Conformational influence on the thermal rate constants and product distributions of 2-butanone + H abstraction reactions

Thermal rate constants and product branching ratios for the hydrogen abstraction reactions of 2-butanone by H-atom were estimated employing the multipath canonical variational theory with small-curvature tunneling (MP-CVT/SCT). Torsional anharmonicity due to the hindered rotors was included with the multistructural method based on a coupled torsional potential, MS-T(C). For comparisons, we also determined the rate coefficients with the single-structure and multipath approximations within the harmonic approximation. The overall MP-CVT/SCT thermal rate constants are in excellent agreement with the experimental estimation. The product distributions strongly depend on the recrossing, tunneling, multiple structures, and torsional anharmonicity effects.