Michael Addition of Acyclic Lithium 1,3-Dien-2-olates with α,β-Unsaturated Esters, Ketones, and Diesters

Abstract

Abstract The Michael addition of lithium 1,3-dien-2-olates with α,β-unsaturated carbonyl compounds is described. With α,β-unsaturated esters the reaction was reversible even at −78°C, while kinetically controlled with α,β-unsaturated ketones or alkylidenemalonates. At room temperature, the initially formed Michael adducts undergo subsequent intramolecular Michael addition to give substituted cyclohexanone derivatives in a highly stereoselective manner. Mostly anti-selectivity has been observed for the initial Michael addition, and the intramolecular cyclization was cis-selective.