The Cyclization of Ethyl Cyanoacetate and Ketones by Ammonium Acetate

It was found that a cyclized product containing one nitrogen atom could be obtained by the reaction of ethyl cyanoacetate with various ketones in the presence of excessive ammonium acetate. On the basis of this experiment, pyridone derivatives such as 3-cyano-5,6-dihydro-4,6-dialkyl-6-methyl-2-pyridones (I), pyridine derivatives such as 3-cyano-4,6-dialkyl-2-hydroxypyridines (IV), quinoline derivatives such as 4-alkyl-3-cyano-2-hydroxy-5,6,7,8-tetrahydroquinolines (VII), and related heterocyclic compounds were prepared.