在溶液中的大型六米分子囊中对客人封装的歧视:pyrogallol[4]arene与resorcin[4]arene囊
1School of Chemistry, The Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel.
Journal of the American Chemical Society
|December 25, 2003
概括
两个相似的hexameric囊显示不同的客人选择性. 虽然一个只封装中性氨基,另一个则结合中性氨基及其质子盐.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 化学物理 化学物理
背景情况:
- 六米囊是超分子结构,在分子识别和封装中具有潜在的应用.
- 了解控制这些囊中的客人选择性的因素对于设计新的功能材料至关重要.
研究的目的:
- 为了研究两个类似的hexameric囊,2b和3b在粉溶液中的客人选择性.
- 为了确定客体质子对这些系统内的封装的影响.
主要方法:
- 核磁共振 (NMR) 光谱被用来研究囊2b和3b的封装行为.
- 实验涉及不同的客人,包括中性试基胺及其相应的盐,由DCl添加形成.
主要成果:
- 囊2b和3b都在粉中形成六米结构,使用类似的建筑单元.
- 囊3b选择性地只封装未加载的试基胺.
- 囊2b表现出更广泛的选择性,封装了非充电的试基胺和它们的质子盐.
- 客体在现场的质子化导致它们从囊3b中弹出,这种现象在各种基链长度 (四到八个碳) 中观察到.
结论:
- 客人的质子化状态显著影响其在hexameric囊中的封装.
- 囊2b表现出一种独特的能力,可以容纳中性和带电的客人,这表明了差异结合应用的潜力.
- 囊3b对充电客人的选择性凸显了超分子识别中充电相互作用的重要性.
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