Synthesis, isolation and spectroscopic characterization of Dawson polyoxotungstate-supported, organometallic complex, [{(C6H6)Ru}P2W15V3O62](7-): The two positional isomers

摘要

The Dawson polyoxotungstate (POM)-based, organometallic ruthenium(II) complex, [{C6H6)Ru)P2W15V3O62](7-) was synthesized as two materials, i.e. 1 center dot 2Bu(4)NCl and 1 center dot 2Bu(4)NCl (1 = (Bu4N)(7)[{(C6H6)Ru)P2W15V3O62]), which contained two positional isomers a and b as major or minor species. In isomer a with the overall C-s symmetry, the (C6H6)Ru2+ group was supported on one vanadium(V) octahedral site (two V-O-V bridging oxygens and one O=V terminal oxygen) of the three edge-shared vanadium(V) octahedra (V-3 site, B-site) in the Dawson POM-support [1,2,3-P2W15V3O62](9-), whereas in the other isomer b with the overall C-3v symmetry, the (C6H6)Ru2+ group was supported on the center of the V-3 site in the Dawson POM-support. Material 1 - 2Bu(4)NCl was prepared by a stoichiometric reaction in CH2Cl2 at ambient temperature of the Dawson POM-support (Bu4N)(9)[1,2,3-P2W15V3O62] with the precursor [(C6H6)RuCl2](2), whereas material 1 - 1Bu(4)NCl was prepared by a stoichiometric reaction in CH3CN under refluxing conditions. The temperature-varied P-3 NMR spectra revealed that b was thermodynamically more stable than a. (C) 2006 Elsevier B.V. All rights reserved.