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Regiocontrollable B(2/3)-H Alkenylation of nido-Carboranes
Ping Li1, Jiayi Yang1, Jiayi Zeng1
1School of Chemistry and Chemical Engineering, Hainan University, Haikou 570228, China.
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.
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