A Highly Active Catalyst System for Suzuki-Miyaura Coupling of Aryl Chlorides

A series of new Pd(II) complexes with simple structures were designed and synthesized for Suzuki-Miyaura coupling reactions of aryl chlorides. The new Pd(II) complexes contain bidentate amine ligands, and their structures were characterized by single-crystal X-ray diffraction. They are highly efficient for Suzuki-Miyaura coupling reactions of aryl chlorides with low catalyst loadings (0.01 mol %) in aqueous media at room temperature. Two possible reaction pathways involving a Pd-II/0/II and a Pd-II/IV/II catalytic cycle are proposed, and the mechanism was further investigated using density functional theory (DFT) calculations.