Core-shell structured Fe3O4@MgO: magnetically recyclable nanocatalyst for one-pot synthesis of polyhydroquinoline derivatives under solvent-free conditions.

Core-shell nanostructured Fe3O4@MgO catalyst was synthesized using a two-fold co-precipitation technique. High-resolution transmission electron microscopy (HR-TEM) images demonstrated that the catalyst had a core-shell framework with spherical morphology. In present study, Fe3O4@MgO is successfully used as an effective, novel, and recoverable nanocatalyst in an easy-to-follow, affordable, environment-friendly, and productive process for the synthesis of polyhydroquinoline derivatives via one-pot four-component Hantzsch condensation reaction. Importantly, magnetically retrievable Fe3O4@MgO nanoparticles provides high catalytic efficiency in solvent-free condition and can be used repeatedly up to six cycles without significant loss of catalytic activity. The study provides a greener route to yield 82-94% of polyhydroquinoline in a short reaction time under ultrasonication. Fe3O4@MgO is a core-shell nanocatalyst that is reliable, affordable, heterogeneous, simple to handle, and recoverable. It can be used repeatedly for up to six cycles without significantly losing catalytic activity. The reaction was found to be effective in giving polyhydroquinoline yield of about 82-94 percent in short reaction times in solvent-free conditions. [ABSTRACT FROM AUTHOR]