Theoretical studies on mechanism and kinetics of the hydrogen-abstraction reaction of CF3C(O)OCH2CH3 with OH radicals

Abstract The hydrogen-abstraction reaction of CF 3 C(O)OCH 2 CH 3  + OH has been studied theoretically by a dual-level direct dynamics method. For the two stable conformers (I, II) of CF 3 C(O)OCH 2 CH 3 , three distinct transition states are identified for the reaction of conformer I ( C s symmetry) + OH (R1), and five transition states are ascertained for the reaction of conformer II ( C 1 symmetry) + OH (R2). The potential energy surface information for the kinetic calculation is obtained at the MCG3-MPWB//M06-2X/aug-cc-pVDZ level. The rate constants for each reaction channel are calculated using improved canonical variational transition-state theory (ICVT) with small-curvature tunneling correction (SCT) and are fitted by a three-parameter Arrhenius equation within 200–1000 K. The calculated rate constant is in reasonable agreement with the experimental data at 298 K.