Approximation function for the direct calculation of rate constants and Gibbs activation energies of enantiomerization of racemic mixtures from chromatographic parameters in dynamic chromatography

J Chromatogr A. 2001 Mar 16;911(2):167-75. doi: 10.1016/s0021-9673(00)01259-0.

Abstract

An approximation function for enantioselective dynamic chromatography of racemic mixtures of interconverting enantiomers has been derived that allows the direct calculation of enantiomerization rate constants (k1 and k(-1)) and Gibbs activation energies of enantiomerization, deltaG++ , from chromatographic parameters, i.e., retention times of the enantiomers A and B ((t(A)R and t(B)R), peak widths at half height (WA and wB) and the relative plateau height (hplateau), without computer simulation. The reaction rate constants of enantiomerization, k(-1), obtained with this approximation function, have been validated by comparison with a simulated dataset of 15,625 chromatograms. The mean, standard deviation and confidence interval show a high correlation between the approximated and simulated rate constants. The average deviation from the Gibbs activation enthalpy of enantiomerization, deltaG++, has been estimated to be as small as about +/- 0.11 RT.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chromatography / methods*
  • Kinetics
  • Stereoisomerism
  • Thermodynamics