Efficient Synthesis of 2-amino-4H-chromene Derivatives in the Presence of Piperazine-functionalized Fe<sub>3</sub>O<sub>4</sub>/SiO<sub>2</sub> Magnetic Nanoparticles as a New Heterogeneous Reusable Catalyst Under Solvent-free Conditions

A new piperazine-functionalized Fe3O4/SiO2 magnetite nanoparticle was synthesized through the surface modification of magnetic iron oxide nanoparticles by piperazine. Iron oxide nanoparticles were synthesized by coprecipitation method and the surface modification process was achieved by treating the nanoparticles with tetraethyl orthosilicate (TEOS), chloropropyl trimethoxy silane (CPTS) and piperazine. The developed functionalized iron oxide...