An ecologically friendly, low-cost, and biogenic preparation of iron oxide nanoparticles (Fe3O4 NPs) via a green approach utilizing waste biomass material is reported. The catalyst efficiency for Friedel-Crafts acylation to access functionalized anisole under solvent-free conditions and synthesis of quinoxaline derivatives utilizing water as a green solvent is described. The Fe3O4 NPs were synthesized biogenically using an aqueous extract of areca nut husk (ANH) and subsequently confirmed by various standard spectroscopic and microscopic characterization techniques. FESEM analysis displayed a spherical, agglomerated porous morphology, while the XRD analysis displayed a crystal size of 2.31 nm. TG-DT analysis revealed the stability of the Fe3O4 NPs to be good up to 450 °C, and XPS analysis indicated Fe2+ and Fe3+ oxidation states of the catalyst. A series of anisole and quinoxaline derivatives were prepared in moderate to high yields using the catalyst, and catalyst recyclability, mechanistic elucidation, and gram-scale synthesis are described herein. Additionally, the gas sensing proficiency of Fe3O4 NPs was examined toward oxidizing as well as reducing gases, establishing their potential for value-added applications.
Hota et al. (Wed,) studied this question.