HPLC separation of 2-aryloxycarboxylic acid enantiomers on chiral stationary phases
作者:A. A. Tumashov、S. A. Vakarov、L. Sh. Sadretdinova、E. N. Chulakov、G. L. Levit、V. P. Krasnov、V. N. Charushin
DOI:10.1007/s11172-021-3165-8
日期:2021.5
reversed-phase HPLC on popular chiralstationaryphases. The best separation parameters were achieved on the chiralphases with the polysaccharide base Chiralcel OD-H and Chiralpack AD under the normal-phase HPLC conditions. The (S)- and (R)-enantiomers of 2-(1-naphthyloxy)- and 2-(2-iodophenoxy)propionic acids with enantiomeric excess ee >99% were isolated using preparative chiralHPLC.
A New Method for Production of Chiral 2-Aryloxypropanoic Acids Using Effective Kinetic Resolution of Racemic 2-Aryloxycarboxylic Acids
作者:Isamu Shiina、Atsushi Tengeiji、Kenya Nakata、Keisuke Ono
DOI:10.3987/com-12-s(n)79
日期:——
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 (Piv(2)O) as an activating agent, bis(alpha-naphthyl)methanol ((alpha-Np)(2)CHOH) 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.