Patent ID: 8232429

Claim:
A method for producing an oxidized cyclic phenol sulfide which comprises the step of oxidizing a cyclic phenol sulfide of the following formula (1) as a raw material: wherein R represents a straight or branched alkyl group having 1 to 6 carbon atoms, and m is an integer from 4 to 8, in an organic carboxylic acid solvent not comprising a halogen atom in an amount of 2 or more and less than 10 parts by weight per 1 part by weight of the cyclic phenol sulfide, with hydrogen peroxide as an oxidizing agent(s) to obtain an oxidized cyclic phenol sulfide of the following formula (2): wherein R represents a straight or branched alkyl group having 1 to 6 carbon atoms, m is an integer from 4 to 8, and n is 1 or 2 wherein no halogenated hydrocarbon is used as a solvent in the oxidation reaction; in the presence of a metal catalyst; wherein the metal catalyst is a tungsten acid or sodium tungstate; and wherein a metal salt of an organic carboxylic acid is used in mole ratios of 0.01 to 5 per 1 mole of the tungsten acid or sodium tungstate; and wherein the metal salt of an organic carboxylic acid is sodium acetate.