Chemoselective Synthesis of Pentaerythritol Diacetals Catalyzed by CuO-CeO 2 Nanocomposite under Solvent-free Conditions

Abstract CuO-CeO 2 nanocomposite is reported as a green recyclable catalyst for the chemoselective synthesis of pentaerythritol diacetals from aromatic aldehydes under solvent-free conditions. The catalyst was synthesized by co-precipitation method and characterized by XRD, BET specific surface area, FESEM and EDS analysis. This procedure provides some advantages such as simple work-up, clean procedure, short reaction times and high yields of the products

Melamine trisulfonic acid catalyzed regioselective nitration of aromatic compounds with sodium nitrate under solvent-free conditions

A simple and efficient method for the regioselective nitration of various aromatic compounds by using sodium nitrate in the presence of melamine trisulfonic acid, is reported. This method provides several advantages such as good selectivity between ortho and para positions of aromatic compounds, simple work-up, short reaction times and high yields of the products

Aerobic Oxidation of Alcohols Catalyzed by a New ZnO-Supported Copper Oxide Nanocatalyst in Aqueous Media

<div><p></p><p>ZnO-supported copper oxide nanocatalyst is reported as an efficient recyclable catalyst for the aerobic oxidation of alcohols in the presence of oxygen as the oxidant. The catalyst was prepared by coprecipitation method and characterized by x-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and transmission electron microscopy (TEM) analysis. A variety of primary and secondary alcohols were oxidized into the corresponding carbonyl compounds in good to excellent yields. The catalyst can be recovered by simple filtration and recycled up to five consecutive runs without significant decrease in the catalytic activity.</p></div

Novel Metal Oxide of CuO-ZnO Nanocatalyst Efficiently Catalyzed the Synthesis of 2-Amino-4<i>H</i>-chromenes in Water

<div><p></p><p>Novel metal oxide of CuO-ZnO nanocatalyst was prepared by a coprecipitation method and characterized by x-ray diffusion, Brunauer–Emmett–Teller surface area, scanning electron microscopy, transmission electron microscopy, and energy dispersive spectroscopy (EDS) analysis. The catalyst is efficient for the synthesis of 2-amino-4<i>H</i>-chromenes by one-pot condensation of aromatic aldehydes, hydroxynaphthalene derivatives, and malononitrile in water at reflux conditions. Moreover, CuO-ZnO nanocatalyst can be recycled up six times without any significant loss of its catalytic activity.</p></div

Introduction of efficient catalytic system for the regioselective aerobic bromination of aromatic compounds

A highly regioselective aerobic bromination of aromatic compounds has been achieved using Fe3O4@SiO2/CuO nanocatalyst and O2 as a green oxidant. In this procedure, the reactions gave high yields and para-selectivity for the various aromatic compounds. Mechanistic studies are described, and the possible mechanisms are proposed. Recyclability of the Fe3O4@SiO2/CuO nanocatalyst has also been explored upon aerobic bromination of aromatic compounds. The nanocatalyst can be reused five times without any significant decrease in the catalytic activity and selectivity.</p