High-performance liquid chromatographic separation of enantiomeric 1,2- and 2,3-
O-isopropylidene-
sn-glycerols was performed on two different stationary phases of opposite configurations:
N-(
S)-1-(α-naphthyl)ethylaminocarbonyl-(
S)-
tert-leucine and
N-(
R)-1-(α-naphthyl)ethylaminocarbonyl-(
R)-
tert-leucine. This caused a reversal in the order of enantiomer elution. The isopropylideneglycerols were chromatographed as 3,5-dinitrophenylurethane derivatives. Complete enantiomer resolution, which permitted an accurate estimation of the optical purity of each enantiomer, was easily achieved on both columns (each 25 cm × 4.6 mm i.d.) within 15 min after an injection by an isocratic elution with hexane/dichloromethane/ethanol (40:12:3, by vol) as the mobile phase. The formations of diastereomeric π-π donor-accepter interaction, hydrogen bonding association, and dipole-dipole stacking between the solutes and the chiral stationary phases were considered as contributing factors to enantiomer resolution. Under optimal conditions, the optical purities of several commercially available 1,2-
O-isopropylideneglycerol enantiomers were successfully determined in this study. The new method used in this study demonstrates that chiral phase high-performance liquid chromatography provides effective resolution, identification, and quantitation of synthetic 1,2- and 2,3-
O-isopropylidene-
sn-glycerol enantiomers.
View full abstract