Lewis Base and Brønsted Base Dual-Catalyzed Formal [4+3] Cycloaddition Reaction: Synthesis of Aza-Spirocycloheptane Oxindole

Jin-Yu Liu, Hong Lu, Chen-Guang Li, Yong-Min Liang and Peng-Fei Xu*

http://dx.doi.org/10.1055/s-0035-1560600.