NH4I-Catalyzed Selective Synthesis of 2-Substituted Benzimidazoles

Document Type : Original Research Articles

Authors
Usha Rani 1
P. Rama Krishna Veni 2
Vijaya Saradhi 3
D. Chandra Sekhar 4
1 Department of Basic Science and Humanities, Vignan’s Lara Institute of Technology and Science, Vadlamudi, Guntur-522213, Andhra Pradesh, India
2 Department of Applied Sciences & Humanities, Sasi Institute of Technology & Engineering, Tadepalligudem, West Godavari-534101, Andhra Pradesh, India
3 Department of Science and Humanities, KITS Akshar Institute of Technology, Yanamadala, Prathipadu (M), Guntur-522019, Andhra Pradesh, India
4 Department of Engineering Chemistry, SRKR Engineering College, Bhimavaram-534204, Andhra Pradesh, India
10.22059/jsciences.2026.408328.1007980
Abstract
By reacting 1,2-diamines with aromatic, aliphatic, and heteroaromatic nitroalkenes while using ammonium iodide (NH4I) as a green catalyst, a simple and effective synthetic pathway was created. This method is environmentally friendly and allows for the highly regioselective synthesis of 2-substituted benzimidazole derivatives in good to excellent isolated yields (78-94%). A plausible reaction mechanism was proposed. The scope and limitations were further examined.
Keywords
Ammonium iodide (NH4I)
Green catalyst
2-substituted benzimidazoles
1,2-diamines
chemoselectivity
Subjects
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Journal of Sciences, Islamic Republic of Iran
Volume 36, Issue 2
Spring 2025
Pages 143-149