在水中高电荷的超分子宿主的外部和内部客体结合:解剖截然不同的热力学
Carmelo Sgarlata1, Jeffrey S Mugridge, Michael D Pluth
1Department of Chemistry, University of California, Berkeley and Chemical Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720-1460, USA.
Journal of the American Chemical Society
|January 2, 2010
概括
在超分子组合中研究宿主-客人相互作用,揭示了不同的结合行为. 外部结合是以驱动的,而内部封装是以驱动的,为分子识别提供了洞察力.
科学领域:
- 超分子化学 超分子化学
- 解决方案热力学 解决方案热力学
- 主机和客人的化学反应
背景情况:
- 超分子组件为分子识别提供复杂的框架.
- 了解主机-客户互动对于设计功能性材料至关重要.
- 主机-客户系统中的竞争平衡需要多技术分析.
研究的目的:
- 为了研究与水中的[Ga(4) L(6) ](12-) 超分子组合的基客体的竞争宿主-客体平衡.
- 要区分外部离子联结模式和内部封装结合模式.
- 阐明不同客服绑定事件背后的热力学驱动力.
主要方法:
- 核磁共振 (NMR) 光谱学.核磁共振 (NMR) 光谱学.
- 紫外线可见 (UV-vis) 光谱学.紫外线可见 (UV-vis) 光谱学.
- 异热定位热量计 (ITC). 异热定位热量计.
主要成果:
- 核磁共振,UV-vis和ITC共同提供了主机与客人的相互作用的全面热力学概况.
- 对外部与内部客体相互作用观察到不同的结合热力学.
- 外部结合主要由度驱动,归因于有吸引力的客组装表面相互作用.
- 内部封装主要是由驱动的,由溶解和从宿主腔中释放溶剂引起.
结论:
- 这项研究强调了结合多种技术来剖析复杂解决方案平衡的力量.
- 热力学驱动力的显著差异决定了外部和内部客串的结合.
- 溶解效应在超分子组合中的驱动的封装过程中发挥着关键作用.
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