Triethylaminium-N-sulfonic acid tetrachloroaluminate (TSAT) as a new ionic liquid was synthesized and characterized by its FT-IR, 1H, 13C NMR and mass spectra as well as TG and DTG diagrams. This ionic liquid was employed as a catalyst for the synthesis of [1,2,4]triazolo[1,5-a]pyrimidines-6-carboxamides via one-pot three-component reaction of aromatic aldehydes, acetoacetanilide and 3-amino-1,2,4-triazole under solvent-free conditions at 60 °C .The salient features of the present protocol are mild reaction condition, easy isolation of products and clean reaction profiles.