Efficient palladium and ruthenium nanocatalysts stabilized by phosphine functionalized ionic liquid for selective hydrogenation

Pd and Ru nanoparticles were synthesized in ionic liquid by using tri(m-sulfonyl)triphenyl phosphine 1-butyl-2,3-dimethyl-imidazolium salt ([BMMIM]3[tppt]) as a stabilizing agent. The well-dispersed Pd and Ru NPs with mean diameters of 2.4 nm and 1.7 nm were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). It was demonstrated that [BMMIM]3[tppt] stabilized Pd and Ru NPs displayed high activity and excellent selectivity in the hydrogenation of functionalized olefins, aromatic nitro compounds and aromatic aldehydes. The Pd and Ru NPs showed better catalytic performance than corresponding commercially available Pd/C and Ru/C catalysts. The present catalytic system could be easily reused at least six times without significant decrease in activity and selectivity.