Photoinduced synthesis of 2-substituted benzimidazoles as effective ophthalmology drugs mediated by new heterojunction Fe3O4/ZnO

Abstract

Benzimidazoles are important medications in ophthalmology primarily due to their ability to treat various eye conditions caused by parasitic infections. Herein, Fe3O4/ZnO is fabricated from the reducing aqueous extract of Petasites hybridus rhizome and introduced as a photocatalyst to synthesize 2-substituted benzimidazoles under illumination of a high-pressure mercury lamp in mild aerobic conditions. The characterization techniques such as SEM, TEM, FT-IR, XPS, UV–VIS, EDS, and XRD are used to identify the photocatalyst. Moreover, various parameters are evaluated on the photocatalytic performance of Fe3O4/ZnO throughout this research. It is realized that the protocol is successful to conduct the condensation reaction across different types of aromatic aldehydes with various substituents. Preliminary mechanistic studies recommended •O2−, OH•, and h+ as reactive oxygen species in the photocatalytic route. Moreover, reusability study confirmed reliable results for the performed photocatalyst for multiple runs, indicating its practical applicability. The successful hot filtration test further validates the stability of the nanophotocatalyst during reactions.