Construction of polycyclic spirooxindoles through [3+2] annulations of Morita-Baylis-Hillman carbonates and 3-nitro-7-azaindoles

An array of polycyclic spirooxindoles containing fused azaindoline frameworks and vicinal quaternary centers have been constructed in excellent yields and diastereoselectivity through a DMAP-catalysed dearomatic [3+2] annulation reaction.