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Asymmetric cyanosilylation of aryl aldehydes has been achieved utilizing catalytic amounts of novel chiral ligands. Chiral ligands of amino alcohols and aminophosphine gave S-configured cyanosilylated products with up to 84% ee. In contrast, C 2 -symmetric ligands resulted in R-configured products with up to 95% ee.

We have established practical protocols to the stereoselective synthesis of syn- and anti-β-amino alcohols via the electrophile-promoted intramolecular amination of trichloroacetimidates derived from allylic and homoallylic alcohols. Stereoselective total synthesis of natural products containing β-amino alcohol functionality has been achieved by means of these methods.

The natural (+)-lasonolide A (1), an anti-tumor agent, has been synthesized via thermodynamic benzylidene formation at the C 2 2 quaternary chiral center, use of a disulfone equivalent for elongation of the C 1 5 -C 1 7 three-carbon chain as well as introduction of the two trans olefins at C 1 5 and C 1 7 , iodocyclization for the upper THP. Michael addition for the bottom THP, and intramolecular Horner-Emmons olefination for the 20-membered macrolactone.

L-Cladinose, a neutral sugar found in erythromycins and azithromycins, has been synthesized efficiently using enantioselective monobenzoylation of 2-propenylglycerol in the presence of the imine-CuCl 2 catalysts to elaborate the stereogenic quaternary center.

A key intermediate hexahydrofuropyran 2 to (-)-dysiherbaine 1 has been synthesized concisely via intramolecular oxymercuration and iodocyclization to install the asymmetric centers at the ring junction and the amino groupin the tetrahydropyran stereoselectively.

A stereocontrolled synthesis of azetidinone 3 as a key intermediate to 1β-methylcarhapenem 2 has been achieved via iodoamidation of trichloroacetimidate prepared from (Z)-olefinic allylic alcohol 6, aziridine ring-openingreaction with cyanide nucleophile and a tandem β-lactam formation.