COOXIDATION REACTION IN THE SINGLET OXYGENATION OF CYCLIC AND BENZYLIC SULFIDES - S-HYDROPEROXYSULFONIUM YLIDE INTERMEDIATE AS A NEW EPOXIDIZING SPECIES
The reaction of singlet oxygen with a series of 3-benzoyl-4-(methoxycarbonyl)thiazolidine derivatives and alkyl benzyl sulfides in methylene chloride in the presence of olefins has been investigated. The reaction of singlet oxygen with the sulfides caused cooxidation of olefins to the corresponding epoxides in substantial yields. The epoxidation of olefins by the active oxidizing species generated in photosensitized oxygenation of the sulfides is provided, suggesting that the new epoxidizing species is probably the S-hydroperoxysulfonium ylide intermediate derived from a persulfoxide intermediate by intramolecular alpha-proton abstraction.