An N-Heterocyclic Silylene-Stabilized Digermanium(0) Complex

The synthesis of an N-heterocyclic silylene-stabilized digermanium(0) complex is described. The reaction of the amidinate-stabilized silicon(II) amide [LSiN(SiMe3)(2)] (1; L=PhC(NtBu)(2)) with GeCl2 center dot dioxane in toluene afforded the Si-II-Ge-II adduct [L{(Me3Si)(2)N}Si -> GeCl2] (2). Reaction of the adduct with two equivalents of KC8 in toluene at room temperature afforded the N-heterocyclic carbene silylene-stabilized digermanium(0) complex [L{(Me3Si)(2)N}Si -> Ge=Ge <- Si{N(SiMe3)(2)}L] (3). X-ray crystallography and theoretical studies show conclusively that the N-heterocyclic silylenes stabilize the singlet digermanium(0) moiety by a weak synergic donor-acceptor interaction.