摘要:
                                A new pincer ruthenium complex (1; [RuL1(tpy)](PF6); L-1 = 1,3- di(2-imidazoline-2-yl) benzene, tpy = 2,2': 6',2 ''- terpyridine) having a kappa(NCN)-N-3 pincer ligand with two imidazoline units and related ruthenium complexes were synthesized and characterized. The imidazoline units of 1 were oxidized in air to give an imidazole-ligated pincer complex (2; [RuL2(tpy)](PF6); L-2 = 1,3- di(2-imidazolyl) benzene). Results of the H-1 NMR spectroscopic and cyclic voltammetric studies of the complexes indicate that the sigma-donor character of the pincer ligand of 1 induces the Ru-promoted oxidative dehydrogenation of coordinated imidazoline moieties to imidazole units with oxygen in air. (C) 2007 Elsevier B.V. All rights reserved.