Organosilyl Compounds of Germanium, Tin and Lead

The Si—Ge and Si—Sn bonds are remarkably stable, both thermally and chemically, especially when the organic substituents are aryl groups. Triphenyl( tri-phenylsilyl)germanium (m. p. 357-359°C), which does not decompose below 500°C, is not attacked by iodine in boiling trichloromethane, by oxygen in boiling xylene or by acetic acid at 140°C in a Carius tube. 

The Si—Sn bond of triphenyl(triphenylsilyl)tin (m.p. 280-286 °C) ist not broken in glacial acetic acid, although the phenyl residues are replaced stepwise by acyl residues, beginning with those on the tin atom [450] (Eq. 3.241)  

Organosilyl germanium and tin derivatives are usually prepared from the corresponding alkali metals and halogen compounds (Eq. 3.242)  

Chlorodifluorogermanium)triphenylsilane [452] is the product of germanium(II) fluoride and chlorotriphenylsilane (Eq. 3.244)  

Tetrakis(tri nethylsilyl)lead [453] (84% crystalline, decomp. 88 °C), synthesised in 1983, was the first known compound with a Si—Pb bond (Eq. 3.245)  

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