Patent GB-546665-A (GB)
Title: Manufacture of azo dyestuffs
IPC: C09B29/08
Filed: 1940-11-22
Abstract: 546,665. Dyes. DU PONT DE NEMOURS & CO., E. I. Nov. 22, 1940, No. 16774. [Classes 2 (iii)] and 15 (ii)] Water-soluble monoazo dyes, suitable for dyeing or printing cellulose acetate textile materials dischargeable blue shades, fast to light, to washing, and to gas fumes are obtained by coupling diazotized 2 : 4-dinitro-aniline or its 6-chloro- or 6-bromo-derivative with a 2-alkoxy-5-acylamino-N-alkyl-N -sulphatoalkyl - aniline, the alkyl and alkoxy groups containing from 1 to 4 carbon atoms, the acylamino group being of the general formula-NH.CO.R, wherein R represents alkyl of 1 to 4 carbon atoms and the sulphatoalkyl group is of the general formula -CnH 2 n.O.SO 3 M, wherein n represents 2 or 3 and M represents H, NH 4  or an alkali metal. Examples (1) to (3) relate to the production of the dyestuffs, (1) 2:4- dinitroaniline# 2 -methoxy - 5 -acetylamino - N - ethyl-N-sulphatoethyl-aniline, (2) 6-chloro- or bromo-2 : 4-dinitroaniline# 2-methoxy- or ethoxy-5-acetyl- or propyl-amino-N-ethyl-N- sulphatoethyl-aniline. Other specified coupling components are 2-methoxy-5-acetylamino-N- butyl - N - sulphatoethyl - aniline, 2 - methoxy - 5 - valerylamino - N - ethyl - N - sulphato - ethyl - aniline, 2 - methoxy - 5 - acetylamino - N - ethyl - N - sulphatopropyl - aniline, 2 - butyloxy - 5 - acetylamino - N - ethyl - N - sulphatoethyl - aniline and 2 - methoxy - 5 - acetylamino - N - methyl - N - sulphatoethyl - aniline. Specifications 181,750, 237,739, [both in Class 2 (iii)], 430,079 and 431,564 are referred to. 2 - Alkoxy - 5 - acylamino - N - alkyl N - sulphatoalkyl-anilines are obtained by reaction of the appropriate 4-alkoxyaniline with the appropriate fatty acid halide or anhydride, nitrating the resulting acylamino compound and reducing the nitro group, treating the resulting 2-alkoxy-5-acylamino-aniline with the appropriate alkyl halide or sulphate and alkylene oxide or halohydrin and treating the product with sulphuric and chlorosulphonic acid. Alternatively, the appropriate 2-alkoxy- 5-nitroaniline may be treated with the alkyl halide and alkylene oxide or halohydrin, the nitro group reduced and the resulting amino group acylated and the product treated with sulphuric or chlorosulphonic acid. The Specification as open to inspection under Sect. 91 comprises also (a) the use as diazo components of 2 : 4-dinitro-aniline, further substituted by trifluoromethyl, methyl, methoxy, ethoxy, cyano, CO.Alkyl or SO 2 - Alkyl wherein the alkyl group contains 1 or 2 carbon atoms, or nitro, additional specified diazo components being 6-trifluoromethyl-2 : 4. dinitro-aniline, 2-amino-3 : 5-dinitro-aceto- or propiono-phenone, 2-amino-3 : 5-dinitrophenylmethyl or -ethyl sulphone, 6-cyano-2 : 4-dinitroaniline, 6-methyl-2 : 4-dinitro-aniline, 6- methoxy- or ethoxy-2 : 4-dinitro-aniline and 2 : 4 : 6-trinitro-aniline, (b) the use as coupling component of the corresponding compounds in which the alkyl groups and the alkoxy group in 2-position may be replaced by hydroxyethyl or in which n may represent 1, additional specified coupling components being 2 - hydroxyethyl - 5 - acetylamino - N - hydroxyethyl-N-sulphatoethyl-aniline and 2-methoxy- 5 - lactylamino - N - ethyl - N - sulphatoethylaniline. This subject-matter does not appear in the Specification as accepted.