Direct Separation of Enantiomer of Ephedrine and Some Analogues by Reversed-Phase Liquid Chromatography Using (+ )-di-n-butyitartrate as the Liquid Stationary Phase

Abstract

A new chromatographic technique for the separation of enantiomers of β-minoalcohols is presented. A chiral complexing agent, (+)-di-n-butyltartrate (DBT), is used as liquid stationary phase, adsorbed on Phenyl Hypersil. The solutes are eluted with phosphate buffer solutions containing hexafluorophosphate as the counter ion. The resolution of the enantiomers is based on a stereoselective complex formation between DBT and the ion pairs. Separation factors of 1.1 to 1.2 are obtained for ephedrine and norephedrine. The influence of sample structure of some analogues on stereoselectivity is demonstrated.