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product is converted into the silver salt, and from this by treatment with hydrogen sulphide the hydro-acid is obtained. It crystallises in yellowish-white probably monoclinic tables, melts at 162° (corr.), is readily soluble in water, less so in ether, and shows all the properties of a hydro-acid. Thus it reduces an ammoniacal silver solution, and when heated with sulphuric acid decomposes into thiophenic acid and carbonic oxide. The barium salt, C.SH(COO), Ba, crystallises in small lustrous scales; and the silver salt, C.SH. (COOAg)2, is a white powder. When an alcoholic solution of the hydro-acid is saturated with hydrogen chloride, methyltetrahydrothiophendicarboxylate,


is obtained as an oil which cannot be distilled and does not solidify. a-Thiophencarboxylic acid, on reduction, yields an acid which crystallises in colourless needles, melts at about 48°, is readily soluble in water, and reduces ammoniacal silver solution. W. P. W.

Synthetical Investigations in the Thiophen Series. By F. ERNST (Ber., 19, 3278-3282).-The author has endeavoured to effect the synthesis of an anthracene of the thiophen series, but without success. The following compounds prepared in the course of the work are described :-

Orthotoluyl thienyl ketone, C,H,Me CO C,SH,, obtained by the action of orthotoluic chloride on thiophen in the presence of aluminium chloride, is a colourless oil; when boiled for some time it loses water, and is completely resinified. The acetoxime is a non-volatile oil.

Phenyl thiotolyl ketone, CH, CO·C,SH,Me, is formed by treating coal-tar thiotolen with benzoic chloride in the presence of aluminium chloride. The ketone is a syrup, and on long boiling loses water and is resinified. The acetoxime was prepared, but is not described. When thienylglyoxylic acid is reduced with sodium amalgam in the cold, thienylglycollic acid, C.SH, CH(OH)·COOH, is obtained. crystallises in white needles, melts at 115°, is readily soluble in water, alcohol, ether and benzene, and decomposes on distillation. Oxidation with manganese dioxide converts it into thiophenaldehyde; the yield, however, is small. The barium and calcium salts are readily soluble in water; the silver salt is obtained as a white precipitate.

Thienylacetic acid, C,SH, CH, COOH, is obtained by boiling thienylglycolic acid with hydriodic acid and amorphous phosphorus. It forms colourless crystals, melts at 76°, and is soluble in hot water, alcohol and ether. The barium salt forms white crystals readily soluble in water; the silver salt is obtained as a white precipitate.

W. P. W.

Synthesis of a-Phenylthiophen. By W. KUES and C. PAAL (Ber., 19, 3141-3144).-Following out their previous work (Abstr., 1886, 536), the authors find that if B-benzopropionic or ẞ-benzoisosuccinic acid is substituted for levulinic acid, similar reactions occur. In these cases, however, the intermediate hydroxy-product appears to be less stable than thiotolen, and traces only were obtained. The main product was a-phenylthiophen, C,SH,Ph [Ph = 1]. With the

isosuccinic acid, evolution of carbonic anhydride and formation of the ketonic acid takes place before the reaction occurs. a-Phenylthiophen crystallises in plates melting at 40-41°, and is soluble in carbon bisulphide and the usual organic solvents, insoluble in water. It is volatile in steam, and has the characteristic odour of diphenyl. It dissolves in cold concentrated sulphuric acid, and is reprecipitated unchanged on the addition of water. It shows the indophenin reaction, but does not give any characteristic coloration with Laubenheimer's reaction. When added to cold bromine, it forms parabromophenyltribromothiophen, which crystallises in white needles melting at 145-146°, sparingly soluble in alcohol and acetic acid, easily in carbon bisulphide and benzene. It is a very stable compound, may be heated with dilute nitric acid at 180° without change, and is only oxidised by continued boiling with chromic acid in acetic solution, and then forms parabromobenzoic acid. Attempts made to form a phenyltribromothiophen were unsuccessful. A mixture of a compound crystallising in white needles melting at 55-56° (probably a phenyldibromothiophen) with a very soluble bromo-derivative, melting at 33-36°, was produced.

L. T. T.

Pentathiophen-group. By K. KREKELER (Ber., 19, 3266-3274). -The lactone of a-methylhydroxyglutaric acid (Block and Tollens, Abstr., 1886, 533) is prepared by slowly adding 100 grams of levulic acid to 100 grams of potassium cyanide, finely rubbed with 10 grams of water, the whole being well cooled. It is then kept for 24 hours in a loosely-closed vessel, treated with the necessary amount of fuming hydrochloric acid, and left for three or four days. It is extracted with ether, saponified by heating for one hour on a waterbath with fuming hydrochloric acid, and again extracted with ether. It is purified by means of the barium salt. The hydroxy-acid is converted into methylglutaric acid by boiling with twice its volume of hydriodic acid and amorphous phosphorus.


B-Methylpentathiophen, CH, CHCHS, is obtained by distilling 5 grams of sodium methylglutarate (dried at 160°) with 10 grams of phosphorus trisulphide at 180-250°. From 550 grams of sodium salt, 20 grams of crude oil were obtained; this is boiled for some hours with strong potash solution, distilled, the oily distillate treated with a little dilute permanganate solution, and then re-distilled over sodium. It is a colourless, very refractive oil, boiling at 134°, and has the odour of pure xylene. Sp. gr. = 0·9938 at 19° (water at 19° 1). When the solution of the substance in glacial acetic acid is treated with a solution of isatin in the same solvent, and then with sulphuric acid (keeping it cold), an intense dark-green coloration is produced. When poured into water, a green flaky precipitate is formed, soluble in ether. Laubenheimer's reaction yields a dark violet coloration in sulphuric acid.

B-Methylacetopentathienone, C,SH,MeAc, is prepared by treating a solution of 1 part of B-methylpentathiënone in 10 parts of light petroleum with the calculated amount of acetic chloride, and adding aluminium chloride until the evolution of hydrogen chloride ceases.

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It is purified by steam distillation. It is a clear heavy oil, having an odour resembling that of acetophenone; it boils at 233–235° (uncorr.). The ketoxime, C,SH,Me CMe: N.OH, was prepared by Peter's method (Abstr., 1885, 141). It crystallises from ether in long, branched needles melting at 68°; it dissolves readily in alcohol and ether.

When ẞ-methylpentathiophen is treated with 0.3 per cent. alkaline potassium permanganate solution, the oxidation takes place very quickly with formation of acetic and oxalic acids.

When air saturated with methylpentathiophen is passed through fuming nitric acid a nitro-compound is formed. The alcoholic solution of the latter, treated with a drop of potash solution, acquires an intense violet-red colour which disappears in a few minutes.

N. H. M.

Action of Light on Nitrobenzene in Alcoholic Solution. By G. CIAMICIAN and P. SILBER (Ber., 19, 2899-2900).—In continuation of experiments on the transformation of quinone to quinol on exposing its alcoholic solution to sunlight (Abstr., 1886, 695), the authors have studied the chemical change induced in nitrobenzene under similar conditions. Among the products obtained, were aldehyde, aniline, and a quinoline base, probably quinaldine.

V. H. V. Orthoethyltoluene: Oxidation of Orthodialkyl-derivatives of Benzene with Potassium Permanganate. By A. CLAUS and E. PIESZCEK (Ber., 19, 3083—3092).—The common statement that ortho-xylene, on oxidation with potassium permanganate, yields first orthotoluic acid and then phthalic acid is incorrect, nothing but phthalic acid being formed; not even a trace of orthotoluic acid is detectable. By the oxidation of orthoethyltoluene with potassium permanganate, orthotoluic, phthalic, and terephthalic acids were obtained according to the temperature and concentration of the solutions. At 100°, in alkaline solution, total combustion took place. The results obtained with cymene completely corresponded with those obtained with orthoethyltoluene.

Bromorthoethyltoluene is a colourless oil boiling at 220-221° (uncorr.); when heated with nitric acid, sp. gr. 1-2, in sealed tubes at 190-200°, it is oxidised to a bromorthotoluic acid, [Me: COOH : Br= 1:2:4]. This forms snow-like flocks composed of slender needles, melts at 118° (uncorr.), is sparingly soluble in cold water, readily soluble in alcohol, ether, and hot water, and yields readily soluble crystalline salts with the alkali metals, and with barium and calcium. It is not identical with the acid described by Jacobsen (Abstr., 1885, 143), to which he assigned the same constitution; the authors consider it more probable that his acid has the constitution [1: 3: 4].

By the action of nitric acid on orthoethyltoluene in the cold, a mono- and dinitro-derivative are formed; the latter is a pale-yellow oil, and does not solidify at 0o.

Orthoethyltoluene-B-sulphonic acid, CH,MeEt SO2H [1: 2: 4], is obtained, together with the a-acid which has not yet been investigated, by the action of pyrosulphuric acid on orthoethyltoluene; it forms a deliquescent, colourless, crystalline mass. The potassium, sodium,

barium, calcium, lead, copper, and silver salts are described. The chloride is a yellow oil, the amide forms a yellow, buttery mass.

A. J. G.

Oxidation of the Homologues of Phenol. By B. HEYMANN and W. KÖNIGS (Ber., 19, 3304-3315).-Continuing their experiments (Abstr., 1886, 542), the authors find that the oxidation of the homologues of phenol can readily be effected if the phenols are converted into the corresponding dipotassium phosphates; these double salts are prepared by heating the phenols (1 mol.) with phosphoric oxychloride (1 mol.), carefully adding water to the cooled product, extracting the resulting chlorinated phosphorus compounds with ether, and decomposing them with potassium carbonate. The double phosphates are then oxidised with alkaline potassium permanganate, acidified with hydro. chloric acid, and boiled for a short time. The double phosphates of the phenols are found to be more stable than the corresponding double sulphates, and a better yield is obtained when the former are oxidised. By this method, orthocresol is readily oxidised to salicylic acid.


Thymol treated with potassium pyrosulphate yields a double sulphate, CH,MePra SO,K [Me: SO,K: Pr 1:3: 4], crystallising in fine silky fibres, which decomposes readily on keeping or when heated on a water-bath, although it is stable in alkaline solution; it is sparingly soluble in 50 per cent. alcohol, readily soluble in absolute alcohol and in water. When the double sulphate or double phosphate is oxidised, thymohydroxycumic acid, COOH-C,H,POH [COOH OH: Pr 1:34] (Abstr., 1879, 158), is obtained.


Carvacryl potassium sulphate, C,H,MePr.SO,K, crystallises in silvery scales, decomposes very readily on keeping or on gently heating, is stable in alkaline solution, and is soluble in water and absolute alcohol. Carvacryl dipotassium phosphate, CH,MePrPO.K2 +5H2O, crystallises in large, silvery silvery lamina decomposing at 100°, readily soluble in water and in absolute alcohol. Some tricarvacryl phosphate was formed in the preparation of the double salt. When oxidised with permanganate, both the double sulphate and double phosphate yield parahydroxyisopropylsalicylic acid, COOH CH3(OH) CMe2 OH [COOH: OH: CMe, OH = 1:2:4], which crystallises from water in large, flat needles, and in slender, concentrically grouped needles from chloroform. The acid melts at 130-135°; a more exact determination was not possible owing to the tendency to dehydrate and form parapropenylsalicylic acid. Hydroxyisopropylsalicylic acid is sparingly soluble in cold water, readily soluble in chloroform, alcohol and ether, insoluble in carbon bisulphide, and gives with ferric chloride an intense reddish-violet coloration. The silver salt, C10H1O.Ag, crystallises in colourless needles; the copper salt, (CHO),Cu + H2O, crystallises in green prisms which do not lose their colour on drying; it is sparingly soluble in water. When heated with concentrated hydriodic acid and amorphous phosphorus, the acid is reduced to isohydroxycumic acid, OH-C,H,Pr-COOH (Abstr., 1878, 731).

Parapropenylsalicylic acid,

COÓH·C2H2(OH)·CMe: CH2 [COOH : OH: (CMe: CH2) = 1 : 2 : 4],


is readily obtained from hydroxyisopropylsalicylic acid by gently warming it on a water-bath with dilute hydrochloric acid. crystallises in slender needles, melts at 145-146°, is sparingly soluble in cold water, readily soluble in alcohol, ether and boiling carbon bisulphide, and gives an intense reddish-violet coloration with ferric chloride. It is volatile with steam, and when heated at 150° sublimes with slight decomposition. The silver salt, CH,O,Ag, forms a crystalline powder, very sparingly soluble in water; the copper salt, (CoH9O3)2Cu + 2H2O, forms small, green crystals insoluble in water, the anhydrous salt is not hygroscopic. By reduction with sodium amalgam in the cold, an acid agreeing in its properties with Jacobsen's isohydroxycumic acid (loc. cit.) was obtained; the melting point, however, was 96-97° instead of 93-94°.

When a boiling aqueous solution of hydroxyisopropylsalicylic acid is treated with an equal volume of concentrated hydrochloric acid, a polymeride, propenylsalicylic acid, (C10H10O3), is obtained in small, white crystals which melt at 230° with evolution of carbonic anhydride. It is insoluble in water and carbon bisulphide, soluble in hot acetic acid, alcohol and ether, and the alcoholic solution is coloured an intense reddish-violet with ferric chloride. The acid is not volatile with steam nor is it reduced by sodium amalgam.

Attempts to oxidise the ethyl, isopropyl, isobutyl, and amyl potassium sulphates led to no result.

W. P. W.

Action of Sodium Methoxide on Bromobenzene. By F. BLAU (Monatsh. Chem., 7, 621-636).-When bromobenzene is heated with sodium methoxide in sealed tubes, anisoïl is formed together with phenol; the sodium methoxide thus acting like a mixture of the alcohol and alkali: a considerable proportion of the bromobenzene is unaltered. The reactions with di- and symmetrical tri-bromobenzenes are precisely analogous; thus from the former are obtained bromanisoïl, dimethylquinol, and bromophenol; from the latter a dibromophenol and dibromanisoil. The dibromophenol forms white crystals melting at 76.5°, readily soluble in alcohol and ether, sparingly in water and petroleum; on fusion with alkali, it yields phloroglucol; it is, therefore, a symmetrical compound. V. H. V.

Bisulphides with Mixed Organic Radicles. By R. OTTO and A. RÖSSING (Ber., 19, 3132-3138).-Hitherto no organic bisulphides with mixed radicles have been obtained. The authors find that such compounds are formed when a mixture of two mercaptans are treated with bromine, and that the reactions take place the more readily the more closely allied are the radicles of the reacting mercaptans. The reaction is R·SH+R'SH + Br2 = 2HBr + R·S¿·R'.

Phenyl paratolyl bisulphide, CH, S2 Ph, is obtained by dissolving molecular proportions of phenyl and paratolyl hydrosulphides in ten times their volume of ether, and slowly adding a molecular proportion of bromine. This substance is a thick, pale-yellow oil. It is insoluble in water, miscible in all proportions with alcohol and ether, has an odour somewhat resembling that of tolyl hydrosulphide, is heavier than water, and scarcely volatile in steam. When heated with alcohol and zinc-dust, it is decomposed into the corresponding zinc mercaptides.

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