A basic ionic liquid [BMIM]OH could very efficiently catalyze the synthesis of piperido[3',4':5,6]pyrano[2,3-d]pyrimidinone derivatives from pyrano[3,2-c]piperidine analogues and carbonyl compounds. [BMIM]OH acted as a catalyst as well as the reaction medium and could be used for the reactions for five times without any appreciable loss of its catalytic efficiency. The synergic couple of microwave and ionic liquid provided high yields of the product in very short reaction times and allowed easy workup. (C) 2013 Elsevier B.V. All rights reserved.