自组装囊的客体封装特性通过动态的乙烯结
Naoki Nishimura1, Kenji Yoza, Kenji Kobayashi
1Department of Chemistry, Faculty of Science, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan.
Journal of the American Chemical Society
|December 17, 2009
概括
这项研究详细介绍了一个分子囊 (3a) 的自组装,该囊由和链接分子组成,可选择性地封装客人. 溶剂的选择显著影响封装,-d6比-d更有利于强烈的,由力驱动的结合.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 分子识别分子识别
背景情况:
- 动态共价化学可以构建复杂的分子结构.
- 洞膜是多功能支架,用于创建具有定义空洞的宿主分子.
- Ester 键为自组装提供动态和可逆的链接.
研究的目的:
- 为了合成和表征一种新型的自组装囊 (3a) 使用四基和二基乙烯链接剂.
- 为了研究囊3a的客体封装选择性和结合热力学.
- 阐明客体吸收和释放的机制以及溶剂对封装的影响.
主要方法:
- 囊3a通过动态乙烯结形成的自我组装.
- 用各种芳香分子 (双和炭衍生物) 进行客体封装研究.
- 使用NMR光谱学和X射线晶体学进行结构性表征.
- 热力学和动力学分析 (关联常数,2D EXSY) 来确定结合模式和机制.
主要成果:
- 囊3a成功自组装并选择性地封装具有特定方向的客分子.
- 观察到显著的溶剂效应:封装在C(6) D(6) 中显示的关联常数 (450-48,000倍) 比CDCl(3) 高得多.
- 在C ((6) D ((6) 中,封装是以力驱动的,而在CDCl ((3) 中,它是由力和力驱动的,CDCl ((3) 作为一个竞争的客人.
- 为客人交换提出了一个链接器部分解离机制,并得到了动力和结构数据的支持.
结论:
- 自组装的囊3a表现出对客体封装的高选择性,受客体替代物和溶剂极性的影响.
- 溶剂选择极大地影响结合亲和力和热力学,-d6促进更强的,由力驱动的结合.
- 涉及连接器解离的动态机制促进了客人交换,突出了囊的响应性.
- 这项研究提供了关于分子识别和动态共价组件内的宿主-客化学的见解.
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