A novel imidazole ionic liquid (IL)-functionalized [Formula: see text]-[Formula: see text] ([Formula: see text]) is prepared by the functionalization of [Formula: see text] by 1-butyl-3-(3-trimethoxypropyl)-1H-imidazol-3-ium chloride as the IL moiety. The catalyst is characterized by transmission electron microscopy, scanning electron microscope, vibrating sample magnetometer, dynamic light scattering and Fourier transform infrared spectroscopy. [Formula: see text] showed good activity in the synthesis of 6H-chromeno[4,3-b]quinolin-6-one derivatives via multicomponent reaction of 4-hydroxycoumarin, anilines and benzaldehydes. The nanocatalyst is magnetically separable and easily recoverable and showed successful activity up to 10 runs.

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In this work, a complex of dysprosium and balsalazide was trapped between the functionalized g-C 3 N 4 and halloysite via a simple approach. The resulting [Hal-BS/g-C 3 N 4 -Dy]-heterogenized complex was characterized using FT-IR, SEM, EDX, elemental mapping, XRD, ICP-OES, and TGA. The catalytic activity of [Hal-BS/g-C 3 N 4 -Dy] was examined in the synthesis of an array of biologically active pyran derivatives, that is, the 2-amino-5,10-dioxo-4-aryl-5,10-dihydro-4H-benzo[g]chromene-3-carbonitriles. This reaction was achieved in water as a green solvent under reflux condition. The desired products were obtained in excellent yields (up to 98%). In addition, the reusability of this novel catalyst was investigated for 8 cycles without losing catalytic activity and under the optimal reaction conditions. The ICP-OES test demonstrated that there was no leaching of metal during the catalytic reaction, indicating the heterogeneous manner of the catalyst.

A one-pot and efficient copper-catalyzed approach for synthesis of tetracyclic 6H-chromeno [4,3-b]quinolines through the intramolecular domino condensation-aza-Diels-Alder reaction of electron-rich anilines and Opropargylated salicylaldehydes under green conditions has been described.

An efficient approach for the synthesis of oxazoles through the Van Leusen reaction in the presence of β-cyclodextrin is described. In aqueous medium using β-cyclodextrin as a supramolecular catalyst, tosylmethyl isocyanide was deprotonated by triethylamine and subsequently underwent an addition/cyclization reaction with aldehydes to produce corresponding oxazoles in excellent yields. This protocol improves the Van Leusen reaction with the use of catalytic amounts of base at low temperature in green media.