Organocatalytic asymmetric oxy-Michael addition to a γ-hydroxy-α,β-unsaturated thioester via hemiacetal intermediates.

Abstract

We report an asymmetric oxy-Michael addition to a γ-hydroxy-α, β-unsaturated thioester via hemiacetal intermediates in the presence of Cinchona-alkaloid-thiourea-based bifunctional organocatalysts. This method provides a novel enantioselective route to β-hydroxy carboxyl compounds, which in turn can be used to synthesize valuable chiral building blocks.