Osmium(II) bipyridine (bpy) complexes containing O,O-donor ligands and X-ray crystal structure of the acetylacetonato(acac) complex [Os(bpy)2(acac)](PF6)
摘要:
The new complexes [Os-II(bpy)(2)L](PF6) [bpy = 2,2'-bipyridine; HL = acetylacetone (Hacac), trifluoroacetylacetone (Htfacac), hexafluoroacetylacetone, dibenzoylmethane or tropolone] have been prepared and the chemical oxidation of the [Os-II(bpy)(2)L](+) species (L = acac or tfacac) by aqueous S2O82- solution in the presence of (NH4)PF6 gave the reddish brown complexes [Os-III(bpy)(2)L](PF6)(2). These complexes were characterized by spectroscopic measurements and also investigated by cyclic voltammetry. The X-ray crystal structure of [Os(bpy)(2)(acac)](PF6) (1) has been determined and showed that the complex has a distorted octahedral geometry in an environment of N4O2 donors. The reactivity toward oxidation of benzyl alcohol by complex (1) using H2O2 or other co-oxidants has been studied and compared with that of the related ruthenium(II) complexes. (C) 2011 Elsevier By. All rights reserved.