Regio- and stereoselectivity in the concatenated enyne cross metathesis–metallotropic [1,3]-shift of terminal 1,3-diyne
摘要:
Enyne cross metathesis of terminal 1,3-diynes with various alkenes afforded two products of distinctive connectivity, as the result of a uniform mode of initiation but different modes of termination events with or without metallotropic [1,3]-shift. Steric and electronic factors of the substituents on the 1,3-diynes play an important role in controlling the metallotropic [1,3]-shift of the propagating allcylidene intermediates and their regioselective trapping to the final products. (C) 2013 Elsevier Ltd. All rights reserved.
Selectivity for Alkynyl or Allenyl Imidamides and Imidates in Copper-Catalyzed Reactions of Terminal 1,3-Diynes and Azides
作者:Sourav Ghorai、Daesung Lee
DOI:10.1021/acs.orglett.0c03861
日期:2021.2.5
Copper-catalyzed reactions of terminal 1,3-diynes with electron-deficient azides to generate either 3-alkynyl or 2,3-dienyl imidamides and imidates are described. The selectivity depends on the diyne substituents and the nucleophile that reacts with the ketenimide intermediate generated from the corresponding triazole precursor. Reactions of 1,3-diynes containing a propargylic acetate afford [3]cumulenyl