Kinetics of the Gas-Phase Reactions of OH and NO3 Radicals and O3 with Allyl Alcohol and Allyl Isocyanate

Rate constants for the gas-phase reactions of OH radical, NO3 radical, and ozone with allyl alcohol (AAL) and allyl isocyanate (AIC) have been measured using relative rate methods at atmospheric pressure in purified air. The experimental Arrhenius expression obtained for the reaction of the OH radical with AAL is (1.68 ± 0.89) × 10−12 × exp(1100/T) cm3 molecule−1 s−1, for T = 282−315 K; the Arrhenius expression for the reaction of OH radical with AIC is (1.94 ± 1.04) × 10−14 × exp(2207/T) cm3 molecule−1 s−1, for T = 282−317 K, where the indicated errors are one least-squares standard deviation. All OH radical reaction rate constants have been measured relative to k(OH + α-pinene) and k(OH + 1,3,5-trimethylbenzene). The rate constant for the gas-phase reaction of OH radical with allyl alcohol-d 6 isotopomer (AAL-d 6) has been measured at T = 298 K, and the value is 5.10 × 10−11 cm3 molecule−1 s−1. The kinetic isotope effect is small, with k(AAL)/k(AAL-d 6) = 1.32. Rate constants for the gas-phase reactions of NO3 radical with AAL [relative to k(NO3 +methacrolein)] and O3 [relative to k(O3 + β-pinene)] have been measured, and the values are 7.7 × 10−15 cm3 molecule−1 s−1 at T = 298 K and 1.6 × 10−17 cm3 molecule−1 s−1 at T = 296 K, respectively. Rate constants for the gas-phase reactions of NO3 radical and O3 with AIC have been measured, and the values are 9.4 × 10−16 cm3 molecule−1 s−1 at T = 299 K and 5.54 × 10−18 cm3 molecule−1 s−1 at T = 299 K, respectively. Multireference ab initio calculations at the MRMP2/6-311G(d,p) level have been carried out for reactions of OH radical with AAL and AIC. Results indicate that prereactive hydrogen bonded complexes form in the entrance channels for these reactions.