The Chemistry of Chlorosilyl Enolates 3.: Variation of the Silyl Group and the Effect on Rate and Enantiomeric Excess of Acetate Aldol Additions

Article abstract of DOI:10.1055/s-1997-1543

The rales of reaction of the silyl ketene acetals CH₂=C(OMe)OSiCl₂R (1a-d) with benzaldehyde and pivalaldehyde have been determined and follow the order R = H ～ Cl > Ph > Me. These reactions are promoted by catalytic amounts of a chiral phosphoramide; enantioselectivities of the products obtained show a high sensitivity towards variation of the silyl group. The reactions of the dialkyl substituted chlorosilyl enolates CH₂=C(OMe)OSiClR₂ (1e,f) with benzaldehyde are not promoted by HMPA.