Synthesis of Nitrogen Heterocycles by Electrochemical Radical Cyclization Using an Arene Mediator

摘要

Radical cyclization is a useful method for synthesis of cyclic compounds.Carbon radicals are usually generated from the corresponding organic halides by their reaction with AIBN-Bu_3SnH.However,there are several drawbacks in this method: the toxicity of tin compounds and the difficulty in isolation of products due to contamination of R_3SnX.On the other hand,electrochemical reduction of alkenyl or aryl halides using a Ni(II) catalyst,oxygen mediator,and arene mediator has been reported to generate the corresponding radicals,which afford the cyclization products (1).