Polypyrrole (PPY)/Fe 3 O 4 /CNT has been synthesized and characterized by FT-IR, TEM and SEM techniques and its catalytic activity has been evaluated in the synthesis of several series of pyran derivatives. Tetrahydrobenzo[b]pyranes, 4Hpyran-3-carboxylates, 4H,5H-pyrano[3,2-c]chromenes and dihydropyrano[2,3-c] pyrazoles have been successfully prepared from one-pot three-component condensation of aldehyde, malononitrile and active methylene-containing compounds (dimedone /ethyl acetoacetate/4-hydroxycoumarin/3-methyl-2pyrazoline-5-one) using PPY/Fe 3 O 4 /CNT as a new and reusable heterogeneouscatalyst. The present method offer several advantages such as; high yields of products, short reaction times, easy work-up procedure and easy separation of the catalyst from the reaction mixture due to its magnetic character. Furthermore, chemoselective synthesis of bis-benzo[b]pyran from terephthalaldehyde can be achieved by this method.

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