Organocatalytic Asymmetric Synthesis of Aza-Spirooxindoles via Michael/Friedel–Crafts Cascade Reaction of 1,3-Nitroenynes and 3-Pyrrolyloxindoles

• DOI: 10.1021/acs.orglett.1c00409
• Publication Date: 2021-03-03T18:45:28Z
• Authors: Qijian Ni; Xuyang Wang; Da Zeng; Qianling Wu; Xiaoxiao Song
• Keywords: 01 natural sciences; 0104 chemical sciences

An asymmetric [3+3] cyclization of nitroenynes and 3-pyrrolyloxindoles has been realized with a chiral bifunctional squaramide catalyst. This Michael/Friedel-Crafts cascade strategy provides a facile and efficient access to enantioenriched polycyclic aza-spirooxindoles with 32-95% isolated yields and excellent stereocontrol under mild reaction conditions.