There is a growing interest to magnetic nanoparticles area, due to their technological applications such as ferrofluids, magnetic drug delivery and high density information storage. Among them, great attention has focused on the preparation and characterization of superparamagnetic metal oxide nanoparticles of spinel ferrites, MFe2O4 (M = Cu, Co, Mg, Mn, Ni, etc.). In this series, the spinel ferrite nanoparticles have special importance. Recent reports show that the magnetic nanoparticles are efficient catalysts and can facilitate their separation from the reaction medium by applying a permanent magnet. The conjugate addition of amines to electron deficient alkenes is an important and widely used transformation in organic synthesis owing to the importance of the resultant β-amino ketones, esters or amides. These β-amino carbonyl compounds are versatile synthetic intermediates for the synthesis of a variety of biologically important natural products, antibiotics and are useful in fine chemicals and pharmaceuticals synthesis. In this research work, we report the application of copper ferrite nanoparticles, CuFe2O4, in heterogeneous systems for aza-Michael addition of amines to α,β-unsaturated carbonyl compounds. Due to their prevalence and wide utility in organic synthesis, the development of novel synthetic methods leading to β-amino ketones is important. Several α,β-unsaturated carbonyl compounds such as chalcone, p-methyl chalcone and p-chloro chalcone as Michael acceptors were subjected to this reaction with CuFe2O4 as catalysts and aniline, p-bromo aniline, p-methyl aniline as the nucleophilic amine. These reactions take place in mild conditions with high yield and products were characterized by spectroscopy methods. Finally, it is remarkable that the use of easily accessible and recyclable copper ferrite nanoparticles makes this procedure simple and green aspect by avoiding toxic or corrosive catalysts. The use of magnetic nanoparticles as catalyst provides selective methods for the synthesis of various organic compounds which are being investigated.

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