文献类型：期刊文献

英文题名：Silver-Catalyzed Amidiniumation of Alkynes: Isolation of a Silver Intermediate, Synthesis of Enamine Amido Carbene Precursors, and an Unprecedented Umpolung of Propiolamide

作者：Lv, Shichang[1,2];Wang, Jiwei[1,2];Zhang, Caiyun[1,2];Xu, Sheng[1,2];Shi, Min[1,2,3];Zhang, Jun[1,2]

机构：[1]E China Univ Sci & Technol, Sch Chem & Mol Engn, Key Lab Adv Mat, Shanghai 200237, Peoples R China;[2]E China Univ Sci & Technol, Sch Chem & Mol Engn, Inst Fine Chem, Shanghai 200237, Peoples R China;[3]Chinese Acad Sci, Shanghai Inst Organ Chem, State Key Lab Organometall Chem, Shanghai 200032, Peoples R China

年份：2015

卷号：54

期号：49

起止页码：14941

外文期刊名：ANGEWANDTE CHEMIE-INTERNATIONAL EDITION

收录：;EI(收录号：20160101757733);WOS:【SCI-EXPANDED(收录号:WOS:000367723400065)】；

基金：Financial support from the Shanghai Pujiang Talent Program (11PJ1402500) and the National Natural Science Foundation of China for financial support (21171056) is greatly acknowledged.

语种：英文

外文关键词：alkynes; carbenes; cyclizations; reaction mechanisms; silver

摘要：A silver-catalyzed amidiniumation of N-propiolic formamidines for the synthesis of novel enamine amido carbene precursors is reported. Isolation of a first silver intermediate in silver-catalyzed amidiniumation of alkynes and other organogold intermediates supports our proposed mechanisms. Several control experiments reveal the unexpected effects of both HOTf and substrate substituents on the choice of either a pi or sigma, pi silver activation mode and the cyclization fashion. Bis(hydroxyimidazol)ium salts were obtained through an unprecedented umpolung of propiolamides. The byproduct Ag2O as either an oxidant or silver source promotes the syntheses of N-heterocyclic carbene (NHC) precursors or Ag/NHC complexes.