A facile, simple and environmentally friendly Fe₃O₄–cysteine MNP was synthesized without any additive or additional source of linkers. Fe₃O₄–cysteine MNPs were successfully used for the synthesis of β-amino carbonyl and hydroquinoline compounds, which were obtained in excellent yields via multicomponent reactions. Magnetic organocatalysts can be easily recovered by simple magnetic decantation and their catalytic activity remains unaltered after 9 consecutive cycles, making them environmentally friendly and widely applicable due to their efficiency, ease of handling, and cost effectiveness.