Palladium-catalyzed intramolecular cyanoboration of allenes leading to the regioselective synthesis of β-cyanoallylboranes

Inter- and intramolecular addition of the boron-cyanide bond of cyanoboranes across a carbon–carbon double bond of allenes proceeded in the presence of palladium catalysts, affording allylboranes that bear a cyano group at the β-position regioselectively.