Sulfonated Core-Shell Magnetic Nanoparticle (Fe₃O₄@SiO₂@PrSO₃H) as a Highly Active and Durable Protonic Acid Catalyst; Synthesis of Coumarin Derivatives through Pechmann Reaction.

Esfahani, Farhad Kabiri; Zareyee, Daryoush; Yousefi, Reza

Sulfonic acid supported silica coated magnetic nanoparticles (Fe3O4@SiO2@PrSO3H), was prepared by using low cost precursors and a facile immobilization technique. The final catalyst, which was characterized by XRD, FT-IR, vibrating sample magnetometer (VSM), TEM, and TGA techniques, was found to be an efficient and environmentally benign solid acid for the Pechmann condensation of substituted phenols with ethyl acetoacetate leading to the formation of coumarin derivatives. After the reaction, the catalyst could be effortlessly separated by external magnet and reused for 22 consecutive runs, without any significant loss in catalytic efficiency. The catalytic system presented offers a reusable strategy for the efficient synthesis of coumarin, simplicity in operation, and a green reaction profile by avoiding toxic conventional catalysts and solvents.

NANOSTRUCTURED materials synthesis; MAGNETIC nanoparticles; COUMARIN derivatives; COUMARINS; HETEROCYCLIC compounds synthesis; SILICON oxide; METAL coating; SULFONIC acids; X-ray diffraction; CATALYTIC activity

ChemCatChem, 2014, Vol 6, Issue 12, p3333

1867-3880

Academic Journal

10.1002/cctc.201402547