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cyanate and guanidine hydrochloride. From an aqueous solution of molecular proportions of these salts and of hydrochloric acid in the cold, guanylcarbamide cannot be separated, although it seems to be formed since the solution gives the copper reaction of the base.

Guanylcarbamide nitrate, CN,H,O,HNO3, crystallises in white needles, the aurochloride in sparingly soluble, long, golden-yellow needles.

Guanidine cyanurate, CN,H5, (CNOH), obtained by adding guanidine carbonate to a boiling solution of cyanuric acid, crystallises in silky needles. W. P. W.

Preparation of Alkylamidoformic Chlorides and Alkyl Isocyanates. By L. GATTERMANN and G. SCHMIDT (Ber., 20, 118-121). When a stream of phosgene gas is passed over dry ethylamine hydrochloride heated at 250-270°, ethamidoformic chloride,

NHEtCOC1,

is formed in almost theoretical quantity. It is a colourless liquid, boiling at 92°, and having a very pungent odour. During the distillation, there is a dissociation into hydrogen chloride and ethyl isocyanate, but on cooling the chloride is re-formed. This compound is decomposed by water into ethylamine hydrochloride and carbonic anhydride. This substance is identical with that obtained by Habich and Limpricht by the action of hydrochloric acid on ethyl isocyanate, and by the distillation of diethylcarbamide hydrochloride. When the above chloride is distilled over quicklime, ethyl isocyanate is formed in almost the theoretical proportion.

This chloride, when treated with toluene and aluminic chloride, yields paratoluylethamide, CH,Me CONHEt, which crystallises in colourless, glistening needles, melting at 96°; this, when heated with strong potash, yields paratoluic acid. When benzene is substituted for toluene in the above reaction, ethylbenzamide, Ph.CO.NHEt, is formed, which forms glistening needles, melting at 67°, and boiling at 258-260°.

Methylamine hydrochloride and phosgene gas yield methamid formic chloride, NHMe-COCI. This crystallises in scales, melts at 90°, and boils (with dissociation) at 93-94°. In its properties and reactions, it resembles the ethyl-derivative. With toluene and aluminic chloride, it gives paratoluylmethamide, CH,Me-CO-NH Me. This is soluble in water, crystallises in colourless plates, and melts at 143°.

The above reactions appear to be generally applicable for the preparation of substituted amidoformic chlorides and of alkyl isocyanates. L. T. T.

Convenient Method for Preparing Brominated Fatty Acids. By A. MICHAEL (J. pr. Chem. [2], 92-95).-The chlorides of monobasic fatty acids are heated in a flask with the calculated amount of carefully dried bromine and about 50 c.c. of carbon bisulphide, until no more hydrogen bromide is evolved. The product is poured into water, partially distilled, and converted into the ethereal salt by treatment with absolute alcohol. From butyric acid, nearly the theoretical amount of ethyl a-bromobutyrate was obtained. The method works

well in the case of monobasic fatty acids, but not so well with succinic chloride, owing to the instability of the bromine-derivative when warmed. N. H. M.

Behaviour of Acetic Acid and some of its Derivatives towards Phosphorus Pentachloride. By A. MICHAEL (J. pr. Chem. [2], 35, 95-96).—When acetic chloride (40 grams) is boiled with phosphorus pentachloride (200 grams) for some weeks, monoand tri-chloracetic acids are formed (probably also some dichloracetic acid). Much acetic and phosphoric chlorides remained unchanged. When chloracetic acid and phosphorus pentachloride (1 mol. to 4 mols.) are heated for two days, perchlorethylene is formed, together with higher boiling substances, probably tetra- and penta-chlorethane. Phosphorus pentachloride and phenoxyacetic acid react violently when brought together in the cold. The product consists of trichlorophenoxyethylene (Abstr., 1886, 614) and a substance crystallising in rhombic prisms melting at 151-152°. The latter has the composition of a chlorophenoxyacetic acid.

N. H. M.

B-Dimethacrylic Acid. By D. USTINOFF (J. pr. Chem. [2], 34, 478-485).-The salts of B-dimethacrylic acid (Semljanitzin and Saytzeff, Abstr., 1879, 618) are described. The sodium salt, C,H,O2Na, forms white, opaque, effloresced crystals. The calcium salt, (C,H2O2)2Ca, forms bundles of long, silky crystals belonging to the rhombic system, soluble in water and alcohol. The barium salt, (C,H,O2),Ba + 2H2O, nodular groups of prismatic crystals. The zinc salt,

(C,H,O2)2Zn + 4H2O,

crystallises in rhombic plates. The copper salt, (C,H,O2)2Cu + 2H2O, crystallises in efflorescent rhombic plates. The lead salt, (C,H,O2),Pb + H2O, forms bundles of needles, and the silver salt, C,H,O,Ag, is a crystalline powder. When B-dimethylacrylic acid is treated in ethereal solution with bromine, it forms a dibromide, C,H,Br2O2; this is a crystalline substance melting at 105-106°. The salts and bromine compound of 3-dimethyacrylic acid distinguish it from its isomerides, angelic, methylcrotonic, and allylacetic acids.

H. K. T.

Acids from Drying Oil. By K. HAZURA (Monatsh. Chem., 7, 637-638). When linoleic acid is oxidised with potassium permanganate in alkaline solution, linusic acid, C18H3Ò, is formed. It crystallises in lustrous needles, very sparingly soluble in water, and melts at 188°.

The acid contained in hemp-oil yielded a tetrabromo-derivative melting at 114-115°, and a hexabromo-derivative melting at 177°; the latter compound is amorphous. The analyses of the two compounds make it probable that the formula of the original acid is C1H3O2, and not C16H2802. N. H. M.

Methoxydiallylacetic Acid and its Salts. By S. BARATAEFF (J. pr. Chem. [2], 35, 1-6).—Methoxydiallylacetic acid (Abstr., 1885, 512) is readily soluble in alcohol, ether, and hot water. The

ethyl salt boils at 214-216°. Sp. gr. = 0·96228 at 28° (water at 20° = 1). Determinations of the refractive power of the ethyl salt point, according to Brühl's law, to the presence of two double affinities; this was confirmed by the formation of a bromine-derivative, C1HO,Br1, by the action of bromine on the salt. Barium methoxydiallylacetate crystallises with 2 mols. H2O in needles, rather readily soluble in water; the calcium salt forms slender crystals, more sparingly soluble than the barium salt; the zinc salt crystallises in microscopic, slender needles, very soluble in water; the lead salt (with 63 mols. H2O) separates from its solution when slowly evaporated at 10°, in large, triclinic prisms, rather sparingly soluble in water, and more soluble in alcohol. The copper salt, with 1 mol. H2O, separates from the warm aqueous solution in bright green, oily drops, which solidify on cooling; the silver salt separates in thin threads, rather soluble in water.

N. H. M.

Oxalic Acid from the Residue of Spiritus Ætheris Nitrosi. By H. FRICKHINGER (Arch. Pharm. [3], 24, 1065-1068).-By taking alcohol of 0.812 sp. gr. instead of 0·832, as given in the German Pharmacopoeia, almost the whole of the liquid may be distilled over, and there is much less free acid to contend with in the distillate. The nitric acid is not sufficient in amount to completely oxidise all the products of the reaction. The residue from the first distillation, amounting to about 2 per cent. of the original charge, is wine-yellow, strongly acid, and has a specific gravity of 1·10. It contains no nitric acid, but, on the contrary, a large quantity of oxalic acid, which can be economically converted into ammonium oxalate. If this residue is poured into nitric acid of 1:35 sp. gr., and allowed to stand for some weeks, crystals of oxalic acid separate out from the grass-green liquid obtained. The mother-liquor becomes again colourless on warming for some time. The rectified ether is perfectly neutral in reaction; at first the sp. gr. of the distillate is 0835, then 0-840, 0.845, and 0850, at which point it remains until the rectification suddenly

ceases.

J. T.

Preparation of Ethyl Oxalate. By E. SCHATZKY (J. pr. Chem. [2], 34, 500-501).-A better yield of the oxalate is obtained by maintaining the mixture of oxalic acid and alcohol in ebullition for some hours, then distilling off any ethyl formate formed, adding more alcohol, and again boiling. By this means 56 03 per cent. of the theoretical yield is obtained. H. K. T.

Action of Ethyl Iodide and Zinc on Ethyl Malonate. By C. DAIMLER (Ber., 20, 203-204).—When a mixture of ethyl malonate (1 mol.) and ethyl iodide (2 mols.) is heated with zinc, ethane is evolved, and ethylic ethylmalonate is obtained; the yield amounts to 90 per cent. of that required by theory. The author finds that ethylmalonic acid yields two barium salts, one (C,H,O1),Ba + H2O, which crystallises in hemispherical aggregates, and is converted into barium butyrate at 100°, and a second, C,H,O,Ba + H2O, which forms slender, lustrous prisms, very sparingly soluble in water. When, in the above reaction, 4 mols. instead of 2 mols. of ethyl iodide are

employed, an almost quantitative yield of ethyl diethylmalonate is obtained. W. P. W.

Action of a Mixture of Allyl and Ethyl Iodides and Zinc on Ethyl Oxalate. By S. BARATAEFF (J. pr. Chem. [2], 35, 7—16). -A mixture of ethyl oxalate (1 mol.), allyl iodide (1 mol.), and ethyl iodide (2 mols.) was added by drops to finely granulated zinc in a retort kept cold by means of ice. The contents of the retort were left for 24 hours, and then heated in a water-bath for 10 hours. The product was then treated with sulphuric acid to dissolve the zinc oxide, and distilled. The oil so obtained was fractionally distilled, and was found to consist of a mixture of ethylic diethyloxalate and diallyloxalate. The reaction is analogous to that which takes place between allyl and ethyl iodide, zinc and ethyl formate (Kanounikoff and Saytzeff, this Journal, 1877, ii, 298). N. H. M.

Diallyloxalic Acid. By E. SCHATZKY (J. pr. Chem. [2], 34, 485 -500). The following data were obtained for the optical relations of diallyloxalic acid:

For a 7·08 per cent. solution in benzene at 18.6°—

D= 0·88981, na = 1·494830, ns = 1·151107, A = 1.475135.

[blocks in formation]

The ammonium, sodium, potassium, lithium, silver, calcium, barium, magnesium, lead, copper, cadmium, and zinc salts have been prepared. Ethyl diallyloxalate combines with bromine, forming a yellowishbrown liquid of the formula C10H16Bг.03.

Diallyloxalic acid when treated with bromine gave a neutral substance, crystallising in microscopic needles, insoluble in water, soluble in alcohol, ether, and benzene, and melting at 42-43°. The substance is scarcely acted on by sodium carbonate; with potassium hydroxide no definite results were obtained. It is probably a tribromolactone formed from the tetrabromodiallyloxalic acid by removal of hydrogen bromide. Diallyloxalic acid combines with hydrogen chloride, forming a thick liquid, OH·C(C,H,Cl)2COOH.

Diallyloxalic acid is converted by concentrated bydriodic acid into iododiallylacetic acid, from which diallylacetic acid can be obtained by means of sodium amalgam, hence diallyloxalic acid has the formula OH·C(C2H2)2COOH.

H. K. T.

Action of Ethyl Chloracetate and Zinc on Ethyl Oxalate. By R. FITTIG and C. DAIMLER (Ber., 20, 202—203).-When a mixture of ethyl oxalate (1 mol.) and ethyl chloracetate (2 mols.) is heated with

VOL. L'I.

26

zinc at 100° for several days, a dark-brown zinc compound is obtained, which is readily decomposed by water with formation of a bright yellow, amorphous substance, but when treated with dilute sulphuric acid, and extracted with ether, yields a thick oil, probably identical with Wislicenus' ethyl oxalacetate (this vol., p. 234), and a colourless, well crystallised compound, ethyl ketipate (ketone-adipate), C10H1406. This is a salt of a bibasic ketonic acid, whose constitution is probably either COOEt CH2 CO·CO·CH2·COOEt or COOET-CO-CH, CO-CH, COOEt. It melts at 76-77°, is decomposed by boiling water, and is readily soluble in ether, chloroform, alcohol, benzene, and carbon bisulphide. Ferric chloride colours the alcoholic solution an intense red. With phenylhydrazine, a compound, C,H,(N2C&H)2(COOEt)2, is obtained, crystallising from chloroform in yellow needles. Aqueous barium and calcium hydroxides precipitate white insoluble compounds of the formula C10H12O,Ba(or Ca) + H2O. By the action of bromine, according to the conditions of the experiment, there is obtained either a tetrabromo-substitution-derivative, CO2Br.(COOEt)2, crystallising in yellow prisms, or a partially saponified compound of the formula CO2H2Br2(COOH)COOEt, forming colourless crystals.

Ketipic acid is a white powder, insoluble in ordinary solvents, and is very unstable. When heated, it decomposes into carbonic anhydride and a yellow liquid, which boils at 78-79°, and has an odour resembling that of quinone. W. P. W.

Nitration of a-Thiophenic Acid. By M. RÖMER (Ber., 20, 116 -118).—When a-thiophenic acid is gradually added to concentrated nitric acid at 50°, nitro-a-thiophenic acid, NO2 C,SH2 COOH, is formed. This acid exists in two modifications, the one crystallising in long, thin, colourless needles melting at 145-146°, the other in compact crystals melting at 125°. From an aqueous solution, the needles crystallise out first, and afterwards the compact variety. By recrystallisation, the latter modification is always partially, sometimes wholly, converted into the needles, whilst when placed under water, the needles are gradually changed into the compact variety. This behaviour resembles that of dinitrothiophen. With a trace of soda, both modifications of the acid give a magenta-red coloration which is destroyed by excess of alkali. The silver salt forms colourless needles; the ethyl salt colourless needles, melting at 70-71°, and subliming unchanged; the copper salt forms bluish-green hydrated prisms.

L. T. T. Constitution of Benzene. By A. BAEYER (Ber., 19, 1797-1810; see also this vol., p. 370), by J. THOMSEN (Ber., 19, 2944-2950), and by A. LADENBURG (Ber., 20, 62-65).-Theoretical papers: an account of the arguments brought forward will be found in the present number of the Transactions (A. K. Miller, Trans., 1887, 208-215).

Chlorination of Toluene. By E. SEELIG (Annalen, 237, 129– 181). The trichlorotoluenes have already been described by the author (Abstr., 1885, 769). Pure orthochlorotoluene can be obtained

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