Overall rate constant measurements of the reactions of alkene-derived hydroxyalkylperoxy radicals with nitric oxide

Abstract

The overall rate constants of the NO reaction with hydroxyalkylperoxy radicals derived from the OH-initiated oxidation of several atmospherically abundant alkenes-ethene, propene, 1-butene, 2-butene, 2-methyl propene, 1,3-butadiene, and isoprene (2-methyl-1,3-butadiene)-were determined using the turbulent flow technique and pseudo first-order kinetic conditions with high pressure chemical ionization mass spectrometry for the direct detection of hydroxyalkylperoxy radical reactants. The individual 100 Torr, 298 K rate constants for each alkene system were found to be identical within the 95% confidence interval associated with each separate measurement. The average overall rate constant for the reaction of all alkene-derived hydroxyalkylperoxy radicals with NO was determined to be 9.1 AE 0.5 (2s) Â 10 À12 cm 3 molecule À1 s À1 . Previous studies of this reaction for the ethene, 2-methyl propene and isoprene systems reported varying rate constant values that ranged from a factor of two lower to a factor of two higher than the present result. However, the invariant nature and value of the present rate constant determination closely parallels the results obtained in the measurement of rate constants for the reactions of several alkane-derived peroxy radicals with NO.

Direct kinetics study of the product‐forming channels of the reaction of isoprene‐derived hydroxyperoxy radicals with NO

“…1 and is similar to that described by Miller et al in their study of the overall reaction rate of alkene-derived hydroxyperoxy radicals with NO [15]. The main flow tube was 100 cm in length and constructed with 2.2-cm-inner-diameter Pyrex tubing.…”

Laboratory studies of organic peroxy radical chemistry: an overview with emphasis on recent issues of atmospheric significance

“…A notable exception is the acylperoxy radicals, RC(O)OO•, whose reactions with NO are rather rapid, ≈ 2 × 10 -11 cm 3 molecule -1 s -1 . Miller et al 49 conducted a systematic study of a number of C 2 -C 5 hydroxy-peroxy species obtained from the OH-initiated oxidation of alkenes, e.g.,…”

“…Among the systems studied was isoprene, which has While most measurements conducted to date have been for the atmospherically-relevant distribution of radicals generated in the OH/isoprene/O 2 , Ghosh et al 62 studied a subset of these radicals (the second through fourth radical from the left in the scheme above) via photolysis of an appropriate iodo-substituted isoprene analog. The IUPAC panel 60 recommends a rate coefficient k = 8.8 × 10 -12 cm 3 molecule -1 s -1 for the entire suite of radicals generated from OH addition to isoprene, based largely on the direct study of Miller et al 49 The data from Ghosh et al 62 for the subset of radicals generated in their experiments are essentially identical to this value ( A faster rate coefficient has been reported for the reaction of the peroxy species derived from the cyclic diether, 1,4-dioxane, k = 12 × 10 -12 cm 3 molecule -1 s -1 . 65 Recently, Elrod 55 reported a rate coefficient for reaction of NO with bicyclic peroxy radicals derived from the oxidation of 1,3,5trimethylbenzene, that was similar to those observed for simple systems, k = 7.7 × 10 -12 cm 3 molecule -1 s -1 .…”

Estimation of rate coefficients and branching ratios for reactions of organic peroxy radicals for use in automated mechanism construction

“…Group recommendation (http://iupac.pole-ether.fr/); b Based onEberhard and Howard (1996;,Eberhard et al (1996); c Based onMiller et al (2004); d Mixture of CH2(OH)CH(O2)CH3 and CH2(O2)CH(OH)CH3; e Mixture of CH2(OH)CH(O2)C2H5 and CH2(O2)CH(OH)C2H5; f Mixture of CH2(OH)C(O2)(CH3)2 and CH2(O2)C(OH)(CH3)2; g Mixture of CH2(OH)CH(O2)CH=CH2, CH2(OH)CH=CHCH2O2 and CH2(O2)CH(OH)CH=CH2; h Mixture of CH2(OH)C(O2)(CH3)CH=CH2, CH2(OH)C(CH3)=CHCH2O2, CH2(O2)C(CH3)(OH)CH=CH2, CH2(OH)CH(O2)C(CH3)=CH2, CH2(OH)CH=C(CH3)CH2O2 and CH2(O2)CH(OH)C(CH3)=CH2; i Based onSehested et al (1998); j Based onHsin and Elrod (2007); k Mixture of CH2(OH)C(O2)(CH3)CHO and CH2(O2)C(OH)(CH3)CHO; l Mixture of CH2(OH)CH(O2)C(=O)CH3 and CH2(O2)CH(OH)C(=O)CH3; mElrod (2011). Mixture of two complex radicals of molecular formula HOC9H12[OO]O2, although with one isomer likely dominant; n deGouw and Howard (1997); o Berndt et al…”