MESITYL OXO MOLYBDENUM AND TUNGSTEN COMPO UNDS - 3 - REACTIONS OF WOCL4 WITH MESITYL GRIGNARD-REAGENT - X-RAY CRYSTAL-STRUCTURES OF [CLMG(THF)(4)(OWCL4(THF))], [MG(THF)(4)(OWCL4(THF))(2)], AND WOMES(3)(THF)(2)

The reaction of WOCl4 with MesMgBr (1:1) in tetrahydrofuran (THF) proc eeds via reduction to tungsten(V), which can be isolated as [MgX(THF)4 ].[WOCl4(THF)] (2) and by elimination of MgX2 in form of [Mg(THF)(4){O WCl4(THF)}(2)] (3). The reaction of WOCl4 with MesMgBr in the molar ra tio 1:4 yields after reduction [WOMes(3)(THF)] THF (4). All complexes are characterized by X-ray structure analyses. In 2 and 3 [WOCl4(THF)] (-) anions are linked via their oxo ligands to the magnesium ions. 4 h as a distorted trigonal bipyramidal coordination sphere.