Patent ID: 7129358

Claim:
A process for preparing a thioester compound of formula A: wherein R 1 , R 2 , and R 4 are each selected from the group consisting of hydrogen, substituted or unsubstituted lower alkyl and substituted or unsubstituted lower alkoxy; and R 3 is selected from the group consisting of hydrogen and substituted or unsubstituted lower alkyl, comprising reacting a thioether compound of formula B: wherein R 1 through R 4 are as in formula A, with tert-butyl hydroperoxide in the presence of a catalyst to produce selective oxidation of the thioether compound of formula B to form the thioester compound of formula A, wherein the molar ratio of tert-butyl hydroperoxide to the compound of formula B is in the range of about 1.24:1 to about 4.5:1.