| Catalytic Synthesis of Benzimidazoles Using a Dinuclear Copper(II) Complex with a Tetradentate Nitrogen Ligand |
| کد مقاله : 1043-ICOC |
| نویسندگان |
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مریم بحرانی پور1، هدی حاتمی1، سپیده سمیعی *2، طاهره صداقت2 1دانشگاه شهید چمران اهواز 2عضو هیئت علمی دانشگاه شهید چمران اهواز |
| چکیده مقاله |
| Benzimidazole derivatives constitute an important class of heterocyclic compounds with broad biological and pharmaceutical relevance, prompting continuous interest in developing catalytic systems that operate under mild and environmentally friendly conditions [1]. In this work, a dinuclear copper(II) complex incorporating a bridging tetradentate nitrogen ligand and terminal bromide ligands, formulated as [CuBr(Lp)(DMSO)]₂, was applied as a stable and efficient heterogeneous catalyst for the synthesis of benzimidazoles via the condensation of o-phenylenediamine with various aldehydes. The catalyst remains insoluble in ethanol during the reaction, ensuring complete heterogeneity, operational simplicity, and facile recovery. The dinuclear arrangement, created through bridging by the multidentate N-donor ligand, provides two closely positioned Cu(II) centers capable of cooperatively activating carbonyl substrates at the solid surface, thereby enhancing the cyclocondensation process. All reactions proceeded smoothly at room temperature in ethanol as a green solvent, affording the target benzimidazole derivatives in good to excellent yields within short reaction times. A plausible surface-assisted catalytic mechanism involves adsorption and activation of the aldehyde on the copper centers, followed by nucleophilic attack by o-phenylenediamine, dehydration, and intramolecular cyclization to deliver the heterocyclic product. Collectively, these observations highlight the strong catalytic performance and practical sustainability of this dinuclear copper complex, offering an efficient strategy for the environmentally compatible construction of benzimidazole scaffolds. Scheme 1 illustrates the general reaction pathway. |
| کلیدواژه ها |
| Keywords: Benzimidazoles, Copper II complex, Catalysis, Mild conditions, Ethanol |
| وضعیت: پذیرفته شده |