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The novel developed heterogeneous catalyst Ad/Pd‐UiO‐66 has been synthesized by hydrothermal technique. The prepared catalyst was identified by some analytical techniques such as Fourier transform‐infrared spectroscopy (FT‐IR), high‐resolution transmission electron microscopy (HR‐TEM), X‐ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), X‐ray diffraction (XRD), and field emission scanning electron microscopy (FE‐SEM). The Ad/Pd‐UiO‐66 was used as catalyst in the Suzuki C–C coupling in the green aqueous media. This catalyst showed excellent efficiency for the C–C coupling of aryl halides with phenylboronic acid and 4‐methyl phenylboronic acid. The best results was recorded for coupling of iodobenzene with phenylboronic acid (95% conversion in 30 min). Furthermore, the stability and recyclability of the catalyst under optimized conditions were investigated. The catalyst was recovered and reused up to 5 times with no significant decrease in activity. [ABSTRACT FROM AUTHOR]

A novel Mo(VI) tetradentate Schiff base complex based on two pyrrole-imine donors was anchored covalently on Fe3O4 nanoparticles and characterized using physicochemical techniques. The catalytic epoxidation process was optimized in terms of the effects of solvent, reaction temperature, kind of oxidant and amount of oxidant and catalyst. Then the novel heterogeneous nanocatalyst was used for the efficient and selective catalytic epoxidation of internal alkenes (cyclohexene, cyclooctene, α-pinene, indene and trans-1,2-diphenylethene) and terminal alkenes ( n-heptene, n-octene, n-dodecene and styrene) using tert-butyl hydroperoxide (70% in water) as oxidant in 1,2-dichloroethane as solvent. The prepared nanocatalyst is very effective for the selective epoxidation of cis-cyclooctene with 100% conversion, 100% selectivity and turnover frequency of 1098 h−1 in just 30 min. The magnetic nanocatalyst was easily recovered using an external magnetic field and was used subsequently at least six times without significant decrease in conversion. [ABSTRACT FROM AUTHOR]

A novel heterogeneous composite material based on reduced graphene oxide (rGO) and bismuth vanadate (BiVO4) was prepared and characterized by various techniques such as powder XRD, HRTEM, EADX, UV–Vis‐DRS, FT‐IR, Raman, BET and XPS analyses. The characterization results reveal that the rGO well decorated by BiVO4. The electrochemical impedance spectroscopy (EIS) shows the increasing of charge transfer of rGO/BiVO4 in presence of light irradiation. In this research, the pure BiVO4 and rGO/BiVO4 composite have been explored for photocatalytic reduction of nitroarenes. Among the prepared nanocomposites, rGO loaded with 10% BiVO4 catalyst (noted as rGO/BiVO4–10%) shows the best performance for the photo‐reduction of various nitroaromatic molecules to their corresponding amine compounds under visible‐light irradiation at room temperature. The catalyst exhibited in particular excellent photocatalytic activity for the conversion of 1,4‐dinitrobenzene to 4‐nitroanilline (100% conversion) in 20 min, 4‐chloronitrobenzene to 4‐chloroaniline and 2‐nitrophenol to 2‐aminophenol (100% conversion) in only 30 min. In addition, the conversion of 4‐bromonitrobenzene, 4‐iodonitrobenzene to their corresponding amine compounds (100% conversion) was achieved in 60 min. The catalyst was recovered for several times and reused without decreasing of its efficiency. [ABSTRACT FROM AUTHOR]

A novel heterogeneous composite material based on reduced graphene oxide (rGO) and bismuth vanadate (BiVO4) was prepared and characterized by various techniques such as powder XRD, HRTEM, EADX, UV–Vis‐DRS, FT‐IR, Raman, BET and XPS analyses. The characterization results reveal that the rGO well decorated by BiVO4. The electrochemical impedance spectroscopy (EIS) shows the increasing of charge transfer of rGO/BiVO4 in presence of light irradiation. In this research, the pure BiVO4 and rGO/BiVO4 composite have been explored for photocatalytic reduction of nitroarenes. Among the prepared nanocomposites, rGO loaded with 10% BiVO4 catalyst (noted as rGO/BiVO4–10%) shows the best performance for the photo‐reduction of various nitroaromatic molecules to their corresponding amine compounds under visible‐light irradiation at room temperature. The catalyst exhibited in particular excellent photocatalytic activity for the conversion of 1,4‐dinitrobenzene to 4‐nitroanilline (100% conversion) in 20 min, 4‐chloronitrobenzene to 4‐chloroaniline and 2‐nitrophenol to 2‐aminophenol (100% conversion) in only 30 min. In addition, the conversion of 4‐bromonitrobenzene, 4‐iodonitrobenzene to their corresponding amine compounds (100% conversion) was achieved in 60 min. The catalyst was recovered for several times and reused without decreasing of its efficiency. [ABSTRACT FROM AUTHOR]