固态允许的H型超分子聚合物
Rasitha Manha Veedu1, Niklas Niemeyer1,2, Nils Bäumer1
1Universität Münster, Organisch-Chemisches Institut, Corrensstraße 36, 48149, Münster, Germany.
Angewandte Chemie (International ed. in English)
|October 5, 2023
概括
无菌阻断的二甲基 (BODIPY) 染料意外地形成了更稳定的H型超分子聚合物. 这种增强的稳定性源于特定的C-H⋅⋅⋅F-B相互作用,可以克服固态障碍.
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:
- 具有庞大的群体的π结合系统的功能化通常通过防止对面堆叠来抑制自我组装.
- H型 (共面) 堆叠通常是不受欢迎的,因为它可以导致聚合引起的火和降低材料性能.
研究的目的:
- 研究增加固体阻碍对H型超分子聚合物的自我组装和热力学稳定性的影响.
- 探索非共价相互作用在决定功能化染料自组装行为的作用.
主要方法:
- 三种二甲基 (BODIPY) 染料的合成:甲基BODIPY (1),替代的BODIPY (2) 和替代的BODIPY (3).
- 对这些BODY染料在非极性介质中的自我组装行为的比较研究.
- 分析所得到的超分子结构的热力学稳定性.
主要成果:
- 增加BODIPY染料的硬质体积并没有抑制H型自组装;相反,它增强了H型超分子聚合物的热力学稳定性.
- 观察到复杂的自我组装路径与增加的固体需求.
- 增强的稳定性归因于直角排列的芳香替代剂之间的有利的分子间C-H⋅⋅⋅F-B相互作用,从而弥补了固态排斥.
结论:
- 绝缘效应可以意外地促进H型超分子聚合物的热力学稳定性.
- 平衡竞争的非共价相互作用,如固体排斥和特定吸引力 (C-H⋅⋅⋅F-B),对于控制自组装至关重要.
- 这项工作挑战了对 π 结合系统自组装中的硬质障碍的传统理解.
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