Sulfamic-Acid-Functionalized Fe_(3-x)TixO4 Nanoparticles as Novel Magnetic Catalyst for the Synthesis of Hexahydroquinolines under Solvent-Free Condition

摘要

Sulfamic acid-functionalized Fe_(3-x)TixO4 nanoparticles ( Fe_(3-x)TixO4-SO3H NPs) were fabricated as novel acidic magnetic nanocatalyst by the reaction of Fe_(3-x)TixO4 magnetic nanoparticles (MNPs) with 3-chloropropyltrimethoxysilyl urea (TMSPU) followed by functionalization with chlorosulfonic acid.The structure of the synthesized nanocatalyst was studied using different methods including,Fourier-transform infrared (FT-IR),field-emission scanning electron microscopy (FE-SEM),transmission electron microscopy (TEM),powder X-ray diffraction (XRD),energy-dispersive X-ray spectroscopy (EDX),thermogravimetric analysis (TGA),vibrating sample magnetometer (VSM),and dynamic light scattering (DLS).The potential catalytic ability of the synthesized MNPs was studied in one-pot fourcomponent condensation reaction between aromatic aldehydes,dimedone,alkyl acetoacetates and ammonium acetate in order to synthesis of hexahydroquinoline derivatives.It was witnessed that the reactions proceeded smoothly under solvent-free condition with high yields of corresponding hexahydroquinolines.