A Direct Synthesis of Selenophenes by Cu-Catalyzed One-Pot Addition of a Selenium Moiety to (E,E)-1,3-Dienyl Bromides and Subsequent Nucleophilic Cyclization

An efficient protocol for the synthesis of selenophenes and selanyl selenophenes has been achieved by a simple one-pot reaction of 1,3-dienyl bromides and 1,3-dienyl-gem-dibromides respectively with KSeCN catalyzed by CuO nanoparticles. Several aryl, alkenyl, heteroaryl, and alkyl substituted selenophenes were obtained with a broad array of functional group tolerance. This is found to be a general methodology for chalcogenophenes being effective for the synthesis of thiophenes too.