摘要:

J 0 U R N A 1, OF THE CHEMICAL SOCIETY, TRANSACTIONS. A. CHASTON CHAPMAN. A.W. CROSSLEY C.M.G.,D.Sc.,F.R.S. M. 0. FORSTER D.Sc. Ph.D. F.R.S. A. :HARDEN D.Sc. Ph.D. F. R.S. T. A. HENRY D.Sc. C. A. KEANE D.Sc. Ph.D. G. 'r. MORGAN D.SC. F.R.S. J. C. PHILIP O.B.E. D.Sc. P11.D. W. J. PoPE,C.B.E.,M.A. D.Sc.,P.R.S. F. L. PYMAN D.Sc. Ph.D. A. SCOTT M.A. D.Sc. F.R.S. S. SMILES O.B.E. D.Sc. F.R.S. J. F. THORPE C.B.E. D.Sc. Ph.D., F. R. S. 6bifD.r : J. C. CAIN D.Sc. S&-6lF;bitar : A. J. GREENAWAY. &&atlmf %?snb.-&bifiYr : CLARENCE SMITH D.Sc. -~ 1918. Vol. CXIII. LONDON: GURNEY & JACKSON 33 PATERNOSTER ROW E.C.4. 1918 Abstractors of the JournaZ of the Society of Chemical Industry, who have contributed to this volume. J.F. BRIGGS. T. F. BURTON B.Sc. L. A. COLES. W. F. FREW. H. J. HODSMAN. J. H. JOHNSTON. C. A. KING. J. H. LANE. C. A. MITCHELL. B. NORTH. A. B. SEARLE. A. SHONK. F. C. TIIOMPSON. PRINTED IN GREAT BRITAIN BY RICHARD CLAY & SONS LIMITED, BRUNSWICK ST. STAMFORD ST. S.E. 1 AND BUNGAY GUFFOL CONTENTS. PA.PERS COMM TJNICATED TO THE CHEMICAL SOCIETY. PAGE I.-n4andeliminohydrin. By JOHN EDWIN MACKENZIE . 11.-Amidine Salts and the Constitution of the so-called Imino-lnydrins. By HAROLD GORDON RULE . 111.-The Preparation of a-Kaphtholphthalein. By EMIL .ALPHONSE WERNER . 1V.-The Nitration of 5- and 6-Acetylamino-3 4-dimethoxy-henzoic Acids and 4-Acetylaminoveratrole. By JOHN LIONEL SIMONSEN and MADYAR GOPALA HAU V.-Studies in Phototropy and Thermotropy.Part VIII. Cinnamylideneamines. 2 4-Dihydroxybenzylideneamines. By L~LFRED SENIER and PATRICK HUGH G-ALLAGHER . V1.-Studies on the Sulphonntion of P-Naphthylamine By ARTHUR GEORGE GREEN and KAPILRAM H. VAKIL . VI1.-The Effect of Temperature and of Pressure on the Limits of Inflammability of Mixtures of Methane and Air. By -WALTER MASON and RICHARD VERNON WHEELER . V1II.-The Relation of Position Isomerism to Optical Activity. :Part XI. The Menthyl Alkyl Esters of Terephthalic Acid m d its Nitro-derivatives. By JULIUS BERENU COHEK and 1X.-Nitro-derivatives of isoOxadiazole Oxides and of iso0xa-By ARTHUR G. GREEN and FREDERICK MAURICE X.-The Mercury Ammonia Compounds. Part I. By MURIEL XI.-" Spark-lengths " in Hydrocarbon Gases and Vapours.By XU.-Vacuum Enlance Cases. By BERTRAM BLOUNT and WILLIAM H. WOODCOCK . XIIT ,-The Constitution of Carbamides. Part V. The I~echanism of the Decomposition oE Urea when Heated in Solution with Alkalis and with Acids respectively. The Hydrolysis of Metallic Cyanates. By EMIL ALPHONSE WERNER . X1V.-Di-N-butylaniline. Gy JOSEPH REILLY and WILFRED J~OHN HICKINBOTTOM . XV.-Studies of Drying Oils Part I. The Properties of some Cerium Salts obtained from Drying Oils. By ROBERT E~ELBY MORRELL XVI. -The Colouring Matters of Camwood Barwood arid Eianderswood. By PAULINE O'NEILL and ARTI~UR GEORGE . ]HANSAH SMITH DE PENNINGTON . diazoles. 13OWE . CATHERINE CASNIKG HOLMES . IXOBERT WRIGHT 1 3 20 22 28 3 5. 45 57 67 74 79 81 84 99 111 I>ERKIN .. . . 12 iv CONTENTS. XVI1.-Studies on the Walden Inversion. Part VI. The Influence of the Solvent on the Sign of the Product in the Conversion of Phenylbromoacetic Acid to Phenylamino-acetic Acid. By GEORGE SENTER and STANLEY HORWOOD TUCKER . - . XVII1.-Studies on the Walden Inversion. Part VII. The Influence of the Solvent on the Sign of the Product in the Conversion of a-Bromo-P-phenylpropionic Acid to a-Amino-P-phenylpropionic Acid (Phenylalanine). Iminodiphenyl-dipropionic Acid. By GEORGE SENTER HARRY DUGALD KEITH DREW and GERALD HARGRAVE MARTIN . X1X.-The Action of Aniline on Carbon Tetrachloride. By ERNST JOHANNES HARTUNG XX.-The Synthesis of Ammonia at High Temperatures. By EDWARD BRADFORD MAXTED . XX1.-A Reinvestigation of the Cellulose-Dextrose Relation-ship.By MARY CUNNINGHAM . XXI1.-Esparto Cellulose and the Problems of Constitution. By CHARLES FREDERICK CROSS and EDWARD JOHN BEVAN . XXII1.-The Constitution of the Disaccharides. Part 11. Lactose and Melibiose. By WALTER NORMAN HAWORTH and GRACE CUMMING LEITCH . Recent Studies on Active Nitrogen. A Lecture delivered before the Chemical Society on February Zlst 1918. By the HON. ROBERT JOHN STRUTT Part VI. Racemisation Phenomena Observed during the Investigation of the Optically Active Phenyl- and Diphenyl-succinic Acids and their Derivatives. Up HENRY WREN . XXV.-Synthesis of 3 4-Dihydroxyphenanthrene (Morphol) and of 3 4-Phenanthraquinone. By GEORGE BARGER . XXV1.-The Alkaloids'of Ipecacuanha. Part 111.By FRANK LEEPYMAN . XXVI1.-The Supposed Formation of Ergotoxine Ethyl Ester from Ergotinine. A Correction. By GEORGE BARGER and ARTHUR JAMES EWINS . XXVII1.-Interaction of Formaldehyde and Carbamide. By AUGUSTUS EDWARD DIXON . XX1X.-The Sub-bromide and Sub-chloride of Lead. By HENRY GEORGE DENHAM . XXX.-The Structure of Crystalline P-Methylfructoside. By ETTIE STEWART STEELE . XXX1.-Contributions t o the Theory of Solutions. Solubility Studies in Ternary Mixtures of Liquids. By JOHN HOLMES . XX1V.- Studies in the Phenylsnccinic Acid Series, PAGE 14-0 151 163 168 173 182 188 200 210 218 223 235 238 249 257 26 CONTENTS. V ANNCAL GENERAL MEETING . . 276 PACE P&ESIDENTIAL ADDRESS . OBITI~ARY NOTICES . The Old and the New Mineralogy.Hugo Miiller Lecture, delivered before the Chemical Society on April 18th 1918. 13y Sir HENRY ALEXANDER MIERS F.R.S. . XXX 11.-The Synthesis of Ammonia a t High Temperatures. ]?art 11. By EDWARD BRADFORD MAXTED . XX3:III.-Atomic and Molecular Numbers. By HERBERT HTANLEY ALLEN . XXX 1V.-Reactions between Solid Substances. By LESLIE XXXV.-The Association of Organic Compounds in Benzene a.nd Alcohol Solution as Determined by the Tapour Pressure Method. By WILLIAMROSS IBNES . XXX.VI.-The State of Potassium Oleate and of Oleic Acid in Solution in Dry Alcohol Ey MARY EVELYN LAING . XXX.VI1.-Synthesis of Pyranol Derivatives. By SARAT (JHANDRA CHATTERJI and BEOJENDRA NATH GHOSH XXXVII1.-The Abnormality of Strong Electrolytes. Part 1 Electrical Condnctivity of Aqueous Salt Solutions.By JNANENDRA CHANDRA GHOSH . XXX 1X.-" Spinacene and some of its Derivatives." By A. (~HASTON CHAPMAN . . XL.-Metallic Derivations of Alkaloids. By JITENDRA WATH RAKSHIT . XL1.-Studies in Catalysis. Part IX. The Calculation in Absolute Measure of Velocity Constants and Equilibrium Constants in Gaseous Systems. By WILLIAM CUDMORE MCCULLAGH LEWIS . . . IlENRY PARKER . . XLII .-epiBerberine. XLII1.-Water-in-oil Emulsions By ALFRED ULRICH MAX E~CHLAEPFER . XLITr.-The Eelationship bet ween the Optical Rotatory Powers and the Relative Configurations of Optically Active Com-pounds. The Influence of certain Inorganic Haloids on the Optical Rotatory Powers of a-Hydroxy-acids a-Amino-aaids and their Derivatives.By GEORGE WILLIAM CLOUGH XLV.-The Dissociation Constants of some Higher Members of the a-Oximino-fatty Acids. By CEDRIC STANTON HICKS . The ]Principles of Diffusion their Analogies and Applications. A Lecture delivered before the Chemical Society on June 6th, 1918. By HORACE T. BROWN LL.D. F.R.S. . XLV L-Some Piperylhydrazones. By ALBERT WEINHAGEN . By WILLIAM HENRY PEREIN jun. 289 300 363 386 389 396 410 435 444 449 458 466 47 1 492 52 2 526 554 559 58 vi CONTENTS. XLVI1.-Acetyl - p - diazoimides derived from Substituted p-Phenylenediamines. By GILBERT T. MORGAN and DAVID ALEXANDER CLEAGE . XLVII1.-A New Form of Methylgalactosicle and its Conver-sion into Octamethyldigstlactose and into a Methyldigalacto-side.By MARY CUNNINGHAM . XL1X.-The Application of the Auto-condensat ion Powers of y-Sugars to the Synthesis of Carbohydrate Complexes By MARY CUNNINGHAM . I,.-The Preparation of a New Type of Organic Sulphur Com-pound. By GERALD NOEL WHITE . L1.-Double Carbonates of Sodium and Potassium with the Heavy Metals. By MALCOLM PERCIVAL APPLEBEY and KENNETH WESTMACOTT LANE . LI1.-The Constitution of Carbnmides. Part TI. The Mechanism of the Synthesis of Ureit from Urethane. By EMIL ALPHONSE WERNER . LII1.-The Abnormality of Strong Electrolytes. Part 11. The Electrical Conductivity of Non-aqueous Solutions. By JNANENERA CEASDRA GHOSH . . L1V.-A New Synthesis of Tetraphenylpyrrole. Ey GERTRUDE MAUD ROBINSON and ROBERT ROBINSON . . LV.-Nitro-derivatives of Guaiacol.By FANNY POLLECOFF and ROBERT ROBINSON . . LVL-The Propagation of Flame through Tubes of Small Diameter. Ey WILLIAM PAYMAN and RICHARD VERNON WHEELER . LVI1.-The Relative Activities of Methyl Ethyl and n-Pi opyl Iodides with Sodium a- and P-Naphthoxides. By HENRY EDWARDCOX . LVII1.-The Ternary System-Sodium Sulphate Ammonium Sulphate and Water. The Utilisation of Nitre Cake for the Production of Ammonium Sulphate. By HARRY MEDFORD DAWSON . . . L1X.-Acylated p-Phenylenemethyldiamines. By GILBERT T. MORGAN and WILLIAM ROBIXSON GRIST LX.-The Constitution of Carbamides. Part VII. The Mechanism of the Synthesis of Urea from the Interaction of Carbonyl Chloride and Ammonia. Part VIII. The Formation of Urea and of Biuret from Oxamide. By EMIL ALPHONSE WERNER and (Part VIII) GEORGE KINGISFORD CARPENTER .LXL-A New Method for the Determination of Conductivity, By EDGAR NEWBERY . . PAGE 588 59 6 604 60s 609 622 627 639 645 656 666 675 688 694 70 CONTENTS. Vii PAGE LXII:.-The Abnormality of Strong Electrolytes. Part 111. The Osmotic Pressure of Salt Solutions and Equilibrium between Electrolytes. By JNANENDRA CHANDRA GHOSH . LXIl 1.-The Preparation of certain Organic Stanno- and fltanni-chlorides. By JOHN GERALD FREDERICK DRUCE . LXI'T.-The Basic Carbonates of Copper. By HORACE BARRATT IDUNNICLIFF and SUDARSHAN LAL . LXV .-A Study of some Derivatives of Berberine Closely By WILLIAM HENRY Allied to Derivatives of Cryptopine. ]PERKIN jUn. . LXV1.-Morindone. By JOHN LIONEL SIMONSEN .LXVI1.-The Nitration of 2- and 6-Methoxy-m-tolualdehydes rind m-Toluic Acids. By JOHN LIONEL SIMONSEN . LXVII1.-The Bromination of some Derivatives of Veratrole. :By JOHN LIONEL SIMONSEN and MADYAR GOPALA RAU . . LXIX-The Electrical Conductivity of Acids and Bases in Aqueous Solutions. By JNAKENDRA CHANDRA GHOSH . . LXX.-The Freezing Point Curve of Mixtures of Toluene-o- and -p-sulphonamides. Composition of Mixtures of Toluene-o-:md -.-sulphonic Acids. By PHYLLIS VIOLET MCKIE . LXX1.-The Compound H2B,0 and its Salts. By RAMES CHANDRA RAY . LXXI1.-The HSdrates and Alcoholate of Calcium Benzoate. :By FREDERICK STANRRIDGE . . L X S 111.-iV-Acyl Derivatives of Carbazole. By MAURICE COPISAROW LXX.IV.-The Relative Activity of certain Alkyl Iodides with Sodium a-Naphthoxide in Methyl Alcohol.By HENRY :EDWARDCOX . LXX V.-The Hydrolysis of Soap Solutions Measured by the .Rate of Catalysis of Nitrosotriacetonarnine. Ry JAMES .WILLIAM MCBAIN and THOMAS RORERT BOLAM LXX.VI.-Studies in the Phenylsuccinic Acid Series. Part 'VII. The Action of Alcohols and Arnines on r-Diphenyl-succinic Anhydride. By HENRY WREN and HOWELL LXXVI1.-The Inflammation of Mixtures of Methane and Air in a Closed Vessel. LXX VII1.-A eynthesis of isoBrazilein and certain Related Anhydropyranol Salts. Part I. By HERBERT GRACE CRABTREE ROBERT ROBINSON and MAURICE RUSSELL By . 'WILLIAMB . By RICHARD VERNON WHEELER . 'TURNER . LXB:IX.-The Action of Chlorine on the Alkali Iodides. WILLIAM NORMAN RAE , 707 715 718 723 766 775 78 2 790 799 803 808 816 s2 1 825 832 a40 859 88 ...VIIl CONTENTS. LXXX.-Hydroxylamine PIatinum Bases. By LEO ALEXANDRO-LXXX1.-Trimorphic Change of 4-Nitroaceto-o-toluidide. By LXXXII The Preparation of Ethylamine and of Diethyl-LXXXII1.-The Determinaticn of the Molecular CompIexity of LXXX1V.-The Freezing Points of Mixtures of PhenoI, 0-Cresol m-Cresol and p-Cresol. By HARRY MEDFORTH DAWSON and CHRISTOPHER ARCHIBALD MOUNTFORD . . 923 LXXXV.-The Estimation of Phenol and the Three Isomeric Cresols in Mixtures of these Substances. By HARRY MEDFORTH DAWSON and CHRISTOPHER ARCHIBALD MOUNT-LXXXVL-The Oxidation and Ignition of Coal. By RICHARD LXXXV11.-Studies in the Tetrahydronaphthalene Series. By LXXXVIIL-The 9%-Butylarylamines. Part I. The Action of n-Butyl Chloride on 0- and p-Toluidine. By JOSEPH LXXX1X.-The n-Butylarylamines. Part 11. Nitration of By JOSEPH REILLY and PAGE VITSCH T~CHUGAEV and ILJA IWITSCH TBCHERNJBEV . 584 FREDERICK DANIEL CHATTAWAY . . 897 amine. By EMIL ALPHONSE WERNER. . . 899 Liquid Sulphur. By ALEX. MITCHELL KELLAS . . 903 FORD. . . 935 VERNON WHEELER . * . . 945 ARTHUR G. GREEN and FREDERTCK MAURICE ROWE . . 955 REILLY and WILFRED HICKINBOTTOM . . 974 Mono- and Di-n-butyl-p-tohidine. WILFRED HICKINBOTTOM . . 98

ISSN:0368-1645    

DOI:10.1039/CT91813FP001

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

RULE AMIDINE SALTS ETC. 3 I L-Amidine Salts and the Constitution qf the so - ca Ilc d 1932 in oh y d ?,ins. By HAROLD GORDON RULE. THE iminohydrins or isoamides are first meiitioiied by Eschweiler (Bw. 1897 30 1003) who prepared them from thel corresponding imino-ether hydrochlorides by thel action of moist silver oxide or by the interaction of the free imino-ethers and water. The resultr B 4 RULE AMIDINE SALTS AND THE ing compounds from their analysis and apparent unimolecular condition in aqueous solution were represented as having the con-stitution R*C(OH):NH isomeric with the acid amides. Thus the formation of glycolliminohydrin the first of these compounds to be obtained from the corresponding ethyl ether hydrochloride was explained according to the equation OH*CH,*C(OEt):NH,HCl+ AgOH = OH*CH,*C(OH):NH + AgCl+ EtOH, the iminohydrin together with a large proportion of glycollamide, being supposed to result from the direct hydrolytic action of the water present.I n addition to the above lactiminohydrin and a-hydroxyisobutyriminohydrin were prepared and very shortly described. The chief characteristics of these compounds as noted by Esch-weiler are their high melting points fusion being generally accom-panied by decomposition the liberation of ammonia by alkalis, and their peculiar reaction towards certain metiallic salts the glycollic compound for example slowly giving a deposit of calcium glycollate on the addition of a solution of calcium chloride. The latter action was supposed t o take the course 20H-CH2*C(OR):NH + CaC1 + 2H20 = (OH*CH,*CO,)Ca + 2NH,Cl.Eschweiler further states that the irriiiiohydrins are basic i 11 character and cldims t o have isolated definite hydrochlorides of the general type R*C(OH):NH,HCl which are neutral in aqueous solution. The failure of all attempts to effect' an interconversion between the iminohydrins and their apparent isomerides the acid amides, led to an extended investigation by Hantzsch (Ber. 1901 34, 3142) who showed that these compounds were. comparatively strong electrolytes having in reality a molecular weight double that assigned to them by Eschweiler. In opposition to the latter author Hantzsch finds the iminohydrin hydrochloride to be strongly hydrolysed in aqueous solution and also comments 011 the fact that all the known iminohydrins are derivatives of a-hydroxy-acids." I n spite of numerous attlempte however he was unable to prepare other types.I n explanation OF the dis-covery that the iminohydrins were electrolytes of the general formula (R*CO*NH,), they were represented as having the con-stitutJon NH:CR*O*NH,:CR*OH the complex being supposed to ionise in aqueous solution into the ions (NH:CR*O)' and * In a patent application Eschweiler makes the bare claim to have prepared wet- and bone-iminohydrins but no further details are given CONSTITUTION OF THE SO-CALLED IMINOHYDRINS. 5 (NH,:CR-OH)’. The failure to establish any relationship to the acid amides despite the similarity between the structure of these compounds and thatt suggested above for the iminohydrins was met by Hantzsch with the statement that “amides and isoamides (iminohydrins) are not isomerides but polymerides and their relations are theref ore different from those of genuine tautomerides, which possem equal molecular weights.” The hydrochloride of glycolliminohydrin was nevertheless formulated as OR*CH,*C(OH):NH,Cl, in which case we should have a true isomeride of glycollamide exist-ing in combination with hydrochloric acid.More recently the behaviour in solution of glycolliminohydrin, lactiminohydrin and their salta has been examined by Professor James Walker (see Note to preceding paper) with results which led him to the conclusion that these compounds are not true amphot’eric electrolytes and that the formula assigned to them by Hantzsch is incorrect.For this reason and since all previous at’tempts to prepare imiiiohydrins other than a-hydroxy-deriv-atives had failed pointing to the possibility that tho hydroxyl group was an integral part of the molecule the following investiga-tion was undertaken. Several representatives of this class have been prepare’d and examined and all were found to possess the high molecular weight and saline properties characteristic of glycolliminohydrin. The early preparation of the methoxyacetic and the phenylacetic deriv-atives showed that< the formation of an iminohydrin was in no way dependent on the presence of an cchydroxy-group in the molecule of the interacting imino-ether. Subsequently an ex-amination of the comparatively stable mandelic compound * led to the discovery that the iminohydrins are complex amidine salts of the general formula R*C(NH,):N€I,R*CO,H.Th;s was con-firmed by the synthesis of mandeliminohyclrin (mandelamidine mandelate) from m andelamidine hydrochloride and sodium mandelate, C6H5*CH(OH)*C(NH,):NH,HC1 + C,H,*CH(OH)*CO,Na = C6H5*CH( OH)-C( NH,) :NH ,C,H,*CH( OH) *CO,H + NaCl, and of Eschweiler’s original glycolliminohydrin (glycollami dine glycollate) from the corresponding amidine hydrochloride and sodium glycollate, OH*CH,*C(NH,):NR,HCl+ OH*CH,*CO,Na = I n connexion with the latter synthesis for which glycollamidine OH*CH,*C(NH,):NH,OH~CH,*CO,H + NaCl. * Seeipreceding paper by J. E. Mackenzie 6 RULE AMIDINE SALTS AND THE hydrochloride had first t o be prepared some of Eschweiler's work on the iminohydrin (amidine) salts has been repeated and several inaccuracies have been corrected.From the above point! of view a review of the properties of the " iminohydrins " presents no peculiarities. Evidence of saline character is furnished by high melting points insolubilit-y in ether or hydrocarbons and by high electrical conductivities in aqueous solution the latter in the case of the glycollic compound being very little short of the value for a typical salt such as sodium acetate. The reaction with metallic salts is seen to be an example of ordinary double decomposition that between glycolliminohydrin and calcium chloride following the course 20H*CH2*C(NH,):NH,0H*CH,*C0,H + CaC1 = 20H*CH,*C'(NH2):NH,HC1 + (OH*CH2~C"0,),Ca. The soluble substance left' in solution is glycollamidine hydro-chloride and not ammonium chloride as assumed by Eschweiler, and later by Hantzsch.Characteristic of amidine salts is the disruption which accompanies fusion and the readiness with which ammonia is evolved on treatment with alkalis whilst the decorn-position suffered by the iininohydrins in general on heating with aqueous solvents is due t o hydrolysis of the amidine into amide and ammonia,. This is well illust'rated in thel case of the phenyl-acetic compound where attempted crystallisation from alcohol was fouiid to lead to the production of phenylacetamide and ammonium phenylacetate, CH,Ph*C(NHz):NH,@HzPh*CO,H + H,O = The contradictory statements of Eschweiler and Wantzsch in connexion with the neutrality of the " iminohydrin salts " are also made clear since these authors believed that the iminohydrin, (R-C(OH):NH), was capable of uniting with two molecules of hydrochloric acid to yield two molecules of the salt, R-C(OH):NH,HCl.The hydrochloride in reality an amidine salt as isolated by Escli-weiler proved to be neutral when dissolved in water whilst hydro-lysis measure'ments carried out by Hantzsch with a solution con-taining one molecular proportion of iminohydrin t o two of hydro-chloric acid naturally led to the conclusion khat the salt was considerably hydrolysed. The organic acid which is liberated in the latter case remains practically non-ionised in the presence of the excess of hydrochloric acid thus accounting for the apparent dissociation values of 50 per cent.obtained by Walker (see Note to preceding paper) for glycolliminohydrin and lactiminohydrin CH,Ph-CO*NH -+ CH2Ph*C0,NH, CONSTITUTTON O F 'I'LIE SO CRTdLEl) 1 MIINOI1YI)RINS. 7 ltyclrochloridea and by the author for the iiietlioxyacetic aiicl iiiandelic derivatives. Mechnrzisnz of t h e Interaction of Iinino-etlhers mid Tl'cctrr. Pinner in his monograph on the imino-ethers (" Die Imidoather und ihre Derivate ") states that these compounds decompose slowly on keeping generally giving rise to the alcohol and nitrile from which they are derived. I n some cases the nitrile may poly-merise on being liberated whilst in others the decompositiofi may take place in a different manner and lead to the formation of an acid amide. An example of the' latter type is furnished by a-hydroxyisobutyrimino-ethyl ether (Pinner Zoc.cit . p. 37) which on attempted distillation decomposes into the corresponding amide and alcohol and i t is probable that the interaction between benz-irnino-ethyl ether and water to form cyaphenin (Mackenzie P., 1913 29 175) is due to the initial formation and subsequent poly-merisation of benzonitrile. I n those reactions where water is present however other changes may take place. Imino-ethers are at once strongly alkaline' and readily hydrolysable compounds and the work of Pinner has shown that the imino- and alkyloxy-groupings are extremely sensitive t o attack the actual group or groups affected depending on the reagent employed. I n particular ammonia reacts with imino-ether hydrochlorides with great readiness to form amidine salts.Although in no single instance was any trace of free ammonia observed during the above interact'ions between imino-ether and water it was found by experiment thatl the addition of a 11 equivalent of ainmonium mandelate to an aqueous suspension of mandelimino-ethyl ether not only doubled the yield of amidine mandelate but the deposition of the salt commenced almost immediately after the addition had been made. It seems prob-able then that in the interaction of imino-ethers and water the first step is autohydrolysis of a portion of the subst'aiice in the alkaline medium to form the ammonium salt of the corresponding acid, R*C(OEt):NH + 2H20 = R*C(ONH4):0 + EtOH. This salt then reacts with more free imino-ether to give the amidine salt or iminohydrin, R*C(ONH,):O + R.C(OEt'):NH =z R*C(NFI,):NH,R*CO,H + EtOH.l t i this connexiou Pinner in describing the formation of amidine hydrochloride from imino-ether hydrochloride and a slight excess of alcoholic ammonia remarks on the precipitation o S RULE AMIDINE SALTS AND THE ammonium chloride which then slowly dissolves with the formation of the soluble amidine salt.* The production of amide is probably caused by direct hydro-lysis of imino-ether and amidine in the alkaline solution and the amount4 formed in any given experiment does not appear to bear any constant relation to that of the amidine salt!. E X P E R I M E N T A L . The method of preparation adopted by Eschweiler and later by Hantzsch in which the imino-et,her hydrochloride is added in small portions at a time to an equivalent amount of silver oxide suspended in water led to such small and variable yields that its use was abandoned.Yields of 30-35 per cent. were obtained by allowing the free imino-ethers to remain with excess of water for some days a t the ordinary temperature. During this time the originally strong a1 kaline reaction of the iniii?cwt8her gradually disappeared and a mixture of irninohydrin anti acid was produced. Atl firsfi the imiaohydrin was isolated by repeated crystallisation from a suitable solvent. I n some later cases the dried products of reaction were extracted with ether in a Soxhlet apparatus the iiisoluble iiniiiohydrin being left behind in a comparatively pure state.‘ Glycolliminohydrin ” (glycol1 amidiiie glycollate) was prepared in a 30 per cent. yield by dissolving glycollimino-ethyl ether in excess of water and allowing the solution to remain for ten or twelve days. On evaporation to dryness in a vacuum over sulphuric acid and repeated recrystallisation of the residual solid from alcohol the pure iminohydrin was obtained in well-defined plates melting and decomposing a t 166-1 6 8 O . Eschweiler (Zoc. c i t . ) gives 161-162O. I n the hope of isolating some definite oxidation or reduction product an electrolysis of the iminohydrin in aqueous solution was carried out in a divided cell. An analysis of the electrode gases, however indicated complete disruption of the iminohydrin mole-cule. Similarly all attempts by chemical means to isolate a basic or acidic component other than ammonia or glycollic acid both of which were believed to be products of hydrolysis led to no result.Earlier attempts t o prepare acet- and benz-iminohydrins were also unsuccessful (compare Hantzsch loc. cit. and Mackenzie P., 1913 29 175) the only recognisable products of reaction in the * Since the above WBP wribten a paper has been published by A . Knorr (Ber. 1917 50 229) in which the aut’hor claims to have shown conc1usivc;ly Ohat free ammonia does not react with free imino-ethers but that amidine hydrochlorides are formed from ellern by reaction with ammonium chloride CONSTITUTION OF THE SO-CALLED IMINOHYDRINS. 9 case of benzimino-ethyl ether being benzamide cyaphenin and a little ethyl benzoate.The first indicatdon that the presence of an a-hydroxy-group was not an essential condition for the formation of an iminohydrin was given by the preparation of methoxyaceb iminohydrin . ~ethoxyacetimino-eth.yl Ether CH,-O*CH,*C(O-C,H,):NH. Methoxyacetonitrile (29 grams) prepared from paraformaldehyde according to Wedekind’s method (Ber. 1903 36 1383) was dis-solved in ether and treated with an equivalent (24 c.c.) of absolute alcohol. The solution was cooled in ice and dry hydrogen chloride (15 grams) passed in. After a short time the liquid separated into two layers and subsequently methoxyacetimino-ethyl ether hydrochloride crystallised out. Some of the hydrochloride (16 grams) was shaken with ether and a concentrated solution of potassium carbonate.Much carboil dioxide was evolved and the ethereal extract after drying over sodium sulphate was distilled. The boiling point of the distillate slowly rose to 136O where i t remained constant. The yield of methoxyacetimino-ethyl ether (b. p. 136O) was 5-5 grams. The imino-ether is a colourless liquid with a peculiar odour; it is alkaline to litmus and miscible in all proportions with water. Ammonia is readily evolved on treatment with alkalis. 0.1789 gave 0.3381 CO and 0.1474 H,O. It is probable that the substance was not. quite pure since all imino-ethers decompose to some extent on heating. An attempt to purify a portion by distillation under 50 mm. pressure gave a distillate passing over a t 66-67O. This specimen on analysis proved to be no purer than the above.Met hoxyacetiminohydrin ” ( m e t hoxyacet antidime met hox y-acetate) was obtained by allowing the free imino-ether (12 grams), mixed with excess of water to remain at the ordinary tempera-ture for five weeks. The water was removed in a vacuum over sulphuric acid and the resulting mixture recrystallised repeatedly from alcohol containing about a third of its volume of benzene. The iminohydrin (2.2 grams) was obtlained in large well-shaped needles melting a t 162-164O : C=51*52; H=9*22. C5H,,O2N requires C= 51-25 ; H = 9-47 per cent. 0.1835 gave 0.2715 CO and 0.1332 H,O. It is readily soluble in alcohol and moderately so in water. C=40*35; H=8.06. C6H1404N2 requires C = 40.42 ; H = 7.93 per cent. In On heating with aqueous ether or benzene it dissolves sparingly.sodium hydroxide ammonia is evolved. B 10 RULE AMIDINE SALTS AND THE M o l e c i d i l r IVeiyh~ i i i A pcc)?[.s rS’ol(1ctiott (Cryoscopic N c t A od). Using 20 grams of solvent the following data were obtained 0.1225 gave At= - 0.129O. (K= 1870) : M.W. = 89. 0.2481 , At= - 0.250’. M.W. -= 93. 0.3067 ,) At= - 0.309’. M.W. = 93. C,,FI,,0,N2 requires M.W. = 178 hence at the above dilutiolls the substance is almost completely ionised Electr.ical Cotaductivity in IT’ater nt 25’. The following determinations were made using electrodes covered with a deposit ol “grey” platinum and t o reduce still further errors arising from the oxidation at the electrodes the electrolyte a t each dilution was freshly prepared from a stock solution bj7 the addition of the requisite amount of water (pZ5 = 1.6 x 10-6).An N/20-solulion was prepared by dissolving 0.8907 gram of the ‘‘ iminohydrin ” up to 100 C.C. ...... 20 40 100 200 400 1000 2000 ,u~~....,. 60.9 64.0 67.S 69.8 50.8 71.8 72 0 At dilution v=2000 oxidation was noticeable as shown by the dropping of the cell-resistance. The figures show methoxyacet-iminohydrin to be a good electrolyte with a conductivity at high dilutions comparable with that of glycollirninohydrin for which Hantzsch finds ~ ~ ~ = 7 9 . 5 at ~ ~ 2 0 4 8 . Hydrolysis of &€ e t hotyxyn ce t i )ti ino hydrin Hydrocli loride.” According to Eschweiler and Hantzsch the iminohydrins form hydrochlorides of the general type R*C(OH):NH,HCl salts which are considerably hydrolysed in aqueous solution.Walker (see Note) to preceding paper) finds this hydrolysis in the case of the glycollic and lactic derivatives t o approximate t o 50 per cent. in A’ / 8 -so 1 u t i on. The hydrolysis a t the same dilutdon of methoxyacetimiriohydrin hydrochloride was measured by the methyl acetate catalysis method, and found in this case also to be almost exactly 50 pcr cent, Experiments directed towards the preparation of the unsubsti-tuted “ iminohydriiis ” corresponding with benzoic phenylacetic, and acetic acids met a t first with no success. As has been already stated beiizimino-ethyl ether reacts with water to give cyaphenin, and failure in the cases of phenylacet- and acet-imino-ethyl ethers was subsequently found t20 be due t o hydrolysis of the “imino CONSTITUTION OF TIIE SO-CALLED IMINOHYDRINS.1 1 hyclrins ” during attempted purification by crystallisation. The two latter compounds were eveukually obtained from the crude reaction mixture after removing the accompanying acid amid0 by extraction with ether in a Soxhlet apparatus. “ L4 cetinainohydrin ” ( A cetnnaidine A cettrtc), CH,*C(NH,) :NH,CH,*CO,H. Acetimino-ethyl ether hydrochloride prepared from acetonitrile (37.5 grams) alcohol and hydrogen chloride in the usual manner, was converted into the free imino-ether by shaking with ether and a concentrated solution of potassium carbonate. The bulk of the ether was cautiously removed on the water-bath and thel residual liquid mixed with excess of water in a stoppered bottle. After ten weeks the still faintly alkaline solution was evaporated to dryness in a vacuum over sulphuric acid and the solid residue extracted with ether in a Soxhlet apparatus.The residue melt-ing a t 66-148* was partly soluble in benzene the solution deposit-ing crystals of acetamide (m. p. 79-82O). The insoluble portion, amounting to 3 grams melted a t 155-175O. The latter was purified by solution in cold alcohol and precipitation with benzene, giving a final product melting and decomposing atl 185-187’. All attempts to recrystallise i t from warm alcohol or ethyl acetate with or without the addition of benzene resulted in the de corn p osition of the iminoh y dr in. Qualitative tests showed that this substance was a good electro-lyte whilst its high melting point insolubility in ether and the evolution of ammonia with sodium hydroxide showed it to be of the same class of substances as glycolliminohydrin.Owing to the low yield and its unstable nature it was not further examined. ( ( Ph enyla cet imitr oh ydrin ” (Phen ylnce t a midi? e Phen ylacet rr t e), C‘,H,*CH,*C(NH,) :NII,CY6H5*CI12.C0,H. Free phenylacetimino-ethyl ether prepared from phenylaoeto-nitrile’ (Pinner ‘‘ Die1 Imidoather,” p. 66) was allowed t o remain in contact with water at the ordinary temperature for several weeks. The semi-solid mass was filtered and the solid portion, after drying extracted with ether in a Soxhlet apparatus. After thirty hours’ extraction the iminohydrin was left b e h i d in a pure state melting and decomposing a t 227-230° : 0.1586 gave 0.4138 (20 and 0.0974 H,O.C,,H,,O,N requires C = 71.10 ; I3 = 6-72 per cent. By solution in ethyl acetate and precipitation with benzene a product of the original melting point was obtained in very fin0 C=71 13; H=6*82, B” 12 RULE AMIDINE SALTS AND THE needles. The substance is very sparingly soluble in water soluble in alcohol and insoluble in benzene or ether. With aqueous alkalis ammonia is readily evolved and the compound is of the same unstable nature as acetiminohydrin attempted recrystallisa-tion from alcohol or water leading to partial decomposition into amide and the ammonium salt of the corresponding acid. For this reason it was not further examined. The four ‘( iminohydrins ” described above derivatives of glycollic, methoxyacetic acetic and phenylacetic acids were not suited t o a detailed investigation on account of their instability towards solvents and their general physical properties.A more convenient subject for examination was found in ‘‘ mandeliminohydrin.” ( ( ~a?2deli?~ii.l~ol~~~~~~}~ ’’ (Jfa?idelarnidiiz e iiandellrt e) , C,H,*CH (OH)* C(NH,) :NH,C,H,-CB(OH)* C0,H. This compound had already been obtained in small quantities by Mackenzie (see precediiig paper) by the interaction of aqueous silver oxide and mandelimino-ethyl ether hydrochloride. I n the preparation of larger quantities it was obtained from benzaldehyde as follows. Moist potassium cyanide (80 grams) was placed in a flask and covered with an ethereal solution of one equivalent (106 grams) of benzaldehyde.The whole was cooled in ice and rather less than one equivalent (50 c.c.) of concentrated hydrochloric acid added slowly with constant shaking. The ethereal solution was decanted and dried for twenty-four hours over anhydrous sodium sulphate, after which it was poured off and cooled in ice. Equivalent amounts of alcohol (46 grams) and dry hydrogen chloride (36.5 gramsj were added and after a shortl time the liquid became almost solid owing to the separation of mandelimino-ethyl ether hydrochloride. I n a few hours the latter (135 grams) was collected. The hydrochloride was suspended in ether and shaken with a conoentrated solution of potassium carbonate. On removal of the ethereal layer and evaporation of the solvent in a vacuum the free imino-ether (87 grams) remained as a white solid.The imino-ether was introduced into a stoppered bottde contain-ing excess of water and the latter placed in a shaking machine. After five or six days the bulk of the solid suddenly passed into solution when the reaction mixture was removed and the water evaporated in a vacuum over sulphuric acid. The dry residue was transferred to a Soxhlet apparatus and extracted for some hours with ether leaving an insoluble portion melting and decom-posing at about 180° which after one crystallisation from alcohol CONSTITUTION OF THE SO-CALLED IMINOHYDRINS. 13 gave the pure iminohydrin (25 grams) melting and decomposing a t 185-187O. Mackenzie quotes 173-179O (see preceding paper), the actual figure depending very much on the rate of heating.Mandelamidine mandelat e crystallises in colourless plates in-soluble in ether benzene or light petroleum sparingly soluble in water (100 grams dissolve 1.87 grains atl 25O) rather more readily so in ethyl alcohol and moderately so in methyl alcohol (100 grams dissolve 4.80 grams a t 25O). It’ is comparatively unaffected by solvents and can be recovered from them unchanged whereas glycolliminohydrin recovered for example from a solution in hot alcohol has always a decidedly lower melting point than the start-ing material. ilfolec.ztlw 1 Veigh t itL A q t6 eo us Solu t i o i ~ (G’r~oscoyic Met k od). Using 20 grams of solvent the following data were obtained 0*1210 gave A t = -0.073. M.W.=155. C,,H,,O,N requires M.W. = 302 hence a t these dilutions the compound is almostl completely ionised.I n boiling methyl alcohol (pure anhydrous) the following figures were obtained using an electrically heated modification of Beck-mann’s apparatus jacketed in a vacuum tube. (K = 1870) : 0.2348 , A t = -0.147. M.W.=149. Weight of alcohol taken 27.91 grams (K=860). 0.5340 gave E = 0.080. M. W. = 206. 0.9923 , , =0.150. M.W.=204. 1.384 , , ~0.214. M.W.=200. As was to be expected these figures indicate partial ionisation only of the compound in methyl alcohol. Electrical Conducthit?/ in ?Vater a t 2 5 O . As in the case of methoxyacetirninohydrin the electrodes used were coated with “grey .’ platinum but at8 the higher dilutions, 1 1 - 400 and above oxidation was made apparent’ by the falling resistance of tlhe cell.The solution a t each dilution was freshly made u p from an N/20-stoclr solutdon containing 1.511 grams in 100 C.C. The water used had a specific conductivity value of 1.4 x 10-6 a t 25O. v ...... 20 40 100 200 400 1000 2000 p,,...... 43.0 46.0 51.0 53.0 54.4 55.2 56. 14 RULE AMI1)INE SALTS AND THE (‘ Ma ?rdelinziiaohydi.irt El ydrochloride. ” The hydrolysis in aqueous solution of the (‘hydrochloride of glycollimiiiohydrin ” was measured by Hantzsch by determining the electrical conductivity of a solution containing one molecular proportion of the bimolecular “ iminohydrin ” and two molecular proportions of hydrogen chloride. The figures obtsined indicated extensive hydrolysis. As already stated Walker using the methyl acetate catalysis method found almost exactly 50 per cent.of the hydrogen chloride in the uncombined state in N/8-solution. The hydrolysis of the mandelic compound determined by the latter method was again found to be 50 per cent. in N/1&solution. On the other hand Eschweiler states (compare Hantzsch Ber. 1901, 34 3154) that glycolliminohydrin hydfochloride obtained by evaporation of the solution of iininohydrin in hydrochIoric acid, is a neutral salt having the structure OH-CH,*@(OH):NH,HCl. (‘ Mandeliminohydrin,” on being treated with excesq of aqueous hydrochloric acid and evaporation in a vacuum over solid potassium hydroxide was found t o retain exactly a half-equivalent of acid, which could be estimated by titration with standard alkali in the presence of methyl-red. This solid hydrochloride showed no definite melting point but ‘I mandeliminohydrin,” when dissolved in hot dilute hydrochloric acid deposited on cooling well-f orined crystals of a hydrochloride nielting at 215-219O.These crystals proved to be1 neutral in aqueous solution and evolved much ammonia with sodium hydroxide. *4 ction of Alkalis on ( ( ~mndeliiziitioltydi.irL.“ I n the course of some experiments on the action of alkalis on mandeliminohydrin,” an aqueous solution of the latter was treated with exactly one molecular equivalent of sodium hydr-oxide. No ammonia could be detected after remaining for some minutes in the cold but on warming the strongly alkaline solution, a considerable evolution of the gas was observed. The mixture was boiled until the evolution of ammonia ceased when the resi-dual liquid was found to be neutral.On cooling a crop of crystals was deposited melting at 128-132*. These after crystal-lisation from alcohol melted a t 131-13Z0 and proved to be pure mandelamide. The aqueous mother liquor contained sodium inandelate and yielded free mandeIic acid on acidification. No other product could be detected. These results suggested that the basic portion of the irnino-hydrin was set free by alkali and subsequently decomposed wit CONSTITUTION OF THE SO-CALLED 1MINOHIYI)RINS. 15 evolution of amrnonia. Attempts to isolate a base soluble in ether were only successful when the aqueous alkali originally in use was replaced by a saturated solution. When the finely powdered iminohydrin was rapidly shaken in a separating funnel with ether and saturated aqueous potassium hydroxide the ethereal layer left on evaporation in a vacuum a very small amount of a white solid.This substance melted at 98-110° was soluble in water giving a powerfully alkaline solu-tion and after a short time decomposed with the evolution of much ammonia. These properties are those of an amidine mandel-amidine C,H,*CH(OH)*C(NH,):NH (Beyer J . pr. Chem. 1885, [ii] 31 383) melting a t llOo. The neutral hydrochloride melt-ing a t 215-219O obt’ained above should then correspond with mandelamidine hydrochloride C,H,*CH( OH)*C( NH,) :NH,HC1, which melts a t 213-214O (Beyer). A specimen of the latter pre-lmreci from mande81imiiio-ethy1 ether hydrochloride a i d alcoholic ammonia was found t o melt at 219-220O.The behaviour of “ mandeliminohydrin ” towards acids and alkalis coupled with the characteristic reaction of glycollimino-hydrin with calcium chloride resulting in the deposition of calcium glycollate pointed t o these compounds being in reality amidine salts of the general type R*C(NH,):NH,R*CO,H. Synthesis of (‘ Mandel.lnzi?2ohycin.~’ This constitution was readily confirmed by the formation of the iminohydrin ” on mixing in warm aqueous solution equivalent amounts of mandelaniidine hydrochloride and sodium mandelate. On cooling the solution deposited hard nodules melting and decomposing a t 1 75-180° which after recrystallisation from alcohol showed the characteristic plate formation of “ mandel-iminohydrin,” and melted and decomposed a t 184-186O.Synthesis of “ Glycollimi~zohydrit~ .,’ Equivalent amounts of sodium glycollato and glycollamidine hydrochloride (for preparation see later) were mixed in aqueous solution. After evaporating t o dryness ext’raction with alcohol removed “ glycolliminohydrin,” melting at 166-168O. “ p-Ch1oromandeliminohiyd.ri.n ” ( pChloronzandelamidirte p-Chloro-nr a d e l a t e ) C,H,Cl-@H (OH)*C( NH,) :NH C,H,Cl-CH( OH)=CO,H. This compound was prepared for the purpose of comparing its physical constants with those of the mandelic derivative before th I6 RULE AMIDINE SALTS AND THE constitution of the iminohydrins as amidine salts had been estab -lished. The preparation was a somewhat lengthy process start-ing with the conversion of pchlorotoluene into Pchlorobenzyl-idem chloride C,H4C1*CHC1, by the action of chlorine on the boiling liquid under the influence of rays from a (( Uviol " mercury-vapour lamp.The chloro-compound was heated in a sealed tube a t 170° with water yielding p-chlorobenzaldehyde and the latter extracted with ether. The ethereal solution after drying over sodium sulphate was used direct for the preparation of p-chloro-mandelimino-et hyE ether C,H4C1=CH (OH) C( OEt) XH by the method used above for the mandelic compound. Owing to the great tendency of the chloroaldehyde to oxidise in air it was found necessary t o carry out the reaction in closed vewds in an atmo-sphere of carbon dioxide. idene chloride gave 8 grams of the free imino-ether. 'The compound crystallised from ether in well-defined plates melt-ing a t 107-logo.When recrystallised from light petroleum i t melted a t 108-110°. The crude product tends t o oxidise in air becoming red but the pure substance can be kept for some weeks without much dis-coloration. It is sparingly soluble in water soluble in dilute hydrochloric acid o r alcohol and readily so in hot benzene from which it is precipitated by light petroleum. An attempt to determine the chlorine content by Stepanov's method using alcohol and metallic sodium led t o too high a figure being found and i t was noticed that decomposition of the imino-ether had taken place in such a way as to lead t o the production of hydrogen cyanide. Using the Carius-Volhard method the following figures were obtained 0.1172 gram was heated in a sealed tube with 0.2242 gram of silver nitrate and 2 C.C.of fuming nitric acid. After the reaction the oxides of nitrogen were removed and the unchanged silver nitrate was titrated with thiocyanats of which 7.35 C.C. (0*1052N) were required : Twenty-f our grams of p-chlorobenzyl Cl= 16.5. C,,H,,O,NCl requires (21 = 16.6 per cent. '' Chloromandeliminohydrin " was prepared in small quantity only by the method adopted in the case of the mandelic derivative. Continuous extraction of the dry product with ether separated the mixt'ure into two portions CONSTITUTION OF TRE SO-CALLED IMINOHYDRINS. 17 p-Ghloroman d elamide C,H,Cl*CH (OH) *CO*NH,. The ethereal extract deposited a white crystalline substance which on crystallisation from benzene melted a t 122-123O. Analysis showed this to be the expected pchloromandelamide.On hydrolysis with alkali it yielded ammonia and a salt of chloro-mandelic acid. 0.1162 Gram heated with 0.2626 gram of silvsr nitrate and fuming nitric acid required for titration 9.10 C.C. of N/lO-thio-cyanate. C1= 19.4. C8H,0,NC1 requires C1= 19.1 per cent!. The amide is soluble in alcohol sparingly so in ether and very sparingly so in benzene. p-Chloromandelamidine p-chloro-mnndelate was left behind in the crude state after extraction with ether as a white powder melting a t 170-180°. Recrystallisation from a mixture of alcohol and benzene raised the melting point to 186-195O (with decomposition). This compound proved to be unexpectedly unstable and very readily decomposed with the evolution of ammonia on heating with solvents.Owing t o its instability and the fact that its percentage composition does n o t differ from that of the amide with which it i,s liable to be contaminated it was not further examined. Treatment with dilute hydrochloric acid and subsequent recrystal-lisation from alcohol yielded the crystalline p-chloromandelamidine hydrochloride C,H,Cl-CH (OH)-C { NH,) NH H C1 melting and decomposing a t 252-253O : 0.3360 required 15-20 C.C. Nl10-AgNO,. C1’ = 16-04 C,H,ON,Cl,HCl requires C1’ = 15*97 per cent. Amidiize Salts. Some compounds of this type have been described by Eschweiler under the heading of “iminohydrin salts,” but since much of t,he data furnished by this author is inaccurate and since moreover, he was under a misapprehension as to the structure of the com-pounds with which he was dealing it was thought desirable to repeat certain of the preparations.Glycollamidine Hydrochloride OH*CH,=C(NH,):NH,HCl. Eschweiler (ibid.) describes glycolliminohydrin hydrochloride as being prepared by the evaporation of a solutlion of the iminohydrin in an equivalent’ amount of dilute hydrochloric acid. The re 18 RULE AMIlXNE SALTS AND THE crystallised product is quoted as melting a t 135O and bavirlg the structure OH* CH,-C (OH) :NH ,HC1. Glycollamidine glycollate prepared froin the free imino-ether by treatment with water gave on evaporation with hydrochloric acid a crude product melting a t 130-150". After repeated purification by solution in hot alcohol and precipitation with benzene the hydrochloride was obtained in very fine needles melt-ing att 150-151°.I n larger quantities t,his salt was prepared from glycolliniiao-ehhyl ether hydrochloride and alcoholic ammonia according to the general method recommended by Pinner ( l o c . cit.). After puri-fication from 98 per cent alcohol. a product of the above melting point was obtained. 0.2003 was distilled with excess of sodium hydroxide and the ammonia trapped in 25 C.C. of (1.2036 iT-sulphuric acid. The excess of acid required 7-70 c.c. of 0.1934 #-sodium hydroxide. N = 25.17. 0.1037 treated with 20 C.C. of NIlO-silver nitrate required for titration 10.65 C.C. of N/lO-ammonium thiocyanate. C1= 31.97. C,H,ON,,HCl requires N = 25.34 ; C1= 32.08 per cent. The salt is sparingly soluble in alcohol and practically insoluble It is very readily soluble in water and in benzene or ether.deliquescent in air. Glycollamidine Sulph>ate (OH.CB,*C(NH,):NH),,H,SO,. Glycollamidine hydrochloride was treated with an equivalent of sulphuric acid and the excess of water evaporated on the steam-bath. Recrystallisation from aqueous alcohol gave the sulphate in colourless leaflets melting and decomposing a t 205O. Eschweiler (Zoc. c i t . ) gives 150° as the melting pointl of glycolliminohydrin sulphat'e prepared in a similar manner : S= 12.78. 0.2042 gave 0.1900 BaSO,. The salt is nob deliquescent is readily soluble in water and very (C,H,ON,),H,SO requires S = 13.02 per cent. sparingly so in absolute alcohol. (n'lycoltamicfiine Hyd?*oge?t Sulp?~/rfc7 OH.CH,*C(NH2):NH,H,S0,.I n order to ascertain if Eschweiler's sulphate melting a t 150°, were the hydrogen sulphate glycollamidine hydrochloride was treated in aqueous solution wit'h exactly two equivalents of sulphuric acid and evaporated to dryness in a vacuum over sodium hydr-oxide and sulphuric acid. The product was quite free fro chloride and after drying on porous porcelain in a vacuum melted at 65-67O after having softened at 63O. On recrystallisation from aqueous alcohol leaflets melting at’ 150-1‘75° were deposit’ed, which proved on analysis to contain more than 90 per cent. of the normal sulphate. Even from solvents containing a large excess of acid the crystals deposited were mainly of the normal salt. G 7y c oUc/ nz idin e Nitro t e OH- C H,* C (N H3) N H H NO,.This substance was obtained by evaporating on the steam-bath equivalent amounts of glycollamidine hydrochloride and aqueous ilitric acid. Recryst’allisation from aqueous alcohol gave the pure nitrate melting a t 110-11lo (Eschweiler gives 9 5 O as the melting point of glycolliminohydrin nitrate). A product melting a t l l O - l l l o was also obtained from glycoll-aniidine glycollate (iminohydrin) and nitric acid : 0.2330 gave 0.1504 GO and 0.1074 H,O. 0.1497 ) 39-10 C.C. N (dry) at 10-5O and 747 mm. N=30.88. C=17*58; H=5.15. C,H,ON,,HNO requires C= 17.52 ; H= 5-15 ; N =30*68 per cent. The salt is very readily soluble in water and practically in-soluble in absolute alcohol benzene or ether. From aqueous alcohol it is deposited in leaflets which are stable in air.Eschweiler’s ‘‘ lactiminohydrin sulphate ” (lactamidine sulphate) is correctly quoted as melting at about 1 9 8 O . A specimen pre-pared from the “iminohydrin” was found to melt and decompose at 2OO-20Zo. The hydrochloride and nitrate have already been described by Pinner. Sum rri a r y . (1) The iminohydrins or isoamides formulated by Eschweiler as R*C(OH):NH and by Hantzsch as NH:CR*O*NH,:CR*OH have been,shown to be amidine salts of the general type R*C(NH,):NH,R-CO,H. This structure has been confirmed by the synthesis of the maiidelic compound and of Eschweiler’s original “ glycolliminohydrin.” (2) It is suggested that the production of amidine salt by tlie reaction between imino-ether and water takes place mainly through the intermediate format.ion of the ammonium salt of the corre-sponding acid which by subsequent reaction with free imino-ether gives rise to the amidine salt. (3) Certain inaccuracies of Eschweiler in reference to “imino-hydrin ’’ (amidine) salts have been corrected 20 WERNER THE PREPARATION OF a-NAPHTHOLPHTHALEIN. I n conclusion I desire t o express my thanks to Professor Walker, a t whose suggestion the above work was undertaken for the interest he has shown throughout its course. 1 am also indebted to the Earl of Moray Research E’und for a grant which has covered most of the expenses in connexion with this research, CHEMISTRY DEPARTMENT, UNIVERSITY OF EDINBTJICGH. [Received J u l y 2nd 1917.

ISSN:0368-1645    

DOI:10.1039/CT9181300003

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

20 WERNER THE PREPARATION OF a-NAPHTHOLPHTHALEIN. I I I. - The Prep am t io ti of a- Nap h t h o lp h t h a1 e in. By EMIL ALPHONSE WERNER. BY heating phthalic anhydride with a-naphthol for a short time t o the boiling point of the latter Grabowski (Ber. 1871 4 661) obtained what was apparently an anhydride of a-naphtholphthalein. This substance which had the composition C28H16Q3 was insoluble in alkalis and was of no particular interest. The true phthalein (C28H1804) which is readily soluble in alkalis with the production of an intense pure blue colour was shortly afterwards obtained by Grabowski ( R e r . 1871 4 725; 1873 6, 1065) from the interaction of a-naphthol and phthalyl chIoride. Sorensen and Palitzsch ( B i o c k e m . Zeitsch. 1910 24 381) have directed attention t o the great delicacy of a-naphtholphthalein as an indicator in alkalimetry and have described in detail a method for its preparation which differs but little from that recorded by Grabowski.Having recently received a request from one of my colleagues for a small quantity of this indicator which apparently is difficult to procure a t the present time a few experiments were made in order to ascertain if the substance could be prepared with the aid of phthalic anhydride which is so generally employed in the pre-paration of other phthaleins. Conditions necessary for obtaining the compound in very good yield were soon established and since a-naphtholphthalein has some special application in biochemistry it may be of interest and a saving of time to others to place on record the following details of its preparation.An intimate mixture of 7 grams of a-naphthol and 3.8 grams of powdered phthalic anhydride was introduced into a stout wide-mouthed testrtube and 0.75 c. c. of concentrated sulphuric acid was The most successful experiment was conducted as follows WERNER THE PREPARATION OF a-NAPHTHOLPHTHALEIN. 2 1 added. The tube which carried a thermometer was partly immersed in a beaker half full of water and heat( was applied until the contents of the tube had reached 60°; the heating was maintained for four hours during which period the temperature was never allowed to rise above 6 5 O . The mixture was well stirred a t intervals by means of the thermometer. The dark greenish-black viscous product was extracted with wat'er until free from sulphuric acid after which the semi-solid mass was digested a t about 70° with a litre of 0.5 per cent.solution of sodium hydroxide until the extraction of all material soluble in the alkali had been completed. The weight of pale yellow insoluble matter (Grabowski's anhydride') was only 0-8 gram. To the deep blue solution obtained after filtration dilute hydrochloric acid in quantity sufficient to neut'ralise about one-half of the sodium hydr-oxide present was added after which the liquid was saturated witlli carbon dioxide. The pale reddish-brown precipitate of a-naphthol-phthalein was collected washed redissolved in dilute solution of sodium hydroxide and reprecipitated as before. The weight obtained aft'er drying in a vacuum over sulphufic acid was 2-3 grams equal t o nearly 33 per cent.of the weight of a-naphthol tlaken. Sorensen and Palitzsch using phthalyl chloride obtained a yield equal to 30.5 per cent. calculated on the same basis. I n order to ensure a successful result in the preparation of a-naphtholphthalein by the method just described great care must be taken to avoid a rise of temperature above 6 5 O . Thus when the temperature was maintained at' 70-80° the yield was only about onehalf of that obtained a t 65O whilst' a t 80-90°, Grabowski's ( anhydride ' was almost the sole product. Excess of sulphuric acid was also found greatly to promote the formation of the anhydride at the expense of the phthalein. Attempts to hydrolyse Grabowski's anhydride to a-naphthol-phthalein by heating with dilute acids or alkalis under the ordinary pressure or in sealed tubes were unsuccessful. UNIVERS~TY CHEMICAL LABORATORY, TRINITY COLLEGE DUBLIN. [Received November 5th 1917.

ISSN:0368-1645    

DOI:10.1039/CT9181300020

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

22 SIMONSEN AND RAU THE NITRATION OF 5- AND IV.-The Nitration of 5- and 6-Acetylaniino-3 4-dimethoxybenzoic Acids and 4-Acetylarnino-V e r a t r o le. By JOHN LIONEL S~MONSEN and MADYAR GOPALA RAU. THE nitration of 2-acetylamino-3 4-dimethoxybenzoic acid and 3-acetylaminoveratrole was investigated by Gibson Simonsen and Rau (T. 1917 111 69) and in view of thel results obtained it appeared to us desirable to examine the products formed by the nitration of the two isomeric acetylamino-3 4-dimethoxybenzoic acids and OF 4-acetylaminoveratrole. NHAc"0Me NHAc/\C)Me NHAc/\UMe ,')OAT. OMe Obfe OM0 OM@ 1 I -+ NO () --+ NO" NOS(/ I + CO$ CO,H \/ NO . CO,H (111.) (1. ) (11). (JV- ) OMe OMe OMe OMe (V-) (VI.) I (VII.) (VIII. ) 5-*4 cetylanzino-3 4-dirnethoxy~enzoic mid (I) which was found to be most conveniently prepared from 5-nitrovanillin under the conditions described in the experimental part of this paper when treated with nitric acid gave a mixture of a nitroacetylamino-acid and a neutral substance which was insoluble in sodium carbonate solution.The latter substance was found to be 4:5-dinitro-3-acetylaminoveratrole' (111) a substance already described (Zoc. cit. p. 78). The nitroacetylamino-acid was readily shown to be 6-nitro-5-acetylamino-3 4-dimethoxybenzoic acid (11) since the amino-acid obt'ained from it on hydrolysis yielded when diazotised in alcoholic solution 6-nitroveratric acid (IV). When 6-acetylamino-3 4-dirnethoxybenzoic ucid (V) was nitrated, it was not found possible to avoid the displacement of the carboxyl group and the sole product of the reaction was 5-nitro-4-acetyZ-aminoveratrole (VI).The same substance was also obtained by the nitration of 4-acetylaminoveratrole (VII) . The constitution of the nitroawtylaminoveratrole was proved by the fact that whe 6-ACETYLAMINO-3 4-DIMETHOXYBENZOIC ACIDS ETC. 23 the amino-group was displaced by hydrogen 4-nitroveratrole ( V I I l ) was obtained. If these results are considered in the light of the suggestions made by the authors (T. 1917 111 224) it will be observed that the nitration of 5-acetylamino-3 4-dimethoxybenzoic acid proceeds exactly as might be expected. I n the formation of the nitroacetyl-amino-acid which is evidently the primary product of the reaction, the negative carboxyl group appears to exercise no direct orienta-ting effect except in so far as it neutralises the methoxy-group in the para-position with respect to it; the first nitro-group enters the ortho-position with respect to the acetylarnino-group and the para-position with respect to the second niethoxy-group.There appears to be no tendency for the elimination of a methoxy-group to take place as has been observed by various investigators in somewhat analogous cases and further nitration of the nitroacetyl-amino-acid merely results in the displacement of the carboxyl group with the formation of 4 5-dinitro-3-acetylaminoveratrole. The result obtained in the case of the 6-acetylamino-acid was somewhat unexpected. In view of the fact that both i n the case of 2-acetylamino-3 4-dimethoxybenzoic acid (IX) and of 3-acetyl-aminoveratrole (X) the nitro-group enters the para-position with respect to the methoxy-group which was in the ortho-position with respect t o the acetylamino-group it was thought that the 6-acetyl-amino-acid would yield the 2-nitro-derivative (XIII).OMe 0 Me GO,H 50 T 1 (XII) 0 All3 0Me OMe \/ /\o JJ 8 /\OM€? / )o A 1 H + f i q l ( N N A ~ NUA~(,NO 1 ~ N H A ~ C( '&i \/ (X). (XII.) (XIIT.) This did not prove to be the case displacement of the carboxyl group by the nitro-group taking place. This indicates clearly that an acetylamino-group exercises much less influence on a niethoxy-group when in the para-position with respect to it than when in the ortho. This view was supported by the fact that 4-acetyl-aminoveratrole gave on nitration an excellent yield of 5-nitro-4-acetylamiiioveratrole (VI) no trace of an isomeride being formed 24 SIMONSEN AND RAU THE NITRATION OF 5- AND EXPERIMENTAL.5-Amino-3 4-dimethoxybenzoic Acid. For the preparation of this acid the following method was found to yield the most satisfactory results (compare Hayduck Ber., 1903 36 2930). Vanillin (10 grams) was dissolved in ether (200 grams) and a steady stream of oxides of nitrogen (prepared by the action of dilute sulphuric acid on sodiurrt nitrite) was led through the well-cooled solution for two to three hours. After the addition of a little water the mixture was allowed to remain over-night when 5-nitrovanillin crystallised out. This was collected, and after washing with a little ether in which it was only very sparingly soluble i t was found to be pure melting a t 175-17GO.The yield was 8 grams. The methylation of 5-nitrovanillin offered considerable difficulty, and ultimately the followiiig method was adopted. The finely powdered potassium salt (dried at 130O) was suspended in dry toluene and after the addition of a slight excess of methyl sulphate, the mixture was heated a t 135-140° for two to three hours in an oil-bath when the scarlet potassium salt was completely decom-posed. The toluene was removed by distillation in a current of steam and the mixture of 5-nitroveratrole and 5-nitrovanillin was collected and triturated with dilute sodium hydroxide solution, when pure 5-nitroveratrole was obtained the yield being 50 per cent of the theoretical.By oxidation with potassium perman-ganate in alkaline solution a quantitative yield of 5-nitro-3 4-dimethoxybenzoic acid was obtained. The barium salt of the nitro-acid was readily reduced by means of an alkaline solution of ferrous hydroxide in the usual manner. On concentrating the solution of the barium salt of the amino-acid to a small bulk and rendering strongly acid with concentrated hydrochloric acid the hydrochloride separated in a yield of 50 per cent. of the theoretical. The hydrochloride was purified by crystal-lisation from a mixture of moist acetone and ethyl acetate or by solution in alcohol and precipitation with concentrated hydro-chloric acid when it was obtained in woolly needles decomposing a t 235O: 0.1094 gave 0.0694 A@.C1=15*6. C9H,,04N,HG1 requires C1= 15.2 per cent. Attempts to prepare a pure specimen of the amino-acid from the hydrochloride were unsuccessful the arnino-acid darkening with extreme readiness on exposure to the air. The pZa tinichloride separated in fine glistening yellow needle 6-ACETYLAMINO-3 4-DIMETHOXYRENZOIC ACIDS ETC. 25 which were readily soluble in water. It possessed no definite melt-ing point but became brown at about 180° and gradually blackened. It was not melted a t 270°. For analysis i t was dried a t looo: 0.1799 gave 0.0432 Pt. Pt=24*0. ( C9H,,0,N)2,H,PtCl requires Pt = 24.2 per cent'. 5-Acetylamino-3 4-dimethozybcnzoic acid (I) prepared in the usual manner from the hydrochloride separated from hot water in glistening fine needles containing one molecule of water of crystal-lisation which was lost on drying at looo.It softened atl 1 1 7 O and melted a t 1 2 6 O the anhydrous substance melting at 1 8 8 O : %0*4385 lost 0.0314 H,O a t looo. f-0.1059 gave 0.218 GO and 0.0511 H,O. H,O = 7.2. C=55*3; H ~ 5 . 4 . C,,H,,O,N,H,O requires H,O = 7.0 per cent. C,,H130,N requires C = 55.2 ; H = 5.4 per cent, K i t l a tion of 5-A cetylumino-3 4-dimet hoxyb enzoic Acid. 6-Nitro-5-acetylamino-3 4-dimethozybenzoic A cid (11) and 4 5-Dinitro-3-ncetylaminoverntrole (111). In one experiment 5-acetylamino-3 4-dimethoxybenzoic acid (2 grams) was gradually added t o nitric acid (D 1-52; 6 grams), which was kept well cooled in a mixture of salt and ice. The reaction proceeded with considerable evolution of gas and after ten minutes the extremely viscid yellow liquid was poured on ice, when an oil separated which gradually solidified.The solid was collected washed with a little ice water and triturated with a dilute solution of sodium carbonate. The insoluble residue (0.9 gram) was crystallised from acetic acid when itl was obtained in glistening needles melting a t 241° and was found to consist of 4 5-dinitro-3-acetylaminoveratrole identical in every respect with the substance described by Gibson Sirnonsen and Rau (T. 1917, 111 78). (Found N=15.1. Calc. N=14.7 per cent.). The alkaline solution from which the dinitro-compound haJ been separated was acidified when the nitroacetylamiizo-acid was pre-cipitated in pale brownish-yellow crystals (1.2 grams).It was purified by crystallisation from dilut'e alcohol : 0.143 gave 14 C.C. N a t 32O and 760 nim. 6-iVitro-5-ucetylamino-3 4-dirnethoxyb enzoic acid crystallises in straw-coloured needles which decompose at 220-221°. It is readily soluble in alcohol or acetone very sparingly so in water benzene, chloroform or ethyl acetate but mme readily so in hot water. N=10*3. Cl,Hl,O,N requires N = 9.9 per cent. * Air dried. Dried at looo 26 SIMQNSEN AND RATJ THE NITRAT'ION OF 5 - ANU When heated on the water-bath with hydrochloric acid (50 pei-cent.) for some hours it gradually passed into solution xnd 011 rieutralising the excess of mineral acid with ammonia the ctiirilto-acid separated as a pale yellow crystalline powder. It was re-crystallised from a mixture of ethyl acet'ate and benzene: N=12.4.0.13 gave 15 C.C. N a t 30° and 760 mm. C,H,,0,N2 requires N = 12.2 per cent. 6-il'itro-5amino-3 4-dimethoxyb eiixoic acid crystallises in iridescent yellow prismafic needles which melt a t 1 4 8 O . " It is readily soluble in acetone ethyl acetate or alcohol but very sparingly so in water or benzene. 7 h z o tisn t i o 12 of 6-Nitro-5 -amin 0-3 4 -dim e t ?L o,xyb e nx o i c A cid . 6-Nitro-3 4-dimethoa?/benzoic Acid (IV). The amino-acid (0-5 gram) was dissolved in alcohol (5 c.c.) and, after the addition of sulphuric acid (1 gram) amyl nitrite (I gram) was added to the well-cooled mixture. The clear solution gradu-ally became cloudy and after some minutes the sparingly soluble diazonium salt crystallised.This was decomposed on the water-bath and on pouring into water a reddish-yellow solid separated, which was found t o be a mixture of 6-nitro-3 4-dimethoxybenzoic acid and a phenolic acid. It was therefore dissolved in alkali and niethylated with methyl sulphate in the usual manner treated with potassium permanganate to remove a trace of phenolic acid, and the solution filtered and concentrated when on acidifying the nitro-acid was obtained as a caseous white precipitate. It was re-crystallised from hot water when it was obtained i n fine needles melting a t 185-157O and this melting point was unaltered 011 admixture with a specimen of the 6-nitro-acid from another source. As a further proof of the constitution of this acid the' methyl ester was prepared.It crystallised in finel needles melting a t 143-144O, which is the melting point of methyl 6-nitro-3 4-dimethoxy-benzoate. 6-A cetylciirzino-3 sl-di.metJ~osy2,etlzoic Acid (V). This substance which does not' seem t o have been prepared previously was rsadily obtained when the hydrochloride of the amino-acid (Ber. 1876 9 942) was warmed with acetic anhydride. It was crystallised from dilute acetic acid when it was obtained in colourless irregular prisms decomposing a t 228O : plates and melted at about 180". but it was not obtained in sufficient qiiantity for analysis. * On 0 1 i ~ occasioii :I t r i h c t . o f ati auicl was isolatctl whiclr crystdlisctl in I t was probably the isomeric nitro-aci 6 -ACXTYLAMINO-3 4-DIMETHOXYRENZOIC ACIDS ETC.2'9 0.1857 gave 10.4 C.C. N a t 30O and 760 mrn. N = G.0. C,,I'I130,N requires N = 5.9 pe'r cent. Nitration of 6-Acetylanzino-3 4-dimethoxyb enzoic Acid. 5-Nitro-4-acetylaminoveratrol e (VI). A large number of experiments were made with the view of finding a method for nitrating the amino-acid without the elimina-tion of the carboxyl group but' in this we were unsuccessful. I n one experiment the finely powdered acetylamino-acid (2 grams) was slowly added t o nitric acid (D 1.42; 6 grams) well cooled in a mixture of salt and ioe. The acid dissolved with the evolution of gas and in a short time the whole mass became pasty owing to the separation of the nitro-derivative. After fifteen minutes the mixturel was poured on ice and thel yellow solid collected (2 grams).It was found to be quite homogeneous and was purified by crystal-lisation from alcohol : 0.1061 gave 11.8 C.C. N at 30° and 759 nim. 5-Niti.o-4-acetyZami1ioz.el.crfl.olf separates from alcohol in golden-yellow needles melting a t 196O. It is insoluble in water sparingly soluble in cold alcohol or acetic acid but more readily so in hot alcohol or acetic acid. 5-Nitro-4-am.iizove7.atroZr:.-This substance was readily obtained when the foregoing compound was dissolved in sulphuric acid (90 per centl.) and the solution heated at 100O for ten minutes. On pouring into water the nitroaminp separated as a yellow powder, and was purified by crystallisation from alcohol : N = l l . 9 . C,,H,,O,N requires N = 11.7 per cent. 0.1054 gave 14 C.C. N a t 30° and 759 nim.C8H,,0,N2 requires N = 14.1 per cent. 5-Mitro-4-aminoverntrole crystallises in terra-cotta-coloured needles melting at 171O. It is readily soluble in acetone hot alcohol or hot ethyl acetate but very sparingly so in benzene or chlorof orrn. It dissolves readily in concentrated mineral acids but is reprecipitated,on dilution. The high melting point of this nitro-amine is somewhat remarkable and in order to make certain that no change had taken place on hydrolysis it was treated with acetic anhydride when the acetyl derivative melting a t 1 9 6 O was obtained. The benzoyl derivative crystallised from alcohol in sulphur-yellow woolly needles melting a t 153-154O. When diazotised with amyl nitrite in alcoholic solution in the usual manner the nitroarnine gave a nearly quantitative yield of 4-nitroveratrole melting a t 95-96O.(Found N = 7-6. Calc., N = 14.3 28 SENIER AND GALLAGHER STUDIES IN N ~ 7 - 6 per cent.) stitution. There cati therefore he no doubt as to its con-4 -A nz i I I o v e m t r 01 e . The preparation of 4-aminoveratrole by the reduction of 4-nitro-veratrole offered some difficulty owing to the tendency for chlorination to take place simultaneously. Ultimately the follow-ing method was found to give fairly satisfactory results. 4-Nitro-veratrole (10 grams) was mixed with tin (16 grams) and after the addition of a trace of graphite (compare Pinnow J . p. Chem., 1901 [ii] 63 352) hydrochloric acid (50 C.C. of 50 per cent.) was added and the mixture heated on the water-bath for from two to three hours. The yield of 4-aminoveratrole isolated in the usual manner was about 50 per cent. of the theoretical. nitration of 4-Acetylarninoue,rat~.o7e. To nit'ric acid (D 1.4; G grams) well cooled in a mixture of salt and ice finely powdered 4-acetylaminoveratrole [VII] (2 grams) was gradually added. The nitration proceeded with considerable evolution of gas and in a short' time the whole mass became pasty. After fifteen minutes the mixture was poured on ice when a yellow solid separated. This was collected and found t o melt at 195O (1.4 grams). It was crystallised from alcohol when it was obtained in golden-yellow needles melting a t 196O and was found to be identical in every respect with the 5-nittro-4-acetylamino-veratrole obtained by the nitration of 6-acetylamino-3 4-dimethoxybenzoic acid (see above) : 0.0727 gave 0.1337 CO and 0.0352 H,O. C=50*1; €I=5*3. C,,H,,O,N requires C = 50.0 ; €I = 5.0 per cent. THE PRESIDENCY COLLEC E, MADRAS. [Received November 6th 1917.

ISSN:0368-1645    

DOI:10.1039/CT9181300022

出版商:RSC    

年代:1918

数据来源: RSC

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28 SENIER AND GALLAGHER STUDIES IN V.-Studies in Phototyopy and Thewnot?*opy. Part 2 4 - Dih yd ~"oxy- VUI. bmzglidcn eamin es. Cinnam y lideneamines. By ALFRED SENIER and PATRICK HUGH GALLAGHER. THIS communication is a report of further study of t,he condensa-tion products of aromatic aldehydes with amines the anils or Schiff's bases wit,h a view to the discovery and special examina-tion of such as might exhibit phototropic or thermot'ropic change PHOTOTROPY AND THERMOTROPP. PART VIII. 29 Previous communications have shown that whilst compounds of this class are generally thermotropic they are not phototropic unless they contain an hydroxyl group in an ortho-position with respect to the aldehyde group of the benzylidene nucleus. More-over the property appears to be inhibited by the entry into the nucleus of such substitnents as bromine methyl or methoxyl.With one possible exception (Foresti A t t i R. Accud. Lincei, 1914 [v] 23 ii 270) phototropy has not been observed except in the case of solids and it has been suggested (Senier and Shep-heard T. 1909 95 1944) that i t is not due to intramolecular change but to reversible extra-molecular rearrangementl of the molecules into molecular aggregates. In order to determine if possible whether this explanation or some other is the true one, we are endeavouring to discover further instances of phototropic compounds for study. We wished t o examine the 2-hydroxycinnamylidenearnine~~ but practical difficulties a t the present time have prevented us. This paper contains however an account of the preparation and in-vestigation of the simpler cinnamylideneamines and also of 2 4-dihydroxyben~ylidenearnines~ which latter contain in addition t o an o-hydroxyl group another hydroxyl group in the p-position.None of the compounds is phototropic between “ t h e lower temperature,” thatl of solid carbon dioxide and (‘ the higher l,einperature,” just below their melting points. Prolonged ex-posure to actinic light however induces permanent polymorphic change i n many instancee. Thermotropy was detected in nearly all cases. Differences of colour in solution depending on the solvent employed were generally observed. The solutions in acetic acid or chloroform were usually deeper in colour than those in light petroleum benzene or acetone (compare Senier and Shep-heard T.1909 95 1943). Trituration appears to yield a poly-morphic variety in the case of cinnamylidene-m-bromoaniline but was not otherwise observed. No tritoluminescence was detected. The 2 4-dihydroxybenzylidene derivatives exhibit marked dichroism in solution. They are green in very thin layers or in dilute and yellow in thicker layers or when the solutions are concentrated. The green colour of thin layers appears to partake of the character of fluorescence for i t persists when viewed with light from a blue or violet light-filber. Most of the compounds are readily formed by mixing alcoholic solutions of the aldehyde and base. The ortho-substit’uted anilines, however combine with the aldehydes only on prolonged heating a t looo.Attempts t o prepare mono-derivatives of phenylene arid naphthylene-diamines resulted in the formation of di-derivatives 30 SENIER AND GALLAGHER STUDIES IN The source of actinic light employed was direct sunlight or a mercury lamp. The compounds dissolve generally in the usual organic solvents ; any important exception is noted. Cinnamylideneaniline C,H,*C‘H:CH*CH:N*C,H (Dobner and Miller Ber. 1883 16 1665) consists of yellow plates which melt a t 109O (corr.). It is changed into a deeper coloured polymorphic form by the prolonged action of actinic light’ and is thermotropic a t both “the higher ” and “ the lower temperatures.” CirznamyZicEcizechZoroaiziZ~~~es C,H,*CH:CH*CH:N*C,H,C1. Cinnamylidene-o-chloroun~lar~e at first’ separates mixed with tarry matter which may be removed by careful washing with alcohol light pet’roleum or ether.After several crystallisations, it becomes nearly colourless the crystals showing a pale greenish-yellow tinge. It melts at 63.5O (corr.): C,,H,,NCl requires N = 5.80 per cent. 0.1324 gave 7 C.C. N a t 1 7 O and 767 mrn. This compound shows no change of colour by the action of actinic light or by changes of temperature. Cinnamylidene-p-chloroaniline (James and Judd T. 1914 105, 1430) crystallises in pale yellow or as in our experiment in nearly colourless plates which melt a t 1 0 7 O (corr.). It is not phototropic, but exhibits thermotropy at “the higher,” and in a less degree at “ the lower temperatures.” N=5*96. Cinmmylidene bromoa nilines C,H,*CH :CH*CH:N-C,H,Br. Ginnumylidene-o-bromoaniline separates from alcoholic solution 0.1668 gave 7.1 C.C.N a t 19O and 762 mm. Slight thermotropy was detected both above and below the ordinary temperature. Cinnamylidene-m-bromoaniline (James and Judd T . 1914 105, 1434) consists of pale yellow plates which melt at 1 2 2 O (corr.). (The above authors found 115-1 16O.) Prolonged action of actinic light produces a slight permanent deepening of colour and slight evidence of thermotropy was observed. Cinnamylidei~e-p-bromon.l-Lliline crystallises from alcohol chloro-form or benzene in pale greenish-yellow plates which melt at 120° (corr.). A permanent deepening in colour occurs when this corn-in pale greenish-yellow clusters which melt at 7 4 O (corr.) : N=4.98. C,,H,,NBr requires N = 4-88 per cent PHOTOTROPY AND THERMOTROPY.PART VIII. 31 pound is submitted to the prolonged action of actinic light and thermotropy was observed a t the lower temperature.” 0.1402 gave 5.9 C.C. N a t 16O and 768 mm. N=4.885. C15H13NBr requires N = 4.88 per cent. Cirmamylidene t olzcidines C6H5*CH :CH-CH N*C,H,Me . Cinnamylidene-o-t,oluidine (James and Judd T. 1914 105, 1433) which melts a t 73O is not affected by actinic light or by temperature changes under its melting point. Cinnamylidene-m-toluidine is neither phototropic nor thermo-tropic (Senier and Shepheard T. 1909 95 1955). Cinnamylidene-ptoluidine (Tinkler T. 1913 103 894) consists of pale greenish-yellow plates which melt a t 83O (corr.). Slight deepening of colour occurred by the prolonged action of actinic light.No evidence of thermotropy was observed. Cinnamylide ne tiitrotoluidines C6H5*CH:CH.CH :N-C,H,Me*NO,, CinlzamyEidene-4-nitro-o-tol~i~~~ne forms pale greenish-yellow 0.1140 gave 10.4 C.C. N at 1 9 O and 757 mm. This compound forms deeper coloured solutions in alcohol or It is not photo-CinrLamylidene-2-nitro-p-toluidine crystallises from alcohol in 0.2388 gave 21.2 C.C. N a t 15O and 767 min. C,,R,,0,N2 requires N = 10.50 per cent. This compound is not affected by actinic light but exhibits thermotropy a t both ‘‘ the higher ” and “the lower temperatures.” Cinnamylidene-nz-nitroaniline (James and Judd 1914 105, 1434) is not thermotropic nor is it affected by actinic light. Cinlzamylidene-p-anisidirLe C,H,-CH:CH-CH:N*C,H,*OMe is obtained from solutions in alcohol in large yellow plates which melt at 119O (corr.): clusters which melt at 126O (corr.): N=10*54.C,,H,,O,N requires N = 10.50 per cent. acetic acid than in the other ordinary solvents. tropic but is thermotropic at “ t h e higher temperature.” pale yellow leaflets which melt a t 108O (corr.) : N=10+58. 0.1106 gave 5-6 C.C. N a t 1 6 O and 759 mm. C,,H,,ON requires N = 5.93 per cent. This base dissolves sparingly in cold alcohol. Acetic acid changes the yellow crystals into a scarlet probably Jim orphic vcirirty which we propose to examine further. It is not affected N=6.00 32 SENIER ADD GALLAGHER STUDIES IN by actinic light but is slightly thermofropic a t “the lower temperature.” Cinnamyliderhe-p-phe?betidine C,H,*CH:C~~*CH:N.C,H,.OMt,, consists of pale green lustrous plates which melt a t 1 0 8 O (corr.).Like the preceding base acetic acid changes it into a red dimorphic variety which crystallises in prisms. Itl is slightly thermotropic, but is not phototropic: 0.1328 gave 6.2 C.C. N at 1 5 O and 767 mm. CinlzurnyZider~e-p-x~Zid~?~e) C,H,*CH:CH*CH:N*C,H3Me2 separ-N=5.58. Cl7H17ON requires N = 5.58 per cent. ates in pale yellow needles which melt a t 111.5O (corr.) : 0,0856 gave 4.3 C.C. N a t 1 5 O and 764 mm. This compound is not affected by actinic light but exhibits slight’ thermotropy a t both “the higher ’’ and “ the lower tempera-turM. ” Cinnamylideneq-cumidine C,H,*C€I:CH*CH:C,H,Me (Schiff, Annalem 1887 239 384) which melts a t 105O is not affected by actinic light but is thermotropic a t both “the higher” and “the lower temperatures.’’ N=6*08.C17H17N requires N=5*95 per cent. Cin namylideneni tro-$-c u-midin e, C,H,*CH :CH*CH:N*C,H&le,-NO, -This base separates at’ firsti in orange-red needles. After several recrystallisations yellow crystals are obtained which revert to orange-red on keeping. After further recrystallisations however, the product retains its yellow colour. It melts a t 1 1 7 O (corr.). Actlinic light has no effect on this base nor is i t thermotropic: 0.2424 gavel 20 C.C. N a t 1 7 O and 759 mm. C”,&@&,N2 requires N = 9-53 per cent. Cinnamylidene-fi-napht hylamine C,H,*CH:CH*CH:N*Cl,H7 (Schiff A n n u l e l t 1887 239 384) is stated to melt a t 95-96O. Our specimen melts a t 124O (corr.).(Found N-5.41. C,,H,,N requires N = 5-46 per cent .) This base is neither phototropic nor thermotropic but by the prolonged action of actinic light it changes into a deeper coloured polymorphic form. CinnamylidenecamphyEanzine was prepared but as i t proved to be a liquid and the quantity was small we did not proceed with i t further . N=9*63. Dieinnam ylidene-p-phenylenediamine, (C,H,*CH:CH*CH:N)2CBH4 PHOTOTROPY AND THERMOTROPY. PART VIII. 33 separates from alcohol as a pale yellow powder which melts at 209O (corr.). It is not phototropic or thermotropic: C2,H2,N requires N = 8.34 per cent. (C,H,-CH:CH*CH :N)2C10H6, separates readily in brick-red crystals but on being left in contact with the solvent they change into a viscous red tar.By quickly recrystallising several times from alcohol and subsequently wash-ing with ether and drying the compound melts atl 136O (corr.) : 0.1802 gave 12.6 C.C. N a t 17O and 760 mm. Dicinnamy lidene-o- nap h t h y l e nediamine, N=8*04. 0.1364 gave 8.7 C.C. Nz a t 2 1 O and 766 mm. C,,H,,N requires N = 7.74 per cent. This compound dissolves in the usual organic solvents giving blood-red solutions ; the solutions in ethyl methyl or amyl alcohols, and in ether ethyl acetate or acetone exhibit a strong blue fluorescence; those in toluene or xylene are slightly fluorescent,; those in benzene or nitrobenzene are not fluorescent. On keeping, even in the dry state this base changes into a dimorphic variety of a yellowish-grey colour which melts a t 1 1 2 O (corr.).When dis-solved this modification appears to revert t o the original compound. Dicinnamylidenebenzidine (C,H,*CH :CH*CH:N*C,H,) (Schiff, Aqznalen 1887 239 385) is obtained easily as a yellow powder. It melts a t 249O (corr.). Acetic acid dissolves it forming a red solution but it is only sparingly soluble in the other organic solvents. It is thermotropic a t " the higher temperature," but is not affected by actinic light: N=7*66. 0.1098 gave 6.4 N a t 16O and 768 mm. C,,,H,,N requires N = 6.80 per cent. 2 4-Bihydroxy b enzylideneaniline (OH),C,H,*CH:N-C,H, forms pale greenish-yellow needles from solution in most organic solvents. It melts a t 99'5O (corr.) (Dimroth and Zoeppritz Ber. 1902 35, 995 give 125-126O and Gattermann dnnalefi 1907 357 336, gives 131O).C,,H,,O,N requires N = 6.57 per cent .) This compound is thermotropic both a t the higher and the lower temperatures; it is not phototropic but changes into a deeper coloured polymorphic form on prolonged exposure to actinic light. N=6.92. (Found N = 6.39. 2 4-Dihyd/roxybenaylidene-o-bromoani~i~~e, ( OH)2C6H3*CH:N*C6H,Br. -The product consisted of a reddish-yellow tar which eventually solidified and yielded by treatment with solvents a reddish-yellow, VOL. CXIII. 34 STUDIES IN PHOTOTROPY AND THERMOTROPY. PART VIII. amorphous powder ; this separated from benzene solution in crystals melting a t 9l0 (corr.) : 0.1210 gave 5.0 C.C. N a t 22O and 762 mm. This compound is thermotropic both atl N=4.68. C1,Hl,O2NBr requires N = 4-79 per cent.the higher ” and “ the lower temperatures,” and yields a polymorphic form by long es-posure t o actinic light but is not phototropic. 2 4-Dihy~roxybenzylidene-m-bromoarLililze.-The first product’ of the reaction is a deep red liquid which soon solidifies. The substance separates from benzene solution in deep yellow crystals melting a t 111’5O (corr.) : 0.2829 gave 11.8 C.C. N at 15O and 751 mm. C,,H,,O,NBr requires N = 4-79 per centi. The yellow crystals are changed into a red dimorphic form by contact with acetic acid or benzene and an orange-coloured product was noticed on prolonged exposure t o actinic light and also on trituration. It is notl phototropic but exhibits thermotropy at (‘ the lower temperature.” 2 4-Dihydroxyb enzylidene-pbrornoaniline crystallises in pale greenish-yellow needles from alcohol chloroform or acetone or in plates from acetic acid or benzene.N=4*86. It melts at’ 124O (corr.) : 0-1840 gave 7.6 C.C. N a t 16O and 751 mm. This base is not phototropic but changes to a deeper coloure(1 It is thermo-N=4*78. C13H,,0,NBr requires N = 4.79. polymorphic form on long exposure t o actinic light. tropic a t both ‘‘ the higher ” and “ the lower temperatures.” 2 4-Dihydroxybenzylidene-m-tol,uidine, ( OH),C,H3*CH :N* C,H,Me. -The first product of the reaction consisted of a mass of scarlet crusts and yellow needles (dimorphic forms). On recrystallisation, the whole separated in yellow needles which melt a t 137O (corr.) : 0,0976 gave 5.1 C.C. N atl 20° and 762 mm.C14H130,N requires N= 6.17 per cent. This compound is thermotropic both a t “the higher ’’ and “the lower temperatures ” ; it is notl phototropic but acted on by actinic light yields a deeper coloured polymorphic form. 2 4-Dihydroxy b enzylz’dene-P-napht hylawzim, N=6*05. (0 H),C,H,*CH :N separates from acetone in yellow needles or from alcohol in yellow plates. It melts a t 160*5O (corr.): 0-1220 gave 5.6 C.C. N a t 20° and 762 mm. N=5*31. C17H,,0,N requires Nz5.32 per cent STUDIES ON THE SULPHONATION OF P-NAPHTHYLAMINE. 35 This compound is not affected by actinic light but is thermotropic 2 4-Dihyd.roxybenzyl~denecamphylamine, a t the higher temperature changing to an orange thermot’rope. (OH),C,H,*CH :N*CH,-C,H,,. -Pale gre’enish-yellow needles of this compound separate from solutions in alcohol chloroform benzene or acetone. These melt a t 133O (corr.). I n acetic acid it dissolves forming a colourless solution-a dimorphic form-but from this solution we were only able t o obtain a small quantity of a yellow oil. The yellow needles are not phototropic but are slightly thermotropic both a t “the higher” and a t “the lower temperatures”: C,,H,,O,N requires N = 5.13 per cent. 0.1537 gave 7 C.C. N a t 1 5 O and 768 mm. N=5*04. UNIVERSITY COLLEGE, GALWAY. [Received December 3rd 1917.

ISSN:0368-1645    

DOI:10.1039/CT9181300028

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

STUDIES ON THE SULPHONATION OF P-NAPHTHYLAMINE. 35 VI.-Studies on the Xulplzonation of &Nuphthylamine. By ARTHUR GEORGE GREEN and KAPILRAM H. VAKIL. THE isomeric P-naphthylaminesulphonic acids are of considerable importance in the dye industry partly as such and partly for the preparation of other intermediate compounds. It therefore appeared to be of interest to submit the sulphonation of 6-naphthyl-amine t o a more detailed study than has yet been published, directed t o ascertaining the mechanism of the reactions involved, the circumstances favouring the production of the respective isomerides and the conditions for the conversion of one into another. Previous workers have shown (Badische Anilin- & Soda-Fabrik, D.R.-P. 20760; Dahl & Co. E.P. 7712 of 1884; Bayer and Duis-berg Ber.1887 20 1426; Forsling Rer. 1886 19 1815; 1887, 210 2103; Green T. 1889 55 33) that the sulphonation of P-naphthylamine gives rise t o four moriosulphonic acids originally ciist'inguished by the prefixes a 6 y and 6 t o which principally through the researches of Armst'rong and Wynrie (P. 1888 4, 105 ; 1889 5 48; 1890 6 138) the respective constitutions 2 8, 2 6 2:5 and 2:7 have been assigned. Of these isomeric acids, those containing the sulphonic group in an &position namely, the 2 8 and the 2 5 acids are simultaneously formed by sulphona-tion a t low temperatures ( 1 5 O to looo) whilst those containing a 36 GREEN AND VAKIL STUDIES ON THE the sulphonic group in a @-position namely the 2 6- and the 2 7-acids are formed simultaneously by sulphonation a t high tempera-tures ( 1 5 0 O and above).The two homonucleal sulphonic acids, 2 l and 2:4 have so far not been obtained by the sulphonation of 8-naphthylamine but are prepared by the action of ammonia on t'he corresponding sulphonic acids of &naphthol. E X P E R I M E N TAL. The sulphonations were carried out under exactly comparable conditions using a widemouthed round-bottomed flask of 300 C.C. capacity closed by a rubber stopper through which passed a glass tube terminating in a fine orifice in order to exclude the entrance of moisture during the operation. Ten grams of pure P-naphthyl-amine (twice distilled m. p. 112.) were used for each sulphona-tion. This was coarsely powdered so as to pass a 30-mesh sieve, and added during ten minutes t,o the sulphuric acid contained in the flask which was constantly shaken.The quantity of sulphuric acid used was four parte (40 grams) of 96 or 100 per cent. acid, or three parts (30 grams) of fuming sulphuric acid containing 20 per centl. of sulphur trioxide. As solution occurs the tempera-ture rises to nearly 60° and if sulphonation below this tempera-ture is desired the flask must bs cooled from time to time. As soon as solution was effected the flask was stoppered and immersed in an oil-bath the temperature of which was carefully regulated, where it was maintained a t the requisite temperature for the time specified. The product was then mixed with 100 C.C. of water and any lumps that were formed were broken down with a pmtie.After half an hour the precipitated sulphonic acid was collected on a Biichner funnel and washed with 75 C.C. of cold water care being taken to keep the surface unbroken. The precipitate was then transferred to a porcelain dish mixe'd to a fine paste with 50 C.C. of water the mixture being heated t o boiling and neutralised with 2N-sodium hydroxide using phenolphthalein as indicator. The quantity of sodium hydroxide required for neutnralisation indicates whethr the sulphonation has proceeded correctly and whether t>he product has been washed free from sulphuric acid. If an incorrect quantity was used the experiment was rejected. After cooling (and filtering to remove any 6-naphthylamine i f present) the solu-tion of the sodium salt was evaporated t o dryness on the water-bath dried sharply a t 100-105° and weighed.I n nearly every case the yield was about 96 per cent. of the theoreltical. For the separation and estimation of the isomeric acids use was made in the first place of the insolubility of the sodium salt o SULPHONATION OF P-NAPHTHYLAMINE. 37 the 2:8-isomeride in 90-94 per cent. alcohol (Dahl's method). The sodium salts entering into solution consist of the 2 5-isomeride, together with any 2 :6- and 2 :7-isomerides that may be present in the sulphonation mixture. For the separation of the former from the two latter a satisfactory method based on the different solu-bility of the silver salts was discovered. Whereas the silver salt of the 2:5-acid is fairly soluble in water the silver salts of the 2:6- and 2:7-acids are very sparingly soluble and separate as white silky precipitates on adding silver nitrate to even dilute solutions of the sodium salts.I n carrying out these separations the dry sodium salt; obtained as above was well powdered and a weighed quantity (15-16 grams) was extracted three times in succession with boiling 92-94 per cent. alcohol using a t each extraction about 90 grams of alcohol and boiling for fifteen t o twenty minutes. The filtrates were united the alcohol was distilled off and the soluble and insoluble sodium salts wer0 weighed after being dried. The latt'er consisted of practically pure 2 %sulphonate whilst the former was free from this salt but contained the remaining isomerides. For the estimation of the 2 6- and 2 7-acids 1 gram of the alcohol-soluble salt is dissolved in 20 C.C.of water in a small conical flask provided with a rubber stopper. Silver nitrate (5 to 10 C.C. of N/S-solution) is added the mixture well shaken and the precipitate collected after remaining for three or four minutes. The precipitated Pilver salt is washed with cold water and dissolved from the filter by ammonia. The solution is dilut,ed to 100-200 c.c. boiled and acidified with hydrochloric acid. The silver chloride is collected on a tared filter-paper washed with boiling water and weighed. From the weight of silver chloride obtained the percentage of 2:6- and 2:7-acids is calculated the difference being ths 2:5-acid. The hot filtrat'e on cooling deposits the 2:6- and 2:7-acids in glistening plates.The accuracy of the method was demonstrated on mixtures containing known proportions of the respective isomerides. The following numbers represent in nearly all cases the resiilts of a t least two concordant experiments. Effect of Temperature. I n this series of experiments sulphonation was effected with four parts of 96 per cent. sulphuric acid for five hours whilst the temperature was raised from 40° to 1 2 0 O 38 GREEN AND VAKIL STUDIES ON THE No. of 1 ............... 40' 2 ............... 60 3 ............... 80 4 ............... 90 5 ............... 100 6 ............... 120 experiment. Temperature. Percentage of isomeric acids in product. 2 8. 2 5 . 2 6 a n d 2 7 . I I \ 38 61.6 0.4 36 63.5 -44 55.3 0.7 42 57-3 -41 58.3 0.7 26 66.5 7.5 I n experiments 2 and 4 the amount of 2:6- and 2:7'-acids was not determined but an average value was assumed in arriving a t the percentage of the 2 5-acid.It is seen that the maximum yield of the 2 8-acid is obtained a t about 80° and diminishes with increase of temperature above this limit whilst itl is also somewhat' less a t lower temperatures. EfJect of Time. The sulphonation was effected a t 80° using the same proportion of 96 per cent. sulphuric acid as in the previous series but the time of reaction was varied from ten minutes to twenty-five hours. No. of 7 ............... 1 8 ............... 26 9 ............... 5 10 ............... 10 11 ............... 15 12 ............... 20 13 ............... 25 experiment.Time in hours. Percentage of isomeric. acids in product. 2 8. 2:5. 2:Gand2:7. A r \ 42 57.3 0.7 43 56.3 -44 55-3 0.7 43 55.1 1.9 37 61-0 -36 61.6 2.4 35 62.0 I In experiments 8 11 and 13 the amount of 2:6- and 2:7-acids was not determined but. an assumed value was used in arriving a t the percentage of the 2:5-acid. The sulphonation is just com-pleted within one hour a shorter time than this leaving a little unaltered j3-naphthylamine. In order to ascertain the effect of reducing the time of reaction to the lowest possible limit the following sulphonation was effected in about fifteen minutes at 50-60°. About 10 per cent. of the P-naphthylarnine remained unsulphonated and was collected after dissolving t,he acid in sodium carbonate solution.Pcrcentage of isomeric acids in product. experiment. temperaturc. 2 8. 2 5 . 2:6and2:7. Time and No. of / \ 14 ............... 15 minutes 28 71-2 0.8 A at 50-60" S UZPHONATION O F P-NhYHTHYLAMTNE. 3'3 E'fJect of Streitgth of Sulphziric Acid. In order to determine the effect of the concentration of the acid, sulphonations were conducted a t varying temperatures with 92, 96 (results already given) and 100 per cent. sulphuric acid and also with fuming sulphuric acid containing 20 per cent. of sulphur trioxide. With one exception the time of reaction was fixed a t five hours. I n the experiment marked with an asterisk it was only ten to fifteen minutes. The following table gives t'he percentages of 2:8-acid found. When 92 per cent. sulphuric acid was employed about 10 per cent.of /3-naphthylamine escaped sulphonation. Acid strength. Tempera-turo of sulphonation. 20" 40" 60" SO" 90" 100" 1 2 0 O 92 96 pcr cant. per cent. H,SO,. H,SO,. - 38 - 36 40" 44 - 42 I 41 - 26 - -100 20 per cent. por cent. H,SO,. SO,. 33 -39 35" 38 I 40 46 23 -32 I - -I The percentage of 2 6- and 2 7-isomerides was only determined in the alcohol-soluble sodium salts obtained from the series of sulphonations made a t SOo: With 92 per cent,. H,SO ...... 0.9 per cent. of 2 6- and 2 7-acids. .. 96 .. H,SO ...... 0.7 Y f 9 9 9 .. 100 .. H,SO ...... 1.5 .. 9 9 9 9 .. 20 .. so ......... 2.7 Y > 7 9 7 7 Conclzcsions from cxbove Results. It would appear frcjm the results obtained that within tempera-tures ranging from 20° t o SOo there is only a small variation in the proportion of the 2 8- t o the 2 5-isomeride which together constitute 97-99.5 per cent.of the entire sulphonat8ion product. The effect of variations in time is very similar; for periods betlween one hour and ten hours there is little difference in the proportion of the isomerides formed. Also within these limits of temperature and time the strength of the sulphuric acid appears t o exert but little influence with the exception that at. 80° a small rise in the amount of the 2 6- and 2:7-isomerides is notice-able with an increase in the concentration of sulphur trioxide. AIthough within the limits of time and temperature mentioned the proportion of 2:8- and 2:5-acids does not greatlly vary t'hh 40 GREEN AND VAKIL STUDIES ON THE lowest temperatures and shortest time of reaction seem to favour the production of the 2 5-acid.Above the limits of time and temperature defined a more marked variation becomes apparent the time and temperature a t which this change sets in being somewhat lowered as the concen-tration of acid is increased. In proportion as the tlemperature of 80° is exceeded or the sulphonation period (at 80.) is prolonged beyond ten hours the percentage of the 2 :$-acid falls whilst that of the 2:5-acid rises. Simultaneously therewith there is an in-creased production of the 2 6- and 2 7-acids the quantity of which reaches 7.5 per cent'. with 96 per cent. sulphnric acid a t 120O. This curious result can only be explained-in tkie f6llowing way : The proportion of the 2:s-acid existent a t any particular time and temperature may be regarded as a combination of two factors, namely ( a ) the proportion of the 2 8- and 2 5-isomerides formed simultaneously in the first instance; and ( b ) the amount of sub-sequent conversion of the 2 8- into the 2 5-acid.Whilst in regard to the first factor low temperature and quick reaction would seem to favour the formation of the 2 5-acid with regard to the second factor it would appear thatl the isomeric change of the 2:8- into the 2:5-acid only comes into evidence atl temperatures above 80° and for periods of heating (at 80.) more than ten hours. In other words it may be assumed that for temperatures below SOo the proportion of the 2 :8- and 2 :5-isomerides is a fixed one for a particular temperature the sulphonic group entering simuItaneously in the 5- and 8-positions.The proportion so fixed is fairly stable and can only be disturbed by heating t o temperatures above 80°, by prolonged action of sulphuric acid or by the use of a higher concentration of sulphur trioxide. The sulphonic group then commences to wander from the 8-position to the 5-position. Bxperiment s on Isomerisat ion. I n order t o test the validity of the foregoing hypothesis tlhs behaviour of pure 2 1- 2 8- and 2 5-acids towards sulphuric acid was studied under the conditions existent during sulphonation. Isomerisation of the 2:l-Acid-It has been suggested that the first stags in the sulphonation of P-naphthylamine may be the entry of the sulphonic group in the 1-position t o be quickly followed by a t'ransposition to the 5- and 8-positions.We have not been able in any instance to detect the presence of the Z:l-acid even when the sulphonation had been conducted a t the lowest possible tempera-ture and in the shortest time.* I f therefore the 2:1-acid is an * Following a suggestion by Mr. G. Lodge we have employed for the detection of the 2 I-acid the delicate reaction with bromine water in th SULPHONATION OF ,8 -NAPHTHY LAMINE. 41 intermediate product i t must undergo isomerisation with great rapidity. I n order to test this point the following experiments v17ere carried out. A.-A quantity (17 grams) of the pure sodium salt of /3-naphthyl-amine-l-sulphonic acid equivalent t o 10 grams of P-naphthylamine was heated with 40 grams of sulphuric acid (96 per cent.) for five hours a t 80°.Disappearance of the 2:l-acid only took place slowly. The product was worked up in the usual manner the resultant dry sodium salt; weighing 17 grams. On extraction with alcohol as usual 46 per cent. of the 2 &acid was obtained whilst the portion soluble in alcohol consisted of 52.5 per cent. of the 2 :5- and 1.5 per cent. of the 2 6- and 2 7-acids. B.-Another experiment was performed under the same condi-tions but! with 100 per cent. sulphuric acid. The change of the 2:l-acid again occurred very slowly and itl was possible to detect it by the bromine test even after three hours' heating. After five hours the transformation was complete and the product was then found to contain 40 per cent.of the 2 :%acid. C.-In a third experiment made with 96 per cent'. sulphuric acid the mixture was heated only for ten or fifteen minutea to 50-60°. I n this case 8 per cent. of P-naphthylamine was obtained, whilst! the greater part' of the product was unchanged 2 1-acid. From the formation of P-naphthylamine in experiment G and the production of the isomeric acids in experiments A and B in the same proportion as they are obtained by the direct sulphona-tion of P-naphthylarnine it may be inferred that the isomerisation is brought about by hydrolysis of the 2 1-acid to 6-naphthylamine and subsequent resulphonation. l n view of the considerable stabilitly of the 2 1-acid under the conditions of sulphonation it is clear that this acid cannot be an intermediate stage of the direct sulphonation.Hence in the latter the sulphonic group must enter the second nucleus directly and not through intermediate f ormat'ion of the homonucleal isomeride. Isomerisation of the 2 8-Acid.-The pure 2 8-acid was heated with sulphuric acid (96 per cent.) a t SOo for five hours. On work-ing up the product as usual it was found that 32 per cent. in one case and 27 per cent. in another had been converted into the 2 5-isomeride. The rate of this transformation under different cold by which l-bromo-8-naphthylamine is formed with the elimination of sulphuric acid. This reaction may also be used for the quantitative estima-tion of the 2 l-acid by weighing the sulphuric acid eliminated as barium sulphate.All other monosulphonic acids of B-naphthylamine give brominated acids without elimination of the sulphonic group (compare Vaubel Zeitsch. angew. Chem. 1900 14 686). a 42 GREEN AND VAKIL STUDIES ON THE conditions is shown i n the following series of experiments in which the pure sodium salt of the 2:$-acid (10 grams) was heated with sulphuric acid (80 grams) at varying temperatures and con-centrations for a period of ten hours. 2 5-Acid formed (con-taining less than 2 8-Acid 1 per cent.. of Temperature. unconverted. 2 6 and 2 7). 80" 78.5 21.5 90 72-8 27-2 With 80 uer 1 100 70.7 29.3 cent. H s ~ - 110 71-3 28.7 I 120 69.8 30.2 90 63.7 36.3 57.2 42.8 56.3 43.7 With 90per \ 100 62-3 37.7 cent. H,SO, Isomerisation of tJie 2 5-Acid.-In a similar series of experi-ments the pure 2:5-acid was subjected to the actrion of 96 per cent.sulphuric acid for five hours a t 80°. When worked up as usual the product gave a sodium salt completely soluble in alcohol and containing no 2 :%acid. Itl consisted almost entirely of un-altered 2:5-acid with a very small peroentage of t'he 2:6- and 2 7-isomerides. There is therefore no equilibrium established between the 2 8-and 2 5-acids in a sulphuric acid solution for the isomeric change occurs in one direction only namely from 2 8 t o 2 5. Relative Rate of Hydrolysis of the Zsomei-ic Sulplionic Acids. Whilst the sulphonic group in P-naphthylamine-l-sulphonic acid is somewhat readily removed the heteronucleal acids are more resistant although no data are available as to the relative facility with which the different isomerides undergo hydrolysis.It appeared probable that in such differences might be found an explanation of the above facts. Wit'h this object in view 2 grams of the pure sodium salt of the 2:&acid was heated with 20 grams of sulphuric acid (60 per cent.) in a small weighed flask on a sand-bath. The water was allowed t o evaporate slowly whilst from time to tlime samples were withdrawn and tested for ,8-naphthylamine by neut'ralisation with sodium hydroxide. N o hydrolysis occurred until the temperature reached 1 4 5 O . At this point which was found t o correspond with a concentration of 70 per cent. sulphuric acid the undissolved sulphonic acid passed into solution and a t the same time P-naphthylamine was formed SULPHONATION OF P-NAPHTHYLAMINE.43 I n a similar experiment with the 2 5-acid solution and hydro-lysis did not occur until a temperahre of 160° was reached corre-sponding with a concentration of 75 per cent. sulphuric acid. With the 2:6- and 2:7-acids no evidence of hydrolysis could be obtained even a t 175O. The relative facility with which the isomeric acids undergo hydrolysis to P-naphthylaxnine may there-fore be expressed thus : 2 1 > 2 8 ) 2 5 > 2 6 and 2:7. It may therefore be concluded that the gradual conversion of the 2 8- into the 2 5-acid during long heating with sulphuric acid a t temperatures of 80° to 120° is brought about by repeated hydrolysis of the 2 &acid and resulphonation of the P-naphthylamine pro-duced.Atl each resulphonation about 40 per cent. of 2:s- and 60 per cent'. of 2 5-acid is produced the former of which is again hydrolysed to B-naphthylamine and so on. Simultaneously with the conversion of the 2 8-acid into the 2:5-acid there also occurs to a less extent a transformatioii into the 2 6- and 2 7-acids. The last change which is negligible below 100-1 loo becomes considerable a t temperatures above 120° (especially when sulphuric acid of high concent'ration is employed), c* 44 STUDIES ON THE SULPHONATION OF P-NAPHTHYLAMINE. until a t 150-160° the 2 6- and 2 7-isomerides const'itute the main product of sulphonation. It appears probable that the formation of the latter acids is due to concurrent disulphonation and hydro-lysis in which sase the 2 6-acid would originate from the 2 8- and the 2 7-acid from the 2 5.The entire mechanism of thel sulphonatJon niay probably thsre-fore be expressed by the above scheme (S =SO,H) : Copper and Silver Salts of the Isomeric Sulph,onic Acids. I n seeking for a method of differentiating and estimating the isomeric acids we have studied the behaviour of solutions of their sodium salts towards copper sulphate and silver nitrate. The results are given in the following table\: Acid. cuso,. AgNO,. 2 8 Slowly deposits a reddish- Rather sparingly soluble orange precipitate. precipitate. 2 5 Deep red solution but No precipitation in moder-no precipitate. ately concentrated solu-tioiis. 2 6 Sparingly soluble yellow Very insoluble white,silky precipitate. precipitate. 2 7 Sparingly soluble orange- Similar but yellower. yellow precipitate. The silver salts of the four isomerides have been prepared in the solid stsate and form nearly colourless crystalline povders. On analysis the following results were obtained Found 2 8, Ag=32*7; 2:5 Ag=32.8; 2:6 Ag=32*9; 2:7 Ag=33.0. Calc., Ag = 32.73 per cent. Determination of their solubilities in water a t 1 5 O gave the following results the numbers indicating parts of water in which one part of the respective acid dissolves 2 8 300; 2 5 70 ; 2 6, 4900 ; 2 7 2800. We desire to express our thanks to Messrs. Levinstein Ltd., who have kindly supplied us with the materials rerquired in t'his investigation. DYESTUPFS RESEARCH LABORATORY, NUNICIPAL SCHOOL OF TECHNOLOGY, MANCHESTER. [Received November 12th 1917.

ISSN:0368-1645    

DOI:10.1039/CT9181300035

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

MASON AND WHEELER THE EFFECT OF TEMPERATURE ETC. 45 VI1.-The Eyect of Temperature and o f Pressure on the Limits of Injamrnability o f Mixtures of Hethane and Air. By WALTER MASON and RICHARD VERNON WHEELER. A ‘‘ LIMIT ’’ mixture of an inflammable gas with air or oxygen can be defined as such that the heab evolved by the combustion of one “layer” of the mixture is sufficient and only just sufficient to raise to its ignition-temperature the layer adjacent so that flame once started in such a mixture continues to be propagated pro-gressively throughout without the necessity for the continued presence of the source of heat that caused the inflammation. The self-propagation of flame through the mixture is only possible when the speed of reaction between the combining gases is sufficient to overcome any loss of heat by radiation convection, and conduction under the conditions of its combustion.The speed of reaction is dependent on the temperature that the portion of the mixture which is burning can impart to the portion that is about t o burn. It follows naturally therefore that the higher the initial temperature of the mixture the less is the propagation of flame dependent upon the heat generated by cornbustion so that the sff ect of increasing the initial temperature of mixtures of methane and air should be to widen their limits of inflammability lowering the lower and raising the upper limit. The effect of pressure on the limits is not so easy to forecast; in point of fact the results of experiments did not fulfil our anticipa-tions.It will bO best to leave discussion of the matter until the experiments have been described. The Z f f e c t of TempertrIrwe. The earliest systematic experiments on the effect of temperature on the limits of inflammability of gaseous mixtures seem t o have been by Bunte and Roszkowski in 1890 (J. Gasbeleuchtzmg 1890, 33 491 524 535 553). The mixtures were ignited electrically in a spherical vessel of 35 C.C. capacity. Apart from the fact that i t is impossible to judge accurately as to the propagation of flame in such a vessel something must have been radically wrong with Bunts and Roszkowski’s experimental arrangements for they recorded no marked change in the liinits for mixtures of methan 46 MASON AND WHEELER THE EFFECT OF TEMPERATURE and air when the initial temperature of the mixt<ures was raised from 1 5 O to 300O.Taffanel (Compt. rend. 1913 157 593) examined the effect of increased temperature on the lower limit for mixtures of methane and air by passing an elect'ric spark in the mixtares after intro-ducing them into a tube at the required temperature and observ-ing whether or no inflammation was propagated throughout the mixture. His results were as follow: Initial temperature of mix-Lower limit methane in air, ture ........................... 20" 175" 237" 312" 555" 690" per cent. ..................... 5.80 5.25 4.75 4.30 3.40 3-00 Taffanel did not state the dimensions of his tube the position of the point of ignition of the mixtures or the direction of travel of the flames; but from his results which as will be seen later, closely correspond with our own we conclude that a rather wide and short tube was used and that ignition was a t the top the flames being propagated vertically downwards.Burrell and Robertson (United States Bureau of Mines, Technical Paper No. 121 1916) repeated Taff anel's experiments, using a Hemps1 bulb of 100 C.C. capacity as the explosion vessel and igniting the mixtures near the top by an electric spark. The bulb was heated in an electric furnace and whether or 110 flame had propagated throughout) the mixture was judged by analysing the products of combustion. The results recorded were : Initial tempera-ture of mixture. 25O 200" 300" 400" 500" Lower limit, methane in aii., per cent. ...... 5.46-5.56 4.98-5-16 4.75-4.88 4.47-4.55 3.76-4.00 Accurate observation of the propagation of flame in a vessel that is totally enclosed in an electric furnace presents some difficulty.It is not easy to judge for example of the extent of downward propagation of flanie in a tube by an arrangementl of mirrors since the flame is viewed end-on; and analysis of the gases remaining after Aams has passed not altogether satisfactory as a means of judging whether flame has travelled or has just failed to travel throughout the vessel with lower-limit mixtures gives quite mis-leading result6 with the upper-limit mixtures where much of the combustible gas remains unburnt or incompletely burnt. For our experiments we have made use of the fact that the. limits for upward propagation of flame are wider than for down-ward propagation (T.1914 105 2591) to aid in observing whethe AND OF PRESSURE ON THE LIMITS OF INFLANMABILITY ETC. 47 or no flame travelled throughout the mixtures a t different tempera-tures in the manner described in the experimental portion of this paper. The criterion of inflammability adopted was self-propaga-tion of flame downwards. The gaseous mixtures were stored over FIG. 1. 800 700 600 i 2 3 P -+ 500 3 u u f 400 N 3 * * 300 F: hl 200 100 I n -n 0 n v d ' -4 0 n 0 + 0 5 10 15 20 25 30 Methane in limit mixtures. Per cent. a mixture of equal parts by volume of glycerol and water in glass gas-holders whence they were introduced into the previously heated and evacuated explosion vessel; they were thus saturated with water vapour a t the room temperature (ZOO).The results are given in the table that follows and diagrammatiically in Fig. 1 Initial temperature. 20° 100 150 200 250 300 350 400 500 600 700 750 800 Downward propagation of Aame in mixtures of methane and air. Methane per cent. Lower limit. Upper limit. 6.00 13-40 5.45 13.50 13.60 5.20 5-05 13.85 4.60 14.00 4-40 14-25 4.15 not determined. 4-00 14.70 3.65 15.35 3-35 16-40 3.25 18.75 23.60 29-00 A < I --The mixtures were allowed to remain during t W Q seconds in the explosion vessel (which had been previously brought t o the required temperature) before the passage of an electric spark t o cause ignition.This length of time was sufficient t o ensurethat the gases attained the temperature of the enclosure (compare Burrell and Robertson Zoc. cit. p. 6 ) and at' the same time except perhaps a t the highest temperatures did not admit of appreciable com-bustion on the surface of the vessel before the spark was passed. Consider first thO lower limit'. Progressive increase of the initial temperature causes a corresponding decrease in the amount of methane required in the air to enable self-propagation of flame t o take place. Our determinations agree closely with Taffanel's, and therefore disprove Bunte and Roszkowski's results. With an initial temperature of 750° a mixture cont'aining 3-00 per cent. of methane ignited without being sparked (and flame was pro-pagated throughout) as soon as it entered the explosion vessel, the rate of reaction on the surface of the explosion vessel a t this temperature being sufficiently rapid to cause self-heating of the mixture.At 700° no ignition occurred with a 3-20 per cent. mixture by tha walls of the vessel nor was flame propagated throughout such a mixture when an electric spark was passed; for complete propagation of flame a t this temperature the mixture had to contain 3.25 per cent!. of methane. Under the conditions of these experiments therefore the ignition-temperature (that is, the temperature a t which rapid self-heating takes place) of a 3 per cent. methane-air mixture can be regarded as between 700° and 750° (compare Taffanel Zoc. cit. p. 597). Just as the lower limit is lowered by increasing $he inikial temperature the upper limit is raised.The extent t o which the limit is raised increases regularly with the initial temperature o AND OF PRESSURE ON THE LIMITS OF INFLAMMABILITY ETC. 49 the mixture until 600° is exceeded after which there is a con-siderable rise! in the rate of increase (see Fig. 1). This is probably due to reaction between methane and oxygen on the surface of the explosion vessel being sufficiently rapid with high concentrations of methane atl temperatures above 600° to alter the constitution of the mixture during the two seconds that elapse between its introduction into the heated explosion vessel and the passing of the spark. We know that with excess of methanc in air carbon monoxide and hydrogen (both of which have very high upper limits of inflammability) persist in the products of combustion and it may be that the early production of these gases is the cause of the abnormal raising of the upper limit of inflammability of mixtures of methane and air a t temperatures greater than 600O.That com-bustion without flame takes place to an appreciable extent above 600° under the conditions of the experiments is shown by the fact that a t 700° no ignition could be obtained (with a mixture con-taining 18.70 per cent. of methane) if the mixture were left in the explosion vessel longer than five seconds before sparking whilst a t 750° an interval of only 1.5 seconds sufficed t o render a mixture containing 23.50 per cent. of methane uninflammable. I n each of these instances we can assume that the mixtures became un-inflammable by deprivation of oxygen consequent on its burning the methane.If therefore the formation of carbon monoxide and hydrogen by combustion of methane is the cause of the abnormal raising of the upper limit a t these high temperatures the effect is transitory. Hydrogen would be produced also by thermal decom-position of methane but the reaction is very slow at temperatures below 900°. I n any event it is clear that the results obtained a t temperatures above 600° do not properly represent the upper limits for self-propagation of flame in mixtures of methane and air. It may be mentioned that in no instance did ignition of and propagation of flame in a high-limit mixture take place through contact with the heated walls of the explosion vessel.At gooo, for example a spark had to be passed in order to cause flame t o travel through the mixture (containing 28.70 per cent. of methane). The Effect of Pressure. The effect of initial pressure above atmospheric on the limits of inff ammability of mixtures of hydrogen carbon monoxide and methane respectively with air has been studied by Terres and Plenz (1. Gasbeleuchtwng 1914 57 990 1001 1016 1025). The explosion vessel used was an iron cylinder 37 cm. long and 8 cm. in diameter. Ignition was by an electric spark a t a point 4 cm 50 MASON AND WHEELER THE EFFECT OF TEMPERATURE from the top of the cylinder and on its vertical axis. The critterion of inflammability was theref ore self-propagatio 1 of flame down-wards.Whether or no flame had passed throughout the mixture was judged by analysing the products of combustion. For methane (firedamp from Kissarmas Transylvania contain-ing 99.1 per cent. of methane) Terres and Plenz obtained the results shown in the tables that follow. Lower Limit. Methane in mixture. Per cent. 6.00 6.00 6.00 6-00 6-15 6-16 6.15 6-23 6.23 6.23 6-29 6-41 6.41 6-41 6-41 6.41 6.44 6.44 6-44 6.58 Ini t.i a1 pressure . Met ham burned. Mm. mercury. Per cent. 760 99 1520 22 2280 11 3800 7 1520 99 2280 26 3800 13 1520 100 2280 100 3040 31 3800 17 3800 4560 5320 6080 7600 100 98 50 30 12 5320 100 6080 95 6840 52 7600 100 Upper Limit. Initial pressure required for propagation of flame.Mcthanc in mixture. Per cent. Mm. mercury. 12.98 760 13-35 2280 13-65 4560 13.98 6840 With upper-limit mixtures according t o Terree and Plenz, either the mixture did not burn a t all under the conditions of their experiments or flame travelled throughout. No partial pro-pagation of flame took place as with the lower-limit mixtures. Their experiments can be summarised in %he statement that an increase of the initial pressure of the mixtures to 10 atmosphere AND OF PRESSURE ON THE LIMITS OF INFLAMMABILITY ETC. 51 raised the lower limit (downward propagation of flame) from 6.0 to 6.5 per cent. and also raised the upper limit from 13.0 to 14.0 per cent. Burrell and Robertson (Zoc. c i t . ) also studied the effect of pressure on the limits of inflammability of mixtures of methane and air using the same apparatus as for their work on the effect of temperature.Their experiments were mainly a t pressures less than atmospheric but they recorded that (‘ increasing the initial pressure u p to 5 atmospheres had no effect in changing the low limit of complete propagation ” (p. 10). Atl reduced pressures, they found that the limits were narrowed until a t pressures between 250 and 300 mm. of mercury it was impossible under the condi-tions of their experiments to obtain self-propagation of flame in any mixture of methane and air. Our experiments a t reduced pressures have been made with initial temperatures of 20° 250° and 500O. The same apparatus was used as for the experiments with different initial temperatures a t atmospheric pressure.The results are shown diagrammatically in Fig. 2. The fact’ thkt Burrell and Robertson were unable to obtain self-propagation of flame in any mixture a t pressures less than 300 mm. (at atmospheric temperature) whereas we found the limiting pressure to be 120 mm. is explicable on the assumption that their means of ignition was inadequate. For example a mixture of methane and air containing 9.5 per cent. of methane can be ignited a t atmospheric pressure by the secondary discharge from an (‘8-inch” X-ray coil a t a spark-gap of 1 mm. between platinum points when the current broken in the primary circuit (the trembler being locked) is about 0.5 ampere; but when the pressure of the mixture is reduced to 100 mm.it is necessary t o break a current of more than 7 amperes in the primary circuit of the same coil in order to obtain a secondary discharge atl a 1 mm. gap capable of igniting it (T. 1917 111 130). Burrell and Robertson’s results express not the limiting pressure for self-propagation of fEame ‘in any mixture of methane and air but the limitirig pressure for iyiiition by a secondary discharge of the particular intensity employed by them. Examination of Fig. 2 shows that a t atmospheric temperature the mixtures of methane and air in which flame is propagated (downwards) most readily as evinced by their having the lowest limiting pressure contain betwwn 8-75 and 9-40 per cent. of methane. The same conclusion can be drawn from the experiments by Burgess and Wheeler on ‘( limit ” mixtures of met’hane oxygen 52 MASON AND WHEELER THE EFFECT OF TEMPERATURE and nitrogen (T.1914 105 2596). Those experiments showed that by the gradual substitution of nitrogen for the oxygen in air the limits were narrowed until when the I‘ atmosphere ” contained only 13-45 per cent. of oxygen they lay between 6.50 per cent. (lower) and 6-70 per cent,. (upper) of methane. From the partial pressures of the gases the percentages of methane in the atmo-spheric air contained in these limit mixtures can be calculated the presence of the excess of nitrogen and of methane (above that FIG. 2. 800 700 600 $ 500 2 $ 400 8 E t 2 300 200 100 - L @i 2 4 6 8 10 12 1.4 16 Methane per cent. required for complete combustion by the oxygen) being regarded as equivalent t o a reduction of pressure.This calculation gives 9-2 per cent. of methane in air as the mixture that propagates flame most readily. The mixtures of methane and air most readily ignited by a secondary discharge or by the break-flash ( ‘ I momentary arc ”) produced a t the point of fracture of a metallic electric circuit (continuous current) contain between 8.0 and 8.6 per cent. o AND OF PRESSURE ON THE LIMITS OF INFLAMMABILITY ETC. 53 methane whilst the mixtures in which the “uniform move ment” of propagation of flame is most rapid contain between 9.5 and 10.0 per cent. of methane (T. 1914 105 2607). The range of mixtures over which propagation of flame occurs most readily thus lies mid-way between the range over which ignition (by electrical means) is easiest and the range over which the flames are fastest.It might be argued from this that ease of propagation of flame in a series of mixtures of methane and air is dependent about equally on the ease of ignition of the mix-tures and on the ratlio T-t/t-tI (see T. 1917 111 1044). It must be remembered however that the ignitibility of the mix-tures as shown by the intensity of the secondary discharge or the primary break-flash required to ignite them is not necessarily a measure of their ignitibility by heated gases during the propaga-tion of flame. The effect of raising the initial temperature of the mixtures is to widen the dilution limits a t all pressures and the limiting pressure for the self-propagation of flame in any mixture is lowered, though not to a great extent.A point in these experiments that should be noted is the small effect on the limits produced by reducing the initial pressures by as much as half an atmosphere; the effectl does not begin to be marked until the pressure is reduced below 300 mm. For experiments with initial pressures greater than atmospheric, we have used a tube of stout glass into which the previousl- pre-pared mixtures could be forced t’hrough a condensing syringe in the manner described in the experimental portion of this paper. The criterion of inflammability was as before propagation of flame downwards. The results were as follow: Initial pressure. Mm. mercury. 760 1250 2100 2900 3350 3750 4650 Lower limit.Methane per cent. 6-00 6.05 not determined. 6.20 6.25 not determined. 6.40 Upper limit. Methane per cent. 13.00 13.15 13-35 13.60 not determined. 13-80 14.05 We thus confirm Terres and Plenz’s results. For the lower-limit mixtures our values agree closely with theirs but we obtained a greater raising of the upper limitn by increasing the pressure than they recorded. This we think is due t o Terres and Plenz not having used a sufficiently powerful souroe of ignition for they have stated that the mixture.s either did not ignite a t all or flame travelled throughout them. This is contrary to our ex 54 MASON AND WHEELER THE EBFECT OF TEMPERATURE perience for we obtained .many mixtures at high pressures in which flame travelled only part of the way down the tube.Mix-tures of methane and air containing more than 11 per cent. of methane require a secondary discharge of considerable intensity to ignite them and the intensity required increases rapidly with increased methane content. Thus a mixture of methane and air, a t atmospheric pressure containing 12 per cent. of methane can be ignited by the secondary discharge from an “8-inch” X-ray coil across a spark-gap of 3 mm. when a current of 7.5 amperes is broken in the primary circuit (the trembler being locked), whereas a mixture containing 13 per cent. of methane requires 15 amperes and one that contains 14 per cent. 32 amperes. On the other hand an inereasei of the pressure (above atmospheric pressure) of any‘ of the mixtures renders it capable of being ignited by a discharge of slightly less inkensity (T.1917 111 411). It is easy to see therefore by the manner in which they ex-pressed their results how Terres and Plenz confused the inability of their secondary discharge to ignite some of their mixtures with incapability of the mixtures t o propagate flame They recorded, for example that a mixture containing 13-65 per cent. of methane did not propagate flame-did not burn at. all-when the initial pressure was 6 atmospheres; on raising the pressure to 7 atmo-spheres (when the mixture would be rendered more readily ignitible) flame was propagated throughout. Leaving differences in degree aside however we are in agree-menti with Terres and Plenz in observing a raising of both the lower and the upper limit with increased initial pressure (above atmospheric) and we find the results difficult t o explain.From the law of mass action we anticipated that increased pressure if it had any appreciable effect after atmospheric pressure had been passed would widen the limits on both sides. I f the widening of the upper limit be explained by mass action what is the reason for the narrowing of the lower limit ? According t o the kinetic theory loss of heat from gases by con-duction and radiation is independent of the pressure. When attempting to put this deduction from the kinetic theory to ex-perimental proof however Kundt and Warburg (J. de Physique, 1876 5 118) found that unless the pressure of the gas was low, the loss of heat due to conduction was masked by that’ arising from convection currents.It may be therefore as Terres and Plenz have suggested that the loss of heat from a gas a t high pressure is due to a greater extent t o convection than t o conduc-tion and increases with the pressure. According to this explana-tion the upper limit should also be narrowed and when hydroge AND OF PRESSURE ON THE LIMITS OF INFLAMMABILITY ETC. 55 or carbon monoxide is the combust,ible gas this is so. What must be regarded as the abnormal behaviour of mixtures of methane and air under pressure at' the upper limit requires further study. FIG. 3. c52 E X P E R I M E NTAL. The apparatus used for determining the limits of inflammability a t different temperatures and a t pressures less than atmospheric is shown in Fig.3. It consisted essentially of a U-tube of trans-parent quartz the limbs of which were close together fixed vertically in a tube furnace which could be heated electrically. One limb of the U-t'ube was 15 cm. long and had a capillar 56 MASON AND WH$ELER THE EFFECT 03 TEMPERATURE ETC. extension which was fitted by means of a ground joint< with a glass three-way tap of the form shown in the diagram to make connexion with either a vacuum pump or a gasholder arid mercury manometer. The other longer limb (35 cm.) was sealed a t the top which projected above the level of the furnace. The elec-trodes for igniting the mixtures were platinum wires led into the quartz tube immediately below the capillary extension through capillary sidetubes the upper ends of which were closed by plugs of glass ground in through which the platinum wires were sealed.The spark-gap was 4 mm. Since the limits for upward (or horizontal) propagation of flame are wider than for downward propagation a mixture which on ignition enabled flame to travel just the full length of the shorter limb of the U-tube easily carried flame up the longer limb and its appearance could be observed in the portion of the tube above the furnace either directly or as was found more convenient during experiments a t low pressures in a mirror inclined a t an angle of 4 5 O fixed above the top of the tube and enclosed in a darkened box. IgnitJon was caused by a shortl series of sparks from an “8-inch” X-ray coil with a current of 15 amperes in the primary circuit.Ths intensity of this discharge with a 4 mm. spark-gap was well in excess of the minimum required for the least easily ignitible mixtures whilst the length of the tube was sufficientl t o ensure that the initial impetus imparted to the flames by the source of ignition had died away before the bottom was reached. For the experiments at high pressures a tube of thick glass 18 cm. long and of 2 crn. internal diameter was employed fixed vertically. The tfube was provided a t the top with a high-pressure threeway tap of capillary bore t o make connexion with either a vacuum pump or a condensing syringe in communication with a gas-holder containing the mixture to be experimented with. A high-pressure tap a t the bottom of the tube communicated with a Bourdon pressure gauge.The electrodes were platinum wires sealed into the glass a t the top of the tube the spark-gap being 4 mm. A secondary discharge of the same intensity as for the experiments in the quartz tube was used to ignite the mixtures. The lower third of the tube was covered on the outside with black paper in which a horizontal slit 2 mm. wide was cut a t a distance of 15 cm. from the point of ignition; flame was judged to have travelled throughout the tube if it was observed to pass this slit. For the experiments a t different temperatures the method of procedure was to obtain two mixtures differing by 0.10 per cent. of methane the one enabling flame t o appear in the longer lim RELATION OF POSITION ISOMERISM TO OPTICAL ACTIVITY. 57 of the quartz U-tube whilst with the other no flame appeared. The mean percentage of methane in the two mixtures was taken as the limiting percentage. For the experiments a t different pressures two pressures were obtained for a given mixture differ-ing by 10 mm. of mercury a t pressures below atmospheric or by 50 mm a t higher pressures such that a t one pressure flame appeared in the prescribed manner whilst a t the other it did not'. The mean pressure was taken as the limiting pressure for the par-ticular mixture under the conditions of the experiment. The methane was obtained from a natural source of firedamp and purified by liquefaction. The mixtures with air (free from carbon dioxide) were prepared in glass gas-holders over glycerol and water and were analysed before use. [Received November 23rd 1917.

ISSN:0368-1645    

DOI:10.1039/CT9181300045

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

RELATION OF POSITION ISOMERISM TO OPTICAL ACTIVITY. 57 1711 I.-The Relation of Position IsomPl-ism to Optical Activity. P r w t iYI. The &hn,thyl Alkyl Esters of Tereplzthdic A cicl uzid itqv ItTirl.o-deriv~~2~~~~~. By JULIUS BERENU COHEN and HANNAH SMITH DE PENNINGTON. IN a former paper (T. 1916 109 222) a series of menthyl alkyl esters of phthalic and 3-nitrophthalic acid were prepared and examined with the following results whilst the free carboxyl group in the acid menthyl ester raises the niolecular rotation nearly looo ([M]ia - 332O) above that of menthyl benzoate ([MI;’ - 239O), the average rotation of seven menthyl alkyl esters ([MI,” -243’) did not differ greatly from that of menthyl benzoate-in other words the proximity of the carboxyl group raises the rotation, whilst that of the ester group produces little effect.I n the case of the parallel series of terephthalic esters which is the subject of the present paper the main difference in structure lies in the separation of the two carboxyl groups. One might therefore expect that like the menthyl alkyl esters of phthalic acid the alkyl ester group would have little or no influence on the active group and that the molecular rotations of these sub-stances would be of the same order as that of menthyl benzoate. This anticipation has been realised the average molecular rotation of seven menthyl alkyl esters of terephthalic acid being [MI - 2 5 4 O . In this case the average rotation is somewhat highe 68 COHEN AND DE PENNINGTON THE RELATION O$ than that for the corresponding menthyl alkyl phthalates ([M]io - 2 4 3 O ) .I n spite of numerous attempts it was found impossible t o obtain the acid menthyl ester in t’hhs crystalline state, but the amorphous product prepared by the semi-hydrolysis of dimenthyl terephthalate gave the correct numbers on analysis and may be regarded as fairly pure. It therefore appears that. the carboxyl like the nitro-group, whilst raising the rotation of the active group in the ortho-position, has little or no effect in the para-position. [MY:‘. I thalato ................. . ...... -250 o-Nitromenthyl benzoate . . . - 3 8 1 O p-Nitromenthyl henzoate . . . - 237’ Ment8hyl hydrogen phthalate -332 Menthyl hydrogen tcreph-Its rotation was [MI - 259.2O. [M];o. Menthyl benzoate [MI”,” - 239”.It is somewhat’ remarkable that) whilst the free carboxyl group in the para-position differs little in its effect from that of the ester groups in the same position both carboxyl and ester group give a higher value than the unsubstituted menthyl benzoate or its pnitro-derivative. The following table gives the parallel series of esters of phthalic and terephthalic acid molecular rotations, [MI;’ (lzvo) being given in round figures within the hexagon (Mn = menthyl) . Phthalic esters. Terephthdic esters. C0,Mn (A (& \/ C0,Mn C0,Mn \/ C0,P POSITION ISOMERISM TO OPTICAL ACTIVITY. PART XI. 69 Phthalic esters. Tercphthnlic cstors. CO.,Mn \/ C 0 2 isoButyl \/ CO Butyl ,'\ c 0,Mn '236b02 Hexyl v CO.,Mn \/ CO. cycZoHexy1 a/ CO Octyl I n addition to those points to which attention has been directed, i t will be further observed that whilst the rotation of the menthyl alkyl esters of phthalic acid decrease steadily to the isoamyl com-pound and then rise so that the two end melmbers have the highest rotations the opposite effect is seen in the case of the terephthalic esters the two end members possessing the lowest rotations.Further the molecular rotation of menthyl terephthalate is much higher than that of the corresponding phthalic ester and about double that of the acid menthyl terephthalate. If the van't Hoff theory of optical superposition held and assuming that the two menthyl ester groups in dimenthyl tere-phthalate to be so far separated as not to influence one another's rotations the half value ( - 2 6 3 O ) should correspond approximately with that of inenthyl benzoate ( - 2 3 9 O ) .Unless the hydrogen atom in the para-position lowers tThe rotation which does not seem very probable i t would appear that' the ester groups in dimenthyl terephthalate influence one another to the extent of raising the rotation about 1 2 O whilst the average increase for the other members is 1 5 O . Turning now to the nitro-derivatives itl has been already pointed out that the proximity of the nitro-group to the menthyl ester group greatly increases the rotation whilst that in the meta- and ortho-position does not. Much the same result has been observed in the two series of menthyl alkyl nitroterephthalstes 60 COHEN AND DE PENNINGTON THE RELATION OF 0-Nitro m-Nitro o-Nitro 0-alkyl p-alkyl menthyl p-alkyl menthyl menthyl phthalate.terephthalate. terephthalate. C02Mn NO2 /\C09Mn - LA yYCO;*CH \/NO2 C02*CH, 42 It will be seen from the above table that the proximity o€ the nitro-group to the active group raises the rotation being of the same order although rather lower than that of menthyl o-nitro-benzoate ([MI- 381O) and the corresponding nitrophthalates ([MI -343O mean). Here again the curious anomaly is observ-abl0 that whereas in the nitrophthalic esters the rotation falls with the larger alkyl group the reverse occurs with the corresponding nitroterephthalic esters. On the other hand the nitro-group in the meta-position with respect t o the active group reduces the average value ([MI - 2 4 7 O ) to the order of the un-nitrated ester ([MI - 2 5 4 O ) that is to say produces little or no effect.Another curious anomaly to which attention must be directed i s the enhanced rotation of the nitromenthyl esters in benzene solution. [MI3 In the fused-state POSITION ISOMERISM TO OPTICAL ACTIVITY. PART XI. 61 The difference might be ascribed to association but a determina-tion of the molecular weight of dimenthyl nitroterephthalate (which in benzene has a rotation of [MI -781O) by the cryoscopic method in benzene gave a normal result: 0.0851 in 8.79 benzene gave At= -0-1O. We are at a loss to account for these abnormal rotations in solu-tion. It suggested however a possible explanation of the high values of the m-nitro o-alkyl menthyl phthalates all of which being solid a t the ordinary temperature were examined in benzene solutions (loc.cit. p. 225); but a comparison of the rotation of m-nitro o-methyl menthyl phthalate with that of the homogeneous liquid a t looo showed that the solventt had practically no effect. The numbers are: [M]zo in benzene. [M]koO fused. The following is a brief summary of the results : (1) The mutual effect of two menthyl ester groups in the para-position is considerably greater than that of the same groups in the ortho-position. M.W.=483. C,,H,,O,N requlres M.W. = 487. - 446" - 430" (2) This is true t o a less extent of the alkyl ester group. (3) The carboxyl group in the para-position has much the same effect as the alkyl ester groups. (4) Ths nitro-group in the ortho-position with respect to the active group raises the rotation by about looo; that in the m&a-position has little effect.(5) The esters with the nitregroup in the ortho-position with respect to the active group exhibit enhanced rotation in benzene solut'ion. There appears no reason therefore to modify the generalisation defined in the former paper (T. 1914 105 lS95) namely that the element or group lying nearest t o the active group produces the greatest effect. EXPERIMENTAL. The Memthgl Alkyl Esters of l'erephthalic Acid. The method employed in the preparation of these esters may be illustrated in the case of menthyl ethyl terephthalate. In a small distilling flask fitted with an air condenser was placed a mixture of 12 grams of dry powdered t'erephthalic acid and 30 grams of phosphorus pentachloride.The substances were well mixed and warmed gently until the reaction began being after 62 COHEN AND DE PENNINGTON THE RELATION O F wards heated on txhe water-bath until solution was obtained. The phosphoryl chloride was removed by distillation on the water-bath under diminished pressure in a current of dry air. The residue was extracted with benzene and filtered to separate excess of phosphorus pentachloride which is not dissolred. The solvent was removed by heating on the water-bath and finally under diminished pressure. The yield of acid chloride was 22 grams. To the acid chloride 20 grams (twice the theoretical amount) of absolute ethyl alcohol was added and cooled until the first reaction had moderated when the mixture was heated on the water-bath f o r half an hour.The content8 of the flask were then dissolved in ether and the ethereal solution shaken up with small quantities of dilute sodium carbonate solution to remove any free acid after which it was dehydrated over anhydrous sodium sulphate and distilled first at the ordinary pressure to remove ether and then under diminished pressure. ThO yield of diethyl terephthalate was 11 grams (b. p. 14S0/2 mm.; m. p. 36-4OO). It was then half hydrolysed as follows A mixture of 11 grams of the diethyl ester in 14 C.C. of ethyl alcohol and 3 grams of potassium hydroxide in 3 C.C. of water and 14 C.C. of ethyl alcohol was well shaken when the contents solidified. After heating for half an hour on the water-bath a little water was added and the unchanged diethyl ester separated by extracting with small quanti-ties of ether.After removing any residual ether by heating the solution was cooled and acidified with hydrochloric acid. The solid which separated was collected and crystallised from benzene, in which terephthalic acid is very sparingly soluble. I n this way 4 grams of pure acid ethyl est'er melting at 168-170° were obtained. The ester wag heated with a large excess of thionyl chloride (8 grams) under reflux on the water-bath until dissolved any insoluble impurity being removed by filtration. The excess of thionyl chloride was distilled on the water-bath under diminished pressure and the residue (4 grams) which crystallised on cooling melted a t 27O. The calculated quantity of meathol (3 grams) was added and the whole heated gradually in an oil-bath tlo 110-120° for an hour or mdre until the evolution of hydrogen chloride ceased.The excess of menthol was then removed by distillation in a current of steam and the residue extracted with ether. The ethereal solution after shaking with sodium carbonate solution was dehydrat'ed over calcium chloride and decolorised with charcoal and then distilled first on the water-bath and then with the flame and under diminished pressure. The excess of alcohol used in the preparation of esters of th POSITION ISOMERISM TO OPTICAL ACTIVITY. PART XI. 63 higher alcohols was removed by distillation under diminished pressure. The following table gives the melting and boiling points of the dialkyl esters and the alkyl acid esters.Dialkyl terephthalate. Dimethyl ......... Diethyl ............ Dipropyl.. .......... Di-rt-butyl ......... Diisobutyl ......... Dicyclohexyl ...... Dioctyl ............ M. p. B. p. 140° -36-40 142/2 mm. Liquid 158/4 mm. Liquid 18014 mm. 40-43 lS0/6 mm. 75-80 -- decomposed Alkyl hydrogen terephthalete. Methyl hydrogen Ethyl Y 9 Butyl 9 9 isoButyl ,, cycloHexy1 ,, Propyl 9 7 Octyl f Y M. p. About 230° Indefinite. i 6 a - 1 7 0 127-1 2 9 122-124 151-154 160-162 82- 54 The menthyl alkyl esters obtained by the method described above are viscid liquids with a faint yellow colour which could not be removed by charcoal. The rotations were determined with the pure substances in a 0-302-dcm.tube at 20° and looo. Alkyl menthyl terephthdate. Methyl ......... Ethyl I ......... .. I1 ...... Propyl ......... n-Butyl ......... isoButyl ...... c ycZoHexyl I . . , I1 ... Octyl I ......... , I1 ......... a?. Die. [ol]y. [M]y. 24-66 1.054 77.49 246.3 24.45 1.060 76.38 253.6 24-42 1.050 77.45 257-0 23.20 1.041 73.79 255.4 22.39 1-037 71.48 257.3 23.30 1.044 73.91 266.1 20.90 1.034 67.06 258.9 21.42 1-038 65-33 263-7 17.84 0.999 59.13 246.0 17.91 0.999 59-36 246.9 a r . D:""". [ a ] r . [MI:''. 23.11 1.000 76.52 243-3 21.78 0.998 72-28 240.0 21-76 0.991 72.58 240.9 20.72 0.9845 69-69 241.2 19.90 0.9848 66-91 240.9 20.86 0.988 69.92 238.2 18.63 1.009 61-14 236.0 19.09 1.004 62.92 242.9 15.96 0.947 55.82 232.2 16.03 0.945 56.16 233.6 The following are the analytical results: Found.Calculated. Alkyl menthyl 7- c ester. Formula. Carbon. Hydrogen. Carbon. Hydrogen. Methyl menthyl Cl,H,,O 71-60 8-20 71.69 8-18 Ethyl menthyl ... C,,H,,O 72-16 8.4 8 72.30 5-44 thyl ............ C,,H,,O 74.66 8.78 74-68 8-81 Octyl menthyl ... C,,H,,O 74.99 9.66 75.01 9.62 cycloHexy1 men-Neutral and Acid Menthtyl Esters of Terephthalic Acid. The neutral ester was obtained in the usual way from the acid chloride the excess of menthol being subsequently removed by steam distillation. It crystallised from hot alcohol in needle-shaped crystals melting at! 77-78O. I. 0.5208 in 25 C.C. benzene in a 2-dcm. tabe a t 13O gave 01 -4-91 ; hence [a? - 117.9; [MJ; - 521.1 64 COHEN AND DE PENNINQTON THE RELATION OP A t looo in a 0-302-dcm.tube; DlOO 0.979. 11. 0-5210 in 25 C.C. benzene in a 2-dcm. tube at 12.5* gave At looo in a 0-302-dcm. tube; Dlo0 0.978. 0.1830 gave 0*5100 CO and 0.1569 H20. The acid estler was prepared by the semi-hydrolysis of the neutral ester as follows An alcoholic solution containing 1.3 grams of potassium hydroxide was added to 10 grams of dimenthyl t e r e phthalate and the mixture heated on the' water-bath for two hours. The product was poured into water and the unchanged neutral ester and menthol extracted with ether. Aftler removing the ether hydrochloric acid was carefully added to the slightly warm solution when an oil separated which was dissolved in a small quant'ity of benzene (in which terephthalic acid dissolves sparingly).The benzene solution was dehydrated with anhydrous sodium sulphate and the benzene removed first on the water-bath and finally under diminished pressure. The residue consisted of a colourless resin-like substance which did not crystallise : C,,H,,O requires C = 71-06 ; H = 7.89 per cent. a:' - 30.22 ; [a]:,"' - 102.3 j [MI:' -_ 451.7. a - 4.96 ; hence [a]:;'5 - 119 ; - 525.9. a::' - 30.3 ; [a]:@ - 102.6 ; - 453.5. C=76*00; H=9.53. C,H,,O requirw C = 76.02 ; H = 9.50 per cent. 0,1805 gave 0.4723 CO and 0.1265 H20. 0.5160 in 25 C.C. benzene in a 2-dcin. tube gave ub' -3-52; hence C=71.33; H=7*78. [a]:" 85.11 ; [MI'," 259.2. Neutral and Acid Menthyl Esters of Nitroterephthalic Acid. The nitroterephthalic acid was prepared by the method described by Burkhardt (Ber.1877 10 145). The dimenthyl ester was obtained in the usual way by treating the acid chloride (formed by the acttion of phosphorus pentachloride on the acid) with the calculated amount of menthol and purifying in the manner already described. After recrystallisation from alcohol it was obtained iu colourless needles melting a t 8 8 O : 0.1532 gave 0.3873 CO and 0.1168 H20. G.5084 in 25 C.C. benzene in a 2-dcm. tube gave a'," -6-53; hence At iOOo in a 0.302-dcm. tube the pure ester gave a'," -36.26. The acid ester was prepared by the semi-hydrolysis of the neutral C=68.93; H=8*47. C,H,,O,N requires C = 68.98 ; H = 8-42 per cent. Calk5 - 160.5 ; [MI - 7131.2. [a)p - 116.0 ; [MI;' - 564.8 POSITION ISOMERISM TO OPTICAL ACTIVITY.PART XI. 65 ester with the calculated quantity of potassium hydroxide in Illethyl alcohol i n {,he manner already described irl the previous section. After twioving uiichanged neutral ester the acid ester was precipiilatetl by the careful addition of coiicentrated hydro-chloric acid. The solid acid ester was collected and cryst>allised from aqueous alcohol when i t melted at' 7 5 O : 0.1550 gqve 0.3515 CO and 0.0924 H,O. A second preparation gave the same result. On reconverting the acid ester into the dimenthyl ester by treat-ing with excess of thioiiyl chloride and heating the resulting acid chloride with menthol t'he product had the same rotation as that found foz. the ester obtained by the previous method of preparation. C-61.84; H=G*62.C,,H,,O,N requires C = 61.9 ; H = 6-59 per cent. o-Nifro p-A 1ky1 5?wephthn7ic Esteys. The esters were prepared as follows The acid menthyl ester was heated with excess of thionyl chloride on the water-bath until a clear solution was obtained the excess being removed under diminished pressure. The acid chloride was then heated under reflux with an excess of alcohol on the water-bat'h for about ail hour until the reaction was complete. The product was poured into water the ethereal extract being shaken with small quantities OF dilute sodium carbonate solution and dehydrated over calcium chloride with the addition of animal charcoal. After removing the ether the nitroalkyl menthyl esters were obtained as viscid liquids with the exception of the methyl ester which crystallised in needle-shaped crystals melting a t 78-79O.The rotations were determined in the fused state in a 0.302-dcn1. tube ah 20° and looo and also in benzene solution in a 2-dcm. tube. I n the fused state. ----- o-Nitro p-alkyl menthyl terepht(ha1nte. . a:. DT. [u]:. [MK. Methyl - - - -Propyl I ............... 31.09 1.110 92.74 352.6 .. 11 ............... 31-20 1.126 931.77 358.8 .. IT ............... 30.04 1.090 90.51 306.8 .................. Ethyl .................. - 31-66 1.410 -91.58 -345.2 n-Rutyl 1 ............... 29.64 1.098 90.48 366.5 In the fused state. o-Nitro p-alkyl menthyl terephthd a h Methyl .................. -Ethyl .................. , II ............... n-Rutyl I ............... ,) T I ...............Propyl J ............... VOL. CX-CLII. /-- a~~~ .30*5(3 28.53 27.79 27.92 26.57 26-62 I)' DYo. [u]:'. 1.093 -92.41 1.08 85-45 1.056 87-22 1.063 87-02 1,043 84.33 1 040 84.74 [M$O.' - 335.5 322.2 341-0 340.2 341.6 343.3 66 RELATION OF POSITION ISO'bIERISN TO OPTICAL ACTTVITY. o-Nitro p-alkyl , terephthalats. benzene. menthyl Gram in 25 cue. Methyl I ............ 0.4990 Ethyl .................. 0.5100 Butyl .................. 0.5052 .. I1 ............ 0.3665 Propyl ............... 0.6032 In benzene solution. /L -a:. [a]'dp. [M]:. -5.65 -141*4 613.0 4.16 141.7 515.0 5.45 130.5 491.8 6.2 1 149.7 507.2 504 124.7 505.2 On analysis the following results were obtained : Alkyl menthyl [-A'---- \ 7-\ Found.clalcul at sd. ester. Formula. Carbon. Hydrogen. Chrbon. Hydrogen. Met'hyl ............ CI9H2,O6N 62-82 6.86 62.8 1 6*8!) Ethyl ............... C2,,H,,O6N 6:3*40 7.20 63*6(i 7.16 Rutyl ............... C,,H,,O,N 65-11 7.70 05.1s 7.G5 m-Nitro p-Alkyl Menthyll Terephth'alic Esters. The esters were obtained by the semi-hydrolysis of the neutral alkyl estaers. The acid alkyl ester thus obtained was converted into the acid chloride which was then heated with menthol and purified in the usual way. The following table gives the melting and boiling points of the dialkyl and m-nitro pa2kyl esters all of which were crystallised from benzene. m-Nitro p-dkyl ?%-Nitro p-alkyl M. p. M. p. menthyl ester. acid ester. Methyl ............ 72-74" 1 7 6 - 1 76" Ethyl ............... 48 146-1 48 Propyl ............ R. p. 192/6 mm. 135-137 Butyl ............... B. p. 21 5,/6 nini. 132-334 The rotations were determined in the fused state in a 0.302-dcm. tube a t 20° and looo. m - Ni tro p - alkylmen -thyl ester. a:. Die. [a]:. [MI:. a:'. Dio0. [a]:'. [M]go. Methyl .................. 23.38 1.133 68.31 248.0 20.58 1,096 62.19 -Ethyl I ............... 22.31 1.127 65.55 247.1 19.55 1.074 60.67 -, I1 ............... 22-29 1.130 65.31 246.2 19.48 1.074 60.06 -Propyl .................. 21-25 1.130 62.25 248.4 18.50 1.000 58.73 -Butyl .................. 20.60 1.136 60.23 244.0 18.36 1.057 57.53 -The following results were obtained on analysis : Found. Calculated. Nitro alkyl men- v---\ ,---Butyl ............... C22H310SN 65-21 7-60 65-18 7-85 thyl ester. Formula. Carbon. Hydrogen. Carbon. Hydrogen. Ethyl ............... C,&t,,OoN 63-60 7.20 63.66 7.16 THE UNIVERSITY, LEEDS. [Received December 12th 191'7.

ISSN:0368-1645    

DOI:10.1039/CT9181300057

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

NITRO-DERTVATTVFIS O F ISO-OXAJ)IAXOT,l? OXTDXS ETC'. 67 By ARTHUR G. GREEN and FREDERICK MAURICE ROWE. IN a pre'vious communication (T. 1913 103 2025) we have directed attention to tha so-called " nitro-o-dinitrosobeiizene and tlinitro-o-dinitrosobenzene " obtained by Drost (A47zi~rrZeii 1899, 307 54) by the nitratjon of benzisoox:Ldi;txole oxide (then termed o- (1 i 11 i t r osobeiizeii e) . The diiiitro-coin~~ou~i~l (I) is of special interest, hecause i t NO N N N possesses acidic properties reacting for example with potassium hydrogen carbonat,e to form the potassium salt C,HN,0,K,*-H20 (Drost). Zincke and Schwarz (Annulen 1899 307 32) consider that' the metal in this potassium salt is probably directly attached to carbon and that it is the hydrogen atom between t,he two nitro-groups which is replaced for the isomeric diiiitro-compound (11) possesses no acidic properties, As an alternative Zincke and Schwarz suggest the possibility that the salt may be a derivabive of the isomeric compound, NO NO which is reconverted into the original oxadiazole oxide on treating the salt with acid.The latter hypothesis does not appear to us to afford a satisfactory explanation in view of tke improbability that oxygen should wander with such facility from the nitro-group to the carbon nucleus and back again merely under the influence of weak alkalis or acids. I f the acidic properties are t o be ex-plained by the presenoe of a hydroxyl group it' would seem more probable that the latter is formed in the nitration of the benziso-0 68 GREEN AND ROWE NITRO-DERIVATIVES oxadiazole oxide the product of which might' possibly hydrorr~beiizisooxa~~iazole, rather than dinitrobenzisooxadiazole oxide'.I n order to test this possibility the pure compound OF be a dinitrn-was reduced with titanous chloride. If a hydroxyl group is present 18 atoms of hydrogen will be required for complete reduction whereas i f there is no hydroxyl group present 20 atoms of hydrogen will be needed. Experiment showed that 20 atoms of hydrogen are required, thus proving the coinpouiid t o be a true dinitrobenzisooxadiazole oxide. We are therefore reduced t o the conclusion that we have here in fact an example of hydrogen in the benzene ring possessed of acidic properties. An attempt was made t o obtain a hyclrosy-derivative of benz-isooxadiazole oxide by the oxidation of i~it~o-~~~amiiiophe~iol, /-\ NO2 with sodium hypochlorite with the object of preparing its nitro-derivatives.Itl was found however that oxidation of nitro-p-aminophenol under all conditions resulted in the disruption of the ring accompanied by the formation of chloropicrin and nothing else conld be isolated. The hydroxyl group must therefore be added to the list of substituents already given (T. 1917 111, 613) which when occupying the para-position with respect to the amino-group in a substituted o-nitroarnine render the ring unstable t o oxidation with hypochlorite. In view of ths interest attaching t o dinit'robenzisooxadiazole oxide i t appeared desirable to investigate also the dinitro-deriv-ntive o f benzisooxadiazole of which only the mononitro-derivative, has been prepared by Drost (A~zlzccZe/2 1899 307 69).All our attempts t o prepare a dinitro-derivative however failed whether benzisooxadiazole or nitrobenzisooxadiazole was employed and whether nitration was effected in the cold or at higher temperatures, with one or with more than one molecular proportion of nitric acid ISO-OXADIAZOLE OXIDES AND OF ISO-OXADIAZOLES. 69 Finally we have prepared and examined the previously unknown nitro-derivatives of naphtbisooxadiazole oxide and of naphthiso-oxadiazole itself. Nitration of naphthisooxadiazole oxide in sul-pliuric acid solution with three four or five molecular proportions of nitric acid either in the cold or a t 50° gave rise t o a single product.On diminishing the quantity of nitric acid to two one and a-half or one molecular proportion the same product was also obtained although in admixture with unaltered naphthiso-oxadiazole oxide. It crystallises in yellow needles melting at 2 1 5 O , and on analysis with titanous chloride proved to be a dinitro-compound. No trace of a mononitro-compound was obtainable. The dinitronaphthisooxadiazole oxide is very resistant to oxida-tion but 3-nitrophthalic acid in sufficient' amount for identification was obtained by prolonged boiling with chromic acid and acetic acid This proves that a nitro-group is situated in each ring one being in position 5 or 8 and the other in probably the substance has the constitution N,-O pcsition 4 or 3.Most Owirig to the destructive decoinpositioii exerted by dilute alkalis, i t was not found possible t o coiivert the compound into the corre-sponding dinitronaphthaquinonedioxinie or diiiitroiiaphtlliso-oxadiazole. Naphthisooxadiazole cliff ers coiisiderabi y from naphthisooxadi-R Z O ~ oxide iii its behaviour 011 nitration. When nitrated iii sulphuric acid solution with oiie and a-half inolecular proportioils of nitric acid it is coiiipletely coiiverted into a product which crystallises in needle? nieltiiig a t 1 4 3 O . Analysis by titanous chloride showed this product to be a iiioiionitronaphthisooxadiazole. Oxidatioii with chromic acid and acetic acid produced 3-nitro-phthalic acid showing that the nitro-group is in position 5 or 8. The compouiid most probably has the constitution N- 0 I \ It differs from the nitro-derivatives which 'follow in that it is When the iiot affected by alkalis and does not react witlh aniline 70 GREEN AND ROWE NITRO-DERIVATIVES OF quantity of nitric acid is increased to 3 4 or 5 or even 10 mole-cular proportions a mixture of two compounds is always obtained, the separation of which may be readily effected by means of alcohol.The amount of the more readily soluble product decreases with increase of the quantity of nitric acid used and with 10 mole-cular proportions of nitric acid it is only formed in traces. It xrystallises in yellow leaflets melting a,t 1 4 7 O . The less readily soluble portion which constitutes the main product of reaction, cryst’allises in long yellow needles melting a t 1 9 6 O .On analysis with titanous chloride t’he former product prove1 t o be a inoiio-iiitronaphthisooxadiazole the latter a dinitroisooxadiazole. Oxida-tion of the dinitro-compound produced 3-nitrophthalic acid whilst from the mononitro-compound phthalic acid was obtained. Hence the nitro-groups are in positioiis 6 or 8 and 4 or 3 in the dinitro-compound and in positions Their constit’ution may most 4 or 3 in the mononitro-compound. probably be represented thus : The rnonoiiilro-conipouiicll N-0 I \ I cliff ers f roiii the previously described isomeride in reacting with alkalis and with aniline. I n this respect it is similar t o the dinitro-compound. It appears therefore that reactivity with alkalis and with aniline is conditioned by the presence of a nitro-group in the same ring as the furazan group.On further nitration both mononitro-derivatives give rise to the above dinitro-compound, E X I’ E 1t I M 1.; N T A L. 3 5-l)itLil)’o?t~tl~iSooJ’tidic(so7e Oside (Ili,iilt.ol,citsftrl.o,r.trlr) (1). Tliis was prepared as described by Drost (A?l?w~7e?t 1899 307, 54) by the nitration of henzisooxadiazole oxide in sulphuric acid solution. It crystallised from acetic acid in large yellow needles melting a t 1 7 2 O . Tit ra t io 12. zu it k Ti t 11 72. o u s Gh lo i.icle .-0 a 0 1 required 2 9 8 c . c . TiCl (1 C.C. =0*001655 grains Fe). Calculated as C?,H2(NO),(N0,) == 9‘3.5 l)t!r ~ c i i t . t l i a t is 2OH required for reciuctioil ISO-OXADIAZOLE OXIDES AND OF ISO-OXADIAZOLES. 71 4(or 3) 5(or $ ) - n i i ~ ~ t r o n a p h t ? ~ i s o o ~ a ~ i a ~ ~ l e Oxide (Diiiitronaph tha-furoxam) prob a b 1 y N-0 \ I 0,: /\/\-AN '\ \/ I ) I NO NO, Ten granis of naphthisooxadiazole oxide (T.1917 111 616) dissolved in 100 C.C. of concentrated sulphuric acid were nitrated by the addition of a mixture of 9 C.C. of nitric acid (95 per cent.) and 30 C.C. of concentrated sulphuric acid. The mixture was cooled a t first and then warmed to 50° and poured 011 ice. The product, when crystallised from glacial acetic acid or nitric acid formed bunches of small prismatic needles melting at 2 1 5 O . Titration with Titnnous ChZoride.-O*0105 required 23.6 C.C. TiCl (1 c.c.=0*001801 gram Fe). Calculated as C1,H4(NO),(N0.J2 = 99.7 per cent. that is 20H required for reduction.0'131 gave 22.5 N at 1 6 O and 762 mni. C,,H4O,N4 requires N = 20.29 per cent'. Diiii t r onap h t hiso oxa di azole oxide when t r e a t'ed with pot assiurri hydrogen carbonate in the manner described by Drost for the pre-paration of the potassium salt of diiiitrobenzisooxadiazole oxide, does nott form a salt. It is however sensitive to alkalis and dis-solves with deconiposition in boiling sodium carbonate or dilute sodium hydroxide solution giving a reddish-bro-xn solution with the evolution of ammonia and formation of nitrite. If however, a little dilute sodium hydroxide is added t o an aqueous suspension of the finely divided substance and the mixture cautiously warmed to 30-40° solution occurs and after some time a red precipitate separates.This product which is apparently a salt crystallises from water in fine red leaflets. On geiitly warming the dry pro-duct it decomposes with slight detonation. On acidifying its aqueous solution a reddish-brown precipitate of impure dinitro-naphthisooxadiazole oxide is obtained. When warmed with aniline dinitronaphthisooxadiazole oxide behaves in an analogous niaiiner to diiiitrobenzisooxadiazole oxide. Itt 'dissolves with a red colour and 011 the addition of alcohol ail aiiilide separates in reddish-brown needles which melt and decompose at 1 6 6 O . This aiiilide is soluble in alkalis with a red colour showing that. reduc-tion t o the dioxime takes place siiiiultaiieously with the introcluc-tioii of aiiiliiic into tllo nucleus. N=20*14 72 GREEN AND ROWE NITRO-DERIVATIVES O F In endeavouring to ascertain the position of the nitro-groups in dinitronaphthisooxadiazole oxide various methods of oxidahion were tried.The subst'ance is not4 affected by boiling with dilute or fuming nitric acid and only by prolonged boiling with chromic and acetic acids was a small quant'ity of 3-nitrophthalic acid obtained. 'This crystallised in yellow prisms melting at' 2 1 8 O and gave the anhydride melting a t 1 6 3 O . 5 (0 r 8) - il'i t ronaph t h is o o xcidia z o I e (Nitro 71 a ph t hu f ura a a tz.), N -0 A solutioii of 10 grains of naphthisooxadiazole in 100 C.C. of conoentrated sulphuric acid was nitrated in the cold by adding a mixture of 3.6 C.C. of nitric acid (95 per cent.) and 15 C.C. of concentrated sulphuric acid.The product crystallised from nitric acid in almost colourless silky needles melting a t 143O. It is not affected by boiling with aqueous alkalis or alkaline sodium h y p -chlorite. Titration with Titurbous Chlol.z'de.-0.0112 required 20.4 C.U. TiCl (1 C.C. -0*001708 gram Fe). Calculated as C,,H,(N,O)-NO,= 99.6 per cent. that is 1211 required for reduction. Prolonged boiling with chroiiiic and acetic acids converted this iiitronaphthisooxadiazols into 3-iiitrophthalic acid iuelting a t 21W, and forming the anhydride liieltiiig at 1 6 P . It does riot react with aniline. A aolutioii of 10 grams of iiaphthisuoxadiazolG iii 100 C . C . OI concentrated sulphuric acid was treated with a mixture of 9.5 C.C. of nitric acid (95 per cent.) and 25 C.C.of coriceiitrated sulphuric, acid. The mixture was cooled at first and then warmed to 40". The product crystallised from alcohol iii 10119 yellow iieedlcs niclt-iiig a t 1 9 6 O ISO-OXADIAZOLE OXIDES AND O F ISO-OXADIAZOLES. 73 The same substance is obtained by further nitration of either of the two iiiononitronaphthisooxadiazoles. Titration ulitk Tifano?is C I h 7 n ~ i d ~ . 0.01 i*eqiiirprd 22.5 c c. TiC1, (1 c.c.=0*001712 gram Fe). Calculated as C,,H,(N20)(N02) I= 99.12. per cell t . t h a t is 18H required for reduction. DinitroiznplL thisooxndkzole dissolves in boiling dilute alkalis with decomposition. On the addition of a few drops of sodium hydroxide to a finely divided aqueous suspension and gently warm-ing a yellowish-brown solution is obtained from which a brown, flocculent precipitate separates on keeping.This precipitate when decomposed by acids does not yield unaltered dinitronaphthiso-oxadiazole. I)iiiitroiiaphthisooxadiaxole' dissolves i t 1 aniline 011 warming with a reddish-brown colour. On the addition of alcohol, an anilide separates in long reddish-brown needles melting at 9 8 O and soluble in alkalis. Prolonged boiling with chromic and acetic acids converts the dinitronaphthisooxadiazole into 3-nitrophthalic acid melting a t 2 1 8 O and forming the anhydride melting a t 1 6 3 O . 4 (or 3 ) -iVi nrtpli f 12 i so0 xn tliaa ole (Nit 1'0 t i nPpk t h u f u i~ccza I?,) , y _ _ _ -0 A \ /\/\ ' '\I ' I I I-* \/\/ NO2 On concentrating the mother liquors from which dinitronaphth-isooxadiazolel has separatled a second crop of crystals is obtained.After twice recrystallising from alcohol the product forms yellow leaflet2 melting atl 1 4 7 O . No method was found by which naphth-isooxadiazole could be completely converted into this compound. Titration with Titanous Chloi~ide.-0+0102 required 17.7 C.C. TiC1 (1 c.c.=0*001801 gram Fe). Calculated as C,,H,(N20)*N0 = 99.9 per cent. that is 12H required for reduction. 4-Nitronaphthisooxadiazole dissolves in boiling dilute alkalis with decomposition. On the addition of a few drops of sodium hydr-oxide to a finely divided aqueous suspension of the compound and gently warming it dissolves with an orange-red colour and a brown flocculent precipitate separates on keeping. This pre-cipitate is decomposed by acids but does not yield unaltered nitro-naphthisooxadiazole. Nitronaphthisooxadiazole dissolves in aniline on warming with a reddish-brown colour. On the addition of alcohol an anilide crystallising in red needles melting a t 9 4 O and D 74 I-IOLMES; THE MERCURY AMMONTA COMPOUNDS. PART I. soluble in alkali3 is obtaiiied. Prolonged boiling with chromic and acet,ic acids converts thiv nitronaphthisooxadiazole in to pht.halic scitl from wliicli tlie anhyclride ~nelting a t 138" is obtained. I n conclusion we desire t o express our thanks t o Miss Eva Hibbert who has kindly carried o u t the titrations of these nitro-compounds with titanous chloride. DPESTUFF RESEARCH LABORATORY, MtrNICrPAL SCHOOL OF TECHNOLOGY, MA NCHERTE R. [ Receiw? Ikcenther 1 %I) 1917.

ISSN:0368-1645    

DOI:10.1039/CT9181300067

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

74 I-IOLMES THE MERCURY AMMONTA COMPOUNDS. PART I. By MURIEL CATHERINE CANNING HOLMES. A LARGE number of solid products of the action of aqueous and dry ammonia on mercury salts either in the presence or absence of the corresponding malts of ammonium have been described as distinct chemical compounds but as the solids are in some cases non-crystalline precipitates and the only evidence of their being chemical compounds is the approximate correspondence of the analyses with simpler chemical formulz it! is not improbable that some of these so-called compounds are solid solutions the composi-tions of which vary with the conditions of precipitation or even mixtures of two distinct phases. Franklin (Amer. Chenz. J. 1912, 47 361. See also J . Amer. Chem SOC. 1905 27 835; 1907 29, 35; and Zeitsch.anorg. Chem. 1905 46 l) in an excellent summary of the extensive literature on this group of compounds, has emphasised the1 worthlessness of the evidence on which some of the products oh tained have been characterised as chemical individuals. Four modern investigations of Gaudechon ( A ~ H . Chim. Phys. 1911 [viii] 22 145) Striirnholm (Zeitsch. aizorg. Gheent. 1908 57 72) Widman (Zeitsch. afiorg. Chem. 1910, 68 I) and Frangois (Compt. reid. 1900 130 332 1022) to which reference will have to be made later have however furnished results which were shown to be consistentl with the phase rule and in certlain cases with the masa law. The mercuriammonium compounds can be grouped under the three following classes : I. The additive compounds of mercury salts and ammonia of which fusible precipitate HgC1,,2NH3 is the best.known example I-IOLMES THE MERCURY AMMONIA COMPOUNDS. PART I. 75 11. The ariimonolysed 'k conipounds in which m e or other of the ammonia resicluefi NH, NH or N take the place of acid radicles i n a inercury salt. infusible prtvipitatp C'lHgNH', i 5 the .;irnple$t representative of this class. 111. The compounds which are both liydrolysetl ant1 animono-lysed. For example the chloride of Millon's base or HO*Hg*NH*HgCI. It should' here be mentioned that Rarnmelsberg (J. pi'. Chenz., 1888 [ii] 38 563) Pesci (Gnzzettn 1889 19 509; 1890 20 485), arid Gauclechon (Zoc. cit.) advocate the formulation of all three classes of substances as molecular compounds of climercuri-ammonium ClHHg,N with different molecular proportions of water, ammonia ammonium salts and mercuric salts.However Hof-mann and Marburg (AnnuZen 1899 30.5 191; Zeitsch. m o r g . Chenz. 1899 23 126) and Franklin (Zoc. cit.) have pointed out thatl this unusual method of formulation cannot be adopted in the case of the mercury alkyl- and aryl-amines although these must in the absence of any evidence to the contrary be regarded as constituted similarly t o the corresponding mercuriammonium compounds. Furthermore the same authors have shown in t'he opinion of the writer convincingly thatl Rammelsberg's dimercuri-ammonium theory is supported neither by analogy nor by any single' fact which cannot be as satisfactorily explained by the older and more natural view of the structure of these substances.H,N Hg*O*HgCl T?be Additive Compouiids o j ill'ercuvic Chloride and Ammonia. Mercuric chloride unites with twelve molecular proportions of ammonia when i t is treated with liquid ammonia and a t the same time ammonolysis takes place in accordance with the equation (Franklin loc. c i t . ) HgCl,,lZNH,= ClHgNH + NH,Cl+ lONH,. The ammonium chloride produced dissolves in the liquid ammonia. It is probable that the change is reversible and that in the presence of a saturated solution of ammonium chloride in liquid ammonia the ammine would be stable. By the action of gaseous ammonia on mercuric chloride fusible precipitate HgC1,,2NH, is formed; but this compound can he obtained as well-defined crystals by dissolving infusible precipitate or the chloride of Millon's base in a hot saturated solution of ammonium chloride a i d cooling the filtered solution.I n this * The term ammonolyse was introduced hy Franklin. Its meaning correspoiids with that of hydrolysc. D" 76 ILOLMES TIXE MERCURY AMMONIA COMPOUNDS. PART I. case it has been shown by Gandechon ( l o r . c i t . ) that the actioss are reversible in accortiance with ithe equations C’JHg*O*HgNB -+ NH,C11 zf %OlHgNI’I,-i- H,O, ClHTgNH -1- NH,Cl I=; BgC1,,3NI€,. The product’ obtained by Kaiie ( A ?ill. Chim,. I’hys. 1839 [ii], 72 215 337) by heating mercuric chloride in dry ammonia or by volatilising a mixturel of mercuric oxide and ammonium chloride, and supposed by him to be HgCl,,NII, is according to Pesci (Gazxettn 1890 20 485) and Dammer (“ Handbuch der Anorg.Chemiel,” 11 2 803) probably a mixture. I t is therefore unlikely that any compound OF mercuric chloritlc xiid ammonia containing a less proportion of ammonia than fusible precipitate has been prepared. I n order to test if such a sub-stance is capable o€ existence dry ammonia was passed into an ethereal solution of mercuric chloride the current of gas being stopped before all the mercuric chloride had been precipitated. The flocculentl precipitate was washed with ether left in a vacuum desiccator for several hours aiici then analysed.‘K The analysis furnished the following numbers : Found Hg = 69.34 ; C1= 24.30 ; NH3= 5.98. HgCI,,NH requires Hg = 69-52 ; C1= 24.58 ; NH3= 5.89 per cent. This analysis proved thatl a lower ammine of mercuric chloride mustl exist but it did not show thatl thel compound was HgC1,,NH3, and as a matter of factl it will be shown later that the precipitate was almost certainly a mixture.When the ethereal solution of mercuric chloride was saturated * As the mercuriammoniuni compounds lose their ammonia only after prolonged boiling with concentrated alkali and as the chlorine ion cannot be precipitated completely in the presence of a mercuric salt by silver nitrate, a special method of analysis had to be employed. To estimate the mercury and ammonium the salt to be analysed was dissolved in dilute hydrochloric acid tho mercury was precipitated as sulphide with hydrogen sulphide and the precipitate collected dried and weighed in a Gooch crucible. The filtrate and washings were boiled to remove hydrogen sulphide.Sodium hydroxide was then added to the cooled solution and the ammonia distilled off into a standard solution of acid. To estimate the chlorine another weighed portion of the salt was dissolved in dilute sulphuric acid the mercury in the solution precipitated by hydrogen sulphide and the sulphine removed by filtration. The hydrogen sulphide in the filtrate was then removed as completely as possible in a vacuum the small quantity which remained being precipitated with copper sulphate in slight excess. Tho copper sulphide was filtered off and the chlorine deter-mined in the filtrate by precipitation with silver nitrate HOLMES THE MERCURY AMMONIA COISIPOUNDS. PART I. 77 with ammonia the composition of the precipitate was approxirn-ately that of fusible precipit'ate HgC1,,2NH3.An attempt' was next made to prepare the lowest ammine, namely that which is stable in the presence of the solid mercuric chloride( by shaking the finely divided fusible precipitate prepared as above with a saturated ethereal solution of mercuric chloride. The analysis furnished results in agreement with the formula The product must theref ore have been partly ammonolysed during the washing with ether. As the analysis appeared to indicate that i t would be difficult to obtain a pure substance by the above method of preparation, another mode of preparing the substance which it was thought might furnish it in a crystalline form was tried. The experi-ments with ether had demonstrated that the compound it was desired to prepare was stable in the presence of a saturated solu-tion of mercuric chloride in ether.Itl ought therefore to be stable in a saturated aqueous solution of mercuric chloride provided that ammonium chloride in sufficient quantity to prevent ammonolysis is dissolved in the water. From such a solution therefore an attempt' was made to prepare the crystalline ammine. Infusible precipitate was digested at looo with solutions of mercuric chloride of different concentrations in an approximately concentrated solution of ammonium chloride the solution filtered while hotl from the undissolved precipitate and allowed t o cool slowly. Well-defined crystals began t o separate out when the temperature had fallen almost' t o that of the laboratory and gradually increased in aniount for several hours.The crystals were rapidly separated from the mother liquor by means of the pump washed twice with alcohol and twice with ether left in the vacuum desiccator for several hours and then analysed. The results which are recorded in the following table show that a compouiid 3HgC1,,2NH3 undoubtedly exists and that it is improb-able that there is a compound stable at the ordinary temperature, intermediate in composition between this and fusible precipitate, I n the toy row of the table is given t h e composition of the liquid phase in grams of mercuric chloride in 100 grams of water contain-ing about 42 grams of aminonium chloride and in the next three rows are the percentages of mercury ammonia and chlorine in the solid phase.N gCl, 2 N €1, 78 HOLMES THE MERCURY AMMONIA COMPOUNDS. PART I, Per cent. of 130 grams. 130 grams. 130 grams. 120 grams. Hg ............ 70-39 70.92 70.75 70.38 NH3 ......... 4,066 4-022 3.98 4.086 c1 I 26.01 25.01 -Compound ............... separated 3HgC1,,2NH3 3HgCl2,2NH 3HgC12,2NH 3HgC1,,2NH3 Per cont. of 110 grams. 100 grams. 95 grmis. 65 grams, Hg ............ 70.s1 65-46 65-20 64.20 NHJ ......... 3.995 10.70 10.G6 11.48 - - - I c1.. ............. Compound separated 3HgCl2,2NH €IgC‘l,,2NH3 HgC1,,2NH3 HgC1,,2NH3 3HgCl,,2NH3 requires Hg = 70.54 ; NH = 4.0 1 ; C1= 25-15. HgC12,2NH requires Hg=65-67 ; NH,= 11.13; C1=23.13 per cent. Striiinholm claims t o have established the existence of a com-pound of the formula HgCl,,R,NHgCl and Gaudechoii of the com-pound €IgCl,(Hg:N*HgCl) ; but that the work on these compounds needs to be repeated is shown by the following quotation from Franklin’s monograph on the inercuriammoiiium compounds.“ Stromholm was not sure of the existence of a chemi2al in-dividual of the formula Hg,N,Cl,. Gaudechon on the contrary, obtained results pointing sharply t o the formation of this com-pound and asserted his belief that no compounds intermediate in coinposition between Hg,N,C4 and the normal salt exist ; that’ is, Gaudechon does not accept the existence of a compound of the formula NH,HgCl*HgCl,.” I have therefore repeated Striimholm’s work and have obtained results which confirm his conclusions. A dilute solution of aminonium chloride was nearly saturated with mercuric chloride.It was then heated at looo for one or two hours with infusible precipitate filtered and left to cool. The precipitate obtained was in the form of a fine white powder which, after washing and drying was much more loose and bulky than the other mercuriainmoiiium precipitates. When the ammonium chloride was very dilute i t was necessary to employ as much as 2 litres of solution in order to obtain a quantity of precipitate sufficient for analysis. From the more concentrated solutions o l ammonium chloride the precipitate began to be formed a t fairly high temperatures whereas from dilute rolutions it did not’ separate until the temperature of the laboratory was reached. The pre-cipitate was collected washed and nnalysed by the method described above.The composition of the precipitate varied only slightly with the amount. of ammonium chloride in the solution and the temperature a t which it was formed '' SPARK-LENGTHS " IN HYDROCARBON GASES AND VAPOURS. 79 Gram of Percentags comporition and NH,CI in Temperature atomic ratios for solid phase. 100 grams of pracipi- 6 * of water. tation. x. Hg. c1. 11-86] --. 1 50-30" 2.83 75.38 -1 30-15 2.95 74.66 -0.3 30-15 I 75.80 -0.3 30-15 2.76 75.60 -0 . 3 30-15 2.83 75.50 -0.5 30-20 2.78 75.60 20.63 t11 [I1 [ 1.791 111 [1*91] PI [1*87] PI [1*9OJ [2.91] HgCI,,H,NHgCl requires N=2.675 ; Hg=76-61 ; Cl=20.32 per cent. The approximate constancy of the composition of the precipitate obtained under such varying conditions of temperat'ure arid con-centration of the liquid phase proves that it is a single phase whilst the fair agreement of the atomic ratios with those of the compound HgCl,,H,NHgCl shows that i t can be regarded as this compound with small amounts of the constituents of the solution in solid solutioii. Conclusion. (1) A new additive compound of mercuric chloride and ammonia (2) StaBmholm's statement' that a compouiid Hg,Cl3NH, exists of the formula 3HgC1,,2NH3 has been prepared. has been confirmed. SIR LEOLINE JENKINS LABORATORY, JESUS COLLEGE, OXFORD. [Received November 8tk 1917.

ISSN:0368-1645    

DOI:10.1039/CT9181300074

出版商:RSC    

年代:1918

数据来源: RSC