Tuazon Ernesto C, Atkinson Roger
Air Pollution Research Center, University of California, Riverside, California 92521, USA.
Environ Sci Technol. 2003 Aug 1;37(15):3339-41. doi: 10.1021/es034091m.
3-Hexene-2,5-dione [CH3C(O)CH=CHC(O)CH3] and other unsaturated 1,4-dicarbonyls are formed from the atmospheric photooxidations of aromatic hydrocarbons. We have reinvestigated the formation of methylglyoxal from the gas-phase reaction of OH radicals with 3-hexene-2,5-dione in the presence of NO at room temperature and atmospheric pressure of air using in situ Fourier transform infrared spectroscopy. No evidence for the formation of methylglyoxal was obtained, with the IR spectra showing that methylglyoxal is, at most, a minor reaction product with a molar formation yield of <10% (and more likely <1%). This confirms our earlier study (Tuazon et al. Environ. Sci. Technol. 1985, 19, 265) and suggests that the CH3C(O)CH(OH)CHO and CH3C(O)CH(OH)CH(ONO2)C(O)CH3 observed by Bethel et al. (Environ. Sci. Technol. 2001, 35, 4477) are the major first-generation reaction products.
3-己烯-2,5-二酮[CH3C(O)CH=CHC(O)CH3]和其他不饱和1,4-二羰基化合物是由芳烃的大气光氧化反应形成的。我们利用原位傅里叶变换红外光谱，在室温及空气常压下，重新研究了在NO存在的情况下，OH自由基与3-己烯-2,5-二酮的气相反应中甲基乙二醛的形成。未获得甲基乙二醛形成的证据，红外光谱表明甲基乙二醛至多是一种次要反应产物，摩尔生成产率<10%（更可能<1%）。这证实了我们早期的研究（图阿松等人，《环境科学与技术》，1985年，第19卷，第265页），并表明贝塞尔等人（《环境科学与技术》，2001年，第35卷，第4477页）观察到的CH3C(O)CH(OH)CHO和CH3C(O)CH(OH)CH(ONO2)C(O)CH3是主要的第一代反应产物。
