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以低毒醇为溶剂的氯代反应研究

时间:2018-10-19 14:40来源:毕业论文
从绿色化学的角度出发,以低毒、廉价三氯异氰尿酸(TCCA)为氯代试剂,以4-氨基苯磺酸为催化剂,苯乙酮类化合物为反应底物,低毒的乙醇作为溶剂进行α-氯代反应的研究。希望能减

摘要: 氯代反应是一类重要的有机合成反应,氯代产物是非常有用的合成中间体。然而传统的氯代反应有很多缺点,例如:毒性强、污染大、选择性差。因此,探索一条操作简单、高选择性、低毒的工艺路线是十分必要的。本文从绿色化学的角度出发,以低毒、廉价三氯异氰尿酸(TCCA)为氯代试剂,以4-氨基苯磺酸为催化剂,苯乙酮类化合物为反应底物,低毒的乙醇作为溶剂进行α-氯代反应的研究。希望能减少合成过程中造成的污染,提高反应的选择性和产率。29289
实验表明优化后的条件为:n(苯乙酮):n(TCCA)=3:1,4-氨基苯磺酸1.0 mmol,乙醇5 mL,常温,反应时间20 min,α-一氯代苯乙酮的产率为92.5%。苯乙酮类化合物的α-一氯代物产率在85.5~95.3%;n(苯乙酮):n(TCCA)=3:2,酸用量1.75 mmol,常温,反应30 min,α,α-二氯代苯乙酮的产率为94.2%。苯乙酮类化合物的α,α-二氯代物产率在86.0~95.6%。
毕业论文关键词: 绿色化学;选择性;氯代反应;酸性催化剂
 Study on the chlorinations using alcohol with low toxicity as solvents
Abstract: Chlorinations are important transformations in organic synthesis as the chlorinated products are very useful intermediates. However, traditional methods of chlorination have many disadvantages,such as strong toxicity, serious pollution and poor selectivity. It is necessary to explore a process route with simple operation, high selectivity and low toxicity. From the viewpoint of green chemistry, α-chlorinations are studied in this dissertation. Trichloroisocyanuric acid (TCCA) with low toxicity and low price is used as chlorinated reagent, 4- amino benzene sulfonic acid is used as catalyst acetophenones are used as reaction substrate, ethanol with low toxicity is used as solvent in this study. It is hoped that the pollution caused by the synthesis process can be reduced, and the selectivity and yield of the reaction can be improved.
The experiment showed that the typical procedures were as follows: the ratio of acetophenone to TCCA was 3:1, the catalyst was 1.0 mmol, ethanol was 5 ml, the temperature was room temperature and the reaction time was 20 min, the yield of α-monochloro acetophenone was 92.3%. The yields of α-monchlorided compounds  acetophenones were 85.5~95.3%; the ratio of acetophenone to TCCA was 3:2, the catalyst was 1.75 mmol, the temperature was room temperature, and the reaction time was 30 min, the yield of α,α-dichloro acetophenone was 94.2%. The yields of α,α-di chlorided compounds of acetophenones were 86.0~95.6%.
Key words:  green chemistry; selectivity; chlorination; acid catalyst
 目 录
1 前言.1
1.1 酸性物质催化反应综述1
1.1.1 无机酸性催化剂在有机合成中的应用1
1.1.2 有机酸性催化剂在有机合成中的应用4
1.2 一氯二氯代选择性重要性和难度5
1.2.1 一氯二氯代选择性重要性5
1.2.2 一氯二氯代选择性的难度6
1.2.3 二氯代发生的例子6
1.3 小结7
2 以低毒醇为溶剂的氯代反应研究.9
2.1 一氯代反应条件优化9
2.1.1 结果与讨论9
2.2.2 实验部分12
2.2 一氯代反应普适性研究.13
2.2.1 结果与讨论.13
2.2.2 实验部分.14
2.3 二氯代反应条件优化.16
2.3.1 结果与讨论.17
2.3.2 实验部分.20
2.4 二氯代反应普适性研究.22
2.4.1 结果与讨论.22
2.4.2 实验部分.23
3 结论26
致谢27
参考文献28
 1 前言
1.1酸性物质催化反应综述
在有机反应中,酸性催化剂作为重要因素影响着反应速率和目标产物的收率。不仅在烃类裂解、重整、异构等石油炼制过程中需要用到酸性催化剂,同时在烯烃水合、烯烃聚合、醇酸酯化等石油化工和精细化工过程中它也发挥着不可替代的作用。因此,酸催化剂被认为是这一系列重要工业的基础[1]。下面分为以下两类进行酸性物质催化反应的综述。 以低毒醇为溶剂的氯代反应研究:http://www.youerw.com/huaxue/lunwen_24447.html
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