OICC Press Iranian Journal of Catalysis 2345-4865 12 3 2023 12 24 Nano-SiO2/Taurine as a new natural based catalyst for synthesis of hexahydroquinolines derivative 10.30495/ijc.2022.1959104.1936 EN Saeed Sharifi Sharifabad Department of Chemistry, College of Science, Yazd University, Yazd, P.O. Box 89195-741, Iran Bi Bi Fatemeh Mirjalili Department of Chemistry, College of Science, Yazd University, Yazd, P.O. Box 89195-741, Iran 0000-0002-6588-4041 Abdolhamid Bamoniri Department of Organic Chemistry, Faculty of Chemistry, University of Kashan, Kashan, Iran 0000-0002-8911-2433 Journal Article 2023 12 24 In this research work, Nano-SiO2/Taurine was synthesized and characterized by FT-IR, energy dispersive X-ray analysis (EDX), scanning electron microscopy (SEM), X-ray diffraction patterns (XRD) ,Thermogravimetric analysis (TGA) and MAP analysis. Nano-SiO2/Taurine has considerable benefits such as simple preparation protocol, simple handling, high acidic property, reusability and high stability. Nano-SiO2/Taurine was used as a catalyst for the synthesis of hexahydroquinolines by the reaction of ethyl acetoacetate, dimedone and ammonium acetate with various aldehydes. These reactions were carried out under solvent-free conditions at 85 °C. The present protocol is simple, eco-friendly and efficient. The hexahydroquinolines were produced at high yields and short reaction times.   Highlights Nano-SiO2/Taurine was prepared via reaction between nano silicagel and taurine. Nano-SiO2/Taurine was characterized by FT-IR, energy dispersive X-ray analysis (EDX), X-ray diffraction patterns (XRD), scanning electron microscopy (SEM), Thermogravimetric analysis (TGA) and MAP analysis. Nano-SiO2/Taurine was applied for the synthesis of hexahydroquinoline derivatives by the condensation reaction between ethyl acetoacetate, dimedone, ammonium acetate and various aldehydes. Nano-SiO2/Taurine has considerable benefits such as simple preparation protocol, simple handling, high acidic property, reusability and high stability.