甲基化物的快速固定由一个宏环氨基氨基
Jung-Jae Lee1, Keith J Stanger, Bruce C Noll
1Department of Chemistry and Biochemistry and Walther Cancer Research Center, University of Notre Dame, Notre Dame, Indiana 46556, USA.
Journal of the American Chemical Society
|March 24, 2005
概括
宏环胺与甲基化迅速反应,形成四级盐. 这种化速度比非循环氨基快数千倍,这是由于特定的激活复杂机制.
科学领域:
- 有机化学 有机化学
- 化学动力学 化学动力学
背景情况:
- 由于其结构,宏环胺具有独特的反应性.
- 了解反应动力学对于合成化学至关重要.
研究的目的:
- 为了研究一个宏环胺与甲基化的化动力学.
- 阐明反应机制,并将其与非循环类似物进行比较.
主要方法:
- 在25.0°C时测量反应速度的动力学研究.
- 用X射线晶体学来确定反应物和产物的结构.
- 计算分析以支持拟议的机制.
主要成果:
- 反应通过伪第一阶动力学进行,半衰期为2.0分钟.
- 宏循环氨基化比非循环氨基快5万倍.
- 产物是紧密关联的离子对,而不是完全分离的离子.
结论:
- 有关激活预反应复合物的机制是最受欢迎的.
- 宏环结构显著提高了SN2化速率.
- 结构和运动数据支持拟议的离子对形成机制.
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