Some reactions of 2'-benzyloxychalcone derivatives and preparation of trans-3-Hydroxy-7,4'-dimethoxyflavanone from a chalcone epoxide

Abstract

Treating 2'-(4-methoxybenzyl)-4,4'-dimethoxychalcone epoxide with hydrochloric acid in acetic acid gave trans-3-hydroxy-7,4'-dimethoxyflavanone (18%), the first dihydroflavonol with a 4'-methoxylsubstituent obtained by this route. This observation indicates the possibility that replacing the 2'-(4-methoxybenzyl) protecting group in the chalcone by one with more powerful electron-releasing substituents could lead to an acceptable synthesis of dihydroflavonols.