Abstract:

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.

Key words: Reaction mechanism, CuX, Activation energy, Atoms in molecules theory, Nature bond orbital theory