Catalytic mechanism of the ruthenium-catalyzed benzonitrile hydrogenation: Insights from quantum mechanics calculations

Abstract

The mechanisms of ruthenium-catalyzed hydrogenation of benzonitriles have been studied using DFT methods. Theory shows that two steps are required to get the final product benzylamine. The energetic analysis demonstrates that the whole reaction process is both kinetically and thermodynamically feasible, in line with the experimental observations. The electronic structure analysis reveals the insights of the ‘H’ transfers during the hydrogenation process. The choice of a proton or hydride transfer depends on the electronic properties of accepting atoms: for a relative electron-rich site, a proton transfer is preferred; whereas for a relative electron-deficient position, a hydride transfer is more favorable.