化学结构和超分子有效度之间的关系,用于形成分子内H键
Hongmei Sun1, Christopher A Hunter, Cristina Navarro
1Department of Chemistry, University of Sheffield, Sheffield S3 7HF, U.K.
Journal of the American Chemical Society
|August 23, 2013
概括
有效度 (EM) 量化了超分子相互作用. 这项研究揭示了分子内H键的EM值取决于结构和几何,而不是溶剂或内在强度.
科学领域:
- 超分子化学 超分子化学
- 化学热力学化学热力学
- 有机化学 有机化学
背景情况:
- 有效的度 (EM) 对于诸如宏分子折叠和带结合之类的超分子现象至关重要.
- 之前关于EM与酸盐二和以太受体的H键的研究是不确定的.
- 与H键捐赠者/受体的色氨酸-氨酸复合体为EM量化提供了一个平台.
研究的目的:
- 系统量化各种超分子系统中分子内H键的有效分子度 (EM) 值.
- 阐明超分子结构,H键强度和溶剂对EM的影响.
- 为了解决以前使用氧化物,胺基和H键受体的EM研究中的模两可.
主要方法:
- 在甲和胺连接体之间形成协调复合体,具有不同的H键受体.
- 在240个不同的系统中系统量化EM值.
- 应用化学双突变周期来剖析热力学贡献并确定EM.
主要成果:
- 确定分子内H键的EM值在1-1000mM的范围内.
- 发现溶剂对EM的影响很小,在烯和四乙烯中具有类似的值.
- 电磁波值显示强烈依赖于超分子架构和几何互补性,但不是内在的H键强度.
结论:
- 超分子有效度主要由几何互补性和架构控制.
- 内在的H键强度和溶剂在确定超分子EM中起到较小的作用.
- 这项工作为理解和预测复杂的超分子组合中的EM提供了强大的框架.
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