4H-Pyrano[3,2-c]coumarinderivatives are an important class of pharmaceutical compounds that are expensive to prepare by previously reported methods. An efficient and green method was developed to obtain these derivatives using the deep eutectic solvent (DES) zinc chloride/acetamide (n:n = 1:4), which acted as both the catalyst and the solvent for the reaction. An aromatic aldehyde, 4-hydroxycoumarin