Azo-azomethine based palladium(II) complexes as catalysts for the Suzuki-Miyaura cross-coupling reaction

Seven azo-azomethine ligands (2-8) have been synthesized from the reaction of (E)-5-((4-chlorophenyl) diazenyl)-2-hydroxybenzaldehyde with different aniline derivatives. Ligand structures were characterized by the combination of IR, UVeVisible spectroscopy, C-13 NMR, H-1 NMR and elemental analyses. The mononuclear Pd(II) complexes of these azo-azomethine compounds were prepared with sodium tetrachloropalladate(II) and characterized. According to the UVevisible, FTIR, elemental analyze and HRMS data, the Pd (II) complexes 9-15 are formed by the coordination of N, O atoms of the ligands. Solid state structures of 2, 6 and 7 were determined by single crystal X-ray diffraction studies. Also, Pd(II) complexes were used catalysts for Suzuki-Miyaura coupling reactions of phenylboronic acid with aryl bromide in aqueous media. When the catalytic studies were evaluated, it was found that all of the complexes were suitable for the Suzuki-Miyaura cross-coupling reaction. (c) 2020 Elsevier B.V. All rights reserved.