六边形花环:使用多类型的特皮里丁连接物进行离散的超分子碎形结构的自组装
Ming Wang1, Chao Wang, Xin-Qi Hao
1Department of Chemistry and Biochemistry, Texas State University , San Marcos, Texas 78666, United States.
Journal of the American Chemical Society
|April 16, 2014
概括
研究人员使用多类型联结体和Zn (II) 离子制造了新的分形超分子六边形花环. 这些结构克服了传统宏观循环自组装的局限性,产生离散的,刚性的碎形架构.
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
- 纳米技术纳米技术
背景情况:
- 常规的宏循环自组装使用ditotic 2,2':6',2′′-terpyridine (tpy) 连接体往往会导致产品的混合.
- 在二极形建筑块中的120°角通常导致缺乏几何控制,阻碍单个离散的宏观循环结构的形成.
研究的目的:
- 设计和自组装具有碎形几何学的新型超分子六角花环.
- 通过采用多类型的连接体来克服传统宏循环自组合的局限性.
- 调查新形成的碎形架构的结构和几何性质.
主要方法:
- 三重型和四重型tpy配体的设计和合成.
- 使用Zn (II) 离子进行超分子结构的自组装.
- 使用核磁共振 (NMR),电喷射电离化质谱法 (ESI-MS),移动波离子移动性质谱法 (TWIM-MS) 和传输电子显微镜 (TEM) 的表征.
主要成果:
- 两个不同的超分子六边形花环,[Zn9LA6]和[Zn12LB6]的成功自组装,使用多类型的tpy配体和Zn(II) 离子.
- 多拓连接体提供了高的几何约束,导致离散的六角结构的形成.
- 由此产生的六边形花环表现出具有自我相似性的折形几何形状,并具有显著的刚性,正如TWIM-MS.所证实的那样.
- 结构的直径为[Zn9LA6]大约5.5nm,为[Zn12LB6]大约5.8nm.
结论:
- 多拓连接体有效地指导离散的,碎形的超分子架构的自我组装.
- 开发出来的六边形花环代表了与从二位子TPY连接体形成的传统宏循环相比的重大进步.
- 这些刚性碎形结构具有纳米技术和材料科学应用的潜力,需要精确的分子架构.
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