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The laser ablation technique was utilized to fill the carboxy methyl cellulose (CMC) solution with zirconium dioxide (ZrO2) and copper oxide (CuO) nanoparticles with different concentrations. Different techniques have been used to study the physical behavior of fabricated compositions. CuO has shown different peaks at related to the monoclinic phase of the prepared CuO NPs lattice constants (JCPDS No. 02-1225). According FTIR results, ZrO2 has exhibited vibrating bands at 460 cm−1, 477 cm−1, 670 cm−1, and 690 cm−1 which are corresponding to Zr–O vibration. In addition, CuO has shown vibrating bands at 439, 494, and 594 cm−1. The dielectric properties have been investigated. The TGA results showed that the sample CMC-ZrO2-CuO/20 min has excellent thermal stability as the weight loss is 36% of its initial weight at 796 °C. The optical and electrical characterization showed that the addition of ZrO2 and CuO has changed and enhanced the electrical characterization of CMC. The enhancement in electrical conductivity of the system encourages it for electrical applications. [ABSTRACT FROM AUTHOR]

The synthesis of mixed-ligand complexes is considered an important strategy for developing new metal complexes of enhanced biological activity. This paper presents the synthesis, characterization, in vitro antimicrobial assessment, and theoretical molecular docking evaluation for synthesized oxidovanadium (V) complexes. The proposed structures of the synthesized compounds were proved using elemental and different spectroscopic analysis. The antimicrobial tests showed moderate activity of the compounds against the Gram-positive bacterial strains and the fungal yeast, whereas no activity was observed against the Gram-negative bacterial strains. The performance of density functional theory (DFT) was conducted to study the interaction mode of the targeted compounds with the biological system. Calculating the quantitative structure-activity relationship (QSPR) was performed depending on optimization geometries, frontier molecular orbitals (FMOs), and chemical reactivities for synthesized compounds. The molecular electrostatic potentials (MEPs) that were plotted link the interaction manner of synthesized compounds with the receptor. The molecular docking evaluation revealed that the examined compounds may possess potential antibacterial activity. [ABSTRACT FROM AUTHOR]

Over the last two decades, N-heterocyclic carbene (NHC)-copper catalysts have received considerable attention in organic synthesis. Despite the popularity of copper complexes containing monodentate NHC ligands and recent development of poly(NHC) platforms, their application in C-C and C-heteroatom cross-coupling reactions has been limited. Recently, we reported an air-assisted Sonogashira-type cross-coupling catalyzed by well-defined cationic copper-pincer bis(NHC) complexes. Herein, we report the application of these complexes in Ullmann-type C-X (X = N, O) coupling of azoles and phenols with aryl halides in a relatively short reaction time. In contrast to other well-defined copper(I) catalysts that require an inert atmosphere for an efficient C-X coupling, the employed Cu(I)-pincer bis(NHC) complexes provide good to excellent yields in air. The air-assisted reactivity, unlike that in the Sonogashira reaction, is also affected by the base employed and the reaction time. With Cs 2 CO 3 and K 2 CO 3 , the oxygen-generated catalyst is more reactive than the catalyst formed under argon in a short reaction time (12 h). However, the difference in reactivity is compromised after a 24 h reaction with K 2 CO 3 . The efficient pincer Cu-NHC/O 2 /Cs 2 CO 3 system provides great to excellent cross-coupling yields for electronically diverse aryl iodides and imidazole derivatives. The catalyst scope is controlled by a balance between nucleophilicity, coordinating ability, and the steric hindrance of aryl halides and N-/O-nucleophiles.