PHOTOCHEMISTRY OF 5,6-EPOXY-1,3-DIENES. INFLUENCE OF A 7-HYDROXY SUBSTITUENT

Article abstract of DOI:10.1016/S0040-4020(01)92382-8

Triplet sensitization of the 7-hydroxy-5,6-epoxy-1,3-diene 10 causes cleavage of the C(5),O epoxide bond followed by the formation of the three isomers 11-13 or induces scission of the C(6),C(7) bond followed by the formation of the aldehyde 14 and the bicyclo<3.2.0> heptanols 15 and 16.However, irradiation of the corresponding acetate 18 gives only C(5),O epoxide bond scission (18<*>f) followed by the cyclization process f<*>19, the 1,2-Me shifts f<*>20,21 and the γ-H abstraction f<*>g leading to the cyclopropane formation g<*>22.