title: Synthesis of novel chiral imidazolium stationary phases and their enantioseparation evaluation by high-performance liquid chromatography.
abstract: Two novel chiral stationary phases (CSPs) were prepared by bonding chiral imidazoliums on the surface of silica gel. The chiral imidazoles were derivatized from chiral amines, 1-phenylethylamine and 1-(1-naphthyl)ethylamine. The obtained CSPs were characterized by Fourier Transform Infrared (FT-IR) spectroscopy and elemental analysis (EA), demonstrating the bonding densities of CSP 1 and CSP 2 were 0.43 mmol g-1and 0.40 mmol g-1, respectively. These two CSPs could be used to availably separate 8 pharmaceuticals, 7 mandelic acid/its derivatives, 2 1-phenylethylamine derivatives, 1 1,1'-bi-2-naphthol, and 1 camphorsulfonic acid in high-performance liquid chromatography (HPLC). It is found that CSP 1 could effectively enantioseparate most chiral analytes, especially the acidic components, while CSP 2 could enantiorecognize all chiral analytes, although a number of components did not achieve baseline separation. Additionally, the effects of mobile phase composition, mobile phase pH and salt content, chiral selector structures, and analyte structures on the enantiorecognitions of the two CSPs were investigated. It is found that high acetonitrile content in mobile phases was conducive to enantiorecognition. Mobile phase pH and salt content could alter the retention behaviors of different enantiomers of the same chiral compound, resulting in better enantioresolution. Moreover, both chiral selector structures and substituted groups of analytes played a significant role in the separation of chiral solutes.
authors: College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
authors: Tao
authors: T
authors: Wang
authors: Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China.
authors: Haiyan
authors: H
authors: Yang
authors: College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China. Electronic address: qiuruchen@yahoo.com.
authors: Ruchen
authors: R
authors: Qiu
authors: Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China. Electronic address: huangsh@qibebt.ac.cn.
authors: Shaohua
authors: S
authors: Huang
mesh_terms: D000588:Amines / Q000737:chemistry; D060326:Chemistry Techniques, Synthetic; D002851:Chromatography, High Pressure Liquid; D003365:Costs and Cost Analysis; D006863:Hydrogen-Ion Concentration; D007093:Imidazoles / Q000138:chemical synthesis* / Q000737:chemistry / Q000302:isolation & purification*; D008958:Models, Molecular; D008968:Molecular Conformation; D012822:Silicon Dioxide / Q000737:chemistry; D013237:Stereoisomerism; D014269:Trifluoroacetic Acid / Q000737:chemistry
chemical_list: D000588:Amines; D007093:Imidazoles; D012822:Silicon Dioxide; C029899:imidazole; D014269:Trifluoroacetic Acid
keywords: Chiral imidazolium; Chiral stationary phase; Enantioseparation; High-performance liquid chromatography; Ionic liquid