摘要:

J O U R N A L OF THE CHEMICAL SOCIETY. TRANSACTIONS. Qommittee af @ubItafian : H. 'E. AR3fSTRONG, Ph.D., P.R.S. J. DEWAR, LLD., F.R.S. 1 W. J. RUSSELL, Ph.D., F.R.S. WYNDHAM R. DUNSTAN, M.-4., F.R.S. 1 J. MILLAR THOMSON, F.R.S.E. A. VERNON HARCOFRT, D.I.A., B.R.S. F. S. KIPPING, D.Sc. I W. RAMSAY, Ph.D., P.R.S. T. E. THORPE, Ph.D., F.X.S. i W. A. TILDEN, D.Sc., F.R.S. R. MELDOLA, F.R.S. I gbitrrr : C. E. GROVES, F.R.S. Sub- @bitor : A. J. BREENAWAY. 1896. Vol. LXIX. L O N D O N : GURNEY & JACKSON, 1, PATERNOSTER ROW. 1896.LOKDOS : H.4RRISOX AND SOXP, PRINTERS Ih' ORDlNAUY TO HER MAJESIY, SP. MARTIS'S LANE.C 0 N T E N T S . PAPERS READ BEFORE THE CHEMICAL SOCIETY. ].-Influence of Tempemtux on the Refractive Power and on the Refraction Equivnlei~ts of Accfylacetone and of Ortho- 2nd Para-toluidine.By 11'. H. PERKIN: Pli.D., F.R.S. . 1 I I.-The Alkaline Reduction of 1\4etanitraniline. Ry RAPHAEL III.--'Fbe Chemistry of Dibromopropyvltliiccarb~i~*i~e : mid the Action of Bromine and of Iodine on Allylthiourea. By 1V.- Studies of the Terpeiies and Allied Compounds. New Derivatives from cc-3I)ilsi~omocan1phor, By MAR~IY OSELOW FORSTER, Ph.D., First Salters Company's Research 1''ellow at the City and Guilds of London Institute, Central Tech- iiical College . . 36 V.-w-Bromacnniphoric acid. By F. STAXLEY KIPPIXG, Ph.D., D.Sc. . . . 61 TL- Efflorescence of Double Ferrous Aluminium Sulphate on Bricks exposed to Sulphur Dioxide. By DATrD PATEXFON . 0; TIT.-Some Derivatives of Anthraquinone. By EDTI'ARD SCHUNCK, Ph.D., F.R.S., and LEO ~\IIARCHLE\I'SKI, Ph.D.68 VII1.-Researches on the Terpene. VJ. Products of the Oxida- tion of C'ainphene, Camphoic acid, and its Derivatives. By JAMES ERNEST ~ ~ A K S H and JOHN AUDYMAN GA4RDYER . 74 1Y.-The Action of Sodium Alcoholate on the Acid Amides. By JFLWS BEREND CotrEN, Ph.D., and \ ~ I L L I A ? I I HENRY X.-Note on the Electrolptic Conductivity of Formanilide and XI.-On certain Phenylthiocarbamates. By HEXRY LLOTD XI.-Periodides of Theobroinine. By GEORGE ELL~O'J'T SHAW . 102 X1TI.-Ethereal Salts of Active and Inactive Monobenzoyl-, Jlibeazoyl-, Diphenacety I-, and Dipropionyl-glyceric acids. B y PP~RCY FAI:A~AI- FRANKLAND, Ph.P., B.Sc., F.R.S., aiid hl ISLDOLA, F.R.S., and ERK'EST R. AKDREWS. . . 7 A~JGUSTUS E. DIXON, M.D. . . 17 ARCHDEACON, B.Sc., The Yorkshire College.91 'f'hioformanilide. By THOMAS EWAN, B.Sc., Yh.D. . . 96 SNAPE. D.SC., PI1.n. . . 9@ J O B N 11A4CGREC;oR, 3I.B. . . . . . 104i r CONTEYTS. XIV.-Rotation of Opt ic.ally Active Ccimpouiids in Organic Solvents. By PERCY F. FRAKKLANI,, J'h. D., F.R.S., and ROBERT HOVSON PICKARD, B.Sc. . SV.--The Molecular Voliimes of Organic Snbs tances in Soln- tion. By W. W. J. Nicol, M.A., D Sc., F I.C. . XV1.-Action of Sugars on Ammoiiiacal Silver Nitrate. r',y JAMES HENDERSON, R.Sc., 1851 Exhibition Scholar, Unt- versity College, Dundee . XVII. --The Xolecular Weight and Poraiula of Phosphoric Anhydride and of Metaphosphoric aci(1. Bp WJLLIAM AUGUSTUS TILDES, I).&., E'.R.S., and ROBERT E. BARNETT, B.Sc., Assoc. R.C.S. . XVITL-On yPhenoxy-clei ivi-itives O F 2hlonic ncid and Acetic acid, and vniious Compounds used in the Syiithesis of these acids.By WILLIAM I3 EWBY RENTLEY, XDWARD HAWORTH, alid TVIrmAM HENKY PERKIN, jun. X1X.-Note on the Preparation of Glycol. By EDWARD HATVOKTH, B.$c., and WILLIAM HENRY PEL~KTS, Jun. SX.-The Oximes of Benzaldehyde and their Derivatives. XX1.-Transformation of the Alkylammonium Cyanates into the corvespondin? Urens. By JAMES WALKER, I).%., Ph.D., J A M E S R. APPLEYARD, F.C.S., University College, Dundee . XXI1.-Luteolin. Part I. H y ARTHUR G. PERKIN, F.R.S.E. . XXIIL-Lead Tetrscetate and t h e Plumbic Salts. By ARTHUR HUTCHTKSON, M.A., Ph.D., and W. POLLARD, B.A., Ph.D. . XX1V.-The Acetglene Theory of Luminosity. By VIVIAN B. LEWES, Royal Naval College, Grcenwich .XXV.-Solu tion and Diffusion of certain Metals in Mclrcury. By W. J. HUWHREYS . . XXV1.-The Symmetrical Dimethjlsucciaic acids. By WILLIAM ARTHUR BONE and WILLIAM HENRY PERKIN, J u n . XXVI1.-Note on the aa,-Dimethylalutaric acids. By lTTILr.raM ARTHUR BOKE and WILLIAM HENRY PERKIN, Jun. . XXVII1.-Cis- and trmzs-Me thyli~opropylsuccinic acid. By WILLIAM HENRY BENTLEY, WILL~AM HENRY PERKIK, J u n . , and JOCELYN FIELD TIIORPE . By T. B. WOOD, Secretary to Cambridge and Counties Agri- cultural Education Scheme . XXX.-The Production of Naphfhaleiie and of Isoqninoline Derivatives from Dehydmcetic acid. By JOHN NORMAN COLLIE, Ph.D., F.R.S.E., and N. T. 31. WILSMOI~E, 3l.S~. . . . By CHARLES IiZ. LUXMOORE, D.Sc. . XX1X.-Available Potash and Phosphcric acid in Soils.PAGE I23 142 145 154 16 i 175 177 19:3 206 21% 226 24s 253 268 2iO 293CONTESTS. V PAaE XXX1.-Isomeric 7r-Bromo-a-Nitrocamphors. By ARTHUR LAPWORTH, D.Sc., and FREDERICK STANLEY KIPPING, Ph.D., D.Sc. . . 304 XXXI1.-Note on the Formation of Camphorquinone from a-Chloronitrocamphor. By ARTHUR LAPWORTH, L).Sc. . 322 XXXII1.-The Action of Lead Thiocyanate on the Chloro- carbonates. Part I. Carboxyethylthicarbimide and its Derivatives. By ROBERT ELLIOT DORAN . . 324 XXX1V.-Connection between the Atomic Weight of Con- tained Metals, and the Crystallographical Characters of Isomorphons Salts. The Volume and Optical Relationships of the Potassium, Rubidium, and Caesium Salts of the Monoclinic Series of Double Sulphates, R2M( S0,),,6H20. XXXV.-Comparison of the Results of the Investigations of the Simple and Double Sulphates containing Potassium, Rubidium, and Cmium, and General Deductions therefrom coucerning the Influence of Atomic Weight on Crystal XXXV1.-The bearing of the Results of the Investigations of the Simple and Double Sulphates containing Potassium, Rubidium, and CEsiurn on the Nature of the Structural Unit.By ALFRED E. TUTTON, Assoc. R.C.S. . . 507 XXXVI1.-An Auxiliary Assay Balance. By ROBERT LAW . 526 XXXVII1.-Contributions to the Knowledge of Ethylic Aceto- acetate. Part I. Acetonylmalic acid. By SIEGFRIED RUHEMANN, Ph.D., M.A.,and E. A. TYLER, Scholar of St. John’s College, Cambridge . . 530 XXX1X.-Analysis of the Water from the Dropping Well at Knaresborough, in Yorkshire. By B. A. BURRELL . 536 XL.-Charas.The Resin of Indian Hemp. By THOMAS BAR- LOW WOOD, M.A., W. T. NEWTON SPIVEY, M.A., and THOMAS XL1.-The Constitution of a new Dibasic acid, resulting from By HENRY J. HORSTMAN By ALFRED E. TUTTON, Assoc. R.C.S. . . 344 Characters. By ALFRED E. TUTTON, Assoc. R.C.S. . . 495 HILL EASTERFIELD, M.A., Ph.D. . 539 the Oxidation of Tartaric acid. FENTON, M.A. . . 546 Annual General Meeting . . 563 XL1I.-Hofmnnn Memorial Lecture.-Personal Reminiscences of Hofmann and of the conditions which led to the establish- ment of the Royal College of Chemistry and his sppoint- ment as its Professor. By Lord PLATFAIR, G.C.B., F.R.S., &C. . 575 The History of the Royal College of Chemistry and Reminiscences of Hofmann’s Professorship. By Sir F. A. ABEL, Bart., K.C.B., F.R.S., &c.. 580 A 2Vi CONTENTS. PAGE The Origin of t’he Coal-Tar Colour Industry, and the Con- tributions of Hofmann and his Pupils. By W. H PERKIN, PhD., D.C.L., F.R.S., By HENRY E. ARMSTRONG . Obituary Notices . XLII1.-Condensation of B e n d with E thylic Acetoacetate. By FRANCIS R. JAPP, F.R.S., and G. DRUCE LANDER, B.Sc. (Lond.) . XLIV.-E lectrolysis of Potassium Allo-e thy lic Camphorate. Part 11. By JAMES WALKER, Ph.D., D.Sc., and JAMES HENDERSON, R.Sc., University College, Dnndee . XLV.-The Explosion of Cyanogen. By HAROLD BAILY DIXON, M.A., F.R.S., E. H. STRANGE, B.Sc., and EDWARD GRAHAN, B.Sc. . XLV1.-The Mode of Formation of Carbonic acid i n the burning of Carbon Compounds. By Professor HAROLD BAILY DIXON, M.A., F.R.S. . XLVI1.-On the Detonation of Chlorine Peroxide.By Pro- fessor HAROLD BAILV DIXON, M.A., P.R.S., and J. A. HARKER, D.Sc. . XLVI1I.-Morin. Part I. By HERMANN BABLICR, Ph.D., and ARTHUR GEORGE PERKIN, F.R.S.E. . XL1X.-Luteolin. Part 11. By ARTHUR GEORGE PERKIN, F.R.S.E. . L.-Constitution of the Cereal Celluloses. By CHARLES FREDER~CK CROSS, EDWARD J. BEVAN, and CLAUDE SXITH . L1.-Ethereal Salts of Optically Active Malio and Lactic acids. By THOMAS PURDIE, F.R.S., and S~DNEY WILLIAMSON, P1i.D. LL1.-The Hydriodides of Hydroxylamine. By WTNDHA )I R. DUNSTAN, F.R.S., and ERNEST GOULDING LII1.-The Determination of the Composition of a “ White Sou ” by a Method of Spectragraphic Analysis. By WALTER NOEL HARTLET, F.R.S., Professor of Chemistry, Royal College of Science, Dublin. . By WALTER NOEL HARTLEY, F.R.S., Professor of Chemistry, Royal College of Science, Dublin .LV.-Metadichlorobenzene. By FREDERICK D. CHATTAWAY, M.A., and ROBERT CECIL TURLE EVANS . LV1.-Halogen Additive Products of Substituted Thiosinn- amines. By ACGUSTIJS E. DZXOX, M.D. , LVI1.-Acidic Thiocarbimides, Thioureas, and Ureas. By AUGUSTUS E. DIXOS, M.D. . Notes on Hofmann’s Scientific Work. . L1V.-On the Temperatme of Certain Flames. . 596 63 7 733 736 748 759 7 74 i 8 9 ‘792 799 804 81 8 539 842 844 848 851 8.55CONTENTS. v ii PAGE: LVII1.-Carbon Dioxide. Its Volumetric Determination. By WILLIAM HENRY STl1oxs, D.P.H. (Oxon), and F. R. STEPHENS . , SG9 LIX.-The Atomic Weight of Japanese Tellurium. By MASUMI CHIKASHIG~, B.Sc. . . S8l Helmholtz Memorial Lecture. By GIWRGE FRANCIS FLTZGERALD, M.A., D.Sc., k'.RS.. . 885 LS.-Derivatives of Cimphoric acid. Part I. By FREDERICK SIAXLEY KIPPIEG, P h . I ) . , D Sc. . . 9113 I,XI.-Sub&mces exhibiting Circular Polarisation both in the Amorphous and Crystalline states. By WlLLIAnr JACKSON P O P E . . 9 i l LXlI -The Diphenylbenzenes. I. Metadiphenylhenzene. By FREDE~~ICK I). CBATTAWAY, M.A., and HOBE~~T CECIL T'URLE EVANS . . 080 LXII r.-DimethoxydiphenylmethRne and some of its Homo- LXIV.-On certain Views concerning the Condition of the Dissolved Substance in Solutions of Sodium Sulphate. LYV.-Iodoso- and Todoxy - benznldehjdes. By THO~UAS STEWART PATTERSON . . 1009 LXVI.-The Action of Bromine on Pinene with reference to the question of its Constitution. By WILLIAM AUGUSTCS LXVI1.-Liberation of Chlorine during the Heating of a Mixtare of Potassic C hlorate and hfauganic Peroxide.(Second LXVII1.-The Rotation of Aspartic acid. By R. MERVYN C. LXTX.--On Magnetic Rotatory Power, especially of Aromatic Compounds. By WILLIAM HEERY PERKIN, LL.D., Pli. D., F.R.S. . 1025 By JOHN THEODORE HEWITT, M.A., D.Sc., PhD., and HENRY E. STEVENSOX . . 1257 LXXT.-The Condensation of Chloral with Resnrcinol. By JLHN THEODORE HEWITI', 3l,A,, D.Sc., Ph.D., and FRANK LXXI1.-Double Sulphides of Gold and other Metals, or the Action a t a Red Heat of Sulphur on Gold Mhen alloyed with ot,her Metals. By J. S. MACLAUKIN, B.Sc., University College, Auckltind, New Zealand . . . 1260 lopes. By JOHN E. ~ ~ A C K E N Z I E , Ph.D., B.Sc. . . 983 By R. E'. D'ARcY, M.A. . . 993 TILDEN, T).Sc., F.Rl.S.. . . 1009 Note.) By HERBERT MCLEOD, F.R.S. . . 1015 MARSHALL, A.R.C.S. . . 10%2 LXX.-The Three ChlorobeDzeneazosalicylic acids. G. POPE . . 12&v iii CONTENTS. PAC3 E LXXII1.-The Relative Weights of Gold and Sil rer dis- solved by Potassiiim Cyanide Solutions from Alloys of these Metals. By J. S. MACLAUKIN, B.Sc., Uiiirersity College, Auckland, New Zealand . . 1276 By JANES WALLACF: WALKER, M.A., Ph.I)., 1851 Exliibitioii Science Scholar, St. Andrew’s University LXXV.-Action of Fornialdehydc 011 Pheiijlhpdrazine a n d on some Hjdrazones. By JAMES WAI,LACE W A L K E R , AI.A., P1i.D. . 1280 LXXT’I.-The Colouring Principle contained in the Bark of M y ~ i c a way;. Part I. Ily ARTHUR GEORGE Y E ~ K I N and JOHN JAMES HunrvEr, . . 1.257 LXXVII.-Occurrence of Quercetin in the Outer Skiiis of the Bulb of the Onibn (Alliiim wpa). By AKTHW GEORGE P E R K I N and JOHN JAJrEs HUMNEL , .1295 LSXVlI1.-An Apparatus for showing Experi rnents with Ozone. By GEORGE S. NEWIH . . 129s LXXIX.-Colouring Mtt ter of Sicilian Sumach, R h z ~ s coi-iwin. By ARTHUR GEORGE PEEKIN, F.R.S.E., and GhORGE YOUXG ALLEN. . . 1299 LXXX.-The Colourinq Matter of Qzcwhracho CoZorntlo. By LSXX1.-The Chemicd Inactivity of Rontgen Rays. By HAROLD BAILY I j i x O N and H. BlCERETON BAKER . . 1308 LXXX 11.-Position-isomel ism and Optical Activity ; the Me- thylic and Ethylic Salts of ortho-, rneta-, and para-Ditolnyl- tartaric acids. By PERCY P. FRANKLAKD, Ph.D., F.K.S., and YREDEGICK MALCOLJI WHARTON, A.I.C., Priestleg and late LYXXIII.--Contributions to the Chemistry of Phenol Deriva- tives.By HAPHAEL MELDOLB, Y. Rr.S., GEORGE HA~~OLD By JAMES WALKER, D.Sc., Pli.D., Professor of Chemistry, and JAMES R. APPLEYARD: F.C.S., Lecturer on Dyeing, University College, Dundee . . . 1334 By ARTHUR RICHARDSON, Ph.D., and EMILY C. FORTET, B.Sc., University College, Brlstol . . 1349 LXXXV1.-Note on t h e Action of Light on Ether. B.y ARTHUR RICHARDSOK, Ph.D., and EMILY C. FORTEY, B.Sc., University LXXXVII.-The Constitution of Lnpachol and its Derivatives. Part JII. The Structure of the Anijlene Chain. By SAML-ET, C. HOOKER . . . . . . 1355 LXXIV.-Electrolysis of the Salts of nloiillydroxy-a..ids. . 127$ I ARTHUR GEORGE PB:RIi[N, F.I<.S.E., and OSM’ALD GUNKELL . 1:30;3 Forster Scho!ur i n Mason College, Bii*mingham .. . 1309 ~ V O O L C O r~’, and EDWARD W R A Y . . 1321 LXXX1V.-Abmrption of Dilute Acids by Silk. LXXXV.-Action of Light on Amy1 Alcohol. College, Bristol . . 1:352CONTENTS. ix PAGE LXXXVJI1.-Lornatiol (Hydroxyisolapachol). By SAMUEL C. HOOKER . . 1381 LXXX1X.-Contribntions to the Knowledge of the /%Ketonic acids. Palat IT. B y STEGFRIED RuHEalax~, Ph.D., M.A., and C. G. L. WOLF, B. A., X.D. . XC.-Forins tioil of Pyrasolone Derivatives from Chloro- XC1.-Studies of the Terpenes and allied Compounds. Note on Ketopinic acid-a. product of tho Oxidation of the Folid HydrichToyide (Chlorou;ini),hydrene) p r e p a ~ e d fl-om Pinens. By HEXRY E. AJWSLRONG . . 1397 Lothar 3Ieyt.r Memorial Lecture. By P. PHILLIPS BEGSON, MA., I).&., F I.C.. . 1403 XCI1.- -Acid Compounds of Natural Yellow Colonring Matter. Part II. Ey A. G. PERKIX, F.R.S I<. . 1439 XCII1.-Studies on CitraJinic acid. P a r t IT. By WILLIAM XCIV.--TE,e Action of cerhin Acidic Oxides on Salts of Hydroxy-acids. 111. 1Jy GEORGE G. KEKDEBSON, D.Sc., If.&, and JOHS X. BARR . 1451 XCV.-Sonie 1)eriv:itives of Propionic acid, o f Acrylic acid, axid of G l u t a ~ i c acid. By WILL~AM H E > i R Y PtilLKLX, Sun. . . 14S7 XCV1.-Action of F:thylic p-Iodopropiounte oil t h e Sodium dcrivstive of Etliylic Isopropylmiilonate. By J. L. HEIS u; . 1383 funiaric acid. By STEC;FKIED RUHEUAKN, Ph.D., M.A. . 1394 JAMES SELT,, &LA., 1l.I.C. . . I447 and T V I L r , r m HESRY PERKIS, jun. , . 1506 XC VIL-Note on y-Acetobut-yric acid, CH,*C 0.C H,.C €I2- C H,. C 0 0 13. By WILLTAX HEYEP I3 ENTLEY and WILLIAM HEXRY PERKIN, jun. . . 1.510 XCVII1.-Action of Cliloroform an3 Potassium Hydroxide on Metsmidobenzoic acid. XC1X.-Contribn tions to OUY Knowledge of the Aconite Allta- lo'icls. Part XIII. Or1 Atisine, t h e A!kaloYd of A~:o?zitmz j'~etemphylliina. By HOOPER ALBERT DICKISSON JOWET r, D.Sc. Lond., Research Fellow of the Pharmaceutical Socier>y 151s C.-Effect of Heat on Aqueous Solutions of Chrome Alum. By MARGARET DOUIE DOGGAL . . . . 1526 CL-l'he Kefraction Constants of Crystalline Salts. By WILLIAM JACKSON Pom . . . 1530 CI1.-Derivatives of Campheneaulphonic acids. By AKTHUR LAYWORTH, D.Sc., and FREDER~C STANLEY KIPP~NG, Ph.D., D.Sc. . . 1546 CI1I.-'rhe Colouririg Matters occui-ring in various British Plants.Part I. By ARTHUR GEORGE PEXKIN and JOHN JAMES HUMMEL . . . . 1566 By WALIER JOHN ELLIOIL'T, 31.21. . 1513x COST ENTS. PAQ E CIV.-The Constitation of the so-called “ Nitrogen Iodide.” By FREDERIC D. CHATTAKAP, R.I.A., Christ Church, Oxford 1572 C V.-Posit,ion-isomerism and Optical Activity ; the Compara- tive Rotatory Powers OF the Dibenzoyl- and Ditoluyl- tartrates. By PERCY FBANKLASL), Yh.D., E’.R.d., and FREDEiZICK MALCOLM WHAItTOA, A.1.C . . . 1583 ~VI.-Thiocarloiniides derived from Complex Fatty acids. By CVI1.-The Carbohydrates of Barley Straw. By CHARLES CVII1.-The Reduction of Nitrososulpliates. Ry EDWARD DIVERS, CIX.-Imidosulplionates. Part I J. By EnwAizD DIVEIIS, X.D., CX.-Amidosulphonic acid. By EDWARD DmI;iis, X U . , F.R.S., C~XI.-Molecular Conductivitg of Amidosnlphonic acid. By J ~ J I SAKUIIAI, D.Sc. (Japan), Professor of Chemistry, 1 inperi a1 University , Japan . 1654 (3x11.-Physiological Action of Amidclsulphoiiic acid. By OSCAR LOEV’, P1l.n. . , 1662 CXI1I.-Economical Preparation of Hydroxy lamine Sulphste. By EDWARD DLVERS, M.D., F.R.S., and TAMKMASA HACA, D.Sc., F.C.S. . . 1665 CX 1V.-How Mercurous and I\iIercixric Salts change into each other. By SEIHACH~ HADA, B.Sc. (Japan) . . 1667 CXV.-Solution and Diffusion of certain Netals and Alloys in Mercury. (Second Paper.) By W. J . HUXPHRXYS . . 1679 CSV1.-The Identity of Dextrose from Different Sources, with Special Reference to the Cnpric Oxide R:.duciug Power. By CORNELICS O’SULLIVAS, F. KS., and ARTHUR LANDAUICE STERN, D.Sc. . . 1691 By WILL~AX JACKSOK POPE . . , . I . . 1696 AUGUSTUS EDWARD DIXON, M.D. . . 1593 FREDERICK CROSS, EDWARD JOHN BEVAN, and CLAUD SMITH . 1604 M.D., F.R.S., and TAMRMASA HAGA, D.Sc. (Japaiij, F.C.S. . 1610 F.R.S., and TAMEMASA HAGA, D.Sc. (Japaii), F.C.S. . . 1629 and TAMEMASA HAGA, D.Sc. (Japan), F.C.S. . , 16.34 CYVI1.-A Compound of Caniphoric acid with Acetone.

ISSN:0368-1645    

DOI:10.1039/CT89669FP001

出版商:RSC    

年代:1896

数据来源: RSC

摘要:

7 II.-The Alkuline Reduction of :~~~ta.rLit)’u)?iline. By RBPHAEL MELDOLA, l!’..R.s., and ERNEST R. ASDREWS. THE azoxy- and azo-compounds formed by the alkaline reduction of the nitrsnilines and their homologues have for some time figured i n patent specifications as sources of polyazo-colouring inat ters, but hitherto little attention has been bestowed on their purely chemical characters. We have for some time past had under investigation the products of the alkaline reduction of metanitraniline, an examination of which was originally undertaken with a view of finding a, con- venient source of meta-azo-compounds.* Various reducing agents were tried under different conditions, and finally sodium stannite was selected as the most conveuient for carrying the reduction to the first stage.We learnt soon after commencing our experiments that Mr. Arthur G. Green had also been working a t the subject, and he was qood enough to commuuicnte to us the particulars of his method of performing the reduction as well as to place a t our disposal speci- mens of the products which he had obtained. For this information, which has been found of great use, we desire a t once to express our thanks to Mr. Green. Dimetadiam idoaeox ybenzene. I n order to prepare this compound, metsnitzmiline (15 grams) is dissolved in boiling water (1 lit,re) and a cold solution of sodium stannite (40 grams pure stannous chloride crystals dissolved in 100 C.C. cold water and mixed with 40 grams of solid sodium hydroxide dissolved i n 300 C.C. cold water) is slowly added to the boiling solu- tion.On allowing the contents of the flask to cool, the azoxy-com- pound separates as a yellow substance, crystallising in needles. In order to purify the compound, i t is collected, washed with water, dis- solved in dilute hydrochloric acid, filtered to remove tarry matter, and the base reprecipitated by ammonia, this operation being re- pented till the substance dissolves in acid without leaving any residue. Further purification can be effected by crystallisation from toluene, dilute alcohol, or boiling water. From toluene, the substance sepa- rntes in large, golden scales, from dilute alcohol in needles, and from water, in which it dissolves only at the boiling temperature, and then * Concurrently with the above reeearch, I had commenced some experiments 011 the production of meta-azo-compounds by the action of nitrosobenzene on suitable ainido-compomids.The work was interrupted owing to the summer vacation, and Mr. Charles Mills has since entered t,he saine field, and has obtaired results similay to mine (Trans., 1895, 67, 925), so that this part of the investigation is omitted jrom the present communication.-R. M.8 MELDOLA AND ANDREW3 : but sparingly, in very slender, yallow needles. The melting point is 14G-148". A very large number of analyses of various preparations have served t o convince us that the alkaline reduction of metani- traniline is accompanied by the formation of products other than the simple azo- and azoxy-compounds. The azo-compound is, no doubt, simultaneously formed in varying quantities, and its production is unavoidable unless the proportions of sodium stnnnite and metani- trnniline mentioned are rigidly adhered to : but, i n addition, other compounds containing a higher percentage of carbon are also appa- rently produced, and become associated with the basic products.We liavc not been able to isolate any othcr compound a t present, but thc great difficulty which we have experienced i n obtaining specimexis giving correct numbers on analysis has convinced us of the existence of such secondary products. The following resnlts were given by two of the purest preparations. 0.1098 gave 0-2554 CO, a,nd 0.0534 H,O. 0.1216 ,, 24.5 C.C. moist nitrogen at 10" and 765 mm. N = 24.26. 0.1610 ,, 34.3 ,, ,, 15.5' and 755% mm. N = 24.71.C,,H,,N,O requires C = 63.15; H = 5.26; N = 24.56 per cent. The constitution of the compound is expressed by one of the two C = 63.38 ; H = 5.37. formub- I t is a strong base dissolving readily in all mineral acids and in the stronger organic acids ; most characteristic is the insolubility of the dibydrochloride, ClzHlzN40,2HC1, in excess of hydrochloric acid, the salt being at once precipitated in the form of a, whitish, crystalline powder on adding strong acid to the solution of the base in dilute acid. The base dissolres more or less readily in all the usual or- ganic solvents, its solutions being orange ; i t is n o t volatile in steam to a sufficient extent t o enable it to be purified by this means. Of its derivatives, Mixter has prepared the dibenzoyl compound by re- ducing benzoylmetnnitranilide with zinc and alcoholic ammonia ( R m t ~ .Chem. J., 1883, 5, 5 ) , and gives the melting point as about 272". We have prepared the diacetyl derivative by boiling the base for about half an hour with acetic anhydride in acetic acid solution, and crgstallising the product from boiling glacial acetic acid, in which it dissolves but sparingly. I t forms an ochreous powder consisting of micro-crystalline nodules melting at 254". 0.1161 gave 0.2626 CO, and 0.0566 H,O. C = 61.67 ; H = 5.34. 09638 ,, 39.3 C.C. moist nitrogen at 11" and 766.7 mm. N = 17-89.THE ALKALINE REDUCTION OF METANITRANILINE. 9 The bisazimide was also prepared by diazotising i n hydrochloric acid solution, precipitating the diazoperbromide and treating the latter with ammonia (Meldola and Hawkins, Proc., 8, 133).After crjstallisation from petroleum, it was obtaineci in the form of nodular, oclireous crysta,ls, which become darker on exposure to light. 0,1792 gave 62.1 C.C. moist nitrogen at 15.5' and 753.5 mm. N = 40.09. 0.0888 ,, 29.9 ,, ,, ,, 13' ,, 763.1 ,, N = 39.88. N* C ,H4*N3 requires N = 40.0 per cent. O<k.C,H,.N, This compound melts at 85-86', and explodes when heated in a dry tube above its melting point. The yield is not good, as the bisazimide is ccntaminated with a considerable quantity of i l resinous compound, from which it must be separated by extraction with hot, dilute :dcohol, preferably with the addition of animal charwal, before it is in a condition for crystallisation from petroleum.Thc diamidoazoxg-compound is very readily diazotised by the usual methods, and the tetrazo-salts enter at once into combination with amines and phenols to form colouring matters. As a typical azo-compound, that, produced by combination with P-naphthol mas prepared for analysis. The tetrazo-chloride is prepared in the usual way, and the solution mixed with the necessary quantity of p-naph- thol, freshly precipitated by acid from its solution in alkali and suspended as a pulp in the liquid ; uo colour appears at first, but on gradually making the mixture alkaline wilh ammonia, a red tint develops, and, after some hours, st brilliant red precipitate of the azo- colouring matter is formed. The substance, after being collected, washed, and dried, mas purified by repeated cry stallisation from boilicg aniline ; it then formed small, dull, red needles melting at 244-245O.0.1167 gave 15.3 C.C. moist nitrogen at 21.4" and i64.2 mm. N = 15-67. 0.1104 ,, 14.5 ,, ,, 12.75" ,, 766.1 ,, N = 15.64. 0.1015 ,, 0.2665 CO, and 0.0423 H,O. C = 71.GI ; H = 4.63. H = 4.09 per cent. The azo-compound dissolves in strong sulphuric acid with a magenta-red colour, and is precipitated unchanged on dilution with water. I n order to connect the diamidoazoxybenzene with a known com- pound of the same type prepared by another method, a specimen was diazotked, and the amido-groups replaced by iodine by treaking the tetrazo-sulphate with potassium iodide. Much resin was formed,10 MELDOLA AND -4XDREWS : b u t the product, when extracted with alcohol, furnished a crystalline compound consisting of ochreous needles melting a t 118-119*, and having the composition of diiodoazoxybenzeiie. Oa117O gave 6.7 C.C.moist nitrogen at 18' and 753.4 mm. N = 6.61. 0.1426 ,, 0.1476 AgI. I = 55.92. - N-C6H41 requires N = 6%; I = 56.35 per cent. '<kgc6H41 This compound is probably identical with that obtained by Gabi-iel by reducing nietaiodonitrobenzene with alcoholic potassium hydroxide (Ber., 1876, 9, 1408). Di*metadiam idoazo benzene. After many experimeuts with an increased quantity of sodium stannite under various conditions, we finally abandoned this reducing agent as a means of passing from the aeoxy- to the azo-compound. It has been found more advantageous to use for this purpose zinc dust and sodium hydroxide in the following way.The azoxr-compound is dissolved in a small quantity of alcohol, and an equal weight of sodium hydroxide dissolved in a little water is added to the alcoholic solution contained in a flask. A quantity of zinc dust, about twice the weight of the azoxy-compound, is then added, and the contents of the flask kept warm on a water bath for some hours, with frequent agitation ; the solution gradually becomes decolorised, owing to the formation of a hydrazo-compound ; when this stage is. reached, the solution is a t once filtered to remove the excess of zinc, and on exposure to the sir for a few hours the hydrazo- compound is completely oxidised and the uzo-compound regenerated, as indicated by the orange colour of the solution. By this means only can the complete reduction of the azoxy-compound be insured.Potassium hydroxide cannot be conveniently used, as this carries the reduction too far, the yield of azo-compouud being small and metrt- phenylenediamine being formed. The purification of the azo-compound is best effected by crystalli- sation from water ; for crystallisation from organic solvents, especially hydrocarbons, has a tendency to render the compound i m p r e , as it appears to be capable of entering into combination with and obsti- nately retaining some of the solvent. The alcoholic solution contain- ing the aeo-compound, prepared in the manner described, is trans- ferred to a flask, diluted with water, and all the alcohol distilled off; the orange-coloured, crystalline residue is collected, washed with cold water, and dissolved in a large volume of water by means of a little hydrochloric acid.The solution of the hydrochloride is then raised to the boiling point, made alkaline with amnionia, and filteredTHE ALKALINE REDUCTlON OF METANITRASILISE. 11 rapidly while still hot; on cooling, the azo-compound separates in dull, orange-coloured needles. This method of purification is more effective than the direct solution of the azo-compound in boiling water, as the crystals wben once formed dissolve with great difli- cnlty; the treatment can be repeated till t.he hot solut<ion passes tbrough the filter without leaving any residue. The readiness with which the azo-compound combines with other substances renders it a matter of considerable difficulty to prepare specimens sufficiently pure for analysis.Until the above method of preparation and puri- fication was adopted, OUT products all gave a percentage of nitrogen below that required by the formula of the azo-compound, and for some time we were under the impression that the treatment of the azoxy- compound with zinc dust and alkali had not removed oxygen, but had effected transformation into an isonieride, possibly stereochcmical. The melting point (after drying a t 110-120°) is 150-151' when pure. 0.0962 gave 21.45 C.C. moist nitrogen a t 14.2" and 768.7 mm. N = 26.27. 0.0479 ,, 10.9 ,, ,, 20' ,, 768.3 ,, N = 26.27. V*CsH,*NH, K\'.C6Hd*NHZ requires N = 26.41 per cent. In order to characterise this compound further, the bisazimide was prepared by the usual method, but the yield is extremely small, and the melting point the same as that of the bisazimide obtained from the azoxy-compound (86"), so the product was not further examined.The diacetyl derivative was prepared by dissolving the base in glacial acetic acid mixed with acetic anhydride, and heating at 100' for an hour. The product was purified by crystallisation from glacial acetic acid, in which it dissolves somewhat more readily than the cor- responding diacetylazoxy -compound, but as the analytical results still indicated that an impurity was present, it was finally obtained pure by crystallisation from boiling aniline. 0.0952 gave 14-15 C.C. moist nitrogen a t 20Oand 759.5 mm. N = 18-96. 0.1992 ,, 0.4753 CO, and 0.0959 H,O. C = 65.08. H = 5.34. 0.0865 ,, 14.5 ,, 9 9 ,, 21° ), 759.4 ,, N = 19.05.requires N = 18-92 ; C = 64.86 ; H = 5.40 p. c. E*C6H*.NH*C,H,O N* C GH,*NH*CoH30 This acetyl derivative is rery similar in appearance and properties to that obtained from the diarnidoazoxy-compound; it forms a micro-crystalline powder (small needles from aniline) of a somewhat more orange colour than the latter acetyl deriviit8ive. It begins to shrink at 268", and melts completely at 272". The dibenzoyl derivative was prepared hg snspending the crystal-12 RIELDOLA AXD ANDREW'S : line base in warm water, adding the calculated qnantity of benzoyl chloride, and then agitating briskly with the gradual additioa of sodium hydroxide till the solution had become slightly alkaline. The prodnct was collected, washed, and dried, and then crgstallised from boiling aniline.It forms straw-coloured, microscopic needles, melting at 284-285". 0.1587 gave 16.35 C.C. moist nitrogen at 20.5' and 756 mm. N = 13.36. - - R* C 6HPaNH*C7H6O N* C6H,*NH*C7H,O requires N = 13.33 per cent. The diamidoazo-compound is converted by nitrous acid, i n the presence of hydrochloric acid, into w teti-azo-chloride, with the same facility t h a t the diamidoazoxy-compound undergoes this transforma- tion. Combination with [j-naphthol was effected in the same manner as with the previous compound. The trisazo-compound, after crys- tallisation from aniline, consists of small, red needles, duller in shade than the corresponding bisazo-azoxy-compound. 0.1405 gave 19 C.C. moist nitrogen a t 10.3" and 75-53 mm.N = 16.05. 0.0881 ,, 0.2380 CO, and 0.0395 H30. C = 73.68; H = 4-98. H = 4.21 per cent. The substance meIts at 282O, and dissolves in strong sulphuric acid with a magenta colour, which is perceptibly bluer than the colonr given by the corresponding azoxy-compound, the difference bet ween the two becoming more pronounced on diluting with a little water. Like all the azo-derivatives of /3-naphthol, it is destitute of phenolic characters, being quite insoluble i n boiling aqueous alkali. It dis- solves in boiling alcoholic potash with a red coloration, which is indistinguishable from that given by the azosy-compound under the same conditions. Of the salts of dimetadiamidoazobenzene, the oxalate is very cha- mcteristic. I t is formed by adding a solution of oxalic acid to a boiling aqueous solution of the base; the salt separates at once in the form of ochreous scales, which are but slightly soluble, even in hot water.The dry salt has no definite melting point, b u t chars at 205--210'. A specimen dried at ordinary temperatures over strong sulphuric acid i n a desiccator for some days was analysed with the f ol lo wing results . 0.1502 gave 0,3050 COz and 0.0626 H20. 0.1064 ,, C = 55.38 ; H = 4.63. 16.5 C.C. moist nitrogen a t 15Oand 765 mm. N =: 18.29.THE ALRALIXE REDUCTION O F 3IETA"IRASlLINE. 13 From its mode of formation, the diamidoazo-compound may be represented as having the constitution This was confirmed by displacing the NH,-groups by iodine by means of the diazo-reaction. The diiodoazobenzene crystnllises ji; orange scales melting at 150-151° (Gabriel, B e y ., l 8 i 6 , 9, 1410), and is identical with the compound produced by the alkaline reduc- tion of metauitroiodabenzene. 0.0718 gave 4 C.C. moist nitrogen at 10.5O and '758.3 mm. N = 6.61. C,H41*N,*C6H41 requires N = 6.45 per cent. As tlie para-position with respect to the azo-group is open in both benzene rings in the above formula, it appeared of interest t o t1-S whether one molecnle of the compound would combine 1vit.h two molecules of a diazo-salt, so as to form a tertiaryazo-compound of the It was found, liomever, that the base did not combine with diazo- benzene chloride, so a more acid diazo-salt, namely, paranitrodiaao- benzene chloride was used ; combination took place with this diazo- salt in the pi*esence of sodium acetate, and a brown, amorphous substance separated.The latter has all the properties of a diazoamide and not of an azo-compound ; it dissolves readily in alcoholic sodium hydroxide in the cold with rz magenta colour, and with a similar colour in hot aqueous, caustic soda solution ; i t is reprecipituted from its alkaline solutions as a flocculent, ochreous substance on the addition of acids. The compound is uncrystallisable, and could not therefore be obtained pure; it melts with decomposition a t about 198-200"- A determination of nitrogen gave results agreeing fairly Fell with the formula of the bisdiazoamide. ( p ) NO2*C6H4*N2*NH* C6HioN2*CsH~'NH*N**C6HI*T\TOa ( p ) . We have no doubt that this is the compound formed under the conditions described.Il'emarks on the Beduction cf I\li'tyo-coinpotsnds. By R. 35ELDOL-4. The extreme readiness with which meta- and para-nitranilinc* give azox5- and azo-compounds under the influence of alkaline reducing- * Orthonitraiiiline does not give an azoxy-compound when reduced with sodium stannite under the same conditions as metanitrariiline j it is partly reduced to orthophenylenediamine and partly left unchanged.14 MELDOLA: REMARKS ON THE agents, whilst passing with equal readiness into the respqctive diamines under the influence of acid reducing agents, has always appeared to me one of the most striking examples of the difference in behariour of nitro-compounds, according to the mode of reduction, that is, acid or alkaline. In dealing with the theory of the reduction of nitro-compounds the equations X.NO2 + 3Hz = X*NH, + 2820 can obviously be considered only as expressing the 6nal I-esults of a series of intermediate transformations.Of the nature of these in- termediate stages, nothing was known definitely till E. Hoff mann and Victor Meyer showed that nitro-compound8 of the parafin series gave hydroxylamiue derivatives on reduction with stannous chloride ( Rer., 1891, 24, 3528 ; methylh~droxylamine from iiitrornethane). The remarkable discovery by Bamberger (Ber., 1894, 27, 1347 and l.548), and Wohl (ibid., 1432) that nitrobenzene can be reduced to p-pheuylh~droxylamine by zinc dust and water, may be taken as another proof that the mechanism of the process of reductiou is not Amply yepresented by the withdrawal of oxygen from the uitro- qroup.The remarks which I now 7:enture to offer are t o be regarded in the light of a tentative contribution to the theoretical side of this cinestion. Much more experimental evidence will be required before ;L complete theory of t4he process can be formed, but it appears desir- able to call attention at once to the necessity of remodelling the cxisting crude notions respecting a transformation of such general scientific and technical importance. The following attempt to indi- cate, at least, a possible series of steps may be found sufficiently suggestive to prompt further investigation, even if destined to be displaced by other hypotheses as our knowledge grows. Under all conditions, the first action of the reducing agent may be regarded as being the hgdroxylation of the nitro-group.The derivative of the hypot.hetica1 dihydroxylamine being too un- stable to exist, is reduced by further action, thus- O H H X - N < ~ ~ + = X*N< + H,O .. .. .. . . .. (Ir) OH At low temperatures, 2nd with ,weak reducing agents, tho hydroxyl-REDUCTIOK OF NITRO-COMPOUNDS. 15 amine stage can be retained as a resting stage in certain cases. At high temperatures, a i d with strong reducing agents, the second hydroxyl group is replaced. H H X*N < OH + = X*N<H + H,O .......... (111) This view would represent the ordinary conversion of a nitro- compound into an aniine by the usual zethods; it assumes that the hydroxylamine stage is passed through rapidly and imperceptibly, unless special means are taken for arresting the process at that stage.Under other conditions, of which the presence of alkali appears to be the most favourable, and, in a less degree, the access of atmospheric oxygen (Baurberger, Zoc. cit., 1550), the hydrovylamine derivative undergoes " condensation " with the formation of an azoxy- or an azo-compound. To bring about this result two molecules must coalesce, and frQm general considerations concerning such processes of condensation it seems feasible to represent the change, thug- X*N<; ........................... >N*X = H ? 7 + H,O .... (IV) 09 H - iH + HOi X*N--N*X ___-I - ................ The intermediate compound at khis stage would be a derivative of the (at present) hypothetical hydroxy-hydrazine, H,N*NH*OH. The assumption that such a compound is formed harmonises well with the facts, because both the azoxy- and the azo-type are derivable there- from, the former by oxidation and the latter by a repetition of the " condensing " process.These two possibilities are best considered separately. In the first place, the oxidation of such a compound would give rise to an azoxy-compound ; unattacked nitro-compound would act as oxidising agent, or, when all the nitro-compound is re- duced to Stage I (see equation), atmospheric oxjgeii might be effec- tive, as found by Bamberger. HO X*r'oH + ?>N*X = x'r>O + HO>N*X.. .... (V) X*N*H 0 X*N I n the next place, the further (inner) condensation of the hydroxy- hydrazine derivative would give rise to an azo-compound which, from this point of view, is the inner anhydride of its geuerator- (VI) X*T*OH - X*N X*NH X*N - 1 1 + H20 ................The hypot'hesis thus suggests that azoxy-compoands arise, not by direct reduction of nitro-compounds, but by the oxidation of inter- mediate hydroxy-hydrazines-as long as nnaltered nitro-compound is present the azoxy-compound can be continuously formed. No azo. compound could be formed at this stage because the oxidising action16 REMARKS ON THE REDUCTION OF NITRO-COMPOUNDS. on the hSrlroxy-hSdrazine is greater than the tendency to condense to the azo-stage (Equation V). But, when all the nitro-compound is used up, the formation of azoxy-compound has reached its maximum, and the reducing agent can act directly, while condensation to the am-stage can also take place.The question thus arises as to the action of the reducing agent when the azoxy-stage has reached i t s maximum. It seems to me that the dircct removal OF oxygen is again an improbable explanation. The most likely product is the inter- mediate hydroxy-hydrazine. X-N H X-P;T.OH X*N X*NH r>O + & = .... .. .... . I . (VII) As no oxidising agent is present a t this stage, the azo-condez?sation (Equation VI) can now go on continuously. These suggestions are well worthy, as I venture to think, of being submit$ted to the crucial test of experiment ; certainly they are it1 harmony with the well-known fact that the azo-compounds are only obtained by alkaline reduction, as the last stage (unless the reduction be carried on to the hydrazo-stage) of a protracted operation.It appears desirable to reinvestigate in the light of the present hypothe- rjis the pr0duct.s of the reduction of azoxy-compounds, and also to ascertain whether the exclusion of air during the process of alkalitic reduction would accelerate the production of azo-compounds. These and other collateral points snggested in the course of this theoretical discussion will be dealt with experimentally in the course of the pre- sent session. An alternative series of stages from the hydroxylamine derivative (Equation 11) may also altered nitro-compound fol loving way. be suggested. The oxidising action might be regarded as taking place of un- in the XY-OH X*N X-N-OH X-N = l > O + H,O The azoxy-compounds on tihis view also are anhydrides of inter- mediate compounds, namely, derivatives of dihydroxy-hydrazine. The action o f mild oxidising agents (atmospheric oxygen) does convert phenylhydroxylamine into azoxybenzene, whilst strong oxidisers con- vert i t into nitrosobenzene (Bamberger and Wohl). Tn harmony, likewise, with this view is the fact that bydroxylamine itself, under the influence of oxidising agents, evolves nitrous oxide, a decom- position which mamy be brought into line with the above hypothesis.THE CHEMXSTLiY OF DlBROJIOPROPTLT~IOCARBI~ilDE. 1 7 The p~ototype of the azoxy-compounds is thus nitrous oxide or its From this point, ~lihydro-clel.irstive, wliicli is a t present unknown. of view tho generally accepted formula of the azoxy-compounds is correspondi ug to St recker's preferable to the Eormula X*?p*X, 0 formula f o r the dinzoainides. Another point, in favour of some such view of the course of reduction of nitro-compounds, as is here advo- cated, is that it gives promincnce to the analogy with thc process O E d u c t i o n of nitroso- and isonitroso-coinpounds. ,<,;.OH 3 x<oH XH-OH - .x<;:p It is unncccssary t,o elaborate these suggestions froin the specula- tive side in greater detail at present, but it will appear from the foregoing that such an apparently simple change as the conversion of a nitro-compound into an amine is by no means so well understood as the crude equations generally given wonld lead us to suppose.

ISSN:0368-1645    

DOI:10.1039/CT8966900007

出版商:RSC    

年代:1896

数据来源: RSC

摘要:

THE CHEMXSTLiY OF DlBROJIOPROPTLT~IOCARBI3llDE. 1 7 I II.--.Yhe Chemistry of Uibromo~~1.opyltl~iocal.bimide : and the Actioiz o f Bronzi.lze and of Iodine up011 A I1 y It I b i o ~ e a . By AUGUSTUS E. DIXOS, M.D. 13 a short communication, made a few years ago to this Society (Trans., 1892, 61, 545), I showed that bromine unites readily with ally1 thiocarb imi de, thereby prodncing per- dibromopropylthiocar- bimide, CH2Bi-CHBr.CH,.NCS, a dense, almost colourless oil, of high refractive power., volatile i n a current of steam, nearly insoluble in water, miscible with alcohol, possessing thc characteristic odmr, and, generally speaking, the ordinary properties of a liquid thiocar- himide. In its chemical :.elations, however, it manifested certain peculiari- ties; thus, for example, it combined readily, on warming, with aniline, but instead of affording the expected dibromopropylphenyl- thiocarbarnide, CH,Br*CHBr*CH,.NH.CS.NH.CsH,CH, 1 mol.HBr was eliminated, the product being the hjdrobromide of a closed chain basic coniponnd, from mhich the frce base, a solid, was liberated by TOL. LXIX. c18 DIXON : THE CHEMISTRY treatment with caustic alkali. mentioned, the action was believed to occur, ultimately, as follows. For reasons set fort,h in the payer Further, the thiocarbimide interacted spontaneously with alcoholic ammonia, but instead of di bromopropylthiourea, ammonium bromide was obtained, together with a viscid, basic syrup, which refused to crystallisc, and was not then further examined. That the aotistitiients in question should fail to afford dibromo- propylthiourea, was, at the time, a matter of surprise, especially as the latter compound appeared, on reference t o Beilstein’s Handbuch,* to have been already prepared and examined by Maly, who obtained (Zeit.f. Chem., 1867, 42), from bromine and allglthioures, a welt- defined solid substance, C4H,N2SBr = ? CSNzH3*CH2-CHBr*CH2Br. Returning later, however, t o the study of this and similar com- pounds, their properties seemed hardly to accord with tho above con- stitution ; thus, according to Maly, the dibromide, C4H8N,S,Brz, when treated with moist# silver chloride, exchaaged but 1 atom of bromine for chlorine, producing the chlorobromide, C4H8N,S,BrCl ; again, with moist silver oxide, a strongly alkaline hydroxybromide, C4H8N28,Br( OH), was formed, from which, b y the action of hydrochloric acid, the chlorobromide was regenerated.Maly did not, fail to notice the significance of these peculiarities, for he refers expressly to the special fnnction of one bromine atom, which acts like the bromine in ammonium bromide;? in the case of tlre chlorobromide, the chlorine atom plays an analogous part. Moreover, further experiments on the interaction of alnmonia w i t h dibromopropylthiocarbimide suggested the desirability of re- examining the dibromo-derivative ; and this has now been done, with results leading to the conclusion that it and the other allied sub- stances (including a di-iodide) arc not halogenised thionreas, but salts of basic riug-compounds, derived probably from the parent- f Unfortunate!y I had not then access to the original paper.t “ Giebt man dem Thiosinnaminbromur folgende Formel : C H 5Br}N,Br *H in der ein Atom Broin das eine Ammoniak ZIII’U Ammonium rnacht, also innerhalb drs Radicals st,eht, wahrend dss zweite die Stelle einnimmt, wie das Brom im Broniammonium, oder das Chlor im Salmiak, so ist wold zu erwarten, dass sich diese beiden Bromatome rerschieden verhalten werden ” (Zoc. cit.).OF DIBROMOPROPYLTHIOCARBIMIDE. 19 t'ype, CH,< CH*S cHl,N>C*NH2, that is, p-amidopenthiazoline, or, using the nomenclature proposed by me (Trans., 1895: 67, 564), tri- methylene-pn- thiourea. B R O M J N E A N D ALLPLTHIOUREA. The addition Pl-Gduct, ClH8N2S,Br2, was prepared by adding 1 mol. of bromine, dissolved in chloroform, to allylthiourea (1 mol.) in alcohol ; cooling by means of a freezing mixture had little influence on the yield, which amounted, in one case, where it was employed, to 72i per cent.of the theoretical, and i n another, where it was not, to 71 per cent. After removing all the solid matter, a residue was obtained, consisting of a rather dark brown syrup. which, at, the temperature of the water bath, evolved fumes of hydrogen bromide. The solid product deposited slowly ; it was, as described by Malg, soluble in water and alcohol, very easily in the foimer, more sparingly in the latter; in other solvents, it was in- soluble, o r nearly so. Its melting point fell somewhat below that given, namely 146--14i0 ; I observed in two succeshive prcLparations 1:39-140" and 139*5-140-5° (con-.), respectively, apparently with- out decomposition.The aqueous solution had an acid reaction, was not desulphurised by tre;ttrnent with alkaline lead tartrate, and yielded with ammonia- cal nitrate of silver a whitish precipitate (not readily affe-ted by exposure to sunlight), which did not blacken even on boiling the mixture. Presumably, therefore, the cornpound was not a mono- substituted thiourea (Dixon, Trans., 1893, 63, 319). Actiorr qf Caustic Alkali.-On the addition of strong caustic potash (or even ammonia) to the aqueous solution, a heavy basic oil was. precipitated, containing nitrogen, sulphur, and bromine. The super- natant clear liquid, when acidified and treated with chlorine water, reacted freely for bromine ; inoreover, with silver nitrate, it gave i t yellowish precipitate of silver bromide.Thus a partition of the bromine had occurred, a probable explanation of which, in view of the above phenomena, lay in the abstraction by tbe alkali, from the original substance, of a mol. of hydrogen bromide- C,H,N,SBr, - HBii = CIH,N,SBr; and the results of a roughly quantitative experiment went to support, this idea ; 5.1 grams of the dibrominated compound yielding nearly 3.5 grams of basic oil, whilst, according to the equation, 3.6 grams should have been obtained. The oil is clear, almost colourless, iiiiscible with spirit, soluble in c 220 DIXON : T€IE CHEMISTRY niucli cold water, or moderately at the boiling temperstare ; it is strongly alkaline t o litmus, has a barely Ferceptible basic odonr, and when dissolved in dilute hydrochloric acid, reacts freely with clllo- rine water for bromine.If exposed for some time to air, i t darkens, becomes hard, and insoluble in spirit ; i t dissolres now only slowly in boiling hydrochloric acid, from which i t is precipitated hy alkali as an amorphous, whit3ish powder ; t h e latter, on heating, swells up and carbonises without melting ; it appears also t o be insoluble, save in liquids which decompose it,. The nature cf tliese latter changes mas not investigated. Actioiz of IIych-oLronzic ucid.-Dilnt e hydrobromic acid was added i n slight excess, to LZ qiiantity of the freshly precipitated base; t h e mixture wzs at first turbid, but became clear a s t h e point of neutra- lisation was approached ; t h e solution was then evaporated to a, snialI bnlk on t h e x-xter bath, and left orerniglit ; wliite c r p t d s sepa- rated, freely soluble in water, l m r i v g t h e appeamncc, and exhibiting d l t h e properties, of the compound cbtained hy t h e direct union of lxomiiie with allylthionrea, and me1 ting, after i~eci~ystnllisation, at the same temperature, namely, 139-1-lOG.Action of Hydrochloric ncid.-IIf, then, Maly ’s alIylthiourea di- bromide is t h e hydrobromide of a base, C4HiN,SBr, t h e latter, on treatment with hydrochloric acid, ought t o afford a hydrochloride, C4H7N2SBr,HC1, identical with t h e clilorobromide obtained b y him from tlie dibromide and moist silver chloride. “his is, in fact, the case, as shown by the following experiment. A quantity of‘ t h e basic oil was treated with a slight excess of hydrochloric acid, and the clear solution concentrated by evapora- tion on the water bath ; on cooling, beautiful I-osettes of long, very hard, white prisms were deposited, having t h e properties ascribed to t h e chlcrobromide, and me1 ting, after being prei-iouslv well washed with spirit, a t the temperature recorded by MaIy, namely 129-130”.This compound, like tlie hjdrobromide itself, reacts freely for bromine 011 the addition of chlorine water. From this sjuthesis, i t may be concluded t h a t the hingle bromine atom which the ‘. dibro- mide ” gives u p 011 treatment withmoist silver chloride is t h e one not included in t h e C,H7N2SBr fraction of t h e molecule. It seemed of interest to t r y whether dibromopropylthiocnrbimide would exchange any of its bromine for chlorine under t h e abovc treatment ; an experiment was therefore made by allowing the tbio- carbimide, in aqueous spirit, t o remain (in the dark) in contact wit11 excess of freshly precipitated silver chloride, shaking frequently.After 10 days, during which interval slight desulphurisation bad occurred, t h e mixture \\-as heated for a, few minutes, and then steam distilled j a brilliant oil mine over, i n which the sulphur and nitrogenOF DIBROMOPROPYLTHIOCARBIhI1I)E. 21 were determined, with the result that it proved to be the unchanged dibromopropyl tliiocnrbimide. Actlo77 of Pic& acid.-In order to obtain the base in a form which admitted OF easy purification for analysis, i t was converted into the picrate, either by treating the liquid base in alcoliolic solution with picric acid, o r by adding the latter to an aqueous solution of the hydrobromide, got from bromine and allylthiourea.In either case, a finely d i d ed, canary-yellow precipitate fell, which, on recrystalli- sation froni dilute spirit, was obtained in miii~ite, glitteriiig, pale- yellow prisms, melting a t 187-188" (corr.). If heated rapidly over a gas flame, it melts, begins to effervesce, and then deflagrates, leaving a porous, carbonised residue. The picrate is rather sparingly soluble in boiling water, still less so in cold ; more easily, though by no means freely, in boiling alcohol^ 1 t is oxidised by boiling with nitro-hydrocliloric acid, with formation of sulphuric acid, but yields no sulphur to boiling alkaline, lead, 01- silver solutions.The formula was checked by analysis. 0*2017gave 0.2074 CO,, and 0.0365 H,O. 0.2074 ,, 29.4 C.C. nioist nitrogen at 15" and 759 mm. N = 16.59. C,H,ilr',SBr,C6H2(?\T0.?)3*OH requires C = 28 23 ; I3 = 2.36 ; C = 28.04; H = 3.11. 0.2992 ,, 0.168:3 BnS04. S = d.43. ,-' N = 16.55 ; S = 7-55 per cent. These figures-although that for the hjdrogen is unduly high- sufice t o establish the composition of the base as CIHiN,SBr, and not C4E8X2SBr(OH) ; the latter, Maly's b~o~~~tl~iosinr~anznzol.liumoxyd- hydmt, would requirc C = 27.13 ; H = 2-26 ; N = 15 88 ; S = 7-25. The percentage composition of this compound differs only slightly from that of tho base C,YiN,SBr (even assuming them both to be uncombined), and i t seems not unlikely that the material analysed';' by him was the base in question, possibly containing moisture, or else sliglitly impure.A 111 inowia a nil Dib9-omopropy Ithioca 14 imicle. The chcinistry of the iiiteract,ion between allylthioures and bro- mine laving been hhus far cleared up, an investigation of that between ammonia and dilro~noprop~l thiocarbirnide was now pro- ceeded with. Previous experiment had, as already stated, established the non-formation from t!iesc constituents of dibromopropylthiourea ; but the facts which Lad meanwhile come t o light pointed to such a iiegative result as at leasf probable, for the union of the compounds in question might be expected t o result in the production of the hydro- * No analysis is givcn in liis paper.22 DIXON : THE CHEMrSTRY bromide of the brominnted base, and since this salt is decomposed by ammonia, as shown above, the prodiicts to be anticipated are those which were actually obtained, namely, a basic oil, together with ammonium bromide, C,H,Br,*NCS + 2NH3 = NH4Rr + C4H,N,SBr.Dibromopropylthiocarbimide was dissolved in a considerable excess of strong alcoholic ammonia ; interaction commenced in a few seconds, with evolution of so much heat that the mixture began to boil, and, on cooling, crystals of ammonium bromide were deposited. When evaporated a5 F t r as possible on the water-bath, the product con- sisted of a brownish oil, mixed with solid matter ; this was treated with excess of dilute hy(lrobromic acid, again evaporated, and ex- tracted with absolute alcohol, which left most O F the ammoniuni hvomide undissolved, and by repeating the evaporation and extraction, x little more ammonium bromide wag removed.The clear solution as then mixed with a few drops more of dilute hydrobromic acid, arid allowed to evaporate spontaiieously; next day a crop of solid matter had formed, entangled in a tenacious mother liquor ; the latter was drained off, not without difficulty, by aid of the pump, and the residue recrystallised from water, and well washed with spirit. The product was colourless, freely soluble in water, soluble in alcohol, had nn Acid reaction, gave, on the atdtlition of caustic potash, a basic oil, afforded bromine when treated with chlorine water, and in short,, resembled precisely the hydrobromide obtained from allylt,hiourea ; its melting point was 139-140' (corr.), that is, identical with that observed for the said hydrobromide.For further identification, the thiocarbimide and ammonia were combined as before, the precipitated ammonium bromide was dis- solved by adding water, and the oil by dilute hydrochloric acid ; the clear solution, when mixed with caustic alkali, deposited a basic oil, which w-as dissolved in spirit and a little hydrochloric acid, and treated with picric acid. It gave a somewhat viscid, yellow prccipi- tate, which, after recrystal lisa,tion, had the appearance and general properties of the picrate already descx-ibed, melting at nearly the same temperature, namely, 183-184" (corr.). Summarising the principal facts elicited from the above experi- ments, it may be statcd tliat- 1.Bromine unites directly with allylthiorirea to form R compound, C,H,N,SBr, ; this compound is the hydrobromide of a strong base, C,H,N,SBr, which is liberated from it as an oil on the addition of caustic alkali. 2. The free base combines with hydrobroniic, hydrochloric, and picric acids, yielding C4H,N2SR r,HB r, CIHiN2SB r, HCI, and C4H7N,SBr,CsH,( NO,),*OH,OF DIBROMOPROPTLTHIOCARBIMIDE. 28 respectively. The first of these is identical with the addition product of alljlthionrea and bromine. 3. The same base, 'together with ammonium hromide, is formed by t8he action of alcoholic ammonia on dibromopropylthiocarbitnide. Constitution of f he Base, C,H,N,SBr.-The mechanism by which the above base is produced niay be explained as follows.First, having regard t o the very favourable conditions realised for its formakion, the initial stage consists, probably, in the production of (an unstable) dibromopropylthiourea ; and since the mono-substituted thioureas, a t all events when undergoing chemical change, and parti- cularly under the influence of substances containing halogen, assume generally the '' labile " form, the base may be supposed t o originate from the decomposition of either C31T,Brz*N:C( SH)*NH,, or C3H,Brz*NH*C (SH):NH. Secondly, the tenacity with which the base retains its sulphur, not only on treatment with alkaline lead solution, but even aft-er boiling with the much more potent ammoniacnl silver nitrate, points strongly to the existence of a sulphur atom, held in closed chain between two other polyvalent atoms.Such a linkage would necessarily entail the withdrawal of the SH hydrogen (to form hydro- gen bromide), and the action would then occur in one of the two following ways, probably the former. CH,* S 1. CHBr<CH CHzBr H,s,>C*NH, = HBr + CHBr<CH2.N>C*NH,; 2. CHBr<CH,---NH>C:NH CH,Br HS = HBr + CHBr<C,H,"ZG:>C:NH; 2-- wit.h, of course, the alternative possibility that the bromine in the @position might be removed instead, for example, CBzBr*FHBr HS CH,Bi.*$lH S CHZ - N CH,.A >C*NH, = HBr + ,>C*NHp Moreover, these structures accord much better with the highly basic cliaracter of the substance than those where the SH is supposed to persist, for instance, CHB~<:&~YC.SH. Other evidence of a more direct kind goes to confirm the views above stated.By combining methylthiocarbimide with hromethyl- amine, Gabriel obtained (Ber., 1889, 22, 1148), not methyl. brom- ethylthiocarbimide, CH3.NH.CS.NH.C~z.CH,Br, but the hydro- bromide of a bme, " n-metByl-ethylene-+-thiourea," * In tbe same paper, he conjectures (p. 1145) that Maly's dibromide,24 DiXON : THE CHEMISTRY Hirsch, in like manner, starting from /3-~romopropylamine, pre- pared (Bey., 1890, 23, 971) with methyl and allyltliioc,zl.bimie~, l3Me.S the " propylene " derivatives, CH,--N >C.NIIMc, and >C*NEIAlI, flHDle*S CII, --N respectively ; the structu1.e of these compounds was established by their behaviour on oxidation, the first-named, for example, yielding methylamine, caybonic anhydride, and taurine.YH2* S yHz.S02* OH >C.NHMe + 2H20 + 3 0 = NH,Me + CO, + c H,." C H,.NH, These and other similar experiments by Gabriel and his pupils, have shown the easy mobility of a halogen atom, under the circum- stances mentioned ; whence, by analogy, the general struct,in*e of t h e basic dibromopropylthiocarbimide derivative may be inferred, save as regards the position of its bromine. I t has been pointed out, how- ever, by P a d (Bey., 1891, 24, 4'253) that bromirie is more readily e1imin:ited from the than from the /3-position (see also Andreascb, .Mo.nntsh., 1889, 5, 33) ; t h o constitution of the base is, therefore, presumably CHBr<cH~.N>C.NIIZ,~ CH *S that is, p-anlido-y-bmmopenthi- nzoline. Regarded a s a dihydric thiourea derivative, and marking the points of substitution in the carbon ring, a, /3, pi, reckoning from the nitrogen attachment ( n ) of the latter, its structure niay also be systematically expressed, accoding to the nomenclature referred to above, by the name /3-bromo trimethylene-\1/?~-tliiourea.It was hoped that by reduction of the base with nascent hydrogen, its bromine might undergo replacemciit, and the position of the latter be dircctly ascertained by the production of either triniethylenti- pi= propylene-pseudot hiourca, t h u s cH3'7 '- '>C.NH, ; CH,*PU" >C-NH, + 2H = HBr + CH,Br*$: H - S C H,*N but the methods tried, namely, treatment with sodium amalgam, or with tin and hydrochloric acid, led only t o disruption of the molccule. C,T€,N~SEr,, slioiild be regarded as the Ii~drobrornide of a siinilarly constituted base j I only noticed this statement after practically all tlie work in this paper hod been completed.* Probably capable of interac?ing also, uiicler suitable conditions, in tlie desinotropic form, CEB~<:$.;;>C:XII.OF DIBROMOPROPTLTHIOCARBIMIDE. 25 The readiness with which tho brominnted thiocnrbimide parts with an atom of i t s halogen, thereby forming the balo‘id salt of a base (or fme hydrogen bromide) will be seen from what follows, t o be a s marked with primary and secondary amines (and even with alcohols) as in the case of ammonia ; i t seems, in fact, as though the broininsted thioureas,* mono-, di-, or tri-ecbstituted, are all alike incapable of existence under ordinary conditions.The question arises, therefore, whether, haviiig regard t o the apparent similrtrity of tlie cases t o those above-mentioned, the “ cEilor~l1yltbiouren ’’ and “ bromalljlthiourca,” briefly recorded by Henry (Be?.., 1872, 5, ISS), as resillting froin the action of ammonia on a-chlor- and bt.orn-tlllylthiocsrbimides, respec- tively, are not also halo’id salts, namely, tlie hydrochloride a n d CH,:C -- S hydrobromide of a basic ring compound, (:l12.K>C*NH2. I hope, later on, to re-examine t h c x substn~~ccs. T O D I N E A S D d L L P L T H I O U H E B . By combining the above materials in alcobolic solution, Maly ob- tained (Zeit. j’. Chcm., 1869, 258) almost colourless crystals, soluble i n water and alcohol, l q i n n i n g to ixelt, m-ith decomposition, a t 90°, and consisting of CJ38N2S,T2.Like the corresponding bromo-deri- vative, this diiodide, on treatment with silver chloride, exchanged half its lialogen for clilorine, yielding thereby t h e chloriodide, In repeating t h e former experiment, I added tlic calculated quantity of solid iodine, to allylthiouwn, in alcoholic solntion. Heat was crolved (this was checked by external cooling with water) and the iodine quickly dissolved, yielding a clear, brown so:u tioii ; on conceii- trating, and allowing i t to cool, i t solidified t o a mass of haid. brownish crystals, which when washed with benzene and spirit, became nearly white, and melted a t 136-5-133*5° (corr.) to a reddish liquid. There is so marked a divei3gence between this melting point, and t h a t one given by Maly, t h a t i t was considered ndrisable to check the formula by analjsis ; figui-es, however, were obtnined, agreeing with those required for the diiodo-addition product.C,H,N,S,CII. 0.2036 gave 0-255 AgI, and 0.1262 BsSO,; I = 68-73; S = 8 52. C,H,K2SI, requires I = 68.59 ; and S = 8.66 per cent. The cornpound is readily soluble in water and alcchol, insoluble i n benzene; its aqueous soiution is sharplg acid to litmus, gires t h e reaction f o r iodine, after the addition of chlorine water, and is not * This does not apply to compounds in which the bromine is included in an aromatic ring. A U C ~ as bro~iophen~ltliioui~ea.26 DISON : THE CHEMISTRY desnlphurised, either by ammoniacnl silver, or by alkaline lead salts, even on boiling. Action of Caustic Alkali.-Ten grams of the di-iodide were dissolved in a little water, and the solution mixed with a, slight excess of strong caustic potash a dense, nearly colourless, very tenacious oil at once sank to the bottom.Aftei- a short time, the supernatant liquor was poured off and examioed ; it was found to contain much alkali iodide. The residual oil (washed with water) becnme pasty a t -8', hut did not solidify ; it was very sparingly soluble in water or dilute alkali, insoluble in ether, miscible with a little spirit, readily soluble in hydrochloric acid, strongly alkaline to tcst-paper, and reacted freely for iodine when treated with chlorine water. I n this case, therefore, a s in that of the corresponding bromo-compound, part of the halogen is removed by treatment with cold alkali, and part Left in R basic residue.In order to get the latter in a form fit for analysis, i t was dissolved in dilute hydrochloric acid, and picric acid added to the clear solution. The bright yellow, amorphous precipitate thus prodiiced was collected, well washed with water, and dissolved in boiling alcohol ; on cooling, the solution deposited spherical aggre- gates of orange-yellow, minute prisms, darkening a t 172', and melting, somewhat indistinctly, at 176-177'. If heated more strongly, it turns reddish-black, swells up, and effervesces, evolving violet fumes of iudine. I t is practically insoluble in boiling water ; the alcoholic solution, if mixed m7ith starch a i d chlorine water, and then diluted, gives no blue coloration.S = 6.94 ; I = 26.62. 0*%094 gave 0.1032 AgI and 0.1057 BaS04. The interaction may be thus represented- C ~ H , ~ z S I , ~ ~ H ~ ( ~ ~ ? ) 3 * ~ H requires S = 6-80; I = 26.92 per cent. CSN2H3*CH2*CH:CH2 + 21 = C H I < ~ ~ ~ : ~ > C * N H , , H I , the iodisecl base, accordingly, being p-arnido-y-iodopent biRzolin e, other- wise /%iodotrimethylene-+n-t,hiourea. When the base is tlreated with ammoniacal silver nitrate, a white precipitate forms, which is scarcely coloured, even by expostire to direct sudight. With iodine monobromide interaction occurred, but no bromiodopropyltliio- cmbimide could be obtained. Iodine appears not to combine with allylthiocarbimide. ACTION O F O R G A N I C BASES ON D J B R O M O P R ~ O P Y L T H I O - CARBINITDE. Numerous experiments were made in this direction, using primary and secocdary bases, and phenylhydrazine.Interaction occurredO F DIRROMOPROPPLTHIOCARBIMIDE. 27 ceadily in every instance on warming. but the bases, when liberated irom the corresponding hydrobromides by caustic alkali, were, very frequently, uninvi ting viscid masses, sometimes having the consist- ence of birdlime or pitch, and resisting all the attempts made to get, them into suitable condition for analysis. The cases where deiinite results were attained me recorded below. Dibromopi.r~ylthiocal.bimide and Payatoluidine. These, in molecular proportion, mere separately dissolved in nearly absolute alcohol, the solutions mixed, and the alcohoi driven off on the water bath. The residue, a thick, apparent.ly uncrystallisa\~le, acid syrup, consisting of the hydrobromide, was dissolved in dilute hydrochloric acid, and the clear, yellow solution treated with excess of caustic soda.The yellowish, heavy oil which mas precipitated, i n ft short, time changed to a whitish golid ; the alkaline liqiior poured off from this contained sodium bromide. The solid was twice re- ci-ptallised froiii alcohol, and t,hns obtained in rosettes of pointed, white prisms melting at 124-125' (corr.). hiialysjs gave the following result. 0.2097 afforded 0.1743 BaSO+ S = 11.42. CllHI3N2SBr rcquires S = 11-24 per wnt. The interaction may be thus formulated- CH,Rr.CHBr*CH,-NCS + C,H7.NH2 = CHBr<~~$'>C*NH.C,H: + HBr, the product being, accordingly, p-paratolylamido-(y-bromopcnthiazo- line, or, using the " thiourea " nomenclature, P-bromotrimethylene- ~/n,-v-paratolylthiourea." Tlie substanco is very faintly aikaline t'o test-paper, freely soluble in warm alcohol, much less so in cold, insoluble in water. It is not affected by boiling w i t h alkaline lead solution, and gives, with am- moniacal silver nitrate, a white, amorphous precipitate, which is not blackened by heating the mixture.* Possibly, since thiocarbimide and a monosubstituted basc are here interact- ing, the intermediate formation of a fliiocarlamide, S C < ~ ~ ; ~ ' C H B r ' C H ~ B r , might be anticipated, with subsequent, break-doxn into SC < ~ ~ ~ CHBr and HBr ; but, in the first place, even if a thiocarbamide mwre initially produced, the deformation of its molecule into the " labile " (thiourea) configuration, under Llie iiifluence of the halogen, is to be expected ; and, secondly, a compound having the structure indicated, would almost certaidy give up its sulphur without difficulty t,o rsmmoniad silver nitrate.28 DIXON : THE CI-IElIISTRY After numerous nnsuccessfnl attempts to isolate this CoinpouiicI, the following method was found t o answer.Orthotoluidine and the thiocnrbirnide, in molecular proportion, were dissolved in spirit,, and the mixture slowly evaporated on the water bath, so as to expel most of the solvent. The residue, rz thick, jellow s p u p , was ti-ansferred to :t flask, and distilled with steam until the distillate ceased to be turbid ; the residue in the ff ask, a clear, colourless solntion, mixed with ti-accs of a dark oil, which refused to come over, was separated from the latter by filti.ntion through paper, and the filtrate concen- trated on the water bath.On cooling, the hydrobromide sank as a clear, pale brown oil, wliicli slioxTred no sig~is of solidifying cven after some days' standing. It was then dissolved in a, sufficiency of warm water containing a tracc of spirit (about 30 volumes were required) and caustic potash added ; tlie base was thereapm precipitated as :I paste, which in a short time bncame tongti. I n this condition i t was very freely soluble in boiling sphit, from which. on cooling, it was deposited in well-formed crystals ; after a couple of recr-ystnllisatioiis from the same Eolvent, it formed beautiful, vitreous, apparently rhombic, plates, melting at 13 l.*S-lS5*5O (corr.).0.2039 gave 0.1672 BitSO,. CI,H,,N2SRr requires S = 11.24 per cent. The 01-thotolyl base is feebly alkaline to litmus ; when pure, i t is somewhat sparingly soluble in boiling alcohol, much less so in cold, and issoluble in water. I t s alcoholic solntion, when treated with alkaline lead tartrate, is not desulphurised ; even tlie whitish prccipi- tate, which falls on the addition of ammoniacal silver nitrate, may be boiled without the least sign of darkening. S = 11.27. By evaporating on Lhe water bath mixed alcoholic solutions of di- bromopropylthiocnibimide and p-naplithylamine, tlie hydrobromide was obtained as a tenacious, brownish syrup, difficultly soluble i n cold water. It was dissolved in dilute hydrochloric acid, the solu- tion mixed with excess of caustic alkali, and the lmxipitsted free base, a thick, browii oil, washed with water, arid set aside ; after a few days it solidified, and by repeated recrgstaliisat,ion from spirit, nsing animal cl~arcoal, brilliant, nearly white, prism3 wei-e obtained, softening at 189", and melting between 190 slid 191" (con-.).0,1992 gave 0.1430 BaS04. S = 9-86. C14HlJK2SBr requires S = 9.93 per cent.OF DIBROMOPROPYLTIIIOChRCIM1DE. 29 The base is neutral t o litmus ; slightly soluble in boiling water, easily in boiling alcohol, rather sparinqly in cold ; it is not visibly affected by boiling with alkaline solution oE lead. Ammonincal nitrate of silver precipitates a white, ainorplious substance, not rcadily coloured by exposnre to white light, and not blackened on boiling ; this precipitate is insoluble iii diluto nitric acid.but is decom- posed by the concenbrated acid, with formation oE silver bromide. Operating as iii the precerliilq case, an extremcly viscid brown hydrobromide was obtained, practically insoluble in \I ater ; the base set free from the hydrochloric solution of tEc hydrobromide fornied .z tenacious lmstt', eventually acquiring a pitch-like consistence, i t WAS iris01 uble in water, rniacibl2 with ~ a r ~ i spirit, but (lid n o t crystalliscb from the latter. I n a second espe~irnent, the base was steam-distilled in order t o remove any uncliaiiged thiooarbimide cir nnphthyl,zrnine, but die product, even aEter long keeping, liad solidified to o n l j :L trifling extent.For the pyrpose oE analysis, thc picrate T V ~ S prepared, ancl purified by recrjstallisntion from boiling acetic acid. The rnyrtle- greec prisms which sepnratcd on cooling 7,vere dissolved in hot hydro- chloric acid ; OR pnrlly nentralisinq thc solution, the pic:*ate was thrown down as a bright ydlow powder. S = 5-80. 0.2008 gave O.OS46 BaSOI. C,,H1,N,SBr,C,H2( NO,),*O€€ requires S = 5.82 per ccnt. The base, in alcoholic solution, is not desulphurised by boilinq with alkaline lead iartratc ; on the addition of ammoniacal nitrate of silver a wliite precipitate fulls, not blackened by boiling, but changivg rapidly in sunlight, first to rose colour, and then to deep purple. Dilute nitric acid, added to an alcoholic solution of the base, affords :L rich, but evanescent, purple - bl u e coloration. Interaction occurred spontaneously on adding the thiocarbimide to (:tlcoholic) met,hylanilinc, with evolution of so much heat that the mixture began to boil.The blackish-brown syrup thus obtained ivc2.i treated as described for the corresponding ortliotolyl compoun1,i. After steam-distillation, the filtered residue was of a, pale, clxi-e t colour ; when concentrated and allowed to cool, it solidified t o a slate- coloured, crystalline mass, becoming white 011 mashing with spirit ; by recrystallisation from hot water, small wliite prisms were ob-30 DIXON : THE CHE?clISTRY tained melting at 183-184" (corr.). The hydrobromide is \Terj freely soluble in alcohol aid in hot water, much more sparingly in cold ; the solution has a marked tendency to remain supetwtturatcd. its aqueous solution reacts sharply acid, is not desulphurised by boil- i n g with alkaline lead, or ammoniacal silver salts, and affords bra- mine when treated with chlorine water.0.2001 gave 0.128 RaSO,. S = 8-80. C,,H,,N,SBr,HBr requires S = 8.75 per cent. By mixing the aqueous solution with caustic potash, the base I V ~ S thrown down as a heavy, brownish oil, which did not solidify in R freezing mixture ; i t is insoluble in water, soluble in alcohol, etliei-, benzene, arid hydrochloric acid ; the latter solution gives no reaction for bromine after treatment with chlorine water. Alcoholic silver nitrate precipitates a nearly white silver derivative ; if this be covered with nitric acid, no immediate change takes place, but after a short time sudden and violent actiou occurs with evolution of nitrous fumes, silver bromide being left. CH 9s p- Pipe;.idy 2- y - bromope t I t hiuzoliue , C H B I*< cH-.N> C*N C,H I ,, . From the thiocarbimide, in alcohol, and piperidine : here, as with the other secondary base (nietliylauiline), 1-igorous action spontane- ously occurred, the mixture boiling freely. On cooling, beautiful, anemone-like, crystalline tufts appeared, and the whole inass pre- sently solidified ; the product,, after two rewystnllisatious from boil- ing spirit, formed brilliant, colourl(w, vitreous prisms, freely soluble in hot, but only sparingly in cold, alcohol, and melting at 189-190° (COW.), with previous sintering a t 1 8 8 O . It dissolves also 'in cold water, yielding a solutioii which is ncutml to litmus ; this solution, when treated with chloroform and chlorine water, gives the reaction for bromine.0.2588 gave 0.1792 BaS04. S == 9.51. CSHl,N,SBr,HBr requires S = 9.31 per cent. The aqueous solution is not desulphurised by boiling with alkaline lead tartrate, but becomes clear yellow ; with ammoniacal silver nitrate in excess, a bulky, white precipitate falls ; the lat.ter is very sensitive to light, a rich purple colour developing after a few seconds' exposure in the sun. By adding dilute caustic potash, the free base mas a t once pre- cipitated as a clear, almost colourless, strongly alkaline syrup, iusoluble in water and alkali, soluble in alcohol, ether, and acids ; it contains halogen, as shown by the copper oxide test, but does iiok react for it on treatment with chlorine water.OF DIBROMOPROPYLTHIOCARBiMIDE.31 The alkalinit,y of the piperidyl base is so great as to allow of titra- tion by standard acid ; but on account of its practical insolubility in water, this is best performed indirectly. 0.3828 gram, dissolved in 20 C.C. N/10 HCl, required for neuti-ali- sation, 5.5 C.C. N/10 NaOH, corresponding to 14.5 C.C. acid used up to form the hydrochloride. Theory for C9HljN2SBr,HC1 requires 14.58 C.C. ACTION OF ALCOHOLS ON T H E THIOCARBIMIDE. BibToni qwopylt h.ioca&mide and E th y lic A1 cohol. p - E't hoxy -91- b ~ o ~ n o - This reaction was carried out in the expectation o€ obtaining the penthiazoline. snlphuretted urethane-- Eight grams of thiocarbimide, together with excess of anhydrous ethylic alcohol, were sealed up, and heated for about an hour, at a temperature slightly over 100".On opening the tube, some gas escaped, smelling of mercaptan, and blackening lead paper ; the contents of the tube thereupon partly crystallised. The mother liquor, from which the crystals had sepa,rated, was sharpiy acid to litmus, and contained hydrobromic acid. After two recrystallisations from hot alcohol, the solid was deposited in small, white prisms, melting a t 96-97' (corr.) ; they were dried in a, vacuum over sul- phuric acid and analysed, with the following results. 0.2922 gave 0.3072 BaS04. S = 14.45. 0.225 ,, 0.1893 A@. Br = 35.79. CousequentJy, the thiourethane, which would require 10.5 of S and 52.4 of Br, had not been produced, but, as in the corresponding experiments with amines, the addition product, if formed a t all, is unstable, and decomposes under the conditions of experiment, with elimination of the elements of hydrogen bromide, and production of a closed-chain compound.Theory for C6H,,NSOBr. Experiment. S.. ...... 14-30 14-45 Br ...... Y5.67 35.79 The substance is moderately soluble in hot water, much less so in cold (the solutioii has a distinctly acid reaction to litmus), freely i n boiling alcohol, but only sparingly at the ordinary temperature ; it dis- solves also in hydrochloric acid, from which it again separates on the32 DIXON : THE CHEMISTRY addition of dilute caustic alkali. It is not affected by boiling with alkaline lead tartmt e, and gives no colour reaction with ferric chloride.Neutral, or ammoniacal, silver nitrate throws down a ~ello~7~isli-wliite precipitate, which is decomposed by strong nitric acid, in. the cold, with formation of silver bromide ; tliis silver componnd is remark- ably sensitire to actinic light, rapidly changing in ordinary (diffused) claylight, through mauve and violet, to deep purple. On boiling, it i s not desulphurised, but, on tlie contrary, whitens somewhat, thereby losing, to a great extent, its sensitiveness to liglit. A very ~ o u g h coniparstiv-e experiment 011 the latt el* property was made, by adcling silver nitrate t o separate solutions of ammonium chloIide and tlie substance, and exposing the rcsnltant precipitates (Nos. 1 and 2 respectively) to dull cinylight : In one minute, No.2 began t o colour, whilst Nc!. 1 was yet not visibly affected; after seven minutes, a faint mauve coloration was perceptible in No. 1, No. 2, meanwhile, had acquired a strong purple coloui-. Marked annlogy appcars to subsist between the action of dibi-omo- propylthiocarbimide on the nitrogen buses, 011 the one lmnd, and ethylic alcohol on the other. In both cases, one-half of the thio- carbimidic bromine is elit~~inated in the forrr1 of hydrogen bromide ; the failure of the dcohol clerivative to desnlphurise uiider the influencc of lead, and especially of silver salts, points equally to the inclusion of sulp’lrui* as an integral member of an organic r i n g ; and on the principle already mentioned, regarcling the comparatively easy withdrawal of the end bromine atom, it is fairly sai‘e t o conclude that with respect to ring-closing also, the alcohol process runs a like course as in the case of the nitrogen bases (including ammonia).L4ccordingly, the interaction may be, at least provisionally, repre- sented as follows. the former product being the ethylic salt of P-bromotrimethylenc- I/ ?z.tliiocmbamic acid or, mom shortly, p-ethoxy-y-bromopent,hi- a I, ol i lie. This T V ~ S obtained from tlie thiocarbimide and pure inethylic alcohol by heating in a sealed tube for something over an hour a t 1 1 0 - 1 1 5 O ; there was slight pressure on opening it, and tl lit’tle lzjdrogen sulphide escaped, together with a fuming acid gas (HBr). The clear liquid product was evaporated to an oil, tvhich, on rubbingwith a glass rod; solidified ; the solid was dissolred in hot, dilute spirit, and, on cool- ing, separated as n nearly white, crystalline mass, melting, withoutOF D1BROMOPROPYLTHIOCARBIMIDE. 33 decomposition, at 95-96'.i n g with those required for the methoxypenthiazoline. 0.2011 gave 0.180 AgBr. 0.2005 ,, 0.2266 BaS04. S = 15.53. The methoxy-derivative is easily soluble in hot water and alcohol, rather sparingly in the cold. It is neither desulphurised by boiling with alkaline lead tartrate nor by ammoniacal silver nitrate; the latter precipitates a yellowish silver compound, whitening somewhat on standing in the dark, and, like the corresponding ethoxy-deriva- tive, very sensitive to even dull, white light. Figures were obtained on analysis agree- Br = 38.09.C5H,NSOBr requires Br = 38.05 ; S = 15.26 per cent. Dibromopropylthiocarbimide and excess of normal propylic alcohol were heated together as in the preceding experiment; on cooling, t,he originally turbid mixture* had given place to a crystalline solid pZus a clear liquid. There was no pressure on opening the tube, but the contents smelt of hydrogen sulphide, evolved a little acid vapour, and gave a strong acid reaction, due to hydrobrombic acid. After three recrystallisations from spirit, the solid was obtained in white, pyramidal crystals, melting, without decomposition, at 96-97' (corr.) . 0.2023 gave 0.2019 BaS04. pPropoxy- y- bromopenthiazoline is moderately soluble in hot water, easily in hot spirit, rather spariugly in cold. Like its congeners, it is not desulphurised, either by boiling with alkaline lead solution, or by neutral or ammoniacal silver nitrate. The latter reagent throws down a yellowish, amorphous derivative, changing, on boiling, to white; insoluble in dilute nitric acid, but decomposed by warming wit,h the concentrated acid, with formation of silver- bromide : this silver compound also (unless boiled) is sensitive to light in a high degree, and changes rapidly to mauve even in very dull daylight.I n a rude comparative experiment, similar to that with the ethoxy- compound, silver chloride was barely perceptibly altered in 10 minutes, the other silver derivative being then purple; in 15 niinutes, when a faint bluish coloration was beginning to show with the former, the latter had assumed a deep purple colour.S = 13.70. C,H,,NSOBr requires S = 13.47 per cent. The thiocarbimide dissolves tolerably freely in cold methylic alcohol, much less so in even anhydroua ethylic alcohol ; in propyiic alcohol it is ratner sparingly soluble. VOL. LXIX. D34 DIXON : THE CHEMISTRY A D D E N D U ~ ~ .-Imidazolines. The relations of the azoline compounds with which this paper is concerned are indicated by the typical formuke- Thiazoline. Penthiazoline. Imidazoline. Amongst thiazoline derivatives of the above type (apart from sub- stitukion in the carbon chain), p-hydrogen is alone replaceable ; the imidazolines, on the other hand, present two points where such replacement can occur, namely, CH(p) and NH(n). By the intro- duction into the latter, in either of these positions, oE sulphuretted groups, forms can result, in which the sulphur is contained without the ring, and which are isomeric both with one another and with the thiazolines.Thus, for example, taking a methyl derivative as start- ing point, and aseuming the substitution by a Rulphur radicle to occur solely in the ,mu-position, one thio and two imidic forms are possible, pMethylamidothitlzo1ine. p-Thiomel,hylimidazoline. n-Methylthioimidazoline. with two further possibilities if the n-hydrogen is in like manner replaced, or five isomers in all. The thio-compounds described below are imidazolines of the last-named, or n-, class, and were prepared - - CH2*NH from the imidic base p-methyiimidazoline," 1 >C*CH,. CH,--N p. U e t h y limidazo ly lphen y 1 thiourea, CGHO* N C ( SH) ON < ~ ~ 2 ~ ~ ~ ~ > Phenylt(hiocarbirnide and p-methylimidazoline were separately dis- solved in nearly anhydrous alcohol, and the soIutions mixed ; inter- action commenced at once, with evolution of heat, and white crystal- line matter quickly began to Repapate, the yield amounting to about $5 per cent.of that theoretically obtainable. On treating the product with boiling spirit, nearly t,he whole dissolved, leaving a trifling quantity of white, apparently amorphous, residue ; the filtrate from the latter, when cool, deposited thick, lustrous, white prisms, which, after again recrystallising, melted at 17.3-174' (corr.) to a yellowish c1ea.r liquid. Analysis for sulphur afforded the following result. * The material employed was a sample of " Lysidine," kindly supplied to me by Messre. Jeyes ; it is the 50 per cent. aqueous solution of the above base.35 0 f.’ DlBROMOPROPTLTHIOCARBIMIDE. 0,2359 gave 0.2184 BaS04. Cl,H,2X,S reqnires S = 14.62 per cent. The compound is, accordingly, an addition-product of base and thiocarbimide ; its formula is given above, and it may be named either p-methylimidazolylphenylthiouren, 013 12-pheuyl thiouramidu-p-methyl- imidazoline. It is slowly, and somewhat sparingly, soluble in hot water or alcohol, nearly insoluble in the cold, very sparingly in benzene, easily in cold, concentrated hydrochloric acid. Warm alkali dissolves it to a moderate extent, and the solution, when boiled with alkaline lead tartrate, is readily desulphurised ; the alcoholic solution, when mixed with animonixcal silver nitrate, blackens instantly. Tertiary thioureas, so far as my experience goes, are either not desulphurised at all by alkaline lead tartrate, or else only with great S = 14-33. difficulty, and after prolonged boiling ; this md the to be exceptional cases. following seem p-lllethy li?nidazolyl-orthotolylthiozi,.ea, CH3.CsH,*N:C( SH)*N<CH,.G3H,>N. C(CH )- This cornpound was prepared from the base and orthotolylthio- carbimide, as described for the phenylic homologue; the yield of crude product amounted to 92 per cent. of the theoretical. By crystallising from spirit alone, the product was slightly brownish, but, after further treatment with spirit and animal charcoal, it was obtained in fine, white crystals, melting at 159-159.5’ (corr.). The formula was checked by a sulphur determination. 0.2018 gave 0.202 BaS04. S = 13-76. C,,H1,,N,S requires S = 13.74 per cent. The compound is moderately soluble in water, freely so in boiling alcohol ; it resembles generally the preceding compound in properties, the potash-solu tion, moreover, is desulphurised moderately readily by boiling with alkaline lead tartrate. Ethyl- and aliyl-thiocarbimides also combined with the base on warming ; the products, in both cases, were sticky oils, which did not show any sign of solidification after long standing. Chemical Department, Queeia’s College, Cork.

ISSN:0368-1645    

DOI:10.1039/CT8966900017

出版商:RSC    

年代:1896

数据来源: RSC

摘要:

36 IV.-Studies of the Teqyenes and Allied Compouiids. New Dei-ivatives $*om a-DibronzocawLphor. By MARTIK OR'SLOW FORSTER, Ph.D., First Salters Company's Re- search Fellow at the City and Guilds of London Institute Centt8al Technical College. fiLtl.oaucto.r.y. THE behaviour of a-dibromocamphor towards nitric acid was studied more than 10 years ago by Kachler and Spitzer, who allowed a mix- ture of equal parts of concentrated and fuming acid t o act on dibro- mocamphor during a protracted period (Monatsli., 1883, 4, 554) ; they recorded the formation of dinitrobromomethane, camphoronic acid, C9H1205, hydroxycamphoronic acid, C9HI2O6, aiid a small quail- tity of a crystalline substance melting at 87-88', which may have the composition C2,H,,BrN40,2. From p-dibromocamphor and fuming nitric acid the same investigators obtained a nitro-P-dibromocamphor melting at, 130" (Il.lonatsh., 1882, 3, 218 : 4, 566).In the hope that light would be thrown on the structural relation- ship existing between a-dibromocamphor and the P-modification, Dr. Armstrong suggested that an attempt shonld be made to obtain a nitro-derivative from the former, isomeric with nitro-p-dibromocam- phor. On subjecting a-dibromocamphor to the action of fuming nitric acid (density 1-52>, it was soon observed that a somewhat. re- markable change takes place ; the substance is rapidly dissolved by the acid, and a t first the temperature falls, but then gradually rises spontaneously t o about 70°, when dense, mddy f urnes are liberated in large volume. Prom the oily product, a crystalline substance is isolated without difficulty, in quantity amounting to about 10 per cent.of the material used ; it is free from nitrogen, and has the com- position C,,H,,Br,O2.* Tlie conditions which affect the production of this substance nffoiad no clue to its chemical nature. A careful study of the derivatives to which it gives rim, however, reveals its lactonic character, the single oxygen atom by which its empirical formula differs from that of di- bromocamphor appearing t o enter the ring between the carbonyl group and one of the neighbouring carbon atoms. There is every * In n preliminary notice of the innzkigation (Proc., 1895, 4), this substance was described as having the composition Cl0HI2Br2O2. Study of its derivatives having shown that it must be represented by the formula CloH1,Br202, t,he numbers re- quired by this expression were calculated, and were found to agree more closely with the analytical resuits already announced (Zoc.cit.) than does the percentage composition of SL substance having the formula C10Hl,Br20,.STUDIES OF THE TERPENES AND ALLIED COMPOUNDS. 37 reason to suppose that the bromine atoms occupy relatively the same position as in a-dibromocamphor, it being unlikely that the forma- tion of the new compound affords an instance of rebromination, as, although bromine is liberated in the conrse of the action, the pre- sence of silver nitrate does not interfere with the production of the snbstance ; moreover, addition of bromine to the nitric acid used, does not augment the yield.A noteworthy fact in connection with this change is the importance of using the strongest nitric acid pro- curable ; in carrying out the investigation it has been customai-y to distil 500 C.C. of commercial fuming nitric acid (density 1.52) from 200 C.C. of Concentrated sulphuric acid, the operation being inter- rupted when 400 C.C. has passed over. The dibromolactone obtained in the manner indicated gives rise to an interesting series of compounds, and beEore passing on to the experimental matter with which the present communication deals, it appears desirable to give a brief sketch of these substances, and the manner in which they are related to one another. It crystallises very readily from organic solvents, forming long, pris- matic needles melting at 152" ; cold, concentrated sulphuric acid has no action on it, and it may be crystallised from hot, fuming nitric acid.The substance is indifferent towards plienylhydrazine, ani- line, benzoic chloride, acetic anhydride, and hydroxylamine, but is attacked by alkalis with great readiness. Thus alcoholic potash elimi- nates bromine, giving rise t o a lactone of the formula Cl,EI4O3, which, under the influence of a boiling solution of barium hydroxide, yields the acid Cl0HI6O1, melting at 20.3'. As will be seen from its empiri- cal formula, the lactone C,,H,,O, cannot be regarded as the substance of which the dibrornolactone is a halo'id derivative, and this is also shown by the fact that, on brominating the lactone? only one atom of the halogen entfers the molecule, a derivative of the composition CloH13Br03 being formed.It seems probable that the production of the lactone involves the displacement of bromine by hydrosyl groups, and the subsequent elimination of the elements of water. Whilst alkalis eliminate both bromine atoms from the dibromolac- tone, only one is removed by reducing agents. Simultaneously, how- ever, the lactone ring is split, and an unsaturated monobromocar- boxjlic acid is produced. This substance, which has the formula Cl0HI5BrO2, melts at 159"; it, forms well-defined salts, and has marked acidic characteristics, dissolving in a cold, aqueous solution of sodium carbonate, liberating carbon dioxide, and although but spar- ingly soluble in boiling water, the solution is distinctly acid towards litmus.Its unsaturated character is revealed by the behaviour of a solution containing sodium carbonate towards potassium The properties of the initial compound are most characteristic.38 FORSTER: STUDIES OF THE TERPER'ES permanganate, which it immediately decolorises, and also by the readiness with which bromine dissolved in chloro'orm is decolorised when mixed with a solurion of the acid in the same medium. The product of the latter change consists entirely of a dibromolactone, which it is to be supposed is formed by the elimination of hydrogen bromide from a tribromocarboxylic acid, incapable of existing in the free state. Fittig has shown that a similar behaviour towards bromine i s characteristic of /3-/-unsaturated acids, which take up two atoms of the halogell, and a t once part with hydrogen bromide, yielding ft P-bromo-y-lactone.The behaviour of the monobromocarboxylic acid towards sulphuric acid affords further evidence in favour of the view t h a t it is a /+pun- saturated acid. It is characteristic of these substances that, when snbjected to the influence of sulphuric acid, they are converted into the isomeric lactones, the investigations of Fittig aiid his pupils having shown that this behaviour is generally manifest in the aliphatic series, but is not met with among aromatic compounds ( B e y . , 1894, 27, 6668). When this test is applied to the acid from camphor, it is found to be converted by sulphuric acid into an isomeride which crystnllises in uiagnificent, lustrous plates, melting at 93-44'. It has the properties of a lactone, and, on hydrolysis, yields an acid free from bromine.The bromolactone is a saturated compound, being indifferent towards bromine, and fuming nitric acid has no action on it, whereas the isomeric bromocarboxylic acid readily yields a nitro- compound. Although the halogeli in the bromocltrbosylic acid resists the action of such reducing agents as zinc and acetic acid, sodium and alcohol, or tin and hydrochloric acid, the bromine is completely eliminated when R solution of the sodium salt is submitted to prolonged treatment. with sodium amalgam at the temperature of boiling water. The product, which has the formula C,,H,,O,, melts a t 161", and exhibits the character of a &-unsaturated acid, It dissolves in a cold aqueous solution of sodium carbonate, liberating carbon dioxide, and the solution i n hot water is acid towards litmus ; potassium perman- ganate is immediately decolorised when added to st cold, alkaline solution of the acid.The solution in chloroform at once decolorises bromine dissolved in the same medium, and hydrogen bromide is liberated, a monobromo1acto:~e of the composition C,,,H15Br02 being formed, which melts a t 62', and is isomeric with the bromolactone obtained directly from the bromocarboxylic acid. When the carboxylic acid, C10H1602, is dissolved in concentrated aulphuric acid, it is transformed into an isomeric lactone which melts at 176-177" ; it resembles camphor in appearance, has the odour of that substance, and sublimes slowly a t 100'. Its properties are lac-AND ALLIED COMPOUNDS.39 tonic, and i t gives rise t>o an acid, Cl0HlSO3, which crystallises i n lustrous needles: and melts atl 179". ~~omencZat~ire.-The desivability of being in a position to refer without confusion to these substances has rendered necessary the adoption of some convenient system of nomenclature. On consider- ation of their empirical formulae, i t will be seen that the compounds in question arrange themselves into two classes, typified on the one hand by the carboxylic acid, C,,H1,O2, formed from the bromocarb- oxylic acid obtained from the original dibromolactone by means of alcoholic amnionia and zinc dust, and on the other from the isomeric lactone to which the acid gives rise under the influence of concentrated salphuric acid. It is proposed that refer- ence be made to the new acid as camphorenic acid, a name which indicates, by the syllable en, the unsaturated nature of the substance. The isomeric lactone will be called canzpholid, the termination olid indicating, according to systematic nomenclature, a compound of lactonic character. The product of the action of fuming nitric acid on a-dibromo-camphor is, therefore, dib~ouzocampholid, and the acid obtained on reducing this substance will be called brornocamphorenic acid.I t is proposed t o indicate the isomerism exhibited by the pro- duct of the action of sulphuric acid on bromocamphorenic acid, and the compound obtained from camphorenic acid and bromine, by referring to these substances as u-nzonobromocampholid and /~-WIO'IZG- bronzocampholid respectively.The generic relationship which runs through the new group o compounds will be, perhaps, more clearly illushated by the following scheme, intended to represent the steps by which it is possible t o pass from one compound to anot.her. a-Dibromocamphor, Cl0HI4Br20 ; in. p. 61" Dibromocampholid, C10H14Bi,202 ; m. p. 152'. I Brornocamihorenic acid, CloH1,ErO2 ; m. 11. 159'. r I Lactone, CloH1463 ; m. p- 174'. Bromolactone, Acid, C10H1604 ; Ci,Hl,BrO3; ni. p. 196-197". m. p. 203'. r I CloHl,BrO, ; m. p. 93-94'". Cxmphorenic mid, a-Monobro~ocnrnpholidl Oxidation acid, C10H1602; m. p. 161". CloH1606 ; m. F. 184'. I Campholid, ~-~onobro~~ocampholicl, Anhkdride, Cl0Hl6O2; inp. 176-1'77". Hydroxy-acid, C,,H,,BrO2; m. p. 62". C20H3003; m. p. 84-85".I c,lJlu,,o, ; 111. p. 179'. I n view of the relation bet,aeen dibromocampholici and campholid40 FORSTER: STUDIES OF THE TERPENES itself, it was to be expected that, when brominatec?, the latter would either give rise to the former, or become converted into one of the isomeric monobromo-derivatives. Campholid, however, is not attacked by bromine a t looo, and the two monobromo-derivatives are also indifferent towards the halogen ; moreover, camphorenic acid and the sodium salt are converted by bromine into /il-monobromocampholid, no trace of dibromocampholid being formed. When, however, the methylic salt of camphorenic acid is brominated, a mixture o€ mono- and dibromocampholid is formed. This is most likely owing to the effect produced on the neighbouring methenyl group by neutralising the carbosyl radicle.While this is free, bromination does not take place, and the halogen merely saturates the ethylenic linking, where- upon hydrogen bromide is eliminated, and this change leads to the formation of a monobromolactorie ; when, however, the carboxyl radicle is rendered inactive by the introduction of the methyl group, substitntion occurs in the neighbouring methenylic residue a t the same time, and the usual addition of bromine also takes place, the ethylenic linking becoming saturated, and this being followed by elimination of methylic ,bromide, the closing of the ring is effected, and a dibromolactone is formed. Xpec{fic Rotato9.y Power.-The lactones and unsaturated acids with which the present communication deals, are all optically active, and their examination has afforded striking evidence of the alteration in rotatory power athending ring formation.It has been already observed in the case of several acids belonging to the sugar group that the formation of the lactone ring involves a very marked alteration in the behaviour towards polarised light ; for instance, whilst gluconic acid has the specific rotatory power [a]= = -1.74" (Awnalen, 1892, 271, 78j, the lactone has [a]D = +68*2O (Ber., 1890, 23, 2626), and mannosaccharic acid, which is very feebly active, forms a double lactone which has [a]= = +201*8" (Bey., 1891, 24, 541). It is, therefore, interesting to observe that the changes involved in the pro- duction of such lactones as campholid and its bromo-derivatives are also attended with radical alterations in specific rotatory power.With regard to campholid, whilst camphorenic acid has [a]= = +179*4O in chloroform, the isomeric lactone has [a]* = +27.4" in the srtme medium. Bromocamphorenic acid has, in chloroform, the specific rotatory power [a]= = + 1441", whilst the isomeric a-bromocampholid has = + l O * Y o ; P-bromocampholid, the formation oi which involves elimination of hydrogen bromide from brominated cam- phorenic acid, has the specific rotatory power [=ID = 4-3.5' when dissolved in a certain proportion of chloroform, becoming inactive when the solution is more concentrated. Although systeniatic investigation of the influence exerted by theAND ALLIE,D COMPOUNDS. 41 solvent on the specific rotator3 power of these substances must be postponed for the present, experiment has shown that in the case of bromocamphorenic acid and p- bromocampholid, the use of benzene instead of chloroform is attended with a marked change in the rota- tion, and to a smaller extent dibromocampholid is affected in the same way.Thus the latter substance has [X]D = +64.5' in chloro- form, a solution of identical concentration in benzene giving [a]= = + 69.8. Bromocamphorenic acid has [all, = + 144.1' in chloroform, and + 161.3" in benzene, whilst p-bromocampholid has [a]= = + 3.5' in chloruform, and -21.2" in benzene. It would be possible to quote many instances o€ the influence on rotatory power which the nature of the medium exerts, for example, the recent observation of Herxfeld (Ber., 1895, 28, 440) , regarding the specific rotatory power of octacetylmaltose, which has been determined in chloroform and benzene, and is foulid to be [ a ] D = +614 and = +76*5O in the respective media. Whilst in this instance it is merely degree of rotation which is affected, rare observations of alteration in s i p have been recorded ; thus Freundler (Compf. Tend., 1890,117, 556), determining the specific rotatory power of propylic diacetyltartrate, found [a]= = +36*7" in carbon bisulphide, and -2%" in bromo- form.The camphor series, moreover, affords it still more striking instance of this phenomenon. a-Nitrocamphor has the specific rotatory power [a]j = - 7.5' in alcohol, and [ ~ ] j = -140' in chloro- form, whilst in tlie case of the /&modification, the value of [a]j is + 7.5" in alcohol, and -7.5' in benzene. One hundred grams of recrys tallised a-dibromocamphor are placed in a capacious flask (80 oz.), and covered with 200 C.C.of the strongest fuming nitric acid. The temperature of the liquid is at first sensibly reduced, and gradually rises spontaneously to about 70', a t which point a violent action takes place, rendered evident, by vigorous evolution of ruddy fumes, and the generation of much heat. When all action ceases, the liquid is allowed EO cool ; on pouring i t into a large volume of cold water, a heavy, brown oil separates, which is washed two o r three times with cold water, and subsequently agi- tated for about 10 minutes with boiling water. As a consequence of this treatment it, becomes very viscous, and acquires a pale yellow colour ; when freed from water it readily dissolves in twice its bulk of boiling spirit, and the liquid solidifies to a crystalline magma on cooling.After expressing the oily mot,her liquor, the residue is washed two or three times with cold alcohol, and then recrystallised42 FORSTER: STUDIES O F THE TERPENES from the minimum quantity of boiling spirit. Dibromocampholid is thus obtained in magnificent, lustrous needles, which frequently attain to more than an inch in length ; it melts at 152”. The following results were obtained on analysis. 0.1419 gave 0.1918 CO, and 0*0560 H20. C = 36.86 ; H = 4-31;. 0.2071 ,, 0.2806 CO, and O.OSl.4 H,O. C = 36.95 ; H = 4.36. 0.1044 ,, 0.1203 AgBr. Br = 48.54. 0.1076 ,, 0.1244 AgBr. Br = 49.13.0.1854 ,, 0.2133 AgBr. E r = 49.20. C,oH,,Br,O, requires c‘ = 36.81 ; H = 4.23 ; Br = 49.05 per cent. Although many attempts have been made to increase the yield of this substance by T-arying the conditions attending its formation, it has never been obtained in qnsntities exceeding in weight 11 per cent. of the material used. Thus i t is found that the use of smaller quantities of dibromocnmphor (5, 10 or 20 grams), or of a greater proportion of nitric acid, has no influence on the relative amount of the product, nor is the yield augmented on checking the vigour of the action by immersiiig the flask in cold water. If nitric acid, having tt lower density than 1.52 be taken, no spontaneous rise of temperature is observed. and almost the whole of the dibromocani- phor can be easily recovered froin the oil obtained on pouring the solution into cold water.As it appeared not unlikely that the formation of the compound involved a liberation of bromine and the consequent bromination of an intermediate product, finely powdered silver nitrate was dissolved in the strongesl furning nitric acid, which was then allowed to act on a-di bromocamphor. Silver bromide was obtained in quantity repre- senting 30 per cent. of the halogen available, but the yield of dibro- mocampholid was unaltered ; when, moreover, 20 C.C. of bromine was added to the quantity of nitric acid usually taken, act,ion proceeded in the ordinary manner, but 110 increase in yield was observed. Dibromocampholid is insoluble in water, and scarcely soluble in cold alcohol, but dissolves in the boiling solvent, and also in ether, chloroform, petroleum.acetone, and glacial acetic acid ; i t crystallises from ethylic acetate in magnificent, long, t~-ansp;~rent prisms, be- longing to the orthorhornbic, system. It snblimes at. a high temper- ature, and is somewhat volatile in an atmosphere of steam. The cornpound is indifferent towards bromine, and dissolves in concen- trated sulphnric and fuming nitric acids without undergoing chaiige, crystallising from the latter in long, transparent needles. It is in many respects a remarkably inert substance, and crystnllises un- altered from boiling aniline, phenylhydmzine, acetic anhydride, or benzoic chloride ; nhen it is heated, however, with an aqueous solu-AND ALLIED COMPOUNDS.43 tioii of sodium carbonate and alcohol, bromine is removed ; and the halogeii is a,lso eliminated when the substmame is heated for sc,iiie time with a mixture of equal parts of nitric acid (density 1.42) anti miter. Dibromocampholid undergoes no change when the soluticjn in glacial acetic acid is boiled for several hours with hydroxylamine hydro- chloride. The specific rotlatory power of a solution containing 1.0269 grams in 25 C.C. of chloroform was determined in a 2-decimetre tube at 11' ; the mean oE six concordant readings gave an = +5" 18', whence [a]D = +64.5". It has been already stated that the influence which the nature of the solvent exerts on the rotatory power of dibromo- campholid is more feeble than in the case of 13-bromocampholid and bromocamphorenic acid ; a solution in benzene of the above concen- tration gave aD = + 5" 40' at 15", whence [a]D = + 69.5".Hydrolysis of Dibyowocarnpholid. It has been already mentioned that elimination of halogen from dibromocampholid is readily effected by alkalis. The result of treat- ment with alkaline hydrolytic agents is the production of an &d having the formula CIOHI6O4, the lactone CloH,,O3 being obtained as an intermediate produck, in quantity varying according to the experi- mental conditions. Alcoholic potash is the agent most favourable to the formation of the lactone, whilst aqueous solutions of barium and sodium hydroxide give rise almost exclusively to the acid ; the actioii of these alkalis on dibromocampholid will be therefore described in the order named.Action of Alcoholic Potash o n DitroiIrocan~~holid.-Twenty grams of the finely powdered substance are covered with about 50 C.C. of boil- ing alcohol, and heateJ for three hours in a reflux apparatus with 23 C.C. of a n ,aqueous, 50 per cent. solution of caustic potash, which is added to the alcoholic liquid in small quantities at a time. The substance gradually dissolves, and the alkalinity produced by each fresh addition of potash is allowed to disappear before any more is added. The clear, red liquid, which is faiiitly alkaline, is allowed to cool, filtered from the potassium bromide which crystallises out along with unaltered substance (about 0.5 gram), reduced to small bulk by evaporat.iun, and set aside for 48 hours. 'l'he crystalline substaiice which separates during this time is freed from oil, washed two or three times with cold petroleum, and recrystallised from hot alcohol; it is thus obtained in lustrous plates, and melts at 1'74".From the analytical results, it will bc seen that the compound has the formula CloH14C),.44 FORSTER: STUDIES OF THE TER.PENES 0.1703 gave 0.4097 GO, and 0.1183 H20. C = 65.60; H = 7.71. 0.1227 ,, 0.2946 C02 and 0.0839 H,O. C = 65.48; H = 7.60. C,,H,,O, requires C = 65.93 ; K = 7.68 per cent. A solution of 1.1826 grams in 25 C.C. of chloroform was examined at 15" in a 2-decimetre tube; the rotation zD = -11" 6', whence The lactone is somewhat soluble in cold water, from which i t crys- tallises in thick, transparent prisms; it fuses to an oil in boiling water, which dissolves it readily, forming a neut'ral solution.Al- though insoluble in colci alkalis, i t dissolves readily when the solu- tion is boiled, and no precipitate is formed on acidifying the cold liquid ; it crystallises unchanged from boiling, aqueous ammonia. Phenylhydrazine has no action on it, and it is indifferent towards boiling acetic anhydride. The bromo-derivative, C10H13Br03, is obtained by the action of bro- mine on the lactone. When the dry substance is covered with the halogen, no change takes place a t first, but after remaining in contact for about a minute, action occurs quite suddenly, hydrogen bromide being liberated. The solid product is treated with sulphurous acid, washed several times with cold water, and finally crystallised from a considerable quantity of boiling alcohol, which deposits it, on cooling: in slender, lustrous needles melting a t 196-197".The following results were obtained on analysis. [BID = -117.3". 0.1406 gave 0.2375 CO, and 0.0657 H,O. C = 46.06; H = 5.18. 0.1460 ,, 0.1062 AgBr. Br = 30.91. ClOH,,BrO3 requires C = 45.98 ; H = 4.98; Br = 30.65 per cent. The bromolactone does not dissolve in water; it is insoluble in cold alkalis, but dissolves when the solution is boiled, and no precipitate is formed on acidifying the cold liquid. The halogen is eliminated on treatment with hot, alcoholic ammonia and zinc dust. Hydyolysis of the Lactone.-2.5 grams of the lactone were heated in a reflux apparatus for an hour with 40 C.C. of aqueous barium hydroxide containing 3 grams of the crystallised hydrate.A current of carbonic anhydride was passed through the filtered liquid, and, after being boiled for a few minutes, the solution was freed from barium carbonate by filtration, and evaporated on the water bath until crystals began to separate ; the substance thus obtained is the barium salt of the aeid CloH~60~, which is more conveniently obtained in the manner about to be described. Action of Bayium Hydroxide o n Dibror,iocam~holid.--The finely powdered substance is treated with successive quantities of a boil- ing, concentrated solution of barium hydroxide, in a flask provided with a reflux condenser; as long as any of the substance remainsAND ALLIED COMPOUNDS. 45 undissolved, the alkalinity produced by a fresh portion of the hydrate is destroyed on boiling the liquid for a few miuutes.When a clear solution is obtained, it is allowed t o cool, filtered from a small quantity of unaltered dibromocampholid, reduced to a small bnlk by evapo- ration in an open basin, cooled, and, after acidificalion with concen- trated hydrochloric acid, repeatedly extracted with ether. On evapo- rating the ether, after agitating the solution with fused calcium chloride, a pale yellow substance is obtained, which crystallises f roni a mixture of ether and petroleum in minute, transparent rhombo- hedra, and melts, evolving gas, at 203'. The following results were obtained on analysis. 0.1716 gave 0,3742 GO2, and 0.1312 H,O. C = 59-47 ; H = 8.49. CloH160, requires C = 60.00 ; H = 8.00 per cent. The acid is very readily soluble in cold water, forming a strocgly acid solution, which dissolves potassium carbonate with evolution of carbon dioxide ; the alkaline liquid immediately decolorises a cold solution of potassium permanganate.It is extremely soluble in alcohol, chloroform, ethylic acetate, and organic solvents generally, excepting petroleum, in which it is insoluble. A solution in chloro- form does not decolorise bromiue, but on boiling the liquid a violent disengagement of hydrogen bromide occurs, and a colourless dibTomo- derivative is formed, which cryshllises from alcohol in feathery aggregates, and melts at 159-160'; this substance is insoluble in cold alkalis. The ba~iurn salt is obtained by dissolving barium carbonate in a hot, aqueous solution of the acid ; it is also formed on hydrolysing the lactone, CI0H1,O3, with aqueous barium hydroxide. The solution is evaporated until the salt separates in white needles ; the crystals are collected, washed with alcohol, and dried at 100'.0.1501 gave 0.0641 BaSOp. Ba = 25.11. 0.1512 ,, 0.0642 BaSO,. Ba = 24-97. (C1,H,,O4),Ba requires Ba = 25-60 per cent. The barium salt is very soluble in cold water, but is insoluble in alcohol, acetone, and ethylic acetate; the aqueous solution has an intensely bitter taste. Action of Xodiwm Hydroxide on Dibi*omocanipholid.-The substance dissolves slowly in a boiling aqueous solution of sodium hydroxide, and, on evaporating the filtered liquid, rendering acid with concen- trated hydrochloric acid, and extracting several times with ether, the foregoing acid, CI0Hl6O4, is obtained on evaporating the solvent.If, however, the action of sodium hydroxide be allowed to proceed for a few minutes only, and the filtered liquid be extracted with ether46 FORSTER: STUDIES OF THE TERPENES previous to acidification, the lactoae, C,,,H,,O, (ni. p. 174O), is ob- tained. An attempt was made to hyd:.olyss dibromocampholid by means of dilute sulphuric acid. The powdered substance was treated with boiling sulphuric acid (2 parts of concentrated acid in 10 parts of water) for six hours in a flask provided with a reflux condenser, but the greater part of the substance remained undissolved, and when recrystallised from alcohol melted at 152'. Byomocanzphorenic acid, C,oH15BrOz. Fifty grams of dibromocampholid are covered with about 100 C.C.of boiling alcohol in a capacious flask, and to the liquid are added suc- cessively smali quantities of zinc dust, and strong, aqueous ammonia, the temperature being maintained nieariwhile on the water bath, until a portion of the clear, ammoniacal solution no longer becomes turbid when diluted with water. The liquid is then decanted from undissolved zinc, largely diluted with water, and finally acidified with dilute sulphuric acid, when a white, flocculent precipitate immediately separates ; this is collected, washed several times with cold water, and dissolved in a small quantity of hot spirit, from which i t crystallises in thin, lustrous plat,es. It frequently happens that on diluting the ammoniacal liquid, a yellowish-white, granular precipitate is thrown down ; this consists of the zinc salt, which is invariably produced when the solution remains in contact with hot ammonia and zinc dust for a period longer than that necessary for reduction.In this case, the product is washed with cold water, and dissolved in dilute caustic soda, the solution being then precipitated with sulphnric acid. The bromocarboxylic acid is readily soluble in cold alcohol, from which i t crystallises in transparent, six-sided plates, melting at 159' ; it dissolves readily in organic solvents, separating in well-formed crystals from glacial acetic acid and petroleum. It is insoluble in cold water, but dissolves sparingly on boiling, forming an acid solu- tion ; it is volatile in an atmosphere of steam, and sublimes at a high temperature.Analysis gave the following results. 0.1685 gave 0.3016 COz, and 0.0922 H,O. 0-1152 ), 0.0877 AgBr. Br = 32.35. 0-1175 ,, 0.0897 AgBr. Br = 32-44. Cl0HI5BrO2 requires C = 48.58 ; H = 6.07 ; Br = 32.38 per cent. A solution of 1.0060 gram in 25 C.C. of chloroform at 11' gave a rotation CXD = +11' 36', this being the average of seven concordant readings ; the specific rotatory power is, therefore, [ C C ] ~ = +144*l0. Dilution of the liquid appears to be without influence on the specific C = 48.81 ; H = 6.08.AND ALLIED COMPOUNDS. 47 rotatory power, at3 a solution containing 0.7247 gram in 25 C.C. of chloroform at 14' gnve a rotation zD = +So 22'; this coryesponds with a specific rotatory power [XI,-, = + 1 4 $ * 3 O , :L result sufficiently close t o the one already given to show the constancy of this property between the limits iiidic:+ted.The influence exerted by the nature of the medium is revealed when benzene is used as a solrent ; a solution containing 0.7850 gram of bromocamphorenic acid i n 25 C.C. of ben- zene at 15' gave a rotation The acid dissolves readily in cold alkalis, and it is also soluble in a cold, aqueons solutiou of sodium carbonate, carbon dioxide being %beratfed. No coloration is developed when ferric chloride is added to the dilute alcoholic solution, and it is indifferent towards Fehling's solution ; the alkaline solution immsdiately clecolorises potassium permanganate. The substance may be heated for an hour with boiling aniline without andei*goiii,o change, and a boiling alcoholic solution of sodium ethoxide has no action on i t ; when boiled during thyee hours w i t h an aqueous solution of camtic soda, it is precipitated unchanged on adding acid, and silver nitrate produces no turbidity in the filtrate.A solii tion in chloroform immediately decoloriscs bromine in the same medinm, and on evaporating the solvent dibrorno- cainpholid is obtained; the latter is also formed when bromine is added to the dry solid, much heat being generated, and hydrogen bromide evolved. Bromocamphorenic acid undergoes no change when allowed to remain for many days in contact with glacial acetic acid saturated with hydrogen bromide. The acid is indifferent towards hydroxylamine, benzoic chloride, and acetic anhydride, and undergoes no change when heated in a sealed tube with ammonia (sp.gr. 0880) for five hours at 170". Monobrornocamphoreuic acid may be also prepared by reducing dibromocampliolid with zinc dust and glacial acetic acid. The fol- lowing salts have been obtained. The barium salt is prepared by dissolving the acid in the niinimum quantity of an aqueous solution of barium hydroxide, and evaporating the liquid till crystals form. It separates fTom the concentrated solution in lustrous plafes, and in nodular aggregates wheu slowly deposited. From a specimen dried a t looo, the following analytical results were obtained. = +loo 8', whence [%ID = +161.3'. 0.2535 gave 0.0890 BaSO,. Ba = 20.64. 0.1963 ,, 0.0706 BaS04. Ba = 20.64. On analysing the same preparation dried at 130", 0.2003 gave 0.0733 BaSO,. Ba = 21-52.0.2148 ,, 0.0796 BaSOp. Ba, = 21.79. (C10H11Br05)2Ba + 2H20 requires Ba = 20.60 per cent. (CloH1,Br0J2Ba requires Ba = 21.78 per cent.48 Y'ORSTER: STUDIES OF THE TERPEXXS The silver salt is obtained by adding a slight excess of silver nitrate to an aqueous solution of the crystallised barium salt. The coloiirless precipitate is washed successirely with water, alcohol, and ether, and dried at 50'. I t is sparingly soluble in water, and dis- solves with difficulty in boiling alcohol, from which i t crystallises in lustrous needles. The dry salt darkens very slowly on exposure to light, but quickly blackens when treated with boiling water ; it does not explode when heated suddenly. Analysis gave the following results. 0.2294 (precipitated) gave 0.1211 AgBr.Ag = 30.30. 0.0652 (crystallised) $, 0.0346 AgBr. Ag = 30.46. CloHl,,RrOZAg requires Ag = 30.50 per cent. The z i 9 ~ salt is obtained as a yellowish, granular precipitate when an alcoholic solution of the acid is boiled for some time with ammonia and zinc dust ; it is also produced on adding an aqueous solution of zinc chloride to a neut'ral solution of the ammonium salt. The zinc salt is scarcely soluble in water, and but sparingly soluble in cold alcohol ; it is more readily soluble in hot alcohol, and crystallises from acetone in tufts of minute, transparent needles. On adding water to the hot, alcoholic solution, and allowing the liquid to cool, the salt is obtained in stumpy prisms. It dissolves in alkalis, the solutions yielding the acid when acidified.When heated at 130-14OG, the salt yields a colourless, crystalline sublimate oE the acid. This behaviour is explained by its composition, which analysis shows to be represented by the formula ( CloH14BrOZ)2Zn + C10H15Br0Z. Zn = 8.35. (CloH,4Br02)2Zn + C,,H,,BrO, requires Zn = 8-08 per cent, (CloHi4Br02)2Zn requires Zn = 11.67 per cent. The ammonium salt exists only in dilute, aqueons solution ; if this is evaporated, or saturated with carbon dioxide, the salt is decomposed, and the acid separates. The coppe?* salt is obtained by adding copper sulphate dissolved in water to the neutral, aqueous solution of the ammonium salt, a bluish- green, flocculent precipitate being formed ; when this is boiled with alcohol, a green solution is produced, and on adding a small quantity of water to the hot liquid and allowing it to cool, minute green needles are deposited.The methyZic salt is not formed when a solution of the acid in methylic alcohol is saturated at common temperatures with hydrogen chloride. It is prepared by dissolving 3 grams of the acid in a boil- ing solution of sodium methoxide in methylic alcohol containinp 0.3 gram of sodium, and adding small qnantities of methylic iodide uutil a few drops of the liquid, when diluted with water, no longer yield a 0.2626 gave 0.0274 ZnO.AND ALLIED COMPOUNDS. 49 solid precipitate on acidification. The excess of methylic iodide having been removed, the liquid is diluted with water, and the colourless oil which is thrown down is washed two or three times with cold water, and extracted with ether ; after being dried with calcium chlo- ride, the solvent is evaporated, and the residual oil distilled.I t boils at 255" under a pressure of 767.5 mm. The salt was andysed with the following result. C = 51.4 ; H = 6.7. 0.1792 gave 0.3379 COz and 0.1078 H,O. C1,,Hl4BrO2*CH3 requires C = 50.5 ; H = 6.5 per cent. The methylic salt is a colourless, somewhat viscous oil, heavier than water, having a fragrant odour suggestive of camphor; i t is volatile in an atmosphere of steam, the vapour being pungent and exhilarating. The salt is hydrolysed when heated with boi!ing alco- holic pot,ash f o r six hours; it burns GU platinum foil with a luminow, smoky flame, leaving no residue. The solution in chloro- form immediately decolorises bromine, and, on evaporating the liquid, dibromocamphoIid is left.Oxidation of Bromocamphorenic acid. It has been already stated that the acid dissolved in an aqueous solution of sodium carbonate immediately decolorises potassium per- rnangnnate ; an attempt was therefore made to obtain an oxidation product by means of this agent. Twenty grams of finely powdered bromocamphorenic acid was suspended in 200 C.C. of boiling water, sodium carbonake being added iiutil 3 clear solution was obtained; tbe liquid was t'hen cooled to about 0" agd mixed with an ice-cold, 2 per cent. solution of potassium pernianganate, which was added in portions of 100 C.C. Crushed icc was also added to the liquid in order to maintain the temperature at O", and when 1,500 C.C. of the permanganate solution (corresponding t o more than twice the molecular proportion) had been added, the liquid was allowed to remain f o r an hour surrounded with melting ice.After the removal of manganese dioxide, the clear liquid was concen- trated to 200 c.c., acidi6ed with concentrated hydrochloric acid, and t h e yellow solution extracted several times with ether. The pink syrup left on evaporating the united extracts rapidly solidified on being rubbed with a glass rod; the product was washed with hot ethylic rlcetate, and the colourless, insoluble portion dissolved in ether, which, when mixed with the same bulk of ethylic acetate, deposited the substance in groups of brilliant transparent prisms. The compound mells and evolves gas a t 184O, and, after having been allowed to cool, melts a t 84-85'; a specimen OF the fused substance, however, after recrystallisation from dilute alcohol, melted at 184O.ra. LXIX. E50 FORSTER: STUDIES OF THE TERPENES 0.1594 gave 0.3018 CO, and 0.0988 H,O. C = 51.63 ; H = 6.85. 0.1559 ,, 02967 CO, and 0.0944 H,O. C = 51.91 ; H = 6~73. CIoH,606 requires c = lil-72; H = 6.90 per cent. The oxidation product has the properties of a dibasic acid; i t is strongly acid towards litmus, dissolves readily i n alkalis, and with effervescence in alkali carbonates, and the aqueous solution, It dis- solves readily in cold alcohol and ether, being but sparingly soluble in cold ethylic acetate ; the solution i n boiling water deposits rosettes of minute, transparent prisms as the liquid cools. The silver salt was obtained as a pale yellow precipitate on adding silver nitrate in slight excess to a neutral solution of the ammonium Falt ; after being collected and washed successively with water, alcohol, and ether, the salt was dried in the desiccator.It darkens when exposed to light, or when heated for a few minutes in the water oven ; there is no explosion when the salt is suddenly heated. Probably owing to the unstable character of the salt, which gradually darkens even in a desiccator protected from light, analysis of tlie substance gave somewhat unsatisfactory results, which seem to indicate, however, that the acid contains two carboxylic groups. 0.1402 gave 0.0726 Ag. Ag = 51.78. 0.1926 ,, 0.0998 Ag. Ag = 51.87. CloH1406Agz requires Ag = 48.65 per cent. CioHi,QsAg, 3, A s = 58.58 9 , a-Monotrornocanzpholid, Cl:,,H1,BrO2.In the introduction, it was mentioned that bromocamphorenic acid shows the behaviour which aliphatic &unsaturated acids exhibit, when brought iii contact with sulphuric acid, undergoing molecular rearrangement, and being converted into the isomeric lactone. Finely divided brornocamphorenic acid is added in sinall quantities at a time to five tiiiies its m-eight of concentrated sulphuric acid, which is continuously stirred during the operation. Heat is developed, the substance gradually becoming dissolved, and when a clear solution is obtained, the pale brown liquid is poured into a large volume of cold water ; a white, crystalline precipitate a t once separates, and this is collected, and washed several times with cold water, If the sub- stmce is added too quickly to the acid, liberation of a small quantity of hydrogen bromide is observed, but this may be avoided by pre- venting 8 sudden rise in the temperature of the liquid.The lactone crjstallises from hot alcohol in magnificent, lustrous plates, separat- ing from concentrated solutions in long, slender needles ; it melts at 93-94O.AND ALLIED COMPOUNDS. 31 0.15'75 gave 0.2805 CO, and 0.0878 H,O. 0.1537 ,, 0.1183 AgBr. Br = 32.71. C,,H,5Rr02 requires C = 48.58; H = 6.07 ; Br = 32.38 per cent, The compound dissolves readily in organic solvents, and is soluble in boiling water, from which it separates as the liquid cools ; it may be cooveniently crystallised from a mixture of petroleum and alcohol, being obtained from this medium in thin, lustrous plates. It is volatile in an atmosphere of steam.Apart from its neutral character, the properties of a-monobromo- campholid differ very widely from those of bromocamphorenic acid. The lactone is iiisoluble in cold alkalis, and dissolves in bromine without undergoing change ; it is indifferent towards a boiling mix- ture of glacial acetic and fuming nitric acids, whilst this treatment converts bromocamphorenic acid into a nitro-compound. Potassium bromide separates immediately when a concentrated, aqueous solution of caustic potash is added to the boiling solution in alcohol, the original acid, in boiling alcoholic: solution, being indifferent towards metallic sociium. So easily is bromine eliminated from the lactone that, on digesting i t for a considerable period with boiling water, and filtering the cold liquid, a precipitate is at once formed on adding silver nitrate to the acidified solution.The conversion of bromocarnphorenic acid into the isomeric lac- tone is attended with a remarkable alteration in the specific rotatory power. A solution of 0.9549 gram of a-bromocampholid in 25 C.C. of chloroform was examined in a 2-decimetre tube a t 21"; a rotation =I) = +Oo 50' was observed as the mean of seven concordant read- ings, whence [a] D = + 10.9". Hydrolysis of a-~onobi.omocamp7olid,-~he lactonic character of the substance is revealed on treatment with an aqueous solution of barium hydroxide. After remaining in contact with the boiling agent in a reflux apparatus for thrce hours, the lactone becomes dissolved, and the alkalinity of the liquid is gradually destroyed ; on evapo- rating the solution which has been cooled and filtered, a barium salt crjst8allises in prismatic needIes.It was dried a t 130" for half an hour, an6 analysed with the following result. C = 48.57 ; H = 6.19. 0.1320 gave 0.0611 BaSO,. (CloH1,03),Ba requires Ba = 27-23 per cent. On acidifying a sclution of the barium salt, the acid is obtained as 5 colourless, viscous oil, which rapidly becomes hard and crystalline. It separates fram a mixture of petroleum and etbylic acetate in transparent prisms, and melts a t 195" ; it is very readily soluble in water, alcohol, ether, and acetic acid, but is iiisoluble in petroleum. The aqueous solution dissolves sodium carbonate with effervescence Ba = 27-21.E 252 FORSTER: STUDIES OF THE TERPESES the liquid having no reducing action on ice-cold potassium perman- gatlate. Campho renic acid, CI,-,Hl Bi-omocamphorenic acid is readily attacked by sodium amalgam, especially at slightly elevated temperatures. Pifty grams are suspended in 200 C.C. of boiling water and vigorously agitated during the addition of 4 per cent. sodium amal- gam in small quantities. It is necessary that the liquid should remain a t the temperature of boiling water, otherwise the reduction 3s incomplete, and a mixture of the new compound with unaltered substance is obtained ; as the separation of the latter is extremely tedious, the observance of this precaution is of some importance. For the quantity mentioned, about 500 grams of amalgam will be found sufficient, and when this amount has been added, i f a drop of &he liquid becomes solid when placed on a watch glass, it is decanted from the mercury and allowed to cool.The paste of fibrous needles t'htis obtained, consisting of the sodium salt of the reduction product, is collected, the alkaline liquid being removed by filtering through asbestos. uric acid, a white, flocciilent precipitate is formed, which is collected and washed thoroughly with cold water. I n order to completely remove the last traces of the original substance, the precipitated car- boxylic acid is again agitated with 50 grams of sodium amalgam, the separation and decomposition of the sodium salt being repeated ; as the latter only crystallises from strongly alkaline solutions, it is generally found necessary after this supplementary treatment with the amalgam to add sodium carbonate to the hot liquid until the sodium salt begins to separate.The acid, on being crystallised from hot alcohol, separates in long, slender needles ; it melts at 161". 0.1500 gave 0.3995 C02 and 0.1314 H20. C = 71.36; H = 9.73. Cl0H,,O2 requires C = 71.43 ; H = 9.52. 'The substance is very soluble in organic solvents, and dissolves to some extent in boiling water, being insoluble in the cold ; it crystallises fwm ether in transparent prisms which become opaque in the water oven. It is volatile in an atmosphere of steam, and sublimes when Leated, the vapour having a faint, camphor-like odour. A solution of 1.1840 gram in 25 c.c of cl~loroform was examined in a %decimeter tube at 18"; it exhibited a rotation of CXD = + 1 7 O , and the specific rotatory power is, therefore [ a ] ~ = f179.4". The substance dissolvca readily in cold, aqueous alkalis, and in a cold solution of sodium carbonate, carbon dioxide being evolved ; the so!ution in hot water is acid, and potassium permanganate is immedi- On dissolving the salt in water, and adding dilut2 sulphAND ALLIED COMPOU??DS.53 ately decolorised when added to the cold solution containing sodium carbonate. Boiling acetic arihydride has no action on the acid, which is also inditrerent towards benzoic chloride. The sodium salt, mhich separates from a strongly alkaline solution in tough, fibrous masses, is extremely soluble in water, and may be recrystallised from ethylic acetate, separating from this solvent in lustrous, silky needles ; a specimen obtained in this way was analysecl with the following result.0.2395 gave 0.0948 Na,S04. Na = 12-82. 0.2940 ,, 0.1161 Na,SO,. Na = 12.79. C10K1502N~ requires Na = 12.10 per cent. The Fornewhat unsatisfactory character of these numbers is most probably due to slight decomposition taking place a t the temperature of boiling ethylic acetate, as the crystallisecl salt does not redissolve completely in that solvent, and the solution i'n cold water is strongly alkaline. The zinc salt resembles that of bromocamphorenic acid; it is obtaiued on adding zinc chloride dissolved in water to a neutral solution of the amnionium salt. The methylic salt is not formed when a solution of the acid in methylic alcohol is saturated at common temperatures with hjdro- gen chloride, but it can be prepared by dissolving the sodium salt i n methylic alcohol and heating the solution with methylic iodide for several hours in a reflux apparatus ; on diluting the liquid with water, and extracting with ether, a colourless oil is obtained which boils at 215' under a pressure of 767.5 mm.It is viscous, and heavier than water, and burns on platinum foil with a luminous, smoky flame, leaving no residue ; it dissolves readily in alcohol, but is insoluble i n water. The salt is volatile in an atniosphere of steam, and the vapour has a very sweet, cnmphoy-like odofir ; it is hydro- lised when heated with alcoholic potash for several hours in a reflux apparatus.Its behaviour towards bromine is somewhat remarkable. Whilst by direct bromination of the original acid only one atom of bromine is introduced into the molecule, the methylic salt is violently acted on by the halogen, and is at once converted into dibromocampholid, certain quantity of p-monobromocampholid (see below) being pro- duced a t the same time. Anhydride of Caniphorenic Acid, C2,,H3003. Phosphorus pentachloride acts readily on camphorenic acid, but on pouring the liquid into cold water, or cold aqueous ammonia, and acidifying the solution, the unaltered substance is precipitated ; if,54 FORSTER: STUDIES OF THE TERPENTES however, dry ammoiiiurn carbonate be substituted for the free alkali, only a portion of the camphorenic acid is recovered unchanged, the remainder being converted into a non-nitrogenous compound having the formula of camphorenic anhydride.Five grams of the acid was intimately mixed with 7.5 grams of phosRhorus pent:ichloride, this quantity being in slight, escess of the amount calculated for one molecular proportion. A violent action took place, and the mixture became liquid ; in this condition it was poured on t o finely powdered ammoninm carbonate, and when the past? mass at first obtained had become solid, the product was thrown into cold water, i n which the greater pert dissolvcd. The insoluble por- tion was then 1-emoved, washed several times with cold water, and recrystallised from alcohol ; it separates from concentrated solutions in snow-white plates, and melts a t 84-85'.0.1334 gave 0.3692 CO, and 0.1148 H,O. C = 75-43 ; €3 -- 9.55. C20H3003 requires C = 75.47 ; H = 9-43 per cent. From the above quantity of camphorenic acid, two grams of the anhydride was obtained, rather more than this amount of the unaltered acid being recovered from the alkaline filtrate on acidification. The anhydride is indifferent towards boiling water, and may be mixed with alcoholic potash without undergoing hyclrolysip. It is very readily soluble in organic solvents, and is volatile in an atmo- sphere of steam. p-Mon ohm m ocampholid, C loEJT,,Br02. Whilst bromination of bromocamphoreriic acid gives rise to dibro- mocampholid, camphorenic acid is converted into a bromolactone iso- meric with the monobromocampl~olid already described as arising from the action of concentrated sulphuric acid on bromocainphorenic acid.Camphorenic acid is dissolved in cold chloroform, and bromine is added from a burette until tLe colour of the halogen is no longer destroyed. Before this stage is reached, heat is developed and hydrogen bromide evolved, and, on evaporating the solvent., a pale yellow oil is obtained, which rapidly solidifies to a crystalline cake ; this is drained on poroiis earthenware, crystallised from chloroform, and finally from ether. The substauce melts at 62". The following results were obtained on aualysis. 0.1453 gave 0.2591 CO, and 0.0800 H,O. 0.1620 ,, 0.1241 AgBr. R r = 32.55. /3-Monohromocampholid is also formed when bromine is added to The action is violent, C = 48.65; H = 6-11. C,,ETl,BrOz requires C = 48.58; H = 6.07; Br = 32.38 per cent.the dry sodium salt of camphorenic acid.AXD ALLIED COMPOUNDS. 55 b h g accompanied by a hissing noise, and the development of milch heat ; liberation of hydrogen bromide is, however, not observed. The new isomeride is extremely soluble in organic solveuts, and crystallises from ether in hard, transparent prisms ; it separates from clilute acetic acid in thin, lustrous plates, and the concentrated soh- tion in alcohol deposits long, striated prisms. The substance is somewhat volatile at looo, the vapour having a pleasant odour resembling that of a-dibromocamphor ; it is volatile in an atmosphere of steam. Attention has been already drawn to the fact that dibromocam- pholid is converted into bromocamphorenic acid under the influence of alcoholic ammonia and zinc dust.An analogous change takes place when F-bromocampholid is reduced in this manner, campho- rer?ic acid being formed. The lactone is indifferent towards bromine, and is attacked very S ~ O W ~ J - by hydrolytic agents. The specific rotatory power of P-bromocampholid bas been the subject of comment in the introductory portion of this paper, it having bcen observed that the concentration of the solution and the nature of the solvent exert a marked influence on this property. 1.0179 gram dissolved in 25 C.C. of chloroform, at 15", was found to be inactive, whilst a solution containing 0.7006 gram, in 25 C.C. at the same temperature, gave aD = +Oo 12' as the mean of seven concordant readings, whence [a]= = +3.5".A ver.y different result, however, was obtained on using benzene as a solvent, although in the case of this medium concentration has but slight influence on the rotatory power. Thus, a solution contaiuing 0.8810 gram, in 25 C.C. of benzene at 16", gave aD = - 1" 30' as t-he mean of six concordant readings, corresponding to a specific rotatory power [a]D = - 2 1 * 2 O , whilst 1.3711 gram, dissolved in 25 C.C. at the same temperature, gave UD = - 2' 18, whence !a]= = -21.0". Campholid, C,oH IsO,. The transformation of bromocamphorenic acid into the isomeric a-bromocampbolid finds a parallel in the conversion of camphorenic acid into campholid under the influence of concentrated sulphuric acid. In describing the preparation of camphorenic acid, attention was drawn to the importance of effecting complete reduction of the bromocamphorenic acid, and as an instance of the tenacity with which bromine remains in the product, it may be mentioned that a specimen of campholid, obtained from camphorenic acid containing a small quantity of the halogen, was found to retain an appreciable amount of the impurity after passing successively through the opera- tions entailed in its preparation for analysis, namely, dissolution in sulphuric acid, crystallisation, and sublimation.It is possible, how-56 FORSTER: STUDIES OF THE TERPENES ever, to obtain a pure specimen of camphoiid by boiling the CI'U~LC' product during several minutes with alcoholic potash, and precipita- ting the lactone by water. Cnmphorenic acid, which has been reduced to powder, is added in small quantities to about five times its bulk of concentrated sulphuric acid ; as the substance dissolves, the temperature rises slight!y. When clear, thc pale yellow solution is poured into a latyp volume of cold water, and the white, flocculent, precipitate is collected, washed several times with cold water, and boiled during a few minutes with alcoholic potash, to which a considerable quantity of cold water is then added.After being washed carefully with cold water, the product is dried on porous earthenware, and crystallised from hot petroleum, separating as the solvent cools in minute, colourless crystals ; it melts at 176-177'. The following results were obtained on analysis. 0.1020 gave 0.2660 CO, and 0.9907 H,O. C,oK,,O, requires C = 71.43 ; H = 9.52 per cent.Campholid has the odour o€ camphor, and closely resembles thaC suhstance in appearance, moderate pressure converting it into a translucent mass, which, however, does not exhibit on the surface of water, the gyratory motion peculiar to camphor. It is an extremely volatile substance, and sublimes slowly below 100" ; when heated at the melting point, however, sublimation is extremely rapid, and i f the vapour is allowed to cool very slowly, campholid is deposited in beautiful, fern-like aggregates, composed of elongated octohedra, I h e substance is very volatile i n an atmosphere of steam, and the camphor-like odour of the hot vapour is extremely pomerlul. Campholid dissolves in most organic solvents with great readi- ness, and has not as yet beer, obtained in crystals having well defined geometrical structure ; i t is less readily soluble in cold petroleum, from which it separates in feathery aggregates when evaporation of the solvent is slow.The lactone is indifferent towards bromine, and is very slowly attacked by hydrolytic agents. A solution containing 1.0011 gram of campholid in 25 C.C. of chloroform was examined in a %decimeter tube at 17' ; the mean of seven concordant observations gave CLD = + 2 O 12', which corre- sponds t o the specific rotatory power [ a ] D = +27.4". C = 71.12 ; H = 9-88. r i Hydrolysis of Campholid. At one stage of the investigation, before the Jactonic character of campholid was recognised, it was anticipated t h a t the crtrbonyl group would possess ketonic properties, and an attempt was accordingly made to prepare an oxime; the product, however, consisted of a non-RXD ALLIED COBIPOITNDS.57 nitrogenous substance, which evidently arises fro= addition of the elements of water to the campholid molecule, the action being most 1ikeI-y due to the influence of alcoholic potash. 1.7 grain of the lactone was dissolved in alcohol cont'aining 2 grams of potassium hydroxide ; 1 gram of hydroxyl~~mine hjdro- chloride was then added, and the liquid heated for 15 hour on ths water bath, alcohol being added from time to time. It was then evaporated, tho residne being treated with watcr in order to sepa- rate the product from insoluble matter consisting of the unaltered lactone. On reducing the filtered liquid to small bulk, and ren- dering i t acid with concentrated hydrochloric acid, a pale, yellow oil separated, which rapidly became crystalline and hard when rubbed wit)h a glass rod; after being washed and dricci, the product mas crystallised from hot ethylic acetate, which dissolves it readily, allow- ing i t to separate in magnificent, lustrous needles as the liquid cools.The substance melts to a clear liquid a t 179", and erolves gas a t this temperature. 0 1612 gave 0.3798 CO, and 0.1376 H,O. C = 64-25 ; E = 9.48. 0.1743 ,, 0.4090 ,, ,, 0.1577 ,, C = 64.00; H = 10.03. The acid dissolves readily in organic solvents, but is only sparingly soluble in water ; it dissolves in an aqueous solution of sodium car- bonate, and the liquid thus obtained does not decolorise potassium permanganate immediately in the cold.The b a ~ i u n t salt was prepared by the protracted action of a hob aqueous solution of barium hydroxide oa campholid ; it separated in white scales on evaporating the solution, and was found on analysis t o contain 26-47 per cent. of barnin, tlie percentage required by tlie formula (C,oHliOd)2Ba being 2G.00. C,,H,,03 requires C = 64.51 ; H = 9-67 per cent. Theoretical, Although our knowledge of the structure of camphor in not SUE- ciently accurate to render the coiistitutional expression of the new derivatives a simple exercise, it may not be altogether unprofitable to discuss the relationship which they exhibit among themselves. It may be safely assumed that the complex *CHBr.CO. occurs i n bromocamphor, and there appears to be 110 evidence opposed to t b e view that tlhe group :CBr*CHBr*CO* is present in a-dibromocarrphor ; with this provision, the development of a scheme illustrating the mutual conuectioii betn-een these new compounds would present no great difficulty, were i t not for the fact that the tendency of recent, investigation is to show that the carbonyl group occurs in camphor as the member of a ring containing five carbon atoms.Thus58 E'ORSTER: STUDIES OF THE TERPENES F. Tiemann (Bey., 1895, 28, 2182) has advanced the conclusion that camphor must be represented constitutionally by the formula CH,.CH+~H-~O Assuming that a-dibromocamphor contains the group already indi- cated, this conception demands the representation of dibromocam- pholid by one of the formulae (CH,),C-C Br-CHBr CH3*CH.CH*O*CO I ( CH,) 2C- Q B r- H B c or I QH2 I I F H 2 9 C €I,* CH CH --C 0 Neither of these expressions, however, is in accordance with the properties of the substance.The bromocarboxylic acids derived from them would be +acids, having the constitution expressed by the formu1t-e (C HS),C--$):CH l.31- (CH,),C-F H-CHBr I YH2 and l v ! ' CH,*CH*CH.COOH CH,.CH*CH COOH respectively. A systematic study of the properties of +u:isaturated acids a s a class has been hitherto impossible, owing to the lack of general methods of preparation. I n the aliphatic series, however, allylacetic acid has been obtained, and is found to yield +dibromo- valeric acid on bromination (Annulen, 1881, 208, loo), and ybromo- valeric acid when combined with hydrogen bromide.The former substance has no tendency to pass spontaneously into a 8-lactone, whilst boiling water converts y-bromovaleric acid into the lactone of y-hydroxyvalerir: wid. The slight evidence arailable, therefore, seems opposed to the view that ?&unsaturated acids behave in the same way as those containing the ethylenic linking in the &-position, and i t is probable that if elimination of hydrogen bromide did follow immediately on the addition of bromine, as is the caaewith the latter class, the result would be the same as among these acids, so far as the structure of the lactone-ring is concerned, that i s to say, ylactones would be formed. Assuming this to be the case, brornocamphoyeuic acid should yield a dibromolactone, having the constitution expressed by one of the following f o r m u h .(C H,),C-Y ,;HBr, C H,-C H*CHP (C H,),Cl-y €3-7 HHr 'co a11 d 1 YE., 1 y;,"" CI'I,*CH*CHBrAND ALLIED COMPOUNDS. 59 But it has been already staked that dibromocampholid is the pro- duct of this change, and if the constitution of that substance is to be represerited by the latter scheme, the former being obviously inappro- priate, it must be assumed that under the influence of nitric acid, the opens, and then re-closes, forming the complex ring *Q H*CHBr.yO CH, -- CBr* , an assumption which seems scarce!y tenable. yH*CHBr-$lO 'C €3 By*CH - 0 There is, moreover, another obstacle regarding the constitution of dibromocampholid as represented by the second of the above expressions. Camphorenic acid would have the constitution (CH,) ,C-yH--CH, I I flH I 1 CH,*CH*CH COOH \vbilst the formula CH,.CH*CH co \/ 0 wonld represent the structure of campholid, and it8 will be at once noticed that these expressions have been already adopted by Tiemrtnn (Zoc.cit.) in explaining the behavionr of /3-campholenic acid and di- hydrocampbolenolactone, .to which cam phorenic acid and campholid bear no resemblance, although they are respectively isomeric with these substances. Whatever conclusion is arrived at regarding the cor,stitntion of camphor itself, the relationshi 9 between the new derivatives will meet with explaiiation if the view be taken that dibromocampholid containfi *(?Br'cHBr'(?o 0 . :C The changes which result in the produc- the group tion of bromocamphorenic acid from dibromocempholid most pro- bably involve hydrolysis of the lactone .ring, substitution of hydrogen €or bromine, and elimination of hhe elements of water, as indicated in t'he following manner. -___... -... .yBr*CHBr.yO + - *$I~fI-/--CHBr*COOH *G*CHBr*COOH. OH H :c--;--o *CiOH ._._.___...... i , - :c The last of these expressions represents the complex occurring in brou~ocamphorenic acid, and assuming that an acid of this nature would exhibit the behaviour of aliphatic py-unsaturated acids, the action of bromine and sulphuric acid mould give rise to compounds containing the groups60 STUDIES OF THE TERPENES ASD ALLIED COIIPOUNDS. *qBr* CHBr-yO *CH.CHBr*QO and I : C- 0 :C 0 ' peculiar t:, dibromocampholid and a-monobromocampholid respec- tively. Under the influence of the snme agents, camphorenic acid would yield compounds in which occur the groups *qBr*C H2* Q 0 : C-- 0 :C- -9 H-CH,.? 0 0 ' and which are most likely present i n P-bromocampholid and cumpholicl respectively. The s t e p by which reduction of the former gives rise to camphorenic acid, would then be pal-allel with those changes which result in the production of bromocamphorenic acid from dibromocam- p holid. It is anticipated that oxidation of the new derivatives will throw light on their constitution, and experiments are being now carried on i n this direction. I cannot conclude this paper without expressing my indebtedness to Professor Armstrong and 3r. KiFpizg, iiot only for the interest, they have exhibited in the progress of the work, but also for t h e valuable advice of which I hare frequently had the benefit. Note by Dr. Armstrong.-I desire to take this opportunity of point- ing out that the investigation of the derivatives of camphor con- taining halogens, is a t present being pursued in a variety of directions i n my laboratory. Although, as Dr. Forster sass, there is no evidence opposed to the view that the bromine atoms in a-dibro- mocamphor are attached to different carbon atoms, and the peculiar readiness with which one is eliminated, lends much support to this view, there are not a few facts which are difficult to reconcile with such a conclusion. Dr. Foi-ster's work-ilkeresting its are the results-has not thrown the light on this question I had anticipated. Xt is to be expected that the investigation of the nitrocamphoih derivatives, and of the derivatives containing two different halogens, as well as the comparison of a- with ,'3-dilsromocamphor, will afford evidence of the desired characte~. The important discovery of :L cis- and tyans-nitrobromocamphor made by Urs. Kipping and Lapworth (Proc., NO. 157, 209), is of special interest in this coil- nection. I may mention that Dr. Lapworth has proved that when a-dibromocamphoi- and bromochlorocamphor are sulphonated, the halogen is partially displaced, products different from those investi- gated by Kipping and Pope being formed. fi-IIibromocamphor has also given interesting results. CTzemical Departnz ent, City and Guilds of Londou Ceiitrnl Tzchnical College.

ISSN:0368-1645    

DOI:10.1039/CT8966900036

出版商:RSC    

年代:1896

数据来源: RSC

摘要:

61 V.--zu-B.romoca~pJ~o1.ic Acid. By F. STAXLEY KIPPING, Ph.D., D.Sc. A LrHouGR the bromocamphoric anhydride, which was first preparcd by Wredcn a long time ago (Aiznaleiz, 1872, 163, 330), has been in- vestigated by several chemists during recent years, the corresponding bromocamphoric acid has not hitherto been isolated. As is well known, the anhydride is slowly decomposed by boiling water, yielding, as principal product, camphanic acid, C,,,H,,Br03 + HZO = CroHI4O4 + HBr, the lactone of a hydroxycamphoric acid which, apparently, does not exist, except in the form of a salt. A similar change occurs when bromocamphoric anhydride is boiled with sodium carbonate solution, but, under these conditions, as Aschan has receutly pointed out (Bey., 1894, 27, 2112), a much larger quantity of lauronolic acid is formed than is the case when water alone is employed.The fact that bromocamphoric acid has never been found amongst &he various products obtained from the anhydride on treatment with water or alkalis, might be accounted for in one of two ways; it might be, as Ascban assumes (loc. c i t . ) , because bromocamphoric acid, 1 ike dimethylf umaric acid (pyrocinchonic acid), and diethylfumaric acid (xeronic acid), for example, is actually incapable of existing nnder ordinary conditions, owing to the readiness with which anhy- Qride formation takes place ; or else because the acid loses hydrogen bromide and passes into camphanic acid with extreme facility. In the course of an investigation of 9-bromocamphoric acid (Proc., 1S95, 33, 88, and 210), the results of which will form the subject of a future paper, this question of the possible existence of a bromocam- phoric acid, corresponding with Wreden’s anhydride, came into pro- minence.n--Bromocemphoric acid, CloH15Br04, a structural isomeride of the cnknawn bromo-acid, was found to be stable under ordinary conditions, as was also n--dibromocamphoric acid, Cl,H,4Brz01, a com- pound in which one of the bromine atoms doubtless occupies the same relative position in the molecule as the halogen atom in Wreden’s bromocamphoric anhydride. These observations seemed to indicate that suitable conditions alone were required for the successful preparation of the bromocam- phoric acid in question ; this conclusion was ultimately verified by experiment.On treating Wreden’s bromocamphoric anhydride with concen- trated nitric acid in thc manner described below, it is partially trans- formed into the corresponding acid of the composition CloH1,BrOa ;62 KIPPING : W-BROMBIOCA.MPHORIC ACID. this acid is a well-dehed, crystalline, moderately stable compoul~d, which closely resembles the z--bromo- and 7-dibromocamphoric acids in ordinary properties. As it is convenient to have some means of distinguishing by name the two structurally isomeric monobromocamphoric acids now known, the compound derived from Wreden's anhydride will subse- quently be referred to as w-bromocamnphoric acid ; a purely arbitrary designation of this kind (the initial letter of Wredcn's name), has, no doubt, its disadvantages, but is probably less misleading than a11~7 other.In a recent paper (Bey., 1594, 27, 2112), Aschan describes the results of some experiments on zu-bromocamphoric anhydride ; on treating I-isocamphoric chloride with bromine, he obtained as priri - cipal product 2.0-bromocamphoric anhydride, and in oue experiment, he also succeeded i n isolating a very small quantity of a brominated acid, which separated from water i n long needles, melting a t 1 9 6 O . Although unable to obtain sufficient for an analysis, he studied the action of sodium carbonate on this brominated acid, amd, from its behaviour, concluded that it was probably a bromisocamphoric acid, CloH,,BrOa. I n the last nuinber of the Berichte (Re?-., 1895, 28, Ref., 922), there is an abstract of another paper by the same authoy, and it is there stated that I-bromisocamphoric acid has been isolated from the products obtained on brominating d-camphoric acid and I-isocamphoric acid ; this coinpound is described as separating from benzene in crystals of the composition C,oH,,BrO1 + &C,Hs, and melting at 196'.Unfortunately, the original publication (&a. soc. scient. "fenn,., 21, No. 5, 1) is not yet accessible, so that it is impos- sible, from the data a t hand, to say with certainty whether Qschan's acid, which appears t,o be the same as that mentioned by him in tlie earlier paper (Zoc. cit.), is identical with, o r different from, the w-bromocamphoric acid described below. I n his interesting paper (Bey., 27, 2001) on the relation between the various camphoric acicls, Asckan himself has shown that the hvorotatory w-bromocamphoric anhydride is partially converted into I-isocamphoric acid on reductioii with zinc dust and acetic acid, from which it would be concluded that simple hydrolysis of the lmvoro t atory zc- bronio- anh yd ride s ho u 1 d also afford I-bromisocamphoric acid.The praperties of Aschan's 2-bromiso- camphoric acid, however, are certainly different from those of the compound obtained by the author ; although, apparently, the t n-0 substances have practically the same melting pointl, w-bromocsiii phoric acid is insoluble, or nearly so, in benzene, and cannot be recrystallised from water ; at ordinary temperatures it is practically insoluble in this liquid, and, even 011 boiling, i t passes iiito solntioii only very slowly, being a t the same time decomposed.KIPPING : 21’- BHOMOC XMPHORIO ACID.63 Pr eparnt io l.2 of w - Bromocamp h oric Anhydride. -The preparation of the material required for this investigation was very kindly under- taken by Mr. Pauisset, a student of the Chemical Department of the Central Technical College, the method adopted having been that described by Reyher (Inaug. Diss., Leipzig, l89l), which seemed more convenient than Aschan’s process when small quantities only are required. The bromine having been added gradually to the mixture of pure d-camphoric acid and aniorphous phosphorus, until the evolution of hydrogen bromide suddenly slackened, the heating on a water bath was continued for a short time, in order to volatilise the excess of halogen ; water was then added, in small quantities at a time, cooIing well, and later on a little alcohol, in order to dissolve the oil with which the crystals were mixed.The product was then separated by filtration, washed with a little alcohol, dried on porous eartheuware. arid purified by reciytallisation from chloroform ; 8.5 grams of camphoric acid gave 7 grams of crude crystalline product, from which 5.4 grams of pure w-bromocamphoric anhydride were obtained : the yield was therefore about 50 per cent. of the theoretical, or much the same result as that obtained by Reyher and Aschan. w- Byornocamphoric acid. The pure w-bromocamphoric anhydride (m. p. 214O), in quantities of 2-5 grams, was placed in a small, glass, evaporating basin, and rather more than covered with concentrated nitric acid (sp.gr. 1.42) ; the basin was then covered with a clock-glass and heated on the water bath. The anhydride quickly passed into solut.ion, especially on stirring, and a slight evolution of ruddy fumes was obserred, but there was no odour of bromine. As soon as all had dissolved, the clock-glass was removed and the heating continued during two or three minutes longer ; the solution was then allowed t o cool, diluted with water, and the colourless, crystalline product separated by filtration, washed with water, and placed ou porous earthenware. A s 60071 as it appeared to be dry, i t was treated with a relatively large quantity of cold chloroform; the greater part, consisting of large crystals of w-bromocamphoric anhydride, soon passed into solu- tion, but a small portion of a crystalline powder did not dissolve; this was separated by filtration and washed repeatedly with chloro- form, first on the filter and finally on unglazed earthenware.This product was fonnd to be an acid, and at first it seemed possible that i t might be the isocamphanic acid, C,,H1404, described by Reyheia (loc. cit.), this substance being also practically insoluble in chloro- form; as, hoEever, the two compounds diffei-ed considerably in melting point, this possibility was excluded.6k KIPPISG : ZU-UftOXOUAJlPHORIC ACID. Camphaiiic acid, the formation of which under the above conditions was not improbable, is so readily soluble in chloroform that its presence was impossible ; tlie compotmd obtained i n the manner just described was therefore some new derivative of w-bromocamphoric anhydride.As 5 grams of the anhydride had only a,fforded 0.2 t o 0.3 gram of the neiv acid, a few attempts were now made to improve the method of preparation, but not with any success. On heating the bromo- anhydride with concentrated nitric acid during a longer time than 3-4 minutes, i t undergoes oxidation to a greater extent, the yield of the desired product is no larger, and a greater proportion of the anhydride is wasted. The use of a larger quantity of nitric acid, with the object of preventing crystallisation until the solution had cooled t o a temperature considerably below looo, appeared also to give no better results. The original method was, therefore, again adopted, the anhydride, which was recovered in a practically pure condition on evaporating the chloroform extract of the crude product, being continually used for a following experiment ; working in this way, 4.7 grams of the anhydride, after three operations, gave rather more than 0.7 gram of the pure acid, and 3% grams of the anhydride were recovered ; it is consequently an easy matter to prepare the acid i n moderately large quantities.The crude crystalline acid, freed from anhydride by repeatedly washing with chloroform, was dissolved in dry ether, the filtered solution evaporated to a small bulk, and mixed with a large quantity of chloroform ; the crystals which were at once deposited from the hot solution were then separated by filtration, washed with chloro- form, and heated for a short time in a water oven.An analysis of this preparation gave results agreeing well with those required for a bromocamphoric acid. 0.1527 gave 0.2404 CO, and 0.0745 H,O. C,oH,,BrOa requires C = 43-01 ; H = 5.37 per cent, That the substance is a bromocarnphoric acid corresponding with Wreden's anhydride is amply proved by the experiments described 'below. To-Bromocamphoric acid crystallises from a hot mixhre of ether and chloroform in small, transparent prisms or plates, but, when crystallisation takes place slowly at ordinary temperatures, the acid is deposited in large, orthorhombic pyramids ; it melts at 195-196', at the same time effervescing violently and charring slightly. It is practically insoluble in chloroform and in benzene, but it dissolves freely in cold ether, acetone, and alcohol; in these respects, it rc- sembles the r-bromo- and r-dibromo-camphoric acids (Proc., 70c.cit.). C = 48-93 ; H = 5.43.KIPPING : W-BR~MOCAMPHORIC ACID. 65 When a concentrated solution of the acid in sodiutii carbonate is warmed for a few minutes and then acidified, an oily or crystalline precipitate is produced : this product is formed with elimination of hydrog.cn bromide, and should, therefore, be ordinary caniphanic Lcid. In order to prove this, some pure w-bromocarnphoric anhydride was boi!ed for a short time with sodium carbonate and dilute alcohol, and the camphanic acid thus prepared was compared directly with the compound obtained in a, similar way from the w-bromocamphoric acid. Both preparations crystallised from dilute alcohol in fern-like prisms, and in long needles, identical i n appearance ; these crystals in both cases melted in theiy water of crystallisation when suddenly heated at about 140' ; but after recrystallisation from chloroform, in which they were readily soluble, both specimens me1 ted, although not very sharply, st 198--200° (pure cxmphanic acid melts at 201").When finely divided w-bromocamphoric acid is shaken with a, fairly large relative quantity of cold water, it does not dissolve to any appreciable extent, but on boiling it slowly passes into solution ; this solution gives a precipitate immediately on the addition of a solution of silver nitrate, but it does not give a crystalline deposit on simply cooling, unless it8 has been previously concentrated to a very small bnlk; the needles which then separate are readily soluble in cold chloroform, and melt a t about lS8-20Oo after recrystallisation.w-Bromocamphoric acid is, therefore, decomposed by boiling water, giving camphanic acid and hydrogen bromide, CloHl,BrO, = C,oH1404 + B B r ; from cold alcohol and acetone, however, it is, apparently, deposited unchanged, as the crystals are insoluble in chlo:*oform ; it may also be inferred that the dry acid is stable a t tempeyatures below about M O O , since me1 thing point determinations, under different conditions as to the rate of heating, give concordant results. A final proof that the compound here described is a bromocamph- uric acid, corresponding with Wreden's anhydride, is afforded by its behaviour with acetjl chloride ; it dissolves slowly in this liquid in the cold, and seems to be deposited unchanged on evaporating the solution a t ordinary temperatures ; when, however, the solution is warmed for a sliort time, the acid is converted into its anhydride.This anhydride is readily soluble i n hot chloroform, but only spar- ingly in ether: and separates from a mixture of these solvents in colourless prisms melting a t 214O, and identical in other respects with the crystals of w-bromocamphoric a n h y d d e ; a mixtare of this pre- parat ion with some pure w-bromo-anhydride melted sharply at 2 1 4 O . The above account of the properties of zu-bromocamphoric acid explains the difficulty met with in its preparation ; on the one hand, VOL. 1,XIX. Y66 PATERSOK : EFFLOlIEECESCE OF the anhydride is not very easily hgdrolysed ; on the other, the bromo- acid is readily converted into camphanic acid. During this investigation it has often happened that, solutions of u:-bromocamphoric anhydride in chloroform have been rapidly eva- poi-ated on a water bath in order to recover the anhydride ; in some cases, b u t by no means frequently, the solvent may be removed almost entirely before crystallisat ion commences, arid a highly supersaturated solution results ; when, filially, crjstallisation occurs i t is attended with a fairly loud report, and the liquid contents of the cesscl are dmost instantaneously transformed into a dry, ra.ther bulky, mass of small crjstnls, free from any visible quantity of liquid chloroform, although still smellirg slightly of the solvent. Cheutical Research Laboratowj, City and Guilds (3 London CEntrul Technicai College.

ISSN:0368-1645    

DOI:10.1039/CT8966900061

出版商:RSC    

年代:1896

数据来源: RSC

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66 PATERSOK : EFFLOllEECESCE OF‘ V.I.-E$orescence of Double Ferrous Aluminium Sulphate o n Bricks exposed to Sulphur IIioxide. By DAVID PATEWON. IT is well known that in certain volcanic districts, such as in Sicily, the neighbourhood of Naples, Iceland, Auvergne, and elsewhere, natural alums are found in the shape of white effloresced salts pro- duced by the action of sulphurous rapours on aluminous minerals such as lava or trnchyte. An interesting example of the formation of a similar aluminous salt has been found on the bricks which form the inner v-ail of wool-bleaching chanibers, and which are thus ex- posed to the sulphur dioxide fumes employed i n the bleaching pro- cess. After the bleaching chambers have been in use for a year or so, there appears on various parts of the bricks, wherever there are most bases present, a white flocculent coyeying composed of clusters of glistening crFstalp, often beautifully and regularly crystallised.When such a cluster is broken up, it exhibits a silken or fibrous mass of white crystals resembling Kodule opened, showing crjstalline structure. asbestos in texture. This silken appearanw of these natural efflorescences has supge4ed the Fopular names “ hair salt” and “feather alum.” Their c r j stalline structur2 may be seen from the accomranying drawing tukcn from a specimen. TLcmore perfect of these crystals measured from 9 t o 10 mm. in length. In course of time, the bricks exfoliate ar,d become completely dis- integrated from the formation of crystals within them. When a brick is thus broken down i t is found t o be permeated with sulphur- ous and sulphuric acids, while little tufts of crystals are formed throughout its whole mass.Along with these white carysials, but in very small quantity, is sometimes found a dull, jellowish substance which, on subsequent analysis, was found to contain ferric sulphate. Various specimens of these salts were collected for analysis, and from the results obtained it was found that their composition closely agreed with some of the natural iron alums found in various parts of the world. The following, for instance, is an analysis given many years ago, by Forchhammer, of a natural iron alumiuium sulphizte in Iceland, and, when compared with the analyses of these salts formed on bricks exposed to sulphur dioxide, it will be seen they are very similarly constituted.Iceland Iroia A l ~ m ” (Forchhammer). FeO. Fe,O,. A1,0,. MgO. H2S0,. H,O. Total. 4-57 1.23 11.22 2.19 35-16 45-63 100.00 Samples 1, 2, and 3 were quite white, b u t 4 was OC a dull, yellowish colour owing to the presence of a larger percentage of ferric salt. The results of analysis were as follows :- Sample. Ferrous oxide. ..................... Ferric oxide.. .................... Alumina ......................... Magnesia ........................ Sulphuric acid.. .................. Sulphurous acid .................. Water .......................... Silica! lime, brick> insoluble matter., sulphur ...... i ~ 1. ~~ 5 -53 0 -49 11 *33 1 -06 42 -13 trace 89 *46 - -- I00 .oo 2. --- 5 -38 0 -98 9 -20 0 -65 40 *l4 trace 43 -65 - -- 100 -00 3. -- 5.65 0 -86 11 *45 0 ‘82 41 *09 trace 40 -13 - 4. -- 6-20 2 ‘05 7.96 1 24 39 -50 trace 38.49 4 *56 The above results show that these salts, from their varying com- position, cannot be regarded as definite chemical compounds, as no two analyses agree. If, however, their impurities be not taken into consideration, it will be found they closely resemble, on an average, the formula of a double ferrous aluminium sulphate, AI,(SO,), + FeSO, + 24Aq, as may he seen tlius.63 SCBUKCK AND MXRCHLEWSKI : Fe. Al. Sod. H,O. Irnpui.it,ios. Total. Found.. . . 5.61 5.76 , 4'3*:;7 4 b*:31 1.02 100 07 Theoretical 6-04 5.83 41-46 46.67 - 100.0 The chemical composition of the clay from which these bricks are made is as follows. Si02. A120,. Fe203. CaO. MgO. Alkalis.. H,O. Total. 64.50 14.80 2.05 5-43 6-10 3.FjO 2-65 100.0

ISSN:0368-1645    

DOI:10.1039/CT8966900066

出版商:RSC    

年代:1896

数据来源: RSC

摘要:

63 SCIIUNCK AND MARCHLEWSKI : V 11. -So me Derivatives of Anthrquinonc . By EDWARD SCHUNCK, Ph.D., F.R.S., and LEON MARCHLEWSKI, Ph.D. IN our previous communications, we gave a description of three differ- ent artificial methSlparpuroxantllins ; one of these was obtained by the condelisation of p.trat,oluic acid with metndihydroxybenzoic acid and was found by Hummcl and Perkin (Trans., 1894, 65, 854) to be iden- tical with a substarxe obtained by them from the $fang-lioudu roat. Another one was prepared by the action of benzoic acid on met:s- dihydroxj pnratoluic acid ; a comparison of this substance with rubiadin enabled us to point out the constitution of the latter. Finally we prepared a fourth niethylpu~puroxnntliin by the action of orthotoluic acid on metadih37droxybenzoic acid.The confititution i j i these four substances is represented in the following graphic formule obtained by the action of benzoic acid on I. 1 I I loH 9 niet~dii~yr~roxypalrstoluic acid (Trans., co OH / \ / \ / \ c H ~ \A$/ 1894, 65, p. 184). CO OH '""' I I I 10, ' 973, and 1894, 65, 183). V\/'/ rnhiadin from madder (Trans., 1893, 63, CO CH3 CO OH from paratoluic acid and metadihydroxy- 'I1* 1 I I IC)H ' benzdc acid (Trans., 1893, 63, 1137). A/V\ cH3 \A/\/ CO CH3C0 OH /"\'\ from orthotoluic acid and. metadihjdroxy- IV. 1 I I IoH ' benzoic acid. \Ac<\/SOME DERIVATIVES OF ANTH R h QUIXONE. 69 This substance has been prepared by us already a year ago. Up to the present the followirg two methylpurpuroxant~i~is were unknown. CO OH CO OH ~ H 3 A / \ / \ /\/\/\ *' ( I 1 IOH and I I 1 10, \/\/\/ c13:3 co /\Q/ It was to be expected that both these substances would be obtain- able by the action o€ metatoluic acid on metadihydroxybenzoic acid, since the former possessing an asymmetiical structure should be able to react wit,h the latter in two different ways, as shown by the follow- ing equatio:is.OH CO OH /\ CD3/\/\/\. CH/\COOH I 1 I 1 /OH = 2HsO -+ I A* L I +coorI\!oa v\c/o\/ Metrttoluic acid. Metadihydroxp- benzoic acid. OH CO OH B. ('"OH+ COOH, Me tat,oluic Me tadih y dro xy- acid. benzoic acid. The process of condensation was brought about in the following way : metadihydroxpbenzoic acid (1 part), and metatoluic acid (4 parts), were heated with solphuric acid (25 parts) for 10 hours at 110'. The dark brown solntion contaiuing the above mentioned methyl purpuroxan t hins, together with unaltered met ad ihg drox y benzo I c and metatoluic acids as well as anthrachrysone, the latter formed by the condensation of two molecules of the dihydroxy-acid, was poured into water and the whole extracted with ether; the ethereal extract was then evaporated and the residue treated with steam in order to expel unaltered metatoluic acid.Tlie remaining liquid mas again evaporated, and by extracting with boiling benzene, the methylpurpuroxanthins were dissolved ; the separation of the substances contained in this benzene solution is very difficult since the two methylpurpuroxanthins which are foi*med, like the methyipurpuroxanthins in general, have very similar pro- perties. Two substances differing from one another in their melting points may however be obtained in the following manner.The benzene is evaporated and the residue, which melts at ahont 225-235", is dissolved in boiling alcohol ; to this solution, an equal70 SCHUNCR AND JIARCHLEWSKI : volume oE benzene is added, and the mixture, if left, for some time, deposits orange coloured needles ; these are collected and subjccted to the same treatment several times, whilst the first filtrate must be evaporated and the residue treated again in a similar manner. Finally two substances with different melting points are obtained, of which the more easily soluble has the lower melting point; but we think that it would be useless to mention their respective melting points, as we were unable to completely separate the two.(I.) Analysis of the substance with the higher melting point. ([I.) That of the lowela melting point. I . 0.1021 gave 0.2642 CO, and 0.0379 H,O. C = 70.66 ; H = 4.12. 11. 0.0988 gave 0.2561 CO, and 0.0339 H,O. C = 70.60; H = 3.80. I n order to determine the constitution of these two substances, we stndied their products of oxidation. The substance of lower melting point, of which we had st some- what larger quantity, when mixed with dilute nitric acid (1 : 10) and heated on a water bath, gradually dissolved giving a bright yellow solution, which left a yellowish residue on evaporation. This was redissolqed in hot water and lead acetate added ; the white precipi- tate thus produced, being finally decomposed with dilute sulphuric acid, and the mixture extracted with ether.The ethereal solution after evaporation gave nearly white crystals, which on recrystalliua- tion melted a t 216". The acid was evidently a tricarboxylic derivative of benzene, and, judging by the melting point and its general properties, murt have been I : 2 : 4-trimellithic acid, C6H,(COOH),, and the constitution of the lower melting methylpurpuroxanthin is represented therefore by the formula A (p. 69). The body witli higher melting point, when treated in asirnilar way, gave a trace of a substance which melted at about 180°, and in all prohabiiity was hsmimellitl~ic acid, a circunistance which shows that the methylp urpnroxanthin of higher melting point has the constitu- tion represented by formula B. C15Hlo04 requires C = iO.86 ; H = 3.95 per cent.Methy~urpuroxaizthin, [OH : OH : CH, = 1 : 3 : 1'1. A mixtmre of 4 grams of dihydroxgbenzoic acid, 15 grams of ortho- toluic acid, and 200 grams of sulphuric acid was heatsd for 15 hours at 110-120°; the product was t,hen poured into water and extracted with ether; the residue left on evaporating the ethereal extract was suspended in water, and the excess of orthotoluic acid present driven off by means of a current of steam. This was followed by treatment with boiling benzene, arid the solution, on cooling, depo-SOME DERIVATIVES OF ANTI3RAQUINONE. 7 1 sited crystalline needles, which, after being recrystallised three times from hot benzene, melted a t 246O, and yielded the following results on analysis. 0.1254 gave 0.3249 CO, and 0.0484 H,O.It dissolves in alkalis, forming a red liquid. C = 7O 66 ; H = 4.29. Cl5.H,,,O, requires C = 70.86 ; H = 3-93 per cent. The solution in concen- trated sulphuric acid is brownish-red, and shows a narrow absorption band in the red. The substance is easily soluble in alcohol o r ether, and is obtained in orange-coloured, pointed prisms on evaporating the ethereal solution. Acetyl Uwicatire of ~~ethy123iiriourozanthin, [OAc: OAc:CH, = 1:3:1']. In order t o acetlglate the above methylpurpuroxanthin, i t was digested with acetic anhydride and a small fragment of stannous chloride ; the excess of acetic anhydride was then decomposed w i t h alcohol, and, after driving off the ethylic acetate, the residue was crystallised from alcohol. In this way a product was obtained crys- tnllising i n lustrous, silky needles, and melting at 195".It is not changed by cold alkalis, but is decomposed on heating with them. Ethers of ,41iza~in. We proposed some time ago the following formula €or the mon- ethers of alizarin, obtainable by heating alizarin with caustic potash arid an alkylic iodide, CO OH and we pointed out (Trans, 1894, 65, 186) that the natural methyl ether discovered by Humtnel and Perkin (Trans., 1893, 63, 1174) ill the Chay root contains, probably, t'he methyl groiip attached to the oxygen of the a-hydroxy-group. Thia view has been lately adopted by the above-mentioned chemists (Trans., 1895, 67, S19). We think that our suggestion finds experimental support in a work of Lagodzinski (Ber., 1895, 28, 1427) lately published.ThiH chemist obtained a monomethyl ether of alizarin by using hemipinic acid, OCHa72 SCHUNCR AND MARCHLEWSRI : which, considering the kind of reaction adopted, and the properties of the methoxy group adjoining one of the carboxylic groups, must have the same constitution as the ether formed direct by alkylisation of alizarin. The properties of both substances agree in every par- ticular, except as regards the melting point. Lagodzinski finds this to be 201°, whilst we determined it as 228", a new determination giving the same value. This differerice might be due to one of the substances being impurs ; we consider our preparation to be pure. Ethcrs of Aiathraquinoneoxime. I n a preliminary communication (Ber., 1894, 27, 2125), we showed that the oxime of anthraquinone can be easily etherified.It suffices to boil an alkaline solution of anthraquinonegxime with an alkylic iodide; after boiling for two o r three hours, the solution is poured into water, the deposit i s collected, and washed, firstly, with a weak solution of sodium hydroxide. and finally with water. We propose hers to describe these substances more accurately, but before doing so, some remarks coucerning the constitution of these compounds might be of use. The comtitution of the anthraquinoneoxime ethers may be in accord- ance with either of the two following formule, co co ' >o N*R The first formula would show that these ethers are so called oxygen ethers, whilst the second suggests that they are nitrogen ethers ; the method of preparation, however, would in all probability lend to the formation of oxygen ethers, as it is well known that the alkali salts of oximes are generally derivatives of t'rue isonitroso-compounds.Therefore the substitution of the metal by an alkyl group would cause the formation of an oxygen ether. This is supported by the following facts. If the berizyl ether of anthraquinoneoxime is boiled with strong hydriodic acid, benzylic iodide is formed, and is easily detected by its characteristic odour. Accordingly, if the methyl ether is heated with hydriodic acid i n an apparatus simiIar to Zeisel'P, metliylic iodide is given off. Were those compounds nitrogen ethers, benzylamine and methylamine respectively mould be formed.SO3fE DERIVATIYES OF ANTHRAQUINONE. 73 Jfeth yl Ether of ,4nt?wapuinoneoxime.This was obtained by the above-mentioned method. The product, after washing with a dilute watery solution of sodium hydroxide, was crystallised from dilute alcohol, the crystallisation being repeated three times. The methyl ether melts at 147", crystallises in yellowish needles and is easily soluble in organic solvents, especially ether ; the latter solution, when treated with hydrogen chloride, did not give any precipitate, and the residue left on evaporation melted at exactly the same temperature as the pure methyl ether. This fact again con- firms the above-mentioned formula, as it is known that nitrogen ethers of the oximes under these circumstances give hydrochlorides. 0.2091 gave 0.5836 CO, and 0.0899. The molecular weight determined i n the ethereal solution by meam k = 2110.C = 76.12; H = 4.77. Cl5H,,NO2 requires C = 75.94 ; H = 4.64 per cent. of the ebulioscopic method mas found to be normal. 0.2290 gave 46-14 Et. 4 = 9.045". Mol. wt. calculated = 237. 3101. wt. found = 234. Ethyl Ether 01. Anthraqninoneoxirne. The oxime was dissolved in absolute alcohol, a few drops of a cou- centrated solution of potassium hydroxide added, and the mixture boiled for three hours, after adding some ehhylic iodide. The solu- tion soon loses its dark brown colour, becoming pale yellow, and if the tint does not change after adding more potassium hydroxide, the treatment may be stopped, and the solution poured into water. The whole is now extracted with ether, and the residue left on dis- tilling off the ether is crgstallised three times from dilute alcohol. The ethyl ether melts a t a much lower temperature than the methyl ether, namely at 97". 02073 gave 10.99 C.C. of moist nitrogen a t 24' and 762 mm. N = 5.90. C,,H,,N02 require8 N = 5.57 per cent. Benzyl Ether of Bnthrapinoneoxime. The alcoholic alkaline solution of the oxime was boiled with the calculated quantity of beneylic chloride, the solution poured into water, and the benxyl ether extracted by agitation with ether; the residue left; on evaporating the ether was crystallised from alcohol. If the alcoholic solution is too concentrated, an oil seprates, which becomes crystalline after a time ; as these crystals are never quite pure, i t is advisable to prepare! a dilute solution, and induce crystal- VOL. T'XIX. G74 MARSH AND OARDNER: lisation by adding a crystalline fragment of the benzyl ether. The benzyl ether crystallises very well, and is easily soluble i n alcohol, ether, benzene, and chloroform. It melts at 82'. 0.1258 gave 0.3709 CO, and 0.0569 H,O. C = 80.40; H = 5.01. C21H,5N02 requires C = 80.51 ; H = 4-79 per cent.

ISSN:0368-1645    

DOI:10.1039/CT8966900068

出版商:RSC    

年代:1896

数据来源: RSC

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74 MARSH AND UARDNER: V III .- Researches on the Terpenes. V I . Products of the Oxidation of Camphene; Carnphoic acid and its Deriva t z'ves. By J. E. MARSH and J. A. GARDNER. IN the Transactions for 1891, p. 64, we describe the method em- ployed for the oxidation of camphene by nitric acid, by which we obtained camphoic acid, anew acid of the formula CIOH1406. I n this paper we give an account of some further experiments made with camphoic acid, and describe the isolation of other acids formed along with it by the oxidation of camphene; we also make some general observations as to the chemical nature of camphene, and its relationship to the terpenes, to camphor, and to camphoic acid. Camphoic acid. This acid was obtained in the way already described by heating camphene with nitric acid of sp.gr. 1.3 on the water bath ; the crude acid is best purified by crystallisation from hot nitric acid of sp. gr. 1-42, in which it is readily soluble, crystallising out almorjt completely on cooling. The melting point was wrongly given at 184!-185" in the former paper; we find, however, that the acid melts at a temperature approaching 200", whether crystallised from ether, from nitric acid, or from water, but the melting point is not quite exact as the substance begins to decompose before it melts ; thus a specimen of the acid crystallised from ether melted at 197-198", whilst another specimen twice crystallised from nitric acid melted at 19P, and after two further crystallisations from water it stiIl melted af 1 9 6 O , in each case decomposing at the same time.The specimen of highest melting point was that, obtained from anhydrocaraphoic acid, a compound described in this paper; prepared in this way, it melts and decomposes at 199--200°. A specimen of the acid obtained from anhydrocamphoic acid gave on analysis Found. Calculated for C1,,Hl4O6. 51.97 Carbon.. . . . . . . 52.1 per cent. Hydrogen . . . . . 6.19 6.0 9,PRODUCTS OF THE OXIDATION OF CAMPHENE. 75 Camphoic acid was also obtained by the oxidation of chloro- camphencphosphonic acid, CloHlaC1*P03H2, by means of nitric acid. This acid is produced by the action of phosphorus pentachloride on carnphene and subsequent treatment of the product with water ; i t was treated with nitric acid in the same way as described for camphene. The carnphoic acid obtained from it was crystallised from ether and analysed.It gave Found. Calcidsted for CloH,,OG. Carbon .......... 52.23 52.1'7 per cent. Hydrogen. ...... 6-39 6.08 ,, This acid also split up on distillation into carbon dioxide, and cam- p hopyri c anhydride. Camphoic acid has a sharp, acid taste, and is very soluble in water, alcohol, and ether, but less so in benzene or petroleum. I t is a tribasic acid, and forms salts with one, two, or three molecular pro- portions of base. A crystalline barium salt of the formula BaCIoH,,O6 was described i n the former paper; it had an acid reaction. Most of the salts of camphoic acid are soluble in water, but the copper and lead salts are almost insoluble. The sodium salt was not prepared, but on mixing weighed quantities of camphoic acid with two and three equivalents of caustic soda me found that the disodic camphoate is acid while the trisodic camphoate is alkaline.The triammonium camphoate is prepared by dissolving dry cam- phoic acid in dry ether and passing in dry gaseous ammonia. The precipitated salt must be collected rapidly and placed in a dry atmosphere over sulphuric acid, as it is deliquescent and turns yellow on exposure to moist air. It is obtained i n this way as a white, friable mass, melting at 198-199O and at the same time decomposing. A determination of nitrogen gave Calculated for Cslculated for Found. CIOH*106\NH4)3' 40H1206(NH4)2* N ....... 13.51 14.94 10.6 per cent. This salt is very soluble in water, and on evaporating the solution, ammonia is evolved and the monoammonium salt formed; this separates in white, glistening crystals, which melt a t 208-210°, and at the same time decompose.A determination of nitrogen gave the following result. Calculated for Found. C10HI130ti.NH4. N ........ 5-86 5-67 per cent. The copper salt is obtained by boiling a solution of sodium camphoate with copper sulphate, when it separates as a pinkish preci- pitate, whioh redissolves on cooling the solution. The triplumbic a 276 3IARSH ASD GARDNER : camphoate is obtained as a white precipitate on adding lead acetate or lead chloride to a solution of sodium camphoate. The precipitate when dried at 100' gave on analysis Calculated for Fo un (1. Pb,(C,OH,,O6)2. Lead.. .... 56.5 57.7 per cent. A specimen dried at t203 gave lead 58.3.&hy dr ocanapho ic acid, C loH,20,. This acid is obtained by the action of acetyl chloride on camphoic acid. When camphoic acid is heated with ncetyl chloride, i t slowly (lissolves with evolution of hydrogen chloride ; the solution is then evaporated to dryness, and the residue crptallised from ether. It crystallises in large, trimsparent plates from ether or ethylic acetate, melting and decomposing at 205". Its formula, CI0Hl2O5~ is that o E camphoic acid less 1H20. On analysis it gave Xound. Calculated for CloH120,. Carbon.. ........ 56-51 56.6 per cent. Hydrogen ....... 5-93 5.6 ,, Anhydrocamphoic acid has a sweet taste very different from the sharp acid taste of camphoic acid. It is ouiy slightly soluble in benzane, chloroform, petroleam, or cold water ; i t is readily soluble in hot water, and on cooling crystallises out in part unchanged ; part, however, is hydrolysed.It crystallises best from dry ether or from ethylic acetate, and is precipitated from its solution in ether 011 the addition of light petroleum. It dissolves in sodium carbonate, and is precipitated unchanged by the addition of hydrochloric acid. When anhydrocamphoic acid is boiled with water preferably con- taining a little acid, it is gradually hydrolysed with production of camphoic acid. The camphoic acid obtained in this way melts a$ 199--200' with decomposition. Theanalpis of it is given on page 74. It was stated in the former paper that when camphoic acid is dis- tilled it undergoes decomposition yielding carbon dioxide, water, cam- phopyric anhydride, and isocamphopyric acid. CIOHNO~ = CgH120, -k H20 -k Go,, CioHi,06 = CgH1401 + (302.When anhydrocamphoic acid is heated above its melting point, it decomposes intb camphopyric anhydride and carbon dioxide. C10H1205 = CgHi203 + Co2. The reaction appears to be quantitative, bat it is difficult t o obtain an exact result owing to the sublimation of thc camphopyric an-PRODUCTS OF THE OXlDATION OF CAMPHENE. 77 hydride. A weighed quantity of anhgdrocampboic acid was heated in a tube connected with a drying tube and potash bulbs ; the tube was heated in a sulphuric acid bath above the melting point of the substance until the effervescence ceased, and the decomposition appeared to be complete ; a current of air was then drawn through the apparatus.The experiment gave Total loss of weight of anhydro- Found. CaIculated. camphoic acid .............. 20 20 per cent. Gain of weight of drying tube. .. 1 0 9 7 (carbon dioxide) 17 20 11 Gain of weight of potash bulbs ............ The loss of weight in excess of the amount of carbonic acid appeared to be due to snblimation of the anhydride, some of which may have found its way into the drying tube. Anhydrocamphoic acid is a monobasic acid, neutralising one equivalent of caustic soda; but the point of neutralisation is difficult to hit, owing to the rapid hydrolysis of the anhydride by the action of caustic soda, the colour produced on the iadicator, phenol- phthalein, rapidly disappearing as the soda is taken up. The relation subsisting between camphoic acid and anhydro- camphoic would be that represented by the formuh H H Camphoic acid.Anliydrocamphoic acid. Canipltopyric acid, cis-. When camphoic acid is distilled, camphopyric anhydride, CeHI2O3, is obtained; this, when dissolved in hot caustic soda, is converted into camphopyric acid, C,Hl*O,. Camphopyric anhydride is also obtained by heating anhydrocamphoic acid above its melting point ; further, if camphoic acid is heated above its melting point, it undergoes decomposition, with loss of carbonic acid, but without appreciable loss of water if the temperature be not allowed to rise much above the melting point of the substance. In this may, the acid is produced directly from camphoic acid, the reaction taking place thus : C1oH& = CO, + CgHlt04. The product thus obtained dissolved almost entirely in cold solution of sodium carbonate, and the precipitate produced by hydrochloric acid after two crystallisations from water melted at 203-204O.It contains some mesocampho- pyric acid, a substance to be mentioned later (p. 79). Carnphopyric acid is a dibasic acid, and requires two molecular78 MARSH AND GARDNER: proportions of sodium hydroxide for neutralisation. 0.186 grnm acid required 10 C.C. of standard sodium hydrate ( 1 C.C. = 0908 NaHO) for neutralisation (calculated for dibasic acid 10 c.c.). It closely resembles camphoric acid as to the solubility of its salts, they being in general soluble in water, but the lead and copper salts, like those of camphoric acid, are insoluble in water, and are precipitated on adding a soluble lead or copper salt to a solution of the sodium salt of the acid.The lead salt thus obtained as a white precipitate was analysed after being dried at 110". Found. Calculated. It gave Lead .. . ... .. 52.5 52.9 per cent. The sodium salt was prepared and analysed; it is extremely soluble in water, and, on evaporating, the solution is left in rz syrupy condition, but it can be crystallised from a mixture of ether and alcohol. After drying at 120°, it gave Found. Calculated. Sodium.. . . . . 19.5'7 20.00 per cent. Canaphopyric Anhydride, cis-. This compound, described in sl former paper, is formed by distil- ling camphoic acid, by heating anhydrocamphoic acid above its melting point, and also by the action of acetyl chloride on cis-cain- phopyric acid; the yield in the last case is over 90 per cent.It is also formed by the action of water on camphopyryl chloride. The analogy between camphopyric acid and camphoric acid is also borne out by the nature and modes of production of their anhydrides. The two anhydrides are very similar in appearance and in properties; they are both very stable with regazd to the action of water ; they may both be crystallised from water unchanged ; they are both vola- tile at looo, and may be sublimed a t this temperature, and they are both volatile in steam. In one point, however, they differ, the melt- ing point of camphoric anhydride being higher, whilst that of cam- phopyric acid is lower than the melting points of their respective acids. Camphopyric acid, m. p. 209". Camphoric acid, m.p. 185'. Camphopgric anhydride, rn. p. 178". Ce.mphoric anhydride, m. p. 220*. Cumphopyryl chloride, C,,H,,O,Cl,.- -When camphopyric acid is treated with phosphorus pentachloride, it gives the acid chloride C,,H,,02C12 ; this is best obtained by mixing camphopyric acid with a slight excess of the pentachloride in a mortar, the acid being added gradually, and the whole well stirred ; in this way, the formation of anhydride is avoided. The oxychloride of phosphoras is then din-PRODUCTS OF THE OXIDATION OF CAMPHENE. 79 tilled off uuder ordinary pressure, and the campbopyry 1 chloride under diminished pressure ; it comes over at 125-130' under 13 mm. pressure. The above method is also satisfactory in the preparation of camphoryl chloride from camphoric acid.Camphopyryl ch1oride:is a colourlesu liquid, resembling camphoryl chloride in smell, reacting slowly in cold water, but readily soluble in and Iydrolysed by hot water ; it is only slowly acted on by sodium hydrate sointion when cold. The amount of sodium hydrate required to neutralise the acids formed on hydroIysis of camphopyryl chloride was determined by dissolving the chloride in standard sodium hydroxide in excess, the excess of sodium hydrate being determined by standard nitric acid. It was found that one molecular proportion of camphopyryl chloride required 3.86 (theory 4.0) molecular propor- tions of sodium hydroxide. The chlorine was also determined by titration with standard d v e r nitrate solution, using potassium chro- mate as indicator. Found.Calculated. Chlorine ........ 31.1 31.8 per cent. Action of Water o n Caniphopyvyl Chloride.-It was found by Marsh (Proc. Roy. Xoc., 1890,47, 6 ) that when the acid chloride of ordinary dextrocamphoric acid was treated with boiling water, it was converted into a mixture of the anhydride of dextrocamphoric acid and a new camphoric acid which was found to be lavorotatory. This acid was readily separated from the anhydride of the dextro-acid, with which i t was mixed, by treatment with a cold solution of sodium carbonate. The relationship of these two camphoric acids to oiie another led Marsh to consider one of them, namely, the dextrorotatory, as the cis-, and the laevorotatory as the trans-modification, corresponding to Baeyer's cis- and tm~ns-hydrotei.ephthalic acids.Shortly before the publication of Marsh's paper, Professor Friedel had announced the discovery of the same laevocamphoric acid which he had obtained from the long known mesocamphoric acid. It then appeared that rnesocamphoric acid was nothing else but a mixture of the dextro- and Iavo-camp horic acids. 21 esocamphopyric acid. When camphopyiyl chloride is treated with boiling water, it does not behave quite in the same way as camphoryl chloride, but the whole of the chloride readily goes into solution, and is hydrolysed ; the acid was obtained from this solution, the yield beiiig theoretical. It was found to be quite different from the original camphopyric acid, and subsequent examination proved it to be a mixture of the original acid, which we call the cis-modification, with a new isomeric80 BihRSH AND OARDNER: acid, trans-camphopyric acid.This mixture of acids we call meso- camphopyric acid to recall its analogy to mesocatnphoric acid. The mesocamphopyric acid. crystallises well from water, having all the appearance of a single substance ; its melting point, however, is not quite constant, varying betwoen 160' and 170'. This acid appears to be identical with the acid which we formerly described as isocam- phopyric acid produced along with camphoppric anhydride by the distillation of camphoic acid; it is also produced when camphoic acid is heated just above its melting point, in which case there is excess of the ordinary cis-camphopyric acid produced. C'amphopyric acid, trans-. Mesocamphopyric acid, when treated with acetyl chloride, is sepa- rated into its constituents, the cis-acid being converted into anhy- dride, while the trans-acid is left unaltered, and the two can then be separated by the action of a solution of sodium carbonate, which dissolves the trans-acid and IeaTes the cis-anhydride unaltered.The acid so obtained, after a second treatment with acetyl chloride, mas crystallised from water. I t melted at 190-191O. It was analysed and gave Found. Calculated for CsH,404. Carbon .......... 57.7 58.0 per cent. Hydrogen.. ...... 7.7 7.5 9 7 A better way to obtain the trans-camphopyric acid is to leave camphopyryl chloride exposed to moist air for some hours, I n this way tho liquid becomes converted into a dry, white, crystalline mass consisting of a mixture of the tram-acid with the anhydride of the cis-acid. The two are then separated by treatment with a solution of sodinni carbonate. On precipitating the sodium carbonate solutioii by hydrochloric acid and crystallising from water, the acid is obtained melting at 191".The meso-acid was prepared synthetically by mixing equal weights of the cis- and trans-acids, and crystallising from water; it is obtained thus as a homogeneous, crystalline substance, melting between 163" and 170". The melting points of the three campho- pyric acids are thus closely analogous to thotJe of the three corrc:- sponding camphoric acids, the trans-acid in each case melting at a lower temperature than the cis-, and the meso-acid lower than either of its constituents. Chlorocamphopyryl Chloride.In preparing camphopyryl chloride by the action of phosphorus pentachloride on camphopyric acid, we found that if the pentachlo-PRODUCTS OF TEE OXIDATION OF CA4XPHEXE. 81 ride is in excess and the mixture is heated on the water bath, the acid chloride produced contains more chlorine than is required by the formula C,H,,O,CI,; thus a specimen prepared in this way and distilled under diminished pressure at 1.32-133" was analysed, the chlorine being estimated by Carius' method. It gave Found. Calculated for CgHI2O2C1,. Chlorine ......... 32.9 31.8 per cent. ......... - ,, 33.1 9 ) T t was suspected that, by the action of heat on the camphopyrjl chloride in presence of excess of pentachloride of phosphorns, chlorine is substituted for hydrogen, as was found by Marsh to occur in the case of camphoric acid under similar circumstances (Proc.Roy. SOC., Zoc. cit.). Accordingly camphopyric acid was treated in order to produce chlorocamphopyryl chloride in the same way as camphoric acid was treated to produce chlorocamphoryl chloride. Eight g r a m s of camphopyric acid were heated with 33 grams of phosphorus pentachloride in a flask on a sand bath, the flask being provided with a reflux condenser; hydrogen chloride was evolved, and the product became liquid. After about seven hours' heating, the evolu- tion of hydrogen chloride had practically ceased, and, on cooling, the liquid was poured off from the excess of pentachloride, which had crystallised out. It was distilled a t first under ordinary pressure, when it began to boil at So, the temperature rising slowly, showing the presence of phosphorus trichloride along with the oxychloride.The substance was then distilled under 15 mm. presBure, when it boiled at 142'. The chlorine was de- termined. It is a colourkss liquid. Found. Calculated for Cg'Fz1102C13. Chlorine ......... 41.7 41.3 per cent. It thus appears that camphopyric acid undergoes the same reaction as camphoric acid, as expressed by the following equations. ~II)H,,O~ -+ 3PC1, = C,H,,C1302 + PCl, + 2POC13 + 3HC1. C ~ H ~ ~ O J + 3PC1, = CgHl,C1302 + PCls + 2POC13 + 3RC1. Chlorocamphoryl Chloride. As the notice in the Proceedings of the Royal Society with regard to this substance was very brief, i t may not be out of place here to give some further details about it.Camphoric acid, mixed with about 49 times its weight of phos- phorus pent.achloride, was heated i n flr flask provided with a reflux condenser on a sand bath for 17 hours ; the trichloride and oxychlo- ride of phosphorus were then dktilled off under ordinary pressure,82 MARSH AND GARDNER and the residue fractionally distilled under diminished pressure- After three distillations, a liquid was obtained boiling at 145- 148O under pressure (11 mm.), which solidified on cooling. The chlorine was determined in this specimen. Calculated. Found. C16H13C1302. Chlorine ....... 39.37 39.23 per cent. )) 39.27 7 ? The amount of the pure substance so obtained was 70 grams from 100 grams o€ camphoric acid, 40 grams of less pure substance being also obtained. Chlorocamphoryl chloride is a nearly colourless, crjstalline solid, melting when the flask containing it is held in the hand at a temperature of about 28"........ - Chlorocamphoric Anhydride. When chlorocamphoryl chloride is poured into seven or eight times its weight of boiling water, it remains a t the bott.om of the vessel in the for= of an oil, which gradually becomes solid; the solid xas washed with sodium carbonate solution, in which very little dis- solved, and, as i t gave off hydrogen chloride on drying, it was again treated with hot water, then washed with sodium carbonate, and dried. From 70 grams of chlorocamphoryl chloride, 50 grams of chlorocamphoric anhydride were thus obtained, or over 90 per cent. of the theoretical yield. The substance, crystallised from benzene, melted at 233-234" ; mother specimen melted at 235'.The chlo- rine was estimated. Calculated. Found. Cl,Hl,C~O,. Chlorine ......... 16.22 16.39 per cent. If chlorocamphoryl chloride is boiled with water until it is entirely cfissolved, camphanic acid is obtained on concentrating the solu- tion ; it separates at first as an oil, which crystallises after a time. I, a portion was dried a t 100' and analysed ; I1 is another specimen prepared in the same way. The crptals effloresce in the desiccator. Found. r--7 Calculated. I. 11. C10H1404- Carbon. ..... 60.25 60.31 60.60 per cent. Hydrogen ... 7.07 7-27 7.07 ,, The barium salt gave 25.4 per cent. Ba, found. 9 , 9 9 25.8 ,, ,, calculated. The salt is completely soluble in water and on slow evaporation gives crystals.PRODUCTS Oh' THE OXIDATIOX OF CAXPHEXE.53 Asclian has recently described the production of chlorocamphoric anhydride in another way, and has shown that it is converted into camphanic acid by boiling with caustic soda. We may be permitted tc say that our work above described on chlorocaniphoric chloride, chloi~ocaniphoi~ic anhydride and camphanic acid, was done during 01- before th(! year 1889. Ch 1 oroca my hopy r ic A nh y drid e . Chlorocamphopyryl chloride is only very slowly acted on by water; if, however, it is dissolved in ether and this solution is allowed to remain in contact with water, large, colourless crystals gradually form between the ethereal and aqueous layers. These crystals are nearly insoluble in light petroleum or benzene, more soluble in ct'ner and still more so in chloroform.They melt a t 288-229' and gave the following rasults on analysis. Calculated. Found. C9HllC103. Carbon ........ 53.04 53.33 per cent. Hydrogen ...... 5-80 5.44 ,, C hloriiie ....... 17-50 17.50 ,, The substance is chlorocamphopyric anlijdride analogous to chlorocamphoric anhydride. We: have not yet obt.ained sufficient of the substance to determine whether an acid analogous to camphanic acid is produced from it, but we have evidence that the acid obtained by dissolving chlorocamphopyryl chloride in sodium hydroxide is not a monobasic lactonic acid like camphanic acid, but a dibasic hydroxy- acid. This point, however, we must reserve, and we hope to make it the subject of a, future communication t o the Society.Camphopyranilic acid. Camphopyric acid forms a.n anilic acid, again closely annlogons to the anilic acid from camphoric acid. Camphopyric anhjdride was heated with aniline and the melt, which became solid on cooling, after being washed with di1ut.e hydrochloric acid to free i t from aniline, was crystallised from alcohol. Camphopyranilic acid is then obtained in colourless crystals, melting at 212", of the formula "9HlACooH C0*NH*C6H5. It is soluble in soda and reprecipitated by hydrochloric acid. Found. Calculated. Carbon ........ 68.84 68-96 per cent. Hydrogen.. .... 7.39 7.23 ,, Nitrogen ...... 5-41 5-36 .,84 MARSH AND GBRDSER: Action of Hydmgen Iodide on Camphopyric acid. Sixteen grams of camphopyric acid were heated with 32 C.C. of hydriodic acid of sp.gr. 1.8, and a little red phosphorns in sealed tubes ; the action is very slow, the tubes containing some crystalline matter after prolonged heating. They were heated in all for 40 hours at first> at 220°, and finally to 280'; t*he contents of the tubes were then liquid. The liquid was made alkaline with soda and distilled in steam, when a pale yellow, volatile oil came over, this was separated, dried with calcium chloride, and distilled from sodium, when moat of it came over a t 105-125". On redistilling this fraction, it boiled at 105-115'; the amount was 2 C.C. On analysis it gave Found. Calculated. C,H16. Carbon ........ 85.75 85.71 per cent. Hydrogen.. .... 13.84 14-24 ,, By analysis alone it is not possible to distinguish between Lexa- hydro-xylene, C8H16, and hexahydrotoluene, C7HIb, or any other hydro- carbon of the series.The vaponr density, however, showed that the substance was hexahydro-xylene. Weight of substance taken.. .... Volume of air.. ................ Barometer, 761 mm. Hence density (H = 1) ......... Density of hexahydro-xylene (cal~ulat~ed). ... 0.0891 gram. 18.75 C.C. 66.3. Temperature, 13' C. 56 .. hexahydrotoluene ( .. ).. .. 49 The substance was also nitrated; for this purpose 14 C.C. of the hexahydro-xylene was heated with 25 C.C. of a mixture of 2 parh of strong sulphuric acid and 1 part of nitric acid. As nothing separated on cooling, the mixture was poured into water, when, on standing, fine crystalline needles were deposited ; these, after being washed with water and crjstallised from alcohol, melted at 178', and mere evidently trini trometaxy lene.Hence the reduction of camphopyric acid by hydrogen iodide yields hexahydrometaxylcne. Furtlter Products of the Oxidation of Camphene. Among the other products of the oxidation of camphene by nitric acid, we obtained terephthalic acid, carnphoric acid, and succinic acid, besides other substances, the nature of which we have not yet determined. After camphoic acid has been separated from the crude product of oxidation, a syrupy mass is left; most of this dissolves on treating i t with ether, leaving terephthalic acid as an insoluble whitePRODUCTS OF THE OXIDATION OF CAMPHENE. 55 powder. This mas converted into its dimethylic salt by treatment with phosphorus pentachloride and methylic alcohol.On crystal- lising the product from methylic alcohol, it mejted a t 140-141'. When tlhe etheral solution of the syrupy mass was shaken up with sodium carbonate solution, a considerable amount was left, dissolved in the ether, having apparently no acid properties, and on separating the ethereal solution, n yellow oily residue was left. On attempting to distil this yellow oil, it suddenly and violently decomposed, after removal of the flame, evolving gas and leaving a small qaa.ntity only of carbonaceous residue in the flask. The sodium carbonate solutions were acidified, bat no definite substance could be obtained from them ; on distilling the product which separated, however, a large quantity of camphopyric anhydride was obtained, hence the oily matter probably still contained cam- phoic acid.Besides the campbopyric anhydride, an oil was ob- tained on distillation; this was volatile in steam, lighter than water, a,nd had a camphorous smell. I t was shaken out with ether and dist+illed. It boiled at about 250°, and gave on analysis Carbon .. .... .. 68.46 68.57 per cent. Found. Calculated. C,H,20,. Hydrogen.. . . . . 8-76 8.57 ,) It appears to be saturated as i t does iiot take up bromine, One gram was heated at 100' with baryta water, and the barium salt obtained was converted into the sodium salt by means of sodium carbonate ; the sodium salt, after having been freed from carbonate by solution in alcohol, was analysed. Calculated. Found. C,H13Na03. Sodiam.. .. . . . . 13.0 12.7 per cent. The oil thus appears to be a lactone, but it was not obtained in mfficient quantity to enable us to examine it further.The presence of succinic acid was suspected, by its characteristic taste, in the crude crystals obtained from the mother liquors after separation of the camphoric acid. It was isolated by suitable means, and, after crystallising from water, it melted a t 186". It gave a bArium salt insoluble in ammonia ; this was analysed. Found. Calculated. Barium.. . . . . . . 53.67 54.15 per cent. Camphoric acid was obtained in small quantity from the crude crystalline csmphoic acid by treatment with acetyl chloride, and separated as anhydride from the anhydrocamphoic acid by snblima- tion at 100' or by treatment with water. After being purified by recrystallisation from boiling water, it was obtained sometimes i n86 MARSH AND GARDNER: small needles, sometimes in thin leaf-like crystals.The specimens from different samples of camphoic acid, varied somewhat in melt- ing point; one, prepared by sublimation melted at 204O, another., after recrystallisation from water, at 220-221', and another at 215-216'. Another specimen, obtained by treatment with watw, melted at 204-205' after recrystallisation from absolute alcohol. Several of these different samples were analysed. Found. r----h-- 7 Calculated for I. 11. 111. C:oH1403. C ......... 65.05 6-5-48 65.35 65.93 H . ........ 8.00 7.9 7.75 7.69 Another sample, melting at 215-216', was boiled for a long time with water, in which it gradually became more soluble ; after being allowed to remain for a long time, i t was concentrated to a small bulk, when white, glistening, crystalline leaves separated.These crystals had an acid reaction and melted at 182-186O. A small portion, on treatment with acetyl chloride, gave an anhydride melt- ing at 213". The acid was analysed, with the following results. Found. Calculated for CloU,60,. C .......... 59-71 60.0 per cent. H.. 8.29 8.0 7, ........ From this it appears that the product of oxidation of camphelie contains tt camphoric acid, but whether a new one or one already known it is impossible to say, as the quantity was insufficient t o determine its optical rotation or to purify it further. Theoretical Considerations. The hydrocarbon camphene, from which camphor, camphoric acid, and camphoic acid are derived, is n very stable substance, differing in that respect from the turpentines and citrenes.It appears to be a, saturated hydrocarbon, to contain no double linkings, whereas tur- pentine appears to have one, and citrene two double linkings. Wallach has shown that camphene does not form an additive compound with bromine, but a substituted compound, and our own work on the phosphonic and chlorophosphonic derivatives of camphene shows that the hydrocarbon readily forms substituted, but not additive compounds. Camphene, it is true, forms an additive compound with hydrogen chloride, and this circumstance appears to have led chemists to ascribe a, double linking to camphene. But hydrogen chloride and the halogen acids are not, like bromine, reagents specially characterised by their capability of saturating a double linking, although in certain cases they may do so.Hydrogen chlo- ride does not, for example, under ordinary circumstances, if at all,PRODUCTS OF THE OXIDATION OF CAMPHENE. 87 saturate the double linking in ethylene or in ally1 alcohol. Now, i f camphene contain no double linking, it must be constituted of a t least three closed rings, for a compound having ten carbon atoms derived from a fully saturated open chain formula Clr,Hn must, if i t remain saturated, close a chain for every pair of hydrogen atoms i t loses. If, then, camphene, CIOH166, is a, saturated hydrocarbon consti- tuted of three closed rings, in order to form camphene hydrochloride, CIOH&l, or camphor, C10H160, from it, one of the three closed rings must be broken, leaving two, and to forin camphoric acid, Cl0H,,OI OY camphoic acid, CIoHlrO6, two of the closed rings must be broken, leaving on17 one.Hence when hydrogen chloride acts on camphene we regard the union of the two, not as the saturating of a double liuking, but as the breaking of a ring formation. This is by no means an uncommon action of a halogen acid. Indeed the halogen acids are characterised by their power of breaking feebly united ring structures much more so than is bromine. For example, Frennd found that the trimethylene ring is readily broken by hydrogen iodide, but with great difficulty by bromine. Perkin also found that trimethylenedicarboxylic acid was not acted on by bromine at tho ordinary temperature, while substlitution took place on warming ; on fhe other hand, the r i n g is immediately broken by hydrobromic acid.Similar instances might be given in the case of other rings. If, then, camphene may be regarded ad constituted of several ring formations, we have next to consider the evidence as to the parti- cular nature of these rings. The production of camphoic acid from camphene, together with its relationship to camphoric acid and to hexamethylene, appears to throw light on this question. The close analogy of camphopyric acid to cainphoric acid, aud the production of hexahydrometaxylene from each of them, warrants us in assuming that both acids, and also camphoic acid, are substituted derivatives of hexamethylene. Now, since camphoic acid is not formed from camphor or from camphoric acid, it would appear that the cam- phene molecule is broken down in two ways : (1) to yield camphor and camphoric acid, (2) to yield camphoic acid, in both cases leaving a hexamethylene nucleus untouched. The forlnuls given by Marsh (Proc.Roy. Soc.: 1890, 47, 6) for camphor and camphoric acid represented them, if we disregard for the moment the position ob t h e methyl group, as follows- x2 H2C C H ~ CH.CH,-COOH .T H2C C H ~ CH*CH2 I L%n I \CO I i E n I v CH2 v H2C ring CH.CH2/ H2C CH-COOH CHZ Camphor. Camphoric acid.88 XARSH AND GARGNER: with a methyl group substituted for hydrogen in the hexamethylene ring. The most probable view of the constitution of camphoic acid appears to us to represent i t as a hexamethylene ring with two carboxyl groups replacing hydrogen attached to the same carbon atom, and oue carboxgl group replacing hydrogen attached to an adjacent carbon atom, with methyl replacing hydrogen in the ring, thus : CH, In order to derive the foregoing formule for camphor and for cam- phoic acid from camphene, we have tso explain the six carbon and five carbon rings of camphor and the six carbon ring of campboic acid, which it appears to us is necessarily different from the six carbon ring in camphor and in camphoric acid.We have, then, in camphene a pentamethylene ring and two different hexamethylene rings. These we cannot express by the ordinary cyclic formule. We have t o give to camphene a tridimensional formula, a formula in which the atoms are not regarded as situated i n a plane, but cn the surface of a sphere.Such formulae, which can only be imperfectly represented on paper, may be called spheric formulae to distinguish them from cyclic formula. They may be regarded as derived from triply-linked carbon atoms in the same way that Baeyer has repre- sented cyclic formulse as derived from doubly-linked carbon. Baeyer has derived cyclic formulee from doubly-linked carbon atoms, regard- ing the carbon atoms as not directly doubly linked, but indirectly through the intervention of other carbon atoms, as, for example, in his comparison of the hexahydroterephthalic acids with maleic and fumaric acids- H COOH Y c! H COOH \’ ‘i /\ t i c c c c P\ H COOH /\ H COOH In a similar manner we may regard spheric formulae as derived from triply-linked carbon atoms, the carbon atoms not being directlyPRODUCTS OF THE OXIDATION OF CAMPHENE.89 linked by thrze bonds, but indirectly by the intervention of other carbon atoms, thus (Fig. I) : FIG. 11, H H i C H H a formula made up of three hexamethylene rings. The formula we propose for camphene is derived from this triple hexamethylene spheric formula, thus (Fig. 11). By breaking the link marked a, we derive the formula of camphor ; whereas by breaking the two links marked p, and leaving the link a, we derive camphoic acid. In the first case, a pentamethylene and a hexamethylene ring are left, while when the links /3/3 are broken, a hexamethylene ring only is left, which is, moreover, different from the hexamethylene ring of camphor. Further, we represent turpentine or pinens by the same structure as camphene, omitting the link y, and introducing one double link- ing.The production of camphene from turpentine hydrochloride is readily explained by this hypothesis, which, we believe to be borne out by other reactions of turpentine and its oxidation products. The universally-accepted structure for citrene and cymene is also readily derived from that of turpentine by eliminating tbe linking 6, and from camphene by elimination of both and 6 links. The cam- phor and camphoric acid formulce, derived from the above camphene formula, differ from those proposed by Marsh in 1889 only in the position of the methyl group in the ring. Against those formule, no serious objection has been brought forward except that they do not account for the production from camphoric acid of trimethylsuc- cinic acid. But the formation of trimethylsuccinic acid appears to us to indicate such a complete breaking down of the camphoric acid molecule, that i t would not seem likely to have any more value for the determination of the formda of that compound than, for example, va. LXIX. H90 PRODUCTS OF TEE OXIDATION OF CARTPHICNE. the formation of methylsuccinic acid from tartaric acid or of alcohol from sugar has for determining the constitution oE tartaric acid 01' of sugar respectively. The formula now proposed €or camphor and camphoric acid, differ- ing, as we have said, from the earlier ones only in the position of methyl group, are represented below as derived from camphene. the A 1. 2. 3. 4. 5. 6. 7. 8. CH? Camphene. Campl1or. co (3x2 /\ I I \/ ca2 H2C CH-COOB CH,CH CH.CH,*COOH Camphoric acid. In conclusion, we believe that the formulm suggested in this paper account in a. simple manner for the principal facts relating to t'he temene and camphor groups. They account- For the conversion of turpentine, citrene, and camphor into For the conversion of camphor into carrncrol. For the conversion of turpentine into camphene and into citrene. For the oxidation of camphene to camphor and to camphoic acid. For the absence of double linkings in camphene, and €or the presence of one double linking in turpentine and two in citrene. For the production from camphoric acid of carnphanic acid, and campholactone. For the relationship of camphoric acid and camphoic acid to hexahydroisox ylene. For the general analogy of camphoric acid and camphopjric acid, and for the stereoisomerism manifested by them. cymene. Univemit y La bo ra toy y, Ozf o rd.

ISSN:0368-1645    

DOI:10.1039/CT8966900074

出版商:RSC    

年代:1896

数据来源: RSC

摘要:

91 1X.-The Action of Sodium Alcoholute on Aonidcs. By JULIUS B. COHEN, Ph.D., and WILLIAM H. ARCHDEBCOX, B.SC., The Yorkshire College. AT the meeting of the British Association in 1894 (Brit. Assoc. Bepoyts, p. 625) a communication was read by one of us on the constitution of the amides, containing a brief reference to the action of sodium methoxide on acetanilide. As this action appeared to us to have an important bearing on the constitution of the amides, we have studied it more fully, and now bring before the Society the results which we have obtained. If, to a solution of acetanilide in dry ether, powdered sDdium meth- oxide is added in molecular proportion, it dissolves ; but aEter the lapse of a few minutes, a voluminous crystalline compound is deposited, filling the liquid.This substance has the formula C,H,*NH*C O*CH3,CH3*ONa. Similar compounds have been prepared with ortho- and para,-aceto- toluidide and a- and p-acetonaphthnlide on the one hand and with sodium methoxide and ethoxide 011 the other. Benzanilide and form- anilide form similar compounds. With formylphenylhydrazide, however, no additive compounds are formed ; but the sodium appears to displace the hydrogen in the amido-groups. In the case of benz- amide, a fine granular compound is obtained, which appears to be a mixture of the alcoholate additive compound with sodium benznmide. With propionanilide, bntyranilide, diphenylacetamide, and ethyl- acefanilide no definite compounds have so far been obtained by this method. I n the case of propionanilide and bntyranilide such corn- pounds appear to exist in solution ; for if R little ether be added to either of fhese substances, sufhient to dissolve a fraction of the whole, the addition of the sodium alcoholate will at once produce a clear solution ; on evaporating the ether under diminished pressure.nothing separates out until the greater portion of the ether has gone, when crystals of the unchanged nnilide are deposited. Acetanilitle Sodium Metl~yZoxide, C6H,*NH.CO*CH,,CH3*ONa.-l.33 grams of acetanilide is dissolved in dry ether (complete solution is not necessary) and 0.54 gram of finely powdered sodium methoxide is added ; on shaking, a clear solution is obtained, but very soon n, pasty magma of needle-shaped crystals forms. The crjstals are collected, washed with ether, and di-ied over sulphuric acid in a vacuum.The substance forms a white, apparently amorphous mnss. It gave the following results on analysis. H 292 COHEN AND ARCHDEACON: THE ACTION OF I. 0.2455 gave 0.0942 Na2SOd. Na = 12.47. 11. 0.4359 ,, 0.1695 ,, Na = 12.59. 111. 002620 ,, 16.1 C.C. dry nitrogen at 13" and 770 mm. N=7.45, IV. 0.1890 ,, 0.372 COz and 0.1115 H,O. C = 56.98 ; H = 6-55. CgH,,NaN02 requires Na = 12.17 ; N = 7.40; C = 57.14; H = 6-35. I n some of the subsequent determinations, the sodium has been estimated by decomposing the compound with water and titrating with decinormal osalic acid, using phenolphthale'in as indicator. The above compound is quickly decornpofled by water and alcohol and also by boiling ether and acetone, which dissolve out the acet- anilide. It is also decomposed by acid chlorides, forming the methylic salt of the acid, sodium chloride, and acetanilide according to the equation C~HPNH.CO*CH,CH,.ON~ + *R'COCI = C6&aNH-CO*CH3 + NaCl + CH3*COOR'.If acetyl chloride is added to the calculated quantity of the sub- stance suspended in ether, meth;ylic acetate, sodium chloride, and acetanilide are formed; the latter was identified by decomposing it, with potash, into acetic acid and aniline, and by a nitrogen estimation. 0.1905 gave 17.5 c.a. moist nitrogen at 752 mm. and 16'. N == 10.48. CsHgNO requires N =3 10.37 per cent. From 2 grams of the sodium methoxide compound and 1.79 gram of benzoyl chloride, 1 gram of methylic benzoate, and 1.29 gram of acetanilide were obtained.On heating the compound in a stream of dry hyvdrogen for four hours to loo", methylic alcohol distils together with a little aniline ; the aniline was identified by converting it into the plstinochloride and analysing it. (C6H,*NH2)2,H2PLC16 requires P t = 32.66 per cent. Benzoyl chloride acts similarly. 0.294 gave 0.0955 Pt. The residue consisted for the most part of sodium acetanilide. 0.231 gave 15 C.C. moist nitrogen at 759 mm. and 13'. .CgHl2NNa0 requires N = 7.40 per cent. Further, the sodium acetanilide obtained in this way was treated with benzoyl chloride, when benzanilide, melting at 160°, is formed. The substance was analysed with the following result. 0.1745 gave 11.3 C.C. moist nitrogen at 21' and 760 mm. C1,H,,NO requires N = 7.11 per cent. The action of iodine on the sodium methoxide compound suspended in ether gives rise to a number of products, among which phenyl- carbarnine, acet-anilide, and iodoform were identified.Ethylic iodide yields ethyl methyl ether and acetanilide. Pt = 32.48. N = 7.65. N = 7-38,SODIUM ALCOHOLATE ON AMIDES. 93 The following compounds have been prepared in a manner similar to acetanilide sodium methoxide. Where the amide is but slightly soluble in ether, the sodium a.lcoholate has been added to the snb- stance suspended in the ether, well shaken, and then filtered or decanted. The clear filtrate, on standing, deposits crystals of the new compound. Acetanilide sodium ethoxide, (1,Ha*NH*CO*CH,.C2Hs.01\+a.-The preparation of this compound is identical with that of the sodium methoxide compound, and the substance is not distinguishable from the latter.0.283 required 13.9 C.C. decinormal oxalic acid. The following results were obtained on analysis. Na = 11.3 per cent. 0.2345 ,, 11.7 $ 9 9 ) Na = 11.4 ,, Cl0Hl4NO2Na requires Na = 11.6 per cent. Payace to to luidide sodium met h 0;. ide, C H3* C ,H4*NH*C 0 C H3, C H3*0 Na . Prepared as above from paracetoluidide, gave on analysis. 0,113 required 5.6.5 C.C. oxalic acid. Na = 11.74 per cent. CIoH,4N02Na requires Na = 11.33 per cent. Orf hoacetotoluidide sodium methoxide, CH3* C6Ha'NH.C 0*CH3, CH3* ONa, CloRI4NO2Na requires Na = 11-33 per cent. cr-Acetona,hthaZide sodium methoxide, CloH.I.NH.CO*CH3,CH,*ONa. 0.1705 required 7.8 C.C. oxalic acid. Na, = 10.52 per cent, This substance crystallises in brilliant, needle-shaped crystals.0.2875 required 11.6 C.C. oxalic acid. Na 9.3 per cent. C13H14N02Na requires Na = 9.6 per cent. Paracetotoluidide sodium ethoxide, C H3* C 6H4*NH* C 0 4 H3, C2H5* ONa 0.176 gave 0.0566 Na2S04. 0.1413 required 6.5 C.C. oxalic acid. Na = 10.4 per cent. Na = 10.6 per cent. Cl1HlaO,Na requires Na = 10.6 per cent. Od~oacet~toluidide sodizcm e t h x i d e , CH3*C6H4*NH*C 04 H3, C2H5*ONa. 0.1335 gave 0.0440 NhSO,. C11H16N02Na requires Nrt = 10% per cent. a-Acetonaphthulide sodium ethoxide, Cl,,H7*NH*CO*CH3,C2H5*OZITa. 0,4035 required 15% C.C. of oxalic acid. C I P H ~ ~ N O ~ N ~ requires Na = 9.1 per cent. /3- Acetonaph ta Zide sodium ethoxide, C loH,*NH* C 0*CH3, C2H5*ONa. 0.346 gave 0.1 Nhs04. CI4Hl6NO2Na requires Na = 9.1 per cent.Na = 10.6 per cent. Na = 9.0 per cent. Na = 9.3 per cent.94 COHEN AND ARCHDEACON: THE ACTION OF Benzanilide sodium ethoxide, C6H5*xH*C o*c, H5, C2H6*ONa. 0.3040 required 12.1 C.C. oxalic acid. Na = 9.1 per cent. C I ~ H , ~ N O ~ N ~ requires Na = 8.7 per cent. Formanilide sodium ethoxide,( C6H5.NH*C OH),, C2H6.0Na.-If sodium metboxide in molecular proportion is added to formanilide dissolved in ether, crystalline nodules of the new compound are deposited on the sides of the flask and the contents eventually become nearly solid. The following are the results of two analyses of the sodium et hoxide compound. The same thing occurs with sodium ethoxide. 0,398 required 13.1 C.C. oxalic acid, Na = 7.8 per cent. 0.296 ,, 9.6 ,, ,7 N = 7.5 ,, C6H5*NH*COH,C2H5*ONa requires Na = 12.2 per cent.(C6H5.NISI.COH)2,C2H~~Na ,, Na = 7-4 ,, From this it would appear that in the case of formanilide, 2 mols. This might take place in the combine with 1 mol. of the alcoholate. Action of Sodium Ethoxide on Benzamide. In this case, a fine granular precipitate is obtained, which appa- i*ently has a constant composition, but this does not correspond with that of any definite compound. It might be a mixture of equal quantities of the additive compound and sodium benzamide. The action is evident,ly of a different order from that previously described. Three different preparations gave the following results. I. 0.196 required 12 C.C. oxalic acid; Na = 14.1 per cent. TI. 0.1785 ,, 11.1 C.C. ,, Na = 14.3 ,, 111. 0-1945 ,, 12 ,, 7 7 Na = 14.2 ,, C6H5*CO-N~z,CeH,*ONa requires Na = 12.1 per cent.C6H5*COoNHNa requires Na = 16.1 per cent. Action of Sodium Ethoride and Sodium LWethoxide on Diphenyl- acetanxide. Diphenylacetamide dissolves readily in ether, but on the addition of the alcoholate very little of the latter appears to pass into solu- tion; the clear filtrate gives only a slight, flocculent deposit on standing, and on evaporation in a vacuum, unchanged diphenyl- ace t amide separates.SODIUM ALCOHOL-!TE ON AMIUES. 9 5 Action of Sodium Ethoxide and Methoxide on Ethy1nt:etanilide. The same result was obtained as in the case of diphenylacetamide. On the addition of sodium methoxide to the ethereal sohition of the amide, none of the alcoholate appeared to dissolve. Sodium etlioxide was rather more soluble ; b u t in neither case did the ethereal solu- tion, on standing or on evaporation, give any indication of a crystal- line additive compound. Action of lSlodium Ethoxide on Fos..my~henylhydl.cceide.On adding sodium ethoxide to formylphenylhydrazide a yellow solution is obtained, from which an orange-yellow compound is deposited; in the dry state this is of a light ochre colour. 0.0788 gave 0.0623 of NaJ3Oa; Na = 25.6 per cent. C7H,N20Na2 = 25.5 per cent. Apparently, this substance has the formula C,H,*NNa*NNa*COH. The formation of additive compounds of the acetyl derivatives of aniline, the toluidines, and naphthylarnines with sodium methoxide and ethoxide would indicate the presence of an unsaturated group in these amides. Claisen has shown that such additive compounds are formed i n the case of the ethereal salts, and that numerous condensations of these salts with compounds containing the group C‘H2*C0 occur in this manner according to the following equations.I I 0 /ONa -C? + Na.0C2Hj = -C-OC,H,; ‘OR \OR ONa + C2Ho*OH + &OH. ONa 1 1 -CLOC,H, + CH2*C0 = -C< \OR ‘Q-QO Applying this idea to the acetyl derivatives we may have the addition of the sodium alcoholate taking place in one of the following ways. PormuIa I. R’*NH*Y:O + Na*OC2H, = R’*NH*$l<ON2a OC Hj. , CH3 CH3 Formula 11.96 EWAN : THE ELECTROLYTIC CONDUCTIVITY The second formula is the one which appears to us to agree best with the properties of the substance. We have shown that alcohol is given off from the additive compound of acetanilide with sodium methoxide on heating, and that sodium acetanilide is formed.This reaction is confirmed by the experiments of Seifert (Bey., 1885, 18, 1358), who prepared fiodium acetmilide by evaporating to dryness an alcoholic solution of sodium ethoxide and acetanilide. Moreover, there is no doubt, considering the formation of alkyl- anilides by the action of akylic iodides on sodium acetanilide, that the sodium atom is attached to the nitrogen atom. The formation of this sodium compound from acetanilide, sodium methoxide, by heat- ing it, would be difficult to explaiu by the first formula. This being the case, it would appear probable that acetanilide itself has thd formula CsHo-N: C (OH)*CH,. The fact that diphenylacetamide and ethylacetanilide do not appear to form analogous cornpounds is then easily explained, for these two compounds contain no replaceable hydrogen, and cannot therefore form a hydrosyl group. We do fiot, of course, lose sight of the possibility of a tautomeric change taking place at the moment of formation of these addition compounds, for, as Claisen has pointed out, questions of tautomerism cannot be satisfactorily decided where chemical changes are involved. An attempt to solve the problem by the electrical conductivity of the acid amides, kindly undertaken for us by Dr. Ewnn, is desci-ibed by him in another communication.

ISSN:0368-1645    

DOI:10.1039/CT8966900091

出版商:RSC    

年代:1896

数据来源: RSC

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96 EWAN : THE ELECTROLYTIC CONDUCTIVITY X.-Note o n the Electrolytic Conductivity of Fo~rn- an ilide and Thioforrnaiailide. By THOMAS EWAR’, B.Sc., Ph.D. IT was thought possible that the electrolytic conductivity of the aqueous solutions of the amides might throw some light on their structure, and at Dr. Cohen’s request I examined some of them from this point of view. The majority, however, are too sparingly soluble in water to allow of measurements being made, whilst others are de- composed by the water too rapidly. The following numbers were obtained with formnnilide. The measurements were made at 2 5 O , and as rapidly as possible, as the Conductivity increased on standing. p is the molecular conductivity in reciprocal Siemen’s units, pl and refer to two different samples of formanilide which were examined.OF FORMANILIDE AND THIOFORRIANILIDE. 97 Concentration (litres containing 1 gram mol.) v.Pl* pz. Mean p . k x 10 0.026 0.027 04265 5.6 20 0.031 0-034 0.0325 4.2 40 0.040 0.046 0-0430 3.7 80 0.058 0.068 0.0630 3.9 160 - 0.101 0.101 5.1 poo = 355 (approximately). A comparison of the value of 32 above found with its value for- acetic acid (180000 x lO-'O) shows that formanilide possesses only extremely feeble acid properties, and it is not surprising that its sodium salt is, as is shown by the following experiment, decomposed in aqueous solution almost completely into caustic soda and form- anilide. 2 C.C. water and 20 C.C. NllOO NaOH solution weye mixed ; con- ductivity of the mixture = 0.0169. 2 C.C. NjlO formaailide solution and 20 C.C.N/100 NaOH mixed ; conductivity of the mixture = 0.0167. A considerable decrease in the conductivity would have occum-ed if any appreciable quantity of salt had been formed. Thioformanilide, C,H,*NH*CSH, is very slightly soluble in water (the strongest solution obtainable was N/400), and i t decomposes rather rapidly into phenylcarbamine and sulphuretted hydrogen. Its sodium salt appears to exist in aqueous solution. 0.0685' gram of thioformanilide was dissolved in 4 C.C. of 51N/100. NaOH, and the solution made up to 102 C.C. (= N/50). The molecular conductivity of this solution was 180*0 at 25" ; the molecular con- ductivity of N/50 NaOH at 25' = 217.8. The quantity of thioform- anilide taken was equivalent to one quarter of the caustic soda, so that, assuming that the whole of the thioformanilide was converted into sodium salt, and that both it and the caustic sodaare completely dissocinted in N/50 solution, the conductivity of the solution may be calciilated as follows. r = pxa + QpoH + hciH6xs, = 49 + 2.170 + i . 3 5 = 185, The salt decomposes in the same way as the free thioformanilide.

ISSN:0368-1645    

DOI:10.1039/CT8966900096

出版商:RSC    

年代:1896

数据来源: RSC