title: The CGC enantiomer separation of 2-arylcarboxylic acid esters by using β-cyclodextrin derivatives as chiral stationary phases.
abstract: Chiral 2-arylcarboxylic acid esters are important intermediates in preparation of enantioenriched 2-arylpropionic acids type Non-steroidal anti-inflammatory drugs (NSAIDs). Enantiomer separation of 2-arylcarboxylic acid esters is crucial for evaluation of the asymmetric synthesis efficiency and the enantiomer excess of chiral 2-arylcarboxylic acid derivatives. The capillary gas chromatography (CGC) enantiomer separation of 17 pairs of 2-arylcarboxylic acid esters enantiomers was conducted by using seven different β-cyclodextrin derivatives (CDs) as chiral stationary phases. It was found that for the 7 pairs of 2-phenylpropionates enantiomers, CDs with both alkyl and acyl substituents especially 2,6-di-O-pentyl-3-O-butyryl-β-cyclodextrin exhibited better enantiomer separation abilities than the other CDs examined. For the 7 pairs of 2-(4-substituted phenyl)propionates enantiomers, 2,3,6-tri-O-methyl-β-cyclodextrin possessed better enantiomer separation abilities than the other CDs. Among the 3 pairs of 2-phenylbutyrates enantiomers examined, only methyl 2-phenylbutyrate enantiomers could be separated by three CDs among the 7 CDs tested, while enantiomers of ethyl 2-phenylbutyrate and isopropyl 2-phenylbutyrate couldn't be separated by any of the 7 CDs tested. Besides the structures of CDs, the structures of 2-arylcarboxylic acid esters including different ester moieties, substituents of phenyl, and different carboxylic acids moieties in 2-arylcarboxylic acid esters also affected the enantiomer separation results greatly. The CGC enantiomer separation results of 2-arylcarboxylic acid esters on different CDs are useful for solving the enantiomer separation problem of 2-arylcarboxylic acid esters.
authors.affiliation: College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China. Electronic address: shixueyan@cau.edu.cn.
authors.forename: Xueyan
authors.initials: X
authors.lastname: Shi
authors.affiliation: College of Science, China Agricultural University, Beijing 100193, China. Electronic address: s12080929@cau.edu.cn.
authors.forename: Feipeng
authors.initials: F
authors.lastname: Liu
authors.affiliation: College of Science, China Agricultural University, Beijing 100193, China. Electronic address: jymao88@gmail.com.
authors.forename: Jianyou
authors.initials: J
authors.lastname: Mao
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry / Q000302:isolation & purification*; D002849:Chromatography, Gas / Q000295:instrumentation*; D004952:Esters; D013237:Stereoisomerism; D047392:beta-Cyclodextrins / Q000737:chemistry*
chemical_list: D002264:Carboxylic Acids; D004952:Esters; D047392:beta-Cyclodextrins; C031215:betadex
keywords: 2-Arylcarboxylic acid esters; Capillary gas chromatography; Chiral stationary phases; Enantiomer separation; β-Cyclodextrin derivatives