Abstract
One-pot synthesis of 3,4-dihydropyrimidinone/thione and 3,4,5,6-tetrahydropyrimidinone/thione derivatives was successfully performed in high yields through the reaction of aromatic aldehyde, β-dicarbonyl, urea/thiourea using Fe3O4@C@OSO3H nano-catalyst under solvent-free conditions at 80 °C. Fe3O4@C@OSO3H was introduced as an efficient magnetic nano-catalyst in Biginelli condensation with powerful reusability. The great yield of products, fast reaction time, simple work-up procedure, as well as usage of nontoxic, reusable, and easily recoverable catalyst with an external magnet was counted as advantages of the applied process. The magnetic nano-catalyst was removed after reaction completion and reused seven times at the same conditions without significant decay in catalyst activity. The magnetic nano-catalyst was synthesized through a simple and inexpensive two steps method and characterized by FT-IR, EDX, SEM, TEM, DLS, XRD, and VSM techniques.