A Stable Homoleptic Divinyl Tetrelene Series.

The synthesis of the new bulky vinyllithium reagent ( IPr=CH)Li, ( IPr=[(MeCNDipp) C]; Dipp=2,6-iPr C H ) is reported. This vinyllithium precursor was found to act as a general source of the anionic 2σ, 2π-electron donor ligand [ IPr=CH] . Furthermore, a high-yielding route to the degradation-resistant Si precursor IPr⋅SiBr is presented. The efficacy of ( IPr=CH)Li in synthesis was demonstrated by the generation of a complete inorganic divinyltetrelene series ( IPrCH) E: (E=Si to Pb). ( IPrCH) Si: represents the first two-coordinate acyclic silylene not bound by heteroatom donors, with dual electrophilic and nucleophilic character at the Si center noted. Cyclic voltammetry shows this electron-rich silylene to be a potent reducing agent, rivalling the reducing power of the 19-electron complex cobaltocene (Cp Co).