GB509804A - Process for the manufacture of sulphinic acid derivatives - Google Patents

Abstract

509,804. Sulphinic acid amides SCHERING AKT.-GES. March 15, 1938, No. 8039. Convention date, March 27, 1937. Samples furnished. [Class 2 (iii)] Sulphinic acid amides of therapeutic value are obtained by the reaction of aromatic sulphinic acid halides, substituted by at least one nitro or acylamino group or halogen atom, with ammonia or a primary or secondary amine. The sulphinic acid halides used as starting materials may be obtained by the action of thionyl chloride on the sulphinic acids, which are themselves obtainable by reducing the corresponding sulphonic acid halides, e.g., with stannous chloride in alcoholic solution or with an alkaline solution of sodium sulphite. In the examples, (1) p-nitrobenzenesulphochloride is treated in alcoholic solution with stannous chloride to yield p-nitrobenzenesulphinic acid, which is converted into its chloride by reaction with thionyl chloride ; the chloride is then treated with ammonia in ethereal solution to yield p-nitrobenzenesulphinamide ; (2) o-nitrobenzenesulphinic acid chloride is produced from the acid and thionyl chloride, and is treated with ammonia in ethereal solution. Reference is made also to (a) the production in similar manner of pacetylaminobenzenesulphinic acid amides, from which p-aminobenzenesulphinic acid amides are obtainable by saponification, suitably in the presence of a reducing agent, (b) the reaction of o- or p-nitrobenzenesulphinic acid chloride with sulphanilic acid amide, and (c) the reaction of the sulphinic acid halides with aminopyridines and aminoquinolines. Samples have been furnished, under Sect. 2 (5), of products prepared from p-nitrobenzenesulphinic acid chloride and (1) dimethylamine and (2) 2-aminopyridine. The Specification as open to inspection under Sect. 91 states that the sulphinic acid halides may contain as substituents hydroxy groups, groups convertible by hydrolysis into hydroxy groups, mercapto groups, carboxylic and sulphonic acid groups, amino groups and arsenic acid groups. It refers also to the reaction of the sulphinic acid halides with alkylamines, anilines and glucosamines. This subject-matter does not appear in the Specification as accepted.