EFFECT OF SUPERFLUOUS REMOTE POLAR FUNCTIONALITY ON CHIRAL RECOGNITION

During the liquid chromatographic separation of enantiomers on chiral stationary phases (CSPs), non-specific adsorption processes diminish the observed enantioselectivity. The role of those polar groups in the analyte which are not specifically required for chiral recognition was investigated. A series of racemic analytes bearing various non-essential polar groups spatially removed from the sites of chiral recognition were synthesized and chromatographically evaluated. Four scenarios for the interaction of these remote polar groups with the CSP were considered and used to rationalize experimental findings. Cases were observed where enantioselectivity decreased. increased or remained the same on incorporation of a remote polar group.