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A novel heterogeneous nanocatalyst was fabricated by depositing copper iodide and Fe3O4 nanoparticles on imidazolium-based ionic liquid-grafted cellulose and successfully characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, vibrating sample magnetometry and flame atomic absorption spectrometry. It was employed to catalyse the reaction of terminal acetylenes with sulfonyl azides to afford highly reactive sulfonyl ketenimine intermediates which were subsequently trapped by secondary amines to give N-sulfonylamidines and N-sulfonylacrylamidines under solvent-free conditions at room temperature. Good to excellent yields, very short reaction times, eco-friendly processing, easy separation and reusability without significant loss of catalytic activity were found to be the notable features of this synthetic protocol.

Palladium-catalyzed cross-coupling reactions of 2,6-diaryl-3,5-dibromo-4-pyrones with imidazole and benzimidazole in the presence of N,N′-dibutylbenzimidazol-2-ylidene as ligand resulted in the formation of the monosubstituted C- and N-arylated products. Kojic acid was also treated with some aryl halides at the same conditions, to afford C-6 arylated derivatives.

A novel, rapid method is presented for the synthesis of alkylaminonaphthols using bismuth trichloride as catalyst under neat conditions.

The synthesized compounds are tested for their cytotoxic activity against LS180, MCF-7, and HL-60 cell lines.

The procedures allow the access to the biologically important ring system: BiCl3-catalyzed three-component coupling of (het)aromatic aldehydes, 2-aminopyridines, and isocyanides renders possible the synthesis of 3-aminoimidazopyridine derivatives.

A series of mono- and bis-benzimidazolium and imidazolium salts of 4-pyrone derivatives has been synthe- sized in good yields, by various quaternization reactions of halomethyl derivatives of 4H-pyran-4-ones. These salts can be used as novel precursors of functionalized N-heterocyclic carbenes and some of them as novel ionic liquids.

An efficient green chemistry method has been developed for the synthesis of 1-amidoalkyl-2-naphthol derivatives via a one-pot three-component condensation of 2-naphthol, aldehydes and amide in the presence of boric acid as a mild catalyst.

A variety of new symmetrically and unsymmetrically substituted title dihydropyridines (V) and (IV), resp., are synthesized via modified Hantzsch reactions and evaluated for their calcium channel blocking activity.

Title compounds (VII) and (IX) are synthesized starting by Baylis—Hillman reaction of formylpyrones (I) under convenient conditions.

The new β-chloroacrolein with a pyranone moiety (III) is subjected to a three-component Mannich-type reaction with anilines (IV), cyclic ketones (V), and acyclic ketones in the presence of a zirconium catalyst.

2,6-Bis(1H-indole-6-yl)-4H-pyran-4-one was synthesized via Leimgruber–Batcho methodology starting from 2,6-bis(4-methyl-3-nitrophenyl)-4H-pyran-4-one . Enamine intermediate in this reaction, , reacts with aroyl chlorides in the presence of 1,4-diazabicyclo[2.2.2]octane in dioxane to give the substituted enamines . Enamines undergo reductive cyclization with Fe/AcOH to the corresponding 3-aroylindoles 10a ,10b. J. Heterocyclic Chem., 46, 273 (2009).