Iodine-Catalyzed Selenylation of 2H-Indazole.

A metal-free, environmentally friendly protocol for the arylselenylation of 2H-indazole has been developed using a catalytic amount of I2 under ambient conditions. A number of 3-(phenylselanyl)-2H-indazoles with wide functional group tolerance have been synthesized in good yields at room temperature. Mechanistic studies suggest that the reaction possibly proceeds through an ionic pathway.