| Homogeneous catalysts have uniform and well-defined reactive centers, which lead to high responsible selectivity. They can catalyze a larger variety of reaction types than traditional solid catalysts, but suffer from their inability (or high degree of difficulty) to be recycled. To solve this problem, the most effective method is the heterogenization of homogeneous catalysts.This dissertation includes two parts : (1) the coupling reactions catalyzed by cyclopalladated complexes of tertiary arylamines, and the immobilization of the catalysts ionic liquids. (2) the immobilization of polyamino acids and its application on the asymmetric epoxidation of (E)- a B -unsaturated ketones.1. The importance of biaryl units as components of many kinds of compounds has attracted enormous interest from the chemistry community. Ullmann coupling and Suzuki coupling are the most important and efficient strategies for the construction of symmetrical and unsymmetrical biaryl compounds.We found that cyclopalladated complexes of tertiary arylamines I - IV were efficient catalysts for homocoupling reactions of iodobenzene. Comparing with traditional catalysts such as Pd(OAc)2 and PdCl2, the catalytic activities of I - IV were higher. Using DMA as solvent and NEt3 as base, the yield of biphenyl was up to 94% after 4h at 132C. The investigation indicated that the parameters, such as solvent, base, temperature, and substituted group had effects on coupling reaction. Other solvents (such as toluene, dioxane) and bases (such as K2CO3, NaOAc) lead to reduced activity and lower yields. The reduction product was increased at higher temperature in shorter time. Both electronic and steric effects were observed for the homo coupling of aryl iodides. Electro-withdrawing and ortho substituents gave desired products in low yields.Ionic liquid have been demonstrated to be ideal immobilizing agents for various transition-metal catalyst precursors, and the organic compounds can be easily separated from the ionic solution. We studied the immobilization of cyclopalladatedcomplexes of tertiary arylamines in [Bmin]BF4. It was necessary to elevate temperature to 164C in [Bmin]BF4. And N\ N'-diethylbenzylamine was better than NEt3 as base. Based on the results of experiments, one plausible mechanism for homo coupling of iodobenze in the presence of palladacycle catalyst was proposed. Tertiary amines played two roles in the catalytic cycle. One worked as base, the other facilitated the regeneration of Pd(0). The later effect was the result of the participation of the hydrogen, which binds with B-carbon of tertiary amines.Suzuki cross coupling is a common strategy for the construction of unsymmetrical biaryl compounds. Palladacycles of tertiary arylamines in [Bmim]BF4 catalyzed cross coupling of aryl halides with phenylboronic acid. There were some differences between homo and cross coupling catalyzed by the same catalysts. Cyclopalladated complexes with ferrocenyl were superior to complexes with aryl. When Na2CO3 used as base, no reaction observed, while good yield was achieved with a little water added, and the yield was up to 88%. When NEt3 with water were used, the mixture of homo and cross coupling products was obtained. Both electronic and steric effects were observed for the Suzuki coupling. But electro-donating and ortho substituents gave desired products in low yields. After the reaction, the product and the catalyst could be easily isolated, and the catalytic system reused 2 times without loss in the yield.2. Chiral epoxides produced by alkene epoxidation are extremely useful building blocks for asymmetric synthesis. Among the catalysts for alkene epoxidation, polyamino acids have some advantages, such as no metal, little pollution and poison. However, when the catalyst comes to practical utility, it tends to block the filter devices in the isolation process.At first, we grafted amino group onto silica surfaces via the formation of covalent bonds. Utilizing this functionalized silica with 3-aminopropyl groups as an initiator, N-carboxy...
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