Oxygenation with Molecular Oxygen. Thermal and Photochemical Epoxidation of Propylene in the Presence of Sulfur Dioxide in Acetonitrile at Ambient Temperature

Article abstract of DOI:10.1021/ja00403a044

Irradiation of a mixture of propylene and sulfur dioxide in acetonitrile at ice-cold temperature causes absorption of molecular oxygen and gives propylene oxide as the sole volatile product.Also, in the absence of light, the addition of nitrile or nitrate salts to a mixture of sulfur dioxide and propylene in acetonitrile under oxygen at room temperature leads to the smooth formation of propylene oxide as the only volatile product.Both reactions show quite similar solvent dependence and are retarded by the additives with ionization potentials lower than ca. 9.5 eV.The main byproduct is poly(propylenesulfonate).The mechanisms of the epoxidation reactions are discussed.