GB565697A - Manufacture of azo-dyestuffs and intermediate products thereof - Google Patents

Abstract

Dyestuff intermediates are obtained by esterifying with sulphochloroacetic acid a compound of the general formula <FORM:0565697/IV/1> wherein x represents H or alkyl, including substituted alkyl. Azo dyes are obtained by coupling the products so obtained with a diazotized amine or by esterifying with sulphochroacetic acid the alcoholic hydroxy group in a compound of the general formula <FORM:0565697/IV/2> wherein R represents the residue of the diazotized amine. The products, in the form of their alkali or ammonium salts, are applicable for dyeing cellulose acetate materials and, in certain cases, for dyeing animal fibres, e.g. wool or silk. Specified diazo components are aniline, toluidines, anisidines, 2-, 3- or 4-nitroanilines, 4 - nitro - 2 - chloroaniline, 4 - nitro - 2 - methoxyaniline, 4 - nitroaniline - 2 - methylsulphone, 4 - nitro - 2 - cyanoaniline, 4 - nitro - 2 : 6-dichloroaniline, 2 : 4-dinitroaniline, 2 : 4-dinitro-6 - cyano or 6-halogenanilines, 2 : 4 dinitroaniline-6-methylsulphone, 4-nitro-2-cyano-6-halogenanilines and 4-nitroaniline-2-sulphonic acid. Specified coupling components, of which the alcoholic hydroxy group is esterified before or after the coupling, are N-methyl-, ethyl,-propyl-, isopropyl-, butyl-, isobutyl-, amyl- or cetyl-N-b -hydroxyethyl-aniline, N-b -methoxyethyl-N-b -hydroxyethyl-aniline, N-methyl-N-g -hydroxypropyl-aniline, N-ethyl-N-b -hydroxy-g -chloropropyl-aniline, 3-methyl-N-propyl- or butyl-N-b -hydroxyethyl-aniline, 3-methyl-N-di-(b -hydroxyethyl)-aniline, 3-acetylamino-6-methoxy-N-ethyl- or butyl-N-b -hydroxyethylaniline and 5-methyl-2-methoxy-N-propyl- or butyl - N - b - hydroxyethyl-aniline. Examples relate to the esterification in toluene with sulphochloroacetic acid of (1) N-ethyl-N-b -hydroxyethyl-aniline, the toluene being distilled off and the product being coupled in aqueous solution with diazotized aniline, 4-chloroaniline, 2- or 4-nitroaniline, 4-nitro-2-chloroaniline or 4 - nitro - 2 - cyanoaniline; (2) 3 - methyl - N - di - (b - hydroxyethyl) - aniline or 3 - methyl p - N - mono - (b - hydroxyethyl) - aniline, the toluene being separated by addition of water and the product being coupled in aqueous solution with diazotized 4-nitro-2-cyanoaniline or its 6-chloro derivative; (3) 3-methyl-N-di-(b -hydroxyethyl)-aniline, the toluene being distilled off and the product being coupled in aqueous solution with diazotized 2 : 4-dinitro-6-cyanoaniline; (4) the azo dyestuff 4-nitroaniline --> N-ethyl-N-b -hydroxyethyl-aniline. Specification 517,918 is referred to.