GB915139A - Basic heterocyclic monoazo dyestuffs - Google Patents

Abstract

The invention comprises dyes of formula <FORM:0915139/IV (b)/1> where R is the residue of a 5- or 6-membered ring, R3 is H or alkyl, cycloalkyl, aralkyl or aryl, R4 is alkyl, cycloalkyl, aralkyl or aryl, X is an acid residue, A an aryl or hetero residue and n is 1, 2 or 3. The dyes, except where R3 is H and R4 is aryl, may be made by treating a compound of formula <FORM:0915139/IV (b)/2> where Z is an acylamino group, with quaternising agents, and hydrolysing to give an amino group. The starting dyes are made by diazotising appropriate aromatic and heterocyclic primary amines and coupling with the required active methyl- or methylene-hetero-cyclic compound. Representative of specified amines are 4-amino-acetanilide, 1-amino-3,4-diacetylaminobenzene, 1-amino-5- acetyl-amino-naphthalene, 3-aminopropionic acid-anilide, 4-aminobenzanilide and 4-acetylbenz-idine. Examples of indicated heterocyclic compounds are 1,3,3-trialkyl-2-methylene-in-dolines, 1-alkyl-2-methylenebenzthiazoles, 1-alkyl-2-methylenebenzoxyazoles and 1-alkyl-2-methylene-dihydroquinolines, which may contain substituents in the aryl nucleus. Dyes may also be made by reacting compounds of formula <FORM:0915139/IV (b)/3> where Y is O, or the residue of an aromatic amine, with compounds of formula H2N-N(R4)-A-(Z)n, and the resulting hydrazones are converted into salts, if desired, or treated, in the form of the free bases, with quaternising agents and Z is hydrolysed to a free amino group. Representative of specified compounds used in this preparation are quinoline-, pyridine-benzthiazole- and 1-methyl-benzimidazole- 2-aldehydes and azo-methines made from 1,2-dimethyl-pyridi-nium or quinaldinium iodide or 1,2-dimethyl-benzthiazolium methosulphate with nitroso-dimethylaniline. Representative of specified hydrazine compounds are N-4-acetylamino-phenyl-N-methyl- and N-4-acetylaminophenyl-N-benzyl-hydrazine. The dyes colour textiles, paper and leather, and, if free from carboxylic or sulphonic acid groups, colour polyacrylonitrile. Examples are provided of the preparation of the dyes and their use in dyeing polyacrylonitrile in red and blue shades. Specification 875,995 is referred to.