【作者】 康润华；

【导师】 严兆华；

【作者基本信息】 南昌大学 ， 有机化学， 2010， 硕士

【摘要】 由于吡咯类杂环化合物在有机化学和药物化学领域的重要地位以及吡咯类化合物反应性质的复杂性,为有机化学理论创新和药物合成既带来了机遇,同时也带来了挑战。我们在合成吡咯类潜在药物分子过程中发现的缩醛交换反应及醚化反应是两个新型的有机反应,而且转化产率高,反应条件温和,操作简单易行,具有广泛的适用性,因此必将丰富和拓展有机化学尤其是吡咯化学的知识领域,而且在有机合成化学当中也将发挥一定的作用。本论文系统研究了吡咯-2-甲醛化合物的缩醛交换反应及醚化反应的反应条件、适用范围及反应机理,共包括以下三章：第1章,综述了缩醛(酮)的制备以及在有机合成中的应用。第2章,系统研究了吡咯-2-甲醛缩醛化合物在醇钠的醇溶液中的缩醛交换反应。首先考察了吡咯-2-甲醛缩醛化合物在碱性条件下的缩醛交换反应的反应条件及适用范围,发现吡咯-2-甲醛缩醛化合物的缩醛交换反应与吡咯环上的H紧密相关；其次根据实验结果提出了可能的反应机理。第3章,系统研究了吡咯-2-甲醛化合物在醇溶液中还原成醚的反应。首先探索了不同的吡咯-2-甲醛化合物在对甲苯磺酸催化剂存在下在醇溶液中的反应情况,发现吡咯-2-甲醛化合物在醇溶液中的还原成醚反应可能跟醛与醇反应生成缩醛的反应是一对竞争反应,而竞争的结果依赖于吡咯环上的电子云密度；其次根据实验现象和实验结果提出了可能的反应机理。更多还原

【Abstract】 Pyrrole compound is very important in organic synthesis and medicinal chemistry. Some reactivity of pyrrolic compounds are still unknown to organic chemists, so the investigaion on pyrrole compounds will bring them opportunities to make some achievements in the aspects of theory innovation and drug synthesis. In the course of study on the synthesis of pyrrole compounds with potential bioactivity, we found a new type of transacetalization of pyrrole-2-carbaldehyde with sodium alkoxides and a new type of etherification of pyrrole-2-carbaldehyde with alcohols, which have the advantages of high yield, mild reaction condition, labile work-up, and broad application scope. Therefore, our results will contribute to broadening the knowledge of pyrrole chemistry and also will find some applications in organic synthesis. In this thesis, the optimization of reaction conditions, application scope and mechanism of transacetalization of pyrrole-2-carbaldehyde with sodium alkoxides and etherification of pyrrole-2-carbaldehyde with alcohols will be described. It contains three chapters as below:Chapter 1, the preparation of acetals and their application in organic synthesis were reviewed.Chapter 2, the transacetalization of pyrrole-2-carbaldehyde in alkaline media was described in detail. We firstly optimized the reaction conditions of transacetalization of pyrrole-2-carbaldehyde with sodium alkoxide. Then, we studied its application scope. Finally, we proposed a possible mechanism to interpret the transacetalization. Our results showed that existance of the free hydrogen at nitrogen atom of pyrrole ring was the most important, and a mechanism in relation to azafulvene was proved by our experiments.Chapter 3, a new type of etherification through the reduction of pyrrole-2-carbaldehyde with alcohol was described. We explored the reduction of a few of pyrrole-2-carbaldehyde substrates with alcohol in the presence of para- toluenesulphonic acid as catalyst. Experimental results showed that etherification of pyrrole-2-carbaldehyde with alcohol may compete with acetalization of pyrrole-2-carbaldehyde with alcohol, and the electron density on pyrrole ring will control what product will be finally formed. A possible mechanism was also proposed.更多还原