Aluminium complex-catalysed hydroboration of alkenes and alkynes

Abstract

We demonstrate an efficient method for the hydroboration of terminal alkenes or alkynes with pinacolborane (HBpin) using the aluminium catalyst, [κ²-{Ph₂P(=Se)NCH₂(C₅H₄N)}Al(CH₃)₂] (1), supported by a functionalized amidophosphine ligand under mild and solvent-free conditions to afford the corresponding alkyl and alkenyl boronate esters in high yield. This protocol involves the chemoselective formation of an anti-Markovnikov product exclusively. Both terminal alkenes and alkynes bearing a wide array of electron-withdrawing and donating functional groups can easily be converted to the corresponding product through the formation of aluminum hydride as an active catalytic species.