分子灵活性对结合强度和奇拉 π 表面的自我排序的影响
Marina M Safont-Sempere1, Peter Osswald, Matthias Stolte
1Universität Würzburg, Institut für Organische Chemie and Röntgen Research Center for Complex Material Systems, Am Hubland, 97074 Würzburg, Germany.
Journal of the American Chemical Society
|May 11, 2011
概括
这项研究探讨了二氧化 (PBIs) 的形状灵活性如何影响其性自我排序. 较长的柔性桥增加了结合强度,但降低了这些功能性染料的性识别效率.
科学领域:
- 超分子化学 超分子化学
- 有机材料科学 有机材料科学
- 基拉尔识别 基拉尔识别 基拉尔识别
背景情况:
- 二氧化 (PBIs) 是重要的功能性染料,在有机电子中具有应用.
- 状自我排序对于创建复杂的超分子架构至关重要.
- 了解分子构成和自我组装之间的关系是设计先进材料的关键.
研究的目的:
- 为了研究 π 核的结构灵活性对烯二氧化物 (PBI) 的奇拉性自我排序特性的影响.
- 合成和溶解具有不同长度的橄乙烯糖醇桥梁的奇拉性宏循环PBIs的阿特罗波-反体.
- 阐明在PBI二元化中控制合性自我识别与自我歧视的机制.
主要方法:
- 合成性宏环PBIs与橄乙烯糖醇桥梁.
- 亚特罗波-反体 (P和M反体) 的分辨率.
- 单晶X射线衍射分析.
- 1D和2D (1)HNMR光谱学. 在 1D 和 2D (1)H NMR光谱学.
- 取决于温度和度的紫外线/紫外线吸收和循环二极化 (CD) 光谱.
主要成果:
- 单晶分析证实了PBI宏循环的结构,并揭示了 π 堆叠的二次体中的左侧超分子螺旋性.
- 嵌合体PBIs (4a-c) 主要形成同位体 (PP和MM) 而不是异位体 (PM),表明嵌合体自我识别.
- 通过更长的桥梁单元来增加构造灵活性,提高了对二分化的结合强度.
- 然而,增加的灵活性导致了性自我识别的效率下降.
结论:
- PBI π核心的形状灵活性显著影响了罗性自我排序行为.
- 诱导适合机制解释了较长的桥梁如何在 π-π 堆叠过程中促进 PBI 支架的平面化.
- 这些发现为设计具有针对先进功能材料量身定制的自组装特性的PBI提供了洞察力.
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