A facile approach to the synthesis of structurally diverse 6,8a-dihydropyrido[2,3-d]pyrimidine derivatives via a three-component domino reaction

A concise and efficient approach to the synthesis of structurally diverse 6,8a-dihydropyrido[2,3-d]pyrimidine derivatives has been accomplished by a three-component reaction involving sulfonyl acetonitrile, an aromatic aldehyde, and 6-aminouracil. The method involves the domino Knoevenagel condensation/Michael addition/cyclization cascade in the presence of triethylamine in refluxing ethanol.