In this work, agro‐waste stuff was employed as a natural source catalyst for the synthesis of 2‐amino‐4H‐chromene as green protocol. The synthesis was carried out in three component one‐pot condensation of aldehyde, malononitrile and naphthol/resorcinol in the presence of Water Extract of Lemon Fruit Shell Ash (WELFSA) as a greener catalyst. Different synthetic methods were examined for the synthesis of 2‐amino‐4H‐chromene under WELFSA extract, and found microwave assisted reaction gave faster reaction rate with the separation of solid in high yield. The isolated products were checked for its purity by TLC. The final product was characterized by FT‐IR, 1H‐, 13C‐NMR and mass spectrometry.

Agro-waste stuff ash extracted solution have been emerging in recent practicing green reaction catalysis in organic synthesis. The derived media have been demonstrated in reactions like Sonogashira, Dakin, Henry, Suzuki-Miyaura, amide bond formation. Traditionally, these reactions were performed in organic solvents and used expensive catalysts with elevated temperature. These catalytic media showed distinct properties during reaction course such as, in situ base, homogeneous catalysts and reducing agent. The present work reviewed green protocol synthesis of 2-amino-4H-chromene derivatives employing reaction of substituted benzaldehyde, malononitrile and α/βnaphthol or resorcinol; three component reaction catalyzed in the presence of water extract of banana peel ash (WEB) extraction under microwave and grindstone methods is described. The reaction found eco-friendly, simple reaction condition with easy separation of final product in pure form. The final product was characterized for its homogeneity using spectroscopic techniques. Some of the selected chromene derivatives (3b, 3d, 3g) prepared in this method is tested for its in vitro antimicrobial studies. The bioassay revealed that products 3b and 3d showed positive response and comparable antimicrobial activity with the reference compounds.

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