Phosphine-Catalyzed[4+1] Annulation of Salicyl Imines with Maleimides and Synthesis of Spiro[benzofuran-2,3'-pyrrolidine] Derivatives
Yang Mei, Cao Shixuan, He Zhengjie
Chin. J. Org. Chem. . 2019, (8): 2235 -2242 .  DOI: 10.6023/cjoc201904041