Synthesis of dipentaerythritol (DPE) by dehydration of pentaerythritol (PE) has been studied using heteropoly compounds and various solid acids. Heteropoly compounds such as H3PW12O40, H4SiW12O40 and their supported catalysts were found to be effective. The addition of water in the reactant suppressed the consecutive reaction of dipentaerythritol with pentaerythritol over H3PW12O40. Under atmospheric pressure at 463 K, silica-supported H3PW12O40 gave 30% yield, while zeolites (H-beta, H-mordenite, and H-Y) and SiO2-Al2O3 were inactive. Turnover number reached 31 over 20 wt.% H3PW12O40/SiO2, indicating that this reaction took place catalytically on it. (C) 2003 Elsevier B.V. All rights reserved.