Simple preparation of optically active N-phenyl-carbamato-lactic acid in high optical purity

摘要

Preparation of optically active N-phenylcarbamato-lactic acid of formula (I) in high optical purity comprises: (a) reacting an optically active ester of formula (II) with aqueous caustic alkali solution in the presence of a hardly water-miscible organic solvent; (b) adjusting the resultant aqueous solution of the alkali salt of (I) to pH 3-6 by adding strong acid; and (c) filtering and drying the solid formed. R = Me, Et, n-Pr or i-Pr.