新型表面聚合联萘胺型手性固定相的制备及评价

采用(R)-(+)-1,1'-联萘2,2'-二胺(DABN)作为手性单体, 以键合在3-氨基硅胶上的4,4'-偶氮-二(4-腈基)戊酸(ACVA)作为引发剂, 通过直接引发表面聚合反应, 制备了一种新型HPLC刷型手性固定相(CSP-a). 采用庚烷-醇-有机调节剂-有机酸为流动相, 在柱温30 ℃和UV 254 nm检测条件下实现了在CSP-a上联萘酚衍生物、3,5-二硝基苯甲酰-氨基酸甲酯和乙酯以及一种反式环氧乙烷衍生物对映体的色谱拆分, 考察了有机调节剂和有机酸对样品在CSP-a上拆分的影响. 结果表明, CSP-a对于π-酸及π-碱类化合物都有明显拆分效果, 三氟醋酸调节作用优于冰醋酸, 流动相中加入CH2Cl2和CHCl3可增强保留, 改善分离度.

Preparation of (R)-(+)-1,1'-Binaphthyl-2,2'-diamine Polymer as a Novel Chiral Stationary Phase by Surface-initiated Polymerization and Chromatographic Evaluation

A novel brush-type chiral stationary phase(CSP-a) for HPLC was prepared by surface-initiated polymerization with (R)-(+)-1,1'-binaphthyl-2,2'-diamine as a chiral monomer and dichloride of 4,4'-azobis-4-cyanopentanoic acid bonded on the surface of silica gel as a radical initiator. The resolutions of the enantiomers of binaphthol derivatives, N-3,5-dinitrobenzoyl-D,L-amino acid methyl esters and isopropyl esters, and a trans-ethylene oxide derivative on CSP-a were carried out using heptane-alcohol-organic modifier-organic acid as the mobile phases under the detection conditions of the column temperature of 30 ℃ and UV wavelength of 254 nm. The effects of organic modifier and organic acid on the resolutions of the analytes on CSP-a were examined. The results show that CSP-a prepared was effective for the resolutions of the enantiomers of π-acid and π-base derivatives. Trifluoroacetic acid was a better organic modifier than acetic acid. Adding CH2Cl2 and CHCl3 to the mobile phase could increase retention and resolution of the samples on CSP-a.