A new methodology for the synthesis of δ-substituted α,β-unsaturated δ-lactones

Abstract

A new protocol for the synthesis of δ-substituted-α,β-unsaturated δ-lactones was developed. Selective reaction of 1,3-dilithiopropyne with ketones, followed by addition of ethyl chloroformate formed ethyl 5-[(ethoxycarbonyl)oxy]-5-substituted-2-ynoates, used as the basic framework for the synthesis of δ-substituted α,β-unsaturated-δ-lactones