Cu(I)–BINAP-Catalyzed Synthesis of β-Lactams via EnT-Driven 1, 5-HAT

We report a Cu(I)–BINAP-catalyzed, visible-light-induced cyclization of α,β-unsaturated amides to β-lactams. This protocol utilizes triplet energy transfer to trigger a key intramolecular 1,5-HAT for ring closure. By avoiding preactivated substrates, this method offers an efficient, mild route to strained heterocyclic motifs, demonstrating the synthetic utility of copper photocatalysis.