Highly efficient synthesis of silica-coated magnetic nanoparticles modified with iminodiacetic acid applied to synthesis of 1,2,3-triazoles

Great efforts have been made to discover new catalysts to facilitate synthesis of organic fine chemicals. In this research, a new silica-coated magnetic nanoparticles functionalized by iminodiacetic acid (Fe3O4@SiO2@IDA) was prepared by the sol-gel method. The structure of nanoparticles was fully characterized by using X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetry analysis. The results revealed that the nanoparticles have spherical morphology and an average size of around 40 nm. The analysis also illustrated that the copper nanoparticles had been successfully loaded on the nitrogen-rich carbon support with a uniform distribution. The inductively coupled plasma analysis showed that about 0.22 mmol g(-1) of Cu was loaded on the Fe3O4@SiO2@IDA support. Application of Fe3O4@SiO2@IDA-Cu as a magnetically recyclable nanocatalyst for synthesis of 1,4-disubstituted-1,2,3-triazole derivatives through an azide-alkyne [3 + 2] cycloaddition reaction was also investigated. Mild reaction conditions, excellent yields (65-90%), environment-friendly synthesis, and easily prepared starting materials are the key features of the present method. The catalyst is easily removed from the reaction media using an external magnetic field and can be reused at least five times without any considerable loss of its catalytic activity.