摘要:

ANNUAL REPORTSON THEPROGRESS O F CHEMISTRYANNUAL REPORTSH. BASSETT, D.Sc., Ph.D., D.-ds-Sc.E. J. BOWEN, M.A.B. A. ELLIS, M.A.E. H. FARMER, D.Sc.J. J. Fox, O.B.E., D.Sc.A. F. HALLIMOND, M.A.C. N. HINSHELWOOD, M.A., F.R.S.H. KIXG, D.Sc.ON THEG. A. R. KON, M.A., D.Sc.A. G. POLLARD, B.Sc., A.I.C.J. PRYDE, M.Sc.A. S. RUSSELL, M.C., M.A., D.Sc.N. V. SIDQWICYK, O.B.E., M.A., Sc.D.,F.R.S.J. H. WOLFENDEN, M.A.H. w. THObWSON, M.A., Ph.l).PROGRESS OF CHEMISTRYF O R 1932.ISSUED BY THE CHEMICAL SOCIETY.Carnmittee afChairman: J. C. P m ~ mH. E. ARMSTRONG, LL.D., F.R.S.G. 11. BENNETT, M.A., Ph.D.H. V. A. BRISCOE, D.Sc.H. >I. DAWSON, D.Sc., Ph.D.F. G. DONNAN, C.B.E., LL.D., F.R.S.H. W. DUDLEY, O.B.E., Ph.D., P.R.S.F. P. DUNN, B.Sc., F.I.C.A.C. G. EQERTON, M.A., F.R.S.J. J. Fox, O.B.E., D.Sc.W. E. GARNER, D.Sc., A.I.C.C. S. GIBSON, O.B.E., M.A., F.R.S.W. N. HAWORTH, D.Sc., F.R.S.I. 31. HEILBRON, D.S.O., D.Sc., P.R.S.G. a. HENDERSON, M.A., D.Sc., F.R.S.J. T. HEWITT, D.Sc., F.R.S.C. N. HINSHELWOOD, M.A., F.R.S.@bitor :CLARENCE SMITH, DSc.riB 'f$xblicafioa :O.B.E., D.Sc., F.R.S.J. KENNER, D.Sc., F.R.S.J. KENYON, D.Sc.H. KING, D.Sc.T. M. Lomy, C.B.E., D.Sc., F.R.S.W. H. MILLS, Sc.D., F.R.S.EMILE S. MOND.T. S. MOORE, M.A., B.Sc.J. R. PARTINOTON, N.B.E., D.Sc.E. K. RIDEAL, M.A., D.Sc., F.R.S.R. ROBINSON, D.Sc., F.R.S.F. M. ROWE, D.Sc., F.I.C.J. L. SIMONSEN, D.Sc., F.R.S.S. SMILES, O.B.E., D.Sc., F.R.S.S. SUQDEN, D.Sc.J. F.THORPE, C.B.E., D.Sc., F.R.S.assistrrat &;bitor :A. D. MITCHELL D.Sc.VOl. XXIX.LONDON:T H E C H E M I C A L S O C I E T Y1933PRIXTRD IN QREAT BHITAW BYBUNOAY, BUFFOLK.RICHARD OLAY & SONS, LIMITEDCONTENTS.PAGEGENERAL AND PHYSICAL CHEMISTRY. By E. J. BOWEN, M.A.,C. N. HINSHELWOOD, M.A., F.R.S., N. V. SIDQWICK, O.B.E., M.A.,Sc.D., F.R.S., H. W. THOMPSON, M.A., Ph.D., and J. H. WOLFENDEN,M.A. . . . . . . . . . . . 13INORGANIC CHEMISTRY. By H. BASSETT, D.Sc.. Ph.D., D.-6s.-Sc. . 74ORGANIC CHEMISTRY :-Part I.-ALIPHATIO DIVISION. By E. H. FARMER, D.Sc. . . . 96-Part II.-HOIOCYCLIC DIVISION. By G. A. R. KON, M.A., D.Sc. . 136-Part III.-HETEROCYCLIC DIVISION. By H. KING, D.Sc. . . . 175.ANALYTICAL CHEMISTRY. By J. J. Fox, O.B.E., D.Sc., and B.A.ELLIS, M.A. . . . . . . . . . . 220BIOCHEMISTRY. By A. G. POLLARD, B.Sc., A.I.C., and J. PRYDE, M.Sc. 239GEOCHEMISTRY (1931-32). By A. F. HALLIMOND, M.A. . . . 275A. S. RUSSELL, M.C., M.A., D.Sc. . . . . . . 299RADIOACTIVITY AND SUB-ATOMIC PHENOMENA (1931-32). BTABLE OF ABBREVIATIONS EMPLOYED I N THEAbbreviated Title. FULL TITLE.REFERENCES.A . . . . . . . Abstracts in Journal of the Chemical Society (until1925) or in British Chemical Abstracts,* SectionA.Acta Phytochim. . . . Acta Phytochimicrt.Amer. J . Bot. . . . American Journal of Botany.Amer. J . Sci. . . . American Journal of Science.Amer. M in. . . . . American Mineralogist.Anal. Asoc. Quim. ArgentinaAnal. Fis. Quim. . . . Anales de la Sociedad Espanijla Fisica y Qufmica.Analyst .. . . . The Analyst.Angew. Chem. . . . Angewandte Chemie (formerly Zeitschrift fiir Ange-Anden . . . . Justus Liebig’s Annalen der Chemie.Ann. Acad. Brasil. Sci.Ann. Bot. . . . . Annals of Botany.Ann. Chim. . . . . Annales de Chimie.Ann. Chim. analyt. . . Annales de Chimje analytique et de Chimie rtppliqu6e.Ann. Chim. Appl. . . Annali di Chimica Applicata.Ann. Inst. Anal. Phys. Annales de 1’Institut d’Analyse physico-chimique,Ann. Physik . . . Annalen der Physik.Ann. Reports . . . Annual Reports of the Chemical Society.Ann. sci. Univ. Jassy . Annales scientifiques de l’Universit6 de Jassy.Ann. Soc. Sci. Bruxellesm6dicales et naturelles de Bruxelles.Arch. Eisenhfittenw. . . Archiv fur das Eisenhuttenwesen.Arch.Ist. biochim. ital. . Archivio dell’ Istituto biochimico italiano.Arch. Pharm. . . . Archiv der Pharmazie.Arch. Sci. biol., Russia . Archives des Sciences biologiques (U.S.S.R.).Arch. Sci. phys. nut. . . Archives des hiences physiques et naturelles.Arkiv Kemi, &in. Geol.Atti R. Accad. Lincei .Anales de la Asociaci6n Qufmica Argentina.wandte Chernie).. Annales da Academia Brasileira de Sciencias.Chim. Leningrad.. . ‘ Annales et Bulletin de la Soci6tb royale des Sciences. . Arkiv for Kemi, Mineralogi och Geologi.Atti (Rendiconti) della Reale Accademia Nazionaledei Lincei, classe di scienze fisiche, matematichee naturali. Roma.B. . . . . . . British Chemical Abstracts,* Section B.Ber. . . . . . Berichte der deutschen chemischen Gesellschaft.Ber.deut. bot. Bes. . . Berichte der deutschen botanischen Gesellschaft.Biochem. J . . . . . The Biochemical Journal.Biochem. 2. . . . . Biochemische Zeitschrift.Bol. min. SOC. nac. Min. .Bot. Caz. . . . . The Botanical Gazette.Brennstoff-Chem. . . Brennstoff -Chemie.Brit. Med. J . . . . The British Medical Journal.Bul. SOC. 8tiinte Cluj . . Buletinul SocietBtii de Stiinte din Cluj.Bull. Acad. Polonaise . . Bulletin Internationale de I’Aoadbmie Polonaise desBull. Acad. roy. Bdg. . . Academie royale de Be1gique.-Bulletin de la ClasseBull. A d . Sci. U.R.S.S. . Bulletin de l’bcadbrnie des Sciences de 1’Union desBull. Chem. Sm. Japan . Bulletin of the Chemical Society of Japan.Bull. Comm. gkol. Finlande Bulletin de la Commission geologique de Finlande.Bull. Inst.Min. Met. . . Bulletin of the Institution of Mining and Metallurgy.Bull. Inst. Phys. Chem. Res. Bulletin of the Institute of Physical and ChemicaTokyo Research, Tokyo.Bull. Sericult. Silk Ind. Bulletin of the Sericulture and Silk Industry, Japan.Japan * The year is not iiiserted in references to 1932.Boletin minero de la Sociedad nacional de Mineria(Chile).Sciences et des Lettres.des Scieuces.Rbpubliques Sovi6tiques Socialistesviii TABLE OF ABBREVIATIONS EMPLOYED IN THE REFERENCYES.Abbreviated Title.Bull. Soc. chim. , . .Bull. Soc. chim. Belg. . .Hull. Soc. Chim. biol. . .B?i 11. Soc. chim,. Y oiigosda, v.Bull. Soc. d’Encour. .Bull. Soc. f r a y . Min.Bull. Torrey Bot. ClubBur.Stand. J . Res. .Canadian J . Res. .Cellulosechem. . .Centr. Bakt. Par. . .Centr. Mi%. . . .Ce‘ram. et Verrerie .Chem. Erde . . .Chem. and Ind. . .Chem. Listy . . .Chem. News . . .Chem. Reviews . .Chem. Rund. Mitt eleu ropnChem. Weekblad . . .Chem. Zenlr. . . .Chem.-Ztg. . . . .Chim. et Ind. . . .Chinese J . Physiol. . .Cdl. Czech. Chem. Comm. .Compt. rend. . . .Compt. rend. Acad. Agrir.Compt. rend. Soc. Biol. .BalkanFranceContr. Boyce Thompson Inst.Corndl Univ. Agric. Exp.Econ. Geol. . . . .Eng. and Min. J.. . .Ermihr. Pjlanze . . .Fortschr. Chem. Ph?jaik .Gazzefta . . . . .Qeol. Hag. . .Bes. Abhundl. Kennt. Kohle..Qiorn. Chim. ind. appl. .Glastech. Ber. . . .Hdv. Chim. Acta . . .Ind.Chem. .. . .Ind. chim. . . . .Ind. Eng. Chem. . . .Ind. Eng. Chem. (Anal.) .Indian J . Physics . .J . . . . . . .J . Agric. Chem. SOC. JapanJ . Agric. Res. . . .Sta. Hem.FULL TITLE.Bulletin de la SociBtB chimique de France.Bulletin de la SocibtQ chimique de Belgique.Bulletin de la Sociktt? de Chimie biologique.Bulletin de la SociQtQ chimique du Royaume deBulletin de la SociBtB d’Encouragement pour 1’In-Bulletin de la SociBtQ frangaise de Mineralogie.Bulletin of the Torrey Botanical Club.Bureau of Standards Journal of Research.Canadian Journal of Research.Ccllulosechemie. Zeitschrift fiir Geriist-, Inkrusta-tions- und andere Begleitstoff e der Cellulose.See Zentr. Bakt. Par. (spelling changed in 1929).Centralblatt f i r Mineralogie, Geologie, und Palaon-tologie.CBramique et Verrerie.Chemie der Erde.Chemistry and Industry.Chemickb Listy pro V6du a Prbmysl. Organ de la“Cesk6 chemick& SpoleEnost pro VBdu aPrfimysl.’ ’Chemical News.Chemical Reviews.Chemische Rundschau fur Mitteleuropa und denChemisch Weekblad.Chemisches Zentralblatt.Chemiker-Zeitung.Chimie et Industrie.Chinese Journal of Physiology.Collection of Czechoslovak Chemical Communications.Comptes rendus hebdomadaires des SBances de1’AcadBmie des Sciences.Comptes rendus des Seances de l’Acad8mie d’Agri-culture de France.Comptes rendus hebdomadaires de SQances de laSocihtQ de Biology.Contributions from Boyce Thompson Institute.Cornell University Agricult,ural Experiment StationMemoirs.Economic Geology.Engineering and Mining Journal.Die Ernahrung der Pflanze.Fortschritte der Chemie, Physik und physikalischenGazzetta chimica italiana.The Geological Magazine.Gesammelte Abhandlungen zur Kenntnis der Kohle.Giornale di Chimica industriale et applicata.Glastechnische Berichte.Helveticti Chimica Acta.The Industrial Chemist and Chemical Manufacturer.L’Industrie chimica, mineraria e metallurgica.Industrial and Engineering Chemistry.Industrial and Engineering Chemistry : AnalyticaIndian Journal of Physics.Journal of the Chemical Society.Journal of the Agricultural Chemical Society of!ownal of Agricultural Research.Yougoslavie.dustrie nationale.Balkan.Chemie.Edition.JapanTABLE OF ABBREVIATIONS EMPLOYED IN THE BEEERENCES.ixAbbrezdated Title.J . Agric. Sci. . . .J . Amer. Ceramic Soe. .J . Amer. Chem. Soc. . .J . Amer. Phamn. Assoc. .J . Amer. SOC. Agron. . .J . Appl. Chem. Russia .J . Biol. Chem. . .J . Chem. Met. Min. S.J . Chim. physique . .J . Counc. Sci. Ind. Res.J . Dept. Agric. Kyushu .J . Exp. Med. . . .J . Fac. Agric. Hokkaido .J . Franklin Inst. .J . Gen. Chem. (U.S.S.R.) 1AfricaAustraliaJ . Ind. Eng. Chem. . .J . Indian Chem. Soc. . .J.Iwt.dletals . . .J . Inst. Petrol. Tech. . .J. Iron Steel Inst. . .J . dlarine Biol. Assoc. .J . Path. Bat. . . .J . Pharm. 8oc. Japan .J . Physical Chem. . .J . Physid. . . . .J . Pomology . . . .J . pr. Chem. . . . .J . Proc. Roy. Soc. N.S.W. .J . Roy.Soc. W. Australia .J . Russ. Phys. Chem. SOC. .J . Soc. Chem. Ind. . .J . Soc. Chem. Ind. Japan .J . SOC. G h s Tech. . .J . Tokyo Chem. doc. . .J . Wash. A d . Sci. . .Jahrb. Min. . . . .Jahrb. Min., Be&-Bd. .Jahrb. t&s. Bot. . . .Jap. J. Qed. Qeog. . .Japanese J . Physics . .Jap. Med. Lit. . . .I<. Bvenska VetenakapsKeram. i Steklo . . .Lancet . . . . .Latvij. Univ. Raksti . .Akad. H a d .FULL TITLE.The Journal of Agricultural Science.Journal of the American Ceramic Society.Journal of the American Chemical Society.Journal of the American Pharmaceutiwl Association.Journal of the American Society of Agronomy.Zhurnal prikladnoi Chimii.Journal of Biological Chemistry.Journal of the Chemical, Metallurgical and MiningSociety of South Africa.Journal de Chimie physique.Journal of the Council for Scientifk and IndustrialResearch (Australia).Journal of the Department of Agriculture, KyushuImperial University.Journal of Experimental Medicine.Journal of the Faculty of Agriculture, HokkaidoImperial University.Journal of the Franklin Institute.Journal of General Chemistry (U.S.S.R.) (formerlychemical part of the Journal of the Physical andChemical Society of Russia).Journal of Industrial and Engineering Chemistry(now Industrial and Engineering Chemistry).Quarterly Journal of the Indian Chemioal Society.Journal of the Institute of Metals.Journal of the Institute of Petroleum Technologists.Journal of the lron and Steel Institute.Journal of the Marine Biological Assocktion of theUnited Kingdom.Journal of Pathology and Bacteriology.Journal of the Pharmaceutical Society of Japan(Yakugakuzasshi).The Journal of Physical Chemistry.The Journal of Physiology.The Journal of Pomology and Horticultural Science.Journal fiir praktische Chemie.Journal and Proceedings of the Royal Society of NewJournal of the Royal Society of West AustraliazJournal of the Physical and Chemical Society ofRussia (now Journal of General Chemistry,U.S.S.R.).Journal of the Society of Chemical Industry.Journal of the Society of Chemical Industry, Japan(K6gy6 Kwagaku Zasshi).Journal of the Society of Glass Technology.Journal of the Tokyo Chemical Society (now Journalof the Chemical Society of Japan).Journal of the Washington Academy of Sciences.Neues Jahrbuch fiir Mineralogie, Geologie undPalaontologie.Neues Jahrbuch fiir Mineralogie, Geologie undPaljiontologie, Beilage-Band.Jahrbucher fiir wissenschaftliche Botanik.Japanese Journal of Geology and Geography.Japanese Journal of Physics.Japanese Medical Literature (discontinued in 1921).Kongliga Svenska Vetenskaps Akademiens Hand-lingar.Keramika i Steklo (Ceramics and Glass).The Lancet.Latvijas UniversitMes Raksti.South Wales.A X TABLE OF ABBREVIATIONS EMPLOYED IN TnE REBEBENCES.Abbreviated Title.Mem.Coll. Sci. Kyoto .Mem. R. Accad. d’ltalia .Dlem. h’t~ojun Coll. Lng. .Met. ital. . . . .JlPtall I ( . Erz . . .Illilcrochem. . . . .Min. Jlag. . . . .Missouri Agric.Exp. Sta.Monatsh. . . . . Res. Bull.Mysore Univ. J . . . .N . 2. J . Sci. Tech. . .N w h . Ces. Wiss. Gdttingen.Naturwiss. . . . .Natuurwetensch. Tijds. .Nebraska Agric. Expt. Sta.New Jersey Agric. Expt.Ohio Agric. Exp. Sta. Bull.PJlanzenbau . . . .Pharrn. J . . . .~hxzmn. Wee&& . .Phurrn. Zentr. . . .Pharm. Ztg. . . . .Phil. Mag. . . . .Phil. Trans. . . . .Physical Rev. . . .Physikal. 2. . . . .Planta . . . . .Bull.Sta. Bull.Plan$ Physiol. . . .Praktika . . . .Proc. Amer. SOC. Hort. Sci.Proc. Austral. Inst. Bin.Proc. Camb. Phil. Soc. .Proc. I m p . Acad. Tokyo .Proc. I I I Int. Conf. Bit.Proc. K . Akad. Wetensch.Proc. Nut. Acad. Sci. . .Proc. Physical SOC. . .Proc. Roy. SOC. .. .Proc. Roy. Soc. Edin. . .Proc. SOC. Exp. Biol. Ned.Protoplasm . . . .Proc. World Eag. Congr.Quart. J . Qeol. SOC. . .Quart. J . Pharm.. . .Met.CodAmsterdamTokyoFULL TITLE.Memoirs of the College of Science, Kyoto ImperialUniversity.Memorie della reale Accademia d’Ttalia..Memoirs of the Ryojun College of Engineering.Metallurgia Italiana.filetall und Erz.Mikrochemie.Mineralogical Magazine and Journal of the Minera-Missouri Anricultural ExDeriment Station Researchlogical Society.Bullet&.Monatshefte fur Chemie und verwandte Theileanderer Wissenschaften.The Half-yearly ,Journal of the Mysore University.New Zealand Journal of Science and Technology.Nachrichten von der Gesellschaft der WissenschaftenDie Naturwissenschaften.Natuurwetenschappelijk Tijdschrift.Nebraska Agricultural Experiment Station Bulletin.New Jersey Agricultural Experiment StationOhio Agricultural Experiment Station Bulletins.Wissenschaftliches Archiv fur Landwirtschaft.Ab-teilung A. Pflanzenbau.Pharmaceutical Journal.Pharmaceutisch Weekblad.Pharmazeutische Zentralhalle.Pharmazeutische Zeitung.Philosophical Magazine (The London, Edinburgh andDublin).Philosophical Transactions of the Royal Society ofLondon.Physical Review.Physikalische Zeitschrift.Zeitschrift fiir wissenschaf tliche Biologie. AbteilungE. Planta. Archivfiir wissenschaftliche Uotanik.Plant Physiology.Praktika (Akademia Athenon).Proceedings of the American Society of HorticulturalScience.Proceedings of the Australasian Institute of Miningand Metallurgy.Proceedings of the Cambridge Philosophical Society.Proceedings of the Imperial Academy of Japan.Proceedings of the International Conference onKoninklij ke Akademie van Wetenschappen te Am-Proceedings of the National Academy of Sciences.Proceedings of the Physical Society of London.Proceedings of the Royal Society.Proceedings of the Royal Society of Edinburgh.Proceedings of tho Society for Experimental BiologyInternationale Zeitschrift fiir physikalische ChemieProceedings of the World Engineering Congress,The Quarterly Journal of the Geological Society.Quarterly Journal of Pharmacy and Pharmacology.zu Gottingen.Bulletin.Bituminous Coal : 3rd Conference.sterdam.and Medicine.des Protoplasten.Tokyo, JapanTABLE OF ABBREVIATIONS EMPLOYED IN THE REFERENCES.xiI Abbreviated Title.Rec. Geol. Surv. India .Rec. trav.chim. . . .Rensselaer Poly. Inst. . .Rev. Chim. pura appl. .Rev. Mod. Physics . .Rev. Sci. Instr. . . .Rocz. Chem. . . . .Schweiz. Apoth.-Zlg. . .Sci. Papers Inst. Phys.Sci. Rep. TGhoku Imp. Univ.Sitzungsber. +reuss. AkadSoil Sci. . . . .Sucre. belge . . . .Suomen Kern. . . .Svensk Kem. Tidskr. . .Tech. Rep. TGhoku . .Tidsskr. Kjemi Berg. . .Tonind.-Ztg. . . . ,Trans. Faraday Soc. . .Trans. Ill. Acad. #ci. . .Chem. Res. TolcyoWiss. BerlinTrans. Roy. SOC. Canada .Trans. Roy. SOC. S. AfricaTrans. State Inst. Test.Building Mat. . . .Tsch. min. petr. iUitt. .U.S.Bureau Mines Rep.U.S. Dept. of Agric. . .U.S. Geol. Survey Bull. .Univ. Illinois Bull. . .Univ. Toronto Stud. Ceol.Veroff. Kaiser Wilhelm-Imt.IV. Austral. Geol. Szirv.Wiss. Arch. Landw. . .Z.anal.Chem. . . .2. angew. Chem. . . .2. aitorg. Chem. . . .Z. deut. geol. Ges. . .2. Elektrochem. . . .2. Krist. . . . .2.iffent.l. Chem . . .2. PJEanz. Diing. . . .2. Physik . . . .Z. physikal. Chem. . .Z . physiol. Chem. . .2. Unlers. Lebensm. . .8. Vitaminforsch. . .Zentr. Bakt. Par. . . .InvestigationSilikatforsch.Bull.FULL TITLE.Records of the Geological Survey of India.Recueil des travaux chimiques des Pays-Bas et deRensselaer Polytechnic Institute, Engineering andRevista de Chimica pura e applicata.Reviews of Modern Physics.Review of Scientific Instruments.Roczniki Chemji organ Polskiego TowarzystwaSchweizerische Apotheker-Zeitung.Scientific Papers of the Institute of Physical andScientific Reports, T6hoku Imperial University.Sitzungsberichte der preussischen Akademie derSoil Science.La Sucrerie belge.Suomen Kemistilehte (Acta Chemica Fennica).Svensk Kemisk Tidskrift,.The Technology Reports of the T6hoku ImperialUniversity.Tidsskrift for Kjemi og Bergvaesen.Tonindustrie-Zeitung.Transactions of the Paraday Society.Transactions of the Illinois State Academy orTransactions of the Royal Society of Canada.Transactions of the Royal Society of South Africa.Transactions of the State Institute for Testing Build-Tschermaks mineralogische und petrographischeUnited States Bureau of Mines Reports of Investi-United States Department of Agriculture.United States Geological Survey Bulletins.University of Illinois Bulletins.University of Toronto Studies : Geological Series.Veroffentlichungen aus dem Kaiser Wilhelm-Insti-tut fiir Silikatforschung in Berlin-Dahlem.Western Australia Geological Survey Bulletins.Wissenschaftliches Archiv fiir Landwirtschaft.Zeitschrift fur analytische Chemie.Zeitschrift fiir ongewandte Chemie.Zeitschrift fiir anorganische und allgemeine Chemie.Zeitschrift der deutschen geologischen Gesellschaft.Zeitschrift fiir Elektrochemie (und angewandtephysikalische Chemie).Zeitschrift fiir Kristallographie.Zeitschrift fiir offentliche Chemie (suspended in1922).Zeitschrift fiir Pflanzenerniihrung und Diingung.Zeitschrift fiir Physik.Zeitschrift fiir physikalische Chemie, StochiometrieHoppe-Seyler’s Zeitschrift ftir physiologische Chemie.Zeitschrift fur Untersuohung der Lebensmittel.Zeitschrift fiir Vitaminforschung.Zentralblatt fiir Bakteriologie, Parasitenkunde undla Belgique.Science Series.Chemicznego .Chemical Research, Tokyo.Wissenschaften zu Berlin.Science.ing Materials and Glass.Mitteilungen.gations.und Verwandtschaftslehre.Infektionskrankheiten

ISSN:0365-6217    

DOI:10.1039/AR9322900001

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

ANNUAL REPORTSON TEEPROGRESS OF CHEMISTRY.GENERAL AND PHYSICAL CHEMISTRY.1. GENERAL.IN spite of the aloofness of the atomic nucleus from ordinarychemical affairs, the problem of its structure is in some ways themost fundamental one so far presented to chemistry. The greatdifficulty has been the absence of even the &st beginnings of a theoryabout the forces holding the various components of the nucleustogether. The radiations from radioactive substances, the displace-ment law, the identity of nuclear charge and atomic number, theexistence of isotopes, and the production of protons by artificialdisintegration, all go to show that protons, a-particles, and electronsare in some way involved in the make-up of the nucleus. Thatthere is profound interaction of some kind between these componentsis revealed perhaps most strikingly by the mass defect.Thatthere are sub-structures within the main structure is implied in allthe theories in which the a-particles in the nucleus retain theiridentity. The existence of energy levels is strongly indicated byanalysis of the y-ray emissions. The size relationships of thisextraordinary system are inconceivable in terms of macroscopicanalogies, and most physical pictures which have been suggestedinevitably contain inconsistencies and contradictions. Never-theless, that some satisfactory form of nuclear statics and dynamicswill presently be evolved seems almost certain. This anticipationis based upon the fact that in some respects nuclear processes, inspite of the difficulty of visualising them, are so very simple in theirexternal results.One example may be quoted. The most strikingexperimental advance during the past year has been the artificialdisintegration of elements by protons accelerated by extremelyhigh voltages.2 The lithium nucleus, when hit by a proton of1 Cf. Discussion on Structure of Atomic Nuclei, Proc. Roy. SOC., 1932, [A],136, 735; A., 791.J. D. Cockcroft and E. T. S. Walton, ibid., 137, 229; A., 89314 GENERAL AND PHYSICAL CHEMISTRY.several hundred thousand volts energy, appears t o capture theproton and break up into two a-particles: Li7 + H1 = 2He4.This opens up the prospect of a whole system of nuclear chemistry,by which theoretical predictions of stability relationships can betested.The Gamow theoryY3 treating the nucleus as a system containinga-particles confined within a high positive potential barrier throughwhich they escape at a slow steady rate, enables a fairly accurateaccount to be given of the relation between the energy of a-particlesand the half-life of the atoms emitting them.But if there areelectrons as such in the nucleus, they would not be confined by thissame kind of barrier : thus the picture is seen to be an incompleteone. F. A. Lindemannl has expressed the view that attempts torepresent the nucleus in spatio-temporal terms cannot possiblysucceed, or be more than metaphors.W. Heisenberg has recently started to construct a theory of thenucleus, which, while not spatio-temporal in the classical sense, ismuch more fundamental and direct than theories expressed in termsof potential barriers or other semi-empirical conceptions.The great simplifying factor which has made Heisenberg’s newtheory possible is the discovery of the neutron.5 This entity,which turns up when beryllium is bombarded with a-particlesfrom polonium, appears to have unit mass and no charge.It couldbe conceived for some purposes as an electron and a proton fusedtogether. The evidence that the beryllium radiation really doesconsist of neutrons is too detailed to be snmmarised briefly here, andthe result will be accepted for the purpose of discussing the theoryof nuclear forces.If there are neutrons, it is no longer necessary to postulate theexistence of free electrons in nuclei.The atomic weight has tobe about twice the atomic number. Instead of interpreting thisby saying that there are about twice as many protons as electronswe can now say that there are about equal numbers of protons andneutrons. According to Heisenberg, the best way is to regard theneutron, not as something containing a proton and an electron,but as an independent fundamental component of the nucleus. Itis to be thought of, however, as capable of generating an electronand a proton in some way. The theory considers the forces betweenthe various components of the nucleus. In the first place, there isthe ordinary Coulomb repulsion between the protons, and, secondly,Cf. Ann. Reports, 1930, 27, 26.2. Physik, 1932, 77, 1; 78, 156; A., 594, 1074.J. Chadwick, Proc.Roy. SOC., 1932, [ A ] , 136, 692; A . , 790; (Rlme.) I.Curie and F. Joliot, Nature, 1932, 130, 57 ; A., 895RINSHELWOOD : QENERAL. 15there are attractive forces betwesn neutrons and between neutronsand protons. The attractive forces are treated quantum-mechanically. Those between neutrons and protons are of the“ exchange ” type.6 (It may be well briefly to recall what this means.If a neutron and a proton are in proximity, and the negative chargechanged places, passing into what was originally the proton, thefinal state would be indistinguishable from the initial. In wavemechanics the probability of a given state is determined by theamplitude of a certain function which varies harmonically with time.If two states are indistinguishable, the corresponding amplitudeswax and wane alternately at the expense of one another.Thiswaxing and waning is analogous to the interchange of amplitudebetween two similar pendulums in resonance, and does indeed comeabout for the same mathematical reason, since it depends upon theidentical frequencies associated with states of equal energies. Re-sonance is always associated with the production of a new frequencylower than the undisturbed frequency. Throughout quantummechanics the connection between frequency and energy is offundamental importance. Thus the same equations which predictthe “ interchange ” of, say, the negative charge between the neutronand the proton, provide also for the existence of a state of lowerenergy than that corresponding to the energies of the completelyseparated particles.In other words, an attractive force exists.)The magnitude of the force is, in principle, derivable from “ exchangeintegrals.” Heisenberg constructs the Hamilton function for thenucleus, and from considerations of a rather general character arrivesat a number of interesting results. Considering the influence ofthe exchange forces only, he concludes that the minimum energy,i.e., maximum stability, would be reached when the numbers ofneutrons and protons present are about equal. The influence ofthe other forces is to displace the stable number somewhat in favourof neutrons.From the known stability of helium nuclei, it must be supposedthat a system of two protons and two neutrons forms somethinganalogous to a “ closed ” or “ completed shell.” The picture ofP-ray disintegration is as follows : a nucleus consisting only ofneutrons would change neutrons into protons by sending out P-raysuntil the energy which is gained by adding a proton is exactly equalt o that which is used up in removing a neutron.For smaller numbersof neutrons the nucleus is stable towards (3-disintegration. If thenumber of neutrons gets to‘o small, the Coulomb repulsion of thepositive charges leads to u-ray decay : a-particles, and not protons,are emitted, since (3-disintegration ceases at a point where the removal* Cf. Ann. Reports, 1930, 27, 1416 GENERaL AND PHYSICAL CHEMISTRY.of a proton still requires energy, though an a-particle, being lesstightly bound than a proton, can escape.The ratio, n,/n2, of thenumber of neutrons t o protons has, for a given value of n2, an upperand a lower limit, corresponding to (3- and a-disintegration respec-tively. Owing to the great stability of the helium nucleus, thereare often two successive P-ray changes if initially the atomic numberis even, but if one starts from an odd atomic number, there mayonly be one. p-Ray changes may be followed by a-disintegrationuntil nl/n2 once again rises above a limiting value.Heisenberg investigates the stability of nuclei with even andodd numbers of neutrons, and also dea,ls with the question of thescattering of y-rays by atomic nuclei.In the last Report, reference was made to the view that theemission of y-rays is associated with the transition of a-particlesbetween energy levels in the nucleus.Further work lends additionalsupport to this idea,. It has been shown, for example, that certainy-rays, known to be associated in some way with thorium4 orthorium-C’, are given out as an immediate consequence of thedisintegration of thorium-C.7 Again, actinium emanation emitstwo groups of a-particles : in the transformation of the emanationinto actinium-A, y-rays are emitted, the quantum energy of whichis found to be of the right order of magnitude to correspond to thedifference in energy of the two a-particle groups.*Perhaps one of the most striking results of quantum mechanicsis the prediction of enhanced probability of transition betweentwo states of a complex system when the total energy of one stateis very nearly equal t o that of the other.(The phenomenon iscalled resonance, since it depends mathematically upon equalityof frequency in the wave functions describing the different states.)From the general point of view, therefore, great interest attachest o the interpretation given by 5. Chadwick and J. E. R. Constableto their experiments on the artificial disintegration of fluorine andaluminium nuclei by a-particles. When these elements are born-barded with a-particles from polonium, the protons liberated canapparently be resolved into definite groups. (These groups,moreover, occur in pairs, suggesting that there are two ways inwhich an a-particle can be captured, the first giving an excitednucleus and a short-range proton, the second giving a stable nucleusand a long-range proton.) The four groups of two found withaluminium are supposed t o indicate the existence in the nucleusof four “resonance levels.” Penetration of the nucleus by the’ C.D. Ellis, Proc. Roy. SOC., 1932, [ A ] , 136, 396.* (Lord) Rutherford and B. V. Bowden, ibid., p. 407.Ibid., 135, 48 ; A., 318HMSHELWOOD : GENERAL. 17a-particle with insufficient energy to surmount the “ potentialbarrier ” can occur if the particle has exactly the energy correspond-ing to a resonance level. A detailed consideration of the techniqueof the kind of experiment upon which these conclusions are basedis obviously far outside the scope of this Report.It ought, however,to be mentioned that in certain cases difficulties of interpretationseem to arise.1° This means that, while the theoretical interest of theproblems raised is very great, even more investigation is necessarybefore the fullest confidence can be felt in any general conclusion.Another line of attack on the nucleus which looks like beingsuccessful is the investigation of nuclear magnetic moments andwhat are called “ g(1) factors,” Le., ratio of magnetic to mechanicalmoment, based upon the measurement of the hyperfine structureof spectral lines.11 This is just mentioned here, but it is not pro-posed to discuss the results in detail.It will be evident, even from the few examples quoted above,that nuclear chemistry is in a state of rapid development.We will now turn to the consideration of certain matters connectedwith the more accessible parts of the atom, starting with somerecent work on the nature of the chemical bond.The customary distinction between an ionic bond and a covalentor electron-pair bond appears to be quite sharp and definite as longas attention is fixed upon extreme cases. But the question whetherthere is a continuous transition from one to t’he other has alwaysbeen a subject for discussion.From a “ semi-quantitative ”quantum-mechanical treatment of the problem, L. Pauling 12arrives a t the conclusion that there will be a continuous transitionfrom one type of bond t o the other only when the lowest ionic stateof the molecule and the lowest covalent state have the same numberof unpaired electrons.Making approximate estimates of differentkinds of binding energies, he concludes that alkali halides are ionic,that the molecules HC1, HRr, and HI have electron-pair bonds,while HF is “ largely ionic.”When two electronic structures of about the same energy arepossible for a molecule, the quantum-mechanical resonancephenomenon comes into play with rather strange results. Thewave function for the normal state of the system is best representednot by either of the functions describing the two separate statesbut by a linear combination of the two functions. The meaningof this is supposed to be that the molecule oscillates rapidly betweenlo Cf. discussion a t the end of the paper by E.Steudel, 2. Physik, 1932, 77,l1 Cf. J. C. McLennan, Proc. Roy. SOC., 1932, [ A ] , 136, 735; A., 791.la J . Amer. Chem. SOL, 1932, 54, 988; A., 561.139 ; A., 98018 GENERAL AND PHYSIUAL UHEMISTRY.the two possible structures. Carbon monoxide, according to Pauling,provides an example of this kind of behaviour and fluctuates betweenthe structures given by :C::b’: and :C:::O:, the latter being thepredominant f orm.13It is a striking fact that the energies of individual bonds asderived from heats of formation and heats of combustion areapproximately ~0nstant.l~ The quantum-mechanical translationof this fact may be expressed by saying that the properties of abond are often “ determined by one single-electron orbital wavefunction for each atom and are not strongly affected by other atomsin the molecule.” To what extent this principle can be establishedrigidly by a priori reasoning the reviewer is not competent to state.But even if largely empirical, the rule is a useful one.Pauling l5concludes from an examination of therrnochemical evidence thatthe energies of normal covalent bonds are additive. This meansthat relations of the following kind hold : A:B =&(A:A + B:B),where A:B represents the energy of a bond between A and B.This applies only to normal covalent bonds, by which are meantbonds in which the electrons are equally shared by the two atoms.If A and B are not equally electronegative the bond assumes acertain ionic character. According to Pauling, the energy of anactual bond must be a t least as great as that for a normal covalentbond.Moreover, the difference between the actual energy and thatcalculated by assuming additive relationships will be greater themore pronounced the ionic character of the bond. For example,H:H is 4.44 v.e., F:P is 2-80; both of these are normal bonds, sincethe two atoms are in each case identical. From the additive principle,the normal covalent bond between H and P should have an energy+(4.44 + 2-80) = 3.62. The actual value for H:F is 6-39, which isin fact much greater than the “ normal ” value. The difference,A, decreases steadily as we pass to the heavier halogens : with H:Ithe value calculated from additivity is 2.99, while the real value is3.07, giving A = 0.08.Pauling finds A to be positive in 20 out of21 examples. It then appears that there are regularities amongthe A values themselves : the values of All2 are observed to beapproximately additive. This relation is illustrated by the follow-ing numbers, the unit being the electron-volt.C-H actual ..................... 4.34 C-F actual ..................... 5.40C-H from additive relation ... 4.02 C-F from additive relation ... 3.20~ 1 ’ 2 ................................. 0.57 A’/2 ................................. 1.48A .................................... 0.32 A .................................... 2-20~~~13 See (12); also Proc. Nat. Acad. Sci., 1932,18, 293; A . , 562.1 4 Cf. Ann. Reports, 1931, 28, 385.15 J . A m r . Chem. SOC., 1932, 54, 3570 ; L.Paiiling and D. M. Yost, Proc.Nut. Acud. Sci., 1932, 18, 414; A., 901HZNSHELWOOD : CJENER&. 19Thus Similarly from N-H and N-F it isfound that A& + A& = 2-06.This suggests that the actual value of any AAB can be expressedin the form (xA - xB)2, where x, and zB are co-ordinates of theelements in some scale. Thus if the following numbers are assignedto various elements :+ A& = 2.05.H P I S C B r C l N O F0.0 0.10 0.40 0.43 0.55 0.75 0.94 0.95 1.40 2.00the value of any Am can be calculated. For example,will be (0.55 - 0)2 = 0.552,AeF will be (2.00 - 0 ~ 5 5 ) ~ = 1-45,’ and so on.Since the magnitude of AAB depends upon the ionic characterwhich the bond acquires by the unequal sharing of electrons betweenthe two atoms, the greater its value the further apart in a scale ofelectronegativity must the two atoms be.Thus the above seriesgives a quantitative measure of the electronegative character ofthe different atoms. The arrangement of the atoms in this definiteorder is extremely useful for purposes of discussing the propertiesand reactions of chemical substances. Quite often the relativedegrees of electronegativeness of various atoms have had to beassumed ad hoc for the purposes of this or that theory, but the presentseries provides a standard I based upon independent measurements.Incidentally, the series is useful for computing bond energies whichare not easily accessible to measurement.The forces which atoms exert upon one another are not of asimple nature.The Heitler-London type of valency force, whichgives rise to a bond consisting of two electrons with antiparallelspin moments, is reinforced or opposed by various other inter-actions including “ polarisation forces.” If two atoms with parallelspin moments approach, the effect predicted by the Heitler-Londontreatment is repulsion. This is opposed by the attractive force dueto mutual polarisation. For two hydrogen atoms the influence ofthis factor is considered to be unimportant, but with the alkalimetals it seems that the energy relations are quite different and that“ polarisation molecules ” may be formed. According to H.Kuhn,lG there occur in alkali-metal vapours, near the principalseries lines, absorption bands due to such molecules.The bandsare said to be quite Werent from the well-known bands of the Na,type, and occupy a, very narrow spectral region near the atomiclines, on account of the smallness of the energy of dissociation.Kuhn suggests that the following sequence should be traversed byalkali absorption spectra as the pressure is increased : atomic,2. Physik, 1932, 76, 78220 GENERAL AND PHYSICAL CHEMISTRY.true molecules (singlet state) , polarisation molecules, and finally,continuous absorption from atoms a t the moment of collision-What is interesting from our present pointof view is not the validity of any given interpretation of particularspectroscopic observations, but the elaborate possibilities of atomicinteraction which appear in general to be possible.We now advance one stage further in complexity, namely, tocarbon compounds.The success with which organic chemistry has solved its problemsby the aid of its own conceptions about the nature of chemicalbonds has, during the last few years, stimulated theoretical physiciststo attempt the translation of these conceptions into the language of.quantum mechanics.It is as well to realise a t the outset that eventhe simplest problems of organic chemistry are much too complicatedfor anything like a complete and fundamental treatment not basedupon drastic simplification and not introducing a considerablemeasure of assumption. The theoretical investigation, therefore,can hardly be expected to predict new phenomena in organicchemistry.Nevertheless, it is satisfactory that the known phenomenacan be described in terms acceptable to physicists, and that the rulescan be formulated in ways which at least are not inconsistent withquantum-mechanical principles. In previous Reports referencehas been made to theoretical interpretations of the rigidity of doublebonds, the stability of ring systems, and substitution into thebenzene n~c1eus.l~ Such matters have been further dealt withby F. Hund,18 and by E. Huckel,l9 and H. Eyring 2O has discussed theproblem of steric hindrance.Huckel refers the characteristic behaviour of benzene to theexistence of a kind of closed group of six [p]h electrons (the properfunction of which has a node in the plane of the ring). Me treatstheir interaction by a method similar to that used by Bloch for work-ing out the interaction of electrons in metals, and extends the dis-cussion to include naphthalene, anthracene, phenanthrene, di-phenyl, and conjugated chain systems.All the rings are assumedto be plane, the plane arrangements being “ stabilised by the chargedistribution of the [p]h electrons with the node of the proper functionsin the plane of the atoms.” He makes calculations about thesymmetry of the various proper functions, and arrives at variousconclusions. Condensed ring systems all possess completed electrongroups like benzene, and the binding energy per electron is not veryquasi-molecules.” < Cl 7 Huckel’s views on this matter have been criticised by A. Lapworth andl8 2.Physik, 1932, 73, 565; A . , 215.2o J . Amer. Chem. Xoc., 1932, 54, 3191; A., 996.R. Robinson, Nature, 1932, 129, 278.Ibid., 76, 628(6 TRUE ” DEGREE OF DISSOCIATION OF STRONG ELECTROLYTES. 21different from that of the electrons in benzene. Huckel remarksthat the addition of alkali metals occurs with different ease withthe different compounds, and that the “ same order exists for theenergy of the lowest unoccupied states.” The position of the lowestunoccupied state (i.e., its energy level) is a measure of the“ Abgeschlossenheit ” (i.e., completeness, closed nature, orstability) of the electron group in respect to the taking up of electrons.Eyring’s discussion of steric hindrance is based upon differentprinciples. He uses potential-energy curves first in consideringthe approach and “ collision ” of two molecules, and then in treatingthe rotation of two methyl groups about an axis joining the twocarbon atoms.The transition between covalent and electrovalent bonds, andthe complexity of atomic interactions in general, are subjects whichcome very much into prominence in the theory of electrolytes.The Debye-Huckel theory having shown that the most importantproperties of dilute solutions of strong electrolytes can be accountedfor by assuming complete ionisation, the question arises whetherexisting deviations from the theory are partly due to the existencein solution of real molecules even of such substances as sodiumchloride.This matter, and also the question of heat of dilution,which depends upon interionic forces and the forces between ionsand dipole solvent molecules, is discussed in the following sections.C.N. H.2. THE “ TRUE ” DEGREE OF DISSOCIATION OF STRONUELECTROLYTES.This problem presents itself in several rather complicated aspects.In the first place it involves the prior question as to whether any-thing equivalent to a molecule really exists in the solution of a strongelectrolyte; if this question be decided in the negative, it is stilllegitimate to enquire whether it is not desirable on the grounds ofexpediency alone to treat as molecules complexes of oppositelycharged ions associated with a certain degree of permanence, and thussomewhat arbitrarily to divide the solution into ions and molecules.The second major problem, which arises if either of the first twoquestions is answered in the affirmative, is that of determining the“ true ” degree of dissociation.The answer to the first question-whether molecules exist insolutions of strong electrolytes or not-may be sought in two distinctways.On the one hand, we may examine the electrolyte for pro-perties which we have reason to believe are characteristic of undis-sociated moleoules ; this is the more distinctively experimentalapproach. On the other hand, we may endeavour to refine th22 GENERAL AND PHYSIUAL CHEMISTRY. WOLBENDEN :original calculations of Debye and Hiickel so as to extend theirapplicability to less dilute solutions ; if the mathematical difficultiesinvolved in this can be overcome, we can then compare thetheoretical predictions with the experimental data and thus testthe adequacy of the purely electrostatic picture of a moderatelyconcentrated solution.The only properties characteristic of undissociated molecules,which are available in this connexion, are their volatility or solubilityin a non-polar solvent and their optical properties.The vapourpressure of hydrogen halides above their aqueous solutions isunmistakable qualitative evidence of the existence of a small con-centration of molecules in solution, but no quantitative estimateof their amount can be made without introducing a hypotheticalpartition coefficient for the molecules. By using arguments byanalogy with alkyl halides or with hydrogen cyanide, respectively,the concentration of molecules in 0-O1M-hydrogen chloride solutionwas found to be 5.9 x 10-l2 by L.Ebert 21 and 3 ‘x 10-lO by K.Fajans.22 Treating the vapour pressure data in a different may,W. F. K. Wynne-JonesZ3 has estimated the concentration of un-dissociated hydrogen chloride in M-solution to be 4 x 10-8. Thesevalues are probably of’ the right order and indicate the extremelylow concentration of molecules present a t a concentration where theconductivity ratio is about 0.97. Partition methods are inapplic-able to salts, and here we have to rely on the optical propertiespeculiar to undissociated molecules ; these are respectively the re-fractive index, the absorption spectra, and the Raman spectra ofelectrolytic solutions.Independently of‘ his rather speculativetheory of deformable ions, I<. Pajans 24 has shown that the changeof the refraction of salt solutions with increasing concentration runsparallel with the changes in refraction with concentration of the corre-sponding acids where the refraction is tending towards the refractionof the pure covalent acid; this may be regarded as qualitative evi-dence of incomplete dissociation. Faj am’s other more quantitativearguments to the same end are based on his hypothesis of deform-able ions and are more equivocal. E. Schreiner 26 has endeavouredto make a quantitative estimate of the degree of dissociation ofhydrogen chloride and bromide in 4N-solution from refractiondata ; his values, 94.6% and 96-676 respectively, correspond tomuch less complete dissociation than the partition data suggest.z1 Naturwiss., 1926, 13, 393.23 Trans.Il’araday SOC., 1927, 23, 357; A., 1927, 1023.23 J . , 1930, 1064; A., 1930, 859.24 See E. Lange, Physikal. Z., 1928, 29, 767.35 Naturwiss., 1925, 13, 245(( TRUE ” DEGREE OF DISSOCIATION OB STRONG ELECTROLYTES. 23The absorption curves of nitric acid and of various salts over arange of concentrations show a common intersection point, accord-ing to H. von Halban.26 Such a phenomenon would occur if thesolute were changing progressively from one form with its character-istic absorption curve into another. Halban regards the two formsas molecules and ions respectively; he finds further evidence forincomplete dissociation in the deviations from Beer’s law shownby numerous salts in concentrated solution.Of the experimental methods available for the detection of un-dissociated molecules in solution, there can be little doubt that thestudy of the Raman spectra of electrolytes is by far the most elegantand the most satisfactory from a theoretical point of view.Theinteratomic linkage formed when two ions unite to form a moleculemust lead to the development of one or more distinctive Ramanlines. If, therefore, the Raman spectrum of a solution of anelectrolyte shows lines other than those known t o be characteristicof the solvent and of the constituent ions of the electrolyte, it maybe safely inferred that midissociated molecules are present ; 27since ions whose electron shells are of the inert-gas type produceno Raman lines themselves, the criterion is peculiarly clear-cut forsalts like the alkali halides.The principal defect of the method isthat, a t the present state of development of technique, the line-producing molecule must be present in substantial concentrationif it is to be detected; Raman spectra cannot therefore be expectedto show the presence of undissociated molecules whose concentrationis much less than, say, 0-1N. The experimental results of L. A.Woodward 2s and others reveal PO molecules as present in aqueoussolutions of potassium chloride, hydrogen chloride, potassiumcyanide, hydrogen fluoride, iodic acid, and sodium hydroxideamongst others, whereas solutions of nitric acid, mercuric chloride,and mercuric cyanide show molecules; the Raman spectra ofsolutions of sulphuric acid show very clearly the progressive dis-appearance of the molecules and intermediate ions as the concen-tration diminishes.Perhaps the only surprising feature of the resultsis the absence of any evidence for molecules in solutions of hydrogenfluoride.a 6 2. Ebktrochem., 1928, 34, 489.Except for the theoretical possibility that the mutual approach of theions in concentrated solution may remove the “ Verbot ” on an existingfrequency inside om of the ions by disturbing the symmetry property whichpreviously forbade its appearance; see G. Placzek, 2. Physik, 1931, 70, 84;A., 1931, 893, and Leipzigsr Vortrage (“ Molekiilstruktur ”), 1931, p.71.(Private communication from Nr. L. A. Woodward.)This paper contains a usefulbibliography.28 Physikal. Z., 1931,32,777 ; A., 1931,136724 GENERAL AND PHYSICAL CHEMISTRY. WOLFENDEN :Summarising the evidence derived from the study of propertiesbelieved to be characteristic of undissociated molecules, one maysay that, apart from the acids, there is virtually no unequivocalevidence of the existence of molecules in solution of " strong "uni-univalent electrolytes at any concentration.The more noteworthy of the attempts to extend the range ofvalidity of the ionic-atmosphere calculations to less dilute solutions,while preserving the principle of complete dissociation, are the so-called " second approximation " of P. Debye and E. Huckel z9 andthe treatment of T.H. Gronwall, V. K. LaMer, and K. Sand~ed.~OThe former of these replaces the point charges of the simple theoryby spheres of finite size with a least distance of approach a. Theintroduction of this parameter into the expression for the logarithmof the activity coefficient has the effect of increasing the activitycoefficient to an extent which increases with the size of a ; that isto say, with ions of finite size the activity coefficient diminishes lessrapidly with increasing concentration than is predicted for point-charge ions. Quantitatively this " second approximation " iscapable of expressing the experimental activity coefficients forelectrolytes with Earge ions up to concentrations of the order ofO-lN, using quite plausible values for a ; on the other hand, forsome electrolytes, such as potassium nitrate and potassium iodate,the expression leads to impossibly small values for a.Thus thesingle auxiliary assumption of a finite size for the ions is seen to beinadequate to account for the facts in more concentrated solution.A more thorough and more complicated extension of the simpletheory is that of Gronwall, LaMer, and Sandved. Their treatmentnot only introduces the least distance of approach, but also takesinto account the further terms of the series for the potential energyof the ion due to the atmosphere, a series of which the simplifiedtreatment neglects all but the first term. The notable featuresof the resulting equation for the logarithm of the activity coefficientare that, for small ionic radii, activity coefficients less than those ofthe simplified theory are predicted, and also that the behaviourof electrolytes like potassium nitrate and potassium iodate isadequately represented up to O.1N-concentrations by postulatingsmall but not impossible values for a.Thus, so far as activity coefficients are concerned, the treatmentof these authors gives an adequate representation of the facts up to0-1N-solutions with the aid of an admittedly complicated equation,which, however, contains only one adjustable parameter a, whosevalues are always physically plausible.When the same treatment29 Physikat. Z., 1923, 24, 185; A., 1923, ii, 469.30 Ibid., 1928, 29, 368; A., 1928, 841“ TRUE ” DEGREE OF DISSOCIATION OF STRONG ELECTROLYTES.25is extended to heats of dilution, as has been done by E. Lange andJ. Meixner,31 it is, however, found to be inadequate to explainthe facts, and, in particular, the a values necessary to account forthe heats of dilution of a series of salts are sometimes graded inmagnitude in the opposite sense to the values necessary to makethe activity coefficients “ fit.”Although neither the “ second approximation ” of Debye andHuckel nor the treatment of Gronwall, LaMer and Sandved (norseveral other attempts in the same direction) has succeeded inaccounting for the behaviour of electrolytes outside the limitingrange of concentration in purely electrical terms, the conclusionmust certainly not be drawn that the postulation of undissociatedmolecules is therefore necessary at these concentrations.The factof the matter is that the difficulties of any complete treatment of theelectrical forces in concentrated solutions are beyond our mathe-matical equipment at the present time. The attempts just describedwere only made possible by concentrating on one or two of the com-plicating factors and neglecting the remainder. Apart from suchfactors as the influence of the electrolyte on the dielectric constantof the solvent and the temperature variation of a, the proximityof the ions in concentrated solution must certainly add to the long-range Coulomb forces between the ions the far from negligible short-range forces generally characterised as “ van der Waals forces.”Pending an adequate mathematical treatment of the problem,there is some justification for regarding the postulation of undis-sociated molecules in such solutions as an unnecessary hypothesis.Mid-way between the purely electrostatic picture of a solution andthe view which assumes the existence of undissociated moleculesis the “ion-association” theory of N.Bjerr~m.3~ He points outthat the Debye-Huckel postulate, that the potential energy of anion is much less than its kinetic energy, is less likely to be true thehigher the valency of the ions, the lower the dielectric constantof the solvent, and the closer the ions can approach one another(i.e., the smaller their radii). He shows that the probability of ax-valent ion being at a distance r from a similar ion of opposites i p passes though a minimum value given by the equationwhere E is the electronic charge, D the dielectric constant of thesolvent, k the Boltzmann gas constant, and 17 the absolute temper-ature.Inside this radius the probability increases very rapidlyowing to the strong attractive forces exerted between the ions.31 Physikd. Z., 1929, 30, 670; A., 1928, 1389.33 Ergebnisse d. exakt. Xaturwiss., 1926, 5, 12526 GENERAL AND PHYSICAL CHEMISTRY. WOLFENDEN :Por aqueous solutions of uni-univalent electrolytes a t 18”, rmin. hasthe value 3.52 A. An electrolyte with ions the sum of whose radiiis greater than this critical value, is treated by Bjerrum as completelydissociated and susceptible to the unmodified Debye-Huckeltreatment.If the sum of the ionic radii is less than rmin.3 Bjerrumarbitrarily divides the ions into two groups, namely, those whosedistance apart is more than rmin., which are assumed to be free, andthose within the minimum distance, which he treats as “ ion-pairs.”The proportion of ion-pairs is calculated by integrating the probabilityfunction over the interval from rmin. down to the sum of the ionicradii.Although the line of demarcation between free and associatedions. is thus drawn at a quite arbitrary point (the probability mini-mum being associated with no physical discontinuity) Bj errumapplies the mass-action law to the equilibrium between ion-pairs andfree ions. The activity coefficient of the ion-pairs is put equal tounity and that of the free ions is calculated from the Debye-Hiickelsecond approximation,” rmin.being put in as the a parameter.In this way a series of degrees of “ ion-association ” are calculatedwhich increase with concentration and also with diminution in theradii of the ions concerned. The over-all activity coefficients maythen be calculated and are found to be in good agreement withexperiment up to concentrations of the order of 0.L” Like theexpression of Gronwall, LaMer, and Sandved (and in contrast tothe “ second approximation ” of Debye and Huckel), Bjerrum’streatment leads to values of the ionic radii which are always positiveand of plausible magnitude.I n spite of its somewhat arbitrary mathematical derivation, thehypothesis of “ ion-association ” has various attractive features.It represents the experimental facts as adequately as the morecomplete mathematical analyses ; it gives a clearer physical pictureof the solution; and it is perhaps worth noting that the possibilityof “ion-complexes” (composed of more than two ions) at highconcentrations in solvents of low dielectric constant offers a possibleexplanation of the increase of equivalent conductivity a t highconcentrations after passing through a minimum as observed byW alden .The “ ion-association ” hypothesis can hardly be said to be oneof complete dissociation, since the ion-pairs of Bjerrum are regardedas temporary juxtapositions of undeformed and completely solvatedions whose equilibrium with “ free ’’ ions is for reasons of expediencytreated as subject to the mass-action law.There remain to be con-sidered two points of view in both of which is postulated an equili-brium of the true Arrhenius type (corrected for activity coefficients)< '' TRUE " DEGRZB OF DISSOCIATION OF STRONG ELECTROLYTES. 27between undissociated molecules and ions subject to the electro-static forces of the Debye-Ruckel limiting equations. The Grstof these is primarily associated with the name of W. Nernst and isbased on a consideration of heats of dilution; the second, due toC. W. Davies and to L. Onsager in the Grst instance, is based onconductivity data.Nernst 33 divides the experimentally observed integral heat ofdilution into two parts; the first of these is the heat absorbed in thedissociation of the un-ionised portion of the electrolyte, and thesecond is the electrostatic heat of dilution of the ionised portion.This leads to the equationv, = - &(1 - a) + E a d Zwhere Q is the heat of ionisation of the molecules, c the concentrationof the solution, oc the true degree of dissociation, and B the numericalcoefficient of the electrostatic heat of dilution (see equation 3 ;p.30). The validity of the mass-action law for the dissociationof the ions being assumed, it is possible by applying the van 'tHoff isochore to the measurements of the heat of dilution of anelectrolyte at two temperatures to evaluate the two unknownsQ and a by a series of successive approximations, and thus to pre-dict the variation of the integral heat of dilution over the wholerange of concentrations.Several approximations and assumptionsare employed ; instead of the theoretical proportionality factorbetween electrostatic heat of dilution and the square root of theconcentration, Nernst equates B to the observed slope for lithiumchloride which is thus regarded as an ideal completely dissociatedelectrolyte ; furthermore, the activity coefficient of the ions is equatedto unity over the complete concentration range ; finally, it is assumedthat the electrostatic contribution to the heat of dilution maintainsits linear relation with the square root of the concentration up tothe highest concentrations involved. In spite of these simplifyingassumptions, it is found that the Nernst equation represents theexperimentally determined heats of dilution satisfactorily up toconcentrations of the order of N / 3 and N .The degrees of dis-sociation of sodium chloride and potassium nitrate in 0-1N-solutionare given as 98.9% and 95.2% respectively at 18". In spite of itsconcordance with experimental facts for the uni-univalent saltsstudied, the Nernst treatment cannot be regarded as entirelysatisfactory since it embodies several assumptions that are certainlyuntrue; it is also a t variance with the individualities in the heatsof dilution of electrolytes (referred to on p. 32) a t very low con-centrations where the undissociated portion, which is roughly pro-a3 2. Elektrochem., 1927, 33, 428; A., 1928, 12728 GENERAL AND PHYSICAL CHEMISTRY.portional to the first power of the concentration, can no longer beof significance.A recent paper by E. Plake,34 in which the heatsof dilution of uni-bivalent and bi-bivalent electrolytes are treatedfrom the Nernst point of view, arrives a t the conclusion that,whereas uni-univalent electrolytes are incompletely dissociated,the electrolytes of higher valency are completely dissociated ; thisinference is so much at variance with accepted views that it canhardly fail to shake one’s confidence in the underlying hypothesis.The derivation of true degrees of dissociation from conductivitymeasurements has been treated by L. On~ager,~5 C. W. D a v i e ~ , ~ ~M. and other workers ; their respective treatments areidentical in principle although the most accurate method is probablythat of Davies, which may be taken as representative of the others.The fall of equivalent conductivity with increasing concentrationis attributed jointly to (1) the decrease in mobility due to electro-static forces as calculated by the Debye-Hiickel-Onsager equationand (2) the diminution in number of the ions free to conduct owingt o the formation of undissociated molecules.Since the first effectis readily calculable, the magnitude of the second can be found.The method of calculation employed by Davies is as follows:Let cc be the true degree of dissociation of an electrolyte, whoselimiting equivalent conductivity is A,, a t a concentration where theequivalent conductivity is A,.Then a is not given by &/Ao butby &/Azy where A, is the sum of the ionic mobilities in the solutionconsidered. Since the concentration of the ions is cA,/A,, the valueof A, is given by the Onsager equation, which for an aqueous solutionof a uni-univalent electrolyte at 25” isA, = A, - (0.22711, + 59-78)dcAC/AzThis is a cubic equation in A, and is solved as such by Wien ; Daviesprefers to evaluate A, by a short series of successive approximations.When A, has been determined in this way, the true degree ofdissociation is immediately evaluated as &/Ax. Davies then appliesthe mass-action law, corrected for the activity coefficients of theions, to the true concentrations of ions ci and undissociated mole-cules c, obtained in this way, and writescFf?/cu = Kthe activity of the undissociated molecules being put equal to unity.The constancy of this relation can be tested directly or graphically34 2.physikal. Chern., 1932, [ A ] , 182, 257.35 Physikal. Z., 1927, 28, 277; A., 1927, 617.3% Trans. Farahy Soc., 1927, 23, 351.37 See H. Falkenhagen, “ Elektrolyten,” p. 299WOLFENDEN : THE THERMOCHEmSTRY OF ELECTROLYTES. 29in the following manner :taking logarithms, we may therefore write the above equation asAt high dilutions - lOgfi = A 6 ;log c?/c, = log K + 2 A f iPlotting log@/c, against fi, we should therefore expect to geta straight line whose slope is 2A and whose intercept on the axisof zero concentration is log R.Davies has evaluated the true degrees of dissociation of a numberof salts in this way, and has obtained corrected mass-action constantswhich are a very marked improvement on the Ostwald ‘‘ constants ”for the same electrolytes.Its extension to non-aqueous solutions,where incomplete dissociation is much more common, is likely to beof great value ; unfortunately, its application is there handicappedby the scarcity of reliable values for A, and by the very small con-centration range over which Onsager’s equation is valid in solventsof low dielectric constant. Although the validity of this methodof determining true degrees of dissociation can only be tested overthe range of concentrations in which Onsager’s equation is applicable,it is important to notice that, provided that a satisfactory constantcan be evaluated for a given electrolyte over this range, the degreeof dissociation can then be found a t higher concentrations frommeasurements of activity alone.The only limit to such an extensionis imposed by the condition that the activity of the undissociatedmolecules must approximate to the concentration. It is unfortunatethat the method does not lend itself to cases where dissociationmust be very nearly complete ; the mode of calculation is susceptibleto considerable error unless the un-ionised fraction is present inappreciable amounts. Thus, in the case of nearly all uni-univalentsalts in water, the un-ionised fraction only becomes measurablea t concentrations where the Onsager equation is inapplicable, andrecourse must be had to an empirical conductivity equationembodyinga viscosity correction.Notwithstanding these limitations and thefact that no physical picture i s afforded of the nature of the “ un-dissociated ” portion of the electrolyte, the Davies method oftreating conductivity data is probably the least equivocal way ofgaining infomtion as to the degree of dissociation of electrolytes.J. H. W.3. THE THERMOCHEMISTRY OF ELECTROLYTES.At the time when the thermochemistry of electrolytes wm lasttouched on in these Reports,38 it was necessary to record a seriousdiscrepancy betwccn the predictions of the interionic attractiontheory concerning the heat of dilution of electrolytes and the38 Ann. Reports, 1027, 24, 2330 GENERAL AND PHYSICAL CHEMISTRY.experimental data available at the time.Theory predicted that theheat of dilution of the ideal electrolyte in aqueous solutions mustbe positive, whereas the measurements then published showednegative heats of dilution for the majority of electrolytes. Precisemeasurements of heats of dilution of electrolytes a t very low con-centrations carried out over the last five years by E. Lange 39 andhis collaborators have served to remove this discrepancy and toconfirm in a general way the interionic attraction theory in thisfield.The heat evolved when a volume of solution sufficient to containone mol. of electrolyte is diluted to infinite dilution is called theintegral heat of dilution and is usually denoted by the symbol Vc.In the ideal electrolyte of the Debye-Hiickel theory this heat effectis due to purely electrostatic forces, and its magnitude may becalculated by the application of the Gibbs-Helmholtz equation tothe electrical free energy of the solution.where QC is the heat of dilution per c.c., and F,, the electrical freeenergy per C.C.of the solution, is negative for all finite concentrationsof the ideal electrolyte and converges to zero as the concentrationbecomes infinitely small. The solution of this equation for a binaryelectrolyte consisting of two x-valent ions leads to the expressionWe thus haveQC = P, - T(aB',/aT), . . . . . (1)Nc2z2 v--- 8xz2E2N (1 + 21 dD) 2/c . . . D 1OOODET D'dT c -where N = Avogadro number,E = electronic charge,II: = Boltzmann gas constant,D = dielectric constant of the solvent,and c = concentration of the solution in mols./litre.Giving the universal constants their numerical values, inserting thedielectric constant of water and its temperature coefficient, and con-verting from ergs to calories, we obtain the expression for aqueoussolutions a t 25" :Vc = + 4 9 0 ~ ~ 6 calories .. . . (3)39 Thirty-six papers have already appeared, of which the last is by H.Hammerschmid and E. Lange, 2. physikal. Chem., 1932, [ A ] , 160, 445 ; A.,913. For summarising paper, see E. Lange and A. L. Robinson, Chem.Reviews, 1931, 9, 89.40 0. Gatty (Phil. Mag., 1931, 11, 1082; A., 1931, 685) and, later butindependently, G. Scatchard ( J . Amer. Chem. SOC., 1931, 53, 2037 ; A., 1931,913) have pointed out that this equation involves the erroneous assumptionthat (dD/dT)v and .,(dD/dT), are mutually interchangeable. The correctedequation includes an extra term involving the thermal expansion of thesolvent ; this term is small for water but of significance in non-aqueous solventsWOLFENDEN : THE THEBJklOOHEHCSTRY OF ELECTROLYTES.31The important features of this expression are (1) that the heat ofdilution (or more precisely the electrostatic contribution to the heatof dilution) is always positive in aqueous solutions-this is equallytrue for virtually all solvents of high dielectric constant (see below) ;(2) that the heat of dilution is proportional to the square root oftha concentration ;(3) that the heat of dilution is identical for electrolytes of the samevalency type.The positive sign of the electrostatic contribution to the heat ofdilution is remarkable. It seems at first sight unreasonable to ex-pect that the dilution of a completely dissociated electrolyte, inwhich the formation of ionic atmospheres is well known to lead to a,predpminance of attractive over repulsive force, should lead to theevolution of heat.The solution of the paradox depends on theforces exerted by the ions on the dipole molecules of the solvent.N. Bjerrum 41 expresses this by saying that the energy absorbed inincreasing separation of the ions with progressive dilution is morethan compensated by that evolved as more and more solvent dipolemolecules give up their kinetic energy by orientation round the ions,Le., that the compensating factor is, in effect, the energy released byincreased " electrostatic solvation." Such a physical picturecannot, of course, be rigidly deduced from the thermodynamiccalculation itself.Examination of the latter shows that the heatof dilution will only have a positive sign when the temperaturecoefficient of the dielectric constant of the solvent has a sufficientlylarge negative magnitude to make the term (1 + T / D . dD/dT)in equation (2) negative. This proviso is equivalent to the conditionthat the negative value of dD/dT must be large enough to cause theelectrical free energy of the solution to increase its numerical(negative) value with rise of temperature (owing to increased electro-static forces between the ions) sufficiently rapidly to cause the term2"(Ue/ljT)v to have a larger numerical value than the term Fe inequation (1). Since dD/dT depends, roughly speaking, on the dipolemoment of the solvent molecules, it is possible to see in 8 qualitativeway how the thermodynamic condition for positive heats of dilutionagrees with Bjerrum's physical picture. An examination of theavailable dielectric constant data shows that TID . dD/dT isalgebraically less than - 1 in the case of all common ionisingsolvents, although the values for some solvents of lower dielectricconstant, such as acetaldehyde42 (D = 21-1, T/D .dD/dT =-0.88)and phosphorus trichlorida" (D = 3.5, T/D . dD/dT = -0.79),41 Z.physika1. Chem., 1926,119,145; A., 1926, 476.ps T.M. Lowry, J., 1932,207; A., 322.P. Drude, ibicl., 1897, 25, 26732 GENERAL AND PHYSICAL CHEMISTRY.lead to negative values of the hypothetical heat of dilution of idealelectrolytes dissolved in such media.The quantitative test of the theoretical expression in any solventis of peculiar difliculty for two reasons. First, it involves themeasurement of temperature changes of the order of a few millionthsof a degree. Secondly, the predicted value of the heat of dilution isextremely sensitive to small errors in the temperature coefficientof the dielectric constant of the solvent, a quantity whose magnitudeis very uncertain; even in water the numerical coefficient of equa-tion (3) is subject to an uncertainty, on this account,of about 10%.Lange and his collaborators have overcome the experimentald8iculties with great skill by developing a differential methodbased on the well-known principle of the twin calorimeter.ADewar vessel is divided into two halves separated by an insulatingdiaphragm containing a thermocouple of 1000 junctions, sensitiveto temperature differences of lo-''. The dilution is carried out inone half of the vessel while the other half, containing solvent only,serves t o balance the effect of the heat of stirring, heat loss due toevaporation, etc. The technique has been refined to the pointwhere heats of dilution can be measured down t o M-con-centration. Precision of this order has enabled them to test thetheoretical equation within the " limiting range " of Debye-Hiickelcalculations.Their measurements cover electrolytes of uni-uni-, bi-uni-, andbi-bi-valency types but have been confined to aqueous solutions.The principal results may be summarised as follows :(1) The integral heat of dilution is invariably positive at lowconcentrations.(2) The integral heat of dilution is proportional to the square rootof the concentration up to M/100 for uni-univalent electrolytesand over a correspondingly smaller concentration range for thehigher valency types.For a minority of salts, such as potassiumnitrate, the range of obedience to the square-root relation is a gooddeal more limited.(3) Within the limits imposed by our uncertainty as to thevalue of dD/dT, the limiting slope of V, plotted against &agreeswith the predicted value.(4) Even at the lowest concentrations experimentally attainable,small but quite definib differences in limiting slope persist amongvarious salts of the same valency type ; this is true of uni-univalentsalts and is more marked with ions of higher valency.The individuality of electrolytes, Le., their deviation from theideal behaviour postulated by the Debye-Huckel theory, seems topersist in their thermochemical properties down to concentrationWOLFENDEN : THE THERMOCHEMISTRY OF ELECTROLYTES.33substantially lower than those a t which activity and conductivitydata suggest virtually ideal behaviour. It is similarly found that a tintermediate concentrations thermochemical differences betweenelectrolytes of the same valency type are much more striking thanthose observed in the activities and conductivities of the sameelectrolytes.W.Nernst44 has sought to account for these deviations by in-complete dissociation of the electrolytes concerned ; his view isbriefly discussed in the section on " the true degree of dissociationof electrolytes " (p. 27). Lange and his associates prefer to lookfor their cause in the simplifying assumptions and second-orderterms of the purely electrical treatment. In particular, they haveexplored the possibilities of three refinements in the simplifiedtreatment. Of these, the &st is the introduction of a series of avalues characteristic of the least distance of approach of the ions,which are no longer assumed to be point charges.The individualvalues that can be given to this added parameter make it possibleto account for differences between electrolytes of the same valencytype. Unfortunately, it is found, not only that the sequence inorder of magnitude of the necessary a values bears no consistentrelationship to the radii of either the ions in the crystal or thesolvated ions, but also that the sequence is in some cases the reverseof that which must be adopted to account for the activity data.The second refinement is the introduction of a term for the temper-ature coefficient of these a values, individual for each electrolyte.This involves a considerable complication in the theoretical treat-ment ; investigation shows that it involves an added negative termwhich is proportional to the first power of the concentration and there-fore unlikely to be of significance at the lowest concentrationsat which the individualities persist.The third and final avenueexplored by Lange is the possible effect of the electrolyte on thedielectric constant of the solvent. Here again the effect is probablyproportional to some higher power than the square root of theconcentration so that its significance will be small a t high dilutions.Furthermore, E. Lange and A. L. Robinson *5 have shown that,although the addition of urea reduces the temperature coefficientof the dielectric constant of water so much as to lead to the predic-tion of negative heats of dilution, when aqueous urea solutions areused as %L solvent the experimentally determined heat of dilutionof potassium chloride in such a solvent is only very slightly differentfrom that of the same salt when dissolved in pure water.The general conclusion to be drawn from the work of Lange and44 W.Nernst, 2. Elektrochern., 1927, 33, 428; A., 1928, 127.4 5 J. Amer. Chem, SOC., 1930, 52, 4218; A., 1931, 42.REP.-VOL. XXIX. 34 GENERAL AND PHYSICAL CHEMISTRY.his collaborators seems to be that, although the positive sign, thevariation with concentration, and the valency effect in the heat ofdilution of aqueous solutions are in harmony with the interionicattraction theory, certain residual individualities persist in thethermochemical properties of electrolytes at high dilutions for whichthe electrostatic theory in its present form is unable to account.Thermochemical measurements are seen to constitute a peculiarlysensitive means of exploring deviations from ideal behaviour inelectrolytes although it is not, at the moment, a t all clear whythis should be so.The reason is perhaps to be sought in thepeculiarly dominant r6le which ion-solvent forces (as distinct fromion-ion forces) play in heats of dilution.J. H. W.4. QUANTUM MECIIANICS AND ELECTROCHEMISTRY.The application of the new ideas of quantum mechanics to electro-chemistry has not been long delayed and some preliminary papersrecently published suggest that they are likely to give us a muchclearer insight into some electrochemical phenomena. The elucida-tion of electrode processes, of which the thermodynamic account isalready eminently satisfactory but whose mechanism has hereto-fore been obscure, is likely to prove particularly valuable.A recent paper by R.W. Gurney46 provides an interestingmechanism for overvoltage as well as sketching a physical pictureof the discharge of an ion a t an electrode; an important featureof Gurney’s mechanism for overvoltage is that the phenomenon isregarded as a primary effect and not in any way due to secondaryeffects such as bubble formation, gas films, or the combination ofdischarged atoms to form molecules.Fig. 1 represents the potential-energy curve of an electron alonga line joining the surface of an electrode of an inert metal t o aneighbouring hydrated cation such as the hydrogen ion.Thehorizontal lines MM represent the occupied electron levels in themetal, 4 being the work function of the metal. On the right is theCoulomb field and vacant electron level of the hydrated ion; owingto the positive heat of hydration of the ion W , the distance (E) ofthis vacant level below the standard level of zero energy is not I ,the ionisation potential of the ion-producing atom, but 1 - W ;E is the energy evolved when the ion is neutralised.In a second paper (ibid.,1932, [A], 136,378; A,, 699) Gurney deals with the relation between the con-tact potential difference at a metal-metal interface and the E.M.P. of thevoltaic cell. His treatment of this subject is interesting but not, however,essentially novel (see, e.g., J. A.V. Butler, Phil. Mag., 1924, 48, 927; A.,1925, ii, 42).4 6 Proc. Roy. SOC., 1931, [A], 134, 137; A., 26WOLFENDEN : QUANTUM' MECHANICS AND ELECTROCHEiVfISTRY. 35Although classical mechanics forbids the transition of an electronover the energy barrier, quantum mechanics represents an electronin the metal by a wave-function which does not end abruptly a tthe surface of the metal but dies away exponentially into thepotential barrier. Corresponding to this there is a finite prob-ability of an electron " leaking through " the barrier from the metalinto a vacant level of eqml energy in the neighbouring ion. In thecircumstances represented in the diagram (corresponding, e.g., to aplatinum electrode dipping in a solution of an acid). neutralisationof the hydrogen ion cannot take place because the vacant level inFIG. 1.I StandardLevel gfISurfBce of metal Nude us of cationLine perpendicdar t o surface o f metalthe ion is higher than the highest occupied electron level in themetal.In order that neutralisation may take place andcurrentmay peas through the electrode, the electron levels in the metalmust be raised by building up a negative (i.e., a " cathodic ") poten-tial in the metal. The negative potential necessary to causecurrent to flow is determined by the condition E >The above picture of the process of discharge of the hydrogenion is over-simplified in so far as (a) the hydration energy is notdefinite but is spread over a series of energy levels correspondingto a series of vibration levels in the hydrated ion, and (b) the metallicelectron levels are not all empty above nor all occupied below.Both of these distributions may be calculated; the former obeys a- EV36 GENERAL AND PHYSICAL CHEMISTRY.Boltzmann distribution, the latter is governed by the Fermi-Diracstatistics.The condition for the passage of a finite current through thecathode with the liberation of hydrogen (or the discharge of anyother cation) is that an appreciable number of high-energy electronsin the metal shall overlap the vacant levels in the positive ion.The variation of this overlap (and the consequent variation incurrent density) with the cathodic voltage and the temperature isthe main object of Gurney’s calculations.Having worked out thetwo distributions indicated above, he has calculated the probabilityof the transition or leakage of an electron across the potentialbarrier from the metal to the ion.By integration of this prob-ability between appropriate limits, the current density a t thecathode is calculated in terms of the cathodic voltage and thetemperature. His result, embodying certain reasonable approxim-ations, islog i = E~ - ‘1 + + log T + constantYkTwhere i is the current density, V the cathodic potential, T theabsolute temperature, k the Boltzmann gas constant, E, - El + ZVcorresponds t o the range of energies over which the probability isintegrated, and y is a small factor greater than unity and, to a firstapproximation, constant. Differentiating with respect to voltageand temperature respectively, we have d log i / d V = ~ / y k T andd log i / d T = (E, - E, - &V)/ykT2 + 1/T.These two equationsare in qualitative agreement with F. P. Bowden’s experimentalobservations : 47(a) that d log i / d V = A/T, where A is independent of the natureof the inert-metal electrode and of whether it is used as anode forthe discharge of oxygen or cathode for the discharge of hydrogenand( b ) that d l o g i / d T = B, where B decreases with increasing V .Furthermore, if y is given the not improbable value of 2, the agree-ment between &/@ and the empirically determined A is excellent.If, in addition, E, - El + EV (which corresponds to the overlap ofenergy levels over which the probability is integrated) is set at thereasonable value of one electron-volt, the temperature coefficient oflog i predicted is in good agreement with the observed values of B.I n this way Gurney has shown that two important characteristicsof overvoltage, vix., the variation of current density with appliedvoltage and with temperature, can be adequately and quanti-tatively accounted for by regarding the determining factor as theA ., 1930, 169.4 7 Proc. Roy. SOC., 1929, [A], 125, 446; A,, 1929, 1391; ibid., 126, 107WOLFENDEN : QUANTUM MECHANICS AND ELECTROCHEMISTRY. 37probability of the quantum-mechanical transition of an electronfrom the electrode to the cation to be discharged (or from the anionto be discharged to the electrode).Another application of quantum mechanics to an electrochemicalproblem is to be found in a paper by L.Farkas 48 on the conductivityof concentrated solutions of sodium in liquid ammonia. It is wellknown that, as the concentration of such a solution increases, theequivalent conductivity a t first diminishes proportionally t o thesquare root of the concentration, corresponding to electrolytic con-duction by sodium ions and probably solvated electrons; at aconcentration about O-lM, the equivalent conductivity passesthrough a minimum and then increases very rapidly until in satur-ated solution the specific conductivity is comparable with that ofliquid mercury. Corresponding to this rise in conductivity, thecontribution of the sodium ions to the carriage of the currentdiminishes rapidly and becomes insignificant in the more concen-trated solutions.Heretofore the rise in equivalent conductivity in concentratedsolution has received only a qualitative explanation which attributesit to the increasing proportion of free unsolvated electrons as theconcentration of sodium in the solution rises.The shift in theequilibrium between free and solvated electrons with increasingconcentration necessary to account for the observed rise in equi-valent conductivity is so great as to render this explanation far fromprobable.Farkas attributes the conductivity in concentrated solution tothe quantum-mechanical transition of electrons between neighbour-ing sodium atoms, which under the influence of an applied potentialgradient will take place more frequently towards the anode thantowards the cathode.Fig. 2 represents the potential-energy curveof an electron relative to two sodium atoms in a uniform potentialgradient such that the anode lies to the left of the figure. I isthe ionisation potential of the sodium atom, d, is the distancebetween the two sodium atoms, and the applied potential gradientis equal to (tanB)/(electronic charge). The probability of anelectron transition in either direction by leakage through the poten-tial barrier can be calculated by the Gamow-Condon-Gurneyformula and expressed in terms of the above quantities togetherwith the mass of the electron (m), the principal quantum number(n), and the orbital radius ( r ) of the outermost electron in the sodiumatom, the concentration of the solution (c), the Avogadro number( N ) , and Planck’s constant (h).By subtracting the two prob-abilities, the excess of electron transitions towards the anode can4 8 2. physikal. Chern., 1932, [A], 161,35538 GENERAL AND PHYSIUAL CHEMISTRY.be calculated, and hence the specific conductivity.approximation the result isTo a firstIf it is now assumed that the sodium atoms are distributed regularlythrough the solution as in a simple cubic lattice,* the distance apartof the atoms dc at a concentration c is given byac = I/VC x 6 x 1020Putting n equal t o 3, T equal to 1-7 x lo-*, and giving the universalFIG. 2.Direction o f (negat;~e)potent/b/gradient-t--constants their numerical values, we obtain the following expressionfor the specific conductivity at concentration c1 4.3 x 1oqqyFK~ = 3.10 x 10l1 * - <IThis equation leads t o a curve of specific conductivity againstconcentration very similar to but slightly steeper than that observedexperimentally.The value of I necessary to give the observednumerical values lies between 9000 and 10,000 calories per mol.;this is about 12 times as small as the ionisation energy in vucuo,whereas the dielectric constant of liquid ammonia is about 22. Inview of the approximate nature of the calculations and the absenceof arbitrary constants, the concordance is as good as could beexpected.If the atoms are distributedover a range of distances apart, the small number of atoms near the minimaldistance will play a dominant part in the quantum-mechanical transitions andthe probability of occurrence of this distance will change too slowly withincreasing concentration to account for the experimental facts.* This assumption is essential to the theoryHINSHELWOOD : CHEMICAL KINETICS.39In spite of the somewhat arbitrary assumption of lattice-likedistribution of' atoms in the solution, as well as the fundamentaldifficulty (which is also met with in the theory of the conductivityof metals) that each atom in the latt'ice is regarded a t one and thesame time as ionised (in order that it may receive an.electron) andun-ionised (in order that it may give up an electron), the quanti-tative success of the calculation is sufficient to make it of greatinterest as an application of quantum mechanical principles toconductivity.J. H. W.5. CHEMICAL KINETICS.The study of chemical kinetics depends essentially upon observ-ation of the progress of chemical reactions with time. Thence,conclusions can often be drawn, on the one hand, about the natureof transiently formed intermediate products, and on the other,about the physical laws determining molecular transformations.In both these respects the application of spectroscopic methods hasyielded information in a much more direct manner than kineticmeasurements could, and, in the second matter, quantum-mechanicaltheories can be of great assistance in predicting which kinds ofatomic and molecular processes are possible or probable. As anexample of the elucidation of reaction mechanisms by spectroscopicmeans, it is enough to refer to the identification of the various atoms,radicals, or molecules concerned in the emission of flame spectra(see p.59). To illustrate the application of such means in thediscovery of the physical nature of molecular transformations, weneed only take the investigation of photochemical primary processes(cf . following section).A theoretical classification of chemical rearrangements or de-compositions, which seems likely to prove of great importance, isthat which distinguishes " adiabatic " from non-adiabatic processes.The former kind occur with an accompanying electron transition,the latter without, and there are important differences betweenthem. The following is an example.According to G. H e r ~ b e r g , ~ ~the molecule of nitrous oxide has a singlet ground state, while N,and 0 would correspond t o a triplet state. Hence, if N,O changesinto N, + 0, there must be an electron transition, in fact theunimolecular decomposition of the nitrous oxide molecule wouldhave to be a " predissociation." It is believed that " radiationlesschanges " of this kind ordinarily occur between states of the samemultiplicity. " Intercombinations " can occur, but with a muchsmaller probability. Thus the life of an activated nitrous oxide49 2. physikal. Chem., 1932, [B], 17, 68; A., 680; cf. also R. Mecke, ibid.,18,53; A., 91540 GENERAL AND PHYSICAL CHEMISTEI’.molecule should be abnorindly long, before chemical transformationtakes place.Nitrous oxide absorbs continuously from 2000 A. to1680 A. and from 1550 A. to the edge of the Schumann region. Itis transparent a t longer wave-lengths, although the energy ofremoval of an oxygen atom is not great. These facts illustrate thenon-dissociability of nitrous oxide into N, and 0 in a primaryphotochemical act. Presumably, we must reckon with the occur-rence of non-adiabatic transformations also in the reactions of morecomplex molecules : some of these changes may be “ forbidden ”or associated with very small probabilities. The modification ofthe transformation probabilities by the “ perturbing ” action ofexternal forces may be one important factor in “catalytic ’)phenomena. But in any example of even moderate complexitya priori calculations are almost hopelessly difficult, so that it isprobable that only direct kinetic experiments can decide howimportant factors of this kind really are.The general theoreticaltreatment of adiabatic and non-adiabatic chemical processes is,however, exemplified in the papers of F. London,50 and of H. Pelzerand E. Wigne~-.~l The latter authors, discussing reactions of thetype A + BC = AB + C, show that the probability of electronicexcitation during the chemical rcaction is small when the lowest“ energy surface ” is far removed from the others. (Diagrams canbe plotted giving the potential energy of the system for all relativepositions of the atoms, as in the work of Eyring and Polanyireferred to in last year’s Report. These are the energy surfaces :there will be a different one for each of the possible states ofelectronic excitation of the system.)In previous reports 52 the question of quantum-mechanicalpassage through energy barriers has been mentioned.It appearsthat usually, or a t any rate in examples of chemical interest,transition probabilities calculated by means of this kind of theorydo not differ very much from the classical probability of passageover the energy barrier. The transition probability contains afactor involving the negative exponential of the mass of the particlepenetrating the barrier, the mass coming in from the mass termin the original Schroedinger equati0n.~3 When the particle is anelectron, the non-classical transition probabilities become very high.When the particle has the mass of an ordinary atom, the classicaland the non-classical probability become much closer.R. P. Bell 545 0 z. Prbysik, 1932, 74, 143; A . , 324.51 2. physikal. Chem., 1932, [B], 15, 445; A., 343.52 Ann. Reports, 1930, 27, 26 ; 1931, 28, 23.53 Cf. Gamow, “ Atomic Nuclei,” Oxford, 1931.54 Proc. Roy. SOC. (in the press)HINSHELWOOD : CHEMICAL KINETICS. 41has pointed out, however, that the hydrogen atom, or proton,occupies an exceptional position, and that, owing t o its small mass,appreciable deviations from classical behaviour may be expected.Among the consequences of these deviations is a departure from theArrhenius equation for the variation of reaction velocity withtemperature, in the sense that a t lower temperature, higher valueswould be found for the reaction rate than those predicted by theequation.As Bell points out, no really suitable data for testingthis exist. Spurious deviations from the Arrhenius equation 55 areof course quite common, so that it may be all too easy to " confirm "the operation of quantum-mechanical factors in this particularfield.From what has been said above about the application of methodsand theoretical ideas more or less connected with spectroscopy tothe problems of kinetics, it might be inferred that the more ordinarymethods of investigation were largely superseded, but this wouldhardly be a well-balanced judgment. The difficulty or evenambiguity of quantum-mechanical calculations in examples whichare not almost ideally simple will probably restrict their functiont o stimulating or interpreting rather than replacing or anticipatingdirect experiment.Moreover, methods which depend upontheoretical calculations or upon spectroscopic identification ofintermediate products can only assist in understanding details ofmechanism, and this knowledge is not of much use unless interestin the descriptive chemistry of the complete process is presupposed.The actual unfolding of phenomena in time has always been con-sidered worth observing for its own sake, whether by the contempla-tion of complex emergent qualities which make the changingpicture of nature as a whole, or by the scientific study of reconditeconstituents of this picture, such as chemical reactions.An interesting piece of descriptive chemistry has been growingup in connexion with reactions in the solid state, the type of changemost convenient for investigation being that where one solid yieldsanother solid and a gas.56 It is not usual that the second solidforms solid solutions in the first.This means that molecules orions of the second are more stable when placed in their own spacelattice than when uniformly disseminated among the molecules orions of the initial substance. Consequently, the chemical changecan take place more easily if there is ready formed some of the55 E.g., those due to the existence of two concurrent reactions with differentenergies of activation.Among systems recently investigated are CuS0,,5H20 + CuS04,H,0 +4H,O, M. L.Smith and B. Topley, Proc. Roy. Soc., 1931, [ A ] , 134,224, A., 26 ;Ag,CO,,"Ag,O + CO,, W. D. Spencer and B. Topley, J., 1929, 2633;Trans. Faraday Soc., 1931, 27, 94.B 42 GENERAL AND PHYSICAL CHEMISTRY.lattice of the reaction product to which fresh elements can attachthemselves. Thus reactions of this kind usually spread fromnuclei. These nuclei seem first to be formed on the surface of thecrystals. The conditions governing their formation are independentof those determining the rate a t which they grow as the newlyformed crystal face advances through the unchanged material.The nuclei can be “poisoned” and prevented from growing bythe action of foreign gases in the system.57 As the chemical changeprogresses, the extent of the interface between original substanceand reaction product alters and the rate of reaction thus varies ina complex manner.The shape of the curve representing the extentof reaction as a function of time depends upon the rate at whichfresh nuclei are formed relative to the rate of growth of existingnuclei. When the change spreads from a limited number of nucleifor each particle of the solid, the rate increases with time in an“ autocatalytic ” manner, and passes through a maximum. It ispossible by careful analysis of the form of the curves to draw con-clusions, on the one hand, about the rate of advance of the crystalface and, on the other, about the kind of nucleation process occur-ring. 58When the rate of advance of the new crystal face is known as afunction of temperature, it is possible to attempt a correlation ofthe absolute rate of reaction and the “energy of activation,” andso to test hypotheses about the mechanism by which the new phasegrows.The complete answer to the question of mechanism hasnot yet been found, but Topley 59 has recently made an interestingexploration of possibilities, and concludes that, for the dehydrationof copper sulphate pentahydrate to monohydrate, “ it appears thatit is just possible to account for the observed rate, if four degrees offreedom in the complex cation are taken into account, and regardedas strongly coupled through the central Cu” ion; in addition, avery rapid redistribution of energy inside the activated complex isrequired.”In a review 6O of chemical kinetics in 1927, reference was made tothe fact that a number of bimolecular reactions in solution proceed5 7 E.g., the silver nuclei in the system Ag,C,O, -+ 2Ag + 2C0, are“ poisoned ” by oxygen.5 s ~ €3.Topley and J. Hume, Proc. Roy. SOC., 1928, [ A ] , 120, 211 (for thedecomposition of calcium carbonate hexahydrate in contact with water) ;R. S. Bradley, J. Colvin, and J. Hume, ibid., 1932, [ A ] , 137, 531 ; A., 1094(for the same system and for the dehydration of potassium hydrogen oxalatehemihydrate).59 Proc. Roy. SOC., 1932, [ A ] , 136, 413; A., 702 (for further references, seethis paper).Go Ann. Reports, 1927, 24, 314UINSHELWOOD : CHEMICAL KINETICS. 43at rates very much smaller than those given by the expression,(number of collisions) x e--E'RT, which predicts the correct orderof magnitude for a considerable number of gas reactions dependingon collisions between fairly simple molecules.At that time thediscrepancy was thought t o be due to a deactivating influence ofsolvent molecules. There proves, however, t o be no such generaldeactivating influence. I n the first place, the decomposition ofchlorine monoxide 61 and the interaction of ozone and chlorine 62have been shown to occur a t newly the same rate in solution incarbon tetrachloride as in the gas phase : thus reactions dependingon the co-operation of two molecules are not necessarily interferedwith by the solvent. Secondly, it has been found that two reactions,namely, the combination of triethylamine and ethyl iodide, and theesterification of acetic anhydride by ethyl alcohol, both of whichare " abnormally slow " to the extent of many powers of ten inhexane or in carbon tetrachloride solution, do not take place anymore rapidly in the gas phase.63 (Indeed, even such reaction asthe vapours undergo may be confined to the glass surface of thevessel.) Thus again it appears that, whatever the anomaly maybe, it is not directly connected with solvent action.It also appearsthat the " abnormally slow " reactions in solution are not neces-sarily the most characteristic. Further investigation of the litera-ture 64 reveals the existence of a considerable number taking placeat about the rate predicted by the simple formula, and of a furtherclass in which the rate is many times greater. To account for theseIatter it is necessary to assume the participation of varying numbersof internal degrees of freedom in the activation mechanism, aswith gaseous reactions of rather complex molecules.What causesunderlie the wide variations on either side of what might be called" standard behaviour " of bimolecular reactions in solution is aninteresting problem, about which various views are possible. Butthe time is hardly ripe for discussing them.Many of the subjects discussed in these reports in the last fewyears are still rapidly developing, and it is impossible to do justiceto more than a quite arbitrarily selected few. H. von Hartel, N.Meer, and M.Polanyi have made an exhaustive study of the inter-action of alkyl chlorides and sodium vapour with the object offinding out how the ease of reaction varies with the structure of the61 E. A. Moelwyn-Hughes and C. N. Hinshelwood, Proc. Roy. SOC., 1931,[ A ] , 131,177.6z E. J. Bowen, E. A. Moelwyn-Hughes, and C . N. Hinshelwood, ibid., 134,211; A . , 2 5 .63 E. A. Moelwyn-Hughes and C. N. Hinshelwood, J., 1932, 230.64 E. A. Moelwyn-Hughes, Phil. Mag., 1932, [vii], 14, 112; A., 916; J.,1932, 95; A., 233; Chm. Reviews, 1932,10,24144 GENERAL AND PHYSICAL CHEMISTRY.chloride.65 As is well known, Polanyi found that in many reactionsbetween alkali metals and halogen compounds, nearly every col-lision led to reaction, ie., that the heat of activation is zero, or, inother words, that there is no " inertia." Later, he discovered thatthere is an increase in inertia as the series methyl iodide, bromide,chloride, fluoride is traversed.The following general rules now seemto emerge : there is a decrease in inertia with increasing length ofthe hydrocarbon chain, with passage from primary through secon-dary t o tertiary compounds, with increase in the number of chlorineatoms present, and with introduction of a carbonyl group. Adouble bond on the carbon atom bearing the chlorine hindersreaction, while one on the next carbon atom decreases the inertia.In another paper, N. Meer and M. Polanyi 66 make a comparisonof these structural influences in the gaseous reactions with thosefound for a variety of organic reactions in solution : in a generalway a parallelism appears, which is very suggestive.The number of known unimolecular gaseous reactions increasessteadily, as was only to be expected as soon as the idea of exploringthe unlimited field of organic substances arose.Perhaps the mostinteresting of these recently investigated is the decomposition ofethyl bromides6'The first of the organic unimolecular gas reactions to be foundwas the decomposition of acetone. There has always been somediscussion about the chemical step's in this reaction. The firstsuggestion was that carbon monoxide separates from the molecule,leaving two methyl residues, the interaction of which determines theother products. Subsequently, it has been maintained that thedecomposition must take place by way of keten formation.Itnow appears 68 that when acetone vapour is passed through a tubeat 800-1000", methyl radicals can be detected by the Panethmetal mirror method. It even seems that the temperature coeffi-cient of the rate of decomposition into methyl radicals is about thesame as that of the rate of the ordinary thermal decomposition.Thus the idea of a primary splitting into CO and 2CH3 seems, afterall, to have something t o be said for it.Some years ago Wulf and Tolman concluded, on energetic grounds,that the decomposition of ozone could not take place by the Jahnmechanism 0, =+= 0, + 0, 0, + 0 = 20,. Much more reliablevalues for the heat of dissociation of oxygen are now available, and,65 2.physikal. Chem., 1932, [B], 19, 139.66 Ibid., p. 164.67 E. L. Vernon and F. Daniels, J . Amer. Chem. SOC., 1932, 54,2563; A.,F. 0. Rice, W. R. Johnston, and B. L. Evering, ibid., p. 3629; A.,815.1108HINSHELWOOD : CHEM’ICAL KINETICS. 45in point of fact, are much smaller than was formerly supposed.Recalculation 69 using the newer values rehabilitates the Jahnmechanism as a t least an energetically possible one. It may besaid, in general, that the decrease in the accepted values for theheats of dissociation of the simpler diatomic molecules places anumber of kinetic problems in quite a new light, and some reorganis-ation of our views on molecular decompositions in thermal reactionsmay soon be occurring.From the nature of the method employed in its investigation,the dissociation of nitrogen tetroxide into the dioxide during thepassage of sound waves is specially interesting.According toW. T. Richards and J. A. Reid,70 the velocity constant a t 25” and260 mm. is about 4.8 x lo4, while P. D. Brass and R. C. Tolman 71give 2-8 x lo4 sec.-l at 25” and 1 atmosphere. The activationenergy appears to approximate to the heat of dissociation of thetetroxide, as would be expected.Finally, before we turn to the consideration of photochemicalreactions, brief reference may be made t o recent work on chainreactions, and in particular to the study of the remarkable phe-nomenon of explosive combination between two critical pressurelimits. The work of different investigators can be correlated muchmore easily if, in applying the branching-chain hypothesis, werecognise that the conditions necessary for the actual starting ofchains may be quite independent of those which govern theirpropagation through a gas mixture.72 There is in a rough way ananalogy between this and the phenomenon of change of state, wherethe presence of nuclei may be necessary, but where the rate of growthof the nuclei depends only upon the temperature and pressure orcomposition of the surrounding material.Sometimes the firstcentres from which a branching-chain explosion develops are formedon the wall of the vessel by a heterogeneous reaction.73 If the cata-lytically active parts of the wall are poisoned the chains cannotstart. The system is then in a ccmetastable” state.74 Given,however, that some chains do start, the condition for their branch-ing may be determined entirely by the temperature and compositionof the gas mixture, as it appears to be in the neighbourhood of“ upper limits.”The initiation of chains by surface reactions has been studied byH.W. Melville and E. B. Ludlam 75 for the case of phosphorus69 0. R. Wulf, J . Arner. Chem. Soc., 1932, 54, 156; A., 344.70 Ibid., p. 3014; A., 916. Ibid., p. 1003; A., 474.72 G. Hadman, H. W. Thompson, and C . N. Hinshslwood, Proc. Roy. SOC.,73 H. N. Alyea and F. Haber, see Ann. Reports, 1930, 27, 45.74 See (72). T 5 Proc. Roy. Xoc., 1932, [ A ] , 135, 315; A., 477.1932, [ A ] , 138,29746 GENERAL AND PHYSICAL CEEMITPRY.vapour and oxygen and by A.Ritchie and Ludlam for sulphur andoxygen. The initiation of explosion in hydrogen-oxygen mix-tures by the introduction of artificially produced hydrogen atomshas been studied by P. Haber and F. O~penheimer.~~ The influenceof inert gases on the diffusion of chain-carrying species t o the wallhas been further investigated by H. W. Melville,78 by A. Ritchie,E. R. H. Brown, and J. J. M ~ i r , ' ~ and by H. W. Thompson,8o andothers, the results being on the whole in agreement with whatmight be expected theoretically. The slow oxidation of moistcarbon monoxide has been studied by G. Hadman, H. W. Thompson,and C. N. Hinshelwood,81 who find evidence that chains of greatlength, initiated by hydrogen from the water-gas reaction, arepropagated.From a more general point of view, it should be mentioned thatalternatives to the chain theory of reactions showing explosionlimits are not being ignored.The problem of how far it wouldbe possible to construct a purely thermal theory of the whole groupof phenomena is being explored. Preliminary discussions of thismatter have been published.B2 On the whole, it appears t o thereviewer that a t the present moment the chain theory is the mostconvenient and satisfactory, though the alternatives are not con-clusively disposed of and may still prove to have important elementsof truth in them. (2. N. H.6. PHOTOCHEMISTRY.Technique.-The advent of the spectroscopist in the field ofphotochemistry has emphasised the need for more precise techniquein the examination of photoreactions, particularly in connexionwith the use of monochromatic illumination and very exact quantum-efficiency measurements. Thus, much attention has been given tothe construction of suitable light sources, monochromators, and tomethods of measurement.F. B. Bowden and C. P. Snow 83have used a simple type of large monochromator, constructed,however, of quartz crystal parts of a, size extremely difficult toobtain. F. Daniels and L. J. Heidt 84 describe a much more elabor-ate type of monochromator with optical parts of fused quartz, to be7 c Proc. Roy. SOC., 1932, [ A ] , 138, 635.7 7 2. physikal. Chem., 1932, [B], 16, 443; A., 576.78 Trans. Faraday SOC., 1932, 28, 308, 814; A., 701.T9 Proc.Roy. SOC., 1932, [A], 137, 511 ; A., 1093.Trans. Paraday SOC., 1932, 28, 299; A,, 701.Proc. Roy. Soc., 1932, [ A ] , 137, 87.*2 C. N. Hinshelwood, Trans. Paraday SOC., 1932,28, 184; see also (72).83 Nature, 1932, 129, 720; A., 656.8 2 J . Amer. Chem. SOC., 1932, 54, 2381, 2384BOWEN : PHOTOCHEMXSTRY. 47used in conjunction with a new type of mercury lamp of very highintrinsic intensity. 85 With such lamps and the monochromator theemission lines in the ultra-violet can be isolated with an intensityample for photochemical work, though the shorter wave-lengthssuffer through absorption by the fused quartz. Similar intensitieswithout such good monochromatism of the ultra-violet mercurylines can be obtained from an ordinary mercury lamp with con-denser-f3ters.8G Accurate calibration of such ultra-violet light isbest performed by actinometry,s7 for the surface thermopile has beenshown to be subject to large errors in ordinary use.S8 H.Klumband T. Haase 89 have shown that glass windows lop thick are astransparent as quartz to the ultra-violet, and can be made strongenough to be useful in photochemical work. The most suitablelight source for the region about 2000B. is the condensed sparkdischarge. describe a device forensuring the constancy of this source, for which monochromatismcan be obtained by means of “focal isolation.” 91 Very intenselight of shorter wave-lengths (1469-1295 A;) can now be obtainedfrom a new rare-gas lamp.92Predissociation and Photodissociation (see Ann.Reports, 1930, 27,21).-The most important photochemical problem of the moment isthe elucidation of the mechanism of the photoreactions of simplemolecules in the gaseous state by the correlation of photochemicaldata with spectral observations. It has generally been assumedthat a considerable change in the quantum efficiency of a photo-reaction, and possibly in the nature of the products formed, wouldoccur as the wave-length of the exciting light passes from one sideto the other of spectral thresholds (predissociational or photo-dissociational) .93 I n the case of nitrogen dioxide the spectralpredissociation threshold a t 3800 A. is associated with a veryG. S. Forbes and F. P. Brackett85 See also P. A. Leighton and F. E. Blacet, J . Amer.Chem. Soc., 1932, 54,For capillary lamps containing Bi, Cd, 3165; and R. H. Crist, ibid., p. 3939.Pb, T1, and Zn, see R. H. Hoffman and F. Daniels, ibid., p. 4226.86 E. J. Bowen, J., 1932, 2236; A., 1013.8 7 G. S. Forbes, G. B. Kistiakowsky, and L. J. Heidt, J . Anzer. Chem. SOC.,1932, 54,3246; A., 1013 ; W. G. Leighton and G. S. Forbes, ibid., 1930, 52,3139; A., 1930, 1260.8 8 P. A. Leighton and W. G. Leighton, J . Physical Chem., 1932, 36, 1882;A., 924.8g 2. Physik, 1932, 76, 322.s1 E. 0. Wiig and G. B. Kistiakowsky, ibid., 1932, 54, 1806; A., 705.92 P. Harteck and F. Oppenheimer, 2. physikal. Chem., 1932, [B], 16, 77.93 G. Herzberg, Trans. Faradccy SOC., 1931,27, 378 ; R. Mecke, ibid., p. 359 ;A., 1931, 1136; see also “ Discussion on the Critical Increment of Homo-geneous Reactions,” Chem.Soc., Dee., 1931, pp. 15-21? 50-61.J . Amer. Chem. SOC., 1931, 53, 397348 GENERAL AND PHYSICAL CHEMISTRY.striking photochemical threshold,94 but more recently examinedreactions have not shown such simple behaviour. The absorptionspectrum of chlorine dioxide exhibits a predissociation threshold a t3753 A., and though precise measurements of the rate of photo-decomposition in the gaseous state are difficult to make owing tothe variable effects of secondary reactions, there does not appear tobe a change in the quantum efficiency as the threshold is crossed.g5Experiments on chlorine dioxide in solution indicate that a photo-chemical threshold does exist on the long-wave side of the spectralone a t a distance from it farther than would be expected from themere influence of the solvent .96 Contrary to earlier expectation^,^^no marked photochemical thresholds associated with the spectralpredissociation limits have been €ound for the photodecompositionof aldehydes.Working with gaseous formaldehyde, which showsa predissociation limit at about 2750 pi., R. G. W. Norrish andF. W. Kirkbride 97 found no change either in the quantum efficiencyof photodecomposition or in the nature of the products in spectralregions on each side of the threshold. The products were found tobe H, + CO, and the quantum efficiency unity-facts which do notagree with the older view that the photoreaction is essentiallyH,CO + hv+ H,COx+ H + HCO. The results of P.A. Leightonand F. E. Blacet 98 are similar. They studied the photodecom-position of propionaldehyde in monochromatic light from 3130 to2537 A. This wave-length range brackets a spectral threshold atabout 3250 A. between a predissociational absorption spectrum anda continuous one.* They confirmed earlier work on aldehydes,that two photoprocesses occur, ( a ) decomposition, and (b) polymeris-ation; that the decomposition process is chiefly of the typeRHCO -+ RH + CO, accompanied by the formation of only a smallamount of hydrogen and the hydrocarbon R,; and that, while thedecomposition is unimolecular, the polymerisation is bimolecular.The quantum efficiencies of dissociation and of polymerisation wereseparately estimated ; the former, independent of pressure, variedfrom 0.5 to 1.0 between 3130 and 2537 B., while the latter, dependingdirectly on the pressure, reached values of 0.7 a t 200 mm.pressurein the same spectral range. At high pressures, therefore, the total* The threshold between the predissociational and fine-structure spectrum94 R. G. W. Norrish, J., 1929, 1158, 1604, 1611 ; A., 1929, 893, 1022.g 5 W. Finkelnburg and H. J. Schumacher, 2. physikaZ. Chem., BodensteinFestband, 1931, 740; A., 1931, 1210; J . W. T. Spinks, J . Amer. Chem. SOC.,1932, 54, 1689; A., 581.is unknown for this aldehyde.g 6 E. J. Bowenand W.M. Cheung, J., 1932,1200; A., 581.9 7 J., 1932, 1518; A., 706.g 8 J . Atner. Chem. SOC., 1032, 51, 3163; A., 1006BOWEN : PHOTOCHEMISTRY. 49quantum efficiency attains values well above unity, and further,fluorescence of the vapour was observed, indicating the productionof non-dissociating excited molecules.99 These facts go to showthat the original application of the theory of predissociation tophotochemistry was too simplified.In an important paper on thepredissociation of polyatomic molecules, J. Franck, H. Sponer, andE. Teller 1 provide an explanation of many of the difficulties. Inthe original theories of predissociation the following considerationswere not taken into account :(1) Certain apparent spectral predissociation limits are notassociated with unimolecular decompositions but are caused by theabnormal broadening of the rotational lines through collisions, i.e.,collisions cause the transformation of the excited molecules intoanother neighbouring state whose potential energy-distance curvedoes not cut that of the first.The so-called predissociation limitof sulphur dioxide at 2800-2600 A. is of this type, and this explainswhy this gas does not undergo photochemical change until the higherpredissociation limit a t 1950 A. is approached,2 and why fluores-cence is observed in it a t about 2000 A.(2) When account is taken of the vibrational and rotational energyof the products of the predissociation of polyatomic molecules, anexplanation is provided of the fact that in such cases the spectrallimit is not sharp ; e.g., for NO, the lower limit reaches from 4000 to3000 A. The exact value of a recorded limit thus varies with theexperimental ccnditions of its observation.(3) Predissociation can be induced or increased by collisions insome cases; e.g., deviations from Beer’s law occur in Br, and NO,vapour,3 andiodine atoms are detectable in I, vapour at wave-lengths less than 5100 A.if argon is present, the argon simultaneouslyquenching the fluorescence of the higher vibrational states of the I,molecule.4(4) Predissociational and photodissociational processes, and prob-ably, in general, non-dissociating and dissociating processes, ofactivation can interpenetrate one another, as in the case of iodinechloride.The sum total of these considerations shows that great care mustbe used in interpreting spectral limits, so much so that, instead of99 G.+ Herzberg and K.Franz (2. Physik, 1932, 76, 720; A., 896) have alsoobserved fluorescence of formaldehyde vapour.1 2. physikal. Chem., 1932, [B], 18, 88; A., 896.(Frl.) G. Kornfeld and E. Wecgmann, 2. Elektrochern., 1930, 36, 789; A . ,1930, 1383; K. Wieland, Nature, 1932, 130, 847.3 V. Kondrathev and L. Polak, 2. Physik, 1932,76,386; A., 791.* L. A. Turner, Physical Rev., 1932, [ii], 41, 627.W. G . Brown and G. E. Gibson, ibid., 40,520; A., 79150 GENERAL AND PBPSICAL CHEMISTRY.spectroscopy providing an easy answer t o photochemical problems,it now seems that the photochemist may be able through refinedwork to help the spectroscopist.A number of reactions of the dissociation type have been studied,and mechanisms proposed for the total change in different cases,including the photodecomposition of chlorine monoxide,6 of ozone inred and ultra-violet light ,7 the alkyl iodides,* hydra~ine,~ phosphineloand carbonyl sulphide.ll The mechanism of decomposition of theammonia molecule has been thoroughly investigated,12 the smallquantum yield being due to back reaction,13 and traces of hydrazinebeing also formed.l4Chain Reactions and Photosensitisation.-The photoreactionbetween hydrogen and chlorine continues to receive attention.The hydrogen-atom concentration during reaction has been estim-ated by making use of the two forms of hydrogen.15 Its temper-ature coefficient has been investigated.16 An important newobservation which explains certain of the baffling features of thisreaction has been made by R.W. G. Norrish and M. Ritchie.17By the use of a light-absorption technique for following thereaction, they have shown that the hydrogen chloride formedexerts a large inhibiting effect. New results fail to confirmearlier work on the inhibiting effect of drying.17a Calculationsbased on wave-mechanics indicate that when halogens are dis-sociated by light the free atoms combine with other moleculesW. Finkelnburg, H. J. Schumacher, and G. Stieger, 2. physikal. Chenz.,1031, [B], 15, 127; A . , 227.7 H. J. Schumacher and U. Beretta, ibid., 1932, [B], 17, 405, 417; A.,820.8 G. Emschwiller, Compt. rend., 1931,193, 1003 ; Ann. Chim., 1932, [x], 17,413 ; A., 29,706 ; W. West and (Miss) B. Paul, Trans. Faraday SOC., 1932,28,688; A., 1007.9 R.R. Wenner and A. 0. Beckman, J . Amer. Chem. SOC., 1932,54,2787 ; A , ,918.lo H. W. Melville, Nature, 1932, 129, 546; A., 479.11 W. Lochte-Holtgreven, C. E. H. Bawn, and E. Eastwood, ibid., p. 869 ;l a E. 0. Wiig and G, B. Kistiakowsky, J . Amer. Chenz. SOC., 1932, 54, 1806 ;13 H. W. Melville, Trans. Faraday SOC., 1932, 28, 885.14 G. R. Gedye and E. K. Rideal, J., 1932, 1160; A., 581.1 5 K. H. Geib and P. Harteck, 2. physikal. Chem., 1931, [B], 15, 116; A . ,l 6 E. Hertel, ibid., p. 325; A., 348.17 Nature, 1932, 129, 243 ; A., 348.17a W. H. Rodebush and W. C. Klingelhofer, Proc. Nut. Acad. Xci., 1932, 18,A., 820.A., 705.237.531 ; A. J. Allmand and H. C. Craggs, Nature, 1932, 150, 927BOWEN : PHOTOCHEMISTRY. 51giving, e.g., C13;18 a t the same time, the heats of activation of thereactions :C13 + H2+ (3, + HC1 + HH + C1, + H2-+ 2HC1+ HC1+ H2O + H2-> H a + H20 + Has estimated by the methods of wave-mechanics are such that noneof them is likely to occur in the hydrogen-chlorine photoreaction.19The photochlorination of tetrachloroethylene is strongly inhibitedby oxygen, and in presence of excess of the latter substancethe chief products are trichloroacetyl chloride and carbonyl chloride.20Further study of the chlorination of such hydrogen-free moleculesin the presence and absence of oxygen is likely to clear up manydifficult points in the mechanism of chlorination processes.Chainmechanisms for the photosensitised decompositions by chlorine fornitrogen trichloride21 and of ozone22 have been proposed toexplain the experimental results.Miscellaneous Photochemical Reactions.-A surprising observationof importance in theories of autoxidation is that illumination ofoxygen-free alkali sulphite solutions results in the liberation ofgaseous hydrogen.23 The photochemical decomposition of organicacids in the vapour state and in solution appears to be not a simpleprocess.24 In the photo-oxidation of aliphatic alcohols by acidsolutions of dichromate the photo-active ion is HCrO,’, and theprimary reaction probably gives aldehyde and quadrivalentchromium.25 I n marked contrast to this result, the photo-oxidationof quinine by dichromic acid is governed by the light absorption ofthe quinine molecule.26 Two reactions, whose rates have earlierbeen found to vary as the square root of the light intensity, can bysimplification of the conditions be made to obey the equivalence law.l8 G.K. Rollefson and H. Eyring, J . Amer. Chem. SOC., 1932, 54, 170; A.,l9 G. E. Kimball and H. Eyring, ibid., p. 3876.2o R. G. Dickinson and J. A. Leermakers, &bid., p. 3852.21 J. A. G. Griffiths and R. G. W. Norrish, Proc. Roy. SOC., 1931, [ A ] , 130,22 A. J. Allmand and J. W. T. Spinks, J., 1932, 599; A., 348.23 F. Haber and 0. H. Wansbrough-Jones, 2. physikal. Chem., 1932, [B], 18,24 L. Farkas and 0. H. Wansbrough-Jones, ibid., p. 124; A., 1006; W. C .25 E. J. Bowen and J. E. Chatwin, J . , 1932, 2081; A., 1006.26 G. S. Forbes, L. J. Heidt, and C. G. Boissonnas, J .Amer. Chem. SOC.,1932, 54,960; A., 480; R. Luther and G. S. Forbes, ibid., 1909,31, 770; A.,1909, ii, 632.348.591 ; 1932, [ A ] , 135,69; A . , 349.103; A., 1006.Pierce and G. Morey, J . A m r . Chem. SOC., 1932, 54, 467; A., 48052 GENERAL AND PHYSICAL CHEMISTRY.The photolysis of hydrogen peroxide solutions, normally complex,27becomes simple (quantum efficiency unity) in ultra-violet light ofvery high intensity,28 and by dilution with sufficient carbon tetra-chloride the chain reactions in the photobromination of cinnamicacid 29 also can be suppressed to give a quantum efficiency of unityto the reaction.30 The quantum yields of the photopolymerisationof acetylene 31 and of cyanogen 32 and of the photodecomposition ofpotassium persulphate solutions,33 of ethyl diazoacetate,w and ofchl~roform,~~ and of the photobromination of benzene 36 havebeen measured, and observations have been made relating tothe photochemical interaction of acetylene and water,37 of carbonmonoxide with ammonia and amine~,~* and of chlorine withbenzene.39The question of the production of formaldehyde and carbo-hydrates photochemically in vitro from solutions of carbon dioxide inwater 4O has received attention, and the consensus of opinion nowis that no procedure yet published enables the conditions for thereported formation of these substances to be reprod~ced.~~E.J. B.7. FLAMES AND THE MECHANISM OB CHEMICAL CHANGE.The subject of flames has claimed renewed attention in the pastfew years, and the inferences which can be drawn from the more2 7 F.0. Rice and M. L. Kilpatrick J . Physical Chem., 1927, 31, 1607 ; A .1927, 1154; A. J. Allmand and D. W. G. Style, J., 1930, 596, 606; A., 1030,715; M. Qureshi and M. K. Rahman, J . Physical Cheni., 1932, 36, 664.28 L. J. Heidt, J . Amer. Chem. SOC., 1932, 54, 2840; A . , 918.20 A. Berthoud and J. Bhraneck, J . CI~irn. physique, 1927, 24, 213; A . ,3 O W. H. Bauer and F. Daniels, J . Amer. Chem. SOC., 1932,54,2564; A . , 821.31 S. C. Lind and R. Livingston, ibid., p. 94; A . , 349.32 T. R. Hogness and L. Ts’ai, ibid., p. 123 ; A . , 349.33 R. H. Crist, ibid., p. 3939.34 E. Wolf, 2. physikal. Chem., 1932, [ B ] , 17, 46; A . , 706.35 D. G. Hall, J . Amer. Chem. SOC., 1932, 54, 33; A ., 349.36 E. Rabinovitsch, 2. physikal. Chem., 1932, [ B ] , 19, 190.3’ R. Livingston and C. H. Schiflett, J . Physical Chem., 1932, 36, 750.38 H. J. EmelBus, Trans. Faraday SOC., 1932, 28, 89; A . , 349.39 C . E. Lane and W. A. Noyes, J . Amer. Chem. SOC., 1932,54,161; A . , 349.40 Cf. Ann. Reports, 1927, 24, 39, 225.4 l J. Bell, Trans. Faraday Soc., 1931, 27, 771; A., 29; Nature, 1932, 129,170; A , , 237; G. Mackinney, J. Arner. Chem. SOC., 1932, 45, 1688; F. P.Zscheile, jun., ibid., p. 973 ; A . , 480 ; G. Mezzadroli and E. Vareton, Atti R.Accad. Lincei, 1931, [vi], 14, 347 ; A., 237 ; N. R. Dhar and A. Ram, Nature,1932, 129, 205 ; A., 349, 706 ; M. Qureshi and S. S. Mohammad, J . PhysicalChem., 1932,36, 2205 ; A., 1006.1927, 528THOMPSON: FLAMES AND MECHANISM OF CHEMICAL CHANGE.53recent lines of investigation, in particular with regard to the mechan-ism of chemical change, are already extensive, and promise tobecome more so.Essentially, developments have occurred in three directions.First, further data and hypotheses are available concerning themore purely physical properties of flames, such as their velocitiesof propagation and temperatures, and the function of chargedparticles detected in them ; whilst the conductivity of flames hasbeen studied both experimentally and theoretically. Secondly, theinvestigation of the so-called '' highly dilute " flames, such as areproduced when alkali-metal vapours are introduced into halogensa t low pressure, has led to a closer insight into certain elementaryreactions between atoms and molecules.This work is highlyimportant since modern theories of the forces between atoms andmolecules make a calculation of the heats of activation of suchprocesses a priori The manifold occurrence of " ele-mentary processes " in gaseous chain reactions, both thermal andphotochemical, has moreover made it the more desirable that theyshould be thoroughly understood. Thirdly, the radiation emittedfrom flames of various types has been examined with modern refinedtechnique by many workers, in the infra-red and also in the visibleand ultra-violet regions. Experiments on the infra-red emissionoffer a means of detecting any fundamental changes in themechanism of a reaction with alteration in conditions ; the examplemost studied in this way has been the oxidation of carbon monoxide.The examination of the visible and ultra-violet spectra has led tothe detection of " flame-carriers '' : in particular, the occurrence ofband systems indicates the existence of molecules, which, thoughnot capable of chemical isolation, are present transitorily at leastin excited states in the flames.These products are the activespecies essential for the continuance of the respective reactions,and can be identified with the intermediate products in chainprocesses. Inferences may thus be drawn about the mechanismsof those oxidation processes in which the flames have been studiedin this way. There are, however, almost always unavoidable com-plications which make this procedure questionable, although itappears likely to become very useful in the future.Evidence concerning the ionisation in flames and its bearing uponchemical reactions has been summarised in earlier reports.43 F.Haber,4* from a study of the deformation of the explosive zone and42 Cf.Ann. Reports, 1931, 28, 19.43 E. I(. Rideal, ibid., 1928, 25, 335; C. N. Hinshelwood, ibid., 1927,44 Sitzungsber. Preuas. Akad. Wiss. Berlin, 1929, 11, 162; A., 1929, 771.24, 31654 GENERAL AND PHYSICAL CHEMISTRY.the effect on the velocity of flame propagation when gaseousexplosive mixtures are passed through a wedge-shaped condenser,concludes that uncharged radicals and not electrical particles areresponsible for the process of combustion and especially for thepropagation of ignition.These uncharged radicals can be producedwith less expenditure of energy than the charged ones, and oiilyin the case of C-C and C-H, which have relatively low ionisationpotentials, is there an appreciable splitting into ions. A. E.Malinovski and F. A. Lavrov 45 have examined the influence of anelectric field on the velocity of propagation of the flame in explosivemixtures of various hydrocarbons with air, and find that thediminution in this speed which is observed in the vicinity of theregion of maximum conductivity is accentuated by increase in thecarbon content of the substances involved. According to theseobservers, this result agrees with Ilaber’s theory, the ionisation ofG-C and C-H radicals giving rise to the phenomena observed.Thefailure to obtain a positive effect of the field in hydrogen-oxygenmixtures was considered as substantiating evidence. W. M.T h ~ r n t o n , ~ ~ on the other hand, using methane-air mixtures, findsan increase in flame speed in the electric field, and suggests anexplanation based upon considerations of the internal energy ofthe “ molecular complexes ” said to be produced in the wave-front.Several series of facts are cited in support of the somewhat elaboratehypothesis, but the complications are rather serious. B. Lewis 47has also studied this question and emphasises the importance ofpositive ions in the maintenance of flames. He suggests a possibleexplanation of the discrepancy between the results of Thornton onthe one hand and of Malinovski and Lavrov on the other.H.A. Wilson48 summarises the data and discusses the variousmatters relating to the electrical conductivity of flames from atheoretical standpoint.Photographic measurements on the propagation of flame inelectric fields have also been made by E. M. Gu6nault and R. V.Wheeler.49 Some interesting results are described by H. F. Cowardand F. J. Hartwell 5o on the uniform movement of flame in methane-air mixtures using a series of vessels differing in diameter. Themaximum speed for uniform motion of the flame in a mixture ofgiven composition is markedly decreased with decreasing vesseldiameter. The relationship between the velocity V and diameter D4 6 2. Physik, 1930, 59, 690; A., 1930, 424.46 Phil.Mag., 1930, [vii], 9, 260; A., 1930, 708.4 7 J. Amer. Chem. Soc., 1931, 53, 1304; A., 1931, 689.4 8 Rev. Mod. Physics, 1931, 3, No. I, 156.49 J . , 1931, 195; A,, 1931, 313. J., 1932, 1996THOMPSON : FLAMES AND MECHANISM OF CHEMICAL CHANGE. 55is not simply of the type V = cD~, c and k being constants, but ismore complex. Several other determinations of flame speeds havebeen made,5I and a new method is described by C. Becker andK. Vogt 52 employing a system of rotating mirrors.Flame temperatures form the subject of several other papers.G. W. Jones, B. Lewis, J. €3. Friauf, and G. St.J. Perrott 53 haveemployed the spectral line reversal method to moist hydrocarbon-air mixtures, and find that the mixtures affording the maximumflame temperature contain less hydrocarbon than those affordingthe maximum flame speed of uniform movement.Employing theaccepted values for the specific heats of carbon dioxide and hydrogen,the degrees of dissociation of carbon dioxide and of water, and theheat of dissociation of the hydrogen molecule, G. Ribaud 54 calculatesthe flame temperatures in burning carbon monoxide or hydrogen.Finally, P. J. Daniell 55 obtains a theoretical connexion betweenvelocity of flame, velocity of reaction, specific heat, density, andconductivity of gaseous explosive mixtures.“ Highly diluted flames ” have been mentioned previously inthese Reports.56 Summaries of the work so far carried out, withdiscussions of its theoretical significance, have been published byM.Polanyi57 and G. Schay.58 The main point in the study ofthese “ cold ” flames is that they provide a means of investigatingreactions which proceed a t extremely high velocity, i.e., atalmost every collision of the reactants without requiring heat ofactivation.The view became generally accepted that atomic reactions haveno inertia; in other words, in the exothermic direction they haveno heat of activation. This conclusion was apparently confirmedin the reactions found to be the basis of the highly diluted flames.From measurements on the distribution of light and wall-precipitateand of the “light efficiency,” under different conditions of mixingof the reactants in the long reaction tube, the mechanism of theprocesses occurring was elucidated.The following are examples61 W. Payman andR. V. Wheeler, J., 1932, 1835; 0. C. de C. Ellis, J. SOC.s2 2. Physik, 1932, 75, 894; A., 701.53 J . Amer. Chem.Soc., 1931,53, 869; A., 1931, 572; cf. also A. L. Loomis54 Compt. rend., 1930, 190, 369; A., 1930, 418.55 Proc. Roy. Soc., 1930, [A], 128, 393; A., 1930, 424.5 6 E. K. Rideal, Ann. Reports, 1928, 25, 334; C. N. Hinshelwood, ibid.,5 7 ‘‘ Atomic Reactions,” London, 1932 ; cf. also Naturwiss., 1932, 20, 289 ;6 8 Hochverdiinnte Flammen,” Portschr. Chem. Physik, 1930, 21, 1.Chem. I n d . , 1931, 50,403; A., 1931, 1371.and G. St.J. Perrott, B., 1928, 881.1930, 27, 20; 1931, 28, 47, where detailed references are given.A., 582; 2. angew. Chem., 1931, 44,597; A., 1931, 99956 GENERAL AND PHYSICAL CHEMISTRY.of reactions which were found to occur a t every collision and areinertia-less :Na + X, --+ NaX + XNaX, + X+ NaX + NaNa + HgCl, + NaCl + HgClNa + HgCl + NaCl + Hg.More detailed examination of these reactions, however, and ofsimilar ones using other substances, has now shown that manyatomic processes involve a quite appreciable energy of activation.In particular, H.von Hartel and M. Polanyi 59 have found that thereactions between sodium and alkyl halides have heats of activationwhich increase uniformly from the iodide (about zero) to the fluoride.These experiments have been elaborately extended by H. von Hartel,N. Meer, and M. Polanyi,60 using different alkyl radicals.have studied the cases ofsodium vapour with cadmium halides and with zinc chloride.Herethe results are almost entirely similar to those originally obtainedwith the mercury halides, but the heats of activation are oftenappreciable.The inertia-less reactions of sodium vapour with the hydrogenhalides have been studied by G. &hay6, and H. von Hartel.63The calculation of heats of activation by methods arising fromthe results of molecular spectra and the new theories of valencyhave been reported elsewhere (Hinshelwood, this vol., p. 18). It issufficient to say that the calculat'ions lead to values which are ofthe same order as those observed.A series of measurements on the total infra-red radiation emittedby the carbon monoxide-oxygen and hydrogen-oxygen flames underdifferent conditions has been made by W.E. Garner and his colla-borator~.~* I n the case of hydrogen and oxygen the maximumradiation is observed with the mixture H, + 0,, and not with thestoicheiometric mixture 2H, + 0, ; from which the authors concludethat hydroxyl radicals are probably responsible for the emission.An examination of the effect of catalysts on the speed of the flameE. Horn, M. Polanyi, and H. Sattler69 2. physikal. Chem., 1930, [B], 11, 97; A., 1930, 174.6o Ibid., 1932, [ B ] , 19, 139.62 Ibid., 1931, [B], 11,291 ; A., 1931, 282. 63 Ibid., p. 316; A . , 1931, 282.64 With F. Roffey, Nature, 1928, 121, 56; A., 1928, 105; J., 1929, 1123;A., 1929, 973; with C. H. Johnson, J., 1928, 280; A., 1928, 375; with K.Tawada, Nature, 1928, 122, 879; A., 1929, 21; with D.A. Hall, J., 1930,2037 ; A., 1930, 1379 ; with D. A. Hall and F. E. Harvey, J., 1931, 641 ; A.,1931,576; with K. Tawada, Trans. Faraduy SOC., 1930,26,36; A., 1930,263;with C. E. H. Bawn, J., 1932, 129; A., 234; cf. also E. K. Rideal, Ann.Reports, 1928, 25, 343.Also this vol., p. 43.Ibid., 1932, [B], 17, 220; A., 680THOMPSON : FLAMES AND MECHANISM OF CHEMICAL CHANGE. 57of carbon monoxide-oxygen mixtures, on tAe infra-red emission,and on the ionisation, reveals the existence of a ‘‘ residual ” radi-ation in addition t o that given out in the explosion itself. Garnerand Johnson suggest that this residual radiation arises from therecombination of ions. The important result with carbon monoxideflames, however, is the existence of a “ step ” in the curve showingtotal radiation emitted against percentage of hydrogen added.Addition of hydrogen diminishes the radiation observed untilo.0470 is reached; at this point a break is observed, and withincreasing proportion of hydrogen the radiation again diminishes,continuously, but more slowly.It should be added that, whilstdiminishing the radiation produced, addition of hydrogen increasesthe flame speed. Garner and Roffey conclude that, in accordancewith the earlier ideas of Bone, there are two chemical mechanismsoperative in the reaction, one occurring below the step, the otherabove it. From further experiments it is concluded that excitedcarbon dioxide molecules are the origin of the radiation.Further experiments deal with the effect of vessel size, additionof inert gases, and other factors on the position and magnitude ofthe ‘‘ step.” The relationship pHn p(COfOa) = E , originally thought toapply a t this point, is later amended to pHa pco2 = k.The “ step ”is unaffected by changes in the vessel dimensions.Bawn and Garner have recently stated that carbon dioxide andsulphur dioxide effect an increase of the pressure at the ‘‘ step.”The visible and ultra-violet spectra emitted by flames were firstexamined many years ago by Kirchhoff and Bunsen. Subsequentlythe work was continued by Liveing, Dewar, Hartley, and others.65It nearly always led to the discovery of flame continua-continuousspectra, having no line or band structure.66 The origin of suchcontinua is still a matter of doubt ; it seems probable that they ariseas a result of processes of recombination of free radicals present inthe flame, although alternative hypotheses are possible. In manycases, however, it is now found that superimposed upon the continuaare lines or bands caused respectively by the excitation of atomsand of molecules.All authors are agreed upon the fact that this excitation has itsorigin in the energy liberated in the elmentary transformations.The implications of this are twofold : first, it compels us to find inthe reaction scheme some elementary process the heat evolution ofwhich will produce the excitation observed ; secondly, it enablesus t o infer the presence or absence of certain intermediate productsin the reactions occurring.65 Cf.Eder and Valenta, “ Atlas typischer Spektren,” 1911.8 6 Summary by W. Finkelnburg, Physikal. Z., 1930, 31, 158 GENERAL AND PHYSICAL CHEMISTRY.H. F. Bonhoeffer and F. Haber 67 identified the bands emitted bya hydrogen-oxygen flame with those due to hydroxyl radical, andfor this and other reasons suggested that hydroxyl occurs as anintermediate product in the reaction chain. The significance ofthis has been discussed elsewhere.68 It suggested the chainH, + 0, = 20H,H + 0, + H, = OH + H,O,OH + H, = H,O + H,which has been so much discussed in recent years.69V. Kondratbev 70 has re-examined the spectrum of the flame ofburning carbon monoxide. This has been studied by W. A. Boneand his collaborators for many years.71 Kondrateev's measurementsare confined t o the ultra-violet region, since in the visible, increaseddispersion still leaves the spectrum too complicated for analysis.In the ultra-violet the bands are arrangedin series having a frequencydifference of approximately 600 cm.-l; the corresponding infra-red and Raman frequency is 672 crn.-l.A variety of considerationslead to the conclusion that excited carbon dioxide molecules are theemitters of the bands. The evidence is, however, to some extentnegative in that the bands observed cannot be assigned to any othermolecule which might be present in the flame. The change infrequency difference in the two cases could be explained by theexcitation of higher vibration levels in the flame.Kondrateev also observed the flame of sulphur burning in oxygen,the spectrum consisting of two groups of bands-one in the visible,the other in the ultra-violet-separated by a continuous region.These can be attributed t o the S, molecule and to SO respectively.The phosphorescent flames of carbon disulphide and of etherwere also studied; in the latter case formaldehyde bands areprominent.The spectrum of the flame of carbon disulphide has been measuredby A.Fowler and W. M. Vaidya.', It is found that the mostcharacteristic bands of the ordinary flame, extending from theblue to the near ultra-violet, form part of the system already knownto be due t o S, molecules. The ultra-violet bands of S, appear in67 2. physikal. Chem., 1928, 137, [ A ] , 263; A., 1929, 11; cf.also Ann.Reports, 1928, 25, 342 ; 1930, 27, 46.W. L. Garstang and C. N. Hinshelwood, Proc. Roy. Xoc., 1931,134, [A],1 ; A., 25.*6g W. Frankenburger, Trans. Faraday Xoc., 1931, 27,431 ; A., 1931, 1136.' 0 2. Physik, 1930, 63, 322; A., 1930, 1332.'1 W. A. Bone and D. T. A. Townend, '' Flame and Combustion in Gases,"Longmans, 1927.Proc. Roy. Soc., 1931,132, [ A ] , 310; A., 1931, 996BOWEN: THE STRUCTURE OF SIMPLE MOLECULES, ETC. 59absorption but can be obtained in emission if a stream of oxygenis directed on t o the flame. Emission bands of SO are seen, and ifthe flame is enclosed in a chimney, absorption bands of SO, can alsobe obtained.Generally similar results were obtained in experiments on theflames of sulphur and hydrogen sulphide, the latter showing bandsof hydroxyl.The spectrum of the phosphorescent flame of carbondisulphide 73 was re-examined, and bands due to SO and CS found.Fowler and Vaidya discuss the significance of their results from thepoint of view of the mechanism of combustion. It is possible toreconcile all the spectroscopic data with the theory of peroxidationand with the results of kinetic measurements made on the reaction.The spectrum of the hydrogen-nitrous oxide flame has beenstudied by A. Fowler and J. S. Badami.74 These authors summarisethe relevant facts concerning the most, common “reference ” spectra-“ water vapour ” bands (OH), “ ammonia ’’ bands, “ third positivenitrogen” bands (NO). The results show that this flame is similarto that of ammonia burning in oxygen, each showing bands due t othe molecules NH, OH, NO, and the so-called #-bands of ammoniawhich may be ascribed to the NH, molecule.V.Kondrateev 75 has summarised the data at present available uponthis subject. The following extract from his paper serves to indicatethe types of result obtained :Flame. Molecule. Flame. Molecule.H2+02 OH NH, + 0 2 NH, NH,( ?), OH, NOCO + 0, co, CH, + 0, CHcs, + 0, so, s, a ~ $ ~ ~ d e ” ) + 0, C,, CH, OH, CO,, CH,O(CN), 3- 0, CN, c2, co H2 + N,O NH, NH,(?), OHs + 0, so,s, C2H2 + 0 2 CH, c,p4 + 0, PO(?)HCN+ 0, CN,C, CO + N20 co2H. W. T.8. THE STRUCTURE OF SIMPLE MOLECULES FROM SPECTROSCOPIC,X-RAY AND ELECTRON DIFFRACTION DATA.A number of improvements in the technique of obtaining molecularspectra have been recorded, and will be found in the work referredto below; in addition may be noticed improvements in gratingspectrographs 76 and far infra-red spectrographs.77 The question73 H.J. Emelbus, J., 1926, 2948.74 Proc. Roy. SOC., 1931, 133, [A], 326.7 5 Proceedings of Congress on Chemical Kinetics, Leningrad, Sept. 1930.7 6 A. L. Loomis and G. B. Kistiakowsky, Rev. Sci. Instr., 1932, [ii], 3, 201 ;7 7 H. M. Randall, ibid., p. 196; A., 592; R. B. Barnes, Physical Rev., 1932,A., 592.[ii], 39, 562 ; A., 44460 GENERAL AND PHYSTCATA CHEMISTRY.of the polarisation of Raman scattering from the point of view ofthe " spinning photon " has received attention.78 Accurate experi-mental results are difficult to obtain, and some confusion has beencaused by lack of satisfactory data.An outline of the methods by which the structure of a simplemolecule can be deduced has already been given.79 From X-ray orelectron-diffraction methods intramolecular distances are obtained.80The fine-structure, i e ., the rotational constituent, of absorptionbands in the infra-red, visible, or ultra-violet region, or of Ramanbands B1 provides values of the moments of inertia of the molecule,whence the interatomic distances and angles can be calculated.The vibrational frequencies of the molecule, also obtained fromabsorption band or Raman data, through a treatment of themolecule as a system of masses and springs, allow of calculations ofthe angular dispositions of the masses and of the force constants ofthe links.82 The spectroscopic methods naturally depend for theirreliability on the accuracy of the interpretation of the experimentaldata, that is, on the correct allocation of observed frequencies toparticular transitions.This would not be so difficult if everyimportant vibrational band were completely resolved into itsrotational constituents and selection rules applied.83 Owing, how-ever, to the elaborate technique necessary to overcome the experi-mental difficulties, there is a t present a lack of adequate data formost simple molecules, so that the selection of moments of inertia,and still more, of fundamental vibrational frequencies, often becomesa debatable rather than an answerable problem.Further diffi-culties arise in the question of the distribution of forces within themolecule, i . e . , whether the forces are associated only with chemical(Sir) C. V. Raman and S. Bhagavantam, Indian J . Physics, 1931 6,353 ;A., 107 ; Nature, 1932, 129, 22 ; S. Bhagavantam, Indian J . Physics, 1932, 7,79; A., 793; Nature, 1932, 129, 167; R. Bar, ibid., p. 505; A., 445; S.Bhagavantam and S. Venkateswaran, ibid., p. 580; -4., 445; S. Venkates-waran, Phil. Mag., 1932, [vii], 14,258; A., 898; J. Cabannes and A. Rousset,Cornpt. rend., 1932, 194, 79, 706; A , , 212, 320.Note: in theformu1,lc onp. 371 the unitsarenot accurately defined, and reference should be made to K. VC'. F. Kohlrausch," Der Smekal-Raman Effekt," Springer, Berlin, 1931.H.Gajewski, Physikal. Z . , 1932, 33, 122; A., 316; R. W. James, ibid.,p. 737; W. van der Grinten, ibid., p. 769.For rotational structure of Raman bands, see K. M'. F. Kohlrausch, op.cit., p. 5 0 ; A. Langseth, 2. Physik, 1931, 72,350; A. Carrelli and J. J. Went,ibid., 1932, 76, 236; A., 792.82 See R. Mecke, Z . physikal. Chenz., 1932, [B], 16, 409, 421; 17, 1; A.,559, 675.83 G. Placzek, 2. Physilc, 1931, 70, 84; A . , 1031, 893; D. M. Dennison,Rev. Mod. Physics, 1931, 3, 289; H. A. Kraus and G. P. Ittmann, 2. Physil:,1930, 60, 663.i9 Ann. Reports, 1931,28, 367BOWEN: THE STRUCTURE OF SIMPLE MOLECULES, ETC. 61linkages, and whether repulsions between non-linked atoms occur.84It is towards the solution of these difficulties that most of the workon the structure of simple molecules is a t present directed.As an illustration of the methods employed in correlating infra-red absorption-band data with Raman frequencies in order toobtain the energy levels of the molecule, reference may be made toA.Langseth and J. R. N i e l ~ e n , ~ ~ to P. E. Martin and E. F. Barker,86and to D. M. Denni~on,~' who examine the case of the molecule ofcarbon dioxide.88 This molecule definitely has a linear symmetricalstructure.89 The molecule of nitrous oxide is more complicatedand, though linear, has the unsymmetrical structure NN0.90 Thisstructure is also supported by other evidence of a very variedchara~ter,~l though it is not at present easy to reconcile this resultwith the very small dipole moment of the molecule.92The structure of the H,O molecule in the light of refined nearinfra-red absorption band measurements has been discussed byP.Lueg and K. Hedfeld,93 who conclude (from the calculatedmoments of inertia) that the molecule is an isosceles triangle of thefollowing dimensions : 0-H = 0.98 A.; H-H = 1.6 8.; angleHOH = 109". In this paper full references to earlier work will befound. Other new data for this molecule are presented by E. K.Pl~ler,~* I;. R. Weber and H. M. Randall,95 S. Rafalow~ki,~~H. Hul~bei,~' and H. Gajew~ki.~8Hydrogen sulphide appears to be a rectangular isosceles trianglewith S-H = 1.43 A. and H-H = 2-02 g.99 A. Dadieu andK. W. F. KohlrauschS9 from a general survey conclude that the0x0 angle in sulphur dioxide is 120".C. R. Bailey and A. B. D.84 H. C. Urey and C. A. Bradley, PhysicaZ Rev., 1931, [ii], 38,1969 ; A., 107.8 5 2. physikal. Chem., 1932, [B], 19, 35.8 6 Physical Rev., 1932, [ii], 41, 291.8 7 Ibid., p. 304; A., 982.8 8 See also A. B. D. Cassie and C. R. Bailey, 2. Physik, 1932, 79, 35.89 For X-ray results, see H. Gajewski, Zoc. cit. (ref. 80).E. K. Plyler and E. F. Barker, Physical Rev., 1931, [ii], 38, 1827; A.,1031, 108; A. Langseth and J. R. Nielsen, Nature, 1932, 130, 92; A., 897.91 K. Clusius, Nature, 1932,130,775; G. Herzberg, 2. physikal. Chem., 1933,[B], 17,68; A., 680; C. R. Bailey, Nature, 1932,130, 239; A., 997.s2 H. v. Braunmuhl, Physikal. Z., 1927,538, 141; J. W. Williams and C. H.Schwingel, Physical Rev., 1930, [ii], 35, 855; P.C. Mahanti, Physikal. Z.,1931,52,108; A., 1931, 287.93 2. Physik, 1932, 75, 512; A., 558.04 Physical Rev., 1932, [ii], 39, 77; A., 212.9 5 Ibid., 40, 835; A., 792 (far infra-red).9 6 Bull. Acad. Polonaise, 1931, [ A ] , 623; A., 792.O 7 Compt. rend., 1932, 194, 1474; A., 559 (Raman spectra).g8 LOG. cit. (ref. 80).90 A. Dadieu and K. W. F. Kohlrctusch, Physikal. Z., 1932,33,165; A., 32062 GENERAL AND PHYSICAL CHEMISTRY.Cassie from infra-red data show that there is a close similarity ofstructure between sulphur dioxide and chlorine dioxide. Theunpaired electron of the latter therefore takes no part in the linkagesof the molecule. According t o the assumptions made as to thedistribution of forces within the molecule, they show that twostructures can be deduced, the angles OSO and OClO being 60" for" central forces " and 122" and 140" respectively for " valenceforces." On evidence based on the as yet incompletely resolvedrotational structure they prefer the smaller angle, as the largerappears t o give too great interatomic distances.2 The chemist,however, would select the larger-angled solutions as having valencyforces and agreeing with the selection rules, and would regard thequestion of the linear dimensions of the molecules as still unsettled.Chlorine monoxide is probably a rectangular isosceles triar~gle.~The ozone molecule is reported on Raman spectra evidence to betriangular but not equilateral; its structure may possibly beanalogous t o that of sulphur dioxide.The vibrational structure of the near infra-red absorption bandsand of the Raman bands of ammonia has been carefully investi-gated, but entire agreement has not yet been reached as to themoments of inertia of the molecule. One of them is difficult t oobtain from spectroscopic data, but can be calculated by an applic-ation of wave-mechanics.' The original pyramidal form has beencodrmed, but the table below shows the structures deduced bydifferent treatments of the experimental data :Distances Dennison Langseth.&)and Luegand and (Dissolvedangles.Hedf'eld. Uhlenbeck. (Gaseous.) in water.)N-H 1.04 1.02 0.89 0.90H-H 1.72 1.64 0.92 0.93Height ofpyramid 0.3 0-7 1 0.73Angle HNH 110" 107" 62" 62"The HNH angle of about 110" is probably the most reliable;Langseth's results depend on the choice of a very small value for1 Nature, 1932,129,652 ; A., 888; Proc.Roy. SOC., 1932, [ A ] , 137,622 ; A.,1075.a Cf. R. Wierl, Physikal. Z., 1930, 31, 1028; A., 1931, 13.3 C. R. Bailey and A. B. D. Cassie, Zoc. cit. (ref. 1).4 G. B. B. Sutherland and S. L. Gerhard, Nature, 1932, 130, 241 ; A., 983.5 P. Lueg and K. Hedfeld, 2. Physik, 1932, 75,599; A., 674.6 A. Langseth, ibid., 77,60 ; A., 897 ; E. Amaldi and G. Placzek, Naturwisa.7 D. M. Dannison and G. E. Uhlenbeck, Physical Rev., 1932, [ii], 41, 313;8 R. RI. Badger and R. Mecke, 2. physikal. Chem., 1929, [B], 5, 333; A . ,1932, 20, 521 ; A., 897.A., 982; N. Rosen and P. M. Mor~e, ibid., 42,210.1929, 1363BOWEN : THE STRUCTURE OF SIMPLE MOLECULES, ETC.63one of the moments of inertia, but independently of the probableinaccuracy of this choice they serve to show how little the ammoniamolecule is deformed by dissolution in water.Pentatomic tetrahedral molecules have been examined by anumber of workers. J. G. Moorhead9 has calculated moments ofinertia of the methane molecule, and a discussion of the fundamentalfrequencies of the molecule is given by S. Bhagavantam.lo C. Schaeferand R. Kernll present accurate measurements of the infra-redabsorption bands of carbon tetrachloride and attempt to allocatethe bands to particular transitions in terms of the four fundamentalfrequencies.12 H. C. Urey and C. A. Bradleyl3 show that thefour fundamental frequencies of the tetrahedral molecules CCI,,SiCI,, SnCI,, CBr,, SnBr,, and TiCI, cannot be related to oneanother on the simple assumption of valency forces; an allowancemust be made in addition for the mutual repulsion of the corneratoms.New infra-red absorption bands of formaldehyde vapour havebeen measured,14 and G.Herzberg and K. Franz l5 find that themolecule gives a fluorescence spectrum with two characteristicfrequency differences identical with the Raman lines. Fromthe rotational structure of the ultra-violet absorption spectrum,G. H. Dieke and G. B. Kistiakowsky16 deduce the distances:C-0 = 1.19 B.; H-H = 1.88 A , ; C-H = 1.15 A.; angleHCH = 110".The identification of the vibrations of the acetylene molecule areat present uncertain; l7 provisional moments of inertia for theethylene molecule have been arrived at by R.M. Badger andJ. L. Binder.18It is remarkable that the angles obtained between the valenciesof the hydrogen atoms in the molecules H,O, H3N, (H,C), andH,CO are all close to the tetrahedral angle 109" 28'; H,S at presentappears to be an exception with an angle of 90". E. J. B.Physical Rev., 1932, [ii], 39, 83; A., 212.lo Nature, 1932, 129, 830; A., 675.l1 2. Physik, 1932,78, 609.la Cf. A. Langseth, ibid., 1931,72,350; A., 1931, 1363.l3 Physical Rev., 1931, [ii], 38, 1969; A., 107.l4 J. R. Patty and H. H. Nielsen, Physical Rev., 1932, [ii], 39, 957; A,,558; R. Titeica, Compt. rend., 1932, 195, 307; A., 897.2. Physik, 1932, 76, 710; A., 896.l8 Proc.Nat. A d . Sci., 1932, 18, 367.17 A. R. Olson and H. A. Kramers, J . A m r . Chem. SOC., 1932,54, 136; A.,320; W. Lochte-Holtgreven and E. Eastwood, Nature, 1932, 130, 403; A.,1075.l8 P h y s k l Rev., 1931, [ i i ] , 38, 1442; A., 6 ; see also H. H. Nielsen, ibid.,p. 1432; A., 664 GENERAL AND PHYSICAL CHEMISTRY.9. GENERAL STEREOCHEMISTRY.During this year the greater part of the new and comprehensivetextbook of Stereochemistry edited by K. Freudenberg l9 hasappeared. The earlier parts contain very thorough discussions ofthe physical aspects of the subject, by Mark, V. M. Goldschmidt,Mecke, Dadieu, and others, including a discussion of the newphysical theory of optical activity by Werner Ktthn. The moreorganic side is discussed in the later parts, by Freudenberg, Ebel,Richard Kuhn, Meisenheimer, and others.This book bringstogether for the first time the various physical and chemicalinvestigations bearing on the subject.W. H. Mills has published two important papers dealing withgeneral aspects of stereochemistry. In the first 2O he discusses theenergy relations of the cyclic compounds and the conditions oftheir formation. In the second21 he deals especially with themechanism of the racemisation of tercovalent atoms, and of thetransmigration in the Beckmann reaction ; he also gives the clearestand most thorough discussion which has yet appeared of the originof optically active compounds in living matter, and shows howthe growth of an organism must necessarily accentuate anydisproportion between the antimeric forms.Now that the normal arrangements of the valencies of multivalentatoms have been ascertained, we are in a position t o consider whatmodifications the molecule can undergo, how far it resists thesemodifications, and what are the forces that tend to bring themabout.The’ modifications are of three kinds :(I) Rotation of atoms with their attached groups about the lineof a single link : “ free rotation.”(11) Bending of the valencies, i.e., expansion or contraction oftheir angles.(111) Stretching or compression of the links : increase or diminu-tion of the distances between the linked atoms.The restoring forces exerted by the valency bonds themselvesagainst these deformations are for (I) zero, since no change of angleor distance is involved.lo ‘( Stereochemie : eine Zusammenfassung der Ergebnisse, Grundlagenund Probleme,” Leipzig, Deuticke, 1932; 5 of the 8 parts have now beenpublished, price RM.18 each.2 o Stkrkochimie des compos6s cycliques : Report of the Fourth ChemicalSolvay Conference, Paris, Gauthier-Villars, 1931, pp. 1-51.a1 Presidential Address to the Chemical Section of the British Association :in “ The Advancement of Science,” 1932, pp. 37-56. B. A. Report, 1932,p. 37SIDGWICK : GENERAL STEREOCHEMISTRY. 65For (11) they are given by the force constants derived from theabsorption or Raman spectra. These are much less easy to deter-mine for the bending than for the stretching, and are only knownin a few simple instances. For the C-H link the Raman spectraindicate 22 that a change ,of angle of 10" (about 0.1 B.U.) requiresabout 700 cals.per g.-mol. : for the linear molecule of hydrogencyanide and acetylene the spectrum givesZ3 similar values of 788and 772 cals. respectively. We may assume that this resistance ismuch the same for other atoms attached to carbon. As will beshown later, there is reason to think that for the valencies of oxygenand sulphur, and perhaps of all atoms with a covalency of lessthan four, it is very much smaller.(111) The resistance to stretching is much greater, and is givenby the force constants, which are known for a large number oflinks.24 The energy required for an increase of distance of 0.1 B.U.is on the average 3000 cals.for a single link; for G-C1 it is 2200cals.23The agencies external to the valencies which tend to deform themolecules are :1. The thermal impacts of other molecules : energy = IcT, or600 cals. per g.-mol. at 25".2. The dipole attractions and repulsions; 25 for two dipoles ofmoment 1 x e.s.u. at a distance of 3 A.U., the dipole potential-the work of complete separation of the dipoles-is about equal tothe thermal energy at 25".3. The van der Waals attraction between the atoms.26 Theimportance of this factor has only recently been recognised;and isstill somewhat doubtful. It seems, however, to be effective inethylene dichloride, accorqng to the recent observations of Kohl-rausch. The scattering of X-rays by the vapour of ethylenedichloride showed2' that the majority of the molecules had thechlorine atoms as far removed as possible (" trans-position "), butthe shape of the curves indicated that not all the molecules were inthis state.It was concluded that the trans- was the favouredposition, owing to the dipole repulsion, but that the thermalagitation, which for this molecule should be of the same order ofmagnitude as the dipole potential, disturbed the molecules from it22 See Ann. Reports, 1931, 28, 371, 401.23 H. A. Stuart, Physikal. Z., 1931, 32, 793 ; A., 1931, 1356.24 Ann. Reports, 1931, 28, 401.26 For a detailed discussion, based on wave mechanics, of this and the otherintermolecular and interatomic forces, see H. Eyring, J. Amer. Chm. SOC.,1932,54,3191; A., 996.27 P.Debye, Physikal. Z., 1930,31,142,419; A., 1930,400,843 : observeddistance, 4.4 & 0.1 k U . : calculated for trans-form, 4-25.25 Ibid., p. 390.REP.-VOL. XXIX. Cis GENERAL AND PHYSICAL CHEMISTRY.to some extent. This was confirmed by the measurement of thedipole moment, which was found to be considerable, though lessthan that required for t#he cis-form (the tyans- has no moment), andto increase with rise of temperature owing to the greater freedom ofrotation; 2* it was also found that in solution, where the dielectricconstant of the medium is larger, and hence the dipole potentialsmaller, the moment is larger than it is in the gas. It has now,however, been shown 29 that in the Raman spectrum of ethylenedichloride the line corresponding to the oscillations of the C-Cllink is double, one component being stronger than the other, andthe ratio of the intensities approaching unity as the temperaturerises. In cis- and trans-dibromoethylenc, which are distinct sub-stances, the C-Br Raman lines are not quite in the same position,indicating that the constant for the C-Br link is somewhat differentaccording as the second C-Br link is in the cis- or tr~ns-position.~~Kohlrausch concludes from this that ethylenc dichloride consists,nbt of molecules in or near the trans-position, but of a definitemixture of the cis- and the trans-form, with the latter predominating ;otherwise we should find one blurred line instead of two sharp ones.If so, there must be some force to hold the molecule for a time inthe cis-position, against the dipole repulsion, and this can only bethe van der Waals attraction of the chlorine atoms, which in thecis-position are about 2.7 A.U. apart, much like neighbouringmolecules of liquid or solid chlorine.The work required to separatethem against this force can be roughly estimated from the heat ofevaporation of chlorine. This is, a t the ordinary temperature, about4 kg.-cals. per g.-mol., or 2 kg.-cals. per g.-atom. If we supposethat in the evaporation of the liquid each chlorine atom has toovercome the van der Waals attraction of 4 or 5 neighbours, thiswould make the heat of separation of two atoms 400-500 cals.,which is of the same order as the dipole potential. The sameinfluence seems to be active in dichloroethylene, CHCKCHCL. Herethe cis- and the transform (b.p. 60.1" and 47.5") are stable at theordinary temperature, but change into one another at measurablcrates in the vapour a t 300"; and it has been found 31 that theequilibrium mixture, from whichever side it is approached, contains28 C, P. Smyth, R. W. Domte, and E. B. Wilson, J . arner. Chem. SOC.,1931, 53, 2005, 4242; A,, 1931, 786; 1932, 110; C. T. Zahn, Physical Rev.,1931, [ii], 38, 521; A., 1931, 1113.29 I<. W. F. Kohlrausch, 2. physikal. Chew., 1932, [B], 18, 61; A., 897.30 A. Dadieu, A. Pongratz, and K. W. I?. Kohlrausch, Monatsh., 1932, 60,31 L. Ebert and R. Bull, 2. p ? / y s i / a l . L'hem., 1931, [ A ] , 152, 451 ; A., 1931,For a discussion, sco H. A.Stuart, I'hysikal. Z., 1831,32, 793; A., 1932,221 ; A., 898.430.1356SIDGWICK : GENERAL STEREOCHXMISTRY. 67about 63% cis and 37% trans. Since the dipole repulsion mustcertainly favour the trans-configuration, we can only conclude thatthe van der Waals force is more effective in the opposite direction.4. Electron repulsion of non-linked atoms. The “ atomicradii” calculated from the distances between the nuclei of linkedatoms are now known to within a few hundredths of an A.U. Butthe least distance between two atoms which: are not linked is muchgreater than corresponds to these radii; and this fact, which is ofgreat importance in stereochemical phenomena, has been somewhatoverlooked. For example, the “radius” of a krypton atom canbe determined (1) from its spectrum, giving a value correspondingto the radius in a (2) from theviscosity of the gas,32 the “ collision radius ”; (3) from thecrystalline solid.The values are : spectroscopic 1.06, collisionradius 1.55, crystal radius 2.01 B.U. This shows that the distanceof nearest approach is in the crystal about 2 A.U. and in the gasabout 1 B.U. greater than in the link. For this greater distance inthe crystal there is much evidence. The densities of the diatomic“ permanent ” gases in the solid state, compared with those deducedfrom their internal radii, show that to fill up the space in the crystalwe must put an “ envelope ” about 1 A.U. thick round each mole-cule. In solid benzene hexachloride the minimum distance betweenthe nuclei of two chlorines belonging to different molecules is3-74 A.U.= This gives an external radius of 1-87, and if we subtractthe internal radius of 0.97 A.U., we are left with an envelope 0-90A.U.thick. So, too, Hendricks 34 has shown that in a whole seriesof solid organic compounds the nearest approach of two carbonatoms of different molecules is from 3.6 to 3.9 B.U. In graphitethe distance between the separate flat sheets, each of which is reallya giant molecule, is 3.41 A.U. These distances are due essentiallyto the electrostatic repulsion of the electrons, whose magneticmoments are already paired within the molecule. This force willgradually increase as the atoms approach one another, until itbalances the van der Waals attraction, which is due to polarisationand resonance.The chemist is more interested in molecules in the liquid or gaseousthan in the solid state, and here owing to their greater freedom ofmotion they will come nearer, and the “ envelopes ” will be thinner,its the collision radii show.The data for liquids and vapours are less32 For a very ingenious method of deducing the structure from the collisionarea, see R. M. Melaven and E. Mack, J . Amer. Chern. SOC., 1932, 54, 888;E. H. Sperry and E. Mack, ibid., p. 904; E. Mack, ibid., p. 2141 ; A., 563,566,904.link, the “ internal ” radius;33 S. B. Hendricks and C. Bilicke, ibid., 1926, 48, 3007; A., 1927, 98.94 Chern. Reviews, 1930, No. 468 GENERAL AND PHYSICAL CHEMISTRY.direct than for solids, and the distances will obviously vary with theconditions, and especially with the thermal energy.Good evidence of this repulsion is given by the measurements,from the scattering of X-rays by the vapour,35 of the distancesbetween the chlorine atoms in carbon tetrachloride, chloroform,and methylene chloride, which present several points of interest.As successive chlorine atoms are replaced by hydrogen atoms, thisdistance steadily increases :CCl, : C1-C1, 2.99 & 0-03 A.U.CHCl, : ,, 3-11 & 0.05 A.U.CH,Cl, : ,, 3.23 -J= 0.1 A.U.In carbon tetrachloride thc absence of dipole moment and thcspectroscopic data indicate that the molecule is symmetrical andhence the valency angle is 109" 28' ; the C-C1 distance must thereforebe 1.83 & 0.02 A.U.The distance between carbon and chlorine inmethyl chloride is given 35 as 1.9 & 0.1 A.U., but for a molecule ofthis kind the calculation of the distance from the curves is peculiarlydifficult, and the result may be in error by as much as 0.2 or 0.3 B.U.The '' internal " radius of carbon is known from many sources tobe 0.77, and that of chlorine, as measured in the gas, and confirmedby many of its compounds, is 0-97, giving the C-C1 distance as1.74 A.U. This is compatible with the results obtained for methylchloride, but in carbon tetrachloride, where the measurements aremuch more accurate, the distance is found to be nearly 0.1 A.U.longer.Now, if in carbon tetrachloride the chlorine atoms arecrushed together against their mutual repulsion, this must lead toa stretching of the link between them, and the observed excess of0.09 A.U.in their distance may well be due to this cause. It canbe shown that an extension of this order is to be expected. Thepotential energy due to the whole distortion in the carbon tetra-chloride molecule, the crushing and the stretching (there is nobending) can be found from the observed heat of formation. Theheat of formation from its atoms of the C-C1 link is 74.7 kg.-cals. inmethyl chloride, and 77.6 kg.-cals. in ethyl chloride. We may takethe mean value 76.2 as the heat of formation of the unstrained GC1link. Hence that of the carbon tetrachloride molecule, if therewere no strain, would be 4 x 76.2 = 304.8 kg.-cals. The observedvalue is 2904 kg.-cals., and the difference, 14.4 kg.-cals., mustrepresent the potential energy of the strain in the molecule in all itsforms.From the force constant for GC1 quoted above we cancalculate that to stretch the GC1 link by 0.09 B.U. needs 1.8 kg.-cals., or for the four links 7.3 kg.-cals. This leavcs 14.4 - 7.235 I?. Debye, 2. E'lektrochem., 1930, 36, 612 ; A., 1930, 1350SIDGWICK : GENERAL STEREOCHEMISTRY. 69= 7.2 kg.-cals. for the potential energy of compression of the chlorineatoms. The data used in this calculation, especially the thermaldata, are only approximate, and errors of 2 or 3 kg.-cals. are quitepossible; but the results are sufficient to show that the energyrelations are of the right order.This question of the length of the link is important when we tryto calculate the valency angles in chloroform and methylenechloride.If we take the length of the GC1 link to be 1.83 A.U.,the Cl*C-Cl angle in methylene chloride is 124" r f 6" : if we take itto be 1-74 A.U. the angle is 136" 6". I n either case it appearsthat the mutual repulsion of the chlorine atoms is sufficient toseparate them, against the resistance which the valencies offer tobending, to a distance of 3.2 A.U., which involves an " envelope ''rather more than 0.6 A.U. thick. It is, of course, to this atomicrepulsion that the " Thorpe-Ingold " effect is due.Another problem connected with atomic repulsion is that of theoptical activity of ortho-substituted diphenyl derivative^.^^ Thesuggestion of Mills and Kenyon that this is due to a steric inter-ference of the ortho-groups, preventing the rotation of one nucleusround the common axis of the two, has been fully confirmed by thework of W.H. Mills and K. A. C. Elliott,37 who found the samephenomenon with a 1 : 8-naphthalene derivative; and recentlyMills and J. G. Breckenridge 38 have shown that it occurs also with8-substituted N-alkylquinolines. Various attempts 39 have beenmade to determine what are the smallest groups or atoms which inthe ortho-position can inhibit the rotation. It was found that withfour ortho-methyl groups (I) racemisation practically does notoccur; 40 and that with fluorine and NH, on each ring 41 (11) theracemisation, though easy, is not instantaneous : it needs about36 For earlier references, see Ann.Reports, 1926, 23, 119; 1931, 28, 394.37 J., 1928, 1291.39 See e.g., R. Adams and co-workers, J. Amer. Chem. Soc., 1929-32 : E. E.40 W. W. Moyer and R. Adams, J. Amr. Chem. Soc., 1929, 51, 630; A.,4 1 E. C. Kleiderer and R. Adams, ibid., 1931, 53, 1575; A., 1931, 720.38 J., 1932, 2209.Turner and co-workers, J., 1929-32.1929, 43770 GENERAL AND PHYSICAL CHEMISTRY.20 minutes in boiling ethyl alcohol. These last are the smallestgroups which have yet been found capable of preventing racemis-ation. A model of o-fluoro-0‘-aminodiphenyl is given in Fig. 3 ;the radii adopted are : C 0.77 (C-C in the ring 1-42), N 0.71, F 0.68,H 0-37. It will be seen that if the hydrogen atoms of the amino-group are turned out of the way, the “inner spheres” of thenitrogen and fluorine atoms do not touch.The geometry of theortho-positions in diphenyl is very simple; if R is the radius of theatoms attached to the 0- and 0’-carbons, the nuclei of these atomswill be 2-19 - R A.U. apart; hence their inner spheres will be2-19 - 3R apart, and will touch if R is greater than 2.19 + 3,or 0.73 A.U. The radii of fluorine and nitrogen are just below thislimit, and it is impossible to explain, if we take account only of theinner spheres, why these two atoms should restrict rotation. Butif we admit that the repulsion extends beyond this range, we cansee that it may be effective, as is shown in the diagram, where thedotted line represents an envelope 0.5 -4.U. thick. It will be observedthat the envelopes of the unsubstituted hydrogen atoms on theleft-hand side of the diagram are not more than about 0-1 A.U.apart.The question of the racemisation of the diphenyl derivatives isvery different from that presented by the chlorinated methanes, inthat it is dynamic and not static. It is impossible to detect theoptical activity of a compound if its time of half racemisation ismuch less than one minute. Hence an effective steric hindrance isone which requires more energy to overcome it than that of theheaviest blow which the molecule receives in a minute. A moleculeof‘ a diphenyl derivative in dilute solution at 25” will make about1013 collisions a second with the solvent, the average energy of thecollisions being 600 cals. per g.-mol. The number of collisions ofhigher energy than the mean can be calculated by Boltzmann’sequation, which shows, e.g., that there will be one collision of 30times the mean energy (18,000 cals.) about every ten seconds.Only some of these collisions will tend to turn the molecule roundand cause racemisation; we may perhaps assume that 10% willbe effective. In that event, if the work required to overcome theresistance of the envelope-the heat of activation-is 18,000 cals.,the molecule will on the average be racemised in 100 seconds, whichmeans that its activity will last just long enough to be detected.This conclusion is confirmed by the observation of Mills and Elliottthat their 1 : 8-naphthalene derivative, which racemised with ahalf life of 16 minutes in chloroform a t 15”, had a heat of activation,as determined from the temperature coefficient of the velocity ofracemisation, of 18,500 calsSTDGWICK : GENERAL STEREOCHEMISTRY. 71FIG. 372 GENERAL ANT) PHYSICAL CHEMISTRY.Another group of phenomena in which the atomic repulsionSeems to be concerned is the valency angles as measured by meansof the dipole moments.42 This work has led to the remarkableconclusion that while the angle for carbon is not much greaterthan the tetrahedral (110-lZO"), for oxygen and sulphur it is farlarger, and usually about 140"; although, according to the wave-mechanical conclusions of Pauling, the angle for oxygen and sulphurshould be nearer to 90". This can only be understood by consideringthe actual compounds employed. In order to avoid complicationsdue to the mutual induction of dipoles, it is desirable to have theseremoved in the molecule as far as possible from one another. Hencethe method usually adopted is to compare the moment of diphenyl-methane, or diphenyl ether or thioether, with those of its mono-and di-substitution products containing polar groups (CH,, Br,NO,) in the para-position. What we really learn, therefore, is theangle of the valencies attaching carbon, oxygen, or sulphur to twophenyl groups.It is easy to see from the model that if the two rings are to becapable of rotating independently of one another, and so of passingthrough a plane phase, the valency angle of the central carbon oroxygen must be rather larger than the tetrahedral angle (about118") even if we disregard the envelopes of the hydrogen atoms inthe ortho-positions; if we take these into account it will be about140". In the dipole measurements we are concerned with theaverage value of the valency angle, and not with the result ofexceptionally severe blows. There is of course no necessity for thetwo rings to have the plane structure as one of their normal phases,but it is obvious that the thermal agitation will tend to promotethis, and will increase the vnlency angle to some extent. Theextent will depend on the resistance of the angle to deformation,of which we know the value for carbon, but not for any other element.Taking the energy of bending of the carbon valencies as 750 cals. forlo", we can see that if the whole 600 cals. of energy of the thermalimpacts was devoted to increasing this angle (which of courseis impossible), it would cause an expansion of 9". The dipolemeasurements indicate that for carbon the expansion is not morethan 10" a t the outside, but for oxygen and sulphur i t is about 30"(if we accept Pauling's view that the normal angle for a bicovalent42 E. Bergmann and co-workers, 2. physikal. Chem., 1930, [B], 8, 111; A . ,1930, 979; [B], 10, 397; A., 1931, 23; 1932, [B], 17, 81, 92, 100, 107; A . ,677; Ber., 1932, 65, 446, 457; A., 506, 507; 2. Elektrochem., 1931, 37, 563;0. Hassel and E. Nsshagen, 2. physikal. Chem., 1932, [B], 15, 417; A., 322;K. L. Wolf, ibid., [B], 17, 465; A., 794; C. P. Smyth and W. S. Walls, J.Amer. Chem.. SOC., 1932, 54, 1854, 3230; A., 794, 984SIDGWICII. : GENERAL STEREOCHEMISTRY. '73atom is a right angle, it is 50"). This strongly suggests that theresistance to bending of the valencies of a bicovalent atom is farweaker than with an element in which all the 8 electrons of theoctet are shared; indeed, since the energy is proportional to thesquare of the deflexion, it suggests that the value for oxygen orsulphur is not more than a thirtieth of that for carbon-say 30 cab.for 10" instead of 750. The Raman data for compounds like watershould afford evidence on this point, but it does not seem that thishas yet been obtained.This conclusion seems to be supported by the heats of formationof multiple link~.~3 It has been found that the relative values ofthe heats of formation from their atoms of single, double, and triplelinks of carbon to carbon are as 1 : 1.8 : 2-3, which is an indicationof the strain in the multiple links; but that for the links of carbonto nitrogen, oxygen, or sulphur the values are almost exactly as1 : 2 : 3, which shows that with these elements the strain is muchless. N. v. s.E. J. BOWENC. N. H~NSHELWOODN. V. SIDQWICKH. W. THOMPSONJ. H. WOLFENDEN43 Ann. Reports, 1931, 28, 387.c

ISSN:0365-6217    

DOI:10.1039/AR9322900013

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

INORGANIC CHEMISTRY.IN reviewing the work on Inorganic Chemistry which has beenpublished during the past year it is perhaps allowable in the firstplace to take a somewhat wider view and to consider the main linesupon which investigations have run during the past few years.I. Discovery and Investigation of New Elements.This phase of chemistry has, of course, almost come to an end.Nevertheless, a great deal of work has been done on the compoundsof the element rhenium, which was only discovered as recently as1925.l Masurium,2 announced a t the same time as rhenium andillinium (At. No. 61), seems to have gone the same way as so manynew elements, but the search for these and for the missing alkalimetal (No. 87) and halogen (No, S 5 ) is being prosecuted with the aidof all the modern technique and appliance^.^ There is a tendencyto name these elements somewhat prematurely.It has been sug-gested that the highest possible at,omic number is 92.411. Investigation of Compounds of the Rarer Elements.Richer sources and improved methods of extraction of rarerelements, as well as the discovery of technical applications of manyof them, have been responsible for a greatly increased interest insuch elements as rubidium and c~esium,5 berylliumY6 gallium,' andgermanium .7III. Striking Developments with Old Elements.Applications of modern theories and refined physical methodshave shown that there is still much to discover about some of thebest known elements. The separation of ortho- and para-hydrogenmay be cited as a case in point,* and also the discovery of isotopesAnn.Reports, 1938, 25, 59; 1929, 26, 65; 1930, 27, 73; 1931, 28, 59;this vol., p. 88.Ibid., 1925, 22, 63.Ibid., 1929, 26, 43; 1931, 28, 49; F. Allison and E. J. Murphy, PhysicalRev., 1930, [ii], 35, 285; A., 1931, 1391; J . L. McGhee and M. Lawrenz, J .Amer. Chem. SOC., 1932, 54, 405; A., 355; F. Allison, E. R. Bishop, A. L.Sommer, and J. H. Christensen, ibid., p. 613 ; A., 317 ; F . Allison, E. R.Bishop, and A. L. Sommer, ibid., p. 616; A., 353.V. V. Narliker, Nature, 1932, 129, 402; A., 442.Ann. Reports, 1930, 27, 57. ' Ibid., 1929, 26, 51; 1930, 27, 63, 6s; 1931, 28, 55.Ibid., 1929, 28, 40.6 Ibid., 1929, 26, 44BASSETT. 75of hydr~gen,~ carbon,lo nitrogen,lo and oxygen,lo which until quiterecently had been regarded as simple elements.IV.Work: on the Older Elements and their Compou?zds.This, of course, includes the great majority of the inorganic workpublished and can be sub-divided as follows :-(i) Study of the valency stages. Numerous complex compounds ofbivalent silver have now been prepared.11 Several of the rare-earthmetals form well-defined bivalent compounds, notably samarium,europium, and ytterbium,12 which may be of great analyticalsignificance since the bivalent metals can be separated with greatreadiness from those which remain tervalent. The bromides ofter- and bi-valent zirconium have been prepared 13 and compoundsof univalent platinum and pa1ladi~m.l~(ii) Value of the co-ordination number and spatial character of theco-ordination and linkages.It is important to know, not only thevalencies of the elements in the old-fashioned sense, but also theco-ordination values, in Werner’s sense, with which they can act. Acertain amount of work now being done aims at determining theseva1~es.l~ The spatial arrangement of the co-ordinated atoms orgroups provokes investigations in connexion with the problem ofoptical activity associated with special elements. Optically active6-co-ordinated nickelous compounds were recently prepared.16 Itis, however, the problem of the 4-co-ordinated atom which arousesmost interest. Although the configuration is usually tetrahedral,it can apparently be coplanar in special circumstances. Telluriumand platinum compounds of the type PtX2Y2 have received muchattention in this connexion.17Three important theoretical papers have been published on thenature of chemical linkages.18 In the first paper several rules areformulated for electron-pair linkings, and the conditions specifiedunder which four strong linkings in one plane directed towards thecorners of a square become possible.In the second paper theconditions of stability of single- and triple-electron linkhgs aredefined. The conditions for single linking are found in the boronhydrides and for triple linking in nitric oxide, nitrous oxide, andThis vol., p. 77.l1 Ibid., 1931, 28, 51.l3 Ibid., 1931, 28, 55.Is Ibid., 1930, 27, 54; 1931, 28, 51; this vol., p. 78.l6 Ibicl., 1931, 28, 61.l7 I b d ., 1929,26,60,80; 1930,27,150, 164; 1931,28,62; this V O ~ . , p. 92.L. Pauling, J. Amer. Chern. SOC., 1931, 53, 1367, 3226; 54, 988; A . ,lo Ann. Reports, 1930, 27, 52.l2 Ibid., 1929, 26, 49; 1930, 27, 63.l4 Ibid., 1930, 27, 76.1931, 670, 1356; 1932, 56176 INORGANIC CHEMISTRY.oxygen. The third paper deals wiOh the transition from ionic toelectron-pair linkages.Much recent work l9 on the electrical conductivity, diffusivity,and reactivity a t high temperatures of a number of spinels, silicates,germanates, molybdates, and tungstates in the solid conditionappears to show that the structure of such compounds may be of twotypes. They may have an ionic lattice with conductivity of anionic nature and a relatively high diAusivity, or a double oxidelattice in which the conductivity is electronic and the diffusivitymuch lower.It would seem that some kind of equilibrium betweenthe two types of structure exists but that, at any rate in some cases,the double oxide type tends to become the more stable form a t highertemperatures. Thus, Mg,Ge04 has a transformation point at 1065".At lower temperatures it crystallises in a spinel type, and at highertemperatures it is isomorphous with olivine, Mg,Si04. The spineltype has a higher electrical conductivity which is a t least partlyionic, whilst the conductivity of the olivine type is electronic andassociated with, mainly, a double oxide lattice. In the case of doublehalides there is, similarly, a transition between complex salt anda'ggregate of simple halides.It is well known that salts, e.g., cobalt sulphate, which, from thepoint of view of low-temperature reactions, are best considered interms of Co" and SO," ions, behave a t high temperatures in afashion which is most conveniently interpreted on the old dualisticlines in terms of COO and SO,.The above results appear to havesome bearing on this matter.Manysuch compounds might be mentioned, but the oxides of fluorine andbromine are perhaps the most striking.20(iv) Phase-rule examination of various systems. An immenseamount of work is being done on these lines. Phase-rule methodsare frequently the only ones by which the existence or non-existenceof particular compounds can be decided with certainty. Much ofthis work relates to aqueous systems and has important bearings onmany industrial processes.Various non-aqueous systems have ofrecent years been examined in connexion with slag equilibria inmetallurgical processes. Much of metallurgy consists of the phase-rule examination of metal systems by special methods, among whichX-ray examination plays an increasingly important part. Referencesto practically all the systems examined in the last few years are given19 W. Jander, 2. angew. Chem., 1931, 44, 870; A., 1931, 1356; Z. anorg.Chem., 1930, 192, 286, 295; 1931, 190, 306; A., 1930, 1351; 1931, 1236;W. Jander and W. Stamrn, ibid., 1931, 199, 1G5; 1932, 207, 289; A., 1931,'399; 1932, 985.(iii) Isolation of previously unknown simple compounds.20 Ann.Reports, 1929, 26, 63; 1930, 27, 71BASSETT. 77in the Annual Reports. A great deal of Inorganic Chemistry stillrequires revision by phase-rule methods.(v) Mit3ceZZaneow.s. Most of the remaining work can be groupedunder the heads of new methods of preparation, preparation of newcompounds of well-known types, study of the course or mechanismof reactions, but none calls for special mention here with the exceptionof oxidation,which has been the cause of much work on the corrosionand " passivity " of metals.21Group 0.The formation of compounds of krypton with chlorine and brominehas been announced.22 It is clear that this requires confirmationand verification.Liquid helium continues to be used for obtaining temperatures inthe neighbourhood of the absolute zero.Carbides, nitrides, borides,and silicides of the heavier metals become superconductors a t verylow temperatures. 23 An interesting account and discussion ofsuperconductivity has been given by J. C. McLennan and hisco -workers. 24Group I .A hydrogen isotope of mass two appears to be well established 25and should be of great importance in the study of isotopes if thepreliminary account of the enrichment of the residues of electrolytichydrogen plants in this isotope should be confirmed by furtherwork.26 By the action of atomic hydrogen on oxygen a t low tem-peratures there is formed what is considered to be a new form ofhydrogen peroxide 27-possibly with the structure E>O:O. At- 115" it changes into the ordinary form with partial decomposition ;97% of the theoretical yield of hydrogen peroxide is said to beobtained when hydrazobenzene in alcoholic solutions is convertedinto azobenzene by the action of gaseous oxygen.2821 Ann. Reports, 1929, 26, 38; 1930, 27, 55.22 A.von Antropoff, K. Weil, and H. Frauenhof, Nuturwiss., 1932, 20, 6 8 8 ;23 W. Meissner, H. Franz, and H. West,erhoff, 2. Physik, 1932, 75, 521 ; A , ,24 Nature, 1932, 130, 879; A., 1193.25 H. Kallmann and W. Lasarev, Naturwiss., 1932,20, 472; A., 790; N. S .Grace, J . Amer. Chem. SOC., 1932,54, 2562; A., 790.26 E. W. Washburn and H. C. Urey, Proc. Nut. Acad. Sci., 1932, 18, 496;H. C. Urey, F. G. Brickwedde, and G. M. Murphy, PhysicaZ Rev., 1932, [ii],40, 1; A., 554:A., 1007.566.27 K.H. Geib and P. Harteck, Ber., 1932, 65, 1233, 1551; A., 1098.28 J. H. TVdton and G . W. Filson, J . Arner. Chern. Soc., 1932, 54, 3223;A., 109878 INORGANIC CHEMISTRY.The vapour pressures of normal hydrogen (the mixture of ortho-and para-hydrogen which is in equilibrium at room temperature)and of para-hydrogen have been measured up to 1 atm. The normalb. p.'s have been determined as - 252.754" and - 252.871"respe~tively.~~Apparatus has been described for preparing and handling alkali-metal hydrides without exposure to air. All members of the serieshave the sodium chloride str~cture.~" Excellent yields of lithiumaryls and of butyl-lithium are obtainable under essentially the sameconditions as those used for the related Grignard reagents .31Lithium chloride monohydrate forms solid solutions with2LiCI,CoC12,2H20 (= [Liz(H20),]"[CoC1,]").32 From this fact it isconcluded that the monohydrate is termolecular with the structure [.i H2° Li]" [ Li c13 1".The polymerisation is determined by theH2O H2Oneed for the lithium atom to become either 2- or 4-co-ordinated.The two lithium atoms in the complex kation are linked through theoxygen of the two water molecules.I n presence of moisture a 93% conversion of potassium chlorideto nitrate can be obtained by the action of nitrogen peroxidc.Nitrosyl chloride is formed a t the same time.33The polyhalogen compounds of the alkali metals continue to attractinterest. No anhydrous perbromide of potassium exists, but2KBr6,3H20 separates a t 0" from concentrated solutions.34CsBr, can be obtained however.34 KIBr2,H20 35 and KI,,3C6H26have been described ; also HI,,4C7H5N ; LiI,,4C7H5N ; KI,,2C7H5N.37Rubidium resembles cmium in being able to form a solid polyiodide,RbI,, whereas potassium cannot do so unless combined water,benzene, or other addenda are also pre~ent.~S RbFIC1, and CsFICl,have been prepared.3929 W.H. Keesom, A. Bijl, and (Miss) H. van der Horst, Proc. K. Akad.30 E. Zintl, A. Harder, and E. Husemann, 2. physikal. Chem., 1931, [B], 14,31 H. Gilman, E. A. Zoellner, and m7. M. Selby, J . Amer. Chem. SOC., 1932,32 H. Bassett and (Miss) I. Sanderson, J., 1932, 1855; A., 811.33 C. W. Whittaker, F. 0. Lundstrom, and A. R. Merz, Ind. Eng. Chem.,34 I. W. H. Harris, J., 1932, 1694, 2709; A., 822.35 G.H. Cheesman and J. H. Martin, ibid., p. 586; A., 350.313 H. W. Foote and W. M. Bradley, J. Physical Chem., 1932,36,673 ; A , , 48.37 J. H. Martin, J., 1932, 2640; A., 1205.38 T. R. Briggs and E. S. Patterson, ibid., p. 2621 ; A., 1216.39 H. S. Booth, C. F. Swinehart, and W. C. Morris, J . Amer. Chem. Soc.,Wetensch. Amsterdam, 1931, 34, 1223; A., 453.265; A., 1931, 1358.54, 1957; A., 728.1931, 23, 1410; B., 304.1932, 54, 2561 ; A., 823; J . Phpsical Chem., 1932, 36, 2779; A., 1219BASSETT. 79The dissociation pressures of silver oxide have been measuredbetween 173" and 192".40 The solution of oxygen in molten silverand the phenomenon of spitting on solidification are due to formationof ~ g ~ 0 . 4 1Group I I .Beryllium of such purity that it dissolves in ordinary reagents onlywith difficulty can be obtained by electrolysis of solutions of thechloride or nitrate in liquid ammonia.42 Many other metals can besuccessfully deposited from solutions in liquid ammonia.43The fluoberyllates as a class appear to be isomorphous with thecorresponding sulphates.Many of them have been prepared andexamined.44It is said that Mg(SH)OH, MgS,, and MgS, can be stabilised in theform of compounds with two molecules of hexamethylenetetramineand ten of water.45The calcium silicates and aluminates, owing to their importancein connexion with cement, continue to attract several workers.46Pure anhydrous zinc chloride can be conveniently prepared inquantity by the action of dry hydrogen chloride on pure zinc inanhydrous ether.47The true solubilities in mercury of the metals of atomic numbers22-29 and of molybdenum, tungsten, and uranium have beendetermined by am improved method.These are in all cases verysmall even though, as in the case of copper, it may be possible todisperse considerable amounts of metal in the mercury.48 A wholeseries of what may be called low-temperature alloys have beenprepared and investigated by a novel and interesting methodinvolving the use of solutions of metals in mercury.49 These alloysare prepared either by admixture of the separate amalgams or by40 A. F. Benton and L. C. Drake, J . Amer. Chem. Soc., 1932, 54, 2186; A.,41 J. H. Simons, J. Physical Chew., 1932, 36, 652; A., 457; N.P. Allen,42 H. S. Booth and G. G. Torrey, J. Physical Chem., 1931,35,3111; A., 129.43 H. S. Booth and M. Menahem, ibid., p. 3303; A., 129.44 N. N. Ray, 2. anorg. Chem., 1931, 201, 289; 1932, 205, 257; 206, 200;4s A. Tettamanzi, Gazzetta, 1932, 62, 597 ; A., 1098.4 6 H. Ehrenberg, 2. physikal. Chem., 1931, [B], 14, 421; A., 131; E. T.Carlson, Bur. Stand. J . Res., 1931, 7, 893; A., 131; S. Nagai, J . SOC. Chem.Ind. Japan, 1931, 34, 4 1 8 ~ ; 1932, 35, 1 8 2 ~ , 3 2 0 ~ , 3 8 0 ~ , 3 9 4 ~ ; A., 131, 707,1008, 1217 ; idem, 2. anorg. Chem., 1932,206, 177; 207, 313; A., 707, 1008.4 7 R. T. Hamilton and J. A. V. Butler, J., 1932, 2283; A., 1008.4* N. M. Irvin and A. S. Russell, ibid., p. 891; A., 457.49 A. S. Russell, P. V. F.Cazalet, and N. M. Irvin, ibid., pp. 841, 852; A.,456; A. S. Xussoll and H. A. 11. Lyons, ibid., p. 857; A., 456; A. S. Russell,T. R. Kennedy, J. Homitt, and H. A. 31. Lyons, ibid., p. 2340; A., 1082.810.Inst. Metals, Sept. 1932, Advance Copy; A., 1090.A . , 131, 582, 70680 INORGANIC CHEMISTRY.interaction of one amalgam with an aqueous solution of a salt of theother metal. The character of the compounds formed is deducedfrom their behaviour with acidified permanganate or other oxidisingagents.The compounds obtained are in many cases entirely different fromthose found in alloys prepared by the usual high-temperaturemethods and this was to be expected. The compounds found inordinary alloys were, however, also obtained. A very large numberof new intermetallic compounds have been found by the new method,some of which contain mercury.Many of the compounds do notobviously belong t30 any class known to metallurgists but all of themfollow the simple rule that their empirical formulz correspond tototal valency electrons equal to 6, 9, or 12 or some simple multipleof these numbers.Group I I I .Crystallised boron of metallic appearance and 99% purity isobtained by passing very condensed high-frequency sparks betweenelectrodes of molybdenum or tungsten in a mixture of hydrogen andboron trichloride v a p o ~ r . ~ ~ New methods have been described forpreparing B,H,, B,H,Br, and B5H9,51 and reasons given for assign-ing B,N,H, a str~icture-nTH<BH.NH>BH-recalling BH*NH that ofbenzene.52 The compounds BBr,,HCN and BBr,,AgCN have becriprepared.53A convenient method for preparing anhydrous aluminium bromidehas been given.54 Aluminium chloride forms a white compoundAlCl,,BHCN with hydrogen cyanide.55 Tensimetric and othermeasurements have been made on the numerous ammines of alumin-ium chloride, bromide, and iodide.56 The mono-ammines in all casesare unimolecular non-ionic compounds [AlX,,NH,].Alkali oralkaline-earth permutites become blue when treated with alkalisulphide or polysulphide solution in presence of air. In absence ofair, only the polysulphides cause formation of the blue compoundsince the sulphide adsorption complex or compound is colourless.If the blue polysulphide permutites are prepared a t temperatures50 L.Hackspill, A. Stieber, and R. Hocart, Compt. rend., 1931, 193, 776;51 H. I. Schlesinger and A. B. Burg, J . Amer. Chem. SOC., 1931, 53, 4321 ;52 A. Stock and R. Wierl, 2. anorg. Chem., 1931,203, 228; A., 215.53 E. Pohland, ibid., 201, 282; A., 132.54 R. P. Bell, J., 1932, 338; A., 239.5 5 L. E. Hinkel and R. T. Dunn, J., 1931,3343; A., 132.5 6 W. Iqlemm and E. Tanke, 2. anorg. Chem., 1931, 200, 343; A., 1931,A., 1931, 1377.A., 350.1380; W. Klemm, E, Clausen, and H. Jacobi, ibid., p. 367; A., 1931, 1380BASSETT. 81above about 200" they are much more stable and yield the sameX-ray diagram as ultramarine.57 Base exchange by zeolites(permutites) can be applied so as to afford almost quantitativeyields of salts by double decomposition even whefi the ordinaryreaction between the solutions is in~omplete.~~A dark brown sublimate of Ga,O is obtained by heating a mixtureof the metal and the trioxide in a stream of hydrogen at 500-700".GaO could not be prepared.59GsBr3,6NH, and GaI,,6NH3, stable a t room temperature inabsence of moisture, are formed by the action of liquid ammoniaon the halides.60 GaN, which sublimes without decomposition above800°, can be prepared by the action of ammonia on gallium a t 900-1000".61The alloys of lanthanum with Pb, Sn, T1, Mg, Cu, Ag, and Au havebeen studied and several compounds were found in each case.62La, Ce, Nd, and Pr form compounds with mercury of the typeM,Hg,.G3Conductivity measurements on solutions of the normal and acidsulphates, and determinations of the degree of hydrolysis of thenormal sulphates, have been utilised to determine the basicity ofa number of the rare-earth metals.64Measurements of the solubility products of the hydroxides undersuitable conditions have been used for the same purpose 65 and, onthe assumption that the solubility product is proportional to thebasicity, the relative values of the latter for the metals Y, La, Pr,Nd, Sm, Gd, and Dy are found to be 1 : 1300 : 80 : 47 : 8 : 3 4 : 0.5.It is difficult to believe that there is so much difference betwcculanthanum and praseodymium.A full account has been published of the preparation, properties,and reactions of ytterbium di- and tri-halides.Reduction ofanhydrous tri-chloride or -bromide by hydrogen is the best methodfor preparing the dihalides, but the di-iodide can be prepared bydissociation of the tri-iodide in a vacuum a t 600".The dichloride and dibromide on strong heating break up into5 7 E.Gruner and E. Hirsch, 2. anorg. Chem., 1932, 204, 232, 247 ; A., 350.5 8 G. Austerweil, Bull. SOC. chim., 1932, [iv], 51, 729; A., 1007.59 A. Brukl and G. Ortner, 2. anorg. Chem., 1931,203,23; A., 238.60 W. C. Johnson and J. B. Parsons, J . Amer. Chem. SOC., 1932, 54, 2588 ;61 W. C. Johnson, J. B. Parsons, and M. C. Crew, ibid., p. 2651 ; A ., 1218.e2 G. Canneri, Met. Itul., 1931, 23, 803; Chem. Zentr., 1931, ii, 3035; A . ,63 P. T. Daniltschenko, J. Gen. Chem. RUSS., 1931, 1, 467; A., 1931, 1381.64 B. Brauner and E. Svagr, Coll.Czech. Chem. Comm., 1932, 4, 49, 239;85 G;. Enders, 2. anorg. Chem., 1932, 205, 321; A,, 69G.A., 1218.455.A., 470, 89482 INORGANIC CHEMISTRY.metal and the trihalide. Aqueous solutions of the dihalides areyellowish and slowly evolve hydrogen-the more rapidly the greaterthe acidity.Anhydrous chlorides of the cerium group metals have been pre-pared from the anhydrous benzoates by the action of a saturatedsolution of hydrogen chloride in dry ether.67The iodide oxidises most slowly.66Lanthana appears to form both a tri- and a mono-hydrate.68Group I V .Metallic sodium reacts sinoothly with warm xylene solutions ofphenyl or alkyl carbonates t o yield pure dry carbon monoxide.69The preparation and properties of carbonyl sulphide and selenide 70and of cyanogen fluoride 71 and osycyanogen, (OCN),,72 have beenexamined.Support has been found for four of the five silicic acids describedby earlier and conclusions have been drawn as to the p ,under which SiO,” and Si,O,” ions can exist in solution.74 Silicavolatilises in supercritical steam (365-410”, 200-350 atm.) andthen attacks various metallic oxides.A number of silicates havebeen synthesised in this way and the process appears to be of con-siderable mineralogical significance. 7 5 Several papers have beenpublished on germanium dioxide, on the hydrated dioxide, and onthe germanates.s6 The behaviour found recalls that of the siliconcompounds.Several salts of 10-tungstogermanic acid have been de~cribed.’~A number of ammines of germanium iodide have been described,78G o G.Jantsch, N. Skalla, and H. Jawurek, 2. anorg. Chem., 1931, 201, 207 ;8 7 P. Brauman and S. Takvorian, Compt. rend., 1932, 194, 1579; A., 584.c 8 G. F. Huttig and M. Kantor, 2. anorg. Chem., 1931, 202,421 ; A., 125.69 S. T. Bowden and T. John, Nature, 1932,129, 833 ; A., 707.7o T. G. Pearson and P. L. Robinson, J . , 1932, 652; T. G. Pearson, P. L.71 V. E. Cosslett, 2. anorg. Chem., 1931, 201, 7 5 ; A., 31.7 3 H. Hunt, J . Amer. Chem. SOC., 1932, 54, 907; A., 482.73 A. Simon and P. Rath, 2. anorg. Chem., 1931, 202, 191; A., 122; Ann.’* G. Jander and W. Heukeshoven, 2. anorg. Chem., 1931, 201,361 ; A., 124.7 5 C. J. van Nieuwenburg and H. B. Blumendal, Rec. trav. chim., 1931, 50,129, 989; A., 322, 1381.7 G A.W. Laubengayer and P. L. Brandt, J . Amer. Chem. SOC., 1932, 54,549, 621 ; A., 483 ; A. W. Lsubengayer and D. S. Morton, ibid., p. 2303 ; A . ,905; R. Schwarz and E. Huf, 2. anorg. Chem., 1931, 203, 188; A., 117; R.Schwarz and F. Heinrich, ibid., 1932, 205,43; A., 584; R. Schwarz and G.Trageser, ibid., 208, 65 ; A., 1099.A., 30.Robinson, and J. Trotter, ibid., p. 660; A., 329.Reports, 1929, 26, 50; 1930, 27, 64.77 A. Brukl and B. Hahn, iMonatsh., 1932, 59, 194; A . , 351.7 * T. Karantnssis and L. Capatos, Conrpt. rend., 1931, 193, 1187; A . , 133BASSETT. 83but no evidence is given that they are definite compounds and thatno reactions have occurred such as those between ammonia andgermanium chloride. 79The reactions and decompositions of stannous nitrate have beeninvestigated,80 and evidence obtained for a tri- and a mono-hydrateof stannic oxide.81The action of ammonia on the tetrachlorides of tin and lead is verycomplex.82 A number of compounds formed in the reaction withthe former or by further treatment of the products have beenisolated, such as SnC14,2NH,, which appears to be a true ammine,the triamino-chloride Sn( NH,),Cl, the nitrilo-chloride SnNC1, andthe nitride Sn3N4.Lead also yields the nitrilo-chloride, PbNC1, anda very explosive compound derived from this by loss of lead chloride.There is still difference of opinion as to whether lead suboxidereally exists.83 All the other oxides of lead have a definite crystalstructure with the exception of the sesquioxide which isand there seems some doubt whether Pb,O, represents a definitecompound.The absorption and removal of oxygen in the reactionsPbO=Pb,O,ZPbO, have been followed by means of oxygen-pressure measurements and X-ray examination of the crystallattices.85 With absorption of oxygen, the lattice of lead oxide ortriplumbic tetroxide persists up to a definite oxygen content,whereupon red lead or the peroxide appears as a second phase.Similarly on removal of oxygen the lattice of PbO, or Pb30, persistsover a certain range without any indications of Pb,O, or Pb,O,.There does, however, appear to be a second, black, modification oft riplum bic tetroxide.Several intermediate stages have been detected in the decomposi-tion of lead nitrate in molten potassium nitrate.86All the alkali-metal fluotitnnates have been prepared and described,and their reactions and solubilities determined.87 A number ofcomplex iodates of titanium have also been described.88Black crystals of Th,N, were prepared by electrically heating to79 Ann.Reports, 1930, 2'7, 65.81 A. Simon and P. Rath, 2. anorg. Chern., 1931, 202, 200; A., 122.82 R. Schwarz and A. Jeanmaire, Ber., 1932, 65, [B], 1443; A., 1100.83 P. Pascal and P. Minne, Compt. rend., 1931, 193, 1303; A., 132; M. LeBlanc and E. Eberius, 2. physikal. Chern., 1932,160, 129; A., 823; R. Frickeand P. Ackermann, ibid., 161, 227; A., 1100.J. A. Darbyshire, J . , 1932, 211 ; A., 326.C. Montemartini and E. Vernazza, Ind. chirn., 1931, 6, 632; A., 351.8 5 M.Le Blanc and E. Eberius, 2. physikal. Chem., 1932, 160, 69; A., 697.86 K. Laybourn and W. M. Madgin, J., 1932, 1360; A., 707.H. Ginsberg and G. Holder, 2. anorg. Ckem., 1931, 201, 193; A., 31; €I.Ginsberg, ibid., 1932, 204, 225 ; A., 351.88 P. R. Ray and H. Snlia, ibid., 208, 200; A . , 109984 INORGANIC CHEMISTRY.2220-2600" a compressed mixture of thoria, grayhi te, and tungstenin a non-oxidising atmosphere containing nitrogen.89Qroup V .The nitric oxide liberated at the anode in the early stages of theelectrolysis of fused sodium nitrite results from the secondaryreaction NaNO, + NO, NaNO, + NO, but although nitritewas completely oxidised to nitrate in 3 4 hours in a current ofnitrogen peroxide a t 315450", only about 5% of nitrate wasreduced by nitric oxide in 6-7 hours a t 315".90 Nitric oxide isabsorbed by alkaline sulphite solutions to yield compounds whichreact like M2S04,N20 since they decompose slowly in cold, andrapidly in hot, water to yield sizlphate and nitrous oxide.Very purenitrous oxide can be obtlained by the action of dilute sulphuric acidon solutions of K,S0,,N20, the gas being washed with 4N-potassiumhydroxide and water. By addition of K2S04,N20 to solutions ofsuitable manganese, cobalt, zinc, or cadmium salts, complex saltswere formed of the type K4M(S04,N,0)3,2H20 or, in the case ofcadmium, IC,M(S04,N,0)2,2H20.g1Phosphorous acid alone is formed when phosphorous oxide isshaken vigorously with excess of cold water. If there is no shaking,local overheating of the acid leads to formation of phosphine, whileinteraction between the acid and thc oxide yields phosphoric acidand yellow, so-called, phosphoriis suboxide.92Both in neutral and in acid solutions, sodium metaphosphatctcombines with water to give orthophosphate only.(NaPO,), iiineutral solution aIso gives rise only to orthophosphate, but in acidsolution pyrophosphate also is formed.93 A incthod for preparingthe well-crystallised hexametaphosphate Na,(PO,),,lOH,O has beengiven.94 The equilibrium €€,PO, + HF H2P0,F + H20 hasbeen studied at 20". H,PO,F is also formed by the action ofhydrogen fluoride on potassium dihydrogen phosphate and on sodiumpyrophosphate, but potassium fluoride and potassium dihydrogenphosphate do not react either in dilute or in concentrated s o l ~ t i o n .~ ~NH,PF, and KPF, can be obtained in good yield by the actionof phosphorus pentachloride on ammonium or potassium fluoride.89 W. Diising and M. Hiiniger, Tech. tuiss. Abh. Osram-Konx., 1931, 2, 367 ;90 J. Szper and K. Fiszman, 2. anorg. Chem., 1932, 206, 257; A., 823.91 H. Gehlen, Ber., 1931, 64, [B], 1267; 1932, 65, [B], 1130; A., 922, 919.92 L. Wolf, W. Jung, and M. Tschudnowsky, Ber., 1932,65, [B], 488; A . , 483.93 S. S. Dragunov and A. N. Rossnovslraja, 2. anorg. Chem., 1931, 200, 321 ;94 P. Pascal and (Mme.) Itkchid, Compt. rend., 1932, 194, 762; A., 483.95 \V. Lange and G . Stein, Ber., 1931, 64, [El, 2772; A., 132.Chem. Zentr., 1932, i, 203; A., 584.A., 1931, 1372BASSETT.85With sodium fluoride reaction is much slower so that only a 5--6y0yield of NaPIF', is obtainable. Ammonium chloride and phosphoruspentachloride yield (PNC12),.g6The mechanism of the thermal conversion of arsenite into arsenateis invariably based on the reaction 5As203 --+ 3As,05 + 4As anddoes not involve direct oxidation by atmospheric oxygen. I n airarsenious oxide is formed, subsequently, from the arsenic liberatedand then undergoes further decomposition.97 Salt-like polyanti-monides or polybismuthides Na,Sb7,xNH, (Na,Bi,,xNH,) are formedby extracting sodium-antimony or -bismuth alloys with liquidammonia.98 When ammonia is removed, the complex anions breakup and a mixture of metallic phases, Sb with NaSb or Bi with NaBi,results.Thesubstance regarded as SbC13,3NH, is really a mixture of ammoniumchloride and, probably, Sb(NH)Cl.The latter yields SbN onextraction with liquid ammonia to remove the ammonium chloride.9gI n the equilibrium 2Bi20, + Bi2S, z3 6Bi + 3SO,, evolution ofsulphur dioxide begins at 150--200" and reaches a pressure of 1 atm.a t 519". Absorption of sulphur dioxide in the reverse reaction ismeasurable at 400O.1A number of internally complex organic derivatives of tervalentvanadium have been prepared and compared with those of thecorresponding iron compounds.2 Conductometric and potentio-metric titrations of solutions of potassium niobate with causticalkali or hydrochloric acid gave no indications of the existence ofortho- or pyro-niobates but only of meta- compound^.^Antimony trichloride gives no ammine with ammonia.Group V I .A nearly quantitative yield of fluorosulphonic acid is obtained bydistilling a mixture of oleum with potassium hydrogen fluoride.The dry acid does not attack gIass.4The m.p.'s, b. p.'s, densities, and surface tensions of selenium andtellurium hydrides have been re~orded.~9 6 W. Lange and G. von Krueger, Ber., 1932, 65, [B], 1253; A., 1100.97 G. G. Reissans, 2. angew. Chem., 1931,44,959; A., 130; E. R. Rushton,'* E. Zintl and W. Dullenkopf, 2. physikal. Chem., 1932, [B], 16, 183; A.,O9 R. Schwarz and A. Jeanmaire, Ber., 1932, 65, [B], 1662.J . Physical Chem., 1932, 36, 1772; A., 810.455 ; Ann. Reports, 1929, 26, 42.R. Schenck and F. Speckmann, 2.anorg. Chem., 1932,206,378; A., 810.A. Rosenheim, E. Hilzheirner, and J. WOE, ibid., 1931,201,162; A., 31.H. T. S. Britton and R. A. Robinson, J., 1932,2265; A., 999.J. Meyer and G. Schramm, 2. anorg. Chem., 1932, 206, 2 4 ; A., 708.P. L. Robinson and W. E. Scott, J., 1935, 972; A., 45486 INORGANIC CHEMISTRY.Selenium dioxide has been found to be a useful oxidising agentfor the preparation of EL number of organic compounds.G Solubilitiesof the normal and acid selenites of sodium and potassium have beendetermined and the composition of the salts and their hydratesestablished - 7Pure chromous iodide has been prepared by heating electrolyticchromium with an excess of iodine in nitrogen or vacuum a t 1150-1200" and removing excess of iodine from the product by heatinga t 2OOO.8The specific action of chromates in inhibiting corrosion of ironis due to the fact that CrO," ion precipitates Fe" ion completely ; theprecipitate consists of the hydrated sesquioxides and has considerableprotective action owing to its gelatinous nature, high specific volume,close adhesion to the iron, etc.Similar protective films form onchromium steels .9The blue " perchromic acid " has hitherto been regarded as a trueperoxidic acid H*O*O*CrO,, of which the pyridine and ammoniacompounds were true salts. It was, however, difficult to understandhow chromium could have the valency of 7 which is required by sucha structure. Strong evidence has now been brought forward forbelieving that the blue compound is not an acid at all but a non-ionicco-ordination complex of the peroxide CrO,, O=Cr<$, with-pyridine, ether, etc., in which the chromium still has a valency of six,with co-ordination number 4.The pyridine compound, on this basis,MolybdGnum sesquisdphide must be prepared by heating thedisulphide under ordinary pressure, not in a vacuum.11 The com-plex cyanide of tervalent molybdenum K4Mo(CN),,2H,0 l2 and thered permolybdates &MOO, and Zn(NH,),MoO, have been prepared,13while the preparation and reactions of the red K,[Mo(CN),( OH),]have been discussed.14 Methods have been given for preparingH. L. Riley, J. F. Morley, and N. A. C. Friend, J., 1932, 1875; A.,533; H. L. Riley and N. A. C. Friend, ibid., p. 2342; A., 1108.J.Janitzki, 2. anorg. Chem., 1932, 205, 49; A., 584.F. Hein and I. Wintner-Holder, ibid., 1931, 202, 81 ; A., 133.T. P. Hoar and U. R. Evans, J., 1932,2476; A., 1093.lo R. Schwarz and H. Giese, Ber., 1932, 65, [B], 871; A., 708; E. H.l1 Guichard, Bull. SOC. chim., 1932, [iv], 51, 563; A., 708.l2 R. C . Young, J . Amer. Chem. SOC., 1932, 54, 1402; A., 584.K. Gleu, 2. anorg. Chem., 1932, 204, 6 7 ; A., 484.l4 W. F. Jak6b end E. Turkiewicz, Rocz. Chem., 1931, 11, 669; A., 1931,1382; W. F. Jak6b and C. Michalewicz, ibid., 1932,12, 667; A., 1100.Riesenfeld, ibid., p. 1868BASSETT. 87several sodium salts of phosphomolybdic and phosphotungsticacids.15 WOC1, is best prepared by passing chlorine over anequimolecular mixture of tungsten and its dioxide at 700-800".It is purified by distillation in vacuum or in a stream of carbondioxide at 200".Careful measurements of a number of its physicalconstants have been made.16 Some reactions of tungsten hexa-chloride have been described.17Mixtures of WC and W2C are formed when the elements are heatedtogether a t temperatures between 1600" and 2500". The former canbe separated from the reaction products by heating in chlorine below600" since the metal and the other carbide are converted into volatilechlorides while WC remains unaffected.18A number of complex salts and ammines of quadri- and sexa-valent uranium have been described, as well as a number of per-uranates .I9Group V I I .Various physical properties of boron and bromine trifluorides andarsenic pentafluoride have been measured.20 A number of complexfluorides of tervalent vanadium and chromium of the typesi&[V(or Cr)F,] and q[V(or Cr)P,,H,O] have been prepared.21They all form cubic crystals.Bromine pentafluoride has been obtained by heating the trifluoridewith fluorine at 200".It is a colourless fuming liquid, b. p. 40.5".Its physical properties and reactions have been examined.22Preliminary details have been given for preparing hypofluorousand fluoric acids.23 Chlorine and bromine form the hydratesCl,,6H20 and Br,,lOH,O, and BrC1,4H20 is more stable than eitherof these.24 It is considered that there is little if any I' ion in aqueousl5 A. V. Rakovski and E. A. Nikitina, J . Gen. Chem. Russ., 1931, 1, 240,l6 W. Reinders and J.A. M. van Liempt, Rec. trav. chim., 1931, 50, 997;l7 A. J. Cooper and W. Wardlaw, J., 1932, 635; A., 352.l8 I. Iitaka and Y . Aoki, Bull. Chem. SOC. Japan, 1932, 6, 108; A., 708.R. RLscanu, Ann. sci. Univ. Jassy, 1930, 16, 32, 459; A,, 1931, 1382;A. Rosenheim and M. Kelmy, 2. anorg. Chem., 1932, 206, 31; A., 708; A.Rosenheim and H. Daehr, ibid., 208, 81; A., 1100.2O 0. Ruff, A. Braida, 0. Bretschneider, W. Menzel, and H. Plaut, ibid.,206, 59; A., 707.21 L. Passerini and R. Pirani, Gazzetta, 1932, 62, 279, 289; A., 795; R.Pirani, ibid., p. 380; A., 902.22 0. Ruff and W. Menzel, 2. anorg. Chem., 1931, 202, 49; A., 133.23 L. M. Dennis and E. G. Rochow, J . Amer. Chem. Soc., 1932,54, 832; A.,24 S. Anwar-Ullah, J., 1932, 1172, 1176; A,, 586; I.W. H. Harris, ibid.,247; A., 1931, 1382.A., 1931, 1382.486.pp. 582, 2709 ; A., 36288 INORGANIC CHEMISTRY.iodine monochloride, but that in hydrochloric acid solution there isconsiderable formation of IC12' i0n.25 It has been stated 26 thatiodine dissociates in ethyl-alcoholic solution to yield uni- and ter-valent ions. The former are precipitated by alcoholic silver nitrate,leaving I(NO,), in solution, and this, with excess of iodine, yieldsINO,. Pyridine and quinoline compounds of these nitrates aredescribed.The isobaric dissociation curve of manganese oxide at about10 mm. shows the successive formation of Mn203, Mn304, and MnO ;nIn,O;;ppears to give the dioxide directly without any intermediatestage. Several manganic dithiocarbamates have been preparedwhich are very similar t o the corresponding ferric compounds.28Evidence is given for the view that Re,O, is thc highest oxide ofrhenium stable under ordinary condition^.^^ Further work has beenpublished on the oxides and other compounds of ter-,30 q ~ a d r i - , ~ ~q~iinque-,~~ s e ~ a - , ~ ~ and septa- 33 valent rhenium, but much of this isin the nature of confirmation of earlier work.Some thermochemicalmeasurements have been made on a few of the septavalent com-pounds . 34Group VIII.The study of the corrosion of iron and other metals has beenplaced on a much more quantitative basis by measuring the absorp-tion of oxygen and evolution of hydrogen which occur during theprocess. Important results have already been obtained in this way.Thus, it is found that when iron or steel corrodes in potassiumA ., 467 ; Ann. Reports, 1930, 27, 72.25 J. H. Faull, jun., and S . Baeckstrom, J . Amer. Chenz. SOC., 1932, 54, 620;26 M. I. Uschakov, J. Qen. Chem. RUSS., 1931, 1, 1258; A., 809.2 7 A. Simon and F. Fehdr, 2. Elektrochem., 1932,38,137 ; A., 468. See alsoI?. Krull, 2. anorg. Chem., 1932, 208, 134; A., 1204.28 L. Cambi and A. Cagnasso, Atti R. Accad. Lincei, 1931, [vi], 14, 71; A . ,133.2s H. V. A. Briscoe, P. L. Robinson, and A. J. Rudge, Nature, 1932, 129,618; A., 585.30 F. ICrauss and H. Steinfeld, Ber., 1931, 64, [ B ] , 2552; A . , 1931, 1382;W. Manchot, H. Schmid, and J. Diising, ibid., p. 2905; A . , 133; F. Kraussand H. Dahlmann, ibid., 1932, 65, [B], 877 ; A., 71 1 ; H.V. A. Briscoe, P. L.Robinson, and A. J. Rudge, J . , 1931, 3218; A., 133; E. Turkiewicz, Rocz.Chem., 1932, 12, 589; A . , 1101.31 W. A. Roth and G. Becker, Ber., 1932, 65, [B], 373; A . , 353.32 W. Biltz, G. A. T,chrer, and K. Meisel, Nach. Ges. Wiss. Cdttingen, 1931,191; Chem. Zcntr., 1932, i, 1070; A., 708; idem, 2. anorg. Chem., 1932, 207,113; A . , 1008.33 H. V. A. Briscoe, P. L. Robinson, and A. J. Rudge, J., 1932, 1104; A . ,685; A. Brukl and K. Ziegler, Ber., 1932, 65, [B], 916; A., 708; W. Biltzand F. Weibke, 2. anorg. Chem., 1931, 203, 3 ; A., 239.34 W. A. Roth and G. Becker, 2. physikal. Chem., 1932, 159, 2 7 ; L4., 4.69BASSETT, 89chloride solutions the proportion of metal which corrodes owing toliberation of hydrogen is considerable for solutions more concentratedthan O-OOlN.35By the interaction of ferric chloride with alkali-metal thio-cyanates in alcoholic solution, complex ferrous thiocyanates only arc'obtained, of the type R,[Fe(CNS),],xH,O. In aqueous solutionferric compounds are obtained and a large number of complex ferricthiocyanates have been described.by boiling with pyridine is reduced to [Fe(C5H5N)4(CNS)2], which,on atmospheric oxidation in chloroform solution, yields[Fe,(C,H,N),,(CNS),] corresponding with Fe,0,.36 The two ferricdithiocarbamates [Me,N*CS,],Pe and [C,H,oN*CS,]3Fe have beenprepared. These are stable towards oxygen and nitric oxide, butthe corresponding ferrous compounds each combine with one mole-cule of this gas.,' Under the influence of sodium ethoxide, ironpentacarbonyl reacts to form ethyl carbonate and Fe(CO)4Na,.38The latter gives the ether-soluble Fe(CO),H, with acid, and this,with concentrated mineral acid, decomposes into tetracarbonyl andhydrogen. It is pointed out that the production of Fe(CO),H, andcarbon dioxide from the pentacarbonyl may be regarded as a form ofhydrolytic water-gas reaction taking place a t room temperature.The' reactions of iron pentacarbonyl with alkali or with organicbases seem to be often very complex, and a number of papers inaddition to the one just cited deal with the matter.39Several iron csrbonyl halogen compounds have been prepared ,derived by substitution either from Fe(CO),X, (X = C1, Br, or I),e.g., (EtS-[CH2],*SEt)Pe(C0)212, or from [Fe(C0)4]3, e .g . ,[Fe(CO),Br,]3.40Carbon monoxide is lost by [Co(CO),], at 55-60', with formationof [Co(CO),],. The cobalt carbonyls show a great tendency towardsThe compoundC5H,N[Fe(C5H5N),(CNS),135 C. D. Bengough, J. M. Stuart, and A. R. Lee, Proc. Roy. SOC., 1930, [ A ] ,127, 42; A., 1930, 712; G. D. Bengough, A. R. Lee, and F. Wormwell, ibid.,1931, [ A ] , 134, 308; A., 27.36 A. Rosenheim, E. Roehrich, and L. Trewendt, 2. anorg. Chem., 1933,207, 97; A., 1009.37 L. Cambi, A. Cagnasso, and A. Tanara, Atti R. Accad. Lincei, 1931, [ui],13, 254; A., 1931, 1382.38 H. Hock and H. Stuhlmann, Chem.-Ztg., 1931, 55, 874; A., 32.39 3'. Feigl and P. Krumholz, Monatsh., 1932, 59, 314; A., 485; W.Hieberand F. Leutert, Ber., 1931, 64, [B], 2832; A., 134; W. Hieber, F. Leutert,and (Frl.) E. Schmidt, 2. anorg. Chem., 1932, 204, 145; W. Hieber, H. Vetter,and H. Kaufmann, ibid., p. 165 ; A., 485; W. Hieber and F. Muhlbauer, Ber.,1932, 65, [B], 1082 ; A., 920.40 W. Hieber, G. Bader, K. Ries, and E. Becker, 2. anorg. Chem., 1931,201, 329; A., 13490 INORGANIC CHEMISTRY.polymerisation and high chemical reactivity. Nickel tetracarbonylis considerably more stable than the iron or cobalt carbonyls. Anumber of derivatives of the cobalt and nickel compounds have beenprepared .41A critical review of recent work on the equilibrium of systemsinvolved in the production of steel has been p~blished.*~ Thesystems Fe-0, Fe-FeO-CaO, Fe-O-C, Fe-Si-0, Fe-MnO, andothers involving phosphorus and sulphur are considered, and atabulated summary is given of the equilibrium constants obtainedby the various workers.The equilibria concerned in the cementation of iron have been thesubject of a careful study.It is concluded from the results thatcarbon vapour is monatomic and that the distribution of free carbonbetween the vapour and the solid phase follows Henry's law.43 Theequilibria between ferrous oxide and silica have been examined inelectrolytic iron crucibles in a vacuum and in pure nitrogen a ttemperatures below 1523". The very interesting fact emerged thatall melts in equilibrium with iron contain some ferric oxide, thepercentage weight of which decreases rapidly from 11.5 as silica isadded.This is presumably owing to an equilibrium 3Fe0 zzFe + Fe203 of the well-known type to which lower valency stagesare subject. On account of this, synthetic and natural fayalite(Fe,SiO,) and all FeO-SiO, mixtures melt incongruently, withseparation of iron. The bearing of the results obtained on petrologyand the problems of slag formation and furnace linings is disc~ssed.~*The distribution of manganese between molten iron and slagowing to the equilibrium FeO + Mn Fe -t MnO has beenexamined, and also the influence of additions of silica and lime.45Two calcium ferrites exist, CaO,Fe,O, and 2Ca0,Fe,03 ; they can beformed from calcium carbonate and ferric oxide a t temperaturesabove 500". 2Ca0,Fe203 does not decompose below 1400", thoughferric oxide evolves oxygen a t 1380".Lime also forms a compoundwith ferrous oxide which is probably 2Ca0,Fe0.46Mixtures of metal and several phosphides are obt,ained by the*l F. Reiff, 2. anorg. Chem., 1931, 202, 375; A . , 239; vCT. Hieber and H.Kaufmann, ibid., 1932,204,174 ; A., 485 ; W. Hieber, F. Miihlbauer, and E. A.Ehmann, Ber., 1932, 65, [B], 1090; A . , 920.42 F. Sauerwald and W. Hummitzsch, Arch. l~isenkiitlenw., 1931-1032, 5,355; A., 340.43 A. Bramley and H. D. Lord, J., 1932, 1041; A., 811.44 N. L. Bowen and J. F. Schairer, Anier. .T. Sci., 1932, [v], 24, 177 ; A., 997.4 5 W. Krings and H. Schackmann, 2. nnorg. Chem., 1931, 202, 99; 1932,206, 337; A., 125, 811; E. Maurer and W. Rischof, I r o n and Rteel I n s t . , May1932, Advance Copy; B., 60%.4 6 J.Konarzewski, Rocz. Cltetn., 1931, 11, 510, 607; A . , 1031, 1010, 1373BASSETT . 91action of hypophosphite on solutions of cobalt or nickel salts.47Crystalline Nip is obtained by the interaction of phosphorus vapourand nickel tetracarbonyl a t 50". An amorphous black solid, prob-ably Nip,, is obtained by bubbling the carbonyl vapour throughphosphorus, either liquid or dissolved in turpentine .48Several new cobaltic ammines have been described,49 and a verylarge number of ruthenium compounds. 50Rhodium dioxide cannot be obtained anhydrous, but in hydratedform it may be obtained pure by the electrolysis of a solution preparedfrom Na,RhCl, and potassium hydroxide. Dark green hydratedRho, separates a t the anode, but attempts to dehydrate it alwaysresult in the formation of Rh203.51 At 210" [BrRh(NH3)5]Br, isquantitatively converted into [Br3Rh(NH,),].The correspondingchlorine and iodine compounds do not behave in this way.52 Aninorganic compound containing no carbon but showing opticalactivity has a t last been found in sodium diaquo-rhodium disulph-amide, Na[ (H20),Rh(NH*S0,*NH),], the cis-form of which has beenresolved into a d- and anNickel, ruthenium, rhodium, and palladium can apparently bereduced to the univalent state when suitable cyanide solutions arewarmed with alkali and 907; sodium hypophosphite solution.54Palladous chloride with many purines and alkaloids forms almostinsoluble compounds from which the bases are easily regenerated.The caffeine and theobromine complexes have the formula R2PdC12.55Much work published during the past year has centred round thequestion whether the valencies of 4-covalent compounds of themetals of Group VIII are planar or directed towards the corners of atetrahedron.The conditions under which a planar configurationis possible have been deduced and can occur with bivalent nickel,palladium, a n d p l a t i n ~ r n . ~ ~ A case of the kind appears to occur withthe glyoximes of nickel, since the benzylmethylglyoxime has beenobtained in two isomeric forms 'of the same molecular weight whichare interpreted as cis- and t~ans-forms.~~4 7 R. Scholder and H. L. Haken, Bey., 1931, 64, [B], 2870; A., 13-1.4 * C. M. W. Grieb and R. H. Jones, J., 1932, 2543.*@ H.J. S. King, J., 1932, 1275; A., 586; T. Das-Gupta and P. B. Sarkar,J . Indian. Chem. SOC., 1932, 9, 79; A., 709.5 1 L. Wohler and K. F. A. Ewald, 2. anorg. Chem., 1931, 201, 145;52 E. Birk and H. Kamm, Siebert Festschr., 1931, 12; A., 2-10.53 F. G. Mann, Nature, 1932, 130, 368; A., 1101.64 W. Manchot and H. Schrnid, Ber., 1931, 64, [ B ] , 2672; A., 32.fi6 J. M. Gulland and T. F. Macrae, J., 1932, 2231; A., 1052.56 L. Pauling, J. Amer. Chem. SOC., 1931, 53, 1367; A , , 1931, 670.6 7 5. Sugden, J., 1932, 246; A., 272.R. Charonnat, Ann. Chim., 1931, [XI, 16, 123; A., 1931, 1383.A., 3202 INORGANIC CHEMISTRY.Investigation 58 of the supposed cis- and trans-isomerides ofPdhX, (where A is an amine and X an acid radical) appears to show,however, that in these cases such isomerism does not occur.Thepink compounds are considered to have the formula [PdAJPdX,,while the yellow compounds are [PdA,X,]. Other workers 59 agreethat there is no cis-trans-isomerism in the case of Pd(NH3),C12 butconsider that both the yellow and the pink form are bimolar.From an X-ray examination of [Pf(NH3),]Cl2,H,O it is deducedthat the four ammonia molecules have a planar configuration roundthe platinum atom. The water molecule is regarded as being at thecell centre and not midway between two platinum atoms as part of asix-point system round the platinurn.6O The solid solution formationsaid to occur between [Pt(NH,),]CI,,H,O and4(Pt(NH3),C1,}Pt (NH,),CI,was not confirmed. X-Ray investigations of the green salt ofMagnus [Pt(PJH,),][PtCl,] show that the two complex ions have thesame structures as those present in [Pt(NH3),]C1,,H20 and inK,PtCl,; both are therefore considered to be planar.The corre-sponding pink salt of Magnus was shown to be very unstable anclits precise nature is still uncertain.62The problem of the isomeric diamminoplatinous chlorides has beencomplicated by the discovery of a third i~orneride.~~ All threeforms are considered to be, probably, structural isomerides and t obe unimolecular and non-ionic. Only one form is supposed to havefour groups arranged round the platinum atom, with no evidenceavailable at present to show whether the arrangement is tetrahedralor planar. For the other two isomerides the early types of structuresc1'H3N>Pt and H3NhPt,+"H3c1 have been revived.The evidenceCl*H,N c1/advanced for this is lengthy, but to the reviewer it seems a retrogradestep. I n the groups *NH,C1 the chlorine is considered to be attachedt o nitrogen which is &covalent with a decet of electrons. It isdifficult to believe that such a structure would have the stabilitxnecessary to account for the behaviour of the compounds, anclweightier evidence seems called for before discarding Sidgwick'scovalency rule for nitrogen. It seems more likely that the threeisomerides are not all monomeric.I n order to account for the remarkable isomerism found amongst5 8 H. D. K. Drew, F. W. Pinkard, G. H. Preston, and W. Wardlaw, J.,59 F. Krauss and K.Mahlmann, Siebert Festschr., 1931, 215; A., 240.Go E. G. Cox, J., 1932, 1912; A., 797.G1 Ann. Reports, 1930, 27, 76.G2 E. G. Cox, F. W. Pinkard, W. Wardlaw, andG. H. Preston, J., 1932, 2527.63 R. D. K. Drew, F. W. Pinkard, W. Wardlaw, and E. G. Cox, ibid., p.1932, 1895; A., 824.988; A., 56%BASSETT. 93the mixed tetrammino-dihalides, e.g., [Pt (NH,),py,JCI,, it has beensuggested 64 that the four linkings to the ammino-groups of thetetrammines are differentiated into two equivalent pairs whichfunction independently, a closer relationship existing between themembers of a pair than exists between either member of one pairand either member of the other. All four linkings are, however,supposed to be of the same kind, and precisely equivalent to oneanother in the sense of the equivalence of the six linkings to hydrogenin the benzene ring.Time alone can show whether such a, viewwill be found satisfactory, but it has been found useful in interpretingthe formation and reactions of a number of c o m p o ~ n d s . ~ ~ ~ 65The view appears to be gaining ground that in 4-covalent platinumthe groups may be grouped tehahedrally about the platinum atomin some cases and be planar in others. To investigate this pointstill further, the two isomeric diquinolinoplatinous chlorides havebeen prepared for the first time in a pure condition.66Systems and Equilibria.Ag-Cu-Mn 67 ; potassium phthalate-phthalic acid-water 68 ; Fe-0, 69 ; CO-N,-H, and the component binary systems 70 ; Pr,(SO,),-TI,SO,-H,O 71 ; Pr2(S04)3-Na,S04-H,0 72 ; Li,SO4-Bi,(S0,),-H,O 73 ; Na2(K,,Rb2,(NH4),,T1,> SO4-Mg(Co,Ni,Zn,Cd)SO,-H,O 74 ;K,(Rb,,Tl,)SO,-CdS0,-H,O 75 ; CaO-Al,03-H,0 76 ; MgCl2-NaNO3-H20 77 ; SrO-As,O,-H,O ; PbO-As,O,-H,O 78 ; Fe-Ni-P 79 ; HCI-S,CI, ; H20-C0,-NH, 8l; K,CO,-KHCO,-H,O 82 ; Fe-Zr 83 ;64 H.D. K. Drew, F. W. Pinkard, W. Wardlaw, and E. G. Cox, J., 1932,6 5 H. D. H. Drew, ibid., p. 2328; A., 1101.66 E. G. COX, H. Saenger, and W. Wardlaw, ibid., p. 2216; A., 1039.6 7 M. Keinert, 2. physikal. Chem., 1931, 156, 291; A., 1931, 1364.6 8 S. B. Smith, J. Aneer. Chem. SOC., 1931, 53, 3711; A., 1931, 1365.6s H. Schenck and E. Hengler, Arch. Eisenhiittenw., 1931-1932, 5, 209;70 T. T. H. Verschoyle, Phil. Trans., 1931, [ A ] , 230, 189; A., 1931, 1370.71 F.Zambonini and S. Restaino, Atti R. Accad. Lincei, 1931, [vi], 13, 650;72 Idem, ibid., 14, 69; A., 132. 73 L. Malossi, ibid., 13, 775; A., 32.74 A. Benrath, 2. anorg. Chem., 1931, 202, 161; 1932, 208, 169; A., 13.3,75 A. Benrath and C. Thonessen, ibid., 1932,203, 405; A., 229.76 G. Assarsson, ibid., 1931, 200, 385; A., 1931, 1370.7 7 A. Sieverts and E. L. Muller, ibid., p. 305; A., 1931, 1370.7 8 H; V. Tartar, M. R. Rice, and B. J. Sweo, J . Amer. Chem. SOC., 1931,R. Vogel and H. Barn, Arch. Eisenhiittenw., 1931-1932,5,269; A,, 221.E. Jiinecke aad E. R d f s , 2. Ekktrochm., 1932,38, 9; A., 229.1004; A., 562.A . , 1931, 1369.A , , 1931, 1381.1205 ; A. Benrath and W. Thiemann, ibid., p. 177 ; A., 1205.53,3949; A., 125.8o H.Terrey and H. Spong, J . , 1932, 219; A., 228.82 Z. P. Staxkova, J . Cen. Chem. RUSS., 1931,1, 747; A . , 229.8a R. Vogel and W. Tonn, Arch. Eisenhiittenw,, 1931-1932,5,387 ; A., 33094 INORGANIC CHEMISTRY.Fe-Co-W ; Fe-Co-Mo 85 ; NH,-H,S 86 ; Na,SiO,-NaF *' ; Fe-GO, 8 8 ; systems SiO,, CaO, and A120, with C S9; Na,O-B,O,-H,O ; Na2S04-A12(S0,),-H,0 91 ; Mg(10,)2-Na103-H,0 ; NaIO,-KIO,-H,O ; KI0,-KC1-H20 ; KI0,-K,SO,-H,O 92 ; KI0,-KN0,-H20 ; Ca(103)2-NaI0,-H20 93 ; KMn04-KBF4-H,0 94 ; Pb(NO,),-(Na,K,Ag,Tl)NO, 95 ; CdC1,-KC1-H,O 96 ; CdBr,-KBr-H,O 97 ;Mg(NO,),-H,O 98 ; Na,S04-H,S0,-H,0 99 ; LiN0,-TlNO, ; CaO-Na20-Al,03 ; SiO,-ZnO-Al,O, ; Ag-Cu-Zn ; MgO-C0,-H,O ;K2C0,-NH3-H20 ; ZnSO,-NH,-H,O ; CuC1,-LiC1-H,O andNiC12-LiC1-H,0 ; CoC1,-LiCl-H,O ; CuSe0,-H,SeO,-H,O lo ;La,(SeO,),-H,O l1 ; Pr,(SeO,),-H,O l2 ; Ni-Zn l3 ; KRe0,-H,O l4 ;NaN0,-KNO, l5 ; KF-AlF, ; LiF-AlF, l6 ; Ca(ClO,),-H,O l7 ;s 4 W. Koster and W.Tom, Arch. Eisenhiittenw., 1931-1932,5,431; A., 456.86 L. Schleflan and C. R. McCrosky, J . Arrber. Chem. Soc., 1932, 54, 193;8 7 H. S. Booth and B. A. Starrs, J . Physical ChenL., 1931,35, 3553 ; A., 340.89 R. Brunner, 2. Elektrochem., 1932, 38, 55; A., 341; E. Baur, ibid., p. 69;Idem, ibid., p. 627; A., 801.A., 340.E. Jiinecke, 2. anorg. Chem., 1932,204, 267; A., 340.A., 341.U. Sborgi, Cfazxetta, 1932, 62, 3; A., 341.91 J. T. Dobbins and R. M. Byrd, J . Physical Clzeuz., 1(331,35,3673; A., 341.92 A. E. Hill and J. E. Ricci, J. Amer. Chem. Xoc., 1931, 53, 4305; A., 341.O3 A.E. Hill and S. F. Brown, ibid., p. 4316; A., 341.94 R. C. Ray and K. K. Chatterji, J., 1932, 384; A., 341.O 5 H. M. Glass,K.Laybourn,and W.M.Madgin,ibid.,pp. 826, 2713; A., 468.H. Hering, Compt. rend., 1932, 194, 1157; A., 469.97 Idem, ibid., p. 1348; A., 574.A. Sieverts and W. Petzold, 2. anorg. Chem., 1932, 205, 113; A., 573.99 T. Okuno andK. Miyazaki, J . SOC. Chem. I n d . Japan, 1932,35,97; A., 57 .1 H. V. A. Briscoe, C. Evans, and P. L. Robinson, J., 1932, 1100; A., 574.2 L. T. Brownmiller and R. H. Bogue, Bur. Stand. J. Res., 1932, 8, 289;3 E. K. Bunting, &id., p. 279; A., 5'74.4 1%. Keinert, 2. physikal. Chew!., 1932, 160, 15; A., 687.5 (Mme.) Walter-LBvy, Compt. Tend., 1932, 194, 1818; A., 697.6 M. P. Applebey and (Miss) M.A. Leishman, J., 1932, 1603; A., 697.7 M. P. Applebey and M. E. D. Windridge, ibid., p. 1608; A., 697.8 H. Benrath, 2. anorg. Chenz., 1932, 205, 417; A., 697.9 H. Bassett and (Miss) I. Senderson, J., 1932, 1856; A., 811.10 G. B. Macalpine and L. A. Sayce, ibid., p. 1560; A., 698.11 J. A. N. Friend, ibid., p. 1597; A., 707.1 2 l d e m , ibid., p. 2410; A., 1083.13 K. Tamaru, Bull. Inst. Phys. Chem. Res. Tokyo, 1932,11, 90; A., 801.14 N. A. Pushin and D. Kovatsch, Bull. SOC. chim. Yougoslav., 1931, 2, 2 5 ;15 J. Ettinger, Rocz. Chenz., 1932, 12, 362; 2. anorg. Chem., 1932, 206, 260;1 6 P. P. Fedot6ev and K. Timoiiev, ibid., p. 263; A,, 810.17 V. S. Egorov, J . Ben. Chew&. Russ., 1931,1, 1266; A., 810.A., 574.A., 801.A., 809, 810BASSETT. 95KC1-PbC12-H20 '8 ; KNO3-NH4NO3-HZO l9 ; CUSO~-COSO~-H20 2o ; carbamide-H202-H20 21 ; Al-Mg-Si 22 ; Al-Mg-Cu 23 ;Al-Cu-Si 24 ; Al-Cu-Fe 25 ; HgBr2-KBr-H20 26 ; Mg0-MgCl2-H20 27 ; NiS0,-CaS0,-H20 2* ; Fe-Mi 29 ; PbO-SiO, 30 ; Fe-Co-C 31 ; Fe-Co-Cr 32 ; Fe-Fe,C-FeS 33 ; KCl-NaC1-H20 34 ;MnSi0,-Fe,Si04 ; FeS-Fe2Si0, 35 ; CaCI2-MgCl2-H2O 36 ; (m4)2s04-Th(SO&-H,O 37 ; MnSOg-Th(SO4)2-H20 38 ; AgNCS-NH3-HZO 39 ;AgNCS-Na"S-H20 ; AgNCS-KNCS-H,O ; AgNCS-NH4NCS-H20 40 ; CaC12-Ca(N03)2-H,0 ; CaC12-Ca( C1O3),-H2O ; SrC1,-Sr(NO,),-H20 ; KN0,-Pb(N03),-H20 41 ; Na20-CaO-B,O,-SiO, 42 ;K2Si03-Na2Si03Si02 43 ; NaN03-KN03-Pb(N03)2.44Is L. J. Burrage, Trans. Faraday SOC., 1932, 28, 529; A., 810.lo E. Janecke, H. Hainacher, and E. Rahlfs, 2. anorg. Chem., 1932,206,357 ;2o H. D. Crockford and D. J. Brawley, J . Physical Chem., 1932, 36, 1594;21 E. Janecke, Rec. trav. chim., 1932, 51, 579; A., 811.L. Losana, Met. Itul., 1931,23,367; Chem. Zentr., 1932, i, 1425; A., 907.z3 A. Portevin and P. Bastien, Cornpt. rend., 1932, 195, 441 ; A., 989.24 G. G. Urazov, S. A. Pogodin, and G. M. Zamoruev, Ann. Inst. Anal. Phys.25 K. Yamaguchi and I. Nakamura, Bull. Inst. Phys. Chem. Res. Tokyo,26 (Mlle.) M. Pernot, Compt. rend., 1932, 195, 238; A,, 913.27 C. R. Bury, E. R. H. Davies, and G. Grime, J., 1932, 2008; A., 913.28 A. N. Campbell and N. S. Yanick, Trans. Faraday SOC., 1932, 28, 657;29 A. KM and F. Pobofil, Iron and Steel Inst., Sept. 1932, Advance copy;30 K. A. Krakau and N. A. Vakhrameev, lieram. i Steklo, 1932, 8, No. 1,31 R. Vogel and W. Sundermann, Arch. Eisenhuttenw., 1932-1933, 6, 35;32 W. Koster, ibid., p. 113; B., 1035.33 T. Sat& Tech. Rep. Tbhoku, 1933, 9, 119; A., 1090.34 E. Cornec and H. Krombach, Ann. Chirn., 1932, [s], 18, 5; A., 1091.3G J. H. Andrew and W. R. Maddocks, Iron and Steel Inst., Sept. 1932,36 C. F. Prutton and 0. F. Tower, J . Amer. C'hem. Soc., 1932,54, 3040; A.,37 A. Rosenheim and J. Zickermann, 2. anorg. Chem., 1932, 208, 95; A.,A., 810.A., 811.Chirn., 1931, 5, 157; A., 907.1932,11, 815; A., 907.A., 913.A., 990.42; A., 1090.A., 1090.Advance Copy ; A., 997.1091.1091.It. M. Caven, J., 1932, 3417; A., 1091.30 F. J. Garrick and C. L. Wilson, ibid., p. 835; A., 457.4O V. J. Occleshaw, ibid., p. 2404; A., 1091.41 W. F. Ehret, J . Amer. Chem. SOC., 1932, 54, 3126; A., 1091.42 G. W. Morey, J . Arner. Ceramic SOC., 1932, 15, 457; B., 1029.43 F. C. Kracek, J . Physical Chem., 1932, 36, 2529.44 I<. Laybourn and W. 31. Madgin, J., 1932, 2582; A., 1205.H. BASSETT

ISSN:0365-6217    

DOI:10.1039/AR9322900074

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

ORGANIC CHEMISTRY.PART ALIPHATIC DIVISION.Radimls and Ions.Electropositive and Electronegative Character .-Great interestattaches to the determination of the relative electro-positivity and-negativity of organic radicals owing to the important influencewhich small differences in polarity can exert on the course ofnumerous reactions. An attempt has been made in a recent papert o place a series of alkyl and aryl radicals in the order of relativenegativity by observing the behaviour of unsymmetrical mercurydialkyls with hydrogen chloride.1 It is assumed that the groupR’ which first dissociates from mercury and combines with thehydrogen ion in solution to form the hydrocarbon R’H accordingto the reaction : R’HgR + HC1+ R‘H + HgRC1, is the moreelectronegative of the two radicals ; that is to say, it has the greaterattraction for electrons and the greater tendency to split off as anegative ion by capturing the electron pair joining it to the metal.The order of increasing negativity amongst the radicals examinedis the following : CH2Ph*CH, < CH,Ph < n-C&,5 < n-C4H, <C,H, < C2H5 < CII, < n2-C6H4C1 < O-C,H&l< $I-c,H@ < C6H5 <m- CH3*C6H4 (p-CH,*C,H, < o-CH,*C,H, < a-nap ht hyl < O-MeO*C,H4<p-MeO*C,H,<CN, and it is seen that the order of the alkylgroups, relative t o one another, is that which has been hithertoaccepted (iso-groups are less negative than the correspondingn-groups, and tert.-groups less negative still), while amongst arylradicals examined the tolyl and methoxy-radicals are more negativethan phenyl, and the chlorophenyl radicals less so.Certain of the broader considerations relating to the classificationof groups are reviewed by R.Robinson in discussing the mechanismsof organic reactions.2 Ordinarily the electropositiveness or negative-ness of radicals is viewed in relation to hydrogen, which is arbitrarilytaken as the standard for comparison. Then R in R-X is consideredt o be electropositive or electronegative according as X receives orloses electrons (by induction or by electromeric change) whenH*X is transformed into R*X. I n this way alkyl groups are alwayselectropositive and NO,, CO, C02Et, and CN are always electro-A., 409.1 1%. S. Kharasch and A. L.Flenner, J . Amer. Chem. b‘oc., 1932, 54, 674;Rapports et Discussions, Inst. Internat. de Chim. Solvay, 1831, p. 423FARMER. 97negative, but it is evident that these designations cannot be appliedto those virtually amphoterk atoms or groups which produceinductive and electromeric effects in opposite directions, unlessthere is some knowledge as to the importance of these effects or oftheir relative magnitude. Unsaturated radicals like vinyland phenyl,although statically nearly always electropositive in character, areelectronegative in relation to the corresponding saturated system ;moreover, owing to structural flexibility and powers of co-operationin electromeric displacements which these groups display, no generalelectrical character can be assigned to them. Atoms possessingunshared electrons (N, 0, C1) and groups terminating in theseatoms exercise generally a negative inductive effect (GI +,0 +--, etc.) and are electronegative, but this can only be statedwith certainty in the absence of electromeric transformations :indeed, where the electromeric displacements of the atom leadnormally to reaction, e.g., when the atom or group occurs in systemssuch as O--Cx=C or @-CzO, the inductive effect acts byopposing or reversing the electromeric effect.The group NH2(not NR,) is electronegative in NB,*CH,*CH3 (dipole N-C), butin NH,Fh, and even more so in PU’H,*COR, the action of the phenylgroup is probably sufficient to reverse the polarity (dipole N-C).Chlorine on the other hand is always electronegative, but to a smallerdegree when it is linked to an unsaturated group, especially if this iskationoid.The high reactivity of organo-magnesium compounds is to beattributed to the tendency towards separation of negatively chargedalkyl groups (the tendency of the metal to assume kationoid functionsnot being thereby opposed) which, possessing only feeble affinityfor their charge, act as energetic anionoid reagents.The alkylgroups of alkyl halides, of alkyl sulphates and of all esters, on theother hand, tend to separate as positively charged ions of kationoidreactivity, thus assisting the halogen atom to form a stable halideRadical Transformations.-Many of the simpler transformationsand isomerisations of organic chemistry can be interpreted asactually occurring by the transfer of Hf, H-, Me-, or electronpairs from one position to another within an organic kation producedIt is doubtful whether the Wiirtz reaction, when appearing in competitionwith organo-magnesium halide formation in the Grignard reaction, can beformulated as simply as R - Mg-Br + R - Br -+R - R + MgBr, inview of the lack of interaction between these two types of organo-halide whenI 3 n6- 6+6+ 6-+ + - + if--heated together (see p. 101).REP.-VOL.ILXIX. 98 ORGANIC CHEMISTRY.-PART I.by the separation of an electronegative group, although the reasonfor these changes is not always plain to see. Thus reactions such asthe dehydration of isobut'yl alcohol to yield n-butylenes in additionto the expected isobutylene, or of tert.-butyl alcohol to give mainlyrearrangement products in any reaction in which hydroxyl is re-moved, can be summarised as due to the series of changes shown in(a)-a series which is analogous to that usually considered to beresponsible for the well-known anionotropic isomerisation of allylicor propenoid compounds, shown in ( b ) :+Ye * * * * * * :A:B:X: ---+ :A:B A A : B : ,+ :Y:A:B: ( a ) ......o f X e .... .... ............ separation tautomerisetion** Shift of electron pair together with the atom or group which it holds. ........ separation shift of 2e :A:B:D:X: ---+ :AiB:D ____f . . . . . OfX0 ..+ye . * * * * * . * .. ..A : B i D -+ :Y:A:BiD ( b )The relationship between various well-known " abnormal " re-actions of organic chemistry is discussed on these lines hy F.C.Whitm~re.~Organo-metallic Compounds.(Continued from Ann. Reports, 1928, 25, 92.)The papers which have appeared in this section since the lastReport are so numerous that reference can be made to only a smallproportion of them.Metal A1kyls.-Lithium alkyls, LiR, which were originally pre-pared by the action of lithium on mercury dialkyls, have beenshown to be obtainable by the action of the metal directly on alkyland aryl halides in ether or benzene.5 Ethyl-lithium reacts withdiethylthallium chloride to yield a true thallium trialkyl, T1Et3,6and by the action of gallium tribromide on methylmagnesiumbromide in ethereal solution the etherate of trimethylgallium,GaMe,,Et,O, is ~btainable.~ Tetraethylgermanium has beenfound to yield on bromination triethylgermanium bromide,GeEt,Br, and from this compound the tri- and di-ethyl oxides andimines of germanium, (GeEt,),O, GeEt,O, (GeEt,),NH, andG-eEt,:NH, and various other alkyl derivatives of germane anddigermane have been directly or indirectly ~btained.~ MagnesiumJ .Amer. Chem. SOC., 1932, 54, 3274; A., 1016.K. Ziegler and H. Colonius, Annaten, 1930, 479, 135; A., 1930, 590;H. Gilman, E. A. Zoellner, and W. M. Selby, J . Amer. Chem. Soc., 1932, 54,1957; A., 728... *.. .... ..H. P. A. Groll, ibid., 1930, 52, 2998; A., 1930, 1302.C. A. Kraus and E. A. Flood, ibid., 1932, 54, 1635; E. A. Flood, ibid.,p. 1663; A., 606FARMER. 99dialkyls and diazyls can be obtained smoothly by the action ofmagnesium on mercury dialkyls and diaryls in ether.Contrary toearlier observations, the latter compounds are soluble in ether.*Observations of the thermal decomposition of sodium andpotassium methyls indicate that t'he reaction proceeds ultimatelyaccording to the equation : 8M*CH, = 6CH4 + M,C, + 6M.Methylsodium is regarded as the salt of a weak acid, the anion ofwhich suffers the fundamental change : 4CH,- --+ 3CH4 + C----,owing to the capture of protons by some of the methide ions at theexpense of others. The stripped quadrivalent ions do not, however,persist, for what is found is the acetylide ion, which is formed pre-sumably by the combination of pairs of quadrivalent ions with lossof electrons : 2C-----+ CiC-- + 6e.9 In the spontaneous de-composition of ethylsodium at the ordinary temperature, the mainreaction can be represented as due to the transfer of a proton fromone ethide ion of every pair to the other, thus effecting the change2NaEt _I, Na,C,H, + C,H,; at 90-loo", however, the ethideions appear for the most part to lose it proton and an electron pair(hydride ion), the main decomposition being then expressed bythe scheme NaEt + NaH + C,Hp, although some ethaneaccompanies the ethylene.10 Study of the thermal decomposition ofdiethylmercury and tetraethyl-lead yields the interesting resultthat when depomposition is effected in ethylene at 250-300", theethylene polymerises, the initial reaction being most probablybetween the latter substance and the ethyl radicals, C,H, +2C,H, = C4H9 + C,H,, followed by C4H9 + 2C,H, = C,HI3 +C2H4, the radicals being ultimately eliminated by mutual interactionor owing to contact with exposed surfaces.llGrignard Reagents.-There now remains little doubt that inordinary ethereal Grignard solutions equilibria always occur inaccordance with the scheme :2MgRHal += MgRz + MgHal, 12, l3The part played by the ether in the formation of these solutions isdue to its solvent power, not only for the organo-metallic com-pounds, but also for the magnesium halides.12 The position ofCompare H.Clilman and R. E.Brown, J . Amer. Chern. SOC., 1930,52,5045; A,, 1931,206.W. Schlenk, jun., Ber., 1931, 64, [B], 736; A., 1931, 719.W. H. Carothers and D. D. Coffman, ibid., p.1254; A., 1930, 757.lo Idem, ibid., 1929,51, 588; A., 1929, 433.11 H. S. Taylor and W. H. Jones, ibid., 1930,52, 1111; A., 1930, 757.12 W. Schlenk and W. Schlenk, jun., Ber., 1929,62, [B], 920 ; A., 1929, 687.An alternative representation, R2Mg,MgHa12 r-" MgRS + MgHal,, is con-sidered less likely to be correct.1s H. Gilman and R. E. Fothergill, J. Amer. Ohern. Soc., 1929,51, 3149; A.,1929, 1432100 ORGANIC CHEMISTRY .-PART I.equilibrium depends on the nature of the halide : thus, for a numberof simple alkyl bromides and iodides the equilibrium is displacedtothe right withincrease in weight of the alkyl group, and substitutionof bromide for iodide has little effect ; with chlorides, the establish-ment of equilibrium occurs very slowly and is complicated by theseparation of magnesium chl0ride.1~9 15 Progress of the reactionin the backward direction has been demonstrated in the case ofphenylmagnesium halides 13, l4 and it has been found that a verysmall amount of magnesium halide is sufficient to initiate reactionbetween triphenylmethyl and magnesium, and to bring about,owing to the continuous regeneration of magnesium halide, completeconversion into the Grignard reagent thus : 2Ph,C + Mg +MgX, + 2CPh,-MgXBoth the alkylmagnesium halides and the magnesium alkylswhich are present in the Grignard solutions are active reagents, anddoubtless the two types of reaction product, zlix., R,C*O*MgHal andR,C*O*Mg*O*CR, which are produced by the action of Grignardsolutions on aldehydes and ketones, owe their respective origins tothe two types of compound.17 The ratio MgR,/(MgR, + MgRX),which can be determined experimentally with some precision,17is considerably modified (increased or decreased) when themagnesium employed is alloyed or mixed with copper, or whenmetallic zinc or salts such as mercuric chloride are,added to thereactants.But the addition of the latter substances has usuallyanother effect, vix., to suppress to a smaller or greater extent theformation of Grignard reagents and correspondingly to favour theWiirtz reaction (yielding hydrocarbons RnR) which commonlycompetes therewith.151 l8 Copper-magnesium alloy, like iodine,forms an excellent catalyst for starting the Grignard reaction, butin most of the instances examined the presence of either substancein significant proportion seriously reduces the yield of Gignardreagent and correspondingly enhances the yield of Wiirtz reactionproducts.19 The ratio R*R/(MgR, + MgRX) is thus increased by theadded substances, but in the case of the Grignard reagent from ally1bromide is notably decreased (from 72% to 6%) by the influenceof copper.There is no reason to think that the Wiirtz reaction as it(CPh,),Mg + MgX,.16l4 W. Schlenk, jun., Ber., 1931, 64, [B], 734; A., 1931, 718.l5 G. 0. Johnson and H. Adkins, J . Amer. Chem. SOC., 1932,54, 1943; A.,The proportion of active reagent present as MgR, is given as 6% for 728.EtI and 84% for BuCI.l6 W. E. Bachmann, ibid., 1930,52,4412; A , , 1931, 79.l7 W.Schlenk, jun.,Ber., 1931, 64, [B], 736; A., 1931, 719.G. 0. Johnson and H. Adkins, J . Amw. Chem. SOC., 1031, 53, 1520; A.,1931, 719.l9 H. Gilman and E. A. Zoellner, ibid., p. 1581; A., 1931, 719FARMER. 101occurs here results from the action of either type of active Grignardreagent on the original alkyl halide employed, since both types ofreagent have been found to be quite unreactive towards the corre-sponding alkyl halides (ally1 is an exception).15 Grignard reagentscan, however, be converted in smaller or greater measure intoproducts of the Wiirtz-Fittig type by the direct action of variousheavy-metal salts, and it is reported that when an arylmagnesiumhalide is added to a suspension of silver bromide a silver aryl isfirst obtained which decomposes into silver and diary1 when thereaction mixture is boiled.*')Organo-magnesium halides can in some cases be prepared freefrom ether by employing benzene as the medium in the Grignardreaction,21 or by avoiding the use of a solvent altogether.22 Theymay also be formed and undergo reaction in situ when a ketone orester replaces the solvent; in this case, however, exchange ofalkyl groups between the reactants may occur in presence of themetal.21 Certain of the lower alkylmagnesium halides can bedistilled (sublimed) in a stream of ether, but there is nothing toshow whether the organo-halides distil as such rather than as themixture in equilibrium therewith: in high vacuum distillationsmagnesium alkyls are obtained.%The reactive properties of Grignard reagents have been furtherstudied.An important property which has received a large amountof attention is the reductive action which manifests itself when thereagents react with certain aldehydes and ketones. Aldehydes andketones which themselves contain branched chains or are employedwith organo-magnesium compounds containing branched chains oftenbecome more or less completely reduced to the correspondingprimary or secondary alcohols-a circumstance which seriouslylimits the usefulness of the Grignard method for synthesisingsecondary or tertiary carbinols but affords in certain cases a con-venient means of reducing the aldehydes and ketones concerned.24Although this reducing action appears to be directly related to thecomplex character of the alkyl groups present in the reactants, nodefinite and exact correlation has been possible between the amountof reduction obtainable and the degree of complexity or the in-2o J.H. Gardner and P. Borgstrom, J . Amer. Chem. Soc., 1929,51, 3375 ; A . ,19301 76.2 1 W. Schlenk, jun., Ber., 1931, 64, [B], 739; A., 1931, 718.22 H. Gilman and R. E. Brown, J . Amer. Chem. SOC., 1930, 52, 5045; A.,28 Idem, ibid., p. 4480; A., 1931, 78; Rec. trav. chirn., 1929,48, 1133; A , ,24 J. B. Conant and A. H. Blatt, J . Amer. Chem. SOC., 1920, 51, 1227; A . ,1931, 206.1930, 76.1929, 676102 ORUANIC CHEMISTRY .-PART I.cidence of the complex groups in one or other (or both) reactants.25It appears to be the case, however, that for the synthesis of tertiaryaliphatic carbinols containing both st'raight and branched alkylgroups, it is best to employ (a-)branched-chain ketones and magnes-ium n-halides.Whether or no each of the organo-magnesiumcompounds present in the Grignard reagent can , without equilibration,effect reduct,ion has not yet been satisfactorily determined, but it hasbeen found that diisobutylmagnesium, which constitutes 75 yo ofthe reagent prepared from isobutyl bromide, reduces benzophenoneto benzyhydrol to the e'xtent of at least 64%, and the Grignardreagent before separation effects reduction to the extent of 84%.26Kohler and his collaborators, in examining the behaviour of keto-oxido-compounds towards Grignard reagents, showed that benzyl-ideneacetophenone oxide, PhCH-CH*COPh, with phenyl-magnesium bromide yields triphenylcarbinol, Ph,C*OH.27 Herethe first step is probably the scission of the benzoyl group as benzo-phenone, which is then transformed into the carbinol.With mostlieto-oxido-compounds a similar result is obtained and manyrelatively heavily phenylated esters suffer fission under the actionof the Grignard reagent. With benzylidene-p-phenylacetophenoneoxide, however, two reactions occur, in one of which both the ketonegroup and the oxide ring are attacked, yielding (I) or its isomeride,and in the other a preliminary scission of phenyl p-diphenylyl ketoneis apparently followed by the reduction of the latter to a pinacol (II).2810-Jp-Substituted ally1 bromides, the structure of which permits ofanionotropic change, can react with Grignard reagents t o giveisomeric olefins (I11 and IV), which are derived by combination ofthe alkyl group from the reagent with the tautomeric forms of theunsaturated kation ; 29 in other cases they react to give hydrocarbons(V and VI), which appear to owe their origin t o a funct,ional ex-25 A.H. Blatt and J. F. Stone, jun., J. Anter. Clzem. SOC., 1932, 54, 1495;A , , 598.26 C. R. Noller, {bid., 1931, 53, 635; A., 1931, 473.27 E. P. Kohler, N. K. Richtmyer, and W. F. Hester, ibid., p. 205; A., 1931,28 E. Bergmenn and H. A. Wolff, ibid., 1932,54,1644 ; A., 616.354.C. Pr6vost and J. Daujat, Bull. SOC. chim., 1930, [iv], 47, 688; A., 1930,1168FARMER. 103change between the reactants : R*CH:CH*CH,Br + MgEtBr -+R*CH:CH*CH,*MgBr + EtBr.30 The Wiirtz reaction is found toaccompany the latter type of reactivity, and both here,30 and wherethe substituted ally1 bromides react directly with magne~ium,~~the coupling of the hydrocarbon radicals may take place in one ormore of three ways yielding substituted hexadienes (VII, VIII, andIX).8 CBR*CH:CH*CH, =+= R*CH*CH:CH,~ -~R*CH:CH-CH,R' R*CH:CH*CH, [R*CH:CH*CH,*];(111.) (V.R*CH:CH-qH,R*CHR'*CH:CH, R;CH2*CH:CH2 CH,:CH*CHR(IV.1 (VI.) [CH,:CH*CHR*],(VII.)(VIII.)(=.IGrignard reagents react with arsenic trichloride and antimonytrichloride t o give trialkylarsines 32 and trialkylstibines respectively,and with a-tert.-amino-nitriles t o yield amino-ketones in additionto amino-hydrocarbons in which the nitrile group has been replacedby the alkyl radical of the Grignard reagent : 33Reference may also be made t o new studies of the action of Grignardreagents on dialkylamides, R1*CO*NR2R3,34 a-~yano-esters,~~carbonic esters 36 and sulphonyl chloride^.^'Compounds of Boron.Boron trifluoride reacts with simple organic compounds ofdifferent types to give addition compounds, and as early as 1891Patein obtained a solid product from acetonitrile and boron trifluoride.The manner of formation and the consbitution of these compounds30 C.PrBvost, Bull. SOC. chirn., 1931, [iv], 49, 1372; A., 1932,41.31 C. Prbvost and G. Richard, ibid., p. 1368; A., 1932,40.33 W. J. C. Dyke and W. J. Jones, J., 1930, 2426,463; A., 1931, 77; 1930,587.33 T.S . Stevens, J. M. Cowan, and J. MacKinnon, ibid., 1931, 2568; A.,1931, 1404.34 (Mlle.)M. Montagne, Ann. Chirn., 1930, [XI, 13,40; A., 1930,460; Compt.rend., 1931, 192, 1111; A., 1931, 831; S. P. Ti, ibid., 1930, 191, 943; A.,1931, 77.35 A. Mavrodin, ibid., 1930, 191, 1064; 1931, 192, 363; A., 1931, 205, 471.36 D. Ivanov, ibid., 1929,189,830; 1931,193,773; A., 1930,61; 1932,43.37 H. Gilman and R. E. Fothergill, J. Amer. Chem. SOC., 1929,51,3501; A.,1930, 462104 ORGANIC CHEMISTRY.--PART I.have recently been studied independently by different workersand it is now apparent that, when boron trifluoride is passed intofatty acids, the esters of fatty (and certain other) acids, ethers,amides, and nitriles, simple addition products are quite frequentlyproduced.Esters such as methyl and ethyl formate, methyl, ethyl and propylacetate, ethyl propionate and methyl benzoate, give distillableliquids or solids which have the general constitution R’*CO,R”,BF, ;acetic acid and propionic acid yield liquids which are distillable withsome decomposition under reduced pressure, and appear to havethe composition (CH,*CO,H),,BF, and (Et*CO,H),,BF, respectively ;acetonitrile yields a distillable solid product, MeCN,BF,, and aceticanhydride a solid Ac,O,BF,.Methyl and ethyl alcohols give withboron trifhoride solutions of high conductivity, due to the formationof addition compounds, R*OH,BF,, which ionise to yield hydrionand the corresponding complex organic ions ; the higher alcohols,however, suffer decomposition to hydrocarbons.Anisole andphenetole give undistillable liquid addition products with borontrifluoride.All the above compounds appear to be capable of formulation inthe manner \O-B-F, in which the link between boron andoxygen is a co-ordinat,e link or semipolar double bond. The additionproduct of boron trifluoride with alcohol has been used as a catalystin converting acetylene into acetals39 and in the esterification ofacetic and propionic acids wit,h various alcohols ; in the former casethe reaction is assumed to be due to the addition of the ions of thecomplex to the hydrocarbon :CHiCH + 2H@ + 2[RO+BF3]- ---+ CH,*CH(OR-+BP,), +x + -/FR/ \FCH,*CH(OR), + 2BP,Boron trichloride 4O reacts vigorously with methyl and ethylalcohols at low temperatures to give quantitative yields of low-melting, volatile alkoxy-compounds, BCI,*OR, BCl( OR),, andB(OR), (R = Me or, Et) ; these are readily hydrolysed by water oralcoholysed (if they contain chlorine) with excess of alcohol.Boron38 H. Bowlus and J. A, Nieuwland, J . Amer. Chem. SOC., 1931, 53, 3835;A., 1931, 1404; G. T. Morgan and R. Taylor, Chem. and Ind., 1931, 869; J.,1932, 1497 ; A., 1931, 1404; 1932, 728.39 J. A. Nieuwland, R. R. Vogt, and W. L. Foohey, J . Amer. Chem. SOC.,1930, 52, 1018; A., 1930, 745; H. D. Hinton and J. A. Nieuwland, ibid.,1930,52, 2892; 1932,54, 2017; A., 1930, 1160; 1932, 728.4 0 E. Wiberg and W. Sutterlin, 2. anorg. Chem., 1931, 202, 1, 22, 31, 37; A.,1932, 258FARMER.105trichloride and the monoalkoxy-derivative BCl,*OR react withmethyl or ethyl ether even at - 80" to form the additive compounds,BC13,R20 and (BCl,*OR),,R,O, but the di- and tri-alkoxy-derivatives,BCl(OR), and B(OR),, do not react therewith even at 100". Theaddition product BCl,,Et,O reacts vigorously with alcohol at- 40" t o yield the compound (BCI,*OEt),,Et,O, which readilydecomposes into the compounds BCl,,Et,O and BCQOEt),. Thethermal decomposition of these substances has been studied.Tri-tert.-butylboron, which has been obtained by the action ofboron trifluoride on tert.-butylmagnesium chloride in ether, is con-verted on oxidation into tert.-butylboric acid. Tri-sec.-propyl-boron resembles the tert.-butyl deri~ative.~~OleJinic, Di-oleJinic, and Acetylenic Compounds.Additive Reactions.-The various factors which enter into con-sideration in connexion with the problems of orientation in olefinicand polyolefinic additions were referred to in last year's Report.The new work on this subject refers mainly to the influence of thegroups present in unsaturated substances on the orientation oftheir addition products, but it is becoming increasingly evidentthat the influence of the reaction conditions (especially conditionsrelating to solvent and to catalytic influences) is of considerableimportance in determining the course of reaction in certain typesof addition.All the evidence available from the literature goes to showthat in the addition of an unsymmetrical molecule XY t o anethylenic hydrocarbon R1CH:CKR2, the ultimate distribution ofthe addenda1 components X and Y, is largely determined by theinfluence of the groups R1 and R2 on the direction of olefinic polar-isation.In general both of the compounds R1*CHX*CHYR2 andR1CHYCHXR2 are likely to be formed, but as yet there is littlein the way of accurate quantitative evidence to show how com-pletely the results of addition can be correlated with the characterof the groups R1 and R2, or how far the observed orientation ingiven examples h independent of the conditions of reaction andof the nature of the addendum XY. With respect to the mannerin which alkyl groups influence the orientation at a double bondR. Robinsone has pointed out that it is doubtful whether theinductive displacements which are usually attributed to alkylgroups (represented by CH+, C2H6+, etc.) can lead directlyto reactivity, the reason being that only unshared electrons can4 1 E.Krause and P. Nobbe, Ber., 1931,64, [B], 2112; A., 1931, 1280.42 " Outline of an Electrochemical (Electronic) Theory of the Come ofOrganic Reactions," p. 16.D 106 ORGANIC CHEMISTRY .-PART I.take part in co-valency formation, and inductive displacements donot appear t o modify the extent of sharing in a bond from thepoint of view of the numbers of quantised electrons associatedwith the atoms in question, although they admittedly disturb t,hesharing electrostatically. Rather must reaction be preceded bya degree of electronic polarisat,ion (symbolised by C==C) in whichelectxons actually dissociate themselves from one of the carbonatoms and become free to be shared with external atoms-thusproviding the means by which anionoid olefinic molecules react.The important effect of alkyl substitution would seem to beclearly shown by a series of additions t o Aa-, AB-, and Ay-unsatur-ated acids recently carried out.43 The extent to which the additionof hypochlorous acid t o each of three isomeric hexenoic acidsoccurs in opposite directions is shown in the scheme :Me*CH:CH*CH,*CH,*CO,HnlC1 ......OH 95%.OH. ..... C1 5%.Et*CH:CH*CH,*CO,HCI...... OH 20%.OH ...... C1 80%.Pra*CH:CH*CO,HOH ...... C1 100%.Here on the basis of the order of inductive effects usually acceptedfor the lower alkyl groups (viz., Pr>Et>Me>H), the orientationsobserved experimentally are completely in accord with expectation,provided it is assumed that the substitution of a carboxyl groupin an alhyl group, as instanced by *CH,*CH,*CO,H and *CH,*CO,H,does not diminish-or diminishes very slightly-the inductive effectof the alkyl group, and that the carboxyl group itself, when attacheddirectly t o an olefinic linkage, possesses little orienting influencecompared with alkyl, or none a t all..Under the conditions of the above reaction and with hypo-chlorous acid as the addendum it is doubtless true that the orientinginfluence of a carboxyl group in the system CH:CH*CO,H is muchsmaller than that of even a methyl group.44 But no general con-clusion can be drawn from the above-cited facts as to the efficacyof the carboxyl group as an orienting influence, either in the case(a) represented by the group *CH:CH*CO,H, in which a conjugated43 G.F. Bloomfield and E. H. Farmer, J., 1932, 2062; A., 930.44 Comparisons (unpublished) made by the Reporter, together with Dr.Bloomfield and Mr. C. Hose, between the orientations assumed by the compo-nents of hypochlorous acid in the systems Mc.CH:CH.CO,H, MeCH:CMe-CO,H,CH,:CMe-CO,H, and CH,:CMe*CO,Et show how important the influence ofthe methyl group can be, but also how materially the carboxyl group canaffect the orientationFARMER. 107system is present, or in the case (b) represented by the system*CH:CH*[CH,],CO,H, in which the carboxyl group is removed toa distance from the ethylenic centre.For in case (a) there is everyprobability that different addenda react in different ways : thushypochlorous acid, being a reagent for the ethylenic linkage p e r se,and having no tendency to add via the carboxyl group, is probablycomparatively little influenced by the latter in respect of the orient-ation assumed ; but addenda such as the hydrogen halides, althoughthese are also reagents for the ethylenic bond p e r se, appear to addpreferably at the ends of the conjugated system, the addition beinginitiated by the attachment of the proton to carbonyl oxygen.Similarly in case ( b ) it has recently been argued 2t44Q that, although inexamples such as the hydration of stearolic acid (X) 45 the observedorientation is improbably due to the influence of the carboxylgroup, transmitted from atom to atom along the carbon chain,CH,fCH,],*CiC*[CH,],*CO,H CH,:CH*[ CH,] ,*CO,HBr..... .H (in toluene) 20H. ..... 2H (57.6%)(X.) 2H ...... 20H (42.4%) H ...... Br (in ether) (XI.)yet it may be due t o the transmission.of this influence through theintervening space (“ field effect ”) : but here a further complicationenters, in that the medium may be such as to transmit the influencereadily or to dissipate it-a state of affairs which has been con-sidered t o receive illustration in hydrogen bromide addition toAc-undecylenic acid (XI),46 where the change from a toluene to anether medium completely reverses the mode of addition.Whetheror no the field effect has the importance thus attributed to it awaitsfuture verification, but there are not wanting indications that thecondition of the carboxyl group-ionised or un-ionised-an havea strong determining influence on orientation, so that it is quiteimprobable that an absolute mode of addition can usually beassigned to a mono-olefinic acid, irrespective of the experimentalconditions and of the character of the unsymmetrical addendum.Ammonia, methylamine, and diethylamine add readily to ethylcrotonate, giving the corresponding p-amino- or p-albylamino-butyric Beaction proceeds at room temperature andliquid ammonia or alcoholic ammonia may be employed. In thecase of ammonia ethyl Pp’-iminodibutyrate is also formed.A study of the lactonisation of A=- and’AB-unsaturated acids has445 R.Robinson, ‘‘ Outline of an Electrochemical (Electronic) Theory of the4 5 (Mrs.) G . M. Robinson and R. Robinson, J., 1926, 2204; A , , 1926, 1024.4 6 J. Walker and J. S . Lumsden, &id., 1901,79, 1191.4 7 K. Morsch, Monatsh., 1932,60, 50; A., 600.Course of Organic Reactions,” p. 32108 ORGANIC CHEMISTRY.-PART I.shown that all acid-y-lactone systems can be interpreted in onegeneral scheme : 48I I I -CH-CC-CO~OH &= ~=C~-&H-CO.OH 4 -+-C~H-#H0-coy-lactoneLactonisation represents an addition reaction in which the com-ponents of the carboxyl group, H and RCO.0, become attachedto the olefinic centre; consequently, analogies are to be expectedwith other additions in which the addendum is of the type HX,but here special limitations are imposed by the bound condition ofthe anionic component of the addendum.Originally R. Fittigand his collaborators had maintained that only AB-unsaturatedacids and allylacetic acid (the only Ay-acid then known) could beconverted by boiling 50% sulphuric acid into y-lactones. Thisgeneralisation, however, is incorrect, since simple Aa-acids giveappreciable quantities of lactone under Fittig’s experimental con-ditions. The variations between different systems can be attributedt o differences in the ratio of the velocity of tautomeric change(a and b ) to that of ring closure (c). Three, possibly four, types ofacid can be distinguished : (i) those in which both changes areslow, but lactonisation is much faster than tautomeric change (acidswith one y-alkyl group and no P-alkyl substituent); (ii) those inwhich lactonisation is fast and tautomeric change slow (acids withtwo 7-alkyl substituents) ; (iii) those in which tautomeric changeis faster than lactonisation (acids with one y- and one P-substituent) ;(iv) ( ? ) those in which tautomeric change is fast and irreversiblein the direction pr --+ ap, no lactonisation being possible (acidswithout y-substituents). No evidence of the re-formation of aAs-acid from a simple lactone by treatment with sulphuric acid orby prolonged heating has been discovered : consequently lacton-isation is formulated as irreversible, but the change, lactone --+ A=-acid, appears to be possible in more complicated systems such aslactonic acids of the paraconic type.The manner of addition of hydrogen chloride to conjugatedolefin-acetylenes resembles that of hydrogen bromide to the con-jugated b u t a d i e n ~ .~ ~ In the latter case the hydrogen of theaddendum always attaches itself (so far as existing evidence shows)its a proton to a terminal carbon atom of the chain, whilst thebromide ion becomes linked at either the second or fourth carbon48 R. P. Linstead, J., 1932, 115; A., 251.49 W. H. Csrothers, G. J. Berchet, and A. M. Collins, J . Arner. Chern. SOC.,1932,54, 4066 ; A., 1231 ; W. H. Carothers and D. D. Coffman, ibid., p. 4071 ;A., 1232FARMER. 109atom. With vinylacetylene (XII) and the isopropenyl-, isobutenyl-and cyclohexenyl-acetylenes represented by f ormulz (XIII), (XIV),and (XV), the hydrogen component of the addendum attaches itselfto the terminal acetylenic carbon atom, whilst the chlorine com-ponent becomes linked at the fourth carbon atom in the case ofvinylacetylene, and at the second in the remaining instances.CH,:CMe*CiCH (XIII.)(XVIII.)The formation of the allene derivative (XVI) is particularly inter-esting.This substance can be isolated as the major product undercertain conditions of reaction, but in the presence of hydrogenchloride it undergoes isomerisation to p-chlorobutadiene so readilythat the latter substance always constitutes part of the reactionproduct. Certain salts reinforce the catalytic effect of hydrogenchloride, and when cuprous chloride is present none of the allenederivative survives.p-Chlorobutadiene has been designated" chloroprene " in analogy with isoprene, and has been made thestarting material for the production of synthetic rubber. Chloro-prene adds a further molecule of hydrogen chloride, yieldingay-dichloro- AP- butene.In the addition of hypochlorous acid to sorbic acid and to p-vinyl-acrylic acid the main influence of the carboxyl group is to decidewhich of the two double bonds of the conjugated system shall beattacked. The ap-unsaturated centre becomes de-activated, andthe anionic charge develops at the %carbon atom. Attachment ofthe chlorine component of the addendum then occurs at the &carbonatom in the manner : 50CH,*CH:CH*CH:CH*CO,H + CH,*CHCl*CH( OH)*CH:CH*C02HCH;CH*CH:CH*CO,H --+ CH2C1*CH( OH)*CH:CHC02HR1R2C:CR3*CR4:CR5*COzHreact with hydrogen in the presence of a platinum catalyst inSorbic acid and its homologues of the series5O G. F.Bloomfield and E. H. Farmer, J., 1932,2072; A,, 930110 ORGANIC CHEMISTRY .-PART I.different ways. 51 At room temperature and atmospheric pressurefour types of addition take place, wiz., ccp-, as-, y&, and orpyS-, thelast of these representing unpreventable attack at both ethyleniccentres simultaneously. The different acids of the series yieldmixtures of the different types of addition product, but examin-ation of the reaction mixtures after partial hydrogenation showsthat hydrogenation follows a different course for each acid; theconstitution of the conjugated compound ( i .e . , the character ofthe substitution in the chain) appears definitely, therefore, to bereflected in the additive mode. It is found, however, that thefigures representing the proportions of the various reduction pro-ducts a t the intermediate stages of reduction are by no means tobe regarded as solely determined by, or affording a true measureof, the structural influences at work in the individual acids; for,although they are reproducible if the catalyst is freshly preparedfrom platinum oxide, when a less active (" aged ") catalyst is usedthe course of hydrogenation (in the case of sorbic acid a t least) 52becomes considerably changed. Thus the nature and extent ofsubstitution in the butadiene chain is not, under the conditions oftemperature and pressure employed, the sole, or apparently themost important, influence in determining the course of reaction.The substitutional or constitutive influence, with its activating ordeactivating tendencies, appears t o be superimposed on a specificcatalytic influence which is capable of activating both unsaturatedcentres of the conjugated system simultaneously.Striking observations respecting selective hydrogenation in tlicnon-conjugated (diolefinic) linoleic acid series are due t o T.P.Hilditch and E. C. Jones.53 I n hydrogenating the unsaturatedglycerides contained in olive and cottonseed oils with a nickel-kieselguhr catalyst it is found that the linoleic groups are verylargely converted into oleic and isooleic groups before the latterare further hydrogenated ; after the linoleo-glycerides have dis-appeared, steady increase in the total saturated acid commences,but development of fully saturated glycerides is relatively slow untilthe final stages of hydrogenation.Further it is found that trioleins(mixtures of oleic and isooleic triglycerides) at first disappear muchmore rapidly than fully-saturated components are produced, indicat -ing that a molecule of triolein, adsorbed by nickel, is desorbed assoon as a single oleic group has undergone hydrogenation. Thusdirect transformation of molecules of trioleh into trktearin a t oneand the same contact with the catalyst does not occur and a singleunsaturated centre only is involved in each effective contact between51 E.H. Farmer and R. A. E. Galley, J., 1932, 430; A., 365.5 2 Idem, Nature, 1933, 181, 60. 53 J., 1932, 805; A., 498PARBEER. 111catalyst and 8r triolein molecule; in this way the hydrogenation ofMerent classes of unsaturated glycerides is definitely selective,the order of reduction being trioleins, di-oleo-compounds, andmono-oleo-compounds.Formudion of Dimerides, Trimerides, and Tetrarnerides.-Olejins.To the list of dimerides and trimerides (including XX-XXIIIbelow), the constitutions of which have been definitely establishedduring the past three years, must now be added dimeric indene(XXIV).541.2.3.4.5..AH2C=CMe2 + H+CH=CMe, +Hz&h2 + H+CH=CPh, -+H,eCHEt + H+CH=CH, jCH3*CMe2*CH:CMe2 (xx.)CH3*CPh2*CH:CPh2 (XXI.)CH,*CHEt*CH:CH, (XXII.)0H,C=CMe2 4- H+C(CMe3)=CMe2 4 CH3*CMe2-C(CMe3):CMe2(XXIII.)The self-addition of mono-olefins, whether of the same or of differentmolecular species, appears to be jointly dependent on (a) thecapacity of a hydrogen atom in one of the reactant molecules (theaddendum) to suffer incipient ionisation in the manner H+C,=C,,and (b) the occurrence of successful polarisation at t'he double bondof the other.55 The process (a) is promoted by electromeric changesin the opposite (usually less-favoured) direction to those utilisedin (b), and polymerisation can only occur to the extent that (a) isachieved; the addition product then retains the double bond ofthe addendum molecule, according to the generalised scheme :s+ s-s - n a+ S+ 8 -CHR1=CR2R3 + H+ CR4ZCR5R6 -+ CH2R1*CR2R3*CR*=CR5R6The formation of addition products by the interaction of styreneand different benzene hydrocarbons in presence of sulphuric54 E.Bergmann and H. Taubadel, Ber., 1932, 65, [B], 463; A., 507.Compare G. S . Whitby andM. Katz, J. Amer. Chem. Soc., 1928,50, 1160; A,,1928, 627; Canadian J . Res., 1931,4, 344; A., 1931, 833.6 5 Compare Ann. Reports, 1930,27,91, 92; 1931,28, 87; E. Bergmann andH. Weiss, AnwZen, 1930,480,49 ; A., 1930,901 ; E. Bergmann, H. Taubadel,and H. Weiss, Ber., 1931, 64, [B], 1493; A., 1931, 945112 ORGANIC CHEMISTRY.-PART I.acid 56 (e.g., CHPh:CH, + C,H, --+ CHPh,*CH,) appears to be ananalogous process.Acetylenes.Acetylene polymerises catalytically at low tem-peratures in the presence of ammonium and cuprous chlorides toproduce a dimeride (vinylacetylene), a trimeride (divinylacetylene),and a tetrameride (probably CH,:CH*CiC*CH:CH*CH:CH,). Thedimeride can definitely yield the tetrameride by self-addition underthe conditions of the reaction and appears to yield the trimerideby combination with a~etylene.~' Polymerisation is limited tocompounds containing the group GCH, consequently the trimerideand the tetrameride are the ultimate products of the reaction.The process is of the same general character as that occurring inthe polymerisation of the mono-olefins and it is noteworthy thatthe reaction ( A ) proceeds in preference to (B) :(A) CH,:CHGC-H + CHiCH + CH,:CH*CiC*CH:CH,(B) CH,:CH*CiCH + H-CiCH + CH,:CH*CH:CH*CiCHThe characteristic mode of dimerisation of conjugatedbutadienoid compounds is Closely related to the Diels-Alder reaction.In last year's Report reference was made t o the elucidation of themanner of dimerisation of cyclopentadiene : during the presentyear the manner of dimerisation in two other outstanding instanceshas been determined.The remarkably stable dimeride of cydo-hexadiene is constituted analogously to dicyclopentadiene, 58 andthe hydrocarbon derived by the combined decarboxylation andDioleJins.I;T. H /.\ /9cH-cH\Doebner 'shydrocarbonpolymerisation of sorbic acid (Doebner's supposed tricyclooctane)is now recognised to be o-propyltoluene.59 The latter mode ofreaction is reproduced in the case of cinnamenylacrylic acid andalso of p-vinylacrylic acid, which yield the aromatic hydrocarbons,o-Ph*C,H4*CH,*CH,Ph and ethylbenzene respectively.All dimerisations of butadienoid hydrocarbons in which the con-stitution of the product has been satisfactorily established yield,56 A.Spilker and W. Schade, Ber., 1932, 65, [B], 1686.5 7 J. A. Nieuwland, W. S. Calcott, F. B. Downing, and A. S. Carter, J . Amer.5 8 K. Alder and G. Stein, Annalen, 1932, 496, 197; A., 938.59 R. Kuhn and A. Deutsch, Ber., 1932,65, [ B ] , 43 ; A., 258.Chem. SOC., 1931, 53, 4197; A., 1932, 40FARMER. 113so far as is known, derivatives of cyclohexene. Hitherto, however,there has been little to indicate how the trimerisation and tetra-merisation of butadienoid compounds proceed.The work ofK. Alder and his collaborators on the trimerides of cyclopentadiene 6othrows some light on the subject. Tricyclopentadiene is formed bythe addition of cyclopentadiene to dicyclopentadiene at the doublebond in the bridged cyclohexene ring of the latter.+Dic yclopentadiene Tric yclopentadieneTwo forms of the trimeride are obtained and since the spatialconfiguration of that portion of the carbon skeleton representedby thick lines in the formula has been shown to be exactly thesame in each case, the isomerism is to be attributed to the alternativespatial arrangements that can be assumed by the cyclopentene ringwith respect to the plane of the adjoining ring. It is probable,indeed, that the two forms of the trimeride arise by addition tothe two known forms of the dimeride respectively.Polymerisationcan go still further to the tetrameride stage. Now since the'' mixed " addition products (XXVI) and (XXVII) can be respect-ively obtained by the addition of successive molecules of cyclo-pentadiene to the compound (XXV) (itself derived by the unionof cyclopentadiene with maleic anhydride) and by the addition ofcyclopentadiene and as-diphenylbutadiene successively to (XXV),Ph(XXVI.) (XXV.) (XXVII.)there is strong indication that the more reactive double bond inany butadiene dimeride or trimeride is normally the one in thebridged cyclohexene ring.A study of the polymerisation of eleven simple butadienes underthe influence of heat or of chemical agents shows that dimerides(one or more in each case) are invariably formed.In some caseshigher polymerides are also formed, but the presence of at leastthree unsubstituted hydrogen atoms on the terminal carbon atoms6 O K. Alder, G. Stein, and others, Annalen, 1932, 496, 204; A,, 938.61 G. S. Whitby and R. N. Crozier, Canadian J. Res., 1932, 6, 203; A., 361 ;G. S. Whitby and W. Gallay, ibid., p. 280; A., 496114 ORGAKIC CHEMISTRY.-PART I.appears to be necessary for the formation of a synthetic rubber.The dimerides are themselves polymerised in the cold by certaininorganic reagents (H,S04, SbCl,, SnCI,, etc.), but there is not,hingas yet to show that their formation constitutes an intermediatestep in the formation of normal rubbers.Refractivity, Condensations, and Structural Mobility.-The simplebutadienoid hydrocarbons, when prepared by the best methodsavailable, show considerable variations in boiling point , density,refractive index, and dielectric constant, although when submittedto the Diels-Alder reaction as a chemical test of homogeneity theyshow no signs of marked heterogeneity. These physical differ-ences, which do not occur in examples where geometrical isomerismis impossible, are attributed to the presence of cis- and trans-forms,or in the case of as-dialkylbutadienes, possibly to the presence ofcis-cis, &-trans, and trans-trans forms.The optical properties ofthe mono- and di-methylbutadienes are also discussed, but fordetails the reader is referred to the original paper.6, The opticalproperties of a number of aryl-polyacetylenes have also beeninvestigated and values for the molecular exaltation due to theCPhiC group obtained.63 These values vary considerably accordingt o the solvent employed, but an average value, EM, 3.29, is recorded.The t rammission of electrical influences through conjugatedcarbon systems is well seen from a number of new examples ofwell-known reactivities.The first of these concerns the formationof oxalyl derivatives by the action of oxalic ester on carboxylicesters or ketones in the presence of sodium or potassium ethoxide.AtH H1-3 p x I 0CHZ-CR'=CH-C<ORIT a R'*CH-C<oR(XXVIII.) (XXIX.)RQ,C*CO*CRR'*CO,R RO,C*CO*CH,*CR':CH*CO,R(XXX.)RO,C*CQ*CH,*CH:CH*CH:CH*CO,RThe detachment of a proton from the a-methylene group of a fattyacid ester (XXVIII) a t the instance of the reagent is rendered62 E. H.Farmer and F. L. Warren, J., 1931, 3221; A., 1932, 141.63 V. ICrestinslri and N. Perssianzeva, Ber., 1931, 64, [B], 2363; A., 1931,141FARMER. 115possible by the juxtaposition of the carbonyl group, so that anoxalyl group is enabled to enter the molecule at this point. Thesame effect obtains if an ethylenic grouping, C:C*, is interposedbetween the a-methylene group and the carbonyl group, as wasdiscovered by A. Lapworth G4 in working with p-alkylacrylic esters(XmX), and has now been shown to occur in the case of sorbicester (XXX).65The formation of aldols or their dehydration product>s by theinteraction of unsaturated aldehydes is an analogous reactivity,and from the recently synthesised P-methylcrotonaldehyde 66(2 mols.) the aldol CMe,:CH*CH(OH)*CH,*CMe:CH*CHO and thecorresponding t riene-aldehyde,CMe :CH*CH :CH*CMe :CH*CH 0,can be successively obtained.67aldehyde together give rise to phenylpentadienal,CHPh :CH*CH:CH*CHO, 68whilst crotonaldehyde (2 mols.) yields an unbranched aldol, doubt-less CHMe:CH*CH( OH)*CH,-CH:CH*CHO.69, Acetaldehyde andcrotonaldehyde, when condensed together, give hexadienal,CH,-[CH:CHI,*CHO, which yields with more acetaldehyde, octa-t rienal, CH,*[ CH:CH ],*CHO. 70 The same type of reactivity doesnot, however, extend to the condensation of aldehydes with un-saturated acids.Thus under the conditions of the Perkin reactionno condensation occurs between benzaldehyde, potassium crotonate,and crotonic anhydride, but in the presence of tert.-bases, benz-aldehyde and crotonic anhydride react to give, not 6-phenyl-AQr-pentadienoic acid, but a-vinylcinnamic acid,Probably here the mixed enolic anhydride,is formed intermediately.Likewise, benzaldehyde and croton-CHPh:C( C0,H) *CH:CH,. 71CHMe:CH*CO*O*C( OH) :CH*CH:CH,,A peculiar type of aldehyde condensation which appears to64 J., 1901,79,1276; see also L. Higginbotham and A. Lapworth, J . , 1923,6 5 W. Borsche and R. Manteuffel, Ber., 1932,65, [B], 868; A., 721.66 F. G. Fischer, L. Ertel, and K. Lowenberg, ibid., 1931, 64, [B], 30; A.,1931, 335.6 7 F.G. Fischer and K. Lowenberg, Annakn, 1932, 494, 263; A., 600;compare K. Bernhauer and E. Woldan, Biochem. Z., 1932, 249, 199; A,,834.R. Kuhn and A. Winterstein, Helv. Chim. Acta, 1929, 12, 493; A., 1929,699.123,1325.69 (Miss) I. Smedley, J., 1911, 99, 1627.70 R. Kuhn and M. Hoffer, Ber., 1930, 63, [B], 2163; 1931, 61, [B], 1977;A . , 1930, 1406; 1931, 1273.R. Kuhn and S. Ishikawa, ibid., p. 2347 ; A., 1931, 1413116 ORGANIC CHEMISTRY .-PART I.proceed in the manner of the Diels-Alder reaction is afforded bythe self-condensation of p-methylcrotonaldehyde in the presence ofsodamide. The aldehyde in this case gives rise to t,he cyclic alde-hyde (XXXI), and citral, with the same condensing agent, givesCMe, CMe,CH, C*CHO \\ CH, CHGHO Ch\,H*CHOOH --+ &Xe CMe C<H\Cg \Cd CH (XXXI.)I I I\ /--+ CMe CH I Ian exactly analogous product ; crotonaldehpde, on the other hand,gives a resin.*'Isomeric Change.-Anionotropic changes closely resembling thatwhich occurs during the isomerisation of the a@-dibromide of hexa-triene( CH,Br*?lH*CH:CH*CH:CH, + B: + CH,Br*CH:CH*CH:CH*CH2Br)have been observed to occur when furfuryl chloride (XXXII) andsorbyl chloride (XXXIII) react with potassium ~yanide.'~ InKCN1- CN*CHMe*CH:CH*CH:CH,CHMe:CH*CH:CHCH,*OBu CHMe:CH*CH:CH*CH,Cl(XXXIII.) CHMe( OBu)*CH:CH-CH:CH,these cases the transferen& of the cyanide radical to the remoteend of the conjugated system appears to reach completion, but inthe instance of the cyanide derived from 5-met hylfurfuryl chlorideand in that of the butoxy-compound derived from sorbyl chlorideby the action of silver butyrate a mixture of isomeric compoundsis obtained.Synthesis oj Ethylenic NitriZes.-Much new information is nowavailable concerning the methods of synthesis of cis- and trans-forms of A=- and AB-ethylenic nitriles, including compounds of the72 T.Reichstein, Ber., 1930, 63, [B], 749; A., 1930, 611 ; T. Reichstein andH. Zschokke, Helv. Chim. Acta, 1932, 15, 249; A., 519; T. Reichstein andG. Trivelli, ibid., p. 254; A., 498FARMER. 117~ e n t e n o - , ~ ~ hexeno-,74 i~ohexeno-,~~ h e ~ t e n o - , ~ ~ and i~ohepteno-~'series.Trienes and Tetraenes.The isolation by R. S. Cahn, A. R. Penfold, and J. L. Simonsen 78of an open-chain triene-carboxylic acid from the wood-oil ofCallitropsis araucurioicles has directed attention to the synthesisof conjugated triene acids.The acid of Simonsen and his collabora-tors, which contained one double bond more than geranic acid,absorbed three mols. of hydrogen on catalytic hydrogenation to givethe already-known dl-tetrahydrogeranic acid. It was therefore adehydrogeranic acid containing the carbon skeleton of geranicacid, and therefore one of seven triene isomerides possessing thenecessary skeleton and differing from one another only in the positionof the double bonds. The most probable formula for the acid wasthe fully-conjugated one, CMe,XH*CH:CH*CMe:CH*CO2H, in spiteof the fact that no addition product with maleic anhydride had beeno b t aim ble .Now the introduction of a methyl group into the p-position duringthe synthesis of a conjugated acid can usually be achieved by sub-mitting such a ketone as mesityl oxide to the Reformatsky reaction ;but here the ketone requisite for the production of a terminal iso-propylidene group in a conjugated chain was that homologue of thewell-known crotylideneacetone which should be capable of synthesisfrom F.G. Fischer, L. Ertel, and K. Lowenberg's P-methylcroton-aldehyde.CMe,:CH*CH:CH*CO*CH,,by Fischer and Lowenberg was followed by its submission to theReformatsky reaction with bromoacetic ester. Thus was obtaineda hydroxy-ester, CMe,:CH*CH:CH*CMe( OH)*CH,*CO,Me, from whichby dehydration and hydrolysis a solid dehydrogeranic acid identicalwith Cahn, Penfold, and Simonsen's acid was derived.79 Thisacid was accompanied by an oily acid which apparently representedThe successful synthesis of this ketone,7 3 P.Bruylants and G. Jmoudsky, Bull. Acad. roy. Belg., 1931, [v], 17,1161; A., 1932, 257.74 P. Bruylants and L. Ernould, ibid., p. 1174; A., 1932, 258; R. A. Letchand R. P. Linstead, J., 1932, 443; A., 371 ; P. Bruylants, Bull. SOC. chim.Belg., 1932, 41, 309; A., 1119; A. Dewael, ibid., p. 318; A., 1119.75 J. Baerts, ibid., p. 314; A., 1119; P. Bruylants, Bull. Acad. TOY. Belg.,1931, [v], 17, 1008; A., 1931, 1403; P. Bruylants and L. Ernould, ibid., p.1027; A., 1931, 1403.7 6 P. Bruylants, Bull. SOC. chi,m. Belg., 1932, 41, 333; A., 1119.7 7 G. Festraete, ibid., p.327 ; A., 1119.7 8 J., 1931, 3134; A., 1932, 144.79 Annalen, 1932,494,263 ; A., 600118 ORUANIC CHEMISTRY.-PART I.or contained a geometrical isomeride of the first, since it gave di-methylheptatriene on decarboxylation.The same synthesis was effected independently by R. Kuhn andM. Hoffer,so likewise employing the diene ketone derived fromP-methylcrot onaldehyde. Here, however, the Ref ormat sky productyielded, when dehydration was effected before hydrolysis, a mixtureof Cahn, Penfold; and Simonsen's acid (m. p. 186") and a solidisomeride (m. p. 137") thereof; but when hydrolysis and dehydra-tion were effected in one operation, only the lower-melting isomeridewas obtained. The two acids show almost identical absorptionspectra and doubtless differ in the geometrical configuration aboutthe ap-double bond.I h h n and his collaborators draw attentionto the approximately constant difference in melting point betweenall such pairs of trans- and cis-isomerides belonging to the mono-olefin, diene, and triene series of monocarboxylic acids respectively.Triene acids analogous to the above but containing the ring ofionone have also been derived by submitting p-ionone to the Re-formatsky reaction with bromoacetic ester and hydrolysing the trieneester (XXXIV) thereby immediately obtained.81 The acids (solidand liquid) in this case also were probably geometrical isomerides.A related synthesis has been effected by treating a-ionone withallylmagnesium bromide, the product being the hydroxy-hydro-carbon (XXXV), from which the corresponding trimethylcgclo-hexenylmethylhexatriene is obtained on dehydration.The alcohols corresponding to Kuhn and Hoffer's n-octatrienaland n-decatetraenal have been obtained by reducing the aldehydeswith aluminium isopropoxide.Both n-octatrienol,CH, *CH :CH*CH: H,HO*CH,*CH: 8 Hand n-decatetraenol, CH,*CH:CH*CH:QH, like sorbyl alcohol, arccrystalline solids unstable in air.s2HO*CH,*CH:CH*CH:CHso Ber., 1932, 65, [B], 651 ; A., 600; see also R. Kuhn and H. Roth, ibid.,81 P. Karrer, H. Salomon, R. Morf, and 0. Walker, Helv. Chim. Acta, 1932,82 T. Reichstein, C. Ammnnn, G. Trivelli, and others, ibid., p. 261;p. 1285; A., 1111.15, 878; A., 852.A., 496FARMER. 119Several interesting considerations arise out of the observed be-haviour of polyene-carboxylic acids on reduction.As was shownby J. T. Evans and E. H. Farmer,83 the reductive behaviour ofsorbic acid when treated by metals in aqueous media varies with theacidity or alkalinity of the medium, but both aP- and as-dihydro-genated (A?- and AP-dihydro-)products are always formed. Asimilar production of isomeric dihydro-acids by a@- and terminaladdition (possibly also by as-, etc., addition in the case of trienesand higher polyenes) is generally to be expected with all conjugatedpolyene-monocarboxylic acids, although theoretical considerationsindicate that the proportions must vary with the character of thesubstitution in the polyene chain and in some cases one of theforms may be absent, or present in but small amount, or may even beso unstable as to suffer double-bond migration immediately afterproduction.Although in the sorbic acid series dual modes of re-duction have been shown to apply generally,a4 experiments by R.Kuhn and A. Winterstein on the reduction of aw-diphenylpolyeneshave given only terminally additive products ; 85 also from the (mono-meric) reduction products of the triene- and tetraene-acids,CH,*[CH:CH],*CO,H and CH,*[CH:CH],*CO,H, only terminaladdition products have as yet been isolated.86 A noteworthypoint here, however, is that the Akl.ihydro-derivative of thetriene acid suffers transference of the conjugated system (as awhole) towards the carboxyl group when heated with alkali underthe usual conditions of the py,ap-change :CH,*CH,*[CH:CH],*CH,*CO,H --+ CH3*CH,-CH2* [CH:CH],*CO,HIn these reductions, as in those of the ao-diphenylpolyenes andindeed of all other reductions of polyene systems so far described,there has been no indication of the production of geometrically iso-meric polyene-reduction products.In all terminal additions thedistinction between cis- and trans-forms appears to be obliteratedduring the reaction, for reasons which are quite intelligible havingregard either to electronic or to Flassical representations of thevalency changes which occur in the processes; 87 moreover, so83 J . Soc. Chern. Ind., 1928,47,268; J., 1928, 1644; A., 1928,868.84 Ann. Reports, 1930, 27, 87.85 Helv. Chim. Acta, 1928,11, 123; A., 1928, 281.8 6 R.Kuhn and M. Hoffer, Ber., 1932, 65, [B], 170; A., 365.8 7 Compare E. H. Farmer and W. M. Duffin, J., 1927,405; A., 1927, 448;E. H. Farmer, B. D. Laroia, T. M. Switz, and J. F. Thorpe, ibid., p. 2937; A.,1928, 151; E. H. Farmer and F. L. Warren, J., 1929, 897, 901; A., 1929,812120 ORGANIC CHEMISTRY.-PART I.far as present evidence shows, the resulting‘ configurations aboutthe individual double bonds are all of tram-character.s8Pol yenes .Bixin and Crocetin.-The foregoing consideration respectingthe geometrical form of reduction products is of importance inconnexion with the inter-relationship of bixin and p-bixin, the latterof which can be converted into the former by the addition and re-moval of iodine. The probability that the two substances arecis-tram‘ isomerides seemed somewhat diminished by the fact thatQH:CH*8:CH*CH:CH*~:CH*CH:CH*C! :CH*CH:CH*F:CH*CH:?HC0,Me Me Me Me Me CO,HQH:CH*Q:CH*CH:CH*8:CH*CH:CH*CH:Q *CH:CH*CH:v*CH:rHCO,Me Me Me Me Me CO,Hthe formation of isocarotin from P-carotin, which likewise occursby the action of iodine, involves no cis-trans rearrangement : butin the latter case strictly stoicheiometrical proportions of iodine arefound to be necessary for the conversion, whereas in the former onlya trace of iodine is required.The two bixins give on reductiondihydro-compounds which are identical and of which the methylesters are identical: hence it appears that they are geometricalisomerides, but there is no indication as to whether only one, ormore than one, cis-unit is present in the molecule of bixinAnalysis of the absorption spectra of the various compoundsstrongly indicates that dihydrobixin arises by the terminal additionof hydrogen to the parent compounds, and in such a process geo-metrical considerations indicate that homogeneous trans, trans... . . -and cis, cis.....-systems ( A and C respectively) can alike pass intohomogeneous trans, trans.. . .-chains.Bixin (Kuhn and Winterstein, 1925) (XXXVI.)Bixin (symmetrical formulation) (XXXVII.)The case of j3B’-diphenylmuconic acid, ho-ever, appears a t present toafford an exception (Farmer and Duffin, Zoc. cit.). One of the two knowngeometrically isomeric forms of this acid yields the cis-dihydro-acid on reduc-tion with sodium amalgam, and the other a mixture of cis- and trane-dihydro-acids.This result may mean that the addition (owing t o the influence of thephenyl groups) does not take place terminally, or that certain types of sub-stitution can exert a determining influence on configuration during the passagefrom the intermediate (non-double bonded) stage of reduction to the final stagea$ which reducocl prodacts of definite reomotrical form appearFARMER. 121If trans-linkings usuahy occurred in the form (D) [obtainable from(A) by rotation about the single bonds], the appearance of cis-linkings in the building up of dihydro-polyenes might be geometricallyconceivable ; but such configurations in conjugated compounds-atleast in the crystalline condition-have not yet been observed andthe X-ray analysis of trans, tra ns....-p olyenes agrees better with theform (A).89 At present there is no reason to assume, as has formerlybeen done for glutaconic acid and muconic acid, that in long-chain polyenes all distinctions between cis- and trans-configurationsabout the individual double bonds disappear, and the revival byD.Riidulescu90 of electronic formulae (other than as reactionformulae) in which distinctions between cis- and trans-configurationsdisappear 91 has no experimental justification or demonstratedprobability-although the synthesis, for instance, of the 72 geo-metrical isomerides of 1 : 14-diphenyltetradecaheptaene seems asomewhat remote event.The reported non-equivalence of the carboxyl groups in bixinmay be due therefore to a single cis-linking placed unsymmetricallyin the chain, and the four methyl substituents, the positions of whichhave not yet been determined, may well occupy symmetrical positionsin the chain as in (XXXVII),s9 rather than as in (XXXVI).Ac-cording to (XXXVII) bixin would represent the middle fragmentof the lycopene molecule as formulated by P. Karrer and hiscollaboratorsg2 and it is possible that bixin is derived fromlycopene, or a polyene closely related thereto, by oxidativedegradation.A remarkable feature of dihydromethylbixin and of the di-methyl ester of crocetin is that these substances are smoothly de-hydrogenated to p-methylbixin and to the dimethyl ester of crocetinrespectively by secondary and tertiary amines in the presence ofair ; 93 both substances, moreover, yield vivid colour reactions whentreated with caustic alkali in pyridine, the coloured solutions(emerald-green and indigo-blue respectively) yielding the dehydro-genated products when shaken with oxygen.This behaviour isrelated to the capacity of glutaconic ester, As-dihydromuconicester, and other allied substances' to give deep yellow or red sodio-derivatives with alcoholic sodium ethoxide, or with caustic soda-89 R. Kuhn and A. Winterstein, Ber., 1932,65, [.€?], 646; A., 618.90 Ber., 1931, 64, [B], 2223; A., 1931, 1351.91 Compare G. Wittig and W. Wiemer, Annalen, 1930, 483, 144; A.,93 Helv. Chim. Acta, 1930,13, 1084; A., 1930, 1422.93 R.Kuhn andP.J.Drumm,Ber., 1O32,85, [B], 1468; A., 1138.1931, 92122 ORGANIC CHEMISTRY .-PART I.pyridine (aq.), and is doubtless due to the formation of enolic sodio-derivatives in the groups *CH:CH*CH,*CO,R.Sodio-glutaconic ester (yellow) Sodio-dihydromuconic ester (red)I-(blue)Dihydromethylbixin(orange)Dimethyl ester of dihydrocrocetin(yellow ) I1 CH:CH*CMe:CH*CH:CH*CMe:CH*CH:C( 0 M e ) d a(green)The auto-oxidation of dihydromethylbixin in the presence of causticsoda results rapidly in the removal of the two hydrogen atoms fromthe or-carbon atoms according to the equation :C26H,404 + 0, + C,,H& + H202.94Lycopene and p-Carotene.-Lycopene, C,H,,, yields on gentleoxidation with chromic acid a C8-ketone, CMe,:CH*CH,*CH,*COMe,the balance of the molecule being represented by a new aldehyde,lycopenal, C32H420, which contains an isopropylidene group and tendouble bonds in the carbon chain.g5 Spectroscopic examinationof the aldehyde and its oxime indicates that the aldehyde group isprobably conjugated with the double bonds of the chain as requiredby the formula (XXXVIII) suggested by P.Karrer and his col-laborator~,~~ but the evidence here is not decisive and does notexclude the possibility that lycopenal possesses a structure corre-sponding to the lycopene formula (XXXIX), which, like (XXXVIII),fits the facts so far known about the lycopene constitution.[ CMe2:CH*CH2*CH2.CMe:CH*CH:C-H*CMe:CH*CH:CH*CMe:CH*CH:],(XXXVIII.)CMe, :CH*CH, *CH,*CMe :CH*CH,*CH,*CMe:CH*CH:CH*CMe :CH*GHCMe, CH CH :CH*CMe :CH*CH :CH*CMe CH CM : CH*CMe: CH CH(XXXIX.)94 R.Kuhn, P. J. Drumm, M. Hoffer, and E. F. Moller, Ber., 1932, 85, [B],s5 R. Kuhn and C. Grundmann, ibid., p. 898; A., 749.D6 Helv. Chim. Acta, 1930,13, 1084; 1931,14, 435; A., 1930, 1422; 1931,1785.597FARMER. 123It has been shown that p-carotene suffers oxidation on carefultreatment with chromic acid to yield a p-oxycarotene which appearsto have the empirical formula C40H5803, containing without doubt onep-ionone ring undamaged-a feature which results in the preserva-tion of the growth-promoting effect characteristic of p-carotene.With a larger amount of chromic acid a second oxidation product,apparently C,H,,O,, is obtained which does not appear to bederived by way of P-oxycarotene.This substance, to which thename of p-carotenone has been given, appears to be derived by fhespecific oxidation of the double bonds of the p-ionone rings inp-carotene as shown in formula (XL).97Rubber.Natural Rubber.-A series of investigations on the structure ofnatural rubber has been carried out by T. Midgley, jun., and A. L.When cr@pe rubber is rapidly distilled, the distillateobtained, although consisting largely of isoprene, dipentene, andheveen (C,,-hydrocarbon), contains a number of other hydrocarbonsin smaller or greater quantity. All of the recognisable products?containing from five to ten carbon atoms in the molecule, werefound to possess structures which could have been derived from therubber unit, --C---?=C-C- or ---C-Q_b--C--, by simpleC Coperations (hydrogenation, dehydrogenation, double-bond migration,self-addition). From the proportions of the variws productsobtained, it appears that there is little tendency for the carbonskeleton of the rubber molecule? as represented in the Pickles formula,I--- C-~=C-~~-C-?=C-C-j-C-r=C-C .--C C Cto suffer fission at points other than those single bonds which arefarthest removed from the double bonds.As the result of a study of the precipitation of rubber from analcohol-benzene medium it is claimed that individual long-chaincomponents of rubber can be characterised by the temperature a twhich precipitation occurs in a slowly cooled solution of standardcomposition. By means of this technique rubber is found to consist97 R.Kuhn and H. Brockmann, Ber., 1932,65, [B], 894; A., 749.98 J . Amer. Chem. SOC., 1929, 51, 1215; A., 1929, 702; ibid., 1931, 53, 203;A., 1931, 357; (with M. W. Renoll) ibid., p. 2733; B., 1931, 853; ibid., 193254, 3343, 3381 ; A., 1036124 ORGANIC CHEMISTRY .-PART I.to the extent of over SOY; of a single component; this is ac-companied by more soluble but less definitely characterised com-ponents. Milled rubber, on the other hand, is found to be made upof a continuous series of undefined components without a singlepredominating individual.An interesting contribution to rubber chemistry is afforded by anew investigation of the action of hydrogen peroxide on solutionsof rubber in chloroform-acetic acid.99 Extensive oxidative hydr-oxylation takes place at the double bonds of the rubber molecule,but some of the double bonds appear to survive, since the productis still unsaturated, and, after acetylation, further hydroxylationcan be brought about with hydrogen peroxide.During acetylation,however, some of the hydroxyl pairs appear to lose water to yieldoxide rings, and some of the methylene groups of the rubber unitto suffer replacement of hydrogen by oxygen. For details of thetransformations, which include the production of two dibasic acids,reference must be made to the original paper, but the main changesare shown in the following scheme, in which the primary hydroxyl-ation product is represented on a C,, basis, this being the smallestmolecular magnitude compatible with the analytical results obtained.Rubber H,O,i C50H,6(OH)16 --% C48H8,014(CH0)2&/' JHNO*c50H7 606(OAc)4 c48H86014(c02H)2 jH*@ %.%C~OH~~O~,(OH)~(OA~), C50H7606(0H)4 (CHo)Z48 74 1 (saturated)IC50H56016(0H)1Z(saturated)IJ.C48H7408(C02H)2Similar operations have been carried out with gutta-percha andbalat a.Artificial Rubber.-Owing to the fact that chloroprene ( p-chloro-butadiene), which can readily be prepared from acetylene in a stateof purity and in large quantity, polymerises about 700 times asrapidly as isoprene, it can be used as a starting material for theproduction of synthetic rubber.l Within ten days, under ordinaryconditions, chloroprene polymerises into a transparent resilient9g J.A. Mair and J.Todd, J . , 1932, 386.1 W. H. Carothers, I. Williams, -4. RI. Collins, and J. E. Kirby, J . Amer.Chem. SOC., 1931, 53, 4203FARMER. 125mass resembling vulcanised rubber; but if polymerisation is in-terrupted before it has proceeded to completion, a soft plasticprodvct (a-polymeride) resembling unvulcanised rubber is obtained.Under the action of heat the oc-polymeride changes rapidly into thep-polymeride, and by other means volatile (p)-, granular (a-), andbalata-like polymerides can be formed. The conversion of chloro-prene into p-polychloroprene is stated to proceed rapidly in aqueousemulsion, yielding a synthetic (vulcanised) latex of smaller particlesize than natural latex.With regard to the constitution of polymerised chloroprene itappears probable that the p-polymeride is the analogue of naturalrubber and should be represented by a formula strictly analogousto that of Pickles,* * * -CH~*~:CH*CH,*CH,*F:CH.CH,*CH,.Q:CH*CH,- * *In conformity with this formula it is extremely resistant to alkalis(as also to hydrochloric acid, hydrofluoric acid, ,and many otherreagents), is less reactive than natural rubber towards ozone, andyields succinic acid on oxidation.But these observations do notreveal whether a uniform attachment of chloroprene units in themanner 1 : 4-1 : 6, etc., obtains, or whether inverted unions ofthe type 1 : U : 1 or 4 : 1-1 : 4- occur in the chain. Suchinversions probably do not occur to any considerable extent insyntbetic isoprene rubber, since the behaviour of the latter toozone is normal,2 and here also the X-ray pattern indicates that thereis greater freedom from irregularities than in other synthetic rubbers.Of other known bay-chlorobutadienes, y-chloro- P-methylbutadieneis the only one likely to serve as a precursor of rubber.In this casepolymerisation occurs as rapidly as with chloroprene and theproduct is vulcanised by heat alone.3 When a second methyl groupis introduced into the chloroprene molecule, as in y-chloro-ccp-di-methylbutadiene, the ease of polymerisation is greatly reduced, butis still superior to that of isoprene.The nature of the product obtained by the pyrolysis of sodiumrubber (polymerised isoprene), in comparison with those obtainedfrom natural rubber, is held to indicate that the position of themethyl groups and the character of the unsaturation in methylrubber both differ from those in natural r ~ b b e r .~ The products fromsodium rubber are on the whole more saturated, showing a decreasea Compare R. Pummerer and A. Koch, M e d e r ’ s “ Handbuch der Kaut-W. H. Carothers and D. D. Coffman, J. Amer. Chem. SOC., 1932’54,4071;c1 c1 c1schukwissenschaft,” 1930, p. 270.A., 1232. ‘ T. Midgley, jun., A. L. Henne, and A. F. Shepard, ibirE., p. 381 ; A., 276126 ORGANIC CHEMISTRY .-PART I.i n the amount of isoprene and dipentene and an increase in theamount of pentenes and of saturated hydrocarbons present (saturatedhydrocarbons are absent from the natural rubber distillate).The pyrolysis results for sodium rubber agree with the arrange-ment of carbon atoms, but are incompatible with the regularrecurrence of double bonds shown in the carbon skeleton :Titration of sodium rubber with bromine indicates the presence ofone double bond per C,H, unit, and the ozonide of sodium rubbercorresponds in composition with [C5H8O3’Jn.The ozonide does not,however, break down into simple products on heating with waterand it is concluded that the sodium rubber molecule is a modification,possibly cyclised, of that shown above, the modification resultingin the presence of one chemically weak bond per C,H, unit.Polylsaccharides.Length of Chain and Molecular Weight .--Since the cryoscopicmethod of determining the molecular weight of polysaccharides hasin many cases proved to be unreliable, considerable interest attachesto the results afforded by purely chemical methods of estimation.A theoretically simple way of determining the length of chain of thosecomplex open-chain substances which are built up of recurrent unitsconsists in determining the percentage degree of occurrence of theterminal units (one or both), since these will usually permit ofdifferentiation from the intermediate units of the chain.Themethod will apply whether the complex substances in question ariseby the additive polymerisation of olehic units (polystyrenes, rubber,etc.) or by the condensation-polymerisation of hydroxylated mole-cules (polysaccharides), so long as the ends of the chain are notjoined. The practicability of the method, however, dependsentirely on the reactive capacities of the terminal units whilst stillforming part of the chain, on the facility with which one or other ofthe terminal units (or characteristic fragments thereof) can besegregated by quantitative scission of the chain, or on both properties.Thus if cellulose be represented, according to the conception whichhas gained almost general acceptance, as built up by the union ofglucosidically-linked p-glucose units (XLI), one of the terminal unitswill differ from the other and from the intermediate members of thechain in the number of non-glucosidyl hydroxyl groups capable ofmethylation (XLII).I n the same way, if starch and glycogen berepresented as built up of cc-glucose units (XLIII and XLIV), andinulin of fructofuranose units (XLV), the terminal C,-units will iFARMER.127every case be capable of differentiation from the intermediate units,and from one another.CH,*OHH OHCH,-OH -- H OHCH,-OHH OHc HxCH2-OH 1(XLV.)The method was found to be applicable equally to cell~lose,~starch (both amylose and amylopectin portions),6 glycogen,' andinulin.8 In the first three polysaccharides the non-reducing5 W. N. Haworth and H. Machemer, J., 1932,2270; A., 1022.6 E. L. Hirst, (Miss) M. M. T. PIant, and (Miss) M. D. Wilkinson, ibid., p.7 W. N. Haworth and E. G. V. Percival, ibid., p. 2277; A., 1022; see also8 W. N. Haworth, E. L. Hirst, and E. G. V. Percival, ibid., p. 2384 ; A., 11 17.2375; A., 1116.G . K.Hughes, A. K. Macbeth, and F. L. Winzor, ibid., p. 2026; A., 934128 OR,GANIC CHEMISTRY .-PART I.terminal unit in each case was estimated after cleavage of themethylated chain and glucosidation of the fragments as tetramethylmethylglucoside, and in the case of inulin as tetramethyl methyl-fructoside. The length of the chain and the corresponding molecularweights so determined are shown in the table.No. of C,-units. Mol. wt.Cellulose .................................... 100-200 20,000-40,000Starch (amylose) ........................ about 24 5,000Inulin ....................................... 30 5,000. , (am y lo pee tin ) .................. 9 ,Glycogen.. .................................. about 13 2,;ooThe value to be attached to these figures depends of course on theextent to which scission of the original polysaccharide chains hasbeen avoided in the preparation of the fully methylated product andthis consideration is of the utmost importance with a polysaccharideso susceptible of degradation as inulin.The production of fullymethylated polysaccharides, under conditions precluding degrada-tion, was studied prior to the above determinations and the poly-saccharide derivatives actually utilised were stated to be demon-strably free from scission products of small chain-length and to havebeen formed to all appearance without any degradation of theoriginal molecules. In this connexion it is to be remembered thatH. Staudinger and H. Freudenberger lo claim, on the basis ofviscosity measurements, that native cellulose is more complex thanthe most complex of the acetates.The values are, however, putforward as the average lower limits of the size of the macromolecules,and it is not regarded as impossiblle that the native celluloseshave molecular magnitudes of the order of the higher limit aboveindicated.A method analogous to the above, employing Willstatter andSchudel’s hypoiodite procedure for determining the free aldehydegroups of sugars, had previously been applied by different workersto determining the length of chain of the polysaccharides and theirderivatives. This method furnished evidence that cellulose can bebroken down by acetolysis to dextrins containing varying numbersof glucose units (e.g., 8-13, 3040, 20-60, etc.), but it proved tobe unreliable when applied to the more complex substances, includ-ing cellulose itself.ll H.Staudinger and H. Freudenberger place the9 For details, see the above cited papers. See also W. N. Haworth andH. R. L. Streight, HeZv. Chim. Acta, 1932,15,609 ; A., 724 ; W. E. Hagenbuch,ibid., p. 616; A., 725.lo Bey., 1930, 63, [B], 2331; A . , 1930, 1416.l1 Ann. Reports, 1930, 27, 112FARMER. 129limit of its reliability at chains of 60 glucose units,12 but its trust-worthiness up to even this degree of complexity is contested byK. Hess and his collaborators.13 For starch a chain-length of 25-30glucose units has been determined by its means-a value not differinggreatly from the foregoing estimate ; but for cellulose the correspond-ing value is one of only 50 units (average).llAnother purely chemical method which has been applied to thedetermination of the chain-length of celluloses from various sourcesrelies upon the estimation of the carboxyl content of the material : l4this is stated to be quite appreciable and to vary little with thesource of the cellulose.The length of the chain is in this wayassessed at 96 glucose units or a multiple thereof, whilst that of xylan,which is associated with the cellulose in wood, is similarly assesseda t 16 C,-units or a multiple thereof.Homogeneity of Structure.-In view of the structural relationshipwhich is held to exist between cellobiose and cellulose on the one handand between maltose and glycogen or starch on the other, the factthat very high yields of 2 : 3 : 6-trimethyl glucose are derivable fromthe methylated polysaccharides would seem to preclude the possi-bility that polysaccharide structures are other than homogeneouschains or large rings ; furthermore, the isolation of tetramethylglucopyranose suggests very strongly that each of the structures isan open chain of limited length. Nevertheless there are featuresconnected with the degradation products of the polysaccharideswhich are considered to throw grave doubt on the homogeneity ofthe molecular structures.Thus Sir J. C. Irvine maintains that whencellulose is methylated on a large scale and the product subjected tograded hydrolysis, only 2 : 3 : 6-trimethyl glucose is Liberated in thefirst instance, the 2 : 3 : 4 : 6-tetramethyl glucose being derived fromthe more resistant fractions of the methylated celldose.l5 Asimilar indication of non-homogeneity applies also to starch and toinulin, since it is stated in connexion with the former that one of thefractions of methylated amylose examined was convertible into amixture of sugars which contained as much as 23--26% of 2 ; 3 : 4 : 6-tetramethyl glucose together with 65--52% of 2 : 3 : 6-trimethylglucose, and 21% of 2 : 3- and 2 : 6-dimethyl glucose ; of the latterl2 Ber., 1930, 63, [B], 2331; A., 1930, 1416.13 K.Hess, K. Dziengel, and H. Maass, Ber., p. 1922; A,, 1930,1416; K. Dziengel, C. Trogus, and K. Hem, Annakn, 1931, 491, 52; A.,1932, 47.14 E. Schmidt, W. Simson, and R.Schnegg, Naturwiss., 1931,19, 1006; A.,1932, 149; E. Schmidt, K. Meinel, W. Jandebeur, W. Simon, and others,Celtulosechm., 1932, 18, 129; A., 934.15 Nature, 1932,129,470; Chem. and Ind., 1932,263; A., 502.REP.-VOL. XXIX. 130 OKGdNIC CKXEMISTRY .---PAl<T I.it is stated that a chain length of 25 or of 43 fructose units could bededuced according to whether the ~-methoxy-5-methylfurfural andtrimethyl anhydrofructose produced as by-products in the hydrolysiswere calculated as tetramethyl y-fructose (total 2.7%) or not (total1.7%).This question of the homogeneity of structure of wood and cottoncellulose as revealed by the composition of their hydrolysis productis considered a t some length by D. J. Be11.16 Two main considera-tions enter into the discussion : (1) the extent to which the hydro-lytic fission of directly methylated celluloses differs from that ofcelluloses which have been acetylated as a preliminary stage insecuring easy and complete methylation (the procedure employed byHaworth and Hirst and their collaborators) ; (2) the reason for theinertness towards hydrolytic reagents of certain resistant portionsof methylafed wood cellulose.Bell, like H. Staudinger and H.Freudenberger,ll considers that acetylation treatment-especiallyof the kind used in the production of acetone-soluble acetates-causes extensive depolymerisation of cellulose,17 so that the forma-tion of an appreciable amount of tetramethyl glucose from themethylation product of the so-called " depolymerised " celluloseand none from that of so-called " intact " cellulose is accounted for ;moreover, there is no necessity to assume that intact cellulosepossesses an open-chain structure, since ring fission of a closedsystem could occur by acetolysis where acetylation is employed as apreliminary to methylation.With regard to the resistant portionsof methylated wood cellulose, which are obtained both from " intact "cellulose and from celluIose which has been " depolymerised " by apreliminary acetylation process, hydrolysis is successful only afterthe material has been submitted to acetylation : then tri-, di-, andmono-methyl derivatives of glucose are formed and the conclusion isdrawn that the inertness of the methylated material towards hydro-lytic reagents is due to more fundamental reasons than degree ofpolymerisation, that is to say, presumably, to non-homogeneityof structure.I n connexion with the homogeneity of inulin it is to be noted thatthe very stable crystalline anhydrofructose derived by Sir J.C. Irvineand J. W. Stevenson l8 by the action of chloroformic nitric acid onl6 Biochem. J . , 1932, 26, 590, 598, 609; A., 934.17 E. Elod and A. Schrodt (2. angew. Chem., 1931,44,933; A., 1932,48) onthe contrary show by viscosity measurements that the conversion of primarycellulose acetates (insoluble in acetone) into secondary acetates (soluble inacetone) by means of acetic acid involves some deacetylation but no appreciablechange in molecular aggregation.18 J. Amer. Cliem.SOC., 1929, 51, 2197 ; A., 1929, 1046FARMER. 131inulin proves to be a clifructose anhydride doubtless possessing theformula : 89 l9HO*CI-I, KT/ \<"""oy/og O-CH, Yi: CH,.OHHO HH I i HO HThis substance, which was originally thought to represent in allprobability a heterogeneous component of the inulin chain, isobtainable not only by the action of nitric acid but (in the form of itsmethyl derivative) by the mild hydrolysis of methylated inulin ; itsresistance to hydrolysis, whereby it yields fructose, is probably to beattributed to the characteristic dioxan structure of the anhydridering. Three stereo-forms of the anhydride are theoretically capableof existence and three isomeric forms of difructose anhydride werereported last year, one of which proves t o be identical with Irvineand Stevenson's compound.The formation of the anhydrideappears to be brought about by rupture of the primary valencieswhich connect the fructose units in inulin and their reunion to formthe more stable compound; at any rate there is nothing in theevidence so far adduced to show that the anhydride is pre-formed ininulin or to conflict with the view that the inulin chain is homo-geneously composed of fructose units as represented in formulaThe most important evidence concerning the homogeneity orheterogeneity of structure of cellulose and starch must necessarilybe derived by detailed study of degradation. Here, however, thelines of investigation are manifold, embracing the kinetics ofhydrolysis, the range of possible cleavage products, and the correla-tion of rotational and X-ray data.Degradation of Gellalose and Starch.-Degradation of cellulose ormethylated cellulose to the di-, tri-, and tetra-ose stages has beendefinitely accomplished by acetolysis 2*) 21 and hydrolysis ; 22l9 E.W. Bodycote, W. N. Haworth, and C. S. Woolvin, J., 1932,2389; A.,1117; W. N. Haworth and H. R. L. Streight, Helv. Chim. Acta, 1932,15, 693;A., 724; H. H. Schlubach and H. Elsner, Ber., 1932,65, [B], 519; A,, 603. Thelast authors suggest a monofructose structure.2o K. Freudenberg, C. C. Andersen, Y. Go, K. Friedrich, and N. W. Richt-myer, Ber., 1930,63, [B], 1961; A., 1930, 1412; F. Klages, ibid., 1931,64, [B],1193; A., 1931, 827; W. N. Haworth, E. L.Hirst, and H. A. Thomas, J.,1931, 824; A., 1931, 941.a1 K. Freudenberg, K. Friedrich, and I. Bumann, Annabn, 1932, 494, 41 ;A., 501.22 L. Zechmeister and G. Toth, Ber., 1931, 84, [B], 854; A., 1931, 716.(XLV)132 ORGANIC CHEMISTRY.-PART I.degradation to the penta- and hexa-ose stages appears also to havebeen 21 Degradation to certain other of the simplerstages, as represented by celloisobiose, procellose, and the well-known“ biosan ” of K. Hess and H. Friese, has also been reported, but thereis now little doubt that the “ biosan ” is a cellodextrin or mixture ofcellodextrins of high molecular weight (at least 2000) and recentwork shows that celloisobiose and procellose represent one and thesame tri~accharide.~~ With regard, however, to the long series ofpolysaccharides which might be expected to range between hexaoseand undecomposed cellulose, the most elaborate fractionations ofdegradation products have failed to yield pure individuals.Thesize of the break-down products appears to be to some extentcontrollable by adjusting the conditions of acetolysis, but it isremarkable that, whereas W. N. Haworth and K. M a ~ h e m e r , ~ ~ likeH. Staudinger,26 K. FreudenbergY27 K. H. Meyer and H. Mark,28 andtheir respective collaborators, have found the cellodextrin acetatesderived by acetolysis to be separable into groups of different averagechain-length, K. Hess and his collaborators z9 have found that undercomparable conditions of acetolysis the product appears to be com-posed of a single crystalline variety of cellulose acetate (Hess’s celluloseacetate 11) and one or two of the early members of the cellodextrinseries.30 The impossibility of effecting the complete separation ofthe few components in the latter case is attributed to the formationof additive complexes between the latter.Haworth and Machemer’sresults for the methylated cellodextrins, which were achieved byestimating the amount of te t ramet h yl met hylglucoside obtainable oncomplete hydrolysis, differ little from those obtained directly for thecellodextrin acetates : the individual polysaccharides range in sizefrom chains of 11 to chains of 26 glucose units.From the acetolysis product of starch, maltotriose and malto-tetraose (in addition t o glucose and maltose) have been isolated inthe form of their fully-methylated derivatives. I n connexion with23 K.Hess and F. Klages, Annalen, 1932, 497, 234; A., 1022.24 W. N. Haworth, E. L. Hirst, and 0. Ant-Wuorinen, J., 1932, 2368; A . ,25 Ibid., p. 2372.2 6 Ber., 1930, 63, [B], 2313, 2331, 3132; A., 1930,’ 1415, 1416; 1931, 202;2 7 K. Freudenberg and E. Bruch, ibicl., 1930, 63, [B], 535; A., 1930, 457.1116.ibid., 1931, 64, [B], 1688, 1694; A., 1031, 1040.K. H. Meyer and H. Mark, ibid., 1928,61, [B], 2432; A., 1029, 51 ; K. H.Meyer, H. Hopff, and H. Mark, ibid., 1930, 63, [B], 1531; A., 1930, 1025.29 K. Dziengel, C. Trogus, and K. Hess, Annalen, 1931, 491, 5 2 ; A., 1932,47.30 These lower polysaccharides, including the bioses, trioses, tetraoses, etc.,derived from cellulose and starch, have been conveniently termed by K-Fre udenberg, ‘ ‘ oligosaccharides.’ FARMER. 133these substances and the corresponding oligosaccharides fromcellulose, K. Freudenberg and his collaborators 21 point out that ifthe molecular rotation, [MIn, of a polysaccharide of n units be repre-sented as the sum of the rotations due to the two (aldehydic and non-aldehydic) end units, [MI, and [MI,, respectively and to 72-2 inter-mediate units each furnishing a rotation-contribution of [MI, /a(this differing little from that due to the middle unit of a penta-saccharide), there is justification for writing the resulting expression,(n - 2)[M],/a, or, to show the average contribution of one unit ofthe chain, in the formW l n = “la + (m - 2)[M]m /a + [Mle, in the form [ J f b 8 = [MI, +The difficulty which attends the application of the expression to thecalculation of the rotation of the higher polysaccharides, owing tocomplication arising from the existence of a- and @-forms, is fullyrecognised ; the values calculated for the trioses and tetraoses byemploying the observed values for the relevant bioses and hesaosesare in good agreement with the experimental values obtained underequilibrium conditions in various solvents ; moreover, the value of0-3” calculated for cellulose in water is a credible one.The progress of the hydrolysis of cellulose with 50% sulphuricacid has been measured by titration with iodine, and from the resultsvalues for K , and K,, the hydrolysis constants concerned respectivelyin the initial rupture of the intact chain and in the final stage ofhydrolysis (cellobiose to glucose), have been cal~ulated.~l Now, ofall the possible assumptions that might be made in terms of theseconstants as to the course of hydrolysis of the cellulose molecule(e.g., that K , is the hydrolysis constant applicable to the fission of allglucosidic linkages present in the molecule of triose, tetraose and soon up to cellulose, and K, is the hydrolysis constant of cellobiose),it is shown, on the basis of certain calculations of W.Kuhn32 as tothe form of various alternative hydrolysis curves, that only two arereconcilable with the observed changes in the value of the velocityconstant as hydrolysis proceeds : of these two, only one is definitelysupported by independent values for the velocity constant obtainedby following the course of reaction polarimetrically.This assump-tion is that Kl represents the hydrolysis constant of the tetraose andall higher fragments up to cellulose, and K, the constant of cello-31 K. Freudenberg, W. Kuhn, W. Durr, F. Bolz, and G. Steinbrunn, Ber.,1930, 63, [B], 1510; .A., 1930, 1025; compare K. H. Meyer, H. Hopff, andH. Mark, {bid., 1929,62, [B], 1103; 1930,63, [B], 1531; A,, 1929, 799; 1930,1025.32 IbicE., p. 1503; A,, 1930, 1025134 ORGANIC CHEMISTRY.-PART T.biose and cellotriose. Obviously this represents only an approxima-tion to the truth, since if cellulose be conceived as a long chainmolecule a number of transition values must actually lie between thehydrolysis constant applicable to degradation of the long fragments(K,) and that concerned in the last step (K2).(Thus, although Kzis attributed to both the biose and the triose, the triose will possess alower mean constant than K,, and the tetraose and pentaose a higherconstant than Kl.) Nevertheless, provided Kuhn’s fundamentalexpressions are accepted,33 the experimental results afford strikingevidence as to the uniformity of the linkages throughout the cellulosechain.Starch behaves in the same manner as cellulose, but its constantsare higher and the difference between K , and K, is smaller than inthe case of cellulose.31 Owing to the latter fact distinction betweenthe long-chain formula and a biose anhydride formula for starchwould have been impossible without other evidence.In this con-nexion the fact that starch yields nearly 100% of maltose duringdiastatic hydrolysis appears a t first sight to be in opposition to theconception of the former as a chain of 1 : 4-linked a-glucose units;but this observation probably only means that the enzyme attacksone end of the chain in much the same way that the oxidation ofcellulose chains is held to occur.34Some interest attaches to the group of simple polysaccharideanhydrides derived from starch by the action of F. Schardinger’sbacilI~s,~5 although the formation of these has no clear bearing onthe constitution of starch. Two of the anhydrides originallyrecognised by H.Pringsheim 36 in Schardinger’s a-dextrin nowappear to be identical (the supposed diamylose is the same as thetetra-amylose) ;37 but more interesting is the fact that X-rayexamination of a-amylose (amylopectin) is stated to show theexistence of six distinct modifications which differ in X-ray patternand are capable of interconversion either in solution or during thetransformation of solvent -containing forms into solvent -free ones .3 8The nature of the molecular changes in starch and cellulose and their33 See the contention of F. Klages, Ber., 1932, 85, [B], 302; A., 370; see34 T. Nakashima, J . SOC. Chem. I n d . Japan, 1931, 34, 414; A., 1932, 149.35 Centr. Bakt. Par., 1911, ii, 29, 188; A , , 1911, i, 181.36 Ber., 1912, 45, 2533 and subsequent papers; A., 1912, i, 832; see alsoH.Pringsheim, A. Weidinger, and P. Ohlmeyer, ibid., 1931,64, [B], 2125; A.,1931, 1277.3 7 A. Miekeley, ibid., 1930, 64, [B], 1957; 1932,85, [B], 69; A., 1930, 1414;1932, 255; M. Ulmann, Biochem. Z., 1932, 251, 458; A., 1021; K. Hess andM. Ulmann, Naturwiss., 1932,20,296; A., 724. See, however, H. Pringsheim,9. Weidinger, andH. Sallentien, Ber., 1931, 84, [B], 2117; A., 1931, 1276.<38 M. Ulmann, C. Trogus, and I<. Hess, ibid., 1932, 65, [B], 682 ; A., 604.also the reply of K. Freudenberg and W. Kuhn, ibid., p. 484; A., 501FARMER. 135derivatives which are responsible for these modifications of theX-ray diagrams are at present obscure. The water-soluble oligo-saccharides (tetraose, pentaose, and hexaose) derived by acetolysisof cellulose are stated to give the same interferences as hydro-cellulose,39 whilst the native and mercerised forms of cellulose as wellas a number of modifications of starch are all reported to show quitedistinctive X-ray diagrams.40 It is suggested, indeed, that three orfour truly isomeric forms of cellulose and four or five such forms ofstarch exist, the isomerism being of a steric nature, due to thepliation of the pyranose rings.Cellulose, starch, inulin, mannan, xylan, silk fibroin, wool, horn,etc., are all reported to be broken down to mixtures of low-molecularanhydrides by the action of dry hydrogen chloride.41 It is suggestedthat addition compounds with the reagent are first formed, andthese, being more susceptible of degradation than the original com-pounds, yield small molecules (possibly unimolecular) whichsubsequently revert to a more or less highly polymerised condition.Degradation of cellulose acetate to the condition of a water-solublecarbohydrate has been effected by benzenesulphonic acid,42 and thatof starch to gentiobiose by heating with dilute hydrochloric acidunder pressure.43 In the latter case the disaccharide would appearto be a reversion product of glucose, but its formation by directscission of a polysaccharide in the cc-amylose portion of the starchis the view recorded.With respect to the amylose and amylopectin portions of starch,although the former is generally regarded as constituting the majorportion of the starch grain, it is now stated that the yields of amylo-pectin derived by the action of dilute methyl-alcoholic hydrogenchloride on different starches range from 63 to 83%.The amylo-pectin thus obtained, while probably not identical with the naturalsheath substance of the grains, is claimed to be (unlike formerpreparations) free from a m y l o ~ e . ~ ~Synthuis of Cellulose.-The action of bacteria in building upsubstances of polysacc haride character from sugar- cont ainingmaterials has long been observed. Now, however, it is shown thatthe membranous material produced by the action of Acetobacterxylinum on glucose behaves in all its observed physical and chemicsl30 K. Hess and F. Klages, Annalen, 1932,497,234; A., 1022.40 J. R. Katz and A. Weidinger, Rec.trav. chim., 1932, 51, 842; A,, 934.4 1 H. H. Schlubach, H. Elsner, and V. Prochovnick, Angew. Chem., 1932,45,42 H. Pringsheim and K. Ward, jun., Cellulosechem., 1932, 13, 6 5 ; A., 502.43 T. C, Taylor and D. Lifschitz, J. Arner. Chem. Soc., 1932, 54, 1054; A.,44 A, Eckert and A. Marzin, J. pr. Chem., 1932, [ii], 133, 110; A., 370,245 ; A., 502.500136 ORGANIC CHEMISTRY.-PART I T .properties (including rotation, X-ray structure, acetylation, methyl-at,ion, and hydrolysis) as a true cell~lose.~~E. H. FARMER.PART IT.-HOMOCYCLIC DIVISION.Ta.utomerism .(Continued from Ann. Reports, 1931, 28, 105.)Three-carbon Systems.-The work on the influence of structure ontautomerism in three-carbon systems terminated by one activatinggroup, of the general type(1.) >CH&CRX >C:d*CHRX (IT.)a,!?-form flyform(X = CO,H, CO,Et, CN, or COMe)is now reaching finality inasmuch as all the more accessible systemshave been examined, and it is of interest to review the results inthe light of the theoretical considerations advanced to explain them.The application of the electronic theory to this problem, origin-ally proposed by Ingold, Shoppee, and Thorpe and used in theseReports, was extended by R.P. Linstead,2 who pointed out thatthe influence of steric factors and the effect of conjugation (Lap-worth and Manske’s “ Thiele factor ”) 3 must be taken into accountin addition to the polar factor. The theory in that form gives asatisfactlory explanation of the interconversion of unsaturatedacids (I and 11; X = C02H) or, more strictly, their anions inalkali.*Thus, the introduction of an alkyl group in the a-position retardstautomeric change and causes a shift of the equilibrium towardsthe @-form; an allryl group introduced into the y-position causesa marked shift in the opposite direction without affecting themobility, that is, the rate a t which equilibrium is established; andan alkyl group in the P-position also favours the &-form. The45 H. Hibbert and J. Barsha, J . Amer. Chem. SOC., 1931,53, 3907 ; A., 1931,1401; Canadian J . Res., 1931, 5, 580; A., 1932, 256; E. Schmidt, 31. Atterer,and H. Schnegg, Cellulosechem., 1931, 12, 235 ; A., 1931, 1038.1 J., 1926, 1477; A., 1926, 939.J . , 1929, 2498; A., 1930, 64; compare Ann.Reports, 1931, loc. cit.J . , 1928, 2535; A , , 1928, 1245.* The statement that the interconversion of acids is studied “in sodiumethoxide a t 25” ” (Ann. Reports, 1931, 28, 108) should read “with 10 equiv-alents of 25% potassium hydroxide solution a t lOO”.” The footnote on thesame page refers to the cyuilibration of the ester, not the acid.-G. A. R. IconKON. 137principal discrepancy is the position of equilibrium in the cyclicacids, in which the &form is favoured in every case :85% By at equil.(111.)this will be discussed below.In nitriles (I and 11; X = CN) the equilibrium is largely in-fluenced by the great tendency of the cyano-group to become partof a conjugated system: this was again observed in a recentinvestigation.4 This conjugative effect accounts for the fact that,of all the unsaturated nitriles examined, only two are preferentiallystable in the py-form.These are isohexenonitrile (VI)4 andphenylcrotononitrile (VII) 5 : the former owes its stability to tlheWI.1 CMe,:CH*CH,*CN CHPh :CH CH,*CN (VII* 1polar effect of the y-alkyl group, and in the latter the phenyl groupexercises a strong conjugative influence opposed to that of thenitrile group.In nitriles, therefore, the effect of a p-alkyl group is negligible;but a y-group produces its normal effect, doubtless because it actsdirectly on one of the carbon atoms concerned in tautomerism.Unsaturated nitriles have also been the subject of repeated studyby Bruylants and his schoo1,G but mainly from the stereochemicalpoint of view.Bruylants criticises some ofLetch and Linstead's conclusions, more especially as regardsthe purity of the nitriles prepared by different processes and thevalue of the analytical methods employed by the two schools;these differences in no way affect the main conclusions discussedabove.*In unsaturated ketones (I and 11; X = COMe), although theeffect of 8- and y-substituents on tautomerism accords well withIn his latest paperR. A. Letch and R. P. Linstead, J., 1932, 443; A., 371.A. Kandiah and R. P. Linstead, J., 1929, 2139; A., 1929, 1294.P. Bruylants, Bull. SOC. chim. Belg., 1930, 39, 572; R. Breckpot, ibid.,p. 462; P. Colmant, ibid., p. 568; G. Heim, ibid., p. 458; A., 1931,472, 194,472, 205; P.Bruylants and H. Minetti, Bull. Acad. TOY. Belg., 1930, 16,1116; P. Bruylants, ibid., 1931, 17, 1008; P. Bruylants and L. Emould,ibid., p. 1027; A., 1931, 205, 1403; A. Dewael, Bull. SOC. chim. Belg., 1932,41, 318, 324; J. Baerts, ibid., p. 314; G. Festraete, ibid., p. 327; P. Bruy-lants, ibicl., p. 333; A., 1119.P. Bruylants, ibid., p. 309; A., 1119.* Dr. Linstead informs the Reporter that a re-examination of the nitrilesused in Let& and Linstead's work leaves no doubt as to their purity;Bruylants's criticism on this point appears to be based on a misunderstanding.E 138 ORGANIC CHEMISTRY .-PART 11.theory, that of an a-alkyl group, founded on numerous observationsJgcauses not only a great diminution of mobility but also a pronouncedshift in equilibrium towards the @form, that is, in the oppositesense to that predicted by theory.Moreover, rema,rkable differ-ences, not predictable from considerations of polarity, are observedbetween the different cyclic derivatives : 9TH2*CH2)C:CHX CH~(CH:.CH~ CH 'CH'2)C:CHX ~H2*CH2*CH2)C:CHX(X = COMe)CH2*CH2 CH2*CH2*CH277% up at equil. 23% aP 40% UPFinally, the equilibria in a representative series of unsaturatedesters have been examined; lo these follow in the main the ruleslaid down for acids, but ethyl CycEopentylideneacetate constitutesan exception to this, the equilibrium favouring the ap-compoundas in the corresponding ketone ; the compound is also exceptionallymobile, apparently a characteristic of all cyclopentane derivatives.The effect of the a-alkyl group is irregular, for it favours the&form in the cyclohexane derivative but in no other case.Ester (up-form).Equilibrium (yo up). Mobility.CHMe,.CH:CH*CO,Et * ............... 10 (?) HighCH,Et*CH:CH*CO,Et .................. 92 (?) 153CH,Et.CH:CMe.CO,Et .................. 95 151CMeEt:CH*CO,Et ........................ 75 26CMeEt:CMe*CO,Et ..................... 05 2CH,*CH,1 \C :CH *C 0 ,E t 60 835CH2*CH2/CH2\CH,CH,/CH2*CH2\CH2*CH2CH2\CH,*CH,/...............,CH2*CH2\C:CH*CO,Et -1 ...... 38 8.11 /C:CMe*CO,Et ............... 88 84,CH,*CH,\C:CMc.CO,E t ...... 5 0.15* Linstead, J . , 1929, 2498. 7 Kon and Linstead, J., 1929, 1269.It is difficult to account satisfactorily for these anomalies.An attempt was made to explain l1 the preferential existence ofcyclohexane derivatives in the py-form by assuming that the wander-8 G.A. R. Kon and E. Leton, J . , 1931, 3496; A., 1931, 1274; compares Ann. Reports, 1929, 26, 117. The figures given above are the latest10 G. A. R. Kon, R. P. Linstead, and G. W. G. Maclennan, J., 1932, 2454;11 S. F. Birch, G. A. R. Kon, and W. S. G. P. Norris, J., 1923, 123, 1361;Ann. Reports, 1931, 28, 109.available; Kon, J., 1930, 1616; A., 1930, 1184.A., 1111.G. A. R. Kon and E. A. Speight, J . , 1926, 2727; A., 1926, 1246KON. 139ing of the double bond into the ring relieves the strain in the six-membered ring which is postulated by Baeyer's strain theory.Conversely, it has been suggested by Bennett (Ann.Reports, 1929,26, 118) that the greater stability of the ap-form in cyclopentanederivatives is due to the fact that the migration of the double bondinto the five-membered ring introduces a strain : a particularlygood example of this difference is afforded by the substitutedmalonic acids (VIII) and (IX) ; the former exists exclusively in theap- and the latter in the @-form and their respective isomeridesdo not appear to be capable of isolation.12 *The equilibria in the monocarboxylic acids (111), (IV), and (V),however, cannot be reconciled with these views. In addition, thefoundation for them has been considerably weakened by theobservations of R. S. Thakur 13 on a number of dicyclic acids,ketones, and esters of the type (X) and (XI).He finds thatCH, CH,/\ /\\/\/QH, QH QXRXCH, CH CH2CH, CH,CH, CH,/ \ /\\/\/QH, QH GCHRXCH, CH CHCH, CH,p-decalin derivatives behave in all respects like the correspondingcyclohexane compounds, the figures in the two series agreeing withina few units yo :X = C0,H : R = H, 88% By at equil.; R = Me, -yo By at equil.X = COMe : R = H, 63% By at equil. ; R = Me, 100 yo By at equil.X = COzEt : R = H, 60% By at equil. ; R = Me, 90% By at equil.The anomalous effect of the or-alkyl group is again observed.In the corresponding tram-hexahydrohydrindene derivatives ofthe general type (XII) and (XIII), Thakur l4 k d s that the equili-brium is in every case, including the monocarboxylic acids, on thel2 W. E. Hugh and G. A. R. Kon, J., 1930, 775; A., 1930, 1162.l3 J., 1932, 2129, 2139; A., 1032.l4 Xbid., pp.2147, 2157; A., 1032.* The statement (Ann. Reports, 1931, 28, 110) that the ester of the acid(VIII), when regenerated from its sodio-derivative, contains 30-50y0 of theBy-isomeride is erroneous. The original authors did not give an estimate ofits By-content, but the ester appeared from its physical properties to bepractically pure ethyl cyclopentenylmalonate; this view is c o h e d byunpublished experiments140 ORGANIC CHEMISTRY.-PART II.side of the ap-form; the compounds display even greater mobilitythan cyclopentane derivatives.With regard to the decalin derivatives, the results may be summedup by saying that the effect of the cyclohexane ring remains the samceven when the ring becomes part of the dicyclic system.The strainless nature of the decalin system is now generallyaccepted, although there is not the same measure of agreementregarding the simple cyclohexane ring.If the latter is strainless,no difficulty arises in the interpretation of the striking similaritybetween cyclohexane and decalin derivatives, but this means that the“ strain factor ” originally postulated has no existence. If, on t’heother hand, the single ring is regarded as strained, it must be inferredthat this strain has no influence on tautomerism, unless it be assumedthat the decalin system is strained to the same extent. It appearspreferable, therefore, t o abandon for the present all attempts tocorrelate ring strain with tautomerism.A similar argument applies to the cycEopentane and hexahydro-hydrindene compounds.The ring system of the former is strainlessand should not, therefore, differ in a radical manner in its influenceon tautomerism from the decalin system. The resemblance betweencyclopentane and hexahydrohydrindene compounds is not un-expected; the ring system of the latter appears from models t o beslightly strained (in the trans-form), but this strain is in the oppositcsense to that in the planar six-membered ring. The great tendencyof these compounds to exist in the ap-form might therefore be heldto support Bennett’s view (see above), since the entrance of the doublebond into the ring would tend to produce an even more strainedcondition than that present in cyczopentenyl derivatives, just as thefacts require.The Glutaconic Acids.-Some progress has been made in thcinvestigation of three-carbon systems terminated by activatinggroups at both ends of the general typeXCHR*CR‘:CR”X and X*CR:CR‘*CHR”X(X may be CO,H, CO,Et, or CN; R, R’ and R” may be dkyl or aryl groups,CO,H, or C0,Et)A brief reference to the subject has already been made in theReport for 1931, p.111; further investigations published in thKON. 141course of the year serve to establish several generalisations regardingthe simpler glutaconic acid~.l~-~O An unsymmetrically substitutedglutaconic acid, such as a-benzylglutaconic acid, can theoreticallyexist in two isomeric forms (I) and (11), each of which can giverise to two stereoisomerides :CO,H*C(CH,Ph):CH*CH,*CO,H CO,H*CH(CH,Ph)*CH:CH*CO,HIn practice two forms are usually encountered, namely, the cis-formof the ap-acid and the trans-form of the py-acid, the remaining twoisomerides being comparatively unstable ; Kon and Watson l8have, however, converted the cis-ap-form of a-benzyl- p-methyl-glutaconic acid into its trans-stereoisomeride by ultravioletirradiation.The relative stabilities of the two more stable modifications varywidely according t o the nature of the substituents present; e.g.,a-benzylglutaconic acid is stable in its trans-py-form, and the cis-ap-form is converted into this even on treatment with warm waterand therefore represents a true " labile " rnod&ation.l* The sameis probably true of other simple a-substituted acids; the cis-formof glutaconic acid itself has only lately been obtained 21 and is alsoextremely unstable.The a-benzyl- p-methyl acids (111) and (IV)are both stable, but the cis-acid passes integrally into its isomerideon treatment with alkali, and the reverse change is brought aboutby acids ; we therefore have one alkali-stable and one acid-stableform : 1,CO,H*C( CH,Ph) :CMe*CH,*CO,H e(I.) up-Acid (cis and trans) (11.) Py-Acid (cis and trans)alkali(111.) cis (ap) acidCO,H*CH( CH,Ph)*CMe:CH*CO,HThese acids thus differ from the majority of tautomeric compoundsin which the equilibrium is independent of the reagent employedand incidentally provide an interesting example of the conversionof a trans- into a cis-acid by the agency of hydrochloric acid, areagent commonly used t o bring about the reverse change.Similar relationships obtain in the p-phenyl- a-met hylglut aconicacids; l9 the presence of a phenyl group exercises the expected(IV.) trans (py)l5 G.A. R. Kon and E. M. Watson, J., 1932, 1 ; A., 252.l6 B. S. Gidvani, G. A. R. Kon, and C. R. Wright, ibid., p. 1027; A . , 601.1 7 G. A. R. Kon and H. R. Nanji, ibid., p. 2426; A., 1127.18 G. A. R. Kon and E. M. Watson, ibid., p. 2434; A., 1127.10 B. S. Gidvani and G. A. R. KOR, ibid., p. 2443; A., 1127.Z o G. A. R. Icon and H. R. Nmji, ibid., p. 2557; A., 1247.21 I. R. Malachowski, Ber., 1929, 62, [B], 1323; A., 1929, 794142 ORUANIC CHEMISTRY.-PART 11.stabilising influence (owing to its & T effect) on both possible forms(V) and (VI) : this is exemplified by the isolation, though in smallCO,HGMe:CPh*CH,GO,H CO,H*CHMeCPh:CH*CO,Hamount, of a third acid which appears to be the &-modificationThe stability of the different forms of unsymmetrically sub-stituted acids appears t o depend largely on steric factors in additiont o the expected polar effects and it has been suggested l8 that thesymmetrical distribution of groups about the doubly-bound carbonatoms is the principal one, thus :CH2Ph$*C02H CO,H*CH(CH,Ph)*EMe CO,H*CH(CH,Ph)*GMeCO,H*CH,*CMe HC*CO,H CO,H*CHStable StabIe Unstable(V.)of (VI).An investigation of some cyclic glutaconic derivatives showsthat ability to exist in stereoisomeric forms is not essential t o“glutaconic character.” The acid (VII) is just lilre an ordinary&substituted glutaconic acid ; it forms an enolic anhydride (VIII),its ester yields a stable potassio-derivative, and the latter can beconverted into the a-methyl ester (IX).These properties are there-fore solely connected with the existence of a mobile hydrogen atom.The acid (VII) and its ester and also the analogous cyclopentanederivatives only exist in one form, no sign of the expected isomerideswith the double bond outside the ring, such as (X), having beenencountered.CH2 CO/\/\\/\//QH2 $ ? (VIII.) Y?Y?(VII.) QH2 G*CO2HCH, C*CH2*C0,H CH, C C*OHCH, CH \/CH, P? 7H2 (IIHCO2H (X*) (IX.) YH, fi*CO,EtCH, C*CHMe*C02Et CH, C:CH*CO,H\ /CH2\/CH,A similar behaviour might have been ant,icipated in the acid (XI)and its ester, in which all three carbon atoms of the three-carbonchain are included in the ring :(XI.) CMe<CH*co2RC*CO,RSome of the reactions of these substances were indeed originallKON.143held to support such a view, although the " normal '' formulation(XII) was adopted for the acid and its solid ester.22A reinvestigation of the whole subject has led to some unexpectedconclusions.23 The ester, which is correctly represented by (XI),does not possess a mobile hydrogen atom in the ordinary senseand the supposed formation of a sodio-derivative cannot be sub-stantiated. The action of sodium ethoxide on this ester causesthe rapid addition of ethyl alcohol to the double bond to give theethoxy-ester (XIII) and no evidence has been obtained of theexistence of the Al-isomeride (XIV) of the ester (XI).The mostremarkable fact ascertained relates to the action of heat on theester (XI), which was stated to give rise to the " labile " modific-ation, formulated as (XI) by the earlier workers. This has now beenshown to consist of the straight-chain acetylenic ester (XV), thechange involving not only the opening of the cyclopropane ringbut the absorption of the methyl group into the chain.The behaviour of the ester (XI) with sodium ethoxide recalls thereaction of the esters of itaconic, citraconic, and mesaconic acids,which all undergo conversion into the same ethoxy-ester, directlyderived from itaconic ester : 24GH2 $?H,*OEt YH3$*CO,Et =+ Q*CO,Et -+ yH*CO,EtCH*C02Et CH,* C 0,E t CH,*CO,Et(cis and trans) Itaconic ester w-EthoxymethylsuccinicesterIt has, however, been shown that an equilibrium mixture of allthree unsaturated esters is produced and that the two stereoisomerica@-esters (citraconic and mesaconic) predominate in this; it isclearly unsafe t o conclude that the equilibrium in this case favoursthe &form (ethyl itaconate) because derivatives of the latter, suchas the ethoxy-ester and' the addition product with ethyl sodio-malonate, are preferentially produced,25 for additions are known tobe influenced by such factors as the solubility of the sodio-derivativesformed.The carbethoxyglutaconic esters l6 are generally similar to the22 F.R. Goss, C. K. Ingold, and J. F. Thorpe, J., 1923, 123, 327, 3342;25 G. A. R. Kon and H. R. Nanji, J . , 1932, 2557; A., 1247.24 E. H. Coulson and G. A. R. Kon, J., 1932, 2568; A., 1234.25 C. W. Shoppee, J., 1930, 968; A., 1930, 912.1924,125, 1927; 1925, 127, 460144 ORGANIC CHEMISTRY.-PART 11.corresponding cyanoglutaconic esters 26 in occurring as mixtures ofap- and py-isomerides,( C0,13t),C:CR*CHR'*C02Et (CO,Et),CH*CR:CR'*CO,Et(4) ( B Y )from which the py-forms can usuaIly be obtained in the pure stateby conversion into the potassium derivatives (which always havethe &structure ; no abnormal cases have been encountered) andacidification with a weak acid in the absence of water.* Ethyltx-carbethoxy-p-phenylglutaconate gives rise t o two different,metallic derivatives : 16? l9 the yellow, sparingly soluble sodio-derivative obtained in the condensation of ethyl sodiomalonatewith ethyl phenylpropiolate appears t o have the structure (XVI) ,whereas that formed from the ester itself on treatment with sodiuniethoxide has the sodium attached to the other end of the chain(XVII).A compound similar to (XVI) is also formed from ethyl(CO,Et),C*CPh*CH*CO,Et)Na Na((CO,Et),C*CPh*CH*CO,Et(XVI.) (XVII.)sodiomethylmalonate and ethyl phenylpropiolate, a fact which shouldhave a considerable bearing on the mechanism of the Michaelreaction, since it can be proved that in this case it is the sodiuniand not the methyl group of the addendum which separates andbecomes attached to the negatively polarised end of the unsaturatedmolecule.The cyanoaconitic esters26n arc difficult to purify imd do not lenrlthemselves to detailed study ; in general, however, they behave lilrothe cyanoglutaconic esters, particularly in forming abnormaly-alkyl derivatives : 26(XVIII.C0,Et *CH( CN)*C( CO,E~):CH~CO,E t -+(XIX.)The sodio-derivative of ths ester (XVIII) must also be derived fromthe isomeric ap-ester, and a product consisting mainly of the latteris obtained on acidification.26 G. A. R. Kon and H. It. Nanji, J., 1931, 560; A , , 1931, 608; compare2 b R. D. Desai, J . , 1932, 1088; A . , 602.* The repeated observation of such " false equilibria " lends strong supportt o the view that the anionic charge originally localised on one or other endof the three-carbon system (in the sodio-derivative) need not necessarily beredistributed and therefore lead to an equilibrium mixture when the mobilehydrogen atom is reintroduced by acidification.This redistribution appearsto take place under the influence of the acid (or water) and is analogous tothe phenomenon discussed on p. 146, namely, the selective reaction of benzyl-magnesium chloride to give a- or y-reaction products according to the reactantemployed.CO,Et*C( CN) :C( C0,Et )*CHR*CO,EtAnn. Reports, 1931, 28, 111RON. 145Methyleneamethine Xystems.-The effect of different meta-substituents on the mobility 27 in the systemx.2 R*C,H,*CR:N*CH,Ph s R*C,H,*CH2*N:CHPhx.2follows the order of the dipole moment of the compound R-Ph moreclosely than was the case with the corresponding para-compoundsY28in agreement with theoretical considerations. Similarly, the agree-ment between the effect on mobility and side-chain reactivity iscloser in the meta- than in the para-series.The effect of differentgroups on equilibrium should follow their effect in facilitatingmeta-substitution, but as all the groups employed (except NO,) areop-directing, a comparison is impossible and their effect on side-chainreactivity is theref ore employed.Annionotropy.-Comparatively little work has been carried out onthis subject. A. Kirrmann and R. Rambaud29 have found thatacetylation of the ester (I) with acetic anhydride leads to the corre-sponding acetate (11), but if the hydroxy-compound is treated withphosphorus tribromide, the bromine enters the y-, not the a-position ;the bromide (111) on treatment with sodium acetate gives an acetate(IV), isomeric with (11).(1.) CH,:CH*CH( OH)*CO,Et CH,:CH*CH(OAc)*CO,Et (11.)(In.) CH,Br*CH:CH*CO,Et CH2( OAc)*CK:CH*CO,Et (IV.)R.Rambaud 30 subsequently found that the ct-bromide isomericwith (111) was also produced but passed into (111) on distillation.The corresponding methyl ester undergoes the change even morereadily, but the a-chloro-ester can be prepared in the pure state andis stable ; on treatment with calcium bromide, however, the y-bromidealone is produced.Some abnormal cases of the Grignard reaction have been inter-preted on the assumption of an anionotropic mechanism.Cinnamylchloride (V) gives a magnesium derivative which is converted bycarbon dioxide into the acid (VI),31 and this is explained by themigration of the MgCl residue from the y- to the a-carbon atom :(V.) CHPh:CH*CH,Cl+ [CHPh:CH*CH,- -CHPh*CH:CH,](m.) CHPh(CO,H)*CH:CH, ---+ CPh(C0,H):CHMe (VII.)+ MgC1-2 7 C. W. Shoppee, J., 1932, 696; A., 384.28 Idem, J., 1930, 968; 1931, 1225; A., 1930, 912; 1931, 834; Ann.Reports, 1931, 28, 106.2s Compt. rend., 1932, 194, 1168; A., 600.30 Ibid., 195, 389; A., 930.31 H. Gilman and S. A. Harris, J . Amer. Chem. SOC., 1931, 53, 3641; A . ,1931, 1290146 ORGANIC CHEMISTRY .-PA4RT 11.The acid (VI) readily undergoes further change with acids or alkalis,or merely on heating, into methylatropic acid (VII), this time by aprototropic mechanism.The formation of the intermediate ionsor free radicals accords well with the isolation of as-diphenyl-AQc-hexadiene32 as a by-product in the above reaction, since thiscan result from the union of the two different radicals.The reaction of benzylmagnesium chloride with formaldehyde,giving o-tolylcarbinol, is interpreted on similar lines,33 the three-carbon system here involving the phenyl group :The two forms me probably in equilibrium, because the action ofcarbon dioxide on the Grignard reagent gives the normal product.phenylacetic acid.A somewhat similar explanation is advanced by P. R. Austin andJ. R. Johnson,34 who find that the course of the reaction is dependenton the nature of the compound reacting with the Grignard reagent ;for instance, o-tolyl derivatives tend to be produced from acidchlorides, anhydrides, formaldehyde, and its derivatives ; it issuggested that these influence the production of one or other electro-meric form of the benzyl radical, which then reacts.The tautomericchange can involve the p-position of the benzyl group if both o-posi-tions are substituted, leading to a&-migration of the MgCl group;thus the Grignard reagent from 2 : 6-dichlorobenzyl chloride giveswith acetyl chloride 3 : 5-dichloro-4-methylacetophenone (VIII),although with carbon dioxide the normal product, 2 : 6-dichloro-phenylacetic acid (IX), is obtained :&*llgC1 ()BF*co2H(VIII.)The migration of a PhSO, ion is held by D. T. Gibson 35 to explainthe production of the compound (XI) from benzenesulphonylacetone(X) and methyl p-toluenethiolsulphonate : 36(X.) Ph*SO,*CH,*COMe + C6H4Me*S0,*SMe ---+C6H4Me'S0,'CH(SMe)*COMe (XI.)and the compound (XI) can be converted into the correspondingbenzenesulphonyl derivative by means of methyl benzenethiol-32 H.Gilman and S. A. Harris, J . Amer. Chern. SOC., 1932,54, 2072; A,, 730.33 H. Gilman and J. E. Kirby, ibid., p. 348; A., 410.34 Ibid., p. 647; A., 385. 35 J., 1932, 1819; A . , 837.36 I d e m , J., 1931, 2641; A . , 1931, 1394KON. 147sulphonate in excess; the excess of PhSO, or C,H,Me*SO, ionsdetermines the course of the reaction, but the presence of the SMegroup is shown to be essential for the exchange to occur. The thiolgroups are also readily exchanged, such as SMe for SEt, in compoundsof the type (XI).The exchange of groups here is essentially inter-molecular and differs in this respect from the majority of tautomericchanges in which the separation of the mobile group is generallyinferred rather than proved.Further cases of tautomerism are discussed on pp. 173, 174.Other Rearrangements.-Owing to limitation of space the dis-cussion is deferred of a number of interesting papers on thepinacol-pinacolin change,3’ on pinacolinic dearninati~n,~~ and onthe rearrangement of quaternary ammonium salts 39 and ofo- hydroxy- and o-amino-arylsulphones .40A remarkable example of group migration is provided by triphenyl-methyl o-tolyl ether,41 the displaced group entering the side chain :The constitution of the product has been confirmed by G.S. Parsonsand C. W. Porter.42Terpenes.Progress in this group of natural products continues, especially inthe elucidation of the structure of the more complex compounds ofthe sesqui- and di-terpene group; the ,new investigations bearremarkable testimony to the usefulness of the so-called “ isoprenehypothesis,” which has frequently led t o the prediction of thecorrect structure when the experimental evidence was indecisive.In the monoterpene group few major problems remain to besolved, and of these the ever-green question of camphene has latelyundergone some notable developments.S. Nametkin and L. Briissoff 43 have found that a-methylcamphene(11), obtained by the dehydration of tert.-methylfenchyl alcohol (I)37 M.Tiffeneau, J. L6vy, and collaborators, Bull. SOC. chim., 1931, [iv], 49,1595 et seq.; W. E. Bachmann and F. H. Moser, J . Amer. Chem. SOC., 1932,54,1124; A., 515; W. E. Bachmann, ibid., p p . 1969,2112; A., 745,737; C.H.Beale and H. H. Hatt, ibid., p . 2405; A., 854.38 A. McKenzie and J. R. Myles, Ber., 1932, 65, [B], 209; A., 382; A.McKenzie and (Miss) E. M. Luis, ibid., p. 794; A., 746.39 T. Thomson and T. S. Stevens, J., 1932, 55; A., 262; J . L. Dunn andT. S. Stevens, ibid., p. 1926; A., 816.4O L. A. Warren and S. Smiles, ibid., pp. 1040, 2774; A., 735; A. A. Leviand S. Smiles, ibid., p. 1488; A., 735.4 1 P. Schorigin, Ber., 1926, 59, [B], 2506; A., 1927, 54.42 J. Amer. Chem. SOC., 1932, 54, 363; A., 267.43 Annalen, 1927, 459, 144; A ., 2928, 182148 ORGANIC CHEMISTRY .--PART TT.or of tert.-methylborneol,44 is hydrated to a methylisoborneol whichis not the 6-methyl compound (111) that should be formed by theusual Wagner mechanism, but the isomeric 4-methyl compound(IV) ; it gives on dehydration, in addition to a-methylcamphene, theisomeric p-methylcamphene (V), and this is readily reconverted into4-methylisoborneol :(1.1 (11.) (111.)H2C( l4 ‘CMe, EaOH&!Y,AH/”:”. -Ha0 H2C\ I ,CH*OHThe structure of the new products is definitely established andhas been independently confirmed by later work; 45 and a similarseries of reactions has also been carried out starting with tert.-p henylbornyl alc o hoL4These facts cannot be explained by the usual (Wagner) mechanismof the camphene change and the explanation advanced is that, justas dehydration of 2 : 2-dimet hylcyclohexanol can take place withoutchange of ring structure but is then accompanied by the wanderingof a methyl group (Meerwein),(V.) CHz2 ! 7 H2(f/7Me\CH2 (IV.)CMe\CMe, I -ACMeIsomer-withoutpinacolic I 4---H,C- Me2C//’CH,I13ina,coliccl1nngc%GZ+isomer-isat ionCH,rileso the reverse process also can take place; in this way a-methyl-camphene is hydrated as follows,CH*OH44 L.Ruzicka, Helw. Chim. Acta, 1018, 1, 110; A., 1915, i, 398; S. Namct-kin and M. Schlesinger, J. R ~ s s . Phys. Chem. SOC., 1919, 51, 144.45 M. Bredt-Savelsberg and J. Buchkremor, Ber., 1931, 64, 600; A., 1931,625; S.Nametkin and L. Brussoff, J. pr. Chem., 1932, 135, 165.46 S. Nametkin, A. Kitschkin, and D. Knrssanoff, J. p r . Chem., 1930, 124,144; A., 1930, 216RON. 149the camphene hydrate then passing into the more stable methyl-isoborneol.Now in the hydration of P-methylcamphene this pinacolic changedoes not take place ; owing to the fact that in this compound a CHgroup is present next to the CXH, group, the intermediate camphenehydrate (VI) can be formed by the simple addition of water tothe double bond :W e ) (VI.) (IV.) CH:OHThis simplified mechanism cannot apply to a-methylcamphene,because it would lead to an unstable tertiary alcohol; the primaryaddition product first undergoes a pinacolic change without iso-merisation of the ring, followed by the conversion of the p-methyl-camphene hydrate into 4-methylisoborneol.The dehydration of the latter yields, as already stated, mainly@-methylcamphene formed by the simplified process ; some cc-methyl-camphene is, however, produced at the same time, evidently by areversal of the sequence of changes just described, thus confirmingthe reality of both reaction mechanisms.When these considerations are applied to camphene itself, it isclear that both processes must lead to the same final product;thus, the dehydration of isoborneol must give rise to camphene :I Or i CHH 2 d c H b M e 2 H,C/ I \CMe2H,C-- I b e H,G,dH,C:CH2I CH2 I/\ CH'-OH -,isoBorneol CampheneThere are, however, implications in these changes which appear tohave escaped the original authors, and these have since been pointedFor instance, the two formulae of camphene given above are47 J.Houben end E. Pfankuch, Annulen, 1931, 489, 193; A., 1931, 1300150 ORGANIC CHEMISTRY.-PART II.not identical but represent mirror images (owing to the two rings notbeing in the same plane). Moreover, different products will beformed according as the methyl and the hydroxyl group which areinterchanged are cis or trans to one another. In the former casethere will be a reversal of the sign of rotation; in the latter, thetrans-isomeride will be formed, having the same sign of rotation asthe initial material :c CrM" Mec----Me /OH I /OHC---Mec----OH I /Meboth the products belong to the opposite optical system from thatof the initial material.Owing to the symmetrical nature of thebridge heads in camphene these changes involve a change not ofstructure but merely of optical properties; thus, in the reversibleconversion of camphene through the hydrochloride into isobornylchloride, the two forms corresponding to (a) and (b) would be inequilibrium and equal quantities of d- and Z-product should beformed, leading to complete racemisation, which is actually observed.The same process accounts for the racemisation of isobornyl chloridein boiling cresol. A similar mechanism explains the production 48of active camphene from bornyl chloride and aniline under mildconditions, whereas the inactive hydrocarbon is formed under moredrastic conditions.When one of the bridge heads in camphene or its derivativescarries a substituent, the Nametkin change leads to isomerisationas in the case of methylcamphene, as well as to optical inversion :this has been well illustrated by Houben and Pfankuch4' by stnumber of examples.For instance, Z-camphorcarboxylic acid wasprepared from d-camphor, its amide (VII) converted into theamine, and the latter into 4-hyiiroxycamphor (VIII) :Y 70-NH, NH2d f k H 2 H 2 d I CH,CMe2IH2+CH2 H,H.c\dna,/co "2QMi 0 \&jyfOI CMe21 + I CMe2h --+(VII.) (VIII.)48 P. Lipp and G. Stutzinger, Ber., 1932, 65, [B], 241; A., 398EON. 151From the latter the amide of 4-hydroxycamphenecarboxylic acid(IX) was obtained, which on hydrolysis with hydrochloric acidunderwent addition of water, the product suffering the Nametkinchange at the same time, and Snally forming camphorcarboxylicacid (XI) itself. The complete cycle thus involves the conversion ofthe Z- into the d-acid :CO*NH2 CO,H(IX.) (X.) (XI.)In a later paper 49 the conversion of d-camphor into its antipodeis described (via camphor dichloride, 4-chloroisoborneol, 4-chloro-camphor, and the reduction of the semicarbazone of the latter) :this supplies a proof of the reaction mechanism proposed byNametkin, not depending on racemisation phenomena.In connexion with camphor chemistry, the preparation ofd-B-homocamphor by the following series of reactions should benoted :C02H C0,Me C02Mec8H14<82 -+ <CHO <CHO -+ <C(OH)CH2-C02Et +-cGH:CH*C02H <CH2*CH2*C02H Gg>cH2 2C0,H C02HThe strongly dextrorotatory B-homocamphor was then convertedinto p-camphor 51 (epicamphor), which was la3vorotatory :An interesting experiment from the point of view of the " isoprenehypothesis " is that of T.Wagner-Ja~regg,~, who treated isoprenewith acetic acid containing a little sulphuric acid. Amongst thecondensation products were geraniol, cycbgeraniol, halo01 anda-terpineol, 1 : 4- and 1 : 8-cineole, and a monocyclic sesquiterpenehydrocarbon with three double bonds, convertible by formic acidinto a dicyclic one of the caryophyllene group.49 J. Houben and E. Pfankuch, Ber., 1931, 64, [B], 2719; A., 1932, 62.so F. Salmon-Legagneur, Compt. rend., 1931, 192, 748; A., 1931, 626.5 1 Idem, ibid., 1932, 194, 467; A., 399.6 2 Anncxkn, 1932, 496, 6 2 ; A,, 866152 ORGANIC CHEMISTRY.'-PART 11.The original hypothesis was that 1 : 4-dimerisation of isopreneresidues would take place, followed by hydration, and the formationof geraniol seems t o support such a view.In acid solution, however,linalool is known to give geraniol, and this process may accountfor its formation thus :8esquiterpenes.-The notable progress in this group is principallydue to the researches of L. Ruzicka, who has attacked the problemin a broad and fundament,al manner. In order to place beyonddoubt the identity of some of the naphthalene derivatives obtainedby the dehydrogenation of polyterpenes, he has synthesised all thepossible trimethylnaphthalenes ; 53 t,he synt,hesis of some importantphenanthrene derivatives, including pimanthrene and retene,was, however, carried out by R.D. Haworth, B. M. Letsky,and C. R. Mavin,54 and L. Ruzicka and H. Waldmann 55 haveindependently synthesised pimanthrenequinone. An interestingsynthesis of phenanthrenes is also due to 5. C . Bardhan and S. C.S e n g ~ p t a , ~ ~ who have obtained pimanthrene, retene, and 1 : 4-di-methylphenanthrene.For comparison with naturally occurring hydronaphthalenederivatives, decalin and all the possible methyldecalins have beenprepared 57 by a method which is an extension of that originallyused 58 for the preparation of decalin-1 : 3-dione :co co ' co5 3 L. Ruzicka and H. Ehmann, HeEv. Chirn. Acta, 1932, 15, 140; A., 277.5 4 J., 1932, 1784, 2720; R.D. Haworth, ibid., p. 1125; R. 1). Haworthand F. M. Bolam, ih;tl., p. 3248; A., 839, 608, 1024.55 Helv. Chiiii. Acta, 1932, 15, 907; A., 948.5 6 J., 1932, 2520, 2798; A., 1241.5 7 L. Ruzicka, D. R. Koolhaas, and A. H. Wind, H e h . Clii?n. Acta, 1931,58 G. A. R. Kon and M. Qudrat-i-Khuda, J . , 1926, 3071 ; A . , 1927, 150.14, 1151, 1171; A., 1931, 1302RON. 153The diketone undergoes reduction by Clemmensen’s method t o thesaturated hydrocarbon, which is found t o belong t o the truns-series-another illust,ration of the remarkable ease with which thetruns-locking of the second ring occurs.‘A comparison of the physical properties of the dicyclic sesqui-terpenes and their fully saturated reduction products with thesynthetic decalins shows that the former all belong to the cis-series.Bisabolol and bisabolene trihydrochloride have been synthesisedas follows : b9 B-terpineol was ozonised, giving the ketone (I), whichwas condensed with the Grignard reagent from z-bromo- p-methyl-Ap-pentene, giving hisabolol (11), converted into a trihydrochlorideidentical with that prepared from nerolidol :\C:CMe2(1.) (11.)This synthesis removes all doubt as to the position of the doublebonds, which formerly rested on analogy.The structure of eudesmol may now be considered as settled.60The formula (111) was regarded as probable,61 although the alt’erna-t,ive (IV) had not been finally disposed of :Me MeHO II(IV. 1CH,IICH2MeH(111.) Mea-form /3-formA hydroxyl group attached to a side chain is much more readilybenzoylated than one directly connected t o the ring; 62 it is nowfound that eudesmol readily gives a benzoyl derivative. Ifeudesmol is correctly represented by formula (111), the dihydro-chlorides of eudesmenc and of selinene should be identical or, atmost, stereoisomeric, and this has now been confirmed; the di-hydrochloride of selinene exists in two stereoisomeric forms, m.p.52” and 74”, respectively. The final proof of the position of thehydroxyl in eudesmol was obtained by dehydrating dihydroeudesmol59 L. Ruzicka and M. Liguori, Helu. Chim. Acta, 1932, 15, 3 ; A., 277.6o L. Ruzicka, A. H. Wind, and D. R. Koolhaas, ibid., 1931, 14, 1132;A., 1931, 1302.L. Ruzicka and E.Capato, Annalen, 1927, 453, 62 ; A . , 1987, 570.E2 L. Ruzicka and A. G. van Veen, ibid., 1929, 476, 109; A., 1929, 1305154 ORGANIC CHEMISTRY .-PART TT.under very mild conditions; the hydrocarbon (V) was then almostexclusively produced, and gave acetyldimethyldecalin (VI) onozonisation :CH20(v.) Me (vI.) MeThe formation of the isopropylidene analogue of (V), previouslyobserved,61 was inconclusive, since this could have been formedfrom an eudesmol of the structure (111) or (IV).Eudesmol, however, is a mixture of a- and @-forms, for oxidationproducts of both have been obtained from it :a-form1Me *n - *(/,) A/A >A/\/ OH I/ OH co/!-form CH2The a-form, which gives rise t o acidic products on ozonisation, isprincipally found in eudesmol prepared from selinene dihydrochloride(Semmler and Risse's selinenol),63 since elimination of hydrogenchloride usually tends to produce the form with the double bondin the ring; the @-form predominates in the natural product (fromthe oil of Eucalyptus Macarthuri). The melting point and rotationof eudesmol do not appear to be notably affected by its composition.Several alcohols of the sesquiterpene series, such as machil01,~~cryptomerad01,~~ and the alcohol from the bark of MugnoZia Ovata,66are identical with eudesm01.~~Of more than passing interest is the discovery of three crystallineketones closely related t o eudesmol, which have been isolated fromthe wood oil of Eremophila Mitchelli, since they are amongst63 Ber., 1912, 45, 3305; A., 1913, i, 66.64 S.Takagi, J . Pharm. SOC. Japan, 1921, 41, 473; A., 1921, i, 721.65 H. Wienhaus and H. Scholtz, Ber. Schimnzel and Co., 1929, 267; A . ,66 Y. Sugii and H. Shindo, J . Pharm. SOC. Japan, 1930, 50, 103; A., 1931," L. Ruzicka, D. R. Koolhaas, and A. H. Wind, H e h . Chim. Acta, 1931,1929, 1308.267.14, 1151; A., 1931, 1302RON. 155the first cyclic ketones of the sesquiterpene series so far discovered ;moreover, their structure has been completely elucidated.68 Theyare eremophilone (VII), 2-hydroxyeremophilone (VIII), and2-hydroxy- I :2-dihydroeremophilone (IX) :Me(VII.) (VIII.) (IX.)Eremophilone is dehydrogenated by selenium t o eudalene andcontains two double bonds, one of which is ap- to the keto-group,since it forms an unstable addition product with hydrogen sulphideand an oxide with hydrogen peroxide ; the formation of a hydroxy-methylene compound shows that there is a CH, group next to theketo-group, i.e., the system :CH*COCH2-.In accordance with this,reduction with sodium and alcohol leads to dihydroeremophilol(X), which on ozonisation yields formaldehyde and a hydroxy-ketone, C14H2402 (XI), further oxidised by hypobromite to anacid, C1,H2,O, (XII) :(X.)The double bond which(XI.) (XII.)escapes reduction and is here shown tobe in the side chain, must be independent of the conjugated system:CH*CO*CH,* and the latter must therefore be situated in the ringnot carrying the isopropenyl group. Only two such positions areavailable and a decision between that adopted and the alternativewith t’he keto-group in position 2 can readily be made.Thus, theoxide of eremophilone on treatment with acetic acid and sodiumacetate passes into 2-hydroxyeremophilone, identical with the naturalproduct (VIII). The benzoate of the latter gives acetone and onlya trace of formaldehyde on ozonisation and must therefore consistlargely of the isopropylidene compound; in eremophilone and itsderivatives we are clearly dealing with another case of isomerismsuch as that of eudesmol discussed above. Apart from acetone, theprincipal oxidation product is a mixed anhydride (XIII), formed6s A. E. Bradfield, A. R. Penfold, and J. L. Simonsen, J., 1932, 2744.A. Pfau (Helv. Chim. Acta, 1932,15,1481) claims to have isolated two isomericketones, C15E200, from oil of cedar and another closely related compound fromoil of turmeric, but no experimental details are available156 ORGANIC CHEMISTRY.-PART IT.by cyclisation of the original oxidation product with loss ofwater :The formation of this neutral compound finally establishes theposition of the ketonic group in these compounds.The compound(VIII) is evidently analogous t o diosphenol in the monoterpeneseries.2-Hydroxy- 1 : 2-dihydroeremophilone is oxidised by ozone t oformaldehyde, a ketone (XIV), and only a trace of acetone; thiscompound, like the parent ketone, consists mainly of the isopropenylEorm :(IX.) (XIV.)The position of the keto-group must be the same as in the parentcompound, because 2-hydroxytetrahydroeremophilone, which isobtained from (IX) on catalytic reduction, can be further reducedwith sodium amalgam to tetrahydroeremophilone, in the same waythat hydroxycamphor is reduced to camphor; 69 and the tetra-hydro-compound is oxidised by hydrogen peroxide to a dibasic acidC15H2404, showing that the hydroxyl group is next to the csrbonyl.Artemisin.-Artemisin, which accompanies santonin in ArtemisiaMarina, has been proved to be 7-hydroxysantonin (I).70 Energeticreduction in the presence of platinum oxide gives hexahydro-artemisin (11), which is dehydrogenated to l-methyl-7-ethyl-riapht halene :Me Me(1.) (11.16Q J.Bredt and M. Bredt-Savelsberg, Ber., 1929, 62, [B], 2214; A., 1929,7 O K. Tettweiler, 0. Engel, and E.Wedekind, Annulen, 1932, 492, 105; A , ,1308.371EON. 157The formation of desmotropoartemisin, which is a true phenol,71shows that both the double bonds must be in the same ring ; and theymust occupy the positions shown, because artemisin does not reactwith Caro's acid and therefore has no CH, group next t o the carbonyl.The hydroxyl group in artemisin is tertiary and its position isshown by hydrolysis with alkali, artemionic acid (111) being formed :(I) -+ MeCHl l\i MeCH -\/\ Pl'+MeCH I(111.)OH A/C0,H ' k H (!JO,H dHThis acid can be hydrogenated to a tetrahydro-compound, which canalso be obtained by alkaline hydrolysis of x-tetrahydroartemisin(there are four of these, as required by theory), and is further reducedby sodium amalgam to hexahydrosantonin (IV) :Me(IV.1The hydroxyl group of artemisin can be eliminated by heating withformic acid, artemisene (V) being formed; and this on opening thelactone ring passes into artemionic acid (VI), thus confirming themode of reaction given above :HeZenin.-Helenin, the bitter principle of elecampane root , isrelated to santonin and contains a mixture of lactones, in whichalantolactone and isoalantolactone were identified many yearsago ; 72 K. W. F. H a n ~ e n , ~ ~ and L. Ruzicka and P. Pieth 74 have inaddition isolated dihydroisoalantolactone, identical with the productobtained by reduction by S p r i n ~ . ~ ~ The lactones are accompaniedin the original oil by sesquiterpenes which belong to the eudesmolgroup, being dehydrogenated to eudalene by heating with selenium.7671 P. Bertolo, #azzetta, 1923, 53, 867; A., 1924, i, 304.l2 J. Kallen, Ber., 1876, 9, 154; A., 1876, i, 917.73 Ber., 1931, 64, [B], 67, 943; A., 1931, 360, 734.7 4 Helu. Chim. Acta, 1931, 14, 1090; A., 1931, 1301.7 5 Ber., 1901, 34, 775; A., 1901,76 L. Ruaicka and J. A. van Melsen, Helv. Chim. Acta, 1931,14, 397; A.,325.1931, 734158 ORGANIC CHEMISTRY.-PART II.The lac tones are dehydrogenated to 1 -methyl- 7 - e t hylnap ht haleneand evidently differ only in the position of the double bonds, becauscthey are reduced to the same tetrahydro-derivative, very similar to,but not identical with, deoxytetrahydrosantonin, with which it isprobably stereoisomeric. 77The naturally occurring dihydro-lactone gives on ozonisation aketo-lactone, also obtained by K.W. F. Han~en,'~ which on reduc-tion by Clemmensen's method gives an acid, C,,H,O,, and a hydro-carbon : the latter, also obtained by decarboxylation of the acid, is9-met hyl- 3-ethyl- cis- decalin 78 and yields p - e t hylnaphthalene whenheated with selenium. These changes are formulated as follows :p-Ethylnaphthalene has also been obtained from the dihydro-lactone by Hansen, but by a more direct and therefore less instructiverout'e. These reactions establish the carbon skeleton present in thetwo lactones.The position of the carboxyl and carbinol groups can be inferredfrom the fact that ozonisation, followed by mild oxidation withpermanganate, of a mixture of alantolactone and isoalantolactonegives the acid (XII).76 py) (XI.)H0,C pn +co HOA /\/H0,C COUnstable intermediatc compound.Both lactones are readily reduced to dihydro-derivatives, whiclisuggests that one of the double bonds is in the up-position to thccarbonyl group. This would give rise to formulze (XIII) and (XIV)for the iso-lactone :CO---b CH,(XIII.)As the dihydro-derivatives and &hydrochlorides of the two lactones7 7 Ber., 1931, 64, [B], 1904; A., 1065.' 8 L.Ruzicka, D. R. Koolhaas, a,nd A. H. Wind, Helv. Chim. Acta, 1931,14,1171; A., 1931, 1302KON. 159are different, the double bond not adjacent to the carbonyl groupmust also be differently situated in the two isomerides. Ozonkationof dihydroalantolactone gives a ketonic acid (XV), showing that thedouble bond in question is situated in the ring.The addition ofhydrogen chloride to this double bond must inevitably produce anarrangement identical with that resulting from the semicycliciso-lactone ; and as the two dihydrochlorides are different, theymust be represented by the formula? (XVI) and (XVII). The twolactones therefore most probably have the structures (XIII) and(XVIII) :(XVI.) (XVII. ) (XVIII.) AlantolactoneHansen 77 favours the formula (XIV) for the iso-lactone; shouldthis prove to be correct, the formula (XVIII) for alantolactone wouldalso require revision, since both (XIV) and (XVIII) would give riseto the same dihydrochloride.The Resin Acids (continued from Ann. Reports, 1927, 24, 124).-Considerable progress has been made in the elucidation of thestructure of abietic and dextropimaric acids and the formulaassigned to them have attained some degree of certainty.The new facts are as follows : oxidation of either acid with a largeexcess of permanganate leads to two acids, CllH1606 and C1,H1,06.79The former is dehydrogenated by selenium to m-xylene, and thelatter to 1 : 2 : 3-trirnethylben~ene.8~ In these acids ring I of theparent acids is intact and it can be concluded that the methyl groupwhich is lost in the dehydrogenation of abietic acid to reteneoccupies position 12, not 11 as hitherto supposed :Me Me M U M079 L.Ruzicka, J. Meyer, and M. Pfeiffer, Helw. Chim. Acta, 1925, 8, 637 ; d.,*O L. Ruzicka, M. W. Goldberg, H. W. Euyser, and C.F. Seidel, HeZv.1925, i, 1419; P. Levy, Ber., 1929, 62, 2497; A,, 1929, 1448.Chin&. Acta, 1931, 14, 545; A., 1931, 736160 ORGANIC CHEMISTRY .-PART 11.Later work showed that these formulz required revision nridincidentally supplied the final proof of the position of the carboxylin abietic and dextropimaric acids. F. Vocke 81 found that the C,,acid has two carboxyls attached to tertiary carbon atoms, and thesame conclusion was independently reached by L. Ruzicka, G. B. R.de Graaff, and H. J. Miiller.S2 It had previously been found thatmethylabietin, in which a methyl group replaces the carboxyl, isdehydrogenated to a methylretene, and methylpimarin, similarlyderived from dextropimaric acid, yields a meth~lpimanthrene.~~It has now been found 82 that these compounds are oxidised to thesame phenanthrene-1 : 7-dicarboxylic acid and that they are there-fore homoretene (111) and homopimanthrene (IV) respectively :(111.) W.) (V.) WI.)This means either that the carboxyl in the resin acids is attached toa methyl group as in (V) or that both groups are attached to thenucleus in position 1 as in (VI). The former alternative is contraryto the " isoprene rule " and does not account for the difficult esteri-fication of these acids, which is adequately expressed by formula (VI).The formation of an ethyl group in the dehydration of abietinol isdoubtless due to a pinacolic change :CH,-CH, - EtMe CH,.OH- [ 6 ] + I\ fi I 1The same conclusion was independently reached by R. D.HaworthYs5 who, in addition, synthesised homoretene and homo-pimanthrene and placed their structure beyond all doubt.The acid andits ester combine with maleic anhydride 86 and therefore contain asystem of conjugated double bonds, the possible positions of whichare represented in formula (VII) by thick lines; of these, theThe skeleton of abietic acid is thus finally settled.81 Annalen, 1932, 497, 247 ; A., 1036.82 Helv.Chim. Acta, 1932, 15, 1300; A . , 1255-1.83 Ann. Reports, 1827, loc. cit.85 J., 1932, 2717.a 6 L. Ruzicka, P. J. Ankersmit, and B. Frank, Helw. G'him. Acta, 1032, 15,1289; rl., 1254KON . 1619 : 14-position is considered to be excluded for steric reasons and thearrangement (VIII) is the most likely :Dextropimaric acid does not form an addition product withmaleic anhydride and therefore does not contain a system of con-jugated double bonds.On oxidation with excess of permanganateit gives the same two acids (I) and (11), and therefore has the samesubstituents in ring I, as abietic acid; 87 on ozonisation it givesformaldehyde, proving the presence of a terminal CH, group.The following formule are therefore considered likely :Of these, (IX) is much the more probable because tetrahydro-dextropimaric acid is dehydrated by selenium to pimanthrene, aswould be expected; from a compound of the alternative structure,some 1-methyl-7-ethylphenanthrene should be formed.The suggested formuh for abietic and dextropimaric acids arederived from irregular isoprene chains :~ .~ . ~ . ~ . ~ ~ . ~ . ~ . ~ . c! Q ' F ! $-J.c.c.c. Q -Abietic acidDextropimaric acid ~ ~ ~ ~ ~ ~ ~ * ~ ~ F! ' Q 9 '1 :iQi 1 ICAgathic (more strictly, agathicdicarboxylic) acid, C,H,,O, (XI),p<esent in manila or kauri copal, contains two rings and two doublebonds 88 and gives on dehydrogenation with selenium 1 : 2 : 5-tri-methylnaphthalene and a hydrocarbon C,,H,, (XII). On treatmentwith formic acid a further ring is closed, forming isoagathic acid8 7 L. Ruzicka, G. B. R. de Graaff, M. W. Goldberg, and B. Frank, HeZw.Chi,m. Acta, 1932, 15, 915; A., 948; R. D. Haworth, loc. cit.8 8 L. Ruzicka and J. R. Hosking, Annakn, 1929, 469, 572; A , , 1929, 572.REPe-VOL. XXIX. 162 ORGANIC CHEMISTRY .-I'ART 11.(XIII),89 which contains one double bond and is dehydrogenated LOpimanthrene; a small amount of the latter is also produced fromagat hic acid it self.Me\/Me/\A Me,/Me I A/\ '\(,"" JY I I1 I- H0,C c1\@2H AAk H ,Me H0,C(XI.) (XII.) (XIII.)One carboxyl group is lost by agathic and isoagathic acid onmelting, noragathic and norisoagathic acid respectively beingformed.One ester group in methyl agathate is readily hydrolysedand the free carboxyl also is easily split off, leading to methylnoragathate ; the latter is only hydrolysed with extreme difficulty,and the same applies also to the second ester group in methylagathatc and to both ester groups in methyl isoagathatc. The firstcarboxyl is therefore probably situated next to a double bond in theside chain, on a carbon atom which is involved in the conversion ofagathic acid into the iso-acid, since the character of this carboxyI .changes completely on cyclisation of the acid.The same doublebond is also t'hc only one t o bc reduced by sodium and alcohol andif it is o$ to the carboxyl, it is probable that there arc no othersubstituents in the vicinity. The results of ozonisation, which givesformaldehyde, formic and oxalic acids, also support this formulationand confirm the presence of the terminal CH, group in agathic acid.The second carboxyl must occupy a sterically protected position,being quite different from the carboxyl in abietic or dextropimaricacid ; and on the assumption that the acid is derived from a regulararrangement of isoprene units, the position 12 for this group is to bepreferred to the alternative one, 11.Moreover, one carbomethoxyl group of methyl isoagathate can bereduced, though not so easily as that in methyl agathate ; the carb-inol group is then converted into methyl, and the product ondehydrogenation with selenium passes into a new trimethylphen-anthrene. This shows that the carboxyl which is not reducedoccupies a different position from that in abietic acid :Me\/Me Me\/Mc:AA (SIIl'r _3 llile _3 1 l,Xe G."/\&HO,C Li\(jcF* OH H02C j / M c8 9 L.RiuiCka aiid J. t:. tlouliiiig, Helu. C'hiiu. dcta, 1930, 13, 1402; 1031,14, 203; A . , 1931, 231, 359KON.The diterpenic alcohol sclareol, from the oilappears to be closely connected with agathic acid.alcohol with a terminal CH, group oxidisableconverted into 1 : 2 : 5-trimethylnaphthalene on - -The probable formula (XIV) is put forward for it.90Me\ /Me163of Salvia sclarea,It is a ditertiaryto formaldehyde,dehydrogenation.(XIV.)A considerable amount of work has lately been carried out onelemic acid, a triterpene derivative, and the related amyrins andsapogenins but the results are not yet ripe for summarising; mostauthorities, however, now agree that the sapogenins are triterpenederivatives with a C3,, formula.Polycyclic Hydrocarbons.Apart from the technical importance of a number of the morecomplex hydrocarbons of this group, increasing attention has latelybeen devoted to the possibility of determining the fine structure ofthese compounds ; the results indicate that speculation has pro-gressed beyond mere guesswork and give a logical explanation ofotherwise obscure differences between closely related compounds,such as the great difference in meso-reactivity between phen-anthrene and anthracene or, better still, 1in.-benzanthracene, whichdoes not immediately follow from their formuke.A sensitive testof such reactivity is the reaction of these compounds with maleicanhydride 91 or benzoquinone ; 92 thus, phenanthrene does not addthe former reagent, whereas anthracene does so readily.93 Theabsorption spectra provide another means of investigation andnumerous measurements of extinction coefficients have been made ;the results of these physical measurements are in good agreementwith those of purely chemical investigations.E. Clar’s basic assumption is that these hydrocarbons exhibitM.M. Janot, Corn@. rend., 1930,191,847; 1931, 192, 845; A., 1931, 94,9 1 0. Diels and K. Alder, Annalen, 1931, 486, 191 ; A., 1931, 848; E. Clar,92 E. Clar and F. John, ib,id., 1930, 63, [BJ, 2967; E. Clar, ibid., 1931, 64,93 E. Cler, ibid., 1932, 65, [B], 1485; A., 1131.737.Ber., 1931, 64, [ B ] , 2194; A., 1931, 1292.[BJ, 1676; A., 1931, 209, 1044164 ORGANIC CHEMISTRY.-PART II.valency tautomerismg4 leading to two or more forms, which inanthracene, for example, are (I) and (11) :o-quinonoid formThe second form, referred toelectrons on the meso-carbonH”diradical formas the “R” state, has unsharedatoms and is responsible for thereactivity of these positions, which varies according to the perman-ence of this phase in different compounds.95 It is also responsiblefor the characteristic anthracene absorption bands in the long-waveregion of the spectrum.The catalytic hydrogenation of anthracene, which has lately beenre-e~amined,~~ is readily interpreted in the light of this conception :e.g., the formation of the 9 : 10-dihydride is not an intermediate stepin, but takes place concurrently with, the formation of the 1 : 2 : 3 : 4-tetra- and the 1 : 2 : 3 : 4 : 5 : 6 : 7 : 8-octa-hydride.The dihydride,being a true benzene derivative, is much more slowly hydrogenatedthan anthracene itself, and similarly the octahydride is only slowlyattacked. The dihydride is presumably derived from the “ R ”state, whereas the quinonoid form is directly hydrogenated t o thehigher hydrides, without passing through the dihydride as postulatedby G.S~hroeter.~’ *The degree of mobility of the unshared electrons in the “ R ” phasevaries with the valency demand of the arylene residues fused to themeso-ring and with it the depth of colour of the substance. Forinstance, 2 : 3-benzanthracene (111), which is more reactive thananthracene, is orange and is photochemically oxidised to the quinonewhen its xylene solution is shaken with air ; and 2 : 3 : 6 : 7-dibenz-anthracene (IV) is deep blue,g* forms a bimolecular peroxide onphotochemical oxidation, and instantaneously reacts with maleicanhydride. This indicates that it exists solely in the “ R ” state andit is actually termed 2 : 3 : 6 : 7-dibenzanthracene-9 : 10-diyl; inagreement with this, its blue solutions do not darken further on94 E.Clar and F. John, Zoc. c i t .95 E. Clar, Ber., 1932, 65, [B], 503; A., 608.O 6 K. Fries and K. Schilling, ibid., p. 1494; A., 1123.07 Ibid., 1924, 57, 2003 ; A., 1925, i, 127.98 E. Clar and F. John, ibid., 1930, 63, [B], 2967; A., 1931, 209.* The formation of the tetrahydride from the dihydride, which has beenestablished by Schroeter, may proceed through the intermediate dehydrogen-ation to anthracone, which has been isolated from the hydrogenation productof the dihydrideRON. 165heating, an effect observed in some anthracene derivative^,^^ anddissociation is evidently complete.\/\/+A/ //H" H"(" R " phase alone shown.)On the other hand, 1 : 2 : 5 : 6-dibenzanthracene (V) reacts slowlywith maleic anhydride and is colourless ; it is a curious fact that itscarcinogenic activity is apparently not directly connected with itschemical reactivity : 1(VI.) (VII.)Now these hydrocarbons can be considered to be derived fromquinones; thus, anthracene and 2 : 3-benzanthracene, in its sym-metrical form (VI), both embody the skeleton of o-benzoquinone.Clar suggests that there is a simple relationship between the reduc-tion potentials of the quinones and the extinction curves of the relatedhydrocarbons.A number of these potentials have been determinedby L. F. Fieser and his collaborators ; when plotted against log cmax.of the corresponding hydrocarbons, they give a straight line, andthus the reduction potential of an unknown quinone can be predictedif the absorption spectrum of the relevant hydrocarbon is known.Hydrocarbons related to a quinone with a low reduction potentialhave a short " R " phase and exhibit diminished meso-reactivityand vice versa; and the corresponding effect is observed in thedisplacement of the " A " absorption bands of the spectrum.2 : 3-Benzanthracene in its unsymmetrical form (VII) is derivedfrom the (presumably highly reactive) unknown 2 : S-naphtha-quinone.Similarly, 2 : 3 : 6 : 7-dibenzanthracene can be derivedfrom the latter or from the likewise unstable 2 : 3-anthraquinone;owing to the instability of these quinonoid forms the compound tendsto exist more and more in the free radical or " R " state, until in thelimiting case of the 2 : 3 : 6 : 7-compound this becomes the onlystable condition.n9 C.K. Ingold and P. G. Marshall, J., 1926, 3080; A., 1927, 141.1 J. W. Cook, J., 1931, 3273; A., 153.J. Amer. Chern. Soc., 1924, 46, 1864; 1929, 61, 3101; 1930, 52, 5204;A:, 1924, ii, 839; 1929, 1452; 1931, 173166 ORGANIC CHEMISTRY.-PART II.All the extinction curves show, in addition to the ‘( A ” bands, anintense band of clearly benzenoid character, though somewhatdisplaced. The paleic anhydride addition product of anthraceneshows a typical benzene spectrum, although it is displaced in thesame way, but the corresponding compound from 1 : 2-benzanthra-cene (VIII) is a typical naphthalene derivative.The free hydro-carbon also shows some characteristics of the naphthalene spectrum,but no trace of this is seen in 2 : 3-benz- and 2 : 3 : 6 : 7-dibenz-anthracene, although it reappears in their addition products withmaleic anhydride. It is clear that in the latter the effect of theunshared electrons due to the “ R ” state is no longer observed andthe spectrum is entirely due to the benzene (or naphthalene) rings a tthe side :H*C 0 I / H T I CH*CO I /H I 1 I t /yI CHdO H H IIt can be concluded that the naphthylene residues must have adifferent structure in ang.- and Zin.-hydrocarbons derived fromanthracene; in the former it is symmetrical and in the latterunsymmetrical :It also follows that the Zin.attachment of rings t o anthracenestabilises the diradical state, whereas the aromatic state is favouredby their ang. attachment, which causes a general diminution ofreactivity and increase in stability. In accord with this is theobservation that the stability of dihydro-derivatives of these com-pounds goes hand in hand with their increasing meso-reactivity. Asimilar parallelism has already been recorded in the benzonaphth-azines .4Phenanthrene has clearly a less pronounced “ R ” phase thananthracene and is therefore less reactive in the meso-positions ;at the same time the 1 : 4-positions display a certain reactivity, e.g.,L. F. Fieser, J . Amer. Chem. SOC., 1931, 53, 2329; A., 1931, 1064.0. Hinsberg, Annalen, 1901, 319, 264; A ., 1902, i, 238.E. Clar and L. Lombartii, Uer., 1932, 65, [R], 1411 ; A., 1123RON. 167towards lithium,s and a second diradical phase (XI) may have to betaken into consideration :The structure (XI), like (X), is that of a naphthalene derivative, andthis is distinctly shown in the extinction curve of the hydrocarbon,in addition to the intense benzene band already noted in the anthra-cene spectrum. Chrysene (XII) evidently has a similar structurebut with a longer 9 : 10-diyl phase. Triphenylene shows a naphth-alene-like spectrum; its dirndical phase is evidently the 1 : 4-diyl(XIII) :(XII.) (XIII.)On the other hand, the curve of 2' : 3'-naphtha-2 : 3-phenanthrene(XIV), a deep orange, highly reactive substance, shows no vestigeof phenanthrene character ; it is just like that of 2 : 3-benzanthra-cene, but reverts t o the phenanthrene type when (XIV) combineswith maleic anhydride.CO-CH- IOn the assumption fhaf naphthalene has an unsyminetricalstructure derivable from that of o-benzoquinone, chryscne, phen-anthrene, and triphenylene could be respectively linked up with1 : 2-phenanthraquinone, 1 : 2-naphthaquinone, and 9 : 10-phen-anthraquinone ; the reduction potentials of these quinones are notsimply related to the log E ~ ~ ~ .as in the anthracenes and it is concludedthat in all hydrocarbons formed from naphthalene by ang. attach-ment of phenylene residues there is a double bond between any twoW. Schlenk and E. Bergmann, Annalen, 1928, 463, 84; A., 1928, 1031.7 L.F. Fieser and M. A. Peters, J. Amer. Chent. Roc., 1931, 53, 703; A . ,1033, 480168 ORGANIC CHEMISTRY .-PART 11.rings ; this explains the inability of these hydrocarbons to react withmaleic anhydride.Perylene presents special interest, being the basis of an importantgroup of colouring matters, and has been the subject of repeatedinvestigation. It is reduced by sodium in amyl alcohol,s givingsimultaneously an octahydro- and a tetradecahydro-compound,(XVI) and (XVIII) ; the first is formed in the same way as tetralinfrom naphthalene, and the formation of the second is like thehydrogenation of anthracene. It is suggested that the isomericforms of the hydrocarbon (XV) and (XVII) give rise to thesereduction products, just as two quinones, the 3 : 9- and the 3 : lo-,are formed on oxidation :/LkI3 -(XV.)7 81 11 111 \A/ 9 10(XVI.)I II I I/\,AII 1 I(XVII.) (XTX.)E. Clar regards formula (XV) as improbable, because the middlering is triquinonoid and, although the positions 6 : 7 and 1 : 12 areexactly equivalent, perylene reacts with only one molecule of maleicanhydride : this and the preferential formation of the 3 : 9-quinoneare only explained by the formula (XIX), which is also supported byspectrographic evidence. Thus (XV) contains two naphthaleneresidues which should find expression in the extinction curve andthis is not observed ; also, the spectrum of the 2 : 3 : 10 : ll-dibenzo-compound (XX) is very similar to that of the parent hydrocarbon,whereas the addition of two rings to the structure (XV) should causea marked alteration, similar to that observed on passing fromnaphthalene to phenanthrene. On the other hand, the curveof the 1 : 12-benzo-compound (XXI), though still of the perylene* A.Zinke and 0. Benndorf, Monatsh., 1932, 59, 241 ; A., 507.9 Ber., 1932, 65, [B], 846; A., 731RON. 169type, is less intense and evidently corresponds to a more saturatedstructure ; the bands are displaced towards the ultra-violet, doubtlessowing to the inclusion of the double bonds of the quinonoid systemin the new benzene ring.\/The anthraquinonoid formula (XVII), however, accounts for someof the reactions of perylene and is retained ; the distinctive characterof perylene is attributed to the conjugated system 3 : 10 (markedwith asterisks in formula XIX).Benzanthrone is easily reduced, taking up four atoms ofhydrogen,1° and behaves towards the Grignard reagent as an unsatur-ated ketoneg This behaviour is held to indicate that an equilibriumexists between the forms (XXII) and (XXIII) :9-(XXIII.)(XXIV.)Benzanthrene (XXIV), formed by replacing the carbonyl groupof benzanthrone by a methylene group, gives a typical naphthalenespectrum as would be expected from the above, but not from thealternative, anthracene-like, formulation ; its reactivity, e.g., withmaleic anhydride, is due t o the conjugated system marked byasterisks (compare perylene).This arrangement is not present inbenzanthrone, which, like phenanthrene and chrysene, does not forman addition product.These differences in reactivity are inexplicablelo J. v. Braun and 0. Bayer, Ber., 1925, 58, 2667; A., 1926, 172.F 170 ORGANIC CHEMISTRY .-PABT 11.on the basis of such formulz as J. J. Thornson’s (Pt5dulescu’sformula, XXVI) and give strong support for a formulation withactual double bonds disposed in a definite rnanner.llRecent experiments suggest that the electromeric phases in poly-cyclic compounds can have considerable stability ; l2 e.g., 2-retenol(XXV) does not couple with diazotised amines. The addition of thelatter would norma.lly occur either at a. double bond or at the end ofa conjugated system (Le., ortho or para to the hydroxyl), but neitherof these alternatives (marked by asterisks) is available and nocoupling occurs :MeD.Riidulescu and his collaborators l3 have measured the extinc-tion curves of a number of organic compounds, including ant,hracene,phenanthrene, pyrene, perylene, and 2 : 3-benzanthracene, andinterpreted them in the light of his theoretical views, which cannot beconveniently summarised . He also assumes valency tautomerismin polycyclic hydrocarbons and his conclusions, based on spectro-graphic work, are similar to Clar’s. His formulae are, however,different ; those adopted for anthracene, for example, are (XXVI)and (XXVII) ; the latter thus corresponds t o a para-bridged phase,and the former is J. J. Thornson’s original electronic formula :The spectral bands due to the bridged phase are the “ A ” bands inthe long-wave region attributed by Clar to the “ R ” phase.Theessential difference, therefore, between these formuh is that in thebridged one the odd electrons are controlled by both meso-carbons,whereas in the diradical formula t’hey are unshared. E. Clar andmany others are strongly opposed to the bridged formulation, whichin any case cannot account for the behaviour of compounds such as2 : 3 : 6 : 7-dibenzanthracene-9 : 10-diyl, the diradical nature ofwhich appears to be beyond dispute, and it seems to the Reporterl1 E. Clar, Ber., 1932, [B], 65, 1425; A., 1131.l2 L. F. Fieser and M. N. Young, J . Amer. Chern. SOC., 1931, 53, 4120; 44.,163. The experiments of A. A. Levine and A. G. Cole (ibid., 1932, 54, 338 ;A., 259) on the ozonisation of o-xylene prove the separate existence of the twoKe kul6 individuals.13 Ber., 1031, 64, [B], 2223 et seg.; A., 1931, 1361EON.171that, even if the existence of a bridged phase is admitt'ed, this cannotsupersede the diradical phase. The limiting phases required toaccount for the facts are the quinonoid and the diradical.The synthesis of coronene (hexabenzobenzene) by R. Scholl andK. Meyer l4 was made possible by the discovery l5 that the chloridesof anthraquinone-l-carboxylic acids react in two tautomeric forms(I) and (11), in both of which the chlorine can be replaced by anaromatic residue by the Friedel-Crafts reaction. Thus the chlorideof anthraquinone-1 : 5-dicarboxylic acid condenses with m-xylene,giving mainly the compound (111) ; this is oxidised by permanganateto the lactonic acid (IV), which is reduced with hydriodic acid andphosphorus to the hexacarboxylic acid (V) :(111.)l4 Ber., 1932, 65, [B], 902; A., 731.l6 R.Scholl, H. Dehnert, andL. Wanka, Annakn, 1932,493,56; R. Scholi,H. K. Meyer, and W. Winkler, ibid., 494, 201 ; A., 274, 617172 ORGANIC CREMISTRY .-PART II.The acid (V) can undergo ring closure in several different ways :20% oleum produces the compound (VI), which can be reduced withfurther ring closure to the acid (VII), from which, by heating withsoda-lime and copper powder, dibenzocoronene (VIII) is obtained.This, treated with dilute nitric passes through a red diquinone (IX),giving a blue vat, into the acid (X), which is decarboxylated withsoda-lime to coronene itself (XI).HI+P ___,4C0,H(VII.)H0,C C0,H @H0,C C0,H(X.1(VIII. )The hydrocarbon is pale yellow with a blue fluorescence, high-melting,and extremely stable. These properties are best expressed by theformula (XI), in which the central ring is a true benzene ring and thedouble bonds in the peripheral ring system form a continuousconjugated system.The dibenzo-compound (VIII) forms a complete contrast tocoronene; it is highly coloured, and its red solutions have a greenfluorescence and are readily oxidised in the air ; it is readily convertedinto the quinone (IX) and gives a dark blue dibromide (probably acarbonium salt). Such reactivity suggests a diradical structure(XII) ; the authors, however, prefer the alternative structure(VIII), which in their opinion suffices t,o explain the behaviour of thesubstance.They also suggest electronic formulae (XIII) and (XIV)for dibenzocoronene and coronene, in which the thick lines representthree-electron linkages and the fine lines two-electron linkagesxox. 173These are open to the mme objections aa the non-committal formulsdiscussed on p. 170.(XIII.) (XIV.)The Reporter wishes to thank Dr. J. W. Cook for many helpfulsuggestions.Rubrenes.No account has yet been given in these Reports of a remarkablegroup of substances discovered in 1926.16Rubrene, the type of the series, is a red hydrocarbon, C42H28,dissolving in benzene with a yellow fluorescence, and is prepared byheating the chloride (I) :On oxidation with chromic acid 17 rubrene gives o-dibenzoylbenzeneand carbon dioxide, in accordance with the structure (11; Ar = Ph)assigned t o it.18(1.) 2Ph2CC1*CiCPh = C4,H2, + 2HC1A r / '.Ph(11.) / (, \p" /&Rp + I /\ ~~-cOPh+CO, COPh\\ y$ ,,x& // \/-The dibenzofulvene formula (11) accounts satisfactorily for thecolour and fluorescence of rubrene and its mode of formation. Themechanism suggested for the latter as the most likely 18 involves,fist of all, the migration of the chlorine from the CI- to the y-carbonatom of the acetylenic compound, a process analogous to themigration of the hydroxyl group in the corresponding carbinol19(111), which readily passes into the ketone (IV) :1@ C. Moureu, C. Dufraisse, and P. M. Dean, Compt. rend., 1926, 182, 1440;A ., 1926, 945.1' C. Moureu, C. Dufraisse, and L. Enderlin, ibid., 1928,187,406; A., 1928,1127; C. Dufraisse and L. Enderlin, Bull. SOC. chim., 1932, [iv], 51, 132; A.,507.l* A. Willemart, Compt. Tend., 1928, 187, 385; A., 996; Ann. Chim., 1929,[XI, 12, 345; A., 1930, 334.19 K. H. Meyer and K. Schuster, BeT., 1922, 55, 819; A,, 1922, i, 556174 ORGANIC CHEMISTRY.-PART II.(111,) Ph,C(OH)PhCiCPh++ Ph2C:C:F*Ph =OHCPhPh,C:CH*COPh (1v.1CPh -1J. Robin 2O has made a further study of the formation of rubrene.He finds that the chloride (I) passes on keeping or on treatment withammonia or an aliphatic amine into a compound still containinghalogen, evidently formed by loss of one molecule of hydrogenchloride from two of the acetylenic compound.The new compoundpasses easily and quantitatively into rubrene and is formulated as ahydrochloride such as (V) or (VI) :PhC CPh CPh CPhC1the corresponding hydroxy- and et hoxy-compound have also beenobtained .With aniline (and other primary nrylamines) the chloride (I) formsa colourless (VII) and a yellow (VIII) nitrogenous derivative ; theformer is converted into the latter when heated with aniline hydro-chloride, and its hydrochloride undergoes the same change, especiallyin aniline solution.( ~ 1 1 . 1 Ph2(i*CICPh -+ Ph,C:CH$Ph (VIII.)NHPh NPh(VIII) can be hydrolysed to the ketone (IV) and its constitution isthus proved. The change therefore provides an interesting exampleof tautomeric change similar to that observed by Meyer andSchuster.lg Robin prefers to formulate it as involving the additionof hydrogen chloride, which is then eliminated as aniline hydro-chloride, on the ground that hydrogen chloride is indispensable forthis transformation :20 Ann.Chim., 1931, [XI, 16, 421; A., 1932, 260; compare C. Moureu, C.Dufraisse, and J. Robin, Compt. rend., 1929, 188, 1582; A., 1929, 922RON. 176Similarly, he assumes the intermediate addition of hydrogen chlorideto the chloride (I) in the conversion of the latter into rubrene :A/\ CPh reh=] --+ I II c -+\/ // \ \/ClCPh Cl*CPh 9The cyclisation of the compound may take place either before or afterthe elimination of hydrogen chloride .This view of the process is, like all similar theories, difficult todisprove, but nevertheless appears t o be superfluous when accountis taken of the proved occurrence of tautomeric changes in similarlyconstituted ethylenic systems ; in addition, Meyer and Schuster 19have shown that the analogous transformation of the correspondingcarbinol cannot be due t o the addition and elimination of water,since it proceeds most readily in the presence of strong dehydratingagents (acetic anhydride) and bears a marked resemblance to thechanges subsequently examined by Burton and Ingold.21The early experiments indicated that only chlorides of the typePh,CCl*CiCAr gave rise to rubrenes, but unsymmetrical compoundsof the type PhArCClCiCAr have since been successfully employed : 22the former can furnish only one rubrene ; a compound such as (IX)can give rise to three different rubrenes, one of which should beidentical with that obtained from the isomeric chloride (X). Thisprediction is verified by experiment and provides good support fort,he scheme of formation of rubrenes given above.\/ //CPh Ph Phc1 .*C 'IPhCPh21 J ., 1928, 904; A . , 1928, 634; compare Ann. Repo~ts, 1928, 25, 127.32 C. Dufraisse and &I. Loury, Cornpt. Tend., 1932,194, 1664, 1832; A . , 732176 ORQANIC CHEMISTRY.-PART If.C. Dufraisse and R. Buret 23 have prepared a rubrene (XI), inwhich two of the phenyl residues are replaced by chlorine, from theketone (XII) by the action of phosphorus pentachloride.Ph PhThe most remarkable property of the rubrenes is their ability toabsorb oxygen on irradiation; no reaction t'akes place in the dark.15A solvent such as benzene is also necessary ; no reaction takes placein water or acetic acid, in which rubrene is insoluble,24 but even arapidly oxidisable solvent such as benzaldehyde can be employed." Antioxygens '' such as quinol or resorcinol retard the reaction, buttheir effect is purely chemical and not due to screening.The completion of the change is marked by the disappearance ofcolour and especially fluorescence.The product is an oxide, RO,,crystallising with half a molecule of benzene or other solvent ofcrystallisation, from which it cannot be freed without decomposition ;it has the remarkable property of giving up its oxygen when heated,regenerating the parent hydrocarbon, the change being accom-panied by an emission of light.Its formation and dissociation cantherefore be written : R + 0, + lightThis dissociable dioxide, oxyrubrene, is reduced by zinc and aceticacid to a monoxide, metrubrene, which can also be obtained by themild oxidation of rubrene with permanganate or chromic acid; 25this can be reduced to rubrene but cannot be oxidised to oxyrubrene.Oxyrubrene is isomerised by the action of a Grignard reagent toisooxyrubrene, which no longer dissociates when heated, but canbe reduced to rubrene26 and therefore contains the same carbonskeleton. The formulae (XIII) and (XIV) are suggested for theseRO,.two oxides.Ph Ph Ph Ph// *A/\ II II C=C II I 4 4 A/\I II C-C II I \/yqV \\/Y.\r.Ph h h Ph(XIII.) Metrubrene (XIV.) isooxyrubrene23 Compt.rend., 1932, 195, 962.24 C. Moureu, C. Dufraisse, and C. L. Butler, ibid., 1926, 183, 101 ; A,, 1926,25 C. Moureu, C. Dufraisse, and L. Enderlin, ibid., 1929, 188, 1528; A.,$ 6 C. Dufraisse and &I. Bucloche, ibid., 1930, 191, 104; A., 1930, 1173.945.1929, 922EON. 177The relationship between rubrene, metrubrene, and oxytwbrene isremarkably like that between hamoglobin and its oxidation productsand the names of the compounds are intended to emphasise thissimilarity : 26Rubrene Hemoglobinred.Oxyhaemoglobin -3 Methaemoglobin Oxyrubrene -3 MetrubreneSuch reversible oxidations are unknown except in the respiratorypigments, in which this property has generally been connected withthe presence of iron in the molecule.Oxidations are usually accom-panied by a considerable liberation of energy and would not beexpected to be reversible for that reason.The heats of formation of rubrene and its oxides are as follows : 27Rubrene. Oxyrubrene. isooxyrubrene. Metrubrene.- 131 - 108.4 - 50.4 - 92-4The difference between the heats of formation of rubrene andoxyrubrene (23 cals.) is less than the heat required for t'he formationof an oxide ring (50 cals.) or a carbonyl group (100 cals.). Neverthe-less, the photochemical formation of oxyrubrene is exothermic andthe activating action of light can presumably be replaced by someother catalytic influence.An interesting transformation has been observed as the result ofthe prolonged action of a Grignard reagent on isooxyrubrene.28The product is a magnesium derivative which on treatment withwater gives phenol and a rubrene (I1 ; Ar = H) containing one phenylgroup less than the initial material; similarly, with iodine, an iodo-rubrene (11; Ar = I) k produced, and with carbon dioxide thecorresponding carboxylic acid :C,,H2,O2 + 2Mg = C36HB*Mg*OPh + MgO -+ PhOH + Ca6H2*.The compound (I1 ; Ar = H) is a typical rubrene, forming a dissoci-able oxide and having the other characteristic properties of the class.The iodo-compound (11; Ar = I) on treatment with sodiumet hoxide loses hydrogen iodide and forms a violet hydrocarbon (XV),the change probably taking place as follows : 29/-\I \=(27 c.Dufraisse andL. Enderlin, Compt.rend., 1930,191,1321 ; A., 1931, 171.2 8 C. Dufraisse and M. Badoche, ibid., 1931, 193, 242; A., 1931, 1151.*Q Idem, ibid., p. 529; A., 1931, 1407178 ORGANIC CHEMISTRY .--PART 111.The intensification of colour is to be expected, since a naphtha-quinone group is present in the new compound in addition to therubrene skeleton, which remains intact.Sterols and Rile Acids.The year under review has seen important developments of thissubject, discussion of which must be deferred until next year owingt o lack of space. A summary of the present position with regardto the bile acids and cholesterol has been published by A.Windau~.~OG. A. R. KON.PART III.-HETEROCYCLIC DIvrsroN.HETEROCYCLIC chemistry of to-day is almost synonymous with thechemistry of heterocyclic natural products. The past 50 yearshave been spent in perfecting the implements with which the organicchemist of to-day works.Discoveries of new methods of wideapplicability, such as the remarkable " diene '' synthetic andanalytic methodof 0. Diels and K, Alder,l must of necessity be fewand far betwecn. A new chemistry is, however, arising which has aboundless future before it-chemistry under natural or biologicalconditions. Already we have some striking examples of its applic-ability, especially in the field of alkaloidal chemistry,I n 1905 A. Pictet suggested that alkaloids arofie from proteinsand amino-acids and the view was developed by E. Winterstein andG. Trier,2 who appear to have been the first to suggest a biogeneticmechanism for the isoquinoline group. The thesis was however,put in an unassailable position by R.Robinuony3 who illustrated itby syntheses of tropinone 4 and +pelletierine by methods whichmight occur in the plant, and extended it by the synthesis of N -methylhomogranatoline 6 and some analogues of $-pelletierine.7From Angostura bark, E. Spath and his co-workers isolated andidentified a series of quinoline alkaloids which an account of thcirsimilarity of structure were thought to arise in the plant from somecommon parent benzene derivative, probably a derivative ofanthranilic acid. This line of thought has been followed up ex-perimentally by C. Schopf and G. Lehmmqs who find that when30 Z. physiol. Chem., 1932, 213, 147.1 Annalen, 1932, 498, 1, 16; A., 1144.J., 1917, 111, 876; A., 1917, i, 664.R.C. Menzios and R. Robinson, J . , 1921, 125, 2263 ; A ., 1924, i, 13%;.B. K. Blount and R. Robinson, J . , 1932, 1429; A . , 759." Die Alkaloido," 1910.Ibid., p. 782; A., 1917, i, 581,7 Idem, ibid., p. 2485; A . , 1147. Annulen,, 1932, 497, 7 ; A . , 104GKING. 179o-aminobenzaldehyde and acetone are brought together in diluteaqueous solution of p H 3, 5, 7 or 9 no quinaldine is formed but atpH 12-13 a smooth Friedlander synthesis occurs with formation ofquinaldine. If, however, acetone is replaced by acetoacetic acid,a 90% yield of quinaldine may be obtained afterpH 6.8.16 days at 25" and+ co, + 2H,OIf the reaction is carried out at pH 13, no loss of carbon dioxideoccurs and quinaldine-3-carboxylic acid is formed almost quant'i-tatively. In a similar manner 2-n-amylquinoline may be obtainedfrom hexoylacetic acid and o-aminobenzaldehyde.The isoquinoliiie group of alkaloids is exceedingly rich in itsvariety of examples and no one who surveys the different types canfail to be convinced that they owe their biogenetic origin to theunits suggested by Winterstein and Trier.The four main groupsare the papaverine group (I), the berberine group (11), the phenan-thripyridine group (111), and the morphine group (IV).NMeRO (111.)The units in papaverine and the phenanthripyridine groupare 3 : 4-dihydroxyphenylethylamine and 3 : 4-dihydroxyphenyl-acetaldehyde, the latter giving rise to the benzyl portion of themolecule, and in the berberine group the intervention of formalde-hyde is also necessary.The morphine group, which includessinomenine, also contains these two units, although in the case ofmorphine there is some doubt as to how the ethylamino side-chainarrives on the tertiary carbon atom. One plausible explanation ha180 ORGANIC CHEMISTRY.-PART III.been given by R. Robinson and S. Suga~awa.~ Morphine, however,is accompanied in opium by over 22 other alkaloids, the majority ofwhich are clearly framed from t’he same two units, so there can beno doubt whatever that morphine has a similar biogenetic origin.It is therefore surprising to find that H. Emde lo regards morphineas having arisen from three molecules of a hexose and one of methyl-amine with loss of carbon dioxide and water, and to visualise thishe postulates a pro-morphine (V) in the plant, which loses carbondioxide.The two intact hexose chains seen in (V) are shown in (VI)in bolder print and it will be at once clear that the scheme, whilstingenious, fails to carry conviction.A synthesis of an isoquinoline alkaloid under biological conditionshas not yet been effected, although a synthesis of tetrahydropa-paverine in 8 yo yield from homoveratraldehyde and homoveratryl-amine in the presence of 19% hydrochloric acid and at a water-bathtemperature, based on the Winterstein-Trier mechanism, has beeneffected by E. Spath and F. Berger.llCH, CH,Stereochemistry .An interesting example of spiro-asymmetry has been recorded by(Sir) W.J. Pope and J. B. Whitworth.12 spiro-5 : 5-Dihydantoin(I) has been resolved by crystallisation in alcoholic solution withtwo molecular proportions of brucine. The behaviour is somewhatnovel, for a hot solution of the components deposits a salt of theform 1B,ZA in an almost pure condition and on allowing the filtratelo Naturwiss., 1930, 18, 539; A., 1930, 1072. 9 J . , 1931, 3163; A., 174.11 Ber., 1930, 83, 2098; A., 1930, 1454.12 Proc. Roy. XOC., 1931, [ A ] , 134, 357; A., 171KING. 181to stand an almost pure salt of the form 2B,dA separates. Evidencehas also been obtained pointing to the existence of 3 tautomericforms (I), (11), and (111), for when the hydantoin (I) with similarNHCO NH.70 NH*CO>c(NH*$OH fJ*CO NH*R*OH(50-NH%O*NH do*m CO-N HO*C*NH%O*N(1.) (11.) (111.)rotations in alcohol, water, and pyridine is dissolved in one molecularproportion of sodium hydroxide solution the rotation falls to aboutone-half its value through formation of the keto-enolic form.When(I) is dissolved in two or more molecular proportions of alkali, thesolution is temporarily stable and shows a change of sign of rotationthrough formation of a di-enolic form. Incidentally the usefulnessof brucine for forming salts with hydantoins is thus well establishedand should lead to the direct resolution of hypnotics of the nirvanol,luminal type, examples of which are hitherto unrecorded.12QT. Nishikawa 13 obtained crystalline brucine salts from his a- and @-forms of C-methylbarbituric acid, but failed to resolve either,whilst C.M. Hsueh and C. S. Marvel l4 were unable to isolate stablesalts of alkaloids with ethyl-sec.-butylbarbituric acid.Another contribution l5 from the Cambridge laboratories fulfilsthe prediction made in an earlier paper l6 that quaternary salts of8-substituted derivatives of quinoline should exhibit a moleculardissymmetry which is dependent on restricted rotation about asingle bond. Previously it had been shown that benzenesulphonyl-8-nitronaphthylglycine (IV) could be resolved into dextro- andhvo-modifications and now it has been demonstrated that8-benzenesulphonylethylamino- 1 -ethylquinolinium iodide (V, R =Et) can also exist in optically active forms. In either case the groupon the adjacent peri- or l-position restricts the free rotation of thetrebly substituted nitrogen atom about the bond linking it to thenucleus.See, however, H.Sobotka, M. F. Holzman, and J. Iiahn, J . Amer.Chem. SOC., 1932, 54, 4697.lS Mern. Ryojun Coll. Eng., 1931, 3, 277.l4 J . Amer. Chern. SOC., 1928, 50, 855; A., 1928, 529.l5 W. H. Mills end J. G. Breckenridge, J . , 1932, 2209.W. H. Mills and K. A. C. Elliott, J., 1928, 1291; A . , 1928, 748; Ann.Iieports, 1928, 25, 117182 ORGANIC CHEMISTRY.-PART III.The determination of the configuration of optically activesubstances is an aid to classification, but it often taxes the ingenuityof chemists. There are two methods employed, both of limitedapplication. I n the first and more direct method the change ofrotation is observed in transformations which do not involve re-placements of groups directly attached to the asymmetric carbonatom and where optical inversion is presumably excluded. A classicexample is the demonstration by K.Freudenberg l7 that Z-glycericacid, Z-lactic acid, d-malic acid, and &tartaric acid all possess thesame relative spatial configurations of hydrogen atoms, hydroxyland carboxyl groups attached t o the asymmetric centre. The secondmethod, introduced by G. W. Clough,ls is a less direct one. It isassumed that “ the optical rotatory powers of similarly constitutedcompounds possessing the same configuration are in general in-fluenced similarly by t,he same changes in the external conditionsand also by the introduction of the same substituent into a givenradicle attached to the asymmetric carbon atom.’,Both methods have now been used by W.Leithe19 for a deter-mination of the configuration of coniine and a-pipecoline in terms ofamino-acids which are standards of reference. Willstgtter on theone hand showed that (+)*-conhydrine (VI) by oxidation gavea laevorotatory (-)-pipecolinic acid (VII); on the other hand,K. Loffler and G . Friedrich 2O showed that (+)-conhydrine could beconverted through P-coniceine (VIII) into (-)-coniine (IX), so that(+)-coniine corresponded in configuration t o (+)-pipecolinic acid.This acid, however, by an application of Clough’s principles has been17 Ber., 1914, 47, 2027; A., 1914, i, 924.18 J . , 1918, 113, 526; A., 1918, ii, 255.20 Ibid., 1909, 42, 107; A., 1909, i, 180.* (+) and (-) indicate the observed signs of rotation of the materiaIsCompare A. Wohl and K. Freudenberg, Ber., 1923, 50,lD Ber., 1933, 05, 927; A., 865.under discussion.309; A., 1923, i, 182KING. 183shown to belong to the d-series of amino-acids. (+)-Pipecoline(Zmethylpiperidine) is also spatially related to (+)-coniine, as isshown by the analogous optical behaviour of the bases in solventsand as salts, so that (+)-coniine, (+)-pipecoline, and (+)-pipe-colinic acid belong stereochemically to the d-series of amino-acids.In a somewhat similar manner W. Leithe 21 has been able todetermine the configuration of a-phenylethylamine and of bases ofthe type of laudanosine and tetrahydroberberine.When (-)-a-phenylethylamine (X) is benzoylated and the benzoyl product madesusceptible to oxidation by introduction of a hydroxyl group in theplienyl nucleus, it can be oxidised to E( +)-benzoylalanine identicalwith that prepared from natural l( +)-alanine. (-)-a-Phenylethyl-amine has therefore the Z-configuration. Now bases of the laudan-osine and tetrahydroberberine type may be regarded as substituteda-phenylethylamines, as the following formulze (X-XIII) show.I CH2Ph(XIII.)On this basis Leithe, using Clough’s principles, has shown thatE( -)-phenylethylamine (X), its N-ethyl derivative (XI), (-)-1-methyltetrahydroisoquinolhe (XII), (- )-protolaudanosine (XIII),and ( - )-tetrahydroprotoberberine are all configurationally similarand thus belong to the Z-alanine series.During the past year two attempts have been made to classifythe complex stereochemical system of cinchona alkaloids withtheir four asymmetric centres.22 Consideration of cases of resolutionof such substances as l-methylcyclohexylideneacetic acid of Pope,Perkin, and Wallach, where there is no asymmetric carbon atom,raises doubts as to the legitimacy of attributing particular signs ofrotation to asymmetric centres in such substances as the cinchonaalkaloids.The results obtained, however, when accepted withreserve do seem to justify the means adopted. P. Rabe 23 with awealth of experimental material accumulated over a span of yearshas followed the methods used by H. King and A. D. Palmer 24 indeducing the sign of the contribution of the asymmetric centres in21 Ber., 1931, 64, 2827; A,., 177.22 Cornpare J.Keriner, Ann. Reports, 1022, 19, 157.23 Annalen, 1932, 492, 242 ; A., 289. 84 J., 1922, 121, 2677184 ORGANIC CHEMISTRY.-PART 111.these alkaloids, arrives at the same conclusions, and has beenable to classify sixteen closely related alkaloids. The principlesinvolved are briefly these. The cinchona alkaloids of generalformula (XIV) all give rise to weakly rotatory “ toxines ” (XV),N--CH( OH)---(4)(XIV.)the same “ toxine ” being obtainable from four stereoisomericalcohols (XIV). Thus hydrocinchonine, hydrocinchonidine,epihydrocinchonine, and epihydrocinchonidine, where R = H,R’ = Et, a 1 give rise t o the same hydrocinchotoxine, so that t,he(XV.) AH’differences between the alkaloids must lie in the spatial arrangementaround carbon atoms 3 and 4.Hydrocinchonine and epihydro-cinchonine give rise by two different experimental methods t o thesame highly dextrorotatory deoxyhydrocinchonine, where -CH(OH)-has been replaced by -CH,- just as hydrocinchonidine and epihydro-cinchonidine give rise to an isomeric deoxyhydrocinchonidine oflaworotation. The assumption is therefore made that the asym-metric carbon atom 3 is dextrorotatory in its contribution in theformer pair of alcohols and lzevorotatory in the latter pair. Hydro-cinchonine and epihydrocinchonine can thus only differ in thearrangement around carbon atom 4, and the same applies tohydrocinchonidine and epihydrocinchonidine. Another assumptionis now necessary.It i s assumed that, since hydrocinchonine hasa high dextrorotation and epihydrocinchonine a low dextrorotation,carbon atom 4 is dextrorotatory in its contribution in hydro-cinchonine and hvorotatory in its contribution in epihydro-cinchonine ; similarly, since epihydrocinchonidine has a dextro-rotation and hydrocinchonidine a laevorotation, carbon atom 4 isdextrorotatory in the former and lzevorotatory in the latter. Thesame reasoning has been applied by Rabe and his pupils to sixteen oKING. 185these closely related bases, all of the general formula (XIV), with thefollowing results.Optical sign of Optical sign ofc3. c4. c3. c4.R = OMe; R’ = CHXH,. R = OMe; R’ = Et.- - Hydroquinine ............ - -...............epiHydroquinine ...... - + + epiQuinine -epiQuinidine ............... + - ......Quinidine Hydroquinidine ......... + + .................. + -t- - Hydrocinchonidine ...... _ -epicinchonidine ......... - + epiHydrocinchonidine - -tepicinchonine ............ -t- - epiHydrocinchonine ... + -Cinchonine Hydrocinchonine ...... + +Quinine ..................epiHydroquinidine + -R = H; R‘ = CHZCH,. R = H; R’ = Et.Cinchonidine ........................... + +It will be noted that in the eight common naturally-occurringalkaloids the sign of rotation attributed to carbon atom 3 is alwaysthe same as that of carbon atom 4. In further just’ification of thissystem of classification it may be pointed out that the same resultfor the eight common alkaloids may be arrived at from a consider-ation of the magnitude of the specific rotations alone of the fourisomeric bases in any one group ; quinine and quinidine, for example,have the highest and the lowest lzevo- and dextro-rotations respec-tively of the four isomerides.P.Rabe and S. Riza25 have extended the results to the fourstereoisomeric rubanols (XIV ; R = R’ = H), obtained by syntheticmethods, in which carbon atom 1 has lost its asymmetry, andhave again obtained concordant results.A dserent view is adopted by H. Emde26 but on a less satis-factory basis. He invokes the principle of optical superposition ina form used by Hudson and then abandons its legitimate deductions.Cinchona alkaloids only occur in nature in two out of the possiblesixteen optically active forms and since, according to Emde, allexamples of epimerism among naturally occurring substances are dueto secondary carbinol groups, this must be the case in the cinchonaalkaloids.The asymmetric centre 3 must therefore have the sameconfiguration in all the naturally occurring alkaloids and the observedisomerism must be entirely dependent on the spatial arrangementaround carbon atom 4. On such a basis it is difficult to see howEmde would approach the problem of the configuration of carbonatoms 3 and 4 in the epimeric bases.Dipole measurements have been invoked2’ in determining thespatial- arrangements around the sulphur atoms in thianthren25 Anmlen, 1932, 496, 151 ; A., 865.26 Helv.Chim. Acta, 1932, 15, 557; A., 759.27 E. Bergmann end M. Tschudnowsky, Ber., 1932, 65, 458; A., 507186 ORGANIC CHEMISTRY .-PART III.(XVI) and the two isomeric disulphoxides (XVII) and (XVIII) withdipole moments respectively of 1.68, 1-7, and 4.2.(2x1.) (XVII.) (XVIII.)Thianthren cannot be planar and it is supposed that the moleculeis slightly folded at the sulphur atoms. The disulphoxide of struc-ture (XVII) has practically the same dipole moment as thianthren,since the moments of the SO groups compensate one another. I n(XVIII), however, the SO groups reinforce one another. It naturallyfollows that the oxygen atoms cannot be in the same plane as the CSbonds. A similar conclusion has of course already been reachedthrough the resolution of sulphoxides by Phillips and Kenyon. TheGerman workers are, however, loth to accept the postulate of semi-polar double bonds as an explanation of the phenomena, as in theiropinion the formation of a decet of electrons around the sulphuratom is not excluded.Oxide Rings in NaturaE Products.Fish Poisons.-This group of natural poisons has attractedconsiderable attention during recent years through the need forefficient insecticides.An arrow poison used by the Malays underthe name Ipoh is said t o be obtained from Derris elliptica (Fam.Leguminosm), known to the Javanese as tuba root and employed bythem as a fish poison. The active principle, tubatoxin, was firstisolated by T. Ishikawa 28 and later shown by T. Kariyone, K.Atsumi, and 11.Shimada 29 to be identical with rotenone, firstlisolated by K. Nagai 3O from Millettia taiwaniana Hayafn, obtainedfrom Formosa.Through the efforts of the chemists of four different nations theconstitution of rotenone is now agreed to be (I). On gentle oxidationit readily loses two hydrogen atoms with formation of dehydro-rotenone 31 (11). The latter substance can be saponified by alcoholicpotassium hydroxide with formation of derrisic acid (III), withaddition of two molecules of water, from which dehydrorotenone (TI)28 Jap. M e d . Lit., 1917, 1, 7 ; A., 1918, i, 94.29 J . Pharm. SOC. Japan, 1923, 500, 739; A . , 1924, i, 950.30 J . Tokyo Chem. Soc., 1902, 23, 744.31 A. Bntenantlt, Aw)zcrlc>i, 1928, 464, 2 5 3 ; A . , 1928, 1017KING.187is re-formed by the action of acetic anhydride,32 possibly throughformation of an intermediate lactone.Me0(11.1CH, 0CH,-CH*CMe:CH,Me0(111.)The molecule of derrisic acid is seen to be built up of two benzenenuclei with various addenda. When oxidised with hydrogenperoxide, derrisic acid yields derric acid33 (IV), and on furtheroxidation with permanganate this gives the lower homologue,risk wid (V), which can be decarboxylated to decarboxyrisic acidMe0()0*CH2*C02W g 8 3 0 * & 2 * 8 0 2 H CH COH Me0 MeO()O*CH,*C02H CO,H Me0(IV.) (V.) (VI.)The constitutions deduced for these acids by LaForge have sincebeen confirmed by syntheses of derric acid and risic acid by A.Robertson,35 of risic acid by S. Takei, S. Miyajima, and M.O ~ O , ~ ~and of decarboxyrisic acid by LaF~rge.~'The determination of the constitution of the second half of themolecule of rotenone proved to be a more difficult problem. By32 F. B. LaForge and H. L. Haller, J . Ainer. Chem. SOC., 1932, 54, 813;A., 401.33 F. B. LaForge, ibid., 1931, 53, 3896; A., 1931, 1415.s4 F. B. LaForge and L. E. Smith, J . Amer. Chem. SOC., 1930, 52, 2878(VI) *A., 1930, 1187; S. Takei, S. Miyajima, and M. Ono, Ber., 1931, 64, 248;A., 1931, 490.3 5 J., 1932, 1380; A., 751.37 J . Amer. Chem. SOC., 1931, 53, 3896; A., 1931, 1415.36 Ber., 1932, 65, 1041 ; A., 860188 ORGANIC CHEMISTRY.-PART IT”.the action of alcoholic potassium hydroxide on rotenone S. Takei 38had obtained an acid called tuhaic acid, now known to be C,,H1,04.39The constitution of tubaic acid (VII) was finally proved by H.L.Haller and F. B. LaForge40 by a close study of its properties,although much supplementary experimental evidence was suppliedby S. Takei and his co-~orkers.~l Tubaic acid was optically activeand contained a hydroxyl group, an indifferent oxygen atom, anda double bond which could readily be reduced, yielding dihydro-tubaic acid. On further hydrogenation it gave tetrahydrotubaicacid (VIII) , which could be decarboxylatecl to 24soamylresorcinol(IW‘CH2dH*CMe:CH2 hH,*CH,-CHMe, hH,*CH,*CHMe,(VII.) (VIII.) (IX.)The orientation of groups in (IX) is established, since it is knownthat alkyl groups meta to hydroxyl groups inhibit the fluoresceintest and one of the hydroxyl groups in (VIII) is indifferent tomethylating agencies.The loss of optical activity observed when(VII) is converted into (VIII) shows that the isopropenyl side-chain is attached as shown and not t o the neighbouring carbonatom.The constitutions of the two halves of the rotenone moleculehaving been determined with a considerable degree of certainty,a satisfactory formula (I) was suggested almost simultaneously byF. B. LaPorge and H. L. Haller,42 by A. Robertson,43 by S. Takei,X. Miyajima, and M. O ~ O , ~ ~ and by A. Rutenandt and W.M~Cartney.~~The numerous degradation products have almost all been assignedconstitutions which in some cases have been confirmed by elegantpartial syntheses. Thus, when rotenone is treated with zinc dustand alkali, it yields derritol46 (X) with a loss of two carbon atoms.The properties of this substance are consistent with the structureshown, for when treated with ethyl chloroacetate it yields derrisic38 J .Chem. SOC. Japan, 1923, 44, 841; Biochem. Z., 1925, 157, 1; A . ,39 T. Kariyone and S. Kondo, J . Pharm. SOC. Japan, 1925, 518, 376.40 J. Amer. Chem. SOC., 1931, 53, 4461; 1932, 54, 1988; A . , 165, 739.41 Ber., 1928, 61, 1103; 1929, 62, 3030; A., 1928, 765; 1930, 216.42 J . Arner. Chem. SOC., 1932, 54, 810; A., 401.43 J., 1932, 1380; A., 751.45 Annalen, 1932, 494, 17 ; A., 619.4 6 A. Butenandt, ibid., 1928, ‘464, 259; A . , 1928, 1017.1925, i, 761.44 Ber., 1933, 65, 1044; A., 860KING. 189acid (111) mixed with dehydrorotenone 47 (11).The constitutionof rotenonone, a product of strong oxidation of dehydrorotenoneMe0and differing from it by the substitution of an oxygen atom fortwo hydrogen atoms, has been finally solved by the observationthat rotenonone is hydrolysed almost quantitatively by alcoholicpotassium hydroxide into derritol (X) and oxalic acid.47 Con-versely, rotenonone has been synthesised from derritol (X) andethyl oxalate or chloro-oxalyl ethyl ester, so its constitution mustbe that represented by 48In the practical application of 'derris extracts as insecticides itwas observed by American workers that extracts poor in rotenonecould be very active insecticides. E. P. Clark, following up theclue, showed that derris roots also contained toxicarol, deguelin,and tephr0sin,4~ the first two of which a t a dilution of 1 in 5 x lo6will kill goldfish in 3 or 4 hours.Clark was also able to show thatcube', a Peruvian fish poison, contained rotenone, tephrosin, anddeguelin and that Tephrosia toxicaria from British Guiana containedtoxicarol and d e g ~ e l i n , ~ ~ whilst T . vogelii from Africa and Sumatracontained tephrosin and deguelin,51 an observation made indepen-dently by A. Butenandt and G. Hilgetag.52There is a close similarity in the molecular formulze of thesesubstances, suggesting a phytochemical relationship. Such is thecase, for E. P. Clark has shown that all three substances give thesame derric and risic acids as were obtained from rotenone.53 Theconstitution of deguelin (XII) has been determined by Clark.54474 849505152sa54S.Takei, S. Miyajima, and M. Ono, Ber., 1932, 65, 1043; A., 860.F. B. LaForge, J . Amer. Chem. SOC., 1932, 54, 3377; A., 1039.Science, 1930, 71, 396; A., 1930, 967.J . Amer. Chm. Soc., 1930, 52, 2461; A., 1930, 1223.Ibid., 1931, 53, 729; A., 1931, 491.Annalen, 1932, 495, 172; A., 751.J . Amer. Chern. SOC., 1932, 54, 1600; A., 619.Ibid., p. 3002; A., 950190 ORGANIC CHEMISTRY.-PART III.It passes on gentle oxidation with loss of two hydrogen atoms intodehydrodeguelin, which is also obtained by dehydration with aceticMe0 Me0(XII.) (XIII.)anhydride of tephrosin (XIII) and is~tephrosin.~~ In these twosubstances the relative positions of the added elements of the watermolecule are undecided.Dehydrodeguelin, which is optically in-active, on oxidation with permanganate yields a new tricarboxylicacid, nicouic acid, C,,H,,O,, which at its melting point losesa-hydroxyisobutyric acid. As it also gives the fluorescein reactionfor resorcinol and yields the latter on boiling with aniline, theconstitution (XIV) is assigned to it.Furthermore, when rotenone is reduced catalytically, it givestogether with other products a so-called rotenonic acid 56 (XV),which was shown by H. L. Haller 57 to isomerise under the influenceof acetic and sulphuric acids into P-dihydrorotenone (XVI) isomericwith dih ydrorotenone. p -Dihydrorot enone on gentle oxidationgave dehydro-P-dihydrorotenone, which proved to be identical withdihydrodehydrodeguelin obtained by Clark by catalytic reductionof dehydrodeguelin .Me0 Me0These observations prove conclusively that the oxide ring inthe second half of the molecule is a six-membered ring as shown.The same constitutions for deguelin and tephrosin on the basis ofClark's experimental results have also been advanced by A.Robert-55 E. P. Clerk and H. V. Claborn, J . Amer. Chem. Soc., 1932, 54, 4455.G6 F. B. LaE'orgc aiicl L. E. Smith, ibid., 1929, 51, 2574; A., 1181.o 7 Idem, ibid., 1931, 53, 733; A., 1931, 491KING. 191son 58 and by A. Butenandt and H. Hilgetag.59 The constitutionof toxicarol is still unsettled, the formulm proposed by Clark andby Butenandt and Hilgetag 59 showing considerable difference.From the solution of the constitution of these fish poisons andinsecticides arises the interesting and practical question as to thesimplest structure which retains these properties.Peucedanin, abitter principle from Peucehnurn oficinale, is known to be it fishpoison and recently 60b its constitution has been elucidated as(XVII). Still simpler structures but of the same type are pos-sessed by bergapten (XVIII) and xanthotoxin (XIX), which arealso known to be fish poisons.6lCH Me0 CHCHCunnabinol.-A resinous secretion of Indian hemp (CannabisIdicu) is known as hashish or bhang and has been used as anintoxicating drug for centuries in the East. By fractional dis-tillation of the resin, T. B. Wood, W. T. N. Spivey, and T. H.Easterfield 62 were able to isolate a series of substances, one ofwhich, a high-boiling oil, they concluded to be the active principle.Cannabinol is a constituent of this oil and is isolated as its crystallineacetyl derivative.On oxidation of the active fraction with nitricacid, nitrocannabiiiolactone, CI,HllO,N, was obtained, from whichcannabinolactone, C11H,202, was isolated by removal of the nitro-group. Cannabinolactone gave m-toluic acid on fusion withpotassium hydroxide. The constitution of cannabinolactone hasnow been definitely determined by R. S. Cahn63 and confirmedby F. Bergel and K. Vogele 64 by synthesis. Cahn found that5* J., 1932, 1384; A., 751.6o J. Amer. Chem. SOC., 1932, 54, 2537; A . , 855.60a Trier, “ Chem. d. Pflanzenstoffe,” 1924, 268.608 E. Spiith, K.Klager, and C . Schlosser, Ber., 1931, 64, 2203; A., 1931,61 C. Pomeranz, Monatsh., 1893, 14, 29; H. Thoms and E. Baetcke, Ber.,62 J . , 1899, 75, 20.63 J . , 1930, 986; 1931, 630; 1932, 1342; A . , 1930, 913; 1931, 625; 1932,64 Annalen, 1932, 493, 250; A . , 382.59 Annalen, 1932, 495, 172; A , , 761.1298.1912, 45, 3705; A., 1913, i, 192.747192 ORGANIC CHEMISTRY .--PART 111.nitrocannabinolactone could be converted into the correspondinghydroxycannabinolactone, which on fusion with potassium hydr-oxide gave 6-hydroxy-m-toluic acid (I), identical with the syntheticmaterial, and acetone. Wood, Spivey, and Easterfield were alsoable to oxidise cannabinolactone to cannabinolactonic acid (11),which Cahn has shown to be further oxidised to trimellitic acid,Me CO,H Me Mebenzene-1 : 2 : 4-tricarboxylic acid, whence it follows that canna-binolactone must be represented by (111).The synthesis by F.Bergel and K. Vogele G4 starts from p-cymene-3-carboxylic acid(IV), which is oxidised by chromic acid to cannabinolactone (111)and other products. On further oxidation of the synthetic materialwith alkaline permanganate cannabinolactonic acid (11) was pro-duced identical with a product obtained by G. Bargellini andG. Forli-Forti 65 from 4-aminodimethylphthalide 63 and also identicalwith an acid obtained from santonin by Cannizzaro and Gucci.The constitution of cannabinol has not been determined withcertainty, but sufficient is known to make the constitution (V)possible.63 Cannabinol can be acetylated, forms a methyl ether,and can be oxidised to n-hexoic acid, a product previously reportedby earlier observers as being obtainable from crude high-boilingcannabis resins.The positions assigned to the hydroxyl and then-amyl group are in accord with the products of oxidation andnitration and with the observation that cannabinol does not reactwith diazomethane in ethereal solution and does not dissolve insodium hydroxide solution.Simple Furan Derivatives.-Y. Asahina and collaborators 66showed that elsholtxione, a ketone obtained from the essential oil6 5 Gazzettu, 1910, 40, ii, 74; A . , 1910, i, 744.66 Arch. Pharm., 1914, 252, 435; A., 1915, i, 429; J . Pimrm. SOC. Japan,1922, 485, 565; A., 1922, i, 1047 ; Acta Phytochim., 1924, 2, 1 ; &4., 19334, i,976KING.193of Elsholtzia cristata, Willdenow, was almost certainly 3-methyl-2-fury1 isobutyl ketone (I).Me -Me -Me -I' IICO*CH2*CHMe, II I1CO2H I1 llCN Y (11.) Y (111.) v 0 (1.)This has been confirmed by its synthesis 67 from p-methylfuran,which by Gattermann's method gave 3-methylfurfuraldehyde andthis on oxidation gave elsholtzic acid (11) identical with an acidobtained from elsholtzione by Asahina. 3-Methylfurfuraldehydewas converted through its oxime into the nitrile (111), and asynthesis of elsholtzione (I) effected by allowing the nitrile toreact with isobutylmagnesium bromide.6'T. Reichstein and H. Zschokke 68 have also synthesised furan-(3-carboxylic acid in two ways and have shown that it is identicalwith the naturally occurring furan- p-carboxylic acid isolated byH.Rogerson from Euonymus atropu~pureus.~~ The synthesis ineach case depends on the partial decarboxylation of furandicarb-oxylic acids (IV) and (V) with loss of the carboxyl group in thea-position. The former dicarboxylic acid was obtained by F.Feist 70 by the action of potassium hydroxide on methyl bromo-coumalate (VI). The second synthesis depends on the intermediate,OH 0, q C o r -3 C02€€*C\~C*C0,H GH PH -+ CO,H.C!.JICH CH/\C-CO,HC02Me*C1!,&B(VL) CHsynthesis of the diethyl ester of 3-carboxyfuryl-%acetic acid (VII)by condensation of chloroacetaldehyde and ethyl acetonedicarb-oxylate. This ester on saponification and decarboxylation gaveQHO yH,*CO,R C0,R -CO,HCH, CO*CH,*C02R + It IIc~,.co~R + II ltMe\Cl Y (VII.) \/ (VIII.)2-methylfuran-3-carboxylic acid (VIII), which could be oxidisedto furan-2 : 3-dicarboxylic acid.67 T.Reichstein, H. Zschokke, and A. Goerg, Helv. Chim. A N , 1931, 14,1277; A., 166.68 Ibid., 1932, 15, 268; A., 519.70 Ber., 1901, 54, 1992; A., 1901, 657.69 J., 1912, 101, 1044.REP.-VOL. X-. 194 ORGANIC CHEMISTRY.-PART III.Anthocyanins.-The past year has witnessed the culminatingpoint in the chemistry of the anthocyanins. R. Robinson andA. R. Todd ‘1 have succeeded in synthesising the five diglucosidesknown as hirsutin, malvin, pelargonin, peonin, and cyanin chlor-ides, identical with the products from natural sources. All proveto be p-diglucosides substituted in the 3- and the 5-position of theanthocyanidin nucleus.Great experimental difficulties had to beovercome in the preparation of the intermediates, which whenonce obtained were condensed in the usual manner, of which thesynthesis of pelargonin may be taken as a typical example. 2-0-Monoacetyl- p-glucosidylphloroglucinaldehyde (I) and a-O-tetra-acetyl-~-glucosidoxy-4-acetoxyacetophenone (11) were condensedin dry ethyl acetate by hydrogen chloride. The resulting flavyliumsalt (111) was kept in alkali in a hydrogen atmosphere t o removeacetyl groups and acidified. Pelargonin chloride (IV) then separatedin a state of purity.c1 c1P+ +-IH O e o H H o d e o A c0 C6H1105 $) C6Hi’0(0Ac)4b6H1105 (Iv.) C6H,,O,*OAc (111.)c1H o d - 6 OH OH (V.)5)C6H 1 lo 5In a similar manner, by use of the appropriate initial materialscyanenin chloride (V) and malvenin chloride, the partial hydrolyticproducts of cyanin and malvin chlorides have been synthesised.72If confirmation were needed of the view that malvin is a digluco-side containing the glucose residues attached to different hydroxyl7 1 J., 1932, 2293, 2299, 2488; A., 1140.72 A. Le6n and R. Robinson, J . , 1932, 2221; A., 1038"NQ. 195groups, such has been furnished by P. Karrer and G. de Me~ron.'~Karrer and his collaborators had previously 74 shown that antho-cyanins could be oxidised by hydrogen peroxide and that in twocases it was possible to isolate crystalline intermediate products,malvone and hirsutone, from malvin and hirsutin respectively.A re-investigation of malvone and hirsutone by Karrer and deMeuron has demonstrated that these ketones readily give a quanti-tative yield of syringic acid and glucose by solution in 2N-sodiumhydroxide a t room temperature.If treated with phenylhydrazine,they readily give up one molecule of glucose as phenylhydrazoneand on acid hydrolysis of the residue the remaining glucose groupmay be found. For this reason malvone (VI ; R = H) and hirsutone(VI ; R = Me) are now regarded as esters of glucose and of syringicacid, with glucose attached to different parts of t,he molecule.n OMeBy application of the phenylhydrazine test to the solutions con-taining the hydrogen peroxide oxidation products of peonin, cyanin,and monardin it has been demonstrated that these three antho-cyanins also contain two glucose groups in different positions inthe molecule and one of them must be attached to position 3, aconclusion in agreement with the syntheses of Robinson and Todd.Nitrogenous .Anthocyanins.-In 1918 R. Willstatter and G.Schudelshowed how many pigments, rosaniline, methylene-blue, and others,could be removed from aqueous solution by extraction with anorganic solvent containing picric or dichloropicric acid.75 Thistechnique was applied by Schudel 76 to the colouring matter ofbeetroot (Beta vulgaris) and resulted in the isolation of an unstablenitrogenous diglucosidic anthocyanin, named betanin chloride,which gave betanidin chloride on hydrolysis. Similar pigmentswere found in Celosia cristata and in winter-spinach (Atriplexhortensis atrosanguineus) .On the synthetic side L.R. Ridgway and R. Robinson 77 hadprepared 3-carbethoxyamino-4'-methoxy-8-ethoxy-2-phenylbenzo-pyrylium chloride (VII) from 2-hydroxy-3-ethoxybenzaldehyde anda-carbethoxyamino-p-methoxyacetophenone, but attempts to obtain73 Helv. Chim. Act&, 1932, 15, 507, 1212; A., 520.74 Ibid., 1927,10, 729; A., 1927, 1197.75 Ber., 1918, 51, 782; A., 1918, i, 399.7 7 J., 1924, 125, 2240; A., 1925, i, 54.'~3 Dissert., Ziiricli196 ORGANIC CHEMISTRY .-PART III.the 3-aminoflavylium salt were unsuccessful, the amino-groupbeing replaced by hydroxyl. R. Robinson and (Mrs.) A. M. Robin-c1FO*C,H,*OMe - HO CH,*NH*CO,Etson 78 have now succeeded in preparing pure 4'-aminoflavyliumperchlorates (VIII) and (IX) by use of 4-aminoacetophenones.c10,.-%c10,+-l(VIII.) (IX.)It is of interest that in these substances the amino-group is abetter auxochrome than hydrosyl, and with this may be coupledthe observation that betanidin is the bluest-red of all the antho-cyanidins.The authors regard it as possible that the dihydroxy-aminoflavylium salt (IX; R = H) may be identical with betanidin,since the colour reactions and the absorption spectra, in the visibleregion, of extracts of beet and atriplex in 0.1% hydrochloric acidand of 4'-amino-3 : 7-dihydroxyflavylium chloride showed closecorrespondence. Later unpublished work would, however, seemto suggest a possibility of betanidin being identical with a trihydroxy-flavylium salt.79A1 kuloids.Derivatives of I%doZe.-The developments in alkaloidal chemistrywithin the last few years have shown that there are a number ofalkaloids containing the indole nucleus, derived presumably fromtryptophan. The constitution of very few of these alkaloids isknown with certainty ; exceptions are physostigmine and theharmine group. The following account is confined to the moreimportant developments in this field.Ergot AZEaZoids.-It may be recalled that for a number of yearsergotoxine and ergotinine were the only two definitely recognisedalkaloids of ergot. In 1922 A. Stoll 8o isolated a second pair ofisomeric alkaloids, ergotamine and ergotaminine, which chemicallyand pharmacologically show very close similarities to the formerpair of alkaloids.S. Smith and G. M. Timmis 81 were able to78 J., 1932, 1439; A., 750.61 J . , 1930, 1393; 1031, 1888; .4., 1930, 1050; 1931, 1171.78 Naturwiss., 1932, 33, 613.Schtoei;.. Apoth.-Ztg., 1922, 60, 341; A., 1923, i, 137RING. 197confirm the isolation of ergotamine and ergotaminine but onlyfrom unofficial ergots, such as that growing on a New ZealandPesturn. In 1931 the same observers showed that ergotoxine wasaccompanied by two alkaloids, ergotinine and +-ergotinine, theproportion varying in different ergots. Both ergotinine and $-ergo-tinine are converted into ergotoxine by boiling with alcohol" andphosphoric acid and +-ergotinine is partly converted into ergotinineby boiling with methyl alcohol. The composition of these alkaloidsis still doubtful.A. Soltys 82 gives good reasons for concludingthat ergotamine and ergotaminine may be represented by theformula C,3H350,N5 and ergotinine by C35H3905NS. He also findsall four alkaloids to be phenolic or weakly carboxylic, to yieldammonia on hydrolysis, and to give benzoic acid on oxidationwith permanganate and p-nitrobenzoic acid on oxidation withnitric acid. W. A. Jacobs 83 confirms the latter observation onergotinine and has isolated a new base, C,,H908N, containing threecarboxyl groups and one N-methyl group by the action of nitricacid. On the other hand, Smith and Timmis 84 have shown thatall four alkaloids on hydrolysis with alcoholic potassium hydroxidegive ammonia and a base ergine, Cl,Rz1ON3, which likewise con-tains one N-methyl group and gives many colour reactions associ-ated with indole derivatives.The only other important observationbearing on the constitution of these alkaloids is the well-knownone of G. Barger and A. J. E w i n ~ , ~ ~ that ergotoxine and ergotininegive isobutyrylformamide, CHMe,*CO-CO*NH,, on heating. Thisis probably the amide group present in the molecule of these alkaloidswhich appears as ammonia on hydrolysis.Physoatigmine.-The pioneering experimental work of G. Bargerand E. StedmanS6 and of M. and M. Polonowski*' led to theelucidation of the structure (I) now accepted for physostigmine(eserine). The greatest difficulty in the synthesis of such a structuremight be anticipated in the closure of p-substituted dihydroindolesMewith formation of the third ring.MeThis has, however, been accom-plished by three different methods which have led to the synthesis82 Ber., 1932, 65, 553; A., 629.83 J .Biol. Chem., 1932, 97, 739; A., 1147.84 J., 1932, 763, 1543; A., 526, 759.8 6 J . , 1925,127, 247; A., 1925, i, 392.87 Compt. rend., 1924,178, 2078; 179, 334; A . , 1924, i, 1094.J., 1910, 97, 290198 ORGANIC CHEMISTRY .-PART III.of structures related to or identical with those of physostigminederivatives.T. Hoshino and K. Tamura 88 allowed p-indolylethylamine t oreact with excess of methylmagnesium iodide (4 mols.) and treatedthe product with methyl iodide. A 30% yield of dinordeoxy-eseroline (11) was thus obtained.R. Robinson and H. S u g i n ~ m e , ~ ~after preliminary syntheses of indolenine derivatives, have beenable t o prepare dl-noreserethole (111) in an instructive manner.Me-l--FH2 EtO --~MeCH2*CH,*N(CO)C,H, co\/C*CO,E tN (IV.)(111.1 EtOO\/?/cB, NMeNH 0Ethyl 8-phthalimido-a-acetyl-8-methylvalerate was coupled withp-etlioxydiazonium chloride in alkaline solution to yield ethyl8 -phthalimido - a - keto - 8-methylvalerate-p-ethoxyphenylhydrazone,C,H4: (CO),:N-CH,*CH,.CHMe*C (C0,Et) :N,H*C ,H,*OE t , with loss ofan acetyl group. When this hydrazone was submitted to the actionof ethyl-alcoholic hydrogen chloride it gave ethyl 5-ethoxy-3-methyl-3- p -pht halimidoet hylindolenine-2 -carboxylat e (IV) . Saponiikationof this by ethyl-alcoholic potassium hydroxide gave a dicarboxylicacid (V) which on decarboxylation in boiling xylene gave theEt O~~~~;Y*CH~-~H yo (V.)N C,H,*CO,Hindolenine (VI).The methosulphate (VII) of (VI) was deprived ofthe phthalic acid by short boiling with hydrazine hydrate in alcoholicsolution and on acidification cyclisation took place by simpleaddition of the amino-group in the side chain to the unsaturatedindoleninium system with production of dl-noreserethole (VIII) .(VII.) (VIII.)As two asymmetric centres are produced, a mixture of two racematesmight be expected; but only one has been observed.8 3 Proc. Imp. Acad. Tokyo, 1932, 8, 171; A., 952.89 J., 1932, 304; A., 287Irma. 199Yet another method for closing the third ring has been workedout by F.E. King and R. Robinson.90 In a preliminary researchH. S. Boyd-Barrett and R. Robinson 91 were able t o prepare deseth-oxydehydroeseretholemethine (IX) by synthesising the indole (X)from y-phenoxypropyl methyl ketone phenylhydrazone. This**CH,*CH,*OPh(IX-) b e NR (X.)~ ~ e e * C H 2 * C H 2 * N M e 2indole was methylated under pressure with methyl iodide to yield1 : 2 : 3-trimethyl-3-p-phenoxyethylindoleninium iodide (XI), thebase corresponding to which on oxidation with permanganate gaveO--xgFCH2*OPh o G g e * C H 2 * C H ,* OP hNMe (XI-) NMe (XII.)an indolinone (XII). By the action of fuming hydrobromic acidthis indolinone was converted into a reactive bromoethyl derivative(XIII ; R = H), the bromine of which could be replaced by methyl-amino- or dimethylamino-groups with production in the latter caseof desethoxydehydroeseretholemethine (XIV ; R = H).QG~~*CH,*CH,B~ + R(&+wCH,*CH2*NMe2By extending the synthesis to the corresponding methoxy-derivative (XIV; R = OMe), King and Robinson were able tosynt hesise and eventually resolve dehydroesermetholemethine,(XIV ; R = OMe) into its optical isomerides, as the quaternary salt.One of these proved to be identical with the natural product, andincidentally the interpretation given to the various stages in thesyntheses received confirmation. Cyclisation of ethylaminoin-dolinones was fmally effected in a simple manner. The methoxy-NMe (XIII.) NMe (XIV.)MeO@$lMe-CH,*CH2*NH2 MeO(J-?-P;g2 2NMe N vo "0(XV.1 (XVI.) Meoo- \/CH\/CH2 (XVII .p5e--p32NMe NHbromide (XIII ; R=OMe) was converted through its reactionproduct with phthalimide into the corresponding ethylamine (XV)90 J ., 1932, 1433; A., 759. O1 Ibid., p. 317; A., 287200 ORGANIC CHEMISTRY .-PART III.which was dehydrated by phosphoric acid in boiling xylene to forman amidine (XVI), and this on catalytic reduction gave noreser-methole (XVII). The latter was characterised as a crystallinequaternary salt, dl-esermet hole methopicrate, which showed a greatsimilarity to the natural salt.There is little doubt that physostigmine is derived in the plantfrom hydroxytryptophan. The possibility, however, of indolenuclei arising by oxidation of amino-acids is shown by the workof H. S. Raper 92 on the conversion of tyrosine and of 3 : 4-dihydroxy-phenylethylmethylamine into indole derivatives under the influenceof tyrosinase.A striking example of the somewhat analogousoxidation of a tertiary base into a quaternary salt by indole ringformation has been discovered by R. Robinson and S. S ~ g a s a w a . ~ ~Laudanosoline (XVIII) is oxidised by chloranil in alcoholic solutionand in the presence of potassium acetate to a dehydrolaudanosolineMe0OH --+OH(XVIII.)hydrochloride, a quaternary dihydroindole (XIX) which containsthe same carbon skeleton as laudanosoline, for on exhaustivemethylation and Emde degradation it gives the same product(XX) as laudanosine itself. Almost the same ground was coveredby C. Schopf and K. Thierfelder,94 who were able to effect thesame dehydrogenation by tetrabromo-o-quinone, by oxygen inpresence of platinum, and by potassium ferricyanide in presenceof a phosphate buffer at pH 6-9-7.1.Strychnos Alkaloids.-During the past year great advances havebeen made in the elucidation of the structural formuh of brucineand strychnine.The advances are such that, although furtherwork is necessary to confirm the internal structure of the molecule,the main features of the outside skeleton may be regarded as settled.The two formulae for brucine (R = OMe) and strychnine (R = H)which find most favour are the following :92 Biochem. J., 1927, 21, 89; A . , 1927, 278. W. L. Dulihre and H. S.Compare also H. Burton, J., Raper, &id., 1930, 24, 239; A., 1930, 814.1932, 546; A., 402.Q3 J., 1932, 789; A., 527.g4 Annalen, 1932,497, 22 ; A., 2046KING.201(I) is that put forward by H. Leuchs 95 and it contains most ofthe features characteristic of the formula advanced by K. N. Menonand R. Robinsong6 except that the bridge from the basic N-atomin the Menon-Robinson formula is attached to the 8-carbon atomof the dihydroindole structure. B. K. Blount and R. Robinsong7prefer the structure (11) in which the bridge C,H, may be inter-preted as GHMe, in which case strychnine would contain theskeleton of tryptophan and also that of harmine. The argumentsin favour of the positions assigned to the bridge are not conclusiveand its final position must await further experimental work.The measure of agreement expressed by these two formula ismainly a result of the interpretationof the experimental observationson the oxidation of these alkaloids with nitric acid, chromic acid,and permanganate.The important product of the oxidation of strychnine with nitricacid, named dinitrostrycholcarboxylic acid by Tafel, has beenshown 96 to be 5 : ,7-dinitroindole-2 : 3-dicarboxylic acid (111).Thisfinds expression in the suggested formulae and is in agreement withQHz-QHz/ \/\CH NQ" Q0\/\ Q0ZHCH CH-0(111.)60 CH (IV.1NH CH, O-CH,the results of E. Spath and H. Brets~hneider,~~ who obtainedN-oxalylanthranilic acid (IV) as a product of the oxidation ofstrychnine with permanganate in alkaline solution, and N-oxalyl-4 : 5-dimethoxyanthranilic acid from brucine. The permanganateoxidation of brucine in acetone solution was the subject of Leuchs'Ber., 1930, 63, 2997; A., 1931, 242.S 5 Ber., 1932, 65, 1230; A., 953.9 7 Ibid., p.2305; A., 1147.O 6 J., 1932, 780; A., 527.6 202 ORGANIC CHEMISTRY .-PART 111.earliest contribution to the chemistry of these alkaloids, but theinterpretation of the results was first correctly advanced by R. C.Fawcett, (the late) W. H. Perkin (jun.), and R. Robinsong9 andhas now been accepted by H. Leuchs and F. Kr0hnke.l Leuchsfound that when brucine, C2,H2,0,N2, was oxidised by permangan-ate, a keto-acid, brucinonic acid (V), was formed which could bereduced by sodium amalgam to brucinolic acid (VI), and this bythe action of alkali gave brucinolone (VII) and glycollic acid.Using formula (I) for simplicity of representation, the changes areas follows :( p 3 2 - p 2CH N/ /\ / \ / \(v’) -7H \;I€ 70 -YH cH co(VI-1 )(\CH/ (VII.) 4 CH CH----CH*OHCO CH 60 CH\/CH2\/\CH, O-CH,The characteristic feature of brucinonic acid (V) is its a-ketonicacid amide group and as such it should be oxidisable by hydrogenperoxide.H. Leuchs and F. Krohnke now k d that such is thecase, for an amino-acid, C,0H2206N2, possibly (VIII), is formed.p 2 - p 2CH NHA further striking degradation has now been re~orded.~ Whenbrucinonic acid (V) or brucinolic acid (VI) is oxidised with chromicacid in sulphuric acid solution, a red crystalline o-quinone (IX) isformed, but the resinous by-products on further oxidation with thesame reagent give a very small yield of an amino-acid, Cl,H,,05N2.The suggestion is made that this is formed by the destruction ofthe truly aromatic portion of the molecule, as happens in thepreparation of Hanssen’s acid, C,,H,,O,N,, from brucine, C,,H,,O,N,,together with loss of glycollic acid and oxidation of the a-ketonic99 J., 1928, 3087; A., 1929, 82.2 Ibid., p.980; A., 866.Ber., 1932, 65, 218; A., 407.Ibid., p. 1230; A., 953KING. 203acid amide group of brucinonic acid as already described.basis the natural result of the degradation is as shown below.On this7H2-(iH2CH NH/ \/\ / \/ R~\-CH YH 70 CO,H.FH YH dH/ \/\ /CH2/cH*co2H N H R N \CH' -> TH QH 60 CH CO CH Or 60 CHCHR ' d v C H CH-CO\/ \/\CH, O-CH,(V.1 (X.) Wa.1As is pointed out by Leuchs, a substance of formula (X) onoxidation with permanganate should yield 5-oxalylaminohexa-hydroindoline-4 : 6 : 7-tricarboxylic acid, which would give oxalicacid on hydrolysis.( X a ) on the other hand should give a @-ketonicacid, namely, 5-malonylamino-6- ketohexahydroindoline-4 : 7 -dicarb-oxylic acid, which should lose carbon dioxide and malonic acid onhydrolysis. On the basis of the Blount-Robinson formula, (X)and ( X a ) should be replaced by (XI) and (XIa).CH/ \2VH (7H\ CO,H*Cf€ ,CH60 CH YH (XIa.)CO CHWhen strychnine is reduced electrolytically to tetrahydro-strychnine, the amide group >N*CO- becomes >NH,CH,*OH-and it was shown4 that on oxidation of this with chromic acid anamino-acid, C21H2204N2, was formed in 14% yield.When hexa-hydrostrychnine was similarly oxidi~ed,~ an amino-acid, C21H2204N2;resulted which was also obtained by catalytic reduction of Leuchsacid. On this view Leuchs' acid should be C,,H,04N2. Thechanges involved, however, appeared to be complex, since theacid C21H,,0,N, of Briggs and Robinson formed a benzylidenederivative, and therefore presumably contained the reconstituted>N*CO*CH,- group of strychnine, but did not give the usualH. Leuchs and W. Wegener, Bw., 1930, 63, 2220; A., 1930, 1455; H.Leuchs, ibid., p. 3187; A,, 1931, 242.5 L. H. Briggs and R. Robinson, J., 1931, 3160; A., 178204 ORGANIC CHEMISTRY .-PART 111.strychnine colour reactions. It has now been demonstrated thatthese acids, almost certainly, contain an extra carbon atom, presentas a carboxyl group in the p-position to the indole N-atom andthat it is derived from a double molecule analogous to the redamorphous dyes obtained by H.Wieland and collaborators fromstrychnine and characterised as meriquinonoid diphenyl derivatives.This gives a satisfactory explanation of the origin of the new carb-oxyl group and of the failure t o give the normal colour reactions,since these are dependent on a free p-position.The new formulae for brucine and strychnine also give a satis-factory explanation of the neo-bases. When strychnidine metho-salts (amide group reduced to -NH*CH,-) are digested with methyl-alcoholic potassium hydroxide, they yield a methoxymethyl-dihydrostrychnidine which can be interpreted by the schemeSC*#Me S0,Me + 3C*OMe, YMe.When the quaternary salt is reconstituted by boiling dilute acid,an isomeric methylneostrychnidinium salt is formed which onheating loses methyl chloride, for instance, and gives neostrychnid-ine. Both strychnidine and neostrychnidine give the same dihydro-strychnidine on catalytic reduction, so the difference in the basesmust reside in the position of the double bond.s Strychnidine(XII) and neostrychnidine (XIII) are therefore assigned the struc-tures shown, the double bond occupying adjacent positions.TheI 1oxidation of neostrychnidine to the diketone strychnidone by per-manganate,g on this view of the constitution, would consist in thedisruption of the double bond by addition of two oxygen atomswith formation of a 10-membered ring.Subsidiary Stryc7mos Alkaloids.-The study of the constitution' H.Leuchs and H. Beyer, Ber., 1932, 65, 201; A., 407.* 0. Achmatowicz, (the late) W. H. Perkin (jun.), and R. Robinson, J . ,' G. R. Clemo, (the late) W. H. Perkin (jun.), and R. Robinson, J., 1927,Annakn, 1931, 491, 107; A., 179.1932, 486; A., 406.1589; A., 1927, 888KIN#. 205of the subsidiary alkaloids which accompany the chief alkaloid ina plant is of considerable importance, for it throws light on thegeneral scheme of phytochemical synthesis adopted by nature ina given species. Within the last few years four new alkaloids havebeen isolated from the residues accumulated by manufacturers inthe isolation of strychnine and brucine.Whether these newalkaloids are specific to Xtrycltnos Nux-vomica or Str. Ignatii orboth is unrecorded.In 1931 K. Warnat lo described the isolation of three newstrychnos alkaloids which he named a- and p-colubrines and+-strychnine. The first two dif€er in composition from strychnineby a methoxy-group and on oxidation by Spath and Bretschneider’smethod give two isomeric monomethoxyoxalylanthranilic acids.These were characterised as their dimethyl esters, that from a-colu-brine being identical with synthetic dimethyl N-oxalyl-4-methoxy-anthranilate and that from p-colubrine being identical with theisomeric 5-methoxy-derivative. This suggests that strychnine,brucine, and the two colubrines stand in the following relationship :There is no proof of the identity of the remainder of the moleculeswith that contained in strychnine or brucine, but the similarity ofproperties of all four bases suggests identity.The third alkaloid, $-strychnine, has been examined by B.K.Blount and R. Robinson 11 and the original preliminary observationsof Warnat confirmed. Its composition is that of a hydroxy-strychnine and on reduction in acid solution it yields strychnine.It is relatively stable to ferricyanide, forms an N-nitroso-derivative,and on crystallisation from methyl or ethyl alcohol yields methylor ethyl derivatives which are readily hydrolysed in cold acidsolution with formation of +strychnine. These properties andothers suggest that +-strychnine carries a tertiary alcohol group ona carbon atom adjacent to the basic N-atom in strychnine.Onthis view the nitrosoamine would be >CO,NO*N< and the ethers>C(OR)-N<.The fourth subsidiary alkaloid isolated from manufacturers’residual liquors is vomicine, l2 C,,H,,O,N,, differing from strychnine(C,,H,,O,N,) by CH202. It contains an aromatic ring, since it iseasily brominated, and has one nitrogen in combination as a lactam,10 Helv. Ghim. Actu, 1931,14, 997; A., 1931, 1312.11 J., 1932, 2305; A., 1147.12 €1. Wieland and G. Oertel, Annulen, 1929, 469, 193; A., 1929, 708206 ORGANIC CHEMISTRY .-PART 111.since boiling alcoholic potassium hydroxide gives vomicinic acid,C,2H2G03NZ, a substance which is very readily autoxidisable and isconverted into the original base by the action of acids.On catalyticreduction vomicine adds on two hydrogen atoms, indicating thepresence of a double bond. It readily forms a benzoyl derivativeand on reduction with hydriodic acid gives deoxyvomicine,C,2H,,0,N,, these properties suggesting the presence of a tertiaryalcoholic group. Unlike strychnine, vomicine does not add onmethyl iodide at the basic N-atom, but vomicinic acid on methyl-ation yields N-methylvomicinic acid and its methyl ester, togetherwith two parallel products each containing a CH, group more,vix., an acid C,,H,,O,N, and an ester C,,H,,0,N,.13 The acidC,,H,,O,N, can be converted by alcoholic potassium hydroxidewith difficulty into N-methylvomicinic acid. This suggests thepresence of a phenolic group, which would also account for theready autoxidation of vomicinic acid.This finds expression inthe partial formula (I) for vomicine and (11) for vomicinic acid.Vomicine, like brucine, is seiisitive to chromic acid and givesan important series of degradation product8s.14 The chief acidformed has the composition C,,H,,O,N, and very readily losescarbon dioxide. The carboxyl group is therefore probably adjacentt o a hydroxyl group. By analogy with the results obtained by theaction of chromic acid on brucine and strychnine the degradationof vomicine may be represented thus :OH OHI CH,-The base C,,H,,O,N, obtained on decarboxylation of this acidIt can also contains a hydroxyl group which can be benzoylated.13 H.Wieland and F. Calvet, AnnaZen, 1931, 491, 117; A., 179.1 4 H. Wieland and G. Oertel, ibid., 1929, 469, 193; A., 1929, 708; H.Wieland, F. Holscher, and F. Cortese, ibid., 1931, 491, 133; A., 179KING. 207be reduced catalytically to C16H2602N2, probably through reductionof a double bond and of the ether linkage :sC-O-C< + 5CH CHE + H20.The two extra oxygen atoms in vomicine which are not foundin strychnine are thus accounted for as a tertiary alcohol groupand a potential phenolic group. If the remainder of the ringsystems of strychnine and vomicine is the same, and there is no evi-dence so far inconsistent with this view, the only additional differencewill be in the possession by vomicine of an extra methyl group.Yohimbine.-A group of alkaloids of which yohimbine is thechief representative has been obtained from Corynanthe Johimbe,of the natural order Rubiacece to which the cinchona plants belong.Six alkaloids, yohimbine, yohimbene,15 aZZoyohimbine,16 iso-yohimbine,16 a-l' and yl8-yohimbines, have been definitely identifiedand they all appear to have the formula C2,H2,0,N2.In addition,a seventh isomeric alkaloid, corynanthine, has been obtainedby E. Fourneau and Piore l9 from Pseudocinchom africuna, of thesame natural order as the above. All these alkaloids are mono-methyl esters which on hydrolysis yield monocarboxylic acids,and four of them, yohimbine, yohimbene, y-yohimbine, and iso-yohimbine, give isomeric acids which on decarboxylation yieldone and the same alcohol, yohimbol.20 aZZoYohimbine gives anisomeric alcohol, alloyohimbol.Corynanthine and a-yohimbinegive neither yohimbol nor alloyohimbol. The four alkaloids whichgive yohimbol, when treated with selenium and soda-lime in a vacuumsublimation apparatus, give one and the same substance, to whichthe formula ClgH12N,*O~C,gHlzN2 is assigned by G. Hahn and W.Schuch,2O but which according to F. Mendlik and J. P. Wibaut 21is a base, C,,H1,N,, t o which the name yobyrine is given. Thedifference between the four alkaloids named must accordingly bedue t o a different situation for the carbomethoxy-group in themolecule.A number of degradation products have been obtained fromyohimbine, some of which have been identified. G. Barger andl5 G. Hahn and W. Brandenberg, Ber., 1926, 59, 2189; 1927, 60, 707;A., 1926, 1263; 1927, 471.l6 Idem, Ber., 1927, 60, 669; A., 1927, 471; K.Warnat, ibid., 1926, 59,2388; 1927, 60, 1118; A., 1926, 1263; 1927, 681.17 R. Lillig and H. Kreitmair, Merck's Jahresber., 1928, 42, 20; B., 1930,485; G. Hahn, and W. Schuch, Ber., 1930, 63, 1638; A., 1930, 1194.1s G. Hahn and W. Schuch, Eoc. cit.19 Bull. SOC. chim., 1911, [iv], 9, 1037; A , 1912, i, 49.20 Ber., 1930,63, 1638, 2961; A., 1930, 1194; 1931, 243.21 Rec. trav. chim., 1931, 50, 91; A,, 1931, 369208 ORGANIC CHEMISTRY .-PART III.(Miss) E. Field 22 showed that yohimboaic acid when distilled withlime gives a dimethylindole with an odour of scatole, and whichgives a, crystalline picrate. The same dimethylindole, m.p. 55", wasobtained by E. Winterstein and M. Walterz3 by distillation of theacid and by K. Warnat24 by heating the acid with soda-lime orzinc dust. This indole is not identical with any known dimethyl-indole, and synthetic experiments by F. Mendlik and J. P. Wibaut 25show that it is not identical with 3 : 5-, 3 : 6-, or 3 : 7-dimethyl-indole. The colour reaction of yohimbine with sulphuric acid andpotassium dichromate is similar to that given by strychnine andsuggests a relationship. In fact E. Spath and 1%. Bretschneider 26find that both alkaloids on oxidation with alkaline permanganategive N-oxalylanthranilic acid (I). In the case of strychnine thisacid is known to arise from an indole nucleus, but in the case ofyohimbine a quinoline structure is not excluded.(1.1 (11.) (111.)When yohimbine is boiled with acetic anhydride and sodiumacetate, it gives a crystalline ON-diacetylyohimbine and an amor-phous monoacetyl derivative.27 The former on oxidation withdilute nitric acid gives succinic acid and a 6-nitroindazole-3-car-boxylic acid (11), the constitution of which follows from its de-carboxylation to 6-nitroindazole identical with the synthetic pro-duct.28 The indazole structure is probably not present in the originalmolecule, but arises by the action of nitrous acid on an o-amino-phenylacetic acid group as is shown in (111).The formation of theindazole is exactly analogous to the formation of 4-nitro-5-(3-pyridyl)-pyrazole from nicotine by the action of nitric acid.29Two other degradation products of yohimbine which have beendefinitely identified are o-oxycarbanil, Ph<-o>CO, which is NH22 J ., 1915, 107, 1025.23 Helv. Chim. Acta, 1927, 10, 5 7 7 ; A., 1927, 1205.24 Ber., 1927, 60, 1118; A., 1927, GSl.25 Rec. Irav. chim., 1931, 50, 91; A., 1931, 369.2o Ber., 1930, 63, 2997; A., 1931, 242.27 A. Schomer, Arch. PharnL., 1927, 265, 500; A., 1927, 1097.28 G. Hahn and F. Just, Ber., 1932, 65, 717; A., 760.G. A. C. Gough and H. King, J., 1931, 2968; A . , 68; Ann, Reports,Compare also I<. Warnat, Ber.,1926, 59, 2388; A., 1926, 1263.1931, 28, 166KING. 209obtained by the action of permanganate on yohimboaic acid indilute alkali at room temperature,30 and isoquinoline, obtained insmall yield by distillation of yohimboaic acid with zincWhen yohimboaic acid is distilled or fused with potassiumhydroxide or heated with zinc dust 23 or with lime,22 it yields abase, C13Hp$2, which, like the parent alkaloid, must contain atertiary N-atom, since it forms a methiodide and according toWinterstein and Walter is accompanied by a second base, C12Hl&..The disposition of the ring systems in these bases is unknown,but it is probably the same as occurs in the products of the actionof selenium on yohimbine.When this alkaloid is heated withselenium,25 it yields three substances : yobyrine, C,,H,,N, ;dihydroyobyrine, C1,H2,N2 ; and ketoyobyrine, C ~ O H ~ ~ O N ~ .Yobyrine differs from yohimbine by a carbomethoxy-group, amolecule of water and four hydrogen atoms, and ketoyobyrine mustbe formed by condensation of the carbomethoxy-group with elimin-ation of methyl alcohol and formation of a bridge.On fusion withpotassium hydroxide ketoyobyrine yields a basic substance,C,,H,,O,N,, and an acid identified as 2 : 3-dimethylbenzoic acid.It has been suggested25 that this is the benzene nucleus whichappears as dimethylindole by other methods of degradation, inwhich case o-oxycarbanil, oxalylanthranilic acid, and indazole-carboxylic acid must arise from a second benzene nucleus with anitrogen atom adjacent to it. Furthermore the base C13H12N2(IV), differing from yobyrine, C1,H,,N2 (V), by C,H6, is consideredby the same authors t o have lost four carbon atoms of the benzenenucleus with the two o-methyl groups attached, as is shown below :MeThis benzene nucleus is supposed t o be present in yohimbine as ahydroaromatic structure which is dehydrogenated by selenium butdegraded by other reagents.Pyrrole Pigments .31The remarkable progress which has been made in the last 30years in the elucidation of the structure of blood and leaf pigmentsis mainly due t o the efforts of Nencki, Kuster, Piloty, Willstiitter,and Hans Fischer and their pupils.The brilliant researches of the30 K. Warnat, Rer., 1926, 59, 2388; A., 1926, 1263.31 Valuable summaries by H. Fischer can be found in ibid., 1927, 60, 2611 ;Naturwias., 1930, 18, 1026; Nobel Vortrag, Dec. Ilth, 1930210 ORUANIC CHEMISTRY.-PART III.last-named were fittingly recognised by the award of the Nobelprize in 1931.The following account has been written to enable the reader t oappreciate the position which has been reached in the chemistryof the blood and bile pigments and also as an introduction to thechlorophyll problem.Hamin, obtained from blood by heating with acetic acid andsodium chloride (Teichmanii's test), has the constitution (I), as isshown by its properties and by synthesis.It consists of fourpyrrole-like nuclei joined in the cc-position by methine groups and apeculiar conjugated system of double bonds responsible for thecolour. The iron is held in complex combination, since it does notshow the ordinary ionic reactions of iron. Inspection of the formulashows how it can give rise to four different hzmopyrrole bases (11-V) by drastic reductive fission with hydriodic acid and also t o thefour corresponding hzmopyrrolecarboxylic acids (3'1-IX).Me-EtMe1] IIH \/(11.) NH\/(VI.) NHHaemopyrrolc.Me-XMe" IIHHzmopyrrole-carboxylic acid.Me - EtHI1 (/Me \/(111.1 NHMe-XCryp topyrrolc.HI1 IIMe v (VII.) NHCryptopyrrole-carboxylic acid.Me--Et Me-EtMe1' IlMe HI1 IIH\/ (v.) NH\/(IV.) NHPhyllopyrrole.Opsopyrrole.Me-X Me - XMe1/ '/Me HI1 I/H\/(IX.) NH\/(VIII.) NHPhyllop yrrole - Opsop yrrole-carboxylic acid. carboxylic acid.On oxidation, the nuclei bearing vinyl groups are completelydegraded but the acidic nuclei appear as hzmatic acid (X). If thevinyl groups are converted into ethyl groups by reduction of hzminwith hydriodic acid or catalytically to mesoporphyrin, the hematicacid obtained by oxidation is accompanied by methylethylmalein-imide (XI).(x.) Me---X o\)oThese reductive and oxidative processes can nowadays be sKING.21 1oontrolled that they give a clue t o the number of nuclei of agiven type within the molecule of a pigment. When the iron isremoved from haemin by various reagents, a series of porphyrinsis obtained characterised by their fluorescence, dichroism, and thepossession of absorption spectra in the visible and the ultra-violetregion.32The more important porphyrins derived from haemin are shown inthe following table. In column 3 is shown the number of isomeridesobtainable by altering the sequence of groups around the pyrrolerings in the P-position with the condition that each pyrrole nucleusmust bear one methyl group, whilst in column 4 is recorded thenumber of isomerides synthesised to date by H.Fischer and hiscollaborators.Isomerides. Side Chains.Possible. Synthesised. ~ A \Haemin C3,H3,0,N4FeCl 15 P3 4Me 2X 2CH:CH,Protoporphyrin C3,H3,04N4 15 233 4Me 2X 2CH:CH,Haematoporphyrin C3,H3 ,O ,N4 15 233 4Me 2X 2CH(OH)MeMesoporphyrin C34H3 @,N, 15 1234 4Me 2X 2EtXtioporphyrin C32H3 ,N4 4 4s5 4Me- 4EtDeuteroporphyrin C3,H3,04N, 15 336 4Me2X -Deuterohaemin C30H,,0,N4FeC1 15 233 4Me2X -A number of porphyrins have been found to occur naturally inyeast, pearl-oysters, mussels, feathers, egg-shells, and in cases ofhzematoporphyrinuria, and representatives of some of these havebeen synthesised.Coproporphyrin C3,H380 ,N4 4 437 4Me - 4 XConchoporphyrin C3,H3,0 4Me 3X 1 succinic acidOoporphyrin C34H3404N4 15 233 4Me 2Et BCH:CH,Uroporphyrin CIoH3 ,O ,N, 4Me - methylmalonic &Isornerides.Side chains.Possible. Synthesised. ~ - \succinic acid~~~32 A. Treibs, Z. physioE. Chem., 1932, 212, 33; W. Hausmann and 0.Krumpel, Biochem. Z., 1927, 186, 203; A., 1927, 893.33 H. Fischer and A. Kirstahler, Annalen, 1928, 466, 178; A., 1928, 1385;H . Fischer and L. Niissler, ibid., 1931, 491, 162; A., 173.34 H. Fischer and co-workers, ibid., 1927, 452, 289; A., 1927, 469; ibid.,459, 74; A., 1928, 76; ibid., 1928, 468, 166; A., 1928, 1384; ibid., 1929,475, 274; A., 1929, 1466; ibid., 1930, 480, 260; A., 1930, 932; ibid., 482,211; A., 1931, 101; ibid., 484, 85; A., 1931, 240.35 Idem, ibid., 1926, 448, 186, 201; A., 1927, 962, 963; ibid., 450, 190;A., 1926, 1261; ibid., 1927, 452, 285; A., 1927, 469; ibid., 459, 71; A.,1928, 76; ibid., 1928, 466, 211; A., 1928, 1382; ibid., 1932, 495, 26; A., 756.36 Idem, ibid., 1928, 466, 183; A., 1928, 1385; ibid., 1929, 473, 245; A.,1929, 1184; ibid., 1931, 491, 173; A., 173.37 Idem, ibid., 1926, 450, 214; A., 1926, 1261; ibid., 1927, 457, 97; A.,1927, 1088; ibid., 458, 132; A., 1927, 1206; ibid., 1928, 461, 276; A., 1928,776; ibid., 462, 249; A., 1928, 902; jbid., 466, 156; A., 1928, 1384; 2.physiol. Chem., 1929, 182, 265; A., 1929, 940; ibid., 1931, 196, 163, 236;A., 1931, 747, 853212 ORGANIC CHEMISTRY .-PART 111.Incidentally a large number of importanthave been prepared.Isomerides.Possible.Synthesised.Porphinmonopropionic acid 8 838Porphintripropionic acid 8 139Tetramethyltetrapropylporphyrin 4 440P yrroporphyrin 24 841PyrroEtioporphyrin 8 8 4 2Deuteroaetioporphyrin 15 9 4 3Rhodoporphyrin 24 .)44isouroporphyrin 4 345related porphyrinsSide chains.4Me 3Et 1X4M0 1Et 3X4Me 4Pr -4Me 2Et 1X4Me 3Et -4Me 2Et -4Me 2Et 1C02H 1X4Me 4CH(C02H),Ztioporphyrin, C32H38N4, which is obtained indirectly by a,pyrogenetic reaction from hematoporphyrin, is a fully substitutedporphyrin and is a convenient reference substance for all otherporphyrins. Four atioporphyrins are possible which, followingthe recognised procedure, are shown in abbreviated form as follows,each bracket representing a pyrrole nucleus, since the remainderMe Et Me E t Me Et Me E tI I -Me Me-l--l Et Me-] I-& Et 1 I-Et.I 1 L II 1 1 111: 1 [ Iv jlMrI -Me -Et Et Me Et- -Et Me I-I I-! Et Me Et Me Me Etof the molecules are identical in most porphyrins.All the porphyrinstabulated can be referred t o one of these four structures and it isknown, for instance, that natural hEmin has its substituents basedon atioporphyrin (111) and so has chlorophyll. If the ethyl groupsare replaced by propionic acid groups (X), there will be four possiblecoproporphyrins, all of which have been synfhesised and two ofthem, coproporphyrins (I) and (111), are identical with naturallyoccurring coproporphyrins.If, however, only two of the four38 H. Fischer and co-workers, Annalen, 1928, 461, 237; A., 1930, 651;ibid., 1929, 471, 293; A., 1929, 941; ibid., 475, 254; A., 1929, 1465; ibid.,1931, 492, 27, 50; A., 173.Idem, ibid., 1930, 479, 32; A., 1930, 621.40 Idem, ibid., 1931, 486, 20; A., 1931, 746.4 1 Idem, ibid., 1929, 473, 229; A., 1929, 1184; ibid., 1930, 480, 136; A.,1930, 931; ibid., 482, 199; A., 1931, 101.42 Idem, ibid., 1928, 466, 211; A., 1928, 1382; ibid., 1929, 473, 243; A.,1929, 1184; ibid., 1930, 480, 126; A., 1930, 931; ibid., 482, 199; A., 1931,101.43 Idem, ibid., 1928, 466, 217; A., 1928, 1382; ibid., 1930, 482, 209; A.,1931, 101; 2. phy5iOZ. Chem., 1931, 198, 56; A., 1931, 967.44 Idem, Annalen, 1929, 473, 237; A., 1929, 1184; ibid., 1930, 480, 109;A., 1930, 931.45 Idem, ibid., 1927, 457, 91; A., i927, 1088; ibid., 1930, 483, 1 ; A., 1930.1599; 2.physiol. Chem., 1932, 204, 68; A., 285KING. 213ethyl groups of aetioporphyrin are replaced by propionic acidgroups as in mesoporphyrin, then fifteen mesoporphyrins arepossible, 1 and 2 derived from Ztioporphyrin (I), 3-5 fromatioporphyrin (11), 6-11 from aetioporphyrin (111), and 12-15 fromaetioporphyrin (IV), and of these twelve have been synthesised.Me X Me Et Me XI 1Me XX MeI I MeEt MeMe X Me X Me X Me Et -- n -Et Me-Me[ ' AM, E t LEt u X MeMe Et Me Et Me X Me EtMe Me Me Me 1 Me X 179 ] [ 10 ] [ 11 ] [ 12 1; Et Me 1-1Me X I x xEt Me I X Et XP M e Et MeMe X Me X Me X n X X '1 13 ] [ 14e I I Me 'At MeMe Me EtTheir dimethyl esters have characteristic melting points and areespecially valuable for characterisation, since the decarboxylationproducts, the aetioporphyrins, have no defhite or very high meltingpoints. There are as many hamins possible as there are meso-porphyrins, since the ethyl groups are replaced by vinyl groupsand introduction of iron does not so far as is known increase thenumber of possible isomerides.Natural hamin corresponds tomesoporphyrin 9, as will be seen by comparison with the formulafor hamin given a t the beginning of the section. The first proofthat hamin had this particular orientation of groups in the p-positionswas afforded by the synthesis of mesoporphyrin 9, identical withthe product obtained from natural h a m i r ~ .~ ~Space does not allow an account of the variety of syntheticmethods used by H. Fischer and his collaborators in the preparation46 H. Fischer and G. Stangler, Annalen, 1927, 450, 53; A., 1928, 76214 ORGANIC CHEMISTRY .-PART 111.of the many porphyrins so far synthesised. Reference can only bemade t o the representative synthesis of natural hemin (haemin IX)and hsmin I11 corresponding to mesoporphyrins 9 and 3 respec-tively.2 : 3-Dimethylpyrrole and 2 : 4-dimethylpyrrole-&aldehyde werecondensed by alcoholic hydrobromic acid t o 4 : 5 : 3’ : 5’-tetra-methylpyrromethene hydrobromide (A), whilst cryptopyrrole-carboxylic acid (VII, p. 210) on bromination gave 5 : 5’-dibromo-3 : 3’-di-p-carboxyethyl-4 : 4’-dimethylpyrro-2 : 2’-methene hydro-bromide (B) 47 with loss of a methylene group.When (A) and (B)were heated in succinic acid a t 180-190”, deuteroporphyrin (C;R = H) was obtained.48Me-H Me=====€€ R CH Me(A*) Melt II-cH-1 1 Me/\/ \/\R\/ NH - \ 2 I e NHBr yJyH Ni=/ --+ c H Y H N , d M e \CH (C.1NH NHBrB r A CH=/NBr Me\ \\ A//Me![ II? XI-lMe X CH XThe latter was converted into deuterohaemin by the action offerrous acetate, acetic acid, sodium chloride, and ‘hydrochloricacid, since the pyrrole nuclei in the iron complexes are more reactivethan in the iron-free porphyrins. On treatment of deuterohaeminwith acetic anhydride in presence of stannic chloride, diacetyl-deuterohzmin was obtained and it was characterised by conversioninto diacetyldeuteroporphyrin (C; R = Ac).On reduction ofthis porphyrin with alcoholic potassium hydroxide the &-secondaryalcohol, hzmatoporphyrin [C ; R = CH(OH)Me], was obtainedin 24% yield, calculated on the deuterohzmin used. This por-phyrin proved to be identical with the natural product obtainedfrom haemin. It was quantitatively converted by heating ina high vacuum at 105” into protoporphyrin (C; R = CHZCH,),which with ferrous iron gave hemin (p. 210) identical with thatobtained from haemoglobin.It is a remarkable fact that the structure of hzmin as now deter-mined by synthesis was suggested as early as 1912 by W. ICii~ter,~~with the same orientation of groups in the P-positions except that amethyl and a vinyl group on one nucleus had to be interchanged.Moreover, it was not until hemin was synthesised that its constitu-tion was known with certainty, since immediately preceding its47 H.Fischer and H. Andersag, Annalen, 1927, 458, 135; A., 1927, 1206.48 H. Fischer and A. Kirstahler, ibid., 1928, 466, 178; A., 1928, 1385.49 2. physiol. Chem., 1913, 82,463; A., 1913, i, 210m a . 216synthesis it was still believed to contain one acetylene and one vinylgroup.50More recently H. Fischer and L. Niissler 51 have synthesisedhaemin I11 with an orientation of groups identical with that suggestedby Kuster for natural hzemin. The corresponding deuteropor-phyrin I11 (D) was obtained by condensation of 5 : 5’-dibromo-4 : 4’-dimethyl-3 : 3’-di-p-carboxyethylpyrro-2 : 2’-methene hydro-bromide (E) and 4 : 5 : 4’ : 5’-tetramethylpyrro-2 : 2’-methene hydro-The subsequent steps were then on the same lines as for thesynthesis of natural hamin IX.All authors are agreed that in haemin the iron is in the tervalentstate and on its reduction to the bivalent state a haemochromogenis obtained accompanied by a change in the spectrum and a decreasein stability.Hitherto haemochromogen was always stabilised byformation of complexes with nitrogenous bases such as nicotine,pyridine, and hydrazine, but it has now proved possible to isolate thehsms or complex salts with bivalent iron but without nitrogenousaddenda.52 Thus, if suitable porphyrins are treated in nitrogenwith a ferrous salt, crystalline haems are obtained. This has beenfound possible for proto-, aetio- and meso-porphyrins and theiresters and the products on addition of pyridine give intense hzemo-chromogen spectra. Hzemoglobin is a molecular compound ofhsm and globin, but it is exceptional in that it has no hzemo-chromogen spectrum. I n this connexion it is of interest thathamatin (hzem-oxide) can form additive products with glyoxaline,methylglyoxaline, and pilocarpine.53 The additive product withtwo molecular proportions of glyoxaline separates unchanged frompyridine solution and does not part with its glyoxaline even a t 100”.Glyoxaline has thus the greatest affinity for hzematin and sincehsmatin and globin combine t o give methzemoglobin,M the sugges-H. Fischer and G. Stangler, Annalen, 1927, 459, 53 ; A., 1928, 76.51 Ibid., 1931, 491, 162; A . , 173.52 H. Fischer, A. Treibs, and K. Zeile, 2. physiol. Chem., 1931, 195, 1;53 W. Langenbeck, Ber., 1932, 65, 842; A , , 757.A., 1931, 633.R. Hill and H. F. Holden, Biochem. J., 1926, 20, 1326; A., 1927, 67216 ORGANIC CHEMISTRY .-PART 111.tion is made 53 that the combination is through the glyoxalinenuclei of histidine, the characteristic amino-acid of globin.Bile Pigments.-Bilirubin, C,,H,,O,N,, is a bile pigment which issupposed to arise from the break-down of haemoglobin in cells ofthe reticulo-endothelial system, especially those of the liver. Itis a rare substance difficult to obtain, the best source being oxgall-stones. It differs from hzmin by having one carbon less, twooxygen atoms more, and no iron. It has no characteristic absorptionspectrum, so the porphyrin ring-system is probably absent. It ischaracterised by striking colour reactions, of which Gmelin’s is themost important. This may be carried out by carefully adding nitricacid containing nitrite to a solution of the pigment in chloroform.The latter passes through the colour changes green, blue, violet,red, and finally yellow.55 On energetic oxidation with chromicacid bilirubin gives haematic acid56 (X, p. 210) and on energeticreduction with hydriodic acid, cry-ptopyrrole (111, p. 210) andcryptopyrrolecarboxylic acid 57 (VII, p. 210).The most important derivatives are those obtained by gentlereduction. Sodium amalgam or catalytic reduction yields meso-bilirubin, C3,H,,06N4 ; this on further reduction yields meso-bilirubinogen (urobilinogen), which gives an intense colour reactionwith Ehrlich’s p-dimethylaminobenzaldehyde reagent. Meso-bilirubin on oxidation gives haematic acid (X, p. 210) and methyl-ethylmaleinimide (XI, p. 210) just as mesoporphyrin does. Onreduction with hydriodic acid and acetic acid mesobilirubin yieldsa mixture of two acids which differ from each other in compositionby a methylene group : bilirubic acid, C1,H2,03N2, and neobilirubicacid, Cl,H2,0,N,, both of which on further reduction give rise tocryptopyrrole (111, p. 210). The acidic reduction products are, how-ever, different, for bilirubic acid gives cryptopyrrolecarboxylicacid (VII, p. 210) whilst neobilirubic acid gives haemopyrrolecarboxylicacid (VI, p. 210). These observations receive a ready explanationon the formulm (I) for mesobilirubin, (11) for bilirubic acid, and (111)for neobilirubic acid.55Me-Et Me-X X-Me Et-Me CH= I-IoH (I). HO~-I=CH--II ll-c~~-Il I(_ v \.YN v NH NH\/NMe-Et Me-X X-Me Et-MeHI1 II-CH -11 llOH \/ \/HOll Il-cH2-II IlMeNH (111.1 NH\/ \/NH (11.) NH55 H. Fischer and R. Hess, 2. phpiol. Chern., 1931,194, 201 ; A., 1931, 497.56 W. Kiister, ibid., 1898, 26, 314; A., 1899, 314.5 7 H. Fischer and E. Adler, ibid., 1931, 197, 237; A., 1931, 967KINU. 217These two acids (11) and (111) are the leuco-compounds corres-ponding to xanthobilirubic acid (IV) and neoxanthobilirubicacid (V), into which they are respectively converted by the actionof sodium methoxide 58 or potassium meth0xide.5~Conversely, neoxanthobilirubic acid (V) is converted by condens-ation with formaldehyde into mesobilirubin (I), which gives theGmelin reaction and is identical with the product obtained frombilirubin. This incidentally supports the symmetrical structureassigned to mesobilirubin, and mesobilirubinogen will be the corres-ponding trimethane derivative. The orientation of the groupsattached to the pyrrole nuclei follows from the synthesis of xantho-bilirubic and neoxant hobilirubic acids. 5-Aldehydo-3-methyl-4-e t hylpyrrole-2 - carboxylic acid (VI) and crypt op yrrolecarboxylicacid (VII) condense in presence of a large excess of hydrobromicacid to give 5-carboxy-4 : 3’ : 5’-trimethyl-3-ethylpyrromethene-4‘-propionic acid hydrobromide (VIII), which on bromination gives5- bromo -4 : 3’ : 5’ - trimet hyl-3-et hylpyrromet hene-4’-propionic acidhydrobromide 59 (IX). The latter on treatment with potassium orsilver acetate yields xanthobilirubic acid (X) identical with theproduct from natural sources.Me-Et Me-X Me-Et Me-XC02HII IIcHo HI/ - C02Hl-I=CH--/J v NH\/NHBr v NH v NH(VI.1 (VII.) (VIII.) 1 Me-Et Me-X Me-Et Me-X I1 llMe t- BJ---I=CH--II l l ~ , v \/ v NHBr (IX.) NHThree isomerides of xanthobilirubic acid are possible and all weresynthesised by suitable methods. When xanthobilirubic acid wasbrominated, it gave an unstable substance which on treatment withpyridine passed into mesobilirubin identical with that from naturalbilirubin.60 During this synthesis one carbon atom is lost (theethanes are unstable), for which there are many analogies in theH O ~ ) = CH-N (x.) NH58 H. Fischer and H. Rose, Ber., 1913, 46, 439; A., 1913, i, 382.59 H. Fischer and H. Berg, Annalen, 1930. 482. 189; A., 1931, 101.6o H. Fischer and E. Adler, 2. physioE. Chem., 1931, 200, 209; A., 1931,1420218 ORQANIC CHEMISTRY .--PART 111.syntheses of dipyrromethanes from methylbrominated pyrroles.61Since mesobilirubin on reduction with hydriodic acid gives neobilirubic acid or by fusion with resorcinol gives neoxanthobilirubicacid, the synthesis of xanthobilirubic acid is also a synthesis ofneoxanthobilirubic acid. In a similar manner bromination of theisomeric mesobilirubic acids gave isomeric mesobilirubins, all ofwhich are important, since there is some evidence that more thanone bilirubin occurs in nature.On the basis of the results recorded above, the most probableformula for bilirubin is (XI).Me---CH:CH, Me-X X-Me CH,:CH,===,Me HoI-cH-~I 11-\//OHCH,-lI 11- CH=N v v NH (XI.) NHSuch a structure has an orientation of groups in the P-positionscorresponding to a mesoporphyrin 13 (p. 213) or an aetioporphyrinIV (p. 212), which has no other natural representative. It followsfrom this that the conversion of haemoglobin into bilirubin mustinvolve intermediate degradation to pyrrole units. Against theabove structure for bilirubin is the observation that on oxidationwith nitrous acid a substance is formed which has a composition,C7H7O2NY agreeing with that of methylvinylmaleinimide, but oncatalytic reduction takes up two hydrogen atoms to give a substancewhich is not methylethylmaleinimide. Formulae have been suggestedfor these substances containing fused pyrrofuran rings producedby ring-formation between the vinyl group and an a-hydroxyl group,but this is difficult to reconcile with the relative orientation of thevinyl and hydroxyl groups necessitated by (XI). The final decisionwill no doubt depend on a synthesis of the structure (XI).The nomenclature of the porphyrin group is applicable to thebilirubin group. If the vinyl groups in (XI) are replaced by prop-ionic acid (X) groups, a coprobilirubin which may occur naturallyin certain pathological conditions is produced corresponding toaetioporphyrin IV and such a coprobilirubin (XII) has beensynthesised. 62Me-X Me-X X-Me X---Me\/--NHO(\~=CH-~(J~-CH,-,,- II I1 CH=I-lOH ,,/N NH (XII.) NH NIf the vinyl and propionic acid groups are replaced by ethylgroups, an aetiomesobiliru bin or decarboxylated mesobilirubin isproduced, of which one example has also been ~ynthesised.~~61 H. Fischer and P. Halbig, Annalen, 1926, 447, 123; A., 1926, 621.E2 H. Fischer and E. Adler, 2. physiol. Chem., 1932, 210, 139; A., 1045.63 H. Fischer and E. Adler, ibid., 1932, 206, 187; A., 627KmQ. 219When mesobilirubin (I) is oxidised with ferric chloride, a ferri-chloride of a new pigment, ferrobilin, is obtained,64 which by theaction of alkali gives glaucobilin (XIII). The particular orientationof pyrrole linkages ascribed to it follows from its synthesis by theaction of formic acid on neoxanthobilirubic acid (V).The vinyl analogue of this substance in which the ethyl groupsare replaced by vinyl groups has now been found in nature,65 but atrue pyrrole structure is preferred for a terminal nucleus ratherthan for one of the central nuclei as shown in (XIII). This sub-stance occurs as uteroverdin in the dog’s placenta, as a constituentof the pigments of birds eggs (sea-gulls eggs gave 250 mg. from5 kg. of shells), and as a by-product in the extraction of bilirubinfrom ox gall-stones. It has also been obtained artificially byoxidation of bilirubin with ferric chloride and is hence called de-hydrobilirubin. The constitution assigned is supported by the re-sults of reductive fission-formation of bilirubic acid-and oxid-ation-formation of methylethylmaleinimide after preliminaryreduction but not before.HAROLD KING.c4 H. Fischer, H. Baumgartner, and R. Hess, 2. physiol. Chem., 1932, 206,201 ; A., 627.65 R. Lemberg, Annalen, 1931, 488, 74; A., 1931, 1066; R. Lemberg andJ. Barcroft, Proc. Roy. Soc., 1932, [B], 110, 362; A., 627; R. Lemberg,Annalen, 1932, 499, 25

ISSN:0365-6217    

DOI:10.1039/AR9322900096

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

ANALYTICAL CHEMISTRYIN the period under review there is little new material of outstandingimportance. The most interesting work in analytical chemistryhas dealt with the detailed investigation of known processes andwith the perfection of details and apparatus in such modern processesas electrometric determinations. The following discussion will bedevoted mainly to considering some of the more important subjectsinvestigated .Quantitative Separation of Hydroxides.-The separation of metalsby precipitation as hydroxide is usually incomplete owing t o co-precipitation or adsorption of other metal radicals, to the colloidalcharacter of the precipitates in their initial stages, to the fact thatthe hydroxides can only be precipitated when a particular pH isattained, depending upon the metal, and also in part owing to theprecipitation of more or less basic salt which is hydrolysed veryslowly.The range of pH for precipitation of the hydroxides isconsiderable, in some cases being below 4. A full discussion ofthe mechanism of hydroxide precipitation has been given byH. T. S. Britt0n.lIt is a matter of experience that the separation is more completethe denser the precipitate of hydroxide. Of the substances triedby us, hydroxylamine is found t o be helpful in decreasing thegelatinous character of some hydroxides, e.g., chromium hydroxideprecipitated by ammonia. A promising method is described byF. L. Hahn2 in which a mixture of sodium azide and sodiumnitrite in dilute solution is added t o a faintly acid solution of iron,aluminium, or chromium.This reagent is effective in separatingthis group of metals from large admixtures with the nickel group.The precipitate forms quickly and is easily separated by filtration.A double precipitation will, for example, give a complete separationof iron from manganese. This method of precipitation does notintroduce into the substances under test any foreign metallicradical, in contradistinction to the older barium carbonate process.Frequently, however, the addition of another metal is of no im-portance, and precipitation of the iron group of metals, by meansof zinc oxide, for example, has the advantage of rapidity. Theuse of zinc oxide is not new, but the conditions for completenessof separation, particularly as applied to the analysis of alloy steels,“ Hydrogen Ions,” Chap.15. Ber., 1932, 65, [B], 64; A., 244ELLIS AND FOX. 221have now been carefully in~estigated.~ Britton has shown that zinchydroxide begins to precipitate at pH 5.2, iron and aluminium atlower pH, cobalt, manganese, and bivalent metals generally athigher pH. On this basis a separation might be expected, and it isfound that the zinc oxide method can be successfully applied tothe separation of iron, tungsten, vanadium, chromium, uranium,aluminium, and titanium from cobalt, manganese, and nickel inthe analysis of steel. Although the separation of cobalt andmanganese is easily effected and is complete, nickel cannot be soreadily separated despite the fact that the pE for initial precipitationof these metals is nearly the same.On the other hand, tervalentchromium is completely precipitated by zinc oxide, although theinitial pH for precipitation is very close t o that of zinc. While theforegoing method for determination of cobalt in materials containingiron is accurate, it is nowadays common to require determinationsof cobalt in much larger proportions than formerly in high-speedor magnet steel containing vanadium, tungsten, and chromium,amongst other metals of the alloy. The elimination of iron insuch cases by the older methods is lengthy and tedious, but may beeffected more readily by a modification of the process of extractionof ferric chloride from its solution in hydrochloric acid by meansof ether, followed by the removal of chromium, tungsten, andvanadium by t’reatment with sodium peroxide and sodium hydroxide.Traces of copper and iron may be separated by “cupferron,”leaving a cobalt solution ready for precipitation with a-nitroso-P-naphth~l.~ The process here out’lined briefly is more rapid andcertain than methods hithert,o described in which the cupferronwas not utilised to eliminate the last of the iron, and it is renderedpossible because this reagent does not interfere with the subsequentprecipitation of cobalt by the naphthol derivative.Determination of Boron.-The increasing importance of a know-ledge of the minute quantities of boron in water and natural productsis doubtless the reason for a number of papers dealing with themethod of detecting and estimating this element.There is nogreat difficulty in determining boron even in very small quantitieswhen a solution is obtained in a condition suitable for the estimation,but it is just this preliminary preparation which is not easy to carryout, and the purpose of most of the investigations is to obtain asuitable final solution and avoid loss of boron during its preparationand subsequent treatment. Some natural waters contain 0-4 mg.of boron per litre and upwards, and it has been found possible todetermine these small quantities, either in the water directly, orJ. I. Hoffman, Bur. Stand. J . Res., 1931, 7, 883; A., 137.a I-, ibid., 1932, 8, 658; B., 728222 ANALYTICAL CHEMISTRY.after concentration to a small volume with a little added alkali.At pH 7.6 boric acid is only neutralised t o the extent of about 12%but if enough mannitol is present it may be completely neutraliseda t this pH.Since other weak acids or bases are not in generalaffected by mannitol, it becomes possible t o determine boric acidby bringing the solution to pH 7.6 with sodium hydroxide eitherpotentiometrically or by means of phenol-red as indicator. As amatter of fact, if larger amount,s of mannitol are used, the endpoint may be much lower than pH 7.6, and this procedure lowersthe amount of boric acid neutralised before mannitol is added.5The determinations of boron in plant and animal tissues are nota t all so readily made as in the foregoing process, for the destruction oforganic matter, necessarily carried out as the first stage, leads toserious loss if at any point acidity is developed during heating.If the initial preparation is carried out by maintaining analkaline condition during ashing of the material, it is possible, byimpregnating turmeric-stained flax threads, to determine withsome accuracy as little as 0.01 y of boron, but the test may be tosome extent vitiated by the presence of large quantities of saltsin the ash under examination.For this reason it is usually prefer-able t o distil the acidified ash with methyl alcohol, thus volatilisingthe boron. The subsequent treatment of the methyl borate dependson the quantity present. For large quantities, such as may befound in artificial borosilicates, we have trapped the borate insodium tungstate for gravimetric determination, or in aqueoussodium hydroxide for subsequent volumetric determination in thepresence of mannitol.The choice of acid for catalysing the reactionbetween boric acid and the alcohol needs consideration in each caseexamined. Usually sulphuric acid is used and the distillation isarranged so that the acid-alcohol mixture loses most of its water,but not all, which is usually secured by passing in the vapour of freshmethyl alcohol a t nearly the same rate as that lost by distillation.For silicates, much larger amounts of alcohol and acid are required,and the water present must be regulated in order t o prevent separ-ation of silica, which adsorbs boric acid should the silica separatein a gelatinous state.6 Phosphoric acid can likewise be employedin place of sulphuric acid, but very careful attention is then neces-sary to keep too much water from distilling away, otherwise wehave found phosphoric esters to distil over with the borate, addingconsiderably to the difficulty of the final determination of the boroneven in large amounts.When plant ashes have been suitably treated, the neat andF.J. Foote, Ind. Eng. Chern. (Anal.), 1932, 4, 39; A., 242.E. Schulek and G. Vastagh, 2. anal. Chem., 1932, 87, 165; A,, 354ELLIS AND FOX. 223promising procedure recently developed for determining the boronspectroscopically is to be borne in mind.' The ashes are acidifiedwith citric acid and the boron is distilled out with methyl alcoholcontaining 5% of phosphoric acid.The methyl alcohol-methylborate mixture is burnt in oxygen in a special form of burner underspecified conditions; the flame is observed with a direct-visionspectroscope through a glass cell containing 50 ml. of water intowhich is dropped O.01N-potassium permanganate until the mostintense green boron band in the spectrum of the flame isabsorbed. A calibration curve is drawn showing ml. of 0.01N-potassium permanganate against mg. of boron. The recorded dataindicate that the method is capable of furnishing satisfactorydeterminations.Sometimes it is necessary to determine both fluorine and boron inorganic substances, and the difficulty then arises of eliminating thecarbon and preparing a residue suitable for these determinations.This problem has been examined afresh * with some measure ofsuccess for the comparatively simple substances chosen for testingthe method.Briefly the essential part of the process is the com-bustion of the substance in a Parr bomb with a mixture of sodiumperoxide, potassium chlorate, and sucrose, first enclosing thematerial in a gelatin capsule in order t o keep it away from theoxidising mixture which would otherwise attack the organic borontrifluorides with violence. The alkali is removed by boiling theliquid washed from the bomb with ammonium chloride, and thefluorine is then precipitated by means of calcium nitrate. In thespecial method of treatment of the calcium fluoride by limitedwashing, it is indicated that a solubility correction for this salt isavoided.The boron in the filtrate from the precipitated fluorideis determined in the usual way with mannitol. The results givenfor three compounds are very close to the calculated values.Conductmetric Titrations.--In view of the fact that most chemistshave made measurements of the conductivity of solutions, it issomewhat surprising that the method is not used in practice asfrequently as it deserves. It is at least as accurate as the ordinarytitration relying upon indicators, and much more so if the apparatusis chosen properly. Further, it can be employed where potentio-metric methods fail, for example, in the titration of weak acids orbases when proper account is taken of the varying slopes of theconductivity curves before and after the equivalence or neutralis-ation point is reached.The titration of strong acids and bases7 J. S. McHargue and R. K. Calfee, Id. Eng. Chm. (Anal.), 1932,4, 385 ;A., 1221.* D. J. Pflaum and H. H. Wenzke, ibid., p. 392; A., 1269224 ANALYTICAL CHEMISTRY.when coloured impurities or the natural colour of the liquid precludesthe use of indicators, is effectively carried out conductometrically,for it is not necessary to know the absolute conductivity of theliquid, the reciprocal of the resistance being sufficient for the purpose,if plotted against volume of the titration liquid. A simple form ofapparatus has been described for use with such liquid^.^ Thedifficult titrationof a weak acid by a weak basewhich must some-times be undertaken can be made conductometrically in manycases, for the electrolyte produced as soon as titration is begun is,as a rule, sufficiently strongly ionised to give a large increasein conductivity up to the point of equivalence, after whichfurther addition of titrating liquid produces very little change inconductivity.I n this case the ‘( neutral ” point of intersection isfound by producing the curve (usually a straight line as titrationprogresses) for the initial increase of conductivity and the finalstationary curve. Cases often arise where a titration, whether aneutralisation or a precipitation process, must be conducted in thepresence of alcohol ; the neutral salts produced during a titration inaqueous alcoholic solutions do not alter the “ neutral ” point, butthe curves in the neighbourhood of equivalence gradually merge intoeach other on both sides of the equivalence point.These effectshave been further studied and corrections applied €or the titrations.lOA closely allied matter is the shifting of the end-point of thetitration of a weak acid with sodium hydroxide in alcoholic solu-tions, as the proportion of alcohol increases. This is, of course,of the greatest importance in determining free fatty acids inglycerides, where alcohol is commonly used. For accurate work,corrections must be applied t o the values obtained on titration;naphtholphthalein is a better indicator for the purpose than eitherphenol- or thymol-phthalein.Of the practical applications of conductometric titrations, animportant development is the titration of small quantities of fattyacids by means of a solution of sodium hydroxide in methyl alcohol.An alcoholic solution of the fatty acid is obtained in a specialextraction apparatus, and to the solution is added a small quantityof hydrochloric acid, whereby a conducting solution results.Ontitration with the sodium hydroxide, the conductivity curve, asmeasured by galvanometer deffexions with a “ thermo-cross ”apparatus, is found to consist of three straight lines. The firstis the diminution of conductivity due to neutralisation of the smalladded quantity of hydrochloric acid, the second is the slowly9 T. Callan and S. Horrobin, J . 800. Chern. Ind., 1928,47, 3 2 9 ~ ; B., 1929,10 W.Poethke, 2. anal. Chern., 1931, 86, 399; A., 135.154ELLIS AND FOX. 225increasing conductivity due to the neutralisation of the fatty acid,and the third arises from the greatly increased rate of rise of con-ductivity due to the excess of sodium hydroxide. The projectionof the second line on the abscissa (representing volume of sodiumhydroxide added) gives the quantity of reagent required forneutralisation of the fatty acid.11 Owing to the small dissociationof the fatty acid and the use of an aqueous-alcoholic medium, itseems very likely that errors arising from shifts of the equivalencepoints are largely eliminated in the conditions of test.An unusual application of the conductometric method is thetitration, in an atmosphere of nitrogen, of tetraisoamylammoniumiodide dissolved in diethylzinc with ethylsodium in the same solvent .12It was observed, by following the course of titration, that the con-ductivity reached a minimum when equimolecular quantities hadreacted, the suggestion being that ethyltetraisoamylammonium,N(C2H5)(C5Hll)4, had been formed.Colorimetric Measurements and " Boundary Layer " PhotoelectricCells.-In using colorimeters which depend upon comparison ofdifferent thicknesses of coloured liquids, as, for example, themodern forms of the Duboscq colorimeter, the errors arising fromdifferent intensities of the coloured solutions, peculiarities of theright and left eyes, and fatigue are often ignored.Even when thetwo solutions to be compared are interchanged, divergencies ex-ceeding 1 mm.in height may be obtained. I n any general con-siderations of the best method of using colorimeters, certain factorsmust be recognised, especially, on the one hand, that the observer'seyes must be " trained," and on the other, that they become fatiguedvery rapidly. Even in an observation lasting less than ten secondsthe eye passes through the three stages, of increasing, maximum, anddiminishing delicacy of power of matching two coloured solutions.Before repeating the observation, at least five seconds are necessaryfor the eye to recover its initial power. With the object of diminish-ing errors due t o this rapid fatigue of the eye, a detailed investig-ation of the best conditions has been made and rules for the greatestaccuracy are laid down.13 The ordinary method of keeping the eyea t the eyepiece while adjusting the height of the standard colouredliquid is given up, since it involves a time of observation which bringsthe eye into the period of fatigue.The procedure recommended isto make a match of colour by varying the height of liquid in theordinary way, as an approximate measure of the height. A slightvariation in height of the standard liquid is then made and anl1 G. Jander and K. F. Weitendorf, Angew. Chem., 1932, 45, 705.la F. Hein and H. Pauling, 2. E'lektrochem., 1932, 38, 25; A,, 243.l3 N. E. Pestov, 2. anal. Chern., 1932, 89, 9;- A., 920.REP.-VOL. XXIX. 226 ANALYTICAL CHEMISTRY.observation is carried out rapidly (about 3 seconds) before the eyehas time to tire.These rapid observations are repeated withslightly different heights above and below the match points andtabulated. I n this way it is possible to ascertain the position ofmatching to 0.2 mm. Certain general considerations are worthy ofnote for accurate work. For each coloured substance there arecertain concentrations and depths of liquid which give the bestresults. For example, in DenigBs's method l4 for determiningphosphoric oxide by formation. of molybdenum-blue, the closestresults are obtained with a concentration of 1-5-26 mg. of P,O,per litre. It is also to be observed that better results are found byusing one eye, in preference to both eyes alternately.Improvements in photoelectric cells, and especially the develop-ment of cells of maximum sensitivity for different parts of thespectrum, point the way to developments in colorimetric determin-ations which should replace the " normal " eye.In this field therecent developments of the boundary-type cells such as the cuprousoxide or the selenium-chromium type offer advantages in facility ofuse, and rapidity and robustness of apparatus. For this kind of cellno external batteries are required. The lay-out is simple : aconstant source of light, a good condensing lens, and a galvanometeror micro-ammeter according to the method of use decided upon.15It is desirable to select a coloured screen, e.g., special green glass,so that a fairly narrow band is cut out of the white light for pro-jection through the test liquid on to the photo-cell.Mr. L. G.Groves and one of the authors l6 have for some time used a cuprousoxide cell covered with a thin film of gold for which the maximumsensitivity to light of colour temperature about 3800" Abs. is inthe green region of the spectrum. Such a cell shows a comparativelylarge change in current for a small change in colour in the regiongreen-yellow, towards either red or blue, and is excellent fortitrations with bromocresol-green or methyl-red indicators. Sincethe response of the photo-cell is very rapid-much less than lo3second-the use of the cell for measuring the depth of colour producedby vitamin A with antimony trichloride is indicated. Usuallythis is determined by means of Lovibond tintometer glass unitsand an endeavour is made t o read maximum intensity. Withthe cuprous oxide cell we find that readings can be takenimmediately after mixing and the rate of variation of the trans-1 4 Compt.rend., 1927, 185, 777; A., 1927, 1156; 1928, 186, 1052; B.,1928, 420.R. H. Muller, Mikrochem., 1932, 11, 353; A . , 1016; H. M. Partridge,I n d , Eng. Chem. (Anal.), 1932, 4, 315; A., 934.16 Unpublished workELLIS AND FOX. 227mitted light can be followed readily wit'h a fairly delicate micro-ammeter. The curve of growth and decay of colour can then beobserved continuously .A further extension for continuous recording purposes is obvious,since the current produced by illurninatlion is ample for applicationto a recording galvanometer of the type made by the CambridgeInstrument Company.Fluorescence Methods of Analysis.-The appearance of a fullsummary of the methods of application of fluorescencef7 to thedetection or characterisation of various substances is opportune inview of the far-reaching claims sometimes made for this method oftest.Perusal of this paper shows that the correct interpretation ofthe fluorescence observed is by no means simple, unless the materialunder test is known and the operator is experienced. The apparatusrequired is simple : a source of ultra-violet light, e.g., a mercury-vapour lamp or metallic arc, an " ultra-violet glass " filter such asWood's ultra-violet glass, which transmits a large proportion ofradiation from about 2800 to 4000 B., and a box to hold the sourceof radiation behind the glass screen.The quantitative utilisationof fluorescence has not yet advanced very far, one difficulty arisingfrom the circumstance that measurement of the int,ensity of fluor-escence is a matter of individual experience. Despite this, someprogress has been made and a few of the results are interesting.The use of the fluorescent " stick '' of J. Eisenbrand l8 is capableof extension. Briefly, this consists in dipping part of a closed tubeof some fluorescent material, say quinine sulphate solution, into theliquid under examination. If the liquid absorbs ultra-violet light,then the part of t'he stick inside the liquid becomes darker than thatoutside and may even become invisible, so that a promising methodof evaluating the concentration of fluorescent liquids is indicated.Many attempts have been made to measure the intensity of thefluorescent radiation, some met hods depending upon examinationof the scattered light as in nephelometric observations, some uponphotometric wedges, and one utilising the standard Guild Colorimeterwhereby the content of red, blue, and green light of the fluorescentsubstance may be reconstituted on a purely physical basis.19Discussion has arisen on the subject of the most suitable concen-tration for quantitative work in fluorescent liquids, and it has beensuggested that a maximum fluorescence occurs at a particular con-centration.The fact seems to be that there is an optimum con-l7 M. Haitinger, Mikrochem., 1932, 11, 429; cf.P. W. Danclcwortt, " Die18 2. angew. Chem., 1929, 42, 445; A., 1929, 666.ID G. E. Troase, Pharm. J . , 1930, 124, 264.Lumineszenz-Analyse im filtrierten ultravioletten Licht," Leipzig, 1929228 ANALYTICAL CHEMISTRY.dition depending upon the mutual effect of absorption of theincident ultra-violet light by the liquid and the resulting fluorescence,and that if a thin enough layer is observed the interference is sodiminished that the fluorescence can be examined t o best advantage.This further indicates that quantitative results will be obtainedbest with the more dilute solutions. Apart from this physical con-dition, the pH of the fluorescent liquid has a large effect on theintensity of fluorescence. Within as little as 0.2 unit of pH as muchas 70% variation in fluorescence has been observed with naphthol-sulphonic acids.20 Prom this fact a necessary precaution is toemploy water buffered to the same pH as the fluorescent solution fordiluting test liquids.I n all attempts t o use the fluorescence arising from the incidentultra-violet light as a quantitative method, it has to be rememberedthat the fluorescence may change owing to photochemical effectspurely, or to the combined effect of light and oxygen.The fadingof the red fluorescence of porphyrin through oxidation is an exampleof this ; 21 the general oxidation occurring during fluorescence withdyestuffs such as eosin and rhodamine, and natural subst,ances likevegetable oils, iesculin, and phloxin, is a subject which has attractedattention from its bearing on the physical condition of thesematerials.22The change of fluorescence with pH is now an established meansof determining by titration very minute quantities of acids or baseswith the aid of ultra-violet light, in many cases with coloured orturbid liquids.While Boyle knew nothing of pH values-and mightconceivably have declined to apply the terminology if he had known-he used an infusion of lignum nephriticum to test for alkalinityand acidity. However, it is satisfactory to note that the method ofusing change, or suppression, of fluorescence for indicator purposesis extending. The important observation of J. Eisenbrand 23 thatquinine has two ranges of inflexion, one at pH 6 and the other atpH 9-5-10, has been utilised by him quantitatively.Strong acidsare indicated very sharply, even in very dilute solutions a t pH 6,whereas weak acids which at first show blue-violet fluorescence, giveno colour a t pH 9.5. A full range of this class of indicator dependingupon fluorescence in ultra-violet light is now available. For ex-ample, eosin can be used t o pH 3, by its green fluorescence ; salicylicacid changes from colourless to dark-blue a t pH 3 ; umbelliferone is2o L. J. Desha, R. E. Sherill, and L. M. Harrison, J. Amer. Chem. SOC.,1926, 48, 1493 ; A., 1926, 996.21 S. Rafalowski, 2. Physik, 1931, 71, 798; A., 1931, 1212.*2 R. W. Wood, Phil. Mug., 1922, [vi], 43, 757; J. C. McLennan, Proc.Roy. SOC., 1923, [ A ] , 102, 256.23 Ph~rm.Z., 1929, 74, 249; A., 1969, 525ELLIS AND FOX. 229especially delicate, changing from colourless to blue in the rangeA few applications of fluorescence or ultra-violet colorimetry t othe detection of elements will serve to illustrate the extraordinaryutility of this field of investigation. Traces of uranium can befound by the yellow fluorescence produced on fusion of the substanceunder examination with sodium fluoride, thus giving a good methodfor use with animal tissues and plant structures. The detection ofarsenic with mercury bromide papers in quantities less than 0.001 yby ultra-violet light is now so well established that it is nearlyin ipossible t o obtain reagents which will not give positive indicationsin these conditions.More recently determinations of cadmium inconcentrations of the order of 1 in 2,500,000 have been carried out,and the details for accuracy defined.25 I n very dilute solution it isdifficult to see cadmium sulphide, and in any case the colour of thissulphide is not suitable for accurate colorimetric use in the ordinaryway; but in ultra-violet light the colour comes out with greatdistinctness. To apply the method t o organic substances, thematerial is oxidised by means of a mixture of sulphuric acid andnitric acid, as in the Kjeldahl process, and the sulphide is precipitatedfrom the resulting solution after suitable treatment in a prescribedmanner.Inorganic Analysis.Organic reagents have been applied to inorganic analyticaloperations for a very long period and several now rank among theclassical methods ; of these may be cited oxalates, tartrates, anddimethylglyoxime.One of the most interesting developments inthe analytical field during the past 10 years or so has been theextension of the application of such substances, and while muchof the work has been carried out on new additions to this class ofreagent, the older ones have not been neglected. Broadly, thesecompounds may be divided into three sections : indicators, reagentsfor colorimetric tests, and those forming insoluble complex com-pounds with metals. Of these, the last are often particularlyadapted to microanalysis on account of their high molecular weightand corresponding low content of the metal.The following account, by no means exhaustive, is intended tosummarise briefly the possibilities of some of these compounds.Xalicylaldoxime, which is readily prepared from the aldehyde,was proposed by P.Ephraim 26 as a precipitant for copper from a24 Y . Volmar and E. Widder, Bull. SOC. chim., 1929, 45, 130.25 L. F. Fairhall and L. Prodan, J . Amer. Chem. Soc., 1931, 53, 1321 ; A . ,36: Re?., 1930, 63, [B], 1928; A., 1930, 1393.PH 6*5-7*6.241931, 701230 ANALYTICAL CHEMISTRY.slightly acetic solution, and separations from various metals wereeffected though 0. L. BradyZ7 found that under the prescribedconditions of acidity, some nickel was also precipitated. I n thepresence of ferric iron, precipitation is best effected in very dilutehydrochloric solution,28 or in the presence of tartrate.29 D.G. Ivesand H. L. Riley 30 used this method to determine the copper in itssalts with certain alkylmalonic acids. The oximes of various otherphenolic aldehydes can also serve to precipitate but possessno advantage over salicylaldoxime. F. Feigl and A. Bondi 32 haveinvestigated the atomic grouping which seems to be more or lessspecific for copper.Benxoinoxirne is another precipitant for copper, t'hough E.Azzalin33 found that it was less satisfactory in the presence ofother metals than was first indicated.34 For copper, it is certainlyinferior to salicylaldoxime, but H. B. Knowles 35 has shown thatmolybdates are completely precipitated by it from quite stronglyacid solutions ; provided vanadates and chromates are first reduced,tungs-hates are practically the only interfering salts and this canreadily be allowed €or by precipitation with ciiichonine from asolution of the mixed ignited and weighed oxides.Dimethylglyoxime gives a pink coloration with ferrous salts onaddition of ammonia 36 which has been applied to the detection ofvanadium.37 The colour is transient owing to the readiness withwhich alkaline ferrous solutions tend to oxidise, but can be pre-served by covering the solution with ligroin.I n connexion withthe better-known use of this reagent for nickel, it may be recordedthat the precipitate can be prepared for weighing by washing withalcohol and ether,3* which, though it has been disputed, wouldappear to be satisfactory provided an adequate current of air is27 J., 1931, 105.28 F.Ephraim, Ber., 1931, 64, [B], 1216; A . , 1931, 813.29 W. Reif, Mikrociienz., 1031, 9, 42.1; A., 1931, 927; 2. anal. Chem., 1932.30 J., 1931, 2003.31 F. Ephraim, Ber., 1931, 64, [B], 1210; A., 1931, 813.32 Ibid., p. 2819; A., 160.33 Ann. Chim. anal., 1925, 15, 373; A., 1926, 140.3 4 F. Feigl, Ber., 1923, 56, [B], 2083; A . , 1923, ii, 880.35 Bur. Stand. J . Res., 1932, 9, 1 ; A , , 1104.36 P. Slawik, Chem.-Ztg., 1912, 36, 54; A., 1912, ii, 299; L. A. Tschugaevand B. P. Orelkin, 2. anorg. Chem., 1914, 89, 401; A., 1915, ii, 489; W.Vauhel, 2. oflentl. Chem., 1921, 27, 163; A., 1921, ii, 596; P. M. Koenig,Chin?. et Ind., 1922, 7, 55; E. J. Kraus, 2. anal. Chem., 1927, 71, 189; A .,1927, 746; 'R. Nakaseko, Mem. CoZZ. Sci. Kyoto, 1928, [ A ] , 11, 113; A , ,1928, 727.88, 38; A., 589.37 F. Ephraini, Helw. Chirn. Acta, 1931, 14, 1266; A., 137." J. Dick, 2. anal. Chem., 1929, 7'7, 354; A., 1929, 901ELLIS AND FOX. 231finally drawn through the crucible ; 39 precipitation in the presenceof much cobalt can be performed by converting that metal intothe form of cobalticyanide, which is not affected by the subsequentaddit'ion of formaldehyde t o reconvert the nickel into the ionisedcondition.40 Among the less common applications may be men-tioned tests for bismuth,41 cobalt,43 and for the platinummetals, in particular palladium.448-Hydroxypuinoline (" oxine ") forms insoluble complex com-pounds with most metals, some of which were known for manyyears before their value in analytical operations was realised byR.Berg and F. L. Hahn independently about six years ago. Sincethat time the publication of well over Mty papers serves to indicatethe interest which this reagent has aroused. The subject has beenreferred t o in recent Reports, but it may be useful to make arecapitulation here.I n his first paperY45 R. Berg presented in tabular form the re-actions of the commoner metals in acetic acid, in ammoniacal, andin caustic alkaline solutions, and showed that in the last case, withtartrate also present, copper, magnesium, zinc, cadmium, andferrous iron alone are precipitated-with the proviso that mercury,bismuth, manganese, cobalt, and nickel are partially precipitatedwhen present in very large proportions.Of this " oxine " group ofmetals, the iron can be eliminated by prior oxidation and all exceptmagnesium are precipitated from acetic solution.The precipitates are crystalline, or can be made so by suitablywarming the solutions, and can readily be filtered and washed.They can be weighed after drying a t an appropriate temperature,usually loo", or often after careful ignition t o oxide, although thisprocedure involves the loss of the advantage of weighing a com-pound of high molecular weight ; for example, the aluminium com-pound contains only 5.87% of the metal. Alternatively, a volu-metric method may be applied whereby the oxine residue is titratedA. A. Wassiljew and A. K. Sinkowskaja, 2.anal. Chem., 1932, 89,262.*O F. Feigl and H. J. Kapulitzas, ibid., 1930, 82, 417; A., 1931, 455.41 H. Kubina and J. Plichta, ibid., 1927, 72, 11; A , , 1927, 1048.43 S. G. Clarke and B. Jones, Analyst, 1929, 54, 333; A., 1929, 900.43 F. Feigl and L. von Tustanowska, Ber., 1924, 57, [B], 762; A., 1924,ii, 504.p4 M. Wunder and V. Thuringer, 2. anal. Chem., 1913, 52, 101, 660; A.,1913, ii, 252, 884; A. Gutbier and C. Fellner, ibid., 1915, 54, 205; A., 1915,ii, 493; A.M. Smoot, Eng. and Min. J., 1915, 99, 700; B., 1915, 554; C. M'.Davis, U.S. Bur. Mines, Rep. Investigations 2351 (1922); A., 1922, ii, 662;H. E . Zschiegner, J . Ind. Eng. Chem., 1925,17, 291; A., 1926, ii, 443; R. A.Cooper, J . Chem. Met. Min. S. Africa, 1925, 25, 296; A., 1925, ii, 827.45 J.pr. Chern., 1927, 115, 178; A., 1927, 674232 ANALYTICAL CHEMISTRY.with standard bromate-bromide mixture ; H. T. Bucherer andF. W. Meier 46 have applied their filtration method in the case ofnickel and cobalt. For small quantities, a colorimetric process hasalso been de~cribed.~'The most useful applications of this reagent are for magnesium 48and aluminium.49 For the determination of the former metal inparticular it has already reached the technical text-books. Theexcess of reagent can readily be removed for subsequent deter-mination of alkali metals, while separation from the alkaline-earthmetals can also be effected, though double precipitation may benecessary. In the case of aluminium, the metal can be precipitateddirectly from solutions which contain organic compounds such astartrates or glycerol which would have to be destroyed before theusual treatment with ammonia could be applied; other usefulseparations are from beryllium,50 and from phosphate, borate,fluoride, uranium, titanium, e t ~ .~ 1Many useful separations of metals can be effected by means ofthis reagent; in addition, it provides a useful means of bringingmetals, which have been separated by other means, into a formsuitable for weighing. Amongst the practical applications whichhave been described are the evaluation of some pharmacopceialsalts and preparations,52 the determination of the magnesium hard-ness of water,53 of magnesium in Portland cement,= in blood 55and in organic liquids, 56 the analysis of cadmium-red pigments46 2.anal. Chem., 1932, 89, 161; A., 1012.4 7 R. Berg, with W. Wolker and E. Skopp, Mikrochem., Emich Festschr.,1930, 18; A,, 1930, 1546; W. A. Hough and J. B. Ficklen, J. Amer. Chern.SOC., 1930, 52, 4752; A , , 1931, 327.R. Berg, 2. anal. Chem., 1927, 71, 23; A., 1927, 639; F. L. Hahn andK. Viewig, ibid., p. 122; A., 1927, 639; H. Fredholm, Svensk Kem. Tidskr.,1932, 44, 79; A., 489.49 R. Berg, 2. anal. Chem., 1927, 71, 369; A., 1927, 848; F. L. Hahn andK. Viewig, loc. cit. (ref. 48).5O I. M. Kolthoff and E. B. Sandell, J. Amer. Chem. SOC., 1928, 50,1900; A., 1928, 981; M. Niessner, 2. anal. Chem., 1929, 76, 135; A., 1929,285.51 G. E. F. Lundell and H. B. Knowles, Bur. Stand. J. Res., 1929, 3, 89;A., 1929, 1260.s2 H.Matthes and P. Schutz, Pharm. Ztg., 1928, 73, 353; B., 1928, 501 ;I. M. Kolthoff, ibid., 1927, 72, 1173.53 K. V. Luck and H. J. Meyer, 2. angew. Chem., 1928, 41, 1281; B., 1929,114; M. E. Stas, Pharm. Weekblad, 1930, 67, 1245; B., 1931, 92.54 J. C. Redmond and H. A. Bright, Bur. Stand. J. Res., 1931, 6, 113; B.,1931, 396.65 S. Yoshimatsu, Mikrochem., 1931, 9, 628; D. M. Greenberg and M. A.Mackay, J. Biol. Chem., 1932, 96, 416; A . , 764.56 C. Bomskov, 2. physiol. Chem., 1931, 202, 32; A., 35ELLIS AND FOX. 233involving separation of cadmium from ele en ate,^^ and its use insilicate analysis.58Following the observation 59 that 5; : 7-dibromo-8-hydroxyquinol-ine gives a precipitate with copper salts even in mineral acid solu-tion, the influence of various substituents on the solubility andstability of the complex metal compounds has been investigated.60’ Several of the 5 : 7-dihalogeno-derivatives form very insolublecompounds with copper, iron, and titanium, for which metals ascheme of separations has been described, based on the dibromo-derivative .61Aliphatic diamines, e.g., ethylenediamine, form certain insolublecomplexes such as (HgI,)(Cuen,), which has been applied to thedetermination of both mercury 62 and copper.63 Cadmium formsan analogous but in the case of bismuth, the cobaltcomplex has the composition (BiI,),(Co en,)I G5 (compare the com-pound CgH70N,HBi14 given by bismuth with 8-hydroxyquinolinein the presence of iodide).66 Propylenediamine can also be used inthe mercury-copper complex.67A compound of somewhat different character is (Ni en,)S,O,,whose insoluble character permits the detection of thiosulphate inthe presence of most sulphur oxy-acids, thiocyanate, and sodiumsulphide ; 68 this recalls the compound copper pyridine persulphatewhich serves to detect pers~lphate.~~DiaZEyZdiMiocccrbamtes, which were proposed many years ago 70for the detection of copper and iron, have been applied quantitat-ively to the determination of copper, 71 sodium diethyldithiocarb-G 7 C. G. Daubney, Analyst, 1932, 57, 22; B., 234.5 8 J. Robitschek, J. Arner. Ceram. SOC., 1928, 11, 587; B., 1928, 895;A. Benedetti-Pichler and F. Schneider, Mikrochem., Emich Festschr., 1930,1 ; A., 1930, 1544; A.Granger, Ceram. et Verrerie, 1932, 137.50 R. Berg, Z . anal. Chem., 1927, 70, 341; A., 1927, 436.6O Idem, Z . anorg. Chem., 1932, 204, 208; A . , 490.61 R. Berg and H. Kustenmacher, ibid., p. 215; A., 490; see also idem,Mikrochem., Emich Festschr., 1930, 26; A., 1930, 1546; V. Marsson andL. W. Haase, Chem.-Ztg., 1928, 52, 993; A., 1929, 164; L. W. E a s e , Z .anal. Chem., 1929,78, 113; A., 1929, 1159.G2 G. Spacu and G. Suciu, ibid., 1929, 77, 334; 78, 244; A., 1929, 901,1259.63 Idem, ibid., p. 329; A., 1929, 1413.64 Idem, ibid., p. 340; A., 1929, 900.65 Idem, ibid., 79, 196; A., 1930, 184.M R. Berg and 0. Wum, Ber., 1927, 60, [B], 1664; A., 1927, 847.87 G. Spacu and P. Spacu, Z. anal. Chem., 1932, 89, 187; A., 1011.69 G. Spacu, But.SOC. StGnte Cluj, 1923, 1, 583.70 M. DelBpine, Bull. SOC. chim., 1908, [iv], 3, 652; A., 1908, ii, 633.71 T. Callan and J. A. R. Henderson, Analyst, 1929, 54, 650; A.,Idem, ibid., p. 192; A., 1010.1930, 53.H 234 ANALYTICAL CHEMISTRY.amate being the particular salt used. Since iron also gives abrown colour, it must be removed, and this has been effected byelectrolytic deposition of the copper 72 or by means of citric acid; 73the coloured copper salt can then be extracted by carbon tetra-chloride. The method has been applied to ascertain the coppercontent of sea-water 74 and of certain pharmaceutical preparationsand chemicals. 75 Piperidine pentamethylenedithiocarbamate, pre-pared commercially as an accelerator for vulcanisation, can be usedfor the same purp0se.7~Tetramethyldiaminodiphenylmethane (" tetramethyl-base ") haslong been known as a reagent, qualitatively, for ozone 77 and forlead and manganese in their higher states of oxidation.78 Althought'he blue coloration is not too stable, endeavours have been made toutilise the reaction quantitatively for lead 79 and for manganese ;permanent standards are prepared of mixtures of crystal-violet andmethylene-blue.New ground is cut in reactions with vanadateand tungstate, the latter being applied quantitatively.81Cupferron, which derived its name its a precipitant for copperand iron, is also known in the same capacity for titanium andzirconium ; during t,he last ten years, furt<her investigations haverevealed other possibilities, in particular in the case of tin.82 Con-ditions for the precipitation of mercurous mercury 83 and bismuth **are also described.It must not be overlooked that, in neutralsolution, all metals except the alkalis are precipitated by cupferron72 F . Grendel, Pharm. Weekblad, 1930, 67, 913, 1050, 1345; B., 1930,1089; W. R. G. Atkins, J . Marine Biol. ASSOC., 1932, 18, 193; A., 714.73 L. A. Haddock and N. Evers, Analyst, 1932, 57, 495; A., 1011.7 4 W. R. G. Atkins, loc. cit. (72).7 5 N. Evera and L. A. Haddock, Quart. J . Pharm., 1932, 5, 458.7 6 R. G. Harry, AnaZyst, 1931, 56, 736; A., 35.7 7 C . Arnold and C. Mentzol, Ber., 1902, 35, 1324; A., 1902, ii, 352; F.Fischer and F . BrBhmer, Ber., 1906, 39, 940; A., 1906, ii, 224; F.Fischerand H. Marx, ibid., p. 2555; A , , 1906, ii, 627.78 J. A. Trillat, Compt. rend., 1003, 136, 1205; A., 1903, ii, 512; J. B .Ficklen, Chem. and Ind., 1931, 50, 869; A., 1931, 1383.79 A. D. Petrov, J . Buss. Phys. Chem. SOC., 1928, 60, 311; A . , 1928,726.R. G. Harry, Chem. and Ind., 1931, 50, 796; A , , 1931, 1385.M. Papafil and R. Cernatesco, Ann. sci. Univ. Jassy, 1931, 16, 526;A., 1931, 1386.82 A. Kling and A. Lassieur, Compt. rend., 1920, 170, 1112; A , , 1920, ii,452; N. H. Furman, J . I n d . Eng. Chem., 1923, 15, 1071; A., 1923, ii, 881;A. Pinkus and (Mlle.) J. Claessens, Bull. SOC. chim. Belg., 1927, 36, 413; A . ,1927, 848.83 A. Pinkus and (Mlle.) M. Katzenstein, ibid., 1930, 39, 179; A., 1930,1011.a. Pinkua and J. Dernies, ibid., 1928, 37, 267; A., 1928, 1109ELLIS AND FOX. 235and that such separations depend upon the varying solubilities ofthe salts in acid solutions.a-Nitroso-~-mphthoZ is best known as a precipitant for cobalt,s5although it has also been applied to the determination of palladium 86and to the separation of iron from beryllium,87 indium,s8 andgalli~rn.~S Since cupferron does not interfere with the subsequentprecipitation of cobalt by nitrosonaphthol, the former reagentcan be used t o remove traces of iron left after ether extractionin the determination of cobalt in magnetic and high-speed tools teeL90One of the drawbacks to the use of this reagent for cobalt is thatthe precipitate obtained is of indefinite composition and musttherefore be subjected to further treatment to convert it into aform suitable for weighing.It has now been shown,g1 by firstoxidising the cobalt and then working in an acetic acid solution ofthe cobaltic hydroxide obt,ained on addition of alkali, that a definitecompound is obtained which can be dried a t 130" without losingits two molecules of water. The process is particularly applicableto the analysis of cobaltic colours such as smalt.An interesting test for cyanates,92 applicable in the presence ofmost inorganic salts, consists in t,reating the dried silver salt,suspended in ether, with cyclohexene and iodine; the pungent-smelling 2-iodocycZohexylcarbimide is formed. As cyanides alsocause the formation of a somewhat similar-smelling compound,treatment of the test solution with ammonia to give a white, finelycrystalline precipitat,e of the corresponding carbamide serves t odiagnose cyanates.The readiness with which sodium sulphite in solution becomesoxidised is not generally appreciatcd: Experiments a t concen-trations such as are used in volumetric work have showns3 thatsuch oxidation may amount to 30% in 30 minutes, but may beretarded for some hours by the addition of erythritol, glycol, orethyl alcohol.In the case of sulphurous acid there is the additional85 M. Ilinski and G. v. Knorre, Ber., 1885, 18, 699; A., 1885, 840.8 6 M. Wunder and V. Thiiringer, 2. anal. Chem., 1913, 52, 737; A., 1913,ii, 1080; W. Schmidt, 2. anorg. Chem., 1913, 80, 335; A., 1913, ii, 440.87 M. Schleier, Chem.-Ztg., 1892, 16, 420; B., 1892, 713; E.A. Atkinsonand E. F. Smith, J . Amer. Chrn. SOC., 1895, 1'7, 688; A., 1896, ii, 220.8 8 F. C. Mathers, ibid., 1908, 30, 209; A., 1908, ii, 434.89 J. Papish and L. E. Hoag, ibid., 1928, 50, 2118; A., 1928, 981.01 C. Mayr and F. Feigl, 2. anal. Chem., 1932, 90, 15; A , , 1224.92 M. Linhard and M. Stephan, 2. anal. Chem., 1932, 88, 16; A., 588.g3 J. Lukas, Chem. Listy, 1932, 26, 26; A., 242.See p. 221236 ANALYTICAL CHEMlSTRY.danger of loss of sulphur dioxide although these errors may bereduced by the use in the analysis of a stronger oxidising agentthan the usual iodine.94 I n general terms, acid sulphite solutionsare more stable than neutral solutions.95 These considerationsalso enter into determinations of sulphur dioxide in gases; thusM.D. Thomas and J. N. Abersoldg6 found that substantial pro-portions of the dioxide absorbed in water from very dilute mixtureswith air were oxidised. It follows that accurate determinationsof the dioxide in gaseous mixtures can only be made if thescrubbing reagent can serve as the oxidising agent, e.g., hydrogenperoxide or iodine-starch, or, if alkaline media are used, somestabilising substance such as has been mentioned above is alsopresent ; for tjhis purpose H. F. Johnstone 97 found benzyl alcoholsatisfactory.The iodometric determination of persulphate has attracted muchattention in recent years, and, although reports have, on the whole,been favo~rable,~~ yet erratic results have been recorded ; 99 thesehave now been traced to the presence in the potassium iodide of asmall quantity of organic impurity having a strong reducing actionin alkaline solution.Persulphates, including the ammonium salt,are decomposed by boiling for a short time with excess of pureneutral hydrogen peroxide, and the sulphuric acid formed can thenbe titrated with alkali.2Organic Analysis.Compounds having an enolic or allied structure have a reducingaction on mercurous nitrate; the reaction is more general thanthat with ferric chloride but is also given by certain substanceshaving active unsaturated grouping^.^During recent years, many derivatives have been described forthe purposes of identification of numbers of various classes ofcompound. In the case of acids, particular attention has beenQ4 J.Bicskei, 2. anorg. Chem., 1927, 160, 64; A., 1937, 330.O 5 H. M. Mason and G. Walsh, Analyst, 1928, 53, 142; A., 1928, 497.9 G Ind. Eng. Chem. (Anal.), 1929, 1, 14; B., 1929, 282.Q7 Univ. Illinois Bull., 1931, 28, No. 41, 100.Q8 L. von Zombory, 2. anal. Chem., 1928, 73, 217; A,, 1928, 497; A.Schwicker, ibid., '74, 433; A., 1928, 1107; C. V. King and E. Jette, J. Amer.Chem. SOC., 1930, 52, 608; A., 1930, 441; J. H. van dor Meulen, 2. anal.C'hem., 1932, 88, 173; A., 710.Q9 A. Kurtenacker and H. Kubina, ibid., 1931, 83, 14; A., 1931, 451.1 A. Kurtenacker, ibid., 88, 171 ; A., 710.3 E. V. Zappi, Bull. SOC. chim., 1932, [iv], 51, 54; A., 362.J. H. van der Meulen, Rec. trav. chim., 1932, 51, 445; A., 587ELLIS AND FOX. 237paid to the phenacyl4 and substituted phenacyl esters.Duringthe present year the lists have been extended in the case of theunsubstituted,6 the p-halogeno-,' and p-phenyl-phenacyl esters.I n general, aliphatic acids when warmed with thionylaniline affordanilides .92 : 4-Dinitrochlorobenzene readily reacts with alkyl and arylsodium mercaptides to form sulphides which in turn may be con-verted into the corresponding sulphones by means of permangan-ate.lO The p-toluenesulphonates of aromatic amines can, in general,bc readily prepared in a pure state ; l1 the p-nitrobenzyl derivativesof a number of amines have been described,12 and the carbamatesand carbamides derived from p-nitrophenylcarbimide with alcoholsand amino-compounds.13Pentabromoacetone, formed by the oxidation of citric acidby acid permanganate in the presence of bromide, reacts inalcoholic solution with sodium iodide; one molecule of citricacid in this way liberates six equivalents of iodine.This methodis more rapid than those in which the bromo-compound isweighed.14The claim by L. Nyns l5 for a copper-bicarbonate solution asspecific for fructose has been disproved both in this country and inAmerica. Maltose, dextrose, and arabinose reduce the reagent to aslight degree, the effect increasing in the order given. Nevertheless,the method is of value in sugar analysis, particularly when used incombination with other methods; by working a t 55" instead of at48-549", the period of reduction may conveniently be reduced by$. B. Rather and E. E. Reid, J . Amer. Chem. SOC., 1919, 41, 75; A.,1919, i, 157.W. L. Judehd and E. E. Reid, ibid., 1920, 42, 1043; A., 1920, i, 480;R. M. Ham, E. E. Reid, and G. S. Jarnieson, ibg., 1930, 52, 818; A., 1930,474; S. G. Powell, ibid., 1931, 53, 1172; A., 1931, 621; N. L. Drake andJ. Bronitsky, ibid., 1930, 52, 3715; A., 1930, 1436.13 K. Chen, Trans. Science SOC. China, 1931, 7, 73; A., 529; W. Kimura,J. SOC. Chem. Ind. Japan, 1932, 35, 221; A., 946.7 K. Chen and C. Shih, ibid., p. 81 ; A., 529; C. G. Moses and E. E. Reid,J. Amer. Chern. SOC., 1932, 54, 2101; A., 744; H. Lund and T. Langvad,ibid., p. 4107; A., 1249.* N. L. Drake and J. P. Sweeney, ibid., p. 2059; A., 745.10 R. W. Bost, J. 0. Turner, and R. D. Norton, J. Amw. Chem. SOC., 1932,l1 C. R. Noller and P. Liang, ibid., p. 670; A., 375.l2 E. Lyons, J. Amer. Pharm. ASSOC., 1932, 21, 224; A., 502.l3 C. W. van Hoogstraten, Rec. trav. chim., 1932, 51, 414; A., 597.l4 P. A. Kometiani, 2. anal. Chem., 1931, 86, 359; A., 43.P. Cam6 and D. Libermann, Compt. r e d . , 1932,194, 2218; A., 867.54, 1985; A., 719.Sucr. Belge, 1924, 44, 210; B., 1925, 21238 ANALYTICAL CHEMISTRY.one-half, i.e., to 75 minutes.16 Both phenolphthalein and alcoholreact with iodine in the presence of alkali; in neutralising solutionsprior to the oxidation of aldose sugars by alkaline iodine, the useof aqueous methyl-orange avoids the introduction of errors fromthis cause.17Conditions are described for the quantitative determination ofvarious carbonyl compounds by formation of 2 : 4-dinitrophenyl-hydrazones; the method has been applied to camphor, menth-one, pulegone, citral, furfuraldehyde, methylfurfuraldehyde, andsant onin.B. A. ELLIS.J. J. Fox.16 E. F. Jackson and J. A. Matthews, Bur. Stand. J. RCS., 1932, 8, 403;17 (Miss )C. A. Mallen, AnaZyst, 1932, 57, 244; A . , 603.Is 0. Fernjndez, L. Sociiis, and C. Torres, AnaZ. Pis. Quim., 1932, 30,37 ; A., 411 ; 0. Fernandez and L. SociAs, ibid., p. 477 ; A . , 948 ; E. Simon,Biochem. Z., 1932, 247, 171; A., 763.A . , 836

ISSN:0365-6217    

DOI:10.1039/AR9322900220

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

BIOCHEMISTRY.CONTINUED interest in the chemistry of the vitamins, and theconsiderable advances achieved during the past year, justify theattention which is again given to this field. Of outstanding inter-est, too, is the development of the recent work on the secondarysex hormones, more especially in relation to the striking advancesin the chemistry of the cholane series. Of the other subjects dealtwith this year in the section of animal biochemistry, particularattention is directed to the new and promising work on urea form-ation in the liver, and to the progress made in the investigation ofcarcinogenic hydrocarbons.In the section of plant biochemistry the general arrangement ofthe last Report has been retained. Undiminished interest in themineral nutrition of plants is again apparent, and the steadyadvancement in the elucidation of the varied metabolic processesof moulds is continued.A section dealing with certain plantenzymes and their activation is necessitated by the activity ofworkers in this field. The admirable work of R. and G. M. Robin-son on the anthocyanin pigments marks a very great advance inthis subject. The scope of the published work is too wide foradequate treatment here and reference to detail should be madein the original papers.ANIMAL BIOCHEMISTRY.Secondary Sex Hormones.The last few years have witnessed a steadily increasing activityin t,he investigation of the internal secretory products responsiblefor the control of the'development of the secondary sex charactersof the male and the female animal.In particular, during the pastyear, considerable advances have been made in the elucidation ofthe structures of these interesting substances. These advancesare mainly due to the new structural conception of the cholaneseries (bile acids and sterols) introduced by 0. Rosenheim andH. King and developed by them 2 and by the German workers,notably H. Wieland and E. Dane.3 At the time of writing itseems clear that two substances, or types of substance, have beenreasonably well characterised. The first of these is the follicularhormone which in animals produces oestrous, and influences thegrowth and course of development of the secondary female sex1 J . SOC. Chern. Id., 1932,51, 464.3 2. physiol. Chem., 1932, 212, 41, 263.Ibid., p.954340 BIOCHEMISTRY.characters. It is also claimed that this substance accelerates theformation of flower and fruit buds in plant^,^ and it has been statedthat the hormone, or substances closely resembling it in structureand properties, may be obtained from plant sources. Thus, acrystalline substance of this type has been isolated from palm-kernel extracts.5 The second sex hormone is the testicular hormoneisolated in a crystalline condition from male urine. It wouldappear to be closely related structurally to the follicular hormoneand it is suggested that both have the same basal constitution asthat of t'he members of the cholane series, namely, a tetra-nuclearstructure comprised of a three-ring phenanthrene system with anadditional five-membered ring.The FoZZicuZar Hormone.-In the Reports for the last two yearsthe isolation and initial steps in the investigation of this hormonehave been recorded.It has now become possible, in view of thenewer work on the cholane series, to suggest a structure for thehormone and for the related inactive alcohol, pregnandiol, isolatedalong with the hormone from the urine of pregnancy. A. Buten-andt suggests that many substances with a similar hormoneactivity and closely related to one another may exist, but on thebasis of present work it is clear that the most important are thea-follicular hormone (ketohydroxyoestrin, C,,H,,O,) and its hydrate(trihydroxyoestrin, C,,H,,O,). The investigations of Marrian andof Butenandt and their respective colleagues have led to thefollowing conclusions.The hydroxy-ketone is formed from thehydrate by loss of water from two neighbouring hydroxyl groups.The third hydroxyl is acidic. Catalytic hydrogenation yields ahexahydro-derivative in the form of a saturated hydrocarbonC&,O. Zinc distillation yields the aromatic hydrocarbon C18H1,.The three double bonds inferred t o be present are in the same ringand this also carries the acidic hydroxyl, whereas the alcoholichydroxyls of the hydrate are in a saturated ring. It is thereforesuggested that the hormone is a condensed system consisting of abenzene ring and three saturated rings. X-Ray crystallographicmeasurements by J. D. Berna1,lo and an investigation of unimole-* W.Schoeller and H. Goebel, Biochem. Z., 1932, 251, 223; A., 1068 (seealso A., 1931, 1337).A. Butenandt, Angew. Chem., 1932, 45, 655.Ann. Reports, 1930, 27, 271 ; 1931, 28, 236.LOG. cit. See also A. Butenandt and I. Stomer, 2. physiol. Chem., 1932,208, 129; A., 781.G. F. Marrian and G . A. D. Haslewood, Biochem. J., 1932, 26, 25; A.,655.LOG. c i t . See also Nature, 1932, 130, 238; .4., 971.lo J. SOC. Chem. Ind., 1932, 51, 269POLLARD AND PRYDE. 241cular surface films by N. K. Adam and his colleagues,ll and byJ. F. Danielli l 2 show that the saturated ring carrying the ketonicgroup and the benzene ring carrying the acidic hydroxyl are atopposite ends of the molecule.The facts outlined in the foregoing are expressed in the formuhappended.(I) is the hydrocarbon C,,H,,, (11) is. ketohydroxy-oestrin, C18H2202, first obtained by Butenandt, and (111) is tri-hydroxyoestrin, C,,H2,0,, first obtained by Marrian.Me Me(1.1 (11.1 (111.)Testiculur IIormone.-This hormone in a crystalline state hasbeen obtained by A. Butenandt 13 (with K. Tscherning) from maleurine. Its isolation from testes is also claimed in an earlier com-munication by B. Frattini and M. Maino,14 whose preparation wasless well characterised and probably much less pure than that ofButenandt.15 The testicular substance is closely related to thefollicular hormone and is also a hydroxy-ketone. It is saturatedand possesses no acidic properties. Its melting point is given as178" and its composition is C18H2,02 or C,,H,,O,, although itshomogeneity is still in doubt.Butenandt 16 has tentatively sug-gested the formula (IV). Its activity would seem to be of a highorder, since a total quantity of 1 to 1.2 y administered in four dosesover a period of two days produced a 30-35% increase in combgrowth in cocks.Me Me Me0UV.1 (V.) Pregnandiol (VI.) CI,H,,O, Alcohol11 N. K. Adam, J. F. Danielli, G. A. D. Haslewood, and G. F. Marrian,l2 J . Soc. Chern. Ind., 1932, 51, 1075.13 LOG. cit.14 Arch. 1st. biochim. ital., 1930, 2, 639; A., 1931, 398.Biochem. J., 1932,26, 1233; A., 1173.See also 2. angew. Chern., 1931, 44, 906; A., 96.See also Bwchern.Z., 1932,258, 202; A., 1173.16 Angew. Chem., 1932,45, 324; A,, 781. 16 LOG. cit242 BIOCHEMISTRY.The Origin of the Xex Hormones.-The present state of the in-vestigations just outlined leads to the conclusion that the sexhormones are oxidation products of the bile acids and sterols, theprocess involving the breakdown of side chains and the conversionof a saturated into an aromatic ring with associated loss of a methylgroup (compare the conversion of ergosterol, C,,H,O, into neo-ergosterol, C27H,00).17 This view of the relationship of the sexhormones to the cholane series gains in probability from the isolationof pregnandiol, C21H3602, together with two other inactive pro-ducts, an alcohol, C1,H,,O2 (m.p. 232"), and a hydroxy-ketone(m. p. 176.5") isomeric with the testicular hormone. These sub-stances, for which the formuh (V) and (VI) are suggested, mayreadily be fitted into the general scheme as intermediate steps inthe biological formation ol the active products.G. F.Marrian and G. A. D. Haslewood18 have recorded theisolation from pregnant mare's urine of a dihydroxyphenol,C,,H,,O(OH),, m. p. 189-190*5", to which they have given thename equol. It is physiologically inactive. If this compound isrelated to those already discussed, it would seem to be a derivativein which the three-ring phenanthrene nucleus alone persists withone additional carbon, but at the time of writing evidence of therelationship of equol to previously described compounds is lacking.Isomeric Follicular Ho7mones.-Reference has already been madeto the possible existence of closely related substances with similarhormone activities.A. Butenandt and I. Stormer l9 state that,when water is eliminated from trihydroxyoestrin by distillationover potassium hydrogen sulphate, there are formed 01- and p-hydr-oxy-ketones which form mixed crystals and are both physiologicallyactive. The a-isomeride is the original hormone of Butenandt, andthe existence of the two forms is ascribed to a cis-trans isomerism.E. Schwenli. and F. Hildebrandt 2o have isolated from mare's urinea further isomeride for which they claim a physiological activityhigher than that of the a-hormone of Butenandt. A. Girard andhis collaborators 21 have also described isomeric crystalline prepar-ations isolated, in addition to the a-hormone, from mare's urine.These appear to have an oestrogenic activity about one-eighth thatof the a-follicular hormone. Whether these substances are pureisomeric hormones of lower physiological act'ivity, or mixed crystalsof active and inactive components, remains an open question, but1' H.H. Inhoffen, Annalen, 1932,497, 130.20 Natumuiss., 1932, 20, 658; A., 1173.21 A. Girard, G. Sandulesco, A. Fridenson, and I. J. J. Rutgers, Compt. rend.,18 Biochem. J., 1932, 26, 1227; A., 1156. 19 L O C . cit.1932,194,909, 1020; A., 433, 547POLLARD AND PRYDE. 243there seems t o be little doubt concerning the existence of isomeridesin this interesting group of substances.A Substance Present in the Testicle which Increases TissuePermeability,F. Duran-Reynals in 192822 and 192923 described a testicularextract which much increased the lesions produced by intradermalinoculation of vaccine virus.D. hlcClean z4 made further observ-ations on this interesting substance, and showed that it increasedthe permeability of the dermis so much that the bleb following theinjection immediately disappeared and the inoculum diffused throughan increased a'rea of the dermis, Extracts of spermatozoa were shownt o possess the same activity as extracts of the whole testicle. Thissuggested that the phenomenon is connected with the germinalactivity of the testicle and is not a fortuitous property of the inter-stitial tissue of the gland. A possible association of the activesubstance with the sudden change in the permeability of the ovaon fertilisation was suggested. W.T. J. Morgan and D. McClean 25have now described the purification of the active testicular extracts,and the preparation of a highly active dry material. The latterhas [.ID - lo", nitrogen lo%, and amino-nitrogen 1.5%. TheMolisch test is negative and all protein tests are positive. Theactive substance is not adsorbed from aqueous solution by benzoicacid. The minimal dose producing definite diffusion in the skin ofthe rabbit is 0.00001 milligram.Secretin.During the past year two papers dealing with the preparationand chemical properties of secretin have appeared. In 1928,J. Mellanby26 described a method for preparing the hormonesecretin which gave a product free from the depressor substancealways present in acid extracts of the duodenal mucosa. He nowdescribes an improved and simpler method : 27 the product containsC, 49.1; H, 6.9; N, 13.8; S, 1.5; ash, 1.17; 0 (by difference),28.6%, but no phosphorus.These figures, together with thephysical properties of secretin, suggest to Mellanby that secretinis a polypeptide. It is rapidly destroyed by trypsin-kinase, but isnot acted upon by enterokinase or by trypsin in freshly secretedpancreatic juice. The yield is about 10 milligrams from 500 gramsof intestinal mucosib. Secretin does not dialyse from aqueous22 Compt. rend. SOC. Biol., 1928, 99, 1908.2s J . Exp. Med., 1929, 50, 327.24 J. Path. Bact., 1930, 33, 1045; 1931, 34, 459.25 J. SOC. C h m . Ind., 1932, 51, 912.47 Proc. Roy. SOC., 1932, [B], 111, 429; A.: 1171.26 A., 1928, 1403244 BIOCHEMISTRY.solution through a collodion membrane.Its physiological actionsare : (1) the production of a large volume of pancreatic juice;(2) the contraction of intestinal muscle; (3) the secretion of asmall qxantity of bile.A paper by R. N. Cunningham 28 also describes the preparationof secretin free from depressor substances, insoluble proteins, andinorganic salts. Cunningham’s conclusion is that secretin is asecondary proteose. It passes through cellophane, but is retainedby collodion membranes permeable to peptones. The results ofMellanby and Cunningham are, therefore, subst antially in agree-ment, especially in regard to the peptide structure of their respectivematerials. There is, howcver, some divergence of opinion regardingthe molecular dimensions of secretin.Urea Formation in the Animal.An important paper by H.A. Krebs and K. Henseleit 29 dealingwith the formation of urea in the animal body opens up new aspectswhich may well prove to be fundamental. The authors havestudied the rate of synthesis of urea from carbon dioxide andammonia in surviving tissue sections of rat’s organs. The methodsemployed reveal the liver as the sole organ in which this synthesisoccurs, and in this organ the rate of synthesis is greatly increasedby the presence of ornithine. This amino-acid acts as a catalyst,since it is not used up and small amounts effect a large synthesis.Similar results are obtained with arginine in virtue of its conversioninto ornithine in the liver.On the othcr hand no increased urcaformation was observed in the presence of glycine, dl-alanine,d-valine, Z-leucine, d-cysteine, asparagine, aspartic acid, glutamicacid, phenylalanine, tyrosine, putrescine, cadaverine, lysine, creatine,guanidine, choline, tryptophan, or histidine. Apart from ornithineand arginine, the only other amino-acid effective in producingincreased urea synthesis is citrulline. This acid was isolat’ed byY. Koga and S. Odake 3O in 1914 from the water melon (CitruEEusvulgaris). Its constitution was established by M. Wada31 bysynthesis. It is a-amino- 8-carbamidovaleric acid,NH,*CO*NH*CH2*CH2*CH2*CH( NH,)*CO,H.Its formation has been observed by D. Ackermann 32 when arginineis acted on by putrefactive bacteria in a suitable medium, and in28 Biochem. J., 1932, 26, 1081; A., 1171.29 2.physiol. Chem., 1932, 210, 33; A., 1059.30 J. Tokyo Chem. Soc., 1914, 35, 519.31 Proc. Imp. Acad. Tokyo, 1930, 6, 15; A., 1930, 1224.33 Z. physiol. Chern., 1931, 203, 66 ; A., 196.See also Biochcrn.Z., 1930, 224, 420POLLARI) AND PRYDE. 245general the formattion of carbamido-acids from amino-acids is awell-established biological process.33In accelerating urea formation citrulline is consumed in theprocess and furnishes one atom of nitrogen per molecule of urea.The respective actions of ornithine and citrulline in promoting ureasynthesis in the liver are explained by Krebs and Henseleit asfollows : (1) The formation of citrulline by the condensation ofone molecule of ammonia and one of carbon dioxide with the6-amino-group of ornithine; (2) the condensation of one moleculeof citrulline with a second molecule of ammonia to form arginine;(3) the decomposition of arginine by arginase to form ornithineand urea.NH2*[CH2],*CH(NH2)*CO2H + NH3 + CO,IOptimal formation of urea in the liver sections is observed in thepresence of 10 mg.per cent. of d-ornithine and 200 mg. per cent.of dl-lactate. Urea is not formed in liver pulps in which the cellstructure is destroyed, and although its synthesis does not involvean increased oxygen consumption by the liver, the process is closelydependent upon respiration. It is of interest to note, in view ofthe currently accepted structural relationship of urea to ammoniumcyanate, that the latter does not increase the urea formation in theliver.The next step in this interesting series of investigationswould appear t o be the attempted isolation of citrulline, or a suit-able derivative, from a liver preparation actively forming urea.D. Ackermann% has failed t o observe the fission of arginine intocitrulline and ammonia on subcutaneous injection of arginine intoa dog. Nor was this process observed in ox liver, kidney, muscle,spleen, goose liver, or liver and muscle of the crayfish. It will,however, be borne in mind that this conversion is the reverse ofthat postulated by Krebs and Henseleit.These new observations are obviously of the greatest importance,but it must not be forgotten that the animal does not form urea fromammonia but from amino-acids, and it has not been possible, sofar, t o correlate the deaminisation process with ammonia production.33 H.D. Dakin, J . Biol. Chem., 1909, 6, 240.34 2. physiol. Chem., 1932, 200, 12; A., 9G2246 BIOCHEMISTRY.Dyes and Urease.I n the Report of last year reference was made to the suggestivework of J. H. Quaste135 on the toxic action of dyes and relatedcompounds on various enzymes. These investigations have nowbeen extended to u r e ~ s e . ~ ~ In general it is found that acidic dyesare entirely inert and that most basic dyes are toxic. The toxicityof such dyes as brilliant-green is enhanced by substances, appar-ently of the nature of the unsaturated glycerides, present in soya-bean oil, which act as highly specific mordants between urease andthe basic triphenylmethane dyes.Urease may be protected fromthe t'oxic action of the various dyes by urea, a-amino-acids, sar-cosine, et hylenediamine, met hylamine, dimet hylamine, hydrazine ,and hydroxylamine. No protection is afforded by trimethylamine,betaine, urethane, methylurea, diethylurea, and oxamic acid. Ofparticular interest is the observation that potassium cyanate pro-tects urease from the toxic action of brilliant-green, whereasammonium carbamate has little or no effect. The underlyingtheory being that protection indicates a combination between theenzyme and the protective substance, this observation is evidencefor the contention that cyanic acid, rather than carbamic acid, isproduced from urea by urease.It should, however, be noted thatsodium cyanate is entirely without protective action against toxicdyes.Carcinogenesis by Pure Hydrocarbons.The varied physiological activity of the cholane series and relatedpolycyclic compounds lends added interest to an already interestingproblem, the production of cancerous new growths by applicationto the skin of pure polycyclic hydrocarbons. That hydrocarbonscan produce cancer in mice followed from the work of E. L. Kenna-way,37 who investigated the carcinogenic mixtures, which couldconsist only of hydrocarbons, produced by heating acetylene orisoprene in an atmosphere of hydrogen. The strong fluorescenceof these and of other carcinogenic mixtures well recognised inmedical practice (e.g., gasworks tar, shale oil, heated petroleum,and products of the action of heat on various substances of bio-logical origin such as cholesterol, yeast, skin, muscle, and hair)suggested that such hydrocarbons were of the polycyclic aromatictype.5. W. Cook, I. Hieger, E. L. Kennaway, and W. V. May-neord 38 have prepared and examined the following compounds,35 Ann. Reports, 1931, 28, 226.36 J. 13. Quastel, Biochem. J., 1932, 26, 1G85.3 7 J . Path. Bact., 1924,27, 234; Brit. Med. J., 1925, 2, 1 ; Biochem. J., 1930,38 PTOC. Roy. Xoc., 1932, [ B ] , 111, 455; A., 1166.24, 497; A., 1930, 807POLLARD AND PRYDE. 247composed entirely of condensed benzene rings, with the view ofascertaining their carcinogenic action if any : (I) all the six possible4-ring compounds; (2) all the ten known compounds out of thefifteen possible 5-ring compounds ; (3) some compounds containingsix and eight rings, and others.The work has been extended byJ. W. Of these compounds it is found that 1 : 2 : 5 : 6-dibenzanthracene (I) 4O alone shows carcinogenic power. It retainsthis undiminished even when very highly purified; thus, it hasbeen shown t o be active in nine different media, and has producedcancer when applied to the skin of mice in a concentration of 0.00370in benzene. Less active are its 2’-methyl, 3’-methyl, 9-amino-,9-methoxy, and 9 : 10-dibenzyl derivatives, and phenanthra-ace-naphthene (11). The production of mesoblastic tumours in ratsand mice following the intraperitoneal injection of 1 : 2 : 5 : 6-dibenzanthracene in a fatty medium has been described by H.Burrows.41 The hydrocarbon was dissolved in lard in a concen-tration of O.lyo, and the tumours conformed to the usually acceptedcriteria of malignancy.More active even than 1 : 2 : 5 : 6-dibenzanthracene is 5 : 6-cyclo-penteno-1 : 2-benzanthracene (111), and the carcinogenic activityof 6-isopropyl-1 : 2-benzanthracene (IV) has also been established.Met,astases in the axillary glands and lungs were obtained in fivemice t o which the cyclopenteno-compound was applied.Theevidence so far obtained suggests that a molecular structure cpn-sisting of ring substituents attached to the 1 : 2- and 5 : 6-positionsof the anthracene ring system is particularly efficacious in pro-moting carcinogenic activity.1 : 2-Benzanthracene is itself in-active, and the inactivity of 2’ : 3’-phenanthra-1 : 2-anthracene39 Proc. Roy. SOC., 1932, [El, 111, 485; A., 1156.40 Ann. Reports, 1931, 28, 126. 41 Proc. Roy. SOC., 1932, [B], 111, 238248 BIOCHEMISTRY.(a six-ring compound) and of 4 : 5-benz-10 : 11-(1’ : 2’-naphtha)-chrysene (a seven-ring compound) indicates that the molecularcomplexity must be restricted within fairly narrow limits for themanifest ation of carcinogenic activity.Vitamin A .Up to the present no crystalline preparation of vitamin A, orof a derivative of the vitamin, has been prepared, so that it is stillnot possible to state with certainty that the vitamin has beenobtained in a state of purity.The characteristics of highly activepreparations have been examined by I. M. Heilbron, R. N. Heslop,R. A. Morton, E. T. Webster, J. L. Rea, and J. C. D r ~ m m o n d , ~ ~and, after a comprehensive review of the position, it is concludedthat the most potent preparatioiis obtained by them and by Karrerand his colleag~es,~~ both from mammalian and from fish-liver oils,are qualitatively and quantitatively indistinguishable in respect ofultra-violet absorption. If the products are not homogeneous,then either the non-vitamin material is relatively diactinic, or thepreparations contain substances so closely alike that both exhibitthe 328 mp band. It is pointed out that it would indeed be curiousif exactly the same proportion of material exhibiting negligibleabsorption were present in the products derived from variousspecies of animals.But, on the other hand, the discovery thatthe isomeric a- and @-carotenes may both be transformed in vivointo vitamin A-like substancesu points t o the need for dernon-strating, rather than assuming, strict homogeneity. Heilbron andhis colleagues find their own observations are a t least as consistentwith the formula of Karrer 45 as with any alternative, and regardthe weight of evidence as impressively, though not conclusively,in its favour. It is true that the experimental data on molecularweights46 lead to a va’lue of 320 & 15 as against 286 on the basisof the Karrer formula. This is a small discrepancy, but doubtsconcerning purity are strengthened when the results of a verylarge number of ultimate analyses uniformly indicate values notquite consistent with the C,oH,oO formula.The analysis of hydro-genation products from both crude and distilled vitamin A con-centrates points to the presence of some contaminant in even thepurest preparations. The question is not, however, one of grossimpurity, and it is suggested that there may be present a smallquantity of an alcohol more saturated than vitamin A.4y Biochem. J . , 1932, 26, 1178; A., 1174.43 P. Karrer, R. Morf, and K. Schopp, Ann. Reports, 1931, 28, 221 ; Helv.Chim. Acta, 1931, 14, 1431 ; A., 200.44 Ann. Reports, 1931, 28, 219, 222. 46 Ibid., p. 221. 46 Ibid., p. 221POLLARD AND PRYDE. 249A further communication from Heilbron, Morton, and Webster *'records the extraordinary ease with which vitamin A (concentrate)is transformed into a cyclic derivative in the presence of hydro-chloric acid and alcohol.Dehydrogenation of this product withselenium yielded 1 : 6-dimet'hylnaphthalene. On the basis of theKarrer formula (q.v.) these changes may be formulated as follows :CMe, CH MeI - - - - - - - -Me &H:CHCMe:CH*CH2*OHCyclic product formed from vitamin A. 1 : 6-Dimethylnaphthalene.Similar substituted napht'halenes are obtained from many bicyclicsesquiterpenes by dehydrogenation with sulphur or selenium. Thusthe terpenoid nature of vitamin A is established, and there seemst o be present in the richest concentrates a material which possessesas far as the 14th carbon atom the const,itution advanced by Karrer,Mod, and S ~ h O p p .~ ~Reference was made in the Report of last year to the claim ofH. S. Olcott and D. C. McCann49 regarding the conversion ofcarotene into vitamin A on incubating the hydrocarbon with freshliver tissue in vitro. Further negative results have been recordedby J. L. Rea and J. C. Drumrn~nd,~o and a critical survey, byB. Woolf and T. Moore,51 of the technique upon which the claimwas based leaves little doubt that further proof of the transformationis desirable.An interesting observation regarding the action of antimonytrichloride on carotene has been made by A. E. Gillam, I. M. Heil-bron, R. A. Morton, and J. C. Drumrn0nd.~2 These workers findthat on pouring into water the stable blue solution (A max.583-590 mp) obtained by the interaction of the trichloride and carotene,the organic matter may be recovered free from antimony. Theproperties of the substance recovered agree with those of isocarotene,which is devoid of growth-promoting activity and is derived exclus-ively from the optically inactive @-carotene.= A study of theabsorption spectra of the products of the action of antimony tri-chloride on carotene has led J. R. Edisbury, A. E. Gillam, I. M.4 7 Biochem. J., 1932, 26, 1194; A., 1174.4y Ann. Reports, 1931, 28, 222; A., 97.2. Vitaminforsch., 1932, 1, 177; A., 973.81 Lancet, 1932, 223, 13; A., 1174.52 Biochem. J., 1932, 26, 1174; A., 1174.53 R. Kuhn and E. Lederer, Ber., 1932, 65, [B], 637; A., 782.48 LOC.c i t 250 BIOCHEMISTRY.Heilbron, and R. A. Morton 54 to suggest the partial conversion ofthe vitamin into hydronaphthalene derivatives.Vitamin B,.The identity of the substance, or substances, comprising thecrystalline preparations of vitamin B, still remains in doubt.S. Otake 55 has claimed that his anti-neuritic preparation (oryzanin)from rice bran yields an active hydrochloride, C6H,02N2,HC1,m. p. 250°, resembling Jansen’s crystalline vitamin B,. A. Windausand his collaborators 56 have obtained from yeast a highly activecrystalline anti-neuritic preparation in which they revealed thepresence of sulphur. On the basis of analyses of the crystallinepicrolonate, they tentatively suggested the formula C,,H,,ON,S forthe vitamin. The earlier work of A.G. van Veen 57 led him to sug-gest a formula very similar to that of Otake, namely, C,H,,O,N,,HCI,but further investigation 58 has confirmed the presence of sulphur,and van Veen now suggests as the most probable formula for thehydrochloride, C1,H2,0,N,S,2HC1. The preparation agrees inmelting point, chemical properties, and anti-neuritic activity withthat of Windaus and his colleagues. The present position hasbeen reviewed by R. Tsche~clie,~~ who concludes that the crystallinehydrochloride obtained from the Windaus preparation is identicalwith that of Jansen and Donath, which likewise contains sulphur.The question of the purity of these preparatlions must still remainopen, however, to judge from an examination of the problem byH. W.Kinnersley, J. R. P. O’Brien, and R. A. Peters.6o Theseworkers find that the crystalline hydrochloride, obtained from yeastby the charcoal adsorption methods of Kinnersley and Peters,61contains sulphur which cannot have been introduced during theisolation procedure. The crystalline hydrochloride has been pre-pared with an activity of 2-4 y per diem (pigeon dose). A similarmethod of test showed the Jansen and Donath crystals from rice tohave an activity of 5-8 7 per diem, and it was suggested that thepreparation obtained by Peters and his colleagues was more potentthan that of Windaus.62 This has now been confirmed by directfi4 Riochem. J., 1932, 26, 1164; A,, 1174.5 5 J . Agric. Chem. Soc. Jupun, 1931, 7, 775; A., 657.56 A.Windaus, R. Tschesche, H. Ruhkopf, F. Laquer, and F. Schultz, 2.6 7 Rec. trav. chim., 1932, 51, 265; A., 433.5 8 A. G. van Veen, Z. physiol. Chern., 1932, 208, 125; A., 782.69 Chem.-Ztg., 1932, 56, 1 6 6 ; A., 547.6o J . Physiol., 1932, 76, 17P.O1 “Chemistry a t the Centenary Meeting of the British Association,”E2 A. Windaus, et ul., loc. cit.physiol. Chem., 1932, 204, 123; A., 310.Heffer and Son, Cambridge, 1932, p. 131POLLARD AND PRYDE. 251test,63 the vitamin B, units 64 per milligram being, for the Windauspreparation 260-280, and for the Peters preparation 470. Thetest used was the curative pigeon method. Moreover, Peters andhis colleagues have found it possible to fractionate their crystallinepreparation still further and they conclude that the Windauspreparation cannot be the pure vitamin B,.Vitamin C.The year under review has seen a considerable extension of thechemical problems arising from the investigation of the anti-scorbutic vitamin.At the present time there seem to exist reason-able grounds for the belief that the vitamin has been isolated in apure crystalline state.First, reference must be made to a series of publications byRygh and his collaborators. Results published early in 1932 by0. Rygh, A. Rygh, and P. Laland 65 made the interesting claimthat ethereal extracts of neutralised orange-juice, possessing a highanti-scorbutic activity, yielded a syrup and crystalline narcotine.The latter is inactive against scurvy, but it was claimed that afterirradiation with ultra-violet light it developed anti-scorbuticproperties.It was suggested that this activity developed as aresult of demethylation of the alkaloid, and it was further claimedthat the o-diphenol resulting from this demethylation (methyl-nornarcotine), obtained by heating narcotine with concentratedhydrochloric acid for eight days a t loo", was highly active in pro-tecting guinea-pigs from scurvy. 66 P. Laland G7 stated that narcotinewas present in unripe tomatoes, cabbages, and potatoes, and theunderlying theory seemed to involve the formation of activedemethylated products during ripening. Further investigation ofthis interesting theory by R. L. Grant, S. Smith, and S. S. Zilva,680. Dalmer and T. Moll,69 W. A. Waugh and C. G.King,70 3. Till-mans and P. HirschY7l E. Ott and K. Pa~kendorff,~2 and J. Briigge-mann 73 has failed to corroborate the original claim. A recentpaper by 0. Rygh and A. Rygh '* seems to imply a modification of63 H. W. Kinnersley, J. R. O'Brien, and R. A. Peters, Nature, 1932, 130,774.64 Medical Research Council, Pharm. J., 1932, 129, 5 ; A,, 886. (12 mg.Jaiisen acid clay = 1 pigeon dose.)Z.physio1. Chem., 1932, 204, 105, 114; A., 310.6 6 See also 0. Rygh, Z. Vituminforsch., 1932, 1, 134; A . , 783; A. W. Owe,6 7 Z.physio1. Chem., 1932, 204, 112; A , , 311.c8 Biochem. J., 1932, 26, 1628; J . SOC. Chern. Ind., 1932, 51, 166.69 2. physiol. Chem., 1932, 209, 211; A., 1069.70 J . Biol. Chem., 1932, 97, 325; A., 973.'i2 2. physiol. Chem., 1932, 210, 94.T'idsskr.Kjemi Berg., 1931, 11, 120; A., 201.71 Biochem. Z . , 1932, 250, 312.74 Ibid., p. 275. 73 Ibid., 211, 231252 BIOCHEMISTRY.the original claim in that it is now suggested that the active sub-stance may be a combination of methylnornarcotine with a uronicacid.A much more general acceptance has been accorded to strikingnew results for which A. Szent-Gyorgyi 75 is responsible. In 1928Szent-Gyorgyi, 76 in studying peroxidase systems, isolated fromthe cortex of the suprarenal glands a crystalline substance, CsHsOc,isomeric with the lactone of glucuronic acid, and apparently belong-ing to the uronic acid group, which he referred to simply as hexuronicacid. The substance possessed strong reducing properties and waspresumed to be, on very good evidence, the same substance as thatresponsible for the reducing power of many plant extracts.Thepure compound has been studied by E. L. Hirst and R. J. W.Reynolds 77 and, on the basis of their results, W. N. Haworth 78ascribed to it the constitution of a 6-carboxylic acid of a keto-hexose. A crystalline monoacetone derivative has been described, 79and further chemical investigations by E. G. Cox, E. L. Hirst, andR. J. W. Reynolds 80 have led them to suggest the following tauto-meric structures :CO,H*CO*C( OH):CH*CH( OH)*CH,*OH SCO,H*CO*CO*CH,*CH( OH)*CH,*OHThe double bond in the enolic modification readily accounts forthe strong reducing properties, similar behaviour having beenobserved in an unsaturated trimethyl derivative of glucurone (thelactone of glucuronic acid), prepared synthetically by J.Prydeand R. T. Williams.81 The hexuronic acid of Szent-Gyorgyi doesnot form a lactone, so that, although it is isomeric with the lactoneof a typical hexuronic acid, strictly speaking it does not belong tothis group of compounds. Szent-Gyorgyi and Haworth havesuggested the name “ascorbic acid” in place of the previouslyused “ hexuronic acid.” 81aHexuronic acid can be oxidised reversibly and irreversibly, andit is to the double function of oxidation and reduction in the re-versible change that the acid probably owes its biological activity.The parallelism between the reducing power and the anti-scorbuticpotency of plant extracts has been investigated in a series of well-documented researches by s.s. Zilva and his collaboratorsYs2 andmore recently by J. Tillmans, P. Hirsch, and J. J a c k i s ~ h . ~ ~ The7 B Nature, 1932, 129, 943; A., 886.77 Nature, 1932, 129, 576; A., 648. Ibid., p . 576; A . , 548.79 L. v. Vargha, ibid., 130, 847. Ibid., p. 888.81u Ibid., p . 24.82 Ann. Reports, 1927, 24, 247; 1928, 25, 270.83 2. Unters. Lebensm., 1932, 68, 241, 267, 216; A., 658.76 Biochem. J., 1928, 22, 1387.Ibid., 1933, 131, 67POLLARD AND PRYDE. 253latter workers claim t'o have shown that the vitamin C content andthe reducing capacity are, under many conditions, strictly parallel.Moreover the reducing substance studied by them may be oxidised,like hexuronic acid, in a reversible and an irreversible manner.Biological feeding experiments by J.L. Svirbely and A. Szent-Gyorgyi 84 show that guinea-pigs have been completely protectedfrom scurvy for a period of ninety days by the administration of1 mg. daily of pure hexuronic acid. This claim has been confirmedby W. A. Waugh and C. G. King S5 (who place the dose at 0.5 mg.per day), by 0. Dalmer and T. M011,8~ by S. S. Z i l ~ a , 8 ~ and byL. J. Harris and J. R. M. Innes.88 The protective amount of thepure acid, 0-5 to 1.0 mg. per day, is approximately that of thereducing substance present in the protective dose of plant extracts(e.g., 1 to 1.5 C.C. of lemon juice). Harris and Innes 8s find that1 mg. of hexuronic acid has an activity slightly greater than thatof 1 C.C. of orange juice, and state that the raw suprarenal cortexhas a high anti-scorbutic activity approximately equal to itshexuronic acid content.Hirst and his associates have examinedthe absorption spectrum of de-citrated lemon juice and have estim-ated that the hexuronic acid content corresponds with the recordedevaluation of the anti-scorbutic activity of the isolated acid.This body of evidence seems to afford reasonably conclusiveproof that Szent-Gyorgyi's hexuronic acid is vitamin C, but onemust reserve a final judgment. In particular one would call atten-tion to the fact that, the identity of hexuronic acid and the vitaminbeing assumed, the protective dose is of a considerably higher orderthan that of the other vitamins as far as these are known.Vitamin D.Full details of the properties of the crystalline preparation ofvitamin D obtained by the German workers have been publishedby A.Windaus, 0. Linsert, A. Luttringhaus, and G. W e i d l i ~ h . ~ ~There is general agreement that the product obtained by them isidentical with the calciferol of F. A. Askew, R. B. Bourdillon, et al.,which was described in the Reports of last year.s2 The Germanworkers have also obtained the pyrocalciferol, first described bythe British workers, together with an additive compound of pyro-calciferol and an isomeric alcohol. The structure of vitamin D84 Biochern. J., 1932, 26, 865; A., 886. See also Nature, 1932, 129, 576,690 ; A., 548, 657.86 LOC. cit. S6 2. physiol. Chmn., 1932, 211, 284; A., 1069.Nature, 1932, 129, 943; A., 887.Lancet, 1932,223, 235; A., 1175.89 LOC. cit.9O E. G. Cox, E. L. Hirst, and R. J. W. Iteynolds, Zoc. cit.9 1 Annakn, 1932, 482, 226; A., 311. 92 Ann. Reports, 1931, 28, 215254 BIOCHEMISTRY.now remains to be elucidated and there is little doubt that withthe help of the Rosenheim-King cholane formula, and the conse-quent advances in our knowledge of the chemistry of the sterols,this problem will soon be materially advanced.With regard to the toxicity of large doses of vitamin DYg3 theview that this is an inherent property of the vitamin and is notdue t,o a contaminant is supported by new results of Sir H. H.Dale, A. Marble, and H. P. Marks.94 It is shown that pure calci-ferol has in dogs the same toxic action, in excessive doses, as thecrude product obtained by irradiating ergosterol.The toxic actionis obtained by intravenous injection as well as by oral administration,and the congestion of the alimentary mucosa, produced by suchfatal doses, is equally pronounced with either method of adminis-tration. Of particular interest, in view of the association of theparathyroid gland with calcium metabolism, is the observationthat complete parathyroidectomy does not prevent, or significantlyhinder, tjhe fatal intoxication produced by large doses of calciferol.At most it lowers the level of concentration reached by the bloodcalcium before death. The results, therefore, do not lend supportto the view that vitamin D in excessive doses acts by promotingsecretion of the parathyroid hormone, or by rendering the organismmore responsive to its action.PLANT BIOCHEMISTRY.Mineral Nutrients and the Growth of the Higher Plants.Meclzanism of Nutrient Intake.-Considerable attention continuesto be given to this important but complicated problem, moreespecially from the viewpoint of the mutual influence of ions onthe rate of their absorption by the plant roots.Individual casesof inter-ionic effects are recorded in considerable number, but thesehave tended to emphasise a multiplicity of factors concerned ratherthan to yield data of a constructive nature. It would appear thatmore definite progress is likely to result from the careful applicationof the electro-physical concepts of the nature of electrolyte solutionsand of membrane diffusion to the problems of plant nutrition.Thus, W.Thomas,95 in a very suggestive discussion of the reciprocalaction of nitrogen, phosphorus, and potassium in plant assimilation,illustrates the manner in which conflicting views of several aspectsof ion absorption may be reconciled. The " selective " absorptionof ions and the influence thereon of the hydrogen-ion concentration93 Ann. Repovts, 1931, 28, 218.94 Proc. Roy. SOC., 1932, [R], 111, 522; A., 1176.95 Soil Sci., 1932, 33, 1 ; B., 276POLLARD AND PRYDE. 255of the nutrient solution find explanation on the basis of the Donnanequilibrium and the physical factors controlling the mobility ofions. Diverse views of the physiological balance of nutrients inrelation to Liebig's " Law of Nnimum " and its corollary may beexpressed as variants of the same basic phenomena.In a some-what analogous attempt to link the nutrient absorption of plantswith fundamental physico-chemical phenomena, H. P. Cooper 96observes the close correlation between the proportions of elementsin the ash of plants and their positions in the electromotive series.Since also there is a qualitative relationship between the order ofremoval of cations from soils by electrodialysis and their absorptionby plants, it would seem that considerations of electrode- andionisation-potentials of the elements concerned may afford a basisof explanation of the mechanism of the nutrient intake of plants.The effect of homologous series of ions on the growth of seedlingshas been examined by K.Pir~chle,~' who shows that growth responseis related to the position of the ion in the series and to the structureof the corresponding atoms. The current tendency to ascribe thecontrol of the absorption of minerals to more purely physicalforces and to minimise the effects of inherent physiological activityor adaptability of the plant is shown in a variety of papers. Thus5. Mucco 98 indicates the potential difference between plant leavesand the soil adjacent to the roots to be a controlling factor inthe ratio of absorption of nutrient ions. Pirschle (Zoc. cit.) andF. C. Steward gg show that temperature and light intensity, whileaffecting physiological activity in general, do not alter, to anymarked extent, the relative order of intake of ions by plant cells.Both writers, too, emphasise the part played by carbon dioxide inmaintaining a suitable hydrogen-ion concentration in the nutrientmedium, thus compensating for the unequal penetration of anionsand cations.Nitrogen Assiwdution and Growth.-Diff erences in the responseof plants to ammonium salts and to nitrates again form the basisof much experimental work.Although under conditions prevailingin normal soils the problem seldom arises, it becomes of considerableinterest in the physiological aspect of internal nitrogen economyand metabolism. In many plants examined, the growth responseto ammonium salts is optimal from nutrients having a neutral orslightly alkaline reaction, whereas nitrates are the more effective in96 Soil Sci., 1930, 30, 421; B., 1931, 175; also Proc.2nd. Internat. Cong.97 Jahrb. wiss. Bot., 1930, 72, 335; 1932, 76, 1 ; A., 1931, 174; B., 695.9 8 2. PJlanz. Dung., 1932, 24A, 334; A., 183.99 Protophzsmu, 1932, 15, 29; A,, 664.Soil Sci., 1932, 4, 164256 BIOCHEMISTRY.acid-to-neutral media.l, 293 It is pointed out by V. Tiedgens andW. A. Robbins2 that while ammoniacal nitrogen is absorbed bytomatoes over wide ranges of pH, effective utilisation and elabor-ation into more complex bodies does not occur unless the mediahave pa >7*0. It is possible that the accumulation of ammoniawithin the plant may become toxic in cases where the physiologicaldetoxicating capacity of the plant (W. Ruhland and K. Wetzel*)is exceeded.The injurious effect is attributed by A. B. Beaumontand his colleagues to a disturbance of normal metabolic processes.This view receives some support from observations of the alteredintake of other nutrients occurring when nitrogen is supplied as anammonium salt. ascribes the failure of kugar-cane plants grown with ammonium sulphate to a deficiency ofadsorbed calcium. I n experiments with cotton K. T. Holley,T. A. Pickett, and T. G. Dulin show that the use of ammoniacalnitrogen in culture solutions leads to a much reduced intake ofbases, especially calcium and magnesium.Differences in growth response and composition of plants sup-plied with ammonium salts or with nitrate are recorded by R. M.Addoms and F. C. Mounce * in the case of cranberries.Ammoniumsalts produced much greater runner growth than did nitrates, lowconcentrations of which stimulated, and higher concentrationsrestricted, vegetative growth. Where urea was supplied to sugar-cane plants there was a characteristic increase in the number ofsuckers produced (Purdo, Zoc. cit.).That nitrogen may be assimilated from more complex substancesis shown by Beaumont (Zoc. cit.) in the case of tobacco, which canutilise urea, asparagine, and cystine but not arginine, alanine,glycine, leucine, acetamide, or cyanamide. A. I. Virtanen recordsthat aspartic acid is utilisable by legumes but not by cereals.Potassium and the Growth and Composition of Plants.-The associ-ation of potassium in plants with respiratory activity and carbo-hydrate synthesis is of long standing, but in many instances attemptsto elucidate definite numerical relationships have led to contra-dictory results.The gradual acceptance of the idea of “luxuryconsumption,” i.e., the intake of nutrients in amounts in excess ofThus 5. H. PurdoAnn. Reports, 1931, 28, 241.R. M. Addoms and F. C . Mounce, Plant PhysioZ., 1932, 7, 643.Ann. Reports, 1930, 27, 245.J . Agric. Res., 1931, 43, 559; A., 1932, 101.4th Gong. Internat. SOC. Sugar Cane Tech., 1932, Bull. 13; B., 1932, 1047.Georgia Agric. Exp. Sta. Bull., 1931, No. 169.Plant PhysioZ., 1931, 6, 653; B., 1932, 201.S u o m n Kern., 1932, 5, 67; A., 975.a New Jersey Agric. Exp. Sta. Bull., 1931, No. 536; B., 1932, 567POLLARD AND PRYDE.257physiological requirement, has brought to light one source ofmisunderstanding in the potassium-carbohydrate relationships.This phenomenon, effectively demonstrated by F. Sekera lo in 1928and by other investigators since that time, would appear t o beparticularly marked in the case of potassium. Thus A. E. V.Richardson, H. C. Trumble, and R. E. Shapter l1 observe thatduring the migration of mineral substances from the leaves ofgrasses during maturation, nitrogen and phosphorus accumulate instem bases and roots, but about one quarter of the total potashintake actually returns t o the soil. This is possibly related to thefact that a very large proportion of the total potash content ofplants remains in a soluble condition (G. Janssen and R.P. Bar-tholomew 12) and as a result of rapid translocation, full physiologicalactivity may be maintained by a minimum proportion of potassium.F. J. Richards l3 adds further evidence of the solubility of plantpotash by indicating the probable leaching by rain of potash fromleaves rich in that element but not from those of potash-deficientplants.The function of potassium within the plant is not limited to itseffect on carbohydrate metabolism. Relationships between potass-ium and nitrogen metabolism are indicated not only by the growthresponse of plants to suitably balanced nutrients, but also byexamination of the nitrogen distribution of plants with regulatedpotash supply. This aspect of potash nutrition is discussed byJanssen and Bartholomew (loc.cit.), Richards (Zoc. c i t . ) , and byG. Gassner and G. Goeze.l*The action of potassiuni in increasing the stiffness of cerealstraws is examined by W. Acker,15 who shows by physicalmeasurements that the stability of barley straws increases with thepotash supply t o a maximum value corresponding to a definiteN : P : K ratio. This maximum differs from that associated withthe maximum crop yield. That definite modifications in the struc-ture of the mechanical tissues (especially of the nodes) can beascribed t o variations in potash nutrition is shown by C. Blattnyand V. Vukolov.16Boron and Plant Growth.-Evidence of the necessity of thiselement for the growth of plants continues to be forthcoming.lo 2. Pflanz. Dung., 1928, 7B, 633; B., 1929, 67.l1 J.Counc. Sci. Ind. Res. Australiw, Bull. 66 (1932) ; B., 1096.l2 J. Agric. Res., 1930, 40, 243; B., 1930, 387; also J . Amer. SOC. Agron.,l3 Ann. Bot., 1932, 46, 367; A., 660.lo Ber. &ut. bot. Ges. (Pestschr.), 1932, 50A, 412; A., 890.l5 PfEanzenbau, 1932, 9, 104; B., 1096.16 Erkhr. PJlanze, 1931, 27, 355; A., 1932, 204.1932, 24, 667.REP.-VOL. XXIX. 258 BIOCHEMISTRY.J. S. MacHargue and R. K. Calfeel’ show that in lettuce borondeficiency results in a type of leaf-burn and later in the death oftissues a t the growing point. I n plant metabolism boron cannotbe replaced by any other element. Borax, but not boric acid,stimulates the growth of wheat l8 and of clover,lg red cloverappearing to be more sensitive than the grasses in this respect.Boron injury to wheat occurs in nutrient solutions containingmore than 5 p.p.m.of this element,20 but F. M. Eaton21 recordsthat cotton plants do not produce maximum growth in nutrientscontaining less than the surprisingly high concentration of 10 p.p.m.Boron accumulation is most marked in leaves. Citrus leavesnormally contain 100 p.p.m. of boron, but in trees injured byirrigation with water containing boron this value was increased tomore than 1000 p.p.m.22Calcium and Plant Growth.-The relatively few papers to beconsidered under this heading are concerned with the confirmationor elaboration of existing data rather than with the introduction ofnew subject matter. Calcium deficiency in tomatoes results in achlorosis beginning in the upper stems and leaves, and, in additiont o the characteristic decay of root tips, there is a sloughing of cellsin the upper portions of the root.This is ascribed to the incom-plete development of calcium pectate in the middle lamella.Deficient plants fail to assimilate nitrate and accumulate carbo-hydrates, although sugar translocation and starch digestion appearto be undisturbed. Granular proteinaceous inclusions also appear.The calcium in deficient plants is almost entirely insoluble and itsrate of utilisation so small that normal cellular structure in thetissues cannot be n~aintained.~~ In an examination of calcium-deficient apple trees M. B. Davis a4 records increased shoot growthand production of enlarged leaves in the early stages of deficiency,followed by tissue breakdown later.The total ash content of suchtrees is abnormally low and contains a relatively high percentage ofpotassium and magnesium but low proportions of calcium andphosphorus. W. A. Albrecht and H. Jenny25 show that calciumdeficiency is an important factor in the appearance of “damping1’ Plant Physiol., 1932, 7, 161 ; B., 441.18 H. S. Morris, Bull. Torrey Rot. Club, 1931, 58, 1; A., 1938, 664.l9 R. E. Guilbert and F. R. Pember, Plant Physiol., 1931, 6, 727; B., 1932,Zo H. S. Morris, Zoc. c i t .22 C. S. Scofield aid L. V. Wilcos, U S . Dept. Agric. Tech. Bull., 1931, No.23 G. T. Nightingale, cl al., f’1a)j.l f’hysiol., 1931, 6, 605; A . , 1932, 205.24 J . Pomology, 1930, 8, 316; d., 1931, 273.2G Bot.Gaz., 1931, 92, 263; U., 1932, 200.200.31 Soil Sci., 1932, 34, 301; B., 1129.264; B., 1932, 317POLLARD AND PRYDE. 259off ” o€ soya bean seedlings, and at all ranges between pH 3.8 and6-9 an increased calcium supply in the nutrient reduces the numberof diseased plants. In this respect calcium is a much more activeagent than magnesium or potassium.Intake and Distribution of Mineral Substances during &ow.&-Among a number of investigations on this subject reference shouldbe made to the work of H. Wagner on oats 26 and sugar beet.Z7 Inoats the general decline in the percentage of nitrogen, phosphate,and potassium with growth is temporarily interrupted at the periodof shoot production and again at the blossoming stage.The totalcontent of the nutrients in the stems and leaves reaches a maximumprior to the period of active seed formation and is followed by amovement of nitrogen and phosphorus from stems and leaves andof potassium from leaves only, into the maturing seed. In generalthe .maximum intake of nutrients by stems and leaves precedesthat of organic matter production, but in flowers and seeds the twomaxima are practically simultaneous. In the case of sugar beetthe general decline in percentage nutrient contents of leaves withgrowth was limited largely to nitrogen until the period of rapidsugar accumulation ; the percentage of potassium then decreasedsomewhat and that of calcium considerably. The percentage ofphosphorus did not change appreciably throughout the first yearof growth.The rates of nutrient intake and organic matter pro-duction in the first-year leaves were closely parallel, but in thesecond-year leaves mineral intake preceded the formation of organicmatter. In this respect and also in the translocation of mineralsfrom leaves to seeds the second-year growth of beet resembled thatof oats. Along analogous lines the assimilation and translocationof minerals in the wheat plant are examined by F. Knowles and5. E. Watkin.28 The total intake of nutrients by wheat plantsincreased steadily until after the emergence of the ears. Thesubsequent intake declined in rapidity and the individual elementsattained their maximum values at varying periods prior to harvest-ing, uix., potassium, 7 weeks ; calcium, chlorine, 5 weeks ; nitrogen,3 weeks ; carbon, phosphorus, silica, 2 weeks.The translocationof nutrients from stems to grain ceased one week before harvesting.Indications of a downward movement of potassium, calcium, andchlorine with approaching maturity are recorded. The nitrogencontent of the organic matter of the ear decreased as maturityapproached. An investigation of the soya bean by H. L. Borstand L. E. Thatcher 29 reveals a genera1 similarity in the nutrient2 6 Z. P’anx. Dung., 1932, %A, 48; B., 696.28 J . Agric. Sci., 1931, 21, 612; B., 1932, 38.39 Ohio Agric. Exp. Sta. Bull., 1931, No. 494; A,, 1932, 436.2 7 Ibid., p. 129; B., 811260 BIOCHEMISTRY.intake but with certain characteristic divergences.Thus thegeneral decrease in the percentage of nutrients in the plants withadvancing age is interrupted, in the case of nitrogen by a period ofincrease toward maturity. The mature seed contained more thanone half of the plant’s total nitrogen, a great proportion of potassiumand a smaller proportion of calcium than any other organ of theplant.Plant Saps.-Continued interest in this subject is manifestduring the period under review. Variations in composition resultingfrom diverse methods of extraction have been clarified to someextent by further work of J. D. Sayre and V. H. Morris.30 I nsuccessive fractions of sap obtained from maize by increasingpressure the definitely soluble materials, total- and reducing-sugars, nitrate, and inorganic phosphate remain constant.Otherconstituents which may be presumed to occur, a t least partially, ina colloidal condition, e.g., total solids, total nitrogcn, and phos-phorus, tend to decrease as the pressure rises. It is concluded thatin so far as the constituents in true solution are concerned the sapcomposition is representative of that of the whole plant. The re-action of saps has been examined by K. Biining and E. Boning-SeubertY3l who show that in tobacco the nature of the nutrient doesnot markedly affect the pH of leaf juices but does produce a consider-able effect on the buffer capacity. Correlation between buffer indexcurves of the sap and the composition of the sap are indicated.Calcium-deficient plants show a rather high pB and low buffercapacity in the sap, and vice versa.Deficiency of potassium andphosphate produces a highly buffered sap, and an excess of acidicions in the nutrient a poorly buffered sap. Iron distribution inplants and the p , of the sap appear to be closely related,32 high pHbeing associated with low soluble- and high total-iron contents, aidlow p, with high soluble- and low total-iron contents. The sensi-tiveness of the condition of iron and presumably of its physiologicalfunctions in plants to changes in light intensity is revealed by theobservation that diurnal changes in the pII of the sap due to lightchanges are reflected in variations of the proportion of soluble iron.Translocation of iron occurs principally in the xylem and precipit-ation, which takes place over a wider p,-range than in purelyinorganic systems, is most marked in tissues of high pa lying adjacentto others of low pH.I n plants whose tissues have a low and fairlyuniform pR, precipitation of iron is small and the element remainsevenly distributed throughout all tissues. The parallelism between30 Plant Physiol., 1932, 7, 261; A., 1180.33. Biochem. Z., 1932, 247, 35; A., 786.32 C, H. Rogers and J. W. Shive, Plant Physiol., 1932,7, 227; A., 1181POLLARD AND PRYDE. 261high iron contents and high acidity in pear sap is also recorded byJ. Oserk~wsky,~~ who observes that these conditions are mastmarked in the early part of the growing season, but the period ofhigh acidity is prolonged after the seasonal decrease in iron contentcommences.It is also significant that among trees of the sameorchard there is no appreciable difference in the pH or iron contentof the sap of normal and chlorotic branches. In an examination ofsap from mulberry leaves, Y. Imamura and M. Furuya34 indicatethe nature of the gradient in sap concentration in various celllayers, vix., upper epidermis > lower epidermis > spongy paren-chyma > palisade tissue. The sap concentration generally, increaseswith the age of the leaves up to maturity and subsequently declines.Changes in the sugar content of saps corresponding with alterationsin physiological activity are recorded by a number of workers.R. C. Cole 35 records greater proportions of glucose than of sucrosein stems and leaves of potato plants.Regular diurnal changes tookplace in the glucose concentration, but the sucrose content remainedat approximately the same level throughout the day. The totalsugar content increased with growth, but was not directly affectedby the manurial treatment of the soil. Fertiliser applications,however, definitely influence the mineral constituents of sap, therebeing a general tendency to associate higher sap concentrations withhigher proportions of the respective ions in the soil. A somewhatunexpected instance is, however, recorded by N. A. Pettinger,36working with maize. Pertilisers containing chloride increased thechloride concentration of the sap to a considerable extent, the effectbeing persistent for a long period of time.Sulphate-containingferfilisers, however, caused little, if any, change in the proportion ofsulphate in the sap. An association between the crop-producingpower of vines and the sap concentration of carbohydrate andasparagine a t the period when buds are breaking is shown to existby L. Moreau and E. Vinet,37 and the relationship is confirmed bythe fruit yield increase, following artificial injection of glucose intothe stems immediately prior to the budding period.Changes in, and Distribution of Certain Plant Constituents.Climate and the Nature of Plant Substances.-Reference shouldbe made here to a series of papers by J. B. McNair 3* in which are33 C. H. Rogers and J. W. Shive, Plant Physiol., 1932,7, 253; A., 1180.34 Bull. Sericult. Silk I n d .Japan, 1932, 4, 7; A., 977.35 Soil Sci., 1932, 33, 347 ; B., 697.36 J . Agric. Res., 1932, 44, 919; A., 1181.37 C m p t . rend. Acad. Agric. France, 1932, 18, 193 ; B., 362.38 Amr. J. Bot., 1931,18,416; 1932,19, 168, 255, 518; A., 99, 663, 665;also Science, 1932, 76, 8 3 ; A., 1177262 BIOCHEMISTRY.traced relationships between the chemical composition and, in somecases, physical properties of the principal plant constituents, and theenvironmental conditions of growth. Thus the acid-, alcoholic-,ester-, and hydrocarbon-constituents of volatile oils, saponins, andcarbohydrates from plants occurring in temperate regions have, ingeneral, higher molecular weights than those from tropical plants.Dextrorotatory compounds are more general in the volatile oils oftemperate-region plants, and laevorotatory in tropical plants.Amongsaponins, those of tropical areas are the less toxic. Acetone is morecommon among the products of hydrolysis of cyanogenetic glucosidesof temperate zones, and benzaldehyde among those of tropical plants.Nearly all plants containing cyanogenetic glucosides also containcalcium oxalate depositions, but in temperate plants the trihydratedand in tropical plants the monohydrated crystals predominate.Temperate-plant starches are the more reactive and have widerranges of polarisation values and lower gelatinisation temperaturesand are less " saturated " towards iodine than tropical starches.Essential oils, resins, and calcium oxalate crystals are far morecommonly found in tropical than in temperate plants.The essentialoils and resins occur in most cases in similar anatomic structures andthere is a general tendency for resins to be formed by the condensationor polymerisation of the constituents of the essential oils.Similar relationships are traced among plant waxes and alkaloids,although these are perhaps a little less clearly defined.It is further recorded by S. Ivanov 39 that plant fats from northernareas always contain a larger proportion of unsaturated glyceridesthan those from southern areas, except among those containing oleicacid, in which a climatic influence is not appreciable. Other generalrelationships of a similar nature are shown by the work of N. N.Ivano~.*~Nitrogenous Constituents. -Among investigations of factors in -fluencing the transformation of nitrogen compounds in plantsinterest attaches to that of S.H. E ~ k e r s o n , ~ ~ who traces the effectsof nutrient deficiencies on the reduction of nitrates. Reducaseactivity, while largely influenced by light conditions, practicallyceased in plants deficient in potassium or phosphate. Calcium orsulphate deficiency produced a similar effect but much more slowly.In the case of sulphate deficiency there is a tendency for the main-tenance of a minimum rate of reduction over a period of some weeks.39 Chem. Rund. Mitteleuropa Balkan, 1930, 7, 115; A., 1931, 535; alsoN. N. Ivanov, M. N. Lavrova, and M. P. Gepochko, Bull. appl. Bot. Russia,1931, 25, 1 ; A., 1932, 663.40 Biochem. Z., 1932, 250, 430; A., 1181.dl Contr.Boyce Thompson Inst., 1932, 4, 119; A., 890POLLARD AND PRYDE. 263Regulation of protein metabolism is examined by K. mot he^,*^ whohas isolated from the onion an active substance which under reducingconditions stimulates protease activity and under oxidising condi-tions inhibits it. The material is rich in amino-acid constituents,when reduced responds to the nitroprusside test for the thiolgroup, and is probably glutathione or a closely related substance.T. Schulze43 also records the isolation by a similar process of acystine-like substance which influences proteolytic activity in leavesin a similar manner to the above. The view is also expressed thatthe protein balance in leaves is such as to maintain a characteristic'' stability value " of protein per unit dry weight or per unit surfacearea of leaf.Hydrocyanic acid from cyanogenetic glucosidesactivates protein exchange. Following up earlier investigation^,^^G. Klein and his colleagues 45 have examined the distribution of ureain plants. I n the higher plants a large proportion of urea exists inthe form of ureides (probably of aldehydes), but in many fungi freeurea predominates. In the former urea appears to result from thedestruction of arginine by enzymes. The same author, applyinghis recently developed methods of analysis, examines the distributionof choline in plants, especially in seedlings.46 The choline contentsof fresh seeds is small, leguminous seeds containing more than others.During the germination of maize lecithin- and free-choline (especiallythe latter) increase considerably, the preponderance of lecithin-choline appearing in the cotyledons. Etiolated seedlings have morefree choline and less lecithin-choline than normal.Nitrogen ex-change in seedlings is also examined by P. M c K ~ ~ , ~ ' who observes aclose relationship between the disappearance of insoluble- andprotein-nitrogen during germination of lupin seeds and the increasedproportion of asparagine. Later, as the seedling becomes estab-lished, protein synthesis begins and there occurs a decline in theamount of asparagine and a corresponding increase in proteose.The simpler forms of nitrogen, nitrate, ammonia, amides, and amino-acids appear immediately growth begins and after maintaining amaximum value for a few days decline to a low maintenance level.In germinating soya beans 48 the initial protein decomposition resultsin the production of ammonia and urea.Subsequent changes in the42 Naturwist?., 1932, 20, 103; A., 436.43 Planta [Z. wiss. Biol.], 1932, 16, 116; A., 549.43 Jahrb. wiss. Bot., 1930, 73, 174; A., 1931, 990.4b Ibid., 1931, 74, 429; A., 1932, 313; Biochem. Z., 1931, 241, 413; 1932251, 10; A., 1932, 101, 313, 1179.4 6 G. Klein and H. Linser, Biochem. Z., 1932, 250, 220; A., 1179.4 7 Biochem. J., 1931, 25, 2181; A., 1932, 202.46 W. S . Tao and S . Komatsu, Mem. Coll. Sci. Kyoto, 1931, 14, 287, 293 ;A., 1932, 202264 BIOCHEMISTRY.seedling are due to the action of proteases on glycinin.The ureaseactivity of seedlings is greater than that of the seeds.Seasonal variations in the nitrogen distribution in fruit trees haveagain received attention. A. S. Mulay 49 continues his examinationof Bartlett pear shoots. 50 Among the non-protein nitrogenous con-stituents of current-year shoots, amides and amino-acids in bothwood and bark reach a maximum prior to the commencement ofnew growth. During growth the amide-nitrogen of the wood exceedsthe amino-nitrogen. Basic-nitrogen is low a t mid-summer, butsubsequently rises to attain a maximum some time before newgrowth begins. The insoluble-nitrogen of bark and wood is alsoexamined. In the bark small increases in amide- and humin-nitrogen a t the expense of basic- and residual-nitrogen occur in theearly growing season and later there is a decrease in amino-nitrogenand a corresponding rise in residual-nitrogen as growth proceeds.The principal changes in the wood are shown in a considerable declinein amino-nitrogen and an increase in melanin.Residual nitrogenincreases somewhat after the actual cessation of growth. Similarthough perhaps rather less detailed examinations of apple trees arerecorded by J. T. Sullivan and €1. It. Kraybill 51 and by A. E.Murneek and J. C. Logan.j2 The nitrogen and carbohydrate meta-bolism of celery plants is examined by H. P l a t e n i ~ s . ~ ~ Duringgrowth there is an inverse relationship between the nitrate- andthe amino-nitrogen contents and between the amino- and protein-nitrogen.The proportion of ammonia in the plants was consistentlysmall. Temperature changes had little effect on the rate of amino-acid synthesis. I%elationships between metabolic changes and thcpremature seeding of celery are discussed.Carbohydrates in Plants.-Apart from papers dealing with purelysystematic chemistry, a relatively small number of investigationsfall to be reported here. H. Belval 53a discusses the process of sugarformation in leaves and from a consideration of the wheat plantindicates that in leaves sucrose formation precedes that of the simplehexoses. Sucrose is alsothe first recognisable sugar formed in the banana leaf. Wheat stemsdiffer from those of maize and rice by the presence, along withglucose and fructose, of an alcohol-soluble non-reducing lzevorotatorysugar other than sucrose.Prom the roots of Lycoris squamigeraA fructoside is also formed from sucrose.49 Plant Physiol., 1932, 7, 107, 323; A., 436, 1180.5O Ann. Reports, 1931, 28, 251.61 PTOC. Amer. SOC. Hort. Sci., 1931, 2’7, 220; A., 1932, 99.62 Missouri Agric. Exp. Sta. Res. Bull., 1932, No. 171.53 Cornell Un$v. Agric. Exp. Sta. Mem., 1932, No. 140; A., 1295.5% Bull, SOC. d’Encour., 1931, 130, 605; A . , 1932, 100; see also Chinese J .physiol., 1930, 4, 365; A . , 1031, 130POLLARD AND PRYDE. 265Belval has isolated two fructosides, one of which, Zycoroside,(CaH8,,O4J, [a] - 34", is not hydrolysed by invertase and thesecond 54 has [a] - 19" and is slowly hydrolysed by the enzyme.Carbohydrate changes during seed formation in peas show varietaldifferences in the period of formation of s t a ~ h y o s e .~ ~ In one caseappreciable amounts of sucrose with reducing sugars but no stachyosewere present initially. With the development of starch accumulationreducing sugars disappeared, sucrose decreased in amount, andstachyose appeared only in the later stages. In a second variety theformation of stachyose and of starch occurred simultaneously.Significant differences in the carbohydrate exchange of sterile and ofinoculated soya beans are recorded by E. Ruffer.56 I n the earlystages of growth the greater assimilation by inoculated plantsresulted in relatively greater accumulations of sugars and starch,which were subsequently reduced below the level of sterile plants,presumably as a result of utilisation by the nodule organisms.I nthe Carbohydrate metabolism of Crassulucece, J. Wolf 57 shows thatthe carbohydrate consumption is not exactly balanced by the form-ation of malic acid and carbon dioxide. It is considered that highconcentrations of carbon dioxide in the tissues reduce decompositionby inhibiting the first stage of oxidation (oxalacetic acid formation)and also by causing an increased acetaldehyde accumulation,which in turn restricts the decomposition of a-ketonic acids bycarboxylase. 58Carbohydrate and other changes during the ripening and storage offruits. In the development of apples, starch formation commences(in this country) about, mid- June and after reaching a maximum stage(July-August) the starch content declines steadily until the endof October.In apple tissue there exist a hydrolysable poly-saccharide other than starch or pectin and a polyuronide. Bothsubstances yield arabinose on hydrolysis and are classed as hemi-celluloses.59 Hemicelluloses do not act as reserve carbohydrates,but resemble pectin in structure and function. In peaches, G. T.Nightingale, R. M. Addoms, and M. A. Blake 6o show that pectatesare absent from the flesh cells during ripening and are only to befound in the thick-walled cells adjacent to the epidermis. Proto-pectin, although irregularly distributed, occurs in all cell walls and54 Compt. rend., 1931, 193, 891; A., 1938, 802.55 M. Bride1 and C. Bourdouil, ibid., p. 949; A., 1932, 100.5 6 2.Pflanx. Dung., 1932, HA, 129; A., 1180.57 Planta [Z. wiss. Biol.], 1931, 15, 572; A., 312.58 See also K. Wetzel and W. Ruhland, ibid., p. 567; A., 31%.59 E. M. Widdowson, Ann. Bot., 1932, 46, 597; A., 1070.60 New Jersey A.gric. Exp. Sta. Bulls., 494 and 507; A., 1931, 273.1266 BIOCHEMISTRY,is closely associated with cellulose. In the soft ripe stage there is agradual decline in the protopectin content. The ripening of theJapanese medlar is associated with an accumulation of fructose,sucrose, and malic acid in, and the disappearance of maltose,tartaric acid, and amygdalin from, the pericarp. With advancingripening, dextrin, starch, cellulose, hemicellulose, protein- and non-protein-nitrogen decline steadily in amount. Changes of the reversetype occur simultaneously in the seed, where amygdalin, starch,cellulose, and hemicellulose increase in proportion and maltose dis-appeam61 R.Nuccorini 62 in confirmation of earlier work 63 recordsdifferences in the distribution of organic acids in ripe cherries,peaches, and plums according t o the period of ripening. In general,the proportion of malic acid formed during ripening is smaller, andthat of tartaric acid greater, in warmer than in colder seasons.Characteristics of ripening oranges recorded by P. R. v. d. R.Copeman 64 include a steady increase in total solids and sugars anda decrease in the acids of the juice and also a decrease in the propor-tion of cell-wall material in the pulp. The interesting observation isalso made that spraying with lead arsenate induced a definite de-crease in the acid and a slight decrease in the sucrose (but not reduc-ing sugar) content of the juice and also a significant increase in theproportion of cell-wall material in the pulp.The sugar thataccumulates during the colouring period of fruit is considered byE. W. Allen 65 to consist mainly of sucrose in stone fruits, sucrosepZus reducing sugars in apples, and reducing sugars in pears. Duringthe storage of apples there occurs an inversion of sucrose and hydro-lysis of starch, if any is present. Sucrose inversion and sugaroxidation do not always take place a t parallel rates. Differencesin hexose content thus brought about were shown in fructose but notin glucose, which remained in almost constant proportions.Storagealso involves a steady loss of acid and of insoluble matter. Theextent of the above changes varies somewhat with the period ofpicking. Generally speaking, late gathering results in a low rate oftotal-sugar loss, a high rate of sucrose inversion, a higher level ofconcentration a t which sucrose inversion ceases, and wider variationsin the content of reducing sugars.66 Artificial ripentng induced bytreatment with ethylene appears to follow the normal course inrespect of acid and carbohydrate changes in so far as these have61 ,4. L. Kurssanov, Planta LZ. wiss. Biol.], 1932, 15, 752; A., 435.62 Ann. Chim. Appl., 1932, 22, 10; A., 435.63 Ibid., 1930, 20, 302; A., 1930, 1482.84 Trans.Roy. SOC. S. Africa, 1931, 19, 107; A . , 1931, 882.Hilgardia, 1932, 6, 381 ; A . , 973.ea H. K. Archbold, Ann. Bot., 1932, 46, 407; A., 1070POLLARD AND PRYDE. 267been 68y 699 70 although the changes involved varyconsiderably with conditions of treatment, period of picking, andindividual varieties. Treatment with acetylene 71 has similareffects.Ant7tocya;nirns.-Reference must be made here to the valuable workof Mrs. G. M. Robinson and R. Robinson. Detailed considerationof the synthesis of anthocyanin pigments 72 and the examinationof their distribution in a vast number of plants 73 are beyond thescope of this section of the Report. The simplest type of antho-cyanin is represented by chrysanthemin (cyanidin 3-monoglucoside),which forms the basis of consideration for the structure of morecomplex types.Pelargonin, peonin, cyanin, and malvin conformt o a 3 : 5-di-monoside type and are not classed as biosides. Among3-biosides are included mecocyanin, prunicyanin, etc. No evidenceof the existence of 5-monosides. has been obtained.Colour variations, especially among varieties of the same speciesof plants, are not ascribed to variations in the pB of saps but dependupon differences in the nature of " co-pigments," i.e., substancesforming weak addition compounds with the anthocyanin andeffecting a modification of colour. Such additive compounds usuallydissociate at high temperatures or may be separated by partitionbetween solvents. Co-pigmentation appears to be most marked innatural pigments containing anthoxanthins. Commonly occurringco-pigments include tannin, flavone, and flavonol glycosides. Theexistence of tannin complexes is also recorded by A.G~illiermond,~~who indicates the oxyflavonols as precursors of anthocyanins inflowers of Iris germanim. The rate of formation of anthocyaninpigment in plants appears to vary with the growth rate, the photo-synthetic activity, and the accumulation of nutrient substance^.^^In green fruit during chlorophyll assimilation the formation ofanthocyanin is retarded owing to the production of anthocyanidinsfrom the corresponding oxyflavones. In picked unripe fruit,reduction processes prevail and flavone compounds are converted67 W. B. Davis andC. G. Church, J . Agric. Res., 1931, 42, 165; A., 1931,774.E.H. Kohman, l n d . Eng. Chem., 1931, 23, 1112; B., 1932, 79.69 F. W. Allen, Zoc. cit.70 H. S. Wolfe, Bot. Qax., 1931, 92, 337.R. Hartshorn, Plant Physiol., 1931, 6, 467; B., 1931, 992.7' J., 1931, 2665-2742; 1932, 2221, 2293, 2299, 2488; A., 1931, 1423;1932, 1038, 1140; A. Lebn, R. Robinson, et al., Anal. 2%. Quim., 1932, 30,267 ; A., 859.73 Biochem. J . , 1931, 25, 1687; 1932, 26, 167; A., 1932, 101, 1296.'4 Compt. rend., 1931, 192, 1581 ; 193, 112; A., 1931, 1099.7 5 H. Kosaka, J . Dept. Agric. Kyushu, 1931, 3, 29, 99; A., 1931, 660;1032, 101268 BIOCHEMISTBl*.into antho~yanins.~6 I n wheat and rye, but riot in oats or barley,the anthocyanin colour is of sufficient intensity t o be utilised as anindication of quality."Certain Plant Enzymes and their Artijkial Activation.-Theassociation of certain growth characteristics in plants with enzymeactivity has become very general in recent years.Investigations ofcatalase activity are prominent, and in general indicate that thisenzyme is most markedly active a t the end of a period of dormancyor at the initiation of certain definite stages in growth, e.g., duringseed germination, sprouting of tubers, breaking of buds in fruit ant1other t r e e ~ . ~ ~ a Thus M. N. Pope 78 records maximum periods ofactivity in barley during early germination, during development ofcrown roots, and during early jointing.A. Niethammer 79 correlates germinative capacity in seeds withtheir catalase content. Frost resistance in wheat plants appears t obe related to the catalase activity of the leaf and in partiallychlorotic leaves variations in catalase and in chlorophyll contentsare closely parallel.81 This association of functional with enzymicactivity in plants is commonly reported in the case of amylase andother enzymes and much interest centres round this aspect of thcartificial stimulation of growth processes and especially the intcr-ruption of the normal dormant period.Thc obvious horticulturalvalue of such practice has doubtless been an incentive to numerousinvestigators. Probably the most widely examined activator isethylene chlorohydrin. Potato tubers dipped in a 5% solution ofthis substance show a much accelerated sprouting and an increasednumber of sprouting eyes.This effect is greatest in least mature" seed." Subsequent growth, however, is greatest when well-matured tubers are treated.82 The action of the activator decrease::as the period of treatment approaches the end of normal dormancy.Similarly, ethylene chlorohydrin vapour breaks the dormancy ofmaple and chestnut seedlings *3 and of seeds of maples andTreatment with certain sulphur-containing substances, e.g., thio-J. C. Politis, Praktika, 1928, 3, 440; A., 1933, 312.7 7 G. Gassner and TV, Straib, Pjlanzenbau, 1930, 4, 169; R., 1931, 507.S. Manskaja and M. Schilina, Biochem. Z., 1931, 240, 276; A., 1932, 99.J . Agric. Res., 1932, 44, 343; A., 784.R. Newton and W. R. Brown, Canadian J . Res., 1931, 5, 333; A,, 1931,81 H.von Euler, et al., Arkiv Kemi, Min. Geol., 1931, lOB, No. 13; A . ,82 H. 0. Werner, Nebraska Agric. Exp. Sta. Bull., 1931, KO. 67; B., 1932,83 W. C. Bramble, Science, 1932, 75, 193; B., 396.79 2. Pj-lanx. Dung., 1931, 21A, 69; B., 1931, 776.1465.1931, 1102.318.C. G . Deubner, ibid., 1931, 73, 320; E., 1931, 857POLLARD AND PRYDE. 269semicarbazicle, t8hioglycollic mid, methyl disulphide, t hioglpcol,and derivatives of thiocarbamic acid, is shown by L. P. Miller *5 t ohave a like effect on potato tubers. This stimulation of dormantmaterial to active growth is associated in nearly all cases with asimultaneous increase in enzyme activity notably of catalase oramylase or both. Subsequently, numerous investigators havesought to decide whether enzyme activity is caused directly by theactivator, or whether it is the indirect result of the action of theactivator on other material, or whether the enzyme is actually anecessary intermediary between activator and growth response.Workers from the Boyce Thompson Institute have contributed anumber of papers on this point.J. D. Guthrie8& shows that,among a number of activators examined, those inducing successfulsprouting effects on potatoes either contained sulphur, or producedan increased proportion of thiol derivatives in the tuber as a, resultof an increased pR or reducing power in the potato juice. Stimul-ative effects, however, are not closely correlated with changes incntalase or peroxidase activity nor with the pH or reducing power ofthe juices.In a similar examination of gladiolus corms it is shownE6that treatment with ethylene chlorohydrin increases the catalaseand peroxidase activity and the thiol content of the expressed juiceand of aqueous extracts of dried tissue. F. E. Denny 87 observesthat sprouting response, while closely related to the increased amylaseactivity of the potato, is not directly dependent on the activationof the enzyme by ethylene chlorohydrin or thiocyanates. Later,5. D. Guthrie 88 reports the isolation of glutathione from theexpressed juice of tubers treated with ethylene chlorohydrin but notfrom untreated tubers. The presence of glutathione in plant organsduring active vegetative growth is also recorded in an examinationof Obelia by E.J. L ~ n d , ~ ~ who reports maximum accumulations inthe active tips of stems and roots. The distribution of glutathione inthe plant is paralleled by variations in oxygen consumption, carbondioxide production, methylene-blue reduction, and electric potential.L. Binet and J. MagrouW also regard the glutathione content ofplants as a function of rapidity of growth. The direct activation ofisolated amylase by various sulphur compounds is examined byK,. H. Clark, F. L. Fowler, and P. T. Black.s1 Potassium thio-8 5 Contr. Boyce Thompson Inst., 1931, 3, 309; B., 1931, 85s.85a Ibid., p. 499; A., 1932, 201.8 6 J. D. Guthrie, F. E. Denny, and L. P. Miller, ibid., 1932, 4, 131 ; A., 889,8 7 Ibid., p. 53; A., 661.88 J. Amr. Chern. SOC., 1932, 54, 2566; A., 889.89 Protoplasma, 1931, 13, 236; A , , 1932, 98.90 Compt.rend., 1931, 192, 1415; A., 1931, 989.91 Trans. Roy. SOC. Canada, 1931, [iii], 25,111, 09; A . , 1932, 497270 BIOCHEMISTRY,cyanate, thiourea, and also ethylene chlorohydrin stimulate theaction of malt diastase on starch, each activator exhibiting a specificoptimum concentration giving maximum activity. H. Pringsheim,H. Borchardt, and H. Hupferg2 show that glutathione activatesboth yeast and pancreatic amylases. Dithioglycollic acid, however,is without effect. Reduced glutathione resembles cystine in itsactivating action on proteolytic enz~mes,~3 and it would appear thatthe activity of plant [and animal] cells is largely dependent on theS*S =+= S*H equilibrium. Thus, while fairly definite knowledgehas been obtained of the several factors involved in the activationof dormant plant tissue, the exact position of the enzymes as acausal or resultant factor in vegetative stimulation requires stillfurther elucidation.Growth and Metabolism of Moulds.Nutritional Factors.-The alleged parallelism between the pro -duction of mycelial tissue by Aspergillus niger and the supply ofcertain mineral nutrients, together with the utilisation of thisorganism as an indicator of the nutrient value of soils,94 has lead toa number of investigations of the effect of inorganic materials onthe growth of the mould.I n soil analysis the many externalinfluences on growth are stabilised as far as possible by the use ofmedia containing 1% citric acid and any calcium carbonate in thesoil is previously neutralised with citric acid.Extensive changesin the px of the nutrient are thus prevented. The proportion ofsoluble calcium in the nutrient nevertheless influences the growthof the organism 95 irrespective of the supply of potassium, andhighly calcareous soils yield excessively high values for availablepotassium. Mycelium of A . niger, grown under conditions whichmake the supply of potassium a limiting factor, contains 0.120/,(dry weight) of K,O and production is closely proportional to theamount of this element a~ailable.9~ Correlation between mycelialgrowth and the phosphate supply is less close. This observationmay be related, however, to the fact that A. niger is able to utilise,in addition to alkali and soluble calcium phosphates, the insolublephosphates of iron andof calcium and also the phosphorus of ~ h y t i n .~ '92 Biochem. Z., 1932, 250, 109; A., 1063; also Naturwiss., 1932, 20, 64;A., 304.93 W. Grassmann, et al., Z. physiol. Chem., 1931, 194, 124; A . , 1931, 393.94 H. Niklas, H. Poschenrieder, and J. Trischler, Z. Pflanz. Diing., 1930,g5 H. Niklas, G. Vilsmeyer, and H. Poschenrieder, ibid., 1932, 24A, 167;9 G J . Trischler, Wiss. Arch. Landw., 1931, 7, 39; B., 1932, 617.9 7 T. Simakova aid C . Bovschik, Z . Pflanz. Diing., 1932, 24A, 341; B.,18A, 129; B., 1931, 37.B., 566.74327 I POLLARD AND PRYDE.That mycelium production is also directly related to the mag-nesium supply is indicated recently.g8 The effect of heavy-metalsalts on the growth of fungi, with its obvious bearing on industrialfermentation industries, has again been the subject of considerableinvestigation.J, Talts 99 has examined the acidity produced inmedia by the growth of P. gluucum and distinguishes two phases,v k . , an initial stage characterised by rapid tissue production and amarked increase in hydrogen-ion concentration, followed by asecond stage in which the growth rate is smaller and aciditydiminishes. Salts of zinc, cobalt, nickel, and cadmium in 0.005M-solutions markedly affect the pDH changes in the medium and aretoxic in the order Ni<Zn<Co<Cd. Toxicity is ascribed to aretardation of absorption of nufrients rather t,han to coagulation ofthe colloids of the plasma, and is associated with reduced sporegermination.The effect c,f zinc sulphate on the growth of A . nigeris also examined by K. H . Stehle.9ga Stimulation by small con-centrations of zinc occurs only when the sugar in the nutrient isabove a definite proportion and does not appear if sta,rch or inulinis supplied instead of sugar. The addition of a colloid (agar-agar)prevents the stimulative action of small concentrations of zinc andprotects the fungus from the toxic effect,s of larger ones. Accordingto R. A. Steinberg zinc is to be regarded as an essential nutrientfor AspergiZEus rather than as a stimulant. The apparently irregularaction of iron in the culture of fungi is emphasised and discussedby A. Quilico and A.Di Capua,2 who record the isolation of twostrains of A . niger, one of which gave hardly any citric acid in thepresence of traces of iron, and a second which produced citric acidin proportion to the amount of ferric chloride supplied. Thepresence of cellulosic material also influences the growth of thisorganism, additions to the medium of filter paper, washed peat,powdered barley roots, etc., markedly increasing the amount ofmycelium pr~duced.~Metabolism and Acid Production.-Gaseous exchange in A . oryxceis examined by H. T a m i ~ a , ~ who records the view that the respir-atory quotient is greater or less than the combustion quotient ofthe substrate according to whether the latter is greater or less than98 H. Niklas, H. Poschenrieder, and A.Frey, ErmGr. Pflanie, 1931, 27,99 Protoplasma, 1932, 15, 188; A., 968.99a Bull. Torrey Eot. Club, 1932, 59, 191 ; A., 11GS.1 Zentr. Bakt. Par., 1932, 11, 86, 139; A . , 1168.2 Giorn. Chim. i n d . appl., 1932, 14, 289; A., 968.3 L. E. Kiessling, %. Pjlanz. Diing., 1931, 21A, 86; B., 1931, 774;4 Acta Phytochint., 1932, 6, 227, 265; A., 1167.465; B., 1932, 276.Pjanzenbau, 1932,9,293; A., 1259272 RIOCHENlTSTRY .0.1375 (the combustion quotient of t’he mould constituents taken asa whole). Energy resulting from respiration during vital synthesisappears to be utilised for the maintenance of enzymic and struc-tural energy, balancing heat exchanges in various stages of synthesis,and for activation of the substrate for the acceleration of syntheticreactions.Following up earlier work, the same author records themanner of utilisation of a large number of organic substances forgrowth and/or respiratory purposes, and associates certain specificatomic groupings with their utilisation by the mould.5 It wouldappear that the presence of more than one specific grouping isnecessary for growth. Typical “ chief radicals ” include the groups*CHMe(OH), :CH*C(OM):, and -CH(OH)*CH,*. These must bejoined a t least once with a “ residual radical ” such as will preventp-degradation and fission of the “chief radical.” Fission of di-and poly-saccharides and of glucosidcs precedes their utilisation.The utilisation, as sole source of carbon, of the higher paraffins bya strain of A . versicolor is recorded by S.J. Hopkins and A. C.Chibnall.G Both odd- and cvcn-paraffins up to C,,H,, are attacked,and also higher ketones hut not secondary alcohols. Contrary to theview of W. 0. T a u s s ~ n , ~ the first products of the action on paraffinsappear to be ketones, which gives rise subsequently to shortcr-chain fatty acids. I<. Rernhauer and his colleagues,s in a con-tinuation of their investigations of the various acids produced byA . niger, show that glycollic acid produced from acetates is rapidlyreplaced in cultures by glyoxylic acid as the action proceeds. Bothacids may be converted into oxalic acid. Quantitative examinationof the process in comparison with the conversion of succinates intooxalic acid leads to the view that acetic acid is transformed intooxalic acid by way of succinic rather than through glycollic acid.I n the conversion of ethyl alcohol into citric acid by A .niger thesimultaneous production of oxalic, malic, and tartaric acids is alsore~orded.~ The yield of citric acid is greater and that of oxalicacid smaller than the corresponding amounts formed from acetates.According to T. Chrzaszcz, D. Tiukov, and M. Zakomorny lo the con-version of alcohol into citric acid by PeniciZZium takes place throughthe stages, alcohol + acetic -+ glycollic + Z-malic -+citric acids. The extent of the side reaction, glycollic --+ oxalicacid, varies with the strain of organism used and with the natureof the substrate. In another paper dealing with this point T.Acta Phytochim. 1032, 6, 129; A., 651.Biochem. J., 1932, 26, 133; A., 653.Biochem. Z., 1928, 193, 85; A., 1928, 447.K. Bernhauer and Z. Scheuer, ibid., 1932,253,ll; A., 1168.‘3 K. Bemhauer and N. Bockl, ibid., p. 25; A., 1168.lo lbid., 250, 254; A., 1065POLLARD AND PRYDE. 273Chrzaszcz and D. Tiukov l1 show that for maximum accumulationof citric acid there is an optimum concentration of nitrogen in themedium which depends on the form of the nitrogen. For inorganicforms of nitrogen the optimum is lower than for organic forms.Further, some moulds produce citric acid by deamination withoutthe production of oxalic acid. Considerable yields of acetaldehydeproduced from sucrose by A . niger in media containing sodiumsulphite are recorded by K. Bernhauer and H. Thelen.12 It issignificant that neither citric nor oxalic acid is formed under theseconditions, but both are produced in the absence of sodium sulphite.The formation of itaconic acid by a new organism, A . itaconicus,grown on a sucrose-potassium nitrate medium is of interest. Thechange probably occurs in the order, sugar --+ gluconic acid +citric acid --+ aconitic acid + itaconic acid. The same organism,grown on sucrose-ammonium nitrate, produces 1-mannitol. Fruct-ose (but not glucose) undergoes similar changes.l3Among benzene derivatives obtained by the action of moulds onglucose must be mentioned puberulic acid, C8H606, m. p. 316"(decomp.), probably a dihydroxybenzenedicarboxylic acid, and anacid, C8H406, m. p. 296" (decomp.), not characterised. The acidsare produced by Penicillium puberulum, Bainier, and P. aurantio-virens, Biourge, when supplied with glucose as the sole source oicarbon.14 The course of the degradation, quinic acid --+ proto-catechuic acid -+ pyrocatechol -+ oxalic acid by A . niger isexamined by K. Bernhauer and H. H. Waelsch,15 who demonstratethe disappearance of pyrocatechol on the 6th day of the culture,but the appearance of oxalic acid is not shown until the 9--10thday. Oxalic acid is similarly produced from inositol, gallic, andsalicylic acids. Oxalic acid appears to be the only acid producedby A . niger from potassium salts of d-glycuronic, a-d-galacturonic,and tetragalacturonic acids.16 An extensive survey of the pro-duction of a number of organic acids by modern fermentationprocesses is given by 0. E. May and H. T. Herrick.17 The utilis-ation of olive oii by A . fravus and P. sylvaticzcm is reported byR. S. Katznelson l8 and of linseed and walnut oils by H. Oeffner.19In the latter instances evidence of the formation of y- andl1 K. Bernhauer and S. Biickl, Bioclmn. Z., 1931, 242, 137; +4., 1932, 93.l2 Ibid., 1932, 253, 30; A., 1168.l3 I<. Kinoshita, Acta Phytockim., 1931, 5, 271 ; A., 1932, 93.lC J. H. Birkinshaw and H. Raistrick, Biochem. J., 1932, 26, 441 ; rl., 651.Biochem. Z., 1932, 249, 223; A., 882.E. Hoffman, ibid., 1931, 243, 423; A., 196.17 Chem. News, 1932, 145, 81 ; A., 968.18 Arch. Sci. biol., Russia, 1931, 31, 385; A . , 1932, 1168.l9 Bot. Archiv, 1931, 33, 172; A., 1932, 93274 BIOCHEMISTRY,6-hydroxy-acids and their lactones is given. Intermediate productsinclude certain unsaturated compounds.Examination of fungal mycelium reveals differences in carbo-hydrate composition which are related to the nature of the nutrient.Thus on a glucose substrate A . niger contains a high proportion oftrehalose and a small amount of mannitol. On media containinginvert sugar or fructose the proportions are reversed.30 hlnnnitolis also present in the mycelium of A . $fischeri and A . oryxce. Theproduction of ergosterol by these organisms 21 and by Y. puberulum 22is also recorded.A. G. POLLARDJ. PRYDE?* Obaton, Conapt. Tend. SOC. Biol., 1930, 105, 6’13; A., 1932, 651.21 L. M. Pruess, W. H. Peterson, and E. B. Fred, J . Biol. Chefn., 1932, 97,22 J. H. Birkiiishaw, R. K. Callow. and C. F. Fischmann, B;orhcin. J . , 1931,483; A,, 1065.25, 1977; A ., 1932, 185

ISSN:0365-6217    

DOI:10.1039/AR9322900239

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

GEOCHEMISTRY.GENERALLY speaking, the period under review has been one ofstleady advance in all the branches indicated in the Report for1930. Perhaps the most important development lies in the increas-ing application of chemical principles t o the description of rocksand mineral deposits. There has been a very substantial outputof physicochemical data for the oxide and other systems, so thatmany problems in igneous petrology, salt deposits, and ores cannow be discussed in ordinary chemical terms. In this way thetheory of chemical reactions in the earth's crust is assuming a moredefinite shape, and steps are being taken to avoid further extensionof the earlier arbitrary descriptive terminology, which has beengenerally regarded as unsatisfactory. Many new minerals havebeen described; but an outstanding feature is the review of theprincipal mineral groups.Pyroxenes (Sundius, Barth), amphi-boles (Winchell), tourmalines (Ward), zeolites (Hey), micas (Jakob),and other important divisions have been critically discussed, withmany additional analyses.In radioactivity, perhaps the most striking development is theconsistent determination of the age of certain minerals, withconsequent dating of the deposits in which they occur. Minera-graphic work includes descriptions of several famous ore-bodies, e.g.,the copper-bearing formation in N. Rhodesia ; the mode of formationof the characteristic structures is being followed up, and the studentnow has the assistance of text-books such as the " Lehrbuch " ofH. Schneiderhohn and the " opaque minerals " bulletin of M.N.Short.Formulation of the silicates continues to be discussed : in manycases new determinations of the unit cell contents have been made,but the interpretation is still troubled by uncertainty as to theextent of " proxy " substitutions : the spinels have been extensivelystudied, with results that fully establish the interchangeability ofcertain atoms. Another important discovery is the existence ofatomic groups, such as 0, in NH,NO,,l that appear to be capableof rotation; here the oxygens, like atoms in solid solution, arenot directly represented by X-ray reflexions.General Geochemistry.Spectroscopic studies have been made of the Katzenbuckelrocks by F. Schroder,la and of tourmaline, diopside, and rocksalt1 J.Arner. Chem. SOC., 1932, 54, 3766.la Jahrb. Min., 1931, [ A ] , 63, 216; A., 5952713 GEOCHEMISTRY .by G. 0. TTild.2 In coloureci minerals thc absorption spectmmchanges with the direction of vibration ; many minerals, especiallythose with uranium h a v ~ been studied by B. Lnnge and W. Eitel,“and by F. Coria.4Several new devices have been proposed for density work.W. Kratschmai has designed a new balance of Westphal type,but giving direct readings for density. A similar instrument byG. Scharffenberg has a circular beam with very widely separatedknife edges. New separating vessels for the centrifuge are givenby W. Kunitz and H. Miiller; S for heavy liquids by S. Klein.9J. L. Rosenholz and D. T. Smith have prepared tables for specificgravity and hardness of minerals.Piperine, n 1.63, is recommendedas a mounting medium by J. H. Martens.llM. M. Stephens l2 finds that some silver minerals may be etchedwith a powerful arc-light. For mineragraphy an important set oftables has been compiled hy M. N. 8hort,lS in n form similar to thewell-known tables for non-opaque minerals by E. 8. Larsen ; colour,hardness, anisotropy and etching properties are listed for the opaqueores, with a section on micro-rcacfions. ilnother importantcontribution is the secoiicl edition (much extended) of the “ Lehrhclider Erzmikrosliopic ” by €1. Sclmeidcrhohn and P. Iimndolir.(Berlin, 1931), supplementecl by ‘ * 1~rzmil;roslio~~ische Bestimnmngs-tafeln ” in a separate volumc.N. Bcreli arid A. Cissarzdiscuss the measurement of reflecting powcr. Microchemicalanalysis, both qualitative and quantitative, is described in Y.Emich’s “ Mikrochemisches Praktikum ” (Munich, 1931). Examplesare given by H. Mueber.16 A. N. Winchell’s ‘“Licro. charactersof . . . artificial minerals ” has been considerably enlarged in asecond edition (New York, 1931). New minerals are listed, withbrief descriptions, by L. 5. Spencer l G n in the .. 12th list of newmineral names ” and numerous physical data have been assembledby the same author.17Centr. Min., 1931, 254, 327, 430; 1932, 18; A., 493.Tsch. min. petr. Mitt., 1931, 41, 435.Ann. SOC. Sci. Bruxelles, 1931, [B], 51, 145; A . , 1931, 1145.Centr. Min., 1932, 221, 348.Ibid., p. 345.Ibid., p. 225. Ibid., p. 90.Ibid., 1931, 244.lo Rensselaar Poly. Inst., Eng. and Sci. Series, No. 34.l1 Amer. Min., 1932, 17, 198.l3 U.S. Geol. Survey, Bull. 825, 1031.l4 2. Krist., 1931, 76, 396; A., 1931, 587.l5 Ibid., 1932, 82, 438.16@ Min. Mag., 1931, 22, 614.l7 “Annual Tables of Constants. . . .” Extracts from vol. 7 (speciall2 lbid., 1931, 16, 532.l6 Centr. Min., 1932, 337.reprint) (Paris)HALLIMOND. 277Much attention is now being given to the distribution of theelements in the earth’s crust. V. M. Goldschmidt l8 and co-workers have produced a series of papers dealing with elementsindividually, such as gallium, boron, scandium, germanium (incoal). Tungsten in Bolivia l9 occurs mainly under lower temperatureconditions than tin-ores.Vanadium has a remarkably wide distri-bution ; it apparently accompanies titanium, and is present insmall amounts in sea-sand and meteorites, in titanomagnetite andin volcanic rocks, as well as in sediments (up to 0.01~o).20 J.Papish and C. B. Stilson21 find that gallium occurs in blendc,galena, etc., but not in some other zinc minerals such as calamine,smithsonite, zincit e.General studies of the distribution of elements have been madeby H. v. Kluber in “Das Vorkommen der chemischen Elementeim Kosmos ” (Leipzig, 1931) for meteorites, planets, and stars.G. Berg’s “Das Vorkommen der chemischen Eleinente auf derErde ” inevitably covers in part the same ground as the series byV. M. Goldschmidt (above). Strontium has a specially interestingdistribution; W.No1122 finds O.lyo (as oxide) in pyroxene andgreater amounts in felspars.Attention has been directed by H. S. Washington23 t o thepossibility that beryllium has been overlooked and included asaluminium, with consequent errors in the comparison of norm andmode for rocks. C. Palache and L. H. Bauer 24 report berylla invesuvianite (9.20%) , cyprine, and barylite, also in milarite.Many contributions have been made to the spinel problem, t owhich reference was made in an earlier report. W. Jander andW. Stamm 25 deduce from conductivity and diffusion measure-ments that some spinels are ionised while others show electronicconductivity. The form y-Al,O, has been studied by I>. S. Belian-kin and N. Dilaktorsky,26 who find that its constants differ fromthose for A1203 dissolved in spinel.T. F. W. Barth and E.Posnjak 27 find further evidence for “ variate atom equipoints ” ;see also F. Machatschki.28 Atom size may be measured by “radius”(W. L. Bragg, V. M. Goldschmidt) or “space-filling ” volumeNudi. Ges. Wiss. Gdttingen, 1931, 165, et ul. ; A., 39, 141, 248, 595, 926.F . Ahlfbld, Chem. Erde, 1933, 7, 121 ; A., 596.2o K. Jost, ibid., p . 177.21 Arner. Min., 1930, 15, 821; A., 1931, S17.22 Naturwiss., 1931, 19, 773; -4., 1931, 1391.23 Amer. Min., 1931, 16, 37.25 2. anorg. Chem., 1931,199, 165; A., 1931, 999.26 Centr. Min., 1932, 229.2 7 J . Wash. Acad. Sci., 1931, 21, 255; A . , 830.28 2. Krist., 1932, 82, 348.24 Ibid., p. 469; A., 1107278 GEOCHEMISTRY.(T.W. Richards, J. J. Thomson z9) ; W. Biltz 30 and others havecarried out an extensive study of molecular and atomic volumes,mainly on an additive basis. G. Natta31 has examined hydrogenchloride, bromide, etc., and finds relatively large atomic sizes forthe halogens. It is interesting to recall that the original halogenvolumes given by Wasastjerna depended on the experimental sideon a small size assigned to hydrogen in the dissolved halide.Oxide Xystems.G. W. Morey 32 has given a valuable discussion of silicate chemistrywith many references to earlier literature on synthesis, particularlyby the Geophysical Laboratory. Cr,O, and A1,0, form a continuousseries of mix-crystals ; and Si02-Zn0-A1203 (E. N. Bunting) yieldsZn,SiO,,ZnAl,O, and mullite, with bearing on the making of zinc-retorts.33 Solutions of sodium chloride under pressure have beenstudied by L. H.Adams and R. E. Hall.3* In Mg0-MgC12-Hz0,35brucite yields, with MgCl2,6H,O and solution, a magnesiancement. Many compounds in Ca0-Si02-A1203-H,0 have beendescribed in an extensive series of papers by S. Nagai,36 both a tatmospheric pressure and with high pressure and moderate temper-ature; sodium carbonate solution is used to separate the products.The same author, also W. Masgill, G. M. Whiting, and W. E. S .Turner,37 have studied the silicates formed by heating chalk andsilica. CaO-Na,0-,41203 38 yields two ternary compounds.The volatility of silica in steam is discussed by G. W. Morey.39C. J. van Nieuwenburg and H.B. Blumenda14* have volatilisedsilica in supercritical steam : kaliophilite is altered to leucite andorthoclase, while nephelite yields analcite and albite ; carbondioxide inhibits these reactions. Titanium and stannic oxides arenot volatile under these conditions, but molybdenum and tungstenThe sizes given by the c c radius”method are often quite at variance with the c c additive ” volumes ; cf. A. F.Hallimond, Min. Mag., 1927,21, 277; 1928, 21,480; 1929, 22, 70.29 Phil. Mag., 1922, 44, 657; 43, 721.30 2. anorg. Chem., 1932, 203, 277, etc.31 Mem. R. Accad. d’Italia, 1931, 2, 1.32 Annual Survey of Amer. Chern., 1930, 5, 457.33 E. N. Bunting, Bur. Stand. J . Res., 1931, 6, 946; 1932, 8, 279; A., 1931,34 J . Wash. Acad.Sci., 1931, 21, 183; A., 1931, 793.35 C. R. Bury and E. R. H. Davies, J., 1932, 2008.3ti 2. anorg. Chem., 1932, 206, 177, etc.J . SOC. Glass Tech., 1932,l6, 94.36 L. T. Brownmiller and R. H. Bogue, Bur. Stand. J . Res., 1932, 8, 289 ;39 G‘eophys. Lab. Paper, No. 786.40 Rec. trav. chim., 1931, 50, 989; A., 1931, 1381.1010 ; 1932, 547.A . , 574HALLIMOND. 279trioxides will react with lime to form CaMoO,, etc. ; copper is alsovolatile. Carbon dioxide under high pressure attacks the silicatesre~ersibly.~l K. Bito, K. Aoyama, and M. Matsui4, find thatcalcium carbonate dissociates a t about 915" under one atm. ofcarbon dioxide ; fresh crystals require a slightly higher temperature.The system K,O-CaO-SiO,, important for glass-making, has beendetermined by G.W. Morey, F. C. Kracek, and N. L. B~wen,*~and the behaviour of K,Si40, under pressure has been investigatedby R. W. Goranson and F. K r a ~ e k . ~ ~Systems containing iron react with platinum vessels ; in additionthe two iron oxides react with the furnace gas. Complete successin these experiments has not yet been obtained, but a number ofsystems have been investigated over a considerable range of con-ditions. By using electrolytic iron crucibles in nitrogen, N. L.Bowen and J. F. Schairer 45 have explored the system ferrous oxide-silica. Ferric oxide appears, up to 11%, which diminishes sharplyon addition of silica; all attempts t o produce FeSiO, failed(although iron-rhodonite is common in slags), MgO-FeO-Fe,O,in air a t one atm.has been investigated by H. S. Roberts and H. E.Merwin ;46 equilibrium is attained slowly, and the alundum crucibleswere protected by an adherent layer of the mixture; when homo-geneous, the preparation was treated by the usual quenchingmethod; one interesting feature is the formation of solid solutionsnot only between MgO,Fe,O, and iron oxide but between thatcompound and magnesium oxide, a further contribution to thecomplex problem of the spinels. J. H. Andrew and W. R.Maddocks 47 describe solid solutions of FeS in Fe,SiO,.The system potassium sulphate-water under pressure has beeninvestigated by L. H. Adam~.~8 G. Tunell and E. Posnjak49 havecompared the natural oxidation of sulphide ore-bodies with thehehaviour of the system Fe,O,-CuO-SO,-H,O (part) ; goethite,tenorite, brochantite, antlerite, and 3Fe,03,4S03,9H,0 were obtained.S. G.Lasky 49a discusses the application of the phase rule to iron oresin limestone.Several ternary compounds in Na,O-B20,-H,O have been pre-I1 W. Weyl, Glastech. Ber., 1931, 9, 641.42 J . SOC. Chem. Ind. Japan, 1932, 35, 191.43 J . SOC. Glass Tech., 1930, 14, 149; 1931, 15, 57; A., 1931, 1011.44 J . Physical Chem., 1932,36, 913.45 Amer. J . Sci., 1932, [v], 24, 177; A . , 997.46 Ibid., 1931, 21, 145; A., 1931, 310.47 J . Iron and Steel Inst.. 1932 [adv. copy] ; A., 997.4s J . Amer. Chern. Soc., 1932, 54, 2229 ; A., 810.49 J . Physical Chem., 1931, 35, 929; A., 1931, 800.49a Econ. Beol., 1931, 26, 486280 GEOCHEMISTRY.pared by U.Sborgi; 50 CaO-Ye0 has also been studied by J. Kon-arzewski 51 with reference to Portland cement. Thermal data forsilicates of Ca, Fe, Mg are given by W. A. Roth and H. T r o i t ~ s c h , ~ ~also by H. Wagner.53 V. A. Vigfusson 54 has prepared hydratedcalcium silicates. Further data for gypsum-anhydrite atre givenby R. Nacken and K. Fill,55 and also by L. Cha~sevent.~~ Lithi-ophilite (LiMnPO,) has been prepared by F. Zambonini and L.Malossi 57 in phosphoryl chloride vapour. Phosphates related tothe apatite group have been prepared by precipitation, as well asby heating a t 1100", by G. Trome1.58 A. Sanfourche arid J. Henry 59note a false equilibrium in the action of water on CaHPO,. Musco-vite 60 has been prepared hydrothermally by heating the colloidmixture in a pressure bomb for 5 days a t 300".Petrology.Rock analyses are very widely scattered in the literature, arid itis impossiblc to deal with them adequately in the present Report.They are mainly intended for descriptive purposes, though a certainproportion of papers on the igneous rocks are accompanied bytheoretical discussions on the mode of formation.A valuabletext-book on petrology has been prepared by F. F. Grout : " Petro-graphy and Petrology" (New York, 1932). The latter term isdefined to include the discussion of theory, and the book will givethe student a very clear account of the present state of speculationin this subject. Development has been hindered by a terminologywhich has not yet been successfully revised.Actually the totalnumber of petrological terms to-day is about 1300,60u including notonly all the rock names but the descriptive terms ; with the progres-sive abandonment of a substantial proportion of the names, thelist should reach manageable proportions. Throughout the workthe student is assumed to have a fully competent knowledge ofchemistry, physics, and mineralogy : there is a brief account ofpetrographical methods in the form of a series of problems, but thedegree of condensation in this part of the book may be gatheredGaxzetta, 1932, 62, 3 ; A., 341.6 1 Rocz. Chem., 1931, 11, 516, 607; A . , 1931, 1010, 1373.5 2 Arch. Eisenhuttenw., 1932-1933, 6, 79.5 3 2. anorg. Chem., 1932, 208, 1.54 Amer. J. Sci., 1931. [v], 21, 67; A., 1931, 310.5 5 Tonind.-Zfy., 1931, 55, 1194.5 6 Cowpt. r e d . , 1932, 194, 786.5 7 2. Krist., 1931, 80, 442; A . , 38.5 8 2. physikal. Ohem., 1932, 158, 422; 2. anorg. Chenz., 1932, 206, 227.5B Compt. rend., 1932, 194, 1940.6o ITT. Noll, Naturwiss., 1932, 20, 283.60a A. Hokes, " The Nomenclaturo of Petrology," 2nd Ed. (London, 1928)HALLIMOND. 281from the paragraph dealing with rock-analysis : ‘‘ Problem &Tomake a chemical analysis of a rock. Method--Refer to H. S.Washington. . . . ” It may be some time before the painstakingstudent is free to attack Problem 7 ! The descriptions are mainlybased on examples chosen from North American occurrences ;evidence for the operation of the principal rock-forming processeshas been clearly set out and the difficulties are not evaded.Butagain it must be emphasised that these chapters assume previoustraining, indeed there is some risk that so lucid a text-book mayencourage a superficial acquaintance with “ petrology ” in studentswho lack the necessary groundwork of the older sciences.“ Metamorphism ” by A. Harker (London, 1932) will be an essen-tial text-book for the more advanced student. Mineralogicalchanges produced by heating, chemical alteration, and pressureare systematically described, with many illustrative examplestaken mainly from British occurrences. The development of por-phyroblastic structures is traced with reference to the “ crystal-lising power ” of the mineral, which determines microstructures ofa type quite distinct from those due to the crystallisation-sequencein igneous rocks.More than 200 drawings are very effectivelyused in place of photomicrographs.Among numerous descriptions, mention may be made of papersby Romer,61 who describes the gas, incrustations, and dacitoidlavas of Mt. Pelke. Liparite from the Crimea,62 containing Fe 0.44,alk. 8.75%, might be used for glass manufacture. A. Holmes andH. F. Harwood 63 have given an extensive description of volcanicrocks from Uganda. Much discussion has recently centred uponthe question how far an igneous intrusion can assimilate the wall-rocks : s. R. Nockolds 64 describes the process in a granite-green-stone contact from the Isle of Man; other instances are given byH. H. Thomas and W. Campbell Smith,G5 basic xenoliths in aBrittany granite ; by H.C. Horwood,66 granite-gneiss and granite-limestone contacts in Ontario; by L. A. N. Iyer 67 for granites inIndia; also a detailed study of granite slate contacts in Cornwall,by A. Brammall and H. F. H a r w o ~ d . ~ ~ ~ Differentiation withoutcontamination has been studied by F. F. Osborne and E. J.61 Compt. rend., 1932, 195, 393; A., 1015.62 Trans. State Ins?. Test. Building Mat., 1930, 34, 33.63 Quart. J. Geol. SOL, 1932, 88, 370; A., 1015.64 Min. Mag., 1931, 22, 494; A., 1931, 1029.135 Quart. J. Geol. SOC., 1932, 88, 274.66 Trans. Roy. Soc. Canada, 1931, [iii], 25, IVY 227 ; A., 359.67 Rec. Geol. Surv. India, 1932, 65, 445; A., 1107.67a Quart. J . CTeol. Soc., 1932, 88, 171; A., 715282 GEOCHEMISTRY.Roberts,68 who redescribe theShonkinSaglaccolith ; by L. Jugovics,60for dacites in Bohemia ; and by A.Vendl,70 for Hungarian andesites.E. Lehmann 71 derives basanite, trachyte, etc., in Nyassaland froma basaltic magma, and a similar explanation is given for basicflows in West Greenland. 72General theory includes a discussion of the earth's interior byA. A. Bless,73 who estimates the temperature as lo5 degrees, androck-classifications by A. Johannsen 74 and E. TrOger.'5 A revisionof the minerals postulated in calculating the " norm " of a rockhas been proposed by T. F. W. Barth 75a and criticised by C. E.Tilley.76 P. Eslrola 77 objects that the idea of a lighter sial layeris not supported by the frequent occurrence of granites in thepre-Cambrian, which rather indicates crystallisation-differentiation.Much attention has been given to the composition of the residualliquids formed during the crystallisation of a granite : C.N. Fenner 78has pointed out that in some cases an increase in iron/magnesiaratio should occur, a fact which has not always been taken intoaccount; H. A. Powers 79 finds that in lavas from California theresidual liquid was enriched in iron. A general theoretical dis-cussion of this problem has been given by P. Niggli.80 Experimentsby R. W. Goranson 81 show that water, which becomes concentratedin the residue, has an important influence on the crystallisation ofgranite. Under 10 km. cover, a granite with 1% H,O would beginto crystallise a t 1025"; at 700" the residual would contain 6.5% ofwater, and would continue to crystallise till below 500", the resultbeing 85% granite, 10% aplite, 5% quartz veins. Under only4 km., the pressure will equal the hydrostatic head when the temper-ature falls to 950", so that liquid can then be expelled from thereservoir ; this, the author considers, might result in the formationof two fluid phases.O S Amey.J. Sci., 1931, [v], 22, 331; A , , 1931, 1265.G@ Tsch. min. petr. Mitt., 1932, 43, 156 : A., 1107.7O Ibid., 1932, 42, 491.Ibid., 1931, 41, 8.72 H. Nieland, Chem. Ede, 1931, 6, 501.7 3 Proc. Nut. Acad. Sci., 1931, 17, 225; A . , 1931, 81G.7 " A Descriptive Petrography of the Igneous Rocks " (Chicago, 193 1 ).i 5 Jahrb. Min., 1931, [ A ] , 62, 249; A., 1931, 1391.i 5 a Tsch.min. petr. Mitt., 1931, 42, 1 ; A., 1931, 1391.i 6 Ibid., 1931, 42, 1 ; 1932, 43, 68; A., 926.i7 Ibid., 1932, 42, 455; A., 715.7 8 Min. Mag., 1931, 22, 539; A., 1931, 1390.7 9 Amer. Min., 1932, 17, 253.Rec. trav. chirn., 1932, 51, 633; A . , 829.81 Amer. J . Sci., 1932, [v], 23, 227; 1931, 22, 483; A., 492HALLIMOND . 283RadioactivityRegular use is now being made of the P b : U and other ratios forcomputing the age of rocks and minerals. C, N. Fenner 82 obtains2779 x lo5 years for the age of a monazite crystal, agreeing wellwith the value for uraninite from the same quarry. Thucholitegives 250 x lo6 while 0. B. Muench finds 373 X lo6years for cyrtolite from Bedford, N.Y., and 571 x lo6 for that fromOntario.On the other hand, (Mlle.) E. Gleditsch and B. Qviller 85report unduly low values for uranothorites. Kolm, the Swedishuranium-bearing shale, is proved by R. C. Wells and R. E. Stevens 86to have an age of 458 x 106 years. G. Elsens7 and (Mlle.) E.Gleditsch and S. Klemetsen 88 contribute to the investigation ofactinium content. Lead in rocks is for the greater part not ofradioactive origin.89 A. Holmes 90 remarks that the total lead isfrom 4-50 times the generated lead ; lead ores can have been derivedfrom granitic magmas provided that the age of the earth is notmore than 16 x 108 years. C. S. Piggot 91 gives data for the radiumcontent of granites and of Hawaiian lavas. In granite the element isapparently chiefly associated with the Portuguese graniteshave yielded high radium values, and schists the lowest.93 Leadmay be included in crystals of sodium and potassium chloride;possibly it may occur in marine salts.94 Natural waters some-times contain radium,94* but it is largely eliminated by the presenceof sulphate ; water from petroleum wells, free from sulphate, had ahigher radioa~tivity.~~Minerals.Elements.-Few, if any, of the reported syntheses of diamondhave survived further tests ; M.K. Hoffmann 96 has repeated, with82 Amer. J . Sci., 1932, [v], 28, 327; A., 595.83 A. Faessler, Centr. Min., 1931, [ A ] , 10; A., 1931, 930.84 Amer. J . Sci., 1931, [v], 21, 350; A., 1931, 594.Phil. Mag., 1932, [vii], 14, 233; A., 1015.8 6 J . Wash. Acad. SC~., 1931, 21, 409; A., 1931, 1391.8 7 Chem.Weekblad, 1931, 28, 714; A., 139.89 G. von Hevesy and R. Hobbie, Nature, 1931,128, 1038; A., 139.91 Amer. J . Sci., 1931, [v], 21, 28; 22, 1 ; A., 1931, 332, 930.93 G. Costanzo, Rev. Ch;m. pura appl., 1931, [iii], 6, 17; A., 494,94 Xaturw+s., 1932, 20, 86.94a E.g., J. L. Bohn, J . Franklin Inst., 1930,210,461 ; P. Forjaz, Rev. Chim.pura app?., 1931, [iii], 6 , 1 5 ; J. A. Hootman, Amer. J. Sci., 1931, [v], 22, 453.95 W. Salomon-Calvi, Petroleurn, 1931, 27, 652; A . , 1931: 1145.g 6 Centr. Min., 1931, 214.Compt. rend., 1932, 194, 1731; A., 715.Ibid., p. 1039; A., 139.C. S. Piggot and H. E. Merwin, ibid., 1932, [v], 23, 49; A ., 139284 GEOCHEMISTRY.negative results, Hoff’s synthesis by means of the carbon arc inliquid air E.Reuniiig ‘37 discusses the origin of the rich diamonddeposits of S. W. Africa. Graphite is the subject of a monograph,“ Der Graphit” by 0. Kausch (Halle, 1931). Volcanic sulphurhas been analysed by W. Geilmann and W. Biltz;98 native sulphuroccurs (inside oxidised pyrite concretions) in nacrous scales of theform S 111, for which the name rosickyite is proposed by J. Sekanimx9gGold in the spatliic veins of Siegerland occurs in pyrite as well as inbismuth minerals, representing two stages of the hydrothermaldeposition.1 Gold in jacutinga, according to E. de Oliveira,2 is a,secondary deposit from acid chlorine-bearing solutions due to oxitl-ation of pyrite. Tn gravels gold has been reputed to “ grow again ”and P. W. Freise3 shows that small amounts of humic acid inground water will slowly dissolve gold in the absence of oxygen.Platinum in the famous “ Merensky horizon ” is shown spectro-graphically to occur in the sulphides in solid solution; in dunite,where sulphides are deficient, the platinum is in the metallic form,associated with chromite; only the sulphide ores give rise tosecondary platinum minerals on weat hering.Several primaryplatinum ores are analysed by A. G. Betechtin; Fe = 10-150/,,also Cu, Ir, Ni. Osmiridium is shown by 0. E. Zvjagintsev andB. K. Brunovski to contain substantial amounts of ruthenium,rhodium, etc., all in solid solution. Native silver has been shown by(Sir) H. C. H. Carpenter and M. S. Fisher to have a grain structuredepending on the temperature of deposition or subsequent heating.At Konigsberg silver occurs largely in secondary forms ; mercury,antimony, and nickel are present in some veins, which R.Stmenregards as of Temiskaming type. L. Tronstad9 concludes thittsilver may be deposited a t other points as well as the intersection oflodes with fahlbands. The genesis of the L. Superior copper-silverdeposits is discussed by K. Nishio,1° and by T. M. 13roderick.10a 11:. 13.Yapenfus l o b has described the “ bedded” copper ores of Nova Scotia.s7 Jahrb. Min., Beil.-Ud., 1931, [-4], 64, 775; A., 492.98 Z. anorg. Chem., 1931, 197, 422; A., 1931, 816.g9 2. Krist., 1931, 80, 174; A., 1931, 1390.* J. M. Huttenhain, Tsch. min. pstr. Mitt., 1932, 42, 355; A., 490.Ann. Acad. Brasil.Sci., 1931, 3, 151; A., 829.Metall u. Em, 1930, 27, 442; Econ. Geol., 1931, 26, 421; A., 1931, 1390.* Siebert Festschr., 1931, 257.5 Gorni Zhur., 1930,108, No. 1, 152; A., 140.Z. Krist., 1932, 83, 172; A., 1107.7 Bull. Inst. Min. Met., 1932, No. 330; A., 595.Tidsskr. Kjerni Berg., 1931, 11, 16; A., 1031, 331.Ibid., 1932, 12, 15, 28; A., 494.lo Proc. World Eng. Congr., Tokyo, 1931, 37, 499; A., 596.loa Econ. Geot., 1931, 26, 841, lob Ibid., p. 314HALLIMOND. 285Halides.-Salt domes are usually regarded as the result of theplastic flow of bedded salt deposits. In detail, however, they giverise to many difficult problems, such as the explanation of theirassociation with petroleum, and the origin of the associated calciumsulphate and sulphur; these points are discussed by M.Stuart,llL. Owen,l2 and E. de G01yer.l~ Salt pans in Brazil form on thePermian outcrops and are of three types, containing nitrates,carbonates, and ~u1phates.l~ F. Heidorn l5 records magnesiumfluoride with bitumen from the Zechstein. Radium fluoride isapparently present in isomorphous mixture in a radioactive fluoritedescribed by F. L. Hess.16 M. Kahanowicz l7 finds that bluefluorescence in sodium chloride is identical with that for metallicsodium, which has been suggested as the colouring matter. Halidephase-rule systems include that for (K, Na)Cl-H,O, by E. Cornecand H. Krombach,17 and the carnallite system by N. S. Kurnakow,D. P. Manoev, and N. A. Osokoreva.ls G. Silberstein l9 describes" pipes '' in limestolit.a t Hopunvaara, with magnetite and fluoritein alternate layers.XuZphides.-Staiinite has been recorded from TasmaniaYBo Spain,21and from British Columbia; 22 these are of interest in connexionwith the problem of cassiterite formation, and descriptions of Boliviantin veins have been given by G. W. Lindgren and A. C. Abbott 23(Oruro), F. Ahlfeld 24 (Uncia Llallagua), localities where the veinsare related to dacitic intrusive rocks. R. Herzenberg25 has de-scribed a new mineral lcoEbeckin (Sn2S,), cementing cassiterite(not confirmed by Ramdohr).The veins and telluride minerals of Kalgoorlie are describedin detail by F. L. Stilwell; 26 H. Borchert 27 gives etching lists fortellurides ; L. Toliody 28 has analysed hessite ; G. Vavrinecz 29describes antimony-rich enargite, from Hungary.X-Ray methodsl 1 J . Inst. Petrol. Tech., 1931, 17, 338; A., 1931, 931.l 2 Ibid., p. 334; A., 1931, 931.l4 F. W. Freise, Chem. Erde, 1932, '7, 24; A., 596.l5 Centr. Min., 1932, 356.l C Amer. J. Sci., 1931, [v], 22, 215; A., 1931, 1146.l7 Ann. Chim., 1932, [XI, 18, 5. l 8 Kali, Russia, 1932, No. 2, 25.Z o F. L. Stilwell, Proc. Austral. Inst. Min. Met., 1931, 1 ; A., 1931, 1029.21 S. Piiia de Rubies, Anal. Pis. Quim., 1931, 29, 699; A., 248.22 H. C. Gunning, Econ. Geol., 1931, 28, 215.23 Ibid., p. 453.2s Centr. Min., 1932, 354.26 W . Austral. Geol. Surv. Bull. 94, 1929; A., 495.27 Jahrb. Min., 1930, [ A ] , 61, 101.28 2. Krist., 1932, 82, 154; A., 595.29 B&n. KohBs. Lapok, 1931,64, 438; Chem. Zentr., 1936, i, 931.l3 Ibid., p.331.TSCJL. min. petr. Mitt., 1931, 41, 197.24 Ibid., p. 241286 GEOCHEMISTRY.have been used by F. A. Bannister and M. H. Hey 30 to determinethe minerals of S. African platinum concentrates, and for thedistinction of pyrite from m a r ~ a s i t e , ~ ~ the latter result confirmingthe earlier work of Allen and others. Bushveld nickel veins arediscussed by R. D. Hoffman.32" Unmixing " has been studied for covellite-chalcocite byA. M. Bateman and S. G. Lasky; 33 for chalcopyrite-blende andcubanite by E. Clar ; 34 and for chalcopyrite-cubanite-pyrrhotiteby WT. H. Newhouse.35 General descriptions of the correspondingmicrostructures have been given, especially by G. M. S ~ h w a r t z . ~ ~Several detailed accounts have been given of N.Rhodesian copperdeposits,37 which are usually regarded as impregnations from theneighbouring granite.Sulvanite, CU,VS,,~~ has been found in Utah. L. W. Staplesand C. W. Cook39 describe the molybdenite veins of Climax, Col.Oxides.-0. Miigge 40 describes a method for determining thetemperature of formation of quartz by heating a t 600". Amethystmines in Brazil are described by R. Brauns;41 according toJ. H ~ f f m a n n , ~ ~ amethyst colours can be imitated by exposingsilicate glasses to radium rays. Colour in spinel is shown byK. Schlossmacher 43 to be due to 1-4% of Fe (Coy Mn, Cr absent) ;intermediate colours are due to reduction.Galaxite, a new spinel, MnO,Al,O,, is described by C. S. Rossand P.F. Kerr44 with alleghanyite (5Mn0,2Si02). M. Donath45finds 2.42% ZnO in chromite from Ramberget; chromite fromTogoland has been analysed by N. IC~uriatchy.~~ H. H. Read47has described the formation of corundum-spinel xenoliths fromAberdeenshire.Water-soluble humus plays a great part in the formation of lakeiron ores ; 0. Aschan 48 has analysed the organic matter in Finnishlake waters. S. Goldsztaub 49 describes the formation of parallelgrowths of haematite on dehydrating natural ferric hydroxides ;30 Min. Mag., 1932, 23, 188; A., 1014.32 Econ. Geol., 1931, 26, 202.34 Centr. Min., 1931, 147.36 Econ. Geol., 1931, 26, 739.38 Arner. Min., 1931, 16, 667.42 2. anorg. Chem., 1931,196, 225; A., 1931, 579.4J 2. Krkt., 1931,76, 370, 377; A., 1931, 459, 545.44 rimer.Min., 1932, 17, 1 ; A., 1228.$ 5 lbid., 1931, 16, 484; A., 1107.4 6 Compt. rend., 1931, 192, 1669; A., 1931, 1029.4 7 Geol. Mag., 1931, 68, 446.48 Rrkiv Kenzi, Min. Geol., 1935, 10, No. 14, I ; d., 716.49 Comnpt. rmd., 1931, 193, 533; A . , 1931, 1390.31 Ibid,, p. 179.33 Ibid., 1932, 27, 5 2 .35 Amer. Min., 1931, 16, 334.37 See Econ. Geol., 1931-1932.39 Ibid., p. 1.41 Centr. Min., 1932, 97. 2. Krist., 1932, 82, 451; A , , 889KALLIMOND . 287the stability relations of these minerals have been discussed byG. Tunell and E. Posnjak 50 with reference to the theoretical con-clusions of J. W. Gruner. Further descriptions of the importantWabana iron ore have been given by A. 0. Hayes.51 Perhaps thegreatest iron ore masses in the world are the Brazilian itabirites,which occur as stratified pure red hzmatite and as micaceousschist.Z2 The peculiar banding of the L.Superior iron formationis attributed by R. J. Hartman and R. M. Dickey 53 to Liesegangeffects ; secondary ores are described by C. K. Leith.53aW. J. O'Leary and J. Papish 54 find up to 0.25% Cr in ruby.A. Achenbach 55 finds that artificial gibbsite passes into boehmiteabout 200" and dehydrates further at 350". W. Bussem andF. Koberich 56 describe the dehydration of brucite to periclase inparallel orientation. Analyses are given for pyroaurite 57 andhydromagnesite. 58 Microscopical studies of the manganese oxideshave been made by S. R. B. Cooke, W. Howes, and A. Emery,59also by J.Orcel and S. Pavlovitch.6O G. Natta and M. Baccaredda61find both Sb204 and Sb,O,, with calcium, in various antimonyochres. C. Zapffe has studied deposition of manganese fromwater supplies, sometimes by bacteria.61aCarbonates.-Bacterial precipitation of lime is described byH. Fischer, W. Bavendamm, P. Kalantarian and A. Petrossian,6zwho find a new bacterium, B. Xewanense. X-Ray investigationsby F. K. Mayer 63 show the presence of vaterite, changing to aragon-ite and calcite, in the shells of fresh-water snails. H. Wattenberg 64has suggested that liquid carbon dioxide could be formed under thepressures that obt'ain in ocean depths. Conditions for the pre-cipitation of dolomite have been discussed by 0. Biir 65 and H.Econ. Geol., 1931, 28, 337, 442, 783, 894; 27, 189; A., 1931, 800.51 Ibid., 1931, 26, 1.53 E.A. Scheibe, Arch. Eisenhiittenw., 1931-1932, 5, 391 ; A., 492.j3 J . Physical Chem., 1932, 36, 1129; A . , 492.j30 Econ. Geol., 1931, 26, 274.64 Anher. Min., 1931, 16, 3 4 ; A., 1931, 455.5 5 Chern. Erde, 1931, 6, 307; A., 1931, 1029.5 6 2. physikal. Chem., 1932, [B], 17, 310.57 E. Aminoff and R. Broom6, K . Svenska Vetenelcaps Akad. Handl., 1931,58 G. R. Levi and D. Ghiron, Gazxetta, 1932, 62, 218; A , , 696.5n Amer. Min., 1931, 16, 209.Go Bull. Soc. franp. Min., 1931, 54, 108; A., 1106.Atti R. A d . Lincei, 1932, [vi], 15, 389; A., 829.61a &on. Geol., 1931, 26, 799.G3 Chern. Erde, 1931, 6, 239; A., 1931, 596.64 Nature, 1933, 130, 26; A , , 539.66 Centr. Min., 1932, [A], 46; A., 1106.[iii], 9, No.5, 4 ; A., 1931, 1029.63 Zentr. Bakt. Par., 1932, 85, 431288 GEOCHEMISTRY.Udluft.66 E. Kohler 67 finds that schaumspat is a pseudomorphof dolomite after gypsum. J. Klarding has studied the roastingof ferrous carbonate, with formation of Fe,O,. Rocks consistingof dolomite, with zones of transition to magnesite and to siderite,occur in the S. U r a l ~ . ~ ~ Hydraked cupric carbonates, with malachite,have been prepared by V. Auger and Mme. P~ulenc-Ferrand.~~A curious observation has been made by F. Stober,71 who finds thaton imitating the formation of Fontainebleau calcites by growingsodium nitrate in sand, the rate of growth is very greatly increasedin the presence of the sand. Ik'. Taboury 72 has found efflorescenceof calcium acetate upon calcite specimens that had been stored inoak cases, due to acid from the wood.Silicates.-G.W. Ward 73 has carried out a very thoroughinvestigation of the black tourmalines ; optical properties aregiven, with several new analyses. While accepting the ordinarychemical replacements, he concludes that it would be futile topropose new molecules; a simple formula cannot be found.F. Machatschki 74 proposes for tourmaline the (physical) formulaXYSB,SiGH,03 where X = (Cu, Na), Y = (Li, Mg, &In, Fe, h l ) ;NaSi is replaceable by CaAl, and SiMg by AlAl.'' Green-earth " in the Tyrol occurs between volcanic rocks andlimestone ; it is compared by K. Hummel 75 with glauconite, and itsformation is attributed to halmyrolysis, i.e., submarine alteration,of igneous rock.Parase-piolitc has been found by H. Meixner 76in the Styrian magnesite deposits. Ashtonite 77 and cbinoptilolite 78are new aluminosilicates related to ptilolite. Zunyite fromGuatemala has been analysed by C. P a l a ~ h e . ~ ~ G. Liberi *O deducesthe formula 4Be0,Al,03,7Si0, for beryl from Erythrzea : danburitehas been described by Z. Harads.slE. S. Larsen and W. T. Schaller 82 describe serendibite from aG t iti76 8ti9i oi l727 3747 57 6" - , I7 88 08182Z. deut. geol. Ces., 1931, 83, 1 ; A., 1931, 1391.Chem. Erde, 1931, 6, 257 ;2. anorg. Chern., 1932, 207, 246.L. M. Miropolski, Bull. Acad. Sci. U.IE.iS.S., 1935, 820; rl., 1015.Compt. rend., 1932, 194, 78s ; A., 481.Chem.Erde, 1931, 6, 357; A., 1931, 1030.BUZZ. SOC. chirn., 1931, [iv], 49, 1289; ' I . , 3!J.Arney. Min., 1931, 16, 146; A . , 38.2. Krist., 1929, 70, 211; 71, 45; A., 1931, 595.Chern. Erde, 1931, 6, 468; A., 140.Tsch. min.petr. Mitt., 1932, 43, 182; A., 1107.E. Poitevin, Amer. Min., 1932, 17, 106.W. T. Schaller, ibid., p. 128; A., 1228.Ann. Chim. Appl., 1932, 22, 544; A., 1106.Z . Krist., 1931, 79, 349; A., 1931, 1266.Amer. Min., 1932,17, 457; A., 1228.., 1931, 596.i s Ibicl., p. 304HALLIMOND. 289limestone-granite contact. Dumortierite from India has beenaiialysed by S. K. Chatterjee.8,The hauyne group is particularly complex: T. F. W. Barth 84suggests physical formulz, and L. H. Borgstrom 85 proposes thesubstitution Ca,Na.D. S. Beliankin renames a sulphate-cancrinitewischnewite.86 Helvite has been analysed by H. B~wley.~'Sodalites have been aiialysed by K. Haraguchi 88 and by W.Brendler. 89 It is sometimes difficult to distinguish nepheline fromsodalite ; a method with X-rays, applicable to thin sections, has beendeveloped by F. A. Bannister,9o with several analyses by M. H. Hey ;similar methods are given for analcime and l e u ~ i t e . ~ ~ The scapol-ite group has been reviewed by L. H. Borg~trorn,~~ who regards themas isomorphous mixtures of type (NaAlSi,O,),, in which albitemay be replaced by anorthite, and NaCl by CaCO,, CaS04, &Na,CO,,&Na,SO,, Ca atoms replacing Na. F. Zambonini and V. Caglioti 93discuss new analyses of sarcolite.Among the hydrated silicates, H.Hueber and W. Frehg4 findthat " kupferpecherz " is a limonitic chrysocolla, isotropic. A.Schoep 95 concludes that plancheite from Katanga is variableand in part identical with shattuckite, in part with bisbeeite fromArizona ; katangite is chrysocolla. Willemite prepared by A. Karl 96 isfluorescent like the natural mineral. Bultfonteinite, 2Ca( OH,F),,SiO,,a new mineral from Kimberley diamond mines, is describedby J. Parry, A. F. Williams, and F. E. 'M7right.g7 S. Iimori,T. Yoshimura, and S. Hata 98 describe nagatelite, a new pegmatitemineral resembling allanite. Xanbornite 99 has the compositionBaSi205. Analyses have been made of lessingite, serandite,spadaite,, joaquinite, gadolinite, pumpellyite, bavenite., G.W.Bain has discussed the formation of chrysotile83 Rec. Geol. Surv. India, 1931, $5, 285; A., 247.84 Amer. Min., 1932, 17, 466.8 6 Centr. Min., 1931, 190; A., 249.87 J . Roy. Soc. W. Australia, 1932, 18, 83.8a Chikyu, 1928, 10, 262. 89 Centr. Min., 1932, [A], 42; A., 1106.Min. Mag., 1931, 22, 569; A., 1931, 1390.91 Ibid., p. 469; A., 1931, 595. O3 2. KriSt., 1931, '76, 481.O3 Compt. rend., 1931, 192, 967; A., 1931, 706.94 Centr. Min., 1931, 296. 95 Bull. SOC. franp. Min., 1930, 53, 375.O 6 Compt. rend., 1932, 194, 1743; A., 715.97 Min. Mag., 1932, 23, 145; A., 1015.98 Sci. Papers Inst. Phys. Chem. Res. Tokyo, 1930, 15, 83; A., 1931, 459.g9 A. F. Rogers, Amer. Min., 1932,17, 161; A., 1228.1 Trans. Inst. Econ. Min. Met., MOSCOW, 1930, Nos.44, 46.a Amer. Min., 1931, 16, pp. 344 and 231 resp.85 2. Krist., 1931, 76, 481; A., 140.Ibid., 1932, 17, pp, 308, 97, 338, 409 resp. ; A., 1228.Econ. Geol., 1932, 27, 39.REP.-VOL. XXIX. 290 GEOCHEMISTRY.Pyroxemx-N. Sundius4 has given a very full account of thetriclinic (Fey Mn, Ca) pyroxenes. Like the carbonates, they form aseries of incompletely miscible crystals, the intermediate membersbeing sobralite (Fe, Mn), bustamite (Mn, Ca), and hedenbergitc(Fe,Ca)SiO,. Bustamite does not form a complete series ofsolutions with rhodonite, and the optical properties are not continu-ous : it is suggested that bustamite is a ferriferous wollastonite;a wide gap between bustamite and wollastonite is attributed to theformation of pseudo-wollastonite a t higher temperatures. X-Raydata for enstatite are given by B.Gossner and F. Mussgnug;F. Rodolico gives analyses of diopside and tremolite from Italy.A pyroxene from S. Africa 7 contains 1.96% Cr,O,. T. F. W. Barth *records a titaniferous augite (TiO,, 3-75%), and has discussed theoccurrence of pyroxenes in basalt; this subject has been furtherexamined by S. T~uboi.~*Amphiboles.-Since the general acceptance of amphibole formulaewith (F, OH) as an essential constituent, the whole question of thestability relations of these minerals has come under review. Theformulation is further discussed by W. Kunitz lo and by E. Posnjakand N. L. Bowen,lOa who agree with the tremolite formula ofSchaller and Warren; the water is lost a t about goo”, when thecrystal changes to pyroxene and cristobalite ; a mineral obtainedfrom the dry melt proves not to be an amphibole.ll A.N. Winchell l2also has discussed the application of Warren’s formula to manyanalyses, with plots of the optical data. V. E. Barnes l3 shows thatgreen hornblende is converted into the “ basaltic ” variety byheating in air ; iron is essential to the change ; in hydrogen, greenhornblende is re-formed. Analyses of both varieties are given byT. 1~himura.l~ Formulae for the alkali amphiboles have beenproposed by H. Berman and E. S. Larsen,15 who deduce a limitedmiscibility. Lattice dimensions for the monoclinic amphiboleshave been determined by G. Greenwood and A. L. Parsons,16 andAmer. Min., 1931, 16, 411, 488; A., 1228.2.Krist., 1929, 70, 234; A., 1931, 595.Atti R. Accad. Lincei, 1931, [vi], 13, 705; A., 1931, 1391.H. O’Daniel, 2. Krist., 1930, 75, 575; A., 1931, 594.Jahrb. Min., Be&-Bd., 1931, [A], 64, 217; A., 494.Amer. Min., 1931, 16, 195; A., 494.Jap. J . Geol. Geog., 1932, 10, 67.lo Jahrb. Min., Bed.-Bd., 1930, [A], 60, 171; A., 1931, 595.loa Amer. J. Sci., 1931, [v], 22, 203; A., 1931, 446.l2 Amer. Min., 1931, 16, 250.l3 Ibid., 1930, 15, 393; A., 1931, 818.l4 Min. Mag., 1931, 22, 561; A., 1931, 1390.l5 Amer. Min., 1931, 16, 140; A., 38.lG Univ. Toronto Stud. Qeol., 1931, No. 30, 29; A., 493.l1 Ibid., p. 193HALLIMONI). 291analyses have been given for tremolite by A. L. Coul~on,~~ forbabingtonite by C. Palache and F.A. Gonyer,ls for hornblende byH. Heritsch,lg and for manganese-rich ferroanthophyllite by A.Orlov.20 Grunerite from Pierrefitte is described by H. V. Warren,21and N. Sundius 22 has discussed various grunerites, with analysesand optical properties, with respect to their manganese content.Veins of nephrite after pyroxene are described by H. Rose and J.Ilir~mme,~~ and specimens of various " jade " minerals (previouslyidentified mineralogically) have been tested by X-ray methods byP. L. Mer15tt.~~Micas, etc.-Fuchsite with 2.740/, Cr203 has been analysed byS. K. Chatterjee; 25 H. Meixner 26 has tested the various methodsfor determining chromium in mica, and finds earlier methods werenot reliable. A very important source of error in micas may be theomission to separate the rarer alkali metals; F.L. Hess and J. J.Fahey 27 have found 3.14% of caesium oxide in a biotite. J. Jakob 28continues his studies with several analyses of biotites and phlogo-pite; he considers that Ti never replaces Al or Si, but always 2Mg;apparently lime is again completely absent from these micas.F. C. Phillips 29 describes a margarite in which much of the lime hasbeen replaced by soda. Chlorites have been analysed by A. Goos-sens,30 S. Pavlovitch31 (from corundum rocks), and S. K ~ z i k ~ ~(from Tatra granite) ; also by G. L. D ~ c h a n g , ~ ~ who interprets 8 newanalyses as mixtures of serpentine, amesite, etc. J. Orcela foundfor ripidolite heated in nitrogen a sharp maximum at 780" due to2FeO + H20 = Fe,03 + H2.Chamosite, the chlorite of the ironores, was early obtained from Schmiedefeld ; the present generallyaccepted formula rests upon analyses of better material ; H. Jung 35has separated chamosite from this ore and obtains the formula5Al,0,,15R0,11Si02,16H,0, the accepted ratios being 5 : 15 : 10.l7 Rec. Geol. Surv. India, 1931, 63, 444; A., 1931, 595.l9 Centr. Min., 1931, 364.21 Min. Mag., 1931, a2, 477; A., 1931, 595.22 Amer. J . Sci., 1931, [v], 21, 330; A., 1228.23 Centr. Min., 1932, 301.25 Rec. Geol. Surv. India, 1932, 65, 536; A . , 1107.2 6 Centr. Min., 1931, 318.28 2. KriBt., 1932, 82, 271; A . , 715.29 Min. Mag., 1931, 22, 482; A., 1931, 595.30 Natuurwetensch. Tijds., 1931, 13, 119; A., 1931, 817.31 Bull. SOC. franc.Min., 1930, 53, 535.32 Bull. A d . Polonake, 1930, [A.], 536; A., 1931, 706.3a Chem. Erde, 1931,8, 416; A . , 1931, 1030.34 Bull. SOC. franc. Min., 1930, 52, 194; A . , 1931, 594.Chem. Erde, 1931, 8, 275; A., 1931, 1030.Amer. Min., 1932, 17, 295.2o Ibicl., 1932, 269.24 Amer. Min., 1932, 17, 497.27 Amer. Min., 1932, 17, 173; A., 1228292 GEOCHEMISTRY.X-Ray patterns distinguish it from thuringite. J. P. Arend36gives analyses of ooliths and gangue in the Lorraine ores.Felqmrs.-Methods for the identification of the felspars are de-scribed in detail by K. Chudoba, " Felspate 11. ihre prakt. Bestim-mung " (Stuttgart, 1932)) and H. Ebert 37 discusses the determinationof acid plagioclases. Anorthoclase from an Icelandic lava isdescribed by L.Hawkes and H. F. Harwood; 38 the surroundingglass must have uiidergone a subsequent change in composition withincrease in sodium oxide. Certain felspars apparently deviatefrom t'he standard formula; I). S. B e l i a n k i ~ ~ , ~ ~ who has collectedpreliminary data, fails to confirm Jakob's negative results forCaO and Ba0. A. G. MacGregor 40 uses cloudiness in the felspars asa criterion for thermal metamorphism.Clays.-Kaolin has been synthesised by W. No11 41 by heating theprecipitate in a pressure bomb a t 300". H. Jung42 shows thatkaolin can be partly dehydrated reversibly, yielding an amorphousproduct up to 550" ; the heat of hydration in this reaction has beendetermined by E. Klever and E. K ~ r d e s . ~ ~ Kaolin in shales isattributed by J.Kuh144 to the action of sulphuric acid. Japaneseacid clays have been further studied by several workers : the X-raypatterns resemble those of fuller's earth, attributed to a commoncrystalline clay-mineral ; thermal dehydration shows rapid loss at70-260" and a t 450-700"; basic and acid dyes are adsorbed,especially after removal of acid-soluble aluminium and iron. P. P.Kerr 45 discusses the presence of montmorillonite. General dis-cussions on clay are given by P. Kastner and I?. K. &layer, c. E.Marshall, P. H. Norton and F. B. Hodgdon, and R. Bradfield.46Vanadium occurs iiz red clay from De~onshire,~~ while the asso-ciated nodules contain as much as 13.96% of V,05.Zeolites.-M. H. Hey 48 gives a general review of the literature onzeolites ; 16 thomsonites analysed by him 49 show both replacementsCaAl-NaSi and Ca-Na,.Dehvdration of heulandit'e is described36373839404 14243444.546474848vCompt. rend., 1032, 194, 736, 990; L4., 360, 493, 595.l'sch. min. petr. Mitt., 1931, 42, 8 ; A . , 1931, 1390.Min. Mag., 1932, 23, 163; A., 1015.Centr. Alin., 1931, 356.Min. Mag., 1931, 22, 524; A., 1931, 1039.Naturwiss., 1932, 20, 366; A., 716.Chem. Erde, 1932,7, 113; A., 596.Yer68. Kaiser WilhelnL-Inst. Silikatforsch., 1930, 3, 17.Bull. Acad. Polonaise, 1931, [ A ] , 665.Amer. Min., 1932, 17, 192; Econ. Geol., 1931, 26, 153; A., 1228.See Abstracts under these names.G. E. L. Carter, Min. Mag., 1931, 22, 609; A,, 1931, 1390.Ibid., 1930, 22, 422.Ibid., 1033, 23, 51; A , , 715HALLTMOND. 293by P.Gaubert,so and P. G. Bird 51 has shown that zeolites can bedehydrated by freezing. Base exchange is used by G. Austerweil 52as a means of purifying salt preparations; when the exchangeresults in an insoluble compound the whole of a salt such as Na,CrO,may be removed (by a zeolite containing lead). Base exchange inpermutite has been extensively studied by E. Gruner 53 and others.Phosphates.-The apatite minerals have a peculiarly variedcomposition : S. B. Hendricks, M. E. Jefferson, and K. M. Mosley 54have analysed a variety of products, partly synthetic, and concludethat F in fluorapatite can be replaced by CO,, OH, SO,, SiO,, 0,C1, Br, or I , yielding minerals such as voelkerite, staffelite, collo-phanite, etc.X-Ray photographs show that animal bone is acarbonate apatite, which gains fluorine on fossilisation. Turquoiseanalyses have been discussed by H. J ~ n g . ~ ~J. Lietz56 has compared the constants for various analysedminerals in the pyromorphite group ; the order is pyromorphite-mimetite-vanadinite. A Spanish vanadinite is described byF. M. Martin.57 Intensely blue wavellite 58 contains 0.5% Cr20,.Veszelyite from Moravia 59 apparently forms an isomorphous serieswith arakawite and kipushite; new crystals of the latter have beendetermined by H. Buttgenbach.60 Leucophosphite is a new hydrousphosphate of K, Fe,E. Dittler and H. Hueber 62 have aiialysed rnottramite fromBolivia, for which they obtain a general formula that also agreeswith the Otavi descloizite.Psittacinite 63 has the composition2Pb0,2CuO,V20,,2H2O. Fervanite 64 is 2Fez03,2V,0,,5H20.Arsenoklasite is a new manganese arsenate from LBngban.65Legrandite, a complex zinc arsenate, is described by J. Drugman,M. H. Hey, and F. A. T. L. Walker G7 gives analysesof triphylite with colunihite, from a pegmatite in Manitoba.5 0 Bull. SOC. franq. Min., 1030, 52, 162.53 Compt. rend., 1931, 193, 1013.54 Z. Krist., 1932, 81, 352; A . , 494.f i 6 2. Krist., 1931, 77, 437; A., 1931, 817.5 7 Anal, Fis. Quim., 1932, 30, 377 ; A . , 530.G 8 A. Orlov, 2. Krist., 1931, 77, 317; A . , 1931, 707.59 V. Zsivny, ibid., 1932, 82, 87; A . , 595.Bull. Acad. roy. Be@., 1931, [v], 18, 43; A , , 494.61 E. S. Simpson, J .Roy. SOC. I+'. Australia, 1931-1932, 18, 69.63 Tscli. min. petr. Mitt., 1931, 41, 173; A . , 1931, 707.63 S. Taber and W. T. Schaller, Amw. Min., 1930, 15, 575; A . , 1931, 517.64 F. L. Hess and E. P. Henderson, ibid., 1931, 16, 273; A . , 38.65 G. Aminoff, K. Svenska Vetenskaps Akad. Handl., 1931, [iii], 9, No.6 o Min. Mag., 1932, 23, 17.5; A., 1015.6 7 Univ. Toronto Stud. (Xeol., 1931, No. 30, 9 ; A . , 493.51 Ind. Eng. Chem., 1932,24, 793.2. anorg. Chew., 1932, 204, 321, etc.6 6 Chem. Erde, 1932, 7, 77; A . , 596.5, 52; A., 1931, 1028294 GEOCHEMISTRY.Xulphates, etc.-M. H. Hey 68 finds that pink specimens offauserite from Hungary are really epsomite, stained with cobalt ;cupriferous melanterite 69 occurred in an ancient stope in Cyprus.Natural ferrous sulphates are discussed by R.Scharizer,?O andartificial voltaites by B. Gossner and E. Fell.71 Pickeringite,a hydrous sulphate of aluminium and magnesium, is describedby R. L. R~therford.'~ Other analyses include krausite andcreedite ; 73 castanite from California 74 and from Chuquicamata ; 75roeblingite from Franklin Furnace ; 76 pi~keringite.'~ C. Kuzniar 78describes secondary deposits of Glauber's salt in potash-bearingsediments.New minerals include Letovicite, (NHq)3H(S04)2,79 in coal-mine dumps ; Schairerite, Na,SO,,Na(F,CI) ; 8o Ardealite,CaHP04,CaS0,,4H20 ; Klebelsbergite, a basic antimonysulphate; 82 Glaucocerinite, basic sulphate of Zn, Cu, Al; 83" Alkanasul, " sulphate of A1 and alkalis. 84Detailsof the recently discovered pitchblende-silver deposit a t Gt,.BearLake in Canada are given by D. F. Kidd.86 Manganese compoundsinclude b i ~ b y i t e , ~ ~ coronadite 88 and romanechite ; 89 the newmineral magnesiosussexite, 2(Mg,Mn) 0 ,B203,H20, isomorphous withcamsellite, occurs in veinlets in the Michigan hzematite.wCuprotungstite has been analysed by W. T. S ~ h a l l e r . ~ ~68 Min. Mag., 1931, 22, 510; A . , 1931, 1029.69 Ibid., 1930, 22, 413; A., 1931, 191.70 2. Kriat., 1930, 75, 67 ; A., 1931, 459.71 Ber., 1932, 65, [B], 393.72 Amer. Min., 1932, 17, 401.73 W. F. Foshag, ibid., 1931, 16, 352; 1932, 17, 75; A., 139.74 A. F. Rogers, ibid., 1931, 16, 396; A., 140.7 5 M. C. Bandy, ibid., 1932, 17, 534.7 6 R. Blix, ibid., 1931, 16, 455; A ., 1107.7 7 R. L. Rutherford, ibid., 1932, 17, 401.713 Bull, Acad. Polonaise, 1931, [ A ] , 411 ; A . , 714.7 9 J. Sekanina, 2. Krist,, 1932, 83, 177; A . , 1015.81 J. Schadler, ibid., 1932, 17, 251.W. F. Foshag, Amer. Min., 1931, 16, 133.V. Zsivny, Math. Nat. Anz. Ungar. A b d . IViss., 1929, 46, 19; Chent.Zentr., 1930, ii, 3530.83 E. Dittler and R. Koechlin, Centr. Min., 1932, 13.84 5. Westman, Bol. Min. SOC. nac. Min., 1931,43, 433 ; Chom. Zentr., 1932,8 6 Amer. Min., 1932, 17, 234; A . , 1228.86 Econ. Qeol., 1932, 27, 145.87 H. Corti, Anal. Asoc. Quim. Argentina, 1931, 19, 109 ; A., 140.i, 673.J. Orcd, Compt. rend., 1932, 194, 1956; A., 716.F. Zambonini and V. Caglioti, ibid., 1931, 192, 750; A., 1931, 707.J. W. Gruner, Amer. Min., 1932, 17, 509HALLIMOND.295Water, etc.K. Higashi, K. Nakamura, and R. Harag1 have determined thespecific gravity and vapour pressure of sea-water at various con-centrations between 0" and 175". Copper is found by electrolysisto be about 10 mg. per cu.m. ; 92 ammonia in sea-water varies between0 and 48 mg. per cu.m. a t the surface, up to 350 mg. at 25 m. depth.93R. Willstatter 94 attributes the blue colour to copper ammines.Hydrogen-ion studies have been made by D. Goulstong5 andT. G. Thompson and R. U. Bonnar.96 Off Brest the reducing powerfor potassium permanganate is found by P. Chauchardg7 to risesomewhat in stormy weather; below 100 m. depth it rapidlydiminishes. The silica content is discussed by H. M. King,98 andN. W.Rakestraw 99 has determined phosphate, nitrate, and nitritecontents near Cape Cod.Formaldehyde in rain water is attributed by N. R. Dhar andA. Ram to direct formation in ultra-violet light. C. Srikantiagives the combined nitrogen in rain water at Bangalore. Rainanalyses a t Geneva, N.Y., for a 10-year period have been recordedby R. C. Collison and J. E. Mensching.3 Waters from 80 Japaneselakes have been analysed by S. Yoshim~ra.~ A. H. Wiebe5 hasdiscussed the bearing of dissolved phosphorus and nitrogen in theMississippi upon the plankton. The relation of iodine contents togoitre has been further investigated by J. Kupzis; adequacy ofiodine supply can be ascertained from the amount excreted. Thedistribution of iodine in water and coal is described by R. Wache ; 'iodine is without effect as a fertiliser, but is assimilated.E. Schantl*records 0.015% of magnesium iodide in well waters from the E.Indies. Many spring waters have been analysed. Picon9 hasg1 J . Soc. Chem. Ind. Japan, 1931, 34, 7 2 ~ ; A., 1931, 1265.g2 W. R. G. Atkins, J . MarineBiol. ASSOC., 1932, 18, 193; A., 714.s3 H. R. Seiwell, Ecology, 1931, 12, 485; A., 1931, 1145.94 Natumuiss., 1930, 18, 868.95 J . Proc. Roy. SOC. N.S.W., 1931, 65, 43; A., 247.96 Ind. Eng. Chem. (Anal.), 1931, 3, 393; A., 1931, 1389.9 7 Compt. rend., 1932, 194, 1256; A., 594.98 Contr. Canadian Biol. Fish., 1931, 7, Nos. 8-11, D, Nos. 1-4, 129-137.Science, 1932, 75, 417; A., 594.Mysore Univ. J., 1930, 4, 195; A., 1931, 594.New York State Agric.Exp. Stu. Tech. Bull., 1932, No. 193; A., 829.P m . Imp. Acad. Tokyo, 1932, 8, 94; A., 594.Science, 1931, 73, 652; A,, 1931, 930.Latvij. Univ. Raksti, 1930, 1, 425; A., 1931, 331.Mitt. Lab. prews. geolog. Landesanst., 1931, No. 13,43; Chem. Zentr., 1931,Chem-Ztg., 1932,56, 341; R., 594.Compt. rend., 1932,194, 1175; A., 594.1 Nature, 1932,130, 313; A., 1106.ii, 981296 GEOCHEMISTRY.investigated the organic carbon content, which is not directlyrelated to the results with potassium permanganate. Electricalconductivity tests are discussed by P. S. Tutundgie,lo and byE. Bovalini and E. Vallesi,ll who find the method useful withincertain limits as a guide to the dissolved matter. Muds have beenstudied by D. M. Reid,12 H. B. Moore,13 and others, with referenceto pH and content of phosphate, oxygen, etc.Work on natural gasesincludes several discussions of the hydrocarbon contents ; kryptonand xenon are estimated by N. P. Pentchev l4 in several Bulgarianga,ses.Soils.Soilcolours have been classified by N. A. Archangelskaya,16 usingOstwald's colour disc. There are numerous papers describing soilvarieties, which it is only possible to summarise in brief. Specialsoils result from the weathering of volcanic tuffs, loess and laterite ;in other cases vegetable decay products are dominant, forming peaty,pine, and other special types. Several soil surveys are recorded fromAustralia, the Nile, and Eastern Europe.H. Keller15 describes methods of soil charting in U.S.A.Coal.A.Duparque l7 considers that most coking coals are producedfrom lignin, bituminous coals from cutin ; anthracites belonging tothe latter class differ from the others. R. Lieske and K. Winzer l8also support the lignin theory, and G. Stadnikow l9 finds well-preserved lignin in shale. On the other hand, P. Krassa20 findsthat in fungal decomposition of wood, lignin is destroyed. Theaction of bacteria on cellulose is discussed by F. Fischer 21 and S. A.Waksman,22 while specific organisms in coal are described by R.L i e ~ k e . ~ ~ Base exchange involving the roof-clay has been suggestedas affecting the seams, but this is discounted by W. H. A. Pen~eler.~*lo Bull. Xoc. chiin. Yougoslav., 1931, 2, 77; 1932, 3, 33; A., 829.l1 Ann. Chim. Appl., 1931, 21, 51; A., 1931, 458.l2 J.Marine Biol. ASSOC., 1932, 18, 299; A., 714.l3 Ibid., 1931, 17, 325; A., 1931, 930.l4 Compt. rend., 1931, 192, 691; A., 1931, 594.l5 2. Pflanx. Diing., 1932, 24, A., 38.l6 Trans. Dokuchaiev Soil Inst., 1932, 6, 197; A., 110s.l7 Comnpt. rend., 1931, 192, 1472, 1257.Brennstoff-Chem., 1931, 12, 205; A., 1931, 931.l9 Ibid., 1932, 13, 547; A., 1015.2o Angew. Chem., 1932, 45, 21; A., 360.21 Proc. 111 Int. Conf. Bit. Coal, 1932, 2, 809; A., 1107.22 Brwmstoff-Chem., 1932, 13, 241 : A., 1016.2 3 Ges. Abhandl. liennt. h'ohle, 1930, 9, 27 ; A., 350.24 N.Z. J. Sci. Tech., 1931, 12, 284; A., 1931, 951, 1030HALLIMOND . 297A critical review of the published theories of coal formation is givenby E. Bed, A. Schmidt, and H.K o ~ h . ~ ~Petroleurn is regarded by A. I?. von Stah126 as related to theoccurrence of hydrogen sulphide springs, which are attributed tothe decomposition of proteins. K. Kobayashi 27 assigns the originof Japanese petroleum to the distillation of buried fish remains byvolcanic action under the sea, followed by absorption in acid clays.Chemical aspects of petroleum formation have been discussed byS. C. Lind.2*Contributions to the description of coal have been made by H.B r i g g ~ , ~ ~ who finds a graphical relation between the oxygen andcarbon contents of fusain, etc. Resin in coals is described by K. A.Jurasky 30 and H. Steinbrecher ; 3l E. Hoffmann and H. Kirchberg 32give a detailed account of resin inclusions in a Ruhr coal. Browncoals containing fibrous lignite, residues of the bark of conifers, aredescribed by' W. Gothan and Benade.33 Contrary to views expressedby E. Berl and others (above), G. Stadnikow3* describes a Siberiancoal seam, free from metamorphism, in which the upper layers aretypical brown coals, the lower being bituminous, suggesting thetransformation of brown coal into bituminous.Meteorites.Small pieces of siliceous glass known as tektites have been foundin Indo-China, Malay, North Borneo, and the Philippines; thecomposition is remarkably uniform, with about SiO,, 70 ; A1203, 12 ;FeO, 5% etc., and they are believed by A. Lacroix 35 to be of meteoricorigin. A. R. Alderman36 has described meteor craters fromHenbury, Australia; glassy fused rock was found, with largenumbers of iron fragments. Among meteorites recently describedmay be mentioned an iron meteorite from containing over16% of nickel, an amount also found in the Hoba (Grootfontein)25 Angew. Ghem., 1932, 45, 517 ; A., 1016.z G Petroleum, 1931, 8, 145; A., 1931, 460.2 7 J . SOC. Chenz. I n d . Japan, 1931, 34, 102.z 8 Science, 1931, 73, 19; A., 1931, 332.2Q Proc. Roy. SOC. Edin., 1932, 52, 195; A., 716.3o Brennstoff-Chem., 1931, 12, 161 ; A., 1931, 515.31 Ibid., 1931, 12, 163; -4., 1931, 818.32 Ibid., 1930, 11, 389.33 Braunkohle, 1930, 29, 274; A., 1931, 60.34 Brennstoff-Chem., 1932,13, 101 ; A., 597.35 Compt. rend., 1930, 191, 893; 1931, 192, 265, 1685; A . , 1931, 1146;3G Min. Mag., 1932, 23, 19.38 Amer. J . Sci., 1931, [v], 22, 360.1932, 1028.K 298 GEOCHEMISTRY.meteorite,39 which is the largest known. Other irons are describedby H. H. Nininge~-,~* L. L. F e r m ~ r , ~ l C. Palache and F. H.G ~ n y e r , ~ ~ D. R. Grantham and F. O a t e ~ . ~ ~A. R. Crook and 0. C. Farrington 44 describe a meteorite with high(Fe,Mg)O. A pallasite from Central Australia 45 contains fragmentalolivine ; E. S. Simpson and D. G. Murray 46 describe a siderolitecontaining large crystals of dark olivine and greyish-white enstatite.A fragment from S. E. Arabia described by W. Campbell Smith 47has the same minerals in choiidrules with some glass and felspar ; ina special method of analysis by M. H. Hey the metals are separatedby heating the powder in a current of dried chlorine.A. F. HALLIMOND.39 L. J. Spencer, Min. Mag., 1932,23, 1; A., 369; also S. G. Gordon, Yroc.40 Amer. J . Sci., 1931, [v], 22, 69; Aneer. Min., 1932, 17, 221, 396; S.,41 Rec. Geol. Survey India, 1931, 65, 161 ; A., 1931, 1265.42 Amer. Min., 1932, 17, 357.43 Min. Mag., 1931, 22, 487; A., 1931, 1028.44 Trans. Ill. Acad. Sci,, 1930, 22, 442; A., 1931, 1389.4 5 L. J. Spencer, Min. Mag., 1932,23, 38; A., 359.c6 Ibid., p. 33 ; A . , 359.4 7 Ibid., p. 43 ; A., 359.Acad. Nat. Sci. Philadelphia, 1931, 83, 251.1230

ISSN:0365-6217    

DOI:10.1039/AR9322900275

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

SUB-ATOMIC PHENOMENA AND RADIOACTIVITY.THE important work of the two years (1931-32) under review hasagain for the most part been physical in nature; it has been aneventful time for nuclear physics. A new, possibly ultimate,particle, the neutron, has been discovered, and it has already provedto be a useful weapon in investigations on nuclear structure; ithas been eagerly seized on by theorists interested in the structureof the atom. It has been found that protons when generated withsufficiently high velocities may bring about nuclear disintegrationby bombardment similar to that effected by the a-particle. Theneutron may also act as a projectile in a similar way. Many newisotopes of non-radioactive elements have been found, and theirmasses determined with a greater exactness than heretofore.Inthis work the magnetic-spectrograph and the ordinary spectroscopeare assisting the mass-spectrograph more and more as instrumentsof investigation ; the most remarkable isotope found during theperiod, that of hydrogen with a mass of 2, falls to the credit ofband-spectrum analysis. This combination of methods appearsto be so promising as probably to render superfluous in the nearfuture the older chemical methods of determining atomic weights.There has been a considerable advance in knowledge of the originof the y-ray, especially in its relation to the rare, high-velocity,a-particle ; also of the properties of the penetrating radiation,although its exact nature and origin still elude investigators. Onthe chemical side, the simplicity that ascribed all a-particle radio-activity to atoms of high atomic number has been surprisinglydisturbed in two ways.Element 87, apparently without detectableradioactivity, has been detected both by X-ray analysis and bythe magnetic-spectrograph, while samarium of atomic number 62has been found to be radioactive, expelling cc-particles.Radioactivity of Samarium.G. von Hevesy and M. Pahl1 have made preliminary observationson the radioactivity of the rare-earth element samarium (at. wt.150.4). This is of the a-particle type ; consequently, samariumis the first element outside the range of heavy elements thallium-uranium to show this type of activity. A layer of samarium oxidehas an activity of about one-third of that of a thick layer of potass-ium chloride of equal surface.The radiation is reduced to half-Nature, 1932, 130, 846300 SUB-ATOMIC PHENOMENA AND RADIOACTIVITY.value by aluminium of thickness 1.3 v. Preparations from differentsources showed the same specific activity. Chemical purificationindicated that the activity is not due to known radioactive elements ;it is suggested, however, that it may be due t o the very rare element61, to which i t is chemically very similar.Discovery of Eleinerht 87.Despite the extreme unlikelihood 2 of the existcnce of clcments85 and 87 in nature, on account of the known instability of theneighbouring elements 88, 86, and 84, two pieces of evidence havebeen put forward to support the existence of the missing memberof the alkali metals.worked up 10 kg.of samarskite rich in uranium, containing rubidium and czsium,so as to concentrate the last. The X-ray lines M c c ~ , L a l , L M ~ , Lp,, andL-q, calculated from Moseley’s diagram for element 87, were foundin the concentrate 011 excitation in a Siegbahn apparatus of highdispersion ; the Lp, line, for example, calculated to be 0.8524, wasfound as 0.853 A. The element is regarded as non-radioactive orvery feebly radioactive ; radioactivity, however, has yet to bestudied in detail. L. L. Barnes and R. C. Gibson4 have foundindependent evidence of the new element by examining with aDempster magnetic-spectrograph alkali sulphates known fromX-ray examination to contain traces of element 87.A mass of220 f 1 was the only one which could not be assigned to knownelements. Now it is known on general grounds that the isotopesof element 87 would be 221 and 223 or 221 and 219, an element ofodd atomic number having a maximum of two isotopes each ofodd atomic mass. The mass found is therefore confirmatory ofthe existence of the new element, which can thus be provisionallyassigned masses of 219 and 221 or, if simple, a mass of 219 or of221. F. Allison, (Miss) E. R. Bishop, A. L. Sommer, and J. H.Christensen 5 have described experiments with a magneto-opticalmethod, depending on the time-lag differences of the Faradayeffect behind the magnetic field, on solutions of minerals. Insolutions of pollucite and lepidolite, minima were observed at-tributed to element 87.Six minima are considered to indicatethe probable existence of element 85 also. They have sufficientconfidence in their observations to give names to these two elements,5. Papish and E. WninerAnn. Reports, 1928, 25, 317.J . Amer. Chem. SOC., 1931, 53, 3818; A., 1931, 1348.J . Amer. Chem. SOC., 1932,54, 613 ; A., 317 ; F. Allison and E. J. Murphy,Physical Rev., 1930, [ii], 36, 1097. See ibid., 35,285 ; A., 1931, 1391 ; J . Amer.Chem. SOC., 1932, 54, 405, 616; A . , 353, 355.* Physical Bev., 1932, [ii], 40, 318RUSSELL . 301but this is not yet shared by other workers . Preparations foundt o contain comparatively large amounts of element 87 by themagneto-optical methods were found not to contain i t by X-rayexamination.3 Further.when the method has been applied in aregion where the results are well attested. as for example to thecomplexity of copper or tantalum. 5 5 '9 l9 the results are a t variancewith those obtained by the mass.spectrograph . It is extremelynnlikely also that an element of odd atomic number. like number55. has more than two isotopes .Isotopes and JInss.&ertra .During the period knowledge of the isotopic composition oftwenty-one elements has been extended.' The results are sum-marisecl in Tables I and I1 . In thc latter. inem atomic weightsTABLE I .MinimumAtomic number of Masses (nearest integer) of isotopesElement . number . isotopes . in order of abundance .Hydrogen ......... 1 2 1. 2Beryllium ......... 4 2 9.8Neon ............... 10 4 20.22.21. 23Scandium ......... 21 1 45Rubidium ......... 37 2 85. 87Strontium ......... 38 3 88. 86. 87Niobium ............ 41 1 93Caesium ............ 55 133Barium ............ 56 4 138.137.136. 135Tantalum ......... 7 3 1 181Rhenium ......... 75 2 187. 185Osmium ............ 76 6 192.190.189.188.186. 187Mercury ............ 80 0 202.200.199.201.198.204.196.Thallium ......... 81 2 205. 203Lead ............... 82 8 208.206.207.204.209.210.203.205.Uranium ......... 92 1 238TABLE 11 .Ruthenium ...... 44 (y) 102.101.100.99. (98). 96197. 203Calculated InternationaAtomic Packing atomic weight atomicElement . number . fraction . (0 = 16) . weight . 7aLithium ............... 3 - 6.928 & 0.008 6.94Boron ..................5 - 10.794 & 0.001 10.82Scandium ............ 21 - 7 44.96 A 0.05 45.10Zinc .................. 30 - 9.9 65.38 -J: 0.02 65.38Niobium ............... 41 ca . - 8 92.90 & 0.05 93.3Ruthenium ......... 44 ca . - 6 101.1 101.7Tin ..................... 50 - 7.3 118.72 f 0.03 118.70Caesium ............... 55 - 5 f 2.0 132.92 0.02 132.81Tantalum ............ 73 ca . - 4 180.89 i 0.07 181.4Osmium ............... 76 - 1 4 2.0 190.31 4 0.06 190.8Thallium ............ 8 1 1.8 5 2 204.41 & 0.03 204.39Rhenium ............ 75 - 186.22 0.07 186.316 (Miss) E . R . Bishop. PhysicaE Reu., 1932.40. 16; A., 554 .J . Amer . Chem . SOC., 1931. 53. 1627 . 7u J., 1933. 11 5 302 SUB-ATOMIC PHENOMENA AND RADIOACTIVITY.of twelve elements, calculated from knowledge of the number ofisotopes, their relative abundance, and their packing fractions,are compared with the International values (0 = 16).The new isotope of hydrogen was found by H.M. Urey, F. G .Brickwedde, and G. M. Murphy.8 If isotopes H2 and H3 exist,it is expected thermodynamically that they should be concentratedwhen hydrogen is evaporated near the triple point. In specimensso concentrated, faint Balmer-spectrum lines were found a t thecalculated positions for H2 as broad doublets after an exposure400 times the normal one. The abund-ance of H2 to H1 in ordinary hydrogen was estimated as 1 : 4000.W. Bleakney found this ratio in ordinary electrolytic hydrogenas 1 : 30,000 & 20%. H. Kallmann and W.Lasarev lo found theabundance of ions of mass 3 to those of mass 2 a t low pressuresby a spectrographic method as 1 : 4000. Working with enrichedhydrogen, K. T. Bainbridgell determined the mass of the newisotope as 2.01351 f 0.00018 (0l6 = 16) by comparing the positionsof HiH2+ and He+ on a microphotometer record; he deduced thebinding energy of H2 according as it is imagined as built up of twoprotons and one electron or one proton and one neutron. N. S.Grace l 2 deduced theoretically the mass as 2.0113 f 0.0012. E.W. Washburn and H. C. Urey13 found that H2 was easily concen-trated by the fractional electrolysis of water; the residual waterof cells which have operated for a few years contained a markedincrease in abundance of H2 relative to H1.In the infra-redabsorption spectrum of hydrogen chloride, band lines correspondingwith H2CP5 and HVP7 have been found by J. D. Hardy, E. F.Barker, and D. M. Dennison 14; the abundances of H2C1 in ordinaryand in enriched hydrogen chloride were found to be 1 : 35,000 and1 : 3500 respectively and the mass of H2 was deduced as 2-01367 &-0.0001 in satisfactory agreement with other provisional values.The ease with which H2 can be concentrated in ordinary hydrogenmarks it off sharply from all other isotopic mixtures; the result isto be expected in view of the relatively enormous difference betweenthe two isotopic masses. That H2 could exist at all would havebeen regarded as most extraordinary had not the neutron l 5 almostsimultaneously been found.Although H3, He3, and He5 have been sought and not found:Physical Rev., 1932, [ii], 40, 1 ; A., 554.@ Ibid., 41, 32; A., 894.lo Naturwiss., 1932, 20, 206, 472; A , , 442, 790.11 Physical Rev., 1932, [ii], 42, 1; A., 1185.l2 J. Amer. Chem. Xoc., 1932, 54, 2562; A., 790.l3 Proc. Nut. Acad. Sci., 1932, 18, 496; A., 894.lP Physical Rev., 1932, [ii], 42, 279.l5 J. Chadwick, Nature, 1932, 129, 312; A., 443.No trace of H3 was foundRUSSELL. 303there is some evidence for Bes. W. W. Watson and A. E. Parker l6found weak satellites in the band spectrum of beryllium hydridewhich they ascribe to Be8; the relative intensities of the hydridesof Be8 and Be9 were estimated as 1 : 2000. A fourth isotope ofneon, Ne23, is claimed by G. Hertz.17 He succeeded in raisingthe ratio of Ne20 to Ne22, normally 10 : 1, to 100 : 1 and in loweringit to 10 : 8, by a diffision process.In a mixture of the latter ratioNe23 in addition to Ne21 was indicated by mass-spectrographicbut not by optical methods. This result, if corroborated, would bea remarkable one. Isobares of odd atomic weight are rare andthe mass 23, common to neon and sodium, would have the addeddistinction of being the lightest isobare known. The remainderof the results of Table I are due to F. W. Aston, obtained oftenby ingenious and unexpected means in the face of great experimentaldifficulties. (Thus, rhenium heptoxide failed to give mass lineseither as vapour or as solid. When gold chloride was excited inthe tube containing rhenium oxide on the walls, rhenium lines wereobtained in great intensity in absence of gold lines.Again, theintensity of oxygen lines was greatly enhanced by exciting themin a mixture containing helium.) Scandium,l8 niobiurn,lg czsium,20tantalum,lg and uranium21 have been found to be simple. Thecontroversy22 about the true atomic weight of czsium seems nowto be decided against the chemical methods. K. T. Bainbridge,23using Dempster’s method of analysis, has shown that the abundanceof a second isotope must be less than 0.3% of that of Csl@; F. W.Aston,20 by producing anode rays of caesium and gas rays of xenonin the same tube, compared their masses to 1 part in lo7 parts andproved conclusively that the packing fraction of caesium has anormal value; his result is given in Table 11.A similar disputeabout tellurium is not yet settled. F. W. Aston’s 24 value, 128.04,may be too high. 0. Honigschmid’s 25 new determination byanalysis of TeBre, 127687 -+ 0.019, is in agreement with the Inter-national value. There is a possibility that minor and light isotopesof tellurium 26 may bring down the higher value. The results onl6 Physical Rev., 1931, [ii], 37, 167; A., 1931, 403.l7 Naturwiss., 1932, 20, 493; A., 790.l8 Proc. Roy. Soc., 1932, [A], 134, 571; A., 210.l* Nature, 1932, 130, 130; A., 895.*O Ibid., 1931, 127, 813; A., 1931, 783.21 Ibid., 128, 725; A., 1931, 1349.22 Ann. Reports, 1928, 25, 305.23 Physical Rev., 1930, [ii], 36, 1668; A., 1932, 6.24 Ann. Reports, 1926, 23, 280; see A., 1925, ii, 618.25 Natumiss., 1932, 20, 659; A., 980.26 K.T. Bainbridge, Physical Rev., 1932, [ii], 39, 1021304 SUB-ATOMIC PHENOMENA AND RADIOACTIVITY.scandium, niobium, and tantalum suggest (Table 11) that thechemica.1 atomic weights are in each case a little too high. Thesimplicity of uranium is provisional ; no second isotope of abundancegreater than 2% of U238 could be detected. Rubidium hasbeen found to have its expected composition; a third isotope hasbeen found for strontium l8 and a fourth for barium.18 Ruthen-ium 27 and osmium 27 were each found to have six isotopes; theabundance of Rug8 is not yet decided. Rhenium 28 and thallium 18, 21both have their heavier isotope in greater abundance, thus differingfrom all other complex elements of odd atomic number greater than7.Two minor isotopes have been found for mercury29 and fourfor lead.3o J3glg6 is certain, Hg203 probable ; the former's abundanceis approximately O.Ol%, the latter's 0.006%. Of the four newlead isotopes, Pb203 and Pb205 are not certain; Pb207 and Pb2l0are related in abundance to Pb2OS as 19 : 1 : 250 according to P.W. Ast~n,~O or as 8 : 1 : 200 according to K. M ~ r a k a w a . ~ ~ Pb204has been found also by H. Schiiler and E. G. Jones 32 in the hyperfinespectrum of ordinary lead. If Pb203 and Zrg6 be confirmed, themass 203 will share with mass 96 the rare property of belongingto three elements : Hg203, TlZo3, PbZo3 and Zr", Mog6, Rug6, re-spec t ively .In Table I1 all the results except that for boron have been obtainedby F.W. Aston. There has been difference of opinion on t'heabundance ratio Li7 : Li6. From band-spectrum work W. R. vanWijk and A. J. van Kceveringe33 find the value 7.2. On themass-spectrograph F. W. Aston 34 found 10.2 & 0.5, which is close to14.9, obtained by M, Aforand35 with a heated anode, and to 10.5,obtained by H. Schiiler 36 from hyperfine structure of the spectrumof Li+. It is likely that the variation in intensities of spectral linesdue to Li6 and Li7 respectively, with the conditions under whichthey are excited, as found by G. Nakamura and T. S~hidei,~' ispartly the cause of the above differences. This does not occurwith positive rays.38 The atomic weight of lithium calculated2 7 Nature, 1931, 127, 233; A., 1931, 280.29 Ibid., 1933, 130, 847.31 Sci.Papers Inst. Phys. Chem. Res. Tokyo, 1932, 18, 245; A., 892.32 Nature, 1932, 129, 833; A., 670.33 Proc. Roy. SOC., 1931, [ A ] , 132, 98; A., 1931, 992; Naturwiss., 1931, 17,34 Nature, 1931, 128, 149; A., 1931, 994.35 Thesis, Paris, 1927; Compt. rend., 1926, 182, 460; A., 1926, 331.36 NaturwiPs., 1931, 19, 772; A., 1931, 207.37 Japanese J . Physics, 1931, 7, 33; A., 667; Nature, 1931, 128, 759; A , ,28 Ibid., p. 591; A . , 1931, 666.Ibid., 129, 649 ; A., 554.894; A., 1931, 1348.1931, 1348.K. T. Batinbridge, J . Franklin Inst., 1931, 212, 317; A., 1931, 1207RUSSELL. 305from F. W. Aston’s results is given in the table. The correspondingvalue for boron is calculated from A.Elliott’s 39 abundance ratioBll : BlO, 3-63 & 0.02, for Chilean boron.Despite S. Meyer’s40 advocacy of the value 0l6 = 16.0000 asthe best standard for chemical atomic weights, the InternationalUnion for Chemistry,41 guided largely by F. W. haswisely decided not to depart from the conventional and practicalstandard, 0 = 16, at present in existence, for ,it is very probablethat the abundances of 0l6, OI7, and 0 l 8 in nature is so invariablethat the mean atomic mass of the oxygen atom is as precise aconstant as that of 016. For purposes of atomic and nuclearstructure, radioactivity, mass-spectrography, etc., where a precisionof 1 in 105 is desirable and is expected to be attained, the neutralatom 0l6 = 16.0000 has been chosen from its competitors asstandard by the International Radium-Standards Committee.43The ratio of a mass on this physical standard 0l6 = 16 to that onthe other-the Naud6 correction-has been hitherto taken as1.000125.47 New determinations of this constant have been madeby R.Mecke and W. H. J. Childs 45 and by F. W. A ~ t o n . ~ ~ Theformer find the relative abundances 0l6 : 01’ : 01* as (630 &20) : 0-2 : 1, the latter as 536 : 0-25 : 1. These values raise S. M.Naud6’s correction to approximately 1.0002, an alteration whichcan, of course, have a trifling effect only on the values of atomicweights calculated from mass-spectrograph data, such as are givenin Table 11. The relative abundance W5 : N14, given earlier as1 : 700, has been determined as 1 : 346 by G.M. Murphy and H. C.Urey.48The Neutron.The existence of a neutron, possibly an ultimate particle, ofmass approximately 1 and charge zero, was mooted by J. Chadwick l5as the simplest interpretation of a series of observations initiatedby W. Bothe and H. B e ~ k e r , ~ ~ which were continued and followedup by (Mme.) I. Curie 50 and F. J ~ l i o t , ~ ~ by H. C. Webster,52 and39 Nature, 1930,126,845; A., 1931,15; Z.Physik,1931,67,75; A . , 1931,279.40 Physikal. Z . , 1932, 33, 301; A., 442.41 Ber., 1932, 65, [ A ] , 33; A., 554.43 Phil. Mag., 1931, 12, 609; A., 1931, 1108.44 Ann. Reports, 1930, 27, 310.45 2. Physik, 1931, 68, 362; A., 1931, 543.413 Nature, 1932, 130, 21; A . , 894.4 8 Physical Rev., 1932, [ii], 41, 141 ; A., 980.q9 2.Physik, 1930, 66, 289; A., 1931, 142.50 Compt. rend., 1931, 193, 1412; A., 210.51 Ibid., p. 1415; A., 210; ibid., 1932, 194, 273; A., 210.52 Proc. Roy. Soc., 1932, [ A ] , 136, 428; A., 671.42 Nature, 1931, 128, 731.4 7 Ann. Reports, 1930, 27, 306306 SUB-ATOMIC PHENOMENA AND RADIOACTIVITY.finally by himself. Beryllium under bombardment by a-particles didnot emit protons as did boron or nitrogen, but gave out a weakradiation more penetrating than any y-radiation known. Thiswhen examined by ionisation methods caused material containingcombined hydrogen to emit swift protons. The explanationsuggested for this striking occurrence was that the protons hadgained their energy by a radiation recoil in a process similar tothe Compton effect with electrons; the quantum energy of theradiation was accordingly deduced. J.Chadwick 1 5 9 s3 found thatswift recoil atoms were liberated when the radiation traversed notonly hydrogen-containing material but also helium, lithium, carbon ,air, and argon. His results showed that, if energy and momentumwere conserved in these encounters, the quantum hypothesis ofthe radiation emitted would not hold ; the existence of the neutronwas the simplest explanation of the facts. A neutron in motionwould be expected to produce little if any ionisation in passingthrough matter and to indicate its presence by the recoil of anatomic nucleus with which it collided. Such recoil nuclei wouldbe expected to be easily detected in an ionisation chamber or ina Wilson expansion chamber.The velocity of recoil of a givenatom would be expected to fall off when the radiation was passedthrough increasing thicknesses of an absorbing material such aslead. (This would not be expected if the radiation were a y-radiation.) These expectations have been verified by J. Chadwick.The velocity of the neutron when it is liberated is estimated asone-tenth of that of light. Its mass is found as probably between1-005 and 1.008, suggesting that the neutron may be a small dipolemade up of proton and electron or even a proton embedded in anelectron. Neutrons are found to be emitted by boron as well asfrom beryllium. The processes imagined are Be9 + He4 -+C12 + nf, Bl1 + He4 --+ N14 + nl, d denoting the neutronand the other symbols the nuclei of the elements named.(It isfrom the second expression that J. Chaddck, taking cognizanceof energies and masses, deduced the neutron’s mass.) It is probablethat other processes occur simultaneously, e.g., Be9 + He4 4C13 + y-radiation and B1* + He4 + N1* + y-radiation. N.Feather made an important advance in the work on neutronsby showing that they also could effect artificial disintegration.He obtained disintegration tracks in an expansion chamber re-sulting from collisions of neutrons with nitrogen 54 and with oxygen s5which could be interpreted as n1 + N14 -+ He4 + Bll, the reverseof J. Chadwick’s result, and as nl + 0l6+ C13 + He4. TherePTOC. Roy. XOC., 1932 [ A ] , 138, 692; A., 790.84 Ibid., p. 709; A., 790.6 5 Nature, 1932, 130, 237; A., 081RUSSELL. 307are with nitrogen other possibilities than the ejection of an a-particle : certainly the liberation of a proton, possibly the liber-ation of H2. (Mme.) I. Curie and F. Joliot 56 find that neutronsmay be emitted by lithium, that those emitted by beryllium formtwo groups, and that photons may be emitted simultaneously withneutrons; their results confirm the neutron hypothesis from adifferent angle. Further confirmation comes from the work of3’. Rasetti 57 and of J. L. Destouches.so The excitation of neutronsby radon and their transmission through matter has been studiedhy M. de Broglie and L. Leprin~e-Ringuet,~8 and their penetratingpower by J. Thibaud and F. D. La The existence ofneutrons and of H2 has encouraged theorists to attempt to accom-modate them in the nuclei of light atoms.H. C. Urey’s scheme 61preceded his experimental work.8 Provisional schemes, independentbut in some respects similar, have also been put forward by H. L.Johnston,62 F. Perrin,63 J. H. BartlettYa E. G. Jones,65 W. D.Harkins,66 and others. In one of F. Perrin’s schemes, the “ demi-helion ” is envisaged. This is a particle of mass 2 and charge 1,the union of proton and neutron, and known in the free state asthe heavier isotope of hydrogen. The oldest scheme is due toW. D. Harkins.’Artiscia1 Disintegration by Swift Protons.J. D. Cockcroft and E. T. S. Walton 67 developed the techniqueof producing and using steady high potentials up to 600,000 volts.When lithium oxide was bombarded with a stream of protons, a-particles in pairs were found to be produced.The effect becameappreciable when the protons had been accelerated beyond 120,000volts ; at 250,000voltsadisintegrationparticlewas got for about everylOQ protons striking the lithium. The process imagined is Li7 + H1+ He4 + He4, the symbols representing the nuclei of the elementss6 Nature, 1932, 130, 57; A., 895.6 7 Naturwiss., 1932, 20, 252; A., 556.68 Compt. rend., 1932, 194, 1616; A . , 672; Nature, 1932, 130, 315; A.,b9 Cornpt. rend., ,1932, 194, 1647; A., 672.6o Ibicl., p. 1909; A., 672.131 J . Amer. Chem. SOC., 1931, 53, 2872; A., 1931, 1108; Nature, 1932,130, 403; A., 1074.62 J . Amer. Chem. SOC., 1931, 53, 2866; A., 1931, 1108.us C m p t .rend., 1932, 194, 1343, 2211 ; A., 556, 790.64 Nature, 1932, 130, 166; A., 894.66 Ibid., p. 580; A., 1187.6% J . Amer. Chem. SOC., 1932, 54, 1254; A., 556; Nature, 1933, 131, 23.6 7 Nature, 1932, 129, 649; A., 556; PTOC. Roy. SOC., 1932, [A], 137, 2291073.A., 893; Nature, 1933, 131, 23308 SUB-ATOMIC PHENOMENA AND RADIOACTIVITY.named. A similar disintegration was found to occur less readilywith boron and fluorine, appreciably less with uranium, aluminium,and carbon, and to averyslight extent with a few other elements. Theprocesses here provisionally imagined are Bll + H1 -+ He4 +Be8 or 3He4, F19 + H1 --+ He4 + 0lG, A127 + H1 ---+ He4 +MgZ4, etc., the nature and mass of the residual atom being such thatatomic mass and atomic number are conserved in the process.Itmay be significant that the elements which suffer the emission of theor-particle most easily have masses of form 4a.+3, a being an integer,i.e., have nuclei presumably made up of 3 protons and 2 electrons inaddition to more stable units. It is reasonable to suppose that thecapture of a proton in such nuclei might result in the formation andexpulsion of an a-particle from it. To sum up : Originally, artificialdisintegration of light atoms consisted only in the production ofprotons by swift a-particles. Now a-particles have been shown toproduce neutrons. Each of these processes can also occur in reverse ;protons can produce a-particles, neutrons can produce cc-particles.Neutrons can, in addition, produce protons, but the inverse processhas not yet been demonstrated.Not less in importance is thenature of the resultant residual atom. When the a-particle is theprojectile, the resultant atom is of higher atomic number than thatbombarded; when neutrons or protons bombard, i t is of loweratomic number.Radioactive Constants, Fundamental Constants, and OtherData.A complete survey of radioactive and other atomic constants hasbeen made by the International Radium-Standards Committee.43They give as masses H = 1.0078, proton = 1.0072, He = 4.00216,a-particle = 4.00106, and the electron = 0.000548 (0l6 = 16.0000) ;(on this scale, unity weighs 1.649 x g.) ; Avogadro's constantis given as 6.0644 x 1023 or 6.0265 x 1023 according as c :4.770 x 10-lo or 4-50 x 10-lo, the former being preferred.Thenumber of a-particles expelled per second by 1 g. of radium (freefrom products) is taken as 3.70 x lolo, and the ratio of radium touranium in minerals as 3.4 x In a few cases alternativevalues are given for the half-periods of radioactive products; e.g.,5-0 and 4.9 days for radium-E and 24.5 and 23.8 days for uranium-X,.3.0 x lo5 Years is recommended for uranium-11, the direct measure-ment agreeing with the value deduced from Geiger and Nuttall'srelation. C. H. Collie 68 has, however, since shown, as the result ofthree concordant experiments, that the half-period of this productmust be a t least a million years. He separated electrolytically the68 Proc. Roy. SOC., 1931, [ A ] , 131, 541 ; A., 1931, 891RUSSELL.309uranium-11 arising from the decay of a known quantity of uranium-X and counted the a-particles from the source electrically. 0.Gratias and C. H. Collie 69 found the half-period of uranium- Y to be24.0 & 0-58 hours, the accepted value, 24.6, being ascribed to lackof saturation in the electroscopes used in decay measurements.New determinations of the half-period of uranium-X, and of theactinium-radium branching ratio from uranium by E. Walling 70confirm the International values, the higher alternative in the firstcasc. A. F. Kovarik and N. I. Adams 71 confirm the Internationalvalues for the radium-uranium ratio in minerals and the actinium-radium ratio ; they obtain directly the half-period of uranium-Ias 4.52 x lo9 years, 3% higher than the International value.P.S0ddy,~2 from the growth of radium in uranium purified 25 yearsago, finds the half-period of ionium as 7-41 x lo4 years, 12% lessthan the International value.Great progress has been made in the analysis of groups of a-particles both by the electrical counting methods employed a tCambridge 73 and by the magnetic deviation method used in Paris.73(Lord) Rutherford, F. A. B. Ward, and W. B. Lewis 7* have foundthat the long-range a-particles from radium-C’ may be analysed intonine homogeneous groups of ranges 7-12 cm. The most abundantof these groups has 16.7 particles per million of the ordinary groupof range 6.96 cm., the remainder have abundances varying from 0.2to 1.27 per million.(Lord) Rutherford, C. E. Wynn-Williams, andW. B. Lewis 75 find two groups of long-range particles from thorium-C’, of ranges 9.78 and 11.66 cm., in a ratio 1 : 5.6, the long-rangeparticles having an abundance relative to the ordinary group ofrange 8.62 cm., of 1.9 per million. (S. Rosenblum 73 had foundthem even more complex and since then has extended 76 his result.)The earlier work 73 on the complexity of the particles from actinium-C was confirmed ; actinium47 has two groups in relative abundance0.19 and 1, and relative velocity 0.9737 and 1. The values for thehomogeneous group from actinium-C‘ are on this scale 0.0032 and1.062 respectively. The relative velocities have been confirmed by(Mme.) P. Curie and S. R ~ s e n b l u m , ~ ~ who find 0.973 : 1 : 1.062.W.B. Lewis and C. E. Wynn-Williams 78 have analysed the particlesfrom actinon into two groups, the complexity with this product6s Proc. Roy. Soc., 1932, [A], 135, 299; A., 443.T o 2. Physik, 1932, 75, 425, 432; A., 555.71 Physical Rev., 1932, [ii], 40, 718; A., 790.72 Phil. Mag., 1931, 12, 939; A., 5.74 Proc. Roy. SOC., 1931, [ A ] , 131, 684; A., 1931, 890.j5 Ihid., 133, 351 ; A., 1931, 1349.7 6 Compt. Tend., 1931, 193, 848; A., 5. 7 7 Ibid., p. 33; A., 1931, 995. ’* Proc. Roy. SOC., 1932, [A], 136, 349; A., 671.73 Ann. Reports, 1930, 27, 313310 SUB-ATOMIC PHENOMENA AND RADIOSCTIVITY.being similar to that with actinium-C, with regard t o \Jot11 relativenumbers and relative velocities. As (Mme.) I. Curie 79 had foundthat the a-particles from radioactinium consist of two groups inabout equal numbers, it would appear that there is some recurringcharacteristic of the nucleus underlying this phenomenon.(Mme.P. Curie and S. Rosenblum,so however, have found that radio-actinium is more complex than has been supposed. Its particleshave six or seven groups, two of which are very strong, two strong,and the remainder weak. Actinium-X, however, was found tohave two groups of particles.) S. Rosenblum and (Mlle.) C. Cham% ahave found that radiothorium emits two and possibly three groupsof particles, and S. Rasenblum 82 found two groups from radiumitself. During these investigations, actinium-A , thoron, thorium-A ,radon, and radium-A were found t o give homogeneous particles;many determinations of ranges and energies of a-particles fromevery product except uranium, protoactinium, and thorium havebeen recorded there and elsewhere.83 The accepted values of theranges of uranium-I, thorium, and uranium-I1 have been confirmedby F.N. D. Kurie,B4 G. H. Henderson and J. L. Nickers0n,8~ andS. Bateson 86 respectively.Evidence that the emission of y-rays from radium-C’ is intimatelyconnected with the occurrence of its groups of long-range particleswas given by (Lord) Rutherford, F. B. Ward, and W. B. Lewis; 74it was concluded that the y-rays arise from the transition of ana-particle in an excited nucleus between two levels of differentenergies. This question has been discussed in more detail by (Lord)Rutherford and C.D. Ellis,s7 C. D. Ellis,ss and (Lord) Rutherfordand B. V. BowdexS9 For radium-C’ it is supposed that in thepreceding transformation the emission of an a-particle causes aviolent disturbance in the resulting nucleus which causes some ofthe constituent a-particles to be raised to a much higher level thanthe normal. These, being unstable, are believed to fall back aftera very short interval to normal level, emitting their surplus energyas y-radiation of definite frequency. The ideas of wave mechanics,79 Compt. rend., 1931, 192, 1102; A., 1931, 783.]bid., 1932, 194, 1232 ; A., 555.Ibid., p. 1154; A., 555.82 Ibid., 195, 317; A., 895.83 S. Rosenblum and G. Dupouy, Compt. rend., 1032, 194, 1919;G. H. Briggs, J. Xci. Inst., 1932, 9, 5; Nature, 1932, 130, 1000.84 Physical Rev., 1932, [ii], 41, 701 ; A., 1186.E 5 Ibid., 1930, [ij], 36, 1344; A., 1931, 16.s6 Canadian J.Res., 1931, 5, 567; A., 106.8 7 Proc. Roy. SOC., 1931, [ A ] , 132, 667; A., 1208.88 Ibid., 1932, [A], 136, 396; A., 671. 89 Ibid., p. 407; A., 671.671 RUSSELL. 31 1however, suggest that in this short interval there is a small chancethat some of the a-particles in the higher states can escape from thenucleus. On this view the escaping a-particles are the long-rangeparticles observed, and their energies give the values of the energylevel in the nucleus which they occupied before escape. It was, infact, found that the differences of energies between the variousgroups of a-particles were closely connected with the energies of themost prominent y-rays in the spectrum, and, in general, strongevidence was found that y-rays have their origin in the transitionsof one or more a-particles in an excited nucleus.The energies setfree in transitions are given approximately by the expressionE = pEl-qE,, where El is a difference in energy of two states,Ez a smaller difference of interaction, and p and q integers. Fortyy-rays from radium-C’ and a smaller number from radium-B canbe conveniently expressed by such an equation.The connexion between a-particles and y-rays in thorium-C isdifferent. With radium-C’ the most intense a-particle has the lowestenergy and the long-range particles are rare occurrences ; this is notso with thorium-C. G. Gamow has proposed that here the thorium-C nucleus is initially formed with all the a-particles in the groundstate, not, as with radium-C‘, with some of the a-particles in higherlevels of energy, and that disintegration can sometimes occur insuch a way as to leave the product nucleus excited.found that the y-rays were emitted immediately after the dis-integration of thorium-C, in agreement with G.Gamow’s 9o theory.This provides further proof of the connexion of y-rays with exciteda-particle states in the nucleus. After the discovery that actinonemits two distinct groups of a-particles, it was found by (Lord)Rutherford and B. V. Bowden s9 that the transformation actinon +actinium-A was accompanied by weak @-rays and strong y-rays.From the measurement of the penetrating power of the latter, itwas concluded that the energy of the y-rays is of the right order tobe expected from the difference of energies of the a-particle groups ;again, strong confirmatory evidence that y-rays have their originin transitions of a-particles in an excited nucleus.The controversy as t o the most probable values of the fundamentalconstants, e, h, and the reciprocal of the fine-structure constant,2xe2/hc, continues.W. N. Bond 91 has developed a new way ofreducing the experimental data used in connexion with the determin-ations of e and A which is based on the observa-tion that each group ofO0 Nature, 1930, 126, 397; A., 1339.O1 Proc. Physical Soc., 1932, 44, 374; A., 672; Nature, 1931, 127, 557;A., 1931, 667; Phil.Mag., 1930, 10, 994; A., 1931, 143; ibid., 1931, 12, 632;A., 1931, 1207; Physical Rev., 1932, [ i i ] , 41, 368.C. D. Elli312 SUB-ATOMIC PHENOMENA AND RADIOACTIVITY.experiments connects h and e by an equation of the form h = Aen,where n is 1, 4/3, or 5/3 according to the experiments. He givesto e, h, and hc/2xe2 respectively (significant figures only) the values4.799, 6.558, and 137.02. From the same data, however, R. T.Birge 92 gets 4.769, 6.544, and 137.31. F. Kirchner 93 gets 4-798,6.615, and 137.09 or 4.782, 6.577, and 137.25, depending upon whichalternative data, derived from measurements of the slzort-wavelimit of the X-ray spectrum, are taken. K. Shibag4 has alsocritically reviewed the available data. Me argues that the X-rayvalue of e gives consistent values of h by eight methods.His valuesare e = 4.803, h = 6.624, and hc/2xe2 = 137.03. There is still,therefore, at, the present level of accuracy of measurement, a casefor (Sir) A. S. Eddington's theory,95 which requires for the reciprocalof the fine-structure constant the exact value 137. There appearsto be little, however, for his other theory,gG which requires for theratio of the masses of proton and electron the value 1849.6.Chemistry of Protoactiniurn.A. V. Grosses7 has continued his work98 on the chemistry ofprotoactinium, working with 10-50 mg. of pentoxide free fromother metals. It has been generally assumed that the pentoxidesof tantalum and protoactinium are chemically very similar, as are,for example, the corresponding compounds of barium and radium.They are, however, widely different.Protoactinium is definitelybasic, as it should be from its position in the periodic classification,whereas tantalum is feebly acidic. They are similar in that bothoxides dissolve in 40% hydrofluoric acid and are precipitated byammonia from mineral acid solutions. Protoactinium oxide isinsoluble in molten potassium carbonate (in which tantalum oxideis completely soluble), and almost entirely soluble in molten sodiumbisulphate (in which tantalum is nearly insoluble). Protoactiniumis precipitated from acid solutions by excess of phosphoric acid;there is no corresponcliiig precipitation with tantalum. Theseparabion is, in consequence, a simple matter.0. Gratias 9s hasindependently made similar observations with unweighably smallquantities of protoactinium ; he used an amplifier and an ionisation92 Physical Rev., 1932, [ii], 40, 228; A . , 672.93 Ann. Physik, 1932, [v], 13, 59; A., 556.94 Sci. Papers Inst. Phys. Chern. Res. Tokyo, 1932, 19, 97; A . , 1187.9 5 Ann.. Reports, 1930, 27, 323; A., 1929, 231.9 6 Proc. Camb. Phil. SOC., 1931, 27, 15; A., 1931, 279; Ann. Reports, 1930,O 7 J. Anzer. Chem. Soc., 1930, 52, 1742; A . , 1930, 883.9s Ann. Reports, 2928, 25, 313.99 Thesis, Oxford, 1932; 0. Gratias and C. H. Collie, J., 1932, 987 ; d., 443.27, 324RVSSEU. 313counter to detect the radioactive material’s presence in the chemicaloperations. He showed that the product of decay of uranium-Yemitted a-particles, and had approximately the same half-periodand the same chemical properties as protoactinium.He has thusestablished directly by experiment what hitherto has been merelyassumed on general grounds, namely, that uranium-Y is the directparent of protoactinium.The Penetrating Radiation.The problem of the cosmic or penetrating radiation has definitelyadvanced towards solution during the period under review, althougha t first sight it would appear that opinion about i t could hardly bemore widely divided; its nature has been variously describedas quantum, neutron, electron, and positively charged particle.There has been a gradual change, however, from the older quantumview of R. A. Millikan to the view that the radiation is a very high-energy particle. The former view has been reconsidered by (Sir) J.H.JeansY3 who rejects the view that the radiation can be anythingbut y-radiation on the grounds that a charged particle would bedeflected in the laboratory by a magnetic field, which was apparentlynot the case,4 and could not fall evenly on the earth, as it does,5owing to the influence of the earth’s magnetic field. He has cal-culated the penetrating power of the radiation on the assumptionof R. A. Millikan that part of it is generated by the formation ofnuclei of iron from the necessary protons and electrons, and on hisown assumption, by the annihilation of one proton or four protonsby their respective electrons. In this calculation he has used theformula of 0.Klein and Y. Nishina,6 the scattering electrons beingtaken as all the electrons in the atom and not, as is generally done,the extra-nuclear electrons only. The two hardest constituents ofpenetrating radiation, as found by E. Regener,’ have penetratingpowers very close indeed to the calculated values on the assumptionthat four protons and one proton have been annihilated; thesynthesis of iron gives much too soft a radiation in this calculation.(Sir) J. H. Jeans has pointed out that if the radiation had such anorigin there is no need to assume, as R. A. Millikan has done, thatthe process is still occurring in the depths of space. It may becalculated that the hardest constituent of the radiation is so pene-trating that it woulcl not be reduced to l i e of its initial intensityAnn. Reports, 1930, 27, 322.Nature, 1931, 128, 104; 127, 594; A4., 1931, 666.P. Epstein, €‘roc.h7at. Acad. Xci., 1930, 16, 658.K. Grant, Nature, 1931, 127, 924.Ibid., 1931, 127, 233; A., 1931, 408.Ibid., 1928, 25, 321.ti Ibid., 1928, 122, 395314 SUB-ATOMIC PHENOMENA AND RADIOACTIVITY.until after 5 x 1015 years, a period greater, so far as is known, thanthe age of the universe. The penetrating radiation of to-day maytherefore be the result of the annihilation of matter (possibly nearthe surfaces of astronomical bodies, more probably in unattachedatoms or molecules in free space) a remote period ago. A similarview has been tentatively advanced by E. Regener.*The replacement of the ionisation vessel by the Wilson cloud-chamber and the Geiger-Miiller particle-counter has given resultswhich have modified the above views. The newer workers regardthe radiation as a particle.C. D. Ander~on,~ P. M. S. Blackettand G. Occhialini lo and others l1 have devised apparatus so thatthe penetrating ray itself actuates the Wilson cloud-chamber,and a photograph of what is occurring may be taken a t the timeand not at random. In the device of P. M. S. Blackett and G.Occhialini the cloud-chamber is inserted between two Geiger-Muller counters in line. Passage of the penetrating radiationthrough both counters actuates the cloud-chamber within 0.01 see.,which is sufficient interval to enable the track to be photographed.They found that only about 10% of the tracks were markedly bentin a field of 2000 gauss, so that if the radiation was an electron itsenergy would be 106-107 volts. The remainder, unbent, corre-sponded with electrons of 6 x lo8 volts or protons of 2 x los volts.C.D. Anderson found a much smaller proportion of unbent tracks ;they were quite rare. He observed pairs of tracks frequently, oneof which was always that of an electron. He ascribed these to thedisruption of a single atomic nucleus by the penetrating radiation.Sudden bursts of ionisation, as though from a shower ofionisingparticles from a violently bursting nucleus, have been observed byE. G. Steinke,12 H. Schindler,13 A. H. Compton,14 and others.These appear to be greater than those given by any a-particle andto be more frequent at high altitudes. The radiation also behavespeculiarly when it traverses successively thicknesses of two differentmetals; a peculiar secondary radiation is set up related to theprimary as are 8-rays to or-particles. H. Geiger l5 interprets thispuzzling occurrence by regarding the radiation as protons with veryhigh energy. The older observation that the radiation comes* Nature, 1931, 12'7, 869.lo Nature, 1932, 130, 363.11 L. M. Mott-Smith and G. L. Locher, Physical Rev., 1931, [ii], 38, 1399;1932, 39, 1883; A., 5; T. J. Johnson, W. Fleisher, and J. C. Street, ibid.,1932, 40, 1048.Physical Rev., 1932, [ii], 41, 405.l2 Physikal. Z., 1930, 31, 1019; 2. PIr?y.sik, 1932, 75, 115; A . , 566.l3 Naturwiss., 1932, 20, 491 ; A . , 791.14 Physical Rev., 1932, [ii], 41, 681. l6 Nature, 1931, 127, 785RUSSELL. 315equally from all parts of the sky has been confirmed.16 While,however, V. F. Hess l7 has found that the sun does not contributemore than 0.5% of the total intensity a t 2.5 km. above sea-level,A. H. Compton l8 found that the intensity a t 3-9 km. was 1.5 -40.25% greater between 8 a.m. and 4 p.m. than between the corre-sponding night hours. The same observer,lS in accord with J.Clay 2o but in discord with earlier observation^,^ found that theintensity of the radiation is in general higher the greater the angle ofmagnetic dip.A. S. RUSSELL.l6 E. Regener, Nature, 1932, 130,364; 2. Physik, 1932, 74, 433 ; A., 1072 ;l7 Nature, 1931, 127, 10; A., 1931, 143.ao Proc. K . Akad. Wetensch. Amsterdam, 1930, 7, 711.A. Piccard, Comnpt. rend., 1932, 195, 71.Physical Rev., 1932, [ii], 41, 111. l9 Ibid., p. 681

ISSN:0365-6217    

DOI:10.1039/AR9322900299

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

INDEX OF AUTIIORS' NAMES.ABBOTT, A. C., 285.Abersold, J. N., 236.Achenbach, A., 287.Achmatowicz, O., 204.Acker, W., 257.Aclrermann, D., 244, 243.Ackermann, P., 83.Adam, N. K., 241.Adams, L. H., 278, 270.Adams, N. I., 309.Adams, R., 69.Addoms, R. M., 356, 265.Adkins, H., 100.Adler, E., 216, 217, 218.Ahlfeld, F., 277, 285.Albrecht, W. A., 258.Alder, K., 112, 113, 163, 178.Alderman, A. R., 297.Allen, F. W., 266, 267.Allen, N. P., 79.Allison, F., 74, 300.Allmand, A. J., 50, 51, 52.Alyea, H. N., 45.Amaldi, E., 62.Aminoff, G., 287, 293.Ammann, C., 118.Andersag, H., 214.Andersen, C. C., 131.L4nderson, C. D., 314.Andrew, J. H., 95, 279.Ankersmit, P. J., 160.Antropoff, A. von, 77.Ant-Wuorinen, O., 132.Anwar-Ullah, S., 87.Aoki, Y., 87.Aoyama, K., 279.Applebey, M.P., 94.Archangelskaya, N. A., 296.Archbold, H. K., 26G.Arend, J. P., 292.Arnold, C., 234.Asahina, Y., 192.Aschan, O., 286.Askew, F. A., 253.Assarsson, G., 93.Aston, F. W., 303, 304, 305.Atkins, W. R. G., 234, 295.Atkinson, E. A., 235.Atsumi, K., 186.Atterer, M., 136.Auger, V., 288.Austerweil, G., 81, 293.Austin, P. R., 146.Azzalin, E., 230.Baccaredda, M., 287.Bachmann, W. E., 100, 147.Badami, J. S., 59.Bader, G., 89.Badger, R. M., 62, 63.Badoche, M., 176, 177.Baeckstrom, S., 88.Bar, O., 287.Bar, R., 60.Baerts, J., 117, 137.Baetcke, E., 191.Bailey, C. R., 61, 62.Bain, G. W., 289.Bainbridge, K. T., 302, 303, 304.Bandy, M. C., 294.Bannister, F. A., 286, 289, 293.Barcroft, J., 219.Bardhan, J.C., 152.Bargellini, G., 192.Barger, G., 197, 207.Barker, E. F., 61, 302.Barnes, L. L., 300.Barnes, R. B., 59.Barnes, V. E., 290.Barsha, J., 136.Barth, T. F. W., 277, 282, 289,Bartholomew, R. P., 257.Bartlett, J. H., 307.Bassett, H., 78, 94.Bastien, P., 95.Bateman, A. M., 286.Bateson, S., 310.Bauer, L. H., 277.Bauer, W. H., 52.Baumgartner, H., 219.Baur, E., 94.Baur, H., 93.Bavendamm, W., 287.Bawn, C. E. H., 50, 56.Bayer, O., 169.Beale, C. H., 147.Beaumont, A. B., 256.Becker, C., 55.Becker, E., 89.Becker, G., 88.290.31318 INDEX OF AUTHORS' NAMES.Becker, H., 306.Beckman, A. O., 50.Beliankin, D. S., 277, 289, 292.Bell, D. J., 130.Bell, J., 52.Bell, R.P., 40, 80.Belval, H., 264.Benade, 297.Benedetti-Pichler, A., 233.Bengough, G. D., 89.Senndorf, O., 168.Benrath, A., 93.Benrath, H., 94.Benton, A. F., 79.BBraneck, J., 52.Berchet, G. J., 108.Berek, M., 276.Beretta, U., 50.Berg, G., 277.Berg, H., 217.Berg, R., 231, 232, 233.Bergel, F., 191, 192.Berger, F., 180.Bergmann, E., 74, 102, 111, 167, 185.Berl, E., 297.Berman, H., 290.Bernal, J. D., 240.Bernhauer, K., 115, 272, 273.Berthoud, A., 52.Betechtin, A. G., 284.Beyer, H., 204.Bhagavantam, S., 60, 63.Bicskei, J., 236.Bijl, A,, 78.Bilicke, C., 67.Biltz, W., 88, 278, 284.Binder, J. L., 63.Binet, L., 269.Birch, S. F., 138.Bird, P. G., 293.Birge, R. T., 312.Birk, E., 91.Birkinshaw, J. H., 273, 274.Bischof, W., 90.Bishop, (Miss) E.R., 74, 300, 301.Bito, K., 279.Bjerrum, N., 25, 31.Blacet, F. E., 47, 48.Black, P. T., 269.Blackett, P. M. S., 314.Blake, M. A., 265.Blatt, A. H., 101, 102.Blattny, C., 257.Bleakney, W., 302.Bless, A. A., 282.Blix, R., 294.Bloomfield, G. F., 106, 109.Blount, B. K., 178, 201, 205.Blumendal, H. B., 82, 278.Bodycote, E. W., 131.Bockl, N., 272, 273.Boning, K., 260.Boning-Seubert, E., 260.Bogue, R. H., 94, 278.Bohn, J. L., 283.Boissonnas, C. G., 51.Bolam, F. M., 154.Bolz, F., 133.Bomskov, C., 232.Bond, W. N., 311.Bondi, A., 230.Bone, W. A., 58.Bonhoeffer, H. P., 68.Bonnar, R. U., 295.Booth, H. S., 78, 79, 94.Borchardt, H., 270.Borchert, H., 485.Borgstrom, L.H., 289.Borgstrom, P., 101.Borsche, W., 115.Borst, H. L., 259.Bost, R. W., 237.Bothe, W., 305.Bourdillon, R. B., 253.Bourdouil, C., 265.Bovalini, E., 296.Bovschik, G., 270.Bowden, B. V., 16, 310, 311.Bowden, F. P., 36, 46.Bowden, S. T., 82.Bowen, E. J., 43, 47, 48, 61.Bowen, N. L., 90, 279, 290.Bowley, H., 289.Bowlus, H., 104.Boyd-Barrett, H. S., 199.Brackett, F. P., 47.Bradfield, A. E., 155.Bradfield, R., 292.Bradley, C. A., 61, 63.Bradley, R. S., 42.Bradley, 1%'. M., 78.Brady, 0. L., 230.Briihmer, F., 234.Bragg, W. L., 277.Braida, A., 87.Bramble, W. C., 2G8.Bramley, A., 90.Brammall, A., 281.Brandenberg, W., 207.Brandt, P. L., 82.Brass, P. D., 45.Brauman, P., 82.Braun, J. von, 169.Brauner, B., 81.Braunmiihl, H.v., 61.Brauns, R., 286.Brawley, D. J., 95.Breckenridge, J. G., 69, 181.Breckpot, R., 137.Bredt, J., 156.Bredt-Savelsberg, M., 148, 156.Brendler, W., 289.Bretschneider, H., 201, 208.Bretschneider, O., 87.Brickwedde, F. G., 77, 302.Bridel, M., 265INDEX OF AUTHORS’ NAMES. 319Briggs, G. H., 310.Briggs, H., 297.Briggs, L. H., 203.Briggs, T. R., 78.Bright, H. A., 232.Briscoe, H. V. A., 88, 94.Britton, H. T. S., 85, 220.Brockmann, H., 123.Broderick, T. M., 284.Bronitsky, J., 237.Broom& R., 287.Brown, R. E., 99, 101.Brown, R. R. H., 46.Brown, S. F., 94.Brown, W. G., 49.Brown, W. R., 268.Brownmiller, L. T., 94, 278.Bruch, E., 132.Brussoff, L., 147, 148.Bruggemann, J., 251.Brukl, A., 81, 82, 88.Brunner, R., 94.Brunovski, B.K., 284.Bruylants, P., 117, 137.Bucherer, H. T., 232.Buchkremer, J., 148.Bull, R., 66.Bussem, W., 287.Bumann, I., 131.Bunting, E. N., 94, 278.Briret, R., 176.Burg, A. B., 80.Burrage, L. J., 95.Burrows, H., 247.Burton, H., 175, 200.Bury, C. R., 95, 278.Butenandt, A., 186, 188, 189, 191,240, 241, 242.Butler, C. L., 176.Butler, J. A. V., 34, 79.Buttgenbach, H., 293.Byrd, R. M., 94.Cabannes, J., 60.Caglioti, V., 289, 294.Cagnasso, A., 88, 89.C a b , R. S., 117, 191.Calcott, W. S., 112.Calfee, R. K., 223, 258.Callan, T., 224, 233.Callow, R. K., 274.Calvet, F., 206.Cambi, L., 88, 89.Campbell, A. N., 95.Campbell Smith, W., 281, 298.Canneri, G., 81.Capato, E., 153.Capatos, L., 82.Carothers, W.H., 99, 108, 124, 125.Carpenter, (Sir) H. C. H., 284.Carr6, P., 237.Carrelli, A., 60.Carter, A. S., 112.Carter, G. E. L., 292.Cassie, A. B. D., 61, 62.Caven, R. M., 95.Cazalet, P. V. F., 79.Cernatesco, R., 234.Chadwick, J., 14, 16, 302, 305, 306.Chamik, (Mlle.) C., 310.Charonnat, R., 91.Chassevent, L., 380.Chatterjee, S. K., 289, 291.Chatterji, K. K., 94.Chatwin, J. E., 51.Chauchard, P., 295.Cheesman, G. H., 78.Chen, K., 237.Cheung, W. M., 48.Chibnall, A. C., 272.Childs, W. H. J., 305.Christensen, J. H., 74, 300.Chrzaszcz, T., 272, 273.Chudoba, K., 292.Church, C. G., 267.Cissam, A., 276.Claborn, H. V., 190.Claessens, (Mlle.) J., 234.Clar, E., 163, 164, 166, 168, 170, 286.Clark, E.P., 189, 190. 191.Clark, R. H., 269.Clarke, S. G., 231.Clausen, E., 80.Clay, J., 315.Clemo, G. R., 204.Clough, G. W., 182.Clusius, K., 61.Cockcroft, J. D., 13, 307.Coffman, D. D., 99, 108, 125.Cole, A. G., 170.Cole, R. C., 261.Collie, C. H., 308, 309, 312.Collins, A. M., 108, 124.Collison, R. C., 295.Colmant, P., 137.Colonius, H., 98.Colvin, J., 42.Compton, A. H., 314, 315.Conant, J. B., 101.Constable, J. E. R., 16Cook, C. W., 286.Cook, J. W., 165, 246, 247.Cooke, S. R. B., 287.Cooper, A. J., 87.Cooper, H. P., 255.Cooper, R. A., 231.Copeman, P. R. v.d. R., 266.Corin, F., 276.Cornec, E., 95, 285.Cortese, F., 206.Corti, H., 294.Cosslett, V. E., 82.Costanzo, G., 283.Coulson, A. L., 291.Coulson, E.H., 143320 INDEX OF AUTHORS’ NAMES.Cowan, J. M., 103.Coward, H. F., 54.Cox, E. G., 92, 93, 252, 253.Craggs, H. C., 50.Crew, M. C., 81.Crist, R. H., 52.Crockford, H. D., 95.Crook, A. R., 298.Crozier, R. N., 113.Cunningham, It. N., 244.Curie, (Mme.) I., 14, 305, 307, 310.Curie, (Mme.) P., 309, 310.Dadieu, A,, 61, 66.Dahlmann, H., 88.Daehr, H., 87.Dakin, H. D., 245.Dale, (Sir) H. H., 254.Dalrner, O., 251, 253.Danckwortt, P. W., 227.Dane, E., 239.Daniell, P. J., 55.Danielli, J. I?., 241.Daniels, F., 44, 46, 47, 52.Daniltschenko, P. T., 81.Darbyshire, J. A., 83.Das-Gupta, T., 91.Daubney, C. G., 233.Daujat, J., 102.Davies, C. W., 28.Davies, E. R. H., 95, 278.Davis, C. W., 231.Davis, M.B., 258.Davis, W. B., 267.Dean, P. M., 173.De Broglie, M., 307.Debye, P., 24, 65, 68.De Golyer, E., 285.De Graaff, G. B. R., 160, 161.Dehnert, H., 171.DelBpine, M., 233.De Meuron, G., 195.Deniges, 226.Dennis, L. M., 87.Dennison, D. M., 60, 61, 62, 302.Denny, F. E., 269.De Oliveira, E., 284.Dernies, J., 234.Desai, R. D., 144.Desha, L. J., 228.Destouches, J. L., 307.Deubner, C. G., 268.Deutsch, A., 112.Dewael, A., 117, 137.Dher, N. R., 52, 295.Di Capua, A., 271.Dick, J. B., 230.Dickey, R. M., 287.Dickinson, R. G., 51.Dieke, G. H., 63.Diels, O., 163, 178.Dilaktorsky, N., 277.Dittler, E., 293, 294.Dobbins, J. T., 94.Donath, M., 286.Dornte, R. W., 66.Downing, I?. B., 112.Dragunov, S. S., 84.Drake, L.C., 79.Drake, N. L., 237.Drew, H. D. K., 92, 93.Drudo, P., 31.Drugman, J., 293.Drumm, P. J., 121, 122.Drummond, J. C., 248, 249.Dschang, G. L., 291.Diirr, W., 133.Dusing, J., 88.Dusing, W., 84.Duffin, W. M., 119.Dufraisse, C., 173, 174, 175, 176, 177.Duliere, W. L., ‘200.Dulin, T. G., 256.Dullenkopf, W., 85.Dunn, J. L., 147.Dunn, R. T., 80.Duparqiie, A., 296.Dupouy, G., 310.Duran-Reynals, P., 243.Dyke, W. J. C., 103.Dziengel, I<., 129, 132.Easterfield, T. H., 191.Eastwood, E., 50, 63.Eaton, F. M., 258.Eberius, E., 83.Ebert, L., 22, 66, 292.Eckerson, S. H., 262.Eckert, A., 135.Eddington, (Sir) A. S., 312.Eder, 57.Edisbury, J. R., 240.Egorov, V. S., 04.Ehmann, E. A, YO.Ehmann, H., 152.Ehrenberg, H., 79.Ehret, W.F., 95.Eisenbrand, S., 227, 228.Eitel, W., 276.Elliott, A., 305.Elliott, K. A. C., 69, 181.Ellis, C. D., 310, 311.Ellis, 0. C. de C., 55.Elod, E., 130.Elsen, G., 283.Elmer, H., 131, 135.Emda, H., 180, 185.Emeli?us, H. J., 52, 59.Emery, A., 287.Emich, F., 276.Emschwiller, G., 50.Enderlin, L., 173, 176, 177.Enders, G., 81.Engel, O., 156Ephraim, F., 229,230.Epstein, P., 313.Ernould, L., 117, 137.Ertel, L., 115, 117.Eskola, P., 282.Ettinger, J., 94.Euler, H. von, 268.Evans, C., 94.Evans, J. T., 119.Evering, B. L., 44.Evers, N., 234.Ewald, K. F. A., 91.Ewins, A. J., 197.Eyring, H., 20, 51, 65.INDEX OF AUTHORS' NAMES.Faessler, A., 283.Fahey, 5. J., 291.Fairhall, L. F., 229.Fajans, K., 22.Falkenhagen, H., 28.Farkas, L., 37, 51.Farmer, E.H., 106,119.99, 110, 11Farrington, 0. C., 298.Faull, J. H., jun., 88.Fawcett, R. C., 202.Fedotkev, P. P., 94.Fehkr, F., 88.Feigl, F., 89, 230, 231, 235.Feist, F., 193.Fell, E., 294.Fellner, C., 233.Fenner, C. N., 282, 283.Fermor, L. L., 298.Ferniindez, O., 238.Festraete, G., 117, 137.Ficklen, J. B., 232, 234.Field, (Miss) E., 208.Fieser, L. F., 165, 166, 167, 170.Fill, K., 280.Filson, G. W., 77.Finkelnburg, W., 48, 50, 57.Fiore, 207.Fischer, F., 234, 296.Fischer, F. G., 115, 117.Fischer, H., 287.Fischer, Hans, 209, 211, 212, 213,Fischmann, C. F., 274.Fisher, M. S., 284.Fiszman, K., 84.Fleisher, W., 314.Flenner, A. L., 96.Flood, E.A., 98.Foohey, W. L., 104.Foote, F. J., 222.Foote, H. W., 78.Forbes, G. S., 47, 51.Forjaz, P., 283.Forli-Forti, G., 192.Foshag, W. F., 294.Fothergill, R. E., 99, 10%214, 215, 216, 217, 218, 219.REP.-VOL. xXTX.321Fourneau, E., 207.Fowler, A., 58, 59.Fowler, F. L., 269.Franck, J., 49.Frank, B., 160, 161.Frankenburger, W., 58.Franz, K., 49, 63, 77.Frattini, B., 241.Frauenhof, H., 77.Fred, E. B., 274.Fredholm, H., 232.Freh, W., 289.Freise, F. W., 284, 285.Freudenberg, K., 64, 131, 132, 133,134, 182.Freudenberger, H., 128, 130.Frey, A., 271.Friauf, 5. B., 55.Fricke, R., 83.Fridenson, A., 242.Friedrich, G., 182.Friedrich, K., 131.Friend, S. A. N., 94.Friend, N. A. C., 86.Fries, K., 164.Fromme, J., 291.Furman, N.H., 234.Furuya, M., 26 1.Gajewski, H., GO, 61.Gallay, W., 113.Galley, R. A. E., 110.Gamow, G., 40, 311.Gapochko, M. P., 262.Gardner, J. H., 101.Garner, W. E., 56.Garrick, F. J., 95.Uarstang, W. L., 58.Gassner, G., 257, 2fiY.Gatty, O., 30.Grtubert, P., 293.Gedye, G. R., 50.Gehlen, H., 84.Geib, K. H., 50, '77.Geiger, H., 314.Geilmann, W., 284.Gerhard, S. L., 62.Ghiron, D., 287.Gibson, D. T., 146.Gibson, G. E., 49.Gibson, R. C., 300.Gidvani, B. S., 141Giese, H., 86.Gillam, A. E., 249.Gilman, H., 78, 98, 99, 100, 101, 103,Ginsberg, H., 83.Girard, A., 242.Glass, H. M., 94.Gleditsch, (Mlle.) E., 283.Gleu, K., 86.Go, Y., 231.145, 146.322 INDEX OF AUTHORS’ NAMES.Goebel, H., 240.Goerg, A,, 193.Goeze, G., 257.Goldberg, M.W., 139, 161.Goldschmidt, V. M., 277.Goldsztaub, S., 286.Gonzer, F. A., 291, 298.Goossens, A., 291.Goranson, R. W., 379, 282.Gordon, S. G., 298.GOSS, F. R., 143.Gossner, B., 290, 294.Gothan, W., 297.Gough, G. A. C., 208.Goulston, D., 295.Grace, N. S., 302.Granger, A., 233.Grant, K., 313, 314.Grant, R. L., 251.Grantham, D. R., 295.Grassniann, W., 270.Gratias, O., 309, 312.Greenberg, D. M., 231’.Greenwood, G., 290.Grendel, F., 234.Grieb, C. M. W., 91.Griffiths, S. A. G., 51.Grime, G., 95.Grinten, W. van der, 60.Groll, H. P. A., 98.Gronwall, T. H., 24.Grosse, A. von, 312.Grout, F. F., 280.Groves, L. G., 226.Grundmann, C., 122.Gruner, E., 81, 293.Gruner, J.W., 294.GuBnault, E. M., 54.Guichard, 86.Guilbert, R. E., 25s.Guilliermond, A., 267.Gulland, S. M., 91.Gunning, H. C., 285.Gurney, R. W., 34.Gutbier, A., 231.Guthrie, J. D., 2C9.€3HHHHHHHHHHHHHHaase, L. W., 233.aase, T., 47.aber, F., 45, 4G, 51, 53, 5s.ackspill, L., 80.addock, L. A., 234.adman, G., 45, 46.agenbuch, W. E., 128.ahn, B., 82.ahn, F. L., 220, 232.ahn, G., 207, 208.aitinger, M., 227.aken, H. L., 91.alban, H. von, 23.albig, P., 218.all, D. A., 5 6 .Hall, D. G., 52.Hall, R. E., 278.Haller, H. L., 187, 188, 190.Hallimond, A. F., 278.Hamacher, H., 95.Hamilton, R. T., 79.Hammerschmid, H., 30.Hann, R. M., 237.Hansen, K. W. F., 157, 158.Hara, R., 295.Haraguchi, K., 289.Harder, A., 78.Hardy, S. D., 302.Harker, A, 281.Harkins, W.D., 307.Harris, I. W. H., 75, 97.Harris, L. S., 253.Harris, S. A,, 145.Harrison, L. M., 228.Harry, R. G., 234.Harteck, P., 47, 50, 77.Hartel, H. von, 43, 56.Hartman, R. J., 287.Hartshorn, R., 267.Hartwell, F. S., 54.Harvey, F. E., 56.Harwood, H. F., 281, 292.Haslewood, G. A. D., 240, 241,Hassel, O., 72.Hata, S., 289.Hatt, H. H., 147.Hausmann, W., 21 1.Hawkes, L., 292.Haworth, R. D., 152, 160, 101.Haworth, W. N., 127, 128, 131, 132,Hayes, A. O . , 287.Hedfeld, I<., 61, 62.Heidorn, F., 285.Heidt, L. J., 46, 47, 51, 52.Heilbron, I. M., 248, 249, 280.Hein, F., 86, 225.Heinrich, F., 82.Heisenberg, W., 14.Henderson, E. Y., 293.Henderson, G .H., 310.Henderson, 5. A. R., 233.Hendricks, S. B., 67, 293.Hengler, E., 93.Henne, A. L., 123, 125.Henry, J., 280.Henseleit, K., 244.Hering, H., 94.Heritsch, H., 291.Herrick, H. T., 273.Hertel, E., 50.Hertz, G., 303.Herzberg, G., 39, 47, 49, 61, 63.Herzenberg, R., 285.Heslop, R. N., 248.Hess, F. L., 285, 291, 293.Hess, K., 129, 132, 134, 135.242.252INDEX OF AUTHORS’ NAMES. 323Hew, R., 216, 219.Hess, V. F., 315.Hester, W. F., 102.Heukeshoven, W., 82.Hevesy, G. von, 283, 299.Hey, M. H., 286, 289, 292, 293, 294,Hibbert, H., 136.Hieber, W., 89, 90.Hieger, I., 246.Higashi, K., 295.Higginbotham, L., 113.Hildebrandt, F., 342.Hilditch, T. P., 110.Hilgetag, G., 189, 191.Hill, A. E., 94.Hill, R., 215.Hilzheimer, E., 85.Hinkel, L.E., 80.Hinsberg, O., 166.Hinshelwood, C. N., 43, 43, 46, 53,Hinton, H. D., 104.Hirsch, E., 81.Hirsch, P., 251, 252.Hirst, E. L., 127, 131, 132, 252, 253.Hoag, L. E., 235.Hoar, T. P., 86.Hobbie, R., 283.Hocart, R., 80.Hock, H., 89.Hodgdon, F. B., 292.Holscher, F., 306.Honigschmid, O., 303.Hoffor,M., 115, 118. 119, 122.Hoffman, E., 273, 297.Hoffman, J. I., 221.Hoffman, R. D., 286.Hoffman, R. H., 47.Hoffmann, S., 286.Hoffmann, M. K., 283.Hogness, T. R., 62.Holden, H. F., 215.Holder, G., 83.Holley, K. T., 256.Holmes, A., 280, 281, 283.Holzman, M. F., 181.Hoogstraten, C. W. van, 237.Hootman, J. A., 283.Hopff, H., 132, 133.Hopkins, S. J., 272.Horn, E., 66.Horrobin, S., 224.Horst, (Miss) H.van der, 78.Horwood, H. C., 281.Hose, C., 106.Hoshino, T., 198.Hosking, J. R., 161, 162.Houben, J., 149, 161.Hough, W. A., 232.Howes, W., 287.Howitt, J., 79.Hsueh, C. M., 181.298.55, 58.Hueber, H., 276, 289, 293.Huckel, E., 20, 24.Huniger, M., 84.Huttenhain, J. M., 284.Huttig, G. F., 82.Huf, E., 82.Hugh, W. E., 139.Hughes, G. K., 127.Hulubei, H., 61.Hume, J., 42.Hummel, K., 288.Hummitzsch, W., ‘30.Hund, B’., 20.Hunt, €I., 82.Hupfer, €I., 270.Husemann, E., 78.Huyser, H. W., 159.Ichiinura, T., 290.Iimori, S., 289.Iitaka, I., 87.Ilinski, M., 235.Ima,mura, Y., 261.Ingold, C. K., 136, 1-13, 165, 176.Innes, J. R. M., 253.Irvin, N. M., 79.Irvine, (Sir) J. C., 12‘3, 130.Tshikawa, S., 115.Ishikawa, T., 186.Ittmann, G.P., 60.Tvanov, D., 103.Ivanov, N. N., 262.Ivanov, S., 262.Ives, D. G., 230.Iyer, L. A. N., 281.Jacldsch, J., 252.Jackson, R. F., 238.Jacobi, H., 80.Jacobs, W. A., 197.Janecke, E., 93, 94, 95.Jakob, J., 291.Jakbb, W. F., 86.James, R. W., 60.Jamieson, G. S., 237.Jandebeur, W., 120.Jander, G., 82, 225.Jander, W., 76, 277.Janitzki, J., 86.Janot, M. M., 163.Janssen, G., 257.Jantsch, G., 82.Jawurek, H., 82.Jeanmaire, A., 83, 85.Jeans, (Sir) J. H., 313.Jefferson, M. E., 293.Jenny, H., 268.Jette, E., 236.Jmoudsky, G., 117.Johannsen, A,, 282.John, F., 163, 164324 INDEX OF AUTHORS' NAMES.John, T., 82.Johnson, C. H., 56.Johnson, G. O., 100.Johnson, J.R., 146.Johnson, T. J., 314.Johnson, W. C., 81.Johnston, H. L., 307.Johnston, W. R., 44.Johnstone, H. I?., 236.Joliot, I?., 14, 305, 307.Jones, B., 231.Jones, E. C., 110.Jones, E. G., 304, 307.Jones, G. W., 55.Jones, 1%. H., 91.*Jones, W. H., 99.Jones, W. *J., 103..Jest,, I<., 277.Judefind, W. L.. 237.J~~govirs, I,., 28%.J w ~ , El., 291, 292, 593.Jung, W., 84.,Jurasky, K. A., 297.Just, F., 205.Kastner, F., 293.Kahanowicz, M., 285.Kahn, J., 181.Kalantarian, P., 287.Kallmann, H., 77, 302.Kamm, H., 91.Kandiah, A., 137.Kantor, M., 82.Rapulitzas, H. J., 231.Karantassis, T., 82.Kariyone, T., 186, 188.Karl, A., 289.Karrer, P., 118, 121, 122, 195, 248,Katz, J. R., 135.Katz, M., 111.Katzenstein, (Mlle.) M., 234.Katznelson, R.S., 273.Kaufmann, H., S9,90.Kausch, O., 284.Keesom, W. H., 78.Keinert, M., 03, 94.Keller, H., 206.Kelmy, M., 87.Kennaway, E. L., 248.Kennedy, T. R., 79.Kenner, J., 183.Kern, R., 63.Kerr, P. F., 286, 292.Kharasch, M. S., 96.Kidd, D. F., 294.Kiessling, L. E., 271.Kilpatrick, hl. L., 52.Kimball, G. E., 51.Kimura, W., 237.King, C. G., 251, 253.King, C. V., 236.249.King, F. E., 199.King, H., 183, 208, 239.King, H. J. S., 91.King, H. M., 295.Kinnersley, H. W., 250, 251.Kinoshita, K., 273.Kirby, J. E., 124, 146.Kirchberg, H., 297.Kirchner, F., 312.Kirkbride, F. W., 48.Kirnnenn, A., 145.Kirstahler, A., 211, 214.Kistiakowsky, G. B., 47, 50, 59, 63.Kitschkin, A., 148.Klarding, J., 288.Iilager, K., 191.Klages, B'., 131, 132, 134, 135.Kleiderer, E.C., 69.Klein, G., 263.Klein, O., 3 1 3 .Klein, S., 276.Klemotsen, S., 283.lilemm, W., 80.Klever, E., 292.Kling, A., 234.Klingelhofer, W. C., 50.Kluber, H. von, 277.Klumb, H., 47.Knorre, G. von, 235.Knowles, F., 258.Knowles, H. B., 230, 232.Koch, A., 125.Koch, H., 297.Koberich, F., 287.Koechlin, R., 294.Kohler, E., 288.Koenig, P. M., 230.Kaster, W., 94, 95.Kmveringe, A. J. van, 304.Koga, Y., 244.Kohler, E. P., 102.Kohlrausch, K. W. F., 60, 61, BG.Kohman, E. H., 267.Kolthoff, I. M., 232.Komatsu, S., 263.Kometiani, P. A., 237.Kon, G. A. R., 136, 138, 139, 140,143, 144, 152.Konarzewski, J., 90, 2'80.Kondo, S., 188.Kondrat(tev, V., 49, 58, 59.Koolhaas, D.R., 152, 153, 154, 158.Kordes, E., 292.Kornfeld, (FA) G., 49.Kosaka, H., 267.Kouriatchy, N., 286.Kovarik, A., F., 309.Kovatsch, D., 94.Kozik, S., 291.Kracek, F. C., 95, 279.Krakau, K. A., 95.Kramera, H. A., 63.Krassa, P., 296INDEX OF AUTHORS' NAMES. 325Kratschmai, W., 276.Kraus, C. A., 98.Kraus, E. J., 230.Kraus, H. A., 60.Krause, E., 105.Krauss, F., 88, 92.Kraybill, H. R., 264.Krebs, H. A,, 244.Kreitmair, H., 207.Krestinski, V., 114.Krings, W., 90.Ki%, A., 95.Kriihnke, F., 202.Krombach, H., 95, 285.Krueger, G. von, 85.-11, F., 88.Krumholz, P., 89.Krumpel, O., 211.Kubina, H., 231, 236.Kuster, W., 213, 216.Kuhl, J., 292.Kuhn, H., 19.Kuhn, R., 112, 115,121, 122, 123, 249.Kuhn, W., 133, 134.Kunitz, W., 267, 290.Kupzis, J., 295.Kurie, F.N. D., 310.Kurnakov, N. S., 285.Kursanov, D., 148.Kuposanov, A. L., 266.Kurtenacker, A., 236.Kustenmacher, H., 233.Kuzniar, C., 294.18, 119, 120,Lacroix, A., 297.La Forge, F. B., 187, 188, 189, 190.Laland, P., 251.La Mer, V. K., 24.Lane, C. E., 52.Lange, B., 276.Lange, E., 22, 25, 30, 33.Lange, W., 84, 85.Langenbeck, W., 215.Langseth, A., 60, 61, 62, 63.Langvad, T., 237.Lapworth, A., 20, 115.Laquer, F., 250.Larola, B. D., 119.Larsen, E. S., 288, 290.Lasarev, W., 77, 302.Lasky, S. G., 279, 286.Laasieur, A,, 234.La Tour, F. D., 307.Laubengayer, A. W., 82.Lavrov, F. A., 54.Lavrova, M. N., 262.Lawrenz, M., 74.Laybourn, K., 83, 94, 95.Le Blanc, M., 83.Lederer, E., 249.Lee, A.R., 89.Leermakers, J. A., 51.Lehmann, E., 282.Lehmann, G., 178.Lehrer, G. A., 88.Leighton, P. A., 47, 48.Leighton, W. G., 47.Leishman, (Miss) M. A., 94.Leith, C. K., 287.Leithe, W., 182, 183.Lemberg, R., 219.L e h , A., 194, 267.Leprince-Ringuet, L., 307.Letch, R. A., 117, 137.Leton, E., 138.Letsky, B. M., 152.Leuchs, H., 201, 202, 203, 204.Leutert, F., 89.Levi, A. A., 147.Levi, G. R., 287.Levine, A. A., 170.LBvy, J., 147.Levy, P., 159.Lewis, B., 54, 55.Lewis, W. B., 309, 310.Liang, P., 237.Liberi, G., 288.Libermann, D., 237.Liempt, J. A. M. van, 87.Lieske, R., 296.Lietz, J., 293.Lifschitz, D., 135.Liguori, M., 153.Lillig, R., 207.Lind, S.C., 52, 297.Lindemann, F. A., 14.Lindgren, G. W., 285.Linhard, M., 235.Linser, H., 263.Linsert, O., 253.Linstead, R. P., 108, 117, 136, 137,Lipp, P., 150.Livingston, R., 52.Locher, G. L., 314.Lochte-Holtgreven, W., 50, 63.Loffler, K., 182.Lowenberg, K., 115, 117.Logan, 5. C., 264.Lombardi, L., 166.London, F., 40.Loomis, A. L., 55, 59.Lord, H. D., 90.Losana, L., 95.Loury, M., 175.Lowry, T. M., 31.Luck, K. V., 232.Ludlam, E. B., 45,46.Lueg, P., 61, 62.Luttringhaus, A., 253.Luis, (Miss) E. M., 147.Lukaa, J., 235.Lumsden, J . S., 107.Lund, E. J'., 269.138.L 326 INDEX OF AUTHORS’ NAMES.Lund, H., 237.Lundell, G. E. F., 232.Lundstrom, F. O., 78.Luther, R., 51.Lyons, E., 237.Lyons, H. A.M., 79.Maass, H., 129.Macalpine, G. B., 94.Macbeth, A. K., 127.McCann, D. C., 249.McCartney, W., 188.McClean, D., 243.McCrosky, C. R., 94.McGhee, 5. L., 74.MacGregor, A. G., 292.McHargue, J. S., 223, 258.Machatschki, F., 277, 288.Machemer, H., 127, 132.Mack, E., 67.Mackay, M. A., 232.McKenzie, A., 147.McKie, P., 263.Mackinney, G., 52.MacKinnon, J., 103.Maclennan, G. W. G., 138.McLennan, J. C., 17, 77, 228.McNair, J. B., 261.Macrae, T. F., 91.Maddocks, W. R., 95, 279.Madgin, W. M., 83, 94, 95.Mahlmann, K., 92.Magrou, J., 269.Mahanti, P. C., 61.Maino, M., 241.Mair, J. A,, 124.Malachowski, I. R., 141.Malinovski, A. E., 54.Mallen, (Miss) C. A., 238.Malossi, L., 93, 280.Manchot, W., 88,91.Mann, F.G., 91.Manoev, D. P., 285.Manskaja, S., 268.Manteuffel, R., 115.Marble, A., 254.Mark, H., 132, 133.Marks, H. P., 254.Marrian, G. I?., 240, 241, 242.Marshall, C. E., 292.Marshall, P. G., 165.Marsson, V., 233.Martens, J. H., 276.Martin, F. M., 293.Martin, J. H., 74.Martin, P. E., 61.Marvel, C. S., 181.Marx, H., 234.Marzin, A., 135.Masgill, W., 278.Mason, H. M., 236.Mathers, F. C., 235.Matsui, M., 279.Matthes, H., 232.Matthews, J. A., 238.Maurer, E., 90.Mavin, C. R., 152.Mavrodin, A., 103.May, 0. E., 273.Mayer, F. K., 287, 292.Mayneord, W. V., 246.Mayr, C., 235.Mecke, R., 39, 47, 60, 62, 305.Meer, N., 43, 44, 56.Meier, F. W., 232.Meinel, K., 129.Meisel, K., 88.Meissner, W., 77.Meixner, H., 288, 291.Meixner, J., 25.Melaven, R.M., 67.Mellanby, J., 243.Melsen, J. A. van, 157.Melville, H. W., 45, 46, 50.Menahem, M., 79.Mendlik, F., 207, 208.Menon, K. N., 201.Mensching, J. E., 295.Mentzel, C., 234.Menzel, W., 87.Menzies, R. C., 178.Merritt, P. L., 291.BTerwin, H. E., 279, 283.Merz, A. R., 78.Meulen, J. H. van der, 236.Meyer, H. J., 232.Meyer, H. K., 171.Meyer, J., 159.Meyer, Julius, 85.Meyer, K. H., 132, 133, 173.Meyer, S., 305.Mezzadroli, G., 52.Michalewicz, C., 86.Midgley, T., jun., 123, 125.Miekeley, A., 134.Miller, L. P., 269.Millikan, R. A., 313.Mills, W. H., 64, 69, 181.Minetti, H., 137.Minne, P., 83.Miropolski, L. M., 288.Miyajima, S., 187, 188, 189.Miyazaki, K., 94.Moller, E. F., 122.Moelwyn-Hughes, E.A., 43.Mohammad, S. S., 52.Moll, T., 251, 253.Montagne, (Mlle.) M., 103.Montemartini, C., 83.Moore, H. B., 296.Moore, T., 249.Moorhead, J. G., 63.Morand, M., 304.Moreau, L., 261.Morey, G., 51INDEX OF AUTHORS’ NAMES. 327Morey, G. W., 95, 278, 279.Morf, R., 118, 248, 249.Morgan, G. T., 104.Morgan, W. T. J., 243.Morley, J. F., 86.Morris, H. S., 258.Morris, V. H., 260.Morris, W. C., 78.Morsch, K., 107.Morse, P. M., 62.Morton, D. S., 82.Morton, R. A., 248, 249, 250.Moser, F. H., 147.Moses, C. G., 237.Mosley, K. M., 293.Mothes, K., 263.Mott-Smith, L. M., 314.Mounce, F. C., 256.Moureu, C., 173, 174, 176.Moyer, W. W., 69.MUCCO, J., 255.Mugge, O., 286.Muhlbauer, F., 89, 90.Miiller, E.L., 93.Miiller, H., 276.Miiller, H. J., 160.Muench, 0. B., 283.Muir, J. J., 46.Mulay, A. S., 264.Muller, R. H., 226.Murakawa, K., 304.Murneek, A. E., 264.Murphy, E. J., 74, 300.Murphy, G. M., 77, 302, 305.Murray, D. G., 298.Mussgnug, F., 290.Myles, J. R., 147.Nacken, R., 280.Nzshagen, E., 72.Nagai, K., 186.Nagai, S., 79, 278.Nakamura, G., 304.Nakamura, I., 95.Nakamura, K., 295.Nakaseko, R., 230.Nekashima, T., 134.Nametkin, S., 147, 148.Nanji, H. R., 141, 143, 144.Narliker, V. V., 74.Natta, G., 278, 287.Nernst, W., 27, 33.Newhouse, W. H., 286.Newton, R., 268.Nickerson, J. L., 310.Nieland, EL., 282.Nielsen, H. H., 63.Nielsen, J. R., 61.Niessner, M., 232.Niethammer, A., 268.Nieuwenberg, C.J. van, 82, 278.Nieuwland, J. A., 104, 112.Niggli, P., 282.Nightingale, G. T., 258, 265.Nikitina, E. A., 87.Niklas, H., 270, 271.Nininger, H. H., 298.Nishikawa, T., 181:Nishina, Y., 313.Nishio, K., 284.Nobbe, P., 105.Nockolds, S. R., 281.Noll, W., 277, 280, 292.Noller, C. R., 102, 237.Norris, W. S. G. P., 138.Norrish, R. G. W., 48, 50, 51.Norton, F. H., 292.Norton, R. D., 237.Noyes, W. A., 52.Nuccorini, R., 266.Niissler, L., 211, 215.Nyns, L., 237.Oates, F., 298.O’Brien, J. R., 250, 251.Occhialini, G., 314.Occleshaw, V. J., 95.Odake, S., 244.O’Daniel, H., 290.Oeffner, H., 273.Oertel, G., 205, 206.Ohlmeyer, P., 134.Okuno, T., 94.Olcott, H. S., 249.O’Leary, W. J., 287.Olson, A. R., 63.Ono, M., 187, 188, 189.Onsager, L., 28.Oppenheimer, F., 46, 47.Orcel, J., 287, 291, 294.Orelkin, B.P., 230.Orlov, A., 291, 293.Ortner, G., 81.Osborne, F. F., 281.Oserkowsky, J‘., 261.Osokoreva, N. A., 285.Otake, S., 250.Ott, E., 251.Owe, A. W., 251.Owen, L., 285.Packendorff, K., 251.Pahl, M., 299.Palache, C., 277, 288, 291, 298.Palmer, A. D., 183.Papafil, M., 234.Papenfus, E. B., 284.Papish, J., 235, 277, 287, 300.Parker, A. E., 303.Parry, J., 289.Parsons, A. L., 290.Parsons, G. S., 147.Parsons, J. B., 81328 INDEXPartridge, H. M., 226.Pascal, P., 83, 84.Passerini, L., 87.Patterson, E. S., 78.Patty, J. R., 63.Paul, (Miss) B., 50.Pauling, H., 225.Pauling, L., 17, 18, 75, 91.Pavlovitsch, S., 287, 291.Payman, W., 55.Pearson, T.G., 82.Pelzer, H., 40.Pember, F. R., 258.Penfold, A. R., 117, 155.Penseler, W. H. A., 296.Pentchev, N. P., 296.Percival, E. G. V., 127.Perkin, W. H., jun., 202, 204.Pernot, (Mlle.) M., 95.Perrin, F., 307.Perrott, G. St. J., 55.Perssianzeva, N., 114.Pestov, N. E., 225.Peters, M. A., 167.Peters, R. A., 250, 251.Peterson, W. H., 274.Petrossian, A., 287.Petrov, A. D., 234.Pettinger, N. A., 261.Petzold, W., 94.Pfankuch, E., 149, 151.Pfau, A., 155.PfeifFer, M., 159.Pflaum, D. J., 223.Phillips, F. C., 291.Piccard, A., 315.Pickett, T. A., 256.Picon, 295.Pierce, W. C., 51.Pieth, P., 157.Piggot, C. S., 283.Pica de Rubies, S., 285.Pinkard, F. W., 92, 93.Pinkus, A., 234.Pirani, R., 87.Pirschle, K., 256.Placzek, G., 23, 60, 62.Plake, E., 28.Plant, (Miss) M.M. T., 127.Platenius, H., 264.Plaut, H., 87.Plichta, J., 231.Plyler, E. K., 61.Pobocil, F., 95.Poethke, W., 224.Pogodin, S. A., 95.Pohland, E., 80.Poitevin, E., 288.Polak, L., 49.Polanyi, M., 43, 44, 55, 66.Politis, J. C., 268.Polonovski, Max, 197.Polonovski, Michel, 197.OF AUTHORS' NAMES.Pomeranz, C., 191.Pongratz, A., 66.Pope, M. N., 268.Pope, (Sir) W. J., 180.Porter, C. W., 147.Portevin, A., 95.Poschenrieder, H., 270, 271.Posnjak, E., 277, 279, 287, 290.Poulenc-Ferrand, (Mme.), 288.Powell, S. G., 237.Powers, H. A., 282.Preston, G. H., 92.Prdvost, C., 102, 103.Pringsheim, H., 134, 135, 270.Prochovnick, V., 135.Prodan, L., 229.Pruess, L.M., 274.Prutton, C. F., 95.Pryde, J., 252.Pummerer, R., 125.Purdo, J. H., 256.Pushin, N. A., 94.Quastel, J. H., 246.Qudrat-i-Khuda, M., 152.Quilico, A., 271.Qureshi, M., 62.Qviller, B., 283.Rabe, P., 183, 185.Rabinovitsch, E., 52.Riidulescu, D., 121, 170.Rafalowski, S., 61, 228.Rahlfs, E., 93, 95.Rahman, M. K., 52.Raistrick, H., 273.Rakestraw, N. W., 295.Rakovski, A. V., 87.Ram, A., 62, 295.Raman, (Sir) C. V., 60.Rambaud, R., 145.Ramdohr, P., 276.Randall, H. M., 69, 61.Raper, H. S., 200.RBscanu, R., 87.Rasetti, F., 307.Rath, P., 82, 83.Rather, J. B., 237.Ray, N. N., 79.Ray, P. R., 83.Ray, R. C., 94.Rea, J. L., 248, 249.Read, H. H., 286.RBchid, (Mme.), 84.Redmond, J. C., 232.Regener, E., 313, 314, 315.Reichstein, T., 116, 118, 193.Reid, D.M., 296.Reid, E. E., 237.Reid, J. A., 45.Reif, W., 230INDEX OF AUTHORS’ NAMES. 329Reiff, F., 90.Reinders, W., 87.Iteissttns, G. G., 85.Renoll, M. W., 123.Restaino, S., 93.Reuning, E., 284.Reynolds, R. J. W., 252, 253.Ribaud, G., 55.Ricci, J. E., 94.Rice, F. O., 44, 52.Rice, M. R., 93.Richard, G., 103.Richards, F. J., 257.Richards, T. W., 278.Richards, W. T., 45.Richardson, A. E. V., 257.Richtmyer, N. K., 102.Richtmyer, N. W., 131.Rideal, E. K., 50, 53, 55, 56.Ridgway, L. R., 195.Ries, K., 89.Riesenfeld, E. H., 86.Riley, H. L., 86, 230.Ritchie, A., 46.Ritchie, M., 50.Riza, S., 185.Robbins, W. A., 256.Roberts, E. J., 282.Roberts, H.S., 279.Robertson, A., 187, 188, 193.Robin, J., 174.Robinson, A. L., 30, 33.Robinson, (Mrs.) A. M., 196.Robinson, (Mrs.) G. M., 107, 267.Robinson, P. L., 82, 85, 88, 94.Robinson, R., 20, 96, 105, 107, 178,180, 194, 195, 196, 198, 199, 200,201, 202, 203, 204, 205, 267.Robinson, R. A., 85.Robitschek, J., 233.Rochow, E. G., 87.Rodebush, W. H., 50.Rodolico, F., 290.Roehrich, E., 89.Roffey, F., 56.Roger, C. H., 260, 261.Rogers, A. F., 289, 294.Rogerson, H., 193.Rollefson, G. K., 51.Romer, 281.Rose, H., 217, 291.Rosen, N., 62.Rosenblum, S., 309, 310.Rosenheim, A., 85, 87, 89, 95.Rosenheim, O., 239.Rosenholz, J. L., 276.ROSS, C, S., 286.Rossnovskaja, A. N., 84.Roth, H., 118.Roth, W. A., 88, 280.Rousset, A., 60.Rudge, A.J., 88.Riiffer, E., 265.Ruff, O., 87.Ruhkopf, H., 250.Ruhland, W., 256, 265.Rushton, E. R., 85.Russell, A. S., 79.Rutgers, I. J. J., 242.Rutherford, (Lord), 16, 309, 310,Rutherford, R. L., 294.Ruzicka, L., 148, 152, 153, 154, 157,Rygh, A., 251.Rygh, O., 251.311.158, 159, 160, 161, 162.Saenger, H., 93.Saha, H., 83.Sallentien, H., 134.Salmon-Legagneur, F., 151.Salomon, H., 118.Salomon-Calvi, W., 283.Sandell, E. B., 232.Sanderson, (Miss) I., 78, 94.Sandulesco, G., 242.Sandved, K., 24.Sanfourche, A., 280.Sarkar, P. B., 91.SatB, T., 95.Sattler, H., 56.Sauerwald, F., 90.Sayce, L. A., 94.Sayre, J. D., 260.Sborgi, U., 94, 280.Scatchard, G., 30.Schackmann, H., 90.Schade, W., 112.Schadler, J., 294.Schaefer, C., 63.Schairer, J.F., 90, 279.Schaller, W. T., 288, 293, 294.Schantl, E., 295.Schardinger, F., 134.Schaflenberg, G., 276.Scharizer, R., 294.Schay, G., 55, 56.Scheibe, E. A., 287.Schenck, H., 93.Schenck, R., 85.Scheuer, Z., 272.Schidei, T., 304.Schiflett, C. H., 52.Schilina, M., 268.Schilling, K., 164.Schindler, H., 314.Schleflan, L., 94.Schleier, M., 235.Schlenk, W., 99, 167.Schlenk, W., jun., 99, 100, 101.Schlesinger, H. I., 80.Schlesinger, M., 148.Schlosser, C., 191.Schlossmacher, K., 286.Schlubach, H. H., 131, 135330 INDEX OF AUTHORS’ NAMES.Schmid, H., 88, 91.Schmidt, A., 297.Schmidt, E., 129, 136.Schmidt, (Frl.) E., 89.Schmidt, W., 235.Schnegg, H., 136.Schnegg, R., 129.Schneider, F., 233.Schneiderhohn, H., 276.Schoeller, W., 240.Schoep, A., 289.Schopf, C., 178, 200.Schopp, K., 248, 249.Scholder, R., 91.Scholl, R., 171.Scholtz, H., 154.Schomer, A., 208.Schorigin, P., 147.Schramm, G., 85.Schreiner, E., 22.Schrodt, A., 130.Schroder, B’., 275.Schroeter, G., 164.Schuch, W., 207.Schudel, G., 195.Schuler, H., 304.Schutz, P., 232.Schulek, E., 221.Schultz, F., 250.Schulze, T., 263.Schumacher, H.J., 48, 50.Schuster, K., 174.Schwartz, G. M., 286.Schwarz, R., 52, 83, 85, 86.Schwenk, E., 242.Schwicker, A., 236.Schwingel, C. H., 61.Scofield, C. S., 258.Scott, W. E., 85.Seidel, C. F., 159.Seiwell, H. R., 295.Sekanina, J., 284, 294.Sekera, F., 257.Selby, W. M., 78, 98.Sen-Gupta, S.C., 152.Shapter, R. E., 257.Shepard, A. F., 125.Sherrill, R. E., 225.Shiba, K., 312.Shih, C., 237.Shimada, M., 186.Shindo, H., 154.Shive, J. W., 260, 261.Shoppee, C. W., 136, 143, 145.Short, 31. N., 276.Sieverts, A., 93, 94.Silberstein, G., 285.Simakova, T., 270.Simon, A., 82, 83, 88.Simon, E., 238.Simons, J. H., 79.Simonsen, J. L., 117, 155.Simpson, E. S., 293, 298.Simson, W., 129.Sinkovskaja, A. K., 231.Skalla, N., 82.Skopp, E., 232.Slawik, P., 230.Smedley, (Miss) I., 115.Smiles, S., 147.Smith, D. T., 276.Smith, E. F., 235.Smith, L. E., 187, 190.Smith, M. L., 41.Smith, S., 196, 197, 251.Smith, S. B., 93.Smoot, A. M., 231.Smyth, C. P., 66, 72.Snow, C. P., 46.Sobotka, H., 181.Socihs, L., 238.Soddy, F., 309.Soltys, A., 197.Sommer, A.L., 74, 300.Spacu, G., 233.Spacu, P., 233.Spath, E., 178, 180, 191, 201, 208.Speckmann, F., 85.Speight, E. A., 138.Spencer, L. J., 276, 298.Spencer, W. D., 41.Sperry, E. H., 67.Spilker, A., 112.Spinks, J. W. T., 48, 51.Spiwy, W. T. N., 191.Sponer, H., 49.Spong, H., 93.Sprinz, 157.Srikantia, C., 295.Stadnikov, G., 296, 297.Stahl, A. F. von, 297.Stamm, W., 76, 277.Stangler, G., 213, 215.Staples, L. W., 286.Starkova, Z. P., 93.Starrs, R. A., 94.Stas, M. E., 232.Staudinger, H., 128, 130, 132Stedman, E., 197.Stehle, K. B., 271.Stein, G., 84, 112, 113.Steinberg, R. A., 271.Steinbrecher, H., 297.Steinbrunn, G., 133.Steinfeld, H., 88.Steinke, E. G., 314.Stephan, M., 235.Stephens, M.M., 276.Stevens, R. E., 283.Stevens, T. S., 103, 147.Stevenson, J. W., 130.Steward, F. C., 255.Stieber, A., 80.Stieger, G., 50.Stilson, C. B., 277.Stilwell, F. L., 285INDEX OF AUTHORS’ NAMES. 33 1Stock, A., 80.Stober, F., 288.Stmen, R., 284.Stormer, I., 240, 242.Stoll, A., 196.Stone, J. F., jun., 102.Straib, W., 268.Street, J. C., 314.Streight, H. R. L., 128, 131.Stuart, H. A., 66.Stuart, J. M., 89.Stuart, M., 285.Stuhlmann, H., 89.Stutzinger, G., 150.Style, D. W. G., 52.Suciu, G., 233.Sutterlb, W., 104.Sugasawa, S., 180, 200.Sugden, S., 91.Sugii, Y., 154.Suginome, H., 198.Sullivan, J. T., 264.Sundermann, W., 95.Sundius, N., 290, 291.Sutherland, G.B. B., 62.Svagr, E., 81.Svirbely, J. L., 253.Sweeney, J. P., 237.Sweo, B. J., 93.Swinehart, C. F., 78.Switz, T. M., 119.Szent-Gyorgyi, A., 252, 253.Szper, J., 84.Taber, S., 293.Taboury, F., 288.Takagi, S., 154.Takei, S., 187, 188, 189.Takvorian, S., 82.Talts, J., 271.Tamam, K., 94.Tamiya, H., 271.Tamurrt, K., 198.Tanara, A., 89.Tanke, E., 80.Tao, W. S., 263.Tartar, H. V., 93.Taubadel, H., 111.Tausson, W. O., 272.Tawada, K., 56.Taylor, H. S., 99.Taylor, R., 104.Taylor, T. C., 135.Teller, E., 49.Terrey, H., 93.Tettamanzi, A., 79.Tettweiler, K., 156.Thakur, R. S., 139.Thatcher, L. E., 259.Thelen, H., 273.Thibaud, J., 307.Thiemann, W., 93.Thierfelder, K., 200.Thonessen, C., 93.Thomas, H.A., 131.Thomas, H. H., 281.Thomas, M. D., 236.Thomas, W., 254.Thompson, H. W., 45, 46.Thompson, T. G., 295.Thorns, H., 191.Thomson, (Sir) J. J., 278.Thomson, T., 147.Thornton, W. M., 54.Thorpe, J. F., 119, 136, 143.Thiiringer, V., 231, 235.Ti, S. P., 103.Tiedgens, V., 256.Tiffieneau, M., 147.Tilley, C. E., 282.Tillmans, J., 251, 252.Timmis, G. M., 196, 197.Timofiev, K., 94.Titeica, R., 63.Tiukov, D., 272, 273.Todd, A. R., 194.Todd, J., 124.Tokody, L., 285.Tolman, R. C., 45.Tom, W., 93, 94.Topley, B., 41, 42.Torres, C., 238.Torrey, G. G., 79.Toth, G., 131.Tower, 0. F., 95.Townend, D. T. A., 58.Trageser, G., 82.Trease, G. E., 227.Treibs, A., 211, 215.Trewendt, L., 89.Trier, G., 178.Trillat, J.A., 234.Trischler, J., 270.Trivelli, G., 116, 118.Troger, E., 282.Tromel, G., 280.Trogus, C., 129, 132, 134.Troitzsch, H., 280.Tronstad, L., 284.Trotter, J., 82.Trumble, H. C., 257.Ts’ai, L., 52.Tscherning, K., 241.Tschesche, R., 250.Tschudnowsky, M., 84, 185.Tschugaev, L. A., 230.Tsuboi, S., 290.Tunell, G., 279, 287.Turkiewicz, E., 86, 88.Turner, E. E., 69.Turner, J. O., 237.Turner, L. A., 49.Turner, W. E. S., 278.Tustanowska, L. von, 231.Tutundiid, P. S., 296332 INDEX OF AUTHORS’ NAMES.Udluft, H., 288.Uhlenbeck, G. E., 62.Ulmann, M., 134.Urazov, G. G., 95.Urey, H. C., 61, 63, 77, 302, 305, 307.Urey, H. M., 302.Uschakov, M. I., 88.Vaidya, W. M., 58, 59.Vakhrameev, N. A., 95.Valenta, 57.Vallesi, E., 296.Vareton, E., 52.Vargha, L.von, 252.Vassiliev, A. A., 231.Vastagh, G., 222.Vaubel, W., 230.Vavrinecz, G., 285.Veen, A. G. van, 153, 250.Vendl, A., 282.Venkateswaran, S., 60.Vernazza, E., 83.Vernon, E. L., 44.Verschoyle, T. T. H., 93.Vetter, H., 89.Vjewig, K., 232.Vigfusson, V. A., 280.Vilsmeyer, G., 270.Vinet, E., 261.Virtanen, A. I., 256.Vocke, F., 160.Vogele, K., 191, 192.Vogel, R., 93, 95.Vogt, K., 55.Vogt, R. R., 104.Volmar, Y., 229.Vukolov, V., 257.Wache, R., 295.Wada, M., 244.Waelsch, H. H., 273.Wagner, H., 280.Wagner, Heinrich, 259.Wagner-Jauregg, T., 151.Wainer, E., 300.Waksman, S. A., 296.Waldmann, H., 152.Walker, J., 107.Walker, O., 118.Walker, T. L., 293.Walling, E., 309.Walls, W.S . , 72.Walsh, G., 236.Walter, M., 208.Walter-LBvy, (Mme.), 94.Walton, E. T. S., 13, 307.Walton, J. H., 77.Wanka, L., 171.Wansbrough-Jones, 0. H., 51.Ward, F. A. B., 309, 310.Ward, G. W., 288.Ward, K., jun., 135.Wardlaw, W., 87, 92, 93.Warnat, K., 205, 207, 208, 209.Warren, F. L., 114, 119.Warren, H. V., 291.Warren, L. A., 147.Washburn, E. W., 77, 302.Washington, H. S., 277.Watkin, J. E., 259.Watson, E. M., 141.Watson, W. W., 303.Wattenberg, H., 287.Waugh, W. A., 251, 253.Weber, L. R., 61.Webster, E. T., 248, 249.Webster, H. C., 305.Wedekind, E., 156.Weegmann, E., 49.Wegener, W., 203.Weibke, F., 88.Weidinger, A., 134, 135.Weidlich, G., 253.Weil, K., 77.Weiss, H., 11 1.Weitendorf, K. F., 225.Wells, R. C., 283.Wenner, R. R., 50.Went, J. J., 60.Wenzke, H. H., 223.Werner, H. O., 268.West, W., 50.Westerhoff, H., 77.Westman, J., 294.Wetzel, K., 256, 265.Weyl, W., 279.Wheeler, R. V., 54, 55.Whitby, G. S., 111, 113.Whiting, G. H., 278.Whitmore, F. C., 98.Whittaker, C. W., 78.Whitworth, J. B., 180.Wibaut, J. P., 207, 208.Wiberg, E., 104.Widder, E., 229.Widdowson, E. M., 265.Wiebe, A. H., 295.Wieland, H., 49, 204, 205, 206,Wiemer, W., 121.Wien, M., 28.Wierl, R., 62, 80.Wigner, E., 40.Wiig, E. O., 47, 50.Wijk, W. R. van, 304.Wilcox, L. V., 258.Wild, G. O., 276.Wilkinson, (Miss) M. D., 127.Willemart, A., 173.Williams, A. F., 289.Williams, I., 124.Williams, J. W., 61.Williams, R. T., 252.Willstatter, R., 195, 295.239INDEX OF AUTHORS’ NAMES. 333Wilson, C. L., 95.Wilson, E. B., 66.Wilson, H. A., 54.Winchell, A. N., 276, 290.Wind, A. H., 152, 153, 154, 158.Windaus, A., 178, 250, 253.Windridge, M. E. D., 94.W i d e r , W., 171.Winterstein, A., 115, 119, 120.Winterstein, E., 178, 208.Wintner-HBlder, I., 86.Winzer, K., 296.Winzor, F. L., 127.Wittig, G., 121.Wohler, L., 91.Wohl, A., 182.Woldan, E., 115.Wolf, E., 52.Wolf, J., 265.Wolf, K. L., 72.Wolf, L., 84.Wolfe, H. S., 267.Wolff, H. A., 102.Wolff, J., 85.Wolker, W., 232.Wood, R. W., 228.Wood, T. B., 191.Woodward, L. A., 23.Woolf, B., 249.Woolvin, C. S., 131.Wormwell, F., 89.Wright, C. R., 141.Wright, F. E., 289.Wulf, 0. R., 45.Wunder, M., 231, 235.Wurm, O., 233.Wynne-Jones, W. F. K., 22.Wynn-Williams, C. E., 309.Yamaguchi, K., 95.Yanick, N. S., 95.Yoshimatsu, S., 232.Yoshimura, S., 295.Yoshimura, T., 289.Yost, D. M., 18.Young, M. N., 170.Young, R. C., 86.Zahn, C. T., 66.Zakomorny, M., 272.Zambonini, F., 93, 280, 289, 294.Zamoruev, G. M., 95.Zapffe, C., 287.Zappi, E. V., 236.Zechmeister, L., 131.Zeile, K., 215.Zickermann, J., 95.Ziegler, K., 88, 98.Zilva, S. S., 251, 252, 253.Zinke, A., 168.Zintl, E., 78, 85.Zoellner, E. A., 78, 98, 100.Zombory, L. von, 236.Zscheile, F. P., jun., 52.Zschiegner, H. E., 231.Zschokke, H., 116, 193.Zsivny, V., 293, 294.Zvjaginstsev, 0. E., 284

ISSN:0365-6217    

DOI:10.1039/AR9322900317

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

INDEX OF SUBJECTS.ABIETIC ACID, Structure Of, 159.Acetobacter xylinurn, action of, onAcetone, decomposition of, 44.Acetone, pentabromo-, determinationAcetylene, molecular structure of,polymerisation of, 112.photopolymerisation of, 52. .photochemical action of waterAcetylenic compounds, 105.Acids, production of, by moulds, 271.fatty, determination of, by con-ductometric titration, 224.unsaturated, lactonisation of, 107.Aconitic acids, cyano-, esters, 144.Actinium-C gnd -C’, a-particles from,Actinon, a-particles from, 31 1.Activity coefficients of electrolytes,Adiabatic processes, distinction of,lEtiomesobilirubin, 2 18.Ztioporphyrins, 211, 212.Agathic acid, structure of, 161.Alantolactones, structure of, 158.Alcohols, aliphatic, photo-oxidationof, 51.Aldehydes, photodecomposition of,48.unsaturated, formation of aldolsby, 115.Aliphatic compounds, 96.Alkali halides, handling of, withexclusion of air, 78.pozyhalides, 78.sulphites, photo-oxidation of solu-tions of, 51.Alkaloids, 178, 196.berberine, 179.cinchona, 183.ergot, 196.morphine, 17 9.papaverine, 179.quinoline, 17 8.isoquinoline, 179.glucose, 135.of, 237.63.with, 52.309.24.from non-adiabatic, 39.strychnos, 200.Alkanasul, 294.Alkyl chlorides, action of, withsodium vapour, 43.iodides, photodecomposition of, 50.Alloys, low-temperature, 79.Ally1 bromides, g-substituted, re-action of, with Grignard reagents,102.Aluminium, disintegration of, 16.halides, and their ammines, 80.determination of, with 8-hydroxy-quinoline, 232.Amethyst, 286.Amines, reactions of, 237.Ammonia, molecular structure of,Amphiboles, 290.Amylase, activation of, by sulphurAnalysis, colorimetric, 225.62.photodecomposition of, 50.compounds, 269.conductometric titration, 223.fluorescence, 227.inorganic, 229.organic, 236.quantitative, by separation ofhydroxides, 220.Andesite, Hungarian, 282.Anionotropy, 145.Anorthoclase, 292.Anthocyanins, 194, 267.nitrogenous, 195.Anthracene, structure of, 170.catalytic hydrogenation of, 164.Antimony trichloride, action of am-Apples, ripening and storage of, 265.Apple trees, calcium deficiency in,258.Ardealite, 294.Arsenic pentafluoride, physical pro-perties of, 87.Arsenic, detection of, with mercurybromide paper, 229.Arsenoklasi te , 29 3.Artemisin, structure of, 156.Ascorbic acid, 252.Ashtonite, 288.Aspergillus niger, nutrition of, 270.monia with, 85.Polyantimonides, 85.nitrogen distribution in, 264.production of acids by, 272.33INDEX OF SUBJECTS.335Atomic nucleus, structure of, 13.Atomic weight of boron, 305.of cssium, 303.of lithium, 304.of tellurium, 303.Atomic weights, standard for, 305.Atoms, electronegative character of,tercovalent, racemisation of, 64.19.Bacteria in coal, 295.Bacterium Sewanse, 287.Balances, 276.Barium, isotopes of, 304.Bavenite, 289.Beckmann reaction, 64.Beetroots, colouring matters of, 195.sugar, distribution of mineralnutrients in growth of, 259.Benzanthrene, structure of, 169.2:3-Benzanthracene, structure of, 165.Benzanthrone, structure of, 169.Benzene, structure of, 20.photobromination of, 52.photochemical action of, withhezachloride, structure of, 67.chlorine, 52.Benzene, chloro-2:4-dinitro-, reactionsof, 237.8 - Benzenesulphonylethylamino- 1 -ethylquinolinium iodide, resolu-tion of, 181.Benzenesulphonyl-8-nitronaphthyl-glycine, resolution of, 181.Benzoinoxime as analytical reagent,230.Berberine alkaloids, 179.Bergapten, structure of, 191.Beryl from Erythrza, 288.Beryllium, pure, 79.isotopes of, 303.bombardment of, by a-part,icles, 14.emission of neutrons from, 306.in minerals, 277.Fluoberyllates, 79.Betanidin, 196.Betanin chloride, 195.Bile acids, 178.pigments, 216.Bilirubic acids, 216.Biochemistry, animal, 239.plant, 254.Biotite, 291.Bisabolene trihydrochloride, synthesisof, 153.Bisabolol, synthesis of, 153.Bismuth oxide and sulphide, equili-brium of, 85.Polybismuthides, 85.Bismuth, det,ection of, 231.determination of, with cupferron,234.Bixbyite, 294.Bixin, structure of, 120.Blood, determination in, of mag-Bone, mineral constitution of, 293.Boron, atomic weight of, 305.emission of neutrons by, 306.crystalline, 80.trifluoride, physical properties of,hydrides, 80.organic compounds, 103.determination of, 221.hydrate, 87.oxides, 76.nesium, 232.87.Bromine fluorides, 87.Brucine, constitution of, 200.Brucinolic acid, 202.Brucinolone, 202.Brucinonic acid, 202.Bultfonteinite, 289.Bustamite, 290.Butadiene, /I-chloro-.See Chloro-prene.108.Butadienes, polymerisation of, 113.addition of hydrogen bromide to,Cadmium, determination of, 229, 233.Caesium, atomic weight of, 303.perbromide, 78.Calciferol, 253.Calcium ferrites, 90.oxide, bacterial precipitation of,287.Calt?itropsis araucarioides, triene-carboxylic acid from wood oilof, 117.Camphor, determination of, 238.Cancer, production of, by hydro-carbons, 246.Cannabinol, and its lactone, and itshydroxy- and nitro-derivatives,191.Cannabinolactonic acid, 192.Cannabis indica. See under Hemp,Indian.Carbamic acid, dithio-, complexferric salts of, 89.Carbethoxyglutaconic acids, esters,tautomerism of, 143.a-Carbethoxy-8-phenylglutaconicacid, ethyl ester, tautomerismCarbohydrates, photochemical pro-duction of, 52.Carbon tetrabromide, molecular struc-ture of, 63.tetrachloride, molecular structureof, 63.distance between chlorine atomsin, 68.of, 144336 INDEX OF SUBJECTS.Carbon monoxide, structure of, 18.pure, preparation of, 82.flame spectrum of, 58.burning, flame temperature of,infra-red rays from flames of, 56.moist, oxidation of, 46.photochemical action of, withammonia and amines, 52.dioxide, molecular structure of, 61.disulphide, flame spectrum of, 58.Carbonyl compounds, determinationselenide and sulphide, 82.sulphide, photodecomposition of,Carotene and vitamin-A, 249.action of antimony chloride on,249.&Carotene, 123.Castanite, 294.Catalase in plants, 268.Cells, photo-electric, 226.Cellulose, structure of, 127.synthesis of, 135.degradation of, 131.action of bacteria on, 296.cotton and wood, homogeneity of,Cement, magnesia, 278.Portland, determination in, of mag-nesium, 232.Centrifuge, separating vessels for, 276.Cereal straw, effect of potassium onstiffness of, 257.Chamosite, 29 1.Cherries, ripening of, 266.Chlorine, photochemical action of,with benzene, 52.with hydrogen, 50.55.of, 238.50.130.hydrate, 87.monoxide, molecular structure of,62.photodecomposition of, 50.dioxide, photodecomposition of, 48.Chlorites, 291.Chloroform, distance between chlor-Cldoroprene, addition of hydrogenCholesterol, 178.Chromium :-ine atoms in, 68.chloride to, 109.photodecomposition of, 52.synthetic rubber from, 124.Chromous iodide, 86.Perchromic acid, structure of, 86.Chromium, detection of, in mica, 291.Chrysanthemin, 267.Chrysene, structure of, 167.Cmchona alkaloids, stereochemistryCinnamyl chloride, Grignard reactionof, 183.with, 145.Citral, determination of, 238.Citric acid, formation of, by moulds,Citrulline, 244.Clays, 292.Japanese acid, 292.red, vanadium in, 292.Climate, effect of, on plant con-stituents, 261.Clkoptilolite, 288.Coal, origin of, 296.iodine in, 295.resins in, 297.brown, 297.Cobalt bases, 91.carbonyls, 89.Cobalt, detection of, 231.determination of, with a-nit,roso-j3-naphtho1, 235.Colorimeters, 225.a- and j3-Colubrines, 205.Conchoporphyrin, 21 1.Coniine, configuration of, 182.Co-pigments, 267.Copper sulphate pentahydrate, de-hydration of, 42.Copper, detection of, 231.determination of, 230, 233, 234.Coprobilirubin, 218.Coproporphyrin, 2 1 1.Coronadite, 294.Coronene, synthesis of, 171.Corrosion of metals, 77.Corynanthe johimbe, alkaloids from,Curynanthine , 207.Crassulchcece, carbohydrate metabol-Creedite, 294.Crocetin, structure of, 120.Crotonic acid, ethyl ester, addition273.207.ism of, 265.of ammonia and amines to.107.Cryptopyrrole, 210.Cub& 189.Cupferron as analytical reagent, 234.Cuprotungstite, 294.Cyanin, synthesis of, 194.Cyanogen, photopolymerisation of,52.fluoride, 82.Cyanates, detection of, 235.Cyciic compounds, energy relationsCyrtolite, age of, 283.of, 64.Dacites in Bohemia, 282.Danburite, 288.Decalin, preparation of, 152./3-Decalin derivatives, equilibria of,Decarboxyrisic acid, 187.n-Decatetraenol, 118.139INDEX OF SUBJECTS.337Deguelin, 189.Dehydrobilirubin, 219.Dehydrodeguelin, 190.Dehydroesermetholemethine, syn-thesis and resolution of, 199.Fhydrogeranic acid, 117.Derris extracts as insecticides, 189.Derrzk elliptica, poison from, 186.Derrisic acid, 187.Derritol, 188.Desethoxy dehydroeseretholemethine,199.Deuteroaetioporphyrin, 212.Deuterohsemin, 2 1 1.Deuteroporphyrin, 2 1 1, 2 14.Dialkyldithiocarbamates as analyti-cal reagents, 233.Diamines, aliphatic, as analyticalreagents, 233.Diamond, synthesis of, 283.Diazoacetic acid, ethyl ester, photo-decomposition of, 52.1 : 2 : 5 : 6-Dibenzanthracene, car-cinogenesis by, 247.Diethyldithiocarbamic acid, sodiumsalt, as analytical reagent, 233.apiro-5 : 5-Dihydantoin, resolution of,180.Dihydroiaoalantolactone, 157.1 : 2-Dihydroeremophilone, 2-hydr-p-Dihydrorotenone, 190.Dlhydroyobyrine, 209.Dimethylglyoxime as analytical re-Dinordeoxyeseroline, 198.Diopside, 290.Diphen y 1, o -fluoro - 0’- amino - , st ruc -ture of, 70.o-Diphenyl derivatives, optical activ-ity of, 69.Diquinolinoplatinous chlorides, is0 -meric, 93.Dolomite, 287.Dumortierite from India, 289.Dyes, action of, on enzymes, 246.Demi-helion,” 307.OXY-, 155.agent, 230.Earth, distribution of elements incrust of, 277.Earths, rare, basicity of, 81.bivalent compounds of, 75.Elecampane root, bitter principle of,157.Electrochemistry and quantum mech-anics, 34.Electrolytes, Raman spectra of, 23.minerals of interior of, 282.activity coefficients of, 24.thermochemistry of, 29.heats of(li1utiy of, 27, 30.strong, true dissociation of, 21.Elements, disintegration of, by pro-tons, 13, 307.Nos.85 and 87,300.Elsholtxione, 192.Enargite, 285.Enzymes of plants, 268.Equilibria in various systems, 93.Equol, 242.Eremphila M itchelli, ketones from,Eremophilone, and 2-hydroxy-, 155.Ergot alkaloids, 196.Ergotamine, 196.Ergotaminine, 196.Ergotinines, 197.Ergotoxine, 197.5-Ethoxy-3-methyl-3-/3-phthalimido-Ethyl bromide, decomposition of, 44.Ethylene, molecular structure of, 63.dichloride, Raman spectrum of, 66.chlorohydrin, activation of enzymesEthylene, dichloro-, equilibrium oftetrachloro-, photochlorination of,Ethylenediamine as analytical re-agent, 233.E t hylte traisoam ylammonium, 22 5.Eudesmol, structure of, 153.Euonymua atropurpureus, furan-8-carboxylic acid from, 193.Eyes, fatigue of, in colorimetry, 225.154.e t hy lindolenine, 1 9 8.by, 268.isomerides of, 66.51.Felspar, 292.Ferroanthophyllite, 291.Ferrobilin, 2 19.Fervanite, 293.Fish poisons.See under Poisons.Flames, 52.Flavylium perchlorates, 4’-amino-,Fluoberyllates. See under Beryllium.Fluorapatite, 293.Fluorescent “ stick,” 227.Fluoric acid.See under Fluorine.Fluorine, disintegration of, 16.ionisation in, 53.highly diluted, 55.196.oxides, 76.Fluorides, complex, 87.Hypofluorous acid, 87.Fluoric acid, 87.Fluorine, determination of, withboron in organic substances, 223.Fluorite, radioactive, 285.Fluorosulphonic acid, 85.Fluotitanates. See under Titanium.Formaldehyde, molecular structurephotochemical formation of, 52.of, 63338 INDEX OF SUBJECTS.Formaldehyde, formation of o-tolyl-carbinol from, 146.Fruit, changes during ripening andstorage of, 265.Fruit trees, nitrogen distribution in,264.Fuchsite, 291.Furan derivatives, 192.Furan-fl-carboxylic acid, synthesis of,Furfuraldehyde, determination of,Furfuryl chloride, action of, with193.238.potassium cyanide, 116.Gadolinite, 289.Galaxite, 286.Gallium, distribution of, 277.compounds, 81.trimethyl etherato, 98.Geiger-Muller counter for particles,Geochemistry, 275.Germanium dioxide, 82.Gennanates, 82.Germanium alkyls, 98.Glaucobilin, 2 19.Glaucocerinite, 294.Glucosides, anthocyanin, 194.Glutaconic acids, 140.Glutathione in plants, 269.Glycogen, structure of, 127.Gold ores, 284.Granite, 281.crystallisation of, 282.radium content of, 283.$aphite, 284.Green-earth ” in the Tyrol, 288.Grignard reaction, abnormal cases of,145.Grignard reagents, 99.Grunerite, 291.314.Hamatoporphyrin, 211.214.Haemin, constitution of, 210.Hsmoglobin, 215.Hamopyrrole, 210.Halides, heats of activation ofreactions of sodium with, 56.Hashish, 191.Heat of dilution of electrolytes, 27,30.Hedenbergite, 290.Helenin, 157.Helium, structure of nuclei of, 15.77.Helvite, 289.Hemp, Indian, constituents of, 191.Hessite, 285.Heterocyclic compounds, 178.Heulandite, dehydration of, 292.liquid, use of, for low temperatures,Hexabenzobenzene. See under Coro-Hexadienal, 115.cycZoHexadiene, dimeride of, 112.trans-Hexnhydrohydrindene deriv-atives, equilibria of, 139.Hexatriene ap-dibromide, isomeris-ation of, 116.Hexenoic acids, addition of hypo-chlorous acid to, 106.isoHexenonitrile, 137.Hexuronic acid, 252.Hirsutin, synthesis of, 194.Hirsutone, constitution of, 195.d-p-Homocamphor, preparation of,Homocyclic compounds, 136.Homopimanthrene, 160.Homoretene, 160.Hormones, follicular, 240, 242.sex, secondary, 239.testicular, 241.Hornblende, 290.Hydrazine, photodecompcsit i on of,Hydrocarbons, production of cancerHydrofluophosphoric acid.See undcrHydrogen, isotopes of, 77, 302.boiling point and vapour pressureflame spectrum of nit,rous oxideinfra-red rays from flames of, 56.burning, flame temperature of, 55.photochemical reaction of, withexplosion of mixtures of oxygenortho- and para-, 74.peroxide, new form of, 77.photolysis of solutions of, 52.sulphide, molecular structure of,flame spectrum of, 59.Hydrogen ions, change of fluores-cence with concentration of, 228.Hydromagnesite, 287.Hypofluorous acid. See under Fluor-ine.nene.151.50.by, 246.Phosphorus.of, 78.and, 59.polycyclic, 163.chlorine, 50.and, 46.61.Indene, dimeric, 1 11.Indicators, fluorescent, 228.Indole-2 : 3-dicarboxylic acid, 5 : 7-dinitro-, 201.Insecticides, derris root, 189.Inulin, structure of, 127, 130.Iodine in coal and water, 295.“ Ion-association ” theory, 25.nitrate, 88INDEX OF SUBJECTS.339Ipoh, 186.Iron. equilibria of cementation of, 90.corrokon of, 88.effect of chromates on, 86.oxides, equilibria of, with other’ oxides, 279.carbonyls, 89.ores, oxide, 287.Steel, equilibria in production of,determination in, of cobalt, 235.Iron, separation of, 235.Isoprene, action of acetic acid on,in presence of sulphuric acid,151.Isotopes, 301.Itaconic acid, formation of, by Asper-90.gillua itaconicus, 273.Joaquinite, 289.Kaolin, synthesis of, 292.Katangite, 289.Ketohydroxyczstrin, 240.Ketoyobyrine, 209.Kinetics, chemical, 39.Klebelsbergite, 294.Kolbeckin, 285.Kolm, age of, 283.Krausite, 294.Krypton, atomic radius of, 67.halides, 77.determination of, 296.“ Kupferpecherz,” 2 89.Lake water. See under Water.Lamps for photochemistry, 47.Lanthanum alloys, 81.Lava of Mt.Pelhe, 281.Lead, isotopes of, 304.in rocks, 283.tetrachloride, action of ammoniaon, 83.oxides, 83.tetraethyl, thermal decompositiondetermination of, 234.of, 99.Legrandite, 293.Lessingite, 289.Letovicite, 294.Leucophosphite, 293.Linkings, chemical, 17.multiple, heats of formation of, 73.Linoleic acids, selective hydrogen-ation of, 110.Linseed oil, utilisation of, by moulds,273.Liparite, Crimean, 281.Lithium, atomic weight of, 304.isotopes of, 304.Lithium, emission of neutrons by, 307.disintegration of, 307.chloride, solid solutions of, 78.alkyls, 98.Lycopenal, 122.Lycopene, structure of, 122.Lycoris squamzgera, fructosidesLycoroside, 265.from, 264.Magnesiosussexite, 294.Magnesium sulphides, 79.alkyl halides, 100, 101.Magnesium, determination of, withMagnetic moments, nuclear, 17.Maize, effect of fertilisers on sap of,Malvin, synthesis of, 194.Malvone, constitution of, 195.Manganese oxides, 88.Manganese, determination of, 234.Margarite, 291.Medlars, Japanese, ripening of, 266.Melsnterite, 294.Melons, water, citrulline from, 244.Menthone, determination of, 238.Mercury, isotopes of, 304.8-hydroxyquinoline, 232.261.solution of metals in, 79.diethyl, thermal decomposition of,determination of, with e thylenedi-mercurous, determination of, with99.amine, 233.cupferron, 234.Mesobilirubin, 216.Mesobilirubinogen, 2 16.Mesoporphyrins, 2 1 1.Metals, solubility of, in mercury, 79.corrosion and passivity of, 77.quantitative separation of, ashydroxides, 220.Meteoric iron, 297.Meteorites, 297.Methane, movement of flame inmixtures of air and, 54.4-Methylisoborneol, 148.8-Methylbutadiene, y-chloro-, asrubber precursor, 125.a- and 8-Methylcamphenes, 148./?-Met hy lcro t onalde h y de , self -c on -densation of, 11 6.Methyldecalins, preparation of, 152.Methylene dichloride, distance be-tween chlorine atoms in, 68.Methyleneazomethines, 145.Met h ylfurfuraldeh y de, determinationof, 238.Metrubrene, 176.Mica, 291.Minerals, specific gravity and hard-ness of, 276340 INDEX OFMinerals, metamorphism of, 281.age of, 283.halide, 285.oxide, 278, 286.phosphate, 293.silicate, 288.sulphate, 294.sulphide, 285.Mineralogical tables, 276.Molecules, structure of, from spectra,X-ray and diffraction data, 59.“ polarisation,” 19.Molybdenum sesquisulphide, 86.Molybdates, determination of, withMolybdenum cyanides, complex, 86.Monazite, age of, 283.Monochromators, 46.Montmorillonite, 292.Morphine alkaloids, 179.Mottramite, 293.Moulds, growth and metabolism of,Muds, 296.Mulberry leaves, sap from, 261.Muscovite, hydrothermal prepar-benzoinoxime, 230.270.ation of, 280.Nagatelite, 289.2’ : 3’-Naphtha-2 : 3-phenanthrene,structure of, 167./?-Naphthol, a-nitroso-, as analyticalreagent, 235.Narcotine in fruit and vegetables,251.Neon, isotopes of, 303.Nepheline, 289.Neutrons, 14, 305.Nickel, bivalent, structure of, 91.phosphides, 9 1.carbonyls, 90.determination of, with dimethyl-Nicouic acid, 190.Nitriles, ethylenic, synthesis of, 116.Nitrogen trichloride, photodecom-monoxide, molecular structure of,flame spectrum of hydrogen and,dioxide, photodecomposition of,per- or tetr-oxide, dissociation of,oxides, 84.glyoxime, 230.position of, 51.61.59.47.45.dl-Noreserethole, 198.Noresermethole, 200.Oats, distribution of mineral nutri-ents in growth of, 259.iUBJECTS.n-Octatrienol, 11 8.(Estrin, trihydroxy-, 240.OlefXc compounds, 105.Olive oi1,utilisation of, bymoulds, 273.Ooporphyrin, 21 1.Opsopyrrole, 210.Optically active compounds, deter-mination of configuration of, 182.in living matter, 64.Oranges, ripening of, 266.Orange juice, narcotine from, 25 1.Organic compounds, structure of, 20.Organo-metallic compounds, 98.Ornithine, effect of, on urea form-Osmium, isotopes of, 304.Overvol tage , 34.Oxalic acid, production of, byOxalyl derivatives, formation of, 114.“ Oxine.” See under Quinoline, 8-hydroxy-.o-Oxycarbanil, 208.Oxycyanogen, 82.Oxygen, explosion of mixtures ofn- and iao-Oxyrubrenes, 176.Ozone, molecular structure of, 62.photodecomposition of, 50, 51.detection of, 234.ation, 244.moulds, 273.hydrogen and, 46.Palladium compounds, structure of,detection of, 231.determination of, with a-nitroso-p-naphthol, 235.91.Pallasite, 298.Papaverine alkaloids, 179.a-Particles, analysis of groups of, 309.Passivity of metals, 77.Peaches, ripening and storage of, 265.Pear trees, Bartlett, nitrogen distri-bution in, 264.Pelargonin, synthesis of, 194.PenicilZium pbemclum, production ofacids by, 273.Pentamethylenedithiocarbamic acid,piperidine salt, as analytical re-agent, 234.5 : 6-cycloPenteno-1 : 2-benzanthra-cene, carcinogenesis by, 247.cycZoPentylideneacetic acid, ethylester, tautomerism of, 138.Peonin, synthesis of, 194.Permutites, base exchange in, 293.Persulphates.See under Sulphur.Perylene, structure of, 168.Petroleum, origin of, 297.Petrology, 280.Peucedanin, 19 1.Peucedarcum oficinale, poison from,191INDEX OF SUBJECTS. 341Pharmaceutical preparations, evalu-determination in, of copper, 234.Phenacyl esters, detection of, 237.Phenanthrene, structure of, 166.Phenanthrenes, synthesis of, 152.Phenanthripyridine alkaloids, 179.Phenylcrotononitrile, 137.a-Phenylethylamine, co&guration of,Phenylpentadienal, 115.Phlogopite, 29 1.Phosphorus trihydride, photodecom-position of, 50.trioxide, action of water on, 84.pentoxide, determination of, colori-metrically, 226.Hydrofluophosphoric acid, 84.Photochemistry, 46.Photodissociation, 47.Phyllopyrrole, 2 10.Physostigmine, 197.Pickeringite, 294.Pigments, cadmium-red, analysis of,Pimanthrene, 152.Pimanthrenequinone, 152.d-Pimaric acid, structure of, 159,a-Pipecoline, configuration of, 182.Piperine as mounting medium forminerals, 276.Plancheite, 289.Plants, effect of climate on con-stituents of, 261.mineral nutrients and growth of,254.intake and distribution of mineralnutrients by, 259.anthocyanin pigmenb of, 267.carbohydrates in, 264.enzymes of, 268.nitrogenous constituents of, 262.sap of, 260.growth of, in relation to boron, 257.in relation to calcium, 258.and nitrogen assimilation, 255.in relation to potassium, 256.Platinum compounds, structure of, 91.ores, 284.Diamminoplatinous chloridea, iso-ation of, 232.183.232.161.meric, 92.Plums, ripening of, 266.Poisons, fish, 186.Polyene-carboxylic acids, reductionof, 119.Polysaccharides, 126.Porphvrins, 211.Potas&rn chloride, conversion of, intonitrate, 78.pemulphate, photodecompositionof, 52.Potato plants, sap of, 261.Potatoes, activation of enzymes of,Predissociation, 47.Pregnandiol, 341.Propionaldehyde, photodecomposi-6-i8oPropyl-l: 2-benzanthraceneY car-o-Propyltoluene, 112.Protoactinium, chemistry of, 312.Protons, disintegration by, 13,307.Protoporphyrin, 211.Psittacinite, 293.Puberulic acid, 273.Pulegone, determination of, 238.Pumpellyite, 289.Pyroaurite, 287.Pyrocalciferol, 253.Pyroxenes, 290.Pyrroaetioporphyrin, 2 12.Pyrrole, pigments from, 209.Pyrroporphyrin, 212.268.tion of, 48.cinogenesis by, 247..Quartz, temperature of formation of,Quinaldine, synthesis of, 179.Quinine, photo-oxidation of, 51.Quinoline, 8-hydroxy-, as analyticalQuinoline alkaloids, 178.isoQuinoline alkaloids, 179.286.reagent, 231.Radicals, transformations of, 97.Radioactinium, a-particles from, 3 10.Radioactive constants, 308.Radioactivity, 299.of minerals, 283.Radium in granite and lava, 283.Radium-C’, a-particles from, 309.y-rays from, 310.Rain water.See under Water.Rays, cosmic, 313.y-Rays, emission of, 16.Reactions, additive, 105.Reagents, organic, for inorganicRefractivity in relation to structuralResin acids, 159.Resonance, 16.Retene, 152.Rhenium, 74.oxides, 88.Rhodium dioxide, 91.Rhodoporphyrin, 2 12.Rings, oxide, in natural products, 186.Ripidolite, 291.Risk acid, 187.River water.See under Water.organic, 96.chain, 45.analysis, 229.mobility, 114342 INDEX OF SUBJECTS.Rocks, analyses of, 280.Roeblingite, 294.Romanechite, 294.Rosickyite, 284.Rotenone, constitution of, 186.Rotenonic acid, 190.Rotenonone, structiire of, 189.Rubanols, stereoisomerism of, 185.Rubber, structure of, 123.volcanic, from Uganda, 38 1.synthetic, 124.solutions, action of hydrogen per-oxide on, 124.Rubidium periodide, 78.Rubrene, 173.Ruthenium, isotopes of, 304.Salicylaldoxiiiie ils analytical re-Salt domes, 285.Saluia sclareu, sclareol froin, 163.Samarium, radioactivity of, 299.Sanbornite, 289.Santonin, determination of, 238.Sapogenins, structure of, 163.Sarcolite, 289.Schairerite, 294.Sclareol, structure of, 163.Sea water.See under Water.Secretin, 242.Seeds, catalase in, in relation t oagent, 229.pans, 285.germination, 268.nitrogen exchange in, 263.ties of, 85.dioxide as oxidising agent, 86.Selenites, 86.Serandite, 289.Serendibite, 288.Sesquiterpenes, 152.Siderolite, 298.Silicon tetrachloride, molecular struc-ture of, 63.dioxide, volatility of, in steam, 278.Silicic acids, 82.Silicates, 82, 278, 288.structure of, 76.79.Selenium hydride, physical proper-Silver, molten, solution of oxygen in,compounds, bivalent, 75.ores, 284.Smalt, analysis of, 235.Sobralite, 290.Sodalite, 289.Sodium, conductivity of, in liquidammonia, 37.heats of activation of reactions ofhalides with, 56.phosphates, 84.ethyl and methyl, 99.Soils, 296.Solids, reactions of, 4 1 .Sorbic acid, reduction of, 119.addition of hypochlorous acid to,109.Sorbic acids, reaction of, withhydrogen, 109.Sorbyl chloride, action of, withpotassium cyanide, 116.Soya beans, mineral nutrition of, 259.germinating, nitrogen exchange in,263.Spadaite, 289.Spectra, flame, 57.molecular, 59.Itaman, of eleclrolytes, 23.Spectrographs, 59.Spinels, 76, 277.Stannite, 285.Starch, structure of, 127.hydrolysis of, 134.Stearolic acid, hydration of, 107.Steel. See under Iron.Stereoc hemis try, 64.Steric hindrance, 21.Strontium, isotopes of, 304.Strychnidines, 204.Strychnine, constitution of, 300.$-Strychnine, 205.Strychnos alkaloids, 200.Sub-atornic phenomena, 299.Sugars, analysis of, 237.Sulphur, flame spectrum of, 5s.of heterocyclic compounds, 180.distribution of, 277.dioxide, molecular structure of, 6 1 .Sulphitcs, oxidation of, in solution,Persu lpha tes, determination of,Thiosulphates, detection of, in235.iodomet,rically, 236.presence of sulphur oxy-acids,233.Sulvanite, 286.Supercondiictivity, 77.Systems, various, equilibria in, 93.Tables of isotopes, 301.mineralogical, 276.Tautomerism, 136.three-carbon, 136.Tektites, 297.Tellurium, atomic weight of, 303.hydride, physical properties of, 85.Tephrosiu, poisons from species of,189.Tephrosin, 189.Terpenes, 147.Testicles, substance increasing tissuepermeability from, 243.Tetraisoamy lammonium iodide, con -ductonietric titration of, withethylsodium, 225INDEX OF SUBJECTS.343Tetrahydropapaverine, synthesis of,180.Te trame t h y ldiaminodipheny lme thaneas analytical reagent, 234.Tetramethyltetrapropylporphyrin,212.Thallium triethyl, 98.Thianthren, and its disulphoxides,structure of, 185.Thiocyanic acid, complex ferroussalts, 89.Thiosulphates. See under Sulphur.Thorium, ranges of a-particles from,310.Thorium-C, a-particles and y-raysThorium-C', a-particles from, 309.Thucholite, age of, 283.Tin :-nitride, 83.from, 311.Stannic bromide and chloride,molecular structure of, 63.chloride, action of ammonia on,83.Tin, determination of, with cup-Tissues, determination in, of boron,Titanium tetrachloride, molecularStannous nitrate, 83.ferron, 234.222.structure of, 63.iodates, complex, 83.Fluotitanates, 83.Titanium, determination of, withcupferron, 234.Tomatoes, calcium deficiency in, 358.Tourmalines, black, 288.Toxicarol, 189.Tremolite, 290, 29 1.Trialkylarsines, 103.Trialkylstibines, 103.Tri-tert.-butylboron, 105.Triene acids, conjugated, syntJhesis of,Tricpdopentadiene, 1 13.Triphenylene, structure of, 167.Triphenylrnethyl o-tolyl ether, groupmigration in, 147.Tri-sec.-propylboron, 106.Tuba root, 186.Tubaic acid, constitution of, 168.Tubatoxin, 186.Tungsten in Bolivia, 277.carbides, 87.oxychloride, 87.Tungstates, determination of, 234.10-Tungstogermanic acid, salts of,Turquoise, 293.117.82.A'-Undecylenic acid, addition ofhydrogen bromide to, 107.Uranium, detection of, by fluor-Uranium-I and -11, ranges of a-Urea, distribution of, in plants, 263.formation of, in the body, 244.Urease, action of dyes on, 246.Urine of pregnant maros, equol from,Uroporphyrins, 2 11.Uteroverdin, 219.escence, 229.particles from, 310.242.Valency, measurement of angles of,Vanadinite, Spanish, 293.Vanadium, distribution of, 277.Vanadates, detection of, 234.Vanadium organic compounds, 85.Vanadium, detection of, with di-methylglyoxime, 230.Vaterite in snail-shells, 287.Veszelyite from Momvia, 293.Vines, effect of variations in sap of,on fruit yield, 261.8-Vinylacrylic acid, addition of hypo-chlorous acid to, 109.a-Vinylcinnamic acid, 115.Vitamin-A, 248.Vitamin-B,, 250.Vitamin-C, 251.Vitamin-D, 253.Volumes, atomic and molecular, 278.Vomicine, 205.Vomicinic acid, 206.72.Walnut oil, utilisation of, by moulds,Water, molecular structure of, 6 1.natural, radioactivity of, 283.relation of iodine content of, todetermination of magnesium hard-Lake water, Japanese, 395.Rain water, formaldehyde in, 295.River water of the Mississippi, 295.Sea water, properties and con-determination in, of copper, 234.Well water, E.Indies, magnesiumiodide in, 295.273.goitre, 295.noss of, 232.stituents of, 295.Wavellite, blue, 293.Well water. See under Water.Wheat, mineral nutrition of, 259.Wilson cloud-chamber, 314.Wischnewite, 289.Wurtz reaction, 100.Xanthobilirubic acids, 217.Xanthotoxin, structure of, 191344 INDEX OF SUBJECTS.Xenon, determination of, 296.Yobyrine, 207.Yohimbene, 207.Yohimbines, 207.Yohimboaic acid, 208.Yohimbols, 207.Ytterbium halides, 81.Zeolites, 292.Zinc, effect of, on growth of Asper-gillus niger, 271.chloride, pure, 79.Zirconium bromides, 75.Zirconium, determination of, withcupferron, 234.Zunyite, 288

ISSN:0365-6217    

DOI:10.1039/AR9322900334

出版商:RSC    

年代:1932

数据来源: RSC