Ruthenium-Picolylamine-Incorporated Mixed-Linker MOFs: Highly Active Heterogeneous Catalysts for Olefin and Aldehyde Hydrogenation

The selective hydrogenation of aldehydes and olefins plays a crucial role in the synthesis of various industrial products. Immobilizing noble metal catalysts on solid supports has been pursued to overcome the challenges associated with catalyst separation and recovery. In this study, we explore the use of metal-organic frameworks (MOFs) as supports for the immobilization of molecular ruthenium catalysts in the hydrogenation of olefins and aldehydes. We designed a mixed-linker MOF by incorporating the picolylamine moiety, which is a ligand known for its excellent catalytic activity. The ruthenium catalysts were prepared via a simple metal-ligand coordination process without the need for additional treatments. The resulting catalysts exhibit high catalytic activity and a uniform distribution of ruthenium sites on the MOF crystals. The choice of ruthenium precursor has a significant influence on the catalytic performance, with even lower metal content resulting in higher activity. The catalysts achieve high conversion rates and selectivities in the hydrogenation of various olefins. However, in the hydrogenation of aldehydes, due to the harsher conditions required, the formation of small nanoparticles is observed after the reaction. Overall, our findings highlight the potential of picolylamine-modified MOFs as effective supports for the development of highly active heterogeneous catalysts for selective hydrogenation reactions.