Hidròlisi de nitrils amb catalitzadors de ruteni: bestudi del mecanisme de reacció

Abstract

Hydrolysis of different types of nitriles, such as acrylonitrile or benzonitrile, to selectively obtain the corresponding amides, has been successfully done using ruthenium catalysts such as [RuCl2(pypz-H)(DMSO)2], which eliminates the need for a base. In order to direct further optimization of the catalyst, the mechanism by which this reaction occurs has been studied. Based on the mechanisms proposed by Solomon et al. on the study of the nitrile hydratase, several possible routes of the ruthenium catalyst have been proposed. The viability of all of them have been studied and evaluated by computational calculations, determining the internal energy and the free energy in the aqueous phase. There have also been relevant calculations to determine which ligand dissociated to allow nitrile coordination, and if this varies depending on the route. In short, the main route of this reaction has been determined, as well as three possible secondary routes that could at least be competitive to the main one. At the same time, other species potentially present in the potential energy surface have been studied in order to determine their capability of decreasing the overall reaction rate and yield. These new insights may lead to future improvements of ruthenium catalysts for the nitriles hydrolysis