In the last half-century, quinoline derivatives have been extensively investigated due to their biological and pharmaceutical activities. It has been reported that quinoline derivatives widely served as antagonists, analgesic agents, 5HT3, NK-3 receptors, and structural subunits of natural products. Quinoline-4-carboxylic acids are one of the most important series of quinoline derivatives because they have a variety of medicinal effects and are applied as active components in industrial antioxidants. 1-3 Herein, we designed a novel and reusable nanomagnetic catalyst, which was synthesized and its catalytic application was examined at the synthesis of benzo-[h]quinoline-4-carboxylic acid derivatives via a three-component reaction (Figuer 1). Resulting experimental data suggest that the final step of the plausible mechanism proceed via a cooperative vinylogous anomeric based oxidation mechanism. The presented catalyst shows excellent potential of recycling and reusing at the described multicomponent reaction.
