86782-93-6Relevant articles and documents
Preparation of W2Cl84- and several of its derivatives
Schrock, Richard R.,Sturgeoff, Lynda G.,Sharp, Paul R.
, p. 2801 - 2806 (2008/10/08)
The sodium amalgam reduction of WCl4 in tetrahydrofuran in the presence of a tertiary phosphine (L = PMe3, PBu3, PMe2Ph, PMePh2) produces a family of compounds of the type W2Cl4L4, which contain a tungsten-tungsten quadruple bond. W2Cl4(dmpe)2 and W2Cl4(dppe)2 must be prepared by the reaction between W2Cl4(PBu3)4 and dmpe or dppe. In the absence of phosphine, WCl4 can be reduced to W2Cl6(THF)4. W2Cl6(THF)4 reacts with phosphine to produce W2Cl6L4, and W2Cl6L4 can be reduced cleanly to W2Cl4L4. In the absence of phosphine W2Cl6(THF)4 can be reduced to deep blue Na4(THF)xW2Cl8. Several other derivatives such as Na4(TMEDA)4W2Cl8 have also been prepared. All derivatives that contain the W2Cl84- ion decompose within a few minutes at 25°C in solvents in which they dissolve. Na4(THF)xW2Cl8 reacts rapidly with phosphine to produce W2Cl4L4, with 6-methyl-2-hydroxypyridine in the presence of triethylamine to produce W2(mhp)4, and with pivalic acid in the presence of triethylamine to produce W2(O2CCMe3)4. We have shown that complexes of the type W2Cl4L4 can be oxidized readily to monocations. An attempt to prepare W2(O2CCH3)4 from W2Cl4(PBu3)4 and acetic acid also led to oxidation of the metal to give W3O3Cl5(O2CCH3)(PBu 3)3.
