A simple, green, one-pot synthesis of magnetic-nanoparticle-supported proline without any source of supplemental linkers and application as a highly efficient base catalyst

Abstract

Fe₃O₄–proline MNPs were synthesized without any supplemental linkers, using an eco-friendly and effective procedure. It is readily loaded onto magnetic nanoparticles in a single step and is capable of promoting a range of synthetically useful reactions at ambient conditions. Functionalized chromene derivatives are synthesized via condensation and ring annulations of 2-hydroxynaphthalene-1,4-dione or 4-hydroxycoumarin, aryl aldehyde and malononitrile in the presence of a catalytic amount of Fe₃O₄–proline MNPs at room temperature in excellent yields.