Basic dyestuffs

摘要

The invention relates to dyestuffs of the formula wherein R denotes an alkyl, cycloalkyl, aralkyl or aryl radical, R1 denotes a hydrogen atom or a cycloalkyl, aryl or cyano group, R2 denotes a hydrogen atom or a cyano, carboxylic acid ester, or carboxylic acid amide group, R3 denotes an alkyl, cycloalkyl, aralkyl or aryl radical, A represents the atoms necessary to complete an unsaturated heterocyclic 5- or 6-membered ring, to which benzene rings may be fused, and X denotes an anion, wherein the aromatic rings B and C and said benzene rings fused on A and R, R1, R2, R3 and A may contain substituents other than sulphonic acid and carboxylic acid groups. In examples A completes an indolenine, dihydro-(1,2) - quinoxalone - (3), dihydro - (3,4) - pyrimidone-(2), benzimidazole, benzothiazole, benzoxazole, perimidine and 1,3,4-triazole nucleus which may be substituted by alkoxy, acetamido, aralkyl, cyclohexyl, aryl, Cl, Br, carbomethoxy and methylsulphonamido groups. Rings B and C may be substituted by Cl, Br, alkoxy, alkyl or dimethylamino groups. Alkyl groups R3 may be substituted by acetyl or ethoxy groups. The dyes are prepared by the usual condensation reactions and also quaternization of the dye bases with compounds of formula R3X.ALSO:The compound of formula is prepared by reacting the compound of formula with cyanogen chloride followed by reaction of the product with dimethyl formamide in the presence of phosphorus oxychloride.