在N-Haloimides和Pyridine-N-oxides的复合体中的N-X⋅⋅⋅O-N素键:一个大型数据集研究
Rakesh Puttreddy1, J Mikko Rautiainen1, Shilin Yu1
1University of Jyvaskyla, Department of Chemistry, P.O. BOX 35, 40014, Jyväskylä, Finland.
Angewandte Chemie (International ed. in English)
|June 14, 2023
概括
这项研究研究了胺N-氧化物和N-化合物之间的素结合 (XB). 素键的强度主要由素供体决定.
科学领域:
- 超分子化学 超分子化学
- 晶体学 晶体学是指结晶学.
- 计算化学计算化学
背景情况:
- 素结合 (XB) 是一种显著的非共价相互作用.
- 了解XB相互作用对于设计新型材料和分子组件至关重要.
- 胺N-氧化物 (PyNOs) 和N-化合物是XB相互作用的常见参与者.
研究的目的:
- 为了全面研究N-X···O-N+素结合系统.
- 开发一个预测模型的素键能量.
- 为了对XB交互的计算,解决方案和固态数据进行相关联.
主要方法:
- 使用密度函数理论 (DFT) 进行结构优化和能源计算的in silico研究.
- 开发一个简单的静电模型 (SiElMo) 来预测XB能量.
- 通过固态分析 (晶体结构) 和溶液状态研究 (1H NMR定位) 的实验验证.
主要成果:
- 一个大数据集由132个DFT优化结构,75个晶体结构和168个1HNMR定位生成.
- 开发的SiElMo模型准确地预测XB能量,与高级DFT计算良好相关.
- 观察到in silico/固态数据和溶液数据之间的相关性,这归因于溶液中的PyNO氧的多牙性质.
- XB强度主要由素供体的σ孔控制,供体强度的特定顺序是:N-糖素>N-糖胺>N-甲胺.
结论:
- 这项研究为素结合特性提供了一个独特的,多方面的观点.
- SiElMo模型提供了一个计算高效和准确的方法来预测XB能量.
- 这些发现突出了素捐赠者的σ孔在确定XB强度方面的关键作用,这对超分子化学的合理设计有意义.
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