Abstract
LONDON.
Chemical Society, June 18.—“Prof. A. Crum-Brown, F.R.S., President, in the chair.—The following papers were read:—A note on some new reactions of dehydracetic acid, by Dr. J. Norman Collie. In preparing dehydracetic acid, by passing ethyl aceto-acetate through a red-hot tube, it is stated that alcohol is formed; the author finds that large quantities of ethylene gas and acetone are also produced. Dehydracetic acid is also volatile to a considerable extent with steam, and is decomposed by boiling with water to a small extent into carbon dioxide and dimethylpyrone. This latter decomposition is more readily effected by boiling the acid with strong hydrochloric acid. If 50 grams are boiled with ordinary fuming hydrochloric acid, the whole is converted into carbon dioxide and a soluble compound of dimethylpyrone with hydrochloric. acid. The barium salt of dehydracetic acid, (C3H9O5)2Ba, seems to be not a salt of the compound C3H8O4, but of the true tetraetic acid, C8H10O5. A very stable copper salt of the formula C24H25O9N3Cu is obtained if dehydracetic acid be added to a solution of copper acetate in a large excess of ammonia “The lactone of triacetic acid, by Dr. J. Norman Collie. In a former paper on the constitution of dehydracetic acid (Trans. Chem. Soc., 1890, 189) the author pointed out that if the formula which he proposed for dehydracetic acid was correct, it would be the δ lactone of tetracetic acid. And the following list was given showing the connection between the condensed acids formed from acetic acid: CH3CO.(CH2CO)2. CH2COOH, tetracetic acid; CH3CO.CH2CO.CH2COOH, triaeticacid; CH3COCH2COOH, diacetic acid; CH3COOH, acetic acid. At that time no acid corresponding to the triacetic acid was known. Since then the author has obtained the lactone of this acid by the action of 90 per cent. sulphuric acid on dehydracetic acid at a temperature of 130°-135°. The properties and reactions of the new compound are described.—The refractive power of certain organic compounds at different temperatures, by Dr. W. H. Perkin, F.R.S. The magnetic relations of substances when examined at temperatures wide apart show that certain variations take place after allowing for change of density. Experiments have been made by the author in reference to the refractive power of liquids under similar circumstances. The results show that the specific refractive power is not con tant for all temperatures. By comparing the lines A and F it was found that the dispersion was slightly diminished by rise of temperature. The results were calculated by the formula μ – I/d. When calculated by Lorentz's formula the numbers gave higher results for high temperatures than for lower ones.—Note on a volatile compound of iron and carbonic oxide, by Ludwig Mond, F.R.S., and Dr. F. Quincke (see NATURE, July 9, p. 234).—The formation of salts, a contribution to the theory of electrolysis and of the nature of chemical change in the case of non-electrolytes, by H. E. Armstrong. The author draws attention to the recent researches of Claisen, W. Wislicenus, and others, which clearly show that ethereal salts form compounds with sodium ethylate, and to the bearing which these results have on the theory of the formation of salts generally. It may be supposed that the acid and the “base” in the first instance combine, and that the salt is formed by subsequent interactions within the molecule. In like manner, acids form dissociable compounds with water, and by the occurrence of change within such systems, under the influence of electromotive force, electrolysis is effected. When the compound is highly unstable, the opportunity for change within its sy-tem is slight, the acid is a weak one, and its solution of relatively low conducting power. In the case of non-electrolytes, the occurrence of change may be supposed to occur within complex systems formed by the union of the interacting substances.—Dibenzyl ketone, by Dr. S. Young. The author finds that, in preparing the ketone by heating calcium phenyl acetate in a combustion furnace, only 27 per cent, of the theoretical yield is obtained. However, if the calcium salt be heated by means of the vapour of boiling sulphur, the yield of pure ketone amounts to 76˙6 per cent.—The vapour-pressures of dibenzyl ketone, by Dr. S. Young.— The vapour-pressures of mercury, by Dr. S. Young. Two additional observations of the vapour-pressures of mercury at 183°˙75 and 236°˙9 have been made, and, from the previous results of Ramsay and Young, the boiling-point and the vapour-pressures of mercury have been recalculated.
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Societies and Academies. Nature 44, 287–288 (1891). https://doi.org/10.1038/044287b0
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DOI: https://doi.org/10.1038/044287b0