Fast and convenient synthesis of new symmetric pyrano[2,3-d:6,5-d']dipyrimidinones by an organocatalyzed annulation reaction

Abstract

A fast and facile one-pot procedure for the preparation of symmetric 5-Aryloyl-1,9-dimethyl- 5,9-dihydro-2H-pyrano[2,3-d:6,5-d']dipyrimidine-2,4,6,8(1H,3H,7H)-tetraone derivatives by two-component reaction of N-methylbarbituric acid and arylglyoxalmonohydrates catalyzed by DABCO in ethanol at 50 ºC is described. This protocol has the advantages of environmental friendless, very simple operation, high regio- and chemoselectivity and moderate to excellent yields.