GB480486A - Process for the manufacture for sulfanilic acid amides which exert a strong bactericidal action - Google Patents

Abstract

Aminoanilides of sulphanilic acid or of its N-alkyl derivatives are prepared by any of the following processes: (a) an acylsulphanilic halide is condensed with a diamine, a monoacyldiamine, or a nitroamine of the benzene series, the nitro group, if present, is reduced, and the acyl group(s) removed, the last two operations being effected in either order; (b) sulphanilic acid anilide or an acyl derivative thereof is nitrated, the nitro group is reduced, and the acyl group, if present, is removed; (c) an acylsulphanilic amide is condensed, in the presence of a copper catalyst, with a nuclearly halogenated acylaniline or with a halogennitrobenzene, the nitro group, if present, is reduced, and the acyl group(s) removed, the last two operations being effected in either order; (d) a p-halogenbenzenesulphonic acid aminoanilide, acylaminoanilide or nitranilide is treated with ammonia or a monoalkyl amine under pressure in the presence of a copper catalyst, the acyl group, if present, is removed, and the nitro group, if present, is reduced; the derivatives of sulphanilic acid used in processes (a), (b) and (c) above may be replaced by the corresponding derivatives of N-alkylsulphanilic acids. In the examples: (1) acetylsulphanilic acid chloride (from acetanilide and chlorsulphonic acid) is condensed with p-phenylenediamine, and the product is boiled with hydrochloric acid; sulphanilic acid 4 - aminoanilide is obtained and, as a by-product, di(p-aminobenzenesulphonyl) - p - phenylenediamine; (2) propionylsulphanilic acid chloride is condensed with p-aminoacetanilide, and the product is boiled with caustic soda solution; sulphanilic acid 4-aminoanilide is again obtained; (3) benzoylsulphanilic acid chloride is condensed with m-nitraniline, and the product is boiled with caustic soda to yield sulphanilic acid 3-nitranilide; the nitro group is then reduced by hydrogenation in the presence of nickel; (4) sulphanilic acid anilide is nitrated in sulphuric acid to yield sulphanilic acid 4-nitranilide; the nitro group is then reduced with zinc dust or by catalytic hydrogenation; (5) acetylsulphanilic acid amide is condensed with p-bromacetanilide to yield acetylsulphanilic acid 4-acetaminoanilide, which is saponified with caustic soda solution to yield sulphanilic acid 4 - aminoanilide; (6) acetylsulphanilic acid amide is condensed with o-chloronitrobenzene to yield acetylsulphanilic acid 2-nitranilide, which is saponified with caustic soda solution to yield sulphanilic acid 2-nitranilide; the nitro group is then reduced by catalytic hydrogenation; (7) p-chlorobenzenesulphonic acid 4-acetaminoanilide is heated with methylamine in the presence of copper bronze, and the product is boiled with caustic soda solution; N-methylsulphanilic acid 4-aminoanilide is obtained; (8) p-chlorobenzenesulphonic acid 4-nitranilide is heated with ammonia solution in the presence of cuprous chloride to yield sulphanilic acid 4-nitranilide; the nitro group is then reduced by catalytic hydrogenation.