Regiocontrollable B(2/3)-H Alkenylation of -Carboranes.

Anionic -carboranes, as open-cage analogues of -carboranes with strong hydrophilicity and higher potential in the development of biomedicines, have been notably more challenging because of their strong interaction with transition metals. While the -cage B-H activation reactions of -carboranes have been widely studied, there are few reports on the direct functionalization of B-H bonds located on a closed polyhedral sphere. Here, we report an efficient palladium-catalyzed regioselective B(2/3)-H alkenylation of -carboranes with various alkenes and alkyne coupling partners, enabled by 3-methylpyridine directing groups, to achieve a regiocontrollable functionalization of B(2/3)-H vertices over highly reactive -cage B11-H vertex in -carboranes.