Enaminones as building blocks in heterocyclic synthesis: A new one pot synthesis of polyfunctional substituted pyridines

Enaminones react with a variety of active methyl and methylene reagents in presence of ammonium acetate to yield functionally substituted pyridines in good yields. The reaction proceeded via initial Michael addition across th e double bond followed by cyclization. The reaction of enaminone with aroma tic aldehyde in acetic acid/ammonium acetate afforded the dihydropyridine t hat was oxidized to the corresponding pyridine.