Patent GB-440113-A (GB)
Title: Process for the manufacture of azodyestuffs
IPC: C09B29/033
Filed: 1934-06-20
Abstract: Azo dyes; azo dyes, forming upon the material; cellulose esters, dyeing.--Azo dyes are manufactured by coupling a diazotized 2-aminothiazole compound with an amine coupling in p-position to the amino group, including such amines in which the nitrogen atom of the amino group is part of a heterocyclic ring. The products are suitable for dyeing and printing cellulose esters, e.g. cellulose acetate artificial silk.  The dyestuffs containing a primary amino group may be diazotized on the fibre and developed.  Examples describe the manufacture of the following dyestuffs: (1) 6-methoxy-2-aminobenzothiazole --> dihydroxyethyl-m-toluidine; the product dyes cellulose acetate pink shades; (2) 6-methoxy-2-aminobenzothiazole --> dihydroxyethylaniline; the product dyes cellulose acetate red shades; the dihydroxyethylaniline may be replaced by methylhydroxyethylaniline, ethylhydroxyethylaniline, diethylaniline, dimethylaniline, cresidine CH3 : NH2 : OCH3 = 1 : 2 : 4), xylidine (CH3 : CH3 : NH2 = 1 : 4 : 2), dihydroxyethylcresidine, dihydroxyethyl - m - chloraniline or dihydroxyethylaminohydroquinone dimethyl ether, and the 6 - methoxy - 2 - aminobenzothiazole by 6 - ethoxy-, 6 - chloro-, 6 - methyl-, 4 - chloro-6-methyl- or 6-nitro-2-aminobenzothiazole; (3) 4 - methyl - 2 - aminothiazole --> dihydroxyethylaniline; the product dyes cellulose acetate yellowish-red shades; (4) the 2-aminothiazole obtained from tetrahydro-b -naphthylamine (by transforming it into the corresponding thiourea and oxidizing this with sulphuryl chloride) --> methylhydroxyethylaniline; the product dyes cellulose acetate bluish-red shades; (5) 2-aminobenzothiazole --> 1-amino-3-methyl-6-methoxybenzene; the product dyes cellulose acetate scarlet shades, which may be diazotized on the fibre and developed with 2 : 3-hydroxynaphthoic acid, yielding a blue; (6) 6-methoxy-2-aminobenzothiazole --> 1 - hydroxyethylamino - 5-hydroxynaphthalene; the product dyes cellulose acetate blue shades; the 6-methoxy-2-aminobenzothiazole may be replaced by 2-aminobenzothiazole itself or by other substitution products thereof, and the 1-hydroxyethylamino-5-hydroxynaphthalene by 1-amino-5-hydroxynaphthalene, 1-(g -chloro-2-hydroxypropyl) - amino - 5 - hydroxynaphthalene or 1 - dimethylamino - 5 - hydroxynaphthalene ; (7) 6 - methoxy - 2 - aminobenzothiazole --> py - 3 - hydroxytetrahydro - 7 - hydroxynaphthoquinoline; the product dyes cellulose acetate bluish-green shades; the 6-methoxy-2-aminobenzothiazole may be replaced by 2-aminobenzothiazole; (8) 6-methoxy-2-aminobenzothiazole --> py-tetrahydro-3-hydroxynaphthoquinoline; the product dyes cellulose acetate reddish-blue shades; (9) 6-methoxy-2-aminobenzothiazole --> py-3-hydroxytetrahydro-7-hydroxynaphthoquinoline; the product dyes cellulose acetate bluish-green shades; (10) 6 - methoxy - 2 - aminobenzothiazole --> N-phenylpiperazine; the product dyes cellulose acetate red shades; (11) 6-methoxy-2-aminobenzothiazole --> py - tetrahydro - 1 - butyl - 3-hydroxy-7-methylquinoline; the product dyes cellulose acetate reddish-violet shades; (12) 6 - methoxy - 2 - aminobenzothiazole --> 1-hydroxyethyl-3-hydroxytetrahydro-7-hydroxynaphthoquinoline; the product dyes cellulose acetate bluish-green shades; the 6-methoxy-2-aminobenzothiazole may be replaced by 2-aminobenzothiazole or its 6-methyl derivative. Dihydroxyethylcresidine, dihydroxyethyl - m - chloraniline and dihydroxyethylaminohydroquinone dimethyl ether are obtained by heating in water one molecular proportion of cresidine, m-chloraniline and aminohydroquinone dimethyl ether respectively with two molecular proportions of glycol chlorhydrin in the presence of prepared chalk.  4 - Chloro - 6 - methyl - 2 - aminobenzothiazole is obtained by transforming 2-chloro-4-methylaniline hydrochloride by means of ammonium thiocyanate into the corresponding thiourea and oxidizing this with sulphuryl chloride.  1 - Hydroxyethylamino - 5 - hydroxynaphthalene is obtained by heating in water 1-amino-5-naphthol with glycol chlorhydrin in the presence of prepared chalk.  1 - (g  - Chloro - 2 - hydroxypropyl) - amino - 5 - hydroxynaphthalene is obtained by boiling in methyl alcohol 1-amino-5-naphthol and epichlorhydrin.  py - 3 - Hydroxytetrahydro - 7 - hydroxynaphthoquinoline is obtained by boiling in butyl alcohol 1-amino-5-naphthol and epichlorhydrin.  py - Tetrahydro - 3 - hydroxynaphthoquinoline hydrochloride is obtained by boiling in water a -naphthylamine and epichlorhydrin.  py - Tetrahydro - 1 - butyl - 3 - hydroxy - 7 - methylquinoline is obtained by heating 1-butylamino-3-methylbenzene with epichlorhydrin in chlorobenzene.  1 - Hydroxyethyl - 3 - hydroxytetrahydro - 7 - hydroxynaphthoquinoline is obtained by heating in water py-3-hydroxytetrahydro-7-hydroxynaphthoquinoline with glycol chlorhydrin in the presence of prepared chalk.