Synthesis and characterization of bidentate NHC-Pd complexes and their role in amination reactions

WOS: 000287059400026The new well-defined and air-stable ortho-xylyl-linked N-heterocyclic carbene (NHC) Pd complexes (2a-d) have been synthesized and characterized by elemental analysis, H-1 NMR, C-13 NMR, IR spectroscopy, and single crystal X-ray diffraction studies. The palladium atom in the complex 2a lies on a crystallographic mirror plane and can be described as having a square-planar coordination environment with the carbene atoms of the benzimidazole rings of the ligand occupying two coordination sites in cis positions. Two further coordination sites are occupied by chloride ligands. The benzimidazole rings are connected to each other by an ortho-xylyl bridge. The catalytic activity of these palladium complexes has been tested in the coupling reactions of various N-containing substrates with bromobenzene. A preliminary catalytic study shows that the bis(NHC)-Pd complexes are highly active in the Buchwald-Hartwig amination reaction. (C) 2010 Elsevier Ltd. All rights reserved.Technological and Scientific Research Council of Turkey TUBITAK-BOSPHORUS (France)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [109T605]; Inonu UniversityInonu University [I.U. B.A.P: 2009/10]This work was financially supported by the Technological and Scientific Research Council of Turkey TUBITAK-BOSPHORUS (France) [109T605] and Inonu University Research Fund (I.U. B.A.P: 2009/10)