素的实验定量⋅⋅⋅Arene 范德瓦尔斯 接触器
Andrew M L West1, Nicholas Dominelli-Whiteley1, Ivan V Smolyar1
1EaStCHEM School of Chemistry, University of Edinburgh Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK.
Angewandte Chemie (International ed. in English)
|July 20, 2023
概括
素⋅⋅⋅烯相互作用在溶液中是不利的,由排斥驱动,而不是气相分散. 这些接触在某些溶剂中不太受欢迎,但仍然比甲基⋅⋅⋅相互作用弱.
科学领域:
- 超分子化学 超分子化学
- 物理有机化学 有机化学
背景情况:
- 结晶学和计算研究表明,和素之间存在有利的相互作用.
- 在溶液中进行实验量化是具有挑战性的,因为素的硬质变异.
研究的目的:
- 用实验量化各种溶剂中的⋅⋅⋅相互作用.
- 为了阐明解决方案中这些相互作用背后的驱动力.
主要方法:
- 分子平衡系统的合成.
- 在17种溶剂和混合物中使用1H NMR光谱进行量化.
- 使用分区对称性适应扰动理论 (SAPT0) 能量进行分析.
主要成果:
- 素⋅⋅⋅烯相互作用在溶液中是不利的 (ΔG = 0到+1.5 kJ/mol),与气相分散效应相反.
- 分散力被溶剂减弱,导致一种由交换排斥主导的趋势.
- 这些相互作用在高solvophobicity,低极化性溶剂中不那么不利.
- 素⋅⋅⋅接触总是不如甲基⋅⋅⋅接触 (ΔG = 0 到 -1.4 kJ/mol).
结论:
- 溶剂的影响显著改变素⋅⋅⋅相互作用的性质和强度.
- 交换排斥,而不是分散,决定了溶液的趋势,随着素大小的增加而增加.
- 甲基⋅⋅⋅相互作用本质上比溶液中的基⋅⋅⋅相互作用更有利.
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