Nafion-H® catalyzed efficient one-pot synthesis of triazolo[5,1-b]quinazolinones and triazolo[1,5-a]pyrimidines: A green strategy

•Eco-friendly and easy access to triazole fused heterocycles.•Simple, efficient one-pot, three-component condensation reaction.•Use of Nafion-H® as heterogeneous catalyst.•PEG-400 is used as a green solvent system.•Recyclability of the catalyst and the solvent.

Nafion-H® served as an effective and environmental friendly heterogeneous catalyst for the convenient synthesis of a series of [1,2,4]triazolo[5,1-b]quinazolinones and [1,2,4]triazolo[1,5-a]pyrimidines by condensation of 3-amino-1,2,4-triazole as an amine source, different aldehydes and 1,3-dicarbonyl compounds in polyethylene glycol as solvent. The catalyst exhibited excellent recyclability without any significant loss of catalytic activity. This protocol offers several merits like simple work-up, mild conditions, higher yields and recyclability of the catalyst as well as solvent. Moreover, there was no need of product purification via column chromatography as the crude products obtained were very much pure.

Graphical abstractNafion-H® served as an effective and environmental friendly heterogeneous catalyst for the convenient synthesis of [1,2,4]triazolo[5,1-b]quinazolinones and [1,2,4]triazolo[1,5-a]pyrimidines via condensation of 3-amino-1,2,4-triazole, different aldehydes and 1,3-dicarbonyl compounds derivatives in PEG-400 as a reusable solvent.Figure optionsDownload full-size imageDownload high-quality image (105 K)Download as PowerPoint slide