Patent GB-569771-A (GB)
Title: Disazo dyestuffs
IPC: C09B33/10
Filed: 1943-12-02
Abstract: Disazo dyes are made by coupling, in acid medium, one molecular proportion of a diazotised primary arylamine of the benzene or naphthalene series which contains at least one halogen atom or one of the groups carboalkoxy, carboxy and carbamyl, wherein the hydroxy of the carboxy and the hydrogen of the carbamyl group may optionally be replaced by hydrocarbon residues or substituted hydrocarbon residues, but which is devoid of nitro, acidylamino, aminosulphonyl, sulpho and sulphone groups, with 1-amino-8-naphthol-3.6- or 4.6-disulphonic acid, and coupling, in alkaline medium, with the resulting monoazo compound, one molecular proportion of a diazotised amine of the formula X-CO-NY-R-NH2, wherein R represents a p-phenylene residue which may be substituted by, e.g. methyl or methoxy, but which contains no amyloxy or sulphonic acid substituent, X represents a monochloro- or monobromo-methyl group and Y represents an alkyl group of less than 7 carbon atoms or a cycloalkyl group.  In examples, the following dyes are made: o-chloroaniline --> (acid) H-acid (alkaline) \sM 4-amino-1-N-cyclohexyl-o -chloroacetanilide, m-aminoacetophenone --> (acid) H-acid (alkaline) \sM 4-amino-1-N-cyclohexyl-o -chloro- or bromo-acetanilide, 4-aminobenz-N-ethylanilide or m-aminobenzoic acid --> (acid) H-acid (alkaline) \sM 4-amino-1-N-cyclohexyl - o  - chloroacetanilide, n - butyl, n-aminobenzoate --> (acid) H-acid (alkaline) \sM 4-amino-1-N-cyclohexyl-o -chloroacetanilide, 4-aminobenz-N-benzylanilide --> (acid) H-acid (alkaline) \sM 4-amino-1-N-ethyl-o -chloro- or bromo-acetanilide or 4-amino-1-N-n-butyl - o  - chloroacetanilide and 2.5 - dichloroaniline --> (acid) K-acid (alkaline) \sM 4-amino - 1 - N - cyclohexyl - o  - chloroacetanilide.  Additional diazo components specified are: p-aminobenzoic acid, 4-chloro-2-aminobenzoic acid, m- or p-chloroaniline, o-, m- or p-bromoaniline, 2.4-dichloroaniline, 4-chloro-2-aminoanisole, 5-chloro-2-aminotoluene, 3- or 4-aminobenzanilide, 3 - aminobenz - N - ethylanilide, 4-aminobenz-m-toluidide, N -3-aminobenz-N-b -hydroxyethylanilide, 3- or 4-aminobenzoyldiphenylamine, 4 - aminobenz - N - cyclohexyl - anilide, N-4-aminobenzoyl-N-ethyl-21-aminotoluene, n - butyl, p - aminobenzoate, 3- or 4-aminobenzoyl - N - ethyl -a  - naphthylamine, 4-amino-N.N-dimethylbenzamide and p-amino-aceto- or benzo-phenone; 4-amino-1-N-isopropyl- or (p - methylcyclohexyl) - o  - chloroacetanilide and 5 - amino - 2 - N - cyclohexyl-o -chloroacet-toluidide.  The dyes are suitable for dyeing animal fibres, wool and silk being specified.  The Provisional Specification describes also the production of dyes wherein R, in the above formula, represents a m- or p-phenylene residue which may be substituted by, e.g. methyl, methoxy or (except para to the amino group) sulphonic acid groups, but which contains no amyloxy substituent, X represents a monochloro- or monobromo-alkyl radical of not more than three carbon atoms and Y represents hydrogen, alkyl of less than seven carbon atoms, cycloalkyl, aralkyl, alkoxyalkyl or aryl, and wherein the middle component may be any 1-amino-8-naphthol sulphonic acid having the 2- and 7-positions free.  N - 3 - Aminobenz - N - b  - hydroxyethylanilide is obtained by reacting m-nitrobenzoyl chloride with N-b -hydroxyethylaniline and reducing the nitro group. 4-Aminobenz-N-benzylanilide is obtained by reacting N-benzylaniline with p-nitrobenzyl chloride and reducing the nitro group.  N - 4 - Aminobenzoyl - N - ethyl - 21 - aminotoluene is obtained by reacting N-ethyl-o-toluidine with p-nitrobenzoyl chloride and reducing the nitro group.  4 - Amino - N : N - dimethylbenzamide is obtained by reacting p-nitrobenzyl chloride with dimethylamine and reducing the nitro group.