Zinc Sulfamate Catalyzed Efficient Selective Synthesis of Benzimidazole Derivatives under Ambient Conditions

Abstract

Zinc sulfamate (Zn(NH2SO3)2 is a derivative of sulfamic acid (H3NSO3) which possesses “Lewis acidity” and finds well suited in a number of catalytic applications. The present paper describes an efficient, eco-friendly, and clean synthesis of 2-substituted benzimidazole derivatives by reacting diverse o-phenylenediamine with various substituted aromatic aldehydes using a catalytic amount of zinc sulfamate in ethanol at ambient temperature. As a result, 10 mol.% of Zinc sulfamate catalyst showed 92% of respective product yield with 100% conversion using short reaction period in ethanol. Meanwhile, effect of reaction parameters, such as amount of catalyst, different solvents, and reaction temperature on reaction product, was also studied. In addition, in the optimized reaction condition various substituted biological important benzimidazoles derivatives were prepared by using optimized reaction condition in good to efficient yield. In addition, possible reaction mechanism in the presence of zinc sulfamate for the preparation of benzimidazole derivative was sketched and discussed. The present green approach showed significances with faster reaction rate with inexpensive catalyst, which showed excellent and clean yield of benzimidazole in mild reaction condition with easy work-up procedure.

Molecular docking study, and ADMET analysis for the synthesized novel Zn(II) complexes as potential SARS-CoV-2 inhibitors

“…During the last decade, benzimidazole is considered as one of the vital scaffolds and its analogues with adducts of thiazolyl, ester, carboxyl, alkyl, amine groups, and beta-lactam scaffolds, etc. It has drawn the attention of researchers for its wide range of biological activities such as antimicrobial [1-7], anti-cancer [8,9], anti-viral [10], and radiation protector [10], etc, including their strong coordinating abilities as multidentate ligands. The 1 Corresponding Authors e-mail: sampathchinnam@gmail.com inclusion of the various substituents on the benzimidazole ring, tunes its complex's structure, photo physical, photochemical, antimicrobial properties and enhances their efficiency with transition metal complexation due to tunable redox properties [11].…”

Improving the yield of graphene oxide-catalysed N-heterocyclization of amines through fed batch mode

“…N-Heterocyclic compounds were also synthesized using a metal-free catalyst such as dicationic room temperature ionic liquids, 18 fluorophosphoric acid, 19 phosphorofluoridic acid 20 and zinc sulfamate. 21 Exploration of carbonaceous materials has gathered tremendous attention as a metal-free catalyst owing to their superior physicochemical properties of being cost-effective, recyclable, and environmentally friendly. Graphene oxide with excellent dispersibility, high surface area, and a large number of oxygen functionalities, which serve as better anchoring sites, is a potential material for a wide range of organic transformations.…”

Tailored SnO2@MWCNTs efficient and recyclable nano-catalyst for selective synthesis of 4, 5-dihydropyrrolo [1, 2-a] quinoxalines via Pictet–Spengler reaction

“…Among these, the most inspected nano-scale metal oxides is tin dioxide (SnO 2 ), due to its physical and chemical properties which major contributed for different application aspects. As an effort to enhance the electronic property and to improve surface area, SnO 2 can be incorporated on MWCNTs to form a composite material and can be used as a catalyst for organic transformation with the help of improved active sites on the surface [49][50][51][52][53][54]. Such attractive physicochemical properties of SnO 2 @MWCNTs as nano composite prompted us to study its catalytic e ciency in quinoxalines synthesis.…”