Piperidine and Piperazine Immobilized on Iron Oxide Nanoparticles as Magnetically Recyclable Heterogeneous Catalysts for One-Pot Synthesis of β-Phosphonomalonates

Piperidine and piperazine immobilized on silica-coated gamma-Fe2O3 magnetic nanoparticles were synthesized as new supported bases via the reaction of chloro-functionalized gamma-Fe2O3@SiO2 with piperidine and piperazine, respectively. The resulting bases were employed as magnetically recyclable heterogeneous catalysts for the efficient one-pot three-component synthesis of beta-phosphonomalonates. The catalysts were easily separated from the reaction mixture by using a magnet and recycled for five times without significant loss of the catalytic activity.