Samarium(III) catalyzed synthesis of alkenylboron compounds via hydroboration of alkynes

The homoleptic lanthanide complex Sm[N(TMS)2]3 is an efficient rare-earth catalyst for the hydroboration of alkynes to the corresponding alkenylboron compounds. Practical applications were demonstrated in a gram-scale synthesis and further transformations of an alkenylboron ester to a series of functional compounds. Isotopic labeling experiments, 1H NMR-monitoring and kinetic studies were conducted to elucidate the reaction mechanism.