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用从头算方法在6-31G的水平上研究了丙酮酸和苯甲酰甲酸热分解反应的机理．反应过程中各驻点都进行MP2相关能校准．计算结果表明：这两个反应都是羟基氢经历五元环过渡态迁移到α-羰基氧上形成氢键中间体；然后氢键中间体直接分解成异构体和二氧化碳；最后异构体经历三元环过渡态异构化成相应的醛．其中氢迁是决速步骤．在MP2／6-31G／／HF／6-31G基础上，对应于这两个反应速控步骤的活化位垒分别是186．0kJ·mol-1和169．3kJ·mol-1．在传统过渡态理论的基础上，计算了这两个反应在一定温度范围内热速率常数，理论的计算结果与实验值有很好的吻合．
The mechanism of pyrolysis of pyruvic acid and benzoylformate was studied at the level of 6-31G by ab initio method. Each station in the reaction process is calibrated for MP2. The calculated results show that both of the reactions are the reaction of hydroxyl hydrogen to undergo transition from the five-membered ring to the α-carbonyl oxygen to form a hydrogen bond intermediate; then the hydrogen bond intermediate decomposes directly into the isomer and carbon dioxide; the last isomer undergoes The three-membered ring transition state isomerizes to the corresponding aldehyde. Which is the speed of hydrogen migration step. On the basis of MP2 / 6-31G // HF / 6-31G, the activation barriers corresponding to these two reaction rate control steps are 186.0 kJ · mol-1 and 169.3 kJ · mol-1, respectively. Based on the traditional transition state theory, the thermal rate constants of these two reactions are calculated in a certain temperature range. The calculated results are in good agreement with the experimental ones.