Photolysis of some β,γ-epoxycarbonyl compounds

Abstract

Photolysis of (3RS)-3,4-epoxy-1-phenylbutan-1-one (1a) gives in high yield a 1.7 : 1 mixture of (1RS,2RS,3RS)- and (1RS,2SR,3SR)-2,3-epoxy-1-phenylcyclobutan-1-ols (4) and (5). Fragmentation of the intermediate biradical is not a competitive reaction process. Alkyl substitution at C 2 facilitates α-cleavage while the 2-oxa analogue, oxiranyl benzoate (2), is unreactive under normal photolysis conditions.