Sulfonic acid was anchored on the surface of silica-coated cobalt ferrite core to obtain a new magnetically separable catalyst. The resultant composite was characterized by various techniques, including FT-IR, X-ray diffraction, FESEM, energy-dispersive X-ray, TEM, TGA, and vibrating sample magnetometer. The immobilized sulfonic acid was shown to be an efficient heterogeneous catalyst for the synthesis