The green synthesis of 2-amino-3-cyanopyridines using SrFe12O19 magnetic nanoparticles as efficient catalyst and their application in complexation with Hg2+ ions

In this paper, a family of 2-amino-4,6-diphenylnicotinonitriles are prepared from aromatic aldehydes, acetophenone derivatives, malononitrile, and ammonium acetate via one-pot reaction catalyzed by SrFe12O19 magnetic nanoparticles. SrFe12O19 was an efficient, green, and reusable nanomagnetic heterogeneous catalyst with the average particles’ size of 70 nm which can be recycled and readily and separated from the reaction mixture using an external magnet. Short reaction times and high yields of desired products are the main advantages of the presented procedure. Subsequently, the spectrophotometric method was used to investigation of the complexation process between 2-amino-4,6-diphenylnicotinonitrile as organo-ligand and several metal ions such as Ag+, Cd2+, Co2+, Cr3+, Cu2+, Fe3+, Hg2+, Mn2+, Ni2+, Pb2+, and Zn2+ in CH3CN solution at 25 °C. According to the obtained results, the absorption spectra of organo-ligand in the CH3CN solution only were changed by the addition of Hg2+ ions, which indicates the formation of one absorbing complex compound between organo-ligand and Hg2+ ions. The stoichiometry of the resulting complex was calculated from the computer fitting of the molar absorbance measurements in different mole ratios.