Nano-sulfonated Graphene Oxide: A Metal-free Catalyst for the Synthesis of Benzimidazoles and Antimicrobial Activities
J. Environ. Nanotechnol., Volume 15, No 1 (March 2026) pp. 701-715
Abstract
Nano sulfonated graphene oxide (SGO) was synthesized with slight modifications to previously reported methods. An efficient and ecofriendly protocol was developed for the synthesis of benzimidazole derivatives using o-phenylenediamine and D-glucose as substrates, employing a metal-free sulfonated graphene oxide carbocatalyst. A diverse range of benzimidazole derivatives was obtained in moderate to high yields (up to 94%) using a sustainable and readily available C1 source under sonication conditions. The reaction, carried out in ethanol with tertiary-butyl hydroperoxide, provides a general and novel approach for benzimidazole synthesis via a carbonylation pathway. The process is facilitated by a cost-effective and environmentally benign SGO nanocatalyst, enabling the formation of valuable products in excellent yields. The synthesized benzimidazole derivatives exhibited strong antibacterial activity, with inhibition rates of 99% to 100% against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Streptococcus pyogenes.
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