银促进异氰基乙酸酯与烷基吡啶盐的（4 + 1）环化反应：1,2-二取代中氮茚的发散性区域选择性合成

Silver-Promoted (4 + 1) Annulation of Isocyanoacetates with Alkylpyridinium Salts: Divergent Regioselective Synthesis of 1,2-Disubstituted Indolizines.

作者信息

Chen Yan, Shatskiy Andrey, Liu Jian-Quan, Kärkäs Markus D, Wang Xiang-Shan

机构信息

School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China.

Department of Chemistry, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.

出版信息

Org Lett. 2021 Oct 1;23(19):7555-7560. doi: 10.1021/acs.orglett.1c02754. Epub 2021 Sep 15.

DOI:10.1021/acs.orglett.1c02754

PMID:34524832

Abstract

An unprecedented silver-promoted regioselective (4 + 1) annulation of isocyanoacetates with pyridinium salts is reported. The established protocol provides controlled, facile, and modular access to a range of synthetically useful N-fused heterocyclic scaffolds containing indolizines, pyrrolo[1,2-]quinolines, pyrrolo[2,1-]isoquinolines, and 1-imidazo[4,5-]indolizin-2(3)-ones. A mechanistic pathway involving nucleophilic addition/protonation/elimination/cycloisomerization is proposed.

摘要

报道了一种前所未有的银促进异氰基乙酸酯与吡啶盐的区域选择性（4 + 1）环化反应。该既定方案提供了一种可控、简便且模块化的方法，可用于合成一系列具有合成价值的含中氮茚、吡咯并[1,2 - ]喹啉、吡咯并[2,1 - ]异喹啉和1 - 咪唑并[4,5 - ]中氮茚 - 2(3) - 酮的N - 稠合杂环骨架。提出了一种涉及亲核加成/质子化/消除/环异构化的机理途径。