Synthesis and reactivity of the bulky germanium(IV) trisamide complexes BrGe[N(SiMe3)2]3 and LiGe[N(SiMe3)2]3: X-ray crystal structures of BrGe[N(SiMe3)2]3 and [(Me3Si)2N]3Ge(CH2CH2CH2CH3)

The bulky germanium(IV) trisamide complex BrGe[N(SiMe3)2]3 has been prepared and structurally characterized. Reaction of this material with nBuLi resulted in [(Me3Si)2N]3Ge(CH2CH2CH2CH3), which has also been structurally characterized, but no reaction with lithium metal was observed in the attempted preparation of LiGe[N(SiMe3)2]3. However, analytically pure LiGe[N(SiMe3)2]3was prepared by the reaction of 3 equivalents of LiN(SiMe3)2 with GeI2. Evidence is presented that this germyllithium reagent is a major by-product in the synthesis of Ge[N(SiMe3)2]2 when the latter reagent is obtained from GeCl2 · (dioxane) prepared by the method of Kolesnikov et al. Reaction of the germyllithium reagent with 2,6-diphenylphenol yields the mixed Ge/Li cage complex [Li(μ2-OC6H3Ph2-2,6)3Ge], which had originally been obtained serendipitously via the reaction of 2,6-diphenylphenol with Ge[N(SiMe3)]2.