GB111321A - Manufacture of New Intermediate Products suitable for the Manufacture of Colouring Matters. - Google Patents

Abstract

111,321. Levinstein, H., and Morgan, G. T. Nov. 17, 1916. p-Nitro-N-methylformanilide, its homologues, and substitution products (other than nitro derivatives) are prepared by nitrating, at a moderately low temperature, N-methylformanilide, or its homologues or substitution products having a free p-position to the amino group, such as halogen or alkyloxy derivatives or o- or m-N-methylformyltoluidide. The parent N-methylformyl bases are prepared either by formylating the N-methyl bases by boiling with formic acid, or by methylating, e.g. with dimethylsulphate, The N-formyl base or the crude N-formyl methyl base prepared from crude N-methyl base containing some non- methvlated base. p-Amino-N-methylformanilide, its homologues, and substitution products are prepared by reducing the above-described nitro compounds with such reducing agents as do not eliminate the formyl group, preferably iron borings in water slightly acidified with formic or acetic acid. Monoazo dyes are prepared by coupling the diazo compounds of p-amino-N - methylformanilide, its homologues, or substitution products with phenols, naphthols, aminophenols, aminonaphthols, or their sulphonic or carboxylic acids; other dyes are obtained by hydrolyzing the formyl group of these dyes.