Grafting SnCl4 on inorganic support as a novel solid acid catalyst was used to catalyze the Prins condensation reaction of isobutene with formaldehyde to produce 3-methylbut-3-en-1-ol (MBOH). Three supports of SiO2, SiO2-Al2O3 and gamma-Al2O3 were used to prepare the catalysts, and the structure and acid property of the tin chloride species formed over different supports was investigated. It was found that the SnCl4 grafted on SiO2 exhibited high activity and selectivity at a low reaction temperature of 100 degrees C, with formaldehyde conversion of 55% and MBOH selectivity of 92%. The superior performance of SnClx-SiO2 catalyst was attributed to its low electron density of tin nucleus and strong Lewis acidity. (C) 2011 Elsevier B. V. All rights reserved.