Intramolecular hydrogen transfer during oxidation of beta-hydroxysulfides and alpha-(methyl)thioacetamide. Pulse radiolysis and flash photolysis studies

Hydroxysulfuranyl radicals formed during the (OH)-O-.-induced oxidation of P-hydroxy-sulfides and alpha-(methyl)thioacetamide immediately fragmented t o yield alkylthiomethyl radicals and, as stable products, formaldehyde or c arbon dioxide, respectively. No intermediary sulfur radical cations and the ir dimeric three-electron bonded complexes (S therefore S)(+) were observed at neutral to alkaline pH in contrast to when the sulfur radical cations w ere generated at low pH or through the 4-carboxybenzophenone-sensitized pho tooxidation. A detailed mechanism, including a hydrogen transfer between th e hydroxy/amide group and the oxygen of the hydroxysulfuranyl moiety, withi n a six-membered cyclic structure, is proposed and discussed.