Phosphine Oxide-Directed Palladium-Catalyzed B(3)–H Arylation of o-Carboranes

Abstract The selective functionalization of carboranes has received increasing research interests due to their wild applications in chemistry, life, and material sciences. Among various structurally diverse carboranes, the development of selective functionalization of the commercially available o-carborane (1,2-C2B10H12) has largely focused on the two acidic C H bonds. By contrast, research on the activation of the other ten hydridic cage B–H vertices is relatively less explored. Of particularly challenging, the most electron-deficient nature of B(3,6)-H bonds render very few synthetic methods available for their functionalization. Herein, we develop a phosphine oxide-directed palladium-catalyzed highly B(3)–H selective arylation of o-carboranes under very mild reaction conditions in short reaction time.