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Proceedings of the Chemical Society, Vol. 16, No. 219 |
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Proceedings of the Chemical Society, London,
Volume 16,
Issue 219,
1900,
Page 33-48
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摘要:
Issued 22/2/1900 PROCEEDINGS CHEMICAL SOCIET’Y. EDlTED BY THE XECRETARIEX. Vol. 16. No. 219. February 8th, 1900. Extra Meeting. Sir HENRY LL.D.,ROSCOE, F.R.S., Vice-president, in the Chair. The President, Professor T. E. THORPE,LL.D., F.R.S., delivered the Victor Meyeli. Memorial Lecture. Victor Meyer was born in Berlin on September Sth, 1848, and died in Heidelberg on August Sth, 1897. He was at the time of his death President of the German Chemical Society, and had been an Honorary Foreign Member of the Chemical Society since 1883. As a friend of nearly 30 years’ standing, and as one who studied with him under Bunsen, the President had acceded to the request of the Council to record its appreciation of the remarkable services Victor Meyer rendered to the science which he cultivated during the all too short period of his activity with such striking assiduity and success.Some account was given of Meyer in his student days in Heidelberg, of his early connection with the University Chemical Society, and of his work as one of Bunsen’s assistants. In 1868, he entered Baeyer’s laboratory at the Gewerbeakademie in Berlin, and began the series of half-dozen investigations which characterised his activity during his three years’ stay in the German capital. Special reference was made to his memoir on the constitution of the disubstituted benzenes, and upon his method of introducing a carboxyl group into the molecule of aromatic compounds by the action of sodium formate upon the patass- ium salt of the aromatic sulpho-acids, and it was shown how the results of his observations led to a revision of the views then held with respect to the orientation of the radicles in the ‘(ortho” and ‘‘ meta ” (salicylic) series. Meyer’s success as a private teacher induced von Baeyer to recom-mend him to Fehling, who sought assistance, especially in the teaching of modern organic chemistry and in practical work in connection with his duties at the Stuttgart Polytechnic.Although he remained in Stuttgart barely a year, he there made one or two discoveries, espe- cially that of the nitro-compounds of the fatty series, which at once stamped him as an original investigator of a very high order. From Stuttgart he was called to Zurich as the successor of Wislicenus, who had beenmoved to Wurzburg, and, when barely 24 yearsof age, he was elected Ordinarius and Director of the chemical laboratory of the Polytechnic.The 13 years of Meyer’s stay at Zurich constitute the most fruitful and the most brilliant period of his career ; before its close he had brought himself within the foremost rank of contemporary investi- gators. Some idea of his wonderful power of work, and of the stimulus he gave to others, may be gleaned from the fact that during that period the Zurich Laboratory gave close on 130 papers and memoirs to chemical literature. Special stress was laid upon the elaborate investigation of the nitro-compounds of the alkyl series and their derivatives, which continued to occupy Meyer and his pupils for many years.Reference was made to the discovery of the nitrolic and azaurolic acids, and of the pseudonitroles, and it was pointed out how the characteristic colour reactions afforded by the behaviour of nitrous acid with the primary and secondary nitro-paraffins, and its inability to act upon the tertiary compounds, offered a ready means of distinguishing primary, secondary, and tertiary alcohol radicles. It was shown how the same line of inquiry led to the dis- covery of the group of the azines and of the ketoximes and aldoximes, and what the influence of these discoveries was upon the stereo-chemistry of nitrogen. It was at Zurich that Meyer devised his various methods of deter-aining vapour densities, and it was pointed out what an important influence the simple and extremely convenient process, known as the air displacement method, has had upon our knowledge of the true molecular weights of substances.Meyer’s work on the dissociation of the halogens was especially referred to. Pyrochemical problems, in fact, continued to interest him to the end, and he was quick to take advantage of any hint which seemed to promise the possibility of their solution. In a lecture before the Naturforscher Versammlung in Heidelberg, he regretted that the lack of vessels of sufficiently refractory material prevented him from working at the higher limits of temperature even then attainable, “There can be no doubt,” he said, ‘‘that new and undreamt-of discoveries will manifest themselves -that a new chemistry will disclose itself-when we are furnished with vessels that will enable us to work at temperatures at which water can no longer exist, and at which oxyhydrogen gas becomes an unin flamma ble mixture.” 35 In the autumn of 1882, Meyer mas requested to undertake the delivery of the series of University lectures on benzene derivatives which had been interrupted by his friend Weith’s death. It was in the course of these lectures that he came upon what is, perhaps, the most brilliant of all his discoveries-that of thiophen. He desired to show his class the indophenin reaction of Baeyer, which, at that time, was held to be indicative of benzene ; but, to his astonishment, not a trace of the characteristic blue colour made its appearance, although, as was his wont, he had rehearsed the experiment just prim to the lecture.It happened lhat his assistant had handed to him a sample of the benzene which had been made in the lecture course by heating benzoic acid with lime, and at once drew his attention to the fact that the rehearsal had been made with the ordinary laboratory supply, which, of course, was derived from coal tar. It was soon definitely established that it was only coal-tar benzene that gave the indophenin reaction. Meyer’s first idea mas that it might be occa-sioned by an isomeric, a second benzene found in coal tar; but he quickly ascertained that the reaction was due to some sulphuretted product arid that Eaeyer’s indophenin was a sulphur compound. He found that coal-tar benzene, after repeated shaking with oil of vitriol, no longer reacted with isatin, and it was among the sulphonic acids so Formed that he discovered the reactive substance.This he was at first inclined to call t?Linnthren, then thiophun, next thiol, and lastly thiophecrz, to denote that it was a sulphur-containing substance giving derivatives analogous to those of phenyl. Within about six months of his first observation, he was in a position to show to the Swiss Natur-forscher Versammlung, by actual preparations, that its chemistry was hardly less extensive than that of benzene itself. In 1888he published, in the form ol a monograph-Die Thiophengwppe (Braunschweig : Vieweg u.Sohn)--an account of its condition at that time, from which it appears that, during the preceding five years, no fewer than 106 contributions to its history had been made from his own laboratory, and some 40 from those of others. On the death of Hubner, Meyer received a call to Gottingen, which he accepted, and where a new laboratory was to be built for him. Here he continued his pyrochemicsl work, and his investigation of the thiophen derivatives, and began with Paul Jacobson the admirable Text-book of Ovganic Chemistry, which, in the critical selection and arrangement of its material, is unsurpassed. With Auwers, he resumed the study of benzil and its derivatives, which he had begun with Wittenberg and Goldschmidt, and with Munchmeyer he com-menced the study of the behaviour of phenylhydrazine towards various groups of oxygen compounds.With Demuth, he undertook the investigation of the sulphuranes. Other notable papers of this period were on isophthalaldehyde; on the negative nature of the phenyl group ; on the thio-derivatives of deoxybenzoin and its analogues (desaurins); and with Riecke on the carbon atom and valency. Stereochemical questions-we owe the phrase to Meyer-occupied much of his thought at this period. His perspicacity and insight are well illustrated in the lecture he gave to the German Chemical Society, in 1890, on the results and aims of steraochemical research, It is of interest to the student as giving a fairly complete historical account of the development of space formuls, and more especially for the criticism of the work of Baeyer and Wislicenus on the stereochemical formuls of single-, dquble-, and treblc-linked carbon compounds, and of the stereochemical conceptions of Hantzsch and Werner in the case of nitrogen compounds. To this period belongs also his work on the aromatic nitriles, on tetramethylsuccinic acid, and on the oximes of phensnthraquinone.Meyer was not destined to remain long in Gottingen. The new laboratory was barely finished when, in 1889, he received a call to Heidelberg, as successor to Bunsen. To Heidelberg accordingly he went with the coveted title of Geheimrath and the promise of a new and enlarged laboratory. Although only forty years of age, he was now, so far as worldly position was concerned, at the summit of his career. In conjunction with a number of his pupils he began the investigation of the conditions determining both the gradual and the explosive combustion of gaseous mixtures, notably of electrolytic gas, and of the simpler hydrocarbons with oxygen.In the case of mixtures of aliphatic hydrocarbons. with equivalent amounts of oxygen, it appeared that the temperature of explosion falls as the number of the carbon atoms in the molecule increases; that it is probably lower for primary than for corresponding secondary hydrocarbons ;and is less for hydrocarbons containing a double bond than for those containing only single bonds, and is still less for those containing a triple bond. In 1892, Meyer and Wachter announced the existence of the iodoso- compoimds, a series of aromatic derivatives in which the monovalent group I0replaces hydrogen.The study of these compounds led to the discovery of the remarkable substances known as the iodonium bases -compounds in which two of the vnlencies of the trivalent iodine atom are satisfied by aromatic radicles, while the third is satisfied in the free base by hydroxyl, and in the salts by an acid radicle. The iodonium bases are readily soluble in water, are strongly alkaline, and in their behaviour, as in that of their salts, show a remarkable simi- larity with the derivatives of silver, lead, and more particularly thallium. Reference was also made to the study of the conditions determining the formation and hydrolysis of ethereal salts of aromatic acids wbich 37 occupied Meyer, in conjunction with his pupils, and more especially Sudborough, from 1894 up to the year of his death.Meyer contributed to the literature of chemistry, either alone or in conjunction with his pupils, upwards of 300 memoirs and papers. As the director of a large chemical laboratory, and as a laboratory teacher, Meyer worthily followed in the footsteps of Bunsen. He was an admirable lecturer, clear, vigorous, and extremely lucid, and his lectures were most popular. As a teacher, he had a wonderful faculty of infusing enthusiasm into his students. His literary ability, com- bined with his power of exposition, made him an admirable writer of popular science articles.His merits were recognised in every land where science is cultivated, and he was an Honorary Member of many Continental academies. The Royal Society awarded him the Davy Medal in 1891, and in the spring of that year he attended the celebration of the Jubilee of. the Chemical Society, and the eloquent words which he idered in responding to the toast of '' Our Foreign Members " will not readily be forgotten by those who attended the banquet on that occasion. On the motion of Professor DEWAR, aseconded by Dr. ARMSTRONG, vote of thanks was passed to the President for his lecture. February 15th, 1900. Professor THORPE,F.K.S., President, in the Chair. Measrs. J. Dewhirst, Edgar M. Chapman, and Thomas A.Henry were formally admitted Fellows of the Society. It was announced that the following changes in the Council were proposed by the Council :-As Vice-Y./.esz'deizts-Professor Divers, M.D., F.R.S., and Dr. T. Stevenson, vice Professor Karnsay, F.R.S., arid Yrofessor Emerson Reynolds, F.R.S. As Ordinary Members of Council-Dr. Cfhattaway, Professor Collie, F.R.S., Professor Augustus Dixon, M.D., and Mr. W. J. PcJpe, vice Mr. Bevan, Dr. Moody, Dr. H. F. Morley, :tiid Professor Smithells. Certificatea were read for the first time in favour of Messrs. Alexander William Bain, 2, Muswell Rise, Highgate, K.; Arthur Charles Davis, 3, Vinery Road, Cambridge ; Noel Fielding Deerr, 26, South Parade, Chelbea, S.W. ; Adolf Liebmann, 10, Marsden Street, Manchester ; Frederick Thomas Munton, The Oak House, Winsford, Cheshire ; James Wallace Sandford, Adelaide, S.A.; Bertram D. Steele, 40, Herndale Road, London, S.W. A ballot for the election of Fellows was held, and the following wore subsequently declared duly elected :- 38 Frederick Nolan Baker ; Alexander Hutcheon Bennett ; Sidney Calvert, M.A., B.Sc. ; Oscar Joseph Cole, B,A. ; William Francis Cooper, B.A. ;Thomas Cuthbert Davison ; Harry M. D‘Lwson, B.Sc., Ph.D. ;Stephen M. Dixon, B.A. ; Alexander Findlay, M.A., B.Sc. ; James Foulds ;Granville Reginald Gee ; Julius Geldard ; Robert W. Gray ; Alfred William Harvey ; Herbert William Hart ; Adam Houston ; Henry William Hutchin ; Henry Jackson, B.A., B.Sc. ; Thomas Goode Joyce, 6.Sc.; W. C. Robert Kynaston ; Arthur Robert Laws; Thomas Ebenezer Mackenzie; Willam Mair; A. W. Cran-brook Menzies, ’M.A., B.Sc. ; J. L. Rutgers Morgan, M.A., Ph.D. ; Edgar Ford Morris, M.A. ; Herbert Newall Morris ; Ernest Brooks Naylor, B.Sc. ; James Fraser Readman ; Walter A. Riley ; James McConnell Sanders ; Fred Pilkington Snrgeant ; Edward Shrapnel1 Smith ; James Hart-Smith ; Bertxam Vincent Storr, B.Sc. ; Archie Hugh Strong ; Gusthvus A. Waterhouse, B.Sc. ; Leonard Philip Wilson, Messrs. A. W. Crossley, F. J. M.Page, acd E. W. Voelclrer were appointed to audit the Society’s accounts. Of the following papers, those marked * were read. *17. ‘(Ammonium amidosulphite.” By Edward Divers and Masataka Ogawa. When dry enough, ammonia does not combine with sulphur dioxide at a low temperature.When less dry, it does so, with such rise of temperature that the product of the union is at once partly decom- posed. But by dissolving the ammonia in dry, alcohol-free ether, and passing the sulphur dioxide into the solution, kept very cold, the product is precipitated undecomposed. It is colourless, very deliques- cent, and unstable in the air. It dissolves in water with a hissing sound, and, when the water has been well cooled, yields a solution which gives the reactions of ammonium sulphite oniy. It is also very soluble in absolute alcohol, forming the salt lately described by the authors, ethyl arnmoniumsulphite. It is formed from two mols. ammonia and one mol. sulphur dioxide.In a dry atmosphere, at temperatures such as 35O, it loses nearly half of its ammonia, as well as a little water. After the decomposition, no sulphite-forming sub- stance remains, and the mass is somewhat orange-coloured from the presence of a very small quantity of a red substance. A very little sulphate is also present, but the residue consists mainly of substances t8hecomposition and nature of which are not yet fully determined. They seem to be thio-amido-sulphonic compounds, as yet unknown, which, by heat, by spontaneous partial hydraticn, or by treatment with ammonia in alcoholic solution, yield sulphur, sulphur dioxide, sulphate, thiosulphate, amidosulphate, imidosulphate, and, almost certainly, sulphamide ; when dissolved in water they give a reaction with silver nitrate, closely resembling, yet not that of a trithionate, ;for when acidified, their solution gives no sulphur or sulphur dioxide or only mere traces until it has been heated under pressure or for a long time.The undecomposed salt appears to be correctly named ammonium amidosulphite, and to have the formula NH2*S0,*NH,. The prepara- tion of this salt shows Rose’s assertion, that the gases unite only in equal volumes forming an orange substance which at once decomposes with water into sulphate and trithionate, to be altogether wrong and fo be due to his having failed to prevent the decomposition of the product first formed. “18. ‘(On the products obtained by heating ammonium sulphites, thiosulphate, and trithionate.” By Edward Divers and Masa- taka Ogawa. The authors have ascertained that anhydrous ammonium sulphite and pyrosuZphite sublime unchanged at about 150° in a current of dry nitrogen, the vapours being no doubt the dissociated gases.At a temperature somewhat higher, ammonium trithionate decomposes into sulphur dioxide, sulphur, and ammonium sulphate. At about 150°, ammonium tJtiosulpJwte decomposes almost entirely, leaving a residue of sulphur and giving a sublimate of anhydrous ammonium sulphite ; very small quantities of ammonia and hydrogen sulphide are also given off, giving rise possibly to a trace of trithionate. According to Spring, ammonium thiosulphate sublimes unchanged, except for tem-porary dissociation. To obtain the above results, moisture must be absent : the effect of slowly heating hydruted ammonium sulphite in a current of dry nitrogen is partly to dehydrate it, partly to con-vert it into pyrosulphite, at about 120’; and then at about 150°, the residue decomposes into sulphur dioxide and ammonium sulphite (approximately hemib ydra ted) which sublimes.Ammonium tritJvionccte, a very deliquescent and unstable salt, not hitherto described, was prepared from the potassium salt by the use of hydrofluosilicic acid and ammonia, being much too soluble to admit of preparation by Plessy’s process for the potassium salt. Ammonium suZphite was conveniently precipitated by saturating its concentrated solution with ammonia in a cooling mixture, and the pyrosulphite by similarly saturating its solution with sulphur dioxide. Anhydrous ammoniumsulpJde was obtained by exposing the hydrated salt in a‘ desiccator over potash in an ammoniacal atmosphere.40 *l9. 4L The colour of alkali nitrites.” By Edward Divers. As Boguski (J,Russ. Chem. SOC.,1899, 31,543) has published his observation that a solution of sodium nitrite had a slight yellow colour which he could not remove, and which he attributes to the presence of an impurity, the author wishes to recall attention to his own state-ment (Trans., 1899, 75, 86) that alkali nitrites have a slight yellow colour, especially in solution, and to Groves’ statement in denial of its accuracy (Proc., 1898, 14, 222). The author desires now to claim accuracy for his own statement.The colour of the potassium salt is much more manifest than that of the sodium salt, principally because of its ability to yield exceedingly concentrated solutions. Solutions of potassium nitrite, three parts of salt in one of water, are strongly yellow, particularly when thoroughly free from turbidity. Solutions of equal strength are equally coloured, whatever has been the source of the nitrite. Alkali nitrites are yellow in the fused state. The author is confident that Boguski’s promised endeavour to remove the colour of sodium nitrite will be as futile as were those of chemists, long years ago, to remove the pink colour from manganous salts. Boguski’s observation that the solid nitrite is sometimes ap-parently without colour, depends upon the well known optical effect of fine division in lessening the colour of transparent solids.“20. (‘Solubility of mixed potassium nitrite and nitrate.” ByEdward Divers, By crystalliving out, as far as possible, the nitrate which is mixed with potassium nitrite in its usual method of preparation, there remains a mixture of about three parts of nitrite to one part of nitrate, and this constitutes the ordinary nitrite of commerce. This mixture is soluble in one-fourth its weight of water, although the pure nitrite. requires one-third of its weight, and the pure nitrate about four times its weight of water to dissolve it. Accordingly, when a solution of three parts pure potassium nitrite in one part water is digested with. powdered potassium nitrate at the common temperature, it readily dissolves up one part of this salt.DISCUSSION. In reply to remarks by Messrs;. BAKER, W. P. BLOXAM,and SCOTT, Dr. DIVERSsaid that the ammonium amidosulphite rapidly deliquesced in air, and he quite agreed with Mr. Bloxam’s observation as to the great activity of hydrated ammonium sulphite with regard to atmo- 41 spheric oxygen, As Rose had taken no precautions to maintain a low temperature during the reaction, there was .no doubt that the com- pound resulting from the combination of two volumes of ammonia with one of sulphur dioxide gave off half of its ammonia again under the influence of the high temperature produced in the reaction. “21.‘(The combination of sulphur dioxide with oxygen.” By Edward John Russell and Norman Smith. The authors have found that when a mixtureof sulphur dioxide and oxygen acts on certain oxides, in addition to the absorption of the sulphur dioxide, part of the sulphur dioxide and oxygen combine forming sulphur trioxide, this being apparently due to the “surface action” of the oxide. The extent of this “surface action” varies with the nature and physical conditions of each oxide. No sulphur trioxide was ever found unless a simultaneous absorption of sulphur dioxide occurred ; when manganese peroxide and sulphur dioxide, dried by phosphorus pentoxide, were brought together, no absorption took place, nor was any sulphur trioxide produced on the addition of dried oxygen.If a mixture of dried sulphur dioxide and oxygen be passed over well-dried platinised pumice heated to 400-450°,very little sulphur trioxide is formed, and the drier the materials the less is the combination. “22, 6‘ Notes on the estimation of gaseous compounds of sulphur.” By Edward John Russell. In this paper, volumetric methods of analysis are given which have been found to work satisfactorily in the estimation of sulphur dioxide, hydrogen sulphide, cnrbonyl sulphide, and carbon disulphide in gaseous mixtures. It is found that, except, in the case of sulphur dioxide, absorption methods are not reliable; as a rule, by far tha most satisfactory method is to explode with oxygen. In this ex-plosion, sulphur dioxide and sulphur trioxide are both produced, the amount of the former being determined directly, and that of the latter calculated from the contraction observed after explosion.Sul-phur dioxide is best estimated by absorption with a pellet of lead peroxide, since this substance, if freshly washed and not too dry, exerts but little of the surface action which tends to cause some of the sulphur dioxide to combine with part of the oxygen to form sulphur trioxide. "23. 6L The influence of the nascent state ' on the combination of dry carbon monoxide and oxygen." By Edward John Russell. The author has studied several reactions in which carbon monoxide and excess of oxygen were brought together in the flame of an explosion, one or both being in the nascent condition.Combustion Was rarely complete, and the amounts of carbon monoxide left un-burnt were found to be very similar to those left unburnt in Dixon's experiments (Trans., 1896, 784), in which dried mixtures of carbon monoxide and oxygen were fired by adding carbon disulphide and oxygen and sparking, although in the present experiments one of the substances (carbon monoxide) was in the nascent condition, whilst in Dixon's experiments it was not. It seems, therefore, that the nascent condition has no great effect in promoting combination between carbon monoxide and oxygen, although the high temperature produced by a violent reaction has a very considerable effect. The substances used as sources of nascent carbon monoxide were carbonyl sulphide and nickel carbonyl ; and for nascent oxygen, chlorine inonoxide and chlorine peroxide.It was discovered incidentally that mixtures of pure carbonyl sulphide and excess of oxygen are not exploded by an electric spark. If, however, a slight amount only of impurity is present an explosion takes place,' but combustion is not complete, carbonyl sulphide re-maining unburnt in large quantity, along with carbon monoxide, produced by the decomposition of some of the carbonyl sulphide. If the impurity is greater, the combustion is complete. "24. (( Asymmetric optically active tin compounds. Dextromethyl-ethyl-n-propyl tin iodide. Preliminary note. By William Jackson Pope and Stanley John Peachey. 'Hitherto no substance containinganatomof tinattached to four different groups has been obtained, owing to the lack of general methods for their preparation.The authors find that compounds of the type SnXIX1[X1*LXIVcan be readily prepared by aid of the following series of reactions from &he trimethyl tin iodide described by Ladenburg and Cahoura : (1) 2Sn(CH,)31 +Zn(C,H,), =2Sn(CH,),(C2H5) + ZnI,. (2) Sn(CH,),(C,H,) +I, =Sn(CH3)2(C2H5)I+ CH,I. (3) 2Sn(CH,),(C,H5)I + Zn(C,HY), =2Sn(CH,),(C,HS)(C3H7) + ZnI,. (4) 8n(CH3),(C,Hj)(C3H7) +I, =Sn(C!K,)(C,H,)(C,H,)I + CH,I. Externally compensated ~nethyZethyZ-n-p1.opyl tini~dide,tE~>Sn<:~~~, 25 43 the final product of reaction (4),is a faintly yellow oil boiling at 270" without decomposition ;it is almost insoluble in water, and its vapour exercises unpleasant effects on the mucous membrane.On agitating the iodide with a warm aqueous solution of a molecular proportion of silver dextrocamphorsulphonate and evaporating the filtered liquid, a copious deposit of clextromethylethyl-n-propyl tin dextro- 6c&mphorsuZphortate,Sn(CH,)(C,H,)(C,H7)(Cl0H,,OSO3), was obtained ; $he salt is only sparingly soluble in cold water, and crystalliaes in !ustrous, square plates melting at 125-126O. In dilute aqueous solu- fion, it has t,he molecular rotation [MID = + 95', so that for the mono-CH*\ basic radicle, C,HiLSn-, [MI, is about +45'. C,dOn evaporating the mother liquor from which this salt had separated, further deposits of the same salt were obtained until all the water had been expelled, and the authors have been unable to isolate a salt of the %svo-base; this behaviour seems due to the conversion of the lsvo-base into the dextro-base by continued racemisation in the following manner.The solution of externally compensated base with dextro- camphorsulphonic acid deposits a portion of its dextro-base as the sparingly soluble salt ; the excess of lzevo- over dextro-base remaining in the solution racemises as evaporation proceeds, a farther portion of dextro-base separates as salt, and racemisation of the residue again proceeds. This case is the first cjf the kind recorded, -and affords powerful support to Le Bel's hypothesis respecting the mobility of alkyl groups of low molecular weight in quaternary ammonium salts.On treating the freshly prepared cold aqueous solution of the dextrocamphorsul phonate with potassium iodide solution, dcxtro-.methylet?~~Z-n-propyltin iodide separates as a faintly yellow oil ;the highest specific rotation of the iodide which has yet been observed is i[aID = + 23' in ethereal solution. The rotation was, however, very variable, and, under conditions not yet understood, the separated iodide was optically inactive. This behaviour is due to racemisation. It should be noted that the discovery noted above, that racemisa- tion, due to intramolecular mobility, may cause rapid and complete conversion of an externally compensated base into one optically active isomeride, reopens the question of the space configuration of quadri- valent sulphur compounds which, in the light of previous knowledge, seemed to have been determined by our former rewlts (Proc., 1900, 16, 12).Having now shown that quadrivalent asymmetric tin compounds can exist in enantiomorphously related configurations possessing optical activity, it follows that the space configuration of quadrivalent tin compounds is of the tetrahedral type alreAdg established for carbon 44 compounds, and substances of the type of tin tetrachloride must now be regarded as true atomic compounds. Having proved that asym-metric pentavalent nitrogen compounds (Trans.,1899, 75, 1127) also give rise to optical activity in the same way that van’t Hoff and Le Be1 proved it fm carbon, it may be concluded that all enantiomorphous.compounds must be optically active. In Group IV of the periodic table the non-metal, carbon, is at the top, whilst the metal, tin, is near the bottom ;since both can give rise to optical activity in their asymmetric compounds, it is highly probable that all the elements in Group IV lying between these are capable of acting as centres of optical activity. Should this hold for the whole of Group IV,and as it has been shown to hold for nitrogen, the first member of Group V, all the elements of the latter group may be expected to act as optically active centres in appropriate compounds. Compounds of the types RXIX1lX1llX1v should.and QXIX1lXIK*X1vXv therefore be optically active, R being an atom of any element in Group IV, and Q an atom oE any element in Group V.The application of the redctions now described to other elements is in progress, and the authors hope shortly to communicate results obtained with quadrivalent lead compounds. 25. ‘‘Note on the refraction and magnetic rotation of hexamethyl-ene.” By Sydney Young, DSc., F.R.S., and Emily C. Fortey,. B.Sc. The specimen of hexamethylene obtained by one of the authors from Galician petroleum was found to contain a small quantity of a heptane. The hexamethylene was freed from the paraffin by fractional crystal- lisation, and its refraction and magnetic rotation were determined by Dr. W. H. Perkin, sen. The results obtained are given in the paper. 26.‘‘Apiin and apigenin. Part 11. Note on vitexin.” By A. a. Perkin. By the action of nitric acid on apigenin under varied conditions, four ni tro-derivatives have been obtained : mononityo-apigenin, C,,,H905(NO),, orange-yellow needles, m. p. about 302O, somewhat soluble in alcohol ;trinitro-apigenin (a),C,,H,O,( NO,),, yellow needles, m. p. about 296’ ; trinitro-upigenin (b), yellow needles, m. p. 245-24G0, and tetranitro-apigenin, C15H605(X02)4,almost colourless needles, m. p. 243-244’. With the exception of tho first mentioned, all dissolve with difficulty in the usual solvents. In preparing the mononitro- compound, dinitro-p-hpdvoxybenxoic acid was obtained as a deconl-position product, a further proof that apigenin does not contain a 45 catechol group (?'runs., 1897, 71, 805).Tetranitro-apigenin appears to be identical with the compound, C,,H605(N0,),, obtained from vitexin (Trans., 1898, 73, 1026), and as the decomposition products of both colouring matters are identical, vitexin must be a derivative of .apigenin. The formuls C,,H,oO,, and C',,H,,0,,(C,H,0)7 are now assigned tc vitexin and acetylvitexin, and it is suggested that vitexin is a stuble glucoside of upigenin, and that a like constitution may also apply to scoparin (Proc., 1899, 15,123), which, according to this view, is a glucoside of a Zuteolin monomethyl ether. Apiin, C27H32016,the glucoside of apigenin occurring in Apium petroselinum, is not converted by dilute nitric acid into nitro-apigenin, but into nitro-apigetrin, C,1H,,0,1N02, a yellow, crystalline powder very sparingly soluble in the usual solvents. This is the nitro- compound of a new glucoside, apigetrin, which differs from apigenin in containing but one sugar group.By prolonged digestion with dilute hydrochloric acid, it yields the above mononitro-apigenin. 27. 6L The yellow colouring principles of various tannin matters. VII." By A, (3. Perkin. The colouring matter of the leaves of Arctostaphy!os uva-ursi (bear-berry) and Hmmatoxylon Campeachiunurn (logwood) is quercetin, and this is accompanied by a second substance, probably myricetin, to which the green colour of its alkaline solutions are due. Gallotunnic acid occurs in some quantity in the latter leaves. The leaves of Rhzcs metopiurn contain gullotannin, myricetin, and a trace of quercetin, but the stem of this plant, unlike €2.cotinus, and R.rhodunthema is devoid of colouring matter. The sparing solubilities of acetylmyricetin and dibromoquercetin haye been employed for the separation of myricetin and quercetin. The leaves of Robinia pseudacacia contain a feeble colouring matter, acacetin, C,,Hl2O5, which yields an acetyl derivative, C,,H,,O,(C,H,O),, colourless needles, m. p. 195-19S0, and on fusion with alkali phloroglucinol, p-hgdroxybenxoic acid, and a trace of proto-catechuic acid. Acacetin contains one methoxyl group, on removal of which a colouring matter, C,,H,,O,, results, havi.ng the reactions of apigenin. It is thus probably an apigenin monometlql ether.The leaves of Myricu gale and Coriaria myrtifolia contain respectively myricetin and queycetin. Although a relationship frequently exists between the tanning and the colouring matters of the same plant (Trans., 1897, 71, 1138), there is no rule on this point, for exceptions are somewhat numeroue. 46 28. 'I Note on the bromo-derivatives of camphopyric acid." By ,J. Addyman Gardner. An atom of hydrogen in camphopyric acid may be readily replaced by bromine, by the action of the halogen in the presence of phosphorus. Two acids of the formula C,H,,BrO,, are thus obtained and are provisionally named, .a-and P-bromocamphopyric acid. These acids may be prepared either by treating camphopyric acid with phosphorus pentachloride and subsequently warming with bromine, or by mixing the acid with amorphous phosphorus and adding the proper amount of bromine. In either case, the product is poured into cold water, when part of the acid separates in the solid state and part is extracted with ether from the solution.The a-and p-acids may be separated by repeated crystallisation from benzene. If only a small amount of water is used to decompose the acid bromides, bromocamphopyric anhydride is also obtained. a-Bromocnmphopyric acid separates from benzene or chloroform as a very light, white, crystalline powder, melting at 167' with previous softening. It is very moderately soluble in hot benzene and chloro- form, but only slightly in cold ; it is also very soluble in water, ether, acetone and ethyl acetate.It is a dibasic acid, and forms very soluble sodium, barium and ammonium salts. a-Bromocamphopyric anhydride, C,H,,Br03, may be obtained by treating the acid in the usual way with acetyl chloride or acetic anhydride. It crystallises readily from benzene in well-defined, tabular crystals which melt at 226-227'. These crystals are very soluble in ether, acetone and ethyl acetate. p-Eromocamphopyric acid is more soluble in benzene than itsisomeride, and is obtained, though in very small quantity, from the mother liquors of the a-acid. It is a white, crystalline substance melting at 207-208', quite different in appearance from its isomeride. Its barium salt is soluble, and has the formula Ba(C,H,,Br04),,4H,0 ; this acid has not, however, been obtained in sufficient quantity for a more complete investigation.The same products are obtained when camphoic acid is similarly treated witli phosphorus pentachloride and bromine. a-Hydroxycamphopyric acid, C,H,,(OH)O,. If a-bromocamphopyric acid is heated for some time with a 10 per cent. solution of potash, then acidified with hydrochloric acid and extracted with ether, an oily acid is obtained which for the most part solidifies on standing. If this be boiled with benzene, the oily portion dissolves, and a white solid is left which, on crystallisation from water, may be obtained in well-defined, colourless, transparent crystals which melt at 206-207' 47 This substance is a dibasic acid and has the formula C,H,,O,.Its sodium and barium salts, which are very soluble in water, were analysed. It is only very slightly soluble in benzene, chloroform, and carbon bisulphide, but dissolves easily in ethyl acetate and in hot water ;the oil obtained along with it is apparently an unsaturated acid, but has not yet been obtained in a state of sufficient purity for in- vestigation. These substances are being prepared in quantity, and the author hopes before long to be able to bring before the Society a more complete account of their properties and reactions. ADDITIONS TO THE LIBRARY. I. Donation. Luff, A. P., and Page, F. J. M. A manual of chemistry, inorganic and organic, with an introduction to the study of chemistry. Ill.London 1900. From the Authors. II. Bg Pumhase. Gessmann, G. W. Die Geheimsymbole der Chemie und Medicin des Mittelalters. 111. Graz 1899. Pamphlet. Clowes, Frank, and Houston, A. C. Bacterial treatment of crude sewage (supplement to second report). Note on the deposit which accumulates on the coke fragments of the coke-beds at Barking and Crossness. From the Authors. 48 At the next meeting on Thursday, March lst, at 8 p.m., the follow- ing papers will be communicated :-‘‘Pilocarpine and the alkaloids of Jaborandi leaves.” By H. A.D. Jowe t t,I-D.Sc. Isomeric partially racemic salts containing pentavalent nitrogen,” Parts I to VII. By F. S. Kipping, D.Sc., F.R.S. New synthesis of indene,” By F. S. Kipping, D.Sc., F.R.S., and6‘ Harold Hall.Potassium nitrito-hydroximidosulphatesand the non-existence of dihydroxylamine derivatives.” By E. Divers, D.Sc., F.R.S., and T. Haga, D,Sc. I‘ Identification and constitution of Fremy’s sulphazotised salts of potassium.” By E. Divers, D.Sc., F.R.S., and T.Haga, D.Sc. “ Some acids obtained from a-dibromocamphor.” By A. Lapworth, D.Sc., and E. M. Chapman. Campholytic and isolauronolic acids.” By J. Walker and W. Cormack. “The configuration of the camphoric acids.” By J. Walker and J. K. Wood. ‘‘ The constitution of camphoric acid.” By J. Walker. An extra Meeting of the Society will be held on Thursday, March Sth, when a lecture on Recent Researches on Nitrification ” will be given by Professbr Warington, F.R.S. The Chair will be taken at 8.30 p.m. RICIIAKI) CLAY AND SUNS, LIAIITEU, LONlJVN hhb bUNGAF.
ISSN:0369-8718
DOI:10.1039/PL9001600033
出版商:RSC
年代:1900
数据来源: RSC
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