Germanium halides formation

Addition of an excess of organolithium or organomagnesium reagents to germanium halides results in the deplacement of the halide ions and the formation of tetra-alkyl and -arylgermanium compounds. Representative examples of these reactions are shown in equations 4 and 5, respectively. 

Common methods for the formation of germanium-carbon bonds, including reactions of germanium halides with organolithium or Grignard reagents, are still used and have yielded some interesting new compounds. In addition, several novel methods for Ge-C bond formation have also been developed since the field was last reviewed. 

Formation of Germanium-Transition and Inner Transition Metal Bond 5.8.4.3. from Germanium Halides... 

While this accounts satisfactorily for the behavior of silicon compounds, and suggests again, as in the acylmetalloids, that silicon-oxygen bond formation is a powerful driving force governing the reactions of these compounds, the behavior of j8-ketones with germanium halides is not explained, and appears to require a four-center transition state. 

The transmetalation of trimethylsilylphosphanes with germanium and tin halides is a useful way to prepare compounds with P—Ge and P—Sn bonds by simple chlorosilane elimination. The reverse reaction, i. e. formation of P—Si bonds by chlorosilane cleavage of germyl- and stannylphosphanes has not yet been reported. Recently, we observed that hexachlorodisilane "transsilylates di-r-butyl(trimethyl-silyl)phosphane 1 much faster than tetrachlorosilane to give trichlorosilylphosphane 2 ... 

Nucleophilic carbenes have been reported to react with Eewis acidic group 14 complexes with the isolation of neutral or ionic compounds via simple adduct formation or displacement of a halide ion. > The range of carbene complexes of silicon, germanium, tin, and lead, as well as some related cyclopropenylidene complexes are described below. 

X = Ln, Tl, M = Sn, Pb show that the complexes comprise octahedral [FgM] ions and isolated fluoride ions rather than any seven-coordinate metals. Other tin fluorides have more complex structures, such as the dimeric [Su2F4] ion present in [NH4]4[Sn2F4](N03)2" and in mixed halide complexes, such as Cs2SngBr3Fii which has in the crystal three distinct tin sites, each of which has close contacts with the fluoride ions only." The electronic effects of adduct formation of halides of germanium(IV) and tin(IV) have been reviewed with particular reference to the geometry of the complexes formed. 

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