Microwave-assisted Fe3O4 nanoparticles catalyzed synthesis of chromeno[1,6]naphthyridines in aqueous media

Fe3O4 nanocatalyst was prepared by co-precipitation method and characterized by XRD, FT-IR, TEM, VSM and BET analyses. The particles have an average size of 7 nm and possess highly open mesopores, moderate surface area, and uniform morphology with superparamagnetic behavior. Activity of catalyst was probed through the synthesis of chromeno[1,6]naphthyridines in water under microwave irradiation (MW) and it was about 7-fold higher as compared to conventional method. Nanocatalyst plays a dual role of catalyst as well as susceptor, and enhances the overall capacity to absorb MW. Fe3O4 NPs easily recovered by simple magnetic separation and recycled at least 5 times. (C) 2014 Elsevier B.V. All rights reserved.