Abstract: An environmentally benign protocol for the one-pot,
three-component synthesis of Triazolo[1,2-a]indazole-1,3,8-trione
derivatives by condensation of dimedone, urazole and aromatic
aldehydes catalyzed by HClO4/SiO2 NPS as an ecofriendly catalyst
with high catalytic activity and reusability at 100ºC under solventfree
conditions is reported. The reaction proceeds to completion
within 20-30 min in 77-86% yield.