The Preparation of Magnetic Nanoparticle Supported Catalysts and Their Application in Organic Synthesis

过去的几十年，纳米科学在材料、医药、生物、催化等领域得到极其广泛的应用。由于在尺寸上的优势，使用纳米材料作为催化剂载体，可以使异相催化剂均相化，从而提高催化剂的活性和选择性。近年来，磁性纳米颗粒由于其容易分离的特点而作为催化剂载体受到广泛关注。鉴于此，本论文着眼于设计合成一系列磁性纳米颗粒负载的催化剂并研究其在一些有机化学反应中的应用，并进一步研究其重复使用情况。 本论文的主要内容包括以下几个部分： 1．制备了一系列磁性纳米颗粒固载的季胺盐和季膦盐，并将其应用到由二氧化碳和环氧化合物制备环状碳酸酯的反应中，详细研究了温度、催化剂用量、压力等条件对反应的影响，并进一步研究了催化剂的分离和重复使用情况。 2. 合成了二（2－吡啶基）－甲醇，通过Click反应将其固载到磁性纳米颗粒表面并与Pd进行配位，并将其应用于Suzuki和Sonogashira交叉偶联反应中，研究了不同溶剂和反应条件对反应的影响，并讨论了该催化体系的重复利用性能。 3. 合成了一系列的树枝状大分子负载的Click型有机催化剂，并将其用于酮对芳香硝基乙烯化合物的不对称Michael加成反应中。分别研究了在水相和无溶剂条件下反应进行的情况，并研究了催化剂的重复使用情况。 4. 制备了一系列磁性纳米颗粒负载的树枝状大分子催化剂，并应用于环己酮对芳香硝基乙烯化合物的不对称Michael加成反应中。研究了树枝状大分子的代数对催化剂活性的影响，并讨论了催化剂的分离和重复使用情况。In the past decades, nanoscience has been widely applied in the field of materials, medicine, biology and catalysis due to the properties of the nanoparticles. Because of the solubility of nanoparticles in organic and aqueous solvents which was bring about by their sizes, the use of nanoparticles as catalyst support can somehow solve the problems of heterogeneous catalysis such as low reactivity, low selectivity. Among the nanosize supports used, the magnetic nanoparticle are promising ones. Besides the common advantages of nanoparticle, what’s more, they are of superparamagnetic and can be easily collected by external magnet. In view of this, we focused on the preparation and further application of magnetic nanoparticle supported catalyst, and the dissertation is consisted of the following four parts: 1. We have prepared magnetic nanoparticle supported quaternary ammonium salts and phosphonium salts, and studied their applications in the synthesis of cyclic carbonates from epoxides and carbon dioxide. We also discussed the reusability of the catalyst. 2. We have prepared magnetic nanoparticle supported dipyridyl-Pd complex via a click chemistry method and studied their applications in Suzuki and Sonogashira cross coupling reactions. Then we explored the reuse of the catalyst in both of the reactions in detail. 3. We have synthesized dendritic organocatalysts and studied their applications in asymmetric Michael addition reactions in water and under solvent free condition. We also investigated the reuse of the catalyst. 4. We have prepared magnetic nanoparticle supported dendritic organocatalysts, and studied their applications in asymmetric Michael addition reactions. We discussed the influence of generation of the dendrimers on the catalytic activity of the catalysts