Fe 3 O 4 magnetic nanoparticles coated with a copolymer: a novel reusable catalyst for one-pot three-component synthesis of 2-amino-4 H -chromene

摘要: In this paper, an efficient method for the synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-chromene derivatives is described. The uses Fe3O4 magnetic nanoparticles coated with poly (e-caprolactone)/poly (ethylene glycol)/poly (e-caprolactone) (MNPs-Fe3O4/PCL–PEG–PCL) as a biodegradable and green catalyst under solvent-free conditions. was prepared from PCL–PEG–PCL copolymer MNPs-Fe3O4 characterized by FT-IR, X-ray diffraction SEM spectroscopy. Most aromatic aldehydes bearing electron-withdrawing or electron donating groups reacted successfully malononitrile dimedone conditions at 80 °C. corresponding chromenes were isolated in good to excellent yields structures them confirmed 1H NMR IR could be recovered using external magnet without considerable loss its catalytic activity. Moreover, some advantages are simplicity procedure, easy separation catalyst, high yields, efficiency, stability non-toxicity short reaction times, environmentally benign