Mechanism of the OH-initiated oxidation of methacrolein

Abstract

The OH-initiated oxidation of methacrolein, a major product of isoprene oxidation, has been studied in an environmental chamber using FT-IR spectroscopy. Products observed (which account for more than 90% of the reacted carbon) were CO, CO2, hydroxyacetone, formaldehyde, and methacryloylperoxynitrate (MPAN). It is determined that the attack of OH on methacrolein occurs 55% of the time via addition to the double bond, and 45% via abstraction of the aldehydic hydrogen atom, in agreement with a previous study. The end products of the abstraction channel are identified and quantified for the first time, and the mechanism of their production discussed. Copyright 1999 by the American Geophysical Union.