Photochemical Reactions of Contact Charge-Transfer Pairs of 1-Arylcyclohexenes and Oxygen

Article abstract of DOI:10.1246/bcsj.60.3331

Photoexcitation of contact charge-transfer (CCT) pairs of 1-arylcyclohexenes 1 (aryl: phenyl, 4-methylphenyl, and 4-methoxyphenyl) and oxygen in acetonitrile and benzene gave 1,2-epoxy-1-arylcyclohexanes 2 as major products together with 2-aryl-2-cyclohexen-1-ols and acetophenones 4.Similar irradiation of the CCT pairs in methanol/acetonitrile afforded mainly 2-aryl 2-cyclohexen-1-ones, and 4.The formation of these products can be explained by photoinduced electron transfer in the excited CCT pairs generating radical cations of 1 and superoxide anions.