A efficient, regioselective and solvent free synthesis of 5,9-dihydropyrimido[4,5-e][1,2,4]triazolo[1,5-a]pyrimidine-6,8(4H,7H)-diones derivatives in presence nanocatalyst sulfuric acid grafted with silica-3-aminotriazol

Abstract

In this research, SO3H-functionalized Silica grafted 3-amino triazol has been prepared and identified through FT-IR, XRD, EDX, Fe-SEM, and TGA spectra. 3-chloropropyltriethoxysilane was first reacted with silica nanoparticles and then treated with 3-amino-1H-1,2,4-triazoles and grafted finally with chlorosulfonic acid to prepare SiO2@(CH2)3-AT/SO3H (SNPS-AT/SO3H). Afterward, the catalytic efficiency has been investigated as a homogeneous and recyclable catalyst for the solvent-free synthesis of 5,9-dihydropyrimido[4,5-e][1,2,4]triazolo[1,5-a]pyrimidine-6,8(4H,7H)-diones by the one-pot multi-component reaction of aromatic aldehydes with 3-amino-1H-1,2,4-triazoles and 1,3-dimethyl barbituric acid under thermal (100 °C) conditions.