| Since 1990s, olefin metathesis has gained considerable attention, this is mainly due to the development of founctional groups compatible ruthenium carbene olefin metathesis catalysts. The preparation of ruthenium carbene catalysts, which are of new, high-efficiency and excellent tolerance to a variety of functional groups, is the key to widespread application of olefin metathesis reaction. Although the homogenous catalysts are air-stable and high-efficiency, they also share some disadvantages such as difficulty to remove ruthenium byproducts from the reaction products and poor recyclablity. So, many research efforts focused on immobilization of the homogenous catalysts on heterogenous support materials to improve the performance of ruthenium carbene catalysts. Room temperature ionic liquids (RTILs) are good soluble to many metal complexes, but insoluble to many common solvents. Immobilization of ruthenium carbene catalysts on RTILs make it easy to separate with the final reaction products. One hot research field of olefin metathesis is to synthesize ion-appended ruthenium carbene catalysts soluble in RTILs. In this thesis, we have synthesized an imidazolium-tagged, and a pyridinium-tagged ligand via a series of reactions. The corresponding ion-tagged ruthenium carbene complexes have also been synthesized by ligand exchange with Grubbs II. The activity of the catalysts has also been studied. On the other hand, we have also prepared an anion-appended ligand. This anion-appended ligand was immobilized on dendritic polymer through ion exchange reaction. The corresponding dendritic polymer supported ruthenium carbene complexes have been prepared by ligand exchange with Grubbs II. Compared with the traditional convalent-binding methods, the immobilization via the electrostatic interactions is simpler, and is more convenient for recycling and reuse both the catalysts and the support materials, and is quite apt for industrial continuous-flow processes. |
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