Organosulfates from Dark Aqueous Reactions of Isoprene-Derived Epoxydiols Under Cloud and Fog Conditions: Kinetics, Mechanism, and Effect of Reaction Environment on Regioselectivity of Sulfate Addition
Organosulfates from Dark Aqueous Reactions of Isoprene-Derived Epoxydiols Under Cloud and Fog Conditions: Kinetics, Mechanism, and Effect of Reaction Environment on Regioselectivity of Sulfate Addition
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云雾条件下异戊二烯衍生环氧二醇的暗水反应生成有机硫酸盐：动力学、机理以及反应环境对硫酸盐加成区域选择性的影响
DOI：
10.1021/acsearthspacechem.0c00293
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发表时间：
2021
影响因子：
3.4
通讯作者：
Turpin, Barbara J.
中科院分区：
文献类型：
--
作者：
Petters, Sarah S.;Cui, Tianqu;Zhang, Zhenfa;Gold, Avram;McNeill, V. Faye;Surratt, Jason D.;Turpin, Barbara J.
异戊二烯的大气氧化产生大量的高度水溶性的异戊二烯环氧二醇（IEPOX），其分成雾、云和湿气溶胶。在含水气溶胶中，IEPOX的酸催化开环，然后无机硫酸盐或水的亲核加成，分别形成有机硫酸盐和2-甲基四醇，大大有助于二次有机气溶胶（SOA）。然而，IEPOX在云、雾和蒸发性水凝物中的命运还不清楚。在这里，我们调查的速率，产品的分支比，和有机硫酸盐的立体化学反应稀IEPOX（5-10 mM）在一系列的硫酸盐浓度（0.3-50 mM）和pH值（1.83-3.38），以更好地了解IEPOX在云和雾的命运。从β-IEPOX异构体（反式和顺式-2-甲基-2，3-环氧丁烷-1，4-二醇）（主要的IEPOX异构体）的这些水性暗反应中，使用亲水相互作用液相色谱法与以负离子模式运行的电喷雾电离高分辨率四极杆飞行时间质谱仪（HILIC/（−）ESI-HR-QTOFMS）偶联，对产物进行鉴别和定量。结果表明，pH值对产物的区域化学和立体化学均有影响，提高溶液酸度有利于生成叔甲基四醇硫酸酯（C_5H_（12）O_7S）。此外，IEPOX在云相关条件下的反应速率常数比文献中报道的气溶胶相关条件低1个数量级，这是由于溶液活性明显不同。然而，在较低的水相pH值（模型估计）或液滴蒸发（未研究）的情况下，云和雾的水反应对IEPOX SOA的贡献可能是显着的。
Atmospheric oxidation of isoprene yields large quantities of highly water-soluble isoprene epoxydiols (IEPOX) that partition into fogs, clouds, and wet aerosols. In aqueous aerosols, the acid-catalyzed ring-opening of IEPOX followed by nucleophilic addition of inorganic sulfate or water forms organosulfates and 2-methyltetrols, respectively, contributing substantially to secondary organic aerosol (SOA). However, the fate of IEPOX in clouds, fogs, and evaporating hydrometeors is not well understood. Here we investigate the rates, product branching ratios, and stereochemistry of organosulfates from reactions of dilute IEPOX (5–10 mM) under a range of sulfate concentrations (0.3–50 mM) and pH values (1.83–3.38) in order to better understand the fate of IEPOX in clouds and fogs. From these aqueous dark reactions of β-IEPOX isomers (trans- andcis-2-methyl-2,3-epoxybutane-1,4-diols), which are the predominant IEPOX isomers, products were identified and quantified using hydrophilic interaction liquid chromatography coupled to an electrospray ionization high-resolution quadrupole time-of-flight mass spectrometer operated in negative ion mode (HILIC/(−)ESI-HR-QTOFMS). We found that the regiochemistry and stereochemistry were affected by pH, and the tertiary methyltetrol sulfate (C5H12O7S) was promoted by increasing solution acidity. Furthermore, the rate constants for the reaction of IEPOX under cloud-relevant conditions are up to 1 order of magnitude lower than reported in the literature for aerosol-relevant conditions due to a markedly different solution activities. Nevertheless, the contribution of cloud and fog water reactions to IEPOX SOA may be significant in cases of lower aqueous-phase pH (model estimate) or during droplet evaporation (not studied).
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影响因子：
6.3
作者：
Rattanavaraha W;Chu K;Budisulistiorini SH;Riva M;Lin YH;Edgerton ES;Baumann K;Shaw SL;Guo H;King L;Weber RJ;Neff ME;Stone EA;Offenberg JH;Zhang Z;Gold A;Surratt JD
通讯作者：
Surratt JD
影响因子：
15
作者：
LONG, FA;PRITCHARD, JG
通讯作者：
PRITCHARD, JG
影响因子：
5
作者：
Hughes, Dagen D.;Christiansen, Megan B.;Stone, Elizabeth A.
通讯作者：
Stone, Elizabeth A.
从特定的氧鎓离子催化到通用酸催化的转变1
DOI：
--
发表时间：
1952
期刊：
影响因子：
--
作者：
C. G. Swain
通讯作者：
C. G. Swain
DOI：
--
发表时间：
1972
期刊：
影响因子：
--
作者：
Arthur L. Mori;L. Schaleger
通讯作者：
L. Schaleger