Convenient preparation of cyclo-eicosasulphur (S20) from bis(η-cyclopentadienyl)(pentasulphido)titanium(IV)

Abstract

High-pressure liquid chromatographic analysis of stoicheiometric mixtures of [Ti(cp)₂S₅](cp =η-cyclopentadienyl) and SO₂Cl₂ in CS₂ solution has revealed the presence of S₁₀, S₁₅, S₂₀, and S₂₅ in order of decreasing concentration. The compound S₂₀ has been isolated in 8% yield and a reaction mechanism explaining its formation is proposed. An improved synthesis (88% yield) of [Ti(cp)₂S₅] from [Ti(cp)₂Cl₂] is also reported.