环境敏感的线索,脱线索和离子诱导的伪素的固定
Han-Yuan Gong1, Brett M Rambo, Elizabeth Karnas
1Department of Chemistry & Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712-0165, United States.
Journal of the American Chemical Society
|January 7, 2011
概括
一个灵活的四离子大循环形成了对环境变化有反应的阳离子诱导的伪. 这些结构可以被锁定在有序的金属结合的多中,使用银 (I) 离子.
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:
- 四子宏观循环作为构建复杂的超分子架构的多功能平台.
- 阴离子模板组装是创建响应性分子系统的关键策略.
- 对于先进的应用,对刺激反应材料的开发至关重要.
研究的目的:
- 通过使用一种新型四离子化宏循环,研究离子诱导的伪素的形成.
- 为了探索这些伪托克桑结构的环境响应 (pH,温度).
- 为了证明能够将这些组件锁定到有序的金属结合的多中.
主要方法:
- 综合和表征的四离子宏循环循环[2](2,6-di(1H-imidazol-1-yl) 皮里丁) [2](1,4-二甲基) 六酸 (1(4+) ·4PF(6) ((-)).
- 使用 bis-carboxylate 客体 (4,4 - - 双二酸和 2,6- 纳非二酸) 的伪素的形成和表征.
- 使用NMR光谱 (1D,2D NOESY),质谱 (ESI-MS) 和单晶X射线衍射的结构分析.
主要成果:
- 四离子宏循环作为一个分子盒子,成功地形成离子诱导的伪.
- 伪甲素对pH和温度的变化表现出反应性.
- 添加Ag(I) 离子会形成有序的,金属结合的多甲结构.
结论:
- 研究的四化宏循环是一个高效的宿主,可以形成对刺激有反应的伪.
- 创造与金属结合的多聚素的能力为新型超分子材料提供了途径.
- 这项工作突出了基于宏观循环的系统在设计先进的功能材料方面的潜力.
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