Development of Materials for Asymmetric Recognition by Chiral Modification of Ordered Mesoporous Materials

以D-丙氨酸和L-丙氨酸的N-咪唑基衍生物(C_&lt；14&gt；-L-丙氨酸和C_&lt；14&gt；-D-丙氨酸)以及D-和L-valine(C_&lt；14&gt；-L-Vala和C_&lt；14&gt；-D-Vala)为原料，成功地合成了具有螺旋结构的中孔SiO_2(模板介孔二氧化硅)。用L异构体和D-异构体合成的螺旋粒子的左右手比分别为75/25和25/75，表明螺旋的主要利手是由表面活性剂的利手性决定的。优化了制备手性介孔二氧化硅的合成条件。手性介孔二氧化硅的宏观形貌和介观结构对合成条件极为敏感。用C_&lt；14&gt；-L-丙氨酸和C_&lt；14&gt；-D-丙氨酸的混合物研究了手性表面活性剂的立体异构体对手性AMS的介观结构和形态的影响。螺旋棒状AMS对三氟乙酰丙氨酸乙酯(CF3CO-Ala-Oet)的不对称分离是有效的。利用天门冬酰胺类化合物合成AMS也进行了研究。

Mesoporous silica AMS (anionic surfactant templated mesoporous silica) with helical particles were successfully synthesized by using the chiral anionic surfactants N-miristoyl derivatives of D- and L-alanines (C_<14>-L-AlaA and C_<14>-D-AlaA), as well as D- and L-valines (C_<14>-L-ValA and C_<14>-D-ValA). The left-/right-handed ratios for the helical particles synthesized with L-isomers and D-isomers proved to be 75/25 and 25/75, respectively, suggesting that the predominant handedness of helices was directed by the handedness of the surfactants. The synthesis conditions for obtaining a chiral mesoporous silica have been optimized. The macroscopic morphology as well as the mesostructure of the chiral mesoporous silica was extremely sensitive to the synthetic conditions. The influence of the stereoisomerism of the chiral surfactant on the mesostructure and morphology of chiral AMS was investigated by using a mixture of C_<14>-L-AlaA and C_<14>-D-AlaA. Helical rod-shaped AMS was found to be effective for asymmetric separation of recemic trifluoroacetylalanine ethyl ester (CF_3CO-Ala-Oet). Synthesis of AMS by using asparagin derivatives has also been investigated.