N-(邻氯苯基)苯甲酰胺在CuX(X=I,Br)催化下的分子内O-芳基化反应机理

Mechanism for the CuX-Catalyzed (X=I, Br) Intramolecular O-Arylation Reaction of N-(ortho-chlorophenyl)benzamide

采用密度泛函理论(DFT)中的B3LYP方法,在6-31+G*基组水平上研究了N-(邻氯苯基)苯甲酰胺在CuX(X=I,Br)催化下发生分子内O-芳基化的反应机理.优化了反应过程中的反应物、中间体、过渡态和产物,通过能量和振动分析证实了中间体和过渡态的真实性.并且在相同基组水平上应用自然键轨道(NBO)理论和分子中的原子(AIM)理论分析了这些化合物的成键特征和轨道间的相互作用.比较了两种不同铜盐催化剂的催化活性,计算结果表明两种催化剂的反应路径和反应的控制步骤完全相同,在CuBr催化下标题化合物控制步骤的活化能比在CuI催化下的低,证明了CuBr的催化活性要比CuI的高一些,与实验结果一致.

A mechanism for the intramolecular O-arylation reaction of N-（ortho-chlorophenyl）benzamide catalyzed by CuX（X=I, Br） was studied using the density functional theory at B3LYP/6-31＋G^＊ level. We optimized the geometric configurations of reactants, intermediates, transition states, and products. A vibrational analysis and an energy calculation proved the authenticities of the intermediates and the transition states. Nature bond orbital （NBO） and atoms in molecules （AIM） theories were used to discuss the bond nature and orbital interactions at the same levels. At the same time, we compared the influence of two different copper catalysts on the catalytic activity. Computation results indicate that they have the same reaction path and that the activation energy with CuBr catalysis is smaller than the activation energy with CuI catalysis. CuBr, therefore, promotes the higher catalytic activity, which is in good agreement with experimental results.