【作者】 朱英红；

【导师】 郑小明； 楼辉；

【作者基本信息】 浙江大学 ， 有机催化， 2003， 博士

【摘要】 相转移催化技术(phase-transfer catalysis)是在20世纪70年代初发展起来的有机合成新技术，己被广泛地应用于聚合物、医药、农药、精细化学品等的合成。相转移催化具有许多优点，如反应条件温和，可提高反应速率和产率等。相转移催化剂固载化可以解决产物分离困难、催化剂重复使用等问题，是当前研究的热点之一。本论文对传统相转移催化氟化和固一固一液三相相转移催化酯化反应进行了系统的研究。 第一部分研究内容： 含氟芳香族化合物是农药、医药等的重要中间体，其特殊的应用价值和潜在的经济价值，引起了许多研究工作者和化工生产厂家的注意。通过卤离子交换法制备含氟芳香族化合物是目前颇受重视的方法，但反应需在较高的温度下进行。由于4-二烷基氨基吡啶中供电子的二烷基与吡啶环共振，使正电荷分散于多个原子中，稳定性比吡啶增加。论文系统研究了具有高热稳定性和催化活性的吡啶翁盐系列新型相转移催化剂。 成功地合成了4-二甲氨基吡啶环中N-烷基分别为正丁基、(2-乙基)己基、三苯甲基、苄基、正十二烷基的吡啶翁盐系列相转移催化剂。通过~1HNMR、mp、IR、MS对催化剂进行了结构鉴定。差热分析表明该系列催化剂具有较好的耐高温性能。 研究了该系列催化剂在芳香氯化物与KF的卤离子交换氟化反应中的催化活性，表明其具有良好的反应活性和热稳定性。通过系统地考察KF的用量、催化剂中N-烷基的结构、催化剂中阴离子的结构、反应溶剂、反应温度、芳香氯化物的不同取代基等对催化剂活性的影响等，筛选出催化活性最好的催化剂为4-二甲氨基-N-(2-乙基)己基吡啶鎓盐。在该催化剂作用下，只需反应1.5小时，对氯硝基苯氟化为对氟硝基苯的得率即可高达98.6％。 第二部分研究内容： 乙酸苄酯是一种重要的香精配料，具有新鲜果香的茉莉型香气，应用非常广更多还原

【Abstract】 Catalysis is a useful technology in organic synthesis. Phase-transfer catalyst (PTC) has the considerable advantages, such as permitting reaction carry out under moderate condition, improving reaction rates and yields. In order to dissolve shortcomings existing in homogeneous, immobilization of PTC is one of the current interest to chemist. In this dissertation, traditional phase-transfer fluorination and solid-solid-liquid triphase-transfer esterification were studied, respectively.The first section:Fluorine-containing aromatic compounds are of current interest because of their special chemical and biological properties in agricultural and pharmaceutical research areas. Although a number of methods for the introducing fluorine into the organic molecules have been developed and successfully utilized for synthesis of fluoro aromatic compounds, halogen-exchange by potassium fluoride (KF) seems to be one of the most practical and useful methods. This kind of reaction must be carried out under elevated temperature.4-(N’, N’-dialkylamino) pyridinium salts are the new phase-transfer catalysts. They have higher thermal stabilities than normal pyridinum salts because of the resonance of dialkylamino and pyridine ring, which make the positive charge delocalized in multiple atoms. In this paper, a series of thermal stable PTC based on dimethylamino pyridinium salts were synthesized and characterized by ~1HNMR, mp, IR, and MS. The activities of the catalysts were evaluated in the typical aromatic nucleophilic substitution reaction (fluorination) and the excellent results were obtained.The effects of various reaction conditions such as molar ratio of KF, structure of N-alkyl and anions, the type of substituents in substrates, reaction solvent, and temperature on the activities of catalysts were investigated in detail. Among the catalysts prepared, 4-(N’, N’-dimethylamino)-N-ethylhexyl pyridinium salt (Cat2) exhibited the highest catalytic activity. It gave p-nitrofluorobenzene in yield up to更多还原