A new method for production of chiral 2-aryloxypropanoic acids using effective kinetic resolution of racemic 2-aryloxycarboxylic acids

Article abstract of DOI:10.3987/COM-12-S(N)79

We report a novel method for the preparation of 2-aryloxypropanoic acids by kinetic resolution of racemic 2-aryloxypropanoic acids using enantioselective esterification. The usage of pivalic anhydride (Piv₂O) as an activating agent, bis(a-naphthyl)methanol ((α-Np)₂CHOH) as an achiral alcohol, and (+)-benzotetramisole ((+)-BTM) as a chiral acyl-transfer catalyst enables the effective separation of various racemic 2-aryloxypropanoic acids to afford optically active carboxylic acids and the corresponding esters with high enantioselectivities. Furthermore, theoretical calculations of the transition states required to form the chiral esters successfully proved the enantiomer recognition mechanism of the asymmetric esterification.