Magnetically nano core-shell Fe3O4@Cu(OH)x: a highly efficient and reusable catalyst for rapid and green reduction of nitro compounds

Magnetically separable nano core-shell Fe3O4@Cu(OH)(x) with 22 % Cu content was prepared by the addition of sodium hydroxide to a mixture of CuCl2 center dot 2H(2)O and nano Fe3O4 in water. Characterization of the impregnated copper hydroxide was carried out by X-ray fluorescence (XRF), X-ray diffraction (XRD) atomic absorption spectroscopy (AAS), scanning electron microscopy (SEM), value stream mapping (VSM) and Brunauer-Emmett-Teller (BET) analysis. The core-shell nanocatalyst exhibited the excellent catalytic activity toward reduction of various nitro compounds to the corresponding amines with NaBH4. All reactions were carried out in H2O (55-60 A degrees C) within 3-15 min to afford amines in high to excellent yields. Reusability of core-shell Cu(OH)(x) catalyst was examined 9 times without significant loss of its catalytic activity.