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acid, melting at 59°, by the action of sodium phenylmercaptide. The chlorocrotonic acid melting at 94° yields an isomeric thiophenylcrotonic acid which melts at 158° with evolution of carbonic anhydride. It is much more soluble in alcohol than the isomeride of higher melting point, and the barium salt crystallises with 1 mol. H2O. The two thioethylerotonic acids corresponding to the thiophenylcrotonic acids melt at 91-92° (from chlorocrotonic acid melting at 59°) and 113— 115° respectively.

N. H. M.

Croton Oil. By KOBERT (Chem. Zeit., 11, 416).-Senier found that English pressed croton oil dissolved or was miscible with alcohol in any proportion not exceeding the volume of the oil employed, but that if an excess of alcohol was used, some of the oil was rendered insoluble. By this means he separated croton oil into two distinct parts possessing different physiological properties, the part soluble in alcohol possessing the well-known vesicating but no purgative property, whilst the insoluble portion was found to possess the purgative but not the vesicating property (Abstr., 1884, 909, 947).

This separation by means of alcohol, the present author contends, is incorrect. The chief element in the solubility is the age of the oil, and there are, moreover, some kinds of croton oil soluble in every proportion of alcohol.

He further states that the purgative and vesicating properties of croton oil are due solely to the presence of crotonolic acid which exists free and combined as a glyceride in all croton oils. A process is given for the preparation of the pure acid from croton oil.

J. P. L. Acids from Drying Oils. By K. HAZURA and A. FRIEDRICH (Monatsh. Chem., 8, 156-164; compare this vol., p. 359).—When the acids from poppy and nut oils (30 grams) are saponified with 36 c.c. of a solution of potassium hydroxide (sp. gr. = 1·27), the product dissolved in 3 litres of water, and oxidised with a solution of potassium permanganate (30 grams) in water (3 litres), they both yield 4 to 5 grams of sativic acid, CH2O(OH), melting at 161-162°. When the two acids are treated with bromine they yield the same bromoderivatives as does the acid from hemp oil: a compound melting at 175°, and the compound CHBrO, melting at 112-115°. Sativic acid is also formed when linoleic acid is oxidised in dilute solution; when a more concentrated solution is oxidised, sativic acid and linusic arid, C18H36Os, are formed. The latter crystallises from water in microscopic needles melting at 203°; it is a monobasic acid. The acetyl-derivative, C1sHO(OAc), is a thick, yellow oil. When linoleic acid in concentrated alkaline solution is oxidised with finely-powdered potassium permanganate, azelaïc acid, C,H,O,, is formed. Bromine acts on linoleic acid with formation of a compound, C18HBrO2, identical with the tetrabromide of the dibromo-acid from hemp oil.

The authors think it probable that linoleic acid contains an unsaturated acid of the series C,H2_6O2, which yields linusic acid when oxidised. The presence of such an acid would also account for the fact that linoleic acid dries more readily than the others.

N. H. M.

Acid from Hemp-seed Oil. By K. HAZURA (Monatsh. Chem., 8, 147-155).-The tetrabromide of the acid from hemp-seed oil, C18H32 Br4O2, is formed together with the tetrabromide of the dibromoacid, C18H30BrO2, when 50 grams of the acid dissolved in glacial acetic acid is treated with 21 grams of bromine. It crystallises in white, lustrous plates which melt at 114-115°, and dissolve readily in glacial acetic acid, chloroform, benzene, ether, and alcohol; it is insoluble in water. The salts, with the exception of the alkali salts, are insoluble in water and in ether. The compound C1HBrO, is white, melts at 177°, is very sparingly soluble in alcohol, glacial acetic acid, benzene, &c., insoluble in water. When the acid C18H32Br4O2 is reduced with tin and hydrochloric acid, the bromine is eliminated but not replaced by hydrogen. These results point to the formula CHO2 for the acid from hemp oil. Sativic acid is shown to be tetrahydroxystearic acid, C18H32O2(OH). Tetracetylsativic acid, C18H32O(OAc)4, prepared by boiling sativic acid with acetic anhydride, forms a light-yellow oil insoluble in water, soluble in alcohol, ether, light petroleum, &c.

N. H. M.

Ethyl Cyanacetoacetate. By A. HALLER and A. HELD (Compt. rend., 104, 1627-1629).-The ethyl cyanacetoacetate obtained by James (Trans., 1887, 287) by the action of potassium cyanide on ethyl chloracetoacetate is identical with the compound obtained by the authors (Abstr., 1882, 1280) by the action of cyanogen chloride on ethyl acetosodacetate. The formation of this compound from ethyl chloracetoacetate shows that the latter has the constitution

CHACCI COOEt,

and not CH2CI-CO-CH, COOEt, as supposed by James.

A much higher yield can be obtained by James's method than is stated in his paper.

C. H. B.

Preparation of Levulinic Acid. By P. RISCHBIETH (Ber., 20, 1773-1775). The following method is recommended as avoiding the use of the large quantities of ether required in the usual process. 3 kilos. of powdered potato-starch are added to 3 litres of hydrochloric acid of sp. gr. 1.1, contained in a pan on the water-bath, the mixture being constantly stirred until all is dissolved to a thin syrup. This is then transferred to two capacious flasks provided with reflux tubes, and heated for 20 hours in a vigorously boiling water-bath. The magma obtained is pressed in order to separate humous substances, and the liquid is again heated for some hours on the water-bath in a flask connected to a water-pump, when water, hydrochloric acid, and formic acid distil. The residual syrup (consisting mainly of levulinic acid) is then transferred to a capacious fractioning flask, and heated in an oil-bath under reduced pressure, when nearly pure levulinic acid passes over at 135-150° under 60 mm. pressure. The distillate solidifies completely, either spontaneously or when a fragment of crystallised levulinic acid is added. The acid is further purified, with but slight loss, by redistillation in a vacuum. The yields is 13 to 14 per cent. of the starch employed. A. J. G.

Salts of Lævulinic Acid. By J. BLOCK and B. TOLLENS (Annalen, 238, 301-302).—Barium lævulinate, (CH4O3)2Ba + 2H2O, is slowly deposited from concentrated solutions in needle-shaped crystals, freely soluble in water. Strontium lævulinate, (C5H7O3)2Sr + 2H2O, crystallises in prisms. It is also freely soluble in water.

W. C. W.

Propylxanthic Acid. By A. SCALA (Gazzetta, 17, 78–82).— Potassium propyl xanthate, SK CS.OPr, crystallises in yellow, silky needles, very soluble in water, sparingly soluble in alcohol and ether. Its copper salt is an orange-yellow, the silver salt a pale yellow, the lead and mercury salts white precipitates. On adding hydrochloric acid to a solution of the potassium salt, the free acid separates as a pale yellow, insoluble oil, rapidly decomposing into its constituents. Propyldioxythiocarbonate, OPr CS S2 CS OPr, prepared from iodine and potassium propyl xanthate, is a pale yellow oil of peculiar odour. With alcoholic ammonia it yields a crystalline precipitate, probably the amide of the acid. Methyl propyl xanthate, SMe CS-OPr, is a pale yellow oil of a nauseous, garlic-like odour, boiling at 202-203-5°; the ethyl salt, of similar appearance and odour even more disagreeable, boils at 2156-217-6°. Determinations of the vapour-densities of these compounds are given. V. H. V.

Potassium Manganic Oxalate. By F. KEHRMANN (Ber., 20, 1594-1596).-Potassium manganic oxalate, K ̧Mn2(C2O1)。 + 6H2O, is always obtained as an intermediate product when solutions of potassium permanganate are reduced with oxalic acid in the cold, but in the presence of an excess of oxalic acid the reduction goes further, and the method is unsuitable for the isolation of the compound. It can, however, be separated if the calculated quantities of finely powdered hydrogen potassium oxalate and oxalic acid are gradually added to a mixture of manganic hydroxide and snow or finely powdered ice, and the deep purple-red solution, after rapid filtration, is mixed with alcohol until crystallisation commences, and then allowed to remain for 1 to 2 hours in a mixture of ice and salt. It crystallises in almost black, monoclinic prisms, transmitting light of a red colour at the edges, and is isomorphous with the corresponding iron salt; the two compounds show the same habitus, and when mixed in suitable proportions give mixed crystals on the addition of alcohol to the saturated aqueous solution. The salt is tolerably stable at the ordinary temperature and in the absence of light, but sunlight and heat decompose it with the evolution of carbonic anhydride. In water just slightly warm the salt dissolves at first without alteration, but soon decomposes with the evolution of much carbonic anhydride. The barium salt is obtained in dark red, sparingly soluble scales on the addition of barium chloride to a cold solution of the potassium salt.

W. P. W.

Addition of Ethyl Malonate to Compounds containing Doubly-linked Carbon-atoms. By L. CLAISEN (J. pr. Chem. [2], 35, 413–415.)-A. Michael has described as a new reaction the addition of ethyl malonate or ethyl acetoacetate to substances with

doubly-linked carbon-atoms (this vol., p. 672). It is pointed out that the action of the aldehydes on ethyl malonate and ethyl acetoacetate, described by Komnenos and Claisen, Perkin, Junr., and by Hantzsch, is exactly similar, the first product of the action being a non-saturated compound, which then again enters into reaction exactly as described by Michael (compare Abstr., 1884, 422, 443, 444, 445). H. B.

a-Amidoisosuccinic Acid. By G. KOERNER and A. MENOZZI (Gazzetta, 17, 104-109).-a-Amidoisosuccinic or a-isoaspartic acid, NH, CMe(COOH)2, is formed on warming a mixture of pyruvic and hydrocyanic acids under pressure; the product is treated with alcoholic ammonia, the nitrite formed is best saponified by barium hydrate, and the barium salt decomposed by sulphuric acid. The free acid crystallises in transparent prisms, readily decomposed, when heated at 100°, into a-alanine and carbonic anhydride. In conformity with the hypothesis of Van t'Hoff, the acid is optically inactive. The salts of the alkali and alkaline earth metals crystallise in needles, soluble in cold, more so in hot water; the copper salt forms sparingly soluble, blue needles, and the silver salt a white, flocculent precipitate. The hydrochloride, sulphate, and nitrate crystallise in transparent prisms.

V. H. V.

Butyl Sebacate. By G. GEHRING (Compt. rend., 104, 1289-1290). Butyl sebacate is obtained by the action of hydrogen chloride on a mixture of normal butyl alcohol and sebacic acid heated at 150°. It is a colourless liquid, with an agreeable, aromatic odour and a burning taste. It is insoluble in water; is miscible with alcohol in all proportions, and somewhat less miscible with ether; sp. gr. at 0° 0·9417; at 15° 0·9329. It boils at 344-345° without decomposition. Small quantities on a glass rod burn with a flame with a deep blue centre, but the liquid cannot be ignited on the surface by a Bunsen burner.

Butyl sebacate is decomposed by sulphuric acid in the cold, with evolution of sulphurous anhydride. With ammonia it yields white microscopic needles of sebacamide, CH10(CONH2)2, and when treated with chlorine in sunlight a solid is formed, which is probably C10H1604 (CC19)2.

C. H. B.

Perchloramyl Perchlorosebacate and Perchlorobutyl Perchlorosebacate. By G. GEHRING (Compt. rend., 104, 1624-1625).— When dry chlorine is passed into a flask containing isoamyl sebacate exposed to sunlight, the chlorine is somewhat rapidly absorbed with considerable development of heat. When the energy of the reaction diminishes the flask is gradually heated, the temperature being eventually raised to 230°. The substance becomes solid, but continues to absorb chlorine, and again becomes liquid. After about four days, long, white needles separate, and these are removed from time to time and dried over lime and sulphuric acid in a vacuum. They are purified by sublimation and washing with water and alcohol. The compound thus obtained is perchloramyl perchlorsebacate, (CsCl)2C10C8O. It forms long, semitransparent, rhombic prisms, which melt at 179°, sublime readily, and when exposed to moist air become yellow,

VOL. LII.

3 h

resinous, and acid, and eventually volatilise. It has an aromatic smell, but no taste, is of a waxy consistency and cannot be powdered. It is heavier than water, and is volatile in water vapour. It will not dissolve in water, but is slightly soluble in alcohol and very soluble in ether, chloroform, benzene, light petroleum, and terebenthene.

Perchlorobutyl perchlorosebacate, (C.Cl,)2C10ClO4, is obtained in a similar manner, but the action is still more rapid. It forms snowwhite, hexagonal prisms, which melt at 172° and boil at 200°. Its other properties resemble those of the preceding compound, but after washing with much water it becomes hard and brittle.

C. H. B.

Reciprocal Transformation of the Optically Active Asparagines. By A. PIUTTI (Gazzetta, 17, 126-128).-The inactive aspartic acid, when converted into the ethereal salt, and then heated with alcoholic ammonia, yields a crystalline mixture of the optically active asparagines. The transformation is somewhat similar to that effected by Jungfleisch in the case of tartaric acid. The monethyl aspartate is best obtained by decomposing the copper salt with hydrogen sulphide; it crystallises in micaceous laminæ, melting at 200° with decomposition.

V. H. V.

Alkyl-compounds of Bismuth. By A. MARQUARDT (Ber., 20, 1516-1523. Compare Michaelis and Michaelis and Polis, this vol., p. 368). These compounds are prepared by adding an ethereal solution of bismuth bromide (2 mols.) to a solution of zinc alkyl in ether. The ether is afterwards distilled off in a current of carbonic anhydride, and the residue treated with aqueous soda in an atmosphere of hydrogen when the bismuth alkyl separates.

Trimethylbismuthine, BiMe,, is a clear, mobile, strongly refractive liquid, having a very disagreeable, irritating_odour, sp. gr. = 2·30 at 18°. It fumes in air but does not inflame. It boils at 110°, dissolves readily in ether, alcohol, glacial acetic acid, and light petroleum; it is insoluble in water. When heated in air it explodes violently. It distils readily with steam, but decomposes when long in contact with water. Strong hydrochloric acid decomposes it with formation of bismuth chloride and methane.

Dimethylbismuthine chloride, BiMe,Cl, separates in flakes when chlorine is passed through a solution of trimethylbismuthine in light petroleum, kept cold by means of ice and salt, and is purified by washing with a mixture of alcohol and much ether. It melts at 116° and dissolves readily in alcohol; it is insoluble in ether.

Dimethylbismuthine bromide, BiMe,Br, forms a white powder, readily soluble in alcohol, insoluble in ether. It inflames when warmed.

Methylbismuthine dichloride, BiMeCl2, is obtained by the action of trimethylbismuthine on bismuth chloride dissolved in glacial acetic acid. It separates in yellowish-white plates, melts at 242°, and dissolves sparingly in alcohol and glacial acetic acid, and is insoluble in ether. Methylbismuthine dibromide, BiMe Br2, forms a yellow powder melt. ing at 214; it is insoluble in ether, sparingly soluble in alcohol, benzene, &c. The diiodide, BiMela, is prepared by heating methyl

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