Synthesis, structure and characterization of a new tetrameric tungsten-oxo complex [WO2Cl2(THF)]4

WOCl4 reacts with (Me3Si)(2)O and excess THF to give [WO2Cl2(THF)](4) (1), a new tetrameric tungsten(VI)-oxo complex, which was characterized and crystal structure was determined by X-ray crystallography. Complex 1 has a roughly square planar tetranuclear structure bridged by mu-oxo ligands. Each tungsten atom is coordinated by two bridging oxygens, one terminal oxygen, two axial chlorine atoms and one equatorial O-bonded THF ligand. One of the two mu-oxo ligands is similar to the terminal oxygen atom and the other one is similar to the coordinated oxygen atom of the THF ligand, respectively, which confirmed a previous proposal. Four WO3Cl2(THF) octahedral are associated by sharing corners. Complex 1 is different from three known tetrameric tungsten analogues in its structural arrangement and properties. (C) 2009 Elsevier B. V. All rights reserved.