β-羟基酮热分解反应机理的理论研究(英文)

Theoretical Study on the Mechanism of the Thermal Decomposition of β-Hydroxy Ketones

采用理论计算的方法来研究β-羟基酮热分解反应机理.为了研究4-羟基-3-甲基-2-戊酮,4-羟基-2-戊酮和4-羟基-4-甲基-2-戊酮的热分解反应机理,采用密度泛函理论,在B3LYP/6-31G(d)水平上计算了反应中反应物、过渡态和产物的平衡构型和能量.结果表明:在反应中存在六元环过渡态,甲基对反应影响不大,并且计算结果与实验数据相吻合.

The thermal decomposition of fl-hydroxy ketones was investigated theoretically. To determine the reaction mechanism of the thermal decomposition of 4-hydroxy-3-methyl-2-pentanone, 4-hydroxy- 2-pentanone and 4-hydroxy-4-methyl-2-pentanone, geometries, structures, and energies were evaluated for reactants, products, and transition states by using the density functional theory （DFT） at the B3LYP/6- 31G （d） level. The results indicate that the reaction involves a cyclic transition state, and the methyl groups do not have a great influence on the decomposition of them. These calculated results seem to support the experimental results observed at the thermal decomposition of β-hydroxy ketones by using kinetics.