This work describes a new method for a one-pot multicomponent condensation of a variety of aldehydes with dimedone and malononitrile in water, providing a simple and effectual procedure for preparing 4H-chromene under reflux conditions with magnetic nanoparticles supported on functionalized 7-aminonaphthalene-1,3-disulfonic acid-functionalized silica as catalyst. ( Fe3O4@SiO2@Propyl–ANDSA) has been investigated as a novel catalyst in this reaction. This protocol is novel in (1) avoiding toxic solvents (2) introducing a catalyst with ideal features such as chemical stability, low toxicity, cost-effectiveness and, most importantly, easy, fast and comfortable separation using an external magnet.
