在帽子形分子的超分子螺旋组织过程中,通过奇拉式自我排序构建的同人形柱子
Cécile Roche1, Hao-Jan Sun, Margaret E Prendergast
1Roy & Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania , Philadelphia, Pennsylvania 19104-6323, United States.
Journal of the American Chemical Society
|April 25, 2014
概括
螺旋式的 dendronized 循环三乙烯 (CTV) 化合物自组装成螺旋柱. 这项研究揭示了在晶体状态下前所未有的性自我排序,影响复杂的系统功能.
科学领域:
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
背景情况:
- 树化循环三乙烯 (CTV) 冠以其独特的结构性质而闻名.
- 分子自我组装成有序结构对于开发先进材料至关重要.
研究的目的:
- 合成和表征一套带有各种外围基链的树枝化CTV冠状图书馆.
- 为了研究这些CTV衍生物的自组装行为,这些CTV衍生物在恐溶溶剂和散装状态下.
- 阐明形成的超分子结构,并了解性自我排序的机制.
主要方法:
- 合成带有 chiral,racemic 和 achiral 基链的 dendronized CTV 冠状.
- 在溶液和薄膜中使用循环二重化 (CD) 和紫外线光谱学进行表征.
- 通过差分扫描热度计 (DSC) 和纤维X射线衍射分析散体结构的分析.
- 计算机模拟和分子建模.
- 固态核磁共振 (NMR) 光谱学. 固态核磁共振 (NMR) 光谱学.
主要成果:
- CTV衍生品在恐溶溶剂和散装中自组装成螺旋柱.
- 乙纯CTVs形成单手柱,而racemic和achiral化合物也表现出自组装成螺旋结构.
- 在散装状态下,超分子柱形成3D六角晶体相 (Φ(h) ((k)) 或2D柱状六角液晶 (Φ(h)).
- 最高级的晶体阶段由单手柱组成,类似于扭曲的12倍三螺旋.
- 脱化发生在晶体状态中,通过分子构成变化和构成变体的柱间转移.
结论:
- 经过凝结的CTV表现出了显著的自我组装成可调整的状柱子.
- 这项研究证明了前所未有的超分子性自我排序,即使是从racemic和achiral前体.
- 这些发现对设计复杂的功能性材料和系统具有重大意义.
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