PRODUCTS AND MECHANISMS OF THE GAS-PHASE REACTIONS BETWEEN NO3 AND A SERIES OF ALKENES

Products and mechanisms for the gas-phase reactions of NO3 radicals with a series of alkenes in air have been studied. The experiments with propene, isobutene, trans- and cis-2-butene, 2-methyl-2-butene, and 2,3-dimethyl-2-butene were carried out at 295 ± 2 K and 740 ± 5 Torr in a 480-L Teflon-coated reaction chamber where NO3 was generated by the thermal dissociation of N2O5. Reactants and products were observed to produce nitroxy-nitroperoxy intermediates that decayed with formation of carbonyl, nitroxycarbonyl, nitroxy alcohol, and dinitrate species. The product distribution was found to be dependent on the alkyl substitution pattern around the double bond. Evidence was also found of a reaction between NO3 and organic peroxy radicals with a rate constant measured in the case of the 2,3-dimethyl-2-nitroxy-3-peroxybutane radical to be of the order of 5 × 10-12 cm3 molecule-1 s-1. © 1990 American Chemical Society.