Reaction of [Ti(cp)2(AsF6)2](cp =η-C5H5) toward S4N4 and Se4N4: identification in solution of [Ti(cp)2(S4N4)][AsF6]2; synthesis and characterization of [Ti(cp)2F(AsF6)], [Ti(cp)2F2]·AsF3 and [Ti(cp)F3]·AsF3

Abstract

The reaction of [Ti(cp)₂(AsF₆)₂]2(cp =η-C₅H₅) with S₄N₄ in liquid sulphur dioxide gives [Ti(cp)₂F(AsF₆)]4 and S₄N₄·AsF₅5. The new complex 4 can be prepared in quantitative yield from [Ti(cp)₂F₂]1 and AsF₅. Proton, ¹⁴N and ¹⁹F NMR spectroscopy reveals that SO₂ solutions of 2 and S₄N₄ or 4 and 5 contain [Ti(cp)₂(S₄N₄)][AsF₆]₂3. In contrast Se₄N₄ is oxidized by 2 and leads to [(SeNSeNSe)₂][AsF₆]₂, N₂, AsF₃ and 1. Complex 1 forms a stable adduct with AsF₃, [Ti(cp)₂F₂]·AsF₃, which was characterized by ¹H NMR, IR and mass spectroscopy and elemental analysis. The monocyclopentadienyl analogue [Ti(cp)F₃]·AsF₃ can also be prepared in quantitative yield from [Ti(cp)Cl₃] and Ag[AsF₆].