Synthesis and catalytic activity of novel benzimidazolinylidene- ruthenium(II) complexes

The reaction of [RuCl2(p-cymene)]2 with 1,3-dialkylbenzimidazolium salts 1a-d in the presence of a small excess of cesium carbonate yields chelated 6-arene, carbene ruthenium complexes 2a-d. All compounds were characterized by elemental analysis, NMR spectroscopy and the molecular structures of two of the complexes were determined by X-ray crystallography. The catalytic activity of RuCl2(n6-arene, n1-benzimidazolinylidene) complexes was evaluated in the direct arylation of 2-phenylpyridine with bromobenzene derivatives. © Georg Thieme Verlag Stuttgart · New York