Oligomeric iodosylbenzene sulfate: A convenient hypervalent iodine reagent for oxidation of organic sulfides and alkenes

Oligomeric iodosylbenzene sulfate, (PhIO)₃·SO ₃, which can be formally considered as a partially depolymerized activated iodosylbenzene, is a readily available, stable, and water-soluble hypervalent iodine reagent that is useful for the oxidation of sulfides or alkenes. Furthermore, this reagent can be conveniently generated in situ from (diacetoxyiodo)benzene and sodium bisulfate and used without isolation in oxidations in aqueous solution or under solvent-free conditions. The reaction of iodosylbenzene sulfate in situ with organic sulfides at room temperature affords sulfoxides in high yields without over-oxidation to sulfones, and this reaction is compatible with the presence in the substrate molecule of hydroxy groups, double bonds, benzylic carbon atoms, carboxylate groups, and various substituted phenyl rings. The reaction of an alkene with iodosylbenzene sulfate generated in situ results in oxidative rearrangement to form a ketone or aldehyde.