OICC Press Iranian Journal of Catalysis 2345-4865 6 5 2024 02 03 5-sulfosalicylic acid as an efficient organocatalyst for environmentally benign synthesis of 2-substituted benzimidazoles EN Chandrakant Bhenki Department of Chemistry, Rajaram College, Kolhapur 416004, India. 0000-0002-2748-934X Shrikrishna Karhale Department of Chemistry, Rajaram College, Kolhapur 416004, India. 0000-0002-1252-953X Vasant Helavi Department of Chemistry, Rajaram College, Kolhapur 416004, India. Journal Article 2024 02 03 A water soluble, Bronsted acid, 5-sulfosalicylic acid as an efficient organocatalyst was used for the synthesis of physiologically active 2-substituted benzimidazole derivatives from o-phenylenediamine and aromatic aldehydes in ethanol at reflux condition. Cost-effectiveness, use of non-hazardous solvents, metal free and commercially available catalyst, single-step, environmentally friendly green method, high conversions, cleaner reaction profiles and simple experimental and workup procedures are the remarkable features of this method.   A water soluble, Bronsted acid, 5-sulfosalicylic acid as an efficient organocatalyst has been used for the synthesis of physiologically active 2-substituted benzimidazole derivatives from o-phenylenediamine and aromatic aldehydes in ethanol at reflux condition. Cost-effectiveness, use of non-hazardous solvents, metal free and commercially available catalyst, single step, environmentally friendly green method, high conversions, cleaner reaction profiles and simple experimental and workup procedures are the remarkable features of this method.