Molecularly Engineering Defective Basal Planes in Molybdenum Sulfide for the Direct Synthesis of Benzimidazoles by Reductive Coupling of Dinitroarenes with Aldehydes

Abstract

Developing more sustainable catalytic processes for preparing N-heterocyclic compounds in a less costly, compact, and greener manner from cheap and readily available reagents is highly desirable in modern synthetic chemistry. Herein, we report a straightforward synthesis of benzimidazoles by reductive coupling of o -dinitroarenes with aldehydes in the presence of molecular hydrogen. An innovative molecular cluster-based synthetic strategy that employs Mo 3 S 4 complexes as precursors have been used to engineer a sulfur-deficient molybdenum disulfide (MoS 2 )-type material displaying structural defects on both the naturally occurring edge positions and along the typically inactive basal planes. By applying this catalyst, a broad range of functionalized 2-substituted benzimidazoles, including bioactive compounds, can be selectively synthesized by such a direct hydrogenative coupling protocol even in the presence of hydrogenation-sensitive functional groups, such as double and triple carbon–carbon bonds, nitrile and ester groups, and halogens as well as diverse types of heteroarenes.

Enhanced NH3 Sensing Performance of Mo Cluster-MoS2 Nanocomposite Thin Films via the Sulfurization of Mo6 Cluster Iodides Precursor

“…Three Mo 3d 5/2 -3d 3/2 doublet peaks are attributed to the Mo 4+ , Mo 5+ , and Mo 6+ states for MI-250. According to the HRTEM result of MI-250, the Mo 4+ states can be attributed to the MoS 2 layered structure, whereas the Mo 5+ states correspond to the Mo x S y clusters [ 61 , 62 , 63 , 64 ]. Finally, the Mo 6+ doublet peak must be due to MoO x , which is produced from the MI@FTO and bound water.…”

Recent Scenario for the Synthesis of Benzimidazole Moiety(2020–2022)

“…The mechanistic pathway is similar to that mentioned earlier (scheme 23). [26] In 2022, a novel lindqvist type organic-inorganic hybrid catalyst ([Mo 6 0 18 ]@GO-NH 2 ) was synthesised for the preparation of various benzo-fused heterocyclic compounds 24 a. Reaction takes place between 1,2-phenylenediamine( 1 mmol) and ChemistrySelect aromatic aldehydes (1 mmol) in presence of catalyst 10 mg in solvent CH 3 CN (10 mL) for 2 h (scheme 24).…”

Facile Protocol for the Synthesis of Electron-Rich Benzimidazole Derivatives

“…11 More recently, Corma, Sorribes, and coworkers have described the synthesis of benzimidazoles by reaction of o-dinitrobenzene derivatives with aldehydes under catalytic hydrogenation conditions. 12 One example of treatment of an o-dinitrobenzene derivative with sodium dithionite in the presence of an aldehyde to yield a benzimidazole has been reported by Queffelec, Pellegrin and coworkers, 13 but required 10 days of heating the reaction mixture at reflux. Use of sodium dithionite in other reductive cyclizations has also been reported.…”