Rhodium(iii)-catalyzed dehydrogenative dialkenylation of the monocarba-closo-decaborate cluster by regioselective B-H activation.

closo-Boranes and closo-carboranes, clusters with a closed-cage structure, exhibit remarkable inertness and are unique components of products with applications in areas such as medicinal chemistry, fluorescence and materials science. Herein, we report the first transition metal-catalyzed functionalization of the mono-closo-decaborate cluster [1-CB9H10]- by regioselective B-H activation. Using terminal alkenes bearing a wide range of functional groups, dehydrogenative coupling under mild conditions leads to B2/3-dialkenylated products, as verified by X-ray crystallography and NMR studies. This substitution pattern has not been accessible by other methods and enables the straightforward synthesis of new derivatives of the {CB9} cluster.