Microwave assisted L‐proline catalyzed one‐pot three–component reaction for the synthesis of 4‐aminoaryl‐2‐phenyl‐2H‐3‐nitrochromene hybrid via Domino Michael‐Henry‐Michael addition reaction

Abstract

AbstractA highly efficient oxidant free, microwave assisted L‐proline catalyzed one pot three‐component reaction has been developed for the synthesis of 4‐aminoaryl‐3‐nitro‐2H‐chromene using o‐hydroxy‐ω‐nitrostyrene, arylaldehyde and arylamine in DMSO solvent. This method involves the stepwise intermolecular Aza Michael addition, nitro‐enolate formation, Henry reaction and intramolecular Oxa‐Michael addition to produce the final product. Various controlled experiments were carried out and intermediates were characterized by ESI‐MS to support the possible reaction path for the formation of desired product. A wide range of substrates were well tolerated and the diverse range of 4‐(phenylamino)‐3‐nitro‐2‐phenyl‐2H‐chromenes have been synthesized in good‐to‐high yields at 80°C within 8–10 min.