Palladium-Catalyzed Cross-Coupling Reactions of Carboraneswith Alkenes via Selective B–H Bond Activation

A palladium-catalyzed Heck-type cross-coupling reaction of carboranes with alkenes in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) was realized. This reaction shows good B(9) selectivity for <i>m</i>-carboranes and is also suitable for <i>o</i>- and <i>p</i>-carborane. Meanwhile, a series of mono-, di-, and trisubstituted alkenes were compatible substrates to afford the alkenylated products in 16–89% yields. The 1,2-bis(carboranyl)ethylene was first synthesized by the reaction of vinyltrimethylsilane and <i>m</i>-carborane. Further transformations of the CC bond in the product were examined by hydroboration oxidation, oxidation, hydroboration, and bromination reaction to generate corresponding B(9)-functionalized <i>m</i>-carboranes.