OICC Press Iranian Journal of Catalysis 2345-4865 6 3 2024 02 03 Application of SBA-Pr-SO3H as a solid acid nanoreactor in the Biginelli reaction EN Zohreh Kheilkordi Department of Chemistry, Alzahra University, Vanak Square, P.O. Box 1993893973, Tehran, Iran. Ghodsi Mohammadi Ziarani Department of Chemistry, Alzahra University, Vanak Square, P.O. Box 1993893973, Tehran, Iran. 0000-0001-5177-7889 Parisa Gholamzadeh Department of Chemistry, Alzahra University, Vanak Square, Tehran, Iran, P.O. Box 1993893973. Alireza Badiei School of Chemistry, College of Science, University of Tehran, Tehran, Iran. 0000-0002-6985-7497 Journal Article 2024 02 03 Sulfonic acid functionalized nanoporous silica (SBA-Pr-SO3H) with a pore size of 6 nm catalyzed three component coupling of aromatic aldehydes, urea and ethyl acetoacetate to afford the corresponding dihydropyrimidinones under solvent free condition. This new protocol for Biginelli reaction has important advantages such as green synthesis, short reaction time, easy isolation and high yields of products and reusability of the catalyst. SBA-Pr-SO3H was proved to be an efficient heterogeneous nanoporous solid acid catalyst which could be easily handled and removed from the reaction mixture by simple filtration and can be recovered and reused for several times without any loss of activity.