三乙烯胺的高效自氧化
Eva R Kjærgaard1, Kristian H Møller1, Torsten Berndt2
1Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark.
The journal of physical chemistry. A
|October 6, 2023
概括
三乙胺 (TEA) 经历大气中的快速自氧化,形成高氧化产品. 这一过程比其他氨基酸更快,涉及高效的H转移反应,并通过实验观测得到证实.
科学领域:
- 大气化学 大气化学
- 有机化学 有机化学
- 化学动力学 化学动力学
背景情况:
- 自氧化是大气化合物如异烯和烯的关键氧化途径.
- 它也被确定为在二甲基硫化物 (DMS) 和三甲基胺 (TMA) 的氧化中占主导地位.
研究的目的:
- 研究大气中三乙烯胺 (TEA) 的自氧化机制.
- 为了确定OH + TEA之后的单分子反应和H转移过程的速度.
- 识别和验证高氧化产品的形成.
主要方法:
- 理论上的多变压器过渡状态理论 (MC-TST) 计算.
- 流管实验观察反应产物和激素.
主要成果:
- 三乙胺 (TEA) 呈现出异常快速的大气自氧化,超过了对DMS和TMA观察到的速度.
- 产品最多有三个氧基 (OOH) 组和O:C比率>1的产品形成.
- 对于前两代H-shift的速率系数超过20s-1.
- 在α-碳中,OH抽象得到了强烈的支持.
结论:
- 自氧化是TEA的主要大气氧化途径,导致高度功能化的化合物.
- 实验结果验证了理论预测和拟议的氧化产品和激素的形成.
- 这项研究强调了TEA自氧化在大气化学中的重要作用.
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