Syntheses of (±)-[14CO2H] jasmonic acid and its pure enantiomers

Abstract

(±)‐Jasmonic acid (JA) was converted in 67% yield to the next lower bromomethyl derivative 2 by bromodecarboxylation following Barton's procedure. Protection of the 3‐keto group by ketalization (ethanediol), condensation with K14CN (DMSO) and deprotection gave the [14CN] nitrile 6. The diasteroisomeric semioxamazone derivatives 8a, 8b were resolved by flash chromatography. The hydrolysis of the nitriles 6a, 6b successively by NaOH, then 3N HCl gave (+)‐[14CO2H] JA and (−)‐[14CO2H] JA of high enantiomeric purity (ee≥98%). © 1998 John Wiley & Sons, Ltd.