Deep Eutectic Solvent Based on Choline Chloride/Urea as an Efficient Catalytic System for the One-Pot Synthesis of Highly Functionalized 1,4-Dihydropyridines and Polysubstituted 4H-Chromenes

One-pot four-component synthesis of polyfunctionalized 1,4-dihydropyridine derivatives was developed by a condensation of aldehydes, malononitrile, diethylacetylenedicarboxylate and aniline in the presence of choline chloride/urea as a deep eutectic solvent (DES)at room temperature.Moreover, an efficient method was reported for the synthesis of highly substituted 4H-chromenes through one-pot, three-component reactions of cyclohexane-1,3-dione or dimedone, malononitrile and diethylacetylenedicarboxylate, in the presence of the deep eutectic solvent at 60 °C. This method develops by using an environmentally benign synthetic method along with the use of a costeffective catalyst.