"德克萨斯大小"的分子盒子:通过自组装构建阳离子诱导的超分子物种的构建块
Han-Yuan Gong1, Brett M Rambo, Vincent M Lynch
1Department of Chemistry and Biochemistry, The University of Texas at Austin, Welch Hall 2.204, 105 East 24th Street, Stop A5300, Austin, Texas 78712-1224, USA. hyg2070@iccas.ac.cn
Journal of the American Chemical Society
|March 22, 2013
概括
新的灵活的四胺宏循环结合离子,稳定自我组装的结构. 桥梁组显著影响结合模式和超分子组织,为材料构建提供了新的工具.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 灵活的tetraimidazolium宏循环可以通过阳离子和阴离子识别来稳定超分子结构.
- 在此方面,之前的研究已经确定了cyclo[2](2,6-bis(1H-imidazol-1-yl) pyridine) [2](1,4-dimethylenebenzene) (1(4+)) 的能力.
研究的目的:
- 为了合成和表征新的imidazolium宏循环与修改的中央核心.
- 为了研究这些新的宏循环的离子结合特性和自我组装行为.
- 了解结构修改如何影响超分子组织.
主要方法:
- 新型伊米达宏循环的合成 (2(4+) - 4(4+)).
- 结晶学以确定结构多样性.
- 溶液研究包括1D和2DNMR光谱学 ((1)H, (1)H-(1)H COSY,DOSY,NOESY).
- 电子喷射电离质谱仪 (ESI-MS). 电子喷射电离质谱仪.
主要成果:
- 新的宏循环成功地结合了2,6 - 纳非二甲基酸二离子.
- 所有合成的受体都稳定了自我关联的超分子结构.
- 宏观循环中的桥梁组的性质严重改变了结合模式和超分子组合.
- 分离了多个晶体形式,突出显示了宏观循环的形状灵活性.
结论:
- 结构相关的有改性核心的伊米达宏循环扩展了构建复杂自组装材料的工具包.
- 桥梁组是调节由具有多种构造的灵活受体形成的特定超分子结构的关键决定因素.
- 这些发现为可预测的超分子组装的设计原则提供了宝贵的见解.
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