A computational study of the mechanism for the C6H5+CH2O reaction
- 化学化工－已发表论文 
The mechanism for the C6H5 + CH2O reaction has been investigated with hybrid density functional quantum-chemical and statistical theory calculations. The results reveal three possible reaction channels: (1) The abstraction reaction producing C6H6 + HCO; (2) addition to the C atom yielding C6H5CH2O and (3) addition to the O atom giving C6H5OCH2. The barriers for these 3 reactions, calculated at the B3LYP/aug-cc-pvtz level of theory using the geometry optimized with B3LYP/cc-pvdz are 0.8, 1.4 and 9.1 kcal mol(-1), respectively. The C6H5CH2O radical can fragment to form C6H5CHO + H with a barrier of 19.4 kcal mol(-1). It can also undergo isomerization reactions via two cyclic epoxy intermediates to give C6H5OCH2 with a maximum barrier of 20.4 kcal mol(-1). Transition-state theory calculations using the predicted energy barriers and structures for the rate constants of the abstraction reaction (1) lead to very good agreement with our recently measured values, while the result of RRKM calculations for the isomerization/decomposition of C6H5OCH2 to C6H5CHO + H also agrees quantitatively with available experimental data.