通过基替代剂稳定碳. 更大的更好吗?
H Lee Woodcock1, Damian Moran, Bernard R Brooks
1Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602-2525, USA. hlwood@nih.gov
Journal of the American Chemical Society
|March 1, 2007
概括
这项研究使用密度函数理论研究了碳稳定性. 较大的芳香替代剂增强了碳稳定性,影响了它们的电子和几何性质.
科学领域:
- 计算化学计算化学
- 量子化学 是一个量子化学.
- 有机化学 有机化学
背景情况:
- 碳是具有不同电子状态的反应性中间体.
- 基替代碳具有独特的稳定性和反应性模式.
- 了解碳电子结构对于合成应用至关重要.
研究的目的:
- 为了研究不同基替代碳化合物的单和三状态的几何和相对稳定性.
- 分析替代剂大小和类型对碳烯电子性质的影响.
- 为了将计算预测与单元-三元能量差距的实验数据进行比较.
主要方法:
- 密度函数理论 (DFT) 使用B3LYP/6-311+G(d,p) +ZPVE水平进行计算.
- 对,二,纳,二和替代碳化合物的研究.
- 包含单元-三元能量差距的经验纠正.
主要成果:
- 计算的单元-三元能量分离 (DeltaEST) 在经验校正后与实验值有很好的一致性.
- 三重组二9-甲基) 碳呈现出具有显著二基性质的烯结构.
- 响应稳定性随着较大的芳香替代剂 (例如,纳 > ) 的增加.
- 立体效应和轨道相互作用影响碳化合物几何和键长度.
结论:
- DFT计算准确地预测了基碳化合物的单元-三元能量差距.
- 更大的芳香替代剂为单基和三基碳提供了更大的共振稳定性.
- 碳基的几何结构是通过固态阻碍和电子相互作用与芳香环来调节的.
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