raisopropylmethane 和 tetracyclopropylmethane 的构成动态以及它们的构成动态
J Edgar Anderson1, Armin De Meijere, Sergei I Kozhushkov
1Chemistry Department, University College, Gower Street, London, WC1E 6BT, UK. j.e.anderson@ucl.ac.uk
Journal of the American Chemical Society
|June 6, 2002
概括
二甲以两种形式存在,其中D2d形式主导. 环甲完全采用S4构造,揭示了分子动力学和构造分析的洞察力.
科学领域:
- 有机化学 有机化学
- 计算化学计算化学
- 频谱学是一种光谱学.
背景情况:
- 了解分子构造对于预测化学性质和反应性至关重要.
- raisopropylmethane 和 tetracyclopropylmethane 是用于研究基的固态效应的模型系统.
研究的目的:
- 为了研究四西甲和四cyclopropylmethane的构造景观和动态.
- 描述这些分子中构造性相互转换的能量障碍.
- 将实验结果与分子力学计算进行比较.
主要方法:
- 低温核磁共振 (NMR) 光谱 (1H和13C).
- 分子力学 (MM) 的计算.
- 分析NMR信号的多重性和化学转移.
主要成果:
- 二甲存在于D2d (93%) 和S4 (7%) 适配物的混合物,温度为-110°C,具有9.7 kcal的mol-1相互转换屏障.
- 四环甲完全填充了S4形状.
- cyclopropylmethane的S4对应体的相互转换障碍是4.5kcalmol-1. 这就是4.5kcalmol-1.
- 分子力学计算准确地预测了形状偏好和障碍.
结论:
- 这项研究阐明了四西甲和四cyclopropylmethane的主导符合性和相互转化动态.
- 实验和计算结果显示出良好的一致性,验证了采用的方法.
- 形态分析为高度替代的基中固态相互作用提供了宝贵的见解.
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