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1、河南科技大学 硕士学位论文 芳腈化反应中水溶剂和微波技术的应用 姓名：王伟 申请学位级别：硕士 专业：有机化学 指导教师：任运来 20091201 摘 要 I 论文题目：论文题目： 芳腈化反应中水溶剂和微波技术的应用芳腈化反应中水溶剂和微波技术的应用 专专 业：业： 有机化学有机化学 研研 究究 生：生： 王王 伟伟 指导教师：指导教师： 任运来任运来 副教授副教授 摘 要摘 要 芳腈代表一类重要的化合物，其不仅存在于一系列医药、染料、杀虫剂 和天然产物的结构中，而且是重要的有机合成中间体，可以方便的转化为杂环 化合物等。芳腈合成方法有许多种，包括熟知的 Rosenmund-von Braun
2、 反 应CuCN 与卤代芳烃直接高温反应，该反应条件苛刻因而不适合敏感底物的 腈化反应。之后，采用钯、镍以及铜等过渡金属催化的方法有了较大改进。但 是上述方法的一个共同不足之处就是，必需剧毒无机或有机氰化试剂如碱金属 氰化物、Me3SiCN 和丙酮氰醇等。幸运的是，廉价、无毒的 K4Fe(CN)6做为 氰化试剂的应用成功解决了这一问题。基于 K4Fe(CN)6的应用，研究者们又发 展了许多新的腈化反应方法，如无配体钯催化等。 做为反应溶剂，水无疑是最廉价且大量易得的溶剂，其不易燃、无毒。由 于水溶剂自身的许多特性，如反应速率加速效应、底物的选择性反应、产物分离 的简化、反应体系 pH 值的调节
3、、添加剂的应用、两相反应体系的应用、高温反 应的进行等，因而近些年来，水溶剂中在有机反应中的应用不断得到发展。 1990 年代以来，微波有机合成发展较快。密封容器中利用微波加热，反 应时间显著缩短、产率大为提高，而且与传统合成方法相比，微波反应能够明 显降低副反应的发生从而提高产物的纯度。微波技术不仅应用于有机合成 (MAOS)，而且还在聚合物合成、材料科学、纳米技术和生物化学中得以应 用。 我们的研究以 K4Fe(CN)6为氰化试剂，集中探索水溶剂在卤代芳烃腈化 反应中的应用，特别是微波加热技术在水溶剂中腈化反应的应用： 1.以无毒 K4Fe(CN)6为氰化试剂、铜催化卤代芳烃腈化反应方法得
4、以改 进，即应用水溶剂和无配体催化剂，该方案更经济、更环保；反应无须惰性气 体保护，操作更简便易行。该方案适用于一系列的碘代芳烃和活泼溴代芳烃， 并且催化剂可以重复利用六次而催化活性仅有些微变化。 2. 我们对环境友好的铜催化卤代芳烃腈化反应方法进行了改进创新：微波 加热下，水溶剂中无配体 Cu(OAc)2H2O 催化反应。这一方案能够应用于碘代芳 河南科技大学硕士学位论文 II 烃和活泼溴代芳烃的腈化反应。并且，腈化产物分离后，溶有催化剂的水相回收 继续催化反应，催化剂重复利用六次而催化效果变化不大。 关关 键键 词：词：腈化，卤代芳烃，铜催化，氰化试剂，水溶剂，微波辅助有机合成 论文类型：
5、论文类型：基础研究 摘要 III Subject: The application of water as a solvent and in conjunction with the use of microwave heating as a tool for the cyanation of aryl halides Specialty: Organic Chemstry Name: Wang Wei Supervisor: Ren Yun-lai ABSTRACT Aryl nitriles represent an important class of compounds since t
6、he motif is found in a range of pharmaceuticals, dyes, agrochemi-cals, and naturalproducts. They are also valuable intermediates in organic synthesis and can be easily transformed to a range of heterocycles. A number of synthetic methods for the preparation of aryl nitriles have been developed inclu
7、ding the direct cyanation of aryl halides by copper(I)cyanide, known as Rosenmundvon Braun reaction. The classical Rosenmundvon Braun procedure can require harsh conditions, making it incompatible with sensitive substrates. While modifi cations to this procedure have been made palladium-, copper-, o
8、r nickel-catalyzed aryl cyanation approaches show more promise. A downside with these protocols was that toxic inorganic or organic cyanide sources such as alkali-metal cyanides trimethylsilyl cyanide or acetone cyanohydrin are often required. However, this has been overcome by the discovery that ch
9、eap, non-toxic potassium hexacyanoferrate(II), K4Fe(CN)6 can be used as a cyanide source. Based around this discovery, a number of methodologies have been developed including some procedures using ligand-free palldium sources. If a solvent is to be used for a reaction, water is the cheapest, most ab
10、undant solvent available. It is nonflammable and nontoxic. The application of water as a solvent in organic transformations has been growing in recent years across a wide range of chemical transformations. With its special properties in terms of rate accelerations, and influence on products selectiv
11、ities, or ease of product isolation, and the range of conditions such as inclusion of additives, pH range, use of biphasic systems, and high-temperature conditions that can be utilized, water will continue to play an important role as a solvent in chemical processes. Since the late 1990s the number
12、of publications related to MAOS has increased dramatically(microwave-assisted organic synthesis). In many instances, 河南科技大学硕士学位论文 IV controlled microwave heating under sealed-vessel conditions has been shown to dramatically reduce reaction times, increase product yields, and enhance product purities
13、 by reducing unwanted side reactions compared to conventional synthetic methods. The many advantages of this enabling technology have not only been exploited for organic synthesis(MAOS) and in the context of medicinal chemistry/drug discovery, but also penetrated fields such as polymer synthesis, ma
14、terial sciences, nanotechnology, and biochemical processes. Research in our laboratory has been focused around the application of water as a solvent for the cyanation of aryl halides, particularly in conjunction with the use of microwave heating as a tool for preparative chemistry and K4Fe(CN)6 as a
15、 cyanide source： 1. Cu-catalyzed cyanation of aryl halides with nontoxic K4Fe(CN)6 was improved to be more economical and environmentally friendly by the use of water solvent and ligand-free catalyst. The reactions can be performed without any inert gas protection, which makes them more easy-handlin
16、g. In addition, the suggested methodology is applicable to cyanation of a wide range of aryl iodides and activated aryl bromides, and allows the catalyst to be reused six times with a very slight change in the catalytic activity. 2. A practical and environmentally benign methodology for Cu-catalyzed cyanation of aryl halides was we
