Organolead chemistry. Part 5. Reactions of bis(η-cyclopentadienyl)lead(II) with metal halides and with unsaturated compounds

Abstract

Bis(η-cyclopentadienyl)lead(II) acts as a Lewis base and forms a thermally stable, polymeric, complex with BF₃. However, with weaker Lewis acids (BMe₃, BPh₃, or Al₂Me₆) no adducts are formed and with many metal halides (BCl₃, Al₂Cl₆, TiCl₃, VCl₃O, or [TaMe₃Cl₂]) cyclopentadienyl-for-halide exchange reactions occur. The new compounds [TaMe₃(η-C₅H₅)Cl] and a compound tentatively formulated as [TaMe₃(η-C₅H₅)H] have been prepared in this way. The compound Pb(η-C₅H₅)₂ also gives adducts Pb(η-C₅H₅)₂·0.5tcne. Pb(η-C₅H₅)₂·tcne, and Pb(η-C₅H₅)₂·tcnq with tetracyanoethylene (tcne) and with 7,7,8,8-tetracyanoquinodimethane (tcnq). The structures of these compounds are discussed, and the presence of tcne^2– or tcnq^2– is deduced.