Ding Jie, Welton Thomas, Armstrong Daniel W
Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
Anal Chem. 2004 Nov 15;76(22):6819-22. doi: 10.1021/ac049144c.
Recently, it has been found that room-temperature ionic liquids can be used as stable, unusual selectivity stationary phases. They show "dual nature" properties, in that they separate nonpolar compounds as if they are nonpolar stationary phases and separate polar compounds as if they are polar stationary phases. Extending ionic liquids to the realm of chiral separations can be done in two ways: (1) a chiral selector can be dissolved in an achiral ionic liquid, or (2) the ionic liquid itself can be chiral. There is a single precedent for the first approach, but nothing has been reported for the second approach. In this work, we present the first enantiomeric separations using chiral ionic liquid stationary phases in gas chromatography. Compounds that have been separated using these ionic liquid chiral selectors include alcohols, diols, sulfoxides, epoxides, and acetylated amines. Because of the synthetic nature of these chiral selectors, the configuration of the stereogenic center can be controlled and altered for mechanistic studies and reversing enantiomeric retention.
最近，人们发现室温离子液体可用作稳定、具有异常选择性的固定相。它们表现出“双重性质”，即分离非极性化合物时就好像它们是非极性固定相，而分离极性化合物时又好像它们是极性固定相。将离子液体扩展到手性分离领域有两种方法：（1）将手性选择剂溶解在非手性离子液体中，或者（2）离子液体本身可以是手性的。第一种方法有一个先例，但第二种方法尚无报道。在这项工作中，我们展示了在气相色谱中首次使用手性离子液体固定相进行对映体分离。使用这些离子液体手性选择剂分离的化合物包括醇类、二醇类、亚砜类、环氧化合物和乙酰化胺类。由于这些手性选择剂的合成性质，可以控制和改变立体中心的构型，用于机理研究和反转对映体保留。
