Activated nitriles in heterocyclic synthesis: Novel Synthesis of Pyrimidine and of Pyridine Derivatives

α-Cyanochalcone reacted with thiourea and guanidine to yield the corresponding pyrimidine derivatives 2 and 4 . On the other hand, urea reacted with the same reagent under the same experimental conditions to yield the known urea derivatives 3 . A new synthesis of polyfunction pyridine via reaction of 1a with malononitrile in presence of aniline could be developed. Similar to the behaviour of 1a , Compounds 1b , c reacted with malononitrile in presence of aniline to yield compounds 8 and 9 . In contrast to the behaviour of compounds 1a – c , 1d reacted with malononitrile to yield the malononitrile derivatives 10 or 11 based on the reaction conditions. Mechanisms to account for formation of the reaction products were suggested.