An efficient, catalyst-free and eco-friendly synthesis of novel pyrano[3,2-e][1,2,4]triazolo[1,5-a]pyrimidines via cyclo-condensation of [1,2,4]triazolo[1,5-a]pyrimidine-5,7(4H,6H)-dione, aromatic aldehydes, and malononitrile has been described using ‘‘On-water” concept. The use of water as a clean media, catalyst-free conditions, excellent functional group acceptance, easier product isolation/purification without column chromatography, short reaction times, and good-to-excellent yields are the remarkable privileges of this protocol. Finally, 1H, 13C NMR, IR, mass spectra, and elemental analyses were conducted to determine the products’ structure.

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