CYCLODEXTRIN DERIVATIVES IN GC SEPARATION OF RACEMIC MIXTURES OF VOLATILES .9. THE INFLUENCE OF THE DIFFERENT POLYSILOXANES AS DILUTING PHASE FOR -ACETYL-6-O-T-BUTYLDIMETHYLSILYL-BETA-CYCLODEXTRIN ON THE SEPARATION OF SOME RACEMATES

The results of a series of experiments concerning the GC enantiosepara tion of some racemates on columns coated with -acetyl-6-O-t-butyldimet hylsilyl-beta-cyclodextrin diluted in two different polysiloxanes (PS- 086 and OV-1701) are reported. The investigation is centered on the in fluence of the diluting phase on the separations of the racemates inve stigated [delta-heptalactone, linalyl acetate, and an homologous serie s of cis-2-(2-alkyl-cyclopropyl)-ethanol (alkyl from ethyl to heptyl)] because one of the two polysiloxanes separated them, whereas the othe r did not. Column retention and efficiency characteristics were invest igated as a function of the diluting phase. Retention increase (RI) an d Gibbs-Helmholtz parameter (Delta(R,S)Delta G) were determined for ea ch of the above racemates, analyzed by different mixtures of the CDD s elector with the two diluting phases. (C) 1995 John Wiley & Sons, Inc.