Conversion of α,β-Unsaturated Esters to Their β,γ-Unsaturated Isomers by Photochemical Deconjugation

Article abstract of DOI:10.1021/jo00206a030

It is shown that the α,β-unsaturated esters 1, 2, 4, 5, 6, 16, and 18, which have been reported to be inert to photochemical deconjugation or to undergo the reaction inefficiently, can be converted to their β,γ-unsaturated isomers in good yield if the irradiation is performed in the presence of a catalytic amount of a weak base such as 1,2-dimethylimidazole.It is also shown that addition of catalytic amounts of base can alter the product distribution in cases such as 11, 23, and 26 where more than one isomer can be formed.