Facile synthesis of γ-alkenylbutenolides from Baylis–Hillman adducts: consecutive in-mediated Barbier allylation, PCC oxidation, isomerization, and Zn-mediated Barbier allylation

Alkenylbutenolides were synthesized regioselectively in good to moderate yields from Baylis–Hillman adducts via a consecutive indium-mediated Barbier type reaction between Baylis–Hillman bromide and aldehyde, PCC oxidation of the homoallylic alcohol, double bond isomerization, and zinc-mediated Barbier type alkenylation protocol.