链分子优先分支的轨道阶段控制
1Department of Chemistry, Faculty of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan.
Journal of the American Chemical Society
|July 18, 2001
概括
轨道相理论解释了为什么E(4) H(10) 的分支异构体 (如和) 比正常异构体更稳定. 这一发现得到了计算和实验数据的证实,广泛适用于碳化合物异构体稳定性.
科学领域:
- 计算化学计算化学
- 有机化学 有机化学
- 量子化学 是一个量子化学.
背景情况:
- 了解控制化学异构体相对稳定的因素在有机化学和计算化学中至关重要.
- 分支异构体与它们的线性对应物相比,往往表现出不同的特性,需要进行理论和实验研究.
研究的目的:
- 调查轨道相理论的适用性,以预测E(4) H(10) (其中E = C,Si,Ge,Sn) 的分支与正常同位素的相对稳定性.
- 将轨道相理论的应用扩展到其他和同体,并将其预测能力概括.
主要方法:
- 轨道相理论的应用.
- 一开始的分子轨道 (MO) 计算.
- 密度函数理论 (DFT) 的计算.
- 与现有的实验结果进行比较.
主要成果:
- 轨道相理论成功地预测了分支异构体对E(4) H(10) 的正常异构体的偏好稳定性.
- 计算和实验数据证实了来自轨道相理论的预测.
- 该理论被扩展,以解释对新坦类比异布坦类分支的偏好,对内甲基分支的终端偏好,以及在较长的基中对乙基替代的甲基偏好.
- 该理论还预测,异布丁基比2 - 布丁基更喜欢异布丁基.
结论:
- 轨道相理论为理解和预测分支碳化合物异构体的增强稳定性提供了一个一般的框架.
- 分支异构体的优先稳定是一种由轨道相关系控制的一般现象.
- 这项工作验证了轨道相理论作为预测有机分子中异构分子偏好的强大工具.
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