Polyoxoanion-supported, atomically dispersed cyclooctadieneruthenium(II) complexes

The cation [Ru(C8H12)]2+ was supported on [P3O9]3–, [V4O12]4– and [Nb2W4O19]4– polyoxoanions. All the complexes were stable in air and were characterized by elemental and thermogravimetric analysis, IR, 1H, 13C and 31P NMR spectroscopy. The crystal and molecular structure of [NBu4][Ru(C8H12)(MeCN)-(P3O9)]·Et2O has been determined [space group C2/c, a= 38.359(4), b= 9.907(5), c= 26.437(3)Å, β= 127.720(4)°]. Ruthenium(II) is octahedrally co-ordinated to the two C8H12-diene groups, to one acetonitrile molecule and through three O atoms to the P3O93– ligand. In the case of [Ru(C8H12)(MeCN)2-(HV4O12)– and [Ru(C8H12)(MeCN)2(V4O12)]2– where a bidentate co-ordination to the polyanion is observed, two MeCN molecules are co-ordinated by Ru, resulting in the 18-valence-electron configuration. The [Nb2W4O19]4– anion behaves differently: its reaction with [RuCl(C8H12)(MeCN)3]PF6 leads to a product which, on the basis of IR, elemental analysis and the literature, we formulate as [NBu4]3[{RuCl(C8H12)(MeCN)}5(Nb2W4O19)2]·3H2O. In this case two Nb2W4O194– anions are probably linked, face to face, by five organometallic centres.