Ciprofloxacin-functionalized magnetic silica nanoparticles: as a reusable catalyst for the synthesis of 1H-chromeno[2,3-d]pyrimidine-5-carboxamides and imidazo[1,2-a]pyridines.

In this research, synthesis and characterization of new surface-functionalized magnetic silica nanoparticles are reported. The magnetic silica nanoparticle was synthesized by a silica coating of the magnetite nanoparticles through a sol-gel process, and then, their surface was modified by (3-chloropropyl)triethoxysilane and covalently functionalized by ciprofloxacin. The catalyst activity of prepared functionalized nanoparticle was investigated by isocyanide-based multicomponent reactions for the synthesis of 1H-chromeno[2,3-d]pyrimidine-5-carboxamides and imidazo[1,2-a]pyridines. This catalyst was recycled by magnetic filtration and reprocessed five times without having a significant loss of catalytic activity.