Mofs Derived Metal Oxides Catalyzed C-H Bond Oxidation

Transition metal-catalyzed C–H bond functionalization has the advantages of easily available raw materials,simple process and high atomic economy.The construction of carbon–carbon/heteroatom bonds has become a research focus of organic synthesis though C–H bonds oxidation.According to the requirements of green chemistry,traditional homogeneous catalytic oxidation of C–H bonds have some problems,such as irrecoverable catalysts and harsh reaction conditions.Researchers will have to explore the more environmental-friendly C–H bond oxidation processes.With the development of research,heterogeneous catalysts have been introduced into C–H acvtivation.Metal organic frameworks（MOFs）and its derived materials have attracted more and more attention because of their unique properties,such as large specific surface area,high porosity,easy design and easy post-modification.Therefore,MOFs and its derived materials have become a valuable strategy to improve the catalytic activity of heterogeneous catalysts.Based on these advantages,three MOFs-derived metal oxide materials were designed in this thesis.The catalytic properties of the catalysts for the synthesis of ketones,amides and nitriles were investigated by the activation and oxidation of C–H bond to construct C–O bond and C–N bond.The main research are as follows:（1）Ru O₂-Ce O₂composites were synthesized by pyrolysis of Ru Cl₃supported on Ce-BTC.Using Ru O₂-Ce O₂as a catalyst,benzyl C–H bond was oxidized to carbonyl compounds in water at room temperature.The characterization showed that the catalyst had the good morphology and pore structure.At the same time,the synergistic effect between Ce-Ru and the reaction mechanism was explored.The results show that a free radical process was involved in this transformation.The properties of the catalyst were stable,and the morphology and catalytic performance of the catalyst did not significantly change after being reused for six times.（2）Heterogeneous catalyst（Co-Ni-CM）was synthesized by using Co-BTC as a precursor,which was successfully used to synthesize amides by the coupling reaction of benzaldehyde and DMF.This reaction system had the good compatibility for a variety of substrates containing different functional groups.The characterization results showed that the interaction between Co and Ni was momentous to the high activity of catalyst.The mechanism experiments indicate that this reaction was a free radical process.The properties of the catalyst were stable,and the catalytic activity and morphology did not significantly change after being recycled for seven times.（3）A series of catalysts were synthesized by several Ce-MOFs supported Ru Cl₃.Studies show that BPDC-Ru O₂-Ce O₂was used as a catalyst to catalyze the dehydrogenation of phenylmethylamine to nitrile in water at room temperature under oxygen atmosphere.This catalytic system could be applied for various amines.The structure of catalyst was characterized,and the interaction was explored between Ce and Ru in the catalytic process.