Electrochemical regioselective C-H selenylation of 2-indazole derivatives.

Selenium-substituted heteroarenes are biologically active compounds and useful building blocks. In this study, we have developed a metal- and oxidant-free, environmentally friendly protocol for the regioselective selenylation of 2-indazole derivatives by an electrochemical strategy. A number of selenylated 2-indazoles with a wide range of functional groups have been synthesized in moderate to good yields under mild and environment-friendly reaction conditions.