Expedite Greener Method Synthesis of Pyrano[2,3-d]Pyrimidine-2,4,7-Triones Accelerated by Ultrasound Irradiation

Abstract

Environmentally benign, facile, and efficient one-pot three-component synthesis of pyrano[2,3-d]pyrimidine-2,4,7-trione derivatives by the reaction of aromatic aldehyde, barbituric acid and Meldrum’s acid employing recently reported agro-waste catalyst WELFSA (Water Extract Lemon Fruit Shell Ash) from our group is described. The reaction found efficient in ultrasound at room temperature and took about 40 min for the reaction to complete. The catalyst has significant features in the present protocol gave high yield, simple reaction condition, non-hazardous, and not required chromatographic purification. The application of the ultrasound in organic synthesis is fulfilling some of the goals of the ‘greener and sustainable chemistry’, as it has some advantages over the traditional thermal methods in terms of reaction rates, yields and purity of the products. All the synthesized derivatives are characterized by FT-IR, 1H and 13C-NMR and mass spectrometry.