Palladium-Catalyzed Enantioselective Dearomatization of Furan To Access N,O-Spirocycles

N,O-Spirocycles are important structural motifs in efficient chiral ligands, natural products, and pharmaceuticals. However, the achievement of highly enantioselective N,O-spirocycles remains a challenge. Herein, we present a Pd-catalyzed enantioselective dearomatization of bromofurans with N-tosylhydrazones using a newly developed chiral sulfinamide phosphine ligand. The reaction features an excellent Z/E ratio, high enantioselectivity, and mild reaction conditions. The synthetic versatility of N,O-spirocycles is demonstrated.