GAS-PHASE REACTION OF THE HYDROXYL RADICAL WITH THE UNSATURATED PEROXYACYL NITRATE CH2 = C(CH3)C(O)OONO2

The gas phase reaction of the hydroxyl radical with the unsaturated pe roxyacyl nitrate CH2 = C(CH3)C(O)OONO2 (MPAN) has been studied at 298 +/- 2 K and atmospheric pressure. The OH-MPAN reaction rate constant r elative to that of OH + n-butyl nitrate is 2.08 +/- 0.25. This ratio, together with a literature rate constant of 1.74 x 10(-12) cm3 molecul e-1 s-1 for the OH + n-butyl nitrate reaction at 298 K, yields a rate constant of (3.6 +/- 0.4) x 10(-12) cm3 molecule-1 s-1 for the OH-MPAN reaction at 298 +/- 2 K. Hydroxyacetone and formaldehyde are the majo r carbonyl products. The yield of hydroxyacetone, 0.59 +/- 0.12, is co nsistent with preferential addition of OH at the unsubstituted carbon atom. Atmospheric persistence and removal processes for MPAN are brief ly discussed. (C) 1993 John Wiley & Sons, Inc.