom by union of thelatter with oxygen so that an enol is the first product. Thus thefundamenOa1 factor is the affinity of oxygen for hydrogen and fewchemists will find it m c u l t to equate this with the negativeelectrochemical character of oxygen and the positive character ofhydrogen. The hydrogen is probably acquired as a proton whichattaches itself to the free electrons of the oxygen octets; the rnole-cule thus becomes positively charged and recovers neutrality byreversing the process, acquiring an electron (po tassiobenzophenone ? )or as an important alternative by ejecting some other atom in apositively charged condition.In keto-enol tautomerism catalysedby hydrogen ions, we have the stages :This may be compared with the following scheme in which theatom liberated is Br +, that is to say, bromine in a, form whichcould combine with a hydroxyl ion to form hypobromous acid :I + - + -I + I + @ O=C-C-Br --.+ @-----Ozec.----Br--- ---+ H-O-('j=C BrI I I I I IThe tendency towards a more even distribution of valency is thedriving force in the reaction and this is carried into effect by aprocess of conjugation, using that term in its wider meaning ofre-distribution of affinity through a chain of atoms.On thisinterpretation it is seen that " the tendency to acquire a hydrogenatom necessary for tautomerism " is a phrase which accuratelyrepresents the phenomenon and is not at all inconsistent with theview that the bromine exhibits positive polarity. In any particularcase of double decomposition, the actual charges mentioned aboveneed not be acquired, because the interchange of hydrogen andbromine will be synchronous. Probably too, both oxygen atomsin the diketone attract the hydrogen and this can easily berepresented with the aid of partial valencies.It should beemphasised that the alternate labelling of atoms in a chain with + and - signs is never intended to indicate the mechanism of theeffect, which, as in the example under discussion, is often the resultof conjugation. Further interesting substitution reactions due topositive halogen have been encountered in a study of the actionof nitrogen trichloride on aromatic hydrocarbon^.^^ Toluene is6s G. H. Coleman and W. A. Noyes, J . Amer. C h m . SOC., 1921, 43, 2211 ;A., i, 133ORGANIC CHEMISTRY. 103converted into benzyl chloride, monochlorotoluenes, and morehighly chlorinated compounds. At the same time, some N-chloro-aminotoluene derivatives are formed. Bromotrinitromethane con-tains a highly positive bromine atom and in aqueous hydrobromicacid solution is able to change phenol into its tribromo-derivative.54Reduction by titanous salts and oxidation of hydrazine withformation of nitrogen have been applied as tests for positive halogen,and an extensive comparative study of the effect of constitution onthe property has been made.55 The results are in very good agree-ment with the theory of induced alternate polarities of atoms in achain, although some few details connected with degree of reactivityare not yet satisfactorily explained. This is not surprising, and itshould be stated that, on account of the complexity of the factorswhich control the speed of reactions, the polarity theory cannot besuccessfully used to interpret relative reaction velocities except incarefully chosen cases.The chief necessary precautions are theavoidance of cases where the general polar effect and steric con-siderations are likely to be of importance and it k also desirablethat the mechanism of the reaction should be known to a firstapproximation. One of the anomalous observations noted aboveis that dichloroacetylacetone, COMe*CCI,*COMe, does not oxidisehydrazine under the specified conditions, whereas ethyl dichloro-malonate, CCl,(CO,Et),, readily does so. The explanation given isbased on the larger number of key oxygen atoms in the lattersubstance, but this leads to inconsistencies, as pointed but by Guptaand Thorpe (loc. cit.), and indeed carbonyl is universally regardedas a more activating group than carbethoxyl.Triphenylmethyl and Related Subjects.The electrical conductivity of solutions of triarylmethyl bromidesin sulphur dioxide or hydrocyanic acid is comparable with that ofaqueous solutions of potassium hydroxide and shows little variationamong individuals.The molecular conductivities of the chlorides,however, are not so high and diphenyl- a-naphthylmethyl chlorideis a better conductor than diphenyl- p-naphthylmethyl chloride andthis again than triphenylmethyl chloride. The order is that of theease of dissociation of the corresponding hexa-arylethanes into thefree radicles and also of the conductivity of the free radicles them-selves. Diphenyl- p-naphthylmethyl is obtained in the usualmanner and the hexa-arylmethane, a pale yellow, crystalline powder,64 T.Henderson and A. K. Macbeth, T., 1922,121, 892.65 Henderson and Macbeth, Zoc. cit.; E. L. Hirst and A. K. Macbeth,T., 1922,121, 904, 2169; H. Graham and A. K. Macbeth, ibid., 1109; A, K,Macbeth, ibid., 1116104 ANNUAL REPORTS ON TEE PROGRESS OF CHEMISTRY.m. p. 135-140", is found by the cryoscopic method to be dissociatedfrom 15 to 50 per cent. in eight solvents ranging in freezing pointfrom -22" to + 80'. The changes in colour of solutions of thissubstance due to alterations in concentration and temperature areby no means parallel to the changes in extent of dissociation. Thisshows that the equilibrium system is more complex than has oftenbeen assumed. It is suggested that in addition to dissociation thereis also tautomerisation of the benzenoid radicle into a quinonoidm~dification.~~ It is perhaps well to note at this point that althoughto crystalline substances are now often given the names of the radiclesproduced in solution, the relation between the two states remainshighly problematical.An interesting contribution to the subjectis concerned with the preparation of penta~henylethyl.~' Sodiumtriphenylmethyl in ethereal solution is treated with benzophenonechloride, the containing vessel being filled with nitrogen. Theproducts are pentaphenylethyl and triphenylmethyl and on con-centration of the filtered liquid the former separates in coarse crystalsand can be largely mechanically separated from the hexaphenyl-ethane by swirling and decantation and completely by washing withether .2Ph3CNa + CBh,Cl, = Ph,C*CPh, + Ph3C + 2NaC1.Pentaphenylethyl forms golden-yellow crystals with a metallicglance and is almost entirely unimolecular in solution.Triphenyl-biphenylene-ethyl, Ph3C*bc6H4*c6H,, is similarly prepared fromsodium triphenylmethyl and fluorenone chloride. It occurs inlarge, violet prisms and is wholly unimolecular in solution. Thecourse of the decoinposition of pheny1a.zotriphenylmethane and ofsubstituted derivatives has been examined with the object ofdetermining whether free radicles are formed in the process orThus the production of tetraphenylmethane (Gomberg) mightproceed according to the alternative schemes :(A) Ph*N=NCPh, + Ph* + NZ + *CPh,Ph* + GPh, + CPh,Ph---CPh,(B) Ph*N=N*CPh, -+ i i -+ Ph*CPh, + N,&-=-NActually it was found that triphenylmethyl was produced andcould be recognised spectroscopically, by colour changes in hotand cold solution and by the formation of the peroxide.Thephenyl radicle, presumably formed at the same time, combines with56 M. Gomberg and F. W. Sullivan, jun., J. Amer. Chem. SOC., 1922, 44,1810; A., i, 929.57 W. Schlenk and H. Mark, Ber., 1922, 56, [B], 2285, 2299; A., i, 1002.5 * H. Wieland, E. Popper, and H. Seefried, ibid., 1816; A., i, 772ORGANIC CHEMISTRY. 105hydrogen, but the oxidised component thus necessitated has notyet been recognised. This proves beyond doubt that the azo-compound decomposes with formation of radicles, but it is notlogically compulsory to proceed a further step and assume that thetetraphenylmethane formed owes its existence to the operation ofscheme A rather than of scheme B.The application of the newmethod of preparation of triphenylmethyl to the radicles of the basictriphenylmethane dyes is of great interest. It was found, forinstance, that phenylazobis-p-dimethylaminotriphenylmethane,NPh:N*CPh( C6H4*NMe,),, yields on decomposition, benzene, nitro-gen, and bis-p- dimet h ylaminotriphenylmethyl, CPh ( C6H4*NMe2) 2,which is the radicle of malachite green. This unstable substanceand tri-p-dirnethylaminotriphenylmethyl, C( C6H4*NMe2),, the radicleof crystal violet, are scarcely more coloured than triphenylmethylitself. The observation is interpreted as supporting the quinonoidtheory of the structure of the ions of the basic dyestuffs of thetriphenylmethane group and it would certainly seem to exclude theRosenstiehl formula, and Baeyer’s ionisable bond modification ofthis, in a more definite way than has previously been possible.From the point of view of rational classification a t least, the papers 59which Hantzsch has published during the year bearing on therelated subjects of the constitution of carbonium salts, halochrom-ism, and solvatochromism, and on the theory of triphenylmethanederivatives contain much that is of value even though, as more thanone author claims, many of his suggestions have been anticipated.The lamentable position into which organic chemistry threatena todrift is that there will be as many theoretical systems as theorists,and it is matter for congratulation when several chemists inde-pendently arrive a t somewhat similar conclusions.It would beimpossible to give an adequate exposition of Hantzsch’s system inthis place, but it may be well to refer to one matter. Only two typesof triphenylmethane derivatives are recognised, the colourless non-conduct’ing variety and the coloured conducting, true carboniumcompounds in which carbon has normally the co-ordination number3. Both types are present in the equilibrated system : Br*CPh3 e[CPh,]Br, which may be shifted to the right by the introduction ofsubstances which readily form complex anions with the bromine.But, on the other hand, triphenylmethyl may also function as ananion in such substances as Na[CPh,], which are also coloured.This conception of triphenylmethyl as an amphoteric ion leadsnaturally to the suspicion that the coloured hexa-arylethanes arealso complex compounds having the formula [Ar,C][Ar,C].A.Hantzsch, Ber., 1921, 54, [B], 2573, 2613, 2620, 2627; 1922, 55, fB],953; A., i, 24-26, 556.E’Compare also A., i, 331, 445106 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Carbinols containing phenylethinyl groups have been preparedand found to exhibit typical halochromism.60 For example,triphenylethinylcarbinol, (CPhlC)&*OH, is obtained by the actionof magnesium phenylethinyl bromide on phenylpropiolyl chloride.It gives a bluish-violet coloration with sulphuric acid, deep bluish-violet with perchloric acid, and bright blue with stannic chloride.The conclusion drawn is that the halochromy of triphenylcarbinolsis not to be associated with changes in the benzene rings, since thetypical phenomena can be reproduced when “ gap linkings ” areintroduced between the carbinol group and the nuclei.A numberof distinct investigations published during the year bear on thesame subject .61 Diphenylphenylethinylcarbinol is converted byacetyl chloride, acetic anhydride, and the like and by hydrogenchloride in ethereal solution into phenyl a-phenylstyryl ketone : 62CPhi C.CPh,*OH + COPh*CH:CPh,. That the arrangement ofcarbon atoms remains undisturbed (wandering of phenyl was apossibility) was proved by carrying out hhe transformation :CPhiC*C(C6H,C1),*OH + COPh*CH:C(C6H4C1), and oxidkingthe product to pp’-dichlorobenzophenone.The puzzling feature ofthe reaction is that it occurs so readily in the absence of water. Itmay be mentioned here that the fate of over-oxidised leuco-bases ofthe triphenylmethane dyestuffs has been ascertained. The gradualtreatment at the ordinary temperature of a moderately concentratedmalachite-green solution, acidified with sulphuric acid, with leadperoxide until a diluted sample shows no green tinge, followed byfiltration and addition of perchloric acid, precipitates orangeneedles of tetramethyldiphenoquinoneimonium perchlorate,The same perchlorate results from the oxidation of tetramethyl-benzidine or of Michler’s hydrol.Alicyclic Group.There is much overlapping of the subject matter of the sectionsof this report and numerous references to alicyclic compoundswill be found elsewhere. A synthesis of l-methylcyclopropane-l-carbosylic acid (I) has been carried through the followingF.Straw and A. Dutzmann, J. pr. Chem., 1921, [ii], 103, 1; A., i,148; K. Ziegler, Ber., 1921, 54, [B], 3003; A., i, 151; S. Skraup and L.Freundlich, ibid., 1022, 55, [B], 1073; A., i, 539; K. H. Meyer and K.Schuster, ibid., 815; A., i, 540.60 K. Hess and W. Weltzien, Ber., 1921, 54, [B], 2511; A., i, 35.62 Ibid., 819; A., i, 556.63 F. Kehrmann, G. Roy, and (Miss) M. Ramm, HeZu. Chim. Acta, 1922,5, 153 ; A., i, 467ORGANIC CHEMISTRY. 107stages : 64 Formaldehyde (2 mols.) and propaldehyde (1 mol.) are con-densed to dihydroxy-a cc-dimethylpropaldehyde, CHO*CMe(CH2*OH),,which is converted into its oxime and then by the action of aceticanhydride into diacetoxypivalonitrile. The latter, by heating withsaturated hydrobromic acid at 125-130" during twenty hours, yieldsdibromopivalic acid, CMe(CH2Br)2*C02H. Methyl dibromopivalatereacts with zinc dust in methyl alcoholic solution with formation ofmethyl 1 -methylcyclopropane- 1 -carboxylate.The isomeric hydrocarbons vinylcyclopropane (11) and methylene-cyclobutane (111) have each been produced by the decomposition ofsuitable quaternary ammonium compounds. 65 Acetylcyclopropane-oxime, FH2>CH*CMeXOH, is reduced to the amine, whichis fully methylated and the iodide converted to hydroxide.The distillation of this trimethyl- a- cydopropylethylammoniumCH2hydroxide, CH2>CH*CHMe*NMe3> OH, furnishes chiefly Vinyl-CH2cyclopropane and very little of the tertiary base.Methylenecyclo-butane is similarly prepared in small yield from cycZobutylmethy1-trimethylammonium hydroxide, CH,<g2>CH*CH2*NM%} OH,which, however, gives on decomposition cyclobutylmethyldimethyl-amine as the main product. The action of hypochlorous acid onmethylenecycZobutane gives rise to a chlorohydrin,CH2<gg:>C( OH)*CH2C1 or CH,<gEz> CC1*CH2*OH,the former being indicated by analogies. This is converted intocyclopentanone when it i s heated with litharge and water, whilstthe action of aqueous potassium hydroxide produces an oxide,CH2<CH2>C<XH2, which may be isomerised to cyclobutane-CH2aldehyde, CH,<CB2>CH-CH0, by the action of zinc chloride .66When campholcnic acid (IV) is treated with an aqueous solution ofcalcium hydroxide and with silver oxide a t 60", it is partly reducedto camphor and partly oxidised to a-Betocampholenic acid (V).67( - 3 3 264 M.Kohn and A. Mendelewitsch, Jfona&h., 1921, 42, 227; A., i, 518.N. J. Demjanov and (Miss) M. Dojarenko, Ber., 1922, 55, [B], 2718,2727; A., i, 1014, 996.6 6 Ibid., 2730; A., i. 1009.6 7 J. P. C. Chandrasena and C. K. Ingold, T'., 1922, 121, 1552.E* 108 ANNUAL REPORTS ON TEE PROGRESS OF CHEMISTRY.CHXMe CHXMe I XMe, & XMe,CH,*CH*CH,*CO,H H,*CH*CO-CO,H(N* 1 (V. 1 (VI* 1The yield of camphor obtained is stated to be small, but is notprecisely specified, so that it is difficult to form an independentopinion as to the significance of this very striking observation.Ifthe view put forward, that trans-dihydrocampholenic acid (VI) isthe intermediate stage, is correct, then we have another and apeculiar instance of the abnormal reactivity of a newly formedmolecule, because both cis- and trans-dihydrocampholenic acidshave been isolated by another investigator in their racemic formsand found to be perfectly stable substances.68 The condensationof chloral with methyl malonate leads to the formation of methyl0 : 3 : 3 - dicyclo - A1 - octene - 3 : 7 -&one - 2 : 4 : 6 : 8 - tetracarboxylate(VII), which can be converted by hydrolysis and reduction into thediketone (VIII), the glycol (IX), and finally into 0 : 3 : 3-dicyclo-octane (X).6gC(CO2Me)=7-- CH(C02Me)> CH2*CH*CH2>C0c0<CH(C02Me).CH*CH(C02Me) C0%H2*b€€*CH,(VII.) (VIII.)Tautome r i m .1 : 5-Dihydroxynaphthalene reacts with sodium hydrogensulphite to produce a compound, CloHlo0,S2Nn,, which, on boilingwith water, loses one molecular proportion of sodium hydrogensulphite and is changed to sodium 5-hydroxy-l-ketotetrahydro-naphthalene- 3 -sulphonate (I).2 : 7-Dih ydroxynap ht halene be -haves somewhat differently and gives the compound 11, which isconverted by dry ammonia a t 100" into a corresponding amino-derivative (111). The latter on decomposition with water yields7-amino-2-naphthol. 70P.Lipp, Ber., 1922, 55, [B], 1883; A., i, 735.G. Schroetor and G. Vossen, Annalen, 1922, 426, 1 ; A., i, 122.70 W. Fuchs and W. Stix, Ber., 1922,55, [B], 658; A,, i, 451ORGANIC CHEMISTRY. 109The series of reactions throws light on the mechanism of Bucherer'sprocess for the conversion of naphthols into naphthylamines, butit is surprising that it should also be claimed as a demonstration ofthe tautomerism of the dihydroxynaphthalenes. It has long beenthought that the a-diketones may exist in a peroxide form, andWillstatter's discovery of colourless and coloured modifications ofo-benzoquinone was interpreted in this way. Definite confirmationof the accuracy of the hypothesis is now provided by a carefulinvestigation of the benzils.'l Normally, these compounds are, ofcourse, yellow, but in certain cases they have been found to becolourless or almost so.The first example was discovered byJ. C. Irvine in 1907 when he prepared the colourless 2 : 2'-dimethoxy-bemil." The coloured benzils react readily with o-phenylenedi-amine with formation of quinoxalines and are readily oxidised byhydrogen peroxide to two molecules of substituted benzoic acids.The observation has now been made that the colourless benzilsexhibit neither of these reactions with facility. The colourlesscompounds often give pale yellow solutions, and this suggests theexistence of an equilibrium :R*Q=Q*R0-0 R*CO*CO*R =$=Yellow. cOlOU7'k%8.It is in fact found that the reactivity of a benzil is roughlyproportional to the intensity of colour of its solut'ion.Finally,in 4 : 4'-dibenzyloxybenzil, CH,Ph*O*C,H,*CO*CO*C6H4*O*CE12Ph(IV), a substance has been discovered which can be isolated inbright yellow diketonic and colourless peroxidic forms.The latter is obtained by quickly cooling a concentrated etherealsolution of the substance. It crystallises in colourless needleswhich become yellow a t 121' and melt indefinitely a t 124". Thisis the labile modification and if allowed to remain in contact withthe solvent passes into solution, whilst yellow prisms of the morestable diketonic form, melting sharply at 126", grow at its expense.The two substances are distinguished by their Wering behaviourwith rea'gents in the sense already indicated, so that this is a truecase of tautomerism involving two chemical individuals which arein equilibrium in solution.Both yellow and colourless forms areunimolecular in solution and this is also true of benzils which exist7 1 A. Schhberg and 0. Kraemer, Ber., 1922, 55, [B], 1174; A., i, 663;A. Schanberg and W. Bleyberg, ibid., 3753.7% T., 1907, 91, 541. The substance first saw the light, which it refusedto absorb, in the chemical laboratories of the University of Leipzig. Thecomment of Wislicenus, " Dua ist 7ceh benzi2," does no6 appear to have beenfar from the mark110 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.exclusively in yellow or colourless modifications respectively. Thus2 : 2’-diethoxybenzil is unimolecular in its colourless solutions. Thephenomenon is accordingly not at all analogous to the polymeris-ation of coloured nitroso-compounds to colourless dimerides.Oneconsequence of this work and that of Willstatter is to dispose of theidea that the colour of the a-diketones and of the quinones is dueto oscillations between diketonic and peroxidic forms. In solutionsin which equilibrium is established the colour is of feeble intensityon account of the lower concentration of the coloured modification.Another new type of tautomerism (ring-chain), which can be followedby a colour change due to the production of an a-diketonic group, isexhibited by the remarkable compound having the constitution VI.W.) /\/\CMe-CHz*C02H I I /\/\CMe-CH,*?O (vI.coYellow. colour~ea8.The substance clearly fulfils the requirements of true tautomerismand can be converted into derivatives from the diketonic form (V)or from the lactonic form (VI).With o-phenylenediamine, ityields a quinoxaline, and oxidises as a diketone when treated withhydrogen peroxide. On the other hand, acetylation produces theacetyl derivative of the keto-lactone. The colourless solution inwater becomes yellow on heating and colourless again on coolingand it is important to notice that the same change occurs in neutralsolvents, although more slowly.73 In alkaline solution there isevidence of ring-chain tautomesism of another kind, but this isbest discussed in connexion with a different example which has theadded interest that the occurrence of the phenomenon was antici-pated as the result of theoretical considerations.’*The ordinary keto-enol isomeric change may be regarded as areversible aldol-type condensation involving a carbonyl group andthe methylene group, activated by itself, often, however, assistedin the latter function by other groups such as the carbethoxylin ethyl acetoacetate. In suitably constituted substances, theoarbonyl and methylene groups might be separated by a chain ofatoms, and the object of the work now under discussion was to findsuch a case in which the separation is by one carbon atom. Inother words, to realise the equilibrium :CH2 CI-I,&b( OH)--0co \/vC079 G. A. R. Kon, A. Stevenson, and J. F. Thorpe, T., 1922,121, 650.74 S. S. Deshapande and J. F. Thorpe, ibid., 1430ORQANIO CHEMISTRY.111The series chosen for investigation was that of the a-ketoglutaricacids, and earlier work had shown that a-kefo- pp-dimethylglutaricacid exists in the open-chain form (VII), whilst the related cyclo-hexane derivative prefers the hydroxy-ring arrangement (VIII).This was explained in terms of a hypothesis relating to theeffect of attached groups on the carbon tetrahedral angle. Thetwo methyl groups in VII do not bring the methylene and carbonylgroups into sufficiently close proximity, whilst the effect of thecycZohexane ring in VIII is to cause them to approach so close toone another that the cyclopropane ring is readily formed and alsostable. In order to realise tautomerism it was desirable to findsubstituting groups in the P-positions which would have an effectgreater than that of gem-dimethyl and less than that of penta-methylene. Theoretically, this should be found in the gem-diethylgroup, and a-keto- PP-diethylglutaric acid (IX) was accordinglyprepared by the action of very concentrated, hot aqueous potassiumhydroxide on ethyl aa’-dibrorno-pp-diethylglutarate (XI).Theconditions can be so adjusted that either the acid (IX) or thehydroxy-ring acid (X) constitutes the main product, and the twosubstances can be separated by means of ether, which dissolves theformer only.CO*C02H (OHkC02* Et2C<8 HBr*CO,EtEt2c<CH2*C0,H Et2c<8H*CO&I HBr *CO,Et(E.) (X. 1 (XI. 1These compounds are not themselves tautomerides, but atautomeric equilibrium of their salts is set up in a concentratedsolution of potassium hydroxide (64 per cent.).The equilibriummixture reached from either side contains approximately 38 percent. of the keto-form. The tendency of this series of researches isto show that tautomerism of the ring-chain type may be anticipatedas the result of reversible intramolecular additions analogous toall known intermolecular reversible additive reactions capable ofjoining two chains. Stereochemical considerations, and thoseconnected with reactivity in general, are introduced in order toarrive a t suitable test cases. Just as the keto-enol change is thesimplest example of the reversible addition of -CH, to -C=O,so the glutaconic acid, three-carbon tautomerism is the simplestknown case of reversible addition of -CH2- to - G C . Nowthe best knowq reversible intermolecular reaction of the latter kindis the Michael condensation, and an exhaustive investigation 76 hasC.I(. Ingold, E. A. Perren, and J. F. Thorpe, T., 1922,121,1765112 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.brought to light several examples of ring-chain tautomerism inwhich the equilibrium set up is strictly analogous to that resultingwhen sodiomalonic ester is allowed to react with an @-unsaturatedester.76 A summary of the whole of the work on this subjectcannot even be attempted, but an isolated example may bementioned. The action of piperidine on ethyl dicarboxygluta-conate (XII) 77 leads to the formation of the esters XI11 and XIVin successive stages, and the process is reversed by sodium ethoxide.(XII.) (XIII.)(CO,Et),CH*$!H* (C0,Et ),(CO,Et),C- CH*CH(CO,Et),The individuals XI11 and XIV can be separated and isolated, theformer being a liquid and the latter a solid, melting a t 103". Thetwo substances have, however, been shown to be in tautomericequilibrium in a solvent or at slightly higher than normal t,emper-atures so as to avoid the disturbance produced by crystallisation.The mixture contains about 80 per cent. of the cyclic ester (XIV)and the attainment of equilibrium is much facilitated by the additionof piperidine, although not absolutely dependent on this. Althoughthe isomeric changes involved are far more sluggish than thosewith which we are familiar in the case of ethyl acetoacetate, theclaim is justified that the term tautomerism is equally applicable toboth examples.When ring-chain tautomerism involves the pro-duction of a bridge in a substance already cyclic, it is called intra-annular tautornerism and the distinction is not only convenient butalso desirable from the point of view that what may be called thechemical potential of the groups involved need not be so great as inring-chain tautomerism owing to the close space relationship ofsome of the constituent atoms of a ring. It has already been shownthat the acid XV behaves in some of its reactions as if it had theformula XVI.78A n even more complete investigation of the decarboxylated acid(XVII) has now been carried out with results which demonstratethe existence of the indicated equilibri~m.'~ The question of theformula to be assigned to the solid acid has not yet been answered.'6 C. K.Ingold and E. A. Perren, T., 1922, 121, 1582; C. K. Ingold andW. J. Powell, ibid., 1796.77 Guthzeit, Ber., 1901,34, 675; Guthzeit, Weiss, and Schafer, J. pr. Chem.,1909, [ii], 80, 412.7e E. H. Fanner and C. K. Ingold, T., 1920,117, 1362.7* E. H. Farmer, C. I(. Ingold, and J. F. Thorpe, ibid., 1922,121, 128ORGANIC CHEMIS!L'RY. 113The following relations illustrate a part of the proof of the separateexistence of the isomerides which is offered.x" 0 w L2-V0"l x u-u-u/114 ANNUAL REPORTS ON THE PROGRESS OB CHEMISTRY. .This again is a perfectly clear case in which the reaction involvedis analogous to the Michael condensation, being a n addition of-CH2-, u- to carbonyl, to an up-unsaturated ketone.Analogiesare not, however, so readily found for another case of intra-annulartautomerism which is now suspected to occur in the well-knownsubstance, a-campholytic acid (XVIII).80(XVIII.) C&2<CMe----CH - ---- CMe2<?Me-?H2CH(CO,H)*hH, C (C0,H) CH,The discussion of the evidence, which is based on a study of theoxidation of the acid under various conditions, involves a closelyreasoned and somewhat complex argument which does not lenditself to summarisation. The following are some of the points.Alkaline permanganate oxidises a-campholytic acid to the glycolXIX and the keto-dibasic acid XX and this is consistent with thedouble-bonded formula only.On the other hand, acidified chlorate and osmium tetroxide in thecold produces several products, among which are found the tau-tomeric substance often called Balbiano's acid (XXI) and a lactonicacid of the formula XXII.,CHMe*COcMez<b(OH)*C02H * cMe2<CO*C02H CH*CO,HCMe*CO,H CHMe*C02H CMe,, /o/(XXI.) (XXII. )The latter substance was compared with a specimen syntheticallyprepared. These and other results are regarded as proving thata-campholytic acid also exists in the bridged-ring form and thatthe substance exhibits intra-annular tautomerism. It is certainlydiEicult to imagine a different interpretation of the results, but theproof is not quite so conclusive as in some of the other new cases oftautomerism, because it depends wholly on the course of degrada-tions which might involve some obscure transformation.Ring Formation.The value of the theory connecting the angles between carbon-to-carbon valencies and the atomic volumes of the attached groupsis confirmed in a general way by the correspondence between theanticipated order of sequence in a series of substances and the factsobserved in relation to such properties as the ease of formation00 J.P. C. Chandrasena, C. K. Ingold, and J. F. Thorpe, T., 1922, 121,1542ORGANIC CHEMISTRY. 116of cyclic compounds. In the three compounds glutaric acid,p-methylglutaric acid, and PP-dimethglglutaric acid, the calculatedangles are as indicated and it has been shown that the ease offormation of the cyclopropane ring, by connecting the carbon atomsin the a-positions, increases 'as this angle diminishes./rCH2*C02H p32*C02H CH,4?2.?~c02H MeCH :112-5O Me2C 109-5"CH,*CO,H \CH,*C 0,H yCH2*C0,HThe method adopted was similar to that used previously andconsisted in estimating as far as possible all the products formedby the treatment of the esters of tho a-bromo-acids with alkaliunder standard conditions. In the following table, taken from theoriginal,81 the new data are those for the p-niethylglutaric acidseries and it should be noted that the amount of cyclopropane acidsquoted includes the products which can only have been derived bysubsequent decomposition of these substances.Derivatives from/ &methyl- BB-dirnethy;glutaric acid glutaric acid glutaric acidProducts. per cent.per cent. per cent.a-Hydroxyglutaric acids ...... 16 8 4CycZoPropane aoids ............ 47 64 84Glutaconic acids ............... 3 9 066 81 88- - -These results are in excellent agreement with the theory and itshould be remarked that non-steric effects are to a large extenteliminated by the method chosen, which is to compare the extentof ring formation with the extent of occurrence of a side reaction,in this case hydroxylation. It is a reasonable assumption thatchanges in the reactivity of the bromine would be approximatelyequally effective in stimulating and retarding both reactions. Suchresults are not related, however, to the precise angles quoted in anyway except by the placing of a series in a certain order.Com-pounds of the type RR'C<?(CN)*co>NH have been prepared inorder to compare the effects of the substituents R,R' on thestability of the cyclopropane ring.82 Previous work had shown thatwhen R and R' are methyl, the hydrolysis of the complex gives anopen-chain hydroxy-acid (lactone), whilst, under similar conditions,the three-carbon ring remains intact when CRR' is cyclohexylene.But this characteristic stability is destroyed by the substitution ofa methyl group in positions 3 or 4 in the cyclohexane ring; a veryC(CN)*COC. K. Ingold, T., 1922,121, 2676.S. F. Birch and J. F. Thorpe, ibid., 1821116 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.remarkable result which would seem to imply a steric effect a t adistance, possibly having some connexion with the varieties ofbuckling, of which the cyclohexane ring appears to be capable. Inrelation to this subject it may be noted that cis- and trans-cyclo-hexane-1 : 2-dicarboxylic acids both form inner anhydrides, ofwhich the former is the more stable and is produced from the2 runs-anhydride on heating.83It has frequently been observed that erne of formation andstability of cyclic systems are not necessarily parallel and the cyclo-butane series furnishes some of the best examples. Thus cyclo-butanone, hitherto a very inaccessible compound, may be obtainedin a yield of 15 per cent. by the pyrogenio decomposition of 1-hydroxycyclobutane- 1 -carboxylic acid and is consequently a verystable substance.84CH2<g2>C(OH)*C02H 2 + CH2<g2>C0 + CO + H20.In contrast, cyclobutanone derivatives can only be prepared bythe aid of the Dieckmann reaction in exceptionally favourablecases and then only in very poor yields.Ethyl cyclohexane-l : 1-diacetate (I) reacts with potassium in xylene solution with formationof a mixture of products from which cyclohexaneqGrocycZobutanone(11) and cyclohexanespirocyclopentane-3 : 4-&one (111) can bei ~ o h t e d . ~ ~CH2<CH2' cH2>,<cH2*z0CH2*CH2 CH2* 0(111.)The cyclobutanone derivative is a stable saturated ketone, whichis unfortunately obtained in a yield amounting to little more than1 per cent. Its formation is an indication that the Dieclunannreaction occurs, but does not prove this, as the ketone might havebeen derived from I11 by a degradation similar to that whichphenanthraquinone suffers in its change to fluorenone. Thesuggested mechanism of formation of the diketone I11 is the follow-R<CH2*CO*OEt R<CH2*$! 0R<CH2*G02EX CH,*CO 2 CH,*CHO -+ CH2*C0aa A.Windaus and W. Huckel, Nachr. Ges. Wh. Qdttingen, Math. phy8ic.84 W. J. Demjanov and (Miss) M. Dojarenko, Ber., 1922, 55, [B], 2737;85 C. A. R. Kon, T.,X1922,121, 620.ing:CH,*CO,Et + P--$!H*CQ,EtKZasee, 1920, 11, ii, 181 ; A., i, 658.A., i, 1161ORGANIC CHEMISTRY. 117It seems simpler to regard it as a, pinacol-like reductionof the carbethoxyl groups thus : -C02Et + K 4 Q(OK)*OEt ;2O(OK)*OEt -+ -CO*CO- + 2KOEt. The diketone may then bereduced to a keto-alcohol, and this view is supported by the factthat ethyl diethoxyacetate reacts with potassium with formationof the ketonic alcohol, (EtO)2CH*CO*CH(OH)*CH(OEt)2.86A systematic investigation of the application of the Dieckmannreaction to the preparation of benzoketopolymethylenes has beencommenced by a study of one of the more favourable cases.Theaction of sodium a t 100" on a toluene solution of ethyl o-phenyl-enediacetate (IV) causes the separation of the sodium derivativeof ethyl 2-hydrindone-l-carboxylate (V) in a yield of 90 per cent.of that theoretically possible.8'INatural Products.The terpene present in the essential oil from AndropogonJwarancusa, Jones, appears to be A4-carene (I). This conclusionis based on the following facts.88 The hydrocarbon is dicyclic,as it forms a dibromide and a monohydrochloride in etherealsolution.In acetic acid solution, it forms a dihydrochloride,identified as dipenteiie dihydrochloride, and in addition an oily di-hydrochloride, probably that of sylvestrene, because the regeneratedterpene gives the highly specific reaction with acetic anhydride andsulphuric acid. This indicates very clearly a hydrocarbon of thecarene group. In contradistinction from the A3-carene (11),which has been proved to occur in the oil of Pinus Zongif~lia,~~ themolecular refraction showed considerable exaltation, which is inagreement with the suggested formula.P C F C P co(1.1 (11.1 (111.)s6 A. Wohl and B. Mylo, Ber., 1912, 45, 322.8' W. H. Perkin and A. F.Titley, T., 1922, 121, 1562.J. L. Simonsen, ibid., 2292.Ibid., 1920, 117, 570118 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,The results of peimanganate oxidation are consistent with thecarene structure, since the main product is an optically activeacid isomeric with phonic acid. It probably has the constitutionI11 and is changed by hypobromite into bromoform and an isomerideof pinic acid. The ease with which the ring may be opened is anargument in favour of the cycbpropane formula. It is remarkablethat two members of the carene group, which had not previouslybeen found to occur in nature, should have been isolated by oneinvestigator during such a short period of time. A substantialaccretion to our knowledge of the sesquiterpenes has resulted froman investigation of the nature of the aromatic compounds whichare produced from them by heating with sulphur.90 Dehydro-genation in this way converts cadinene, tetrahydrocadinene,calamenol, calamene, calamenene, zingiberene, isozingiberene, andthe sesquiterpene from Javanese citronella oil into one and the samehydrocarbon, C15Hl,, termed cadalene.This is clearly a naphtha-lene derivative and on the assumption that the relation of the open-chain alcohol, farnesol, to cadinene is analogous to that of a typicalolefine terpene alcohol of the Clo-group to a p-cymenoid terpene,the guess was made that cadalene should be 1 : 6-dimethyl-4-iso-propylnaphthalene (IV). A synthesis of the latter hydrocarbonwm carried out and the substance was found to be identical withcadalene.The later stages are indicated below :Me Me CH,/\CH, CH, CHMe COCl lll01.r f\(\7H2 I I\/ \/\/CHMePrs COPrs KMe Me CH,/\/\$?HZ -+ /\/\s 1 I IMe (Iv.)\/\/I IPrS CH*OH PreVery valuable information regarding the carbon skeleton of somesesquiterpenes is thus obtained, but the reservation is made thatsince zingiberene is monocyclic it is evident that the naphthalenering is to be regarded as only potentially present in the molecule.When eudesmol and selinene are heated with sulphur, a hydro-carbon, Cl4HI4, called eudalene, is produced. This also is a naphtha-lene derivative and its production is supposed to be due to theoccurrence in the parent niolecule of a methyl group which cannotso L. Ruzicka, J.Meyer, and M. Mingazinni, Helv. C h h . Acta, 1922, 5,345; A., i, 560; L. Ruzicka and C. F. Seidel, ibid., 369; A., i, 562 ; L. Ruzickaand M. Mingazzini, ibid., 710; A., i, 1001ORGANIC CHEMISTRY. 119survive the transition into an aromatic compound. A similar caseis the production of retene from abietic acid. Cadalene (IV) onoxidation with chromic acid yields a naphthoic acid, CI5Hl6O2,which must have the constitution V because it can be converted toa methylisopropylnaphthalene (VI) which is not identical with thesynthesised 1 -methyl-4-isopropylnaphthalene (VII).CO,H PrS Me(V. ) (VI. 1 (VII. )Neither VI nor VII is identical with eudalene, which is thereforenot an apocadalene as was a t first supposed. Ruzicka and hiscollaborators have also attacked the problem of the constitutionof abietic acid, but the discussion of the results as well as of thoseof Windaus and his co-workers on cholesterol, the bile-acids, andallied subjects must be deferred.It is not too optimistic to hopethat a little more information will enable the final elucidation ofthese problems to be chronicled.The main constituent of Japanese lac is a mixture, called urushiol,containing 10 per cent. of hydrourushiol, into which all the otherconstituents are converted by reduction. Hydrourushiol has alreadybeen shown to be 2 : 3-dihydroxy-n-pentadecylbenzene (VIII).OH OH(VIII.) / I )gHH ()OH[CH&*CH:CH* [CH2],*CHs /- \/ 15 31The products of the action of ozone on urushiol diacetate and di-methyl ether are such as can be explained by the supposition thaturushiol contains the compoundsand C6H3( OH)2*[CH2],*CH:CH*[CH2]4*CH:CH2.g1 The main consti-tuent of Indo-Chinese lac called " laccol " has the constitution IX.92Its dimethyl ether yields a mono-ozonide which is decomposedby boiling water with formation of heptaldehyde, nonane-od-dicarboxylic acid, and an aldehyde of the compositionC6H3( OMe),*[CH,],*CHO. The simultaneous formation of acet-aldehyde and formic acid as well as of more complex fatty-aromaticaldehydes indicates the occurrence of constituents of laccol otherthan IX, but these are probably all closely related. Hydrolaccoldimethyl ether forms a mononitro- and a dinitro-derivative and thelatter fact suffices to prove that the substance cannot be a 4-aub-C&3( OH),* [CH,],*CH:CH*[CkI,],*CH3*l R.Majima, Ber., 1922, 55, [B], 172; A,, i, 262.Ibid., 191 ; A., i, 263120 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.stituted veratrole. The outcome of the attempt to dinitrate4-alkylveratroles is invariably to produce 4 : 5-dinitroveratrole asthe result of displacement.Burmese lac contains “ thitsiol ” reducible to hydrothitsiol, whichis shown to be 4-n-heptadecylcatechol (X) by direct synthesis.Margaric acid is condensed with catechol in presence of stannicchloride, and the 3 : 4-dihydroxyphenyl heptadecyl ketone is thenreduced by means of amalgamated zinc and hydrochloric acid(Clemmensen).Hydrothitsiol dimethyl ether forms only a mononitro-derivative(XI).Urushiol is accordingly but one member of a considerablegroup of related substances, derivatives of catechol substituted inboth 3- and 4-positions by saturated and unsaturated normalchains identical with those which occur in the higher fatty acids.The novelty and interest of this work need not be emphasised.Hyssop plants attacked by fungi contain a rhamno-glucoside,hyssopin, C50H,60m,3H,0, which yields hyssopinglycone, C16H1406,on hydroly~is.~~ The latter appears to be an analogue of butein(XII), which is produced by the action of alkali on butin, a con-stituent of Butea f rondosa.94 Hyssopinglycone, an ochre-yellow,crystalline substance, is hydrolysed by hot 33 per cent. aqueouspotassium hydroxide with formation of phloroglucinol and aceto-piperone (XIII).It should therefore have the formula XIV, especially sincebutein, when similarly treated, gives resacetophenone, but theconstitution actually advanced is XV, in which the aromatic groupsare transposed.00 0HO/\OH /\/\ H0f)OH /\/\I ICH: C H ~ O !, ), / C H 2 \,co*cH:cH!,,(,!!~~0 OH 0\/OH(XIV.) mv.193 0. A. Oestcrlo, Schweiz. Apoth. Ztg., 1921, 59, 548; A., i, 849; ibid.,It has only been possible to 1922, 60, 441; Chem. Zentr., 1922, iii, 1300.consult the abstraots. *’ A. G. Perkin asd J. J. Hummel, T., 1904, 85, 1459ORaANICl CHEMISTRY. 121Chrysophanic acid has been synthesised and thus definitelyproved to be 1 : 8-dihydroxy-3-methylanthraquinone (XVI).95OH OHThe details of the method employed follow normal lines, the startingpoints being a-nitrophtlialic anhydride and m-cresol.At the sametime the constitutions of rhein and aloemodin are finally decided,since these two substances and chrysophanic acid are known todiffer only in the side chain, which is -C02H, --CH,*OH, and-CH,, respectively.Polycyclic Group.As usual, a, great amount of systematic work in the naphthaleneand anthracene series has been published during the past year, andthe new availability of tetrahydronaphthalene has naturally beenexploited to the full. In view, however, of the existence of Reportson the Progress of Technological Chemistry, the discussion of thesesubjects may be confined to the remark, in no way deprecatory,that the literature has been enriched by the description of vastnumbers of new compounds.In view of the importance of boric acid in the chemistry ofanthracene derivatives, the isolation of definite boric compounds inthe anthraquinone group is of interest .96 1 -Hydroxysnthraquinoneis transformed by the action of a solution of boric acid inacetic anhydride into 1 - hydroxyanthraquinon yl boroace t ate,C14T-1702*O*B(OA~)2, which loses a molecule of acetic anhydride onheating in a vacuum, yielding the metaborate, C14H702*O*B0, but2-hydroxyanthraquinone does not behave in a parallel manner.This is but one instance of a characteristic difTerence in behaviourof hydroxyl groups in the a- and p-positions in the anthraquinonenucleus and it is clearly a question of some kind of association, inthe former case, of the hydroxyl with the neighbouring carbonyl.The stability of the boroacetate already mentioned can, for example, .be roughly reprcsented by formula I.This is confirmed by thefacts that 1 : 5-dihydroxyanthraquinone reacts with two moleculesof boroacetic anhydride, the 1 : 8-isomeride with one only, and1 : 4 : 5-trihydroxyanthraquinone suffers boroacetylation of twohydroxyls and acetylation of the third. The difficulty experiencedin acctylating l-hydroxyanthraquinones is also ascribed to a mutualpartial valency saturation of the hydroxyl and carbonyl groups andthis theory serves to explain why chrysazin is more readily niono-s~ R. Eder and C. Widmer, Hdv. Chim. Acta, 1922, 5, 3 ; A., i, 260.p6 0. Dimroth and T. Faus9, Ber., 1921, 54, [B], 3020; A., i, 156122 ANNUAL REPORTS ON THE PROGRESS OF CHEMTSTRY.acetylated than anthrarufin.The carbonyl group is supposed tobe unable to neutralise more than one of the hydroxyls in thea-position. Relations between the quinone oxygen and auxochromesin the a-position have also been postulated in order to account forthe tinctorial and dyeing properties of members of the anthra-quinone group and it is worthy of note that the more useful dyestuffsbelong to the 1 : 4- or 1 : 5-series, in which both carbonyls can sofunction. In addition, the plan of increasing the number of auxo-chromes in anthraquinone dyestuff -types seldom produces thedesirable results which may have been anticipated. In thechlorate-alkali fusion of benzanthrone, which converts this Substanceinto 2-hydroxybenzanthrone (11) it has been found that the yieldbecomes almost quantitative when anthraquinone i s added to themixture.97 The constitution of the substance, which may also beobtained by the action of glycerol and sulphuric acid on 2-hydroxy-anthranol, has been proved by the identification of the product ofoxidation of its methyl ether with 2-methoxyanthraquinone-l-carboxylic acid (III).98(1.1 (11.1 (111.)Reduction of anthraquinone to anthranol is readily effected byheating with dextrose and alkali solution under pressure,99 butwhen the reaction was applied to 2-hydroxyanthraquinone themain product was the acid IV.This readily forms a lactone andits methyl ether yields I11 and other substances on oxidation. Itis possible to replace the dextrose used by other carbohydrates, andeven by glycerol, which must clearly undergo condensation beforeit can supply the necessary chain of four carbon at0ms.lO 7 A.G. Perkin and G. D. Spencer, T., 1922, 121, 474.0 8 A. G. Perkin, ibid., 1920,111, 698.Idem., Brit. Pat. 161707, 1920.1 G. G. Bradshaw and A. G. Perkin, P., 1922,121, 911ORGANIC CHEMISTRY. 123A direct synthesis of pyrene from naphthalene has been carriedout and the stages are as indicated in the following scheme. Thestarting point is obtained by the condensation of naphthalene andmalonyl bromide in presence of aluminium chloride, and the sub-stance VI by an analogous method applied to V.2Miscellaneous.Benmldehyde-copper.-Nickel, iron, and aluminium have noaction on benzaldehyde, but lead and magnesium dissolve to ayellowish-brown solution, zinc to a greenish-brown, silver to abrownish-black, cobalt to a brown, and copper to a green solution.In the case of copper, the substance formed is a green additiveproduct, (Ph*CHO),Cu, which can be crystallised from toluene.It is remarkably stable, being unattacked by dilute hydrochloricacid or alkalis, but is oxidised to benzoic acid by dilute nitric acid.The constitution of the compound is not yet clear, the obvious possi-bility that it is copper hydrobenzoin being difficult to reconcile withthe stability to acids3Enolisation of Acids.-The acetal of phenyllreten can be preparedby careful distillation of the ortho-ester of phenylacetic acid withphosphoric acid in a vacuum : *Compared with keten, it is quite stable, but is attacked by waterwith formation of ethyl phenylacetate and by bromine with form-ation of ethyl phenylbromoacetate.The metallic derivatives ofa I(. Fleischer and E. Retze, Ber., 1922, 55, [B], 3280; A., i, 1138.* A. L. Bernoulli and F. Schaaf, Hdv. Chim. A&, 1922,5, 721; A., i, 1029.H. Staudinger and G. Rathsam, ibid., 645; A., i, 1014124 ANNUAL REPORTS ON THE PROQRESS OB' CHICMISTBY.carboxylic esters such as malonic ester are in all probability analog-ously constituted and contain the group :C(OEt)*OM. This hypo-thesis is supported by the behaviour of the potassio-derivatives ofdiphenylacetic acid and its ester, since tlhese are highly unsaturatedsubstance^.^ Potassamide reacts with ethyl diphenylacetate inliquid ammonia to form an additive product which, on heating ina vacuum at 100-120", loses ammonia, yielding potassoxyethoxy-diphenylketen, CPh,:C( OEt)*OK.This salt is spontaneouslyoxidised by oxygen and on treatment with methyl iodide gives ethylaa-diphenylpropionate, CPh,Me*CO,Et. It reacts with diphenyl-keten to form tetraphenylacetone and tetraphenylallene and althoughthe production of the latter is said to be difficult to explain, it appearst o fall into line with the usual schemes of addition and division :Ph,C:C( OEt)*OIC ~ Ph&-$J(OEt)*OK_, ph2g + KEtCO,.Ph,C:C:O Ph,C:C-0 Ph,C:CThe reaction affords further proof, if that were necessary, of theconstitution assigned to the potassium derivative. When potassiumdiphenylacetate is treated with potassamide in liquid ammoniasolution, it yields an amorphous, yellow precipitate of the composi-tion and formula, CPh,:C(OK),.This substance is a t once oxidisedby oxygen with production of an explosive peroxide, but carefultreatment in toluene solution wit,h air gives a monoxide probablyhaving the structure, ph2?>C( OK),, because aqueous acids oralkalis change it into benzilic acid. Alkylation of the dipotassoxy-compound with methyl iodide produces potassium aa-diphenyl-propionate, whilst the action of methyl sulphate results in theformation of the corresponding methyl ester. These experimentsprovide further evidence that the metallic derivatives of the enolisedforms of esters are directly alkylated on tlie carbon.Possibly themost satisfactory representation of sodio-compounds of the familiartype is as complex compounds, for example, [CN*CH*CO,Et]Na, inwhich formula the bonds merely represent the mode of linking ofatoms and have no implications in regard t o the distribution ofaffinity. The problem of relative ease of enolisation of acids andtheir derivatives can also be attacked by stereochemical methods,and the racemisation of optically acid amides has been studied fromthis point of view.6 Of the substances examined, d-tartamide,d-a-hydroxy- p-phenylpropionamide, CH,Ph*CH( OH)*CO-NH,, Z- p-hydroxy-p-phenylpropionamide, HO*CHPh*CH,*CO*NH,, d-mono-06 H. Staudinger and P. Meyer, Helv.Chim. Acta, 1922, 5, 656; A., i, 1015.6 A. McKenzie and (Miss) I. A. Smith, T'.? 1932, 121, 1348ORGANIC CHEMISmY. 126ethoxysuccinamide, and Z-atrolactinamide, HO*CPhMe*CO*NH,,were not raceniised in cold alcoholic solution in presence of smallquantities of potassium hydroxide. On the ot,her hand, d-dimeth-oxysuccinamide, Z-monomethoxysuccihainide, and Z-mandelo-ethylamide were slowly racernised in similar circumstances, andZ-mandelamide, Z-phenylmethoxyacetamide, and l-phenyl-p-tolyl-acetamide exhibited the phenomenon with increasing facility in theorder named.The latter observation is explained by the increased mobility ofthe hydrogen atom in the a-position which is the result of the highvalency demands of the alkyloxy and aryl groups as illustrated inthe expression :,I 11There has been much activity during the year in coniiexion witharyl derivatives of boron, phosphorus, arsenic, chromium, bismuth,lead, thallium, and other elements, but it has not been foundpossible to include a, section dealing with thc results, which arenevertheless of very considerable interest.It.ROBINSON.PART III.-HETEROCYCLIC DIVISION.THERE are no outstanding features to which particular attentionmay be directed in this Report. Rather the year has been oneof quiet progress and consolidation of previous work, involvingin several directions a revision of earlier conclusions.Ring Formation and Xtability.that the points of attacli-ment to a carbon atom of two groups, known to exert sterichindrance, are normally, in virtue of their large molecular volume,further apart than would be indicated by the regular tetrahedraldistribution. The view has since been developed that, in general,each atom attached to a carbon atom occupies a spherical domain,Some years a,go, it was suggestedJ. Kenner, T., 1914, 105, 2688.C.K. Ingold, ibid., 1921, 119, 305126 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the cubic content of which is proportional to its atomic volume.By calculation on this basis, the following values were deducedfor t,he angle, 26, subtended by two carbon atoms attached to acentral carbon atom, carrying two other groups, RR' :RR'. H,H. H,Me. Me,Me. Et,Et. (CH,),. (CH,),.26 115.3" 112.5' 109-5O 107' 116.9" 113.0"E' 11.2 2.28 0.551 0.146 13.8 2.63The last two values are for a pair of carbon atoms attached toa cyclopropane and t o a cyclobutane ring, respectively, and arcderived on the assumption that the position of these is such asto trisect the solid angle round the central carbon atom andexternal to the ring.3 This would seem to be a logical extensionof Werner's view as to the cause of the regular tetrahedral dis-tribution of four similar groups attached to a carbon atom, andthe experimental evidence in favour of the corollary appears tobe a valuable confirmation of the main proposition.In the above table, k' is proportional to the velocity constantsof hydrolysis of the hydantoins by baryta :The agreement between the order of the constants and that ofthe values of 26 is regarded as confirming the accuracy of themethod of calculating X4 It will be noted, however, that thevalues quoted for 26 are not properly applicable to this case, inwhich one carbon atom ,is replaced by a nitrogen atom, moreespecially as t'he atomic volume of the latter is very small.5 Theorder of the corrected values for 26 will, however, very possiblybe the same and thus correspond with those of k', although it isless certain that this will also hold for the cyclo-propylene and-butylene residues. It may also be suggested that other atomsthan those immediately attached to the central carbon atom mustbe included in such considerations, and it is perhaps in recognitionof this that the values quoted for the methyl and ethyl groupsdiffer.It has long been known that when the quaternary ammoniumbromides (I) and (11) are heated with ammonia, they are convertedinto the compounds (111) and (IV) :3 R.M. Beesley, C. K. Ingold, and J. F. Thorpe, T., 1915, 107, 1080.5 I. Traube, Atanalen, 1895, 290, 119; A., 1896, ii, 354.8 M. Scholtz, Ber., 1891, 24, 2402; 1898, 31, 1700; A., 1891, i, 1353;C. K. Ingold, S. Sako, and J. F. Thorpe, ibid., 1922, 121, 1177.1898, i, 567ORGANIC CHEMISTRY. 127It may be that this change is simply due to the tendency ofquaternary ammonium compounds to pass under such conditionsinto derivatives of tervalent nitrogen. In any case, the instabilityof the resulting bisimines is indicated by the fact that a t 250"they break down into dihydroisoindole (V) accompanied in thesecond case by piperidine.Dihydroisoindole is in fact most con-veniently prepared by heating (I) with ammonia solution a t 250".'Hexamethyleneimine (I) is obtained in 50 per cent. yield byheating hexamethylenediamine hydrochloride, although octa-and deca-methylenediamines 10 furnish butyl- and hexyl-pyrrol-idines, respectively. The result recalls the direct formation of2-methylhexamethyleneimine by the reduction of methyl €-amino-amyl ketone (11) : l1It will perhaps be well to consider these results, and, for example,the good yield of suberone obtainable from calcium suberate, l2in the light of recent suggestions l3 that polymethylene ringscontaining more than five carbon atoms are free from tension andhave not a plane configuration.The results of earlier work l4 on the relative stability of cyclic7 J.v. B r a n and (Miss) A. Nelken, Ber., 1922, 55, [B], 2059; A., i, 863.8 F. Schmidt, ibid., 1584; A., i, 761.9 J . v. Braun and C. Miiller, ibid., 1906, 39, 4110; A., 1907, i, 28.10 F. Krafft,, ibid., 2193; A., 1906, i, 553.11 S. Gabriel, ibid., 1909, 42, 1259; A., 1909, i, 492.l2 J. N. E. Day, G. A. R. Kon, and A. Stevenson, T., 1920,119, 639.13 W. Huckel, Ber., 1920, 53, 1277; A., 1920, i, 603; H. G. Derx, Rec.14 Compare Ann. Reports, 1920, p. 103.trav. chim., 1922, 41, 312; A., i, 651128 ANNUAL REPORTS ON !l!HE PROGRESS OF CHEMTSTRY.structures containing nitrogen have been supplemented and sum-marised.15 Neither a 2-, 3-, 4-methyl-, nor a 5 : 6-methylene-dioxy-group affects the behaviour of N-methyltetrahydroquinolinemethochloride towards sodium amalgam, although that of dihydro-indole is considerably modified by either a 2- or a 3-methyl group.16As might be anticipated, a 2- or 3-phenyl group has a markedeffect on the tetrahydroquinoline structure.17 The differencebetween the results obtained by different methods of degradingsuch structures is illustrated by the case of methylisochondodendrine.By exhaustive methylation two methines are obtained, whereasthe sodium amalgam method yields one product only.18Sttention was directed in last year's Report l9 to a compound,in which tendencies towards two distinct modes of intramolecularcondensation seemed to be evenly balanced.Another instanceof this kind is now provided by the conversion of 6-methoxyindole-2-carboxydimethylacetalylmethylamide (I) under the influence ofalcoholic hydrochloric acid into a mixture of methoxyketomethyl-dihydrocarholine (11) and methoxyketomethyldihydroindolediazine(111) :It is not easy to explain the fact that the presence of the methylgroup attached to the nitrogen atom in the side chain shoulddetermine carboline formation, as contrasted with the conversionof indole-2-carboxyacetalylamide itself into ketodihydroindole-diazine. If no nuclear mefhoxyl group be present, the course of thereaction will be entirely towards carboline formation, but it isseen from the diagram that the effect of the methoxyl group is todiminish the " positive " character of the methenyl hydrogen atomof the indole nucleus, concerned in the reaction, and to enhancethat of the imino-hydrogen atom necessary for indolediazinel5 J.v. Braun and J. Seeman, Ber., 1922, 55, [B], 3818; A., 1923, i, 146.l6 J. v. Braun, K. Hside, and L. Neumann, ibid., 1916, 49, 2613; A.,l7 J. v. Braun, J. Seeman, and A. Schultheiss, ibid., 1922, 55, [ B ] , 3803;l8 F. Faltis and F. Neumann, Monatah., 1921, 42, 311; A., i, 569.1916, i, 742.A., 1923, i, 138.19- p. 112ORGANIC CHEMISTRY. 129formation.20 If this explanation be correct, it may be expectedthat a 5- or 7-methoxyl group will favour carboline formation.Such an influence of the position of methyl groups on the formationand stability of coumaranones has been noticed in previousReports.21 In this connexion, too, the results of an amplification 22of earlier work on the velocities of hydrolysis of 2-substitutedbenzoxazoles are of interest.A different effect of substituents, which is superimposed on thatassociated with their orientation, and results in a modification ofthe general condition of the molecule, is illustrated by the fact thatneither of the three nitrophenoxyacetyl chlorides is convertibleinto a coumaran~ne,~~ although the reaction is otherwise a fairlygeneral 0ne.24The synthesis of methylisopropylcoumaranone (I) by its aid 25is another illustration of the relative independence of intramolecularcondensation on steric influences.26 This point stands out moreclearly when it is noted that the rupture of the ring usually broughtabout by intermolecular hydrolysis of coumaranones, and of theirisonitroso-derivatives, does not occur in this case, possibly owingto steric protection.It is suggested 27 that the formation of cyclic additive products,for example (11), by interaction of aldehydes, ketones, or orp-un-saturated ketones and phosphorus trichloride, or compounds derivedfrom it by replacement of one or two chlorine atoms by phenyl-,phenoxy-, or ethoxy-groups,PhvH*CK:QPh (II.PhPC1,- 0PhCH:CHCOPh --+resembles the conversion of ammonia into ammonium compoundsin that in each case the tervalent atom develops two latent valencies20 W.0. Kermack, W. H. Perkin, and R. Robinson, T., 1922,121, 1872.21 Ann. Reports, 1920, 16, 101; 1921,18, 108.22 S.Skraup and (Miss) S. Moser, Ber., 1922, S5, [B], 1080; A., i, 574;compare Ann. Report, 1920, 16, 99.2s T. H. Minton and H. Stephen, T., 1922, 121, 1591.2r Ibid. 1598.2 6 E. Mameli, Gazzetta, 1922, 52, [i], 322; A., i, 669.26 Compare Ann. Repork?, 1921, 18, 108.27 J. B. Conant, J . Amer. Chem. SOC., 1921, 43, 1705 ; A., i, 41 ; J. B.Consnt, A. D. MacDonald, and A. Mc. B. Kinney, ibid., 1928; A , , i, 186;compare Ann. Report+ 1920, 17, 98.REP.-VOL . XIX . 130 ANNUAL REPORTS ON THE PROGRESS OF c-TRY.of opposite signs.28 The course of this process in its initial stagesin, for example, the addition of phosphorus trichloride to a carbonylgroup is conceived to be as follows. The positive nucleus of thecarbon atom is assumed to be exposed, through the drawing awayof its two electrons, shared with the oxygen octet, and to attractunshared electrons of the phosphorus atom.In the resultingsystem, the oxygen and phosphorus atoms are respectivelynegatively and positively charged, and therefore an inner polarbond is set up between them.The reactions of the hydrazodicarbon-mono- and -di-thiocarbon-amides provide illustrations of the principle that every chemicalsystem tends towards that condition in which the maximum ofchemical neutralisation is attained.29 For example, when hydrazo-monomethyldicarbonthiamide (I) is boiled in acid solution, thebasic iminothiodiazole methyl ether (11) and ammonia are formed,whilst in caustic alkaline solution, the acidic iminothiourazole(111) and methyl mercaptan produced :The constitution of the compounds of type (11) is confirmed bytheir synthesis by condensation of thiosemicarbazides wit.h carbondisulphide in presence of alcoholic potassium hydroxide.Aninteresting case is that of the hydrazide (IV), from which in acidsolution iminothiodiazolone (V), and in alkaline solution the sodiumsalt of thiourazole (VI) are formed as chief product :(IV.) (VII. 1 (V. 1 (VI. 1The same intermediate product (VII) may be assumed in each~ase.3~28 Compare &o (%.) G. M. Robinson and R. Robinson, T., 1917, U1,29 A. Michael, J. pr. Chem., 1899, [ii], 60, 292; A., 1900, i, 321.90 F. Arndt and E. Mil&, Ber., 1921, 54, [B], 2089; F. Arndt, E. Mjlde,and F. Tschenscher, ibid., 1922, 55, [B], 341; A., 1921, i, 842; 1922, i, 375;compare E.From, ibid., 1921, 54, [B], 2840; Anmlen, 1922, 426, 313;A., i, 62, 377; P. C. Guha, J . Amer. Chem. Soc., 1922, 44, 1502, 1510; A.,i, 875, 876.958; Ann. RepoTts, 1017,16, 134O ~ ~ U CHEMISTRY. 131The formation of cyaphenines by distillation of aryliminoalkylethersis attributed to special reactivity of nascent nitriles, since thesesuffer polymerisation only a t high temperatures or under theinfluence of catalysts .31 The change, however, occurs, althoughwith extreme slowness, a t the ordinary temperature and thereforemight possibly consist in polymerisation, followed by eliminationof alcohol.Reference has previously been made to the difficulty frequentlyattaching to the production of systems containing rings in straightalignment on either side of a benzene ring.”‘ This is noticeable inthe poor yield of 2 : 3-naphthindigotin from 3-carboxy-2-naphthyl-glycine : 33In passing, it may be noted that 8-carboxy-1 -naphthylglycinecould not be converted into a peri-naphthindig~tin.~~ Again,when 6-aminotetrahydroquinoline was submitted to the quinaldinesynthesis, a phenanthroline resulted.35 On the other hand, 2 : 6-dihydroxy-m-act-benzbispyrrole is readily produced by reductionof 4 : 6-dinitrophenylene-1 : 3-diacetic acid with ferrous sulphateand ammonia : 36Two instances of the indirect formation of structures of the generalform just referred t o may also be noticed here, although the primaryreaction does not involve a benzene nucleus.In each case thestarting material is 2 : 3-dichloro-a-naphthaquinone. This, bysuccessive treatment with aniline and with sodium sulphide, isconverted into 2 -aniline- 3 -mercapto - 1 : 4-napht haquinone (I), from81 T. B. Johnson and L. W. Baas, J . Amer. Chern. SOC., 1922, 44, 1341;ra Ann. Reports, 1921, 18, 109.33 H. E. Fierz and R. Tobler, Helu. Chirn. Acta, 1922, 5, 557; A., i, 869,34 H. E. Fierz and R. Sallmann, ibid., 560; A., i, 870.35 J. Lindner, Monatsh., 1921, 42, 421; A., i, 687.36 W. Davies and E. H. C. Rickox, T., 1922, 121, 2640.A., i, 736.F 132 ANNUAL REPORTS ON TEE PROGRESS OF CHEMISTRY.which pp-naphthaphenthiazine-6 : 1 l-quinone (PI) is obtained byatmospheric oxidation in alcoholic solution.The parent naphthaphenthiazine (111) is prepared from this byenergetic reduction with stannous ~hloride.~' Again, the originalquinone, when treated with sodium sulphide in absence of air,yields the green monosodium salt of the internal quinhydrone (I),from which 5 : 7 : 12 : 14-tetrahydroxydibenzothianthrene (11) isobtained by acid or alkaline reduction :8 S OH OHS OH B s R............................................................1 I I I I l l I I 1 I 1 1 I I I I 10 0 1 1 S OH OH S OH 0(1.) (11.) (111.),4 noteworthy reaction is the elimination of sulphur with formationof dinaphthathiophendiquinone (111), when the diquinone derivedfrom (I) is heated above its melting point in boiling nitrobenzenesolution or with concentrated sulphuric acid.38Isomerism.Further noteworthy cases of isomerism in the indazole serieshave been recorded. Freshly prepared 5-chloroindazole melts at119-120", but changes, slowly a t the ordinary temperature, andfairly rapidly at lOO", into a modification, m.p. 143-144".Similarly, the 5-bromo-derivative exists in a labile form, m. p.124-125", and a stable form, m. p. 132-133". Since each formmay be recovered unchanged after recrystallisation, they wouldseem not to be polymorphous. The failure to convert the high-melting into the low-melting isomerides suggests that their relation-ship is not one of structural isomerism, whilst the higher meltingpoint of the stable isomerides is in agreement with the hypathesisof stereoisomerism, represented by (IV) and (V),37 K.Fries and F. Kerkow, Annalen, 1922, 427, 281; A., i, 577.s8 K. Brass and L. Kohler, Ber., 1922, 65, [B], 2643; A., i, 1050ORGANIC CHEMTSTRY. 133and already applied to the 2-acylindaz~le~3.39 In agreement withthis analogy, 3-halogen indazoles do not exhibit isomerism.A fuller investigation 40 of the two forms of 3-phenylindazole,m. p. 107-108" and 115-116°41 has shown these to be inter-convertible, and, further, it would seem that the low-meltingisomeride is the more stable, since it may be obtained from theother form by distillation. The relationship is therefore consideredto be one of structural isomerism :CPh CPhThe same explanation is adopted in the case of two forms of 3 : 5-diphenylisooxazole-4-carboxylic acid (I) and (11), and of the corresponding 5-phenyl-3-methyl-derivative.In each case, the acid of lower melting point is converted by boilingcaustic alkali into its isomeride, although the reverse change hasnot been accomplished.It is hoped that further information maybe gained from attempts to resolve the acids into optically activecomponents, since the compound represented by (11) should becapable of res0lution.~2 It will be noted that the structuralformulae assigned to these pairs of compounds correspond closelywith those of the tautomeric forms of dimethyldicyclopentanone-carboxylic acid.43 It is interesting to note how in three distinctfields of investigation, the suggestion is almost simultaneouslyforthcoming that the types of bridged and unsaturated ring systemshere considered are closely related.At the same time, it mustbe observed that although the indazoles are benzopyrazoles, thetendency on the part of pyrazoles to assume the bridged structure,if existent, is very limited.448 ) K. v. Auwers and H. Lange, Ber., 1922, 55, [B], 1139; A., i, 684.40 K. v. Auwers and A. Sondheimer, ;bid., 1896,29, 1265; A., 1896, i, 503.4 1 K. v. Auwers and I(. Huttener, ibid., 1922, 56, [B], 1112; A,, i, 682.M. Betti and others, Gazzetta, 1915, 45, i, 362; ii, 151, 377; 1921, 51,ii, 229; A., 1916, i, 997; 1916, i, 222; 1922, i, 52.48 E. H. Farmer, C. K. Ingold, and J. F. Thorpe, T., 1922, 121, 128.44 K. v. Auwers and 11. Broche, Ber., 1922.56, [B], 3880; A., 1923, i, 161134 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The rearrangement of 2-hydroxy-3-phenylindazole (A), whenboiled with caustic alkali, has now been shown to consist in theinterchange of the hydroxyl and the phenyl groups,45 since theproduct furnishes azobenzene-o-carboxylic acid on oxidation andis identical with 3-hydroxy-2-phenylindazole (I), prepared fromhydra'zobenzene-o-carboxylic acid : 46(1.1It is considered that the isomerisation depends rather on a directinterchange of the groups concerned than on the formation of anytransient additive product.Isomeric forms of five-membered cyclic compounds have alsobeen observed in the pyrazolone series.Two isomerides resultfrom the methylation of 3-phenyl-5-pyrazolone (11). Of these,one, m. p. 96", is probably a methoxy-derivative, but the other,m.p. 165", is converted by phosphorus pentachloride into 5-chloro-3-phenyl-l-methylpyrazole 47 (IV), identical with the productpreviously obtained from 3-phenyl-l-methyl-5-pyrazolone, m. p.207" 48 (V) :NH NMe NMe NMe/\ '\co N-F-OH I/\ /\ M RC1 +- M PhC--6H2 PhC=zCH M FOPhC-CH, PhC-CH(W. ) (V. 1 (VI. 1A similar statement in regard to the 1-phenyl-5-methyl derivativeis already on record.49 The suggestion is made that these pairsof compounds may be stereoisomerides represented by (VI) andof the type already mentioned in the case of the indazoles. Itwill, however, be noticed that no interconversion has been accom-plished in the present insbance and that in the case of indazoles theexperimental evidence is to the effect that substitution in theposition corresponding with that occupied by the hydroxyl groupin (VI) inhibit,s stereoisomerism.4 5 K.v. Auwers and A. Sondheimer, Eoc. cit.4 6 P. Freundler, Compt. rend., 1906, 143, 909; Bull. SOC. chim., 1911, [iv],*' C. A. Rojahn, Ber., 1922, 55, [BJ, 2959, 3990; A., i, 1153.48 R. v. Rothenburg, J . pr. Ch.em., 1895, [iiJ, 52, 23; A., 1895, i, 686;qe F. Stolz, J . p ~ . Chem., 1897, [ii], 55, 164; -A,, 1897, i, 374.9, 738; A., 1907, i, 158; 1911, i, 753.A. Michaelis, Annalen, 1907, 352, 152; A., 1907, i, 246ORGANIC CHEMISTRY. 135It would appear, in fact, that, apart from the careful attemptsa t discrimination noted in the cases of the indazoles, the suggestionsmade in some of the other cases just mentioned are ad hoc incharacter, and to be received with corresponding reserve.Further, instances have not been lacking during the year whichshow the need for caution, before cases of alleged isomerism arefinally accepted.Thus, the “ isoisatogens,” obtained from isatogensby the action of alcoholic hydrogen chloride,50 are now stated tobe in reality additive compounds of isatogens with alcohol, andto be formed, although more slowly, by treatment with alcoholalone. In the case of ethyl isatogenate, the reaction is expressedas follows :OH (1.1The additive compounds are hydrolysed by cold caustic alkali toK-oxalylanthranilic acid (I) .51Again, the suggestion that the isatoids represent isomeric formsof isatin 52 has turned out to be wrong.53 These compounds, morecorrectly termed isatoid monoalkyl ethers, were originally prepared 64by interaction of alkyl iodides and the silver salt of isatin, andalso from the alkylisatins, which are the first product of the reaction,by spontaneous evaporation of their benzene solutions whileexposed to light.By hydrolysis, they are converted into anhydro-indoxyl-a-anthranilide (11), the constitution of which is indicatedby its oxidation to the known anhydro-or-isatinanthranilide (111) :CO I CO NH CO NOH(11.1 (111. )The last compound is also obtained directly from the originalethers when their alkaline solutions are exposed to light. Theexistence of isomerides of isatin 55 is still in dispute, and it is main-tained that certain of these are in reality isatoid derivatives.51 G.Heller and W. Bolsaneck, Ber., 1922, 55, [B], 474; A., i, 369.52 A. Hantzsch, Gid., 1921, 54, [B], 1221; A., 1921, i, 597.Ann. Rep*, 1919, 15, 109; 1921, 17, 116.G. Heller and W. Benade, ibid., 1922, 55, [B], 1006; A., i, 582; A.64 A. v. Baeyer and Oeconomides, ibid., 1882, 15, 2093; A., 1883, 201.65 A. Hantzsch, a i d . ; G. Heller, %%id., 2681 ; A., i, 1058; compare Ann.Hantzsch, ibid., 3180; A , , i, 1177.Reporta, 1921, 17, 116136 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.St ereoisomerism.Although there has been no novel development in the stereo-chemistry of heterocyclic compounds during the period underreview, a number of interesting applications have been made ofknown principles.Besides those already referred to, they arementioned in connexion with catechin (p. 146), picrorocellin (p. El),bishydrocarbostyril-3 : 3’-spiran (p. 152), quinine (p. 157), anhydro-ecgonine (p. 160), and scopolamine (p. 161).Alkylation.The sodium salt of 5-chloro-3-methylpyrazole gives rise to3-chloro-1 : 5-dialkyl derivative^.^^ This result is the more inter-esting since 1 : 5-dialkylpyrazoles themselves seem incapable ofexistence. Thus, alkylation of 3-alkylpyrazoles furnishes a 1 : 3-,but no 1 : &derivative. All attempts to synthesise the latter havefailed, and even when 1 : 5-dimethylpyrazoline is oxidised, 1 : 3-dimethylpyrazole is formed. Similarly, although l-phenyl-3-methylpyrazole methiodide is converted into l-phenyl-3-methyl-pyrazole by heat, the corresponding 1 - benzyl-compound yields1 : 3-dimethylpyrazole under these conditions : 57fiH EHMe SH-pMeCH--N<Me -+ CH dNMe\/ \/ INB2The properties of the methylation product from the sodium saltof 5-chloro-3-phenylpyrazole differ from those attributed to eitherof the products which might have been expected.58 The alkyl-ation of 3-phenyl-5-pyrazolone has already been referred to.Alkylation of 3-phenylindazole leads to results varying withthe conditions employed, but there is a predominant tendency forthe substituent to enter the l - p o ~ i t i o n .~ ~A new dimethyl derivative has been prepared by treating leuco-indigotin in persistently alkaline solution with methyl sulphate.This is considered to be an O-substituted compound, since it isconverted by nitrous acid into indigotin, and by chromic acid intoisatin.BOThere are grounds for the belief that alkylation of the glyoxalinesdoes not proceed by direct replacement of an imino-hydrogen66 C. A.Rojahn, Ber., 1922, 55, [BJ, 2959; A., i, 1183.5 7 I(. v. Auwers and H. Broche, ibid., 3880; A., 1923, i, 161.68 C. A. Rojahn, Eoc. cit.69 K. v. Auwers and K. Huttener, Ber., 1922, 55, [B], 112; A , , i, 682.E. Grandmougin, Compt. Tend., 1922, 174, 758; A , , i, 470ORGANIC CHEMISTRY. 137atom, and the following scheme is put forward for the cam of4-nitro-5 -methylglyoxaline :A 1 : 3-dimethyl derivative is obtained by the action of diaeo-methane on uracil. 62Fiue-membered Heterocyclic Structures.The formula of the elsholtzic acid derived from the action ofamyl nitrite and sodium ethoxide on elsholtzione 63 has now beenconfirmed by its oxidation to furan-2 : 3-dicarboxylic acid.Theconstitution of this in turn is decided by its preparation from thechloride of synthetic 64 2-methylfuran-3-carboxylic acid. Bromin-ation of this compound occurs partly in the side chain and partlyin the nucleus, so that hydrolysis of the product furnishes a bromo-2-hydroxymethylfuran-3-carboxylic acid. This undergoes oxid-ation to the corresponding dicarboxylic acid, from which the bromineis removed by means of zinc dust and ammonium chloride.65The possibility of synthesising coumarins by condensation ofphenol or their ethers with fumaric, maleic, or malic acid has beeninvestigated, but with somewhat discordant results.66A closer examination of the product of the action of acetyleneon finely divided iron pyrites a t 300" has shown that whilst thiophenconstitutes 40 per cent.of the whole, it is accompanied by its2- and 3-methyl and -ethyl derivatives, as well as by a number ofdher products, which do not contain ~ulphur.6~The resemblance between thiophen and benzene extends totheir behaviour towards ethyl diazoacetate. In the former case,reaction only occurs a t 130" in presence of an excess of thiophen.The product, obtained in poor yield, is probably ethyl dicych-Aa-a-penthiophen-5-carboxylate, RH-XH>CH*CO2Et,68 since itO2 T. B. Johnson, A. J. Hill, and F. H. Case, Proc.Nat. A d . rSci., 1922,CH*S* HF. L. Pyman, T., 1922, 121, 2619.8, 44; A., i, 471.Compare Ann. Reporb, 1920,16, 114.64 E. Benary, Ber., 1911, 44, 493; A., 1911, i, 319.O6 Y. Asahina and 5. Kuwada, J . Pharm. SOC. Japan, 1922, 485, 666; A.,O 6 G. C. Bailey and F. Boettner, J . Id. Eng. Chem., 1921, 18, 906; A.,O 7 W. Steinkopf and J. Herold, Annalen, 1922, 428, 123; A., i, 850; com-i, 1047.1921, i, 879; W. Ponndorf, D.R.-P. 338737; A , , i, 665.pare W. Steinkopf, Annalen, 1914, 403, 11 ; A , , 1914, i, 425.W. S. Steinkopf and H. Augestad-Jenaen, ibid., 164; A., i, 861.F 138 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.easily forms an amide, and therefore probably contains a secondaryrather than a tertiary carbon atom in the a-position to the carb-ethoxy -group.69The catalytic reduction of pyrrole in presence of nickel a t 200"results in the opening of the ring in every possible manner, sinceammonia, diethylamine, methyl-n-propylamine, and n-butylamineare formed, The production of n-amylamine and ethyl-n-propyl-amine a t the same time is attributed to the preliminary formationof piperidine through the intermediary of N-methylpyrr~le.~~It has been shown 71 that the pyrrole nucleus is amenable to theGattermann synthesis of aldehydes by means of hydrogen cyanide,and that, as the formula (I) and (11) show, substitution may occurin the a- as well as in the p-position.Mefi-#CO,Et HCO*R-R*CO,E t(1.1 HC0.C CMe MeC CMe (11.1\/NH\/NHIn view of this result, and the known similarity in reactivity betweenpyrrole and phenol, it is not surprising that the Hoesch synthesisalso may be applied to pyrrole.The use of cyanogen or malono-nitrile in this connexion results in the formation of cyanoketones,and not of dike tone^.'^Not only acetyl or ~arboxyl,'~ but also methyl groups 74 arereplaceable in the pyrrole nucleus by the nitro-group through theagency of nitric acid. The following formulae, in which the groupswhich suffer replacement are indicated by heavy type, suggestbhat the order of replaceability is acetyl, methyl, and carbethoxyl :MeZ-13;*CO2Et Mefi-R*COMe(HCO or) COMe-C CMe Et0,C.C CMe\/NH\/NHM e R- R O C 0 ,E tEt0,C.C CMe\/NHThe formula (111) is suggested for tripyrrole, from a determination69 Compare E.Fischer and W. Dilthey, Ber., 1902, 35, 844; A,, 1902,i, 269.70 N. J. Putochin, ibid., 1922, 55, [B], 2742; A., i, 1176.7 1 H. Fisdmr and W. Zemeck, ibid., 1942; A., i, 758.72 H. Fischer, I(. Schnelle, and W. Zerweek, ibid., 2390; A., i, 1056.7s G. Ciamician and H. Silber, ibid., 1885, 18, 1456; 1886, 19, 1078; A.,?* H. Fischer and W. Zerweck, ibid., 1922, 55, [B], 1949; A., i, 768.1885, 992; 1886, i, 718ORGANIC CFIEMIS!ERY. 139of the #-positions available for coupling with diazomium compoundsand the formation of succinic acid by oxidation with chromic acid.For similar reasons, hydroxydipyrrole is considered to be (IV) orthe corresponding ketone.758H-BH FH,--CH, 8H-fjH EH-RH SH-EH(''I.) CH C-CH bH-C CH CH C-C C*OH (IV.)\/ \/ NH NH\/NH\/ \/NH NHBy distillation of chitin with zinc dust, a mixture of bases isobtained, which contains some pyridine derivatives, but consistschiefly of pyrroles.Of the latter, one appears to be identicalwith synthetic a-methyl-N-n-hexylpyrrole, and in consequence it issuggested that the grouping (I) is present in ~hitin.7~-CH- CH(OH)*CH,*OH i C H ( ~ H ) ~ ~ H - - - ~ H ~ ~ H . ~ H . C H ( O H ) ~ ~ H ~ ~ H ( O H ) ~ IO-- 0-(I. I--In a review '7 of the various explanations which have beenoffered of the Fischer indole synthesis, preference is given to thatwhich 78 postulates the intermediate formation of an anil :NRPh*N:CR*CH,R + H, + XH,Ph + NH:CR*CH,R? J.C&&<pg>CR + H, c- NPh:CR*CH,R + NH,In order to explain the extension of the reaction to phenylmethyl-hydrazones, i t is assumed that the ketimine formed in the firststage of the reaction may react in the aminic form, NH,*CR:CHR.Reference may be made here to the synthesis of the indenoindoles(11) and (111) by heating the phenylmethylhydrazones of a- andF-hydrindones, respectively, with concentrated hydrochloric a ~ i d .7 ~CH, / L / \ 7 \ /\ /\I 1 I 1 I\/\/\/\/(I1.) I 1 I I I\/\/-\/NMe CH, NMe.The pyrogenetic synthesis of indole by passing a mixture of76 A. Pieroni and A. Moggi, Atti R. Accad. Lincei, 1922, [v], 31, i, 381;76 P. Karrer and A. I?. Smirnoff, Helu. Chim. Acta, 1922, 5, 832; A., 1923,7 7 C. Rollins. J . Amer. Chem. SOC., 1922, 44, 1508; A . , i, 863.'* G. Reddelien, Annalen, 1912, 388, 179; A., 1912, i, 363.79 J. W. Armit and R. Robinson, T., 1922, 121, 827.A., i, 766.i, 122.p *140 ANNUAL REPORTS ON TEE PROGRESS OF CHEMISTRY.aniline vapour, acetylene, and carbon dioxide through an iron tubea t 700" is moderately successful. A quantity of crude indoie wascollected amounting, in the most favourable case,*O to 34 per cent.by weight of the aniline not recovered.A new synthesis of r-tryptophan has been described. Indole issuccessively converted into magnesium p-indolyl bromide, andP-aldehydoindole, which is then condensed with hydantoin by thePerkin reaction to P-indolalhydantoin. Reduction with sodiumamalgam, followed by hydrolysis, completes the synthesis :' ) i * C H O /\fl*CH:Y-$!O(/\/CH * I/\/CH NH NH -+NH NH \/ coThe catalytic reduction of N-methyl- or -ethyl-carbazole inpresence of nickel salts at 215' under pressure and in absence ofa solvent furnishes, besides unchanged material, a mixture of thefetrahydro-derivative, insoluble in acid, and the basic octahydro-derivative (I), from which a decahydro-derivative (11) is obtainedby the action of tin and hydrochloric acid.The constitution ofthe deoxy-base (111), derived from this, follows from its hydrolysisby acids to 2-A1-cycZohexenylcycZohexanone (IV) : 82/\\/\/\/(I.) 9% g-8 p 2 -CH, C C CH,CH,NR CH,-+CH, CH,CH, YH-E YHz6H,CH C CH,/\ /\\/\/\/CHZNR CH,CHZ CH,/\ /\\/ \/y ! y?(111.) 7% f p - 8 p z + p 2 8 H - p 'iH2 (IV.)CH,CH C CH, CH, CH CO CH,CHZ CH,\/ /\/CH,RN CH,\MeThe result is of interest as indicating that the formation of pyrrolines(corresponding with 11) from pyrroles proceeds simply by theR. Majima, T.Unno, and K. Ono, Ber., 1922,55, [B], 3854; A., 1923, i, 135.dl R. Majima and M. Kotake, &id., 3869; A., 1923, i, 166.8z J. V. Braun and H. Ritter, &id., 3792; A., 1923, i, 141ORGANIC CHEMISTRY. 141reduction of one double bond rather than by reduction of theconjugated system, followed by isomerisation.The f m a t i o n of indigotin by alkaline fusion of dianilidofumaricacid, from aniline and dibromofumaric acid, has been described.ss6 : 6'-Dibromoindigotin has been isolated from the fluid expressedfrom certain varieties of cockle, which the natives of Mexico havelong utilised for dyeing purposes.84Formulae reminiscent of the indigoid type have been assigned tothe product (I) of the oxidation of rhodanine by ferric chloride,85and, provisionally, to " naphthothiam blue," (11) the leuco-com-pound of which is formed when 1 : 8-nitronaphthalenesulphinicacid is reduced with zinc dust and potassium sulphite.86In accordance with the relationship, previously noticed, betweenthe constitution of benzoxazole derivatives and the@ capacity forvisible flu0rescence,~7 (111) exhibits this property, but (IV) and(V) do not.88N N OH NImino-oxazolidines (VI) result from the condensation of styrenedibromides with carbamide :Their hydrolysis with alkali hydroxides provides a new method forthe preparation of alkamine~.~~G.C. Bailey and R. S. Potter, J . Amer. Chem. Soc., 1922, 44, 215; A , ,i, 370.84 P. Friedlmnder, Ber., 1922, 55, [B], 1655; A., i, 793.85 C. Griinecher, H. Reis, and E. Pool, Helu. Chim. Actu, 1922, 5, 382;86 A. Reissort, Ber., 1922, 55, [BJ, 868; A., i, 583.87 Compare Ann. Repor&, 1921, 18, 127.8 8 F. Henrich, H. Suntheimer, and C. Steinmann, Ber., 1922, 56, [BJ,89 J. Takeda and S. Kuroda, J . Pham. SOC. Japan, 1919, 449, 561; 1921,A., i, 576.3911 ; A , , 1923, i, 146.1; A., 1920, i, 228; 1922, i, 272142 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The evidence of the non-existence of 1 : 5-dialkylpyrazoles hasalready been summarised (p. 136). This forms a basis for anadverse criticism of Knorr's view that one hydrogen atom in thepyrazole nucleus is oscillatory and it is suggested that the causeof the apparent identity of 3- and 5-derivatives of pyrazole, onwhich this view is based, is again the instability of one form, andits consequent transition to the other.g0A study of the electrochemical oxidation of pyrazoles has shownthat, in acid suspension, the heterocyclic nucleus of l-phenyl-3-methylpyrazole is destroyed, but that in presence of potassiumcarbonate solution, the benzene nucleus is destroyed, with form-ation of pyrazole-3-carboxylic acid.91The applicability of the Friedel-Crafts reaction to 5-chloro-pyrazoles, giving rise to substitution in the 4-position, is limitedto l-aryl derivatives and to the chlorides of aromatic acids92The difficulty associated with the original explanation of thebehaviour of the 5-nitroglyoxalines on reduction was indicatedin a previous Report.g3 dl-Alanine-N-methylamidine (I) has sincebeen found among the reduction products of 5-nitro-1 : 4-dimethyl-glyoxaline (prepared by nitration of 1 : 4-dimethylglyoxaline) .Accordingly, the reaction is now considered to be analogous to therupture of the glyoxaline ring by means of benzoyl chloride andsodium hydroxide, and in the case referred to is represented asfollows :4-Nitro-1 : 5-dimethylglyoxaline, from the nitration of 1 : 5-di-me th ylglyoxaline, yielded the amino -compound, with dl -N-meth yl-alanine and ammonia.94 These results confirm the orientationsprovisionally adopted 95 for the above two dimethyl derivatives,when they were prepared from 4-methylglyoxaline, and also thesuggestion that pilocarpine is a 1 : 5-derivative of glyoxaline.Considerations of space prevent more than a reference to the dis-cussion of the behaviour of the glyoxalines on alkylation (com-pare p.136) and towards benzoyl chloride and sodium hydroxidefrom the point of view of polarity. The inadequacy of earliersuggestions in regard to the latter reaction is indicated in a review00 K. v. Auwers and H. Broche, Ber., 1922, 55, [B], 3880; A., 1923, i, 151.01 Fr. Fichter and H. de Montmollin, Helv. Chirn. Acta, 1922, 6,256; A.,92 C. A. Rojahn, Bey., 1922, 55, [B], 291; A., i, 373.93 Ann. Reports, 1920, 17, 115.94 F. L. Pyman, T., 1922, 121, 2616.95 Idem, ibid., 1910, 97, 1814.i, 470ORUANIC CHEMISTRY.143of this,96 in which it is shown that the ring may also be openedby means of isovaleryl chloride. Neither benzenesulphonyl chloridenor acetic anhydride, however, is effective. The result in thelast case is the more striking, since the same reagent opens thebenzoglyoxaline ring,g7 and yet the latter is the more resistanttowards benzoyl chloride and pyridine. These reactions permitthe conversion of glyoxalines into 2-alkyl derivatives, since it hasbeen shown 98 that when, for example, bisbenzoylaminopropylene(I), derived from 5-methylglyoxaline, is heated with the anhydrideof an aliphatic acid, 2-alkyl-5-methylglyoxaline is produced :The polybromo-compounds resulting from the direct halogenationof glyoxalines may be converted into monobromo-derivatives bytreatment with sodium sulphite solution.99The rearrangement of the system (I) in certain compounds tofurnish 1 : 2 : 3 : 4-tetrazoles would appear to be an intramolecularreaction comparable with the familiar intermolecular saturationof a double bond by the action of diazo-compounds :-c- N-(1.) -$?IN- ~ I$ CPh*Cl:N*N:CHPh (11.)Ns \/ NPh:C:NPh (III*)NSuitable azides of the type (I) are generated as intermediate pro-ducts (not isolated) by interaction of sodium azide and benzylidene-benzhydrazide chloride (11) or carbodiphenyldi-imide (111), or,in place of the latter, a mixture of a thiourea or a thiosemicarbazidewith lead 0xide.l Again, when mustard oils are heated withazoimide in an indifferent solvent, cyanamides are formed as inter-mediate products :HS*E-rPhR*N*CS + HNS + R*NHCS*NS -+ R*NH*CiN N N (v-)A.Windaus, W. DSrries, and H. Jenssen, Ber., 1921, 54, [A], 2746;A., i, 60.@' G. Heller, aid., 1904, 37, 3116; A., 1904, i, 942.98 A. Windaus and W. Langenbeck, ibid., 1922, 66, [B], 3706; A., 1923, i,@@ I. E. Balaban and F. L. Pymrtn, T., 1922,121, 947; L. Light and F. L.1297;147.Pyman, ibid., 2626.A., i, 689, 690.1 R. Stdl6, Ber., 1922, 55, [B], 1289; R. Stoll6 and A. Netz, ibt1M ANNUAL REPORTS ON THE PROQRESS OF CHEMISTRY.These then react with more azimide to form tetrazoles. 5-Mer-capto-l-phenyl-1 : 2 : 3 : 4-tetrazole (V) is formed when phenyl-carbimide is boiled with an alcoholic suspension of sodium azide,or when the corresponding thiocarbamic azide (type IV) is treatedwith alkali.2+-Aniline (VI) is the sole product of the interaction of sulphurylazide, SO,(N,),, and benzene at 14OoY3 but from p-xylene, a mixtureof +-p-xylidine with a base, possibly (VII), and a solid of the samecomposition, are formed.* The products obtained when benzylazide is heated with p-xylene, on the other hand, are entirelyderived from the azide, and include (VIII) and (IX) : 6NThe interaction of thiobenzilic acid and benzaldehyde in presenceof hydrogen chloride leads to the formation of triphenyl-1 : 3-oxthiophan-&one (I).This, on treatment with cold concentratedsulphuric acid, yields a product, to which the formula (11) is assignedon the grounds of its conversion into 9-phenylanthracene by dis-tillation with zinc dust, and of its insolubility in alkali.61 Ph,C-S-$!HPh phf-s>CHPh 0-0 + [ bO,H OHThe Pyrone Group.The method whereby pyrylium salts are synthesised by con-densation of an o-hydroxybenzaldehyde with a compound con-taining the -CH,*CO* group ' has been shown s to be applicablea E.Oliveri-Mandab, Gazzetta, 1921, 51, ii, 196; 1922, 52, i, 101; A,,a F. Sohmidt, Ber., 1922, 65, [B], 1581; A., i, 777.4 T. Curtius and F. Schmidt, ibid., 1571; A,, i, 776.5 T. Curtius and G. Ehrhardt, ibid., 1559; A., i, 775.A. Bistrzycki and B. Brenken, Helv. Chim. Acta, 1922, 6, 20; A,, i, 268.7 W. H. Perkin and R. Robinson, P., 1907, 19, 149; H. Decker and T. v.1921, i, 900; 1922, i, 473.Fhberg, Ber., 1907, 40, 3815; Annalen, 1907, 356, 281; A., 1907, i, 950.D.D. Pratt and R. Robinson, T., 1922, 121, 1577ORQANIC CHEMISTRY. 145to w-ethoxy- and -phenoxy-acetophenones, yielding compounds(I) of the anthocyanidin type.The blue anthocyanidin pigments have been considered to bealkali salts of.pheno1 betakes, for example (11). This view has,however, been criticised 9 on the ground that it cannot be appliedto the colour change of solutions of 4’-hydroxy-2-styrylbenzo-pyrylium chloride from red to blue on dilution with water, inabsence of any base. The change is attributed to production ofthe quinonoid compound (or, less probably, a correspondingbetaine) (111). The pyrylium compound in question is synthesisedby the action of hydrogen chloride on a solution of o-hydroxy-styryl methyl ketone and p-hydroxybenzaldehyde in formic acid.A synthesis of isohematein tetramethyl ether ferrichloride (IV)has been carried out lo by reactions precisely analogous to thoseused in the case of isobrazilein trimethyl ether.llOMeO -I\-/OMe OMeDemethylation of the above ferrichloride by means of hydrochloricacid furnished a product identical with the isohematein fromhaematoxylin.l2No definite conclusion has yet been reached in t,he controversy 13’ J . S. Buck and I. M. Heilbron, T., 1922, 121, 1198.lo H. G. Crabtree and R. Robinson, ibid., 1033.l1 Compare Ann. Report8, 1918, 15, 104.le J. J. Humme1 and A. G. Perkin, T., 1882, 41, 373.18 Ann. Reports, 1920, 17, 110; 1921, 18, 129; A.C. von Euler, Svensk.Kern. Tidekr., 1921, 33, 88; A., i, 45116 ANNUAL REPORTS ON THE PROQRESS OF CHEMISTRY.regarding the constitution of catechin. The crystallographicevidence in favour of a formula of the ay-diphenylpropane typehas been met with equally definite evidence of the same characterin favour of the act-type of f0rmu1a.l~ An intimation l5 that thediscrepancies are to be subjected to independent investigation istherefore to be welcomed. In this paper, the optical activity ofacacatechin is denied. On the other hand, the optical activityof the pentacetyl derivatives of three samples of catechin has beenindependently afkned,16 and evidence of a somewhat ingenioustype is also offered of the presence of two asymmetric carbonatoms in the catechin molecule. In the course of the latterinvestigation, dl-epicatechin was prepared, and then detected inPegu- ca techu .The Pyrimidines.Two new syntheses of pyrimidine derivatives have been recorded.Mono- and di-alkylmalonic esters condense with aromatic amidinesin presence of sodium ethoxide, yielding respectively insolubleyellow (I), and soluble colourless derivatives (11) : 18The condensation products of aldehydes with asparagine furnishgood yields of hydroxybromopyrimidinecarboxylic acids on oxid-ation with alkaline solutions of sodium hypobromite :H,N--QO TH*$!ORCHFH, ---+ R8 EBr#-CH*CO,Na N- C*CO,NaThe unbrominated compounds may be obtained by use of potassiumpermanganate, but the yields are not so good.The presence ofasparagine in young etiolated shoots has prompted the suggestionthat a reaction similar to these may produce the pyrimidines andpurine bases found in n~c1eoproteins.l~The desulphurisation of 9-alkyl-8-thiouric acids by treatment withnitrous acid leads to the formation of xanthines (111) :(111.) (Tv. 1M. Nierenstein, T., 1922, 121, 604.M. Nierenstein, Ber., 1922, 55, [B], 3831.1' K. Feist and A. Futtemenger, ibid., 942; A., i, 666.l7 K. Freudenberg, 0. BZlhme, and L. Purrmann, &d., 1734; A,, i, 756;1* A. W. Dox and L. Yoder, J . Amer. Ohm. SOC., 1922, 44, 311; A.,18 E. Cherbuliez and K. N. Stavritch, Helv. Chim. Acta, 1922, 5, 267;I(. Freudenberg, ibid., 1938; A., i, 756.i, 374.A., i, 581ORGANIC CHEMISTRY.147When the reaction is extended to 7 : 9-dialkyl-8-thiouric acids,sulphur is again removed, but the alkyl groups and the pyrimidinering remain intact. In accordance with the formula (IV) assignedto the resulting deoxyuric acids, acid hydrolysis gives rise todialkyluracils (V), the monoformyl derivatives of whioh are obtainedby alkaline hydrolysis.20Betaines .The discordance between the ordinary formulae for the varioustypes of betaines, including certain dyestuffs like gallocyanine,rosindone, and cyanidine, and the usual stereochemical conceptionsis well known. It has now been suggested21 that the betainestructure is not cyclic in the ordinary sense, but represents a dipolarunit, for example (I),containing within itself the opposite charges carried by the sodiumand chlorine ions in solid sodium chloride.The analogy suppliesan explanation of the high melting point and the low solubilityin organic solvents which characterise the amino-acids andbetaines.22 In further confirmation of this view, it has been shownthat a betaine results from the hydrolysis of the quaternarymethiodide of methyl trans- p-dimethylaminocinnamate (11) .23Similarly, the salts of dibasic acids with multivalent metals areto be compared with calcium carbonate.Carnitine is now considered to be a p-betaine (111), since it showsthe behaviour of a p-hydroxy-acid, in that it suffers dehydrationto apocarnitine by concentrated sulphuric acid a t 130°.24 Thisreaction distinguishes carnitine from the synthetic product,a5with which it had previously been thought identical.The formulaalso explains the formation of p-bromobetaine (IV) from carnitineon oxidation.26Apophyllenic acid is probably a 4- (I) rather than a 3-betaine,2o H. Biltz and others, Anmlen, 1922, 426, 237-299; A,, i, 380-384.21 P. Pfeiffer, Ber., 1922, 55, [B], 1762; A., i, 720.z2 Compare A. Reis, 2. Physik, 1920, 1, 204; A., 1920, ii, 637.23 P. Pfeiffer and G. Haefelin, Ber., 1922, 55, [B], 1769; A., i, 738.24 R. Engeland, ibid., 1921, 54, [B], 2208; A., 1921, i, 880.z 6 E. Fischer and A. GGddertz, ibid., 1911, 44, 3279; A., 1911, i, 19.26 R, Engeland, ibid., 1909, 42, 2467; A., 1909, i, 651148 ANNUAL REPORTS ON THE PROGRESS OF OHEMISTRY.since synthetic 3-methyl 4-ethyl 2 : 6-dimethylcinchomeronate 27is converted by treatment with methyl iodide and moist silveroxide into methyl, not ethyl, 2 : 6-dimethylapophyllenate (11) :The new betaine notation furnishes a possible explanation of theapparent anomaly that silver apophyllenate is not converted bymethyl iodide into methyl apophyllenate, but into the isomericbetaine.28The Pyridine Group.Attention may be directed to a discussion of the separation ofpyridine, and its methyl and dimethyl derivatives from coal taroil in a state of purity.29A formula of the type (I) is suggested30 in place of the usualketonic formula for the y-pyridones, on the ground that these donot show ketonic reactions and are colourless.Although an additivecompound (11) ofOMe(111.)/o) ~ ?r /\(n*) 0 = L \l?h/N\INPhPh/N\I (1.1of N-phenylpyridone with methyl iodide may be ~repared,~l itsproperties are not those of a true ammonium iodide, since thecorresponding hydroxide reverts to the pyridone when its solutionis evaporated, as does the additive compound of the pyridonewith magnesium methyl iodide (111) when treated with acid.Further, the changes observable during the course of the reactionbetween chelidonic acid and amines suggest that this occurs inthree stages, which are thus represented :37 Compare Ann.Repom, 1918,15, 101.38 0. Murmn and E. Gottschaldt, Ber., 1922, 55, [B], 2064, 2076; A.,28 5. G. Heap, W. J. Jones, and J. B. Speakman, J . Amer. Chem. SOC.,30 A. P. Smirnoff, Helv. Chim. Actu, 1921, 4, 599; A., 1921, i, 594; Ber.,8 1 W.Borsche and I. Bonacker, Ber., 1921, 54, [B], 2678; A., i, 60.i, 861, 862.1921, 48, 1936; A., i, 171.1922,65, [B], 612; A., i, 464ORGANIC CHEMISTRY. 149co COIn the first, a t the ordinary temperature the pyrone ring is opened.In the second, a homogeneous coloured fluid melt is produced,which in the third stage passes into the colourless final product.Corresponding with (IV), a yellow p-tolyl derivative was isolated,and shown to furnish a phenylhydrazone.A comparison of the ketone (V), synthesised in the usual manner,32with the corresponding ethyl ketones, N-methyl-conhydrinoneand Asopelletierin, has shown that it resembles the latter ratherthan the former in its ready semicarbazone formation, but that itscarbonyl group is not so easily reduced to a methylene group asCH2CH, /\\/Y E 2 p 2CH, CHCOMe (vl*) H,C/\CH,(v*) H,C(,!CH*COMeNMe NHthat of either of the others. All attempts, whether by director by indirect demethylation, to prepare piperidylethanone (VI)were unsuccessful.The condensation of a-picoline methiodide with p-dimethylamino-benzaldehyde results in the formation of a product (I), whichconstitutes the most powerful sensitiser yet known for green lightfor gelatino-silver bromide photographic plates .53Interpretations of the reactions ensuing on the partial reductionof the pyridine nucleus34 have been considerably revised, as aresult of parallel investigations.Of these, perhaps the mostilluminating are those concerned with the formation and reactions32 K.Hess and W. Corleis, Ber., 1921, 64, [ B ] , 3010; A., i, 170.W. H. Mills and (Sir) W. J. Pope, T., 1922,121, 946.a4 Compare Ann. Reports, 1920, 17, 106; 1921, 18, 134160 A"UAL REPORTS ON THE PROGRESS OF CHEMIS'YRY.of dia~etyltetrahydrodipyridy1.~5 This colourless compound, whenprepared from pyridine, is accompanied by a small proportion ofan orange product, identified as diacetyldihydrodipyridyl (11).This is easily oxidised by air or by bromine to 77-dipyridyl, or itsperbromide, respectively, and may be obtained by adding aceticanhydride to the blue solution produced when dipyridyl is reducedby zinc dust and acetic acid.36 It seems not to be directly obtain-able from the tetrahydro-derivative, but is produced when this isheated with dipyridyl in acetic anhydride solution at 100" :AcN/=\/H H\/=\NAc + N/-\-/-\N ~ \=/- \=/ \-/ \-/The significance of this lies in the fact that hot solutions of thetetrahydro-compound become blue only in presence of air (whichis known to produce dipyridyl), or on the addition of dipyridyl.The blue colour therefore appears to be associated with the presencein solution of dihydrodipyridyl or a derivative.This inference isconfirmed by the composition of " dipyridyl violet chloride " (I),prepared by reduction of dipyridyl with one equivalent of chromouschloride in presence of calcium chloride :JIt will be noted that this compound differs from most quinhydronesin that the quinonoid portion is the reduced part of the molecule,and becomes aromatic by oxidation.It has been recognised that the blue solutions obtained from thebrown " benzoylpyridinium," yellow dimethyl- and clieihyl-" tetrahydrodipyridyls," and red " benzylpyridinium," most prob-ably owe their origin to similar reactions.The last compoundhas been definitely recognised as NN-dibenzyldihydro-yy-dipyridyl,but an account of this work is unnecessary, since in many respectsthe results are analogous to those just detailed. The obviousinference from the above that hydrogen atoms in the 7-positionof the pyridine nuclei of the parent compounds are essential to35 0. Dimroth and F. Frister, Ber., 1922, 55, [B], 1223, 3693; A., i, 678.36 The earlier statement, that the tetrahydro-compound is formed by thisreaction, has been withdrawn; Zoc. cit., 1223, footnote 2ORGAN10 CHEMISTRY.151the production of blue solutions has been confirmed by an examin-ation of the corresponding yy-dicollidyl and di-2 : 4-lutidyl com-Picrorocellin.Picrorocellin is the colourless mono-O-ether of 2 : 5-diketo-3 : 6-di-o-hydroxybenzyl-1 -methylpiperazine (I),38 since on treat-ment with hydrochloric and acetic acids, it is converted into paleyellow xanthorocellin (11). The constitution of this productfollows from its oxidation to benzaldehyde (and benzoic acid), and2 : 3 : 5 : 6-tetraketo-l-methylhexahydro-1 : 4-diazine (111), identicalwith the compound 39 prepared by condensation of methyloxamideand oxalyl chloride. Since, further, methylation of the secondaryamino- and the free hydroxyl groups of picrorocellin yields aninternally compensated product, it follows that this, and henceprobably also picrorocellin itself, has a trans-configuration.OH*CHPh*QH*NMe*yO + CHPh:Q*NMe-CO .+ yO*NMe*COCO-NH*t]:CHPh CO*NH- 60po~nds.37C 0-NH-CH CHPh.OH(1.1 (11.1 (111.)The Quinoline Group.Quinoline and its derivatives rapidly absorb four atomic pro-portions of hydrogen in their pyridine nuclei, when they are reducedin presence of nickel salts under pressure, but the subsequentstages of reduction to decahydro-derivatives proceed much moreThe synthesis of cinchonic and quinic acids has continued toengage attention. The preparation of cinchonic acid by decom-position of the quinoline-2 : 4-dicarboxylic acid 41 resulting fromthe condensation of pyruvic acid with isatin has been extendedto 6-methoxyisatin for the purpose of preparing quinic acid.42But the process would not seem to be as convenient as that inwhich 6-methoxyquinoline serves as a starting material.& Anotherprocess is outlined in the following scheme :slowly.40*7 B.Emmert and others, Ber., 1921, 54, [BJ, 3168; 1922, 55, [Bl, 1362,2322; E. Weitz and others, ibid., 395, 599, 2864; A., i, 179, 680, 1064, 365,470, 1186.J* M. 0. Forsfer and W. B. Ssville, T., 1922,121, 816.39 J. V. Dubsky, Ber., 1919, 52, 216; A., 1919, i, 288.40 J. v. Braun, A. Petzold, and J. Seeman, ibid., 1922, 55, [B], 3779; A*,4 1 W. Pfitzinger, J . pr. Chem., 1902, [GI, 66, 263; A., 1903, i, 53.42 J.Halberkann, Ber., 1921, 64, [B], 3079; A., i, 172.43 A. Kaufmann, ibid., 1922, 55, [B], 614; A., i, 464.1923, i, 136162 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.-3\/\NMe*C 0C0,HIn this case the elimination of the halogen atom remains to beaccomplished.aThe 2-hydroxy- and 2-phenyl-derivatives of 3-phenylcinchonicacid undergo internal condensation when treated with sulphuricacid.45As would be expected by analogy with fluorenone, the resultingketones (I) are yellow, whilst di-2-quinolyl ketone (11), preparedby hydrolysis of the condensation product of nitrosodimethyl-aniline with diquinolylmethane, is colo~rless.~~Reduction of ethyl 2 : 2’-dinitrodibenzylmalonate furnishes bis-hydrocarbostyril-3 : 3’-spiran (111), which is interesting owing tothe asymmetry of its molecular structure :W*) ‘ (V.)Accordingly, its 6 : 6’-disulphonic acid has been resolved intooptically active components by means of the quinine salts. Thesp’ro-compounds (IV) and (V) were also prepared in the courseof this investigation. 47The constitution previously attributed to the cyanines 48 has4a E. Thielepape, Ber., 1922, 55, [B],127; A., i, 271.4 6 G. Scheibe and G. Schmidt, Ber., 1922, 55, [ B ] , 3157 ; A . , i, 1190.4 7 H. Leuchs and H. v. Katinszky, ibid., 710; H. Leuchs, (Miss) E. Conrad,Farbw. vorm. Meister, Lucius, & Briining, D.R.-P. 343322; A., i, 867.and H. v. Katinszky, &id., 2131; A., i, 471, 873.Compare Ann. Reports, 1920, 17, 121ORGANIC CHEMISTRY. 163been confirmed by a synthesis of pinacyanol from quinaldineethiodide and ethyl orthoformate in presence of acetic anhydrideor zinc chloride :/\/\I I J $- (EtO),HC-OEt $- HC\/\NEtI\ / \ P H 3NEINEtI NEtThis reaction, it may be noted, is common to the benzothiazolesand to the dialkylind~lenines,~~ in which the *CH:CH* group ofthe quinoline nucleus is replaced respectively by :S and :CR,.Further, it has been shown that the absorption curves, whetherin neutral or in acid solution, of pinacyanol and of diethyliso-cyanine are almost identical in form.This is a particular case ofa valuable generalisation that the absorption curves of compounds,the relationship of which is expressed by the formulae (I) and (11),are very similar, to an extent increasing with the value of n.The same paper b0 contains a general review of the various typesof cyanines, and proposals for a comprehensive system of nomen-clature to replace the present somewhat trivial designations, andcapable of application to products in which the unsaturated carbonchain between the nuclei is prolonged, Compounds of this typehave yet to be prepared, but experiments in this direction will notbe lacking in view of the obvious interest attaching to them.The two dyestuffs, which result from the action of a base, pre-ferably pyridine, on a mixture of the alkyl iodides of benzothiazoleand its l-methyl derivative, correspond in general properties .tothe ~ y a n i n e s .~ ~ This similarity extends to their constitution, forthe yellow diethylthiocyanine iodide has been synthesised by thereactions indicated :40 Compare W.Kanig, J. pr. Chem., 1911, [ii], 84, 194; A., 1911, i, 808.61 A. W. v. Hofmann, ibid., 1887, 20, 2262; W. H. Mills, T., 1922, 121,W. Kcmig, Ber., 1922, 56, [B], 3293; A., i, 1188.455; W. H. Mills and W. T. K. Braunholtz, &id., 1489154 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.S SThe virtual tautomerism observed in the case of the isocyaninesrecurs in the thiocyanines, 52 for the same methyl diethylthiocyanineiodide (I) is obtained, whether the ethiodides of 6;- and l-methyl-benzothiazoles or of 1 : 5-dimethylbenzothiazole and benzothiazolebe condensed.The purple compounds formed simultaneously with the thiocyaninescorrespond with the carbocyanines, and are formed in a similarmanner by the linking up of two molecules of l-methylbenzo-thiazole alkyl halide through a methenyl group derived from thebenzothiazole alkyl halide.The synthesis of these thiocarbo-cyanines has been referred to above, although in this case experi-mental details are not yet available.Thioisocyanines (11) have been synthesised, and resemble theisocyanines in their general characters. 53The indenoquinolines (I) and (11) result from the condensationof o-aminopiperonal with a- and p-hydrindones, respectively. 54The anhydro-base derived from the methosulphate of (11) is purpleand therefore is written as (111), the relationship between (11)and (111) being akin to that of the colourless and coloured formsof diquinolylmethane .5562 aompare Ann.Report.8, 1920, 17, 122.63 W. T. K. Braunholtz and W. H. Mills, T., 1922, 121, 2004.64 J. W. Annit and R. Robinson, ibid., 827.6 6 Compare .Ann. Reports, 1921, 18, 117ORGANIC CHEMISTRY. 155CH CH, CHThe condensation of isatin with a-tetralone (tetrahydro-a-naphthol) in presence of potassium hydroxide is a similar reactionto that just referred to. The product, 3 : 4-dihydro-1 : 2-naphtha-cridine-14-carboxylic acid (IV), is termed tetrophane to recallits similarity in constitution to atophane (V), but the two differprofoundly in their pharmacological action. 56 The new compoundresembles strychnine in its action on the spinal cord.NH ~O*C6E4*NH2QO2HC CH, C0,HI I\/N I I\/(IV.1 (V* 1 (M. 1When indigotin is boiled with aniline, preferably in presence ofa condensing agent, reaction occurs, probably in the normal mannerbetween the carbonyl and the amino-groups :The prod~ct,~' which furnishes isatin on oxidat&, is rearrangedby warm dilute mineral acid to an isomeride, no longer oxidisableto isatin, but which on hydrolysis yields aniline and o-amino-benzoyl-5-quindoline (VI) . 58A number of 9-aminoscridines have been described, and arefound to possess bactericidal pr0perties.5~The method of separation of isoquinoline from coal tar quinoline 6odepending on the greater basicity of the former has been improved.G168 J. v. Brctun and P. Wolff, Ber., 1922, 65, [B], 3675; A., 1923, i, 143.6 7 E. Grmdmougin and E. Dessoulavy, ibid., 1909, 42, 3636, 4401; A.,6s E.Grandmougin, Compt. rend., 1922, 174, 1175; A., i, 584.69 M. L. B., Brit. Pat. 176038; A., i, 468.6o R. Weissgerber, Ber., 1914, 47, 3175; A., 1915, i, 302.1909, i, 968; 191.0, i, 73.J. E. G. Harris and (Sir) W. J. Pope, T., 1922, 121,11029166 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.A review of the attempts made to synthesise isoquinolines fromcompounds of the type (I) has led to the conclusion that successis only attained when the compound contains a system of conjugateddouble bonds, and a hydroxyl or alkyloxy-group in the @-positionto the nitrogen atom, or when such a system can be formed in thecourse of the reaction.s2It has been shown that 1-, but not 3-, methylisoquinoline con-tains a reactive methyl group, and that 4-phenyl-2-methyl- (IV), butnot 2-phenyl-4-methyl-thiazole is similarly reactive.The differenceis attributed either to the direct influence of *he double bondbetween the nitrogen atom and the carbon atom, contiguous tothe methyl group, or to the possibility which this confers of theformation of a tsutomeride, for example (III).63Alkaloids.Earlier investigations of ricinine had shown that it responded tothe tests for the presence of a glyoxaline ringY6* contained onemethylimino-groupY65 and was broken down by 57 per cent.sulphuric acid into ammonia, .carbon dioxide, and a compound,C,H,02N. The presence of a pyridine ring in the alkaloid hadpreviously been suspected,66 and it has now been shown 67 that theproduct just mentioned is a pyridone, since it is also obtained byspontaneous loss of methyl iodide from 2 : 4-dimethoxypyridinemethiodide (I).Of the two possible formulze thus indicated,(11) is adopted, because the boiling point of the compound suggeststhat it is derived from N-methyl-2-pyridone rather than fromthe 4-isomerideY and ricinine is considered to be most probablyeither (111) or (IV).62 P. Sbub, Hdv. Chim. Actu, 1922, 5, 888; A . , 1923, i, 140.O3 W. H. Mills and J. L. B. Smith, T., 1922, 121, 2724.(* E. Schulze and E. Winterstein, 2. phy8iOl. Chem., 1904, 43, 211; A.,1905, ii, 112; B. Battcher, Ber., 1918, 51, 673; A,, 1918, i, 304.66 B. BClttcher, loc. cit.66 L. Maquenne and L. Philippe, Compt. rend., 1904, 138, 606; 139, 840;*' E.Spath and E. Tschelnitz, Moruzt8h., 1921, 42, 251; A., i, 671.A., 1904, i, 339; 1905, i, 80; B. BiSttcher, loc. citORGANIC CHEMISTRY.OMe OMe157(2) CHN /A\ (1) /\/\ CH, Hi(fHK”(v-) R( I I CH(OH)--~H L H , C ~ ,\ I / / \NOf the four asymmetric carbon atoms in the general formula(V) of the cinchona alkaloids, it is already known e8 that the spatialdistribution of the groups respectively attached to (1) and (2) issimilar in each of the alkaloids, and dextrorotatory in total effect.Also, the stereoisomerism of cinchonine and cinchonidine, or ofquinine and quinidine is conditioned by the dizerent distributionround (3). Attention has now been drawn 69 to the fact that ofthe four possible reduction products of hydro~inchoninone,7~ themost dextrorotatory is dihydrocinchonine, whilst the most laevo-rotatory is dihydrocinchonidine.If the principle of optical super-position be adopted in a semi-quantitative sense, it follows thatin dihydrocinchonine, and hence in cinchonine itself, the effectsof (3) and (4) must be both dextrorotatory, whilst in cinchonidineand its dihydro-derivative they are centres of laevorotation. Theextension of these conclusions to the other aIkaloids is based on acomparison of the rotatory values of the alkaloids, their mono-chloro-derivatives, and their deoxy-derivatives. This indicatesthat quinine, dih ydroquinine, cinchonidine, dihydrocinchonidine ,and ethylhydrocupreine (optochin) are alike in configuration, butdiffer in this respect from quinidine, hydroquinidine, cinchonine,and hydrocinchonine.A conception of the absolute nature ofthe spatial distribution of the groups round each of the four carbonatoms in question is still lacking, but appears to be deducibleiffurther investigation should confirm the statement 71 that internalethers, O<-_CH>C,,H,,N,, are obtainable from hydroxydihydro-cinchonine but not from hydroxydihydrocinchonidine. For suchether-formation would seem to demand that the =CH,*CH( OH)-CHMe6 8 P. Rabe and others, Annalen, 1910, 373. 89; A., 1910, i, 417.6s H. King and A. D. Palmer, T., 1922, 121, 2577.70 Compare Ann. Reports, 1921, 18, 140.71 Compare ibid., 1920, 17, 120158 ANNUAL REPORTS ON THE PROGRESS 03 OHE~STRY.and the *CH(OH)* groups, respectively attached to (1) and (3),are on the same side of the piperidine ring structure, but on theopposite side to the methylene groups of the quinuclidine bridge.It need scarcely be pointed out that the asymmetry of the ter-valent nitrogen atom in these alkaloids does not increase thenumber of isomerides possible, because the spatial distribution ofthe groups attached to it is not independently variable.This,however, does not apply to the cincho- and quina-toxins, andcorrespondingly it is found 72 that although the conversion of thetoxins prepared from the alkaloids furnishes yields exceeding 80per cent., these only amount to 50 per cent. when synthetic toxins,presumably composed of a mixture represented by (I) and (11),are employed.The quinuclidine nucleus would seem to bc: in some way respon-,sible for the pneumococcidal properties of the cinchona alkaloids,since neither dihydroquinatoxin nor the corresponding secondaryalcohol is as efficient in this respect as dihydr~quinine.?~A revision of the results of earlier workers has shown that thequinoline nucleus is attacked when dihydrocinchonine is reducedin amyl-alcoholic solution by sodium.The three products isolated-hexahydrocinchonine, together with epimeric a- and p-hexa-hydrodeoxycinchonines-each show the reactions of secondarybases .74On the other hand, it is suggested that the quinuclidine, ratherthan the quinoline, nucleus is attacked when quinine is convertedinto an amino-oxide by treatment with hydrogen peroxide.Thisconclusion is based on the fact that the reaction does not applyto quinoline, but that similar compounds have been obtained fromquinidine, dihydrocupreine, and optochin. This argument, how-ever, does not seem very satisfactory, since cinchonine does notreact in this manner. Quinine oxide is sufficiently stable to permitof its reduction to dihydroquinine oxide.75The 5-, and, less readily, the 8-amino-groups of 5 : 8-diamino-6-methoxyquinoline are replaced by hydroxyl when the compoundis boiled with hydrochloric acid. 5 : 8-Diaminodihydroquinoline72 P. &be, Ber., 1922, 55, [BJ, 522; A., i, 361; P. Rabe, K. Kinder, and0. Wagner, ibid., 632; A., i, 361.73 M. Heiddberger and W. A. Jacobs, J . Arne?. Ohem. SOC., 1922,44,1098;A., i, 673.74 W.A. Jacobs and M. Heidelberger, ibid., 1079; A., i, 672.75 E. Speyer and A. G. Becker, Ber., 1922, 55, [BJ, 1321; A., i, 6740RQmc CHEMISTRY. 159reacts still more readily, so that apparently the intermediatehydroxyamino-compound is not isolated. But, on the other hand,5 : 8-diaminoquinoline is recovered practically unchanged.76 Thisfavourable influence of the 6-methoxy-group is also observed inthe analogous case of the hydrolysis of benzeneazo-&amino-quin0line.~7The position of the methoxy-group in harmine and harmalinehas now been conclusively fixed by the reduction of syntheticmethoxyketomethyldihydrocarboline (I) (see p. 128) in butylalcoholic solution by means of sodium to a base, which must beN-methyltetrahydronorharmine (11), since it may be similarlyobtained from norharmine methosulphate (111) :Burthermore, synthetic N-methyltetrahydronorharmine has beenoxidised by potassium permanganate in acetone soluhion to theneutral substance (IV), originally obtained by similar means fromharmaline (V), thus confirming the formulae of these two com-pounds. The neutral substance has also been reduced to N-methyl-tetrahydronorharmine. 78The oxidation of norharman methosulphate to ketomethyl-dihydrocarboline is evidence that in the free compound additionof methyl sulphate occurs on the pyridine rather than on thepyrrole nitrogen atom, in agreement with an earlier suggestion 79that the former was the more basic of the two.In accordance with the formula (I) previously suggested forrutacarpine, which accompanies evodiamine in EcOdia rutcecarpa, 80the former is almost quantitatively converted by treatment with' 6 W. A, Jacobs and M. Heidelberger, J. Amer. Chem. Soc., 1922, 44,1073; A., i, 671.7 7 Ann. Reprta, 1921, 10, 138.' 8 W. 0. Kermack, W. H. Perkin, and R. Robhaon, T., 1922, 121, 1872.70 W. H. Perkin and R. Robinson, ibid., 1919, 115, 933.60 Y. Asahha and S. May&, J . P h m . SOC. Japan, 1916, No. 416; A .1921, i, 48; compare Ann. Reports, 1921,18, 142160 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.amyl alcohol and potassium hydroxide into Z-p-aminoethylindole-3-carboxylic acid, from which 2-P-aminoethylindole itself is obtainedby means of hydrochloric acid :/\I IIM /Y /\-C02H +/\-"'1 I ICH2*CH2*NH2 I I ICH2*CH2*NH, /\-/\/ \/\/ \AdH 1 I1 II y NH\/\/\A2H2(I.) NH CH2A new isomeride of tropine has been isolated from among thebasic residues remaining after removal of ecgonine from the productsof hydrolysis of the coca alkaloids, but no constitutional formulahas been assigned to it.82 The hydroecgonidine prepared bycatalytic reduction of anhydroecgonine consists of two stereo-isorneride~.~~ It would therefore seem that the older formula 84for anhydroecgonine (I) must be replaced by (11), and this issupported by the observed exalted molecular refraction of the ethylester of anhydroecgonine as compared with that of hydroecgonidine.CH,-CH-CH*CO,H CH2-CH-C*C0,HCH2-dH-8H CH2-CH-dH,(1.1 I h e dH I @ e 8 ~ (11.1The formula attributed to scopoline 85 has been revised oninteresting stereochemical grounds. It had previously been amatter for comment that whilst not more than two opticallyactive forms of the alkaloid had been obtained,86 the productsof its hydrolysis were each known to contain asymmetric carbonatoms.s7 Further, when the asymmetry of the tropyl residue inthe alkaloid was destroyed by converting the latter into aposcopol-amine (111), the latter could not be resolved :Y. Asahina and A. Fujita, J. Pharm. SOC Japan, 1921, 863; A,, i, 47.82 J. Tr6ger and K. Schwarzenberg, Arch. Phamz., 1921, 259, 207; A.,83 J. Gadamer and C. John, ibicE., 227, 244; A., i, 167, 675.85 Compare Ann. Reports, 1920, 17, 127; 1921, 18, 143.86 H. King, T., 1919, 115, 476, 974; Ann, Reporte, 1919, 18, 117.i, 167.R. Willstiitter and W. Miiller, Ber., 1898, 31, 2655; A , , 1899, i, 178.H. Tutin, T., 1910, 97, 1793OWIANICt UHElKISTBY. 161Again, the d-phenylpropionate resulting from the reduction ofaposcopolamine consisted of only one racemate. When, however,the attempt was made to synthesise the same compound fromscopoline and d-phenylpropionyl bromide, the product was com-posed of two readily separable racemates. The remarkable con-clusion was therefore reached that the alcohol of which scopolamine(I) is the ester is probably internally compensated, but suffers a,rearrangement, when liberated by hydrolysis, into the asymmetricscopoline (11).:- CH,-CH-CH*OHCH!z*OH hH,-bH-CH/ 1 I hH2-&H-CH*OH ' li FHPh*CO*O*bH kMe I(4) (3)(a>hH*OH &Me IThese relationships are represented as follows : 88\ CH,-CH--CH0 --+ IHOdH kMe(1.1CH,-CH-CH* OH CH,-CH-CH*OH (2) p:,-g:JH I (6) bH,-CH-CH*OH (1) (1)I- ____ 0 ~(11.) (111.)The formula thus assigned to scopoline had been previouslysuggested 89 to account for its conversion into 1 : 2-dihydroxy-tropane, and for the natural occurrence of scopolamine and tropinein the same plant. In the formula (111) suggested a t the sametime for teloidine, as a concomitant of the bases just named, the1- and 5-hydroxyl groups are probably in the trans-position, sincethe formula (11) for scopoline shows that cis-hydroxyl groupewould probably give rise to an oxide ring. A fuller account hasalso been given of the products obtained by the degradation ofscopoline by exhaustive methylation.The structural relationship so frequently observed betweenalkaloids which occur together is also well illustrated by theformula? assigned to five of the seven known cactus alkaloids.Anhaline (I) has been identified with hordenine,90 whilst mezcaline(11) is known to be 8-3 : 4 : 5-trimethoxyphenylethylamine.gl Ithas now been shown 92 that N-acetylmezcaline may be convertedby the usual means into 6 : 7 : 8-trimethoxy-l-methyl-1 : 2 : 3 : 4-tetrahydroisoquinoline, from which by reduction the corresponding88 K. Hem and 0. Wahl, Ber., 1922, 55, [B], 1979; A., i, 854.89 H. King, loc. cit., p. 487.90 E. SpLth, Moncstefi., 1919, 40, 129; 1921, 42, 263; A., 1919, i, 548;Idem, ibid., 1919,40,129; A., 1919, i, 548; compare Ann. Reports, 1919,1922, i, 567.16, 123.92 Idem, ibid., 1921, 42, 97; A., i, 163.REP.-VOL. XIX . 162 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.tetrahydroisoquinoline is obtained. This, and its N-methylderivative, areCH2 CH2CH l\11eOf\(\$!H2 MeO/\/\FH,/\/NCI3, I M e O \ / NH, MeO(/\,,NHNMe, OMC Me0 QH(1.) (11.) (111.) MeCH2 CH2~ t e d " \ ~ H ,Me01 I \/\/NMeMe0 $!H OH CH,(rv.) Me (V.)respectively identical with the O-methyl derivatives of anhalonidine(111) and pellotine (IV). It therefore only remains to determinewhich of the three methoxy-groups of the synthetic compoundscorresponds with the phenolic hydroxyl in the two alkaloids. Theprobable mode of attacking this problem is indicated by thatsuccessfully adopted in the case of anhalamine (V), and indicatedin the following scheme representing the synthesis of this basefrom gallic acid : 93Again, the bases which accompany palmatine in the calumbaroot, and are separated from it by successively extracting themixture of the iodides of the bases with potassium carbonate andwith potassium hydroxide, are now shown to furnish on methyl-ation products, not only identical with each other, but also withpalmitine. The identity also extends to the tetrahydro- basesand therefore it follows that the calumba root contains besidespalmatine, phenolic bases having one or more free hydroxyl groupsE. Spiith and H. Roder, MOnUtclh., 1922, 43, 33; a,, i , 852ORGANIC CHEMISTRY. 163in place of methoxyl groups in palmatine, or else phenolic oxygencombined with complexes easily removable by hydrolysis. Itshould be noted, however, that the homogeneity of the above twobasic extracts, columbamine and iatrorhicine, is not quite certain.g4The formula previously assigned to laudanine 95 has been con-firmed by synthesis.96 This follows the course now so familiaras to be almost conventional in such cases, and furnishes anotherillustration (compare the synthesis of anhalamine, above) of thedevicc of masking a phenolic hydroxyl group throughout such asynthesis by its conversion a t the outset into an ethylcarbonato-group, from which it can be regenerated a t the conclusion.The need for a revision of the formula of corydaline has beenadmitted, and (I) is now suggested, since dehydrocorydalinc,derived by removal of four hydrogen atoms through the agencyof mercuric acetate, is found to undergo the Cannizzaro reactionwith sodium hydroxide .9OMePassing reference has already been made to an investigation ofisochondodendrine, in which considerable progress has been madetowards the determination of its constitution. But it would seemadvisable to defer a fuller account of this until one or two out-standing points have been cleared up by further investigation.Several papers have appeared on the chemistry of the morphinealkaloids and of strychnine, but these are not of a character whichmay usefully be dealt with here.J. KENNER.94 E. Splith and K. Bohm, Ber., 1922, 55, [B], 2985; A., i, 1174.95 Compare Ann. Reports, 1921, 17, 144.96 E. Spiith and N. Leng, Moncctah., 1921, 42, 273; A., i, 668.97 J. Gadamer and F. von Bruckhausen, Arch. Plmrm., 1922, 259, 246;A,, i, 675

ISSN:0365-6217    

DOI:10.1039/AR9221900060

出版商:RSC    

年代:1922

数据来源: RSC

摘要:

ANALYTICAL CHEMISTRY.THE number of analytical papers now being published has fullyreached the standard of the years before the war, and there-fore the prefatory remarks to last year’s Report are still moreapplicable to the present Report.Physical Methods.The useful process of separating the constituents of mineralsby treatment with liquids of different density has been extendedby the introduction of three colourless liquids, namely, bariumbromomercurate solution, saturated aqueous thallium formatesolution, and a mixture of aqueous solutions of thallium formateand malonate. By using these a t different temperatures a rangeof density from 3.1 to more than 5 is obtained.1There have been several new applications of spectroscopy toanalytical work. For example, it has been shown that the spectro-scope affords the most accurate means of distinguishing betweencaesium and rubidium; also, that germanium may be easilyidentified by its arc spectrum, which shows a characteristic line inthe blue region3I n a further development of a research on spectrophotornetryi t has been found that the method, when used in conjunctionwith data previously recorded, will enable the proportion of enolin keto-enol mixtures to be estimated with a fair degree of accuracy,provided it is possible to ascertain the optical constants of therespective pure constituents.5By making mixtures of pure argon with pure xenon and withpure krypton, and determining the pressure at which the spectro-photometric intensity of selected lines in the spectra of the re-spective mixtures becomes equal to that of corresponding selectedlines in the argon spectrum, i t has been found possible t o calculatethe proportions of xenon and krypton in the two mixtures.61 E.Clerici. Atti R. Accad. Lincei, 1922, [v], 31, i, 116; A., ii, 578.2 J. Missenden, Chem. News, 1922, 124, 362; A., ii, 658.3 J. Papish, ibid., 3 ; A., ii, 163.4 K. von Auwers and H. Jacobsen, Annalen, 1918, 415, 169; A., 1918,5 Idem, ibid., 1922, 426; 161; A., ii, 168.6 C. Moureu and A. Lepape, Compt. rend., 1922,174, 908; A., ii, 394.ii, 381.16ANALYTICAL CHEMISTRY. 165The difference in the colour reactions of methylfurfuraldehydeand hydroxymethylfurfuraldehyde when converted into phloro-glucides may be sharply distinguished by the use of the ultra-violetspectro~cope.~Mention may also be made of a new method of colour measure-ment based upon spectrophotometric measurements.The more recent work on nephelometry has included a studyof the cause of the deviations from the proportionality betweenthe amount of diffracted light and the concentration of colouredsols and turbidities.It is due to the selective absorption of lightby the coloured particles, and may be prevented by the use ofsuitable light filters placed between the source of light and thenephelometer .9A new type of nephelometer has also been devised in which thetwo fields are made concentric. By using two Nicol prisms, bywhich the light can be registered and regulated, in place of oneof the tube systems in this instrument, a permanent standard maybe established.10An optical method of estimating the colloidal portion of tungstenpowder has been based on the absorption of light from a quartz-mercury lamp by the solution from which the powder has sedi-mented, and the measurement of the absorption by the deflectionof a galvanometer when the light passing through the solution isreceived on a potassium photo-electric cell.llA new principle of estimating unweighable quantities of metalssuch as lead or bismuth consists in the use of the radioactive iso-topes of the metals as indicators.Since the active and inactiveisotopes, when once mixed, cannot be separated by chemicalmethods, the detection of the former by means of the electroscopeis also an indication of the presence of the latter.12Another application of the electroscopic method of analysis hasbeen its use in the estimation of thorium in monazite sand by meansof the emanation.The percentage of thorium-X is calculatedfrom the electroscope readings by means of the formulax = ATs(Tb - Tu)/T,(Tb - C),where A represents the proportion of thorium in a standard sample,T, the time of discharge of the electroscope by this standard7 J. Tadokoro, J . Coll. Agric. Hokkaido Imp. Univ., 1921, 10, 62; A.,ii, 236.8 H. E. Ives, J . Opt. SOC. Amer., 1921, 5 , 469; A., ii, 221.9 H. Bechhold and F. Hebler, Kolloid Z., 1922, 31, 7 ; A., ii, 652.10 A. A. Weinberg, Biochem. Z., 1921, 125, 292; A,, ii, 309.11 A. Lottermoser, Kolloid Z., 1922, 30, 53; A., ii, 230.l2 F.Paneth, 2. angew. Chem., 1922, 35, 549; A,, ii, 785166 ANNUAL REPORTS ON THE PROQRESS OF CHEMISTRY.sample, Tb the time of discharge by a blank sample free fromthorium, and T, by the sample under examination.13A new thermometric method of titrating acids has been devised,the solution being mechanically stirred in a vacuum tube, whilealkali solution is added at regular intervals in amounts causingthe temperature to increase by not more than 0.02". When thetemperature readings are plotted as ordinates and the number ofC.C. of alkali as abscissae, a decided change in the direction of thecurve indicates the end-point. The method not only gives resultsidentical with those given by electrometric methods, but alsoindicates other points a t which changes in the nature of the reactiontake place.14Gas Analysis.The most suitable concentration of pyrogallol solution for ab-sorption of oxygen in gas analysis has been ascertained by tabu-lating the absorptive capacities of solutions of all concentrations in aGibbs triangular diagram for the system pyrogallol, potassiumhydroxide, and water.By this means it has been found that thebest results are obtained by the use of a solution of 20 parts ofpyrogallol and 20 parts of potassium hydroxide in 60 parts ofwater. 15It has also been shown that in using acid cuprous chloride solutionas an absorbent for carbon monoxide the rate of absorption andthe stability of the reagent are increased by the addition of stannouschloride.16For the accurate estimation of hydrogen in the presence of gaseousparaffins advantage has been taken of its reducing action onpalladous chloride, the separated palladium being collected, dried,and weighed, and calculated into the equivalent amount ofhydrogen.Various absorbents have been tried for the estimation of hydrogenphosphide.The gas is completely absorbed by iodic acid solutionwithin thirty minutes, and by distilling the liberated iodine intopotassium iodide solution and titrating the liquid it is possible toestimate the phosphine. Or the phosphoric acid in the flask maybe estimated as magnesium pyrophosphate. Another method isto absorb the hydrogen phosphide in standard silver nitrate, mer-curic chloride, or gold chloride solution, and to estimate the phos-I s H.H. Helmick, J . Amer. Chem. Soc., 1921, 43, 2003; A., ii, 164.l 4 P. Dutoit and E. Grobet, J . China. physique, 1922, 19, 324; A . , ii, 578.l6 F. Hoffmann, 2. angew. Chem., 1922, 35, 451 ; A., ii, 582.l6 A. Kropf, ibid., 451; A . , ii, 657.l7 J. A. Muller and A. Foix, Bull. SOC. chim., 1922, [iv], 33, 713; A.,ii, 655ANALYTICAL CHEMISTRY. 167phoric acid in the filtrate from the precipitated silver, etc.I8 Aspecial form of absorption apparatus for this process has beendevised.lgThe absorption of carbon dioxide formed in the estimation ofminute quantities of methane may be rapidly effected in one vesselby adding gelatin solution to the baryta absorbent, the resultingscum prolonging the contact of the gases with the reagent.*OFurther particulars have been published of the method of estim-ating benzene by absorption with charcoal.21 A correction for thebenzene retained by the charcoal is found by means of a controltest .22An accurate thermometric method of estimating minute quantities(0.001 to 1 per cent.) of oxygen in hydrogen consists in passing thegas through a platinised catalyst a t 305", and measuring the risein temperature, caused by the combustion of the hydrogen, bymeans of a thermo-element connected with a galvanometer.=Another method of estimating traces of oxygen, which is par-ticularly suitable for biochemical work, is to convert the oxygen,by means of nitric oxide and sodium hydroxide, into sodium nitrite,which is then estimated colorirnetrically by means of sulphanilicacid and cc-na~hthylamine.2~It has been found that when air is used as the source of oxygenin slow combustion and explosion methods of gas analysis noappreciable error results if the time of burning does not exceedthree minutes and the platinum wire is not heated too strongly.Otherwise, an error of as much as 2 per cent.may be caused bythe formation of oxides of nitrogen.25When estimating nitrogen peroxide and nitric oxide in gasmixtures by absorption with alkali solutions it is necessary to takeinto consideration the fact that if a mist has previously developed,owing to chilling of the gas, some of the nitrogen peroxide will havebeen converted into nitric acid and nitric oxide, and that theseconstituents must be absorbed and included in the calculations.26Traces of oxides of nitrogen in air may be accurately estimatedL.Moser and A. Brukl, 2. anorg. Chem., 1921,121, 73; A . , ii, 393.L. Moser, ibid., 1922, 121, 313; A., ii, 519.2u E. Murmann, Oecrterr. Chem. Ztg., 1922, 25, 90; A., ii, 591.21 Compare Ann. Reports, 1921, 18, 149.2z E. Bed, 2. angew. Chem., 1922, 36, 332; A., ii, 591.23 A. T. Lamon and E. C. White, J. Amer. Chem. SOC., 1922, 44, 20; A.,24 H. M. Sheaff, J . Biol. Chem., 1922, 52, 36; A., ii, 682.2 5 G. W. Jones and WT. L. Parker, J . Id. Eng. Chem.., 1921, 13, 1164;* 6 C. I,. Burdick, 7 3 i ~ 7 . ~ 1922, 14, 308; A., ii, 583,ii, 311.A., ii, 223168 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.by oxidising them with sodium hydroxide solution and hydrogenperoxide, and estimating the resulting nitrate colorimetrically bythe phenoldisulphonic acidOxidation with hydrogen peroxide (perhydrol) in alkali solutionis also the basis of a method of estimating sulphur compounds ofall kinds in coal gasY28 and hydrogen peroxide is recommended asan absorbent for sulphurous acid in air.29In connexion with this branch of analysis, mention may alsobe made of a process of estimating gases in metals.A specialform of apparatus connected with a Toeppler pump is used, andthe gases collected from a weighed quantity of the metal areexamined spectroscopically and then analysed by the usualAgricultural Analysis.Considerable attention has been given to the standardisationof the methods for the mechanical analysis of soils, and a rapidmethod has been devised in which measured amounts of a sus-pension of the soil in a 0-025 per cent.sodium carbonate solutionare withdrawn a t measured intervals and a relationship (expressedgraphically) is established between the percentage of soil and therate of ~edimentation.~~ In order to render humus soils suitablefor mechanical analysis, i t is necessary to destroy the organicmatter. This may be conveniently done by heating the soil withhydrogenFor the estimation of humus in soils the carbon dioxide presentas carbonate is first removed, and the soil then oxidised withsulphuric acid and potassium &chromate, the gases from theoxidation are conducted through copper oxide and lead chromate,and the carbon dioxide is absorbed and weighed.33It has been shown that the use of a carbon factor for calculatingthe amount of organic matter in a soil is of questionable value,and that, in any case, results closer to the truth will be obtainedby taking the relationship of 50 to 52 per cent.of carbon to represent100 parts of soil, instead of 58 per cent. as at present.34The amount of moisture in soil may be calculated from the2 7 V. C. Allison, W. L. Parker, and G. W. Jones, 77.8. Bureau of Mines,Techn. Paper, 249 ; A., ii, 313.2 8 A. Klemmer, Chern. Ztg., 1922, 46, 79; A., ii, 224.8s G. Lambert, 2. anal. Chem., 1922, 61, 20; A., ii, 390.80 H. L. Simons, Chern. Met. Eng., 1922, 27, 248; A., ii, 719.81 G.W. Robinson, J . Agric. Sci., 1922, 12, 306; A., ii, 888.83 A. Gehring, 2. anal, Chern., 1922, 61, 293.34 .T. W. Read and R. H. Ridgell, Soil Sci., 1922, 13, 1 j A., ii, 540,Idem, ibid., 287; A., ii, 888ANALYTICAL CHEMISTBY. 169measurement, under specified conditions, of the resistance betweentwo carbon electrodes placed in the s0il.3~A method of estimating the acidity or basicity of a soil, and alsothe amount of soluble iron or aluminium salts, depends on extract-ing the soil with alcoholic potassium thiocyanate solution, andtitrating the extract with standard alcoholic alkali or acid. Theuse of logwood enables a colorimetric estimation of aluminium tobe made.36Further evidence has been adduced of the untrustworthinessof citric solubility as a criterion of the agricultural value of mineralphosphates, the amounts of extract obtainable varying with theconditions.37 A modified method of estimating phosphoric acidhas been devised, in which the precipitation with ammoniummolybdate is effected in the cold, and the precipitate ultimatelydried a t 120" and weighed.Less variation in composition thusresults than in the case of precipitates obtained in the usual way.38In a combined method of estimating total nitrogen, nitric nitrogen,and nitrous nitrogen in fertilisers, the total nitrogen is first estim-ated after reduction with ferrum redactum ; the nitrites are removedby distillation as methyl esters, the residual nitrates reducedas before, and the ammonia distilled.39 The digestion with acidin the Kjeldahl flask may be greatly accelerated by the additionof Eercurous iodide, which is much more effective than mercuryor other mercury salts.40A simple method of overcoming the difficulty of estimatingguanidine when guanylcarbamide is present as an impurity is toprecipitate the guanidine as picrate from a solution of sodiumhydroxide, leaving the guanylcarbamide picrate in solution.41The conditions under which triketohydrindene (ninhydrin) can beused as a quantitative colorimetric reagent for the estimation ofamino-acid nitrogen have been worked out, and it has been shownthat histidine is the only amino-acid which gives a colorationdiffering slightly from the ~tandard.~2Organic Analysis.QuaEitative.-A general reaction enabling fatty acids of theacetic series to be detected has been found in the formation of their35 T.Deighton, J . Agric. Sci., 1922, 12, 207.38 R. H. Cam, J . Id. Eng. Chern., 1921, 13, 931; A , , ii, 172.37 J. F. Tocher, J . Agric. Sci., 1922, 12, 126; A., ii, 526.38 A. W. Clark and R. F. Keeler, J . A88oc. Otf. Agm'c. Chem., 1921, 5, 103;38 F. Mach and F. Sindlinger, 2. angew. Chern., 1922, 35, 473; A., ii, 783.40 M. and I. Sborowsky, Ann. Chirn. awl., 1922, 4, 266; A., ii, 703.41 A. H. Dodd, J . SOC. Chem. Ind., 1922, 41, 4 4 5 ~ ; A., ii, 536.42 H. Riffart, Biochem. Z., 1022, 131, 78; A., ii, 718.9.. ii, 84.U 170 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.double sodium uranyl salts, which form characteristic micro-crystalline precipitates.43Other microchemical group reagents are iodic acid, which yieldsdistinctive precipitates with alkaloids and organic bases,P4 andpicric acid, which, under standard conditions, forms crystallinepicrates of different form with vegetable alkaloids.45 Verona1 andother hypnotics derived from barbituric acid form crystallinedixanthyl derivatives of various melting points, whereas otherhypnotics do not react in this way with xanthhydr01.~6A stable modification of Schiff's reagent for aldehydes has beenprepared from rosaniline hydrochloride and sodium hyposulphite.It can be heated to accelerate the reaction withThe phenol test for formaldehyde is not trustworthy when appliedto the distillate from oxidised spirits and tinctures.A solutionof guaiacol or apomorphine in concentrated sulphuric acid givesmore definite results, The former reagent gives a dark redcoloration with formaldehyde, and the latter a distinctive pre-cipitate .48The well-known colour reaction of liver oils with sulphuric acidhas been shown to stand in some relationship to the vitamin con-tent of the oil, and the test has been applied quantitatively bya method of dilution until the colour is no longer produced.49Liquid paraffin (32.) is a suitable diluting agent for thispurpose. 60A new test for carbohydrates has been based on the formationof acetal, identified by its blue fluorescence and by the formationof 3-hydroxy-2-methylquinoline. The acetal reaction is given byall the common sugars and by dextrin, but not by glycerol, starch,or glycogen.51When sucrose is boiled with a saturated solution of ammoniumnickel sulphate and a few drops of sulphuric or hydrochloric acid,it gives a distinctive red coloration.52 Another test for sucrose inthe presence of dextrose has been based upon the fact that theJ. Barlot and (Mlle) M. T. Brenet, Compt. rend., 1922, 174, 114; A.,ii, 167.44 L. Rosenthaler, Schweitz Apoth. Ztg., 1921, 59, 477; A., ii, 327.4 5 B. E. Nelson and H. A. Leonard, J . Amer. Chem. SOC., 1922, 44, 369;A . , ii, 327.R. Fabre, J . Pharm. Chim., 1922, [vi], 26, 241; A., ii, 795.4 7 E. Wertheim, J . Amr. Chem. SOC., 1922, 44, 1834; A., ii, 793.(* B. Peyl, G. Reif, and A. Hmner, Chem. Ztg., 1021, 45, 1220; A., ii, 94.4e J.C. Drummond and A. F. Watson, AnaEyst, 1922, 47, 341; A . , ii, 665.so H. D. Richmond and E. H. England, ibid., 431; A., ii, 792.61 0. Baudisch and H. J. Deuel, J. Amer. Chem. SOC., 1922, 44, 1585;62 F. Krys, Ocslerr. C'~LCIIL. Ztg., 1921, 24, 141 ; A., ii, 233.A . , ii, 664ANALYTICAL CHEMISTRY. 171former is soluble and the latter insoluble, in hot ethyl acetate.=Lsevulose may be detected in the presence of aldoses by the factthat, after treatment with iodine solution and then with sodiumhydroxide, it gives a red coloration with Fehling’s solution withinfour minutes, whilst dextrose does not react until after five minutes’heating. 54An acidified solution of benzidine hydrochloride gives an orangecoloration with ligneous tissue, and since starch can be stainedwith iodine in the same section, the reagent will be of value inbiochemical w0rk.5~In this connexion mention should also be made of a qualitativetest for tannin based on its fixation on gold-beater’s skin, whichcan then be stained with dilute ferric chloride solution.56An acidified solution of pnitroaniline hydrochloride, decolorisedwith sodium nitrite, has been found to be a sensitive reagent forphenols, which, when treated with i t and with excess of sodiumhydroxide, give colorations ranging from salmon pink to ruby-red,according to the quantity of phenol present.The test will detect1 part of ordinary phenol in l,000,000.57A method of distinguishing between phenacetin and acetanilidedepends on the difference in the colorations given by the twosubstances when hydrolysed with sulphuric acid and oxidised withpotassium dichromate .58Traces of pyridine may be detected by the formation of a red,crystalline compound, 1 -anilinodih ydropyridinium phenyl bromide,on hreatment with aniline in the presence of water and cyanogenbromide.59 The test is capable of detecting 1 part of pyridine in350,000 parts of water.60A new method of estimating the pyrimidine, thymine, has beenbased on its oxidation into carbamide, acetylcarbinol, and pyruvicacid, and identification of thc pyruvic acid by converting it intoindigotin.61Quantitative .-There have been several contributions to themethod of ultimate analysis. Thus it has been shown that in thewet combustion of organic compounds good results are obtained63 L.A. Congdon and C. R. Steward, J . Ind. Eng. C‘hem, 1921, 13, 1143;A . , ii, 233.54 I. M. Kolthoff, CJzem. WeeMad, 1922, 10, 1 ; A., ii, 166.5 5 C. van Zijp, Pharm. Weekbhd, 1921, 58, 1539; A., ii, 94.5 6 E. Atkinson and E. 0 Hazleton, Biochem. J., 1922,16, 516; A . , ii, 593.J. Moir, J . S. African Chem. Inst., 1922, 5, 8; A., ii, 321.5 8 L. Ekkert, Pham. Zentr.-h., 1921, 82, 735; A., ii, 169.5s A. Goris and A. Larsoimeau, BulE. Soc. P?mrmacoE., 1921, 28, 495; A . ,6n I!’. Lelmer, C‘Imm. Zlg., 1922, 46, 877; A., ii, 795.61 A. Baudisch and T. B. Johnson, Ber., 1922, 55, [B], 18; A., ii, 238.ii, ‘795.a* 172 ANNUAL REPORTS ON THE PROGRESS OB CHEMISTRY.by the use of a mixture of silver chromate and sulphuric acid itsthe oxidising agent.62 The method has its drawbacks, however,for it is only applicable to certain types of compounds, such assugars not containing a methyl group attached directly to a carbongroup.63 The oxidising action of the sulpho-chromic mixture maybe increased by the addition of chromic oxide, and the scope of themethod thus extended. 64A volumetric method of estimating carbon and hydrogen is topass the gaseous products of the combustion first over a sub-stance, such as chloronaphthyloxychlorophosphine, which yieldshydrogen chloride on hydrolysis, and then into standard barytasolution, which is afterwards titrated with standard hydrochloricacid. The carbon dioxide is then removed from the baryta solu-tion after addition of 'excess of acid, and the residual solutionagain titrated, this time with standard baryta solution.65For the direct estimation of oxygen the organic substance isheated in a current of hydrogen, and the water formed in thehydrogenation collected and weighed.The method is unsuitablefor nitrogen compounds, which yield ammonia on hydrogenation.66A rapid method of estimating chlorine consists in absorbing theproducts of combustion in water and titrating the absorbed chloridewith a mercuric salt, with the use of sodium nitroprusside asindicator.67The low results obtained by the Knecht-Hibbert method ofreduction in the estimation of the nitro-groups in certain aromaticcompounds has been shown to be due to chlorination reactions.The difficulty can be overcome by using titanous sulphate insteadof titanous chloride for the reduction.68Nessler's reagent may be used, not only for the characterisationof aldehydes and ketones, but also for the estimation of certainaldehydes, the iodine liberated in the reaction being titrated withthiosulphate. 69 Another method which is applicable to variousaldehydes and ketones is based on the hydroxylamine method ' 0 ofestimating citral.71sa L. J. Simon, Cornpt. rend., 1922, 174, 1706; A., ii, 593.63 L. 3. Simon and A. J. A. Guillaumin, ibid., 175, 525; A., ii, 867.434 L. J. Simon, ibid., 768; A., ii, 868.66 J. Lindner, Ber., 1922, 55, [ B ] , 2025; A., ii, 657.66 R. ter Meulen, Rec. tmv. chirn., 1922, 41, 509; A., ii, 717.67 E.Votocgk, Chem. Listy, 1922, 16, 248; A., ii, 863.68 T. CalIan and J. A. R. Henderson, J . SOC. Chem. Id., 1922, 41, 1 5 7 ~ ;69 J. Bougault and R. Gros, J . Pham. Chirn., 1922, 26, 5; A., ii, 666.70 A. H. Bennett, Analyst, 1909, 34, 12; A., 1909, ii, 192.A , , ii, 524.A. H. Bennett and F. K. Donovan, ribid., 1922, 47, 146; A., ii,635ANALYTICAL CHEMSTRY. 173A direct method of estimating acetaldehyde is to treat the solu-tion with excess of an alkaline ammoniacal silver solution andto titrate the reduced silver with ammonium thiocyanate solution. 72A rapid colorimetric method has also been based on the fack thatacetaldehyde gives a yellow coloration with benzidine hydro-chloride.73 An analogous method fur estimating furfuraldehydedepends on the coloration which it gives with orcin01.~~The conditions affecting the quantitative estimation of reducingsugars by means of Fehling's solution have been studied and meansfor avoiding some of the errors in the current methods have beendevised.75 It has been found that sucrose is slowly hydrolysedby Pehling's solution to an extent depending on the conditions,and that a blank estimation should therefore be made.76A new method of estimating sucrose consists in heating thesugar with lime and water a t 60-SO", and polarising the solution,in which sugars other than sucrose will have been destroyed.77The use of invertase for the estimation of sucrose has also beenrecommended.78 Numerous errors are involved in the estimationof sugar in urine by fermentation with yeast. They may bereduced to some extent by sterilisation and precipitation of carbon-ates in the urine with calcium chloride.7BThe estimation of anthraquinone by the method of Lewisinvolves certain filtration difficulties ; these may be avoided byusing a volumetric method of estimation.81A gravimetric method of estimating phenanthrene is based onits oxidation by means of iodic acid to phenanthraquinone, whichis then precipitated as toluphenanthrazine by means of 3 ; 4-tolylene-diamine .A critical survey of the various methods of estimating alkaloidshas been made and the conclusion drawn that, of the gravimetricmethods, only precipitation with picric acid, phosphotungstic orsilicotungstic acid or with picrolonic acid gives serviceable results,whilst of the volumetric methods titration with standard acid is7a W.Stepp and R. Fricke, 2. physiol. Chem., 1921, 116, 293; A., ii, 236.75 N. K . Smitt, Bull. Bur. Bio-Techn., 1922, No. 6, 117; A., ii, 402.74 P. Fleury and G. Poirot, J . Pharm. Chim., 1922, [vii], 26, 87; A., ii, 666.F. A. Quisumbing and A. W. Thomas, J . Aoner. Chem. Soc., 1921, 43,1503 ; A., ii, 92.76 E . CanaIs, Bull. SOC. chim., 1922, fiv], 31, 683; A., ii, 592.7 7 A. Behre and A. During, 2. Untet-8. Nahr. Genussm., 1922, 44, 6 5 ; A , ,78 T. S. Harding, Sugar, 1921, 23, 546; A,, ii, 167.ii, 790.C. Lange, Berlin Klin. Woch., 1921, 68, 957; A., ii, 93.H. F. Lewis, J. Ind. Eng. Chem., 1918, 10, 425; A., 1918, ii, 338..O.A. Nelson and C. E. Seaseman, &id., 1922, 14, 956; A, ii, 882.82 A. G. Williams, J . AM. Chm. Soo., 1921, 48, 1911; A., ii, 90174 ANNUAL REPORTS ON THE PEOGRESS OF CHEMISTRY.the most trust worth^.^^ Caffeine gives an insoluble precipitatewith’silicotungstic acid and may be added to the list of alkaloidswhich can be estimated by means of that reagent.84New methods of estimating morphine, codeine, and narcotinein Indian opium have been described,s5 and 8 method of estim-ating meconic acid in opium, based on its separation as calciummeconate. 86Considerable attention has been given to the estimation of uricacid, and various modifications and colorimetric methods have beensuggested, including one in which an arsenotungstic acid resgentis used 87 in place of the original phosphotungstic acid reagent ofFolin and Denis.88Inorganic Analysis.Qualitative.-A scheme for separating metals by the use ofsodium sulphidc instead of hydrogen sulphide has been devised,the reagent being added to the hydrochloric acid solution, whichhas previously been neutralised with sodium carbonate and boiledwith dilute sodium hydroxide solution.The resulting precipitatemay contain the sulphides, hydroxides, and carbonates of onegroup of metals, and the filfrate the sulphides of another gro~p.8~In another scheme of separation no sulphur compounds are used,but nascent hydrogen is produced, as in the Marsh test, in thehydrochloric acid solution. A group, which may contain silver,mercury, lead, bismuth, copper, cadmium, platinum, gold, tin,antimony, and arsenic, is thus pre~ipitated.~OA new reagent for microchemical analysis has been found incasium chloride, which forms characteristic double chlorides witha large number of metals.9lAnother sensitive reagent, giving distinctive colorations withcertain metals, is a mixture of resorcinol solution and ammonia.02In addition to these group reagents, several useful tests forindividual anions have been published.For example, the Kastle-Meyer reagent (an alkaline solution of phenolphthalein decolorised83 P. Herzig, Arch. €’ham., 1922, 259, 249; A,, ii, 538.84 A. Axadian, Bull. SOC. chim. Belg., 1922, 31, 15; A., ii, 237.8 5 J. K. Rakshit, Amzyst, 1921, 46, 481; A., ii, 96.8 6 H.E. Annett and I$. N. Bose, ibid., 1922, 47, 387; A., 5, 791.87 J. L. Morris and A. G. Macleod, J. Biol. Chem., 1922, 60, 5 5 ; A., ii, 328.8 8 0. Folin and W. Denis, ibid., 1913, 13, 469; A., 1913, ii, 162.G. Vortmann, Boll. Sci. Tech., 3, [No. 51; A., ii, 653.90 V. Macri, Boll. Chim. farm., 1922, 61, 417; A., ii, 779.91 H. Ducloux, Anal. Asoc. Quirn. Argentha, 1921, 9, 215 ; A., ii, 77.g2 Lavoye, J. Pham. Belg., 1921, 3, 889; A., ii, 779ANALYTICAL CHEMISTRY. 176by boiling with zinc powder) gives a pink coloration with a solutioncontaining 1 part of copper in 100 millions.93Betltendorff's test for arsenic (reduction with stannous chlorideand hydrochloric acid), when applied as a microchemical test, isten times as sensitive as the Marsh test ; 94 and a solution of potass-ium thiocyanat,e will detect 1 part of osmium per million whenshaken with the solution of the osmium salt and with ether, theethereal layer assuming a blue c o l ~ r a t i o n .~ ~A microchemical test for tungsten has been based on the form-ation of crystals of ammonium paratungstate when tungstic acidis treated with strong ammonia solution.96For the detection of traces of uranium advantage has been takenof the fact that on treating a nitric acid solution of the metal withan excess of granulated zinc, a yellow deposit, apparently U03,2H,0,is formed on the zinc.97A reaction enabling magnesium to be separated from phosphatein an ammoniacal solution consists in the formation of the yellowinsoluble compound, ( C9H6ON),Mg,4H,O, on treating a suspensionof magnesium hydroxide with an aqueous solution of 8-hydroxy-quinoline sulphate.The precipitate, which forms characteristicmicro-crystals, is given by a solution of 1 part of magnesium inThe sensitiveness of the various tests for strontium has beenstudied, and it has been found that the reaction with sulphuricacid is capable of detecting the smallest amount (1 : 125,000), theaddition of alcohol increasing the sensitiveness to 1 : 1,400,000.99Theseinclude one for fluorine, which consists in the formation of oilydrops when the substance is heated at 90" with sand and sulphuricacid in a test-tube.l&uantitatiue.-Numerous contributions have been published onthe methods of determining hydrogen-ion concentration, and inparticular on the applicability of various coloured indicators.The wide range, both in the acid and alkaline directions, of xylenol-blue recommends it as preferable to thymol-blue for chemicaland biochemical work.2 Phenol-red, on the other hand, is too25,000.9*Only a few new tests for kations have been published.93 P.Thomas and G. Carpentier, Compt. rend., 1921, 175, 1082; A., ii, 86.94 H. Schencher, Monat8h., 1921, 42, 411 ; A., ii, 626.6 5 M. Hirsch, Chem. Ztg., 1922, 46, 390; A., ii, 459.Q6 J. A. M. van Liempt, Z . anorg. Chem., 1922, 122, 236; A., ii, 787.97 H. D. Buell, J . Id. Eng. Chem., 1922, 14, 593; A., ii, 690.Q* C. T. Marner, Pharm. Zentr.-h., 1922, 63, 399; A., ii, 669.QQ 0. Lutz, 2. anal. Chem., 1921, 60, 433; A., ii, 227.B.Fetkenheuer, Wiss. Ver68t. Siemens-Konzem, 1922, 1, 131, 177;A . , ii, 666.2 A, Cohen, Biochem. J., 1922, 16, 31; A., ii, 387176 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.greatly affected by the proportion of salts in the liquid to be asuitable indicator under all condition^.^ In the case of sodiumchloride and potassium chloride the corrections to be applied for awide range of proportions of either salt have been ascertained fora number of indicator^.^By using mixtures of coloured salts (for example, ferric chlorideand cobalt nitrate) in certain proportions as standards for thecomparison of the colorations obtained with standard indicators,it is possible to determine the hydrogen-ion concentration withoutthe use of buffer solutions.5Greater accuracy is obtainable by the use of mixed indicatorsand titrating the liquid to a definite tint than is possible by takingthe first colour change as the end-point of the titration.6 Anextended series of such mixed indicators, some of which are par-ticularly suitable for use with coloured liquids, has been drawnIn connexion with this part of the subject it may be mentionedthat symmetrical diphenylguanidine has been suggested as an idealacidimetric standard.8X new acidimetric method ofaestimating copper depends on itsprecipitation as the salt, CuS0,,4NK3, by means of alcohol, andtitration of a solution of the precipitated salt with standardacid.gThus,a rapid method of estimating chromium in nickel-chromium steelis based on its oxidation with potassium permanganate in sulphuricacid solution.loA convenient method of estimating chlorine-ion in the presenceof iodine-ion consists in precipitating them as silver salts andtreating the precipitate with a measured excess of standard potass-ium ferrocyanide solution. This reacts only with the silver chloride,forming an insoluble silver potassium ferrocyanide, which is filteredoff, and the excess of ferrocyanide titrated with permanganate.1°An oxidation method of estimating sulphides depends on theinteraction of sodium sulphide and ferric sulphate and titration ofthe resulting ferrous sulphate with permanganate after neutral-up.'Several new oxidimetric methods have been described.8 A. Massink, €'harm.Weekblad, 1921, 58, 1133; A., ii, 307.6 I. M. Kolthoff, Rec. trav. chim., 1922, 41, 64; A., ii, 222.5 Idem, Pharm. Weekblud, 1922, 59, 104; A., ii, 222.6 J. L. Lizius and N. Evers, Analyat, 1922, 47, 331; A,, ii, 664.7 A. Cohen, J . Amer. Chem. SOC., 1922, 44, 1851; A,, ii, 780.8 C. A. Carbon, a i d . , 1469; A., ii, 654.@ S. Minovici and A. Jonescu, Bul. SOC. Chim. Romdnia, 1921, 3, 89; A.,10 G. B. Bonino, Gazzetta, 1921, 51, ii, 261; A , , ii, 78.ii, 162ANALYTICAL CHEMISTRY. 177isation with alkali carbonate.ll In another oxidation method thesulphide is converted into sulphate by means of alkaline sodiumhypobromite, the excess of which is estimated iodometrically.12Dithionates resist the action of cold alkaline oxidising agents,and so may be differentiated from most other sulphur salts.Theyare decomposed, however, when heated with acid, and a methodof estimating them is based on conducting the resulting sulphurdioxide into iodine s01ution.l~A solution of a bromatc in strong hydrochloric acid will effectthe quantitative oxidation of hydroxylamine and hydrazine, andthe excess of bromate may be titrated. By then measuring thevolume of nitrogen liberated from the hydrazine, the two substancescan be estimated in the presence of each other.14Further methods involving the use of cadmium as a reducingagent have been described.15 For example, uranyl salts may beestimated by reduction with cadmium to uranous salts, followedby titration of the solution with permanganate. Vanadic acid isalso quantitatively reduced.16 In like manner, chlorates can bereduced to chlorides, and columbium estimated by reduction in acadmium tube in the presence of ammonium molybdate or vanadateor of titanium sulphate, and subsequent titration with perman-ganate.Analogous use of liquid amalgams of cadmium and of zinc havealso been described.ls These can be used for the volumetric estim-ation of molybdenum, uranium, etc.,lg for the reduction and differ-ential titration of solutions containing two metals such as iron,titanium, or uranium, and for the estimation of chloric, bromic,and iodic acids.*OMetallic mercury is a suitable reducing agent for estimatingvanadic acid in the presence of uranic and arsenic acids, which arenot reduced by mercury.2111 P.P. Budnikoff and K. E. Krause, 2. anorg. Chem., 1922, 122, 171;A., ii, 782.14 H. H. Willard and W. E. Cake, J. Amer. Chem. Soc., 1921, 43, 1610;A., ii, 80.A. Fischer and W. Classen, 2. angew. Chem., 1922, 35, 198; A., ii, 453.I* A. Kurtenacher and J. Wagner, 2. anorg. Chem., 1921, 120, 261;l5 Compare Ann. Reports, 1921, 18, 158.16 W. D. Treadwell [with M. Blumenthal and with M. Hooft], HeZv. Chim.l7 W. D. Treadwell and others, ibid., 806; A., ii, 780.la N. Kan6, J . Chem. Soc. Japan, 1922, 43, 173; A., ii, 519.1s Idem, &id., 333 ; A., ii, 529.2O Idem, ibid., 544; A., ii, 721.21 L. R. W. McCay and W. T. Anderson, J , Amer. Chem. Soc., 1922, 44,A , , ii, 312.Acta, 1922, 5, 732; A , , ii, 788.1018; A,, ii, 530178 ANNUAL REPORTS ON THE PROGRESS OF OHEMISTRY.The use of potassium ferricyanide has been shown to give accurateresults in the standardisation of thiosulphate solutions for iodo-metry.22 A new iodometric method of estimating copper hasbeen based on the oxidation of a cuprous salt with iodine, theexcess of which is afterwards titrated.The copper is first con-verted into cuprous t h i o ~ y a n a t e . ~ ~ Hydrogen peroxide or nitricacid cannot be used for the oxidation of cuprous copper in presenceof ferrous iron, and in such cases it is best to precipitate the ironfrom a hot ammoniacal solution by means of a current of air, andto use the filtrate, after removal of the ammonia, for the iodometricestimation of the copper.24The influence of atmospheric oxygen in liberating iodine fromhydriodic acid leads to erroneous results in the iodometric estim-ation of arsenic acid.It may be prevented by adding sodiumhydrogen carbonate before the potassium iodide, and having onlya minimum amount of hydrochloric or sulphuric acid present.25Good results are obtained in the estimation of arsenic or anti-mony sulphide by treating their sodium hydroxide solution withiodine solution containing acetic acid and sodium acetate, andtitrating the excess of iodine. Atmospheric oxidation is sufficientlychecked by the addition of a small amount of gelatin.2sWhen a sulphur compound is heated with powdered iron in theabsence of air, the whole of the sulphur is liberated as hydrogensulphide, which may be collected in zinc sulphide solution andestimated iod~metrically.~~These in-clude a method of estimating colloidal gold,28 of estimating vanadiumin steel by means of the coloration given by vanadium pentoxidewith hydrogen peroxide,29 of estimating manganese in steel andores by oxidising it to the compound H,MnO,, an alkaline solutionof which is ye310wish-brown,30 and of estimating antimony incopper 31A colorimetric method of estimating phosphorus in steels is basedon the blue coloration given by a hot solution of thiosulphate withammonium pho~phomolybdate,~~ and another method for phos-Several new colorimetric methods have been devised.z2 I.M . Kolthoff, Pharrn. Weekblad, 1922, 59, 66; A,. ii, 224.2s R. Lang, 2. anorg. Chem., 1921, 120, 181; A., ii, 318.24 A.Wsber, 2. angew. Chem., 1922, 35, 336; A., ii, 588.25 L. Rosenthaler, 2. anal. Chem., 1922, 61, 222; A., ii, 584.26 F. Nikolai, ibid., 257; A., ii, 585.27 L. Losana, &om. Chim. Ind. Appl., 1922, 4, 204; A., ii, 582.28 J. A. Muller and A. Foix, Bull. Soc. chim., 1922, [iv], 33, 717 ; A., ii, 662.29 A. Kropf, 2. angew. Chem., 1922, 35, 366; A , , ii, 690.30 J. Heslinga, Chem. Weekblad, 1922, 19, 302; A., ii, 660.3l B. S. Evans, Analyst, 1922, 47, 1; A., ii, 231.32 L. Losana, &om. Chim I d . Appl., 1922, 4, 68; A., ii, 392ANALYTICAL CHEMTSTRY. 179phorus on the coloration given by phosphates when boiled withammonium vanadate and treated with ammonium molybdate .33In separating arsenic from tungsten by volatilisation in acurrent of air at loo", adsorption of arsenic trichloride may beprevented by bringing the tungstic acid into the disperse conditionby treatment with pyrogallol (which is subsequently removed), orby adding glacial acetic acid prior to the addition of the hydro-chloric acid and methyl Hydrolysis of the arsenictrichloride may be remedied by the addition of a salt, such aspotassium bromide, which is readily soluble in water but dissolveswith difficulty in strong hydrochloric acid.Successive smalladditions of concentrated hydrochloric acid will also prevent thehydroly~is.~6 In the presence of nitrites and nitrates the dis-tillation method of estimating arsenic may give erroneous results,owing to the formation of nitrosyl chloride.This may be pre-vented by using hydrazine sulphate with sodium bromide as thereducing agent, and so simultaneously reducing nitrates, etc., tonitrogen .36Minute quantities of arsenic may be quantitatively separatedfrom germanium by treating the solution with a large excess ofhydrofluoric acid prior to precipitation with hydrogen sulphide.Fluorogermanic acid is formed and is not precipitated by hydrogensulphide.3'A quantitative estimation of manganese has been based on itsprecipitation as manganous. iodate, which is dried a t 100" andweighed.38Selenium oxychloride has been used as a reagent for the separ-ation of columbium and tantalum,39 and for the separation ofmolybdenum trioxide from tungsten tri~xide.~OAnother method of separating small amounts of molybdenumfrom tungsten is to convert the molybdenum into xanthate, whichcan then be extracted with hot chlor0form.~1Aluminium can be separated from iron by means of o-phenetidine,but the iron must be in the ferrous condition, since ferric salts givea precipitate with the reagent.4233 G.Mieson, Bull. Soc. chim. Belg., 1922, 31, 222; A., ii, 78,34 L. Moser and J. Ehrlich, Ber., 1922, 55, [B], 430; A., ii, 314.35 Idem, ibid., 437; A , , ii, 316.36 J. J. T. Graham and C. M. Smith, J . Ind. Eng. Chem., 1922, 14, 207;37 J . H. Miiller, J . Amer. Chem. SOC., 1921, 43, 2549; A., ii, 320.38 S. Minovici and C. Kollo, Chim. et Ind., 1922, 8, 499; A., ii, 787.39 H. B. Merrill, J . Amer. Chem. SOC., 1921, 43, 2378; A., ii, 230.40 Idem, ibid., 2383; A., ii, 229.4 1 D.Hall, ibid., 1922, 44, 1462; A., ii, 660.42 K. Chalupny and K. Breisch, 2. angew. Chem., 1922,35. 263; A,, ii, 688.A,, ii, 314180 ANNUAL REPORTS ON !l!HE PROQRESS OF CHEMISTRY.A suitable method of estimating uranium has been based on itsextraction from the mineral by means of a mixture of glacial aceticacid and nitric acid.&Etectrochemical Analysis.Among the apparatus for electrometric titration devised duringthe year mention may be made of a continuous-reading apparatusfor the determination of hydrogen-ion concentration,u and of anapparatus in which the electrode vessel is attached to a rotatingstirrer and carries a small bulb suitable for the preparation of acalomel electrode.45It has been shown that errors in the conductometric method ofprecipitation are mainly due to excessive solubility of the pre-cipitate, to the precipitate not being constant in composition, andto errors in determining the conductivity; and means of avoidingthese errors have been pointedA simple method of electrometric titration for acidimetry oralkalimetry consists in the use of a number of constant and re-producible electrodes which are equivalent to hydrogen electrodes.These are especially useful when it is required to titrate a solutionto an end-point of definite hydrogen-ion c~ncentration.~~The use of a silver cathode with an anode of platinum alloyedwith iridium or rhodium has been recommended for the rapiddeposition of copper and zinc under specified conditions, and leadmay be deposited as peroxide on the anode or as metal on thecathode according to the conditions of electr~lysis.~~An iodine electrode may be conveniently used in numerouspotentiometric estimations, such as the titration of iodides withsilver nitrate, and the analysis of mercuric chloride, thallous salts,etc., but it is unsuitable for the estimation of lead or bismuth.49In most cases the end-point of a titration with silver nitrate isindicated by the solubility of the silver compound, and the methodgives good results with chlorides, bromides, iodides, and manyother salts.50The use of lead nitrate in electrometric titration gives accurateresults with iodides in the presence of chlorides and bromides, andfor the estimation of certain organic salts.514s W.W. Scott, J . I d . Eng. Chem., 1922,14, 631; A., ii, 788.44 H. Goode, J . Amer. Chem. SOC., 1922, 44, 26; A., ii, 307.4 5 C. A. Waters, J . SOC. Chern. Ind., 1922, 41, 337r; A,, ii, 862.413 I. M. Kolthoff, 2. anal. Chem., 1922, 61, 171; A., ii, 462.*' P. F. Sharp and F. H. MacDougall, J . Amer. Chem. Soc., 1922,44, 1193;A. Kling and A. Lsssieur, Ann. Chim. Analyt., 1922, 4, 171 ; A., ii, 687.A., ii, 579.49 I. M. Kolthoff, Rec. trav. chim., 1922, 41, 172; A,, ii, 388.6o Idern, 2. anal. Chem., 1822, 61, 229; A,, ii, 581,61 Idem, aid., 369; A,, ii, 181ANALYTICAL CHEMISTRY. 181Halogen-ions may also be accurately titrated with mercuricperchlorate, but only separately and not in admixture.52When titrating ferrocyanides in acid solution with potassiumpermanganate solution, the end-point may be sharply obtainedby an electrometric method,63 but it is essential that sufficientacid, preferably hydrochloric acid, should be present to preventthe precipitation of manganese ferr~cyanide.~~ On the otherhand, when using ferrocyanide for the titration of certain metals,such as cadmium, zinc, or lead, the sharpness of the end-point isaffected both by the insolubility of the resulting ferrocyanide of theheavy metal and by the nature of the alkali metal present.55In the electrometric estimation of uranium by oxidimetrictitration of the reduced uranium salt it is necessary to take intoaccount that there are two changes in the oxidation potential, thefirst corresponding with the formation of quadrivalent, and thesecond with that of sexavalent uranium.56An amalgam of zinc gives good results in the reduction of com-pounds of metals such as iron, molybdenum, vanadium, anduranium, prior to electrometric titration with potassium per-manganate solution.57 Another oxidimetric method consists inreducing a cupric salt with titanium trichloride and subsequentlytitrating the cuprous salt with standard dichromate or potassiumbromate solution in an atmosphere of carbon dioxide.58A series of test experiments has shown that traces of sulphatemay be accurately estimated by conductometric titration withbarium chloride, the addition of alcohol being an advantage. 69The conductometric method has also been applied to the titrationof solutions of hydrofluosilicic acid,60 to the titration of acids andphenol in alcoholic solution by means of an alcoholic solution ofsodium ethoxide,'jl and to the titration of azo-dyestuffs and nitro-compounds.62C. AINSWORTH MITCHELL.G2 I. M. Kolthoff, 2. and. Chem., 1922, 61, 332; A., ii, 666.53 E. Miiller and H. Lauterbach, 2. anal. Cheh., 1922, 61, 398 ; A., i, 795.64 I. M. Kolthoff, Rec. trav, chim., 1922, 41, 343; A., ii, 637.55 W. D. Treadwell and D. Chervet, Helv. Chim. Acta, 1922, 5, 633; A.,56 D. T. Ewing and E. F. Eldridge, J . Amer. Chem. SOC., 1922, 44, 1484;61 N. KanS, J . Chem. SOC. Japan, 1922, 43, 660; A., ii, 721.G8 E. Zintl and H. Wattenberg, Ber., 1922, 55, [ B ] , 3366; A,, ii, 871.I. M. Kolthoff, 2. anal. Chem., 1922, 61, 433; A., ii, 864.N. KanB, J . Chem. SOC. Japan, 1922, 43, 556; A., ii, 719.ii, 786.A., ii, 661.6 l E. R. Bishop, E. B. Kettridge, and J. H. Hildebrand, J . Amer. Chem.62 D. 0. Jones and H. R. Lee, J . Znd. Eng. Chem., 1922,14,46; A,, ii, 238.SOC., 1922, 44, 135; A., ii, 308

ISSN:0365-6217    

DOI:10.1039/AR9221900164

出版商:RSC    

年代:1922

数据来源: RSC

摘要:

PHYSIOLOGICAL CHEMISTRY.THE sad death of Benjamin Moore early in this year deprived Bio-chemistry of a brilliant and daring thinker. A pupil of Sir EdwardSharpey Schafer, he later was the first occupant of the chair of Bio-chemistry at Liverpool. While there, he and Mr. E. Whitley foundedthe Biochemical Journal, which, originally a private venture, laterbecame the official publication of the Biochemical Society. A periodof research on behalf of the Medical Research Council followed hisresignation from Liverpool, but in 1920 he returned to academiclife as first Professor of Biochemistry a t Oxford. Unfortunately,his tenure of this post was for little more than a year. His loss asa teacher and an investigator is a severe one. The ranks of Britishmen of science have been further depleted by the deaths of Dr.A. D.Waller, Professor of Physiology at London University, and theHon. H. V. Onslow. Few who have read the valuable papers onbiochemistry or genetics published from Onslow’s Cambridgelaboratory can have been aware that the whole of these carefulresearches were directed from an invalid’s couch as the result of anaccident in undergraduate days which paralysed him from the waist.Amongst our foreign colleagues, we note with regret the loss ofW. Palladin, the eminent Russian plant physiologist and biochemist,a pupil of Timiriazeff and latterly Professor a t Petrograd; ofTakamine, best known for his isolation of adrenalin; of C. A.Pekelharing, Emeritus Professor of Physiological Chemistry aCUtrecht ; and of Franz Hofmeister, the eminent investigator who formany years was Professor of Physiological Chemistry a t Strassbourg .Whilst the multiplicat8ion of new journals is generally to be de-plored, we may perhaps except the Journal of Biochemistry, editedby Prof.Kakiuchi of Tokyo Imperial University, since it is obviousthat the wide interest in biochemistry apparent in Japan should beserved by a medium for home publication. The contents are pub-lished in English, German, and French. On the other hand, theappearance of the JournaE of Metabolic Research, edited by F. M.Alien in the U.S.A., is, to our mind, less excusable. From a perusalof the papers in the numbers which have appeared there seems noadequate reason why existing periodicals should not have servedfor their publication.One fears that America is following the badexample of Germany in this math-.Of the new books, attention must be directed to “ Proteins atndthe Theory of Colloidal Behavionr,” by Jayues Loeb, which dealsin a remarkably clear manner with many problems of great import-18PHYSIOLOGICAL CHEMISTRY. 183ance to biochemists. The great interest shown on all sides in theso-called vitamins is illustrated by the recent appearance of a largenumber of volumes dealing with these substances. Apart fromthe many more or less popularly-written books, amongst whichspecial reference should be made to “ Vitamins and the Choice ofFood,” by V. G. Plimmer and R. H. A. Plimmer, several valuablereviews with extensive bibliographies have been published.“ TheVitamins,” compiled by C. Sherman and S. L. Smith, and publishedby the American Chemical Society, is especially good, whilst a secondedition of “ Die Vitamine,” by C. Funk, and an English translationof it by Dubin, are also welcome. Many new editions have alsoappeared ; “ Oxidations and Reductions in the Animal Body,” byH. D. Dakin (2nd ed.); “ Thc Determination of Hydrogen Ions,”by W. M. Clark (2nd ed.) ; “ Die Wasserstoffionenkonzentration,ihre Bedeutung fur die Riologie und die Methoden ihrer Messung,”by L. Michaelis, Part I (2nd ed., to be issued in three parts) ; “ LeuColloides,” by J. Duclaux (2nd ed.) ; and “ Physikalische Chemieder Zelle und Gewebe,” by R. Hober (5th ed., Part I). A valuablemonograph on “ Hexosamines, their Derivatives and Mucins andMucoids,” based on the author’s researches, has been published fromthe Rockefeller Institute for Medical Research by P.A. Levene.The unwieldy “ Handbuch der biologischen Arbeitsmethoden,”edited by E. Abderhalden, continues to appear, but the later numbersare not such as will dispel the feeling of disappointment and irri-tation expressed by Professor Barger in his last year’s Report. Twobiographical studies have been published which are of interest tobiochemists. “ Pasteur and his Life,” by Descour, is delightfuland will share distinction with Vallery Radot’s well-known book.On the other hand, a sense of disappointment may follow theperusal of the autobiography “ Aus meinem Lebeii ‘’ of Emil Bischer,especially if one compares it with the very good biography byJ.Kurt Hoesch which appeared in the pages of the Bericlhte.In connexion with the Pasteur Centenary, Masson et Cie are issuingan edition of the classical works of this master. The first twovolumes, “ Disymbtrie mol6culaire ” and “ Fermentjatlions etgherations dites spontanees,” are about to appear.A4miiao-acids and Proteins.”No outstanding discovery marks this year’s work in the field ofprotein chemistry, but steady progress can be reported. The diffi-* Professor Barger has asked me to mention that in referring to the workof R. Willstiitter and E. Waldschmidt Leitz (Bet-., 1921, 64, [B], 2988) inthis section of his last year’s Report he inadvertently omitted to state thatF.W. Foremen had described a similar method previously (Biochem. J.,1920, 14, 451)184 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.culties of separating the products of hydrolysis of proteins makewelcome the method described by H. W. Buston and S. B. Schryver,lwhich enables clean mixtures of amino-acids to be separated witchease from protein hydrolysates or other sources in a form convenientfor further fractionation. A protein hydrolysate, after removal oftyrosine and the diamino-acids by the usual methods, is treated withbaryta and alcohol, and carbon dioxide is passed. Several fractionsof the barium salts of the carbamates of the amino-acids, having thegeneral formula RCH<!3c>Ba, ascribed by Siegfried,2 may-be obtained.The barium prccipitates on decomposition yield clean, semi-crystalline mixtures of amino-acids.It is claimed that the methodwill effect the quantitative removal of amino-nitrogen from a solution.Another preliminary fractionation of the amino-acids which mayeventually be of considerable value is described by G. L. Foster andC. L. A. Smith,3 who apply on a laboratory scale the method ofK. Ikeda and S. Susuki in which a direct current is passed througha solution of the amino-acids, placed in a three-compartment cell.The units which are predominantly acid, such as glutamic acid,migrate to the anode, the basic substances, lysine, arginine, etc.,travel to the cathode, and the more or less neutral units remain inthe central compartment.The method appears to yield relativelylarge amounts of clean preparations of arginine and lysine.R. Engeland 5 has described a method in which the monoamino-acids are converted into the corresponding betaines as a means ofestimating certain units. From elastin he has isolated the betaineof what he believes to be a hitherto unknown amino-acid with theformula GsH2, 04N2.The general feeling that our knowledge of the sulphur-containingconstituents of the proteins is lamentably deficient is reflected inseveral papers. Of particular interest is the announcement byJ. H. Mueller of his isolation of a new amino-acid containing sulphurfrom the products of hydrolysis of commercial caseinogen withsulphuric acid. Further details of this acid will be awaited withgreat interest, but the preliminary communication states that thereare indications that it is a straight-chain compound with two arnino-groups and probably two carboxyl groups.It is uncertain in whatform the sulphur is present. W. I?. Hoffmann and F,. A. Gortner1 Biochem. J., 1921, 15, 636; A,, 1921, i, 182.2 2. physiol. Chem., 1905, 46, 401; A., 1906, i, 324.3 Pmc. Xoc. E ~ p . ~ B i o l . Med.. 1922, 19, 348.U.S. Pat. 1015891, 1912.2. physiol. Cherra., 1922, 120, 130; A., ii, 536.Proc. SOC. Exp. Biol. Med., 1922, 19, 161.J. Amer. Chem. SOC., 1922, 44, 341; A., i, 429PHYSIOLOGICAL CHEMISTRY. 185have studied the effect of acid hydrolysis on cystine and reportinteresting observations. Pure cystine, boiled for varying lengthsof time with 20 per cent.hydrochloric acid, underwent only slowdecomposition, and the authors do not think there is appreciabledecomposition of cystine during the usual protein hydrolysis. Thesmall amount of sulphur liberated was either in the form of hydrogensulphide or of free sulphur. The cystine after hydrolysis showedcertain differences from the original product in being less readilyprecipitated by phosphotungstic acid, optically inactive, moresoluble in water, and crystallising in prisms. The derivativesof the two forms of cystine showed dissimilarities. The authorsadvance the suggestion that the isomeric cystine they have isolatedis identical with the synthetic product of Erlenmeyer and Stoopand of Fischer and R a ~ k e , ~ and that “ plate ” cystine as obtainedfrom the hydrolysis of proteins has never been synthesised.The unsatisfactory nature of the existing methods for the analysisof the diamino-acid fraction of protein hydrolysates is apparent toall who have had occasion to use them.Recently J. L. Rosedale,foin an investigation of the diamino-acid content of muscle proteins,has referred to the inconsistencies of the results obtained by thewell-known method of Van Slyke.The inaccuracies associated with the estimation of the acidsin this fraction are largely bound up with those due to the methodof determining arginine, as pointed out by R. H. A. Plimmer,llwho also modified the process to render it somewhat more trust-worthy. Even when there is reason to believe that the estimationof arginine is satisfactory, the value for histidine, and thereforeindirectly that for lysine, is based on the assumption that the wholeof the non-amino-nitrogen of the fraction is represented by histidineand arginine. That this assumption is liable to lead to seriouserror is now definitely proven by the investigations of D.D. VanSlyke and A. Hiller.12 They found that the values for histidineobtained by the usual method and those based on K. K. Koesslerand M. T. Hanke’s l3 colorimetric process show agreement in thecase of caseinogen, edestin, and fibrin, but a considerable differencewith gelctiil. This led thcm to fractionate the phosphotungsticacid precipitate obtained from hydrolysed gelatin, as a result ofwhich evidence was obtained of the presence of an unidentifiedbase.Attempts to obtain the free base in a crystalline conditionBer., 1908, 41, 893; A., 1908, i, 325.Annalen, 1904, 337, 222; A., 1905, i, 119.lo Biochem. J . , 1922, 16, 27; A., i, 492.l1 Ibid., 1916, 10, 115; A., 1916, ii, 460.12 Proc. Nat. Acad. Sci., 1921, 7, 185; A., i, 63.l3 J. Biol. Chem., 1919, 39, 497; A., 1920, ii, 67186 ANNUAL REPORTS ON THE PROGRESS OF CHEBIISTRY.were unsuccessful. It is hygroscopic, decomposes slowly a t loo",and has a ratio of nitrogen to amino-nitrogen of 2 : 1. As thevalue remains constant after treatment with acids, it is concludedthat the substance is not a peptide. Further informationof thisnew basic constituent of the proteins will be awaited with greatinterest.The presence of hydroxyaspartic acid among the products ofhydrolysis of proteins once reported by Z.H. Skraup l4 has not beenconfirmed by a careful examination of the products of tryptic di-gestion of caseinogen by H. D. Dakin.15 Further study of this acidhas, however, been facilitated by his synthesis of the para- and anti-hydroxyaspartic acids from chloromalic acid and ammonia. Separ-ation of the isomerides was effected by fractional crystallisation,whilst in a later paper l6 is described the resolution of the anti-acidby: means of the strychnine and quinine salts. The para-acid wasnot resolved.Gradually, but very slowly, information on the difficult problemof the mode of linking of the amino-acids in proteins is being col-lected, but it is somewhat surprising that a comparatively simpleclass such as the protamines has not been the subject of moreextensive study from this point of view.R. E. Gross l7 has,however, isolated from the products of hydrolysis of clupeine a&peptide-like substance consisting of a t least two arginine mole-cules. He has also confirmed Nelson Gerhardt's l8 deduction thatin salmine and clupeine the monoamino-acids are linked together.Clupeine has also been investigated by H. Steudel and E. Peiser,lgwho have prepared combinations of the protamine with guanylicacid and yeast-nucleic acid in an attempt to elucidate the constitu-tion of the nucleo-proteins. E. Abderhalden 2o has succeeded inisolating at intermediate stages in the hydrolysis of silk fibroinconsiderable quantities of a d-alanyl-glycine anhydride and smallquantities of glycyl-Z-tyrosine anhydride, and of a compound con-taining serine, d-alanine, and glycine.Incidentally his examin-ation of this protein accounted for 86.4 per cent. of the total amino-acids as compared with previous figures in the neighbourhood of70 per cent. The current idea that the free amino-nitrogen ofproteins is related to the lysine content receives support from the34 Ber., 1904, 37, 1596; A., 1904, i, 538.16 J . Biol. Chem., 1921, 48, 273; a4., i, 143.16 Ibid., 1922, 50, 403; A., i, 430.17 2. phyaiol. Chem., 1922, 120, 167; A., i, 784.18 Ibid., 1919, 105, 165; A., 1919, i, 503.19 Bid., 1922, 120, 207; d., i, 784.2Q Ibid., 1922, 122, 298; d., i, 1200PHYSIOLOGICAL CHEMISTRY.187work of M. S. Dunn and H. B. Lewis,21 who have studied the distribu-tion of nitrogen in caseinogen and deaminised caseinogen. Lysinewas found to be absent from the products of the hydrolysis of thedeaminated protein and some destruction of tyrosine had alsooccurred. In a later paper,Z2 they record that the deaminatedcaseinogen can be hydrolysed by pepsin and trypsin, but a t a slowerrate than in the case of the untreated protein, whilst experimentson a dog indicate that, when tolerated, it can also be metabolisedby the organism.Protein Metabolism.At least one outstanding paper on protein metabolism has ap-peared during the twelve months under review. This is the paperby C. J. Martin and R.Robison23 on the minimum nitrogenexpenditure of man and the biological value of various proteins forhuman nutrition. Its appearance marks a very important advancein this branch of the science of nutrition. The realisation thatthe proteins do not have a uniform value in nutrition was gainingground a t the close of the last century, and was, indeed, definitelyformulated by Rubner in 1897, but t,he term " biological value "which is to-day so widely employed in this connexion was intro-duced by Karl Thomas 24 in 1909. This investigator defined the" biological value " of a protein as the number of parts of bodynitrogen replaceable by 100 parts of the nitrogen of the foodstuff,and the values he determined have been extensively employed byphysiologists.Martin and Robison began their investigationwith the modest object of redetermining the relative values forcertain cereal proteins, but they soon found great difficulty inarriving a t values which could justifiably be compared and beganto suspect that a number of the earlier investigations were open tocriticism. Accordingly, they began a careful investigation of theconditions under which valid results might be obtained, and theirpaper represents not only a sound criticism of earlier determin-ations, but also a most valuable study of the experimental methodsconcerned. They point out that Thomas adopted an experimentalmethod based on the assumption that the value of any proteinfor biological purposes remains uniform whatever the amount taken.The misleading nature of this procedure can best be appreciatedif the case of gelatin is considered.The various possibilities areexplained by the authors by means of the diagram reproduced onp. 188, in which the abscissB represent real nitrogen intake and then1 J . Biol. Chem., 1921, 49, 327; A., i, 279.l2 Ibid., 343; A., i, 292.23 Riochm. J., 1922, 16, 407.s4 Arch. Physiol., 1909, 219188 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ordinates real nitrogen output. If OM = m represent the outputof nitrogen on a nitrogen-free diet of adequate fuel value, then m isequal to the nitrogen minimum.The administration of an ideal protein (biological value 100,and utilised without waste) in gradually increasing amounts willresult in no change in the amount of excreted nitrogen, m, until theintake equals that value, a t which point, E, where H E = MO,the body will be in nitrogen equilibrium.When the intake risesabove m, the graph of intake and output will follow the line EE,,at an angle of 45" to the axis (unless the body is growing or has pre-viously been starved of nitrogen). Ordinary proteins with biologicalvalues less than 100 wilI not suffice for equilibrium to be establishedat the point E, but a t some other point El. Before nitrogenequilibrium is reached, the graph will follow the line ME,, whichmay be either straight or curved, depending on the indivisibilityof the nitrogen requirements of the body and the uniform economywith varying nitrogen intake. If these conditions are obtained,then Thomas's formula,Urine N on N-free diet + faxes N + balance ___ ___~___.__ BV = 100 N intake Ybecomes B V = 100 (1 - tan 6).In the case of a protein inadequate to supply any portion of therequirements of the organism, the graph will be the line MK parallePHX8IOLOGIOAL OHEMISTRY.189to O&; that is, the nitrogen output will always equal the nitrogenintake plus the value m. That is, BY = 100 (1 - tan 45") = 0.Whilst there mas very little reason for assuming that these graphswould prove to be straight lines, the experimental determination ofa number of points a t different levels of intake of the same proteindemonstrated that in the case of bread approximation to a straightline actually occurs. There was evidence that this may be alsotrue for milk proteins.In the case of gelatin, however, the ratiocertruiiily does not remain constant, and there is no indication thatthe amount of body nitrogen saved increases beyond that effectedby the smallest amount of gelatin administered. It can thereforebe seen that the application of Thomas's method is justifiable in thecase of bread, doubtful with milk, and of no value in the case ofgelatin. In cases where his method is not known to be trustworthy,the ratio body-N saved/food-N absorbed should be determined closeto, but below, the point of equilibrium. In any case, the biologicalvalues derived from csperiments of comparatively short durationhave a limited significance. The value of gelatin in relation to thenitrogen requirements of man is also very fully treated in an inter-esting paper by R.Robison 25; these researches have in additionserved to provide further information regarding the distributionof nitrogen in the urine on diets low in nitrogen.26Glutathione and Tissue Oxidations.Reference was made in last year's Report to the discovery byHopkins of an auto-oxidisable constituent of the cell, and furtherinformation regarding this remarkable substance has since beeneagerly awaited. Late in the year our expectations were fulfilledby the appearance of a publication by F. G. Hopkins and M. Dix0n.~7This paper is concerned with significance of glutathione in theoxidative mechanisms of the cell, but chemists will welcome thestatement that a full study of the chemical properties of this sub-stance is in progress.It should not be a task of excessive difficultyt o establish the mode of linking between the constituent amino-acids, cystine and glutamic acid, as a first step towards synthesis.The most striking fact reported in the new paper from the Cambridgelaboratory is the apparent association, in oxidative and reductiveprocesses, of the dipeptide with a tissue agency which is insolublein water and resistant to a temperature of loo", or to .treatment withalcohol. It will be recalled that 0. Meyerhof,28 in 1918, demonstrated25 Bwchem. J., 1922, 16, 111; d., i, 488.26 Ibid., 131 ; A . , i, 495.27 J. Biol. Chem., 1922, 54, 527.28 A d . Ces. PhyeiOt., 1918, 170, 428190 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.that the ability of a yeast extract or “ Kochsaft ” to give the nitro-prusside reaction showed a certain parallel with its power to restorethe “ respiration ” of washed acetone yeast.His investigationsshowed that cystine had not the latter effect, but when thioglycollicacid or thiolactic acid was added to the washed yeast in a neutralor slightly acid medium, oxygen was absorbed in an amount largert’han that required to oxidise the added acid to the disulphide form.Furthermore, Meyerhof demonstrated the even more remarkablefact that a similar action follows the addition of thioglycollic acidto a washed yeast which has been heated a t 100”.The parallel between Meyerhof’s results and those now recordedby Hopkins and Dixon is a t first sight a close one, but more detailedexamination of the experimental data indicates that further inform-ation is necessary before a definite opinion on this point can beformed.The experiments at the Cambridge laboratory onceagain demonstrate how valuable may be the information obtainedby the study of tissue activities before and after they have beenthoroughly extracted to remove water-soluble components. By thismeans assistance in recognising the co-ferment of alcoholic ferment -ation was obtained by Harden and Young, whilst more recentlyboth Meyerhof and Batelli and Stern have used this method withconsiderable success in their attempts to elucidate the nature ofthe oxidative mechanisms in the living cell. In Hopkins andDixon’s experiments.it was found that fresh muscle-tissue, afterbeing thoroughly washed, does not reduce methylene-blue, or reducesit very slowly, nor will such tissue show the absorption of oxygenand liberation of carbon dioxide which are characteristic of respir-ation. The addition of glutathione, which is, of course, one of thesoluble constituents removed by the washing, to the washed tissue,suspended in a “ buffered ” phosphate solution, will not only restorethe power to reduce methylene-blue, but also will enable the tissueto “respire.” The most interesting point is, however, that thepower to reduce the dye and to show respiration on addition ofglutathione is displayed, not only by the washed tissue, but alsoby tissue which has been extracted thoroughly with boiling wateror alcohol or which has been heated a t 100”.That the thermostable agent in the tissue residues shows a definitereducing power is demonstrated by the prompt reduction of theadded oiridised form of glutathione, enabling the system to showreduction of methylene- blue or ‘ ’ respiration.” The tissue residuesmust therefore contain a stable hydrogen donator, which is relativelyinsoluble in water, and presumably some form of stable primarycatalytic system for which glutathione is it co-agent.The thermo-stable tissue factor activated by glutathione is sensitive to oxidationPHYSIOLOGICAL CHEMISTRY. 191presumably owing to the slow oxidatioll of the relatively labilehydrogen atoms which in the normal system are so readily yieldedto other acceptors.Even the transport of the labile hydrogen toatmospheric oxygen is accelerated by glutathione, and in this casethe absorption of oxygen may be as much as 400 C.C. of oxygenper gram of dried material. This amount appears to be, from theapproximate data available, about one-tenth of the total possibleuptake of the original untreated tissue. The respiratory exchangeof this process is about unity in the early stages, but falls off after atime to nearly zero. Hopkins and Dixon’s paper contains a care-ful discussion of glutathione in relation to other systems of oxidativemechanism which are believed to exist. The molecule of glutathioneis not oxidised anaerobically by washed tissues in the presence ofmethylene-blue as T.Thunberg29 found was the case with suchsubstances as succinic acid and glutamic acid. Moreover, it doesnot suffer oxidation by atmospheric oxygen as a result of surfaceaction such as .occurred in the case of certain amino-acids in thepresence of charcoal studied by W a r b ~ r g . ~ ~ Apparently the mole-cule of the dipeptide is stable, apart from the reversible changeof the sulphur groupings which is its main characteristic. So faras the authors can ascertain, glutathione takes no part in suchoxidising agencies as are associated with the “ oxydases ” presentin the cold-water extracts of tissues. The nature of the oxidation-reduction systems existing in washed tissues still requires a good dealof elucidation, but it is quite clear that the thermolabile and unstablefactors which are probably responsible for the effects observed byThunberg (the “ oxydones ” of Batelli and Stern 31) are distinctfrom the thermostable factors described by Hopkins and Dixonand by Meyerhof.It is rather in relation to the “ respirat>orysubstance ” (Atmungskorper) and the oxidising system describedby the latter investigator that glutathione must be considered, andH. D. D a l ~ i n , ~ ~ for one, has suggested that Meyerhof’s activator torespiratory activity in killed washed yeast may be none other thanthe new dipeptide.The experiments of Meycrhof on the power of thioglycollic acidto restore the “ respiration ” of killed, washed yeast are of greatinterest in the light of Hopkins and Dixon’s observations thatwashed tissues actually have the power to effect the reductionof dithiodiglycollic acid :SZ(CH2*CO,H), -+ 2SH*CH,*C02H.2e Skand.Arch. Physiol., 1920, 40, 1 ; A., 1920, i, 784.30 Biockem. Z., 1921, 113, 257; A., 1921, i, 230.31 “ Ueber den Mechanismus der Oxydationsvorgange im Tierorganismus,”32 Physiol. Bev., 1922, 1, 394.Jena, 1914192 ANNUAL REPORTS ON THE PROQRESS OF CHEMISTRY.Dithiodiglycollic acid promotes oxygen transport less effectivelythan does oxidised glutathione in the change.If the conception of the " Atmungskorper " be such that it isregarded as representing the action of two or more substances eachrelated to some particular aspect of respiratory oxidation) thenglutathione is one of these, its activity being mainly relative torespiratory factors which are thermostable. We may perhaps quotean extract from the paper by Hopkins and Dixon : '' The factssuggest that coexisting in living tissues with the special enzymicmechanism is a thermostable mechanism for oxidations and reduc-tions.Materials in close association with structural elements areoxidised, aerobically or androbically, with the coagency of thesulphur groups of glutathione." The nature of the thermostableagent or agents residual in the washed tissues is as yet undiscovered.Mammary Secretion.A study of the origin of milk fat and its relation to the metabolismof phosphorus has been made by J. S h e e h ~ , ~ ~ who h d s that carbo-hydrate and fat can replace each other in the diet for the manufactureof fat by the mammary gland.His conclusion that the immediateprecursor is a diffusible substance of the nature of a phosphatideconstitutes further support for the work of E. B. Meigs, N. R.Blatherwick, and C. A. Carey,349 35 who showed that the increase ininorganic phosphate after the blood has passed through the mam-mary gland is sufficient to account for the whole of the milk fathaving been formed from a precursor of that type. The significanceof phosphorus in the transport of fat in the animal body is alsoemphasised by Bloor in a useful review of the subject.36The significance of colostrum remains obscure. J. H. Lewisand H. G. Wells 37 regard it as a source from which the young derivethe specific anti- bodies of the maternal organism which are believedto be associated with the globulin fraction. Support for this viewmay perhaps be derived from the experiments of T.Smith and R. B.Little,38 who found that calves are more liable to succumb to38 Biochm. J., 1921, 15, 703.34 J . Biol. Chem., 1919, 37, 1; A., 1920, i, 203.35 Ibid., 1920, 40, 469.36 Phy8iol. Rev., 1922, 2, 92.3 q J . Amer. Med. ASSOC., 1922, 78, 863.38 J. Exper. MerE., 1922, 36, 181PHYSIOLOGICAL CHEMISTRY. 193bacterial invasion when they are deprived of colostrum. Whetherthis protective action is directly due to anti-bodies or indirectly toa strengthening of the resistant powers of the organism by otherfactors is not yet clear, but it must be recalled that colostrum isricher than ordinary milk in vitamin-A, and that there is a good dealof evidence that this substance assists to maintain the defence ofthe body’s tis~ues.3~ It would now seem to be established withsome certainty that the diet of the lactating female is the chieffactor determining the concentration of vitamins in the milk, butthe paper by C .Kennedy and R. A. Dutcher 40 is important becausei t proves that the vitamin value of the milk of cows can be main-tained throughout the minter period of stall feeding by care in theselection of a ration consisting of a proper balance between grainsand leafy foods. The far-reaching influence of the diet of the motheron the nutritive value of the milk is further illustrated by the experi-ments of G. Hartwell. In a study of the effect of diet on mammarysecretion,41 she investigated the effect of changing the balance ofthe chief food components, and discovered that an excess of proteintends to cause an interference with the normal lactation leading tonutritional disturbances in the young.Further experiments 42* 43confirmed this observation, but the cause of this effect of the pro-tein has not yet been ascertained with certainty. Apparently thehigh protein diet is not in itself deleterious, a view supported bythe results of J. C. Drummond, G. P. Crowden, and E. L. G. Hill,44but it seems to demand a readjustment in the balance of certainother food units. The beneficial influence of a supplement of freshmilk or marmite (commercial yeast extract) led to suggestions beingadvanced that the vitamin-B may be the factor c0ncerned,~43 45 andfurther researches by Hartwell appear to confirm this view.46 Incontinuance of her studies on the influence of proteins on mammarysecretion, Miss Hartwell has been unable to obtain evidence thatedestin possesses any specific action as a galactogogue.47Sugar Metabolism and Diabetes.The mechanism by which dextrose is broken down in the animalbody is a subject which continues to attract widespread interest.39 Drummond, Coward, and Watson, Biochent.J., 1921, 15, 640.40 J . BioZ. Chem., 1922, 50, 339.41 Biochem. J., 1921, 15, 141.4 2 Ibid., 563.43 Ibid., 1922, 16, 78.44 J . PhysioZ., 1922, 56, 413.4 5 C. Kennedy and L. S. Palmer, J . BioZ. Chem., 1922, 54, 217.4 6 Biochem.J . , 1922, 16, 825.4 7 Lancet, 1921, i, 323.REP.-VOL. XIX. 194 AXNUAE REPORTS ON THE PROGRESS OF CHEMISTRY.There is a tendency at the moment, however, for chief attention tobe transferred from the intermediate stages, in which the hexosemolecule is degraded, to the elucidation of the changes which arebelieved to occur before the sugar molecule is actually broken.The researches of Embden and his co-workers48 have made itappear probable that phosphorus compounds are concerned in theearly stages of the metabolism of hesoses, and his conception of therble of hexosephosphoric acid in the molecule of the “ lactacidogen ’’complex presents an interesting parallel with the current viewson the significance of this acid in the fermentation of sugars byyeast.D. L. Foster and D. &I. Moyle QD have recently found thatchopped muscle not only has the power to break down addedhexosephosphate in vitro, but also has the ability to synthesisethat complex from dextrose and phosphoric acid. On all hands,evidence is accumulating that the hexose molecule, before it canbe broken down in the normal manner by living cells, must passthrough the state of hexosephosphate, and there can be little doubtthat during this process a rearrangement of the molecule occurswith the production of a highly reactive form of the sugar.The r61e of phosphates in the oxidation of hexoses in the livingcell has led A. Harden and F. R. Henley 5 O to examine the signific-ance of these salts in the oxidation of dextrose by hydrogen peroxide.W.Lob and his co-workers 51 believe that the oxidation depends onthe hydroxyl-ion concentration and that phosphates exert a specificaccelerating effect on the reaction. This view was supported byWitzemann,52 who further suggested that the specific action of thephosphates might be attributable to the necessity of the inter-mediate formation of a hexosephosphate. Harden and Henley’sinvestigations show, however, that the action of phosphates inthis oxidation is not specific, but that i t depends on their powerto regulate the reaction of the medium. Ot,her ‘‘ buffer ” systemswere equally effective. H. Elias and St. Weiss 53 have found thatintravenous injections of sodium mono- and di-phosphates maylower both alimentary and diabetic hyperglycmmia, but they donot influence the level of blood-sugar in normal subjects.It issuggested that in the former cases either the combustion of dextroseis stimulated or that storage of hexose, possibly as a phosphoricacid complex, may occur.4 0 Z. phy&ol. Chem., 1914, 93, 1, 94, 124; A., 1915, i, 344, 345, 346.49 Biochem. J., 1921, 15, 672; 8., i, 398.60 Ibid., 1922, 16, 143; A., i, 433.5 1 Bwchem. Z., 1911, 32, 43; 1912, 46, 288; 1915, 68, 368; A., 1911, ii,504; 1913, i, 123; 1915, ii, 247.52 J . Biol. Chem., 1920, 45, 1; A., 1921, i, 160.53 Weiner. Arch. inn. Med., 1922, 4, 29; A . , i, 1085PHYSIOEObICAL CHEMTSTRY. 1915SpeculationhypotheticalBornstein andas to the reactive form of sugar produced by thepreliminary rearrangement is already active.A.K. Holm 54 believe it to be lsvulose or a related sub-stance, but probably more support is to be given to the suggestionthat it is the reactive ethylene-oxide form of dextrose. J. A.Hewitt and J. Pryde 55 have already presented evidence that sol-utions of dextrose and laevulose in contact with the mucous membraneof the intestine are converted into y-glucose. Such views have ledto a re-examination of the nature of the reducing substances of theblood by E. A. Cooper and H. Walker.56 They have found thatdextrose is the chief reducing substance present, but that otherreducing substances of a more complex nature are occasionallydetectable. They obtained no evidence, however, that humanblood can transform dextrose or laevulose into the highly reactiveethylene-oxide forms, an observation which confirms the Eesults ofJ.A. Hewitt and D. H. de S ~ u z a . ~ 'More recently still, L. B. Winter and W.,Smith 5* have definitelyadvanced the opinion that the sugar present in normal bloodis an unstable form of glucose of low initial rotatory power andpossibly the so-called y-glucose or ethylene oxide form ofdextrose. This view is based on their observations that inthe protein-free filtrates of normal blood the copper-reducingvalues and those obtained by polarimetric determinations a t firstshow disagreement, but after some time, two to three days, thevalues in the latter case gradually approach the former until agree-ment is reached. In the case of diabetic bloods, however, thepolarimetric readings gave higher values than the copper method;but here again, after a period of time, agreement between the twodeterminations was obtained.It is suggested that the blood-sugar in cases of diabetes is thea- @-dextrose and that the failure of the organism to utilise sugarin this disease is due to the absence or inactivity of an enzymewhich in the normal subject converts the u- and @-sugars into theactive 7-form.Their suggestions are of very great interest and maylead to results of the highest importance, but the evidence on whichthey are advanced is far from being as convincing as might bedesired.The inability of the diabetic organism to utilise dextrose has fora long time been associated with a disturbance of the internalsecretion of the pancreas.The classical researches of von Mering64 Biochem. Z., 1922, 130, 209; A.. i, 890.66 Biochem. J., 1920, 14, 395; A., 192O,.i, 608.Ii6 Ibid., 1921, 15, 415; A., i, 698.5 7 Ibid., 667; A., i, 396.6 8 J . Phyeiol., 1922, 57, 100.H196 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.and Minkowski G9 demonstrated that a condition closely resemblinghuman diabetes mellitus may be established in dogs by completeextirpation of the pancreas.This led Lepine 6o to suggest that the condition is due tothe withdrawal of an internal secretion of the pancreas whichis essential for the utilisation of sugar. Many attempts havesince been made to demonstrate the existence of a, pancreatichormaone, chiefly by the administration of extracts prepared byvarious means from the 62, 63, 64, G5 but although occasion-ally evidence was obtained of czii improved irtilisation or of atemporary reduction of the sugar output, the results were neverconclusive.The cause of the uncertain activity of the preparationswas not definitely ascertained, but by some it was considered to bethe destructive action of trypsin. These views, together withpathological evidence that the islets of Langerhans frequentlyshow atrophy in cases of diabetes, have led two young Canadianclinicians, F. G. Banting and C. H. Best, of Toronto, to investigatethe action of extracts of the islets alone in the treatment of experi-mental diabetes in dogs. This was attained by preparing extractseither from foetal glands, in which only the islet tissue was prcsent,or from glands in which atrophy of the other parts of the structurehad been induced by ligature of the pancreatic duct.The adminis-tration sf these extracts to diabetic dogs was found to bring abouta very marked fall in the blood- and urinary- sugar and to improvethe general condition of the animals in a most striking manner.G6Encouraged by their success, they proceeded to attempt the ex-traction of the active substance frarn normal ox pancreas, usingalcohol as a means of preventing.mzyme action, a method previouslyemployed by The material thus prepared proved sopotent in the treatment of dogs: that it was tried in a severe case ofdiabetes in a boy of fourteen.The result was a reduction of theblood-sugar by 25 per cent.67To the active substance present in these extracts the discoverersgive the name " insulin.'' By mobilising a team of research workers,the Toronto investigators have in a yemarkably short time reporteda considerable progress in the study of this new substance. The69 Arclb. exp. Path. Phum., 1889, 31, 371.60 " Le diabete sucre," Paris, 1909.6 1 Starling and Knowlton, J. PhysioE., 1912, 45, 146.62 E. L. Scott, Amer. J . Physiol., 1912, 29, 3.63 J. R. Murlin and B. Kramer, J. Biol. Chem., 1913, 15, 365.6* Kleiner, ibid., 1919, 40, 153,66 J . Lab. Clin. Med., 1922, 7, 251.6 7 Xd., 260.Clarke, Johw Hopkim HOSP. Rep., 18, 229PHYSIOLOGICAL CHEMISTRY. 197method of preparation has been improved by J.B. C ~ l l i p , ~ ~ whoseprocess, now generally employed, is a prolonged and rather laboriousfractionation by means of alcohol.The administration of insulin not only reduces the hyperglycmmiain diabetes, but also that associated with sugar puncture, adrenalin,or ether anaesthesia,69 which may help to explain the observationsof L. Adler 7O that the simultaneous administration of pancreaticextract, made from hibernating hedgehogs, more or less completelysuppresses the action of adrenalin and other substances which,given alone, rouse the hibernating animal and restore its bodytemperature to summer level. Furthermore, insulin will induce acondition of hypoglycemia in normal animals. This fact is madethe basis of the provisional pharmacological standardisation ofinsulin extracts.A unit dose is described as that amount which onsubcutaneous injection will reduce the percentage of blood-sugarin a rabbit of 2 kg., which has been starved for sixteen to twenty-four hours, to 0-045 per cent.71 The latter figure is chosen becausethe fall of the blood-sugar to that level is marked in rabbits by theappearance of characteristic symptoms which take the form ofviolent convulsions and which, with intervals of coma, terminatefatally. The extraordinary fact appears established that there isa definite relationship between the amount of insulin and that ofsugar catabolised, for the symptoms of an overdose of insulin canimmediately be dispelled by the administration of an appropriatedose of sugar.This also applies to the treatment of human cases.In addition to restoring a normal blood-sugar level in diabetics,insulin tends to restore the respiratory quotient to normal figure,and also to cause the disappearance of the so-called " acetone bodies "from the urine. In experimental animals, it has also been found tore-establish the normal balance between glycogen and fat in theliver and to restore a normal glycogen content of the heart. Theclinical use of insulin is described by,Banting,!Best, Collip, Campbell,and Pletcher,72 who find that the administration of suitable dosesby subcutaneous injection twice daily removes the cardinal symptomsin a few hours, and, enabling a higher calorific intake to be consumed,leads to an increase of weight and marked improvement in themental and physical condition of the patient.Much work remainsto be done before the remedy can be widely employed, and no smallpart of its future success will probably depend on whether during68 Banting, Best, Collip, Macleod, and Noble, Truw. Roy. SOC. Canadn,1922, 16, Sec.69 Macleod, Brit. Med. J., 1922, 833.70 Arch. exp. Path. Pharm., 1921, 91, 110; A., i, 195.71 Amer. J . Phpiol., 1922, 42, 162.72 Canad. Med. Amoc. J., March, 1922198 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the period of insulin treatment the pancreas is able gradually torestore its normal function. However this may be, full creditmust be given to the Toronto investigators for a very thorough andpainstaking piece of research which has yielded results of fund-amental importance both in the clinical treatment of diabetes andin the purely scientific study of sugar consumption in the animalbody.It is a regrettable fact that already the armchair criticsare busy with attempts to belittle this fine work, and many of theletters which have appeared in the medical Press sadly remind onethat the conservatism and jealousies which opposed such advances aswere instituted by Pasteur and Lister are by no means dead.Calcium Metabolism and Vitamins.Although Professor Barger treated this subject in last year'sReport, the advances which have been made during the last twelvemonths, as well as the widespread interest in this subject, lead meto devote attention to it again this year.Whatever may be theirviews on the stiology of rickets, practically all authorities acknow-ledge the beneficial effects of treatment of this disorder with cod-liver oil. On the one hand, the supporters of theories associatingrickets with unhygienic environment or bacterial infection attributethe influence of cod-liver oil to its indirect action in increasing theresistant powers of the body ( P a t ~ n ) , ' ~ whilst those who favourthe dietetic origin of the disease tend to ascribe its effect to thepresence of an anti-rachitic vitamin. As Mellanby .showed 74 inhis experimental studies of rickets in dogs, the effect of fats in pre-venting rickets is roughly parallel to their power to promote growth,and accordingly he inclined to the view that the anti-rachitic vitaminis identical with vitamin-A.The position has, however, been considerably obscured by a massof published work on the subject which has appeared during thelast year. It would be impossible in the space a t my disposal toattempt a review of this work in its entirety, but from it three mainconclusions may be drawn. The first is the observation, nowgenerally confirmed, that sunlight or exposure to ultra-violet lightwill prevent or cure rickets in spite of the diet being defective; 75secondly, it is apparent that not only a deficiency of some factorpresent in cod-liver and other oils may induce the onset of rickets,but also that this condition may result from a disturbance of thecalcium-phosphate balance in the diet even when the hypothetical7.9 B&t.Med. J., 1922, i, 379; Glclsgow M d . J., 1922, 97, 129.74 SpeciaI Report No. 61, Medical Research Council, 1921.7& A. F. Hess and L. J. Unger, J. Amer. Med. Assoc., 1921, 7'7, 39; Amer.J. Dk. Child., 1921, 22, 186; Proc. SOC. Exper. Biol. Med., 1921, 18, 298PRYYIOLOCllCAL CHEMISTRY. 199anti-rachitic vitamin is present in what is believed to be a sufficientamount.76 Finally, McCollum and his co-workers suspect theexistence of an anti-rachitic vitamin distinct from the vitamin-A,which they regard as mainly concerned with growth.??Confirmation of the beneficial action of ultra-violet light hasbeen obtained by most workers, and a particularly interestinginvestigation which covers this point is reported in a communica-tion by H.Chick, E. L. Dalyell, M. Hume, H. M. M. Nackay, H. H.Smith, and H. Wimberger,7s who have for two years been makinga close study of deficiency diseases in Austria. With regard to thesuggestion of the existence of more than one vitamin in certain fats,one feels that the evidence submitted by McCollum tends to supportsuch a view, but that he has perhaps not yet considered the mattersufficiently from the quantitative point of view. As S. S.Zilva and I. Muira 79 showed, cod-liver oil may contain a concentr-ation of vitamin-A more than 200 times greater than that found inbutter, and to our mind some of McCollum’s results might beexplained on this basis as well as by assuming the existence of twoseparate factors.Theapparent difference in the destruction of the two factors reportedby E. V. McCollum, N. Simmonds, and J. E. Becker,slis, however,rather strong evidence in favour of two separate factors, oneof which is concerned in growth and the prevention of keratomalaciaand the other playing a r6le in calcium deposition.The whole subject of rickets is reviewed in an excellent mono-graph by V. Korenchevsky,s2 which contains a very extensivebibliography. The conclusions he has drawn from this reviewand from his own careful experimental work give general supportto the dietetic theories of the origin of the disease. For the preven-tion of rickets the following factors may, in his opinion, be taken asmost important : adequate amounts in the mother’s diet of anti-rachitic factor ( ? vitamin-A), calcium, and phosphates during preg-nancy, and especially during lactation ; a similar diet for the infant,and abundant light, fresh air, and exercise.Similar conclusionsare also drawn from another quarter by H. C. Mann, who has justpublished the results of a careful clinical investigation into the76 E. V. McCollum, N. Simmonds, P. G. Shipley, and E. A. Park, J . BioZ.Chem., 1921, 47, 507; d., 1921, i, 757.7 7 E. V. McCollum, N. Simmonds, J. E. Becker, and P. G. Shipley, BUZZ.John Hopkins Hosp., 1922,33,229; Shipley, Park, McCollum, and Simmonds,Arner. J . Hyg., 1921, 1, 512; Arner. J . Dis. Child., 1922, 23, 91.This has been also pointed out by Zilva.807@ Lancet, 1922, ii, 7.lS Ibid., 1921, i, 323.80 Ibid., 1922, i, 1244.81 J.Biol. Chem., 1922, 53, 292.82 Special Report No. 71, Medical Research Council, 1922200 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.relative importance of environment and diet as factors in thecausation of rickets in London children.83 In view of the discoveryof the action of light in preventing and curing rickets, it would appearthat convergence of opinion between the two extreme schools ofthought will shortly take place. In any case, modern researchesleave no excuse for the continuation of the destructive effects ofthis terrible disease. As has been stated above, there is alreadygeneral agreement on the beneficial effects of the administrationof cod-liver oil in rickets, so that considerable interest attachesto the efforts to isolate the active substance it contains.The oldertheories attributed the almost specific action of cod-liver oil tovarious causes. By some it was held that the minute trace of iodinefound in the oil is the active constituent, whilst others believed thetherapeutic palue to be dependent on the small amounts of nitrogenbases frequently present. A third theory which held ground for a longtime regarded the peculiar nature of the unsaturated fatty acids asbeing responsible for the ease with which the oil can be absorbed andutilised by an ill-nourished system. All these theories are now unten-able, since it has been shown that the active substance can betransferred almost without loss to the unsaponifiable fraction ofthe oil, if precautions are taken to prevent 0xidation.~49 85, Thisfraction contains no detectable trace of nitrogen or iodine and isof course entirely free from fatty a~ids.~7That the anti-rachit'ic vitamin and vitamin-A are probably ofthe same type, if McCollum should be correct in thinking that theyare not the same substance, is indicated by the observations ofT.F. Zucker, A. M. Pappenheimer, and 31. Barnett 88 and of T. 3'.Zucker and M. B. Gutman.89 Attempts to fractionate the unsaponi-fiable material from cod-liver oil by J. C. Drummond and K. H.Coward have as yet yielded no positive information regarding thenature of the vitamin.87 The origin of the vitamin in cod-liver oiland other fish oils has been studied by J.C. Drummond and S. S.Zil~a,~o who drew the conclusion that the primary source is repre-sented by the marine plant life, chiefly unicellular. The actualsynthesis of the vitamin by a typical marine diatom, Nitsxchinclosterium, growing in pure culture in an inorganic medium, wasdemonstrated by H. L. Jameson, J. C. Drummond, and K. H.whilst the presence of the growth-promoting factor inSpecial Report No. 68, Medical Research Council, 1922.~ 4 * McCollum and M. Davis, J . Biol. Chem., 1914, 19, 245.65 Steenbock and Boutwell, ibid., 1920, 42, 131.88 K. H. Coward and J. C. Drummond, Biochem. J . , 1921, 15, 530.87 J. C. Drummond and K. H. Coward, J. SOC. Chem. Ind., 1922,41,561 R.1313 Proc. SOC. Exp. Biol. Med., 1922, J.9, 167. 89 Ibid., 169.Biochem.J., 1922, 16, 518. 9 1 Ibid., 482PHYSIOLOGICAL CHEMISTRY. 201such organisms has also been recorded by J. H j ~ r t . ~ ~ An exhaustivestudy of the modern methods of the preparation of cod-liver oilsatisfied J. C . Drummond and S. S. Zilva that little appreciable lossof vitamin-A occurs, unless attempts are made to bleach oils ofinferior quality by methods involving oxidation.93 These sub-jects are also arousing considerable interest in agricultural circles.E. B. Hart, J. G. Halpin, and H. Steenbock 94 have examined thecauses of weakness of the legs in chicken and conclude from theirinvestigations that a factor of primary importance in avoiding thistrouble is an adequate supply of the vitamins present in cod-liveroil. R. H. A.Plimmer and J. L. RosedaleYg5 while agreeing that theadministration of cod-liver oil is of great value to chicken that arebeing reared on the intensive system, are inclined to attribute thecharacteristic tendency to weakness of the legs in such birds toan insufficient supply of vitamin-B.The assimilation of calcium by milking cows has been carefullystudied by a group of investigators a t the University of Wisconsin,and their results have considerable practical importance. E. B.Hart, H. Steenbock, C. A. Hoppert, and G. C. Humphreyg6 havefound it possible to maintain milking cows in calcium and phos-phorus equilibrium when on a ration of alfalfa (lucerne) hay andcereal products, provided that the hay had been cured in a mannerwhich prevented undue exposure to air or sunlight.When thehay had not been prepared with these precaution^,^^ negativecalcium balances tended to prevail. The difference in the effectof the two types of hay is attributed to a difference in the degreeof destruction of a vitamin which assists calcium assimilation duringthe curing process. On green alfalfa, calcium retention was moremarked than when the hays were used.98Lipoids.The researches of Levene and his colleagues on lecithins continueto clear up various points concerning the structure of these sub-stances. P. A. Levene and T. Ingvald~en,~~ and P. A. Levene andH. S. Simms 1 have shown by their studies of liver lecithins thatseveral, possibly four, such compounds exist. Later investigationsB2 Proc. Roy. SOC., 1922, [B], 93, 440.93 J . SOC. Chem. Ind., 1922, 41, 2 8 0 ~ .94 J . Biol. Chem., 1922, 52, 379.O 5 Biochem. J., 1922, 16, 11.96 J . Biol. Chem., 1922, 63, 21.O 7 Ibid., 1922, 54, 75.st? Ibid., 1922, 53, 21.9s Ibid., 1920, 43, 359; A., 1920, i, '788.1 Ibid., 1921, 48, 185; A . , 1921, i, 842.H 202 ANNUAL REPORTS ON THE PROGRESS O F CHEMISTRY.have been concerned with the nature of the fatty acids present in egg-lecithin,2 brain-lecithin,3 and kephalin.4 Comparing the mixedlecithins of liver and those of the egg-yolk, the main difference isseen to lie in the much larger proportion of highly unsaturatedfatty acids present in the former substances. The possibility has notyet been adequately considered that the variety of lecithins and thehighly unsaturated nature of the fatty acids they contain are dueto the part which lecithin probably takes in the transport and inter-mediate metabolism of fats. Brain lecithin and kephalin werefound to contain oleic acid as well as acids in which more thanone double bond is present. Of the latter acids, arachidonic acidwas detected in the form of its octabromo-derivative or by reductionto arachidic acid. Resolution of Linnert’s “ sahidin ” into severalfractions, of which one was lecithin, by S. Friinkel and A. Kassghas further simplified the list of lipoids, but in another paper thesame authors have made up for the loss by describing a new phos-phosulphatide from brain.?The substance “ tethelin,” isolated from the anterior lobe of thepituitary gland, by T. B. Robertson,s and believed by him to be thegrowth-promoting principle of that tissue, has been examined byJ. C. Drummond and R. K. Ca~man,~ who conclude that the productis an impure mixture of lipoid substances. They were also unableto confirm that tethelin, or indeed the anterior lobe of the pituitarygland itself, has any effect on the growth of mice when administeredby the mouth.J. C. DRUMMOND.P. A. Levene and I. P. Rolf, J. Biol. Chem., 1922, 51, 507; A., i, 621.Idem, ibid., 1922, 54, 99; A , , 1923, i, 11.4 Idem, ibid., 91 ; A., 1923, i, 11.Biochern. Z., 1910, 24, 268.Ibid., 1921, 124, 216.J. Bid. Chem., 1916, 24, 397; A., 1916, i, 350.Biochem. J., 1922, 16, 53; A., i, 491.7 Ibid., 206

ISSN:0365-6217    

DOI:10.1039/AR9221900182

出版商:RSC    

年代:1922

数据来源: RSC

摘要:

AGRICULTURAL CHEMISTRY AND VEGETABLEPHYSIOLOGY.WITH one or two possible exceptions, the year 1922 has not beenmarked by any really outstanding discoveries in the domain ofagricultural and plant chemistry. There has, however, beensteady progress along the lines already developed; the results ofthe work of recent years are being sorted out and viewed in properperspective ; many conflicting views and conlradictory findingsare being reconciled by the increasing realisation of the complexityof the problems involved; thus the ground is being cleared and,one hopes, suitable jumping-off places are being made in preparationfor further advances into the unknown country beyond the presentfrontiers of our knowledge.In the present Report the results which have been publishedin the past year will be utilised in an attempt to indicate the relationsof the various parts of this branch of chemistry to one another.This can be done most easily and logically by taking the livingplant as the point about which all our problems centre, and con-sidering these problems mainly in their bearings on the plant.Thenormal development of the living plant depends on an adequatesupply of the raw materials from which it builds up its tissues,and on the maintenance of conditions favourable to the processeswhereby it effects that synthesis. Of these raw materials all savecarbon dioxide, and in certain cases nitrogen, are supplied by thesoil, which is therefore considered first under the proposed methodof treatment of the subject. The conditions obtaining in the soilare then considered in their relation to the growth of the plant,after which the processes whereby the plant constituents are builtup from the raw materials obtained from the soil and from the airare discussed.The chemistry of plant products calls for noticein this Report only in its bearings on the mechanism of the vitalprocesses of the plant and on the characterisation of differentspecies by their constituents. The chemistry of the vegetablemicro-organisms forms a distinct branch of the subject, except asregards the micro-organisms of the soil, and is dealt with, so far asspace allows, in a separate final section of this Report.Fertilisers, and the more technical aspects of soil work, includingsoil analysis, are only dealt with incidentally in this Report.These203 H* 204 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.aspects of the subject are discussed in the Report to the Societyof Chemical Industry on “ Soils and Fertilisers.”T h e S o i l .From the point of view of plant nutrition, the most importantof the constituents of the soil system is the liquid phase, the so-called“soil solution,” the medium from which the roots absorb moistureand nutrient substances. The concentration and composition ofthis solution are dependent, on the one hand, on the moisturerelationships of the soil, and on the other on the nature of themineral and organic soil constituents, which are subject to attackby purely chemical and by biological agencies.According tomodern conceptions, the particles constituting the mineral frame-work of the soil are coated with a colloidal layer composed in partof the products of wmthering of minerals, and in part of the degrad-ation products of organic residues. This colloidal layer exerts aprofound influence on the physical, chemical, and biologicalproperties of the soil.The Soil Colloids.?‘he organic colloidal matter of the soil is conveniently describedas humic matter, although the terms ‘‘ humus ” and ‘‘ humic acid ”now have a more precise significance to the soil chemist: theformer term refers to that part of the soil organic matter that issoluble in alkali and precipitated by acids, whilst “ humic acid,”strictly speaking, consists of that part of the humus that is insolublein alcohol.There is considerable controversy in Germany as to the mode oforigin and the chemical nature of humic acid, although the questionthere a t issue is the relation of this material to coal formation.Eller and Marcusson have advanced rival theories according towhich humic acid is derived from phenolic substances and fromfuran derivatives, respectively.Marcusson 2 maintains that thehumic acids obtained from brown coal contain condensed furanand benzene rings, and that they stand in close relationship to, ifthey are not identical with, the synthetic acids prepared fromsugars. He is supported by Jonas in asserting that Eller’sproducts do not resemble the naturally occurring humic acids, butEller maintains his position.Schrader has studied the productionof humic acid from lignin by alkaline ~xidation.~ The uncertaintyof the whole position is really due to the lack of characterisation of* Ann. Reports, 1921,18, 194.J. Marcusson, 2. angew. Chem., 1922, 35, 165; A., i, 436.K. J. Jonas, Brenneto# Chem., 1922, 3, 52; A., i, 326.W. Eller, ibid., 49, 55; A., i, 326.H. Schrader, ibid., ii, 161; A.! i, 637AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 305humic acid. The grounds on which the various artificial productsare stated t o be identical with the natural material are usuallyfar from convincing.on the humic acid of peat is needed; the problem is at presentbeing studied on these lines in the Rothamsted laboratories. Theso-called “ ulmin ” which forms a principal constituent of dopplerife,a gelatinous deposit found in peat bogs, is probably closely relatedin nature and in mode of formation to the humic acid of the soil.A suggestive investigation of this material has been carried out inthis country.Whatever may be the mechanism of humification, the resultingproduct is of great importance in the soil.Its action, which con-sists partly in modifying the moisture relationships and otherphysical properties of the soil, has been discussed by the reporter.*The inorganic colloidaE mutter of the soil, variously known as the“ clay ” (in this country), the “ ultraclay ” (in the United States),or the “ colloidal clay’’ (in Germany), consists of the very finemineral particles of the soil, and of the products of weathering ofthe soil minerals.From the fact that the smallest clay particlethat could be observed by microscopic methods had a diameter ofabout 0.0001 mm., Whitney9 has advanced a hypothesis in whichthe non-observance of particles smaller than this is assumed to bedue to the fact that particles of this size contain so few moleculesthat they are disintegrated by the bombardment of water molecules,leaving the oxides of silicon, aluminium, and iron in colloidal form.It must, however, be pointed out that particles of diameter lessthan 0.0001 mm. are beyond the resolving power of the microscope,so that their non-observance is no evidence that they do not exist.Gordon lo disagrees with Whitney’s theory, and prefers to regardthe process as based on chemical reactions of hydrolysis, etc.Tothe writer, this discussion seems to be rather beside the mark; ifthe nature of the products of weathering of soil minerals, and theeffect of conditions on the process, can be elucidated, it matterslittle whether they are produced by bombardment with wafermolecules, or by hydrolysis, if indeed these do not both meanpractically the same thing.The effect, on the decomposition of minerals, of micro-organismssuch as diatoms l1 or bacteria l2 has been investigated.For example, S. OdBn, Trans. Faraday SOC., 1922,17, 288.F. V. Tideswell and R. V. Wheeler, T., 1922,121, 2345.a H. J. Page, Trans. Faraduy Soc., 1922, 17, 272.M. Whitney, Science, 1921, 54, 653; A., i, 708.lo N.E. Gordon, i b i d . , 1922, 65, 676; A., i, 1227.11 W. J. Vernadsky, Compt. rend.,.1922, 175, 451); A , , i, 1096,l2 D. Wright, Calif. Univ. Pubs. Agric. Sci., 1922, 4, 245.Further work on the lines of that of Od6206 ANNUAL REPORTS ON TEE PROGRESS OF CHEMISTRY.It has been shown 13 that the values of such physical constantsof a soil as density, pore space, water-absorbing power, swellingon moistening, are directly related to the amount of clay or organicmatter in the soil.The jlocculation of soils, which has such an important bearingon the moisture relationships, and on tilth, is of course a functionof the colloidal matter in the soil. Comber’s hypothesis withreference to the flocculation of soils by lime l4 has beendeveloped and strengthened by further work 15; it seemsreasonably certain that the “ abnormal ” flocculation of clayby calcium salts in the presence of alkali is due to the emulsoidsiliceous gel coating around the particles, which masks to agreater or less degree the suspensoid properties of the mineralcore. The same hypothesis has been used to explain the differ-ence between what are known in the ceramic industry as “ fat ’’and “lean” clays.ls A comprehensive study of the floccu-lation of clay and peat by calcium salts in alkaline solution hasalso been carried out by Mattson.17 Clay suspensions, if leftundisturbed, frequently show a curious layer formation.Thisphenomenon has been investigated,lB and it is stated that in anyone layer the particles are of uniform size, and that the spacebetween the layers contains particles uniformly dispersed.Fromthe rate of rise or fall of the layers the size of the particles may becalculated by means of Stokes’s law. Clays of different originsnd different reaction have been found to have the same isoelectricpoint.19 Flocculation has been used as the basis of a method forthe determination of colloidal clay in soils Zo and it is claimed thatthe method is more trustworthy than that based on hygroscopicitymeasurements.Absorption and basic exchange, between the soil colloids and theconstituents of the soil solution, have an important bearing on thecomposition and concentration of the latter. Many of the short-comings of present methods of soil analysis may be ascribed to alack of sufficient discrimination between that part of the bases ofthe soil which is absorbed, and therefore capable of liberation bybasic exchange, and that part which is actually insoluble, butl3 B.A. Keen and H. Raczkowski, J. Agric. Sci., 1921, 11, 441.l4 Ann. Reports, 1920, 17, 186.l6 N. M. Comber, J . Agri. Sci., 1921, 11, 450; A., i, 212; ibid., 1922,18 N. M. Comber, J. SOC. Chem. Ind., 1922, 41, 7711.1 7 S. E. Mattson, Koll. Chem. Beihefte, 1922, 14, 227; A,, i, 800.1* E. Ungerer, ibid., 1921, 14, 63; A,, ii, 06.Is 0. Arrhenius, J . Amer. CAem. SOC., 1922, 44, 621 ; A., i, 707.20 R. Sokol, Internat. Mitt. Bodenkunde, 1921, 11, 184.12, 372; see also Trans. Paraday Soc., 1922,17, 349AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 207capable of solution by acids.Hissink 21 has carried out a suggestiveinvestigation on this point, which merits detailed perusal. Thepresent state of our knowledge of absorption and basic exchange insoils has been reviewed by Fisher and by von nos tit^,^^ who hasdemonstrated how the whole of the readily available potash in asoil may be removed by basic exchange with ammonium nitrate,followed by leaching, so that plants grown on soil so treated showall the symptoms of potash-starvation. The influence of soilcolloids and of hydrogen-ion concentration on the availability ofcalcium, potassium, and phosphates 24 and of ammonium salts 25has also been investigated.Biochemical Changes in the Soil.The composition of the soil solution is influenced not only bythe chemical processes of weathering and the like, and by physico-chemical phenomena such as absorption and basic exchange, butalso to an even greater extent by the biochemical processes broughtabout by the plentiful and varied soil microflora and microfauna.The nitrogen cycle-the complex series of reactions throughwhich the nitrogen compounds of the soil pass-is perhaps of thegreatest importance in this connexion.Nitrogen is added to thesoil in the form of artificial fertilisers and of plant and animalresidues, and by means of biological fixation, whilst it may belost by leaching, by evolution of gaseous nitrogen, and by absorp-tion by the growing crop. The level a t which the nitrogen contentof any soil stands depends on the interaction of these factors, whichare variously affected by different conditions.26Nitrogen fixation by free-living bacteria in the soil is a factoras to the quantitative importance of which under field conditionsthere is still some uncertainty.The influence of salts on theprocess has been investigated 27 ; it was found that nitrogen-fixingbacteria were much more resistant to the toxic action of salts thanare ammonifiers and nitrifiers, and that many common soil saltshad a stimulating action. Boric acid causes increased fixation byAxotobacter chroococcum in the presence of humus, although its41 D. J. Hissink, Internat. Mitt. Bodenkunde, 1922, 12, 81.22 E. A. Fisher, Trans. Paraday SOC., 1922,17, 305.23 A. von Nostitz, Mitt.deut. landw. CTes., 1921, 36, 608; A., i, 511; J.24 N. E. Gordon and E. B. Starkey, Soil Sci., 1922,14, 1 ; A., i, 1104.25 B. Aarnio, 2. Pflanz. Diing., 1922, [A], 1, 320; A., i, 1227.2 6 For a discussion of this problem see F. E. Bear, J . Amer. Soc. Agron.,27 J. E. Greaves, E. G. Carter, and Y . Lund, Soil Sci,, 1922, 13, 481; A.Landw., 1922, 70, 46.1922, 14, 136.i, 976308 ANNUAL REPORTS ON THE PROGRESS O F CHENTSTRY.action in absence of the latter is inappreciable. The same is trueof its toxic effect in higher concentrations.28 A new nitrogen-fixingbacillus has been described.29 The functions of the unicellulargreen alga which are present in most soils are not yet known,According to Wanr1,~0 they can assimilate atmospheric nitrogen ;this result, if confirmed, might be of considerable importance inrelation to the nitrogen economy of the soil; according to work(as yet unpublished) in the Rothamsted laboratories, however,the question cannot yet be taken as settled.A moment’s reflection will show that in the process of ammoni-fication, whereby the nitrogen of the complex organic material ofplant residues and the like is rendered soluble by the action ofsoil micro-organisms, the initial stages of the action of theseorganisms must depend largely and probably exclusively on extra-cellular enzymes, since the complex materials are all insoluble orcolloidal, and therefore presumably cannot be absorbed as suchinto those micro-organisms which feed “ osmotically.” Several ofthe bacteria which are most commonly found in the soil have beenshown 31 to produce extracellular proteases which were activewithin a range of hydrogen-ion concentration of pH 4-9, with anoptimum zone of 6 to 7, a zone closely corresponding with theaverage hydrogen-ion concentration of a fertile soil.Moulds mayalso be active ammonifying agents; the production of ammoniafrom protein by the action of AspergiZZus niger has been investi-gated.32 The biological degradation of organic nitrogen compoundsin humus forest soils has also been investigated.=Nitrification-the final stage in the chain of reactions wherebyorganic nitrogen in the soil is rendered available to the plant-is a process requiring an ample supply of air. The physical con-dition of the soil thus has a direct effect on nitrate formation;this aspect of the subject has received further study.34 The kineticsof nitrification have also been investigated; 35 the reaction as itwhole is found to be an autocatalytic unimolecular reaction, increasein nitric acid being in accordance with the equation :log x - log(A - X) = K(t - t‘).The proportions of the total nitrogen of a soil which are present2 8 J. Voicu, Compt.rend., 1922, 175, 317.2s G. Truffaut and N. Bezssonoff, ibid., 544.30 F. B. Wann, Amer. J . Bot., 1922, 8, 1.31 K. G. Dernby, Biochem. Z., 1921,126, 105; A., i, 405.32 V. S. Butkevitsch, ibid., 1922, 129, 445; A., i, 707; see also A., i, 973.33 H. Suchting, Z. Pflanz. Diing., 1922, 1, 113.34 P. H. Carpenter and A.K. Bose, Ind. Tea Assoc., Sc. Dept. Quart. J.,1921, 103; see also T. L. Lyon, J. Amer. SOC. Agron., 1922, 14, 97.35 K Miyake and S. Soma, J. Riochem. (Japan), 1922,1, 123; A., i, 1096AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 209at any time in the form of soluble nitrate and of insoluble organiccompounds depend on the interaction of the various groups ofmicro-organisms, and on their conditions. Thus it is known thatin the presence of an abundance of a non-nitrogenous source ofenergy, such as carbohydrate? much of the soluble nitrogen in thesoil is reassimilated by the soil organisms and thus locked up for atime in a form in which it is not available to the plant. The effectof a straw mulch in depressing the nitrate content of the soil hasbeen inve~tigated.~C This depression is greatest when the soil isat its wettest after rain; and it seems probable that this result isto be explained by the washing down into the soil of soluble decom-position products of the straw, which would then exert the actionabove menti~ned.~’The sulphur cycle has received a considerable amount of attentionof recent years.The reduction of sulphat,es to sulphides underanaerobic conditions, such as obtain in deep subsoils, has beenfound to occur in depths from 10 metres to 34.5 metres in theAmsterdam distri~t.~* The organism operative in this process isMicrospira desulphuricans. Sulphides are similarly found in thelower layers of peat soils.39 Under azrobic conditions, on theother hand, sulphate formation occurs.Demolon 40 has studiedthe sulphur-oxidising power of soils and concludes that theammonifying organisms are apparently responsible, and that theproperty is not bacteriologically specific. Sulphur-oxidation has,however, received most attention a t the New Jersey ExperimentStation, by J. G. Lipman and his co-workers. Two specificorganisms, Thiobacillus thio-oxydans and Thiobacillus B., have beenisolated; 41 the former, which acts best in acid media, is not com-monly found in cultivated soils, except after treatment with sulphur ;the latter, which acts in alkaline solution, appears to be closelyrelated to Beijerinck’s Thiobacillus thioparus, and is commonlypresent in cultivated soils in America, especially “ black alkali ”soils.Thiobacillus thio-oxydans is an extraordinary organism ; itsoptimum growth occurs a t a hydrogen-ion concentration ofpH 2.8-2.0, and it can exist in a medium of p , 0.68.42 It is auto-36 W. A. Albrecht, Soil Sci., 1922, 14, 299.37 See also J. A. Bizzell, J. Amer. SOC. Agron., 1922, 14, 320.38 C. A. H. von Wolzogen Kuhr, Proc. K. Acad. Wetensch. Amsterdam,1922, 25, 188; A., i, 1228.39 C. 0. Rost, Soil Sci., 1922, 14, 167.40 A. Demolon, Compt. rend., 1921, 173, 1408; A., i, 312.41 S. A. Waksman, J . Bact., 1922, 7, 231, 605, 609; Soil Sci., 1922, 13,329; &4., i, 706; S. A. Waksman and J. 8. Joffe, J . Bact., 1922, 7, 239; J. S.Joffe, Soil Sci., 1922, 13, 161.42 J. G. Lipman, S. A. Waksman, and J. S. Joffe, SoiE Sci., 1921, 12, 475;A , , i, 303210 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.trophic, utilising sulphur as a source of energy, and assimilatingcarbon dioxide.It has also been found that certain bacteria canoxidise zinc blende to zinc sulphate.43 Lantzsch concludes, froman investigation into the various phases of the sulphur cycle, that" the sulphur cycle in soil does not justify the assumption that freesulphuric acid is produced (directly or via hydrogen sulphide)and exerts a solvent action. An increase of soil acidity is obtainedonly with heavy dressings of sulphur." The bearings of sulphur-oxidation on the soil reaction and on crop production are discussedlater in this Report.Lantzsch 45 also suggests the possibility of a direct connexionbetween nitrification and the solubility of the phosphates of thesoil, inasmuch as it is stated that the seasonal maxima of nitratecontent of the soil coincide with maxima for the phosphate contentof the soil solution.Soil Moisture and the Soil Solution.The moisture relationships of the soil, which are so dependenton the amount of colloidal matter present, themselves have a directbearing on the strength of the soil solution, inasmuch as the extentto which the latter may be subject to dilution or concentrationvaries with the moisture-holding capacity of, and rate of evaporationof water from, the soil.It has been found that the absorption ofwater by the colloidal matter extracted from a number of widelydifferent American soils was relatively constant.46 Oddn haspublished a suggestive note on the hygroscopicity of Therate of evaporation of water from a soil receiving farmyard manureevery year, and therefore relatively rich in colloidal organic matter,is less than that from unmanured soil or from soil receiving onlyartificial fertiliser~.~~ The evaporation of water from soil in thefield has been investigated by Helbig and ROs~ler.~D Evaporationof water from the soil tends to cause an accumulation of solublesalts in the surface layers of the soil.This takes place, as wouldbe expected, during the summer months, especially in a dry summer,and is most pronounced in the top quarter of an inch of theIn this investigation the concentration of soluble salts was deter-43 A. Helbronner and W.Rudolfs, Cornpt. rend., 1922, 174, 1378; A.,i, 706.44 I(. Lantzsch, Internat. Mitt. Bodenkunde, 1922, 12, 22.45 K. Lantzsch, Zoc. cit.46 W. 0. Robinson, J . Physical Chem., 1922,26, 647; A., i, 1228; see alsoR. 0. E. Davis, J . Amer. SOC. Agron., 1922, 14, 293.41 S. Odh, Trans. Baraday Soc., 1922,17, 244.48 B. A. Keen, J . Agm'c. Sci., 1921, 11, 433.49 M. Helbig and 0. Rossler, 2. Pflanz. Dung., 1922, 1, 95.60 C. E. Millar, Soil Sci., 1972, 13, 433AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 21 1mined by the freezing-point method, which has been extensivelystudied by Bouyoucos. This worker concluded 51 from freezing-point and dilatometer measurements that a portion of the soilmoistlire was “unfree,” and inactive as a solvent.Parker nowpresents evidence 52 that BOU~OUCOS’S assumptions are not wellfounded, and that soils do not contain a considerable percentageof water which does not act as a solvent. Although the old classi-fication of soil moisture into hygroscopic, capillary, and gravitationalwater has certain objections, it seems to be the best yet offered,Keen 53 has published a useful general discussion of modern viewson the moisture relationships of the soil.As an alternative to the examination of the soil solution in situ,several methods have been devised for isolating it from the soil.These methods fall into several categories, one of which is theapplication of very high pressures to the moist soil. This methodwas used in California by C. B. Lipman, and it has now beendevelaped in the same laboratory by Burgess,54 who by the applic-ation of pressures up to 16,000 lb. per square inch has succeeded inexpressing from soils a t a moisture content of 50 per cent.of theirmoisture-holding capacity, between 45 and 60 per cent. of theirtotal moisture. By an examination of the composition of the liquidso expressed, and comparison with a 1 : 5 water extract, it is con-cluded that the liquid obtained by the direct pressure method doesrepresent the true soil solution, and further, that the balance ofevidence is against the existence of “unfree” water, thus con-firming Parker’s concl~sions.~~In the reporter’s opinion, there is still some reason to doubtwhether any of the methods for isolating the soil solution arereally capable of doing so, a t any rate for heavy soils, in whichthe amount of colloidal matter is high.These methods are usuallymost successful with coarse soils, in which it is not difficult tosuppose that a large part of the soil solution may be regarded asexisting as a free water film on the surface of the comparativelybare mineral grains. For heavy soils much greater difficulties areencountered, as noticed by Burgess 56 with the Parker displacementmethod, and this is confirmed by experience of the same methodin the Rothamsted laboratories. In such soils it must be supposedthat the soil solution is to a large extent imbibed in the capillarychannels of the compound particles, and in the hydrophilous gel61 Ann. Reports, 1921, 18, 200.52 F.W. Parker, Soil Sci., 1922, 13, 43; A , , i, 116.63 B. A. Keen, Trans. Paraday Soc., 1922, 17, 228.see also W. L. Power, Soil Sci., 1922, 14, 159.64 P. S. Burgess, Soil Sci., 1922, 14, 191.5 5 F. W. Parker, Zoc. cit.For “ Wilting point *’b6 P. S. Burgess, Zoc. cit212 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.coating of the particles ; it will therefore be more difficult to removethan that in a coarse soil containing little colloidal matter, and ina displacement method the possibility of dilution by the displacingliquid will be considerable. The degree of hydration of the gelcoating on the particle is doubtless much grkater on the outsidethan towards the surface of the mineral “ core.” If this is so, itfollows that by any method in which an attempt is made to removethe soil solution from the soil, a part of this solution will be removedwith greater ease than the rest; if at the same time it is assumed-and there appears to be some grounds for the assumption-thatthere is a concentration gradient in the soil solution as betweenthe outside and the inner layers of the gel coating of the particles,then i t would follow that the first portions of the expressed soilsolution would have a different concentration from that of theportions removed later.This is not found for relatively coarsesoils, but there is some indication of it in Burgess’s results 56 forsoils containing a fair amount of clay. The concentration of thetrue soil solution could then only be expressed as a mean value,represented possibly by that of a portion of the solution collectedwhen about half of the original soil moisture had been isolatedfrom the soil.The reaction of the soil solution continues to provoke a biggervolume of work than practically any other soil problem.Muchconfusion has resulted in this field from the fact that “ soil acidity ”is a complex phenomenon, in the development of which severaldistinct factors are involved; these have not always been clearlydistinguished, Lemmerman and Fresenius 57 emphasise this point,and distinguish three types of soil acidity : (1) actual acidity ofthe soil solution, due to the presence of acids; (2) latent acidity,developed in the presence of neutral salts, owing to the liberation,by basic exchange, of readily hydrolysed iron and aluminium salts ;(3) latent acidity, developed in the presence of salts of weak acidswith strong bases, the base being absorbed by the soil colloids andthe acid left.The measurement of the hydrogen-ion concentrationof the soil solution 58 does not necessarily give any indication ofthe amount of base required to bring about neutrality; this isdetermined partly by the buffer action of some of the soil con-stituents,59 and partly by the fact that some of the base is precipit-86 P . S . Burgess, lot. cit.5 7 0. Lemmermann and L. Fresenius, 2. Pflunz. Diing., 1922, [ A ] , 1, 12;68 See, for example, D. J. Healy and P. E. Kanaker, SoiE Xci., 1922, 13,59 E. A. Fisher, Nutwe, 1921, 108, 306; A., i, 510; H.W. Johnson, SoilA., i, 510.323 ; A., i, 519.S c i . , 1922, 13, 7 ; A . , i, 708AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 213ated or absorbed by the soil colloids. Calcium hydroxide andbicarbonate are involved in this latter effect to different extents;this helps to explain the different ‘‘ lime-requirement ” valuesgiven by the use of these two reagents.60 The titration curveobtained by measuring the rate of change of hydrogen-ion con-centration on the gradual addition of acids and alkalis gives valuableinformation as to the magnitude of the buffer effects in a soil,which will determine to what extent the latent acidity of the typesspecified under (2) and (3) above can produce harmful effects inthe soil.61 A well-buffered soil is more productive than a badlybuffered one; clay soils are better buffered than sandy soils.62The relation of the soluble iron or aluminium of the soil to soilacidity forms the basis of Comber’s qualitative test,63 now describedin a modified form; 64 a “ lime-requirement ” method based onthis test has been de~cribed.~~ It is usually supposed that aciditymay be caused by the presence of aluminium salts owing to theirready hydrolysis.It is now suggested, however, that the presenceof soluble aluminium salts in soils is the result rather than thecause of soil acidity.a6 It seems likely that the first explanationmay be correct in some cases, as in case (2) above, and the secondin other cases, as, for instance, when mineral acid is, produced inthe soil by the use of “ physiologically acid ” fertilisers like sulphateof ammonia, or by the oxidation of sulphur.Crowther 67 haspublished a review of the physico-chemical aspects of soilacidity.The use of the bacterial oxidation of sulphur as a means ofincreasing the hydrogen-ion concentration of the soil continues toattract much attention in America. Potato scab disease can becontrolled by treating the soil with sulphur inoculated with Thio-bacillus thio-oxydans, the acidity produced by the oxidation of thesulphur being sufficient to inhibit the growth of Actinomycesscabies, the organism responsible for the disease.6* Similarly, thealkalinity of “black alkali ” soil can be reduced by treatment6o V. Vincent, Compt. rend., 1922, 175, 1233.61 E.A. Fisher, loc. cit.; see also C. H. Spurway, Michigan Agric. Exp.62 0. Arrhenius, loc. cit., and Soil Sci., 1922, 14, 223.63 Ann. Reporte, 1920,17, 178 ; see also J. Hudig and C. W. G. Hetterschij,64 N. M. Comber, J. Agric. Sci., 1922, 12, 370.65 R. H. Carr, J . Ind. Eng. Chem., 1922, 13, 931; A . , i, 172.6 6 I. A. Denison, Soil Sci., 1922, 13, 81 ; A., i, 512.67 E. M. Crowther, Trans. Paraduy Soc., 1922, 17, 317.6 * S. A. Waksman, Soil Sci., 1922, 14, 61; see also W. H. Martin, ibid.,Sta., Technical Bull. No. 57; October, 1922.Chem. Weekblad, 1922, 19, 366; A., i, 1104.1921, 11, 75214 ANNUAL REPORTS ON THE PROGRESS OF C~MISTRV.with inooulated sulphur, although it is also necessary to leachout the salts if the full benefit is to be obtained.69T h e .E f f e c t of S o i l C o n d i t i o n s a n d of F e r t i l i s e r so n P l a n t Growth.In the first section of this Report, the work of the past year hasbeen considered in relation to the influence of the various soilfactors on the soil solution; in this section, the relation of the soilsolution to the growth of the plant will be discussed.The eflect of the concentration of the soil solution on plant growthis a question which is a t present but little understood. The usuallyaccepted view is that the plant root absorbs nutrient ions from thesoil solution by osmosis. On this view, there will probably be forany plant a minimum concentration for each ion, below which theplant is unable to absorb that ion.The minimum value will varyfor different ions and for different plants. The lack of knowledgeas to the values of these minima is partly responsible for thedifficulty of interpreting the results of soil analysis in terms ofsoil fertility. Vesterberg ' 0 has discussed this point, and from anexamination of various data he has put forward tentative averagevalues for these minima for nitrogen, potash, and phosphate. Whenthe requirements of any plant have been ascertained, it will thenbe necessary to find, for any given soil, (1) whether it can give therequired concentration in the soil solution and (2) whether it canmaintain it. Comber,71 however, advances an interesting modifica-tion of the present osmotic hypothesis of the mechanism of rootabsorption in the soil.He maintains that the assumption that plantsfeed in the soil just as they feed in water cultures is unjustified andcontrary to the facts. He adduces evidence in favour of the viewthat colloids can be directly absorbed by the plant, and advancesthe hypothesis that there is a direct union of the root hair withthe particles of the soil; this union is brought about by colloidalmucilaginous matter from the cell wall of the root hair on the onehand, and the hydrophilous gel coating around the soil particleon the other, which intermingle to form one system, therebyenabling the direct absorption of colloids, and permitting the acidjuices of the plant cell to attack direotly the particles of the soil.The acceptance of this hypothesis would, of course, necessitate aradical reconsideration of our views regarding the relation of thesoil solution to the plant.The efect of the composition of the soil solution on plant growth7o H.A. Vesterburg, Internat. Mitt. Bodenkunde, 1922, 12, 11.W. Rudolfs, Soil Sci., 1922, 13, 215.N. M. Comber, J. Agric. Sci., 1922, 12, 363AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 215may next be considered. Besides the ammonium salts and nitratesproduced by biological agencies in the soil, it is concluded from astudy of the action of a h l i n e permanganate that the nitrogenpresent in the soil as amino-acids, and part of that present asacid amides, are immediately available.72 It is doubtful, however,whether such substances are normally present in sufficient amountto be of importance.Some American soils seem to be actually deficient in sulphates,so that they give increased crops by treatment with sulphur.73For this treatment to be successful, the dressings must be small,otherwise if the oxidising power of the soil is high and the soil notwell buffered, the hydrogen-ion concentration is increased to apoint at which the plant suffers.74The utilisation of phosphates varies for different species ofplants, and appears to bea>r a direct relation to the ratio CaO : P,O,in the ash of the Ammonium humate or colloidal humicacid is stated to increase the solubility of mineral phosphates andthus to give rise to increased phosphate a~similation.~~ It is alsostated that the same effect is obtained by the active nitrification ofurea,77 thus supporting the suggestion of Lantzs~h.'~ It is notpracticable to render mineral phosphates more soluble by directapplication of sulphur to the soil, since the hydrogen-ion concen-tration required to effect the transformation (pH 3.1-2.8) is harmfulto plants.79 In the Rothamsted field experiments, it has long beenfound that increased yields are obtained on phosphate-defioientsoil by the application of sodium silicate, and it is usually supposedthat this effect is due to increased assimilation of phosphate in thepresence of silica.Lemmermann and Wiessman 80 have obtainedsimilar results in pot experiments using colloidal silica, but theyobtained significant increases also in the complete absence ofphosphates, from which they conclude that colloidal silica has a72 C.S. Robinson, 0. B. Winter, and E. J. Millar, J . Ind. Eng. Chem.,1921, 13, 933; A., i, 212.73 See, for example, F. C. Reimer and H. V. Tartar, Oregon Agric. Exp.Sta., Bull., 163, 1919; also J. Woodard, Bot. Gaz., 1922,1S, 81.74 W.Rudolfs, Soil Sci., 1922,14,247 ; see also J. S. Joffe and H. C. McLean,&id., 217. For German experience see B. Heinze, 8. Pflanz. Diing.,1922, [ A ] , 1, 154; E. Kmger, ibid,, 166; Gerlach, Mitt. Deut. landw. Ges.,1921, 36, 726.75 M. von Wrangell, Landw. Jahrb., 1922,57,1; A., i,'1098.7 6 K. Mack, Chem. Ztg., 1922,46, 73.7 7 J. S. Marais, Soil Sci., 1922,13, 355.7v W. Rudolfs, Zoc. cit.*O 0. Lemmermann and H. Wiessmann, 8.Pflanz. Diing., 1922, [ A ] , 1,K. Lantzsch, loc. cit.185; A., i, 1103216 ANRTJAL REPORTS ON THE PROGRESS OF CHEMISTRY.direct effect on plant growth, and that it acts in the presence ofphosphate deficiency by virtue of an ability partly to replacephosphate in the plant. They do not appear, however, to havedetermined the amounts of phosphate and silica taken up by theincreased crops ; this would throw light on the relative importanceof the supposed direct action of the silica on the plant and of itspossible indirect action in causing increased assimilation of phos-phates. Shedd 81 has also obtained increased growth by theapplication of silica.One of the effects of potash on the plant is to increase its vigour,and its resistance to disease. This is well instanced by a resultreported from Arkansas; 82 on a control plot receiving no potash,95 per cent.of the cotton plants died from the wilt disease, whereason the plot receiving kainit not a single plant was affected.Experiments in Kentuckym indicate that some soils may bedeficient in calcium, and that by the application of salts of thismetal, crop increases may be obtained which are not due merelyto decreased hydrogen-ion concentration.The eflect of the reaction of the soil solution on plant growth isgradually being elucidated. Sour soils are recognised agriculturallyby well-defined symptoms, such as the growth of certain charac-teristic weeds, the liability of cruciferous crops to " finger and toe "disease, and the failure of most leguminous crops.It does notfollow, however, that a soil which is " acid " according to chemicaltests is " sour " in the agricultural sense; the hydrogen-ionconcentration which is definitely harmful varies greatly for differentcrops,84 and under undisturbed natural conditions the characterof the flora may be largely influenced by the reaction of the soilsolution.86 Most common crop plants appear to be unaffected by,and even possibly to prefer, a faintly acid medium. Thus it hasbeen shown 86 that although peas, maize, wheat, oats, and carrotsall germinated most slowly at hydrogen-ion concentrations ofp , 5-6, root growth after ten days was at a maximum betweenthese values, which are regarded as representing the values fornormal growth.There is always a tendency, when a plant is0. 31. Shedd, Soil Sci., 1922, 14, 233.82 L. E. Rast, J . Amer. SOC. Agron., 1922,14, 222.8s 0. M. Shedd,.Zoc. cit., and Kentucky Agr. Exp. Sta. Bull., 236 (1931);84 See, for example, 0. Lemmermann and L. Fresenius, loc. cit.86 E. J. Salisbury, Ann. Bot., 192.2, 36, 391 ; A., i, 1104; W. R. G. Atkins,Nature, 1921, 108, 80; A., i, 415; Sci. Proc. Roy. Dubl. SOC., 1922, 16, 369;A., i, 509; A. P. Kelley, Soil Sci., 1922,13,411; C . Olsen, Science, 1921, M, 539.86 R. M. Hixon, Medd. K . vetenskapsakad. Nobel-Inst., 1922, 4, No. 91 ;A., i, 1221; see also 0. Arrhenius, J . Gen. Phyeiol., 1922, 5, 81; A., i, 1097.A., ii, 627AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 21 7growing in a solution with a hydrogen-ion concentration towardsone extreme, for the plant to modify this value towards one lyingbetween pH 5.0 and 6.8.The cell-sap of many plants is acid,87and it has been found that plants may tend to alter the acidityof the soil solution so as to bring it closer to that of their own rootsap.88 On the other hand, the acidity of the plant juices may bedirectly influenced by that of the soil s0lution.8~ The harmfuleffect of sour soils may often be due not so much to the acidity ofthe soil solution as to the soluble iron and aluminium compoundsthey contain.90 Soil acidity may also affect soil fertility indirectlyby its deleterious effect on many of the micro-organisms concernedin the nitrogen cycle. Thus nitrification is hindered by acidity:a case is reported where a strong nitrite reaction developed in asoil a t pH 3.94*4,91 whilst in another instance, it was found thatthose acid soils which responded to lime in the field were the onesin which lime treatment caused a rapid formation of nitrates.92Growth of, and nitrogen fixation by, Axotobacter are inhibited byacidity higher than p H 5-9-6*0.93The efSeect of partial sterilisation of the soil by arsenates andarsenites 94 and by various aromatic substances 95 has been studied.Russell and Hutchinson’s view of the mechanism of partialsterilisation is that the sterilising agent kills off the soil protozoa,which normally limit the numbers of beneficial bacteria in the soil,and thus enables the latter t o attain greatly increased numbersand to produce increased quantities of plant nutrients.96 Muchdiscussion has centred round this hypothesis.From an experimenta t Rothamsted in which the numbers of active amebae and ofbacteria in a field soil were counted daily for 365 days, it has beenclearly established that there is a definite inverse relationship8 7 See, for example, W. R. G. Atkins, Sci. Proc. Roy. Dubl. SOC., 1922, 16,414; A . , i, 411.8 8 J. Konig, J. Hasenbaumer, and E . Kroger, 2. PfEunz. Diing., 1922, [ A ] ,1, 3 ; A . , i, 510.F. C. Bauer and A. R. C. Haas, Soil Sci., 1922,13, 461; A., i, 975.S. D. Conner and 0. H. Sears, ibid., 23; A., i, 613; N. M. Comber,Nature, 1921, 108, 14G; A., i, 416; C. H. Arndt, Arner. J . Bot., 1922, 9,47; A., i, 1103.91 F.C. Gerretsen, Arch. Suikerindus. Nederland-Indie, 1921, 29, 1397 ;Exp. Sta. Rec., 1922, 47, 214.93 R. H. Robinson and D. R. Bullis, Soil Sci., 449; A., i, 976.p3 P. L. Gainey and H. W. Batchelor, Science, 1922, 56, 49; A., i, 1096.D4 G. Rivikre and G. Pichard, Compt. rend., 1922, 174, 493; R. Ciferri,96 T. Parker, A. W. Long, and J. S. Mitchell, Bull. Bur. Bio-Tech., 1922,96 F,. J. Russell and H. B. Hutchinson, J . -4yric. Sci., 1909, 3, 111; 1913,Coltivatore, 1922, Nos. 32-34.No. 5, 134.5, 152218 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.between the numbers of these two types of organisms : when thenumbers of active amoebae are high, those of the bacteria are low,and vice versa; 97 these results lend very considerable support toRussell and Hutchinson’s hypothesis, and show that howevermany factors there may be which play a part in partial sterilisation,the elimination of the protozoa by the process is by no means theleast important.The relation of crop yield to amount of fertiliser used, and Mitscher-lich’s application thereto of the “ law of minimum ” still provokecontroversy in Germany.gs The question is of considerable practicalimportance, particularly a t a time of agricultural depression suchas the present. There are now some indicationsg9 that at firstincreasingly large crop increments may be obtained by successiveequal increases in the amount of fertiliser used, and that only withrelatively large dressings does the “ law of diminishing returns ”come into play; the curve for the relation of yield to amount offertiliser appears to be sigmoid rather than logarithmic in form.T h e C h e m i s t r y of P l a n t P r o c e s s e s .Having discussed the soil and the influence on plant growth ofsoil factors, including the nutrient materials derived from the soil,it remains to deal with the processes going on within the plantitself.Carbon Assimilation.The striking investigations of Baly and his co-workers on thephotocatalytic mechanism of the photosynthesis of carbohydrateshave now been extended to the production of nitrogen compounds ;this work is discussed later in this section.The photoelectricproperties of chlorophyll, and their bearing on the electronic theoryof sensitisation, have received further a t t e n t i ~ n .~ The energychanges accompanying carbon-dioxide assimilation (by the greenalga, ChloreZla vulgaris) in artificial light, and the percentage utilis-ation of energy in different parts of the spectrum have been ~tudied.~9 7 D. W. Cutler, L. M. Crump, and H. Saudon, Phil. Trans., 1922, [BI,211, 317.98 E. A. Mitscherlich, Landw. Versuchs-Stat., 1922, 99, 133; A. Rippol,J . Landw., 1922, 70, 9.9s E. J. Russell, J . Min. Agric., 1922, 29, 752, 836.1 E. C. C. Baly, I. M. Heilbron, and W. F. Barker, T., 1921, 119, 1025;2 E. C. C. Baly, I. M. Heilbron, and D. P. Hudson, T., 1922, 121, 1078.9 H. H. Dixon and N. G. Ball, Sci. Proc. Roy. Dubl. SOC., 1922,16* 435;A., ii, 248.0. Warburg and E. Negelein, 2. physikal.Chem., 1922,102, 235; A.,i, 1097; C. Muller and 0. Warburg, Ber. Physika1.-Tech. Reichsanst., 1920,A., i, 411.see also E. C. C. Baly, J. Soc. Dyers & Col., 1922, 38, 4; A., i, 307AGRICULTURAL CHEMISTRY AND VEGETAELE PHYSIOLOGY. 219Kostytschev has published a series of investigations on photo-synthesis. He fbds that the ratio CO,/O, is disturbed in atmo-sphere8 containing abnormally large amounts of carbon dioxide,being first greater and then less than unity. I n such atmospheres,leguminosae assimilate markedly more carbon dioxide than otherplants do. Assimilation is increased by the presence of nitratesin the soil. It has been shown that leaves of Tropmolum majuscan assimilate formaldehyde vapour.6 The supposed formation ofhydrogen peroxide in the assimilation of carbon dioxide by plantscould not be confirmed,8 neither could the statement that leavesfloating on sugar solution in sunlight are able to synthesise phloro-glucinol be substantiated.10 The possibility of obtaining sub-stantial crop increases by artificial enrichment of the atmosphereby carbonic acid, which has aroused so much interest in Germany,lldemands for its successful realisation that due regard be paid tothe other controlling factors such as light, moisture, etc.x2Carbohydrate Metabolism and Translocation.Tho disappearance of starch from leaves kept in the dark isfavoured by dry conditions, and results in the production of non-reducing substances.13 In the case of TropEoZum majus, sucroseseems to be the product f0rrned.1~ The leaves of Fagus sylvuticaand Esculus Hippocastanum, however, when they turn yellow anddie, suffer a diminution in their content of soluble carbohydrate,and an increase in their insoluble but readily hydrolysed carbo-hydrate.15 From an investigation of the changes and movementsof carbohydrates in Mercurialis perennis during its annual growth,it is concluded that there is another dextrorotatory substancepresent in addition to sucrose, though attempts to isolate it haveso far failed.16 The changes in the pectic constituents of applesduring the ripening process have been investigated.17 Solublepectin is a t a maximum when the fruit is ripe.808; ibid., 1922, 40, 112; A , , i.613.G. Kostytschev, Ber. Deut. bot.Gaz., 1921, 39, 319, 328, 334; A, i, 307,M. Jacoby, Biochem. Z., 1922, 128, 119; A, i, 502. A., 1918, ii, 107.Waage, Ber. Deut. bot. Qee., 1890, 8, 260; A . , 1891, 606.* H. Molisch, ibid., 1921, 125, 257; A., i, 411.lo M. Nierenstein, Nature, 1920, 105, 391.l1 Ann. Reports, 1921, 18, 209.l2 Densch, Z . Pflanz. Dung., 1922, 1, 32.l3 H. Molisch, Ber. Deut. bot. Ges., 1921, 39, 339; A., i, 309.l4 H. Sohroeder and T. Horn, Biochern. Z . , 1922,130, 166; A., i, 90G.l6 R. Combes and D. Kohler, Compt. rend., 1922, 175, 690; A, i, 1222.lG P. Gillot, J. Pharm. Chim., 1922, [vii], 26, 250; A., i, 1101.I f M. H. Card, Biochem. J., 1922, 16, 704; A., i, 1222; see also M. H.Carre and D. Haynes, ibid., 60; A . , i, 401220 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The quantitative investigation of the movements and changesof carbohydrates in plants would be much facilitated by the dis-covery of a quick and trustworthy method of starch estimation.A method which promises to satisfy these requirements has beendescribed.18Nitrogenous Assimilation and Metabolism.Very suggestive results have been obtained by Baly, Heilbron,and Hudson l9 in an extension of their work on photocatalysis tothe formation of nitrogen compounds. Setting out from theobservation of Schimper *O that nitrites are always present inthe living leaf in the dark, but that they disappear when the leafis in the light, provided chlorophyll is present ; and from theobservation of Baudisch that formhydroxamic acid is formedwhen an aqueous solution of potassium nitrite containing methylalcohol is exposed to ultra-violet light, these investigators haveshown that activated formaldehyde-such as is produced by theaction of ultra-violet light of very short wave-length (A = 200 pp)on an aqueous solution of carbon dioxide, or of ordinary light ona similar solution containing a photocatalyst such as chlorophyll-readily combines with potassium nitrite to give formhydroxamicacid, which can at once react with more molecules of activatedformaldehyde to produce a great variety of complex substancessuch as are found in the living plant.These reactions take pre-cedence of the photocatalytic polymerisation of activated form-aldehyde to form reducing sugars; the latter only occurs when theactivated formaldehyde is produced a t a rate greater than that a twhich it can react with potassium nitrite and with the form-hydroxamic acid thus formed.These investigators have no doubtthat formhydroxamic acid marks the first stage in the photo-synthesis of the nitrogen compounds found in the plant. Thereaction may be formulated thus :+ o H-C-OH - H-c-OHN-OK I I H-C-OH + O=N-OK = O=X-OK -Activatedformaldehyde.Formhydroxamic acid(potassium salt).They have obtained definite evidence of the formation of a-amino-acids, of a crystalline alkaloidal base, of a crystalline base closelyresembling and possibly identical with glyoxaline, and of a sub-l8 A. R. Ling, J . Inet. Brewing, 1922, 28, 838; A., ii, 879.2o Schimper, Bot.Z., 1888, 46, 65.*1 Baudisch, Ber., 1911, 44, 1009.work, see J . Biol. Chem., 1921, 48, 489; A,, i, 194.E. C. C. Baly, I. M. Heilbron, and D. P. Hudson, Zoc. cit.For a recent summary of Baudisch'AGRICULTURAL CHEMISTRY AND VEGETABLE PHPSIOLOQY. 22 1stituted a-amino-acid which may be histidine. They show howthe production of these, and of other nitrogenous plant products,by the interaction of activated formaldehyde and formhydroxamicacid, is readily explicable. The following scheme is put forwardby them with some confidence as an indication of the main linesalong which this photosynthesis takes place :Potassium nitrate Carbonic acid.Potassium nitriteJ. J/I .5.Activated formaldehyde9Formhydroxamic acidI --- 1+ Hexosesa- Amino-acids + Nitrogen bases~ ___ IJ.+J f -Alkaloids and xanthinederivatives Substituted a-amino-acids(Histidine, etc.)ProteinsThe far-reaching importance of this work can best be emphasisedby the following quotation : 22" The activated formaldehyde produced by the photocatalyticaction of chlorophyll on carbonic acid combines with the potassiumnitrite known to be present in the leaves, this reaction takingprecedence of all others.The formhydroxamic acid then con-denses with more activated formaldehyde, this reaction takingsecond place in the order of precedence, whilst all excess of theactivated formaldehyde polymerises to form hexoses.' I The interaction of the activated formaldehyde with form-hydroxamic acid follows two main lines, the formation of amino-acids and of various nitrogen bases.These nitrogen bases consistof various types, namely, pyrrole, pyridine, and glyoxaline, whichby further condensation with activated formaldehyde give indole,quinoline, isoquinoline, and xanthine derivatives, In cases wheresuch is possible these bases condense with the amino-acids to givethe substituted amino-acids such as histidine, tryptophan, etc.The excess of nitrogen bases undergoes further condensation togive alkaloids, whilst the substituted amino-acids interact to giveproteins. The readiness with which all these reactions take placeis due to the cardinal fact that the various compounds are produced22 E. C. C. Baly, I. M. Heilbron, and D. P. Hudson, Zoc. cit., p.1087222 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in highly reactive phases, analogous to the highly reactive phaseof formaldehyde when photosynthetically formed. This reactivityenables condensations to occur which are otherwise impossible torealise in the laboratory. It is a matter of common knowledgethat these reactions must occur in the living plant, and our resultsshow that the key to the problem is the enhanced reactivity offreshly synthesised molecules. . . . The synthesis of the nitrogencompounds found in the plant is not photosynthetic except in sofar as the production of the activated formaldehyde by the chloro-phyll is concerned. The various amino-acids, proteins, alkaloids,etc., are natural and indeed inevitable results of the photosynthesisof formaldehyde in the presence of potassium nitrite.. . .“. . . . A further conclusion of importance is that the regionwhere the synthesis occurs must necessarily be restricted to theleaves. Since it must not be forgotten that the synthesis of hexosesis taking place concurrently, the conditions are perfect for theformation of glucosides and we believe that the products of thenitrogen synthesis are translocated as soluble glucosides. The factthat nitrogen derivatives are found in other parts of the plantcannot be accepted as an argument that they must have beensynthesised in those parts. There can be no doubt that thesynthesis takes place in the leaves and that the compounds aresubsequently distributed as soluble glucosides by the normaltranslocatory processes.’’Ever since the classical experiments of Boussingault and ofLawes and Gilbert, it has been generally accepted that green plantsare entirely dependent for nitrogen on the supplies they receivethrough their roots in the form of nitrates, ammonia, and possiblyother forms, and that none caa assimilate the elemental nitrogenof the air, although the leguminous plants are able to live insymbiosis with a, nitrogen-fixing bacillus, and therefore are able tolive without combined eitrogen from other sources.From timeto time the claim has been advanced that green plants are able tofix nitrogen, but the evidence has never been free from suspicion.During the past year two further claims have been advanced,both from America. As already mentioned, one of the~e,~3 onbehalf of the unicellular green algae, is open to question.Theother claim is on behalf of that possibly most investigated of allagricultural plants, the wheat plant. Only a preliminary note hasso far appeared 24 and details will be awaited with great interest.Whilst no one would lightly deny the possibility of nitrogen fixationby green plants, the great bulk of agricultural experience is against23 F. B. Wann, Eoc. cit.24 C. B. Lipmann and J. K. Taylor, Science, 1922 S6, 605AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLO~Y. 223the likelihood of its occurrence, and until conclusive and infallibleevidence is advanced, the case remains as heretofore-" notproven."Further work has been carried out on the nitrogenous metabolismof the runner bean; 25 one of the active enzymes appears to beasparaginase.In Vicia sativa, and also possibly in Angelicasiluestris and Trifolium pratense, arginase is present .26In general, the later nitrates are applied to cereals, the higheris the protein content, and the greater the hardness, of the grain.27It is held that in the germinating seed of Helianthus annuusamino-acids and proteins are oxidised with formation of ammonia,which is used by the plant in the synthesis of asparagine andgIutamine.28For the formation of alkaloids by the blue and yellow lupines,nitrogenous fertilisers seem to be less suitable than the nitrogenouscompounds produced by the nodule bacteria, judging by thealkaloid content of plants.29 Ciamician and Ravenna have pub-lished a summary of their work since 1908 on the biologicalsignificance of alkaloids in pIants.30Osmotic and Allied Phenomena.The permeability of plant cells, the imbibition of water by plantcolloids, and similar osmotic processes undoubtedly have a funda-mental bearing on the phenomena of root absorption, transpiration,translocation, etc.A considerable amount of work still appearson these t o p i ~ s , ~ l but the subject is as yet in rather a confused state,and does not lend itself to brief discussion here. Mention may,however, be made of a suggestive article by Shul132 on osmotic-4., i, 1225.25 A. C . Chibnall, Biochem. J., 1922, 18, 344; A., i, 908; ibid., 599, 608;26 A. Kiesel, Z . physiol.Chem., 1922, 118, 254, 267; A., i, 412, 413.2 7 W. F. Gericke, S ~ i l Sci., 1922, 14, 103; A., i, 1226; see also J. Amer.2 8 A. Oparin, Biochem. Z., 1921, 124, 90; A., i, 309.29 Vogel and E. Weber, Z . Pflanz. Diing., 1922, [ A ] , 1, 8 5 ; A., i, 798.30 C. Ciamician and C . Ravenna, Biochem. terap. 8perim., 1922, 9, 3 ; A.,i, 797.31 Permeability : W. J. V. Osterhout, J. Qen. Physiol., 1921, 4, 275; A.,i, 308; M. M. Brooks, ibid., 347; A., i, 308; H. Kahho, Biochem. Z . ,1921, 123, 284; A., i, 308; H. P. Moller, Koll. Chem. Beihefte, 1921, 14,97; A., i, 95. Imbibition : D. T. MacDougall, Proc. Amer. Phil. Soc., 1921,60, 15; A., i, 204. Root abeorption: G. M. Redfern, Ann. Bot., 1922, 36,167; A., i, 614; J. Stoklasa, Bwchem. Z . , 1922,128,35 ; A., i, 502 (aluminium).E8ect of salts on plant protoplasm : H.Hahho, Biochem. Z . , 1921, 117, 87;A., i, 94; ibid., 1921, 120, 125; A . , i, 205; ibid., 1921, 122, 39; A., i, 311;W. Brenner, Hyllningsskriftillagnad Ossian Aschan, 1920, 36; A., i, 907SOC. Agron., 1922, 14, 311; also J. Davidson, ibid., 118.32 C. A. Shull, Tmns. Faraday Soc., 1922, 17, 255224 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.phenomena in plants, and of a series of articles on permeability byStiles.= The work of Priestley and his associates 34 is worthy ofspecial mention.Stim.rdant and Toxic Agents.The favourable action of calcium salts on germination appearsto be concerned with the synthetic phase of this proc$ss.35 Leadsalts exert a toxic action on the plant.They accumulate in theroots, whose growth they especially hinder.36 The oligodynamiceffect of silver is due to the silver-ion; it can be neutralised bypotassium cyanide, which converts the deleterious silver-ion intothe Ag(cN),-i~n.~'It is stated that disodium arsenate has a stimulating action inlow concentrations, although toxic if slightly higher concentrationsare used.38 This may, however, have been an indirect, soil effe~t.3~Selenates, and particularly selenites, are markedly toxic to germina-tion and growth of plants, as well as to Axotobacter C ~ T O O C O C C U ~ ,but radium emanation is stimulating in its action on germination,and it inhibits the toxic action of selenates and ~elenites.4~ Sodiumselenate a t very low concentration is, however, stimulative tom a i ~ e . ~ lHippuric acid is toxic to plant cells a t strengths above 0.09 percent., but urea at 1 per cent.is harmless.42 Cocaine and ecgonineare very much less toxic to Lupinus albus than they are to animals,but with sodium benzoate the reverse is the case.43 From aninvestigation of the action of a large number of organic compoundsit is concluded that, for compounds containing equal numbers ofcarbon atoms, the series : Amines, alcohols, aldehydes, acids,represents the order of diminishing toxicity towards plants.4433 W. Stiles, New Phytologist, 1922.34 J. H. Priestley, ibid., 1922, 21, 41, 58, 62, 113, 210, 252.35 L. Maquenne and E. Demoussy, Compt. rend., 1922, 175, 249; A.,36 E . Bonnet, ibid., 1922, 174, 488; A., i, 412.37 R.Doerr and W. Berger, Biochem. Z., 1922, 131, 151; A., i, 1097;see also A. Luger, ibid., 1921, 117, 153; A., i, 65.38 J. Stewart and E. S. Smith, Soil Sci., 1922, 14, 119; A., i, 1222.39 See, for example, Rivibre and Pichard, Zoc. cit.4O J. Stoklasa, Compt. rend., 1922, 174, 1075; A., i, 613; Biochem. Z . ,1922, 130, 604; A., i, 974; B. Turina, ibid., 1922, 129, 507; A.,i, 707 (alsotellurium).i, 905.4l J.Stoklasa, Compt. rend., 1922, 174, 1256; A,, i, 614.42 T. Bokorny, Biochem. Z., 1922,132, 197; A., i, 1222.48 D. I. Macht and M. B. Livingston, J . Gen. Physiol., 1922, 4, 573; A.,44 G. Ciamician and A. Galizzi, Gazzetta, 1922, 52, i, 3; A., i, 503.i, 798AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY.225The toxic action of traces of coal gas on plants is due to unsatur-ated hydrocarbons (ethylene), which appear to act specially inpreventing normal root de~elopment.~~The stimulating effect of the electric discharge appears to bedefmitely established by field experiments on spring-sown oatsand barley, but this problem is still under inveetigation.46P l a n t C o n s t i t u e n t s a n d P r o d u c t s .Inorganic Constituents.Manganese, which appears to be an invariable constituent ofplants,47 is found in the greatest quantities in those parts of theplant such as the seeds, and young leaves where the chemical changesare most intense.4* It has been found,49 using many differentspecies of plants, that in a medium entirely free from manganesegrowth ceases, and the plants become chlorotic, after six or eightweeks, by which time the manganese originally contained in theseed is presumably no longer sufficient.It is suggested thatmanganese is necessary for chlorophyll formation, and that it isconcerned in nitrogen assimilation and protein synthesis, sinceleguminous plants are more sensitive to its absence.Minute traces of nickel, and, with two exceptions, of cobalt,have been found in sixteen different species of common plants.50These two elements have also been found in minute amounts intwo arable soils.51 From the fact that the amount of nickel ismuch greater than that of cobalt both in the soils and in the plantsexamined i t seems that the occurrence of these elements in theplant may be merely adventitious.Chlorine occurs in most plants, always as chloride; it is mostabundant in succulent parenchymatous tissues.Conifers, mosses,ferns, epiphytes, parasites, and saprophites contain little or nochlorine.52 Fluorine is a normal constituent of Spanish grapes.53Bied. Zentr., 1921, 50, 425; A , , i, 211.45 J. H. Priestley, Ann. Appl. Biol., 1922, 9, 146; see also C. Wehmer,'13 J . Min. Agric., 1922, 29, 792.47 D. H. Wester, Biochem. Z., 1921,118, 158; A., i, 94; Phamt. Weekblad,1922, 59, 51 ; A., i, 309; G. Bode and K. Hembd, Biochem. Z., 1921,124,84 ; A., i, 415.48 G. Bertrand and M. Rosenblatt, Compt. rend., 1921, 173, 1118; A.,i, 96; ibid., 1922, 174, 491; A., i, 411; F. JadiP and A. Astruc, BuEE. SOC.chim., 1922, 31, 917; A., i, 1098.J.S. McHargue, J . Amer. Chem. SOC., 1922, 44, 1592; A,, i, 906.G. Bertrand and M. Mokragnatz, Compt. rend., 1922, 175, 458; A.,Idem, ibid., 112; A., i, 975.i, 1099.6 z J. Jung, Sitzungaber. Akad. Wiss., 1920, 129, 297; A., i, 1098.53 M. L. Pondal, Anal. Asoc. Qdm. Argentina, 1922, 10, 67; A,, i, 1100.REP .-VOL. XIX. 226 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The amolxnt and distribution of inorganic and organic phosphatesin various seeds have been studied.54 Marine algs generallyappear to contain a small amount of arsenic.55Organic Plant Products.Chemical work on the constitution of plant products comeswithin the scope of the Reports on organic chemistry, and is notconsidered in this Report; in this section, attention is confined tothe occurrence of the different classes of organic substances inplants, and to work throwing light on the mode of formation ofspecial classes of plant products.andthe hemicelluloses of the seed of Aspragus officinalis 5' have beenexamined.Cytopentans is the name proposed for the "hemi-cellulose "-like constituents of the cell-walls of plants.58 Animproved method for the preparation of raffinose from cotton-seedmeal has been described.59 Papers have appeared on the occurrenceand nature of the sugars and glucosides in Sedzm Telephium(glucoside of an essential Melarnpyrum arzleme (aucubin),61Rhinanthus Crista-Galli (aucubin),62 several species of O r ~ h i s , ~ ~ inthe Schrophulariacece, 64 the Caryophyllacece and Papilionacece, 65 andin Viburnum opulus, extracts of red Cinchona, and the Cola nut.66Chinese oak tannin,68 and a crystalline tannin from Acerginnala 69 have been studied.Saponins have been isolated fromCarbohydrates and G1ucosides.-The sugars of wheat64 F. Rogozinski, Bull. Acad. Scz'. Cracovie, 1915, [B], No. 5, 87; A . ,6 6 A. J. Jones, Pharm. J . , 1922, 109, 86; A . , i, 905.66 S. H. Collins and B. Thomas, J . Agric. Sci., 1922,12, 280 ; S. H. Collins,67 W. E. Cake and H. H. Bartlett, J. Biol. Chem., 1922,51, 93 ; A . , i, 504.6 8 D. H. F. Clayson, F. W. Norris, and S. B. Schryver, Biochem. J . , 1921,69 E. P. Clerk, J . Amer. Chem. SOC., 1922,44, 210; A., i, 323.60 M. Bridel, Bull. SOC. Chim. biol., 1922, 4, 242; A., i, 799; J .Pharni.china., 1922, [vii], 26, 289; A., i, 1225.61 M. Bridel and M. Braecke, ibid., 1922, 25, 449; A,, i, 799; Compl.rend., 1921, 173, 1403; A., i, 209.62 Idem, ibid., 1922, 175, 532; A . , i, 1225; see also ibid., 640; A., i,1168.63 H. HBrissey and P. Delauney, Bull. SOC. Chim. biol., 1921, 3, 573; A.,i, 210.64 M. Braecke, ibid., 1922, 4, 407; A . , i, 1225.66 C. Vergelot, &id., 1921,3, 513; A., i, 207.6 6 R. Arnold, ibid., 547; A., i, 311.67 K. Freudenberg, Ber., 1922, 55, [BJ, 2813; A., i, 1169.' 8 K. Freudenberg and E. Vollbrecht, ibid., 2420; A., i, 104G.68 A. G. Perkin and Y . Uyeda, T., 1922, 121, 66.i, 1226.J . SOC. Chem. Ind., 1922, 41, 56r; A., ii, 323.15, 643 ; A., i, 20GAGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY.227Agave lechuguilla 70 and Aralia and the effect of daylighton the content of active material in Digitalis has been examined.T2Acids and Esters.-The occurrence is recorded of citric and malicacids in Ribes rubrum; 73 of methyl anthranilate in grape juice; 74of lactic acid in Rubus idmus (with succinic acid),75 R. f r u t i c ~ s u s , ~ ~Papver sornniferum, Ricinus cornmunis, and Agare Xisalana ; 77of oxalic acid in Acacia camba.gei (as calcium salt),78 and in theleaves of elder, hawthorn, horse-chestnut, and barley; 79 and ofmalic acid in Pyrus coronaria, Rhus glabra (with gallic acid), Acersacchurum, 8o Prunus avium,81 and Pyrus aucuparia.82 The thirdoptically active form of malic acid said to be present in certainplants does not exist.83 Various esters have been identified inpeaches.84Triglycerides ; Essential Oils.-A large number of plants andvegetable products have been examined as to their content ofsubstances of these classes ; it would, however, be neither usefulnor practicable in the space available to give details here. Theindex of the Journal for 1922 should be referred to.Pigments.-Despite the definite evidence produced by Willstiitterand others, that anthocyanins are reduction products of flavones,85the known correlation of distribution of oxydases and of antho-cyanins continues to be used as an argument for the older oxidationhypothesis.86 It seems difficult to avoid the impression that oxida-tion is indeed a factor in anthocyanin formation, but it is quiteC.0. Johns, L. H. Chernoff, and A. Viehoever, J. BioZ. Chem., 1922,52, 335; A., i, 797.71 A. W. van der Haar, Ber., 1922,55, [B], 3041 ; A., i, 1168.72 0. von Dafert, Bied. Zentr., 1921, 50, 422; A , , i, 97.73 H. Franzen and E. Schumacher, 2. phy8ioZ. Chem., 1921, 115, 9; A.,74 F. B. Power and V. K. Chesnut, J. Arner. Chem. SOC., 1921, 43, 1741;75 H. Franzen and E. Stern, 8. physiol. Chem., 1922, 121, 195; A., i, 975.7 6 H. Franzen and E. Keyssner, ibid., 1921, 116, 166; A., i, 310.7 7 H. Franzen and E. Stern, ibid., 1921,115, 270; A., i, 3J 2.7 8 T. Steel, Chem. News, 1921, 123, 315; A., i, 310.79 A. Bau, 2. tech. Biol., 1921, 8, 151; A , , i, 309.i, 310.A., i, 97.C. E. Sando and H. H. Bartlett, J. Agm'c. Bee., 1921, 22, 221; A , ,61 H.Franzen and F. Helwert, Z. phyeiol. Chem., 1922, 122, 46; A.,82 H. Franzen and R. Ostertag, ibid., 1922, 119, 150; A , , i, 116.83 Idem, ibid., 1922, 122, 263; A , , i, 1223.** F. B. Power and V. K. Chesnut, J . Amer. Chem. SOC., 1921, 43, 1726;* 5 See, for example, J. Costentin, Ann. Sci. Nat. Bot., 1919, [x], 1, 38 ;88 M. Mirande, Compt. rend., 1922,175, 595, 711; A., i, 1224.i, 100.i, 1102.A, i, 99.A., i, 162.1228 ANNUAL REPOBTS ON THE PROQRBSS OF CEEMlSTRY.possible that the two views may be reconciled on the assumptionthat oxidation is needed in the earlier stages of the synthesis, andthat only the final stage is one of reduction of flavone derivative toanthocyanin. The work of St. Jonescos7 on anthocyanins, afeature of which is his support of the oxidation hypothesis, is heldby Combes 88 to be invalidated by the fact that his (St.Jonesco's)materials are not 7-pyrone pigments but only tannins. The sappigment of the beet root is stated to be produced by oxidation of acolourless chrorn0gen.8~The presence of cyanin in the roseg0 and of pelargonin in thescarlet pelargonium 91 has been confirmed by their isolation fromvarieties not hitherto examined.The colouring matters of Lithospermum erythrorhi~on,~~ and ofseveral species of the Schixophyceag3 have been examined. It isstated that a new class of glucosidal yellow pigments-" antho-chlor )'-is represented in many plants.94PZant Proteins.-The chemical interpretation of differences inthe quality of agricultural products is a comparatively untouchedfield, of great importance.A suggestive investigation 95 on thedifference between the " strong " Canadian wheats and the '' weak "English wheats has brought out the interesting fact that there isa difference between the glutenins of these two wheats, which ismanifested by an examination of their racemisation curves. Theproteins of the Adsuki bean (PheoZus angulari~),~~ the Lima bean( P . Zunatus),97 of the seed of the tomat0,~8 of buckwheat,99 lucerne'lSorghum vuZgare,2 and of cotton seed meal, the soja bean, and thecocoa-nut have been examined.8 7 St. Jonesco, Compt. rend., 1921,113, 850, 1006; A., i, 97; ibid., 1922,174, 1635; A., i, 797; ibid., 1922,175, 592; A., i, 1224.*8 R. Combes, ibid., 1921,174, 58; A., i, 206; ibid., 1922,174, 240; A.,i, 412.89 A. Kozlowski, ibid., 1921,173, 855; A., i, 97.90 G.Currey, Proc. Roy. SOC., 1922, [ B ] , 93, 194; A., i, 413.Dl 0. Currey, T., 1922,121, 319.92 R. Majima, and C. Kuroda, Acta Phytochim., 1922,1, 43; A., i, 946.93 K. Boresch, Biochem. Z., 1021,119, 166; A., i, 210.94 G. Klein, Sitzungaber. Akad. Wias. Wien, 1920,129, 341 ; A., i, 1099.95 H. E. Woodman, J. Agric. Sci., 1922,12, 231.96 D. B. Jones, A. J. Finks, and C. E. F. Gersdorff, J. Biol. Chem., 1922,97 D. B. Jones, C. E. F. Gersdorff, C. 0. Johns, and A. J. Finks, ibid,,98 C. 0. Johns and C. E. F. Gersdorff, ibid., 1922, 51, 439; A., i, 800.89 A. Kiesel, 2. phyaioz. Chem., 1922, 118, 301; A., i, 412.61, 103; A., i, 504.1922,53,231; A., i, 1101.1 T.B. Osborne, J. Wakeman, and C. S. Leavenworth, J . BioZ. Chem.,1921, 49, 63; A., i, 99; ibid., 1922, 53, 411; A., i, 1104; H. G. Miller, J .Amer. Chem. SOL, 1921,43,2656; A,, i, 414.a 8. Visco, Arch. Pam. sperim. Xci. ag., 1921, 31, 173; A., i, 211.3 W. G. Friedemann, J. Biol. Chem., 1922, 51, 17; A., i, 605AGRICULTURAL CHEMISTRY AND VEGETABLE PRYSIOLOGY. 229Plant Bases.-The alkaloid of the yew (Taxus baccata) has beenisolated4 and the relations between the alkaloids of the calumbaroot have been el~cidated.~ The alkaloid content of belladonnaplants is increased by keeping them in the dark.6 Natural mus-carine has now been isolated in the pure state from Amanda mus-curia, and it has been shown to be a base of greater complexitythan choline or betainealdehyde.'General.-The composition of a large number of other plants hasheen studied, but it is not possible to give details here.The indexof the Journal for 1922 should be consulted.T h e C h e m i s t r y of F e r m e n t a t i o n a n dEnzyme Action.It is not possible in the remaining space to deal with this subjectfully. A brief survey of last year's work in this field, which makesno pretence to be exhaustive, will be given; a full discussion ofthe subject is reserved for a later occasion. Useful reviews ofrecent German work were given a t the recent meeting of theNaturforscherversammlung at Leipsig.7QFermentation of Carbohydrates and Allied Substances.-Neuberg'sview as to the importance of pyruvic acid in fermentation, althoughchallenged,* has received further c~nfirmation.~ Fernbach haspublished a useful review of present views on the r61e of acet-aldehyde.10 Neuberg's second mode of fermentation has nowbeen realised with various fungi l1 and with carbohydrates otherthan glucose.12 Patents for the industrial preparation of glycerolby fermentation have now been published.I3 The third and fourthforms of fermentation, by which acetic and butyric acids areproduced, as well as various other types of acid fermentation, have4 E.Winterstein and D. Iatrides, 2. physa'ol. Chent., 1921, 117, 240; A.,5 E. Spath and K. Bijhm, Ber., 1922, 55, [BJ, 2985; A., i, 1174.6 J. Ripert, Compt. Tend., 1921, 173, 928; A., i, 96.7 H. King, T., 1922, 121, 1743.7s H. von Euler, Ber., 1922, 55, [B], 3583 ; R.Willstlitter, &id., 3601 ; C.8 J. Kerb and K. Zeckendorf, Biochenz. Z., 1921, 122, 307; A., i, 305.9 M. von Grab, ibid., 1921, 123, 69; A., i, 306.10 A. Fernbach and M. Schoen, Bull. Inst. Pasteur, 1920, 18, 385; A.,l1 C. Neuberg and C. Cohen, Biochem. Z., 1921,122, 204; A., i, 304.l8 M. Tomita, ibid., 1921, 121, 164; A., i, 307; see also H. Kumagawa,ibid., 1922, 131, 148 ; A., i, 972 ; E. Abderhalden, Permentforsch., 1921,5, 89, 110; A., i, 92; 0. Fernhdez and T. Garmendia, Anal. 2748. Q u h ,1921,19, 313; A., i, 405.13 Vereinigte Chemische Werke Akt.-Ges., D.R.-P. 343321 and 347604 ;A., i, 980.i, 572.Neuberg, ibid., 3624.i, 203230 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.evoked considerable research.l4 The curious action of carboligasehas been further studied,15 also the fermentation of lactic acid byyeast.16 The stimulating l 7 and toxic l8 effects of various agentson yeast fermentation and on various bacteria,19 and moulds 20have been studied. The claim that fermentation can be effectedby mixtures containing peptone,21 although confested,22 appearsto be justified, it being stated that dextrose is converted quanti-tatively by peptone at 37" into inactive lactic acid, using sodiumbicarbonate as a, buffer.23The fermentation of inulin by Monilia macedoniensis may beused in a scheme for the identification of that carbohydrate by amycological rneth0d.~4 In the attack of pentoses by moulds,14 Acetic acid : H.Kumagawa, Biochem. Z., 1921, 123, 225; A., i, 305;E. Aubel, Compt. rend., 1921, 173, 1493; A., i, 201. Butyric acid : C.Neuberg and B. Arinstein, Biochem. Z., 1921, 117, 269; A,, i, 91; M. M.Brooks, J. Ben. Physiol., 1921, 4, 177; A . , i, 201. Lactic acid : W. H.Peterson, E. B. Fred, and J. H. Anderson, J. Biol. Chem., 1922, 53, 111;A., i, 971; 0. R. Brunkow, W. H. Peterson, and E. B. Fred, J. Amer. Chem.Soc., 1921, 43, 2244; A., i, 312 (Sauerkraut). Silage : A. Amos and H. E.Woodman, J. Agric. Sci., 1922, 12, 337. Inositol fermentation : J. A. Hewittand D. B. Steabben, Biochem. J., 1921,15, 665; A . , i, 406; H. Kumagawa,Biochem. Z., 1922, 131, 157; A . , i, 972. Citromyces : W. Butkewitsch, ibid.1922,129, 455, 464; A., i, 707; ibid., 1922,131, 327, 338; A ., i, 973. Othera c i d s : T. Yabuta, J . Chem. SOC. Tokyo, 1916, 37, 1185, 1234; A . , i, 939(Aspergillus oryzce) ; 12. Molliard, Compt. rend., 1922, 174, 881 ; A., i, 61 1(Aspergillus niger). Acetone and butyl 'alcohol : G. C . Robinson, J. Biol,Chem., 1922,53, 125; A . , i, 971.16 C. Neuberg and L. Liebermann, Biochem. Z., 1021,121, 311 ; A., i, 305;J. Hirsch, ibid., 1922,131, 178; A., i, 973.16 0. Furth and F. Lieben, ibid., 1922, 128, 144; A., i, 502; ibid., 1922,132, 165; A., i, 1219; F. Lieben, Oesterr. Chem. Ztg., 1922, 25, 87; A.,i, 796.17 C. Neuberg, E. Reinfurth, and M. Sandberg, Biochem. Z., 1921, 121,215; A., i, 306; ibid., 1921, 125, 202; A . , i, 408; ibid., 1921, 126, 153;A . , i, 408; H. von Euler and S.Karlsson, ibid., 1922, 130, 550; A., i, 972;P. Mayer, ibid., 1922,131, 1; A., i, 972; E. Lindberg, ibid., 1922,132, 110;A . , i, 1219; T. Tholin, 8. physiol. Chem., 1921, 115, 235; A . , i, 305.18 H. Plagge, Biochem. Z., 1921, 118, 129; A., i, 93; F. Boas, ibid., 1921,117, 166; A., i, 94; ibid., 1922, 129, 144; A., i, 613; R. Somogyi, ibid., 1921,120,100; A., i, 201.10 R. Cobet and V. van der Reis, ibid., 1922,129, 73; A,, i, 611 (arsenic);L. E. Walbum, Compt. rend. SOC. Biol., 1921,85,619; A . , i, 795 (manganese);T. Duboc, Compt. rend., 1922, 175, 326; A., i, 972; G. Joachimoglu, 2.Urol., 1922, 16, 97; A . , i, 1095; Laborde, Jaloustre, and 1%. Leulier, Bull.SOC. Chim. biol., 1922, 4, 415; A . , i, 1219.2o L. Plantefol, Compt.rend., 1922, 174, 123; A., i, 204.21 E. Baur and E. Herzfeld, Biochem. Z., 1921, 117, 96; A . , i, 93; ibid.,22 A. Bau, ibid., 1921, 122, 306; A., i, 307.23 G. Schlatter, ibid., 1922, 131, 362; A., i, 1096.34 A. Castellani and F. E. Taylor, Biochem. J., 1922, 16, 655; A , , ii, 879.1922,131, 382; A., i, 1097AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 231practically the whole of the carbon consumed can be accounted foras carbon dioxide and mycelium.25 Aspergillus gZuucus convertsglycerol into the methyl ether of a substance, C,H,O,, which isprobably a 7-pyrone derivative similar to malto1.26 The abilityof Fusurium lini to utilise various carbohydrates and acids has beenstudied,27 also the energy yield of the growth of Aspergillus nigeron dextrose,28 which works out a t 66-70 per cent.of that of thedextrose consumed after allowing for the maintenance requirements.Carbohydrate-splitting Enzymes.Willstatter is making a mass attack on the chemistry of enzymesand of enzyme action, and has published several lengthy papers oninvertase,29 raffina~e,~O maltase,3l l a ~ t a s e , ~ ~ and e m ~ l s i n . ~ ~ Al-though Willstatter's masterly successes in other fields of plantchemistry justify one in anticipating important results from thiswork, it is still in its infancy, and has not yet reached the stagewhen any broad generalisations emerge.The influence of conditions on the activity of the amylases presentin malt, pancreatic extract, and saliva,34 and in Aspergillus niger 35has been investigated.Euler has published several further paperson sa~charase,~~ and this enzyme has also been studied by several25 W. H. Peterson, E. B. Fred, and E. G. Schmidt, J . Biol. Chem., 1922,54. 19; A . , i, 1220.26 F. Traetta-Mosca and M. Preti, Qazzetta, 1921, 51, ii, 269; A., i, 91.27 U. Tochinoi, Ann. Phytopath. SOC. Japan, 1920, 1, 22; A., i, 207.28 E. E. Terroine and R. Wurmser, Compt. rend., 1922, 174, 1435; A , ,i, 706.2) R. Willstatter and F. Racke, AnnaEen, 1922, 427, 111; A., i, 598;R. Willstiitter, J. Graser, and R. Kuhn, 2. physiol. Chem., 1922, 123, 1; A . ,i, 1200.30 R. Willstatter and R. Kuhn, ibid., 1922, 115, lS0; A . , i, 384.31 R. Willstiitter and W. Steibelt, ibid., 1921, 115, 199; A . , i, 282; ibid.,211; A,, i, 306; R.Willstatter and R. Kuhn, ibid., 1921, 116, 53; A.,i, 283.32 R. Willstlitter and G. Oppenheimer, ibid., 1922, 118, 168; A , , i, 203.33 R. Willstatter and W. Cshnyi, ibid.. 1921, 117, 172; A., i, 390; R.Willstatter and G. Oppenheimer, ibid., 1922, 121, 183; A., i, 959.s4 D. Maestrini, Awh. Parm. sperim. Sci. aff., 1921, 32, 40, 49, 99, 126;A., i, 507, 508; R. Lecoq, J . Pharm. China., 1922, 25, 18; A., i, 312; F,DuchAdek, Chem. Listy, 1922, 16, 202; A., i, 974; H. C. Sherman, CamegieInst. Waehington Yearbook, 1919, 18, 328; A., i, 66; H. C. Sherman andM. Wayman, J . Amer. Chem. SOC., 1921,43,2464; A., i, 282; H. C. Shermanand F. Walker, ibid., 2461; A . , i, 283; U. Olsson, 2. physiol. Chem.,1921, 117, 91; A., i, 390; E. Ernstram, ibid., 1922, 119, 190; A., i, 599.36 a.L. Funke, Proc. K . Akad. Wetensclz. Amsterdam, 1922, 25, 6; A . ,, 796.a6 H. v. Euler and Svanberg, 2. physiol. Chem., 1921, 114, 137; A,, i, 284;H. v. Euler and K. Myrbilclc, ibid., 1922, 120, 61 ; A., i, 693 ; H. v. Eulerand D. Svanberg, Arkiv Kem. min. GeoE., 1922, 8, No. 12, 1 ; A . , i, 1200;H. v. Euler and K. Myrback, ibid., No. 17, 1 ; A , , i, 1201232 ANNUAL REPORTS ON THE PROGRESS O F CHEMISTRY.other investigator^.^^ The hydrolytic 38 and synthetic 39 actionsof emulsin have b6en investigated, and the isolation of activepreparations of this enzyme has been de~cribed.~O Emulsin ispresent in a new species of yeast, Willia javanica.41 Various speciesof Rhixopus contain a pectina~e.~~ The preparation of tannasefrom a mould has been de~cribed.~3Saccharophosphatase has been found in the seeds of the highercultivated plants and in the leaves of the potat0.4~ The “in-soluble ” amylase of barley has been shownby an ingenious method 45to be associated with the alcohol-soluble group of proteins (hordein).Degradation of Proteins and Arnin o - acids.Papers have appeared on the degradation of proteins by yeastY4Gon the proteolytic enzymes of malt,47 and on the bacterial degrada-tion of le~cine,~* t y r ~ s i n e , ~ ~ tryptophan, and a-naphthylalanine. 5 1Other Enzymes.A method for the preparation of castor bean lipase has beendescribed and its action studied.52 Lipase was also found in a87 W. C. Vosburgh, J . Amer. Chem. Soc., 1921, 43, 1693; A., i, 64; E. W.Miller, J. Biol. Chem., 1921, 48, 329; A,, i, 203; J. M. Nelson and D. I.Hitchcock, J . Amer. Chem. Soc., 1921, 43, 1956; A,, i, 184; ibid.,2632; A., i, 388; H. Colin and A. Chaudun, Compt. rend., 1922, 174,218; A., i, 389; A. Chaudun, J. Fabr. Sucre, 1921, 62, No. 39; A., i, 339;S. Kostyschev and P. Eliasberg, 2. physiol. Chem., 1922, 118, 233; A., i,410; E Canals, Bull. SOC. chim., 1922, [iv], 31, 921; A., i, 1076.38 J. Giaja, J. Chirn. Physique, 1921, 19, 77; A., i, 185.MI L. Rosenthaler, B’errnentforsch., 1922, 5, 334; A., i, 480; E. Norclefelclt,40 B. Helferich, 2. physiol. Chem., 1921, 117, 159; A., i, 390.4 1 J. Groenewege, Mededeel. Algemeen Proefsta. voor den Landbouw., 1921,42 L. L. Harter and J. H. Weimer, J . Agric. Research, 1921, 21, 609; A.,48 K. Freudenberg and E. Vollbrecht, 2. physiol. Clhem., 1921, 116, 277,44 A. NEmec and F. Duchofi, Biochem. Z., 1921,119, 73; A., i, 206.45 J. L. Baker and H. F. E. Hulton, T., 1922, 121, 1929.46 N. N. Ivanov, Biochem. Z., 1921, 120, 1, 25, 62; A., i, 202, 206; W.Dieter, Z . physiol. Chem., 1922, 120, 281; A., i, 795; E. Abderhalden andE. Wertheimer, Fermentforsch., 1922, 6, I ; A., i, 796.Biochern. Z., 1921, 118, 15; A., i, 66.No. 9, 1; A., i, 903.i, 607.A., i, 285.47 H. Lundin, Biochem. Z., 1922, 131, 193; A,, i, 959.‘ 8 M. Arai, ibid., 1921, 122, 251; A., i, 303.*9 F. Sieke, Z. Hyg., 1921, 94, 214; A., i, 902.6O T. Sasaki and I. Otsuka, Biochem. Z . , 1921, 121, lG7; A., i, 302.6 1 T. Sasaki and J. Kinose, ibid., 171 ; A., i, 303.62 D. E. Haley and J. F. Lyman, J. Amer. Chem. SOC., 1921, 43, 2664;A., i, 390AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 233strain of Aspergillus niger.= The production of fat from carbo-hydrate by the enzymes of oil seeds,54 by yeast,S5 and by the timothygrass bacillus 56 has been investigated.Other papers deal with the properties 57 and occurrence 58 ofurease.It is suggested that the catalase activity of seeds may be usedas an indication of their germinative capacity.59H. J. PAGE.63 R. Schenker, Biochem. Z., 1921, 120, 164; A., i, 203.64 L. Spiegel, 2. physiol. Chern., 1922, 120, 103 ; A., i, 694.65 I. S. Maclean, Biochern. J . , 1922, 16, 370; A., i, 795.6u M. Stephenson ahd M. D. Whetham, Proc. Roy. Soc., 1922, [B], 93,262; A., i, 500.67 S. Lovgren, Biochern. Z., 1921, 119, 215; A., i, 185; D H. Wester,Pharm. Weekblad, 1922, 59, 173; A., i, 391.68 A. Goris and P. Costy, Cornpt. rend., 1922, 175, 639; A., i, 1220.6@ A. NQmec and F. Duchoii, ibid., 1921, 173, 933; A., i, 94; ibid., 1922,174, 632; A., i, 411. But see J. de Vilmorin and Cezaubon, ibid., 1922,176, 60

ISSN:0365-6217    

DOI:10.1039/AR9221900203

出版商:RSC    

年代:1922

数据来源: RSC

摘要:

CRYSTALLOGRAPHY AND MINERALOGY.THE predominating thought which arises on commencing to writethis Report, on the 27th of December in the year 1922, is thatthis day is the centenary of the birth of Louis Pasteur at Dele,the picturesque little French town between Dijon and Pontarlierso familiar to travellers to Switzerland; and that the most interest-ing crystallographic research carried out during the year andactually communicated to the Royal Society this very month hasbeen the elucidation by means of X-rays of the structure of thecrystals of tartaric acid, and the confirmation in all essential detailsof the classical results of Pasteur’s first research, carried out in theyear 1848. The propriety of this happy coincidence, and thecompleteness of the proof of the accuracy of this crystallographicwork of Pasteur, will, indeed, go down to posterity as one of themost romantic events in the history of the science.It reminds usvery forcibly that the great French savant was a skilled crystallo-grapher first, and a benefactor of the human race by his wonderfulbacteriological successes afterwards.Molecules in the Crystalline Condition.In IastJ’year’s Report the writer uttered a protest against thevery premature statements which had been made by certain authors,shortly after the announcement of the first results of X-ray analysesof simple binary compounds and elementary substances, thatchemical molecules do not exist in the crystalline condition. Thewriter’s own researches had indicated exactly the contrary, andthat in most cases of chemical compounds the crystal unit, the similarrepetition of which built up the crystal and the representative pointof which formed by its repetition in space the space-lattice, wascomposed of two to four or other small number of chemical mole-cules; and that within this polymolecular crystal unit, the grosserunit of the crystal structure and the unit cell of the space-lattice,the two, four, or other small number of molecules were mutuallyarranged in such a manner that the atoms composing them weresituated so as to make up one of the 230 types of homogeneousstructure which alone are possible to crystals.Although in verysimple cases such as those of rocksalt, NaC1, and zinc blende, ZnS,the type of structnre is so very simple that molecules may not be23CRYSTALLOGRAPHY AND MINERALOQY. 235definitely identifiable, they are there all the same, for they entera8 such from the mother-liquor on crystallisation, and they areagain recoverable on solution in a solvent or on fusion to the liquidstate.In more complicated cases of substances composed of manyatoms it was inconceivable that the molecules were destroyed, onentering the crystal to assist in building up the solid edifice.The important work of Sir William Bragg on the structure ofnaphthalene and its .derivatives and anthracene, the results of theX-ray analysis of which were fully described in the last Report,gave the first experimental X-ray evidence of the truth of the writer’sviews as above expressed. For it was conclusively proved that thechemical molecules of these many-atomed organic substancesentered into the crystals intact, that the crystal-units of nnphtha-lene and anthracene are each composed of two molecules, andthat those of acenaphthene, a-naphthol, and ,%naphthol each con-tain four molecules.It was further shown that when a crystal forms in a liquid, orby sublimation, each molecule which takes part in forming thecrystal is fixed by the attachment of certain very definite pointson its own structure to certain equally specific points on the structureof another molecule, the precision of the adjustment being beauti-fully exact, indicating very definite form on the part of the molecule,and that the forces exerted have very short ranges. In the case ofnaphthalene, for instance, the molecules arrange themselves alongsideeach other, and so that the a-hydrogens of each molecule seek toattach themselves to the carbon atoms of the neighbouring mole-cules.The two molecules thus enter the crystal unit in each caseintact, and the similar repetition of this polymolecular unit, as theunit cells of a particular space-lattice, forms the crystal. For themolecules become locked into the crystal structure when attach-ments are made a t sufficient points, the whole structure being thenas definite and stable as the most perfect engineering structure.Further work during the year 1922 has united in offering additionalconfirmation of these now indisputable facts, and it was admirablysummarised, and new results referred to, in the lecture which wasdelivered to the Chemical Society on October 26th by Sir WilliamBragg.l Moreover, a definite law has been advanced by one of hiscollaborators, Mr.G. Shearer,2 as expressing the results of investi-gations carried out a t University College, London, to which furtherreference will be made later in this Report.Sir William Bragg began his lecture with the recognition of thefact that “every crystal is built up by the repetition throughoutSir W. H. Bragg, T., 1922,121, 2766.G. Shearer, Proc. Physical Soc., 1922.I* 236 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.its volume of a certain unit,” that “ the repetition is exact in everydetail, so that each unit is a perfect epitome of the whole.” Infact he adopts as correct the statement of Barlow that “ a homo-geneous structure is one, every point within which, if we regardthe structure as without boundaries, has corresponding to it aninfinitude of other points whose situations in the structure are pre-cisely similar.” Having adopted the conception of the unit cell,Sir William agrees to call it the “ crystal unit.” R.W. G. Wyckoffhas come to a somewhat similar conclusion, but has, unfortunately,given the name “crystal molecule ” to this unit polymolecularcell, which is to be deprecated as confusing, for crystal moleculeis better left to express a chemical molecule as found in the crystal.Sir William then showed that there is no reason to suppose that,in general, the crystal unit is the chemical molecule, but that thereis every reason to expect the contrary, The properties of themolecule are those of the substance in the liquid or gaseous state,whereas the solid substance possesses a large number of propertieswhich the liquid substance does not possess.There may be caseswhere the molecule is the crystal unit (some will be subsequentlyreferred to), but in general this is not so, and Sir William instancedsilicon dioxide, SiO,, the chemical molecule of which is incapable,by itself, of producing the rotation of the plane of polarisation oflight, which is so characteristic a property of quartz, the crystalliseddioxide, which X-ray analysis has shown to consist of crystalunits made up each of the substance of three molecules of SiO,.hrther, it does not follow that the molecule exists in the crystalin exactly the same form and condition as in the liquid or gas;the disposition of the constituent atoms may be different (strainedor distorted), although in most cases the difference is but slightand certainly not constitutional.For instance, in naphthaleneeach of the two molecules C1,H, probably resembles very closelyin shape the molecule in the liquid state. Still further, X-rayanalysis has shown clearly that the crystal unit nearly alwayscontains the Substance of more than one molecule, usually two,three, or four. It has also very clearly indicated that the atomsin the unit can be divided into groups, each containing the substanceof one molecule.In the case of organic crystals it has proved to be a very cleardivision into molecules.But in such simple cases as rocksalt anddiamond it is very faint or even indistinguishable. For instance,W. Barlow, Min. Mag., 1895, 11, 119.R. W. G. Wyckoff, “ The Analytical Expression of the Results of theTheory of Space-Groups,” Carnegie Inst. Washington, Publ. No. 318,p. 43the four molecules of NaCl constituting the cry3tal unit of rocksalthave apparently become indistinguishable. Yet there are someilidications “ of association of a sodium atom a t the edge of thecube with a chlorine atom lying along the digonal axis through thesodium. Indeed, in sylvine, KCI, this trace of association is suffi-cient to affect the form of the crystal, giving it the drop in symmetrywhich it actually shows ” (Sir William Bragg in a communicationto the writer just received).With every word of the above, crystallographers can heart,ilyagree, and will be grateful to Sir William Bragg for having sothoroughly cleared the air, and removed the gross misconceptionwhich had arisen, according to which crystals were to be regardedin all cases as merely assemblages of “ ions,” which were confusedwith those of the electrolytic dissociation hypothesis.The sense in which “ ionisation ” is to be understood in connexionwith crystal structure was explained in the last Report (pages 220and 221).It relates only to that one of the two types of chemicalcombination which is characterised by “ electrovalency ” (Lang-muir), the transference of an electron or electrons from an electro-positive atom, having an excess for inert gas stability, to an electro-negative atom deficient in electrons.The other type of combinationis characterised by “ co-valency,” electrons being shared by twoelectronegative atoms to make up their common deficiency ; theatoms are bound more closely together by this co-valent type ofcombination. Even in the case of electrovalent combination,however, where it is due to electrostatic attraction owing to thetwo atoms being left oppositely electrified by the transfer, it hasbeen shown that evidence has been found by Sir William Bragg,notably in the case of potassium chloride, that the moleculesformed retain their identity in the crystal structure.In the caseof co-valency combination, the molecules are obviously very clearlyidentifiable.Sir William recalled that the form of the crystal unit is preciselydefined in absolute measure by X-ray analysis, and is necessarilya parallelepiped, the unit cell of the space-lattice, bounded by threepairs of parallel faces, the distance between a pair, now known asthe “ spacing ” of the plane parallel to the pair, being determinedby the now famous expression : X = 2d. sin 8, where X is the wave-length of the X-rays used, d is the spacing, and 6 is the smallestof the glancing angles which the incident X-rays must make withthe plane in order that reflection may occur. When the spacingof the three pairs of cell-faces is determined, the volume of theunit cell can, of course, at once be calculated.Moreover, the weightof the cell contents is found by multiplying by the density, and th238 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.number of molecules in the unit cell is found by dividing this weightby the weight of the molecule.The shape of the unit has infinite possibilities, for the cornersare all alike in Barlow’s sense, that from each of them the outlookis the same; it is these corners, with all the similar points through-out the crystal, which make up the space-lattice. It comes to thesame thing as regarding the centres of the cells (or any other identi-cally chosen representative point) as the points of the space-lattice.A wide field of research now opens out, the determination of thephysical constants of t,his polymolecular crystal unit: inasmuch asi t possesses all the properties of the crystal.Its elastic, electric,optical, and thermal, indeed all vectorial, properties and constantsnow become of immense importance, and all of them will be intim-ately connected with the detailed internal structure of the crystalunit, that is, with the positions of the atoms composing it, and notimprobably with the distribution of the electrons on the atoms.This detailed structure we can look to X-ray analysis to afford us.It has to be remembered, however, that X-rays cannot distinguishbetween the two sides of a set of reflecting planes. For instance,in zinc blende the two ends of the polar crystal cannot be dis-criminated, although the distance between thc: alternating planes,say those parallel to (lll), of zinc and sulphur is three times asgreat going from zinc to sulphur one way as it is when going theother way.For the intensities of the different orders of X-rayspectra reflected depend on the relative magnitude of the spacingsand not on their order. Similarly, X-rays cannot discriminatebetween a right-handed spiral and a left-handed one, for the oneis the reflection of the other.The number of chemical molecules in the cell (crystal unit)turns out to be intimately connected both with the symmetry ofthe crystal and with that of the molecule. For instance, whilenaphthalene has two molecules in the crystal unit, #-naphthol,in which a hydroxyl group is substituted for one of the hydrogenatoms of naphthalene and which must therefore be less symmetrical,has four molecules to the crystal unit, the symmetry remainingmonoclinic prismatic (holohedral) .Similarly, while two moleculesof benzene go to the crystal unit of benzene, four molecules arepresent in the crystal unit of benzoic acid, the molecule of whichis obviously more unsymmetrical, and in this case the symmetryis also lower. The symmetry of the crystal thus increases with thenumber of molecules in the crystal unit, and also with the symmetryof the molecule itself.The paper of Mr. G. Shearer: already mentioned, was read to the2 G. Shearer, Proc. Physical SOC., 1922CRYSTALLOORAPIIY AND MINERALOGY. 239Physical Society on December Sth, 1922, and the writer is able togive some account of it, as he has been most kindly permitted to seethe proof-sheets.It discusses very fully the number of asymmetricmolecules necessaryper crystal unit to produce the symmetry ofthe 32 classes of crystals. The existence of fewer than this numberof molecules in the crystal unit is shown to imply symmetry in themolecule itself. The relative positions of the variously orientatedmolecules in the lattice are also considered, and it is shown thatonly certain positions are possible. Further, it is concluded thatthe number of molecules in the elementary cell of the space-latticeis always the minimum necessary to satisfy the symmetry conditions,and that any symmetry of the molecule is reproduced in the crystal.Hence, the crystal always shows at least as much symmetry as themolecules which form i t ; indeed, in general, the symmetry of thecrystal is higher than that of the molecule. Shearer's conclusionsare then embodied in the following two rules : (1) The numberobtained by dividing the weight of the crystal unit by the molecularweight is either equal to the symmetry number (the number ofasymmetric molecules in the unit) or is a sub-multiple of it.(2) In thelatter case, the number obtained by dividing the symmet'ry numberby the number of molecule sis the symmetry number of the molecule.Shearer's first rule emphasises the fact that the chemical moleculeis the basis of construction of the crystal unit, and thus lays stillfurther stress on the persistence of the molecule in the solid crystal-line condition.No case has yet been observed in which the numberof molecules is greater than the symmetry number, but cases wherei t is smaller are common. For instance, the great majority oforganic substances examined by X-rays crystallise in the prismatic(holohedral) class of thc monoclinic system, their symmetry numberis four, and four molecules are found in the crystal unit cell. Thisobviously corresponds to molecules having no symmetry, which isvery genera! for organic compounds.The work of Sir William Bragg and his collaborators has shownconclusively that it is possible to obtain decisive evidence of theposition of the individual molecules in a polymolecular crystal unit,and also of the positions of the various atoms making up eachmolecule.Taking this in conjunction with the rules of Shearer, i t is nowfurther possible to obtain a clue to the symmetry of the mole-cule itself.Sir 7;17illiam has laid down two definite principlesconcerning the positions of the molecules in the unit. (a) If acrystal unit contain two molecules, one of which is the reflectionof the other across a plane of symmetry, and each corner of theunit be occupied by a representative of one of the two tgves o240 ANNUAL REPORTS ON THX PROQRESS OF CHEMISTRY.molecule, then the molecule of the other type must lie on a lineperpendicular to the plane of reflection, and passing through thecentre of one of the cell faces. ( b ) If a crystal unit contain two mole-cules, one of which can be brought to coincidence with the otherby a digonal axial rotation (the crystal then possessing a plane ofsymmetry perpendicular to the axis), and if the crystal unit be soFra.1.Oa = 6.44; Ob = &18; Oc = 21.6;B = 97” 6‘.Crystal Unit Cell of Benzoic Acid.placed that each of its cornersis occupied by one of the twotypes of molecule, then themolecules of the other typemust lie on planes perpendicu-lar to the axis and passingthrough a face-centre.Now the “spacing” is thedistance between any planeand the nearest parallel planewhich is identical with theformer as regards its relationto the crystal structure. Andif there are four molecules inthe unit, all four are, ingeneral, differently related toany plane in the crystal.If,for example, the digonal mole-cules of case ( b ) lie in planesinterleaving the planes of theother molecules, the spacingis halved (that of (010) forinstance) ; this occurs in naph-thalene and benzoic acid. If,on the other hand, the digonalmolecules lie in the sameplanes as the original mole-cules, the spacing is notaltered, and this occurs in thetwo naphthols. Thus by thehalving or otherwise of the spacing the positions of the constituentmolecules of a crystal unit can be clearly ascertained. For instance,the positions of the four molecules A , B, 0, D, of benzoic acid,C6H5*C0,H, are shown in Fig. 1. The spacings were determinablewith great accuracy, as very strong reflections of the X-rays wereobtained.The presence of double layers parallel to the (001)plane, and parallel to the very perfect cleavage, is also clearlyshown, and the flakiness of benzoic acid crystals is explained bCRYSTALLOORAPHY AND MINERALOUY. 241the much closer packing of the molecules along this plane than alongthe other principal planes.As regards the kind of conclusions to be drawn concerning thesymmetry of the molecule itself, when the number of moleculesin the crystal unit is less than the symmetry number, the case ofnaphthalene may again be considered as an example. The symmetrynumber is four, but there are only two molecules to the crystalunit; hence, the symmetry number of the molecule is two, that is,i t possesses twofold symmetry and no more, This is strictlydemonstrable only for the crystal molecule (the chemical moleculeas it exists in the crystal), yet there must be some character in thesubstance which disposes its molecule CloHs to take up one or otherof the two mutually digonal forms according to the circumstancesin which it h d s it'self.Moreover, the X-ray results prove that themolecule of naphthalene must have either a plane of symmetry,FIG. 2. FIG. 3.IThe Molecule. The Crystal Unit.The Symmetry of Naphthalene.a centre of symmetry, or a digonal axis. The evidence a t the timeof Sir William's lecture was insufficient to decide which of the threealternatives is correct, but the balance of evidence favoured thecentre of symmetry, the B molecule being both the reflectionand the digonal complement of the A molecule, as illustrated byFigs. 2 and 3, the former representing the symmetry of the moleculeand the latter that of the crystal unit (monoclinic prismatic).In the private communication to the writer already referred to,Sir William states that he has cleared up the doubt, and that thespacing thought at first to be a full one is really halved, and that thereis no doubt whatever that the crystal molecule of naphthalene has acentre of symmetry.In this letter to the writer Sir William Bragg also makes a furtherstatement regarding anthracene, which is important as it opensup a new method, by use of X-rays, of determining the densityof crystallised substances.He has redetermined the spacingswith some excellent little crystals provided by Dr.Brady, and thes242 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.much more accurate measurements show that the c-axis is exactly2.5 longer than in the case of naphthalene, just the right amount tocorrespond to an extra ring. The new numbers are : a = 8.58;b = 6.02 ; c = 11.18 ; p = 125" 0'.The b-axis of naphthalene was found to be 5.98, practicallyidentical with that of anthracene. On working out the densityof anthracene from this new information it is found to be 1.255,and this is probably much nearer the truth than the very approximatevalue, 1.15, given in physical tables. Sir William considers thatas the X-ray methods give the actual (absolute) dimensions of thecrystal structure they afford a means of determining the densityfree from errors of inclusions of various sorts.Some additional X-ray data concerning benzene itself were givenin his lecture by Sir William Bragg.The symmetry number of theFIU. 4. e e(c)Diagrammatic Forms of (a) Benzene, ( b ) Naphthalene, (c) AnthraceneMolecules.crystal is eight, as it belongs to the rhombic bipyramidal (holohedral)class, but there are only two molecules contained in the crystalunit. Each molecule possesses, therefore, fourfold symmetry.But it has neither a trigonal nor a hexagonal axis, and thereforethe conventional method of representing the molecule as a hexagonis not in accordance with fact. The correct arrangement is slightlydifferent from the sixfold arrangement of carbon atoms in the dia-mond, and it is shown in perspective in Fig.4, which also showsa t (b) the arrangement in naphthalene and a t (c) that in anthracene.The figure of benzene a t (a) has the correct amount of symmetryfor the molecule of benzene as it occurs in the crystal; i t is morein accordance with the Dewar or Ladenburg formula than with thatof Kekulh or of Claus. It will be remembered that the formulaof Dewar is that here shown, the suffix after the C representing theorder of the carbon atom and not the number of atomsCRYSTALLOGRAPHY AND MINERALOGY. 243It probably possesses a plane of symmetry and an axis of symmetryperpendicular to it, but this is not trigonal. The figure for the two-ringed molecule of naphthalene a t ( b ) has a centre of symmetryonly, which has just been shown to be the fact.That a t ( c ) foranthracenc has a third ring of the diamond form inserted betweenFIQ. 6 . FIU. 6.aThe Crystal Molecule of Al,O,,showing arrangement of Atoms.Section through Centre ofMolecule, showing arrange-ment of Electrons in theOxygen Atoms.those of naphthalene. The sides of all the hexagons are equal,but do not lie in a plane, and the angle between any pair of adjacentsides is the tetrahedral angle 109" 28'.As a couple of final examples of the truth of Shearer's rules,the simpler inorganic cases of quartz and corundum may be referredto. The quartz crystal is of sixfold symmetry, and a.s its crystalunit contains three molecules of SiO,, spirally arranged in accordancewith trigonal (class 18) symmetry, each molecule has twofold sym-metry only.The crystal possesses digonal axes, hence the moleculeof SiO, has digonal symmetry. Corundum has twelvefold (trigonalclass 21) symmetry, with a crystal unit comprising two moleculesof Al,O,, the axial ratio being a: c = 1 : 2.73 and not 1 : 1.365as usua,lly given. The molecule, therefore, possesses sixfold syni244 ANNUAL REPORTS ON THE PROGRESS OF CHEMLSTRY.metry. X-Ray determinations with the ruby indicate the structureshown in Fig. 6, which agrees with trigonal symmetry, but does notshow the nature of the additional twofold symmetry. In Fig. 6,which shows a section of the molecule, the digonal axis is, however,clearly visible at m. Thus the molecule contributes the trigonaland digonal axes, while the crystal structure contributes the planesof symmetry which are characteristic of class 21, for the moleculeitself has no plane of symmetry.Sir William Bragg and Mr.Shearer both suggest that, as indicated in Fig. 6, the distributionof the six electrons in the outer shell of the oxygen atoms is suchas determines that the crystal shall have the three symmetry planes,in addition to the symmetry elements already present in the molc-cule owing to the positions of the atoms.There has thus been accumulated a mass of evidence that therules enunciated by Shearer are truly valid. The case of tartaricacid is another contributing weighty evidence in the same direction,but this is an altogether remarkable and exceptionally interestingcase and will be dealt with in a separate section.Before passingto this, however, reference may be made to an important questionraised by Shearer : What determines the choice by any substanceof the peculiar form characteristic of itself? For if the moleculebe asymmetric all the 32 classes are open to i t to crystallise in.But it is very improbable that it will choose the class 32 of highestcubic symmetry, for 48 molecules would then be required to formthe crystal unit, whereas 8 molecules is about the maximum numberyet found in any space-lattice cell, and this is very exceptional.Asymmetric molecules will therefore crystallise in classes of lowsymmetry, which is, indeed, found to be the case. Out of a thousandorganic aromatic compounds passed in review 60 per cent.requireonly four molecules to the crystal unit. If, however, the moleculepossess some symmetry, its choice will fall on a higher class of sym-metry, the higher the greater the symmetry of the molecule.The Structure of Tartaric Acid.The coincidence is a most happy one, that the structure of tar-taric acid has been successfully determined by Mr. W. T. AstburyY5 inSir William Bragg’s laboratory, a t the very time of the Pasteurcentenary.In the paper read to the Royal Society on December 7th, 1922,presenting the results of the X-ray spectrometric analysis, notonly are the conclusions of Pasteur confirmed in absolute measure,but some of the more obscure of the properties of this exceptionallyinteresting and important substance are cleared up by the nature ofii PTOC.Roy. SOC., 1922, [ACRYSTALLOGRAPHY AND NINERALOGY. 245the structure which is revealed. The crystal structure of ordinarytartaric acid proves to exhibit just such a, spiral arrangementof the four carbon atoms of the molecule as was assumed from thecrystallographic, enantiomorphous, character of the crystals andfrom their dextrorotatory power. The theory of stereoisomerismof Le Be1 and van't Hoff is in its essentials confirmed, and the directlink between the crystallographic enantiomorphs and the chemicalstereoisomerides is revealed. But it is shown to be impossible todistinguish between the dextro- and Izevo-forms of such an opticallyactive enantiomorphous substance. The structure established,however, affords a simple explanation of the anomalous rotatorydispersion, involving a maximum for a specific wave-length of light:which is exhibited both by tartaric acid and by its derivatives.The Bragg ionisation-spectrometer and a Coolidge bulb withmolybdenum anticathode were employed, the crystals used beingFIU.7. FIG. 8.dextro-Tartaric Acid. lzevo-Tartaric Acid.those of ordinary (dextro) tartaric acid, c4&06. The crystalsbelong to the sphenoidal class 4 of the monoclinic system, and theirconstants are a : b : c = 1.2747 : 1 : 1.0266; p = 100" 17'; density1.759. The next two figures (Figs. 7 and 8) represent two typicalcrystals of the dextro- and laevo-varieties of tartaric acid, whichdiffer essentially by the dextro-crystal exhibiting only the rightclino-prism (01 1) and the lzevo-crystal only the left clino-prism (01 1 >.The crystal unit is found to contain two molecules C4H60,, andas the symmetry number is two, each molecule must be asymmetricin accordance with Shearer's rule, and with the absolutely essentialcondition for optical activity, the absence of second-order symmetryelements, symmetry planes being certainly absent.The crystalalso being likewise optically active, must be without any plane ofsymmetry, and must possess some kind of spiral structure, whichis right-handed in one of the active varieties and left-handed inthe other.The structure which Mr. Astbury eventually deduces from hi246 ANNUAL REPORTS ON THE PROGRESS OB CHEMISTRY.X-ray spectrometric measurements of spacings and intensities ofthe various spectral orders, together with the known crystallo-graphic and density data above given, is shown in Fig.9. Theportion of the figure marked I shows the crystal unit of tartaricacid and the arrangement of the molecules. Of the two moleculesforming each crystal unit one is the digonal complement of theother, and the spacing of the (010) planes is found to be halved inconsequence. Moreover, the structure exhibits not only one spiralbut two spirals, differently handed but not mirror-image comple-ments and occurring in different parts of the structure. One isassociated with the four carbon atoms at the centre of the moleculeThe Structure of Tartaric Acid.and forming its nucleus, and thc other with the four hydroxylgroups.To the former spiral is due the optical activity of thesolution, for it is permanent, persisting in the molecule itself;whereas the latter spiral appears only in the crystal structure anddisappears in solution. Its rotation effect on the plane of polarisa-tion of light is greater than that in the opposite direction due tothe first screw, and so determines the sign of rotation of the tartaricacid crystal, which appears to be the opposite of that of the solution.Parts II(a) and II(b) show the two enantiomorphous forms ofthe crystal unit, and the arrangement of the two molecules alongthe axis a, as well as the projection of the carbon core on a planeperpendicular to axis a.Part I11 shows the section of the crystalunit perpendicular to axis a, with the arrangement of the moleculCRYSTALLOGRAPHY AND MINERALOGY. 247at each corner and its digonal complementary molecule a t thecentre.This structure agrees with all the purely crystallographic dataconcerning tartaric acid. The two forms shown a t II(a) and II(b)are clearly enantiomorphous with respect to each other. It alsoexplains the one perfect cleavage parallel (loo), the plane aboutwhich lie the junctions of the hydroxyl groups. For the moleculesare held together end to end by forces between the hydrogen atomsof adjacent hydroxyl groups, one OH group being carboxylic andthe other alcoholic. None of the strong valency forces acts acrossthis plane (loo), but only these weaker forces acting from moleculeto molecule and serving to bind them together in the crystal lattice ;hence, it is pre-eminently a plane of possible cleavage, as is actuallyobserved. The junctions in the (=OH-) linkages are stronger,hence, there is no cleavage across them, doubtless due to the oxygenhaving double linkage. The distance between carbon and oxygenatoms in the (-GO) groups is also less than in the (-C-O-H)groups, and this is doubtless due to electron-sharing.Another interesting fact is that there is a particularly intensefirst-order reflection of the X-rays from the (011) plane, and it isprecisely this plane which has the greatest density of atoms perunit area; the interleaving also throws most of the energy into thefirst-order spectrum from this plane. Now the crystals themselvesusually develop these planes characteristically, (01 1) on right-handed crystals and (011) on left-handed ones, as shown in Figs.7 and 8.This agrees with the well-known crystallographic principlethat a crystal tends to develop best the planes of greatest reticulardensity.The spiral nature of the two enantiomorphous structures showna t IUa) and II(b) will be obvious, and the fact that they are ofopposite winding. The four carbon atoms which form the nucleusof the molecule are situated a t alternate corners of the obliqueparallelepiped, and this automatically produces an irregular spiralformation within the molecule itself. Moreover, the hydroxylgroups are arranged in another spiral of opposite kind, the junctionbetween the hydrogen atoms being only possible when this is so,this second twist reversing, and more, the twist of the nucleus ofthe molecule just described. Each of these twists in one enantio-morph is the opposite of that in the other, and this reversal of twistinverts the order of succession of the (-H), (-OH), and (-CO*OH)groups round the asymmetric carbon atoms.The structure agrees with the fact that the plane of the opticaxes of tartaric acid is perpendicular to the one symmetry plane ofthe monoclinic crystal, the obtuse bisectrix coinciding with th248 ANNUAL REPORTS ON THE PROGRESS OF CHXMISTBY.unique digonal symmetry axis b, so that the two optic axes makeequal angles with axis h ; it consequently also agrees with the factthat the rotatory power along each of the two optic axes is the same,namely, according to Dufet 8" 33' per millimetre of thickness ofplate for red lithium light, increasing with shortening wave-lengtht o 14" 14' for green thallium light.The unusual property mas discovered by Biot, that solutions oftartaric acid in water or alcohol show a maximum rotation in thegreen, and also that the specific rotation of an aqueous solutiona t a given temperature is a linear function of the concentration :[a] = A + BE, where E is the proportion of water in the solution.By extrapolation he also obtained the rotation of the anhydrousacid, and predicted that for red light this would change sign a t 23".This prediction was subsequently verified.Now these remarkablefacts are also explained by the structure of the crystals as now revealedby X-rays, the two opposite rotatory systems produced by thetwo opposite spiral twists of the two parts of each molecule beingadequate to account for them completely. The involved explana-tion suggested by Lowry is thus unnecessary, the structure aloneaffording a sufficient cause.The final conclusion is that the dextrorotatory power of ordinarytartaric acid is t o be ascribed solely to the presence within themolecule of a system of four carbon atoms forming an irregularspiral. The direction of twist of this spiral is the opposite of whatit is in Zcevo-tartaric acid. Arguing from the analogy of Reusch'spile of mica plates simulating quartz and its rotation, a clockwisespiral of atoms will produce dextrorotation (meaning that the planeof polarisation of light is rotated to the right or to the left from thepoint of view of a person looking into the microscope), and an anti-clockwise spiral lsvorotation.In dextro-tartaric acid the orderof sequence of the (-H), (-OH), and (-CO*OH) groups is anti-clockwise, as we look towards the asymmetric carbon atom in thedirection leading towards it from its companion asymmetric carbonatom. The aspect of the molecule as a whole shows a distortedtetrahedral arrangement of bonds.It would thus appear that the structure arrived a t as the resultof this interesting investigation explains in a most satisfactoryfashion even the smallest details of the physical properties, in manyways peculiar and unusual, of tartaric acid, as well as confirmingthe general conclusions of Pasteur and later workers as to theessential characters of the two varieties and their relations to theoptical activity of this typical enantiomorphous substance, the firstof the large class of such substances which have since become knownCRYSTALLOGRAPHY AND MINERALOGY.249Further Light on Functions of Exterior Electrons.It was shown in the last Report that some light had been thrownon the situation of the outer electrons of the atoms by some specialexperiments, concerning the intensity of certain orders of X-rayreflection from the planes of atoms in the diamond and fluorspar,by Sir W. H. Bragg and M i .H. Pealing. It is immaterial, as regardsthe symmetry of the atoms, whether the electrons are stationaryor moving in orbits, so long as in the latter case the distributionof the orbits or of their normals is considered. In any case, theouter electrons are prime factors in the problem of atomic symmetry,and the concluding portion of Shearer’s paper deals with thisaspect of the subject. Now a considerable number of the elementscrystallise in the highest class 32 of cubic symmetry, .while thecrystal unit only contains two or four atoms.If we consult Shearer’s table giving the number of asymmetricmolecules required to build up the crystal unit in each o€ the 32classes (this number varies from 1 in class 1 to 48 in class 32),and divide the 48 there given as corresponding to class 32 by 2 or4, we arrive at 24-fold or 12-fold symmetry as being that possessedby these elementary atoms, and this corresponds to one of the lowerclasses of the cubic system.Prom this Shearer concludes that thereis some form of cubic arrangement of the electrons or their orbitsin these atoms. Carbon, in the diamond form, even if consideredas only belonging to class 31 (whereas there is more evidence thatit really belongs to class 32), as it has eight atoms to the crystalunit, would have the symmetry number three, and would thereforepossess a trigonal axis. Hull’s structure for graphite also supportsthe assumption that the carbon atom possesses a trigonal axis ofsymmetry in its structure. It would thus appear that for crystallo-graphic purposes what matters is the outer electronic arrangement,and not the atomic nucleus.In the last Report it was also shown that a formula for the intensityof reflection from a crystal plane of atoms had been arrived a tby W.L. Bragg, R. W. James, and C. H. Bosanquet, embodyingalso some important results of C. G. Darwin and A. H. Compton,and also those of P. Debye and P. Scherrer, in which occurred animportant factor, P, which depended on the number and arrange-ment of the electrons of the diffracting atoms constituting theplane. C. G. Darwin,6 however, has since shown that on accountof the difficulty in determining the effective coefficient of extinctionof the X-rays the result affprded by the formula is not quiteaccurate, and has suggested a’ new formula, based on his experi-ments with powdered crystals, as affording more accurately theC.G. Darwin, Phil. Mag., 1922, [vi], 43, 800; A., ii, 416250 ANNUAL REPORTS ON THE PROGRESS OE" CHEMISTRY.amplitude of the wave scattered by all the electrons in a singleatom in the direction of the reflected beam. A. H. Compton andN. L. Freeman have also arrived at the same conclusion, and havemade quantitative measurements of the intensity of X-rays derivedby reflection from rocksalt and then scattered by powdered crystalsof sodium chloride, using the K, line from molybdenum (A = 0.708B.U.). They found that the theory of X-ray reflection which hasbeen put forward by Sir W. H. Bragg then gives accurate results.In a further paper, W.L. Bragg, James, and Bosanquet revise theirresults in the light of these contemporary researches, and havereduced the error due to the extinction uncertainty to a minimum.The results then indicate that neither in the sodium nor the chlorineatom can there be eight electrons in an outer shell, or eight electronsdescribing orbits lying on an outer sphere; but that a combinationof circular and ellipitic orbits would agree with the P curves as nowcorrected. This would appear to indicate that the theories of Bohrand of Langmuir concerning atomic structure are neither alonecorrect, and that the truth lies somewhere between the two, a con-clusion which has lately been emphasised from all sides.Effect of Temperature on X-Ray Rejlection.This has been studied during the year by I.Backhurst in SirW. H. Bragg's laboratory. According to C. G. Darwin and to P.Debye the intensity diminishes as the temperature of the crystalincreases, and it does so more rapidly as the angle of reflectionincreases. These conclusions were supported by experimentsmade some time ago by Sir William Bragg, and are now fully con-firmed by Mr. Backhurst's results.9 Sir W. H. Bragg's apparatuswas used, the crystal being placed in an electric heater furnished withmica windows for ingress and egress of the X-rays, the thermometerbulb being immediately over the crystal. Sir W. H. Bragg'soriginal apparatus only permitted of determinations with rocksaltand sylvine up to 370" and 311", respectively, but in the newarrangement a much higher temperature can be maintained, andthe crystal be environed by an atmosphere of nitrogen, a thermo-couple being substituted for the thermometer at the higher tempera-tures.Crystals of aluminium, carborundum, graphite, diamond,sapphire, and ruby were studied. Aluminium showed a verymarked decrease of reflection intensity with rise of temperature, infair agreement with Debye's theory. Carborundum proved stableenough to be tested (using a special furnace) up to as high a tempera-7 A. H. Compton and N. L. Freeman, Nature, 1922,110,38.8 W. L. Bragg, R. W. James, and C. H. Bosanquet, Phil. Mug., 1922, [vi],@ I. Backhurst, Proc. Roy. Soc., 1922, [ A ] , 102, 340.44. 433 : A . , ii, 703CRYSTALLOGRAPHY AND MINERALOGY, 251ture as 960°, and gave much greater decreases of intensity for thehigher spectral orders.Graphite, studied up to 850”, agreed withtheory, but also showed an unusually high coefficient of expansionperpendicular to (0001 ), which further emphasises the weaknessof the bonds in this direction referred to in the last report. Diamondwas remarkable as showing practically no decrease of intensity,owing to its great strength and the slight degree of thermal agitationwhich i t evinces. Ruby and sapphire showed an anomalous effect,indicating that the pair of aluminium atoms remain in contactand do not share in the expansion of the lattice which is observed.Crystal Structure CGS determined by X-Rays and the 230 Space-groups.A fact which has become more and more emphasised during theyear is that all the results of X-ray analysis of crystals which areopen to no ambiguity have shown that the crystal structure con-forms to one or other of the 230 types of homogeneous structurewhich Schoenflies, Fedorov, and Barlow united in specifying asthose alone possible to crystals.The facts are concisely expressedas follows : ‘‘ Direct experimental proof is afforded that the struc-tural units, the component chemical atoms and their molecularor polymolecular groups, are arranged in crystals in one or otherof the 14 space-lattices as regards the main grosser structure (thatof points representative of the molecule or small group of molecules),and in one or other of the 230 point-systems as regards the ultimateunits, the chemical atoms themselves.. . . Indeed, it must happenthat the structure revealed by X-rays shall agree with one of the230 types of homogeneous structures which alone are possibleto crystals.,’ These words, quoted from the second edition of thewriter’s book10 published early in the year, page 705 of Vol. I,are thus now by the year’s work more than ever confirmed.It is consequently of the highest importance for workers in theX-ray field of research to have before them a clear presentmentof the 230 types. They are only in the simpler cases hard-and-faststereotypes ; for the great majority permit of considerable varietyin the details of the arrangement of the ultimate units (atoms),and it is the quite feasible task of the X-ray investigation to discoverthese details.The 65 (of the 230) more fundamental point-systems ofSohncke, to which or to their special cases most of the structuresyet elucidated correspond (some of these special cases being simplespace-lattices themselves) , involve only coincidence movementsor symmetry elements of the first order (rotations about axes,possibly screw axes, and translations), the other more rarely natur-10 A. E. H Tutton, ‘‘ Crystallography and Practical Crystal Measurement.”Second edition in two volumes, Macmillan & Co., 1922252 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ally occurring 165 types involving also operations and symmetryelements of the second order (symmetry planes, mirror-image-reflection planes, mirror-axes, inversions, or symmetry centres).The 65 Sohncke point-systems are all described and illust>rated,with exact reproductions of Sohncke’s drawings, in the writer’sbook just referred to, pages 601 to 621.The special cases are alsodescribed in which the point-system becomes reduced directlyto one of the 14 space-lattices of Bravais, and the derivation ofthe other 165 point-systems from the 65 is traced, and a table givenshowing the distribution of the whole 230 among the 32 crystalclasses and seven crystal systems, with the Schoenflica class symbolsand his space-group numbers. The details of the symmetry ofall the 230 space-groups have been given by all three of the originalindependent discoverers, but the notation of Schoenflies, as givenin his “ Krystallsysteme und Krystallstructur,” published in Leipzigin 1891, has become more generally adopted.An excellent summaryof i t is given by H. Hilton in his “ Mathematical Crystallography,”published in Oxford in 1903. P. Niggli has more recently, in his“ Geometrische Krystallographie des Discontinuums ” (Leipzig,1919), given a considerable number of special cases of the space-groups, and has specified the positions within the unit cell of eachspace-group of all its symmetry elements.H. Hilton, in a paper l1 to the Mineralogical Society in June last,refers to the bewildering variety of other suggested notations thanthat of Schoenffies, and points out that the Schoenflies notationitself suffers from two serious drawbacks.The first is that rotationand rotatory reflection are taken as fundamental operations, whereasfor crystal-structure purposes rotation and rotatory inversionare needed. The second is that it is troublesome and expensiveto print, involving small index and suffix numbers or letters afterthe capital Ietter symbol. He therefore suggests yet anothernotation, involving only English type and nothing above or belowthe line.In October last a memoir of 180 pages in book form by R. W. G .Wyckoff 4 was published by the Carnegie Institute of Washington,in which all the special cases of the space-groups have been workedout. The matter contained is largely tabular, giving the co-ordinates of the most generally placed equivalent points and allthe special cases of these equivalent points, contained within theunit of structure of each of the 230 space-groups.In this form theinformation will be immediately available to X-ray analysts.For a review of all the X-ray analyses yet carried out has shownthat the number of particles (atoms) contained in the unit cell is11 H. Hilton, Min. Mag., 1922, 19, 319ORYSTALLOGRAPEY AND MINERALOGY. 253usually smaller than the number of most generally placed equivalentpoints of the apace-group having the symmetry of the crystal.The special arrangements of the equivalent points (on axes, planes,or other symmetry elements), whereby the number of symmetryelements is reduced, are thus of great importance to the X-rayanalyst. This book is, therefore, one of very considerable value.Iteference has, however, been already made to one pointwhich it would be a clear advantage to remedy in any futureedition of the work, namely, the replacement of the term " crystalmolecule " by '' crystal unit," which is really what Wyckoff meansby the term.As Sir William Bragg remarks in a letter to the writer,the term " crystal molecule " is much better left to indicate thechemical molecule as it exists in the crystal unit, which latter isusually, as already so clearly proved, composed of more than onechemical molecule. FOP it ia, indeed, most essential to discriminatebetween three very different things, the crystal unit, the crystalmolecule, and the chemical molecule. By the latter is to be under-stood the molecule as it exists in the gaseous or liquid condition.Miscellaneous X-Ray Results.An important paper by M.Siegbahn,12 on the improvementswhich he has introduced into X-ray spectrometry, g' ives someremarkably accurate determinations, suitable for use as Standardsof Reference, of the angle of reflection of the first-order K, radiationof copper from calcite. They are as follows :With crystal fwe polished.14O 4%' 2.8"14 41 69.814 41 69.614 42 1-314 41 69.514 42 2.3With rough cleavage face.14' 42' 0.0''14 41 59-914 41 69.214 41 58-014 41 69.614 42 5.5____~ ~Mean 14' 42' 0-8" Mean 14' 42' 0.4"The difference for the two conditions of face being so minute,the h a 1 mean 14' 42' 0.6'' may be taken as a standard value.We have here an excellent proof that it is the inner planes withinthe crystal substance that are chiefly concerned in contributing t othe reflection, and not the surface of the crystal face.A Ntdi$cation of the Powder Method was described by E.A. Owenand G. D. Preston to the Physical Society on December 8th, 1922,in which plates of aluminium, iron, copper, lead, and magnesiumwere examined on the Bragg X-ray spectrometer, employingradiation direct from a molybdenum anticathode. Excellentl2 Cornpt. Tend., 1921, 178, 1350; A., ii, 104254 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.spectra were obtained, which enabled the structure of these metalsto be readily determined. Sir William Bragg pointed out thatone of the planes becomes unduly accentuated by the polishingprocess, and this has to be remembered in interpreting the results.'The Xtructureof Ice.-In the last Report theworkof D.M. Dennisonwas recorded, who found ice to have the structure of a close-packedhexagonal lattice, composed of two sets of interpenetrating triangularprisms, with edges 4-52 and height 7.32 B.U., the axial ratio beinga : c = 1 : 1.62. Sir William Bragg,13 revising this work and theearlier work of A. St. +John, finds that four such lattices interpene-Fra. 10.W4.5ZAUThe Structure of Ice.trate to form the comp3ete structure, and confirms Dennison'sfigures for the dimensions. Each oxygen atom is at the centreof gravity of four neighbouring equidistant oxygen atoms, fromeach of which i t is separated by a hydrogen atom, there being twiceas many hydrogen atoms round each oxygen atom as there are oxygenatoms round each hydrogen atom. I The structure is shown in Fig.10.The structure is an extremely open one, corresponding to the lowdensity 0.9165, and i t is easy to suppose that loose H,O molecules,liquid water, would occupy less space, so that the expansion onfreezing, and the melting of ice by pressure, is accounted for. Thedimensions of the hydrogen atom are here measured for the firsttime, the sum of the diameters of oxygen and hydrogen atoms being2.76 A.U. As the diameter of the oxygen atom is 1.30, that ofProc. Phy8. &C., 1922, 34, 98CRYSTALLOGRAPHY AND MINERALOGY. 255hydrogen will be 1.46 d.U. This is not too large, for G. Aminoff l4has calculated it from investigations of magnesium and manganesehydrides as 2.16, and from the structure of ice as 2.24.From itsrelation to the alkali metals hydrogen might well be expected tohave this slightly larger diameter than oxygen.Structure of the Crystallised Elements.-A. W. Hull15 has pub-lished two papers since the last report, regarding further resultswith his powder method. Summarising, cobalt, nickel, rhodium,palladium, iridium, platinum, and thorium have the face-centredcube structure. Iron has the centred cube structure. Rutheniumand osmium have hexagonal close-packed structures, the axialratio of each being 1-59. Titanium, zirconium, and cerium havedistorted hexagonal close-packed structures, with axial ratios 1-59in the first two cases and 1.62 in the case of cerium.L.W. McKeehanls haa determined the structure of potassiumcooled to -NO", and found the atoms to be arranged on a centred-cube lattice, with a = 5.20 &U, The observed crystalline structuredoes not persist as the metal is allowed to regain room temperature.He has also investigated crystallised glucinum and found that itresembles magnesium, zinc, and cadmium (close-packed hexagonal)rather than calcium, strontium, and barium. There are two sym-metrically interpenetrating hexagonal space-lattices, the sidebeing 2.283 A.U.The crystal structure of germanium has been determined by N. H.Kolkmeyer l7 by the powder method, and found to resemble thatof diamond, and the similar forms of silicon and tin.The latticeparaqeter a = 5-61 B.U.Iron in its various forms has been studied by A. Westgren and A.E. Lindh,l8 and also by Westgren and G. Phragmen.19 For pureiron (or-iron) Hull's result is confirmed, namely, a centred-cubelattice. Between 800" and 836", within the B-iron region, the atomicgrouping remains the same. They regard allotropy and poly-morphism as synonymous, and that @-iron is only a particularmodification of a-iron. Austenite and pure iron a t 1000" were foundto have a face-centred cube lattice, which is also characteristicof y-iron. Hence the two really different forms are a- and y-iron.Martensite was found to be a-iron, as was also high-speed tool steelG. Aminoff, cfeol. Fdr. FGrh., 1921, 43, 389; A., ii, 496.A.W. Hull, Phy8iCal Rev., 1921,18,88; J. FranMin Inst., 1922,193,189;seo also A., ii, 624.l6 L. W. McKeehan, Proc. Nat. Acad. Sci., 1922, 8, 254, 270; A., ii, 709.l7 N. H. Kolkmeyer, PTOC. K . Akad. Weten8Ch. Arneterdam, 1922,25, 125 ;l8 A. Westgrenand A. E. Lindh, 2. phY8ikal. Chem., 1921,98,181; A., ii, 152.A . , ii, 713.A. Westgren and G. Phragmen, a i d . , 1922, 102, 1 ; A., ii, 711256 ANNUAL REPORTS ON THB PROGRESS OF CHE~MISTRY.hardened a t 1275'. Iron wire at 800", 1100", and 1425", withinthe p and y regions, has the centred-cube structure like a-iron.The transition which occurs a t 900" (A3) is reversed a t 1400" (A4).The presence of carbon extends the space-lattices. Cementiteand spiegeleisen crystals were found to be identical, of rhombicsymmetry with four molecules of Fe&! to the crystal unit,Lithium Hydride has been studied by J.M. Bijvoet and A. Kars-sen,2o and found to be cubic with four molecules of LiH to thecrystal unit, the side of which is a = 4.10 d.U., the structureresembling that of rocksalt.Silver Oxide, which crystallises in small octahedra, has beeninvestigated by the powder method by R. W. G. Wyckoff,21 andfound to resemble cuprous oxide, with a unit cube containing twomolecules of Ag20, and an edge of 4.768 B.U.Magnesium Oxide has been reinvestigated by W. Gerlach and 0.PauliZ2 by the powder method, and found to be constructed on aface-centred cube lattice, with length of side 4.22 A.U., identicalwith the previous value.Glucinum Oxide has been investigated by L.W. McKeehan,22a whofinds the diffracting centres to lie at the points of two symmetricallyinterpenetrating hexagonal space-lattices having the side 2.696 B.U.Alkali HaZides.-Ammonium chloride has been studied by R. W.G . Wyckoff 23 by the spectrometric and powder methods (firstpaper) and by the Laue radiographic method (second paper), andhe has decided for tetrahedral and not plagihedral symmetry,the unit cube having only one molecule contained in it. Thechlorine atoms are situated at the cube corners, the nitrogen atomat the cube centre, and the four hydrogen atoms are arrangedtetrahedrally arouqd and near the nitrogen atom. The side of theunit cube is 3-859 A.U.E"or this work some excellent crystals, clear rectangular prismsseveral millimetres in size, were obtained, from solutions containingurea.They afforded a refractive index of 1.639, and gaveexcellent Laue radiograms.Lithium chloride, bromide, and iodide, and sodium, potassium,rubidium, and caesium fluorides have been investigated by E.Posnjak and R. W. G. Wyckoff,24 and the results, together with20 J. M. Bijvoet and A. Kamsen, Proc. K. A h d . Wetenech. Amsterdam,1922, 26, 26 ; A., ii, 56%21 R. W. G. Wyckoff, Amer. J. Sci., 1922, [v], 3, 184; A,, ii, 291.22 W. Gerlach and 0. Pauli, 2. Phyaib, 1921, [vii], 2, 116.220 L. W. McKeehan, Proc. Nat. Acad. Sci., 1922,8, 254,270; A., ii, 700.23 R. W. G. Wyckoff, Amer. J. Sci., 1922, [v], 3, 177; 4, 469; A., ii, 290.24 E. Posnjak and R. W. G. Wyokoff, J.Wa~?bin$un A d . Sci., 1922,12, 248; A., ii, 499CRYSTALLOGRAPHY AND MINERALOGY. 257those of former work, are tabulated for twenty salts of the type RX.All prove to be of rocksalt type with simple cubic lattice, exceptcasium chloride, bromide, and iodide, which possess the centred-cube lattice structure.In the writer’s opinion, this difference of structure on the partof the caesium halides at once explains why a clear progression incrystallographic constants and properties is not manifested by thepotassium, rubidium, and caesium salts of halogen acids, similarto that which characterises the sulphates. The caesium halidesare obviously not strictly comparable with the correspondingpotassium and rubidium halides.W. P. Davey and Miss F.G. Wick25 also find caesium chlorideto be constructed on a cubic lattice, with caesium atoms a t thecorners and a chlorine atom at the centre of each cube. Thespacings for the cube planes are for KCl6.26 (Bragg), for RbCl 6.60(Wyckoff), and for CsCl 4.12 b.U. (Davey and Wick), the latterbody-centred cube value being thus quite different from the valuesfor the former two rocksalt groupings.Cuprous Chloride, Bromide, and Iodide have been studied by R. W.G. Wyckoff 26 and prove to have the zinc blende arrangementof atoms in their crystals, the lengths of the sides of the unit cubesbeing respectively 5.49, 5.82, and 6.10 B.U.Potassium Cyanide has been examined by R. M. B ~ z o r t h , ~ ~ usingall three methods (of Laue, Bragg, and Debye).A structuresomewhat similar to that of rocksalt is indicated, with potassiumatoms a t the sodium positions and the carbon and nitrogen atomsnear the chlorine atomic positions, and 1.15 B.U. apart, equi-distant in each case from the chlorine position in rocksalt.Cadmium’ Iodide has also been examined by Bozorth2’a andfound to be trigonal and not, as supposed, hexagonal. The crystalunit contains one molecule CdI,, and the shortest distance betweenthe centres of the cadmium and iodine atoms is 3.00 A.U., whichis exactly the sum of the radii given by W, L. Bragg.The Aragonite Group of Jfinerals (aragonite, strontianite, witherite,and cerussite) forms the subject of a paper by M. L. Huggins,28who suggests that each carbon atom, as in calcite, is linked by doublebonds to three oxygen atoms, each oxygen atom to two calciumatoms and one carbon atom, and each calcium atom to six oxygen86 W.P. Davey and Miss F. G. Wick, Physical Rev., 1921,17, 403.26 R. W. G. Wyckoff and E. Posnjak, J . Amer. Chem. Soc., 1922,44, 30;27 R. M. Bozorth, ibid., 317; A., i, 441.a m Ibid., 2232; A., ii, 857.28 M. L. Huggins, Physical Rev., 1922, 19, 354; A., ii, 463.A., ii, 295.REP.-VOL. XIX. 258 ANNUAL REPORTS ON THE PROURESS OF CHEMISTRY.atoms, a t the corners of an irregular octahedron (presumably arhombic pyramid).The Group of Isornorphous Nitrates of lead, barium, strontium,and calcium, R(N03),, crystallising in the tetrahedral pentagonaldodecahedra1 class 28 of the cubic system, has been studied by L.Vegard 29 by the powder method.The metallic atoms are arrangedin a face-centred lattice ; three oxygen atoms and one nitrogen atomform a group at four of the corners of a cube, this group having atrigonal axis and being surrounded by four metallic atoms.Sodium Chlorate and Bromate, which also crystallise with class 28symmetry, have been reinvestigeted by R. G. Dickinson and E. A.G o o d h ~ e . ~ ~ The atoms appear to be arranged with the symmetryof the Schoenflies space-group T4, all the oxygen atoms beingequivalent.Phosphonium Iodide, PH,I, has been submitted by R. G. Dickin-son31 to both the Bragg and Laue methods of X-ray analysis,and found to afford a similar structure to ammonium chloride atlow temperatures. The unit cell has the dimensions 6.34 by 6.34and 4.62 B.U.Ammonium Chloropkatinate, (NH,),PtCl,, has been examined bythe Laue method by R.W. G. Wyckoff and E. PosnjakF2 and appearsto have a structure resembling that of fluorspar, in which the PtCl,groups replace the calcium atoms, and the ammonium groupsreplace the fluorine atoms. The crystal unit cubic cell has a sideof 9.843 B.U. Curiously enough, Wyckoff 33 also finds that thecrystals of the complex nickel ammonia compounds of the typeNiX,,GNHs, formed when ammonia is added to solutions of nickelchloride, bromide, and iodide respectively, are arranged in a similarmanner isomorphous with ammonium chloroplatinate, the sidesof the unit cells in the three cases being 10*09,10.48, and 11.01 Q.U.I n each case there are four molecules in the crystal unit cell, thenickel atoms replacing those of platinum, and the nitrogen atomsoccupying the positions of the chlorine atoms.Potassium Chloroplatinate, K,[PtCI,], and the salts Rb,[PdBr,]and [Ni(CH3),]C1, have also been investigated by P.Scherrer andP. Stoll 34 and found to resemble fluorspar and ammonium chloro-platinate, the co-ordinated complex in square brackets replacingthe calcium.29 L. Vegard, Z. Physik, 1922, 9, 395; A., ii, 503.30 R. G. Dickinson and E. A. Goodhue, J. Amer. Chent. SOC., 1921,43,2045 ;31 R. G. Dickinson, ibid., 1922, 44, 1489; A., ii, 640.82 R. W. G. Wyckoff and E. Posnjak, ibid., 1921,43, 2292; A., ii, 214.33 R. W. G. Wyckoff, ibid., 1922, 44, 1239; A . , ii, 573.s4 P.Scherrer and P. Stoll, 2. anorg. Chem., 1922,121,319; A., ii, 524.A., ii, 145CRYSTALLOGFLAPHY AND MINERALOGY. 259Ammonium Pluosilicate has been structurally analysed by X-raysby R. M. B ~ z o r t h , ~ ~ and found also to resemble ammonium chloro-platinate, ainnionium chlorostannate, and potassium chloro-stannate, namely, in possessing fhe type of structure of fluorspar,the fluorine atoms of the latter being replaced by an ammoniumgroup, and each calcium atom by a fluosilicate group, with the sixfluorine atoms equidistant from the silicon atom in the directionof the crystal axis. The unit cube contains four molecules of(NH,),SiF, and the side measures 8.38 A.U. The sides of the otherthree compounds mentioned are respectively 9.84, 10.05, and 9.96Silver Molybdate has been examined by R.W. G. Wyckoff 3Gby both the X-ray spectrometric and the radiographic methods,and found to possess a structure like that of magnetite and thespinels, with eight molecules to the unit cube, which has a side of9-26 A.U.X-Rudiogranzs of Strained Crystals have been studied by A. F.Joffe and M. V. Kirpit~heva.~' In the case of rocksalt, graduallyloaded by means of an electromagnet, when the limit of elasticityis passed the Laue spots elongate, and even before it is reachedthe spots elongate and break up into stratifications, increasing innumber with the strain, due to different small crystals into whichthe crystal breaks up, each of the same structure as the originalcrystal. The molecules glide along the plane of the rhombic dodeca-hedron and also rotate.The method is suitable for determiningthe limit of elasticity, and the mode of destruction. A methodis also described which gives on two photographs the strains inevery direction, and enables all the constants of elasticity to bedetermined from one small crystal.A.U.Crystallographic Chemical Investigations.The last two papers of the writer's research on the hexahydrateddouble selenates were read to the Royal Society on March 14thlast, and published shortly afterward^.^^ They relate to themanganese and cadmium groups of double selenates. Sufficientwas said in last year's report (pages 231 to 234) concerning thisprolonged investigation-which includes not only this large groupof monoclinic double salts, R,M(SeOp),,6H,0, but also the simplerhombic normal sulphates and selenates of t,he alkalis, R,SeO,,SS35 R.M. Bozorth, J . Amer. Chem. SOC., 1922, 44, 1066; A., ii, 499.313 R. W. G. Wyckoff, ibid., 1994; A., ii, 765.37 A. F. Joffe and M. V. Kirpitcheva, Phik. Mag., 1922, [vi], 43, 204.38 A. E. H. Tutton, Proc. Roy. SOC. 1922,[-43, 101, 226, 245; A., ii, 502,505.K 260 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.75 salts in all having been very fully dealt with-to render morethan passing notice in this Report superfluous. It will suffice tosay that at the conclusion of the second (last) memoir, that onthe cadmium group, six pages are devoted to a general review ofthe whole research, and are followed by a complete list (with refer-ences) of the separate memoirs, 26 in number, in which the resultshave from time to time been communicated, and of six othersdescribing the new instruments devised for the work.The twomain results which stand out are (1) the progression of the wholeof the crystallographic and physical constants with the atomicnumber of the alkali metal, potassium, rubidium, or caesium, and(2) the iso-structure of the analogous rubidium and ammoniumsalts. But even the many minor results are proving of more thanpassing interest in the light of other contemporary research, especi-ally that concerning the structure of the atom and that broughtabout by the advent of X-ray crystal analysis; and it is highlysatisfactory that there is full agreement between all this that isfully substantiated and the writer’s results.A quotation of thelast paragraph of the h a 1 paper will perhaps best express it.“ Thus it has come about, by the time that the author has com-pleted his crystallographic investigation of these important iso-morphous series, that a full explanation of the results is affordedby the immense amount of real knowledge that has been accumulatedduring the same time concerning the structure and nature of thechemical atom, and that revealed by means of X-rays, from whichthe law of atomic diameters has been derived. It is thus highlysatisfactory that the work of Moseley, Sir J. J. Thornson, Langmuir,the Braggs and the author should so perfectly agree in giving usa wider and fuller understanding of the nature of crystals, and ofthe structure of the solid matter of which they are the organisedexpression, than could have been expected or anticipated at thetime when the author’s researches on these isomorphous series wereinitiated.”The Dissociation Pressures of Hydrated Cupric Alkali Xulphutesis the subject of an interesting paper by R. M. Caven and J. Fer-gus0n.~9 The salts investigated were the copper group of doublesulphates, R,S04,CuS04,6H,0, in which R is potassium, rubidium,czesium, ammonium, or thallium. The results agree with the writer’sconclusion in the research just referred to, that there is a clearincrease in the electropositive character of the alkali metal in passingfrom potassium, through rubidium, to caesium.They are expressedin the curves reproduced in Fig. 11. They indicate that the waterof crystallisation is held more firmly, the greater the electropositive-39 R. M. Caven and J. Ferguson, T., 1922,121, 1406CRYSTALLOGRAPHY AND MINERALOGY. 261new of the alkali metal, and also that the heat evolved in the corn-bination of the lower hydrate (with 2H,O) with water also increasesas the electropositive character of the alkali metal advances inFIG. 11.0 Ascending temperature. x Descending tenzperature.160'14012070 80"Temperature.Vapour Pressures of Copper Group of Double Sulphates.strength. Moreover, the affinity of the process shows very markedlythe same variation. The positions of thallium and ammoniumrelative to rubidium and caesium in the series of alkali metals,as determined by these experiments, accord with those assignedto them by the writer from observakions of the morphological an262 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.physical properties of their salts.This practically verbatimquotation from the conclusions of Caven and Ferguson forms awelcome confirmation from a new standpoint.A Crystallographic and Optical Study of s m e Inorganic CmplexSalts has been made by Miss Isabel E. Knagg~.~O The first of thesubstances dealt with is potassium ferri-oxalate, [Pe(C20,)3]K3,3H,0,which crystallises with holohedral monoclinic symmetry and hasbeen already investigated by F. M. Jaeger, with whose data thisnew measurement agrees. The second substance is the analogousaluminium compound, in which aluminium replaces the iron,and which is shown to be truly isomorphous.A number of stillmore complicated compounds having cis- and trans- forms wereinvestigated, and some rather surprising cases of apparent iso-morphism observed.At the meeting of the Mineralogical Society on November 7th,1922, Miss Knaggs also gave an account of the crystals of someinteresting carbon compounds of the four types CX,, CX3Y, C(CX,),,and C(CX2Y),, where X and Y are other elements. Those of thefirst and third types, containing only one other element than carbon,appear to be usually cubic, while those of type 2 are trigonal orhexagonal, and those of type 4 tetragonal. The symmetry of thecrystal thus resembles to a considerable extent that of the mole-cule, suggesting that there may be only one molecule in the crystalunit in these cases of more symmetrical molecules. It will be highlyinteresting to have these cases investigated by means of X-rays,so as to ascertain whether this is really the case, especially in thelight of Shearer's rules.Physical-crystallogra~hic Investigations.The Piemelectricity of Rochelle Salt forms the subject of a paperby E.K. Some large crystals, weighing 100 grams or more,were used, and the piezo-electric effect was very pronounced whenthey had received prolonged drying, fist with alcohol and subse-quently a t 40". Crystals showing " hour-glass " marking affordedthe effect best of all, by the application of a twisting couple aboutthe principal axis of the crystals.Potentials as high as 500 voltswere developed. The crystals may be used for the reproductionand transmission of sounds.A New Optical Property of Biaxial Crystals has been observed byC. V. Raman and V. S. T a m ~ a , , ~ using a plate of aragonite cutperpendicular to the acute bisectrix of the optic axial angle.40 (Miss) Isabel E. Knaggs, T., 1922, 121, 2069.4 1 E. K. Scott, Trans. Paraday SOC., 1922,17, 748; A., ii, 609.C. V. Raman and V. S. Tamma, Phil. Mag., 1922, [vil, 43, 610CRYSTALLOGRAPHY AND MINERALOGY. 263Although the object used is a plate bounded by parallel faces,it forms a real erect image, with unit magnification, of a pinholeor other small source or object, illuminated with monochromaticlight.A luminous filament may be used instead of a pinhole, to vary thephenomena. The image is formed by light which travels throughthe crystal along an axis of single ray velocity.The Sixes of Atoms in Crystals.-The values given by U7.L.Bragg for the diameters of the atoms of such elements as have yetentered into crystals examined by X-rays, from which he deducedhis important law of atomic diameters, and which were quoted onpage 229 of the last Report, have on the whole been remarkablyconfirmed by work published during 1922. Thus R. N. PeaseP3fmds the following interatomic distances, the values of Bragg beinggiven afterwards in brackets : in diamond 1-54 (1*54), in silicon2-30 (2.35), in grey tin 2.80 (2.80), in silicon carbide 1.92 (1*90),in zinc blende 2.41 (2.35), and in cuprous chloride 2.41 (2.43).Also an investigation of the viscosity of silicon hydride, SiH,, byA.0. Rankine and C. J. Smith * has yielded further confirmationand support.If white light be used, a spectrum is afforded.New Minerals.Quite a considerable number of new minerals have been announcedduring the year 1922, of which the following may be mentioned,including a rich find of radioactive minerals a t Katanga in theBelgian Congo.Becquerelite, described by A. S ~ h o e p , ~ ~ is a radioactive mineraloccurring at Katanga as yellow crusts of small orthorhombiccrystals on pitchblende, It contains 86.5 per cent. of U03, and ispractically U0,,2H20.Dewindtite, also described by Schoep,46 was also found at Katanga,and is a radioactive yellow powder of the composition4Pb0,8U0,,3P*Ob, 12HzO.Xoddite, also a radioactive mineral from Katanga described bythe same author:' occurs as orthorhombic crystal aggregates of thecomposition 12U03,5Si0,,14H,0.Stasite, found a t Kasola, Katanga, again described by S~hoep,*~has the same composition as dewindtite, the substance being di-43 R.N. Pease, J . Amer. Chem. SOC., 1922, 44, 769; A., ii, 428.44 A. 0. Rankine and C. J. Smith, Proc. Physical SOC., 1922, 34, 181 ; A., ii,45 A. Schoep, Conzpt. rend., 1922, 174, 1240; A., ii, 450.46 Idem, ibid., 623; A., ii, 305.4 7 Idem, ibid., 1066; A., ii, 451.Idem, ibid., 875; A., ii, 356.709264 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.morphous.It occurs as golden-yellow, flat prisms, and also differsin density from dewindtite, as well as in crystal form and in colour.CeruleoJibrite, described by E. F. H0lden,4~ is a basic chloro-arsenate of copper, CuC1,,~Cu,As,08,6Cu( OH),, which was found asradiating tufts of bright blue fibres, orthorhombic needles, on cupritefrom Arizona.Gillespite, described by W. T. SchalleryW was found in an Alaskanmoraine as scaly masses, and appears to have the compositionFe”Ba Si401,.Sincosite, also described by S ~ h a l l e r , ~ ~ is a hydrous calciumvanadyl phosphate, CaO,V2O,,P,O5,5H2O, from Sincos, Peru.It forms uniaxial plates belonging to the uranite group.Melanouanudite, described by W. Lindgren, L. F. Hamilton,and C. Pala~he,~a occurs as bunches of black, monoclinic needleson a black shale from Minasragra, Cerro de Pasco, and has thecomposition 2Ca0,3V,0,,2V,04.Thorueitite is a silicate of scandium found at Saetersdalen, Norway,in large, greyish-green, monoclinic prismatic crystals resemblingepidote. It appears to be (Sc,Y),Si,O,, analogous to thalenite.It was discovered and described by J.Schetelig.=New Books and Editions.Prof. F. Rinne (Leipzig) has produced during 1922 new editionsof his two books “ Das feinbauliche Wesen der Materie nach demVorbilde der Kristalle,” published by Gebruder Borntraeger,Berlin, and “ Kristallographische Formenlehre und Anleitung zukris tallographisch- op tischen rontgenographisc hen Un tersuchungen , ”published by Max Janecke, Leipzig. The former contains excellentportraits of von Groth, Hauy, Schoenfiies, Fedorov, Tschermak,von Laue, Debye, Schemer, Sir W.H. Bragg, and W. L. Bragg. Itis full of illustrations and diagrams of an original character, includingmany of Prof. Rinne’s own X-radiograms of crystals. It regardsthe whole achievement of X-ray analysis as having revealed the truenature of the fine structure of solid matter. The second and laterbook is also very original inasmuch as it gives a readable accountof crystal phenomena and ordinary elementary Crystallographyfrom the aspect of one steeped in the later X-ray analytical work.In July there was published by Thomas Murby & Co. a bookof 152 pages by Mr. T. V. Barker, Lecturer in Chemical Crystallo-49 E. F. Holden, Amer.Min., 1922, 7, 80; A . , ii, 516.50 W. T. Schaller, J . Washington Acad. Xci., 1922, 12, 7.51 Idem, ibid., 12, 195; A . , ii, 450.52 W. Lindgren, L. F. Hamilton, and C. Palache, Amer. J . SC~., 1922, [v],53 J. Schetelig, Norsh. Beol. Tihskr., 1922, 6, 233; A., ii, 306.3, 195; A., ii, 305CRYSTALLOGRAPHY AND MINERALOGY. 265graphy a t Oxford, on “ Graphical and Tabular Methods in Crystallo-graphy.” In it are described the methods of crystallographicpractice which Mr. Barker has made his own, largely following themethods of V. Goldschmidt and Zedorov, especially those involvingrapidity of work and concise expression. It is a most valuablecompendium of the more recent and useful graphical methods.A so-called “third” edition by W. E.Ford of Dana’s “ TextBook of Mineralogy,” with an extended treatise on crystallographyand physical mineralogy, has been published in New York. Itforms a rejuvenated, very much enlarged, and fairly up-to-daterevision of the great text book of 1877, the total issues of whichin its many editions and re-issues are estimated to have reached27,000.The second edition of the writer’s “ Crystallography and PracticalCrystal Measurement ” was published by Messrs. Macmillan andCo. in March, in two volumes of 760 and 686 pages respectively,the first edition having been comprised in one volume of 946 pages.Each volume is in two parts, the total of 6Q chapters being thusdivided into four parts. These are : Part I, Crystal Form andGoniometry ; Part 11, Crystal Structure and its X-Ray Analysis ;Part 111, Crystal Optics and Microscopy; and Part IV, CrystalChemistry, Deformational Physics and its Interferometry.A ninth List of new Mineral Names, by Dr. L. J. Spencer, wasissued in 20 pages with the September number of the MineralogicalMagazine. A concise description is given of each of the mineralsincluded. Mineralogists and crystallographers are again indebtedto Dr. Spencer not only for this further most useful, long list,but, with some assistance from collaborators, for the MineralogicalAbstracts, which are now regularly issued by the MineralogicalSociety, with the -iWineralogical Magazine. Volume I of theseAbstracts, just completed, contains no fewer than 1254 abstracts,extending from the year 1915 to 1922. In spite of the considerablecost entailed by their publication, it is very satisfactory that theSociety has decided to continue this most valuable addition to themagazine.Concluding Remarks.In concluding this epitome of the crystallographic and mineralo-gical work of the year 1922, mention should be made of the highlyinteresting special number of “ Die Naturwissenschaften ” entitled“ Zehn Jahre Laue-Diagramm,” which was issued in April, contain-ing eight articles by authors who have contributed to the subjectof the X-ray analysis of crystals since its inception by Dr. M. vonLaue in the year 1912. They include Prof. von Laue’s collaboratorsK266 ANNUAL REPORTS ON THE PROQRESS OF CHEMISTRY.in the first discovery, Drs. Friedrich and Knipping. The formergives a most interesting account of the circumstances of the originaldiscovery, in the midst of the remarkable coterie of experts at thattime in Munich, which included Rontgen, von Groth, Ewald,Sommerfeld, and Laue. The origin appears to have been a discus-sion between Laue and Ewald as to how the minuter electromagneticwaves would behave with gratings of a similar small order of dimen-sions, and an enthralling description is given of the excitementamong the whole scientific circle at Munich when the experimentwas tried by Friedrich and, after a preliminary failure owing tonot having hit off the right conditions, so admirably succeeded,and the diffraction or reflection of X-rays by the planes of atomsin crystals became an accomplished fact. Indeed, the excitementwas still high when, that same summer, both Fedorov and the writervisited von Groth a t Munich, and were shown the first X-radiogramsof zinc blende.This Report is but a very inadequate attempt to do justice to theamount of valuable research which has been carried out during theyear 1922. But sufficient will doubtless have been written to showthat the tenth anniversary of the inauguration of this new weaponof research, and the centenary of Pasteur, the discoverer of thetrue nature of tartaric acid and of the meaning of its optical activity,is marked by a richness of result that the discoverers in the years1912 and 184s respectively could never have foreseen, still less haveanticipated; and that the promise of a still richer harvest yet to begleaned by the earnest workers of the future is so bright and alluringas to afford the highest encouragement to those who are makingthis branch of natural knowledge their special domain.A. E. H. TUTTON

ISSN:0365-6217    

DOI:10.1039/AR9221900234

出版商:RSC    

年代:1922

数据来源: RSC

摘要:

SUB-ATOMIC PHENOMENA AND RADIOACTIVITY ,*Introduction.TJNDER the title ‘‘ Sub-atomic Phenomena and Radioactivity ” areincluded in a broad sense all phenomena directly associated withthe central nuclei of atoms, as opposed to the so-called chemicalphenomena which we now know to be connected with the behaviourof the planetary electrons occupying the outer domains of theseatoms. This Report will therefore be concerned with the massesof individual atoms determined by physical means, the isotopicconstitution of the chemical elements, and their spectra, in so faras these are affected by isotopy. It will also deal with work onthe constitution of the nuclei themselves and the manner in whichthey may be disintegrated artificially. All phenomena connectedwith the spontaneous disintegration of the more complicatednuclei are, of course, included in radioactivity.During the past two years advances have been made in all thesebranches and some valuable steps taken towards elucidating thestructure of the nucleus itself.Among the more important ofthese should be mentioned the studies on artificial disintegrationand other phenomena of nuclear collision made by Rutherford andhis colleagues, and the application of the quantum theory to explainthe relation between p-rays and the y-rays which produce them,by Ellis and others. Progress in this direction is also promisedby the discovery of divergences from the whole-number rule, butthe accuracy of comparison of atomic masses will have to beadvanced considerably beyond that at present available before muchinformation will be obtainable from this line of attack.The Isotopic Constitution of the Elements.The work in’this field during 1921 has been already summarisedin the Report for that year.1 During 1922, several more elementshave been successfully investigated and other additional resultsobtained.Dempster has applied his method of positive rayanalysis to calcium and zinc, and the composition of five moreelements has been determined by means of the mass-spectrograph.The theory of the latter instrument has been satisfactorily worked* This Report covers the years 1921 and 1922.Ann. Rep., 1921, 18, 34-35.267 K* 268 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.out mathematically2 and a notable advance in its technique hasbeen made by the use of specially treated photographic plates.These results are summarised below.Aluminium.-Results obtained by the mass-spectrograph whenpure chlorine was present in the discharge tube and had reactedwith the aluminium electrodes leave very little doubt as to theconstitution of this metal.Aluminium may be regarded as asimple element of atomic weight 27, as its chemical atomic weightwould lead us to su~pect.~CaEcium.-By the treatment of this metal in the same way asmagnesium Dempster has been able to show that calcium hasa principal isotope 40 with a weaker component 44.Ch.Zorine.-It is now reasonably certain that this element doesnot contain any appreciable quantity of an isotope 39.6Iron.'-This element has been investigated by means of itsvolatile pentacarbonyl.Its mass-spectrum is characterised by astrong line a t 56 and possibly a very faint one at 54. The measure-ments on the former indicate a value slightly less than a wholenumber, but the divergence is within the experimental error.2inc.This metal was analysed by Dempster a t the same timeas calcium. The results indicate that it consists of four isotopesthe masses of which, by comparison with the calcium line 40, aregiven as 64, 66, 68, and 70. The first appears the strongest com-ponent and the last is very feeble.XeZenium.8-The mass-spectra of selenium were obtained by aspecial device by which the element itself was vaporised in thedischarge tube. The results were very definite and show that itconsists of six isotopes 74, 76, 77, 78, 80, 82.Isotope 74 is onlypresent in minute proportion. No divergence from the whole-number rule could be detected.Tin.g-By the use of its volatile methide, this element has beenshown to consist of seven, or possibly eight, isotopes, as given inthe following table. Measurement of their masses indicates that,although their differences are integral to the highest accuracy, themasses themselves tend to be 2 to 3 parts in 1000 less than wholenumbers on the oxygen scale. This is the first definite divergenceobserved since that of hydrogen, and it cannot be attributed toexperimental error in measurement on the following account. TheF. W. Aston and R. H. Fowler, Phil. Bag., 1922, [vi], 43, 514; A., ii, 241.F. W.Aston, Nature, 1922, 110, 664; A., ii, 844.A., 1921, ii, 402.Physical Rev., 1922, 20, 631.F. W. Aston, Nature, 1922, 110, 664; A . , ii, 844.Idem, ibid., 312; A., ii, 710. 8 Idem, ibid., 664; A., ii, 844.@ Idem, ibid., 109, 813; A., ii, 650SUB-ATOMIC PHENOMENA AND RADIOACTIVITY. 269lines of xenon were present on the plate, hence the line 135 due toSn120CG should have appeared exactly half-way between the twostrong xenon lines 134 and 136. It was actually unmistakablynearer the former. Whether this large divergence, which is about0.3 in atomic weight, represents the accumulated divergence ofboth elements, cannot be settled, although it is most probable thattin diverges more from a whole number than xenon.In any case,it is remarkable that it should occur in two elements so near inatomic number as tin and xenon.Antimony. lO-The mass-spectrum of antimony consists of twostrong lines, 121, 123, the former being slightly the more intense.Very faint lines also appear a t 122, 124, but these are ascribed tohydrides. The masses of the two isotopes of antimony are probablyslightly less than whole numbers. The results show that the oldvalue for the atomic weight, 120.2, is definitely wrong, but theyare in good agreement with the value recently obtained by Willardand McAlpine.Xenon.-The mean atomic weight of this element estimated fromits mass-spectrum is distinctly higher than the accepted valueobtained from the density by Moore.ll In order to ascertainwhether the discrepancy could be put down to the presence ofkrypton as an impurity, a sample of the actual gas used in thedensity determinations was analysed by means of the mass-spectrograph. The results showed no appreciable presence ofkrypton, so that the difference remains unexplained.The twodoubtful isotopes, 128,130, have been confirmed,l2 and two extremelyfaint probable additional ones have been detected at 124, 126.13From the table of results on p. 270, some interesting statisticalrelations are at once apparent. In the nucleus of the atom thereis never less than one electron to every two protons; in otherwords, the atomic weight of the lightest isotope of an elementcannot be less than twice its atomic number, except in the case ofhydrogen.The excess of the atomic weight over twice the atomicnumber has been called the isotopic number by Harkins. Thenumber of isotopes of any one element shows definite limits andtends to increase with atomic number. It is also greater for ele-ments of even than for those of odd atomic number; in the lattercase, it is never greater than two. The number of electrons inthe nucleus tends to be even, that is, in the majority of cases evenatomic number is associated with even atomic weight and oddlo F. W. Aston, Nature, 1922, 110, 732; A . , 1923, ii, 32.l1 " Isotopes," p. 114.l2 F. W. Aston, Nature, 1922, 109, S13; A . , ii, 650.la Idem, ibid., 110, 664; d., ii, 844270 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY .Elernen t .H ............He ............Li ............GI ............B ............c ............N ............0 ............F ............Ne ............Na ........................ 3 ............Si ............P ............s ............A ............K ............ca ............Fe ............Ni ............Zn ............As ............Se ............Br ............Kr ............Rb ............Sn ............CI ............Sb ............I ............ x ............cs ............Hg ............Table of Elements and Isotopes .Atomicnumber .123456789101112131415161 7 1s19202628303334353637505153545580Atomicweight .1.0083.996.949.110.912.0014.0116-0019.0020.2023.0024.3226.9628.331.0432-0635.4639-8839.1040.0755-8458.6865-3774.9679.279.9282.9285.45118.7121.77126.92130.2132.81200.6Minimumnumber ofisotopes .1121211112131211222(2)((41)62627 ( 8 )21,7 (9)(0)1Masses of isotopes inorder of intensity .1.00847.6911. 101214161920. 222324. 25. 262728. 29. (30)313235. 3740. 3639. 4140. 4456. (54) ?58. 6064. 66. 68. 707580. 78. 76. 82. 77. 7479. 8184. 86. 82. 83. 80. 7885. 87120. 118. 116. 124. 119.121. 123127129. 132. 131. 134. 136.128. 130. (126). (124)133117. 122. (121)(197-200). 202. 204(Numbers in brackets are provisional only.)with odd .If we plot the first 40 natural numbers and show thoseoccupied by known elements as in the figure. a curious relation1 2 3 9 5 6 7 8 9 10.11 12 13 14 25 10 17 L8 19 201 IN^ I N ~ I M ~ ~ M ~ I M ~ ~ A P ~ si [ ICllA(C11 /KIA121 22 23 2 4 25 2 8 ' 2 7 28 29 30 31 32 33 34r 35 36 37 38 39 40may be noticed. namely. that the simple recurring series 2. 3. 5.8 - -. of which each term is the sum of the two previous terms.is in every case. up to 34. represented by a gap . This relation maybreak down at the next term. if manganese has an isotope 55. butthis is not yet known .1sobures.-These are substances having the same atomic weighSUB-ATOMTC PHENOMENA AXD RADIOACTlVITY. 27 1but different chemical properties.They have been well knownfor some years among the radioactive elements, but among thenon-radioactive ones, although it was perfectly certain they mustexist, none was actually observed until Dempster showed that theprincipal isotope of calcium had an atomic weight 40 and so wasisobaric with the principal isotope of argon. Since then, theseleniums 78, 80, 82 have been found isobaric with kryptons, andone tin 124 with a probable xenon. If we disregard the doubtfulisobaric pair Sb, Sn 121, every pair has for one of its members aninert gas, and all the isobares (including the radioactive ones)have atomic weights which are even numbers.Periodic Systems of Elements and Isotopes.Many new periodic systems of the'elements have been put for-ward by Bourgerel,14 Oddo,l5 Partington,16 Kirchhof,17 Masson,l*Broek,19 Kohlweiler,20 and others.Some of these are worked outtheoretically on some physical basis, for example, the purely spec-ulative idea that all elements are the results of radioactive dis-integrations. Others are convenient schemes of representing thenumerical values obtained by experiment in such a way as tobring out certain interesting points. The most complete schemeof this kind is that of Harkins, which has been elaborated by himin numerous publications 21 to which the reader is referred. In avaluable table given in one of his most recent papers 22 is to befound a remarkably complete summary of the facts and reasonablespeculations in this field. In this diagram, against their atomicnumbers, are plotted the " isotopic numbers " of all atomic speciesknown and probable.They lie in a band of roughly paraboliccurvature which widens as it gets further from the origin. Theprobable constitutions of elements, not experimentally analyseda t the time the scheme was drawn up, are admittedly speculativeand dependent on the trustworthiness of the chemical atomicweight determinations. The accuracy of the predictions in thecases of selenium and antimony is-very striking a t first sight, andshows how much can be done by the judicious use of general andstatistical relations such as those given in the previous paragraph.14 Mon. Sci., 1920, 10, 241; A., 1921, ii, 102.16 auzzettu, 1920, 50, 213; A., 1921, ii, 102.16 Chem.News, 1920, 121, 304; A., 1921, ii, 103.l7 Physikal. Z , , 1920, 21, 711; A., 1921, ii, 103.18 PhiZ. Mag., 1921, [vi], 41, 281; A., 1921, ii, 191.19 Physikal. Z., 1921, 22, 164; A,, 1921, ii, 295.20 Ilbid., 243; A,, 1921, ii, 689.21 A., 1921, ii, 445, 583, 690; 1922, ii, 490, 702.22 W. D. Harkins, J. 8Tankiin Inst., 1922, 194, 645272 ANNUAL REPORTS ON THE PROGRESS OB CHEMISTRY.The Constancy of Chemical Atomic Weight and the Relation of theLatter to the Mean Weight deduced from the Results of the Mass-spectrograph.As soon as the isotopic nature of some common and widely dis-tributed elements had been definitely proved, it became of interestto determine with the greatest care the atomic weights of suchcomplex elements from sources as widely distributed as possible.Differences might be expected from two causes; either the processof origin of the element might be different at different points ofthe earth's surface, yielding isotopes in different proportions, orelements of the same original constitution might have their meanweight changed by some natural process which tended to bringabout partial separation of the constituent isotopes.Severalpieces of work have been performed with a view to test this point.Baxter and Parsons 23 compared the atomic weight of nickel frommeteorites with that of ordinary terrestrial nickel, but no differencewas found beyond that expected from experimental error. (Mlle)Curie has compared the atomic weight of chlorine from severalminerals with that of chlorine from sea-water. I n the case oftwo, the marine origin of which was in the highest degree unlikely,no difference was found.Chlorine prepared from a sample ofsodium chloride obtained from a desert region in Central Africagave a value slightly above Chlorine from an ancientmineral, apatite, from Balme has also been investigated 25; nodifference from normal chlorine could be detected. Taking intoconsideration the age and origin of the mineral, it may be con-cluded that the chlorine a t the time of the formation of the mineralsof the primary magma contained the two isotopes in the sameproportion as it does to-day, or that the two isotopes were thenformed in constant proportions.Boron is an element well suited for this test, for its isotopes differby 10 per cent.in mass and are both present in considerable propor-tion. Monro26 has compared the atomic weight of boron fromsome New Zealand minerals with that of the element obtained frompure sodium borate; here again no difference could be detected.Finally, Bronsted and Hevesy 27 measured the density of mercuryfrom minerals of different origin and found no divergence higherthan that corresponding with a difference in atomic weight of0~000A0~0012.23 J . Amer. Chem. SOC., 1921, 43, 507; A . , 1921, ii, 338.24 MlIe Irene Curie, C'ornpt. rend., 1921, 172, 1025; A., 1921, ii, 396.25 Mlle Ellen Gleditsch and B. Samdahl, ibid., 1922, 174, 746; A . , ii, 281.26 T., 1922, 121, 986.2 7 Nature, 1922, 109, 813; A., ii, 645SUB-ATOMIC PHENOMENA AND RADIOACTIVITY. 273The accumulation of negative evidence of this kind is veryimpressive, and supports the idea, already put forward, that theevolution of the elements (apart from those produced by radio-active disintegration) must have been such as to lead to a pro-portionality of isotopes of the same element which was const,antfrom the start, and since we know of no natural process of separation,has remained constant ever since.Although no accurate determinations of the relative intensityof mass-spectrum lines has yet been carried out, their relativestrengths can be approximately estimated.Hence the meanatomic weight of a complex element can be deduced in some caseswith considerable accuracy, and therefore provides a valuablecheck on the figure obtained by the ordinary chemical methods.In most cases, the agreement has been good, but in a few the dis-crepancy is considerable.28 It is satisfactory to note that duringthe past year redeterminations of the chemical atomic weightshave removed the discrepancy in several cases.Thus the revisionof the atomic weight of boron by two independent determinations 29gives 10.83 and 10.82, respectively, figures agreeing much betterwith that estimated from the mass-spectrum, 10.75 rt: 0.07, thandid the previous values, 11.0 and 10.90. Again, positive rayresults 30 indicate that glucinum is a simple element, whereas theold value for the atomic weight, 9.1, differs so far from a wholenumber as virtually to deny this possibility.This discrepancyhas now been removed by the redetermination of the chemicalatomic weight by Honigschmid and Bir~kenbach,~l who obtaina value 9.018. The cases of antimony and xenon have alreadybeen alluded to, that of krypton is still unexplained.Atomic Volume of Isotopes.-Soddy 32 has compared the valuesobtained for the density and atomic weight of ordinary lead, leadfrom thorite, and lead from uranium minerals. He concludes thatthe atomic volumes cannot differ by so much as three parts inten thousand and the atomic diameters by so much as one partin ten thousand.The Spectra of Isotopes.Series Spectra.-Merton has repeated his experiments on theisotopes shift of the line X 4058 of lead 33 and extended his measure-28 See F.W. Aston, “ Isotopes ” (Arnold, 1922), p. 114.2s G. P. Baxter and A. F. Scott, Science, 1921, 54, 524; A,, ii, 285; 0.Honigschmid and L. Birckenbach, And. Pzk. Quim., 1922,20, 167; A., ii, 641.30 G. P. Thomson, Phil. Mug., 1921, [vi], 42, 857; A., 1921, ii, 675.3l Ber., 1922, 55, [B], 4; A., ii, 214.32 Nature, 1921, 107, 41; A., 1921, ii, 698.33 Ann. Rep., 1920, 17, 224274 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ments to other lines. Using a very pure sample of uranium leadfrom Australian carnotite, he obtained the results indicated inthe following table : s4A A(Carnotite lead) Wave number (ordinary lead)[--h(ordinary lead) ] [-Wave-number (carnotite lead)]4058 0.011 f 0-0008 0.065 f 0.0053740 0.0074 f 0.0011 0.053 f 0,00836384 0.0048 f 0-0007 0.035 f 0.0053640 0.0070 f 0.0003 0.052 & 0.0023573 0.0048 f 0.0005 0.037 f 0.004It will be noticed that the shift for the line X 4058 is rathermore than twice that obtained before.Merton suggests that themost probable explanation of this difference is that the carnotitelead used was a purer sample of uranium lead than that obtainedfrom the pitchblende residues. It is also apparent that the differ-ences are not the same for different lines, an interesting and somewhatsurprising result.McLennan and Ainslie35 have subjected the light from a stronglithium arc to the highest resolution and find that the line X 6708consists of a close quartet with separations of 0.128 A., 0.173 d.,and 0.165 8. He suggests that these are the doublets of the isotopesof lithium, Li6 and Li7, although the intensity relations betweenthem are by no means in accordance with this view unless a newtheory is adopted.He proposes that, from these displacementsand the displacements in the case of lead, the isotope displacementscan be very closely obtained by multiplying the displacementcalculable on the Bohr theory by the atomic number of the respec-tive elements. In a later paper 36 on the absorption of X 5460.97by luminous mercury vapour, he describes satellites which heconsiders are due to the isotopes of mercury and quotes displace-ments agreeing with the empirical rule given above, but here againthe intensity relations are not satisfact,ory. M e r t ~ n , ~ ~ recentlycommenting on these results, points out that the measurements ofthe enhanced lines of helium agree perfectly with the Bohr theory,and therefore definitely contradict McLennan’s rule connectingatomic number with displacement.He also raises severdl exceed-ingly strong arguments against the possibility of the lithiumdoublets being in any way connected with the isotopic constitutionof that element.The difference between series spectra of isotopes is discussed gener-34 Proc. Roy. SOC., 1921, [ A ] , 100, 84; A., 1921, ii, 611.85 Ibid., 1922, [ A ] , 101, 342; A., ii, 541.313 J. C. McLennan, D. S. Ainslie, and (Miss) F. M. Cab, Proc. Roy. Soc.,a7 Nature, 1922, 110, 632; A., ii, 803.1922, [A], 102, 33; A . , ii, 728SUB-ATOMIC PHENOMENA AND RADIOACTIVITY.275ally by Ehrenfest,S8 Bohr,39 and Nicholson.4* Ehrenfest maintainsthat the ordinary Bohr formula, v2 : v1 = M , / B , + m :M,/M, + m,where MI, M,, and m are respectively the masses of the nucleiof the isotopes, and of the electron, and vl and v2 the frequenciesof the corresponding lines, cannot be true in general. Bohr ad-mits that the effect of the mass of the nucleus on the spectrumof an atom containing more than one electron is a complexproblem; not only may the mass effect disappear completely, butalso may be different from that calculated for an atom with oneelectron. Nicholson points out that the large separation observedby McLennan in lithium cannot be explained by the quantumtheory, and suggests that the new series may be a combinationseries or a spark series.Band Spectra.-The wave-lengths of the higher members of theband spectrum of uranium lead and ordinary lead have been com-pared by Grebe and K ~ n e n .~ l The chosen wave-lengths lie between4257.690 and 4281.458 A.U. Measurements of eighteen linesshow that the wave-length of the line corresponding with uraniumlead is on the average 0,055 B.U. shorter than that for ordinarylead. This figure agrees so far as its order is concerned with theassumption that the diatomic molecules are the carriers of theband spectrum.Infra-red Spectra.-The extreme smallness of the isotope shiftexpected in the spectra discussed above is due to the fact thatone unit of the vibrating system is the electron itself, the mass ofwhich is extremely small compared with that of the other unit,the nucleus.Very much larger effects'are to be expected wheretwo nuclei are concerned. Loomis42 shows that the doubling ofthe absorption bands in the infra-red spectrum of hydrogen chloride,first observed by Imes, can be explained on this view and gives avery satisfactory confirmation of the isotopic nature of chlorine.The frequencies of the doublets due to isotopes should be approxi-mately proportional to l/(ml + m,)/qm2, where ml is the massof the hydrogen nucleus and m2 the mass of the charged halogenatom; hence the band lines should differ by 111330. The averageinterval measured was 14 A.U. or 4.5 wave numbers, which agreeswith the calculated vaIue of 4.3 wave numbers, Hydrogen fluoridedoes not show this effect, and in the case of hydrogen bromide thecomputed separations are too small to be observed as yet.38 Nature, 1922, 109, 745; A., ii, 598.39 Ib;d,, 746; A., ii, 598.40 Ibk?., 1922, 110, 37; A., ii, 599.81 Physikal.Z., 1921, 22, 546; A,, ii 4.$2 Aetrophy8. J., 1929, 52, 248276 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Separation of Isotopes.Much work on the artificial separation of isotopes has beenperformed during the past two years, but nevertheless success hasonly been achieved in the case of two elements, mercury andchlorine. The work of Bronsted and Hevesy on the formera isparticularly convincing both on account of the beauty and sim-plicity of the method used and the remarkable fidelity with whichthe resulh follow the theory, also fortunately simple.They foundthat if mercury is distilled a t so low a pressure that moleculesescaping from the surface of the liquid never return, and if at thesame time the rate of distillation is kept down to a point a t whichthe mixing of the liquid by self-diffusion is practically perfect, thenthe molecules of the different isotopes distil at rates inverselyproportional to the square roots of their masses. In consequence,the lighter isotopes tend to increase in the first fractions and theheavier ones in the last residues of the distillation process. Intheir final work, 2700 C.C. of mercury were fractionated system-atically to about 1/100,000 of the original volume in each direction.The density of the original mercury being taken as unity, the lighterfraction (0.2 c.c.) had a density 099974, and the heavier (0.3 c.c.)1.00023. This corresponds with a difference of 0.1 of a unit inatomic weight. Using the same method with a solution of hydro-chloric acid, they were later able to obtain evidence of a separationcorresponding with 0.024 of a unit in the atomic weight of chlorine.44Egerton45 announces a partial separation of the isotopes of zincby the same method.A change of about 0.05 of a unit has been achieved by Harkins 46and Anson Hayes:' who used a method of diffusion through pipe-clay similar to that originally used in the separation of the isotopesof neon.48 The system of diffusion was elaborate, large quantitiesof material were employed, and the experiments occupied a longperiod. In this and in a later comrnuni~ation,~~ the theory of theresolution of isotopic mixtures by diffusion is discussed at somelength and it is suggested that slight separation of isotopes occursduring ordinary distillation under reduced pressure.Mulliken 50gives a very complete theory of the separation of isotopes by thermal43 2. physikal. Chem., 1921, 99, 189; Phil, Mag., 1922, [vi], 43, 31; A., ii,140.44 Nature, 1921, 107, 619; A., ii, 280.Oii Ibid., 1922, 110, 773; A., 1923, ii, 28.46 J . Amer. Chem. SOC., 1921, 43, 1803 ; A., ii, 140.47 Ibid.4 * A., 1919, ii, 209.49 R. S. Mulliken and W. D. Harkins, ibid.. 1922, 44, 3 7 ; A., ii, 295.6O Ibid., 1033; A., ii, 492SUB-ATOMIC PHENOMENA AND RADIOACTIVITY.277diffusion and by centrifuging, and shows that the latter method islikely to be of more value in the case of isotopes of high atomicweight. A special method, named evaporative centrifuging, isproposed whereby gas condensed in the periphery of the centrifugea t high speed would be allowed to evaporate very slowly, the lightfractions being drawn off very gradually a t low pressure from thecentre of the apparatus. It is suggested that this method oughtto yield a separation ten to fifteen times as great in one operationas would diffusion or evaporation. He also discusses the possi-bility of separating liquid isotopes by centrifuging, a method whichhas been considered by P o ~ l e . ~ l An attempt to test this theoryin the case of mercury proved unsuccessful, and its failure isattributed to slight vibration of the centrifuge.Kohlweiler 52 still maintains the opinion that he has separatedthe isotopes of iodine, although the existence of these is contraryto the direct evidence of the mass-spectrograph.He ascribes hisresults to isotopes present in too small quantities to be detected bythat apparatus. If this is the case, i t is very difficult to understandhow it could be possible to obtain the relatively enormous shift-0.88 of a unit-claimed, by any diffusion method.Perhaps the most surprising report is that from Dublin claimingthe separation of lead isotopes by chemical means.53 Lead chloridewas prepared from a mixture of ordinary lead and thorium lead,and the reaction represented by the equation BPbCI, + 4MgRX =R,Pb + 2MgC1, + 2MgX2 + Pb carried out.The lead tetraethyland metallic lead constitute the fractions which are used separatelyin a repetition of the process. By two repetitions a separationindicated by relative atomic weights 207.1 and 207.4 is claimed.This result will need very strong confirmation before i t is generallyaccepted, for the method is founded on an observation of Hoffmannand Wolf 54 in 1907 that a large separation of lead from radium-Dcould be effected by a single reaction with magnesium phenylbromide. This statement was in direct contradiction to all thework of the most careful experimenters a t that date, it has neverbeen confirmed since, and is regarded by the most competentauthorities in radioactivity to-day as probably erroneous.Other possible methods of separation have been put forward.Skaupy 55 suggests that the differential effect of electronic impacts51 Phil.Mag., 1921, Ivi], 41, 818; A . , 1921, ii, 403.b2 2. physikal. Chem., 1922, 101, 218; A., ii, 497.53 T. DiUon, R. Clarke, and V. M. Hinchy, Sci. Proc. Royal Dublin SOC.,1922, 17, 53; A., ii, 710.54 Ber., 1907, 40, 2425.66 2. Physik, 1920, 2, 213; A., 1921, ii, 154278 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in an electric discharge would give a s.eparation of isotopes of therare gases. Ludlam 56 describes experiments carried out to test amethod of separation of the isotopes of chlorine based on a sugges-tion made by Sir J. J.Thomson that the number of impacts persecond of the molecules of a gas on a surface will be in the inversesquare roof of their mass. Hydrogen chloride a t a pressure of afew centimetres of mercury was passed over ( a ) a water surface,and ( b ) ammonia gas, and a small fraction allowed to remain un-combined. No change in molecular weight was observed aftereither process. An ingenious photochemical process has alsobeen in~estigated.~' If chlorine consists essentially of a mixtureof three parts of CP5 and one part of CP7, the molecules shouldbe present in the proportions CP5, : CP5CI37 : CP7, = 9 : 6 : 1. If lightwhich has passed through a column of such chlorine enters a mixtureof chlorine and hydrogen, the initial reaction should use up thethree types of molecules in the proportions 1 : lo9 : lox, and thehydrogen chloride formed should be almost entirely HCP7.Theexperimental results, however, of applying this method were entirelynegative.In conclusion, i t may be pointed out that the actual numericalresults achieved by lengthy and laborious operations in the fewsuccessful attempts indicate very clearly that unless some entirelynew means of attack is devised no serious practical disturbance ofthe constants of chemica.1 combination need be anticipated in theimmediate future.ArtiJicial Disintegration of the Lighter Elements by the Collision ofThe remarkable results in this field obtained by Rutherford andChadwick during the year 1921 have already been reported,58and a complete account of their work up to February 1922 willbe found in Sir Ernest Rutherford's lecture before the ChemicalSociety.59 In a more recent publication,6* these results have beenconfirmed and extended.The nature of the particles ejected fromthe various elements during the bombardment by swift a-particleshas been directly investigated by measuring their deflexions in amagnetic field. The results show that in the cases of aluminium,phosphorus, and fluorine the particle ejected is a single positivelyB G Proc. C a d . Phil. SOC., 1922, 21, 45; A,, ii, 497.5 7 H. Hartley, A. 0. Ponder, E. J. Bowen, and T. R. Merton, Phil. Mag.,58 Ann. Rep., 1921, 18, 31.69 T., 1922, 121, 400.60 Sir E. Rutherford and J. Chadwick, Phil. Mag., 1922, [vi], 44, 417;Swift a-Particles.1922, [vi], 43, 430; A., ii, 280.A., ii, 682SUB-ATOMIC PHENOMENA AND RADIOACTIVITY.279charged hydrogen nucleus, which is now regarded as being identicalwith the ultimate atom of positive electricity or proton. The sameis also probably true of boron and sodium. The ranges of theprotons ejected, in the forward and backward directions, fromnitrogen, aluminium, boron, fluorine, sodium, and phosphorus havebeen more accurately determined. In all cases, the protons wereejected in all directions, and the maximum range in the backwarddirection was less than in the forward direction. The maximumranges, in cm. of air, of the ejected protons, in the forward andbackward directions, respectively, were found to be : boron, 55and 38; nitrogen, 40 and 18; fluorine, 65 and 4 8 ; sodium, 58 and36; aluminium, 90 and 67; and phosphorus, 65 and 49.Only inthe case of nitrogen was the maximum range in the backwarddirection much less than that of the protons produced by thebombardmeat of hydrogen itself. No protons of range greaterthan 30 cm. of air, in a forward direction, were ejected from eitherlithium or glucinum, and there is no evidence of the ejection oflong-range protons from magnesium, silicon, or chlorine. It is avery remarkable thing that of the series of elements from hydrogento potassium so far examined the active elements (those from whichhigh-speed protons can be ejected) are odd-numbered in the orderof atomic number in sequence 5, 7, 9, 11, 13, 15. The atomicmasses of these active elements are all expressed by 4n + a, wheren is a whole number and a = 3 for all except nitrogen and the lighterisotope of boron, for which a = 2.With the one exception of boron,all are simple elements.It is evident from these results that the nuclei of even light elementsare very complex structures. The effects mentioned above are bestexplained by the view that the fragile nuclei of the active elementshave a different proton-electron structure from those not exhibitingdisintegration, and that their fragility is due to the presence ofwhat may be called " planetary " protons less firmly bound thantheir fellows and probably rotating in orbits of nuclear dimensions.The fact that chlorine and the heavier elements do not break upmay be ascribed to their nuclear charge being so high that the M-particle never makes a close enough collision to effect disintegration.Disintegration is clearly akin to ionisation, since in each case aunit electric charge is torn violently away from the atom, butbeyond this the parallel ceases.In the case of ionisation the fieldof force round the atom is of a sign which attracts the electrondislodged, or any other electron, and extends indefinitely in alldirections, so that the atom is sure to regain its neutral form veryrapidly. On the other hand, in disintegration, any field of forcetending to regain the proton lost is confined to nuclear dimension280 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.and in addition is surrounded indefinitely in all directions by afield of force repelling such a positive charge.The effect of ionisationis therefore transitory, whilst that of disintegration is permanent,and it is not unreasonable to speculate that when a proton is dis-lodged from an atom of sodium (Na=) there results an atom ofneon (Ne22) which, as soon as it has lost its excess eleotron, will beindistinguishable in any way from any other atom of Ne22. Evenif the actual effect is not so simple as this, there can be no doubtthat alchemical transmutation has been achieved. An attemptmade by Wyckoff 61 to effect transmutation by bombardment oflithium salts by a stream of electrons, in the hope of introducingone or two into the nuclei of the lithium atoms, was unsuccessful.The claim put forward by Wendt and Irion 62 that tungsten isdecomposed and partly transmuted into helium when, in the formof a fine wire, it is electrically deflagrated a t a very high temperature,appears so excessively improbable that i t may be safely left forfurther confirmation.a- Rays.The range of a-rays in solids and liquids has been measured byTraubenberg.In the first case,G3 a small-angled wedge of thematerial was arranged with its lower face parallel to, and a t adistance of a few millimetres from, a plane surface activated bymeans of radium-C. The upper face of the wedge was in contactwith st zinc sulphide screen. The range of the a-rays in the solidwas determined by observing the distance of the line of demarc-ation between the light and dark regions of the screen from theangle of the wedge.Correction was made for the thickness of airtraversed. p-Radiation was eliminated by a powerful magneticfield. The following results were obtained for the respective ranges,expressed in 10-4 cm., in the various elements stated: lithium,129.1 ; magnesium, 57.8 ; aluminium, 40.6 ; calcium, 78.8 ; iron,18.7 ; nickel, 18.4 ; copper, 18.3 ; zinc, 22.8 ; silver, 19.2 ; cadmium,24.2 ; tin, 29-4 ; platinum, 12.8 ; gold, 14.0 ; thallium, 23.3 ; lead,24.1. These results can be correlated by a formula, but heliumand lithium do not satisfy this relation ; this discrepancy is ascribedto the production of secondary a-radiation.the range was measured by immersingthe activated plate in the liquid and lowering the screen towardsi t until i t just fluoresced; the thickness of the liquid was thenIn the case of6 1 Science, 1922, 55, 130; A., ii, 642.62 J.Amer. Chem. SOC., 1922, 44, 1887; A., ii, 773.63 2. Physik, 1920, 2, 268; A., 1921, ii, 148.64 H. R. von Traubenberg and K. Philipp, Physikal. Z., 1921, 22, 687;A., ii, 12SUB-ATOMIC PHENOMENA AND RADIOACTIVITY. 281measured with a horizontal microscope. The range in water wasfound to be 6Op. Gases were investigated by passing the beam ofrays parallel to the sides of a glass wedge, containing the gas, andplacing in their path a screen a t a small angle with the horizontal.As in the case of solids, the range was deduced from the boundaryof dark and light on the screen. They found that the stoppingpower of gases varies as the square root of the atomic number, butis not strictly additive in the case of compounds.The luminous path of a-rays in crystals has been observed byGeiger and Werner.65 A thin, highly polished section of willemitewas arranged in the field of a microscope so that the a-rays ofpolonium should strike i t a t a small angle.Luminous lines, 0.03 mm.long, were seen. These represent the path of the a-ray in the crystaland show that the number of centres is extremely large, and in thecase of a perfect crystal sufficient to ensure a scintillation for everya-particle hitting the crystal.Some exceedingly important observations on the collisionsbetween a-particles and hydrogen nuclei have been made by Chad-wick and Bieler.66 The angular distribution of these nuclei, orprotons, projected by a-particles of mean range 6.6 cm., has beendetermined up to an angle of 66".The distribution for ct-rays ofmean ranges 8.2, 4.3, and 2.9 cm. has been obtained over a smallerrange of angle. The number of protons projected within thesesmall angles by u-rays of high velocity is greatly in excess of thatgiven by forces varying as the inverse square of the distance betweenthe centres of the two nuclei. The manner in which the numberof protons projected varies with the velocity of the rays has beenobserved over a wide range. For rays of high velocity this variationis in the opposite direction to that given by the inverse square law ;for those of range less than 2 cm.the collision relation is aboutthe same as that expected from the inverse square law. Theexperimental collision relation is compared with those calculatedby Darwin for various models of the particle, and the conclusionis drawn that the a-particle behaves in these collisions as an elasticoblate spheroid of semi-axes about 8 x 10-13 and 4 x cm.,moving in the direction of its minor axis. Outside this surfacethe force varies approximately as the inverse square of the distancefrom the centre of the spheroid.Slater 67 has investigated the hard y-radiation which is emittedwhen cc-particles from radium emanation impinge on metals suchas lead and tin. The radiation differs but little with change ofO 5 2. Physik, 1921, 8, 191; A., ii, 183.g6 Phil.Mag., 1921, [vi], 42, 923; A., ii, 12.6' Ibid., 90.1; A . , ii, 13282 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.atomic number. The absorption coefficients in lead are 1.8-1 cm.for lead and 2.1-1 cm. for tin. The intensity obtained is small, andis about 50 per cent. greater for lead than for tin. It appears to beemitted fairly uniformly in all directions, but differs in all otherrespects from the characteristic radiations, and is probably emittedfrom the nuclei of the atoms in the radiator after direct collisionwith the a-particles. Shenstone 68 has attempted to detect theinduced radioactivity resulting from a-ray bombardment. Heshows that the violent dismemberment of a molecule by an a-particle does not give rise to unstable nuclei, capable of emittingmass particles of a range greater than 2.0 mm.Also no cumulativeeffect is observable after a heavy bombardment by the or-particles.These negative results do not preclude the possibility of disintegra-tions taking place which involve the emission of p-particles ory-radiation.The velocity of a-rays from polonium has been measured directlyby MTle Irene Curie G9 by means of a magnetic deviation method.A value of 1.593 x lo9 cm. per second is obtained and the ratio ofthe emission velocities of the a-rays of polonium compared withthose of radium-C is accordingly 0.829, which is in excellent agree-ment with the ratio 0.826 obtained from the cube roots of theirpenetrating powers. An interesting point is raised by Henderson 70in a communication entitled " a-Particles as Detonators." If it isconsidered that when an a-particle passes through matter thematter in its proximity is momentarily raised to a high temperature,the detonation of certain unstable substances would be expectedto take place on exposure to the action of these particles.Air-driednitrogen iodide is detonated in this way. The detonation is notcaused by the first a-particle which happens to strike the substance,but appears to be a probability effect. The same investigator 71has measured the ionisation curves of a-particles from radium-C,thorium-C',, and thorium-C, in air, particular attention beingdirected to the end portions. The greater part of each curve isapproximately a straight line.The gradual flattening of thecurve a t the end of the range can be accounted for by small variationsin the ranges of individual or-particles. He suggests that an extra-polated range is more suitable than the usual definition. Theextrapolated range in air at 0" is 6.592 cm. for radium-C, 4-529 cm.for thorium-Cl, and 8.167 cm. for thorium-C,.Phil. Mug., 1922, [vi], 43, 938; A . , ii, 377.6@ Compt. rend., 1922, 175, 220; A,, ii, 606.'O Nature, 1922, 109, 749; A., ii, 606.'1 Phil. Mag., 1921, [vi], 42, 538; A., 1821, ii, 617SUB-ATOMIC PHENOMENA AND RADIOACTIVITY. 283The Scattering of p-Rays.Geiger and Bothe 72 have measured the scattering of @-rays bythin metal sheets (a) in the regions of small scattering angle (6 = 15"or less) and ( b ) in the regions of large scattering angle (4 = 60" ormore). They show that there is a fundamental difference betweenthe two types of scattering. In the region of smaller angles, theobserved angle is produced by the superposition of many individualsmall scattering angles through which the @-ray is bent as it passesthe individual atoms (multiple scattering), whilst in the region oflarge angles the superposition plays a subordinate r6le; eachscattering angle is produced by a single collision when the pathof the electron lies very close to the nucleus of the atom collidedwith (individual scattering).In the case of rays from radium-(B + C), they show that for the very thinnest layers the scattering isless than that demanded by the square root law, but that forthicker layers this law is confirmed.The same phenomenon has been very completely investigatedby Crowther and S~honland.~~ A source of radium emanation ofan initial activity equivalent to that of 45 mg.of radium wasemployed and the scattering of the p-rays caused by foils of gold,silver, copper, aluminium, and carbon was measured over rangesof both large and small angles. In the experiments on the relationbetween the transmitted radiation and the thickness of the scatteringmaterial, they conclude that this is a linear one for thin foils. Ift,is the thickness of material sufficient to cut down the radiationto one-half its initial intensity, their results may be summarisedby stating that, for light elements such as carbon and aluminium,the scattering as measured by +/dG is independent of + over thewhole range of the angles investigated (4" to 18O), but has a valuewhich is nearly twice that to be expected on the current theories ofthe effect.On the other hand, for heavy elements like gold orplatinum, the scattering for very small values of d, approximatesclosely to that to be expected from theoretical considerations, butincreases rapidly with the angle, until for angles of 18" it is inagreement with the larger scattering shown by the lighter elementsa t all angles measured.Their method of viewing the data strongly suggests that somechange is required in the present theory when the distance betweenthe path of the @-particle and the deflecting particle is less than acertain critical value.Glasson 74 has tabulated values of the atomic absorption,phg8ikaz. Z., 1921, 22, 585; A., ii, 13.78 Proc.Roy. SOC., 1922, [ A ] , 100, 526.74 Phil. Mag., 1922, [vi], 43, 393; A., ii, 183284 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.a = d / D , and the atomic scattering, b = PAfD (where A is theatomic weight, D the density, and a and P are the coefficients ofabsorption and of scattering, respectively, for p-rays) of the ele-ments, and has discovered two interesting relations. He findsthat the values of a are approximately constant for elements inthe same period of the periodic system. Thus for Mg,Al, a = 89 ;for Fe,Co,Ni,Cu,Zn, a = 172-196 ; for Pd,Ag,Sn, a = 260-268 ;and for Pt,Pb,Au,Bi, a = 348-372. These figures are in theratio 1 : 2 : 3 : 4, so that it seems likely that the value of u is aperiodic function of, the atomic number.The value of b increaseswith atomic number and is approximately represented by theexpression b = 0.36 x N2.O9.p-Rays, 7-Rays, and the Xtructure qf the Nucleus.The comparative lack of experimental data connected with thestructure of the nucleus gives a very free field to speculative theoryon that subject. The nucleus model put forward by Meitner75has been discussed by Neuberger, Valeras, and its originator in anumber of papers of a speculative and controversial nature.76Other types of models are put forward by Gehrcke," Chwol~on,~~and Stewart.79has examined the magnetic spectrum of the p-rays excitedby the "-rays of radium-B in uranium, lead, platinum, tungsten,and barium.He shows that the main lines are formed by electronsejected from the K-rings of these elements by definite y-rays, eachtype of y-ray being characterised by a certain energy. In a laterpaper,sf he develops a method, based on the quantum theory, bywhich the wave-length of 7-rays, too short to be measured by thecrystal method, can be determined, and applies this to the casesof the 7-rays of radium-& radium-C, and thorium-D. The methodconsists in the determination of the energies of the different linesin the natural p-ray spectrum of the element in question, and theenergy of the corresponding line in the excited spectra of substancesof neighbouring atomic number. The numerical results obtainedsupport the view that the y-rays are emitted from the nucleus.They also suggest that the quantum theory is applicable to thenucleus, and a part, a t least, of the structure of the nucleus isexpressible in terms of stationary states.75 2.Physik, 1921, 4, 146; A,, ii, 293.'13 A., ii, 107, 183, 185, 416, 702, 732, 733.7 7 A., 1921, ii, 323.7 8 A., ii, 209.iD A . , ii, 277.Proc. Roy. Xoc., 1921, [ A ] , 99, 261; d., 1021, ii, 422.8 1 C. D. Ellis, ibid., 1922, [ A ] , 101, 1 ; A . , ii, 339.ElliSUB-ATOMIC PHENOMENA AND RADIOACTIVITP. 285MeitnerYs2 on the other hand, although admitting that the originof the 7-rays is the nucleus itself, gives an entirely different ex-planation of Ellis’s results on the basis of her nucleus model,developed by the application of the quantum theory by Smeka1.*3The Meitner-Smekal theory supposes that the primary cause ofy-rays are p-rays of definite energies, and on it the well-knowncontinuous p-ray spectrum must be considered to be entirelyadventitious and produced under experimental conditions by somesuch agency as scattering. Ellis’s explanation, which is more inaccord with the older work of Chadwi~k,~~ is that the disintegrationelectrons form the continuous spectrum. The homogeneous groupsare considered to be entirely secondary in origin and due to theconversion of y-rays in the electronic structure of the radioactiveatom, these y-rays being emitted from the nucleus during thedisintegration.85 Chadwick and Ellis 86 have made a preliminarymeasurement of the intensity distribution in P-ray spectra ofradium-B and radium-(?, under conditions which enabled scatteringeffects to be eliminated or corrected for.Their results show thatin each case by far the greater part of the intensity is in the con-tinuous spectrum, a fact exceedingly difficult to explain on theMeitner-Smekal theory, and are generally in strong support of thatput forward by Ellis.The work on p-rays caused by 7-rays is still in progress and hasalready raised points of very great interest. It suggests that theorigin of some of the electrons forming the p-rays must be insidethe K-ring and therefore within the nucleus itself, and that theseelectrons have energies corresponding with definite quantum levels,just as the ordinary planetary electrons outside are known to have.Now the effect of an isotopic difference in the structure of nucleimay be expected to have an enormously greater effect on p-rayspectra caused by nuclear electrons than it would have on X-rayor ordinary light spectra caused by planetary electrons.Multiplelines observed already give evidence that some of the heavy elementsexamined are mixtures of isotopes, but, unfortunately, none of thesehas yet been analysed by the mass-spectrograph. It is also clearthat if an electron is dislodged from the nucleus by the agency ofa y-ray produced in the nucleus itself, it is just possible that thesame effect could be produced, and transmutation effected, by a7-ray from an exterior source.Assuming that the emission’ of82 2. Physik, 1922, 9, 131; A., ii, 416.83 Ibid., 1922, 10, 275.a4 Verh. deut. Physikd. Ga., 1914, 16, 383.8 5 C. D. Ellis, Proc. C a d . Phil. SOC., 1922, 21, 121; A., ii, 466.86 Ibid., p. 274286 ANNUAL REPORTS ON THE PROGRESS OF OHEMISTRY.7-rays may precede the process of disintegration, Hevesy 87 showsthat if the nucleus could take up the energy of a 7-ray from anexternal source it should change its stability and therefore its rateof disintegration. He has experimented with uranium in radio-active equilibrium with uranium-X, and with radium-D in equi-librium with radium-E, but has failed to detect a measurable changein the p-radiattion in either case.Thorium.Long-range Particles from Thorium-C.-h the disintegration ofthorium-C a small number of particles with the long range of 11.3 cm.are expelled.88 As there was a possibility that these had originatedby collisions of the a-particles with the oxygen of the mica absorbingscreen, the phenomena were re-examined with screens of aluminiumas well as mica.89 The same results were obtained in both cases.The ratio of the total number of particles with ranges exceeding8.6 cm.to the total number of a-particles (ranges 5.0 and 8.6 cm.)is 1 to 11,000. At least 90 per cent. of the long-range particlesoriginate in the active deposit. Measurement of the deflexion ofthese particles in a magnetic field showed that they were ordinarya-particles of mass 4. There is no information as to their source.It may be that thorium-C may break up in two ways with theemission of rays of ranges 8.6 and 11.3 cm., or that 1 in 11,000 ofthe atoms of thorium-C breaks up directly with emission of thesevery swift a-particles.The resulting product would have anatomic number 81, and would be an isotope of thallium with atomicweight 208. The amount of this thallium found in thorium mineralsshould be about 0-00004 per cent.The number and the range of the recoil atoms of thorium-Cand thorium-C' have been investigated by Kolhor~ter.~~ Aluminiumfoil, activated by a mesothorium preparation, was used as a sourceof the radiation. It is concluded that a recoil atom results fromeach atom of thorium-C and thorium-C' transformed by the emis-sion of an a-ray. The average ranges found in hydrogen were0.55 mm.and 0.96 mm., respectively, corresponding with ranges of0.129 mm. and 0.224 mm. in air at 15" and 760 mm.A determination of the number of a-particles per second emittedby thorium-C of known 7-ray activity has been made by Shenstoneand S c h l ~ n d t . ~ ~ The a-particles were counted by the wheel method8 7 Nature, 1922, 110, 216; A., ii, 608.Sir E . Rutherford, Phil. Mag., 1921, [vi], 41, 570; A., 1921, ii, 293.A. U. Wood, ibid., p. 575; A., 1921, ii, 294.2. Physik, 1920, 2, 257; A., 1921, ii, 149.@l Phil. Mag., 1922, [vi], 43, 1038; A., ii, 417SUB-ATOMIC PHENOMENA AND RADIOACTIVITY. 287devised by Rutherford, and accurate y-ray measurements weremade at the same time as the counts. Counts made with thorium4and radium-C showed that the ratio of their a-ray activities forequal y-ray activities is not independent of the thickness of thewall of the y-ray electroscope.The volatility of a radioactive product, deposited on metal, hasbeen examined in the case of thorium-B and thorium-C, depositedon gold, platinum, and palladium.92 A discontinuity a t about760" is put down to the occurrence of thoriurn-C oxide stable a tthis temperature,Strong 93 has made a careful series of fractionations of a mixturecontaining radium and mesothorium obtained during the processof extraction from barium compounds. No separation whatevercould be detected, from which it is concluded that radium andmesothorium are true isotopes.Uranium and Actinium.Adams 94 points out that Piccard's assumption 95 that theactinium series is derived neither from uranium-I nor from uranium-I1 does not require the identity of the periods of the first and thethird.A hypothetical isotope of protoactinium (ekatantalum oruranium-2) is assumed as the parent of actinuranium by a p-raytransformation. He assigns to this element an atomic weight 235,corresponding with protoactinium 231, actinium 227, and actiniumlead 207, and points out that the last value agrees well with Honig-schmid's value of 206.05 for the atomic weight of uranium leadcontaining about 3 per cent. of actinium lead.Meyerg6 calculates the half-life period of actinium to be aboutsixteen and a half years, and the transformation ratio of the actiniumto the uranium family to be 4.2 per cent.Hahn and Meitner 97consider this value to be 25 per cent. too high, and prefer theirown value, 3 & 0.3 per cent. They consider that Meyer's prepara-tion probably contained 1-2 per cent. of ionium, which wouldexplain the difference. The same workers,98 by separation of theprotoactinium from uranium of approximately known age andmeasurement of its activity in comparison with that of uranium,have been able to estimate its half-life period as about 12,000 years.This value is the result of three concordant experiments and isv2 S . Loria, Krakauer Anzeiger, 1917, 260; A., 1921, ii, 294.93 J . Amer. Chem. Soc., 1921, 43, 440; A., 1921, ii, 294.v4 Ibid., 1920, 42, 2205; A., 1921, ii, 8.@5 A., 1918, 6, 6.s6 Wien. Anzeiger, 1920, 133; A., 1921, ii, 8.97 2. Physik, 1921, 8, 202; A., ii, 185.'* Ber., 1921, 54, [B], 69; A., 1921, ii, 150288 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRYto be regarded as the lower limit. It is thus possible to calculatethe protoactinium content of uranium minerals, which is expressedby the figure 72 mg. of protoactinium to one ton of uranium; thecorresponding figure for radium is 330 mg.New Radioactive Substances in Uranium.-Hahn 99 describes anew radioactive substance present in ordinary, uranium salts pos-sessing the chemical properties of protoactinium. It emits p-radiations and has a half-life period of six to seven hours. Theradiations are highly complex ; within the limits examined, thehalving thickness increases from 0.014 to 0.12 mm. of aluminium.Under the prescribed conditions, the intensity of radiation of thenew substance is only about 0.25 per cent. of that of uranium-X(uranium-Xl + uranium-XJ, obtained from the same quantity ofuranium. The parent substance can only be uranium-XI or anew uranium-XI isotope of similar life period. In the former case,uranium-X1 suffers a dual degradation of a type not yet observed.In the latter case, i t is probable that a new uranium degradationseries exists which has a small intensity of radiation and theindividual members of which can be arranged as isotopes in theknown uranium-radium series. Until the parentage of the newsubstance is definitely established, the author proposes to designateit “ uranium-2.” Neuburger 1 suggests possible types of disintegra-tion in the uranium-radium series to account for the occurrence ofthe new uranium-2. Hahn,2 however, rejects the transformationssuggested by Neuburger as improbable.have repeatedly measured the @-radiationof a quantity of uranium-X for a prolonged period. They showthat in addition to the hard @-radiation of uranium-X, there is asoft radiation which with increasing age of the preparation decreasesmore and more slowly; this indicates the presence of a substanceof longer life than uranium-X. They name this provisionally‘’ uranium-V.” It has a half-life period of about forty-eight hys,its p-radiation is half absorbed by an aluminium sheet 0*0003 mm.thick, and it may be a member of the actinium series. Hahn4has determined the decrease in activity of a number of uranium-Xpreparations to test these observations, but has found n o evidenceof the existence of uranium-V.Piccard and StahelP. W. ASTON.@@ Ber., 1921, 54, [B], 1131; A., 1921, ii, 478.1 Naturwiss., 1921, 9, 235; A., 1921, ii, 479.2 Ibid., 236; A., 1921, ii, 479.8 Physikal. Z., 1923, 23, 1; A., ii, 185.4 Ibid., 146; A., ii, 340

ISSN:0365-6217    

DOI:10.1039/AR9221900267

出版商:RSC    

年代:1922

数据来源: RSC

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INDEXAarnio, B., 207.Abderhalden, E., 186, 220, 232.Aboulenc, J., 91.Abribat, M., 17.Adams, C. E., 68.Adams, E. Q., 287.Adler, L., 197,Ainslie, D. S., 274.Albrecht, W. A., 209.Aldridge, J., 42.Allison, V. C., 168.Altwegg, J., 66.Aminoff, G., 255.Amos, A., 230.Andersen, E. B., 52.Anderson, J. A., 39.Anderson, J. H., 230.Anderson, P., 38.Anderson, W. T., 177.Annett, H. E., 174.Appleby, M. P., 42, 52, 59.Arai, M., 232.Arinstein, B., 230.Arinit, J. W., 139, 164.Arndt, C. H., 217.Arndt, F., 130.Arnold, R., 226.Arrhenius, O., 206, 213, 216.Arrhenius, S., 15.Asahina, Y., 137, 159, 160.Askenasy, P., 46.Astbury, W. T., 244.Aston, F. W., 268, 269, 273.Astruc, A., 225.Atkins, W. R. G., 216, 217.Atkinson, E., 171.Aubel, E., 230.Augested- Jensen, H.,* 13 7 .Auwers, K. von, 96, 133, 131, 13G,Azadian, A., 174.Akerlof, G., 19.143, 164.Backhurst, l., 250.Baeyer, A. V., 135.Bailey, G. C., 137, 141.Bailey, R. A., 65.OFBaker, H. B., 11, 36, 37.Baker, J. L., 232.Baker, M., 11, 35.Balaban, I. E., 143.Bales, S. H., 73.Ball, N. G., 218.Ballauf, F., 42.Baly, E. C. C., 22, 37, 55, 83, 218,Banting, 197.Barbier, A., 66.Bardwell, D. C., 41.Barker, T. V., 69.Barker, W. F., 218.Barlot, J., 170.Barlow, W., 236.Barnett, M., 200.Barnett, W. L., 73.Barratt, S., 2.Bartlett, H. H., 226, 227.Bass, L. W., 131.Bassett, H., 43.Batchelor, H. W., 21 7.Batelli, 191.Battegay, M., 92.Batuecas, T., 6, 35.Bau, A., 227, 230.Baudisch, O., 170, 171, 220.Bauer, E., 93.Bauer, F.C., 217.Baur, E., 230.Baxter, G. P., 34, 272, 273.Bear, F. E., 207.Bechhold, H., 165.Beck, R. P., 45.Reeker, .4. G.. 158.Becksr, J. E., 199.Becker, K., 13.Reckmann, E., 97.BBdos, P., 93.Beealey, R. M., 126.Behre, A., 173.Bell, J., 84.Benade, W., 135.Benary, E., 137.Bennett, A. Ii., 172.Bennett, C , . M., 55.Benrath, A, 48.220, 221.289 LAUTHORS’ NAME290 INDEX OF AUTHORS’ NAMES.Carey, C. A., 192.Carl, H., 8.Carlton, C. A., 176.Carmichael, M., 73.Carpenter, P. H., 208.Carpentier, G., 175.Carr, R. H., 169, 213.Carre, M. H., 219.Carter, E. G., 207.Case, F. H., 137.Castellani, A., 230.Catoire, M., 81., Caven, R. M., 42, 260.Berger, E. V.. 39.Berger, W., 224.Bergmann, A.G., 63.Bergmann, M., 77, 78.Berl, E., 167.Bernoulli, A. L., 123.Berry, A. J., 48.Bertrand, G., 225:Best, 197.Bettag, L., 94.Betti, M., 133.Beyer, P. H., 90.Bezssonoff, N., 208.Bieler, E. S., 281.Bijvoet, J. M., 41, 256.Biltz, H., 147.Biltz, W., 54.Binaghi, R., 65.Binapfl, J., 95.Birch, S. F., 115.Birckenbach, L., 34, 273.Bishop, (Miss) E., 26.Bishop, E. R., 181.Bistrzycki, A., 144.Bizzell, J. A., 209.Blair, E. W., 65.Blatherwick, N. R., 192.Bleyberg, W., 109.Blumenthal, &I., 17 7.Boas, F., 230.Bode, G., 225.Boeseken, L., 71.Bohm, K., 163, 229.Bohme, O., 146.Bottcher, B., 156.Boettner, F., 137.Bohr, N., 31, 275.Bokorny, T., 224.Bolsaneck, W., 135.Bonacker, I., 148.Bone, W.A., 21.Bonino, G. B., 17G.Bonnell, J., 59.Bonnet, E., 224.Boresch, K., 228.Bornstein, A., 195.Borsche, W., 148.Bosanquet, C. H., 14, 31, 250.Bose, A. K., 208.Bose, M. N., 174.Rothe, W., 283.Eotolfsen, E., 46.Bougault, J., 172.Bourgerel, G., 271.BOUSSU, R. G., 21.Bowen, E. J., 278.Boynton, W. P., 8.Bozorth, R. M., 257, 259.Bradshaw, G. G., 122.Brady, 0. L., 90, 91.Bragg, (Sir) W. H., 12, 13, 14, 89, 235,Bragg, W. L., 5, 31, 250.254.Bramley, A., 8.Brand, K., 92, 94.Brandt, Ph., 92.Brass, K., 132.Braun, J. von, 127, 128, 140, 151,Braunholtz, W. T. K., 153, 154.Breisch, K., 1i9.Brenet, (Mlle) M. T., IiO.Brenken, B., 144.Brenner, W., 223.Bridel, M., 226.Briner, E., 53.Brinton, P. H. M. P., 49.Britton, H.T. S., 45.Broche, H., 133, 136, 142.Broek, A. van den, 271.Bronsted, J. N., 272, 2iG.Brooks, M. M., 223, 230.Bruckhausen, F. von, 163.Brukl, A., 54, 167.Brunkow, 0. R., 230.Buck, J. S., 145.Buckley, H., 56.Buckner, H. K., 50.Budnikov, P. P., 177.Buell, H. D., 42, 175.Biirklin, E., 81.Bullis, D. R., 217.Burdick, C. L., 167.Burger, H. C., 57.Burgess, P. S., 211, 212.Burnett, A. J., 28.Burton, E. F., 26, 27.Bury, C. R., 32, 51.Buryhek, O., 44.Busch, H., 83.Buston, H. W., 184.Butkevitsch, V. S., 208, 230.155INDEX OF AUTHORS' NAMES. 291Cazaubon, 233.Chadwick, J., 2 i S , 281, 285.Chalupny, K., E79.Chandrasena, J. P. C., 64, 107, 114.Chapin, H. C., 34.Chapman, E. L., 15.Chaudin, A., 232.Chavanne, G., 61.Cherbuliez, E., 146.Chernoff, L.€I., 227.Chervet, D., 181.Chestnut, V. K., 227.Chibnall, A. C., 223.Chick, H., 199.Child, C. D., 2.Christie, G. H., 89.Chwolson, O., 254.Ciamician, G., 138, 223. 224.Ciferri, R., 217.Clark, A. W., 160.Clark, E. P., 226.Clark, G. L., 13, 30.Clarke, 196.Clarke, R., 277.Clarke, R. H., 18.Classen, W., 177.Clayson, D. H. F., 326.Clemo, G. R., 93.Clerici, E., 164.Clovcr, A. M., 67.Cobet, R., 230.Cohen, A., 175, 176.Colien, J. B., 74, 90.Coleman, G. H., 10%Colin, H., 232.Collie, J. N., 68.Collins, G. E., 5l.Collins, S. H., 226.Collip, J. B., 197.Collischon, H., 94.Comber, N. M., 206, 213, 314, 215.Combes, R., 219, 228.Compton, A. H., 250.Compton, A.K., 14.Conant, J. B., 129.Congdon, L. A., 171.Conner, S. D., 217.Conrad, (Miss) E., 152.Conrad, If., 100, 101.Cooper, E. A., 193.Corleis, W., 149.Correns, E., 97.Costantin, J., 227.Coster, D., 31.Costy, P., 233.Coward, (Miss) K. K., 193, 200.Crabtree, H. G., 145.Crespi, M., 3.5.Creiztzfeldt, TV. H., 44.Crocker, E. C., 88..(;Irowden, G. P., 193.Crowther, 283.Crowther, E. M., 213.Cruinp, L. M., 215.Cshyi, W., 231.Curie, (Mlle) I., 272, 252.Currey, G., 228.Curtis, W. E., 1.Curt'ius, T., 144.Cutler, D. W,, 218.Cutter, J. O., 7 5 .Cuttica, V., 45.Dafert, 0. 'iron, 22;.Dnkin, H. D., 84, 186, 191.Dalyell, E. L., 199.Damiens, A., 56.Daniels, F., 53, 56.Darwin, C. G., 249.Dauvillier, A., 32, 52.Dave-y, W.P., 257.Davidson, J., 223.Davies, TT7., 92, 131.Dax-is, E. 0. E., 41, 210.Davis, T. L., 84.Day, J. N. E., 91, 127.Debye, I?., 14.Decker, H., 144.Deighton, T., 169.Delauney, P., 226.Demjanov, N. J., 107, 116.Deinolon, A., 309.Demoussy, E., 224.Dempster, 268.Denham, H. G., 54.Denham, W. S., 82.Denison, J. A., 213.Dennett, J. H., 58.Dennis, L. M., 50, 51.Dennis, W., 174.Densch, 215.Dernby, K. G., 208.Ders, H. G., 89, 127.Deshapande, S. S., 110.Dessoulavy, E., 155.Detceuf, A., 66.Deuel, H. J., 170.Dickinson, R. G., 258.Dillon, T., 277.Dilthey, W., 138.Dimroth, O., 121, 150.Dixon, H. H., 218.Dixon, X., 189.Doctor, E., 56.Dodd, L4. H., 169.Doerr, R., 224.Dorries, W., l.43.Dojarenko, (Miss) M., 107, 116.Donovan, F.K., 172.DOX, A. W., 146.Drew, H. W. K., 69, 100.Driggs, F. H., 34.Drummond, J. C., 1'70, 193, 200,Duane, W., 13.202.L 292 INDEX OF AUTHORS’ NAMES.3uboc, T., 230.hbsky, J. V., 161.hchQ6ek, F., 231.Iuchoii, F., 232, 233.~ U C ~ O U X , H., 174.Xiring, A., 173.3iirrwiichter, E., 44.Dutzmann, A., 106.kfraisse, C., 69.Duncan, H. M., 37.Iunn, M. S., 187.gurrant, R. G., 43.htcher, R. A., 193.Dutoit, P., 166.Earl, J. C., 79.Ebler, E., 2;.Eder, R., 121.Egerton, A. C., 276.Rggert, J., 43.Eggert, S., 17.Ehrenfest, P., 276.Ehrhardt, G., 144.Ehrlich, J., 179.Ekkert, L., 171.Eldridge, E. F., 181.Elias, H., 194.Eliasberg, P., 232.Eller, W., 204.Ellis, C. D., 284. 285.Elsey, H.M., 39.Embden, G., 194.Emmert, B., 151.Enderlein, F., 68.Engeland, R., 147, 184.England, E. W., 170.Ephraim, F., 41.Erdenbrecher, A, 50.Erlenmeyer, E., 185.Ernstrom, E., 231.Ertl, K., 56.Eschenhagen, G., 43.Espenschicd, H., 48.Euler, A. C. von, 145.Euler, H. von, 230, 231.Evans, B. S., 178.Evans, W. L., 66.Evers, F., 4‘7.Evers, N., 176.Ewing, D. T., 27, 181.Ewing, W. W., 38.Fabre, R., 170.Faillebin, 62.Fairbrother, F., 52.Fales, H. A., 19.Faltis, F., 128.Farbw, vorm. Meister, Lueius &Farmer, X. H., 112, 133.Farmer, R. C., 39.Briining, 152, 155.Faurholt, C., 49.Faust, T., 121.Fazi, R. de, 80.Feist, F., 72, 73.Feist, K., 146.Fellenberg, T. von. 144.Ferpson, J., 42, 260.Fernbndez, O., 229.Fernbnch, A., 229.Fetkeiiheuer, B., 175.Fichter, F., 142.Fierz, H.E., 131.Finch, G. I., 53.Finks, A. J., 228.Fischer, E., 138, 147, 183.Fischer, H., 138.Fischer, TV., 177.Fisher, E. A., 202. 207, 213-Fleck, A., 42.Fleisclier, K., 123.Fletcher, 197.Fleury, P., 173.Flutsch, C., 68. 91.Foemter, F., 53.Fogg, H. C., 34.Foix, A, 49, 166, 17s.Folin, 0.. 174.Forster, >‘I. o., 151.Foster, D. L., 19-1.Foster, G. L., 184.Fowler, R. H., 26s.FrSinkeZ, S., 202.Fraenkel, W., 44.Franklin, E. C., 84.Franzen, €1.. 91, 227.Fraser, R., 8 i .Fred, E. B., 230, 231.Freeman, N. L., 250.Fresenius, L.. 212, 226.Freudenberg. K., 146, 226, 232.Freundler, P., 134.Freundlich, L., 106.Fricke, R., 173.Friedemann, W.G., 228.Friedrich, W., 46.Friend. J. A. N., 27, 58-Fries, K., 132.Fristor, F., 150.Fritschi, J., 63.Froelicher. V., 90.Fromm. E., 130.Fuchs, W., 108.Furth, O., 230.Fujita, A., 160.Funk, H., 50.Funke, G. L., 231.Futtemenger, A., 146.Gabriel, S., 127.Gadamer, J., 160, 163.Gainey, P. L., 21’7INDEX OF AUTHORS’ NAMES.Galizzi, A., 224.Garmendia, T., 229.Gehrcke, E., 284.Gehring, A., 168.Gehrke, M., 78.Geiger, H., 281, 283.George, H. J., 15.Gerhardt, N., 186.Gericke, W. F., 223.Gerlach, 215.Gerlach, W., 50, 256.Germann, F. E. E., 35, 43, 57.Germs, H. C., 52.Gerretsen, F. C., 217.Gersdorff, C. E. F., 228.Giaja, J., 232.Gilbert, L. F., 56.Gillot, P., 219.Glaser, L. C., 44.Glasson, J. L., 283.Glasstone, S., 51, 52.Gleditsch, (Mlle) E., 272.Gluud, W., 43.Godchot, M., 93.Goddertz, A., 147.Gomberg, M., 104.Gonzalez, F., 35.Goode, H., 180.Goodhue, E.A., 258.Gordon, N. E., 205, 207.Goris, A., 171, 233.Gortner, R. A., 184.Gottschaldt, E., 148.Grab, M. von, 229.Granacher, C., 141.Graham, H., 74, 103.Graham, J. J. T., 179.Grandchamp, L., 67.Grandmougin, E., 136,Graser, J., 231.Greaves, J. E., 207.Grebe, 275.Greene, H., 98.Grobet, E., 166.Groenewege, J., 232.Gros, R., 172.Gross, R. E., 186.Grude, F., 46.Guha, P. C., 130.Guillaumin, A. J. A., 172.Guillet, L., 46.Gutbier, A., 44.Guthzeit, M., 112.Gutman, M. B., 200.Gupta, 47.Gupta, B. M., 74, 101.Guye, P. A., 6, 35.Haagen, van, 34.Haar, A. W.van der, 80, 227.Haas, A. R. C., 217.Haber, F., 27.Hadding, A., 58.Haefelin, G., 147.Haeman, S. H., 72.Hahn, O., 287, 288.Halban, H. von, 23.Halberkann, J., 151.Haley, D. E., 232.Hall, D., 179.Haller, A., 93.Halpin, J. G., 201.Hamilton, L. F., 264>Hance, F. E., 51.Hanke, M. T., 185.Hanner, A., 170.Hantzsch, A., 100, 105, 135.Harden, A., 194.Harding, T. S., 173.Karkins, W. D., 27, 27-1, 276.Harned, H. S., 19.Harries, C., 47.Harris, J. E. G., 155.Hart, E. B., 201.Hartley, H., 11, 24, 278.Harter, L. L., 232.Hartmann, H., 45.Hartung, E. J., 43.Hasenbaumer, J., 2 17.Hasselblatt, M., 12.Hatcher, W. H., 41.Haworth, R. D., 68.Haworth, W. N., 79, 81.Hayes, A., 276.Haynes, D., 219.Hazleton, E. O., 171.Healy, D. J., 212.Heap, J.G., 148.Hebler, F., 165.Heck, A., 16.Hedvall, J. A., 58.Heide, K., 128.Heidelberger, M., 158, 159.Heike, W., 46.Heilbron, I. M., 83, 145, 218, 220,Heilner, G., 95.Heinze, B., 215.Helbig, O., 210.Helbronner, A., 210.Helferich, R., 78, 232.Heller, G., 135, 143.Helmick, H. H., 16G.Helwert, F., 227.Hembd, K., 225.Henderson, G. H., 282.Henderson, J. A. R., 172.Henderson, T., 74, 103.Henglein, F. A., 9.Henley, P. R., 194.Henrich, F., 141.Hbrissey, K., 80, 226.Herold, J., 137.Herzfeld, E., 230.Herzig, P., 174.Heslinga, J., 178.L 3293221it94 INDEX OFHess, A. F., 198.Hess, K., 82, 106, 149, 161.Hetterschij, C. W. G., 213.Hevesy, G. von, 272, 276, 286.Hewitt, J. A., 195, 230.Hickox, E.H. C., 131.Hiedmann, E., 52.Higginbotham, L., 70.Higson, G. I., 43.Hildebrand, J. H., 181.Hill, A. E., 44.Hill, A. J., 137.Hill, E. L. G., 193.Hiller, A., 185.Hilton, H., 252.Hilton, O., 69.Hinchy, V. M., 277.Hinshelwood, C. N., 11, 24.Hirsch, J., 75, 230.Hirsch, M., 175.Hirst, E. L., 74, 81, 82, 103.Hissink, D. J., 207.Hitchcock, D. I., 232.Hixon, R. M., 216.Hjort, J., 201.Honigschmid, O., 34, 273.Hoffman, A., 67.Hoffmann, F., 166.Hoffmann, W. F., 184.Hofmann, A. W. von, 153.Hofmann, J., 53.Holden, E. F., 264.Hollins, C., 139.Holm, K., 195.Hooft, M., 177.Hope, E., 70, 92.Hopkins, E. S., 34.Hopkins, F. G., 189.Hoppert, C. A., 201.Horn, T., 219.Hudig, J., 213.Hudson, D. P., 83, 218, 220, 221..Huebner, J., 83.Huckel, W., 116, 127.Hultenes, K., 133, 136.Huttig, G.F., 46, 57.Huggins, M. L., 32, 33, 88, 257.Hughes, W., 33.Hull, A. W., 255.Hulton, H. F. E., 232.H u e , M., 199.Hummel, J. J., 120, 146.Humphrey, G. C., 201.Hurst, E., 66.Hutchinson, H. B., 217.Iatrides, D., 229.Ikawa, M., 57.Ikeda, K., 184.Ingold, C. K., 3, 10, 64, 71, 72, 87,107, 111, 112, 114, 115, 125, 126,133.AUTHORS' NAMES.Ingvaldsen, T., 20 I.Irion, C. E., 39, 280.Irvine, J. C., 78, 79, 81, 82, 83.Ivanov, N. N., 232.Ives, H. E., 165.Jacobs, W. A., 158, 159.Jacobsen, H., 164.Jacobsen, P., 97.Jacoby, M., 219.Jadin, F., 225.Jaeger, F. M., 52.Jahn, R., 80.Jaloustre, 230.James, C., 34, 49.James, R. W., 14, 31, 250.Jameson, H.L., 200.Jancke, W., 13.Jenge, W., 44.Jenkins, W. J., 28.Jenssen, H., 143.Jirsa, F., 44.Joachimoglu, G., 230.Joffe, A. F., 259.Joffe, J. S., 209, 215.Johansson, H., 72.John, C., 160.Johns, C. O., 227, 228.Johnson, H. W., 212.Johnson, T. B., 131, 137, 171.Johnston, E. H., 53.Jonas, K. J., 204.Jones, A. J., 226.Jones, D. B., 228.Jones, D. O., 181.Jones, G. W., 167, 168.Jones, W. J., 148.Jonesco, S., 228.Jonescu, A., 176.Jonsson, E., 44.Jung, J., 225.Kahho, H., 223.Knllman, H., 15.KanG, N., 177, 181.Karlsson, K. G., 19.Karlsson, S., 230.Karraker, P. E., 212.Karrer, P., 81, 82, 84, 139.liarrer, S., 53, 5.5.Karssen, A., 41, 256.Kass, A., 202.Katinszky. H. v., 152.Kauffmann, H., 88.Kaufmann, A., 151.Kaufmann, H. P., 68.Kaye, F., 83.Keeler, R.F., 169.Keen, B. A., 206, 210, 211.Kelrrmann, F., 92, 106.Kelley, A. P., 216IN1)ES OF AUTHORS' NAMES. 295Kendall, J., 15.Kennedy, C., 193.Kenner, J., 75, 90, 125.Kerb, J., 229.Kerkow, F., 132.Kermack, W. O., 30, 60, 85, 129, 159.Kettridge, E. B., 181.Keyssner, E., 227.Kiesel, A., 223, 228.Kiliani, H., 77.Kindler, K., 158.King, H., 90, 101, 157, 160, 161, 229.Kjng, H. S., 32.Kmney, A. Mc. B., 129.Kinose, J., 232.Kirchhof, F., 271.Kirpitcheva, M. V., 259.Klcin, G., 228.Kleiner, 196.Klemmer, A., 168.Kling, A., 180.Knaggs, I. E., 262.Knoevenagel, E., 83.Knoth, 82.Knowlton, 196.Koch, P. P., 43.Konjg, J., 217.Konig, W., 153.Koessler, K.K., 185.Koctschau, R., 64.Kohler, D., 219.Kohler, L., 132.Kohlweiler, E., 2i1, 277.Kohn, AT., 107.Kolhorster, W., 286.Kolkrneycr, N. H., 255.Kollo, C., 1'79.Kolthoff, I. M., 171, 176, 178, 180,Kon, G. A. R., 110, 116, 127.Konen, H., 275.Korenchevslry, V., 199.Kostytschev, G., 219, 232.Kotake, M., 140.Kozlowski, A., 228.Kraemer, O., 109.Krafft, F., 127.Kraft, E., 94.Kramer, B., 196.Kraus, C. A., 15, 17.Krause, K. E., 177.Krauss, F., 59.Kreichgauer, A,, 101.KrBger, E., 217.Kropf, A., 166, 178,Kruger, E., 215.Krys, I?., 170.Kuhn, R., 231.Kuhr, C. A. H. von Wolzogen, 209.Kumagawa, H., 229, 230.Kuroda, C., 228.Kuroda, S., 141.Kurre, B., 57.181.Kurtenacher, A., 177.Kuwada, S., 137.Laborde, 230.Lambert, G., 168.Lammering, D., 95.Landauer, R.S., 38, 40.Landrieu, P., 76.Landrivon, J., 66.Landstrum, F. O., 41.Lang, N., 163.Lang, R., 178.Lange, C., 173.Lange, H., 133.J,angenbeck, W., 143.Langhans, 85.Langmuir, I., 30.Lantzsch, K., 210, 215.Lapkamp, K., 27.Lapworth, A., 30, 60, 68, TO, 99,Larson, A. T., 167.Larsonneau, A., 171.Laschtschcnko, P. N., 54.Lrzssieur, A., 180.Lauterbach, H., 181.Lavoye, 174.Leavenworth, C. S.. 228.Lecher, H., 53.Lecoq, R., 231.Lee, H. R., 181.Lehner, F., 171.Leitch, G. C., 79, 81.Lejeune, 61.Lemmermann, O., 212, 216, 216.Lenher, V., 56.Leonard, H. A., 170.Lepape, A., 39, 164.Lepine, R., 196.Leroide, J., 66.Leuchs, H., 152.Leulier, M., 230.Levene, P.A., 201, 202.Levi, G. R., 58.Lewis, G. N., 18.Lewis, H. B., 187.Lewis, H. F., 173.Lewis, J. H., 192.Lewis, W. C. McC., 19, 22, 23.Leyser, F., 47.Lieben, F., 230.Liebermann, L., 230.Liempt, J. A. M. van, 57, 1 7 5Light, L., 143.Lindberg, E., 230.Lindemann, F. A., 24.Lindgren, W., 264.Lindh, A. E., 255.Lindner, J., 131, 172.Lindner, K., 57.Ling, A. R., 79, 220.Lingen, J. S. van der, 2.iao296 INDEXLipman, J. G., 209.Lipmann, C. B., 222.Lipp, P., 108.Little, R. B., 192.Livingston, M. B., 224.Lizius, J. L., 176.Locquin, R., 66.Lodge, (Sir) O., 33.Lob, W., 194.Losch, J., 49.Lovgren, S., 233.Long, A. W., 217.Looker, C. D., 66.Loomis, A. G., 45, 275.Lorenz, R., 44.Loria, S., 287.Losana, L., 178.Lottermoser, A., 165.Lowry, T.M., 24, 25, 75.Lucasse, W. IV., 17.Ludlam, E. B., 278.Ludwig, E., 79.Lueck, R. H., 53.Luger, A., 224.Lund, Y., 207.Lundin, H., 232.Lush, E. J., 65.Lutz, O., 175.Lyman, J. F., 232.Lynn, E. V., 69.Lyon, T. L., 208.Maass, O., 41.McEain, J. W., 28.Macbeth, A. K., 74, 80, 103.McCay, L. R. W., 177.McCollum, E. V., 199.McCombie, H., 20.McCrosky, C. R., 42.MacDonald, A. I)., 123.Macdonald, J., 81.MacDougall, I). T., 223.MacDougall, F. H., 4, lS0.Mach, F., 169.McHargue, J. S., 225.McHatton, L. P., 26.Macht, D. J., 224.MacInnes, E. D., 27.Mack, K., 215.McKeehan, L. VJ., 255, 256McKenzie, A, 74, 76, 124.McLcan, H. C., 215.Maclean, J. S., 233.McLennan, J. C., 274.Macleod, 197.Mscleod, A.G., 174.McRae, J. A., 70.Macri, V., 174.Madelung, W., 69.Maestrinj, D., 231.Maihle, A., 69.Ma,jirna, R., 119, 140, 228.OF AUTHORS’ KAMES.Malfitano, G., 81.Malkomes, T., 78.Malvezin, P., 67.Mameli, E., 129.Manchot, W., 50, 56.Manley, J. J., 54.Mann, F. C., 73.Mannich, C., 95.Mansuri, Q. A., 54.Maquenne, L., 156, 224.Marais, J. S., 216.Marckwald, W., 84.Marcusson, J., 204.Mark, H., 104.Martin, C. J., 187.Martin, W. H., 213.Masing, G., 44.Massink, A., 176.Masson, I., 56.Masson, O., 271.Masters, H., 83.Mattson, S. E., 20G.Mayeda, S., 159.Mayer, P., 230.Mazza, L., 17.Meigs, E. B., 192.Meitner, L., 284, 285, 287.Meldrum, W. B., 42.Mellanby, 198.Mendelwitsch, A., 107.Menzies, A. C., 10.Mering, von, 196.Merrill, H.B., 179.Merton, T. R., 2, 273, 278.Merwin, H. E., 59.Meulen, R. ter, 172.Meyer, G., 16.Meyer, K. H., 68, 106.Meyer, J., 46, 56, 113.Meyer, P., 124.Meyer, S., 287.Meyerhof, O., 189.Michael, A., 130.&liehaelis, A., 134.Michel, E., 41.Niekeley, A., T8.Milde, E., 130.Millar, C. E., 210.Millar, E. J., 225.Miller, E. W., 232.Miller, H. G., 228.Milligan, L. H., 48.Mills, U7, H., 76, 149, 153, 164,Mingazzini, M., 118.Minkowski, 196.Minovici, S., 176, 179.Minton, T. H., 129.Mirande, M., 227.Missenden, J., 164.Misson, G., 179.Mitchell, A. D., 53.Mitchell, J. S., 211156INDEXMitscherlich, E. A., 218.Miyake, K., 208.Miyamoto, S., 61.Moller, H. P., 223.Norner, C.T., li5.Moggi, A., 139.Moir, J., 171.Mokrttgnatz, M., 225.Moldenhauer, H., 56.Moles, E., 35.Molisch, H., 219.Molliard, M., 230.Mond, R. L., 50.Monnier, R., 92.Monro, A. D., 272.Montmollin, H. de, 142.Moore, 269.Moran, T., 19.Morelli, R., 48.Morgan, G. T., 69, 100.Morrell, J. C., 19.Morris, J. L., 174.Mortimer, F. X., 11.Moser, L., 54, 56, 167, lil).Moser, (Miss) S., 129.Moureu, C., 39, 69, 164.Moyle, D. M., 194.Muller, C., 127, 218.Miiller, E., 65, 181.Muller, F., 46, 87.Muller, H., 65.Miiller, J. H., 51, 179.Mueller, 5. N., 184.Miiller, W., 160.Muira, I., 199.Muller, J. A., 166, 178.Mulliken, R. S., 37, 276.Mumm, O., 148.Murlin, J. R., 196.Murmann, E., 167.Mylo, B., 117.Myrback, K., 231.Nackay, H.M. M., 199.Nanji, D. R., 79.Neale, S. M., 16.Negelein, E., 218.Nelken, A., 127.Nelson, B. E., 170.Nelson, J. M., 232.Nelson, 0. A., 173.Ngmec, A., 232, 233.Neuberg, C., 229, 230.Neuburger, M. C., 288.Neuhausen, B. S., 45.Neumann, L., 128.Newman, F. H., 40.Netz, A,, 143.Nicholas, H. O., 27.Nicholson, J. W., 275.Nickelson, S. A., 73.Nickols, L. C., 72.OF AUTHORS’ NAMES.Nicolai, F., 178.Nicolet, B. H., 100.Nierenstein, M., 146, 211.Niewiazski, S., 53.Noble, 197.Noddack, W., 43.Nodder, C. R., 76.NordefeldL, E., 232.Norris, F. W., 226.Norris, (Miss) M. IT., 28.Nostitz, A. von, 207.Noyes, W. A., 102.Oblata, J., 17.Oda, K., 60.Oddo, B., G5.Oddo, G., 271.O d h , S., 205, 210.Oeconomides, 136.Oesterle, 0. A..130.Offner, M., 61.Ohmann, O., 62.Oliveri-Mandala, E., 144.Olivier, S. C. J., 98.Olmstead, L. B., 41.Olsen, C., 216.Olsson, U., 231.Ono, K., 140.Oparin, A., 223.Oppenheimer, G., 231.Ortner, K., 56.Orton, K. J. P., 101.Osborne, T. B., 228.Osterhout, W. J. V., 223.Ostertag, R., 227.Otsuka, I., 232.Oxley, A. E., 33.OSt,, €I., 82.Pacicllo, A., 48.Page, H. J., 205.Palache, C., 264.Palmer, A. W., 157.Palmer, L. S., 193.Paneth, F., 26, 51, 166.Papish, J., 50, 164.Pappenheimer, A. M., 200.Park, E. A., 199.Parker, F. W., 211.Parker, T., 217.Parker, W. L., 167, 168.Parnas, J., 87.Parsons, L. W., 35, 272.Partington, 3. R., 4, 15, 51, 271.Pascal, P., 33.Paton, 198.Patterson, J., 78.Pauli, O., 256.Pauly, H., 79, 88.Payman, W., 20.Pease, R.N., 38, 263.29298 I N D ~ X OY AUTHORS’ NAMES.Peiser, E., 186.Pennycuick, S. W., 76.Perha, G., 48.Perkin, A. G., 120, 122, 145, 226.Perkin, W. H., 77, 92, 93, 117, 120,144, 159.Perman, E. P., 59.Perren, E. A., 71, LIZ, 112.Perrin, J., 22.Peterson, W. H., 230, 231.Peto, R. H. K., 53.Petzold, A., 151.Peyl, B., 170.Peytral, (Mlle) E., 69.Pfannkuch, E., 91.Pfanstiel, R., 19.Pfeiffer, P., 147.Pfitzinger, W., 161.Philipp, K., 280.Philippe, L., 156.Phragmen, G., 255.Piccard, A., 287, 288.Pichard, G., 217, 224.Pictet, A,, 66, 80.Pieroni, A,, 139.Pilling, N. B., 45.Pinkard, F. W., 42, 55.Piwowarsky, E., 46.Plagge, H., 230.Plantefol, L., 230.Plauson, H., 62.Plimmer, R.H. A., 185, 201.Plotnikow, J., 24, 63.Poirot, G., 173.Pondal, M., 225.Ponder, A. O., 278.Ponndorf, W., 137.Pool, E., 141.Poole, 277.Pope, (Sir) ’VV. J., 73, 149, 155.Popper, E., 104.Porter, A. TV., 26.Posnjak, E., 59, 256, 257, 258.Potter, R. S., 141.Pound, J-. R., 55.Powell, W. J., 71, 112.Power, F. B., 227.Power, W. L., 211.Prandtl, W., 49.Pratt, D. D., 144.Preti, M., 231.Priestley, J. H., 224, 225.Pryde, J., 80, 195.Purnmerer, R., 95.Purrmann, L., 146.Putochin, N. J., 138.Pyman, F. L., 137, 142, 143.Quisumbing, F. A., 1‘73.Rabe, P., 157, 158.Rabinovich, A. G., 43.Racke, F., 231.Raczkowski, H., 206.Rakshit, J. K., 174.Raman, C. V., 1, 262.Ramm, (Miss) M., loti.Randall, M., 18.Rankine, A.O., 6 , 6, 263.Raske, 185.Rast, L. E., 216.Rathsam, G., 123.Rauchenberger, J., 40.Ravenna, C., 223.RBy, P., 57.Ray, R. C., 47.Read, J., 66, lG8.Rechenbcrg, C. von, 10.Rcddelien, G., 139.Redfern, G. If., 223.lteedy, J. H., 44.Reid, R. D., 52.Reif, G., 170.Reilly, A. A. B., 68.Reimer, F. C., 215.Reinfurth, E., 230.Reis, A., 147.Reis, H., 141.Reis, V. van der, 230.Reissart, A., 141.Retze, E., 123.Reyschkewitsch, E., 49.R.hym, A. J. van, 27.Richards, T. W., 42.Richmond, H. D., 170.Rideal, E. K., 60.Ridgell, R. H., 168.Riesenfeld, E. H., 54.Riffart, H., 169.Riley, G. C., 92.Ripert, J., 229.Rippel, A., 218.Risseghem, 62.Ritter, H., 140.Rivalland, C., 67.Riviere, G., 217, 224.Robertson, T.B., 202.Robinson, C. S., 215.Robinson, E., 77.Robinson, G. C., 230.Robinson, G. M., 130.Robinson, G. W., 168.Robinson, R., 30, 60, 88, 91, 98,129, 130, 139, 144, 145, 154, 159.Robinson, R. H., 217.Robinson, W. O., 210.Robison, R., 187, 189.Roder, H., 162.Rbhm, O., 58.Rbssler, O., 210.Rogers, G. S., 39.Rogozinski, F., 226.Rojahn, C. A., 70, 134, 136, 142.Rolf, I. P., 202INDEX OF AUTHORS’ NAMES. 299Itolla, L., 17.Rolt, J. W. J., 91.Rosedale, J. L., 185, 201.Rosenblatt, M., 225.Rosenheim, A:, 47.Rosenmund, K. W., 68, 91.Rosenthaler, L., 76, 170, 178,Rost, C. O., 209.Rothenburg, R. von, 134.Roy, G., 106.Rudolfs, W., 210, 214, 215.Ruff, O., 45.Russell, (Sir) E. J., 217, 218.Rutherford, (Sir) E., 278, 286.Ruzicka, L., 118.Sabalitschka, T., 79.Sako, S., 126.Salisbury, E.J., 216.Sallmann, R., 131.Salmon, C. S., 28.Samdahl, B., 272.Sandberg, M., 230.Sando, C. E., 227.Sandon, H., 218.Sandoz, M., 92.Sanfourche, A., 53.Sarkar, P. V., 57.Sasaki, T., 232.Sauerwald, F., 49.Saunders, H. L., 52.Saville, W. B., 151.Sborowsky, I., 169.Sborowsky, M., 169.Scagliarini, G., 42.Scarborough, H. A., 20.Scatchard, G., 18.Schaaf, F., 123.Schafer, 112.Schaller, W. T., 264.Schaum, K., 12.Scheibe, G., 152.Scheibler, H., 70.Schenker, R., 233.Schemer, P., 14, 258.Schetelig, J., 264.Scheucher, H., 175.Schibbe, G., 17.Schimper, 220.Schlatter, G., 230.Schlenk, W., 104.Schlubach, H. H., 42.Schlundt, 286.Schmidt, E.G., 231.Schmidt, F., 127, 144.Schmidt, G., 152.Schmidt-Hebbel, E., 51.Schneider, W., 94.Schnelle, K., 138.Scholler, W., 25, 43.Schoen, M., 229.Schonberg, A., 109.232.Schoep, A., 263.Scholl, R., 95.Scholtz, M., 126.Schonland, 283.Schrader, F., 43.Schrader, H., 204.Schreiner, E., 17.Schroeder, H., 219.Schroeter, G., 108.Schryver, S. B., 184, 226.Schultheiss, A., 128.Schulze, E., 156.Schumacher, E., 227.Schuster, K., 106.Schwab, G. M., 54.Schwarzenberg, K., 160.Schwarzer, G., 95.Schwen, G., 73.Scott, A. F., 34, 273.Scott, E. K., 262.Scott, E. L., 196.Scott, J., 91.Scott, w. w., 180.Sears, 0. H., 217.Seefried, H., 104.Seeliger, R., 27.Seeman, J., 128, 151.Seer, C., 95.Seidel, C.F., 118.Senderens, J. B., 91.Senseman, C. E., 173.Settle, R. H., 20.Shannon, M. I., 83.Sharp, P. F., 180.Sheaff, H. M., 167.Shearer, G., 235, 238.Shecld, 0. M., 216.Sheehy, J., 192.Sheldon, W., 70.Shenefield, S. L., 55.Shenstone, A. G., 282, 286.Sherman, H. C., 231.Shimomura, 74.Shipley, P. G., 199.Shoesmith, J. B., 99.Shull, C. A., 223.Siegbahn, M., 253.Siegfried, M., 184.Sielre, F., 232.Silber, H., 138.Silberrad, O., 48, 02.Silberstein, L., 1.Simmonds, N., 199.Simon, L. J., 172.Simons, H. L., 168.Simonsen, J. L., 117.Sims, H. S., 201.Sindlinger, F., 169.Skaupy, F., 277.Skraup, S., 106, 129.Skraup, %. H., 186.Slater, 281.Smekal, 285300 INDEX OF AUTHORS' NAMES.Smirnov, A. I?., 13'3, 148.Smith, A., 10.Smith, C.J., 5, 30, 263.Smith, C. L. A., 184.Smith, C. M., 179.Smith, E. F., 34, 57.Smith, E. S., 224.Smith, G. F., 45.Smith, H. H., 199.Smith, I. A., 76, 124.Smith, J. L. B., 156.Smith, L. I., 70.Smith, N. H., 51.Smith, T., 192.Smith, W., 195.Smithells, C. J., 57.Smits, A., 36.Smitt, N. K., 173.Smythe, W. R., 57.Soddy, F., 273.Sokol, R., 206.Soma, S., 208.Somogyi, R., 230.Sondheimer, A., 133, 134.Souza, D. H. de, 195.Spath, E., 156, 162, 163, 229.Speakman, J. B., 148.Spencer, G. D., 122.Speyer, E., 158.Spiegel, L., 233.Spurway, C. H., 213.Stauble, G., 91.Stahel, 288.Stark, H., 88.Starkey, E. B., 207.Starling, 196.Stateczny, V., 56.Staub, P., 156.Staudinger, H., 63, 85, 123, 124.Stavritch, K.N., 146.Steabben, D. B., 230.Steel, T., 227.Steele, E. S., 83.Steenbock, H., 201.Steibelt, W., 231.Steiner, J,, 92.Steinkopf, W., 73, 137.Steinmann, C., 141.Stephen, H., 129.Stephenson, M., 233.Stepp, W., 173.Stern, E., 227.Stern, L., 191.Steudel, H., 186.Stevenson, A., 110, 127.Steward, C. R., 171.Stewart, A. W., 284.Stewart, J., 224.Stewart, L. M., 55.Stiles, W., 224.Stix, W., 108.Stoklasa, J., 223, 224.Stoll, P., 258.Stolle, R., 143.Stolz, F., 134.Stoop, F., 185.Straus, F., 106.Strong, R. K., 287.Struwe, F., 84.Suchting, H., 208.Sullivan, F. W. jm., 104.Suntheimer, H., 141.Suschnig, E., 44.Susuki, S., 184.Suydam, J. R., 61.Svanberg, O., 231.Tadokoro, J., 165.Takeda, J., 141.Takegami, S., 45.Tamma, V.S., 262.Tammann, G., 44, 46.Ta,ni, M., 34.Tartar, H. V., 215.Taylor, F. E., 230.Taylor, H. S., 38.Taylor, J. K., 222.Taylor, T. W. J., 23.Terroine, E. E., 231.Thielepape, E., 152.Tholin, T., 230.Thomas, A. W., 173.Thomas, B., 226.Thomas, K., 187.Thomas, P., 175.Thomas, V., 62.Thompson, G. P., 273.Thomson, (Sir) J. J., 30, 31, 39.Thorpe, J. F., 71, 74, 90, 101, 110,111, 112, 114, 115, 126, 133.Thunberg, 'I?., 191.Tideswell, F. V., 205.Tingle, A., 83.Tischenko, von, 62.Titley, A. F., 117,Tobler, R., 131.Tocher, J. F., 169.Tochinai, Y., 231.Toda, S., 47.Todd, G. W., 3.Tomita, M., 229.Topley, R., 24.Torelli, G., 42.Traetta-Mosca, F., 231.Traube, I., 37, 126.Traubenberg, H. R.von, 280.Tram, O., 65.Trautz, M., 61.Travers, O., 47.Traxler, R. N., 43.Treadwell, W. D., 177, 181,Troger, J., 160.Triimpler, G., 17.Truffaut, G., 208.Tschelnitz, E., 156INDEX OF AUTHORS’ NAMES. 301Tsehenscher, F., 130.Tubandt, C., 16, 17, 43.Turina, B., 224.Tutin, H., 160.Tutton, A. E. H., 251, 259.lrnger, L., 198.Ungerer, E., 206.Unno, T., 140.Urbain, G., 49, 52.Urbain, P., 49.Usherwood, E. H., 3, 4, 69.Uyeda, Y., 226.Vegard, L., 258.Vereinigte Chemische JVerke, Akt,.-Vergelot, C., 226.Vernadsky, W. J., 205.Vesterburg, K. A., 214.Viehoever, A., 227.Vilbrandt, F. C., 55.Vilmorin, J. do, 233.Vincent, V., 213.Visco, S., 228.Vogel, 223.Voicu, J., 208.Voigt, A., 54.Vollbrecht, E., 226, 232.Vorlander, D., 12.Vortmann, G., 174.Vorwerk, W., 26.Vosburgh, W.C., 232.Vossen, G., 108.VotocGk, E., 172.Ges., 229.JVaage, 219.Wagner, J., 177.Wagner, O., 158.Wagner, W., 6G.Wahl, O., 161.Wakeman, J., 228.Waksman, S. A., 209, 213.Walbum, L. E., 230.Walker, F., 231.Walker, H., 195.Walker, N., 74.Wallace, T., 42.Wallis, A. E., 50.Wann, F. B., 208, 222.Warburg, O., 191, 218.Ward, C. F., 70.Wardlaw, W., 42, 55.Wasastjerna, J. A., 16.Waters, C. A., 180.Watson, A. F., 170.Watson, F., 193.Wattenberg, H., 181.Wayman, M., 231.Weber, E., 223.Wedekind, E., 57.Wegscheider, R., 8.Wehmer, C., 225.Weigert, F., 25, 43.Weil, K., 80.Weimer, J. H., 232.Weinberg, A. A., 165.Weiser, H. R., 27.TVciss, A., 112.Weiss, S., 194.Weissberger, R., 155.Weitz, E., 151.Wells, H. G., 102.Wells, H. L., 44.Weltzien, ITT., 106.Wendt, G. L., 38, 30, 40, 280.Werner, A., 281.Werner, E. A., 8-2.Wertheim, E., 170, 232.Wester, D. H., 225, 233.Wsstgren, A., 255.Wheeler, R. V., 20, 205.Wheeler, T. R., G5.TYhotham, &I. D., 233.White, A. G., 21, 3;.White, E. C., 167.Whitney, M., 205.Wibaut, J. P., 40, 50, 61.Wick, (Miss) F. G., 257.Widmer, C., 121.Wieland, H., 94, 104.Wiessmann, H., 215.Wijs, 19.Wilkes, S. H., 59.Willard, H. H., 45, 177.Williams, A. G., 173.Williams. A. W., 25.Williams, J.. 68.Willstattcr, R., 87, 160, 231.Wimberger, H., 199.Windaus, A., 80, 143.Windaus, W., 116.Winkler, K., 61.Winter, 1,. R., 195.Winter, 0. B., 215.Winterstein, E., 156, 280.Wiswald, J., 53.Withrow, J. R., 55.Wittelsbach, W., 82.Witzemann, 194.Wober, A., 178.Wohler, L., 46.Wohl, A., 6, 7, 8, 117.Wojniez-Sianozencki, 61.Wolf, 277.Wolff, P., 156.Wood, A. B., 286.Wood, R. W., 2, 24, 40.Woodman, H. E., 228, 230.Woodward, J., 215.Wormser, M., 44.Wouseng, S., 66.Wood, J . K., 51302 INDEX OF AUTHORS’ NAMES.Wrangell, M. von, 215.Wren, H., 76.Wright, D., 206.Wright, E., 75.Wulf, 0. R., 53, 55.Wurmser, R., 231.Wuyts, H., 74.Wyckoff, R. W. G., 236, 252, 256.257, 258, 269, 280.Yabuta, T., 230.Yoder, L., 146.Zanetti, 61.Zeckendorf, K., 229.Zerweck, W., 138.Zetzsche, F., 68, 91.Ziegler, K., 106.Ziegner, H., 70.Zijp, C. van, 171.Zilva, S. S., 199, 200.Zintl, E., 181.Zucker, T. F., 200

ISSN:0365-6217    

DOI:10.1039/AR9221900289

出版商:RSC    

年代:1922

数据来源: RSC

摘要:

INDEX OF SUBJECTSAcetaldehyde, synthesis of, 67.Acetanilide, distinction betweenAcetic acid, esters, velocity ofAcetoacetic acid, ethyl ester, mechan-Acetobromoamine, bromination with,Acetone, pyrogenic decomposition3-Acetoxy-2 : 4-dimethoxyacetophen-Acetylene, hydrogenation of, 60.synthesis of acetaldehyde andAcetylenic glycols, preparation of, 66.Acetylisovanillone, synthesis of, 94.Acids, determination of configurationof, by the boric acid method, 71.estimation of, 173.phenacetin and, 171.hydrolysis of, 19.ism of syntheses with, 70.101.of, 69.one, synthesis of, 94.acetic acid from, 67.enolisation of, 123.aliphatic, bromination of, 69.Acid chlorides, reduction of, 68.Actinium, 287.Adsorption, 27.Agricultural analysis, 168.Alcohols, 64.Aldehydes, 67.modified Schiff’s reagent for, 170.estimation of, 172.A l p , marine, arsenic in, 226.Alkali halides, crystal structure of,Alkaloids, 156.256.cactus, 161.calumba root, 162.cinchona, 157.in plants, 223, 229.estimation of, 173.Alkylation, 93.Alkylpyrazoles, 136.Aluminioxalic acid, potassium salt,crystallography of, 262.Aluminium arsenide, 54.chlorosulphoxide, 48.hydroxide, crystalline, 47.selenide, 55.sulphur chloride, 48, 92.separation of, from iron, 179.Amino-acids, degradation of, 232.from proteins, 183.Ammonia, synthesis of, 52.41.37.absorption of, by lithium nitrate,effect of drying on the reactivity of,hydrogen fluoride, 57.chloroplatinate, crystal structurefluosilicate, crystal structure of,nitrate, decomposition of, 62.Amygdalin, structure and methyl-isoAmyl alcohol, preparation of, 65.Analysis, agricultural, 168.electrochemical, 180.gas, 166.inorgamc, 174.microchemical, 174.organic, 169.physical, 164.from, 117.Ammonium, preparation of, 42.of, 258.259.ation of, 79.Andropogon Jwarancusa, A4-careneAnhalamine, synthesis of, 162.Anhaline, constitution of, 161.Anhydroecgonine, constitution of,+-Aniline, preparation of, 144.Anthocyanidin pigments, constitu-Anthocyanins, 227.Anthracene, density and molecularAnthraquinone, estimation of, 173.Anthraquinones, compounds of boricAntimony, isotopes of, 269.sulphide, estimation of, 178.estimation of, in copper, 178.Apophyllenic acid, and its deriv-Apples, pectic constituents of, 219.Aragonite minerals, crystal structureArginine, estimation of, 185.Arsenic, modifications of, 54.160.tion of, 145.structure of, 242.acid with, 121.atives, 147.of, 257.alloys with zinc, 46.30304 INDEX OF SUBJECTS.Arsenic sulphide, estimation of, 178.Arsenic acid, estimation of, 178.Arsenates, sterilisation of soil by,Arsenites, sterilisation of soil by,detection of, 175.estimation of, 179.separation of, 179.217.217.Aspartic acid, hydroxy-, from hydro-lysis of proteins, 186.Asymmetric syntheses, 75.Atoms, structure of, 31, 32, 279, 284.models of, 284.function of the outer electrons of,induced alternate polarity of, 30.Atomic theory, 30.weights, 33.Butoxidation, 69.Azelaic acid, synthesis of, 73.Azenes, 85.249.constancy of, 272.Bacillus, nitrogen-fixing, 208.Barium cyanide, preparation of, 46.Beckmann rearrangement, 95.Becquerelite, 263.Benzaldehyde, copper compound of,Benzanthrone, preparation and con-Benzene, constitution of, 86.selenic acid, 46.sulphuric acid, 46.123.stitution of, 122.derivatives, orientation of, 90.estimation of, 167.Benzil dioximes, formulae of, 95.Bends, tautomerism of, 109.Benzoic acid, crystal unit cell of,Benzophenone-2 : 4 : 2’ : 4’-tetracarb-oxylic acid, keto -dilactone, resolu-tion df, 76.Henzoxazole derivatives, fluorescenceof, 141.Benzoxazoles, substituted, hydrolysisof, 129.Benzoyl- 5-quindoline, o-amino-, 155.Benzyl chlorides, substituted, hydro-Betaines, 147.Bishydrocarbostyril-3 : 3’-spiran, 152.Bismuth subiodide, 54.Blood, sugars in, 195.Boiling points, abnormal, 11, 35.Boron, atomic weight of, 34.Boric acid, compounds of anthra-quinones with, 121.Borates, complex, 47.Bread, proteins of, 189.240.m-chloro-, preparation of, 92.lysis of, 98.Butadiene, preparation of, 61.cycZoButanone and its derivatives,isoButyl alcohol, preparation of, 65.116.Cactus alkaloids, constitut,ion of,Cadalene, constitution of, 118.Cadmium, use of, as a reducing agent,177.alloys with magnesium, 46.with mercury, use of, in analysis,iodide, crystal structure of, 257.Caesium chloride as a reagent inmicrochemical analysis, 174.halides, crystal structure of, 257.Caffeine, estimation of, 174.Calcium, metallic, properties of, 46.isotopes of, 268.metabolism of, 198.alloys with mercury, preparationof, 45.chlorite, 57.161.177.Calcium-ammonium, 46.Calumba root, alkaloids from, 162.a-Campholytic acid, tautomerism of,Camphor from campholenic acid, 107.Caoutchouc, hydrogenation of, 63.Carbohydrates, 77.fermentation of, 229.detection of, 170.Carbon, fusion of, 49.114.dioxide, assimdation of, by plants,218.estimation of, in organic com-A3- and A*-Carene, 117.Carnitine, structure and reactions of,Caseinogen, hydrolysis of, 187.Catechin, constitution of, 146.Cathodes, silver, use of, 180.Celloisobiose, 82.Cells, electrochemical standard, 17.Cellulose, constitution of, 81.Cerebronic acid, constitution of, 72.Ceruleofibrite, 264.Chelidonic acid, action of amineswith, 148.Chitin, constitution of, 139.Chlorine, activation of, by light, 38.estimation of, 172, 176.Chlorites, 57.Chlorohydrins, preparation of, 66.isochondodendrine, constitution of,Chromium trioxide, solubility of, inestimation of, in nickel-chromiumpounds, 172.147.163.sulphuric acid, 56.steel, 176INDEX OF SUBJECTS.306Chrysophanic acid, synthesis andCinchona alkaloids, constitution of,Cinchonic acid, synthesis of, 151.Clupeine, hydrolysis of, 1 S6.Coagulation by ions, 27.Coal gas, estimation of sulphurcompounds in, 168.Cobalt carbonyls, 50.fluoride, ammines of, 59.Cod-liver oil, treatment of ricketsColloidal solutions, 25.Colloids, protective, 27.Colostrum, significance of, 192.Columbium, separation of, fromtantalum, 179.Condensations, 93.Copper, reflection of &-rays of, fromalkali sulphates, hydrated, 42, 260.oxides, 42.sulphides, 42.compound of benzaldehyde, 123.Cupric tetrammine nitrate andCuprous chloride, reaction of sul-halides, crystal structure of, 257.detection of, 175.estimation of, 176, 17s.estimation of antimony in, 178.Corundum, crystal molecule of, 243.Corydaline, formula of, 163.Crystal unit, 236.Crystals, structure of, 12, 235, 261.constitution of, 121.157.with, 198.calcite, 263.nitrite, 43.phur dioxide with, 55.by means of X-rays, 237, 251,size of atoms in, 263.determination of the density of, byX-rays, 241.biaxial, new optical property of,262.strained, X-radiograms of, 259.265.Crystallisation of liquids, 12.Crystallography, books on, 264.+-Cumene, preparation of, 96.Cyanines, 153.thio-, 154.isocyanines, thio-, 164.Cyanogen :-Hydrocyanic acid, structure andgaseous, tautomeric equilibriumCyaphenines, formation of, 131.Cyclic compounds containing nitro-gen, stability of, 127.Cystine, hydrolysis of, 186.synthesis of, 69.of, 4.Density, limiting, of gases, 6.Dewindtite, 263.Dextrose in blood, 195.acetone derivatives of, 78.Diabetes, 193.Diacetyldihydrodipyridyl, 150.Diacetyltetrahydrodipyridyl, 150.Diazo-compounds, aliphatic, reactionsof, s5.Dibenzothianthrene, 6 : 7 : 12 : 14-tetrah ydroxy - , 13 2.4 : 4’-Dibenzyloxybenzil, tautomer-ism of, 109.Dicarboxyglutaconic acid, ethylester, action of piperidine with,112.Diethyl sulphide, BB’-dichloro-, form -ation and derivatives of, 73.Digitonin, constitution of, 80.Dihydrocampholenic acids, 108.Dihydroisoindole, preparation of, 127.3 : 4-Dihydro-l : 2-naphthacridine-14-N-Dimethylalaninol, 84.2 - p -DimethylaminostyrylpyridineBB-Dimethglbutane, 61.Dinaphthathiophendiquinone, 132.y-Diphenic acid, 6 : 6‘-dinitro-, reso-lution of, 89.Diphenylacetic acid, and its ethylester, potassium derivatives, 124.Diphenyl, amino-, synthesis of, 95.Diphenyl-a- and -B-naphthylmethyls,103.Dipropyl ketone, formation of, G O .Dipyridyl violet chloride, constitu-Dipyrrole, hydroxy-, 139.Di-2-quinolyl ketone, 152.Disaccharides, 79.Dithionates, estimation of, li’i.Dopplerite, 205.Drying, effect of, on physical andcarboxylic acid, 155.methiodide as a photographic sen-sitiser, 149.Dimethyldihydroresorcinol, di-bromo-, bromination with, 101.tion of, 150.chemical properties, 36.Earths, rare, densities of the oxidesof, and their separation, 49.Electrical conductivity, 16.Electrochemical analysis, 180.Electrodes, potential of, 17.Electrolytes, ionisation of, 15.Elements, periodic systems of, 27 1.iodine, use of, 180.isotopic constitution of, 267.crystalline, structure of, 255..light, disintegration of, by a -particles, 278.Elsholtzic acid, constitution of, 137.Emulsin, 231, 232306 INDEX OF SUBJECTS.Enzymes, chemistry of, 231.dl-Epicatechin, preparation of, 146.Equation of condition, 7.Esters, velocity of saponification of,Ethylene, hydrogenation of, 60.Ethyl ether, atmospheric oxidationof, 67.Eudalene, 118.20.Ferment a t ion, 22 9.Ferric oxide.See under Iron.Ferrioxalic acid, potassium salt,crystallography of, 262.Ferrocyanides, titration with, 181.Fertilisers, amount of, in relation t ocrop yield, 218.estimation of nitrogen in, 169.Fluocerite, 58.Fluorescence, 24.Fluorine, spectrum of, 57.181.Hydrofluosilicic acid, estimation of,detection of, 175.combination of hydrogen phos-phide with, 67.detection of, 170.Formhydroxamic acid, formation of,Formic. acid, thermal decompositionFriedel-Crafts’ reaction, 94.d-Fructose.$ee Laevulose.Fulminic acid, mercuric salt, dc-composition of, 39.Formaldehyde, synthesis of, 64.in plants, 220.of, 24.Gallaldehyde, preparation of, 91.Gamboge suspensions, 26.Gas analysis, 166.Gases, molecular structure of, 5.specific heats of, 2.limiting. density of, 6.viscosity of, 5.ignition of, 20.inert, 39.Germanium, crystal structure of, 255.compounds, 50.Gillespite, 263.Glucinum, atomic weight of, 33.crystal structure of, 255.hydroxide, 44.oxide, crystal structure of, 256.sulphates, 45.Glucosamine, 78.d-Glucose. See Dextrose.Glucosides, 79.Glutaconic acids, isomerism of, 72.Glutathione, 189.Glycerol, preparation of, by fer-mentation, 229.Glycerol, synthesis of, 66.bromo- and chloro-hydrins, 66.Glyoxalines, 5-nitro-, reduction of,Gold, colloidal, estimation of, 178.alkali chlorides, complex, 44.sulphides, 44.Grapes, Spanish, fluorine in, 225.Grignard reactions with hydrocar-bons, 62.Guanidine derivatives, synthesis of,84.142.estimation of, 169.isoHaematein tetramethyl etherHalogen atoms, lability of, in organicreactivity of, in organic com-ferrichloride, 145.compounds, 74.pounds, 98.Halogenation, 02.Harmaline, constitution of, 159.Harmine, constitution of, 159.Heat, specific, of gases, 2.Helium from explosion of tungstenwires, 39.spectra of, 1.solubility of, 39.Hexadecanesulphonic acid, colloidalproperties of, 28.Hexahydrodioxydiboron, potassiumsalt, 47.Hexamethyleneimine, 127.Hexoses, oxidation of, 77.Humic acid, origin and nature of,Humoceric acid, 72.Hydrazine, estimation of, in presenceof hydroxylamine, 177.Hydrazo - compounds, isomericchanges of, 97.Rydrazodicarbonthiocarbonamides,reactions of, 130.Hydrocarbons, 60.aromatic, action of nitrogen tri-chloride with, 102.Hydrocyanic acid.See under Cyano-gen.Hydrofluosilicic acid. See underFluorine.Hydrogen, active, preparation andproperties of, 39.activation of, by palladium orplatinum, 38.atoms, diameter of, 264.ions, determination of the concen-tration of, 175, 180.nuclei, collisions between a-particles and, 281.spectra of, 1.specific heat of, 3.peroxide, pure, properties of, 41.204INDEX OF SUBJECTS. 307Hydrogen phosphide, estimation of166.selenide, 66.telluride, 56.estimation of, 166, 172.y- and 6-Hydroxy-aldehydesY syn.thesis of.78.y- and 6-Hydroxy-ketones, synthesiEof, 78.Hydroxylamine, crystalline, prepar-estimation of, in presence ofHypophosphorous acid. See underI-Iyssopin, 120.Hyzone, 40.ation of, 52.hydrazine, 17 7.Phosphorus.Ice, crystal structure of, 254.Ignition of mixed gases, 20.Imino-oxazolidines, 141.Iminothiodiazolone, 130.Indazoles, isomerism of, 132.Indenoindoles, synthesis of, 130.Indenoquinolines, 154.Indicators, 175.Indole, synthesis of, 139.Inorganic analysis, 174.Insulin, 196.Inulin, constitution of, 83.fermentation of, 230.Invertase, 23 1.Iodine electrodes. See Electrodes.Ionisation of electrolytes, 15.Iron, crystal structure of, 255.isotopes of, 268.olectrolytic, solubility of, in sulph-uric acid, 58.fusion of sodium hydroxide with, 42.pentacarbonyl, 49.Ferric oxide, hydrates and sulphatesSteel, estimation of manganese andestimation of phosphorus in,of, 58.vanadium in, 178.178.isoIsatogens, 135.Isatoids, 135.Isobares, 270.Isomerism, 132.Isoprene, attachment of addenda to,Isotopes, 2G7.63.periodic systems of, 271,table of, 270.atomic volume of, 273.spectra of, 273.separation of, 276.Kephalin, 202.Ketenacetal, ‘70.Ketens, reactions of, 85.a-Ketocampholenic acid, 107.a-Keto-138-diethylglutaric acid, 11 1.a-Ketoglutaric acids, tautomerism of,111.Ketones, 67.Krypton, estimation of, 39.Lac, Burmese, constituents of, 120.Indo-Chinese, constituents of, 1 19.Japanese, constituents of, 119.estimation of, 172.“ Laccol,” 119.Lactase, 231.8-Lactones, formation and propertiesof, 72.Laevulose, acetone derivatives of, 78.Lanthanum, atomic weight of, 34.Laudanine, synthesis and formula of,Lead isotopes, band spectra of, 275.detection of, 171.163.series spectra of, 273.separation of, 277.alloy with strontium, 46.oxides, 51.Lecithins, 201.Light, ultra-violet, effect of, onLipase, 232.Lipoids, 201.Liquids, abnormal boiling points of,11.rickets, 199.vapour pressure of, 8.crystallisation of, 1 1.Lithium isotopes, series spectra of,274.chlorite, 57.fluoride, X-ray analysis of, 14.hydride, crystal structure of, 256.structure and stability of, 41.nitrate as an absorbent for am-monia, 41.Liver oils, colour reaction of, withsulphuric acid, 170.Lucerne hay as a diet for milkingcows, 201.Magnesium alloys with cadmium, 46.with mercury, 45.perchlorate, 45.oxide, crystal structure of, 266.detcction of, 175.Malt, proteolytic enzymes of, 232.Maltase, 231.Mammary glands, secretion of, 192.I-Mandelamide, racemisation of, withdl-Mandelic acid, resolution of, 74.Manganese, estimation of, 178, 179.Meconif acid, estimation of, inopium, 174.Melanovanadite, 264.alkali, 76308 INDEX OF SUBJECTS.Melting points, abnormal, of solidsMercurialis perennis, carbohydratesMercury, purification of, 46.isotopes of, 276.vapour, fluorescence of, 2.oxychlorides, 47.Metallic nitrates, isomorphous, crys-tal structure of, 258.Metals, separation of, without use ofhydrogen sulphide, 174.Methane, synthesis of the polyaceticacids of, 72.Methoxybenzyl bromides, hydrolysisof, 99.6 -Met hox yin dole - 2 - carb ox y dime t hyl-ace talylme thylamide, in tramole -cular condensation of, 128.Me thoxylcetomethyldihydrocarboline,128.Me thoxyketomethyldihydroindoledi-azine, 128.Methyl alcohol, synthesis of, 64.bromide, preparation of, 73.Methylal, dibromo-, 73.Methylenecyclopropane, 10 7.B -Methylglutaconic acid, a-cyano -,ethyl ester, addition of hydro-cyanic acid to, 70.5-Methylglyoxaline, 4-nitro -, 13 7.Methyl-n-hexylcarbinol, resolution of,a-Methylmannoside, synthesis of, 80.y-Methyl-Ay-pentenes, isomeric, sep-1 -Me thylcyclopropane- 1 -carboxylicMe thylisopropylcoumaranono, syn -Mezcaline, constitution of, 161.Michael condensation, reversibilityMicrochemical analysis, 174.Microspira desulphuricans in soil, 209.Milk, fat of, 192.after drying, 37.in leaves of, 219.75.arat'ion of, 62.acid, 106.thesis of, 129.of the, 71.proteins of, 189.vitamins in, 193.Minerals, effect of micro-organismson the decomposition of, 205.Molecules, crystalline condition of,234.Molybdenum carbonyl, 49.separation of, from tungsten, 179.Monosaccharides, 77.Naphthalene, crystal unit of, 241.Naphthalenes, dihydroxy -, tauto -meric, 108.Naphthaphenthiazine, synthesis of,132.Nephelometry, 165.Nitration, 92.Nitrogen fixation in soil, 207.compounds, synthesis of, in plants,' 83.assimilation and metabolism of ,trichloride, action of aromatichydrocarbons with, 102.oxides, 53.estimation of, 167.estimation of, in fertilisers, 169.in plants, 220.Nitrosylselenic acid, 56.Nitszchia closterium, synthesis ofvitamin by, 200.0 : 3 : 3-dicycloOctane, 108.0 : 3 : 3-dicyclo-All-Octene-3 : 7-dione-2 : 4 : 6 : 8-tetracarboxylic acid,methyl ester, 108.Opium, estimation of alkaloids in,174.Orcinol, synthesis of, 87.Organic a.nalysis, 169.Osmium, detection of, 175.Osmosis in plants, 223.Oxygen, estimation of, 167, 172.Ozone, properties of, 54.Pancreas, effect of, on diabetes, 196.Paraffin wax, constituents of, 64.a-Particles, disintegration of lightelements by, 278.collisions between hydrogen nucleiand, 281.as detonators, 282.Pectinase, 232.Pentamethylbenzene, preparation of,96.cyclopentane-1 : 2 : 3-tricarboxylicacids, isomeric, 77.Pentaphenylethyl, 104.clicycZo-A2-a-Penthiophen - 5 - carboxy-Periodic systems, 271.Petroleum, polymerisation in forma-tion of ozonides from, 64.Phenacetin, distinction between acet-anilide and, 1 7 1.Phenanthrene, estimation of, 173.Phenols, detection of, 171.Phenol-red as an indicator, 175.B-Phenyl-aa-dimethylpropionic acid,preparation of, 93.B -Phenylhydroxylamine, preparationof, 92.3-Phenylindazole, isomerism of, 133.Phosphonium iodide, crystal struc-ture of, 258.Phosphorus compounds, r61e of, inthe metabolism of hexoses, 194.lie acid, ethyl ester, 137.trihydride, preparation of, 54INDEX OFPhosphorus pentoxide, purificationPhosphoric acid, estimation of, 169.Phosphates in soils, 215.Hypophosphorous acid, active formestimation of, in steel, 178.of, 53.of, 53.Photographic sensitiser, new, 149.Photosynthesis of nitrogen com-Physical analysis, 164.Physiological chemistry, books on,Picric acid, ionisation of, 16.Picrorocellin, 15 1.Pinacyanol, synthesis of, 153.Pinus longifolicl, A3-carene from, 117.Piperidine, action of ethyl dicarb-osyglutaconate with, 112.Plants, acids in, 227.pounds, 220.182.alkaloids in, 223, 229.assimilation of, 218, 220.carbohydrates in, 226.carbohydrate metabolism in, 219.chlorine in, 225.constituents of, 225.glucosides in, 226.manganese in, 225.synthesis of nitrogen compounds in,leguminous, fixation of nitrogen by,osmosis in, 223.pigments in, 225.proteins in, 228.effect of the soil solution on growthof, 214, 216.effect of colloidal silica in soil ongrowth of, 215.stimulating and toxic action ofvarious compounds on, 224.Polonium, velocity of a-rays from,282.Polysaccharicles, constitution of, 80.Potassium, crystal structure of, 255.chloroplatina te, cryst a1 structurecyanide, crystal structure of, 257.degradation of, 232.hydrolysis of, 183.metabolism of, 187.new base from, 186.sulphur constituents of, 184.83.222.of, 258.Propylene, preparation of, 61.Proteins, biological value of, 187.Protons, 279.Pyrazoles, electrochemical oxidationPyrazolone series, isomerism in the,Pyrene, synthesis of, 123.Pyridine, detection of, 171.of, 142.134.separation of, from coal tar oil, 148.SUBJECTS .309Pyridinium nitrate, use of, in nitra-y-Pyridones, structure of, 148.Pyrimidine derivatives, 146.Pyrofulmin, 85.Pyrogallol solutions, 166.Pyrrole, catalytic reduct,ion of, 138.Pyrylium salts, synthesis of, 144.tion, 92.Quartz, crystalline symmetry of, 243.Quinol, relation between quinoneQuinoline derivatives, 15 1.isoQuinoline, separation of, from coaltar quinoline, 155.and, 86.Racemic compounds, optical activa-tion of, 74.Radiation theory, 22.Radioactive indicators, 26, 165.Radium-B, p-rays from y-rays of, 284.Raffinase, 231.Rapic acid, 72.Rays, positive, analysis of elements byRGntgen, intensity of reflection of,means of, 267.249.crystal analysis by means of, 13,a-Rays, luminous path of, in crystals,281.237, 251, 265.range of, in solids and liquids, 280.from polonium, velocity of, 282.&Rays, scattering of, 283.excited by a-rays of radium-B, 284.?-Rays, from the impact of a-rayson metals, 281.*, vnReduction, 91.Ricinine, constitution of, 156.Rickets, 198.Ring formation, 114, 125.Rochelle salt, piezo-electricity of, 262Rubidium bromate, 42.Ruby, crystalline structure of, 244.Rutaecarpine, constitution of, 159.Ruthenium carbonyls, 49.tetroxide, 59.Saccharase, 231.d-Saceharic acid, degradation of, 77.Saccharophosphatase, 232.Sahidin, nature of, 202.Saponins, constitution of, 80.Sativic acid, constitution of, 72.Scandium, extraction of, 49.apoScopolamine, 160.Scopoline, formula of, 160.Sebacicdialdehyde, 68.Selenates, hydrated double, crystal-lography of, 259310 INDEX OF SUBJECTS.Starch, constitution of, 8U.ISelenium, isotopes of, 268.acetylacetones, 68.dioxide, 56.oxybromide, 56.oxychloride, 5 6.Semibenzenes, transformations of, 96.Sesquiterpenes, action of heatedsulphur with, 118.Silicon, modifications of, 50.dioxide (silica), effect of, on plantgrowth, 215.Silk fibroin, hydrolysis of, 186.Silver compounds, photochemistryof, 25.bromate, 44.perchlorate, 44.halides, decomposition of, by light,molybdate, crystal structure of,oxide, crystal structure of, 256.peroxide, black, 43.43.259.Xincosite, 263.Soap solutions, 28.Soddite, 263.Sodium bromate, crystal structure of,258.chlorate, crystal structure of, 258.chloride, X-ray analysis of, 14, 31.chlorite, 57.hydroxide, fusion of metals with,metasilicate, hydrates of, 50.Soil, absorption and basic exchangeacidity of, 212, 216.colloids of, 204.flocculation of, 206.moisture in, 210.nitrogen compounds in, 207.utilisation of phosphates in, 215.solution, composition of, 210.sterilisation of, 21 7.sulphur compounds in, 209, 215.analysis of, 168.estimation of colloidal clay in,Solids, electrical conductivity in, 16.42.in, 206.206.and properties of, 51.Sucrose, velocity of hydrolysis of, 18.detection of, 170.estimation of, 173.Sugars, metabolism of, P93.in blood, 195.reducing, estimation of, 173.Sulphides, estimation of, 1'76.Xulphiformin, 67.Sulphoacetic acid, syntheses with, 93.Sulphur compounds, estimation of,dioxide, reaction of cuprous chlor-Sulphates, estimation of, 181.Sulphites, properties of, 55.in coal gas, 168.oxidation of, in soil, 209.ide with, 55.Systems, disperse, 25.chlorite, 57.detection of, 175.Q ..-- :-:#.-#.:,I " ,,:,,L,,a,,,2- "TrnTannase, 232.Tannin, detection of, 17l.Tantalum, separation of, from colum-bium, 179.Tartaric acid, structure of, 244.ethyl ester, properties of, 75.Tautomerism, 108.keto-enolic, 68.Telluric acid, 56.Tellurium, pure, 56.acetylacetones, 6 S.Teloidine, formula of, 161.Tethelin, nature of, 202.Tetrahydroacetophenonc, synthesisof, 94.Tetrazoles, formation of, 143.Tetrophane.See 3 : 4-Dihydro-1 : 2-naphthacridine-14-carboxylic acid.Thallium borates, 48.chlorite, 58.bismuth halides, 48.sulphates, complex, 45.stitution of, 73.Thapsic acid, synthesis and con-Thiobacillus, species of, in soil, 209.' * Thitsiol," 120.Thorium, estimahion of, 166.Thorium-C, emission of a-particlesby, 286.Trimethyli&propylmethane, 61.Triphenylbiphenylene &h yl, 104.m..:-L ---- l-&L:---l---- L:--l L-l--L---npectra 01 isotopes, i5 I.$.Rontgen-ray, in relation to atomicStannic acid. See under Tin.Stannous hydroxide. See under Tin.structure, 31, 32.- - . . ~ - -inorveitite, ~04.Thymine, detection of, 171.Tin, isotopes of! 268.Stannic acids, 51.Stannous hydroxide,- ~ preparation . -estimation of, 220.Stasite, 263.Steel. See under Iron.Stereoisomerism, 136.Tissues, &idation in, 189.Toluoyl chlorides, chlorination of, 92.Triethylsulphonium bromide, de-composition of, 23.lJllt5SlS u1, 0%. I 1w11 u1, LWUINDEX OF SUBJECTS. 31 1Triphenylme thyl, 103.Triphenyl- 1 : 3 - oxthiophan - 5 -one,Tripyrrole, 138.r-Tryptophan, synthesis of, 140.Tungsten, action of thoria with, 57.oxides, 57.detection of, 175.144.Ultra-atration, 28.Uranium, 287.detection of, 176.estimation of, 180.Uranium- V , 288.Uranium-2, 288.Urazole, thio-, sodium salt, 130.Urease, 233.Urushiol, 11 9.Valency of elements, 30.Vanadic acid, estimation of, 177.Vanadium, estimation of , in steel, 17s.Vapour pressure of liquids, 8.Velocity of hydrolysis, 18.Vinyl alcohol, preparation of, 66.Vinyl chloride, polymerisation of, 62.Vinylarsines, B-chloro-, 53.Vinylcyclopropane, 10 7.Vinylsulphuric acid, preparation of,Viscosity of gases, 5.Vitamins, 198.in milk, 193.61.X-rays. See Rays, Rontgen.Xanthines, formation of, 140.Xanthorocellin, 151.Xenon, isotopes of, 269.estimation of, 39.Xylenol-blue as an indicator, 175.Yeast, activation of killed, 190.Yttrium, atomic weight of, 34.Zinc, isotopes of, 268.alloys with arsenic, 46.with mercury, use of, in analysis,177, 181.Zinc-formaldehyde hyposulphite, 67

ISSN:0365-6217    

DOI:10.1039/AR9221900303

出版商:RSC    

年代:1922

数据来源: RSC