D,L-alpha-aminoxy酸的循环六作为化物离子的选择性受体
1Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China. yangdan@hku.hk
Journal of the American Chemical Society
|October 17, 2002
概括
循环六二结合化物离子,显示化物比化物和化物更受青. 它的形状在化物结合时发生变化,这表明尺寸互补性决定了选择性.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 离子识别 离子识别
背景情况:
- 循环因其结合离子的能力而闻名.
- 瓦利诺米辛是一种循环,可以选择性地结合阳离子.
- 了解合成的阳离子识别是一个新兴的领域.
研究的目的:
- 合成和表征循环六 2.合成和表征循环六 2.
- 研究循环六的离子结合特性 2. 调查循环六的离子结合特性 2.
- 阐明化离子选择性的结构基础.
主要方法:
- 从交替的d-和l-α-氨基酸合成一个循环六.
- 在非极性溶剂中使用光谱技术进行符合性分析.
- 使用定位方法确定化离子的结合亲和度 (Ka).
- 结合式复合体的结构阐明.
主要成果:
- 循环六二在非极性溶剂中采用C3对称的,类似手的形状.
- 该对化物离子具有选择性结合,其选择性顺序为Cl- > F- > Br-.
- 选择性主要是由离子和腔之间的尺寸互补驱动的.
- 化物结合会诱导形状变化,形成一个更平坦的结构,面向内部的NH组.
结论:
- 循环六二是一种新型的化阳离子合成受体.
- 这项研究强调了在合成酸的阳离子识别中大小互补的重要性.
- 合规灵活性在约束事件和选择性中起着关键作用.
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