对映体的气相色谱分析Ⅱ．手性芳香二级醇的分离测定

The Enantiomeric Analysis on Gas Chromatography (GC) Ⅱ. The Separation and Quantitation of Chiral Aromatic Alcohols

在手性毛细管柱Ｃｈｉｒａｓｉｌ－Ｌ－Ｖａｌ（玻璃柱）、ＣＹＤＥＸ－β－全甲基化β－环糊精（交联弹性石英柱）上考察了苯乙醇腈、１－苯基－１－乙醇、１－苯基－１－丙醇、１－苯基－２，２－二甲基－１－丙醇、１－（４－氯苯基）－１－乙醇芳香二级醇对映体分离的色谱行为。并测定了一系列不对称合成实际样品中对映体过量值（即ｅ．ｅ．值）。

The enantiomers of a series of chiral aromatic alcohols such as mandelonitrile, l-phenyl-l-ethanol, 1-phenyl-l-propanol, l-phenyl-2,2-dimetihyl-l-propanol and l- (4-chiloro-phenyl)-l-ethanol, were separated on two chiral capillary columns, Chirasil-L-Val(glass,20×0. 25mm) and CYDEX-β, permethylated β-cyclodextrin(fused silica, 25×0. 22mm). All the racemates were separated to or near to base line. The separation factors(α) = 1. 02-1. 07 were obtained and they were enough for GC separation of enantiomers. The R-alcohols were usually eluted prior to S-ones on CYDEX-β column, but opposite on Chirasil-L-Val column because of the difference of the stationary phases and derivative. The CYDEX-β column displayed excellent chiral selectivity to alcohols. On this column the above alcohols were separated directly except mandelonitrile which must be derivatized by using trifluoroacetic anhydride before it was injected to the column : On the other hand Chirasil-L-Val column displayed poor chiral selectivity to alcohols, and we have only succeeded in the separation of mandelonitrile by conversion of the enantiomer into diastereoisomeric derivative with N -trifluoroacetyl-S-(-)-prolyl chloride (TPC). The separations on both columns could be explained by hydrogen bonding interactions between derivative and GC stationary phase. The enantiomer excess values (e. e. value) of some enantiomers from asymmetric synthesis samples were determined, and they were listed and compared with optical purity (o. p. ), the data are in consistent with each other.