Electrophilic Cyclization of<i>N</i>-Alkynyl-2-(organochalcogen)imidazoles: An Alternative Access to Imidazo[2,1-<i>b</i>]chalcogenazoles
作者:Tamíris B. Grimaldi、Benhur Godoi、Juliano A. Roehrs、Adriane Sperança、Gilson Zeni
DOI:10.1002/ejoc.201201692
日期:2013.5
multifunctional imidazo[2,1-b]chalcogenazoles through electrophilic cyclization of N-alkynyl-2-(organochalcogen)imidazoles. The cyclization reaction proceeded cleanly and smoothly under mild reaction conditions in the presence of air. The methodology was highly regioselective: In a competition between the chalcogen and oxygen atoms, only S-, and Se-heterocycles were obtained. The resulting imidazo[2,1-b]chalcogenazoles
我们在此介绍了通过 N-炔基-2-(有机硫属元素)咪唑的亲电环化实际合成多功能咪唑并 [2,1-b] 硫属元素唑。在温和的反应条件下,在空气存在下,环化反应进行得干净、顺利。该方法具有高度区域选择性:在硫属元素和氧原子之间的竞争中,仅获得 S-和 Se-杂环。由此产生的咪唑并[2,1-b]硫属元素唑被证明是通用的前体,用于通过铜催化与芳烃和烷硫醇的交叉偶联反应合成更高功能化的咪唑硒唑,从而以良好的产率获得乌尔曼型产品。