E.A. Runova

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.

Surface active macromolecular and supramolecular complexes: design and catalysis

A number of macromolecular and supramolecular catalysts which combine the functions of transition metal complex, phase transfer agent with molecular recognition ability has been designed. The complexes of rhodium, palladium, iron and copper showed the remarkable activity in hydroformylation, Wacker-type oxidation of various olefins, oxidation of alkanes and hydroxylation of aromatics.

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.

Methylformate as replacement of syngas in one-pot catalytic synthesis of amines from olefins

A new general approach for the one-pot hydroaminomethylation of olefins using methylformate as formylating agent instead of synthesis gas (syngas) has been proposed. Herein we report that a Ru–Rh catalytic system demonstrates high activity in a tandem conversion of a series of n-alkenes into amines using methylformate with yields 58–92% (6 h). The selectivity for the normal amine reached 96% with catalysis by the Ru carbonyl complex Ru3(CO)12, with an overall yield of 55% with respect to amine in this instance. The addition of the Rh complex to Ru catalytic system, sharply increased the hydroaminomethylation rate of both the terminal and internal alkenes and increased the yield of amines to 82–93% (6–12 h).

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.

Use of ionic liquids in cyclohexene epoxidation with hydrogen peroxide

A comparative study of the reaction of catalytic epoxidation of cyclohexene with hydrogen peroxide in water and ionic liquids containing dihydrogen phosphate anions, such as trimethylammonium dihydrogen phosphate, diethylammonium dihydrogen phosphate, and N-methylpyrrolidonium dihydrogen phosphate has been performed. It has been shown that as high a cyclohexane epoxide yield as 80% with a selectivity close to quantitative can be obtained under optimum conditions by controlling the ratio of the ionic liquid components.

Hydroformylation of olefins catalyzed by rhodium complexes with phosphinitecalix[4]arenes

Hydroformylation of alkenes with various carbon chain lengths and arylalkenes in the presence of the catalytic system consisting of Rh(acac)(CO)2 and phosphinitecalix[4]arenes was studied. The influence of the P/Rh and substrate/catalyst ratios, temperature, and pressure on the process and the product composition was examined.

Mass-spectrometric behavior of N-substituted 2-methyl-3-acetyl pyrroles

In the dissociation of N-substituted derivatives of 2-methyl-3-acetylpyrroles by the action of electron impact, the methyl group splits off from the acetyl substituent, and then the exocyclic N-C bond is ruptured due to the preferential localization of the charge on the C(2)-C(3) bond in the pyrrole ring.

Interaction of ethoxyacetaldehyde with 1,3-dicarbonyl compounds

It has been established that on interaction of ethoxyacetaldehyde with acetyl-acetone, acetoacetic ester, and benzoylacetone in the presence of piperidine acetate, β,γ-unsaturated compounds are formed, viz., 3-(2-ethoxy)vinyl substituted acetylacetone, acetoacetic ester, and benzoylacetone. Methods are proposed for the synthesis of 2,3,5-trisubstituted 4,5-dihydrofurans in the presence of trifluoroacetic or acetic acids by the cylization of the linear condensation products.