在一个动态的超分子聚合物中测试多数规则原则的极限
Maarten M J Smulders1, Patrick J M Stals, Tristan Mes
1Laboratory of Macromolecular and Organic Chemistry and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
Journal of the American Chemical Society
|December 18, 2009
概括
研究人员研究了化学结构如何影响素-1,3,5-三胺 (BTA) 衍生物的性放大. 单个立体中心足以进行超分子性放大,而能量惩罚会影响放大极限.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 奇拉性研究 奇拉性研究
背景情况:
- 众所周知,-1,3,5-三胺 (BTA) 衍生物可以形成螺旋式超分子聚合物.
- 状放大是自组装系统中的一个关键现象,但其分子决定因素需要进一步研究.
研究的目的:
- 系统地研究化学结构对BTA衍生物中奇拉放大作用的影响.
- 量化分子结构,能量罚款和奇拉放大程度之间的关系.
- 探索在奇拉放大中多数规则原则的局限性.
主要方法:
- 对BTA衍生物进行系统的化学修饰.
- 取决于温度的放大实验.
- 螺旋逆转和不匹配处罚的分析.
- 混合多数规则实验.混合多数规则实验.
主要成果:
- 对所有BTA衍生品观察到一个恒定的螺旋反转惩罚,归因于分子间键.
- 在非对称地替换的BTA衍生物中检测到奇偶对等效应的合放大.
- 不匹配的惩罚直接与立体中心的数量相关,其中一个立体中心足以进行超分子性放大.
- 通过平衡螺旋反转和不匹配处罚来确定增强合放大的最佳条件.
结论:
- 立体中心的数量是决定不匹配处罚的关键因素,因此决定了性放大程度.
- 多数规则原则有效地利用来自单个立体中心的奇拉信息来实现超分子奇拉性.
- 了解和操纵能量处罚对于增强螺旋式超分子聚合物中奇拉放大至关重要.
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