在非碳化合物过氧激素中的转移反应
Josefine E Borcher1, Vili-Taneli Salo1, Thomas Golin Almeida1
1Department of Chemistry, University of Copenhagen, Universitetsparken 5, Copenhagen Ø DK-2100, Denmark.
The journal of physical chemistry. A
|February 2, 2026
概括
异原子显著加速有机过氧基中的转移反应,影响氧化分子的形成. 这影响了大气化学中的二次有机气溶形成.
科学领域:
- 大气化学 大气化学
- 化学动力学 化学动力学
- 有机化学 有机化学
背景情况:
- 转移反应是挥发性有机化合物 (VOC) 自氧化过程中的关键步骤.
- 这些反应形成高氧化有机分子 (HOM),有助于二次有机气溶 (SOA).
- 碳化合物过氧激素 (RO2) 中的H转移化学已知,但异原子效应尚未研究.
研究的目的:
- 研究异构原子 (O,N,S,P) 对过氧基 (RO2) 中的H转移反应的影响.
- 为了计算含有异原子的RO2基的H转移速率系数.
- 了解异质原子位置如何影响H转移反应性和选择性.
主要方法:
- 使用了多变形器过渡状态理论方法.
- 计算了各种含有异原子的RO2基的H转移速率系数.
- 分析了对反应趋势的立体,感应和立体电子效应.
主要成果:
- 发现 heteroatoms 加快 H-shift 反应,特别是当定位阿尔法到抽象地点时.
- 与β定位异构原子的反应显示出与碳化合物相似的速度.
- 与碳化合物相比,涉及异质原子的大型H转移跨度导致了更快的反应.
- 对于以太,1,8 H-shift 和 1,5 H-shift 的速度一样快,与双分子反应相竞争.
结论:
- 异构原子的结合显著改变了H转移反应速率和RO2基的选择性.
- 涉及非碳化合物过氧基的异构反应在大气化学中至关重要.
- 结果提供了对HOM形成和SOA生产途径的见解.
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