Asymmetric Synthesis of α-Alkylidene-β-Lactams through Copper Catalysis with a Prolinol-Phosphine Chiral Ligand.

A copper/prolinol-phosphine chiral catalyst enabled the one-step synthesis of chiral α-alkylidene-β-lactams. Optimization of the chiral ligand for steric and electronic properties realized the highly enantioselective coupling of nitrones and propargyl alcohol derived alkynes. The resulting chiral α-alkylidene-β-lactams served as a platform for various β-lactams via well-established transformations of α,β-unsaturated carbonyl compounds.