Mechanism Of Hydrogenation Of N-Heteroaromatic Compounds Using Transition Metal Catalyst

The hydrogenation of2-phenylquinoline catalyzed by [Ru (p-cymene) I2]2has been calculated using B3LYP method. Contrast to the possible reaction pathways, it’s proposed a preferred mechanism for the reaction. All of the transition-states have been searched and the energy barriers are shown.The results suggest that, the hydrogenation of the2-phenylquinoline has two steps in its reaction cycle. The first step is3,4-hydride transfer and the second is1,2-hydride transfer. The activation of H-H bond is important in this reaction.The calculation shows that the3,4-hydride transfer reaction which has an energy barrier of29.32kcal/mol is stepwise with a proton transfer and a hydride transfer. The H-H bond is activated by the reactant and the metal centre of the catalyst. The proton transfer step controls the whole3,4-hydride transfer reaction.The1,2-hydride transfer reaction has an energy barrier of33.84kcal/mol. There are also two steps in this reaction. HI elimination is the first step which is restrained by the polarity of solvent. The H-H bond is activated by the metal centre and the ligand. The second step is hydride transfer which controls the whole1,2hydride transfer reaction. It’s affected by the steric of the substituent group on the position2of the reactant.