摘要:不对称脲类化合物因其在农业，石油化工，制药和生物学方面有潜在广泛的应用价值，因此吸引了研究者极大地兴趣。传统的合成不对称脲类化合物的方法中涉及到有毒的原料如:光气、异氰酸酯等的使用，这种方法不仅造成了环境污染，而且极大的增加了生产的成本，使得不对称脲类化合物在工业生产上受到了极大地限制。因此需要有新的方法来绕过这种限制合成不对称脲类化合物，通过研究发现Lossen(洛森)重排反应能激活异羟肟酸的氧发生重排生成异氰酸酯，异氰酸酯可以直接与胺类化合物反应，所以要寻找一种能在温和条件下催化洛森重排反应发生的试剂。TCT(2,4,6-三氯-1,3,5-三嗪)被广泛用于官能团转移,例如：TCT(2,4,6-三氯-1,3,5-三嗪）可以有效催化羧酸的激活，Swern氧化，Friedel-crafts反应，Beckman重排，糖基氯化等。因此研究TCT在有机合成中的应用很有意义。本论文验证了：48305
1.用TCT介导异羟肟酸发生洛森重排生成的异氰酸酯，其与胺类、醇类化合物能生成相应的脲类、氨基甲酸盐类化合物的反应。
2.探究不同胺类、醇类化合物与TCT介导异羟肟酸发生洛森重排生成的异氰酸酯的反应活性。
3.探究胺类、醇类化合物与TCT介导异羟肟酸发生洛森重排生成的异氰酸酯发应的最优工艺条件。
毕业论文关键词: 洛森重排；2,4,6-三氯-1,3,5-三嗪；异羟肟酸；异氰酸酯；不对称脲类化合物
Cyanuric chloride-Mediated Lossen Rearrangement
synthesis of unsymmetrical urea derivatives
Abstract:Unsymmetrical ureas derivatives have attracted significant interest due to their extensive applications in agriculture, petrochemicals, pharmaceuticals, and biology. The synthesis of urea derivatives traditionally requires reagents based on either phosgene and phosgene surrogates. These approachs are particularly competent for symmetrical urea derivatives. However, phosgene and isocyanates are noxious, unstable, and require special care for handling. This method not only caused the plloution of the environment, and greatly increased the cost of production. Make it in the industrial production is limited. There is wide scope for developing novel methods utilizing mild and efficient methodology. The Lossen rearrangement basically involves the conversion of an O-activated hydroxamic acid into the corresponding isocyanate intermediate. Thus,the quest for reagents which activate hydroxamic acids via the formation of activated O-hydroxamate under mild conditions is ongoing. It has been shown that TCT can promote efficiently carboxylic acid activation, Swernoxidation, Friedel-craft acylation, Beckmanrearrangement, or glycosyl chlorination. Thus, in the light of these results, the discovery of new applications for TCT in organic synthesis is of interest. This thesis mainly studies:
1. Synthesis of carbamates and ureas from hydroxamic acid using TCT as a promoter.
2. Explore the reactivity of different amine and alcohol compounds with TCT mediated the Lossen rearrangement.
3. Optimization of reaction conditions for the synthesis of unsymmetrical urea via TCT-promoted Lossen rearrangement.
Keywords:Lossen rearrangement;Cyanuric chloride; Hydroxamic acids;Isocyanates ;Unsymmetrical ureas
目 录
第一章 绪论 1
1.1 不对称脲类化合物的应用概况 1
1.1.1 不对成脲类化合物在农业中的应用 1
1.1.2 不对称脲类化合物在生物医药和其他行业中的应用 2
1.1.3 不对称脲类化合物的合成方法中存在的问题及发展方向 用TCT进行Lossen重排合成不对称脲:http://www.youerw.com/yixue/lunwen_50863.html