We demonstrate herein the modification of
magnetic nanoparticles and their use as a magnetic nanocatalyst
in direct coupling reactions of aryl halides with
terminal alkynes. Magnetite particles were prepared by
simple co-precipitation method in aqueous medium, and
then Fe3O4@ SiO2 nanosphere was synthesized by using
nano-Fe3O4 as the core, TEOS as the silica source and
PVA as the surfactant. Fe3O4@SiO2 was coated with
polymeric N-heterocyclic carbene/Pd. The samples were
characterized by X-ray diffraction, Fourier transform
infrared spectroscopy, transmission electron microscopy,
field emission scanning electron microscopy, dynamic light
scattering, thermogravimetric analysis, vibration sample
magnetometer and N2 adsorption–desorption isotherm
analysis. Poly (N-vinyl imidazole) functionalized
Fe3O4@SiO2 nanoparticle was found to be an efficient
nanocatalyst in Sonogashira–Hagihara cross-coupling
reactions. The nanocatalyst can be easily recovered by a
magnetic field and reused for six runs without appreciable
loss of its catalytic activity.
