被限制的客人在化自组装囊中翻滚
Steven Harthong1, Béatrice Dubessy, Jérôme Vachon
1Laboratoire de Chimie, École Normale Supérieure de Lyon, CNRS, 46 Allée d'Italie, F-69364 Lyon, France.
Journal of the American Chemical Society
|October 16, 2010
概括
双酸和酸自组装成分子囊,可以捕捉客人. 这些超分子旋转器表现出受限制的客体运动,展示了受控的分子动力学.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 双酸和酸有能力自我组装.
- 分子囊可以通过超分子组装形成.
- 超分子组件可以表现出独特的动态特性.
研究的目的:
- 为了研究二酸和二酸的自我组装成二维分子囊.
- 探索这些囊中的N-甲基和N-甲基皮科林客体的封装.
- 鉴于受限的客体运动,将超分子组件描述为分子旋转器.
主要方法:
- 在酸盐中溶液状态自组装.
- 对于固态结构的确定,进行X射线衍射分析.
- 扩散顺序光谱 (DOSY) 核磁共振 (NMR) 用于溶液研究.
主要成果:
- 二元分子囊是由酸盐中的二酸和酸组成的.
- N-methylpyridinium和N-methylpicolinium的客人已经成功地被监禁.
- X射线衍射证实了囊形成在自由宿主和客体复合体状态.
- DOSY NMR提供了溶液中囊形成的证据.
- 测量了囊内的客人受限旋转,对于较大的皮科利尼姆客人来说,能量障碍更高.
结论:
- 二酸和酸有效地形成稳定的二度分子囊.
- 超分子囊的功能是分子旋转器,客人的运动取决于客人的尺寸.
- 囊形成是独立于客人的存在,由主机与主机的相互作用驱动.
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