Stereoselective domino conjugate addition of Grignard reagents to lactones followed by reaction with activated alkenes catalyzed by ferrocenyl carbene ligands

Abstract

Ferrocenyl phosphane–carbene ligands catalyze domino reactions composed of conjugate addition of Grignard reagents to α,β-unsaturated lactone followed by enolate trapping with activated alkenes. The corresponding α,β-disubstituted lactones were obtained in medium yields, but with high diastereomeric and enantiomeric purities up to 98:2 er.