| Recently, the study on the heterogenizing homogeneous catalysts has always been an important topic in chemistry. In the thesis, the coordination compounds were heterogerized by the sol-gel method which overcome the difficulties of the homogeneous catalysts in practice due to their properties of difficult to recover and corrosive to facilities. Furthermore, it can also prevent the catalysts from leaking as prepared by adsorption method. The catalysts prepared in this way have high catalytic activity and selectivity. So the sol-gel method is attractive in the preparation of catalysts.The oxidation of alcohols to the corresponding carbonyl compounds plays a critical role in organic synthesis. Traditional methods for performing such transformation generally involve the use of stoichiometric quantities of inorganic oxidants. However, there are some fatal weakness from either the economic or environmental standard in the traditional methods. Therefore, studying the oxidation process of alcohol with O2 as clean oxidant and B-diketone complexes of VII transition metals as catalysts is essential.Here, four Co(II) or Co(lII) diketone metal complexes were prepared first. Then, the catalytic properties of them on the aerobic oxidation of diphenylcarbinol were studied . The factors affecting on the catalytic activity and selectivity, which were reaction temperature, reaction time, the molar ratios of NHPI and catalyst to substrate, and different catalysts were observed by using orthogonal test method. It was found that the lower oxidation state complex of the same metal has the higher catalytic activity. Furthermore, the catalytic activity increases with the electron donation of the ligand of the complexes. The conversion of biphenylcarbinol can go up to 97.6% ,when the reaction was run for 12 hours at 80 C with the molar ratios of 10mol% and 0.9mol% of NHPI and Co(acac)2 to the substrate, respecrively.During the preparation of the catalysts traped in SiO2 by the sol-gel method, the factors affecting the properties of the catalysts were also investigated by orthogonal test method. The factors involve PH, the molar ratio of water to precursor, the type of catalysts, encapsulating temperature and aging time, drying temperature and so on. When the encapsulating conditions were optimized based on the results above, the catalyst with high activity and selectivity, and leaking-proof were obtained. When the catalyst was used on the oxidation process of diphenylcarbinol to diphenyl ketone, the conversion can be 95.7% with a selectivity of 100%. The catalytic activity of the catalyst is almost same as that of the corresponding homogeneous catalyst. Besides this, the catalyst can be run for 7 times with only 0.0027g(8.1%) of losing of Co(acac)2.Furthermore, B-diketone Co complexes can also be encapsulated firmly in Al2O3 and TiO2 matrix by sol-gel method. When the encapsulated catalysts in this way were used to the aerobic oxidation of dihenylcarbinol, high conversions were also shown. However, the activities ofCo(acac)2/Al2O3 and Co(acac)2/TiO2 are lower than that of Co(acac)2/SiO2.On the other hand the Co(acac)2/SiO2 has the highest strength therefore it has the best recyclable property.Finally, the encapsulated P - diketone Co complexes were applied to aerobic oxidation of cyclohexanol, benzyl alcohol and borneol. When Co(acac)2/SiO2 was used in the oxidation of them, the conversion of them are 60.5%, 77.7% and 90.1%, respectively.The catalysts prepared by sol-gel method were characterized by FI-IR, TG-DTA and N2 adsorption measurement. It was found that Co(acac)2 is physically entrapped in the three dimensional network of different matrixes and stabilized by the matrixes. The catalysts are leaking-proof and their catalytic activities are related with the surface of them.
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