Patent GB-751889-A (GB)
Title: Preparation of salts of s-aryl-thiosulfuric acids
IPC: C07C381/02
Filed: 1954-04-12
Abstract: A process for preparing salts of S-aryl-thiosulphuric acids consists in treating compounds of the formula Ar-S-X, where Ar stands for an aryl group and X is an amido group linked to the sulphur by nitrogen, with aqueous sulphurous acid.  The invention also comprises compounds of the general formula <FORM:0751889/IV(a)/1> where Me stands for a cation, e.g. an ammonium ion derived from an amine, or potassium, of value in the treatment of coccidiosis of chickens.  Where the amide starting material is soluble in water, water may be employed as reaction medium otherwise a mixture of a water-miscible organic solvent such as alcohol, acetone or dioxane with water may be employed.  The amide starting material may be represented by the general formula <FORM:0751889/IV(a)/2> wherein R and R1 may be hydrogen, alkyl, cycloalkyl or aryl groups and may together be part of a heterocyclic ring, e.g. in a piperidide, morpholide and piperazide, the aryl group may be an unsubstituted aryl group such as phenyl or naphthyl or a homologue such as alkyl phenyl or alkyl naphthyl or it may have other substituent groups such as alkoxy, halogen, nitro, carbonyl or nitrile.  The amine salt of the S-aryl-thiosulphuric acid is produced initially and this can be transformed into any other suitable salt by metarthesis.  Other cations mentioned are those of alkali metals, metals of the record group of the Periodic System, and polyvalent metals such as aluminium, iron and zinc. S-aryl-thiosulphuric acids may be hydrolysed to obtain sulphuric acid and the corresponding thiol with mineral acids or an unstable sulphuric acid disproportionating into a disulphide and sulphinic acid.  In examples: the dimethylamine salt of S-2-nitrophenyl thiosulphuric acid is obtained in solution by passing sulphur dioxide into an aqueous suspension of 2-nitrobenzene sulphenyl dimethylamide; the potassium salt is precipitated by the addition of potassium chloride to the aqueous solution or potassium hydroxide to a methanol solution (1); the cyclohexylamine salt of S-2,4-dinitrophenylthiosulphuric acid is obtained by treating 2,4-dinitrobenzene-sulphenyl cyclohexylamide dissolved in alcohol with aqueous sulphur dioxide; the potassium salt is obtained by treating a methanol solution of the cyclohexylamine salt with potassium hydroxide (2); S-2,4-dinitrophenylthiosulphuric acid is obtained by reacting the sulphenyl piperidide obtained by reaction of 2,4-dinitrobenzene-sulphenyl chloride with piperidine in an inert organic solvent, in alcohol with aqueous sulphur dioxide (3); the aniline salt of S-phenylthiosulphuric acid is obtained by reacting the anilide of benzenesulphenic acid with aqueous sulphur dioxide (4); the ammonium salt of S-1-anthraquinonylthiosulphuric acid is obtained by treating a slurry of a -anthraquinonesulphenyl amide in a mixture of alcohol and water with sulphur dioxide and adding ether; the potassium salt is obtained by adding potassium hydroxide to a methanolic solution of the ammonium salt (5); the diethylamine salt of S-3-nitrophenylthiosulphuric acid is obtained by treating with sulphur dioxide, in an aqueous ethanol slurry, the crude anide obtained by reacting 3,31-dinitrodiphenyl disulphide with chlorine in carbon tetrachloride and adding diethylamine to the product; S-3-nitrophenylthiosulphuric acid forms water-soluble sodium, potassium, calcium, barium, zinc, copper and ferric salts, the potassium salt by adding potassium hydroxide to the methanol solution of the diethylamine salt (6); the dicyclohexylamine salt of S-3-nitrophenylthiosulphuric acid is obtained by treating with sulphur dioxide an aqueous ethanol slurry of the amide obtained by treating 3,31-dinitrodiphenyl-disulphide with chlorine in carbon tetrachloride and adding dicyclohexylamine to the product (7).