Tetrakis(di- tert -butylmethylsilyl)digermene: Synthesis, Structure, Electrochemical Properties, and Reactivity: Tetrakis(di- tert -butylmethylsilyl)digermene: Synthesis, Structure, Electrochemical Properties, and Reactivity

The tetrasilyl-substituted digermene ((Bu2MeSi)-Bu-t)(2)GeGe((SiMeBu2)-Bu-t)(2) 1 was prepared by the reduction of the readily available 1,1-dichlorogermane ((Bu2MeSi)-Bu-t)(2)GeCl2 with potassium graphite. Compound 1 is a rather unusual example of a digermene featuring planar geometry at the doubly bonded germanium atoms, on the one hand, and an extraordinarily twisted GeGe bond, on the other hand, caused by the electronic and steric factors of the bulky sigma-donating silyl substituents. Although it maintains the structural integrity of its double bond in solution, 1 revealed reactivity that is not characteristic of the >GeGe< bond but is typical for germylenes >Ge: upon reaction with nucleophilic reagents (isocyanide, orthoquinone). Unlike common alkenes, 1 affords stable cation and anion radicals generated by cyclic voltammetry.