过氧亚硝酸与苯酚的反应机理理论研究

采用量子化学密度泛函理论(DFT)研究了过氧亚硝酸分解产生的自由基(?OH和?NO2)与苯酚的反应机理. 在B3LYP/6-311++G(d, p)//B3LYP/6-311G(d, p)水平上对该反应体系的反应物、中间体、过渡态及产物进行了几何构型优化并计算了振动频率和能量. 计算结果表明, 过氧亚硝酸与苯酚的反应生成两种主要产物, 分别为邻羟基苯酚和对羟基苯酚, 这一结论与实验结果一致. 此外在同一计算水平上采用SCRF(PCM)方法计算了溶剂化效应, 结果表明, 极性溶剂可以降低各反应通道的活化能, 有利于反应的进行.

Theoretical Study on the Mechanisms of the Reaction of Peroxynitrous Acid and Phenol

The mechanisms of the reactions of the radicals (?OH and ?NO2) derived from peroxynitrous acid with phenol have been studied using density functional theory (DFT) at the B3LYP/6-311++G(d, p)//B3LYP/6-311G(d, p) level. The geometries of all the molecules were optimized, and the harmonic vibration frequencies and the energies were calculated as well. The calculation results show that the primary products of the reaction of peroxynitrous acid and phenol are o-hydroxyphenol and p-hydroxyphenol, due to their relatively lower activation barriers. The conclusion is in good agreement with the corresponding experimental data. In addition, the effects of solvents on these reactions were also investigated. The results suggest that polar solvents can reduce the activation energy and hence facillate the occurrence of reactions.