A green and efficient method for the preparation of 3, 4-dihydropyrimidin-2(1H)-ones using quaternary ammonium- treated clay in water

Document Type : Original Paper


1 Chemistry Department, Mahshahr Branch, Islamic Azad University, Mahshahr 63519, Iran

2 Chemistry Department, Omidieh Branch, Islamic Azad University, Omidieh, Iran


The reactive intermediate generated by the addition of tert-butyl and 1,1,3,3-tetramethyl butyl isocyanide and cyclohexyl isocyanide to dialkyl acetylenedicarboxylate was trapped by 3-hydroxy pyridine to produce highly functionalized 4H-chromenes in fairly good  yields