【作者】 蔡敏敏；

【导师】 吕春绪； 魏运洋；

【作者基本信息】 南京理工大学 ， 应用化学， 2002， 博士

【摘要】 空气／氧气作为清洁、价廉的氧化剂越来越受到研究者的重视。论文研究了空气／氧气液相控制氧化对氯甲苯、邻硝基甲苯制取相应的芳香醛。实验表明，在较优的工艺条件下，常压空气氧化、氧气氧化及加压氧气氧化对氯甲苯，对氯苯甲醛的得率分别可达20％、28％。34％，而在高浓度催化剂Co存在下，收率还可提高4～5个百分点。论文着重讨论了碱性条件下，氧气氧化邻硝基甲苯的反应，得出了温度、时间、底物浓度、氧气流量等一般工艺参数对反应的影响，得出在较佳条件下，邻硝基苯甲醛的收率可达30％左右。研究还发现，强碱对反应有一定的助催化作用，这种作用主要是它能协助底物脱氢而造成的。另外，反应还强烈地受到溶剂的影响，实验表明反应在小分子醚胺中进行时，反应的转化率和收率都有明显的提高。在仔细考察了工艺参数的基础上，建立了首步一级，第二步二分之一级的连串反应动力学模型，求出了速率常数K₁、K₂及不同溶剂下的反应活化能Ea，解释了反应的溶剂效应。以EPR研究了反应的机理，得出了碱性条件下不同溶剂中的EPR谱图，并对在2—甲氧基乙胺溶剂中反应得到的EPR谱图进行了详细的解析，进一步说明了反应的溶剂效应，并得出反应首先脱氢，而后是自由基反应历程的结论。更多还原

【Abstract】 As a clean and relatively cheap oxidant, dioxygen/air receives more and more interest. In this dissertation, it is discussed that the preparation of aromatic aldehyde via liquid autoxidation of mono-substituted toluene. It is showed that under optimum condition, the yield of p-chlorobenzaldehyde is 20% of 28% via air or dioxygen oxidation under ordinary pressure, 34% under 0.3Mpa via dioxygen oxidation. If high concentration of Co catalyst is applied, the yield can be further enhanced 4-5 percentage. It is focused on the discussion of process parameter such as temperature, reaction period, and substrate concentration in autoxidation of o-nitrotoluene in alkali system, and the yield of o-nitrobenzalhyde is 30% under optimum condition. It is also showed that the strong base has some co-catalysis effect on reaction and the yield is also remarkably affected by solvent. The small molecule amine with ether bond is the best solvent for preparation. The consecutive reaction kinetics model is set up and the rate k, k, is also calculated out. The reaction mechanism is studied via KPR. and it is substantially concluded that the reaction first undergoes the abstract of hydrogen and then complies radical mechanism.更多还原