Ultrasound Assisted Chromatography-Free Synthesis of Triazolo [1,2-a]Indazole-Triones in the Presence of 1,4-Diazabicyclo[2.2.2] Octanium Diacetate as an Environmentally Friendly Green Media

A convenient and high yielding procedure for the synthesis of triazolo[1,2-a]indazole-triones by the condensation reaction between 1,2,4-triazolidine-3,5-dione (urazole), 5,5-dimethylcyclohexane-1,3-dione (dimedone) and aryl aldehydes in the presence of acidic dicationic ionic liquid 1,4-diazabicyclo[2.2.2] octanium diacetate as a highly stable and reusable ecofriendly catalyst under ultrasound irradiation is described. This procedure is simple and successful and offers easy workup, mild condition and excellent yield in a short time. All of the synthesized compounds were characterized by IR, ¹H NMR, ¹³C NMR and elemental analysis.