Rate constants for the reactions of chlorine atoms with a series of unsaturated aldehydes and ketones at 298 K: structure and reactivity

FTIR gas-phase kinetic study of the reactions of Cl atoms with (CH3)2CCHC(O)H and CH3CHCHC(O)OCH3

“…Furthermore, it should be noted that no significant differences are found between any of the experimental rate coefficients for the reactions of Cl atoms with the unsaturated aldehydes presented in Table 3 which shows that the reactivity toward Cl seems to be fairly independent of the substitution on the olefinic carbons for these unsaturated aldehydes. This tendency is difficult to explain since the contribution of the H-atom abstraction channel from the -CHO group to the overall rate coefficient is expected to be constant [19] and addition of methyl substituents would be expected to increase the reactivity, as observed for the unsaturated esters. The reactions are, however, fast and approaching collision controlled and it is possible that differences between the rate coefficients for changes in substitution may be minor and obscured by the experimental kinetic uncertainties.…”

“…For the reaction of Cl atoms with unsaturated aldehydes, in addition to H-atom abstraction from the -CHO group, a significant fraction of the reaction will also proceed by Cl addition to the double bond. The contribution of H-atom abstraction is around 30% for the unsaturated aldehydes discussed here [19].…”

Theoretical study of the Cl-initiated atmospheric oxidation of methyl isopropenyl ketone

“…As displayed in Table 2, all the kinetic data are in accord with their corresponding experimental values previously reported. [36][37][38][39][40] Compared all the addition channels of these four compounds, we can see that the rate constants of addition channels are k add-MACR > k add-ACR > k add-MIK > k add-MVK . Also, the total rate constants are k tot-MACR > k tot-ACR > k tot-MIK > k tot-MVK .…”

Development of a chlorine mechanism for use in the carbon bond IV chemistry model

“…The rate constant for the Cl + 1‐chloro‐3‐methyl‐3‐butene‐2‐one reaction is assumed to be the same as chloromethyl vinyl ketone. The rate of the surrogate reaction has been reported by Wang et al [2002] as 2 × 10 −10 cm 3 molecule −1 s −1 .…”

“…The Cl + BCL1 reaction is not included in the mechanism because it is not expected to be an important loss pathway. Assuming [OH] and [Cl] of 2.5 × 10 −6 and 5.0 × 10 −4 cm −3 and the reaction rate constants k OH,BCL1 = 3.6 × 10 −11 cm 3 molecule −1 s −1 and k Cl,BCL1 = 1.6 × 10 −10 cm 3 molecule −1 s −1 [ Wang et al , 2002], the lifetimes of BCL1 against OH· and Cl· are 3 and 35 hours, respectively.…”