A practical synthesis of the PPARα agonist, (R)-K-13675, starting from (S)-2-hydroxybutyrolactone

A practical synthesis of optically pure PPARα agonist, (R)-K-13675, is described. This process is based on the use of (S)-2-hydroxybutyrolactone, which can be transformed into the requisite n-butyl (S)-2-hydroxybutanoate in an efficient manner. A key reaction is the etherification between the phenol and n-butyl (S)-2-trifluoromethanesulfonyloxybutanoate to give the phenyl ether in excellent yield without loss of optical purity.