Palladium catalyzed cross-couplings of trans-vinylboranes with alkyl bromides: a reversed-polarity alternative to B-alkyl Suzuki reactions

Abstract

A variety of trans-alkenyl-9-BBN derivatives have been prepared in situ and then coupled with alkyl bromides by utilizing palladium catalysis with the electron-rich and sterically encumbered tricyclohexylphosphine ligand. To prepare the needed organoboranes, three protocols have been used, with the most adopted being the one involving double hydroboration followed by the Soderquist dehydroborylation reaction. Overall, this approach constitutes a reversed-polarity alternative to the B-alkyl Suzuki protocol.