丙炔醇类和丙二烯醇类化合物对映体的气相色谱拆分

Gas Chromatographic Enantiomeric Separation of Propargylic alcohols and 2,3-Allenic alcohols

使用全甲基-β环糊精柱(Rt-βDexTMcst柱),对5种丙炔醇类和4种丙二烯醇类化合物对映体的气相色谱分离方法进行了研究,结果4种丙炔醇类和4种丙二烯醇类对映体得到分离,分离因子α为1.01～1.04,分离度R一般大于1.5.方法已用于实际不对称合成样品ee值的测定.探讨了对映体在该柱上的拆分机理,认为烷基取代基适当的疏水性和大小是降低非特异性相互作用、形成相对稳定的不对称环糊精包合物,从而成功拆分光学活性异构体的关键.

Enantiomers of 5 propargylic alcohols and 4 2, 3-allenic alcohols were studied for direct separation by chiral gas chromatography (GC) using a permethylated beta-cyclodextrin column (Rt-betaDex(cst)(TM), 30 m x 0.25 mm ID). Eight racemic alcohols (4 propargylic alcohols and 4 2,3-allenic alcohols) were well separated with the separation factors (a) as high as 1.02 similar to 1.04 and resolutions (R) generally over 1.5. The method had been applied to determine the enantiomeric excess (ee) of samples produced by enantioselective synthetic reaction. The chiral recognition mechanism using the column (Rt-betaDex(cst)(TM), 30 m x 0.25 mm ID) was discussed and believed that the reasonable hydrophobicity and the size of substituent of the sample molecules are important to reduce non-special interaction and form relatively stable asymmetric inclusion, which result in enantiomer separation.