Three Components Ring Transformation Affording Substituted 5-Nitropyridines and 4-Nitroanilines

The ring transformation of 1-methyl-3,5-dinitro-2-pyridone afforded 2-aryl-5-nitropyridines upon treatment with aromatic ketones in the presence of ammonium acetate. In reactions with aliphatic ketones, 2,6- disubstituted 4-nitroanilines could be prepared in addition to corresponding 2,3-disubstituted 5-nitropyridines. In these reactions, dinitropyridone behaved as the synthetic equivalent of unstable nitromalonaldehyde.