Synthesis and Structural Characterization of ‘Non-VSEPR’ Structures of Oxo-Tungsten Complex

The crystal structure of [(CH3)4N]4 [WOCl4F][WO3Cl4] was determined by single crystal x-ray diffraction technique. The crystal is monoclinic, space group C 2/m, with a= 28.23(10) Å, b= 11.60(4) Å,c= 13.48(5) Å, β=118.43(7)°, V= 3886(2)Å3, Z=4. The structure was solved by direct methods and refined by least-squares methods to a final R = 0.0512 for 3825 observed reflections with I>2σ(I). In crystal there are two crystallographic distinct anions, both with cis geometry; the O-W-F and O-W-O angles are 97.5(3)° and 103.1(3) ° respectively. All structures are cis configurations that confirm a preference for angles below 90° and 180° between cis and trans σ-donor ligands, respectively