【作者】 沈晓冬；

【导师】 卓广澜；

【作者基本信息】 浙江理工大学 ， 有机化学， 2010， 硕士

【摘要】 本论文主要研究了N-羟基邻苯二甲酰亚胺(NHPI)和过渡金属离子催化、分子氧氧化芳烃侧链甲基制备芳香酸的反应,主要分为以下四个部分:第一部分主要研究了Co(Salen)催化氧化取代甲苯制取代苯甲酸的反应。在乙酸溶剂中,以N-羟基邻苯二甲酰亚胺和过渡金属Salen催化剂,分子氧氧化甲苯制备苯甲酸。论文中比较了各种不同催化剂和自由基引发剂的催化性能。结果表明,在乙酸溶剂中,NHPI/Co(Salen)的催化效果最好,甲苯转化率达到95%以上,苯甲酸产率约85%左右。在常压下,反应温度80℃,该催化体系对具有推电子取代基的底物具有较好的催化氧化效果。第二部分主要研究了负载型钴催化剂催化氧化甲苯的反应。在常压下,110℃乙酸溶剂中,以NHPI和Co/Al(OH)x催化分子氧氧化甲苯。研究表明,甲苯转化率为42%,产物选择性达到95%以上。该催化剂难溶于反应液,反应处理简便。第三部分主要研究了非酸性溶剂中N-羟基邻苯二甲酰亚胺(NHPI)和过渡金属离子钴和锰催化取代甲苯的反应。研究表明,在溴代苯溶剂中,对氯甲苯和对甲基叔丁基甲苯的转化率和产率均达到90%以上。在反应液中加入乙酸锰,可有效提高反应的催化效果。底物上取代基的电子效应影响该催化体系的催化效果。推电子基团有利于芳烃甲基的氧化,吸电子基团不利于氧化反应的进行。第四部分主要研究了烟酸的合成工艺。在溴苯和乙酸混合溶剂中,以N-羟基邻苯二甲酰亚胺(NHPI)和乙酸钴为催化剂催化分子氧氧化3-甲基吡啶制备烟酸,并研究了反应条件对烟酸产率的影响。研究表明,氧气压力(2.0 MPa),反应温度160℃下,N-羟基邻苯二甲酰亚胺(NHPI)和乙酸钴催化氧化3-甲基吡啶制烟酸的产率达到81%。更多还原

【Abstract】 The selective oxidations of aryl hydrocarbon to benzoic acid catalyzed byN-hydroxyphthalimide(NHPI)/transition metal ion were studies in this thesis, and thisthesis divider into four parts as follows:The first part is about the oxidation reaction of substituted toluenes catalyzed byNHPI/Co(Salen). The substrates were oxidized by molecular oxygen which catalyzedby NHPI/M(Salen) in acetic acid. The catalytic performances of various catalyticsystems and catalysts had been studied in this part. The results show that the systemof NHPI/Co(Salen) has better performance, meanwhile, the conversion of toluene isabove 95% and the yield of benzoic acid is about 85%. Some substrates withdonating-electron group, catalyzed by this catalytic system, were oxidized easily at80℃under atmospheric pressure.The second part is about the oxidation reaction of toluene catalyzed by supportedcobalt catalyst. Toluene which catalyzed by NHPI and Co/Al(OH)x-150 is oxidized bymolecular oxygen at 110℃under atmospheric pressure in acetic acid. The resultsshow that the reaction catalyzed by this no soluble catalyst has higher selectivity andthe conversion of toluene is about 42%.The third part is about the oxidation of substituted toluenes which catalyzedNHPI/Co/Mn is carried out in nonacid solvents. The study shows that the conversionsand yields of p-chlorotoluene and p-methyl-(t)-butylbenzene are more than 90%. Thecatalytic performance of cobalt acetate for the oxidation of substitute toluenes ispromoted by added manganese acetate. The substrate with donating-electron group iseasily converted to benzoic acid. However, the substrate with withdrawing-electrongroup is oxidized difficultly. The fourth part is about the synthetic technology of nicotinic acid. The oxidation of 3-methylpyridine to nicotinic acid catalyzed by NHPI/Co(OAc)2 in mixed solvent of acetic acid and bromobenzene has good yield. The optimized reaction condition: NHPI (10 mol%), cobalt acetate (1.5mol%), 3-methylpyridine(4 mmol), 160℃and oxygen(2.0MPa). The yield of nicotinic acid is about 81% under this optimized condition.更多还原