文献类型：期刊文献

英文题名：Cooperative N-heterocyclic Carbene and Iridium Catalysis Enables Stereoselective and Regiodivergent [3+2] and [3+3] Annulation Reactions

作者：Zhang, Jian[1,2];Gao, Yan-Shan[1,2];Gu, Bu-Ming[3];Yang, Wu-Lin[1,2];Tian, Bo-Xue[3];Deng, Wei-Ping[1,2]

机构：[1]East China Univ Sci & Technol, Sch Pharm, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Shanghai Key Lab New Drug Design, Shanghai 200237, Peoples R China;[3]Tsinghua Univ, Sch Pharmaceut Sci, Beijing 100084, Peoples R China

年份：2021

卷号：11

期号：7

起止页码：3810

外文期刊名：ACS CATALYSIS

收录：;EI(收录号：20211410179434);WOS:【SCI-EXPANDED(收录号:WOS:000637003700005)】；

基金：This work was supported by the National Natural Science Foundation of China (No. 21901072), the Shanghai Sailing Program (No. 18YF1405600), the Tsinghua-Peking University Center for Life Sciences (No. 61020100120), and the Start-up Foundation of Tsinghua University (No. 53332201420). We greatly appreciate Prof. S. Ye (Institute of Chemistry, Chinese Academy of Sciences, ICCAS) for helpful discussions. The authors also thank the Research Center of Analysis and Test of the East China University of Science and Technology for assistance with the HRMS and NMR analyses.

语种：英文

外文关键词：cooperative catalysis; regiodivergent annulation; iridium; N-heterocyclic carbenes; stereodivergent synthesis

摘要：A cooperative N-heterocyclic carbene (NHC)/iridium catalysis has been developed to achieve highly stereo-selective and regiodivergent [3 + 2] and [3 + 3] annulation reactions of 2-indolyl allyl carbonates with enals. The use of the NHC catalyst has introduced switchable homoenolate and enolate intermediates from the common enal precursor via a simple adjustment of reaction conditions in a predictable manner. This protocol furnishes two types of biologically important products, pyrrolo[1,2-a]indoles and pyridine[1,2-a]indoles, with high diastereo- and enantioselectivities (up to >20:1 dr and >99% ee). Notably, all four stereoisomers of these products with two vicinal stereocenters could be afforded through permutations of the enantiomers of the two chiral catalysts. Mechanistic investigations and further computational density functional theory calculations give an explanation of the origin of the regioselectivity. In addition, the NHC-enolate intermediate generated from formylcyclopropanes was also compatible in this cooperative catalytic system and thus the arsenal of optically pure pyrrolo[1,2-a]indole products was enriched.