Mechanistic Insights into the OH-Initiated Oxidation of CF₃C(O)CH₂COCH₃: A Quantum Study

A detailed quantum chemical study was carried out to unravel the reaction mechanism, kinetics, and thermochemistry governing the gas-phase oxidation of 1,1,1-trifluoro-pentane-2,4-dione (CF₃C(O)CH₂C(O)CH₃, TFP) by hydroxyl (OH) radicals, employing the M06-2X density functional. The most thermodynamically stable conformer of TFP was identified under ambient conditions. Two predominant hydrogen-abstraction channels were characterized, both involving the formation of pre-reactive complexes, thereby indicating an indirect abstraction mechanism. Temperature-dependent rate coefficients for these pathways were computed for the first time over the 250–450 K temperature range using Canonical Transition State Theory (CTST). Based on the calculated kinetic parameters, the atmospheric lifetime of TFP was estimated to be approximately 30.44 days.