Base-Catalyzed SO2-Induced Allylic Oxidation of Cyclohexene with Molecular Oxygen

Article abstract of DOI:10.1021/jo01310a004

Sulfur dioxide has been found to promote a novel liquid-phase oxidation of cyclohexene with molecular oxygen in acetic acid as solvent.Oxidation at the allylic position occurs only if the reaction is base-catalyzed; with added acetoxy ions, e.g., the major product obtained is 2-cyclohexen-1-one together with minor amounts of 1,2-cyclohexanediol diacetate (mainly as the trans isomer), while a competitive autoxidation of sulfur dioxide to sulfur trioxide is observed.The results are discussed on the basis of an anion-radical mechanism involving the formation of sulfur dioxide stabilized peroxide ions.