Photochemical reactions of α,β-unsaturated γ,δ-epoxy ketones and nitriles in the presence of amine

Abstract

Direct irradiation (λ 254 nm) of the α,β-unsaturated γ,δ-epoxy ketone (1) and nitrile (2) in acetonitrile in the presence of aliphatic amines gave the divinyl ethers (5) and (11), respectively, as the main products, whose formation was shown to depend on solvent polarity and ionization potential of amines. On the other hand, when compounds (1) and (2) were irradiated in various alcohols in the presence of an amine they afforded the corresponding ketals (14)–(19) and (21) in 85–21% yield. Photochemical reactions of ketone (3) and nitrile (4) in methanol, were also studied.