通过素结合组装的晶体超分子旋转器的动态表征
Luca Catalano1,2, Salvador Pérez-Estrada2, Giancarlo Terraneo1
1Laboratory of Nanostructured Fluorinated Materials (NFMLab), Department of Chemistry, Materials, and Chemical Engineering "Giulio Natta", Politecnico di Milano , via L. Mancinelli 7, 20131 Milano, Italy.
Journal of the American Chemical Society
|November 20, 2015
概括
研究人员开发了一个模块化套件来创建晶体分子转子. 这些旋转器具有超快的旋转,展示了设计具有调节性质的材料的新方法.
科学领域:
- 超分子化学
- 材料科学
- 有机化学
背景情况:
- 分子旋转器对于开发具有可调节动态特性的先进材料至关重要.
- 设计和合成多种分子旋转器结构可能具有挑战性.
- 自组装为构建复杂的分子架构提供了一个有前途的途径.
研究的目的:
- 为准备晶体分子旋转器设计一个模块化分子套件.
- 实现各种结构的简单访问,具有不同的动态性能和物理特性.
- 研究新型自组合分子旋转器的旋转动力学和机制.
主要方法:
- 采用模块化方法,使用二氧化[2.2.2]作为旋转器,并使用五种替代作为定位器.
- 采用素结合用于晶体分子旋转器的自组装.
- 进行了可变温度 (1) H T1 旋转放松测量以研究旋转动力学.
- 对四极回声 (2) H NMR测量进行线形分析以确定旋转轨迹.
主要成果:
- 通过模块化套件和素结合成功合成了晶体分子旋转器.
- 证明了所有合成结构的超快布朗旋转.
- 在2.4-4.9 kcal/mol之间确定激活能量和 (1-9) × 10(12) s(-1的预指数系数.
- 核磁共振数据显示旋转轨迹与3倍或6倍的对称潜力一致.
结论:
- 模块化套件可以直接访问多样化的晶体分子旋转器库.
- 自组装的旋转器具有高效和超快的旋转动力.
- 这项研究为设计精确控制运动的分子机器和材料奠定了基础.
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