1-substituted 3-dimethylaminoprop-2-en-1-ones as building blocks in heterocyclic synthesis: Routes to 6-aryl- and 6-heteroaryl-2H-pyran-2-ones and 6- and 4-arylpyridin-2(1H)-ones

Several new 6-substituted-3-acylamino-2H-pyran-2-ones 6a-j have been prepared from the reaction of enaminones 4a-f with N-acyl- and N-benzoyl-glycines; the enaminones 4a-c react with malononitrile in ethanol solution and in the presence of a base to yield amides 11a-c which are converted into 6-aryl-1,2-dihydro-2-oxypyridine-3-carbonitriles 13a-c on reflux in acetic acid.