2,6-二-O-烷基-β-环糊精涂渍手性固定相分离联萘酚类对映异构体

Liquid Chromatographic Resolution of Binaphthol Enantiomers on a Reversed-phase Column Coated with 2,6-di-O-alkyl-β-cyclodextrin

利用自行研制的2,6 二 O 烷基 β 环糊精涂渍手性固定相,反相色谱模式研究联萘酚类对映异构体拆分.采用2,6 二 O 戊基 β 环糊精涂渍SymmetryC8柱,甲醇 水(体积比60∶40)流动相,联萘酚对映体的容量因子分别为9.11和10.92,分离选择性为1.19,分离度为1.55.联萘酚 2′ 甲氧基和联萘酚 3,3′ 二甲酸对映体在2,6 二 O 戊基 β 环糊精涂渍柱上也得到较好的拆分.出峰顺序均为S 构型在前,R 构型在后.β 环糊精疏水空腔对萘环的包络作用和环糊精端口羟基与萘羟基的氢键作用可能是手性拆分机理的主要作用.

2,6-Di-O-alkyl-β-cyclodextrins were dynamically coated on the octadecylsilanized and octadsilanized silica columns through hydrophobic interaction. These coated columns can be used to separate binaphthol enantiomers by reversed-phase high performance liquid chromatography. A baseline separation of racemic 1,1'-bi-2-naphthols on the Symmetry C_8 coated with the 2,6-di-O-pentyl-β-cyclodextrin with methanol-water (60:40, v/v) as mobile phase was obtained. The capacity factors are 9.11 and 10.92, respectively, and separation factor is 1.19. Good separations of enantiomers of 1,1'-binaphthyl-2-hydroxy-2'-methoxy and 1,1'-binaphthyl-2,2'-dihydroxy-3,3'-dicarboxylic acid were also obtained. The first enantiomers eluted are all S-configuration. The chromatographic property of the coated chiral stationary phase and the mechanisms of enantiomeric separation were discussed. The results showed that hydrogen bonding by naphthyl hydroxyl and inclusion complexation by the naphthyl group between 1,1'-binaphthol and β-cyclodextrin may be responsible for the chiral recognition.