The synthesis of β-and γ-hydroxy-and keto-silanes is described, together with that of their carbon analogues. Unlike the α-isomers, the hydroxysilanes do not rearrange to silyl ethers, and the ultraviolet spectra of the silyl ketones is essentially the same as those of the carbon analogues, and unlike that of α-silyl ketones. β-Silyl ketones have a carbonyl-stretching frequency midway between that of ordinary ketones and α-silyl ketones. These effects are ...