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The factors controlling the highly alpha-selective C-glycosylation of ribose derivatives were determined by examining the stereoselective reactions of 18 ribose analogues differing in substitution at C-2, C-3, and C-4. The lowest energy conformers of the intermediate oxocarbenium ions display the C-3 alkoxy group in a pseudoaxial orientation to maximize electrostatic effects. To a lesser extent, the C-2 substituent prefers a pseudoequatorial position, and the alkyl group at C-4 has little influence on conformational preferences. In all cases, the product was formed by stereoelectronically preferred inside attack on the lowest energy conformer.

Deuterium-labeling experiments demonstrate that the transmetalation step of the Suzuki coupling reaction of alkylboranes and alpha-iodoenones proceeds with retention of stereochemistry.

Siliranes undergo stereoselective and regioselective insertions of benzaldehyde to provide oxasilacyclopentane products. The thermal reaction (>100 °C) leads to more decomposition and side products, whereas the catalyzed variant (t-BuOK, <25 °C) proceeds more cleanly with a high degree of inversion (>95%). Treatment of siliranes with enolizable aldehydes leads to silyl enol ethers. The reaction of a silirane at high temperatures with an imine leads to reductive dimerization, presumably by way of intermediate-free silylene. The mechanism for the catalyzed insertion of benzaldehyde is discussed.

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