具有NH···N和CH···N键的AAAA-DDDD四重键阵列
David A Leigh1, Craig C Robertson, Alexandra M Z Slawin
1School of Chemistry, University of Edinburgh, The King's Buildings, West Mains Road, Edinburgh EH9 3JJ, UK. david.leigh@manchester.ac.uk
Journal of the American Chemical Society
|June 15, 2013
概括
这项研究探讨了一种四重键阵列,证明用CH···N相互作用取代NH··N键,保持强大的分子相互作用. 这些阵列可以通过使用酸和进行可逆开启和关闭.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 四重键阵列对于分子识别和自我组装至关重要.
- 了解不同类型的键 (NH···N与CH···N) 的作用,是设计稳定的超分子结构的关键.
研究的目的:
- 为了研究四重键阵列的结构和结合性质.
- 评估CH···N相互作用对阵列整体稳定性的贡献.
- 为了探索这些键图案的可切换性.
主要方法:
- 在X射线测定晶体结构.
- 光谱分析 (暗示K (a) 在溶液中的测量).
- 酸定位实验以证明切换行为.
主要成果:
- 分析了强的NH···N四重键阵列的晶体结构.
- 在复杂 [5·6] 中用CH··N相互作用取代NH···N,只会略有降低结合亲和力,这表明CH···N相互作用的贡献很大.
- 该NH··N/CH··N阵列在添加酸和时证明了可逆切换.
结论:
- CH···N 相互作用可以有效地参与强大的四重键阵列.
- 设计的AAAA-DDDD图案具有可调和可逆的特性,使其适合响应性材料.
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