eng Science and Education Publishing World Journal of Chemical Education 2375-1657 2025-02-17 13 1 17 18 10.12691/wjce-13-1-3 WJCE20251313 article Sujata Sengupta 1 Sharda Mahilkar Sonkar sharda.sonkar@mirandahouse.ac.in 1 Anand Sonkar 2 Department of Chemistry, Miranda House, University of Delhi, Delhi, India Department of Botany, Hansraj College, University of Delhi, Delhi, India Qualitative organic analysis is a key element of chemistry students' laboratory training worldwide, equipping them with essential skills for careers in research and development. However, traditional methods used for such analysis often do not align with the principles of green chemistry. As part of our ongoing efforts to incorporate sustainable practices into undergraduate and postgraduate chemistry labs, we report a green methodology for preparing 3,5-dinitrobenzoates of alcohol part of ester, used in the characterization of unknown esters. In the present method, the ester is directly treated with the 3,5-dinitrobenzoic acid in presence of a few drops of conc. sulphuric acid in a microwave oven at ~70°C for 5 minutes. https://pubs.sciepub.com/wjce/13/1/3/wjce-13-1-3.pdf qualitative organic analysis microwave oven green chemistry 3 5-dinitro benzoates