Synthesis of 3-unsubstituted 1-alkyl- and 1-aryl-1,4-dihydroquinolin-4-ones from 2-nitroacetophenone via the corresponding 3-amino-1-(2-nitrophenyl)prop-2-en-1-ones and -but-2-en-1-ones by denitrocyclization reaction is described. The nucleophilic cyclization was achieved either by sodium hydride or potassium carbonate in DMF.