Enantioselective Epoxidation of Unfunctionalized Olefins with Molecular Oxygen and Aldehyde Catalyzed by Optically Active Manganese(III) Complexes

Enantioselective epoxidation of unfunctionalized olefins with combined use of molecular oxygen, an oxidant, and pivalaldehyde, a reductant, was demonstrated in the presence of a catalytic amount of optically active Mn(III)-salen complexes. Dihydronaphthalene derivatives were converted into the corresponding optically active epoxides in good yields with 60–77% enantiomeric excesses.