Palladium‐Catalyzed [6+2] Double Allene Annulation for Benzazocines Synthesis
Haibo Xu, Shengming Ma
Abstract
An efficient double allene protocol for the formation of benzazocines has been developed. The reaction constitutes a highly regioselective palladium-catalyzed formal [6+2] annulation of allenyl benzoxazinanones with terminal allenes forming the challenging 8-membered cycles. Decent yields and excellent regioselectivity have been observed under mild conditions with a remarkable Z-stereoselectivity for the exo-cyclic C=C bonds. The synthetic potentials of benzazocine products have been demonstrated.
Topics & Concepts
AlleneRegioselectivityAnnulationPalladiumChemistryStereoselectivityCatalysisDouble bondCombinatorial chemistryStereochemistryMedicinal chemistryOrganic chemistryCatalytic C–H Functionalization MethodsCatalytic Alkyne ReactionsCatalytic Cross-Coupling Reactions