Carbon-boron bond cross-coupling reaction catalyzed by -PPh₂containing palladium-indolylphosphine complexes

This study describes the application of indolylphosphine ligands with a diphenylphosphino moiety to the palladium-catalyzed borylation of aryl chlorides. The combination of palladium metal precursor with PPh2-Andole-phos, which comprises an inexpensive -PPh2group, provides highly effective catalysts for the borylation of aryl chlorides. A range of functional groups such as -CN, -NO2, -CHO, -COMe, -COOMe, and -CF3was compatible, and the catalyst loading down to 0.025 mol % of Pd can be achieved. The Pd/PPh2-Andole-phos system is able to catalyze both borylation reaction and Suzuki-Miyaura coupling reaction in a one-pot sequential manner for the direct synthesis of biaryl compounds in excellent yields.