Tetranuclear assembly of palladium(II): Catalyst for C-C coupling reactions

Abstract

The 2-((2-benzylamino)phenyldiazenyl)phenol, H2OL [where H 2OL = ArOHN = NC6H4N(H)CH2(C 6H5); Ar = C6H5 (for H2OL1), p-MeC6H4 (for H2OL2) or p-ClC 6H4 (for H2OL3)], ligands were prepared by the reaction of the appropriate 2-((2-hydroxyaryl)azo)anilines with benzyl bromide. The reactions of Na2PdCl4 with H 2OL afforded tetranuclear Pd(II) complexes of the composition [Pd(OL)]4. The ligands bind palladium(II) in a tridentate (N, N, O) fashion. The X-ray structure of [Pd(OL1)]4 was determined to confirm the characterization. The newly synthesized [Pd(OL1)] 4 complex was utilized as a catalyst for the Suzuki and Heck reaction for a variety of substrates. © 2013 Elsevier Ltd. All rights reserved.