Table_1_Synthesis and Structures of Ruthenium Carbonyl Complexes Bearing Pyridine-Alkoxide Ligands and Their Catalytic Activity in Alcohol Oxidation.DOC

Reaction of Ru₃(CO)₁₂ with two equiv of 6-bromopyridine alcohols 6-bromopyCHROH [(R = C₆H₅ (L1); R = 4-CH₃C₆H₄ (L2); R = 4-OMeC₆H₄ (L3); R = 4-ClC₆H₄ (L4); (R = 4-CF₃C₆H₄ (L5); R = 2-OMeC₆H₄ (L6); R = 2-CF₃C₆H₄ (L7)] and 6-bromopyC(Me)₂OH (L8) in refluxing xylene afforded novel trinuclear ruthenium complexes [6-bromopyCHRO]₂Ru₃(CO)₈ (1a-1g) and [6-bromopyC(Me)₂O]₂Ru₃(CO)₈ (1h). These complexes were characterized by FT-IR and NMR spectroscopy as well as elemental analysis. The structures of all the complexes were further confirmed by X-ray crystallographic analysis. In the presence of tert-butyl hydroperoxide (TBHP) as the source of oxidant, complexes 1a-1h displayed high catalytic activities for oxidation of primary and secondary alcohols and most of oxidation reactions could be completed within 1 h at room temperature.