Germanium, trimethyl-, compound

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 ... 

The shortest Ge—H bond yet found in an organogermane occurs in the recently reported complex hydride [(CH3)3Si]2CH 2(OC2H5)GeH (118). The shortness of the Ge—H bond (1.46 A) must, at least in part, arise from the hybridization demands of the electronegative ethoxy group. Distortions in the tetrahedral environment about the germanium (Table I) arise from the steric requirements of the bis(trimethyl-silylmethyl) moieties, while the authors attribute to the same source the stability of this compound with respect to the reductive elimination of alcohol normally observed (127). 

Compounds like l,4,7-trimethyl-l,4,7-triazacyclononane (L ) and l,3,5-trimethyl-l,3,5-triazacyclohexane (L ) are useful ligands in germanium chemistry. Reactions of with GeCU and with GeBr4 both in the ratio 1 1 in acetonitrile solution form ionic compounds with GeX3+ cations [GeCl3(L )]Cl3 MeCN and [GeBr3(L )]Br3 MeCN. Acetonitrile is trapped in the lattice as solvate molecules. ... 

Electron diffraction investigations of trimethyl silylcyclopentadiene ), (CH3)3Si(CsH5), and the analogous germanium ) and tin ) compounds have shown that these compounds contain cr-bonded cyclopentadienyl rings. Because of the low symmetry of these compounds only a limited number of parameters could be refined the remainder were fixed at assumed values. Nevertheless, it was concluded that the cyclopentadienyl rings in these compounds were nonplanar, in contrast to cyclopentadiene itself, which is planar ). 

Compounds containing Silicon-, Germanium-, Tii, and Lead-Nitrogen Bonds.—Molecular nitrogen is reductively silylated by MeaSiCl and lithium metal in the presence of a transition-metal catalyst to give tris(trimethyl-silyl)amine [reaction (101)]. Variable-temperature n.m.r. spectra for a number of compounds containing Si—N bonds in which potentially diastereo-... 

Miscellaneous Physical Measurements.— In this section are included physical data not previously mentioned. Binding energies of silicon, germanium, tin, and lead compounds have been determined by X-ray photoelectron spectros-copy. The enthalpies of formation of several trimethyl-silyl, -germyl. 

Side reactions are the formation of dehydration of the pendent 2-hy-droxyethyl ester to result in pendent vinyl ester groups. These can further react under the ejection of acetaldehyde. Suitable catalysts are germanium compounds, such as germanium oxide, zinc acetate, manganese acetate, or a combination of antimony trioxide and trimethyl phosphate. ... 

The data, which are relatively self-consistent regardless of the method, indicate that acylsilanes and acylgermanes are significantly more basic than their carbon analogs for both trimethyl and triphenyl derivatives. In each case, the silicon compound is slightly more basic than the germanium compound. 

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