“…We have reported that formylnitroenamines 1 serve as a double electrophilic C3 unit having a nitro group to afford nitrated diazoles, isoxazole, pyrimidines, diazepines, phenols upon treatment with dinucleophiles such as hydrazines, hydroxylamine, guanidines, 1,2-diaminoethanes, and ketones, respectively. Formylnitroenamines 1 are also employed as the C3N1 building blocks, and multiply functionalized nitropyridones and aminonitropyridines are readily prepared under mild conditions . In the present work, new reactivity of 1 , self-condensation leading to hitherto unknown 3,5-dinitro-1,4-dihydropyridines (DNDHPs), upon treatment with a Brønsted acid, is demonstrated.…”