Societies and Academies

Abstract

LONDON. Chemical Society, April 2.—Mr. W. Crookes, F.R.S., Vice-President, in the chair.—The following papers were read:—Citraconfluorescein, by J. T. Hewitt. Lunge and Burckhardt have shown that maleic anhydride is capable of yielding a fluorescein; the author has obtained the corresponding fluorescein from citraconic anhydride, by the action of resorcinol in the presence of sulphuric acid. Citraconfluorescein is easily soluble in alcohol and glacial acetic acid, fairly soluble in water; the aqueous solution is yellowish-brown and shows a green fluorescence.—Ethylic thiacetacetate, by Dr. C. T. Sprague. Hübner obtained ethylic thiacetacetate by the action of sulphur monochioride, S2Cl2, on ethylic acetacetate. It has since been obtained by Delisle by the action of sulphur dichloride, SCl2, on ethylic acetacetate; by Schönbrodt by the action of sulphur on the copper derivative of ethylic acetacetate; and by Michaelis and Phillips from thionyl chloride and ethylic acetacetate. Buchka proposed the formula S(CH.Ac.CO2Et)2, but an alternative formula, S(O.C: CH.CO2Et)2, was suggested by Delisle. The author describes the preparation of the substance and the products of its interaction with hydrazines; and shows that it behaves towards phenylhydrazine in the same manner as ethylic acetacetate. The results are in accordance with the formula proposed by Buchka.—The function of chlorine in acid chlorides as exemplified by sulphuryl chloride, by H. E. Armstrong. A number of experiments carried out during recent years in the authors laboratory show that sulphuryl chloride, SO2Cl2, acts on benzenoid compounds simply as a chlorinating agent. Sulphuryl chloride is easily formed by the direct union of sulphur dioxide and chlorine in the presence of a catalyst, such as camphor. charcoal, or acetic acid; it is a highly mobile liquid of low boiling-point, and is acted on with extreme slowness by water and alkaline solutions. It is an inert substance possessed of properties by no means such as are usually regarded as characteristic of acid chlotides. The chlorine is apparently but loosely held, and is easily withdrawn by a compound having an affinity for chlorine, such as naphthalene. On warming a mixture of this hydrocarbon and sulphuryl chloride, SO2 is evolved and naphthalene tetrachloride is produced. The author doubts whether the chlorine in acid chlorides is possessed of special activity, and is inclined to the view that the activity of acid chlorides is conditioned by the oxygen rather than the chlorine; this view being supported by the observations of Wagner and Saytzeff and the later ones of Pawlow (Annalen, clxxxviii. 104). The author also discusses the action of SO3HCl, and the analogous compound SO3. EtCl, and points out that pyrosulphuryl chloride, S2O5Cl2, behaves much as if it consisted of SO3 and SO2Cl2.—The ation qf nitric acid on the lignocelluloses, by C. F. Cross and E. J. Bevan. Dilute nitric acid attacks the ligno-celluloses when heated with them at 60°, with the formation of a bright yellow derivative of lignone and nitrous acid On further interaction, large quantities of nitrous oxide, N2O, are evolved, together with carbonic anhydride and a small proportion of nitric oxide. A sensible quantity of hydrogen cyanide is also produced, the proportion being increased by increase of temperature. The observations point to the entrance of the NOH residue into the lignone molecule; its interaction with nitrous acid being finally the displacement of H2 by O. The reaction is probably general for compounds containing the NOH residue, and the authors suggest that attention be paid to the gaseous products of the interaction of nitric acid and carbon compounds, as calculated to elucidate their mechanism.—The Chairman, Mr. Crookes, gave a short verbal account of observations on the volatilization of metals in vacuo under the influence of an electric discharge.