The immobilized Ni(II)‐thiourea complex on silica‐layered copper ferrite: A novel and reusable nanocatalyst for one‐pot reductive‐acetylation of nitroarenes

In this study, magnetically nanoparticles of CuFe₂O₄@SiO₂@PTMS@Tu@Ni(II) as novel and reusable catalyst were prepared. Synthesis of the Ni (II)‐nanocatalyst was carried out through the complexation of Ni(OAc)₂·4H₂O with the immobilized thiourea on silica‐layered CuFe₂O₄. The prepared nanocomposite system was then characterized using SEM, EDX, XRD, VSM, ICP‐OES, Raman, UV–Vis and FT‐IR analyses. Catalytic activity of the Ni(II)‐CuFe₂O₄ system was investigated towards rapid reduction of aromatic nitro compounds to arylamines with sodium borohydride as well as one‐pot reductive‐acetylation of nitroarenes to acetanilides with NaBH₄/Ac₂O system without the isolation of intermediate arylamines. All reactions were carried out in H₂O within 3–7 min to afford the products arylamines/acetanilides in high to excellent yields. Reusability of the Ni(II)‐nanocatalyst was examined for seven consecutive cycles without the significant loss of the catalytic activity.