The Study Of Chiral Separation Methods Of Several Chiral Compounds By Chromatography

It is an universal phenomenon that chiral compounds exist in nature. With the development of science and technology, people have had a deep insight into the phenomenon of the enantioseparation. Therefore, it is becoming more and more important to analyze and separate chiral substances in biochemistry, medicinal chemistry, and organic chemistry as well as asymmetric synthesis and catalysis. So far, the chiral separations with chromatographic methods are mainly performed by thin-layer chromatography(TLC), gas chromatography(GC), high performance liquid chromatography(HPLC) and high performance capillary electrophoresis(HPCE), etc. TLC, HPLC and HPCE are the most frequently used methods in separations of chiral substances.Firstly, seven chiral compounds were used as targets for chiral separation by high performance capillary electrophoresis in this thesis. The influence of various factors was systematically investigated. Secondly, three kinds of cellulose tris(benzoate)s were synthesized from microcrystalline cellulose. The cellulose derivatives were used in thin-layer chromatography and were also coated onto silica gel to prepare CSP. The experimental conditions were investigated and optimized and the chiral recognition mechanisms of these CSPs were discussed.The present paper research mainly constitutes the following four parts:The first chapter: In this thesis, the literatures on chiral separation were briefly reviewed. The kinds of chiral stationary phases were introduced, especially Pirkle type CSPs, Cellulose derivatives CSPs, cyclodextrin derivatives(CDs) CSPs and macrocyclic glycopeptide CSPs.The second chapter: In this part, seven chiral molecules were successfully separated and good results were obtained by high performance capillary electrophoresis using HP-β-cyclodextrin as chiral selector when they were injected from cathode. The effects of the pH of the buffer, the concentrations of the CD derivatives, the type of the background electrolyte and the applied voltage on chiral separation were systematically investigated.The third chapter: Three kinds of chiral stationary phases- Cellulose tribenzoyl(CTB), Cellulose tris(p-chlorobenzoate)(CTPCB) and Cellulose tris(o-chlorobenzoate)(CTOCB) were ultrasonically prepared by the reaction of microcrystalline cellulose with benzoyl chloride, p-chlorobenzoyl chloride and o-chlorobenzoyl chloride. They were characterized by ~1HNMR, IR spectrometry and elemental analysis. The chiral stationary phases were mixed with microcrystalline cellulose and used in thin-layer chromatographic for the separation of some chiral compounds. Eight chiral compounds were completely separated after optimization of mobile phases. The chiral recognition mechanism of CSPs were also discussed.The last chapter: Cellulose tris(benzoate)s were synthesized by the reaction of microcrystalline cellulose with benzoyl chloride. A chiral stationary phase was prepared by coating cellulose tris(benzoate)s on the silic. The influence on chiral discrimination of the coated loadings way was performed. The surface topographies of the packing materials have been investigated by the scanning electronmicroscope.At the last, there is a summary about the progresses of the paper.