Enantioselective Excited-State Nazarov Reaction: A Relay Strategy of Electrocyclization and Parallel Kinetic Resolution

We report herein the enantioselective photoinduced Nazarov reaction using a relay strategy of an electrocyclization, followed by parallel kinetic resolution (PKR). No enantioselectivity was observed during electrocyclization due to weak coordination between chiral ligands and the substrate’s carbonyl group. However, PKR was successfully achieved in the deprotonation step with a bifunctional chiral thiourea ligand. Regioselective deprotonation, controlled by the chiral N,N-dimethyl amine motif, produced cis-6,5,6-fused tricyclic stereoisomers with high ee and yields.