Catalytic asymmetric construction of C2-symmetric contiguous quaternary carbon centers enabled a concise synthesis of (−)-chimonanthidine and (−)-folicanthine. (12th January 2023)

• Record Type: Journal Article
• Authors: Xu, Yuanzhen; Lei, Pan; Fei, Yuanai; Hou, Yi; Chen, Guzhou; Zhou, Zhiqiang; Zou, Huanhuan; Wei, Hongbo; Xie, Weiqing
• Is Part Of: Tetrahedron letters. Volume 114(2023)
• Publication Date: 2023-01-12
• Subjects: Asymmetric catalysis -- Cyclotryptamine alkaloids -- Conjugated addition -- (−)-Chimonanthidine -- (−)-Folicanthine; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2022.154261
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: Abstract: Herein, we disclose a catalytic asymmetric conjugated addition of 3-substutited oxindoles to indol-2-one in situ generated from 3-bromooxindoles promoted by Ni(BF4 )2 ·6H2 O/chiral N, N′ -chiral dioxide. This protocol enables forging C2 -symmetric CQCCs in excellent enantioselectivities as single diastereoisomer via directly fusing two congested 3-substituted oxindoles. The asymmetric synthesis of (−)-chimonanthidine and (−)-folicanthine is concisely achieved respectively in four and five steps by taking advantage of this protocol.