New heterogeneous hydrogenation catalysts, based on Pd nanoparticles and polypropyleneimine (PPI) dendrimers of the third generation that have been covalently grafted to a silica surface modified with polyallylamine (PAA) have been synthesized. The final products were characterized by TEM, XPS, and solid-state NMR spectroscopy. The synthesized materials are effective catalysts for selective hydrogenation of dienes to monoenes and phenyl acetylene to styrene at very high substrate/Pd ratios with turnover rates higher than related Pd nanoparticle catalysts. The synthesized catalysts can be reused without any loss of activity in the case of styrene and isoprene.

Novel catalysts consisting of ruthenium nanoparticles encapsulated in cross‐linked matrices based on the poly(propylene imine) dendrimers of the 1st and 3rd generations have been synthesized with a narrow particle size distribution (3.8 and 1.0 nm, respectively). The resulting materials showed high activity for the hydrogenation of phenols in aqueous media (specific catalytic activity reached turnover frequencies of 2975 h−1 with respect to hydrogen uptake). It has been shown that the use of water as a solvent leads to a 1.5 to 50‐fold increase in the reaction rate depending upon the nature of the substrate. It has been established that unlike the traditional heterogeneous catalysts based on ruthenium, during the hydrogenation of dihydroxybenzenes, the hydrogenation rate decreases in the order: resorcinol>hydroquinone≫catechol. The maximum specific activity for resorcinol was a turnover frequency of 243150 h−1 with respect to hydrogen uptake. The catalyst based on the dendrimer of the 3rd generation containing finer particles has significantly inferior activity to the catalyst based on the dendrimer of the 1st generation by virtue of steric factors, as well as the need for prereduction of the ruthenium oxide contained on the surface. These catalysts showed resistance to metal leaching and may be reused several times without loss of activity.

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Nanostructured regular materials based on dendrimers bound by covalent or coordination bonds between surface functional groups were synthesized. Bimetallic Cu(II) and Pd(II) metal complexes with nitrile-based dendrimers demonstrated high activity in Wacker oxidation of terminal alkenes along with good selectivity for methylketone formation. New heterogeneous catalysts based on Pd nanoparticles and cross-linked polypropylene imine (PPI) and polyamidoamine (PAMAM) dendrimers were prepared and examined for selective hydrogenation of unsaturated compounds.

New hybrid catalysts based on Ru nanoparticles, encapsulated into poly(propylene imine dendrimers), immobilized into silica pores, were synthesized and examined for the hydrogenation of alkyl-substituted phenols. The corresponding alkyl-substituted cyclohexanols were presented as the major reaction products, while incomplete hydrogenation products appeared to be minor. A competition between the sterical factors of dendrimer-containing carriers and the electronic factors of substrate substituents influenced the hydrogenation rate of the alkyl-substituted phenols. The carrier structure was found to have a significant influence on both the physical and chemical properties of the catalysts and their hydrogenation activity. The synthesized hybrid catalysts appeared to be stable after recycling and could be re-used several times without significant loss of activity.

The interest in functional supramolecular systems for the design of innovative materials and technologies, able to fundamentally change the world, is growing at a high pace. The huge array of publications that appeared in recent years in the global literature calls for systematization of the structural trends inherent in the formation of these systems revealed at different molecular platforms and practically useful properties they exhibit. The attention is concentrated on the topics related to functional supramolecular systems that are actively explored in institutes and universities of Russia in the last 10–15 years, such as the chemistry of host–guest complexes, crystal engineering, self-assembly and self-organization in solutions and at interfaces, biomimetics and molecular machines and devices. The bibliography includes 1714 references.

Halloysite is a natural tubular aluminosilicate clay of ca. 50 nm diameter and 0.5–1.5 micrometers in length. The nanoarchitectural modification of halloysite inner/outer surfaces can be achieved through supramolecular and covalent interactions exploiting its different inside/outside chemistry (Al2O3/SiO2). The tubular morphology makes halloysite a prospective nanotemplate for core-shell structured mesoporous catalysts. Catalytic metals can be incorporated on the nanotubes’ outer surface or in the inner lumens with selective metal binding. 2–5 nm diameter Au, Ag, Pt, Pd, Co, Ru, Cu-Ni, Fe2O3, CoxBy, CdS, and CdxZn1−xS particles were templated on halloysite. In this work, CdS and Ru-containing halloysite based nanocatalysts were synthesized via modification with organic ligands and microwave-assisted wetness ion impregnation. The catalytic hydrogenation of benzene and its homologues as well as phenol was performed. The impacts of the core-shell architecture, the metal particle size and seeding density were optimized for high reaction efficiency. An efficient Co-halloysite catalyst was formed using azines as ligands, and it contained 16 wt. % of cobalt with hydrogen evolution rate of 3.0 L/min × g(cat). The mesocatalysts produced are based on a safe and cheap natural clay nanomaterial and may be scaled-up for industrial applications.

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