Gas phase reaction of the hydroxyl radical with the unsaturated peroxyacyl nitrate CH2C(CH3)C(O)OONO2

The gas phase reaction of the hydroxyl radical with the unsaturated peroxyacyl nitrate CH2  C(CH3)C(O)OONO2 (MPAN) has been studied at 298 ± 2 K and atmospheric pressure. The OH‐MPAN reaction rate constant relative to that of OH + n‐butyl nitrate is 2.08 ± 0.25. This ratio, together with a literature rate constant of 1.74 × 10−12 cm3 molecule−1 s−1 for the OH + n‐butyl nitrate reaction at 298 K, yields a rate constant of (3.6 ± 0.4)× 10−12 cm3 molecule−1 s−1 for the OH‐MPAN reaction at 298 ± 2 K. Hydroxyacetone and formaldehyde are the major carbonyl products. The yield of hydroxyacetone, 0.59 ± 0.12, is consistent with preferential addition of OH at the unsubstituted carbon atom. Atmospheric persistence and removal processes for MPAN are briefly discussed.