Stereoselective Synthesis of Tri- and Tetrasubstituted α,β-Unsaturated Esters via Copper-catalyzed Coupling of Enol Triflates of β-Ketoesters with Grignard-based Zinc Ate Complexes

Tri- and tetrasubstituted α,β-unsaturated esters were stereoselectively prepared via the copper-catalyzed couplings of the enol triflates of β-ketoesters with Grignard-based zinc ate complexes. Some insights into the mechanistic considerations are described.