CuI incorporated cobalt ferrite nanoparticle as magnetically separable catalyst for oxidative amidation reaction
A Cu-incorporated magnetic nanocatalyst (CoFe2O4@SiO2-SH-CuI) has been developed by immobilizing CuI on the modified surface of CoFe2O4 magnetic nanoparticle. The surface of the silica coated cobalt ferrite magenetic core was first treated with 3-mercaptopropyl triethoxy silane to produce the thiol functinalized nanoparticle CoFe2O4@SiO2-SH. Further treatment of the nanoparticle with CuI produced the desired magnetic nanocatalyst. The versatility of the catalyst has been demonstrated for the synthesis of N-(pyridin-2-yl) benzamide via oxidative amidation of aryl aldehydes with 2-amino pyridine in presence of an oxidant. The reaction was carred out in DMSO in 80 ⁰C using TBHP (70% aqueous) in presence of 20 wt% of the catalyst. Notably, the catalyst could be separated from reaction mixture in the presence of an external magnetic field. During the study, a new compound N-(pyridin-2-yl)anthracene-2-carboxamide has been synthesized and its turn on fluorescence sensing property towards various metal ions have been studied. Fluorescence experiments and theoretial study indicated that the newly synthesized carboxamide molecule can be used for fluorescence sensing detection of Hg2+ ion in aqueous solution.