Molybdenum-Tungsten Mixed-Metal Trinuclear Clusters with Two Capping Oxides and Six Bridging Acetates, and Other Mixed Molybdenum-Tungsten Clusters

Mixed molybdenum-tungsten clusters of di-, tri-, tetra- and pentavalent metal ions are reviewed. Those having strong π-accepting and/or [sgrave]-donating ligands such as CO are not included. The complexes which have been prepared by the authors' group are described in more detail. These are trinuclear complexes ([MonW3-n(μ3-O)2(μ-CH3COO)6(H2O)3]2+) with the oxidation state four and dinuclear complex ([MoW(μ-O)2-(O)2(μ-N, N'-edta)]2-) with the oxidation state five. Other complexes described are dinuclear complexes of divalent metal ions (‘Mo-W quadruple bond’) and of trivalent metal ions (“Mo-W triple bond”), and trinuclear complexes with i-propoxide ligands.