Fe ₃ O ₄ @C@OK, a recyclable superparamagnetic nanocatalyst for facile three-component tandem aldol condensation-thia-Michael sequence of reactions

A novel basic Fe3O4-carbon coated magnetic nanocatalyst (BFCMNPs) was designed and prepared through a facile procedure using inexpensively available reagents. The procedure involved initial preparation of Fe3O4@C followed by its treatment with KOH to afford Fe3O4@C@OK (BFCMNPs). The catalyst was characterized by EDX, TGA, TEM, SEM, FTIR, and XRD methods. The catalytic performance of BFCMNPs was demonstrated in one-pot three-component tandem aldol-thia-Michael combination of acetophenone derivatives with aromatic aldehydes and thiols, where it could act as an environmentally benign, efficient, and easy to recover catalyst to provide the respective 3-(arylthio)propan-1-one adducts in aqueous medium. Use of commercially available starting materials, short reaction times, safe solvent usage, high yields of products, easy procedure, and convenient recovery of the catalyst by applying an external magnetic field and its reuse in seven consecutive runs are the advantages of the present method.