Synthesis of heterocyclic compounds. Part 46. The reactions of malonamide and 2-cyanoacetamide with substituted propenones

Abstract

The synthesis of substituted 2-pyridone derivatives from malonamide (1) and 2-cyanoacetamide (2) is reported. Conjugate addition of these compounds to substituted propenones (3) and (4) leads to 6-hydroxy-2-piperidones, which can be dehydrated and aromatized to 2-pyridones (7), (11), and (14). The intermediate 3,4-dihydro derivatives were also obtained and some chemical transformations of the products prepared are also described.