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

Abstract

Anionic nido-carboranes, as open-cage analogues of closo-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 exo-cage B–H activation reactions of nido-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 nido-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 exo-cage B11–H vertex in nido-carboranes.