158475-28-6Relevant academic research and scientific papers
Thermal stability of peroxynitrates
Kirchner,Mayer-Figge,Zabel,Becker
, p. 127 - 144 (1999)
Peroxynitrates are thermally unstable intermediates (at ambient temperatures) in the atmospheric degradation of hydrocarbons. In this work, thermal lifetimes of nine peroxynitrates have been measured as a function of temperature and, for two of them, also, as a function of total pressure. In the presence of excess NO, relative concentrations of the peroxynitrates were followed in a 420 I reaction chamber as a function of time by means of long-path IR absorption using a Fourier transform spectrometer. Original data on the unimolecular decomposition rate constants are presented for the peroxynitrates RO2NO2 with R = C6H11, CH3C(O)CH2, C6H5CH2, CH2I, CH3C(O)OC(H)CH3, C6H5OCH2, (CH3)2NC(O), C6H5OC(O), and C2H5C(O). Thermal lifetimes at room temperature and atmospheric pressure are very short (in the order of seconds) for substituted methyl peroxynitrates (i.e., R′CH2O2NO2) but rather long for substituted formyl peroxynitrates (i.e., R″C(O)O2NO2). Kinetic data from this and previous work from our laboratory are used to derive structure-stability relationships which allow an estimate of the thermal lifetimes of peroxynitrates from readily available 13C n.m.r. shift data.
FTIR Spectroscopic Study of the Mechanism for the Gas-Phase Reaction between Ozone and Tetramethylene
Niki, H.,Maker, P. D.,Savge, C. M.,Breitenbach, L. P.,Hurley, M. D.
, p. 941 - 946 (2007/10/02)
Long-path FTIR spectroscoic product studies were made of mixtures containing part-per-million concentrations of O3 and (CH3)2C=C(CH3)2 (TME) in 700 Torr of O2-N2 to determine the formation and reactions of the dimethyl-substituted Criegee intermediate (CH3)2COO expected from O3 + TME -> (CH3)2COO + (CH3)2C=O.The observed stoichiometry, Δ-/Δ, was typically 1.7, and among the products were CO, CO2, HCHO, CH3OH, CH3OOH, CH3C(=O)OH, CH3C(=O)OOH, (CH3)2C=O, CH3C(=O)CHO, CH3C(=O)CH3, Ch3C(=O)CH2(OH), and products tentatively identified as (CH3)2C(OH)-C(CH3)2OOH and CH3C(=O)CH2(OOH).In addition, 16O- and 18O-labeled products were identified in 18O3-TME-air mixtures, and the effect of added HCHO, CH3CHO, and NO2 (or 15NO2) on the product distribution were determined.The results indicate that ca.25percent of the (CH3)2COO moiety formed was thermally stable, and that the remainder largely dissociated to yield the following free radicals, i.e., (CH3)2 -> CH3C(OOH)=CH2 -> CH3C(=O)CH2. + HO..The HO-initiated oxidation of TME was shown to account for the excess cosumption of TME over O3 as well as for some of the major products observed.
