A Simple, Effective, and Selective Approach to Synthesize Natural Vicinal Diols from α‐Costic Acid

Abstract α‐costic acid, the main component of Dittrichia viscosa collected from Morocco, was converted to its derivative γ‐costic acid, both products were the subject of a transformation to obtain new oxygenated derivatives (vicinal diols). The starting material, α‐costic acid was converted to methyl‐α and γ‐costate. The two esters were transformed to vicinal diols employing two reagents I 2 / t ‐BuOOH and diluated KMnO 4 . The first one was the regioselectivity activation of carbon‐carbon double bond using iodine, creating an iodonium intermediate which react with t ‐BuOOH to give corresponding diol and the second one was the exploitation of KMnO 4 as an effective and environmentally friendly oxidant. These simple and effective oxidants led us to two natural vicinal diols α and γ esters costic with a good yield.