水体系下高取代度甲壳素醚的均相合成及手性分离材料

Homogeneous etherification of chitin in water systems is a new method for the chemical modification of chitin, and the unique helical structure of chitin derivatives provides better chiral selectivity, which is important for transformation and use of chitin renewable resource. Therefore, chitin will be directly dissolved in NaOH/ urea aqueous solvent. And then the new solvent is as reaction medium, molecular design of chitin will be performed on the basis of etherification reaction and three-point interaction principle. The chitin ethers will be synthesized in homogeneous conditions. The molecular structure of the target products will be further clarified by NMR, elemental analysis et al. The homogeneous synthesis scientific laws of chitin derivatives will be revealed in new solvent system. And homogeneous synthesis method of chitin ethers will be established in the solvent system.Besides, chitin derivatives will be prepared into chiral separation medium, which will be used to separate chiral compounds. The separation properties of chiral separation medium of chitin will be investigated, and the mechanism of chiral separation will be revealed. The results of this study will contribute to establish the green synthesis technology of chitin derivatives in NaOH/ urea water system, and purification technology of separating chiral natural ingredients, which will provide a theoretical basis and technical support for further development and utilization on chitin resources.

水体系下，甲壳素均相醚化反应是制备高取代度甲壳素醚的新方法。甲壳素醚类衍生物骨架结构上含有大量的手性碳原子，外加上其螺旋链的超分子结构，提供了一种独特的手性环境，这对甲壳素资源的转化与利用意义重大。为此，本项目拟将甲壳素直接溶于NaOH/尿素-水溶液，以该溶剂为反应介质，依据醚化反应原理和手性"三点作用"原理，通过分子设计，选择适当的醚化剂均相合成系列甲壳素醚类衍生物。通过核磁、元素分析等表征手段，明确甲壳素醚类衍生物的结构，并揭示该溶剂体系下甲壳素醚类衍生物的均相合成机制，建立该溶剂体系下高取代度甲壳素醚的均相合成方法。然后以甲壳素醚类衍生物为新型手性分离介质，制备成系列高效液相色谱手性固定相和手性膜材料，研究其对多种外消旋体的选择性分离性能，并揭示手性拆分机理。本研究成果可丰富甲壳素化学及手性分离科学内涵，并为甲壳素资源的合理开发利用提供理论依据和技术支持。

项目围绕甲壳素的醚化改性、甲壳素醚类衍生物的性质、甲壳素醚类衍生物手性分离材料的制备及应用开展了研究。水体系下通过均相醚化反应，成功制备了甲壳素季铵盐、丙烯酰胺改性甲壳素、羧甲基甲壳素等一系列甲壳素醚类衍生物。研究了甲壳素季铵盐的絮凝性能、丙烯酰胺改性甲壳素的流变性能、羧甲基甲壳素的吸湿保湿性能。制备了丙烯酰胺改性甲壳素共混膜，探讨了膜材料的力学性能及抑菌性能。成功制备了甲壳素季铵盐阳离子聚电解质液相色谱手性固定相，并对四氢萘胺外消旋体进行了成功拆分，考察了取代度和分子量等因素的影响规律；制备了丙烯酰胺改性甲壳素阴离子聚电解质手性固定相，以及羧甲基甲壳素、羟乙基甲壳素、羟丙基甲壳素手性固定相。确定了甲壳素季铵盐、丙烯酰胺改性甲壳素、羧甲基甲壳素、羟乙基甲壳素、羟丙基甲壳素的最佳合成条件，建立了具有实际应用前景的甲壳素醚类衍生物的绿色合成工艺；进一步明确5种甲壳素醚类衍生物的结构及理化性质，为新型甲壳素功能材料的制备提供了重要依据；成功研究出了系列甲壳素醚类衍生物液相色谱手性固定相；培养了6名硕士研究生；取得各类学术成果10项，其中发表学术论文8篇（SCI/EI收录2篇，北大中文核心5篇），湖北省优秀学士学位论文1篇，湖北省大学生优秀科研成果三等奖1项；还有3篇学术论文待发表。研究成果进一步丰富了甲壳素化学及手性分离科学内涵，并为甲壳素生物质资源的合理开发利用提供了重要的理论依据和技术支撑。