GB551206A - Improvements in and relating to the manufacture of sulphonamido compounds - Google Patents

Abstract

551,206. Aryl sulphenamides and sulphonamides. MANCHESTER OXIDE CO., Ltd., BANN, B., KRUG, P., WHEELER, D. E., TAYLOR, W., and GLADDING, G. April 29, 1941, Nos. 7284/42, 7285/42, [both divided out of 553,269], and 7077/42. [Class 2 (iii)] Benzenesulphonamidopyridines and p-substituted derivatives thereof are prepared by the oxidation of the corresponding sulphenamides, e.g. with alkali or alkaline earth metal permanganate or hypochlorite. The sulphenamides may be obtained by treating a diphenyldisulphide with chlorine in a non-aqueous medium and reacting the resulting sulphenyl chloride with an aminopyridine ; the diphenyldisulphides may be prepared by heating with caustic alkali a thiocyanobenzene obtainable as described in Specifications 513,473 and 514,203. The sulphenamides may also be prepared by reacting a benzenesulphenyl ester or a benzenesulphenamide with an aminopyridine. The substituent in the p-position is preferably a halogen atom or a nitrogencontaining group convertible into an amino group, e.g. an acylamino or nitro group, and the products may be converted into the amino compounds which are useful therapeutically. According to the examples, (1) 2-benzenesulphonamidopyridine is prepared by chlorinating diphenyldisulphide in chloroform, treating the resulting benzenesulphenyl chloride with 2-aminopyridine in dry benzene and oxidizing the 2-benzenesulphenamidopyridine so formed with aqueous potassium permanganate ; (2) 2-(4<SP>1</SP>-aminobenzenesulphonamido)-pyridine is obtained by reacting p-nitrobenzenesulphenyl chloride with 2-aminopyridine, oxidizing the resulting2-(4<SP>1</SP>-nitrobenzenesulphenamido)-pyridine with potassium permanganate solution and reducing the product with iron and acetic acid ; the sulphenyl chloride may be converted into the sulphenic acid ester by interaction with sodium ethoxide and this treated with 2- aminopyridine and oxidized to the 2-(41-nitrobenzenesulphonamido)-pyridine ; (3) 2.- (41- nitrobenzenesulphenamido)-pyridine is oxidized to the sulphonamido compound with aqueous calcium permanganate or sodium hypochlorite; the same product is obtained by heating p-nitrobenzenesulphenamide with 2-aminopyridine in benzene and oxidizing as before ; (4) 2-(4<SP>1</SP>-aminobenzenesulphonamido)-pyridine results when 4:4<SP>1</SP>-diacetyldiaminodiphenyldisulphide is treated in chloroform with chlorine, the p-acetylaminobenzenesulphenyl chloride so formed reacted with 2-aminopyridine, and the product, after oxidation with permanganate, hydrolysed with caustic soda ; (5) 2-(41-chlorobenzenesulphonamido)-pyridine is prepared by first chlorinating 4 : 4<SP>1</SP>-dichlorodiphenyldisulphide in chloroform, then reacting the p-chlorobenzenesulphenyl chloride with 2- aminopyridine, and finally oxidizing the sulphenamido product with potassium permanganate ; the product may be converted into the 41-amino compound by treatment with ammonia ; (6) p-chlorobenzenesulphenamide, prepared by treating p-chlorobenzenesulphenyl chloride with ammonia, is heated in benzene with 2-aminopyridine and the resulting 2-(4<SP>1</SP>- chlorobenzenesulphenamido)-pyridine then oxidized as in (5). Specification 379,683 also is referred to. The first Provisional Specification refers to the production of the naphthyl compounds.