在溶液中控制式自组合的六-四-六enzocoronenes
Jishan Wu1, Andreas Fechtenkötter, Jürgen Gauss
1Max Planck Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany.
Journal of the American Chemical Society
|September 10, 2004
概括
带有不同替代剂的六环六enzocoronenes (HBC) 在溶液中自组装. 立体阻碍控制聚合,通过形成离散的单体或二元体来调整光电子属性.
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
- 有机电子 有机电子
背景情况:
- 六环六enzocoronenes (HBCs) 是以其自我组装特性而闻名的圆盘形分子.
- 控制HBC的聚合对于调整它们的电子和光电子特性至关重要.
研究的目的:
- 合成和研究HBC衍生品与不同外围替代物的自我组装行为.
- 了解固体阻碍如何影响溶液中离散分子物种 (单体/二极体) 的形成.
- 为了将自组装行为与由此产生的光电子特性相关联.
主要方法:
- 有效合成圆盘形六环六enzocoronenes (HBCs) 与十二链或多烯树枝.
- 度和温度依赖的 (1) H NMR光谱学用于研究聚合.
- 非线性最小正方形分析用于自组装的定量评估.
- 量子化学计算以支持结构分析.
- 紫外线吸收和光光谱学用于评估光电子特性.
主要成果:
- 用柔性十二链替代的HBC显示出高聚合倾向.
- 具有刚性树突的HBC表现出抑制的pi-pi相互作用,导致可控制的单体-二元平衡.
- 结构修改,比如去除十二基,导致稳定的二次体.
- 改变树突与核心的近距离会产生非聚合的单体.
- 离散的单体和二体物种表现出不同的紫外线吸收和光谱.
结论:
- 外围替代剂的无菌阻碍有效地编程了溶液中的HBCs的自我组装.
- 控制离散单体或二元物种的形成的能力,允许对光电子特性进行微调.
- 这些发现为设计基于HBC衍生物的功能有机材料提供了一条途径.
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