有折叠的正体烯子单元的扭曲宏循环
Zacharias J Kinney1, C Scott Hartley1
1Department of Chemistry & Biochemistry, Miami University , Oxford, Ohio 45056, United States.
Journal of the American Chemical Society
|March 18, 2017
概括
研究人员将芳香折叠剂组装成扭曲的宏观循环. 这些形状持久的三角结构,宽度高达2纳米,在宏观循环中限制时表现出较慢的形状动态.
科学领域:
- 超分子化学
- 有机化学
- 聚合物科学
背景情况:
- 折叠体是以采用定义的二次结构和表现出功能性质而闻名的寡合体.
- 将折叠体子单元纳入更大的架构对于生物宏分子高阶结构至关重要,但仍未得到充分探索.
- 芳香折叠剂,如o-phenylenes,提供了一个简单的平台来研究自组装到复杂的架构.
研究的目的:
- 研究o-phenylene折叠物的动态共价组合到扭曲的宏环结构中.
- 描述由此产生的宏循环的形状持久性,对称性和形态动态.
- 探索宏观循环限制对折叠子单元行为的影响.
主要方法:
- 使用动态共价胺形成以组装各种杆状链接物 (p-phenylene,tolan,diphenylbutadiyene) 的o-phenylene四基.
- 使用核磁共振 (NMR) 光谱,包括可变温度的NMR,对合成的 [3 + 3] 大循环进行了表征.
- 分析了形状分布,并区分了同体性 (D3对称) 和异体性 (C2对称) 形状.
主要成果:
- 实现了高效的宏循环,形成了形状持久的三角宏循环,内径高达2nm.
- 通过NMR光谱学成功地区分了D3和C2对称的对应体.
- 观察到在宏循环结构中的限制会减缓o-基团的反转动态.
结论:
- 动态共价化学为构建复杂的基于折叠剂的宏循环提供了有效的途径.
- 由此产生的宏循环具有显著的形状持久性和可调整的对称性.
- 宏观循环限制影响折叠子单位的结构动态,为更高层次的结构控制提供了洞察力.
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