Polymethylhydrosiloxane derived palladium nanoparticles for chemo- and regioselective hydrogenation of aliphatic and aromatic nitro compounds in water

Abstract

Chemo- and regioselective hydrogenation of a wide range of aliphatic, unsaturated, aromatic and heteroaromatic nitro compounds into their corresponding amines has been achieved with highly efficient polysiloxane-stabilised “Pd” nanoparticles on NAP-magnesium oxide supports using an environmentally friendly hydrogenating agent, polymethylhydrosiloxane [PMHS] in water. Highly stable and active Pd nanoparticles were prepared by the reduction of NAP-Mg-PdCl₄ with PMHS, which serves as a reducing agent as well as a capping agent. The well-dispersed palladium nanoparticles on NAP-MgO catalysts also exhibit excellent regioselectivity in the hydrogenation of dinitrobenzenes to the corresponding nitroanilines. The catalyst has high durability against sintering during the hydrogenation reaction and can be reused with no loss in its activity.