Aerobic oxidative dehydrogenation of coordinated imidazoline units of pincer ruthenium complex
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.
Aerobic oxidative dehydrogenation of coordinated imidazoline units of pincer ruthenium complex
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.