Institute for Advanced Study, Chengdu University, Chengdu 610106, China.
School of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang, 550025, China.
J Org Chem. 2021 Feb 5;86(3):2534-2544. doi: 10.1021/acs.joc.0c02653. Epub 2021 Jan 10.
A highly diastereo- and enantioselective cyclopropanation reaction of 3-acylcoumarins with 3-halooxindoles catalyzed by an organocatalyst through a [2 + 1] Michael/intramolecular cyclization process was developed. This scenario provides a facile strategy to access spirooxindole-cyclopropa[]coumarin compounds bearing three continuous stereocenters, including two vicinal quaternary all-carbon stereocenters with high to excellent diastereo- and enantioselectivities. The HRMS study revealed the vital importance of the ammonium ylide intermediate in the catalytic process.
一种通过[2 + 1]迈克尔/分子内环化过程由有机催化剂催化的 3-酰基香豆素与 3-卤代氧杂吲哚的高非对映选择性和对映选择性环丙烷化反应被开发出来。这种情况为获得具有三个连续立体中心的螺氧吲哚-环丙烷香豆素化合物提供了一种简便的策略，包括两个相邻的季碳全碳立体中心，具有高至优异的非对映选择性和对映选择性。高分辨质谱研究揭示了铵叶立德中间体在催化过程中的重要性。
