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Sm, Er, and Yb complexes containing anionic (4,5,6,7-tetrafluorobenzothiazol-2-yl)-2-(3,4,5,6-tetrafluoro)phenolate (SONF) and 3-(2-benzothiazol-2-yl)-2-naphtholate (NpSON) and neutral 1,10-phenathroline or 2,2'-bipyridine ligands were synthesized. The structures of complexes Yb(SONF)2-(NpSON)(DME)1.5 (II) and previously synthesized Er(SONF)3(DME) (I) were determined by X-ray diffraction (CIF files CCDC nos. 1972769 and 1972770, respectively). Upon excitation by light at λ 405 nm, all complexes showed luminescence of the ligands and Ln3+ ions. The OLED devices based on samarium complexes showed moderate intensi metal-centered emission of moderate intensity at a 19 V voltage.

This paper reports the investigation of copolymerization of acrylonitrile with methyl acrylate, dimethyl maleate, dimethyl fumarate and dimethyl itaconate via atom transfer radical polymerization mechanism using copper bromide as a catalyst in combination with tris(2-pyridylmethyl)amine as a ligand. The reactivity ratios of monomers were evaluated using the Finemann–Ross and Kelen–Tudos methods basing on the copolymer composition determined by 1H NMR spectroscopy. It was found that reversible deactivation mechanism has no significant influence on the monomer reactivity ratios. It was found that among the tested comonomers methyl acrylate and dimethyl itaconate seem to be the most suitable ones for obtaining well-defined copolymers of acrylonitrile.

The synthesis of complexes LnI(C6F5O)2 and LnCp(L)2 (Ln = Er, Yb; L = C6F5O, SONF), which are convenient precursors for the preparation of heteroligand bimetallic complexes, is described. The structures of YbI(C6F5O)2(DME)2 (I), CpEr(C6F5O)2(DME)[(C2H5)2O] (III), and CpYb(SONF)2(DME) (VI) were established by X-ray diffraction (CIF files CCDC (nos. 1902963 (I), 1902964 (III), and 1902965 (VI)). The developed methods were used to prepare heteroligand bimetallic Yb(III)–Er(III) complexes (C6F5O)2Yb[µ-(CF3)2CHO]2Er(C6F5O)2 and {(SONF)2Yb[µ-(CF3)2CHO]2-Er(SONF)2}x, which showed metal-centered emission inherent in Yb3+ and Er3+ ions λem = 985 and 1540 nm, respectively. This suggests that the obtained compounds can serve as promising upconversion materials.

The controlled synthesis of poly(stearyl methacrylate) and stearyl methacrylate–acrylonitrile copolymers is conducted using a catalytic system consisting of copper(I) bromide, tris[(2-pyridyl)methyl]amine as a ligand, and isopropylamine as an activating agent. Effects of activator concentration and monomer mixture composition on the molecular-weight characteristics of the (co)polymers are estimated. It is shown that the products of synthesis may be used as depressor additives lowering the cloud point, pour point, and cold filter plugging point of diesel fuel.

The radical polymerization of methyl methacrylate catalyzed by systems based on the carborane complexes of ruthenium(III) is studied in the presence of a number of activating agents: tin 2-ethyl hexanoate, aluminum isopropoxide, isopropylamine, and AIBN. It is shown that in the presence of the systems under consideration, polymerization proceeds in a controlled mode via the ATRP mechanism (AGET or ICAR ATRP) at catalyst concentrations with ppm level relative to that of the monomer. As the degree of monomer conversion grows, the molecular weight of the polymer increases linearly while its polydispersity coefficients decrease linearly. The role of the mentioned agents is to transfer the catalyst to the active form containing a metal atom in the oxidation number +2 and able to interact with halogen-terminated dormant polymer chains. It is first shown that the carborane complexes of ruthenium(II) are applicable for the catalysis of controlled radical polymerization.

Specific features of copolymerization of acrylonitrile with dimethyl maleate and dimethyl fumarate under the action of a catalytic system based on copper(I) bromide and tris[(2-pyridyl)methyl]amine were studied. The polymerization occurs in the controlled mode, with the molecular weight of the copolymers increasing with conversion. The formation of the copolymers was proved by NMR spectroscopy. Introduction of the comonomers smooths the exothermic effect observed in oxidative stabilization of the polyacrylonitrile precursor.

The polymerization of acrylonitrile in the presence of catalytic systems based on copper(I) bromide, tris(2-pyridylmethyl)amine, and different reducing/activating agents is studied. It is found that the polymerization is controlled and that the activating agent is regenerated by a single-electron transfer. Moreover, the polymerization leads to the formation of polymers with high molecular weight and relatively narrow molecular-weight distribution. It is found that glucose and ascorbic acid are the most efficient among the studied activating agents in terms of the polymerization rate and the control over the molecular-weight characteristics of synthesized polymers.

An additive based on stearyl methacrylate–vinyl acetate copolymer was synthesized by the method of controlled atom transfer radical polymerization. The additive simultaneously improves the low-temperature properties of hydrotreated diesel fuels and enhances their resistance to thermal oxidation to meet the European quality standards. Comparative analysis of the effect exerted on the characteristics of environmentally clean diesel fuel by the synthesized additive and Dodiflow commercial depressor additive was made, and the negative effect of the latter on the thermo oxidative stability of diesel fuel was revealed of the fuel to thermal oxidation was revealed.

We studied the effect of bis[4,6-di-tert-butyl-N-(2,6-dimethylphenyl)-ortho-iminobenzosemi-quinono]cobalt(II) on the kinetics of the bulk polymerization of methyl methacrylate at 70°C and on the molecular-weight characteristics of the polymer synthesized. The effective chain transfer constant in the polymerization of methyl methacrylate in the presence of the complex in benzene at 70°C was determined by the Mayo method and by linearizing the macromolecule chain length distribution. The constants obtained were compared with the same parameters available from the literature for a number of known chain-transfer agents, viz., dodecyl mercaptan and cobalt porphyrin and oxime complexes.

The radical polymerization of isobornyl acrylate, isobornyl methacrylate, and tert-butyl methacrylate under conditions of catalysis by ruthenium compounds is studied. It is found that the catalytic system based on the carborane complex of ruthenium 3,3-{[1,1-diphenyl-6-phenyl-6-(6,8-(o-phenylene))]-1,6-diphosphahexane}-3-chloro-closo-3,1,2-dicarbollyl ruthenium and isopropylamine makes it possible to conduct the controlled free-radical polymerization of the mentioned monomers via the Atom Tranfer Radical Polymerization mechanism. The molecular weights of the polymers linearly increase, while their polydispersity coefficients linearly decrease during the process. Block copolymers are synthesized on the basis of the above monomers, and the molecular-weight characteristics and glass-transition temperatures of these copolymers are measured.

Catalytic systems based on carborane complexes of ruthenium with long-chain diphosphine ligands, such as 1,4-bis(diphenylphosphino)butane and 1,5-bis(diphenylphosphino)pentane, are prepared for the controlled radical polymerization of methyl methacrylate. It is found that the used metallacarboranes can catalyze polymerization initiated by both carbon tetrachloride and 2,2′-azo-bis(isobutyronitrile). It is shown that closo-ruthenacarborane with 1,5-bis(diphenylphosphino)pentane 3,3-[PPh2(CH2)5PPh2]-3-Cl-3,1,2-closo-RuC2B9H11 and its o-phenylenecycloborated derivatives make it possible to conduct polymerization at higher rates than those attained with the use of previously synthesized complexes based on diphosphines with a smaller length of the hydrocarbon fragment. The relationship between the redox potential of the complex and the efficiency of control over molecular-mass characteristics of the polymers is analyzed. Experiments reveal that the addition of small amounts of aliphatic amines causes a considerable increase in the rate of polymerization and leads to a decrease in the concentration of the catalyst with retention of a high degree of control over the process.

The radical polymerization of methyl methacrylate catalyzed by systems based on paramagnetic closo-ruthenacarboranes with diphosphine ligands is studied. Effects of the structure of metallocomplex catalysts on the rate of polymerization and the molecular-mass characteristics of the polymers are investigated. It is shown that the addition of amines to the reaction solution makes it possible to reduce the concentration of metallacarborane catalysts to hundredths of a percent, while control over the polymerization process remains at a high level.

The effects of amines on the activity of ruthenium catalysts in the controlled synthesis of poly(methyl methacrylate) are reported at 80°C. The introduction of tert-butylamine or triethylamine into the polymerization system raises the polymerization rate by 1–2 orders of magnitude without reducing the high degree of control over the chain propagation step. The “living” character of methyl methacrylate polymerization in the presence of ruthenacarboranes and amines is proved by the fact that, as the monomer conversion increases, the molecular weight of the resulting polymer increases linearly and the polydispersity index decreases. The polymer can serve as a macroinitiator for postpolymerization and block copolymer synthesis.