在Dihydroazulene中超快激发状态的芳香化
Svetlana Shostak1, Woojin Park1, Juwon Oh2
1Department of Chemistry, Kyungpook National University, Daegu 41566, South Korea.
Journal of the American Chemical Society
|January 12, 2023
概括
双素 (DHA) 的光化学环开放涉及激发状态的芳香化. 非adiabatic动态显示主要途径增加芳香度和控制产品产量的小反贝尔德通道.
科学领域:
- 摄影化学
- 理论化学
- 化学动力学
背景情况:
- 酸 (DHA) 经历光化学环开放.
- 了解激发状态的动态对于控制反应路径至关重要.
研究的目的:
- 调查DHA光化学环开放过程中的兴奋状态芳香化动态.
- 探索芳香性和非芳香性作用在反应机制中的作用.
- 识别和描述小反应道及其对产品分销的影响.
主要方法:
- 没有反应的分子动力学模拟
- 混合参考旋转翻转时间依赖密度函数理论 (MRSF-TDDFT) 方法.
主要成果:
- 主要反应道涉及逐步增加芳香度,形成半芳香S1最小值.
- 超快的湿结长交替 (BLA) 和部分平面化是初始环开口的特征.
- 发现了具有较高屏障的轻微抗贝尔德通道,导致DHA重构或闭环产品.
结论:
- 在激发状态下,BLA的抑制是芳香键平衡过程的关键特征.
- 贝尔德和反贝尔德道之间的竞争影响了光化学产品的量子产量.
- 应纳入反贝尔德芳香度的概念,以扩大贝尔德规则的适用性.
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