Rust-derived Fe₂O₃ nanoparticles as a green catalyst for the one-pot synthesis of hydrazinyl thiazole derivatives

In the present work, novel one-pot multicomponent reactions of tosylates, aryl aldehydes and thiosemicarbazide are reported for the synthesis of hydrazinyl thiazoles, using Fe2O3 NPs derived from rusted iron as a catalyst. The Fe2O3 NPs were characterized using XRD, SEM, VSM, HR-TEM, EDX and FT-IR techniques. The structures of all of the synthesized hydrazinyl thiazole derivatives were confirmed by 1H NMR, 13C NMR, FT-IR and mass spectrometry. The magnetic Fe2O3 NPs were easily recovered from the reactions using an external magnet, and the catalytic activity of the recycled catalyst was examined over four cycles under optimized reaction conditions; it exhibited minimal loss of yield. To explore potential applications, the synthesized molecules were investigated for their antibacterial, antifungal and antioxidant activities, and they showed promising results. The results were further supported through molecular docking studies.