PREPARATION OF OPTICALLY ACTIVE ALPHA-SILYLCARBONYL COMPOUNDS USING ASYMMETRIC ALKYLATION OF ALPHA-SILYLACETIC ESTERS AND ASYMMETRIC METAL-CARBENE INSERTION INTO THE SI-H BOND

摘要

Substituted alpha-silylacetic esters have been prepared in good yields and with reasonable diastereoselectivities by three different routes. The first two involved alkylation of the parent alpha-silylacetic ester enolates, with the chiral auxiliaries being present either on silicon or on the ester function. The third route involving asymmetric insertion of metal-carbenoids into the Si-H bond was found to afford better diastereoselectivities, using pantolactone as chiral auxiliary. (C) 1997 Elsevier Science Ltd. [References: 52]