Palladium-Catalyzed Selective B(3)-Esterification of o-Carboranes with CO and Alcohols

Selective functionalization of o-carboranes has received tremendous attention, specifically in the regioselective modification of the ten chemically similar BH vertices within o-carborane cage. We disclose herein a strategy for palladium-catalyzed esterification of the B(3)-H bond in o-carboranes using tungsten hexacarbonyl as a carbon monoxide source. The corresponding functionalized o-carboranes were prepared in moderate to very good yields with excellent regioselectivity.