立体电子相互作用太弱,无法解释cis-2-tert-butyl-5-(tert-butylsulfonyl) -1,3-dioxane在固态中的分子构造
Fátima M Soto-Suárez1, Tania Rojo-Portillo1, Eduardo H Huerta1
1Universidad Nacional Autónoma de México, Instituto de Química, Circuito Exterior, Ciudad Universitaria, Delegación Coyoacán, C.P. 04510 Ciudad de México, Mexico. gecgb@unam.mx.
Physical chemistry chemical physics : PCCP
|March 14, 2024
概括
固态中cis-2-tert-Butyl-5-(tert-butylsulfonyl) -1,3-dioxane的覆盖形状是通过CHOS分子间相互作用稳定的. 这一发现有助于使用固态分析来理解溶液中的过渡状态.
科学领域:
- 固态化学 固态化学
- 分子构造的分子构造.
- 超分子化学 超分子化学
背景情况:
- 在固态状态下,cis-2-tert-Butyl-5-(tert-butylsulfonyl) -1,3-dioxane (cis-1) 的覆盖形状是不寻常的,其起源是无法解释的.
- 这种固态构造类似于溶液中的过渡状态,为研究过渡状态结构提供了独特的机会.
研究的目的:
- 为了阐明 cis-1 固态中不寻常的阴影形状的起源.
- 研究分子间相互作用在稳定这种形状中的作用.
- 为了将固态形态行为与溶液相过渡状态联系起来.
主要方法:
- 在固态中对cis-1进行实验电子密度研究.
- 使用分子中的原子量子理论 (QTAIM) 进行电荷密度分析.
- 在cis-1及其trans同位素之间比较升华的度.
主要成果:
- 在cis-1和trans-1之间8.40kcalmol-1的升华差异 (ΔsubH) 的度表明晶格中存在显著的分子间力.
- 实验性电子密度分析确定了CHOS分子间相互作用作为cis-1中阴影化构造的主要稳定力.
- QTAIM分析证实了这些分子间相互作用在晶体结构中的性质和重要性.
结论:
- 在cis-1中观察到的阴影形状主要是由稳定CHOS在固态中的分子间相互作用驱动的.
- 了解这些固态相互作用,可以了解溶液中的过渡状态的性质.
- 这项研究强调了固态电荷密度分析对于理解分子构造和分子间力量的有用性.
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