Phosphine/Palladium Cooperative Catalysis: (4 + 3) Annulations of Morita-Baylis-Hillman Carbonates and Vinyl Benzoxazinanones.

A novel (4 + 3) annulation reaction of Morita-Baylis-Hillman carbonates and vinyl benzoxazinanones has been developed by using phosphine/palladium dual catalysis. This reaction demonstrates a wide substrate scope, providing a range of vinyl 2, 3-dihydro-1H-benzo[b]azepine derivatives in moderate to good yields and diastereoselectivities. Experimental results indicate that both palladium and phosphine play crucial roles in the annulation reactions.