Rate constants for the reactions of Cl atoms with a series of C₆–C₁₀ cycloalkanes and cycloketones at 297 ± 2 K

Abstract

Rate constants for the reactions of Cl atoms with cycloheptane, cyclooctane, cyclodecane, cyclohexanone, cycloheptanone, cyclooctanone, and cyclodecanone have been measured at 297 ± 2 K and atmospheric pressure of air using a relative rate method. n-Butane, with a rate constant of 2.05 × 10 −10 cm 3 molecule −1 s −1 , was used as the reference compound, and the rate constants obtained (in units of 10 −10 cm 3 molecule −1 s −1 ) were cycloheptane, 4.22 ± 0.15; cyclooctane, 4.57 ± 0.15; cyclodecane, 5.13 ± 0.15; cyclohexanone, 1.79 ± 0.06; cycloheptanone, 2.46 ± 0.07; cyclooctanone, 2.97 ± 0.09; and cyclodecanone, 3.65 ± 0.15, where the indicated errors are two least-squares standard deviations and do not include uncertainties in the rate constant for the reference compound n-butane. Room temperature rate constants for the C 5 -C 10 cycloketones indicate that the CH 2 groups adjacent to the carbonyl group are almost totally deactivated toward H-atom abstraction by Cl atoms, and this also applies to acyclic ketones. A previous structure-reactivity relationship for Cl + alkanes has been extended to include acyclic and cyclic ketones.

Relative Rate Studies of the Reactions of Atomic Chlorine with Acetone and Cyclic Ketones

“…It may be seen that where comparison is possible our measurements agree with the literature, that is, for reactions of atomic Cl with acetone and cycloheptanone . Figure shows a comparison between measured rate constants for Cl plus cycloketones and SAR values by Farrugia et al as a function of ring size.…”

“…Comparison of measured rate constants for Cl + cycloketones with values obtained from SAR parameterization. Solid circles, present work; solid square, Takahashi et al ; open circles, ; solid line, SAR from Farrugia et al .…”

“…Wallington et al and Takahashi et al measured Cl plus cyclopentanone and cyclohexanone. The work of Aschmann and Atkinson on Cl plus cycloalkanes and cycloketones included analysis in terms of structure–activity relationships (SAR). These were modified by Farrugia et al , who also highlighted some discrepancies in the prior literature.…”

Geminal Diol Formation from the Interaction of a Ketone with Water in the Gas Phase: Structure and Reactivity of Cyclooctanone-(H2O)1,2 Clusters

“…CYO can be produced from reactions of cyclooctane with OH radicals in the atmosphere. The rate constants of CYO reactions with OH radicals and Cl atoms have been measured. , …”

“…The rate constants of CYO reactions with OH radicals and Cl atoms have been measured. 26,27 The rotational spectrum of CYO with water in the 2−8 GHz frequency range was collected using our broadband rotational spectrometer. 28,29 Once the lines from the observed conformers of CYO 25 were removed from the spectrum, spectral patterns associated with other species emerged.…”