| In order to expand and carry out systematic research on the catalytic system of simple metalloporphyrins as catalysts for alkanes oxidation with air, and to solve the serious drawbacks in the current synthesis of benzaldehyde and benzyl alcohol such as poor quality of products, pollution to the environment and difficulty in controlling the reaction and so on, we first reported the selective liquid-phase air oxidation of toluene to benzaldehyde and benzyl alcohol catalyzed by metalloporphyrins. The results of the research show that this method of synthesizing benzaldehyde and benzyl alcohol is very effective. The catalytic system has many advantages such as controlled reaction and environmentally friendly conditions. Further more, this method can be applied to selective oxidation of many substituted toluenes to synthesize various substituted benzaldehyde and benzyl alcohol.There are six chapters in this paper. The first chaper mainly introducesd the use of benzaldehyde and benzyl alcohol and the current synthetic method of preparing benzaldehyde and benzyl alcohol. We also reviewed the achievements in direct oxidation of toluene toward benzaldehyde and benzyl alcohol. In the same time, we retrospected the achievements and research trend of alkanes oxidation with molecular oxygen catalyzed by metalloporphyrins. Inspired by the joint of the two branches, this catalytic system of selective liquid-phase air oxidation of toluene to benzaldehyde and benzyl alcohol catalyzed by metalloporphyrins was proposed. The significance and the feasibility of this catalytic system were also carefully analyzed.The second chapter is the section of experiment. In this chapter, the methods of various simple metalloporphyrins were introduced. The methods were also improved according to the experience of myself in experiments. The constructures of various metalloporphyrins were proved by MS, 1HNMR, IR and UV-Vis.In the third chapter, we intensively reported the selective oxidation of toluene catalyzed by cobaltporphyrins. Through comparing the results of toluene oxidation catalyzed by CoTPP and Co(OAc)2, we drawed the conclusion that CoTPP is the better catalyst. In the presence of 3.2 10-5M cobalt tetraphenylporphyrin, 60% selectivity to benzaldehyde and benzyl alcohol at 8.9% conversion of toluene and about 25,000 mole turnover numbers of the catalyst at 165 C were obtained. Compared with traditional synthetic methods of benzaldehyde and benzyl alcohol by the hydrolysis of benzyl chloride, the present method is more suitable for large-scale synthesis of benzaldehyde and benzyl alcohol under the environmentally friendly conditions for the conditions of the reaction can be easily accepted and the selectivity tobenzaldehyde and benzyl alcohol is high. In this section, we also analysised the reason for the differences in the activities of various metalloporphyrins.The fourth chepter mainly introduced the influence of various parameters in this process of toluene oxidation catalyzed by CoTPP and analysis the reason of the different influences. We also obtained the maximum conditions of this catalytic system: use of CoTPP as catalyst and 165 C and 3.2 10-5M cobalt(II) tetraphenylporphyrin and 0.8 MPa and 0.04 m3/h air flow. Furthermore, we studied the retention time of air in the reactor and got the equation concerning the retention time. We also calculated the apparent activation energy of this reaction and proved theoretically that CoTPP acted as the role of catalyst in this reaction.In the fifth chapter, we studied the performance of various metalloporphyrins and analysis the reason for the differences in the activities of various metalloporphyrins.In the sixth chapter, we proposed the plausible reaction mechanism of this catalytic system on the basis of previous achievements on alkanes oxidation with molecular oxygen catalyzed by metalloporphyrins and our own research results.In the last, we drew the general conclusion of this paper.
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