Perfluoroalkyl derivatives of sulphur. Part XV. Preparation and certain reactions of methyl polyfluoroalkyl sulphoxides and sulphones and their conversion into polyfluoroalkanesulphonic acids

Abstract

Oxidation of various methyl polyfluoroalkyl sulphides and of ethyl trifluoromethyl sulphide gives either the corresponding sulphoxides or the sulphones depending on the oxidising agent or the conditions used. Carbanion formation with both the sulphoxides and the sulphones has been demonstrated by deuterium exchange and by reaction with sodium hypochlorite, and with methyl heptafluoro-n-propyl sulphone by reaction with benzaldehyde and with iodine in the presence of base to give heptafluoro-n-propyl trans-styryl sulphone and tri-iodomethyl heptafluoro-n-propyl sulphone, respectively, in high yield. Oxidation of methyl heptafluoro-n-propyl sulphone with neutral permanganate or basic hydrolysis of trichloromethyl heptafluoro-n-propyl sulphone gives heptafluoro-n-propane-1-sulphonic acid as its potassium salt in good yield.