The supporting information includes:
Figures SI-1 to SI-4: Plots of the kinetic data for the alkyl esters according to eq (1) in the manuscript.
Fig SI-1 Examples of plots of the kinetic data for the reactions of Cl atoms with ethyl butanoate, ethyl propanoate, and ethyl ethanoate relative to the reaction of Cl with ethene obtained at (298 ± 2) K and atmospheric pressure using in situ FTIR for the analysis
Fig SI-2 Examples of plots of the kinetic data for the reactions of Cl atoms with isopropyl ethanoate, 1,1-dimethyl ethylethanoate, methyl-2,2-methylpropanoate, methyl-3-methylbutanoate and ethyl-3-methylbutanoate relative to the reaction of Cl with ethene obtained at (298 ± 2) K and atmospheric pressure using in situ FTIR for the analysis
Fig SI-3 Examples of plots of the kinetic data for the reactions of Cl atoms with pentyl ethanoate, butyl ethanoate, propyl ethanoate, propyl propanoate and methyl-2-methylpentanoate relative to the reaction of Cl with ethene obtained at (298 ± 2) K and atmospheric pressure using in situ FTIR for the analysis
Fig SI-4 Examples of plots of the kinetic data for the reactions of Cl atoms with ethyl propanoate, ethyl-2-methylpropanoate, and ethyl-2-2-dimethylpropanoate relative to the reaction of Cl with ethene obtained at (298 ± 2) K and atmospheric pressure using in situ FTIR for the analysisTable
Table SI.1. Comparison of experimental rate coefficients, kexp, determined in this work forthe reaction of Cl atoms with thosecalculatedusing SAR relationships. The rate coefficients are in units of 10-11 cm3 molecule-1 s-1. The kSAR values are those given in Table 2 in the main text. The kSAR_NEW are the values obtained using preliminary substituent factors derived from the rate coefficient measurements reported here and with the exception of F(-C(=O)OR are not recommendations.
Ester / k(this work) / kSARii) / kSAR_NEWii)
ethyl ethanoate / (1.71 ± 0.20) / 1.88 / 2.15
propyl ethanoate / (7.70 ± 0.83)
(7.35 ± 0.65)i) / 6.18 / 6.45
butyl ethanoate / (12.00 ± 1.62)
(13.23 ± 1.54)i) / 12.14 / 12.41
pentyl ethanoate / (17.90 ± 1.53) / 17.34 / 17.61
isopropyl ethanoate / (2.84 ± 0.35) / 2..33 / 2.60
tert-butyl ethanoate / (2.04 ± 0.23)
(1.75 ± 0.19) i) / 7.99 / 2.29
ethyl propanoate / (4.19 ± 0.48) / 4.70 / 3.68
propyl propanoate / (9.84 ± 1.18) / 10.01 / 9.07
methyl-2-methyl-propanoate / (3.72 ± 0.43)
(4.13 ± 0.38) i) / 5.70 / 4.61
ethyl-2-methyl-propanoate / (6.08 ± 0.67)
(6.56 ± 0.60) i) / 7.23 / 6.14
methyl-2,2-dimethyl-propanoate / (3.76 ± 0.33)
(3.79 ± 0.40) i) / 8.08 / 3.81
ethyl-2,2-dimethyl-propanoate / (5.35 ± 0.56) / 9.61 / 5.34
ethyl butanoate / (10.45 ± 0.84) / 11.22 / 7.71
methyl-3-methyl-butanoate / (8.07 ± 1.11)
(10.64 ± 1.09) i) / 10.53 / 8.17
ethyl-2-methyl-butanoate / (14.10 ± 1.19) / 13.77 / 11.94
ethyl-3-methyl-butanoate / (12.50 ± 1.41)
(12.84 ± 0.65) i) / 12.06 / 9.70
methyl-2-methyl-pentanoate / (13.97 ± 1.59) / 17.44 / 16.57
ethyl-2-methyl-pentanoate / (17.20 ± 1.95) / 18.97 / 18.00
i)determined using GC-FID the other values were determined using FTIR
ii)calculated as described in the main text using the SAR of Aschmann and Atkinson (1995) and the substituent factors F(CH3C(O)O-) = 0.066, F(CH3C(O)OCH2-) = 0.36, and F(CH3C(O)OCH<) = 0.27 from Xing et al. (2009) and F(-CO-) = 0.04 from Cuevas et al. (2005).
iii)calculated using the SAR of Aschmann and Atkinson (1995) and the substituent factors: F(-CH2-C(O)OR) = 0.28 (derived from the rate coefficient for ethylpropanoate); F( >CHC(=O)OR) = 0.55 (derived from the rate coefficient for methyl-2-methylpropanoate); F(≥C-C(=O)OR) = 0.36 (derived from the rate coefficient for methyl-2,2-dimethylpropanoate); F(-C(=O)OR = 0.12 (described in text); RC(=O)OC≤ = 0.19 (described in text).