新型核壳和空壳聚合物固载脯氨酸衍生仲胺催化剂的制备及其在不对称串联反应中的应用

发布时间：2018-04-01 06:16

  本文选题：J?rgensen　切入点：Hayashi　出处：《西南大学》2016年硕士论文

【摘要】：近年来迅速发展起来的有机小分子催化剂因其具有环境友好且无金属危害等优势,已成为不对称催化领域的研究热点之一。然而,昂贵有机手性催化剂的回收策略及高催化性能的非均相催化体系,特别是多组分非均相催化体系,成为研究者们面对的新挑战。本文基于绿色化学理念,构建核壳和空壳纳米微球形貌负载J?rgensen Hayashi有机催化剂,改善有机催化剂的催化效能,实现催化性能优良的非均相不对称串联反应。本论文以Boc-L-脯氨酸为初始原料,通过甲基化、亲核加成、脱保护和取代等步骤合成脯氨酸衍生的J?rgensen Hayashi催化剂ProTMS,用三类不同制备方法和工艺条件分别制备聚苯乙烯共聚物负载有机手性催化剂Poly(St/ProTMS)、聚苯乙烯纳米共聚物为内核的核壳形貌负载有机催化剂PS@ProTMS CSNs和空壳纳米聚合物负载有机催化剂AM/ProTMS HNs。并用扫描电镜(SEM)、热重分析(TG)、N2吸附-脱附比表面积、透射电镜(TEM)等分析测试手段对三种不同类型的负载有机手性催化剂的组成、结构和形貌等进行了表征。以反式-硝基苯乙烯、丙醛和肉桂醛三组分的不对称串联加成反应为模板,探索了不同反应温度、溶剂、催化剂用量等条件对Michael/Michael/aldol不对称串联催化反应性能的影响,筛选出了Michael/Michael/aldol串联催化反应的最佳反应条件。催化剂AM/ProTMS HNs(4/b)在Michael/Michael/aldol不对称串联催化反应中的催化性能最好,取得与其均相催化反应相当的催化性能。在各类衍生物的不对称串联加成反应,产率为32 60%,dr=80 93/7 20,对映选择性≥99%ee。反应结束后,通过简单的过滤或离心实现催化剂的回收,在催化剂的重复使用过程中,仍能保持原先的立体选择性,但产物的产率逐渐下降。
[Abstract]:In recent years, the rapidly developed organic small molecule catalysts have become one of the research hotspots in the field of asymmetric catalysis because of their advantages of being environmentally friendly and free of metal harm. The recovery strategy of expensive organic chiral catalysts and heterogeneous catalytic systems with high catalytic performance, especially multicomponent heterogeneous catalytic systems, have become a new challenge for researchers. The morphology of core-shell and hollow shell nanospheres loaded with J? Rgensen / Hayashi organic catalyst can improve the catalytic performance of organic catalyst and realize heterogeneous asymmetric series reaction with excellent catalytic performance. In this paper, Boc-L- proline was used as the initial raw material, and nucleophilic addition was carried out by methylation, nucleophilic addition, methylation and nucleophilic addition of Boc-L-proline. Synthesis of proline derived J? Three kinds of preparation methods and process conditions for the preparation of polystyrene copolymer supported organic chiral catalyst, PS@ProTMS CSNs and hollow shell, respectively, with polystyrene nanocopolymers as core, polystyrene nanocopolymers as core, supported organic catalyst PS@ProTMS CSNs and hollow shell, respectively, were prepared by using three kinds of different preparation methods and process conditions. Nano-polymer supported organic catalyst AM/ProTMS HNs was used for thermogravimetric analysis of the specific surface area of adsorption-desorption of N _ 2 by scanning electron microscope (SEM). The composition, structure and morphology of three kinds of supported organic chiral catalysts were characterized by TEM and TEM. The asymmetric series addition reaction of propionic aldehyde and cinnamaldehyde was used as a template. The effects of different reaction temperature, solvent and catalyst dosage on the performance of Michael/Michael/aldol asymmetric series catalytic reaction were investigated. The optimum reaction conditions of Michael/Michael/aldol series catalytic reaction were screened out. The catalyst AM/ProTMS HNsN 4 / b had the best catalytic performance in Michael/Michael/aldol asymmetric series catalytic reaction. In the asymmetric series addition reaction of all kinds of derivatives, the yield is 32 ~ 60 / 80 / 93 / 7 / 20, enantioselectivity 鈮，

本文编号：1694310