Palladium catalyzed Suzuki cross-coupling reactions using N, O-bidentate ligands

Abstract

Palladium-catalyzed Suzuki cross-coupling reactions employing Schiff-bases as ligands toward a series of substituted arylbromides and boronic acids were pursued. In the presence of a N, O-bidentate ligand, 2-[1-(2,4,6-trimethyl-phenylimino)-ethyl]-phenol 5 , the catalytic reactions could be carried out efficiently at room temperature with a wide array of arylbromides, even with electronically deactivated arenes. A deprotonated 5 , 5′ , chelated palladium acetate complex, [ 5′ Pd(II)(OAc)(solv)] 8 , was proposed as a precursor of a genuine catalytically active species.