M. V. Terenina

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.

Nanoheterogeneous ruthenium-containing catalysts based on dendrimers in the hydrogenation of aromatic compounds under two-phase conditions

Nanoheterogeneous catalysts based on ruthenium nanoparticles dispersed in crosslinked dendrimer matrixes with a size of polymer particles of 100–500 nm show high activity in the hydrogenation of aromatic compounds under two-phase conditions. The addition of water to the reaction medium exerts a strong promoting effect on the activity of the catalysts: The turnover frequency increases by a factor of 3–90 depending on the substrate. When bimetallic (PdRu) nanoparticles are incorporated into the catalyst composition, the rate of benzene hydrogenation increases while the rate of transformation of substituted benzenes decreases.

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.

Mesoporous organo-inorganic hybrid materials as hydrogenation catalysts

Abstract The paper concerns application of two types of organic materials – porous aromatic frameworks (PAFs) with diamond-like structure and the ordered mesoporous phenol-formaldehyde polymers (MPFs) – as supports for metal and metal sulfide nanoparticles. The obtained hybrid materials were tested in hydrogenation of various unsaturated and aromatic compounds. Ruthenium catalyst, based on PAF (Ru-PAF-30), possessed high activity in exhaustive hydrogenation of phenol into cyclohexanol with TOF value of 2700 h−1. Platinum catalyst, based on modified with sulfo-groups MPF (MPF-SO3H-Pt), was selective in semi-hydrogenation of terpenes, [α-terpinene, γ-terpinene, terpinolene, (s)-limonene]. Bimetallic Ni–W sulfide catalysts, prepared by in situ decomposition of [(n-Bu)4N]2Ni(WS4)2 within the pores of MPFs and PAFs, possessed high efficiency in hydrogenation-hydrocracking of naphthalenes as model substrates.

Unsaturated-compound hydrogenation nanocatalysts based on palladium and platinum particles immobilized in pores of mesoporous aromatic frameworks

Heterogeneous catalysts for the hydrogenation of unsaturated hydrocarbons have been synthesized on the basis of palladium and platinum nanoparticles immobilized in pores of mesoporous aromatic frameworks, which represent a new class of carbon supports with a diamond-like ordered structure. The resulting materials have been characterized by transmission electron microscopy, IR spectroscopy, and NMR spectroscopy. It has been shown that the catalyst activity in the hydrogenation reaction depends on the substrate molecule size and adsorbability on the surface of nanoparticles. Catalytic activity has been studied in the hydrogenation of a number of unsaturated compounds at temperatures of 60 and 80°C and pressures of 1.0 and 3.0 MPa.

Alkylation of phenol with olefins in the presence of catalysts based on mesoporous aromatic frameworks

Mesoporous polyaromatic frameworks (PAFs) based on tetraphenylmethane were obtained and modified with sulfonic acid groups. The compounds were characterized by solid-state 13C NMR and IR spectroscopy, low-temperature nitrogen adsorption-desorption, and transmission electron microscopy. The acidities of the PAF-1-SO3H and PAF-2-SO3H samples determined by titration were 3.99 mmol g–1 and 0.91 mmol g–1, respectively. The catalytic activity of PAF-SO3H for alkylation of phenol with linear terminal olefins was investigated. The reaction products were isomeric monoalkylphenols (C-alkylates), and alkyl phenyl ethers (O-alkylates).

Oxo Processes Involving Ethylene (a Review)

Processes for the conversion of ethylene to valuable oxygen-containing products such as propanal, propanol, propionic acid, and alkyl propionates have been surveyed. The ethylene hydroformylation and carbonylation processes have been considered, and the state-of-the-art of technologies and promising lines of scientific research have been specified. The role of oxo processes as a way of the deep conversion of refinery off-gases to valuable petrochemicals has been defined.

Hydrodearomatization catalysts based on molybdenum hexacarbonyl Mo(CO)6 supported on mesoporous aromatic frameworks

A method for synthesizing fine hydrodearomatization catalysts based on the immobilization of molybdenum carbonyl into the pores of mesoporous aromatic frameworks is proposed. It is shown that the amount of the deposited metal and the average size of the resulting particles depend on the support and the deposition method characteristics. The catalytic activity of the synthesized materials in the hydrogenation of bicyclic hydrocarbons at a hydrogen pressure of 5.0 MPa in a temperature range of 330–500°C is studied using the example of naphthalene, methylnaphthalenes, and biphenyl as model substrates.

Synthesis of phosphine-containing dipyrromethene cobalt complexes, promising ligands for homogeneous catalysis in nanomembrane reactors

Complexes of 5-(4-diphenylphosphinophenyl)dipyrromethene with trivalent cobalt (Ph2PC6H4DP)3Co (DP for dipyrromethene) were obtained for the first time, and their reaction with dicarbonylrhodium(I) acetylacetonate was investigated. The formed complex [Ph2P(Rh)C6H4DP]3Co was characterized by 1H, 13С, and 31P NMR spectroscopy. The dimensions of the ligand were estimated (by geometry optimization with PM3 method) and of the formed rhodium complex (by 2D diffusion NMR spectroscopy DOSY). The size of the complex makes it possible to detain it on membranes with the pore size of 2 nm providing an opportunity to use it in catalytic processes with subsequent separation of the catalyst and the reaction products in the nanofiltration mode. Test of 1-octene hydroformylation with the use of this catalytic system showed results similar to those with the system Rh–PPh3 both with respect to conversion in aldehydes and to the ratio of n/iso-products. Thus the fundamental possibility was demonstrated of applying the synthesized complexes in catalysis.