Asymmetric Michael addition reaction of 3-substituted-N-Boc oxindoles to activated terminal alkenes catalyzed by a bifunctional tertiary-amine thiourea catalyst
作者:Xin Li、Zhi-Guo Xi、Sanzhong Luo、Jin-Pei Cheng
DOI:10.1039/b918644a
日期:——
article reports an organocatalytic strategy for the asymmetric catalysis of chiral oxindoles bearing 3-position all-carbonquaternarystereocenters. Accordingly, highly enantioselectiveMichaeladdition reactions of 3-substituted oxindoles to terminal alkenes have been developed by utilizing a bifunctional tertiary-amine thiourea catalyst. The reactions accommodate a number of Michael donor compounds
Chiral Phosphine Catalyzed Asymmetric Michael Addition of Oxindoles
作者:Fangrui Zhong、Xiaowei Dou、Xiaoyu Han、Weijun Yao、Qiang Zhu、Yuezhong Meng、Yixin Lu
DOI:10.1002/anie.201208285
日期:2013.1.14
Bifunctional phosphines derived from amino acids mediate the asymmetric Michaeladdition of 3‐substituted oxindoles to activated alkenes (see scheme). Biologically relevant chiral 3,3‐disubstitutedoxindoles were thus prepared in high yields and with excellent enantioselectivities from 3‐aryl‐ and 3‐alkyl‐substituted oxindoles and various activated alkenes.
approach for the design of chiral quaternary phosphonium bromides as chiral phase-transfer catalysts was demonstrated. A catalyst library of phosphonium salts with various structures was readily constructed using commercially available chiral phosphines as catalyst precursors, and an optimized catalyst was successfully applied to highlyenantioselectiveconjugateadditions under base-free phase-transfer