(triazinediyl)bis sulfamic acid-functionalized silica-coated magnetite nanoparticles: preparation, characterization and application as an efficient catalyst for synthesis of mono-, bis-, tris- and spiro-perimidines

(triazinediyl)bis sulfamic acid-functionalized silica-coated magnetite nanoparticles have been prepared and applicated as an efficient catalyst for synthesis of mono-, bis-, tris- and spiro-perimidines. the desired products have been synthesized in high purity and good yields. the workup procedure of reaction is simple. the catalyst was easily separated from the reaction mixture with the assistance of an external magnetic field and reused for several runs without deterioration in catalytic activity. the core/shell nanoparticles were characterized by transmission electron microscopy, scanning electron microscope, powder x-ray diffraction, energy dispersive spectrometer, fourier transform infrared spectroscopy and vibrating sample magnetometer.