在热 [4 + 4] 循环添加 [2.2] (9,10) 炭烯的过程中体积变化
1Department of Chemistry, Georgetown University , 37th and O Streets, NW, Washington, D.C. 20057-1227, United States.
Journal of the American Chemical Society
|August 10, 2013
概括
这项研究揭示了通过迪拉基化过渡状态进行光二聚变的逐步反应路径. 这解释了压力诱导的利率提升,并提供了对债券转型的见解.
科学领域:
- 摄影化学的使用.
- 有机化学 有机化学
- 计算化学计算化学
背景情况:
- 连接的二甲-9,10-二甲) 经历光二分化.
- 了解反应机制和过渡状态对于控制化学反应至关重要.
研究的目的:
- 阐明绑定生物甲-9,10-二甲的光二分化反应路径和过渡状态.
- 为压力催化屏障降低和速度增强提供一个原子论解释.
- 在钻石到石墨过渡和旋风光异构化背景下讨论转化.
主要方法:
- 密度函数理论 (DFT) 用长距离校正进行计算.
- 分子体积和过渡状态结构的分析.
- 与压力催化和旋几何学的实验发现进行比较.
主要成果:
- 反应通过一个迪拉基化过渡状态 (TS) 逐步进行.
- TS的分子体积比反应物或产物要小,解释了压力效应.
- 这种转化与钻石转化为石墨的转化有相似之处.
结论:
- 迪拉基卡洛伊德TS为增强压力的光二分化速率提供了一种机理性的解释.
- 光异构体中的D2h对称是过渡结构,而不是平衡几何.
- 这项工作澄清了有关旋风光异构体平衡结构的争议.
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