Synthesis and characterisation of cationic bis(cyclopentadienyl)tungsten(IV) complexes containing alkyl, chloride and hydride ligands

Abstract

The cationic complexes [W(η-C₅H₅)₂R(NCMe)][PF₆](R = Et or H), [W(η-C₅H₅)₂Me(NCR′)][BF₄] and [W(η-C₅H₅)₂Cl(NCR′)][BF₄](R′= Me or Ph) have been prepared and characterised by ¹H and ¹³C NMR and IR spectroscopy, and by X-ray crystallography in the case of [W(η-C₅H₅)₂Et(NCMe)][PF₆]. The complex [W(η-C₅H₅)₂H(NCMe)][PF₆] is unstable in solution at room temperature, decomposing slowly to yield the dinuclear C–H activation product [{W(η-C₅H₅)(µ-η¹:η⁵-C₅H₄)(NCMe)}₂][PF₆]₂ as demonstrated by NMR spectroscopy and X-ray crystallography.