作为阳离子受体的刚性宏环三化物:阳离子依赖的结合固基度和1H化学转移变化
Kihang Choi1, Andrew D Hamilton
1Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA.
Journal of the American Chemical Society
|August 21, 2003
概括
研究人员开发了一种新型的循环三胺离子受体,具有大腔,在有机溶剂中与四面体离子结合更强. 它的结合特性受到离子几何学和溶剂极性的影响.
科学领域:
- 超分子化学 超分子化学
- 有机合成 有机合成
- 离子识别 离子识别
背景情况:
- 阳离子受体对于各种化学和生物过程至关重要.
- 设计具有特定结合腔的宏环受体仍然是一个挑战.
- 了解宿主-客人相互作用是开发选择性分子识别系统的关键.
研究的目的:
- 为了合成和表征一种新型的循环三胺作为一个离子受体.
- 研究宏循环对不同离子几何形状的结合亲和性和选择性.
- 探索溶剂极性和阴离子结构对结合固态度和动态的影响.
主要方法:
- 循环三胺宏循环的逐步合成.
- 在有机溶剂中使用各种技术进行阳离子结合研究.
- 核磁共振 (NMR) 光谱检测宿主-客人相互作用和化学转移变化.
- 用非循环和分子内结的类似物进行对照实验.
主要成果:
- 成功合成了一种新型的循环三化物,它具有很大的中央腔.
- 与球体或平面离子相比,宏环对四面体离子具有增强的结合亲和力.
- 结合性固体几何学对于对称离子而言取决于溶剂极性,但对于四面体p-tosylate而言始终是1: 1.
- 核磁共振 (NMR) 数据表明,离子几何学影响了宏循环腔内的质子化学转移.
结论:
- 合成的循环三胺代表了一个有前途的新类离子受体.
- 受体的选择性是由结合的离子和溶剂环境的几何学决定的.
- 键捐赠者的融合阵列对于有效的离子结合至关重要,这是对照研究证实的.
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