Yu. S. Kardasheva

Macrocomplexes on the basis of functionalized polyethylene glycols and copolymers of ethylene oxide and propylene oxide: synthesis and catalysis

Water soluble catalysts combining the properties of metal complexes and surfactants on the basis of terminally functionalized polyethylene glycols and block-copolymers of ethylene oxide and propylene oxide with various combinations of ethylene and propylene oxide fragments were investigated. Polymers, functionalized by dipyridyl and acetylacetone were used as ligands for preparation of Fe(III) and Co(II) complexes, which showed a high activity and selectivity in oxidation of cyclohexane and ethylbenzene by both hydrogen peroxide and oxygen. An aqueous phase hydroformylation rhodium catalyst was prepared on the basis of polyethylene glycols functionalized by phosphine groups.

Surface active rhodium catalysts for hydroformylation of higher alkenes in two-phase systems

Abstract A variety of water-soluble phosphine and phosphite ligands with phase-transfer ability based on functionalized polyethylene oxide has been synthesized. The corresponding rhodium complexes show high catalytic activity in aqueous biphasic hydroformylation of higher alkenes under mild conditions. The catalysts can be easily separated from products and reused. The effect of ligands structure, temperature, ligand-to-rhodium ratio, addition of free PPh3 and P(OPh)3 on catalytic stability and activity is studied.

Iron and copper complexes with nitrogen-containing ligands as catalysts for cyclohexane oxidation with hydrogen peroxide under mild reaction conditions

Oxidation of cyclohexane (CH) with hydrogen peroxide under mild reaction conditions in the presence of systems containing in situ generated iron complexes with nitrogen-containing ligands (2,2′-bipyridyl and o-phenanthroline) and chlorinated (Cl15) copper phthalocyanine (CuPcCl15) have been studied. It has been shown that in water-acetonitrile blends under optimum conditions, CH is oxidized with the formation of cyclohexanol, cyclohexanone, and acids involving cyclohexane hydroperoxide. High total selectivity for ketone and alcohol is reached in the excess of ligands and the substrate.

Hydrogenation of phenols in ionic liquids on rhodium nanoparticles

A new catalyst system based on rhodium nanoparticles stabilized by polyacrylic acid have been suggested for the hydrogenation of phenols in ionic liquids. It has been shown that high near-quantitative yields of reaction products are achieved in ionic liquids containing a tetraalkylammonium cation. By the TEM and XPS techniques it has been revealed that the use of ionic liquids substantially decreases the particle size and reduces the aggregation of nanoparticles through the inclusion of the ionic liquid cations into the surface layer along with polyacrylic acid.

Platinum and palladium nanoparticles in modified mesoporous phenol—formaldehyde polymers as hydrogenation catalysts

Mesoporous polymeric supports modified with sulfo groups and PPI dendrimers have been prepared. Catalysts containing palladium and platinum nanoparticles have been synthesized on their basis. The resulting catalysts have been studied by transmission electron microscopy and X-ray photoelectron spectroscopy. It has been shown that the metal deposition procedure has an effect on the morphology of the resulting catalyst. Catalytic activity has been studied using the example of the hydrogenation of phenylacetylene and naphthalene at temperatures of 80 and 400°C, and pressures of 1.0 and 5.0 MPa, respectively.

Hydrogenation catalysts based on metal nanoparticles stabilized by organic ligands

The review analyses principal approaches to the synthesis of hydrogenation catalysts based on noble metal nanoparticles stabilized by different organic ligands, such as alcohols, amines, phosphines, ionic liquids, linear polymers, and dendrimers. A possibility of application of new materials, the so-called “breathing” metal-organic frameworks, as matrices for the development of heterogeneous catalysts was considered.

Rhodium-calix[6]arene diphosphite complex as olefin hydroformylation catalyst

A rhodium-calix[6]arene diphosphite complex was used as a catalyst in the hydroformylation reaction of linear alkenes and styrenes. The influence of P/Rh and substrate/catalyst ratios, as well as temperature and pressure, on the aldehyde yield and the regioselectivity of the process was studied. The complexation of calix[6]arene diphosphite with Rh(acac)(CO)2 was studied by 1H and 31P NMR spectroscopy and atmosphericpressure electrospray ionization (AP-ESI) mass spectrometry.

Thermo-responsive Ruthenium Dendrimer-based Catalysts for Hydrogenation of the Aromatic Compounds and Phenols

In this work thermo-responsive ruthenium catalysts, based on the poly(propylene imine) dendrimers cross-linked with the poly(ethylene glycol) diglycidyl ether, have been prepared for the first time. The materials obtained were characterized by X-ray photoelectron spectroscopy and transmission electron microscopy, and tested in the phenol and benzene hydrogenation. Conditions for the metal impregnation into the polymeric matrix were demonstrated to have a great influence both on physical chemical properties of the synthesized catalysts (metal loading, mean particles size, surface structure etc.), and, as a consequence, on their hydrogenation activity and thermo-responsive properties.

Catalytic aminomethylation of alkenes in a dimethylformamide medium

The hydroaminomethylation of alkenes with dimethylamine catalyzed by rhodium and ruthenium complexes in a dimethylformamide medium under synthesis-gas pressures of 2 MPa has been studied. It has been shown that the combined use of these metals leads to a significant increase in the rate of formation of amines and selectivity for n-alkyldimethylamine. It has been found that the reaction can proceed with dimethylformamide used as an aminating agent without the addition of dimethylamine.

Hydroconversion of kerogen-containing raw materials into synthetic crude oil

The hydroconversion of kerogen-containing rock (oil shale) into synthetic crude oil was studied, and an optimum combination of catalytic additives, extractants, and modifiers in the hydroprocessing was found to ensure reasonable yields and quality of the synthetic oil. With the use of modifiers and catalytic additives, is possible to increase the conversion of kerogen into shale oil to a value of >90%. The modifiers and additives based on a mixture of cobalt and molybdenum compounds exhibited the greatest activity.