改性环糊精气相色谱手性固定相拆分对映体的选择性及拆分机理的讨论

 A review on gas chromatographic separation of enantiomers with cyclodextrin derivatives is presented.The influences of substituted groups in cyclodextrins on enantioselectivity and recognition mechanisms are summarized and discussed.     

改性环糊精手性固定相性能及对映体拆分研究

比较了合成的４种戊基化环糊精手性固定相对Ｇｒｏｂ试剂的保留性能。对２０种对映体进行拆分并研究了其可能的拆分机理。     

环糊精衍生物气相色谱手性固定相研究进展

评述近年环糊精衍生物气相色谱手性固定相的研究进展,对环糊精衍生物进行分类并总结了近年来其在GC手性分离上的应用,介绍环糊精衍生物的手性分离机制及纯度问题进展,展望环糊精衍生物作GC手性固定相的应用前景。     

环糊精衍生物作为气相色谱固定相的发展及应用

从环糊精及其衍生物作为气相色的分离机理出发介绍了影响这固定相的因素及其分离应用的近期发展,共评述56篇文章。     

一种新型气相色谱手性固定相的制备及应用

合成了一种新的手性固定相,2,6－二－O－三甲基硅烷基－3－O－乙酰其－β－环糊精,以甲基苯基硅油为稀释剂,成功地将其涂渍到弹性石英毛细管柱上,该手性柱具有柱效高,惰性好,热稳定性好等色谱性能,对几类对映体进行了拆分,多数获得令人满意的效果。β     

两种β－环糊精衍生物手性石英毛细管柱拆分对映体

合成了全戊基化（Ⅰ）和部分戊基化三氟乙酰化（Ⅱ）的两种“环糊精手性固定相。将它们分别与ＯＶ－７混合制备出柱效大于４１００塔片／ｍ，热稳定性可达２１０℃的手性石英毛细管住。对映体拆分结果表明，固定相Ⅰ对醇、二醇、胺、γ－内酯等对映体比Ⅰ有更高的选择性。     

两种β－环糊精衍生物手性石英毛细管柱拆分对映体

 合成了全戊基化（Ⅰ）和部分戊基化三氟乙酰化（Ⅱ）的两种“环糊精手性固定相。将它们分别与ＯＶ－７混合制备出柱效大于４１００塔片／ｍ，热稳定性可达２１０℃的手性石英毛细管住。对映体拆分结果表明，固定相Ⅰ对醇、二醇、胺、γ－内酯等对映体比Ⅰ有更高的选择性。     

环糊精接枝聚硅氧烷气相色谱固定相的手性拆分性能

用环糊精接枝聚硅氧烷（二环[2，6－二－O－戊基－3－O－己烯基（－5）]五环[2，6－二－O－戊基－3－O－甲基－β－CD聚硅氧烷]作气相色谱固定相成功地拆分具有两个手性中心的物质－－2，6－二乙酰氧基庚烷；考察了色谱条件对手性拆分的影响。     

环糊精衍生物气相色谱手性毛细管柱的制备与考察

合成了３种新的含长烷基链的β－环糊精衍生物手性固定相。实验表明，随着烷基链长的增加，对手性卤代烃和酯的立体选择性有所提高；以ＯＶ－７为手性固定相的稀释剂对多数手性化合物的拆分效果好于ＯＶ－１７０１。２，６－Ｏ－二辛基－３－Ｏ三氟乙酰－β－环糊精／ＯＶ－７柱应用于不对称合成及催化中对映体的分离与测定和白酒中乳酸乙酯对映体含量的测定。     

几种拟除虫菊酸甲酯对映体的毛细管气相色谱手性拆分

4种酰基化环糊精衍生物（2，6－二－O－戊基－3－O－丁酰基－β－CD、2，6－二－O－戊基－3－O－戊酰基－β－CD、2，6－二－O－戊基－3－O－庚酰基-β－CD和2，6－二－O－戊基－3－O－辛酰基－β－CD）用作毛细管气相色谱固定相，对顺式－和反式－3－（2－甲基丙烯基）－2，2－二甲基环丙烷羧酸甲酯（菊酸甲酯）、顺式－和反式－3－（2，2－二氯乙烯基）－2，2－二甲基环丙烷羰酸甲酯（二氯菊酸甲酯）、2－（4－氯苯基）－3－甲基丁酸甲酯（戊菊酸甲酯）和顺式－3－（2－氯－3，3，3－三氟丙烯基）－2，2－二甲基环丙烷羧酸甲酯（功夫菊酸甲酯）等6种拟除虫菊酸甲酯对映体进行了拆分，结果表明：所合成的4种环糊精衍生物可将顺式－和反式－菊酸甲酯、顺式－和反式－二氯菊酸甲酯、戊菊酸甲酯及顺式－功夫菊酸甲酯等6种菊酸甲酯对映体较好分离。发现不同的环糊精衍生物手性分离能力不同，溶质的结构变化对分离结果也有较大影响。     

环糊精衍生物涂渍毛细管柱的制备及分离性能

以3种环糊精衍生物分别涂覆在毛细管内壁制得气相色谱毛细管柱,以正十二烷为溶质,测得理论塔板数均在2800/m以上,柱效较高。研究了它们对一系列苯系物位置异构体的分离性能,探讨了硝基氯苯、硝基苯胺和苯二胺等化合物在不同柱上的拆分机理。底物分子和固定相之间的弱相互作用(如氢键、偶极相互作用和π-π堆积作用)等直接影响毛细管柱对底物的分离性能。对于苯二胺的位置异构体,在全对氯苯异氰酸酯化β-CD涂覆的毛细管柱(ACD)上的分离因子为1.88,在多叠氮β-CD衍生物涂覆的毛细管柱(NMCD)上的分离因子为1.41,但在单叠氮β-CD衍生物涂覆的毛细管柱(NSCD)上无法分开;对于硝基氯苯,在NMCD柱和ACD柱上的分离因子相近(前者为1.13/1.11;后者为1.08/1.15),在NSCD柱上则无分离趋势;对于硝基苯胺,在NMCD柱上无分离趋势。同时,苯环上不同取代基间电子效应则影响了异构体在气相色谱中出峰顺序。     

Cyclodextrin derivatives for the GC separation of racemic mixtures of volatile compounds. Part VI: The influence of the diluting phase on the enantioselectivity of 2,6-Di-O-methyl-3-O-pentyl-β-cyclodextrin

As a continuation of previous studies on the use of cyclodextrin derivatives (CD) for the separation of volatile compounds by capillary GC, the influence of diluting phases other than OV-1701 or OV-1701-OH has been investigated. 2,6-Di-O-methyl-3-O-pentyl-β-cyclodextrin (2,6-DiMe-3-Pe-β-CD) was taken as the reference CD derivative, because of the large number of volatile racemates it is able to separate; OV-1701 or OV-1701-OH was chosen as the reference diluting phase. The performance of a column coated with a 0.15 μm film of 10 % 2,6-DiMe-3-Pe-β-CD in OV-1701 was compared with that of analogous columns coated with films of the same thickness containing the same percentage of the CD derivative diluted with stationary phases of different polarity, i.e. PS-086, PS-347.5, and OV-225. Resolution values and separation factors of thirty racemates were used to evaluate the effect of different diluting phases on column performance.     

2-苯基-1-环丙烷羧酸酯对映体的毛细管气相色谱分离研究

使用3-位酰基化的4种2,6-二-O-戊基-3-O-酰基化-β-环糊精衍生物和6-位酰基化的3种2,3-二-O-戊基-6-O-酰基化-β-环糊精衍生物作为毛细管气相色谱手性固定相,对4对2-苯基-1-环丙烷羧酸酯对映体(cis-2-PhCpOMe,cis-2-PhCpOEt,trans-2-PhCpOMe,trans-2-PhCpOEt)进行分离研究。结果表明,对所拆分的4对2-苯基-1-环丙烷羧酸酯对映体而言,3-位酰基化的4种2,6-二-O-戊基-3-O-酰基化-β-环糊精衍生物比6-位酰基化的3种2     

Gas Chromatographic Separation of Enantiomers on Cyclodextrin Derivatives

In investigations concerned with the phenomenon of molecular chirality, the use of gas chromatography for the enantiomeric analysis of stable, volatile compounds is a technique of steadily growing importance. ^[1] In the last three years an important breakthrough in gas-chro-matographic separation of enantiomers has been achieved by using alkylated cyclodextrins (α, β, and γ) as chiral stationary phases in high-resolution capillary columns. In academic and commercial practice two different and complementary strategies have been adopted up to now. In the first, alkylated cyclodextrins are diluted with polysiloxanes and coated on glass or fused silica capillary columns. In the second, lipophilic per-n-pentylcyclodextrins and hydrophilic di-n-pentyl- and hydroxyalkylpermethylcyclodextrins are coated directly in the form of liquid phases onto suitably pretreated glass or fused silica surfaces. These techniques permit enantiomer separations not only for polar diols and alcohols, derivatized hydroxycarboxylic acids, amino acids, sugars, and alkyl halides, but also for nonpolar alkenes, cyclic saturated hydrocarbons, and metal π complexes. An important aspect for practical applications is that in many cases the enantiomers can be separated without previous derivatization. Whereas the resolution of racemates of unfunctionalized hydrocarbons is attributed to an enantioselective host–guest inclusion complex, some observations indicate that for polar guest molecules additional enantioselective interactions are also involved. The new chiral stationary phases can be used over a wide range of temperatures (25 to 250°C). The technique described is likely to become widely adopted as a simple, accurate and highly sensitive method for the enantiomeric analysis of chiral compounds that can be vaporized without decomposition. It will also stimulate future research aimed at finding universal cyclodextrin phases and elucidating the mechanisms of enantioselectivity.     

脲衍生物型手性固定相拆分氟西汀对映体

利用脲衍生物型手性色谱柱拆分药物氟西汀，主要优化了正相分离条件，并讨论了异构体的出峰次序；认为固定相中两个手性中心分别与异构体发生氢键及π－π电子授－受作用，且这两种作用力的强度对不同构型的异构体是不同的，流动相组成主要影响异构体的分析时间。     

手性酰胺聚硅氧烷固定相的制备与气相色谱性能

以L-苯丙氨酸,L-缬氨酸为手性源,合成了二种含末端烯基,具有刚性苯基链节的新型手性酰胺单体;并通过硅氢加成方法将其接枝到含氢硅油上,制备了两种新型手性酰胺聚硅氧烷固定相.这一新方法具有简单易行,各步产率较高的优点,所制备的手性固定相具有较好的毛细管柱色谱性能.手性拆分能力和耐温性.