Rusu Vasilache Ana-Maria, Roman Claudiu, Bejan Iustinian G, Arsene Cecilia, Olariu Romeo I
Department of Chemistry, Faculty of Chemistry, "Alexandru Ioan Cuza" University of Iasi, 11 Carol I, 700506 Iasi, Romania.
Integrated Centre of Environmental Science Studies in the North Eastern Region (CERNESIM), "Alexandru Ioan Cuza" University of Iasi, 11 Carol I, 700506 Iasi, Romania.
J Phys Chem A. 2024 Jun 20;128(24):4838-4849. doi: 10.1021/acs.jpca.4c02287. Epub 2024 Jun 10.
Five biogenic unsaturated alcohols have been investigated under simulated atmospheric conditions regarding their gas-phase OH reactivity. The gas-phase rate coefficients of OH radicals with 2-methyl-3-buten-2-ol (), 3-methyl-2-buten-1-ol (), 3-methyl-3-buten-1-ol (), 2-methyl-3-buten-1-ol (), and 3-methyl-3-buten-2-ol () at 298 ± 2 K and 1000 ± 10 mbar total pressure of synthetic air were determined under low- and high-NO conditions using the relative kinetic technique. The present work provides for the first time the rate coefficients of gas-phase reactions of hydroxyl radicals with 2-methyl-3-buten-1-ol and 3-methyl-3-buten-2-ol. The following rate constants were measured (in 10 cm molecule s): = 6.32 ± 0.49, = 14.55 ± 0.93, = 10.04 ± 0.78, = 5.31 ± 0.37, and = 11.71 ± 1.29. No significant differences in the measured rate coefficients were obtained when either 365 nm photolysis of CHONO in the presence of NO or 254 nm photolysis of HO was used as a source of OH radicals. Reactivity toward other classes of related compounds such as alkenes and saturated alcohols is discussed. A comparison of the structure-activity relationship (SAR) estimates derived from the available accepted methodologies with experimental data available for unsaturated alcohols is provided. Atmospheric lifetimes for the investigated series of alkenols with respect to the main atmospheric oxidants are given and discussed.
在模拟大气条件下，对五种生物源不饱和醇的气相OH反应活性进行了研究。在298±2K和合成空气总压为1000±10毫巴的条件下，使用相对动力学技术，在低NO和高NO条件下，测定了OH自由基与2-甲基-3-丁烯-2-醇（）、3-甲基-2-丁烯-1-醇（）、3-甲基-3-丁烯-1-醇（）、2-甲基-3-丁烯-1-醇（）和3-甲基-3-丁烯-2-醇（）的气相速率系数。本工作首次提供了羟基自由基与2-甲基-3-丁烯-1-醇和3-甲基-3-丁烯-2-醇气相反应的速率系数。测量了以下速率常数（单位为10⁻¹²cm³·分子⁻¹·s⁻¹）： = 6.32±0.49， = 14.55±0.93， = 10.04±0.78， = 5.31±0.37， = 11.71±1.29。当使用在NO存在下CH₂ONO的365nm光解或H₂O的254nm光解作为OH自由基源时，测得的速率系数没有显著差异。讨论了对其他相关化合物类别的反应活性，如烯烃和饱和醇。提供了从现有公认方法得出的结构-活性关系（SAR）估计值与不饱和醇可用实验数据的比较。给出并讨论了所研究的一系列链烯醇相对于主要大气氧化剂的大气寿命。
