MCM-41 was found to be the most effective heterogeneous catalyst for the synthesis of calix(4)pyrrole. Various metal ion substituted MCM-41 samples were synthesized and were used to improve the yields of calix(4)pyrrole. Co-MCM-41 was found to give maximum yields. The effects of varying Si/Al ratio in MCM-41, molar ratio of various reactants, and the role of solvent towards this macrocyclization reaction have been studied. (c) 2005 Elsevier B.V. All rights reserved.