荷莫基拉尔和中世纪的数字是八个节点和所罗门链接
Nandhini Ponnuswamy1, Fabien B L Cougnon, G Dan Pantoş
1University Chemical Laboratory, University of Cambridge , Lensfield Road, CB2 1EW, Cambridge, U.K.
Journal of the American Chemical Society
|May 17, 2014
概括
研究人员使用性构建块在水中创建了一个宏循环的图书馆. 该研究确定了所罗门链接和图形八节,揭示了构建块性和由此产生的拓学之间的联系.
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:
- 基于纳夫他二胺 (NDI) 的构建块对于构建复杂的分子架构具有多样性.
- 在溶液中形成具有拓意义的宏循环,特别是在水中,仍然是一个重大挑战.
- 了解构建块性和自组装结构的拓之间的关系对于理性设计至关重要.
研究的目的:
- 在水中合成和描述一组二硫化物宏循环库,使用基于同体基的NDI构建块.
- 为了识别形成的拓异构体并阐明它们形成的机制.
- 为了研究构建块的点性对由此产生的宏循环拓学的影响.
主要方法:
- 在水溶液中以同体基的纳二胺基构建块的自组装.
- 通过氧化合形成二硫化物宏循环.
- 使用高性能液态染色学 (HPLC) 分离和识别拓异构体.
- 主要异构体的结构分配基于它们的色谱行为和已知的拓特征.
主要成果:
- 形成了一个二硫化物宏循环库,包含各种拓异构体.
- 最丰富的物种是拓上的所罗门链 (60%的HPLC) 和一个拓上无的数字八节 (18%的HPLC).
- 使用构建块的racemic混合物导致近量化形成一个更稳定的meso数字八节.
- 建筑块的点性和主要宏循环产物的拓性性之间观察到相关性.
结论:
- 基于NDI的构建块的奇拉性显著影响了由此产生的宏循环的拓.
- 特定的拓异构体的形成,如所罗门环和图八节点,由起始材料的立体化学控制.
- 这项工作提出了一种新的策略,通过控制构建块的性和刚性来构建复杂的分子拓.
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