手性共价有机骨架材料CTpPa-1用于HPLC固定相拆分手性化合物

Separation of Chiral Compounds Using Chiral Covalent Organic Frameworks CTpPa-1 as HPLC Stationary Phase

以合成的1,3,5-三甲酰基间苯三酚(Tp)与(+)-二乙酰基-L-酒石酸酐反应形成的手性有机单体CTp作为手性源,与对苯二胺(Pa-1)反应合成了一种二维重叠层状结构的手性共价有机骨架材料(COFs)CTpPa-1,并采用X射线粉末衍射、红外光谱、扫描电镜和氮气吸附等手段对该材料进行表征。将CTpPa-1与C 18硅胶混合用作固定相制成了高效液相色谱(HPLC)手性柱,在不同比例的正己烷-异丙醇为流动相的色谱条件下,考察了手性柱对不同类型手性化合物的拆分能力。结果显示,该手性柱对醇类、酮类、酚类、有机酸类、胺类等18种外消旋化合物表现出较好的拆分能力,有5个手性化合物达到基线分离,7种手性化合物接近基线分离,其中最大分离度达3.65。该手性柱对一些位置异构体(硝基苯酚、溴苯胺、二硝基苯)也具有一定的分离能力。此外,1-(4-氯苯基)乙醇在手性柱上进样50、100、150、200、250次后,其保留时间与峰面积的相对标准偏差(RSD)分别为0.86%和1.1%,表明该手性柱具有较好的重现性和稳定性。

Chiral covalent organic frameworks(COFs)of CTpPa-1 with two-dimensional eclipsed layered sheet structure was synthesized from p-phenylenediamine(Pa-1)and chiral organic monomer CTp obtained by the reaction of 1,3,5-triformyloroglucinol(Tp)and(+)-diacetyl-L-tartaric anhydride.The CTpPa-1 was characterized by powder X-ray diffraction(PXRD),Fourier transform infrared spectroscopy(FT-IR),scanning electron microscopy(SEM)and nitrogen adsorption.The CTpPa-1 were mixed with C18 to use as a stationary phase for fabricating a packed chiral high performance liquid chromatography(HPLC)column.The resolution ability of the chiral column for different chiral compounds were investigated under different ratios of n-hexane-isopropanol as mobile phase.Results showed that the chiral column exhibited a good resolving ability towards 18 racemates,including alcohols,ketones,phenols,organic acids and amines,among which five chiral compounds reached the baseline separation,and seven chiral compounds were close to the baseline separation.The highest resolution(RS)was 3.65.Some positional isomers including nitrophenol,bromoaniline and dinitrobenzene could be separated on the chiral column.Finally,the reproducibility and stability of the chiral column were evaluated.The relative standard deviations(RSD)for retention time and peak area after 50,100,150,200,250 injections of 1-(4-chlorophenyl)ethanol were 0.86%and 1.1%,respectively,indicating that the chiral column had good reproducibility and stability.