The present paper elicits the zinc oxide nanoparticles-assisted synthesis of a new series of seven-membered 1,4-diazepine heterocyclic compounds as potent lead scaffolds. Structures of synthesized compounds were corroborated using spectroanalytical techniques viz, FT-IR, 1H, 13C NMR, Mass, and elemental analysis. Also, Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), Energy dispersive x-ray analysis (EDAX), powder X-ray diffraction (PXRD), and Fourier transform infrared spectroscopy (FT-IR) were used to establish the structure and morphology of the synthesized nanocatalyst. The clean workup procedure, high to excellent yields, relatively short reaction times, and high atom economy are the incredible advantages associated with the protocol.

A convenient, highly efficient and time economic method has been described for the chemo- and regioselective synthesis of 5-aryloyl-1,3,7,9-tetraalkyl-2,8-dithioxo-2,3,8,9-tetrahydro-1H-pyrano[2,3-d:6,5-dˊ]dipyrimidine-4,6(5H,7H)-diones derivatives by one-pot two-component reaction of 1,3-diethyl-2-thiobarbituric acid or 1,3-dimethyl-2-thiobarbituric acid with substituted arylglyoxalmonohydrates using commercially available zirconium (IV) oxydichloride octahydrate (ZrOCl2.8H2O) as green Lewis acid catalyst. This method is associated with some attractive characteristics such as good selectivity, very short reaction time, high yield of products, cleaner reaction profile, no harmful by-product, cheap and environmental benign catalyst, simple experimental and work-up procedure. This procedure does not require solvent separation and purification steps such as column chromatography.

An efficient one-pot synthesis of pyrano[2,3-c]pyrazoles via four-component reaction of phenyl hydrazine, ethyl acetoacetate, malononitrile and aromatic aldehydes, catalyzed by poly(4-vinylpyridine) is reported. This method provides many advantages such as, atom-economy, easy work up, clean procedure, short reaction times and high yields of products.