Green protocol for synthesis of MgFe2O4 nanoparticles and study of their activity as an efficient catalyst for the synthesis of chromene and pyran derivatives under ultrasound irradiation

In this study, the MgFe 2 O 4 nanoparticles were synthesized via a green and simple approach. Then an effective procedure to synthesize 2-amino-7-hydroxy-4 H -chromene and tetrahydrobenzo[ b ]pyran derivatives was established through the chemical reaction between different aldehydes, malononitrile and resorcinol (or dimedone) in the presence of MgFe 2 O 4 nanoparticles as a beneficial catalyst in ethanol as solvent under ultrasound irradiation. Moreover, the synthesized MgFe 2 O 4 nanoparticles were easily recovered by an external magnet and reused for four times without significant loss of their catalytic activity. Simple, fast, effective and eco-friendly as well as quick purification method along with high product yields are some of the advantages of the present chemical reaction.