从激活菌株的角度来看,1,3-cyclopentadiene的三元化中的选择性的起源
Ravshan S Shamsiev1, Nikolai A Dontsenko2
1Lomonosov Institute of Fine Chemical Technologies, MIREA-Russian Technological University, 86 Vernadsky Avenue, 119571, Moscow, Russian Federation. shamsiev.r@gmail.com.
Journal of molecular modeling
|September 3, 2024
概括
量子化学建模揭示了1,3-cyclopentadiene (CPD) 与dicyclopentadiene (DCPD) 的外加是动力学上受青的. 立体效应和分子变形在CPD三元体形成中显著影响循环添加反应障碍.
科学领域:
- 化学反应 化学反应
- 计算化学的计算化学
- 有机化学 有机化学
背景情况:
- 调查了1,3-cyclopentadiene (CPD) 和dicyclopentadiene (DCPD) 之间的 [4+2]-环添加反应.
- 检查了14种不同的CPD剪裁产品的形成.
- 考虑了CPD到DCPD的异位和内附途径.
研究的目的:
- 为了确定CPD三元体形成的动态偏好反应途径.
- 为了计算和分析产生的剪裁器的环张力能量 (ERS).
- 阐明固体效应和分子变形在循环添加反应机制中的作用.
主要方法:
- 使用密度函数理论 (DFT) 使用PBE0函数和cc-pVTZ基础集的量子化学建模.
- 用Gaussian 09软件进行了计算.
- 使用同位体反应方法来计算环张力能量.
主要成果:
- 识别了CPD对DCPD的norbornene片段的CPD外加和对环烯片段的转加作为动力学上受青的.
- 确定压力最小的剪裁器是由外加到外DCPD产生的,而压力最大的则是由内加到内DCPD产生的.
- 揭示了在过渡状态下DCPD的硬体效应和变形是激活屏障大小的主要驱动因素.
结论:
- CPD剪裁器的动力和热力学稳定性与计算的环张力能量相关.
- 激活菌株模型有效地解释了固态因素和分子几何变化对反应速率的影响.
- DCPD分子的二面角变形是循环加法激活能的一个关键决定因素.
关键词:
1,3-环旋二烯的使用方法激活应变模型的激活应变模型循环添加 循环添加狄基clopentadiene 的使用方法环张力能量 环张力能量过的碳化合物 过的碳化合物三cyclopentadiene 的使用情况.更多相关视频
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