Organo-Cation Catalyzed Asymmetric Homo/Heterodialkylation of Bisoxindoles: Construction of Vicinal All-Carbon Quaternary Stereocenters and Total Synthesis of (−)-Chimonanthidine

• DOI: 10.1021/jacs.8b05386
• Publication Date: 2018-08-01T20:54:31Z
• Authors: Si-Kai Chen; Wen-Qiang Ma; Zhi-Bo Yan; Fu-Min Zhang; Shao-Hua Wang; Yong-Qiang Tu; Xiao-Ming Zhang; Jin-Miao Tian
• Keywords: 01 natural sciences; 0104 chemical sciences

A novel chiral spirocyclic amide (SPA)-derived triazolium organocatalyst has been designed and demonstrated to effect asymmetric homo- and heterodialkylations of various bisoxindoles, enabling enantioselective construction of vicinal all-carbon quaternary stereocenters. These reactions feature excellent enantio- and diastereoselectivities (up to 99% ee and >20:1 dr) as well as good to high yields (up to 89% over two steps). As an application of this methodology, the first asymmetric total synthesis of (-)-chimonanthidine has been achieved.