Photochemical rearrangement of diene endoperoxides

Abstract

It has been shown that the direct irradiation of cyclic peroxides such as ascaridole, and those derived from cyclohexadiene, 1,3,5,5-tetramethylcyclohexadiene, and levopimaric acid methyl ester rearrange on irradiation. The bisepoxides are obtained, as in the thermal rearrangement, together with, where the structure permits, the ketoepoxide. The reaction can be induced by triplet–triplet energy transfer.