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Summary: Catalyst based on palladium nanoparticles and poly(propyleneimine) (PPI) dendrimers immobilized on mesoporous phenol-formaldehyde support was synthesized. Catalytic characteristics were evaluated in the hydrogenation of 1-octyne, 4-octyne, and 1-hexyne. High selectivity for alkenes (up to 99%) was achieved. Synthesized hybrid catalyst can be recycled without a loss of activity and additional regeneration.

The current work describes an attempt to synthesize hybrid materials combining porous aromatic frameworks (PAFs) and dendrimers and use them to obtain novel highly active and selective palladium catalysts. PAFs are carbon porous materials with rigid aromatic structure and high stability, and the dendrimers are macromolecules which can effectively stabilize metal nanoparticles and tune their activity in catalytic reactions. Two porous aromatic frameworks, PAF-20 and PAF-30, are modified step-by-step with diethanolamine and hydroxyl groups at the ends of which are replaced by new diethanolamine molecules. Then, palladium nanoparticles are applied to the synthesized materials. Properties of the obtained materials and catalysts are investigated using X-ray photoelectron spectroscopy, transmission electron microscopy, solid state nuclear magnetic resonance spectroscopy, low temperature N2 adsorption and elemental analysis. The resulting catalysts are successfully applied as an efficient and recyclable catalyst for selective hydrogenation of alkynes to alkenes at very high (up to 90,000) substrate/Pd ratios.

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The results of studying a number of reactions catalyzed by several types of soluble macromolecular catalytic systems capable of selectively binding organic substrates, namely, modified cyclodextrins, calixarenes and dendrimers are presented. The use of modified cyclodextrins as components of a catalytic system in the phenol and benzene hydroxylation by hydrogen peroxide allows one both to increase the catalytic activity and to change significantly the chemical selectivity. Phosphorilated calixarene -Rh catalytic systems was found to be catalytically active in hydroformylation of linear alkenes C 7 -C 12 . The results of experiments on the oxidation of C 7 -C 16 alkenes show that, when the ligand is the dendrimer molecule, the fraction of forming methyl ketones substantially increases for the substrates C 7 -C 9 . For the higher alkenes, this effect is not observed.

This review deals with heterogeneous hydroformylation catalysts, specifically metal complexes fixed in an organic polymer structure. It describes the main catalyst synthesis methods, provides data on hydroformylation of unsaturated compounds (including asymmetric hydroformylation), and shows how those compounds can be used. The special focus is on the systematization of data on heterogeneous catalysts developed on the basis of porous organic polymers. Due to their porous structure, resistance to organic media and the high concentration of heteroatoms they contain, these materials can be considered promising for developing highly active, selective and stable heterogeneous catalysts for hydroformylation of unsaturated compounds, particularly higher linear olefins.