Magnetically recoverable nano-sized mesoporous solid acid: effective catalysts for the synthesis of 1-amidoalkyl-2-naphthols

Magnetic mesoporous solid acid, SO3H-MCM-41@NiFe2O4, was prepared and characterized by transmission electron microscopy, X-ray diffraction, N2 adsorption–desorption, and hysteresis loop. Under optimized reaction conditions, three-component condensation of aromatic aldehydes with 2-naphthol and benzamides gave corresponding 1-amidoalkyl-2-naphthols in satisfactory to excellent yields. Catalyst could be recovered by magnetic separation and reused for new runs without significant decrease in activity.