Page images
[merged small][ocr errors][merged small]

Displacement of the Amido-group in Aromatic Compounds by Hydrothionyl and Oxysulphuryl. By P. KLASON (Ber., 20, 349-350). When diazosulphonic acids are treated in small quantities with warm alcoholic solution of potassium sulphide, nitrogen is evolved, and the diazo-group is displaced by SH; in this way thiocresolsulphonic acid was prepared. The sulphonic acids can be readily purified by precipitating with an ammoniacal solution of lead acetate, and decomposing the lead salt by means of hydrogen sulphide.

When the thiophenolsulphonic acids are treated with potassium permanganate in the cold, toluenedisulphonic acids are formed in which oxysulphuryl has taken the place occupied by the amido-group in the original amido-acid.

The method above described can be employed for introducing selenium and probably also tellurium into aromatic compounds.

N. H. M.

Halogen-derivatives of Azobenzene and Hydrazobenzene. By J. V. JANOVSKY and L. ERB (Ber., 20, 357-362; compare Abstr., 1886, 1024).-Parabromazobenzene is the chief product obtained by brominating azobenzene dissolved in glacial acetic acid. It melts at 82°, and can be sublimed; it dissolves readily in alcohol, ether, and acetone, less in light petroleum. When the alcoholic solution is treated with ammonia and then with hydrogen sulphide, a hydrazobromo-compound is formed which crystallises in lustrous plates, melting at about 115°.

Dinitromonobromazobenzene, C12H, (NO2)2BrN2, and nitroparabromazobenzene, C12H8 (NO2) BrN2, are obtained by nitrating parabromazobenzene; the former crystallises in orange-red, sparingly soluble needles; the latter forms yellow needles readily soluble in alcohol. When parabromazobenzene is dissolved in fuming sulphuric acid at 140°, a sulphonic acid is formed identical with the parabromoparasulphonic acid of azobenzene previously described (Sitzungsber. Akad. Wissen., 1884, 647).

Metabromazobenzene is prepared from the product obtained by the action of bromine on azobenzene by extracting the precipitated bromides with a little 80 per cent. alcohol. It forms yellowish-green, lustrous plates, readily soluble in alcohol, ether, and acetone; it melts at 53-56°. Metabromazobenzeneparasulphonic acid is obtained by heating a solution of metabromazobenzene in fuming sulphuric acid (5 parts) at 160°. It crystallises in plates with a golden lustre. The potassium salt crystallises in yellow, lustrous, microscopic needles. The sodium salt is sparingly soluble.

Nitrazobenzene, NPh: N-CH, NO2, is obtained by dissolving azobenzene (20 grams) in 100 c.c. of glacial acetic acid, heating at 100°, and adding 25 c.c. of nitric acid (sp. gr. 1·51). The product is filtered and purified by crystallising from a mixture of acetone and alcohol. It forms orange-yellow, microscopic needles, readily soluble in alcohol,

&c. It melts at 122-123°. When the alcoholic solution is boiled with alkali, it acquires a splendid emerald colour. The sulphonic acid forms hygroscopic needles; the solution of the acid gives with potassium carbonate a purple-red precipitate consisting of woolly needles; with sodium salts a green, and with silver salts a red precipitate.

Nitrazoxybenzene is prepared by nitrating azobenzene at 75°. It crystallises from alcohol, ether, chloroform, and acetone in red plates, melting at 127°.

Hexazoxybenzene, CH,NO, is formed when orthonitrazobenzene or nitrazoxybenzene (m. p. 127°) is reduced with sodium amalgam. It is almost insoluble in ether, alcohol, and acetone, readily in boiling benzene, toluene, and xylene, separating therefrom in orange-coloured plates. Warm fuming sulphuric acid dissolves it with a violet-blue colour.

N. H. M.

Direct Substitution Products of Parazotoluene; Hydrazobromobenzenes, and Hydrazobromotoluenes. By J. V. JANOVSKY and L. ERB (Ber., 20, 362-364).-When 10 grams of parazotoluene dissolved in 200 c.c. of glacial acetic acid is gradually treated with 15 c.c. of nitric acid (sp. gr. 1·5), and the product precipitated with water and dissolved in hot alcohol, two nitro-compounds are obtained. The one crystallises in orange-yellow, monoclinic needles melting at 114°, the other separates from the mother-liquor as an oil which gradually crystallises. When parazotoluene is treated directly with fuming nitric acid in the cold, two nitro-products are also formed, one of which is sparingly soluble in alcohol and acetone, and forms honeycoloured monoclinic crystals melting at 185-187°. It is a dinitrazotoluene, and is possibly identical with that described by Petrieff (Jahresber., 1873), to which, however, the melting point 110° is ascribed. No mononitro-compound melting at 76° (Petrieff, loc. cit.) could be obtained.

By the action of bromine on a boiling solution of azotoluene, a bromide crystallising in large, ruby-coloured prisms, melting at 138.5°, is formed; it is probably identical with Petrieff's monobromide (m. p. 136°). The mother-liquor from the bromide yielded a second bromide melting at 115°.

Parabromhydrazobenzene, NH Ph NH-C,H,Br, is prepared by reducing parabromazobenzene with alcoholic solution of hydrogen ammonium sulphide. It crystallises from dilute alcohol in lustrous scales which melt at 115°. It is very stable in the air, and only becomes slightly coloured in four to six weeks. When treated with sulphuric acid, and the sulphate thus obtained decomposed with ammonia, a monobromobenzidine is obtained which crystallises in silvery plates. Dibromohydrazobenzene melting at 82° was obtained from diortho


Bromoparahydrazotoluene was prepared in a similar manner from bromoparazotoluene; it melts at 117°. N. H. M.

Action of Acetone on Paramidoazobenzene. By C. ENGLER and C. SCHESTOPAL (Ber., 20, 480-482).—When acetone (1 mol.) is

heated with paramidoazobenzene hydrochloride (2 mols.) in sealed tubes at 150-160° for two to three days, methane is formed together with a solid condensation product from which hydrochloric acid extracts a base, CHIN3; this is probably a quinoline or benzidine derivative, and after fractional precipitation with aqueous potash and distillation in a vacuum is found in the fraction boiling at 280°. It crystallises in bright yellow needles, melts at 204-205°, and is soluble in alcohol and ether; the aqueous solutions of its salts show a strong blue fluorescence. The sulphate, C17H15N3, H2SO1, crystallises from aqueous alcohol in small, monoclinic prisms, and is very soluble in water; the chromate, C1H15N3,H,Cr2O,, forms orange-yellow, crystalline aggregates; and the platinochloride, C17H15N3,H2PtCle, crystallises in golden-yellow, flat needles sparingly soluble in cold water.

When reduced with tin and hydrochloric acid, a well-crystallised stannochloride of a base is obtained; this base crystallises in brilliant white needles, melts at 185°, dissolves readily in alcohol and ether, and yields well-crystallised salts. W. P. W.

Action of Phenol on Diazoamidobenzene. By K. HEUMANN and L. OECONOMIDES (Ber., 20, 372-373).—When diazoamidobenzene is heated on a water-bath with phenol, parahydroxyazobenzene is formed together with aniline. Resorcinol, and a- and ẞ-naphthol react in a similar manner. N. H. M.

Constitution of Safranines. By A. BERNTHSEN (Ber., 20, 179180). The constitution previously suggested (this vol., p. 139) for the safranines is supported by the explanation of the constitution of toluylene-red (p. 139). The author considers the unsymmetrical formula proposed by Witt and by Nietzki (this vol., p. 250) as the most probable.

N. H. M.

Manufacture of Methylene-blue. By O. MÜHLHÄUSER (Dingl. polyt. J., 262, 371–379).—For the production of methylene-blue on a large scale two processes are in use: (1.) Oxidation of dimethylparaphenylenediamine in acid solution, in presence of hydrogen sulphide (Caro's method); (2.) Oxidation of a base containing sulphur, obtained by the action of hydrogen sulphide on nitrosodimethylaniline dissolved in strong sulphuric acid (Oehler's process). The author describes in detail the manufacture of methylene-blue by the "soda waste" and "zinc sulphide" processes. The former comprises the following operations:-(1.) Preparation of a solution of nitrosodimethylaniline by treating dimethylaniline with hydrochloric acid, and nitrating the hydrochloride thus obtained. (2.) Treatment of the nitrosodimethylaniline with soda waste in order to reduce the nitroso-compound to an amine. (3.) Oxidation with ferric chloride. (4.) Extraction of the raw colour with salt and zinc chloride solution. (5.) Filtration.

The zinc sulphide process.-When hydrogen sulphide is passed into sulphuric acid of 40-50° B., sulphur is deposited and sulphurous anhydride evolved thus: H2SO, + H2S = SO2 + S + 2H2O. On bringing the sulphurous anhydride into contact with hydrogen

sulphide further precipitation of sulphur takes place according to the following equation: SO2 + 2H2S = 2H2O + 3S. When these reactions occur in the presence of nitrosodimethylaniline sulphate a colourless base containing sulphur is obtained, yielding a blue dye on oxidation. The methylene-blue obtained in this manner is said to be purer and stronger in tinctorial power than that yielded by the soda waste process. D. B.


Thiophen-green. By L. E. LEVI (Ber., 20, 513-517).-Tetramethyldiamidodiphenylthienylmethane, C,SH, CH(CH, NMe2)2, leuco-base of thiophen-green, is obtained by heating a mixture of thiophenaldehyde (1 part) and dimethylaniline (2 parts) with a small quantity of alcohol at 100° for six hours, and gradually adding three to four parts of zinc chloride. The base crystallises in compact needles, melts at 92-93°, and is insoluble in water, readily soluble in ether, benzene, toluene, and alcohol; the alcoholic solution very quickly becomes coloured green on exposure to the air. The platinochloride has the formula C2H2N2S,H,PtCl,; the picrate,


forms yellowish-green needles, melts at about 208°, and is sparingly soluble in cold water, readily soluble in alcohol, ether, &c.; the methiodide, CHaN,S,2MeI, crystallises from alcohol and water in white scales, and melts at 210-212°.

When the leuco-base is oxidised, preferably with manganese dioxide and dilute sulphuric acid, thiophen-green, C,SH, C(CH, NMe2), OH, is obtained as a dark-brown, uncrystallisable oil, insoluble in water, but soluble in alcohol, benzene, chloroform, and, when recently prepared, in ether; it cannot be distilled. Thiophen-green forms salts with the elimination of the elements of 1 mol. of water. The zinc salt, 3(CH2N2S), ZnCl2 + 2H2O, crystallises in scales showing a beautiful coppery lustre, and is readily soluble in all ordinary solvents; the solution in water is coloured a deep bluish-green, which becomes reddish-yellow on adding an acid. The colour imparted to silk and wool very nearly resembles that produced by benzaldehyde-green, but is somewhat more yellow. The picrate,


forms scales showing a coppery lustre, and is very sparingly soluble in water; the sulphate, C2H2N2S, H2SO4, crystallises in beautiful scales, readily soluble in water; and the oxalate,

2(C2H2N2S),3H¿C2O + 2H2O,

crystallises in scales showing a metallic lustre, is readily soluble in water, alcohol, &c., and decomposes very readily.

W. P. W.

Action of Phosphorus Pentachloride on Acetanilide. By A. MICHAEL (J. pr. Chem. 35, 207-208).-When phosphorus pentachloride is allowed to act on acetanilide at moderate temperatures, compounds very different in composition to the unstable chloroderivatives described by Gerhardt and by Wallach are obtained.

Thus, when a mixture of acetanilide (1 mol.) and phosphorus pentachloride (3 mols.), after the first reaction is over, is allowed to remain at the ordinary temperature until evolution of hydrogen chloride has practically ceased, then heated at 100° to complete the reaction, and poured into water, a compound, C,H,Cl2N2, is formed, which crystallises in large, white, monoclinic prisms, melts at 116.5-117°, is insoluble in water, soluble in alcohol, and shows both acid and basic properties. If, instead of completing the reaction at 100°, the mixture is allowed to remain in the cold for some time longer, and then poured into water, long, citron-yellow needles of a compound C38H38 Cl,N, are obtained. This melts at 227-229°, is soluble in alcohol, and shows both acid and basic properties. Two other compounds are also formed in this reaction, one of which crystallises in large tables, whilst the other is a thick liquid which only becomes solid after long standing.

The author finds that acetamide, when treated with 2 mols. of phosphorus pentachloride and subsequently with water, yields a compound in the form of a thick liquid. W. Þ. W.

Action of Hydroxylamine and Phenylhydrazine on Dialdehydes and Ketones. By F. MÜNCHMEYER (Ber., 20, 507-513).— Isophthalaldehyde reacts with hydroxylamine hydrochloride and soda to form the aldoxime CH(CH: NOH), = [1 : 3]; this crystallises in lustrous, white scales, melts at 211-212°, and is soluble in alcohol and ether. When treated with an excess of acetic chloride, isophthalaldoxime yields metadicyanobenzene; the methyl-derivative, CH(CH NOMe), crystallises in colourless needles melting at 77°, the ethyl-derivative in small needles melting at 165°.

Orthophthalaldehyde (which, according to a foot-note by V. Meyer, has been recently obtained by Faust, and will shortly be described), when heated with hydroxylamine hydrochloride and soda, yields orthophthalaldoxime, CH(CH: NOH), [1:2], it crystallises in small needles, melts at 245°, and is soluble in alcohol.

Tetramethyldiamidobenzophenone, although it reacts with hydroxylamine hydrochloride (Abstr., 1886, 877), does not yield a hydrazide when treated either with phenylhydrazine or its hydrochloride; further investigation of the action of these reagents on amidophenones shows that this behaviour is exceptional. When ß-dinitrobenzophenone is heated with hydroxylamine hydrochloride and soda, the oxime is obtained in small, golden-yellow needles melting at 205207°; and by treatment with phenylhydrazine hydrochloride the ketone yields a hydrazide, (C,H,NO2),Č : N·NHPh, this is a red powder melting at 219-220°, and is soluble in acetic acid, sparingly soluble in hot alcohol. B-Diamidobenzophenone under these conditions yields a crystalline oxime melting at 177-178°, and a hydrazide, (NH2·CH ̧),C : N2HPh, in the form of yellow needles melting at 183°. Also, when similarly treated, paramidoacetophenone is converted into an oxime crystallising in small needles which melt at 147-148°; and the hydrochloride of a hydrazide, NH2 C&HCMe: N,HPh, HCl, which is crystalline, and evolves gas when heated at 205-207°. W. P. W.

« PreviousContinue »