Heterocycles. XV. Enantioselective Synthesis of Chiral Flavanonols and Flavan-3, 4-diols

Abstract

Chiral flavanonols and flavan-3, 4-diols have been enantioselectively synthesized from the chiral epoxychalcones (-)-2a and (+)-2b. which are obtained by the asymmetric epoxidation of the chalcone 1 under phase-transfer conditions. The absolute configurations of all the compounds obtained are deduced on the basis of the results obtained by circular dichroic spectroscopy on the dibenzoates (-)-5a, (+)-5b, (+)-8a and (-)-8b.