GB300178A - - Google Patents

Abstract

300,178. I. G. Farbenindustrie Akt.- Ges. Nov. 7, 1927, [Convention date]. Azine dyes.-Safranime dyestuffs which dye wool from an acid bath blue to violet shades are prepared by oxidation of a 4-acidylamino-3<1>- amino- or 4-nitro-3<1>-amino-diphenylamine-2-sulphonic acid or homologue or derivative thereof with a p-phenylenediamine or a derivative thereof. The acidylamino group in the product may be saponified and the nitro group may be reduced, e.g. by means of zinc and acetic acid or by alkaline hydrosulphite, the resulting leuco compound then being oxidized. The benzene nuclei, other than the azonium benzine nucleus, may contain alkyl, halogen or sulphonic substituents. The amino groups may be substituted by alkyl and aryl groups. According to examples. the following pairs of components are condensed by oxidation. : (1) 4-acetamino - 3<1>- -amino-4<1>- methyldiphenylamine-2-sulphonic acid and 4- ammo-4<1>-methoxy-diphenylamine-2-sulphonic acid or 4-aminodiethylaniline-3-sulphonic acid; (2) 4- nitro - 3<1>-dimethylaminodiphenylamino-2-sulphonic acid and 4-aminodiphenylamine-2-sulphonic acid or 4-amino-4<1>-methoxydiphenylamine-2-sulphonic acid. 4-Nitro-3<1>-aminodiphenylamine-2-sulphonic acid and the corresponding 3<1>-alkylamino-, and 31-arylamino-derivatives may be obtained by condensing 1 : 3-phenylenediamine or its asymmetric N-alkyl or aryl derivatives with 4-nitrochlorbenzene-2- sulphonic acid. 4-Acidylamino - 3<1>- aminodiphenylamine-2-sulnhonic acids and derivatives thereof may be obtained by reduction, and partial acidylation, of the corresponding nitro compounds. 4-Acetylamino - 3<1>-amino-4<1>-methyldiphenylamine - 2 - sulphonic acid (example 1) may thus be obtained by condensing 4-nitrochlorbenzene-2-sulphonic acid with 4-methyl-1 3-phenylenediamine, reducing and partially acetylating. 4 - Amino-4<1>-methoxydiphenylamine-2-sulphonic acid (example 1) is prepared by condensing 1- methoxy-4-aminobenzene with 4-nitro-1-chlorbenzene-2-sulphonic acid, in the presence of an acid binding agent, and reducing the 4-nitro-4<1>- methoxydiphenylamine-2-sulpbonic acid with iron and dilute hydrochloric acid. The Specification as open to inspection under Sect. 91 (3) (a) comprises also the use of 4-nitro- 3<1> - aralkylaminodiphenylamine-2-sulphonic acids as starting material. This subject-matter does not appear in the Specification as accepted.