Asymmetric Michael addition of malonates to unsaturated ketones catalyzed by rare earth metal complexes bearing phenoxy functionalized chiral diphenylprolinolate ligands

A simple, efficient catalytic asymmetric Michael addition of malonates to unsaturated ketones has been successfully developed. This process was promoted by rare earth metal complexes 1-4, which is bearing chiral phenoxy functionalized prolinol ligand at room temperature. The Sc complex 3 performed the best and the products reached up to 99% yield and 90% ee.