Synthesis of Quinoxalines by a Carbon Nanotube-Gold Nanohybrid-Catalyzed Cascade Reaction of Vicinal Diols and Keto Alcohols with Diamines

Direct aerobic oxidation of alcohols into esters catalyzed by carbon nanotube-gold nanohybrids

Gold nanoparticles supported on carbon nanotubes were shown to efficiently catalyze the oxidation of alcohols to methyl esters under mild and selective reaction conditions. The reaction works with low catalyst loadings and the nanohybrid could be readily recycled and reused.

Cobalt oxide-carbon nanocatalysts with highly enhanced catalytic performance for the green synthesis of nitrogen heterocycles through the Friedländer condensation

A novel series of eco-sustainable catalysts developed by supporting CoO nanoparticles on different carbon supports, highly efficient in the synthesis of quinolines and naphthyridines, through the Friedländer condensation, are reported for the first time. Textural properties, dispersion and location of the Co-phase are influenced by the nature of the carbon support, Co-precursor salt and metal loading, having a significant impact on the catalytic performance. Thus, the presence of the mesopores and macropores in carbon aerogels together with the homogeneous distribution of the active phase favours the formation of product 3a as a function of the metal loading. However, an increase in the metal content when using CNTs indicates the formation of CoO aggregates and an optimal concentration of 3 wt% CoO was observed, providing the highest conversion values. The carbon-based catalysts herein reported can be considered to be a sustainable alternative having advantages such as easy preparation, superior stability and notably enhanced catalytic performance, operating at lower temperature and under solvent-free conditions.

Supramolecular Assembly of Gold Nanoparticles on Carbon Nanotubes: Application to the Catalytic Oxidation of Hydroxylamines

A supramolecular heterogeneous catalyst was developed by assembly and stabilization of gold nanoparticles on the surface of carbon nanotubes. A layer-by-layer assembly strategy was used and the resulting nanohybrid was involved in the catalytic oxidation of hydroxylamines under mild conditions. The nanohybrid demonstrated high efficiency and selectivity on hydroxylamine substrates.

Reduction of selective polyaromatic nitrotriptycene via an azoxytriptycene intermediate under ambient conditions using a cobalt/cobalt oxide nanocomposite (CoNC)

Selectively targeted polyaromatic 2-nitrotriptycene (M1) and 2,6,14-trinitrotriptycene (M2) were chosen as model substrates for demonstrating catalytic hydrogenation, under ambient conditions, using a cobalt/cobalt oxide based nanocomposite (CoNC) as the catalytic material.

Selective conversion of nitroarenes using a carbon nanotube-ruthenium nanohybrid

Ruthenium nanoparticles were assembled on carbon nanotubes and the resulting nanohybrid was used in the hydrazine-mediated catalytic hydrogenation of various nitroarenes, at room temperature. Depending on the solvent, a selective transformation occurred, giving either access to the corresponding aniline or hydroxylamine derivative.

Deoxygenation of amine N-oxides using gold nanoparticles supported on carbon nanotubes

Carbon nanotube-supported gold nanoparticles were found to be potent catalysts in the mild deoxygenation of amine N-oxides.

Mild and selective catalytic oxidation of organic substrates by a carbon nanotube-rhodium nanohybrid

A heterogeneous catalyst was assembled by stabilization of rhodium nanoparticles on carbon nanotubes.

Room temperature Suzuki coupling of aryl iodides, bromides, and chlorides using a heterogeneous carbon nanotube-palladium nanohybrid catalyst

Palladium nanoparticles were immobilized on multi-walled carbon nanotubes by a layer-by-layer approach, resulting in a well-defined assembly that was used as a heterogenous catalyst in Suzuki couplings.

Comparative assessment of the in vitro toxicity of some functionalized carbon nanotubes and fullerenes

Carbon nanotubes and fullerenes with different surface coatings are evaluated for their potential cytotoxicity on a panel of cell lines.