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 electrophiliccyclization 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
A Simple and Efficient Copper-Catalyzed Synthesis of N-Alkynylimidazoles
作者:Jun Wu、Zhi-Cai Shang、Man-Gang Wang
DOI:10.1055/s-0031-1290340
日期:2012.3
A simple and efficient method for the synthesis of N-alkynylheteroarenes from 1,1-dibromo-1-alkenes was developed via a copper-catalyzed cross-coupling reaction. Generally superior yields and functional-group tolerance were obtained with TMEDA as ligand using imidazole and benzimidazole substrates in dioxane. N-alkynylimidazoles - 1,1-dibromo-1-alkenes - copper - cross-coupling reaction - alkynylation