Production of OH radicals from the reactions of C4-C6 internal alkenes and styrenes with ozone in the gas phase

OH formation from the ozonolysis reactions of seven internal alkenes with 4-6 carbons, styrene. traps-beta-methyl styrene, and alpha-methyl styrene was studied using complementary techniques. A small-ratio relative-rate technique in which small quantities of OH tracers are added to monitor OH formation yields provided the following results: traps-2-butene, 0.64 +/- 0.12; cis-2-butene, 0.33 +/- 0.05; trans-2-pentene, 0.46 +/- 0.08; cis-2-pentene, 0.29 +/- 0.06; trans-3-hexene, 0.53 +/- 0.08; cis-3-hexene, 0.36 +/- 0.07; and 2-methyl-2-butene, 0.98 +/- 0.24. For styrene, trans-beta-methyl styrene, and alpha-methyl styrene, OH yields of 0.07 +/- 0.04, 0.22 +/- 0.09, and 0.23 +/- 0.12 were measured, respectively. A second method, which monitors product formation from the OH reaction with 2-butanol was used to derive OH formation yields from 2,3-dimethyl-2-butene, 2-methyl-2-butene and cis-2-pentene. and provided yields of 0.91 +/- 0.14, 0.80 +/- 0.12, and 0.27 +/- 0.07, respectively. The results are briefly discussed in terms of the relationship between structures of these alkenes and OH formation. (C) 2002 Elsevier Science Ltd. All rights reserved.