Catalyst‐ and Oxidant‐Free Electrochemical Halogenation Reactions of 2<i>H</i>‐Indazoles with NaX (X=Cl, Br)
Xin Liu, Zengzhi Wu, Chenglong Feng, Wenlu Liu, Meichao Li, Zhenlu Shen
Abstract
Abstract An environmentally friendly and highly efficient electrochemical method has been developed for halogenation of 2 H ‐indazoles with cheap and commercially available NaX (X=Cl, Br) in the absence of metal catalysts and oxidants. Notably, this electrochemical process exhibits a broad substrate scope and high functional‐group compatibility. A variety of 2 H ‐indazoles are compatible with this transformation to give the corresponding products in modern to excellent yields. Also, this practical protocol avoids using external expensive supporting electrolytes. Last but not least, the procedure was carried out in an undivided cell at constant current condition under air atmosphere.