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Abstracts of the Proceedings of the Chemical Society, Vol. 3, No. 31 |
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Proceedings of the Chemical Society, London,
Volume 3,
Issue 31,
1887,
Page 1-6
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摘要:
ABSTRACTS OF THE PROCEEDINGS OF THE C H E M I C A L S 0 C I E T Y. January 20t11, 1887. Dr. Hugo Muller, F.R.S., President, in the C hai r. Certificates were read for the first time in favour of Messrs. Leonard Dobbin, Ph.D., 4,Cobden Road, Edinburgh ; Edgar Hall, Town House, Queenboro’, Kent ; Alexander Hay, 84, West Parade, Lincoln; John Steele Jackson, The College, Epsom; George McGowan, Bangor, Noyth Wales ; Henry Droop Richmond, Park Lane, Totten- ham; Arthur H. F. Kuppel, 52, Parrock Street, Gravesend; Henry Lloyd Snape, B.Sc., The Technical School, Xanchester ; W. Scruttoii, University College, London ; Arthur Stanley, 38, Trebovir Road, Earl’s Court, S.W.; Henry Weston Wallis, 7, Auckland Road, Clrtpham Junction, S.W. mIhe following papers were read :-1.“ Some Silicon Compounds and their Derivatives.” By J. Emerson Reynolds, X.D., F.R. S. Although large numbers of silicon analogues of carbon compounds are known, it is pointed out that we do not find among the former any well-defined representatives of cyanogen and its derivatives. The present investigation was commenced some years ago with the primary purpose of obtaining such compounds, if possible, and generally of examining reactions in which the silicon haloids-particularly the tetrabromide-and organic nitrogen compounds take part. In the course of the work R number of new bodies have been obtained, only a few of which can, however, be regarded as cyacogen-derivatives. The author, in this the first paper of n series, describes the action of silicon tetrabraniide on thiocarbamide, as the products obtained in this branch of the enquiry were exhibited at the conversazione of the Royal Society last June.It is shown that silicon tetrabromide in benzene solution acts in a very remarkable manner with thiocarbamide, the latter affording a condensed amide with which the tetrabromide unites. Eight mole- cules of thiocarbamide combine with only one of' silicon tetrabromide at the temperature of boiling benzene. Attempts to make this aniide unite with a larger proportion of the bromide only lead to clecomposi- tion. The product is a thick liquid at a temperature 65" C., below the fusing point of pure thiocarbamide (140" C.), and becomes solid at ordinary temperatures. Solvents of the tetrabromide do not extract any from this product, nor is it dissolved by any liquid withouh decomposition.When boiled with anhydrous alcohol it affords a monobromo-deril-a-tive of pentathiocarbamide, which is obtained from the alcoholic solution in beautiful groups of silky crystals. At the sanie time bromethyl-thiocarbamide and bromethyl-ditlziocarbamicle are obtained along with ethylic silicates. DISCUssION. In reply to Mr. RTDEAL, said that in preparing Professor REYNOLDS silicon tetrabromide, it was essential to use silica which had been pecipitated in the gelatinous form and to mix it most intimately with the carbon (lampblack) ; the action of the bromine took place at an extremely high temperature.Replying to the President's question- Had analogoiis cornpounds been obtained from urea? he said that urea did react with silicon tetrabromide, but not in the same way as thiocarbamide. l)r. ARMSTRONGremarked that assuming the bromine to be the liiiking agent, it was notewoythy that in the silicon compound and :tlm in that of ethyl bromide with thiocarbamide the ratio was Br : BCXN,H, : this perhaps might be regarded as an indication that the thiocarbamide molecule had at least tlie formula C,S,N,H, ; the ratio in the remarkable compound with bromine was, however, cliff erent. 2. " Chromo-organic Acids. Part I.Certain Cl~rc~~ioxalates.~' By Emil A. Werner. This paper contains an account of the salts resulting from the combination of chromium oxalate with certain metallic oxalatea.A study of these compounds has led to the conclusion that they cannot be coilsidered as ordinary double salts, but are in point of fact salts of complex chromoxalic acids. A similar view of the constitution of these compounds was advanced by 1S'lalaguti in 1843, but strange to say has been entirely ignored, since all workers with these particular corn- ~)ouiicls (with the exception of Clarke and Kebler) have treated them as 3 double or triple salts. Malaguti’s view has been considerably extended, and new experimental evidence furnished in support of it; it has also been shown that the oxalic radicle can be displaced by those of other organic acids, salts of which have been obtained.The paper concludes with the description of a new series of chrom- oxalates, whose members are shown to be closely related to those already known. The following are examples of the fo,rmulm given by the author to the three classes of salts :-Blue salt. Red salt;. Green salt. DISCUSSION. Dr. JAPPthought that some of the provisional constitutional formuhe proposed by the author for the various series of chromoxalates. were open to criticism. In the formula for the salt of the “red series,” for example, two oxygen-atoms, united to oxalic acid radicles, were represented as satisfying each other’s affinities--an arrangement which would place these stable salts in the same category as the explosive peroxides of acetyl and benzoyl ; whilst at the same time the two chromium-atoms in the formula were doubly linked.Tt was only necessary, however, to suppose that these vacant affinities of the chromium-atoms were satisfied by those of the oxygen-atoms in order to represent the salts as perfectly normal, thuR :-KO*C202*O*Cr<o0> C202 ‘0> CZOZKO-C,O,*O.Cr< The constitution of the salts of the “green series ” was still more anomalous, as in these the chromium was represented as existing in a less saturated state than that in which it occurs in the chromous compounds. Mr. J. M. THOWONdrew attention to the interesting dichroic properties of the chsomaoxalates, the dichroism being especially marked in the case of the calcium salt described by Pro-EessorHartley.The difference in the extent to which they exhibit dichroism was very remarkable, as it distinctly decreased as the at0m.k weight of the metal forming the double chromoxalate increased, the dichroism of: the potassio-baric chromoxalate being small compared with that of the potassio-calcic chromoxalate or the potassio-llithic: chromoxalate- 4 Had the author observed the same diminution of dichroism with increase in molecular weight in the salts formed from the organic bases which were mentioned in the paper ? With the object of further examining the optical properties of these compounds, the speaker had recently prepared double po tassio-chromoxalates containing nickel and cobalt ; these salts, however, presented no specially marked dichroic properties.They are also more soluble than the calcium or barium salts, and more difficult to crystallise. Dr. FOSTERMORLEYsaid that the “ red salt,” as formulated, would be a chromous salt ; spectrum analysis might be expected to throw light on the question whether it actually was a compound of this order. From observations recently made in the laboratory of the University College, it appeared that the difference between the blue and red chromoxalates was of the same nature as between the known blue and red chromic salts. Dr. ARMSTRONG,agreeing with the previoiis speakers, said that 8 chromous salt, such as the red salt was represented to be, ought, like all chromous Salts, to be a powerful reducing agent : not a word was saidin the paper to indicate that such was the case.The green salt, according to the formula given, would be still more oxidisable: it was inconceivable that such a salt should be formed in presence of alkali and air. He thought all three were chromic salts. Professor REYNOLDS,by whom the paper was read, said in reply that differences in dichroic properties such as were referred to by Mr. Thomson had been noticed in the case of the salts of organic radicles. The author was studying the spectroscopic behaviour of the salts described. 3. “ Note on the Constitution of the Double Chromic Oxalates.“ By W. N. Hartley, F.R.S. Some years ago (Proc. Roy. Xoc., 21, 499) the author described a remarkable dichroic salt, a potassio-calcium chromoxalate, and at the same time he prepared a large number of similar salts, the analyses of which were not completed in time for publication. These were potassio-chrome oxalates containing strontium, barium, lithium, and thallium.Excepting the lithium and calcium salts they did not possess any striking optical properties. They crystallised freely. On account of the manner in which these salts were formed, for instance :-u. By dissolving chromic hydrate in oxalic acid and adding the bases or their carbonates ; b. By preparing the red potassium chromic oxalate, Cr”’KCa0,*3H20, and adding neutral potassium oxaIate thereto ; 5 also by reason of their reactions with calcium, strontium, and barium salts, he came to the conclusion that they were really derivatives of a distinct acid which might be termed chromoxalic acid, 2nd the formnla following would represent its constitutioiz-Crr''O,( C,O,*OH),.The following reasons may be stated as affording grounds for this view :-1. The chromium is not precipitated by alkalies. 2. When alkali is added a soluble salt of the alkali is produced instead of a pyecipitate of chromic oxide or hydrate. 3. The carbonates of the alkalis give soluble salts of the alkalis and no precipitate. 4. The formula given is the only one which explains the formation of such salts as K3Cr"'*3CZ0J. 5. The blue salts such as K3Cr"'*3C204 are formed with greater ficility than the red salt KCr"'*2C204. 6. The blue salts give none of the reactions which are characteristic of oxalates, such as precipitation with chlorides of calcium, barium, &c.7. The blue salts can be formed from the red, and the potassio- calcium chromic oxalate can be made by boiling calcium oxalate with the red salt according to the equation 4. "Remarks on recent Papers by A. Baeyer and J. Thomsen 011 The Constitution of Benzene.' '' By Alex. K. Miller, Ph.D. The author contends that most of Baeyer's arguments fail to carry much weight, since they are based on reactions which admittedly involve intramolecular changes. Such reactions might be used with equal force either in support of or against almost any formula, accord- ing to the way in which the isomeric change be assumed to take place. It is shown, for instance, how the conversion of dihydroxyterephthalic ether into smcinosuccinic ether may be explained with the help of the pyism formula as readily as with Kekulk's symbol.The author also points out a weak point in the argument which Baeyer brings forward against the prism formula. Finally it is pointed out that Baeyer's arguments in support of the existence of a double bond in benzene are founded upon data which rnay perhaps be used as an argument in favour, but certainly do not prove the existence, of a pair of clonble bonds. With reference to Thornsen's octahedral symbol for benzene, it is stated that the advantages claimed for it, namely, that it is a perfectly symmetrical space representation which admits of three possible disubstitution-derivatives, and three only, are perfectly well founded.ci It is, however, pointed out that the symbol differs in some important respects from KekulB’s symbol; it is impossible, for instance, to represent qninone as a diketone, the only representation possible being that in which each oxygen-atom is united by one afinity only to a carbon-atom; another difference is that Thomsen’s symbol renders possible four disubstitution-derivatives of hexahydrobenzene. Finally, certain synthetical reactions such as the formation of succiiiosuccinic ether from succinic ether cannot well be represented with the aid of the symbol in question. In conclusion, the author expresses the opinion that neither Baeyer’s nor Thomsen’s paper has contributed to the solution of the problem of the constitutioii of benzene. At the next meeting, on February 3rd, there mill be a ballot for the election of Fellows, and the following papers will be read:- “ An Explanation of the Laws which govern Substitution in the case of Beiizenoid Compounds.” 13y Dr. Armst>rong. “ The Synthetical Formation of Closed Carbon chains.” Part 1. “ Some Derivatives of Tetramethylene.” By Dr. vlr. H, Perkin, Jnnr., and H. Coleman. Part 11. “ Some Derivatives of Pentamethylene.” By Dr. W.H. Perkin, Junr. ~ ~~ HARRISOS ASD SOKS, PRIKTERS IN OK.DIKAI<P TO HEIt NAJLS7’P, ST. MAKTIh’h LAKC.
ISSN:0369-8718
DOI:10.1039/PL8870300001
出版商:RSC
年代:1887
数据来源: RSC
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