GAS-CHROMATOGRAPHIC ENANTIOSEPARATION AND THERMODYNAMIC PARAMETERS OFBICYCLIC DIKETONES

The analytical separation of the enantiomers of seven bicyclic bridgeh ead diketones of varying ring size and molecular shape has been studie d by gas chromatography on permethylated alpha- and beta-cyclodextrin columns. Factors influencing the enantiomer separation are discussed. Thermodynamic parameters Delta G, Delta H and Delta S were determined from variable temperature measurements in order to investigate the mod e of interaction of enantiomers with the chiral stationary phase. The enantiodifferentiations are accounted for, at least in part, by revers ible inclusion complex formation between guest molecules and the stati onary phase during the chromatographic process.