GB800857A - Process for the manufacture of amino-triaryl-carbinols and triaryl-methane dyestuffs - Google Patents

Abstract

Triarylcarbinols free from amino groups and containing in at least one of the aryl residues a halogen atom parato the carbinol carbon, are obtained by conversion of triaryl-halogen methanes which are obtained by condensing aryl trihalogen methanes with aryl compounds in the molecular ratio 1 : 2 in the presence of aluminium chloride or iron chloride and hydrogen chloride, which last may be formed from the aluminium or iron chloride by addition of a little water or by exposure to air, either the aryl-trihalogen-methane containing halogen para to the trihalomethyl methyl group, or the aryl compound containing halogen para to hydrogen or both. The temperature may be 80-100- C., and conversion of the triaryl-halogen-methane to the triarylcarbinol may be effected by pouring into water or on to ice. Examples describe the preparation of (1) tri-(p-chlorphenyl) carbinol from p-chlorbenzotrichloride and chlorbenzene; (2) p-chlorphenyl - di - (p - bromophenyl)-carbinol from p-chlorbenzotrichloride and bromobenzene; (3) phenyl-di-p-bromo- or chlorophenyl)-carbinol from benzotrichloride and bromobenzene or chlorbenzene; (4) diphenyl-p-chlorphenyl-carbinol from p-chlorbenzotrichloride and benzene; (5) p-chlorphenyl-di-(p-methylphenyl)-carbinol from p-chlorbenzotrichloride and toluene.ALSO:Triarylmethane dye bases, which are amino- or arylamino-triaryl-carbinols, are obtained by reacting with ammonia or a primary arylamine a triarylcarbinol which is free from amino groups and in which at least one aryl residue contains a halogen atom para to the carbinol carbon atom (see Group IV (b)). The reaction may be conducted in aqueous medium at e.g. 140-220 DEG C., in presence of copper or a copper compound. The products are often resinous, but may be worked up by dissolution in moderately concentrated sulphuric acid and reprecitation with ammonia, or resinification may be avoided by reacting in presence of e.g. kieselguhr or active carbon. The products are converted by acids to the dyestuffs, which inter alia dye polyacrylonitrile fibres, and reserve wool fibres. They may be used in aqueous solution or dispersion. In examples, aqueous ammonia is reacted with (1) tri-(p-chlorophenyl) carbinol, (2) p - chlorphenyl - di - (p - bromophenyl) - carbinol, (3) phenyl - di - (p - chlorphenyl) carbinol, (4) phenyl - di - (p - bromophenyl) carbinol, (5) diphenyl - p - chlorphenyl-carbinol, (6) p - chlorphenyl - di - (p - methylphenyl) carbinol. Also in examples, (7) tri-(p-chlorphenyl) carbinol is reacted with aniline or a -naphthylamine. A dyeing example with an acetic acid bath and polyacrylonitrile fibres is given.