六米囊形成的动力学和热力学
Masamichi Yamanaka1, Alexander Shivanyuk, Julius Rebek
1The Skaggs Institute for Chemical Biology and Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Journal of the American Chemical Society
|March 5, 2004
概括
树脂烯1b形成了六合体组件,封装了溶液中的四基盐. 封装在热带上受到青,但稳定性和汇率随着电离子的增加而下降.
科学领域:
- 超分子化学 超分子化学
- 主机和客人的化学反应
- 有机化学 有机化学
背景情况:
- 树脂素是以其形成自组装结构的能力而闻名的宏环化合物.
- 这些结构可以封装各种客分子,影响它们的化学环境.
- 了解控制封装稳定性和客体交换的因素对于设计新的分子系统至关重要.
研究的目的:
- 为了研究在四基盐的存在下,素1b的自我组装.
- 为了确定封装过程的固体几何学和热力学.
- 探索阴离子大小对复合物-客体复合物的稳定性和动态的影响.
主要方法:
- 在水和的CDCl中形成六氨基复星烯1b组合.
- 在Resorcinarene腔内封装四基盐 (2(+) Br(-)) 在Resorcinarene腔内.
- 使用光谱方法分析共同封装的溶剂分子 (CHCl ((3)).
- 客体封装和交换的热力学和动力学研究.
主要成果:
- 树脂烯1b形成六合体囊,封装一个四基盐和溶剂分子.
- 封装是一种内热过程,因溶剂释放而受到热的支持.
- 复杂的稳定性和客人交换率随着氨基离子的链长度的增加而下降.
- 较高的客人交换激活障碍表明过渡状态中的构造约束.
结论:
- 树脂烯1b的自我组装为四基盐提供了一个宿主系统.
- 溶剂分子的释放是封装的关键驱动力.
- 分子识别取决于大小,较大的离子表现出较低的交换动态.
- 对于高效的客人交换来说,可能需要完全解离一个resorcinarene子单元.
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