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用量子化学方法研究了丙酸与苯胺缩合反应机理。并用ＭＮＤＯ方法进行了优化计算，得到了丙酸苯胺盐及其质子化的丙酸苯胺盐的平衡几何构型、净电荷和酸催化下的亲核加成及消除反应的势能曲线。由过渡态能量与基态能量之差求得这两个反应的活化能分别为３２．４８ｋＪ／ｍｏｌ和５８１．３２ｋＪ／ｍｏｌ．计算结果表明，消除反应是速度控制步骤。由计算结果发现，质子化后丙酸羰基碳原子上的净电荷增大，前线分子轨道的能级差比未质子化的能级差小得多，即质子化后前线分子轨道间更易相互作用。这表明酸催化大大增强了反应活性，酸催化的本质在理论上得以体现
The mechanism of condensation reaction between propionic acid and aniline was studied by quantum chemistry method. The equilibrium geometry of aniline salt of propionate and its protonated aniline propionate was obtained. The potential charge curves of nucleophilic addition and elimination reaction under net charge and acid catalysis were obtained. The activation energies of these two reactions are calculated from the difference between the energy of the transition state and the energy of the ground state, which are respectively 32.48 kJ / mol and 581.32 kJ / mol. The calculation results show that the elimination reaction is the speed control step. The calculated results show that the net charge on the carbonyl carbon atom of propionate increases after protonation, and the energy difference of the front molecular orbitals is much smaller than that of the unprotonated ones, that is, the protonated frontier molecular orbitals more easily interact with each other. This shows that acid catalysis greatly enhances the reactivity, the nature of acid catalysis in theory to be reflected