New phenylene bridged binuclear bis (imino-quinolyl) palladium (II) complexes: Synthesis, characterization and Heck reactions

Two new phenylene bridged binuclear bis (imino-quinolyl) palladium (II) complexes were prepared from the reaction of the ligand 1,4-bis (imino-quinolyl) benzene, L1 with either Pd (cod) Cl2 or Pd (cod) ClMe. The molecular structure of L1 was confirmed by single crystal X-ray diffraction analysis. The structure shows two planar molecules (A and B) in the asymmetric unit. The complexes were evaluated as catalysts for Heck coupling reactions of methyl and butyl acrylate with iodobenzene, and showed high activity. The reactions proceeded at a faster initial rate and there was good selectivity for the formation of the trans- isomers.