University of Kashan Journal of Nanostructures 2251-7871 9 2 2019 04 01 Kaolin-SO3H nanoparticles: A new efficient and reusable catalyst for synthesis of 2-substituted benzimidazoles at room temperature 219 229 76688 10.22052/JNS.2019.02.004 EN Abdolhamid Bamoniri Department of Organic Chemistry, Faculty of Chemistry, University of Kashan, Kashan, Iran Bi Bi Fatemeh Mirjalili Department of Chemistry, College of Science, Yazd University, Yazd, Iran Nahid Yaghmaeiyan-Mahabadi Department of Organic Chemistry, Faculty of Chemistry, University of Kashan, Kashan, Iran Journal Article 2017 06 28 Kaolinite clay found its application in medicine, in toothpaste, in cosmetic and as a food additive. Recently, a specially formulated spray is used in fruit and vegetable production to repel the insects and prevent sunburn. Kaolin-SO3H nanoparticles were prepared via reaction of kaolin and chlorosulfonic acid and characterized by FT-IR, XRD, FESEM, TEM, XRF, EDS, BET and TGA. 2-Substituted benzimidazoles have been used as selective neuro-peptides YY, receptor antagonists, antitumor, antivirus, antimicrobial, antioxidant, antiparasitic, antihelmintics, antiproliferative, anti-HIV, anticonvulsant, anti-inflammatory, antihypertensive, antineoplastic, analgesicand antitrichinellosis, topoisomerase IV inhibitors, potent inhibitors of TiE-2 and VEGFER-2 tyrosine kinase receptor, and 5-HT3 antagonists. 2-Substituted benzimidazoles are prepared via condensation of o-phenylenediamines and aldehydes. In this article, we have used Kaolin-SO3H nanoparticles for the synthesis of 2-substituted benzimidazoles under mild reaction conditions. The structure of products were identified by FT-IR, 1H-NMR and 13C-NMR. This method has the advantages of high yields, short reaction times and easy work-up. https://jns.kashanu.ac.ir/article_76688_eb6e4e7d1a873ce1df52f867e2b6e9ff.pdf