Carbon-based SILP catalysis for the selective hydrogenation of aldehydes using a well-defined Fe(ii) PNP complex

Abstract

In this work, the supported ionic liquid phase (SILP) method was applied for the immobilization of a newly developed, well-defined hydride Fe(II) PNP pincer complex dissolved in ionic liquid (IL) onto polymer-based spherical activated carbon. This novel SILP catalyst was structurally characterized by electron microscopy, N₂ adsorption–desorption, FTIR, and XPS measurements and was used for the hydrogenation of aldehydes to alcohols. For an optimized pore filling degree, this system showed excellent activity in the chemoselective hydrogenation of different aldehydes and proved to be reusable in at least seven consecutive reaction cycles without any loss in activity. Significantly lower reaction rates were observed, however, compared to a recent study of the same catalyst supported on silica, which was ascribed to the different pore sizes of these two support materials.