Highly efficient amine-based catalytic system for room temperature Suzuki–Miyaura reactions of aryl halides with arylboronic acids



An in situ-generated catalytic system based on PdCl2 and primary amine-based ligand exhibited excellent activity (up to 98% isolated yield) in the Suzuki–Miyaura cross-coupling reactions of aryl bromides with arylboronic acids in water, at room temperature, without any additive. The efficiencies of the ligands follow the order: (C6H5)3CNH2 > C6H5CH2 NH2 > C6H5 NH2 > C6H11 NH2, which is in accordance with the palladacycle forming capacity of the respective ligands. Moderate-to-good yields (up to 78% isolated yield) of the coupling products were also obtained with less reactive aryl chlorides as substrates at room temperature in isopropanol using an alternative protocol based on Pd(OAc)2 and (C6H5)3CNH2. Copyright © 2011 John Wiley & Sons, Ltd.