Synthesis of <i>trans</i>-resveratrol using modified Julia olefination route

Abstract

Bioactive hydroxystilbinoid−<i>trans</i>-resveratrol [(<i>E</i>)-3,5,4ʹ-trihydroxy stilbene, <b>1</b>] has been synthesized by modified Julia olefination method. The reaction between corresponding carbanion of benzothiazol-2-yl sulfone derivative and <i>p</i>-anisaldehyde dimethyl acetal with sodium hydride as a base, affords mainly <i>cis</i>-3,5,4ʹ-trimethoxystilbene <b>10b</b> with minor quantity of <i>trans</i>-isomer. Both the isomers have been separated in pure form and confirmed by their NMR spectral data. Demethylation of <i>cis</i>-3,5,4ʹ-trimethoxystilbene either with AlCl₃/pyridine or AlCl₃/triethylamine results in the formation of <i>trans</i>-resveratrol.