Patent GB-546277-A (GB)
Title: Improvements in the manufacture of aromatic compounds containing sulphur
Filed: 1940-09-27
Abstract: 546,277. Aromatic aminosulphones. MANCHESTER OXIDE CO., Ltd., CLAYTON, J. H., and BANN, B. Sept. 27,1940, No. 14614. [Class 2 (iii)] p- Aminophenyl sulphones of the general formula (other than those having an alkoxy group in o-position to the amino group NH 2 ), wherein R represents an alkyl, aralkyl or aryl group and the benzene ring may carry substituents or condensed nuclei, are obtained from p-thiocyanoaniline or the corresponding derivatives thereof (obtainable as described in Specifications 513,473 and 514,203) by the steps of (a) acylating the amino group, (b) replacing the thiocyano group by the mercapto group, (c) etherifying the mercapto group by treatment with an etherifying agent, (d) oxidizing to produce the corresponding sulphone, and (e) hydrolysing the acylamino group. Specified acyl groups are acetyl and benzoyl and specified substituents R are alkyl groups containing up to 16 carbon atoms,-CH 2 .COOH, benzoyl, 2- or 4-nitrophenyl and 2:4-dinitrophenyl. Specified nuclear substituents are halogen, alkyl, aralkyl, alkoxy and aryloxy. The preferred oxidizing agent is an alkali metal permanganate in aqueous solution, suitably containing acetic acid. Examples relate to the production of (1) 3-methyl-4-aminophenyl ethyl sulphone from 5-thiocyano-2-aminotoluene by the steps of (a) acetylating with acetic anhydride in glacial acetic acid, (b) replacing the thiocyano group by the mercapto group by treatment with sodium sulphide in alcohol, (c) etherification of the mercapto group by treatment with diethyl sulphate in alcohol, (d) oxidizing the resulting thioether by treatment with potassium permanganate in aqueous acetic acid and (e) hydrolysing the acetylamino group with hydrochloric acid in alcohol; there may be similarly obtained 4-aminophenyl methyl or ethyl sulphone, 2- or 3-methyl-4- aminophenyl methyl sulphone, 2-methyl-4- aminophenyl ethyl sulphone and 3-chloro-or 3:6-dichloro-4-aminophenyl ethyl sulphone; (2) 3-chloro-4-aminophenyl n-butyl sulphone from 3-chloro-4-amino-thiocyanobenzene, by steps corresponding to those in (1), the oxidation being effected under milder conditions to avoid oxidation of the butyl group ; there may be similarly obtained 4-aminophenyl n-butyl sulphone and its 3-methyl-6-chloro derivative; (3) 4-aminophenyl n-hexyl sulphone from 4- thiocyanoaniline by steps corresponding to those in (2), the etherification of the mercapto group being effected by treatment with n-hexyl iodide in alcohol; there may be similarly obtained 4-aminophenyl hexadecyl sulphone and 3-methyl- or 3:6-dimethyl-4-aminophenyl dodecyl sulphone ; (4) 4-amino-2<SP>1</SP>-nitrodiphenyl sulphone from 4-thiocyanoaniline by steps corresponding to those in (1) with the use, as etherifying agent, of o-chloronitrobenzene in alcohol; there may be similarly obtained 4- aminophenyl benzyl sulphone, 4-amino-4<SP>1</SP>-nitrodiphenyl.sulphone and its 3-methyl derivative and 4-amino-2<SP>1</SP>:4<SP>1</SP>-dinitrodiphenyl sulphone ; (5) 3-(41-methoxyphenoxy)-4-aminophenyl nbutyl sulphone from 4-thiocyano-2-(4<SP>1</SP>-methoxyphenoxy)-aniline by steps corresponding to those in (2) with the use, as etherifying agent, of n-butyl chloride ; there may be similarly obtained the corresponding methyl, ethyl and n-hexyl sulphones, the 3-(4<SP>1</SP>-ethoxyphenoxy)-4- aminophenyl n-butyl, methyl or ethyl sulphones and the 3-phenoxy-4-aminophenyl ethyl or nbutyl sulphones. Specifications 546,278 and 546,279 also are referred to.