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A conjugated planar dicobalt binuclear phthalocyanine 2CoCo exhibits extremely high catalytic activity in the oxidation of a thiol to the corresponding disulfide. Therefore this complex is interesting in the petroleum industry for the desulfurization of petroleum fractions. It is now necessary to study the reason and mechanism of the high activity of the cobalt complex. We describe the synthesis of different monocobalt binuclear Pcs 2CoM[Formula: see text] where the second Pc ring with M[Formula: see text] is either metal-free or metalated with Zn(II) or Ni(II) which were found to be redox-inactive in their Pc complexes. Then the catalytic activities of these heterometallic binuclear complexes are compared with the activity of the binuclear 2CoCo. Further, the activity of the mononuclear 1Co is considered for comparison. On the basis of the data obtained, it can be decided whether the high catalytic activity of the binuclear 2CoCo is a result of a cobalt-cobalt electronic exchange or a [Formula: see text]-system extension.

Atom Transfer Radical Polymerization (ATRP) is an effective catalytic process leading to well-defined polymers with desired properties. This process based on reversible deactivation of propagating chains has a lower rate in comparison with conventional radical polymerization, especially in the case of obtaining polymers with high molecular weights. Thus, the increase of the rate of this process with preserving control over molecular weight distribution is a challenging task. In this work, novel catalytic systems for Activators Generated by Electron Transfer (AGET) ATRP of acrylonitrile based on copper (II) bromide complexes were proposed. It was found that Rochelle salt (potassium sodium tartrate tetrahydrate) may be used as a reducing agent for regeneration of copper-based catalysts to increase the rate of the process. The provided UV-vis spectroscopy experiments have confirmed the reducing ability of tartaric anion. It was found that the use tandem catalytic system based on two copper complexes with different ligands also increases the polymerization rate. The performed experiments allowed us to develop a catalytic system for rapidly obtaining polyacrylonitrile polymers with desired molecular weights exceeding 100 kDa.

The visible light-induced polymerization of methyl methacrylate in the presence of methylene blue as a photocatalyst and various bromine-containing organic compounds was first investigated. It was shown that polymerization may be successfully initiated even at low concentrations of methylene blue using conventional LED strips. The polymerization rate and the dependency of molecular weight parameters of the samples on monomer conversion are governed by the nature of light source as well as the structure of the initiator and introducing additional reagents. The use of warm white light seems to be more favorable for conducting the process to high conversions. Electron-donating additives such as aliphatic amines or formic acid accelerate the polymerization and determine the linear increase of molecular weight of the samples with the conversion growth typical for reversible deactivated radical polymerization. The performed quantum-chemical calculations and experimental studies show that the simultaneous realization of the metal-free atom transfer radical polymerization and light-induced stable free radical polymerization mechanisms is possible under the light irradiation. The simultaneous realization of two different processes determines the linear growth of the polymer chain upon conversion but results in average control over molecular weight distribution of the obtained samples.

Major trends in controlled radical polymerization (CRP) or reversible-deactivation radical polymerization (RDRP), the most efficient method of synthesis of well-defined homo- and copolymers with specified parameters and properties, are critically analyzed. Recent advances associated with the three classical versions of CRP: nitroxide mediated polymerization, reversible addition-fragmentation chain transfer polymerization and atom transfer radical polymerization, are considered. Particular attention is paid to the prospects for the application of photoinitiation and photocatalysis in CRP. This approach, which has been intensively explored recently, brings synthetic methods of polymer chemistry closer to the light-induced processes of macromolecular synthesis occurring in living organisms. Examples are given of practical application of CRP techniques to obtain industrially valuable, high-tech polymeric products. The bibliography includes 429 references.

Polysiloxane based on N-2-hydroxy-1,1-di(hydroxymethyl)ethyl-N’-3-triethoxysilylpropylurea was synthesized. The polymer forms small nanoparticles and their associates in water. The latter can retain poorly soluble luminophore and hydrophobic gadolinium complex. The doped particles are capable of interacting with proteins. Aqueous suspensions based on non-toxic siloxane nanoparticles can be used for visualization of results of assays of biological objects (bioimaging) by fluorescence and magnetic resonance tomography.

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.

Ruthenium(ii) and (iii) carborane complexes containing XantPhos as a ligand were synthesized for the first time. It was shown that the reaction of the known complex exo-5,6,10-[Cl(Ph3P)2Ru]-5,6,10-(µ-H)3-10-H-nido-7,8-C2B9H8 with a 10% molar excess of XantPhos in benzene at 80 °C leads to a new closo-ruthenacarborane 3-Cl-3,3-[x2-XantPhos]-closo-3,1,2-RuC2B9H11, which can be easily converted to the corresponding acetonitrile complex 3-CH3CN-3,3-[x2-XantPhos]-closo-3,1,2-RuC2B9H11 by the reaction with isopropylamine in a dichloromethane—acetonitrile solvent mixture at 40 °C. These compounds, as well as previously synthesized ruthenium(ii) carborane complexes, were used as a basis for new catalyst systems allowing to conduct controlled radical polymerization at high rates even at low catalyst loading. The specific features of methyl methacrylate polymerization under the action of the indicated catalyst systems were considered and the mechanism of the process was investigated.

Controlled polymerization of styrene (both self-initiated and initiated with azobisisobutyronitrile) in the presence of Blatter’s radical at 125 °C was studied. When using the radical initiator, there is no induction period. On the basis of UV spectroscopy and MALDI massspectrometry studies, it was established that the Blatter radical is completely consumed at the initial stage of the polymerization, inserting into almost all macromolecules. The prepared polystyrene exhibits the ability to reinitialization in post-polymerization and the synthesis of block copolymers.

We report a reversible-deactivation radical copolymerization of styrene and methyl acrylate in the presence of tributylborane and different p-quinones. p-Quinones, such as 1,4-naphthoquinone, 2,3-dimethyl-1,4-benzoquinone, 2,5-ditert-1,4-butylbenzoquinone, and duroquinone, with addition of a catalytic amount of tributylborane, allow for the control over styrene/methyl acrylate copolymerization. The process proceeds in a controlled manner via a reversible homolytic dissociation of the active macromolecules with terminal aryloxyboron-groups. The rate of styrene/methyl acrylate copolymerization depends on the inhibition constants of quinones. The molecular weight and molecular weight distribution of copolymers are directly dependent on the inhibitory abilities of the quinones. 1,4-Naphthoquinone and 2,3-dimethyl-1,4-benzoquinone act as the most effective mediators of chain propagation. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) results showed that the macromolecules contained internal fragments of p-quinone. Also, of the terminal aryloxyboron-groups were detected in the mass spectra. On realization of the “living” mechanism of copolymerization, the structure of copolymers obtained at high conversions can be considered as similar to the gradient structure. Stereo-regularity of the copolymers differed from the conventional radical copolymerization. The glass-transition temperature (Tg) of the gradient copolymer differed from Tg of the random compositional heterogeneous copolymer. The effect of the macromolecular structure on the mechanical properties of the copolymers was studied.

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 effect of methyl substituents in the lower belt of dicarbollide ligands on the redox potential of ruthenacarboranes based thereof, as well as the ability of the metallacarboranes obtained to catalyze radical polymerization with atom transfer were studied. For this purpose, a new approach to the synthesis of closo-ruthenacarboranes based on substituted dicarbollide ligands was developed and six new complexes 3,3-(Ph2P(CH2)4PPh2)-3-H-3-Cl-9-Me-12-X-closo-3,1,2-RuC2B9H9, 3,3,8-(Ph2P(CH2)4PPh-μ-(C6H4-o))-3-Cl-9-Me-12-X-closo-3,1,2-RuC2B9H8 and 3,3,4,8-(Ph2P(CH2)4P-μ-(C6H4-o)2)-3-Cl-9-Me-9-X-closo-3,1,2-RuC2B9H7 (X = H, Me) were synthetized and characterized by single crystal X-ray diffraction, NMR and ESR spectroscopy and MALDI TOF mass-spectrometry. Comparison of the values of the redox potentials of the synthesized ruthenium complexes in 1,2-dichloroethane with the values previously found for the corresponding ruthenacarboranes based on the parent dicarbollide anion showed that the introduction of methyl substituents into the carborane cage led to a decrease in the redox potentials of the complexes, which made them more preferable catalysts for ATRP. Test experiments on the polymerization of MMA showed that the synthesized ruthenacarboranes were effective catalysts for ATRP, the most active being the complex with two methyl groups and two ortho-phenylenecycloboronated fragments.

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 interaction of 3,3-(Ph2P(CH2)4PPh2)-3-H-3-Cl-closo-3,1,2-RuC2B9H11 (1) with isopropylamine and corresponding nitrile (NCR) in dichloromethane at 40 °C yields carborane clusters of Ru(II) with nitrile ligand [3,3-(Ph2P(CH2)4PPh2)-3-NCR-closo-3,1,2-RuC2B9H11] (R = –Ph, –CH=CH2). A similar ortho-cycloboronated clusters [3-NCR-3,3,8-{(Ph2P(CH2)4PPh-μ-(C6H4-ortho)}closo-3,1,2-RuC2B9H10] were obtained from the corresponding chlorine-containing ruthenacarboranes. The novel clusters were isolated as yellow crystal solids and characterized by NMR, mass-spectroscopy and X-ray analysis. The reaction of the obtained clusters with HCl showed the chemical reversibility of dehydrohalogenation. The performed electrochemical investigation testified the ability of novel complexes to undergo reversible oxidation to Ru(III) species.

A closo-metallacarborane complex of ruthenium(ii), 3,3,3-(Ph2P)3CH-closo-3,1,2-Ru-C2B9H11, is synthesized and structurally characterized. It is the first example of the metallacarborane clusters with chelate tridentate phosphine ligands. Quantum chemical calculations were carried out to evaluate the possibility of dissociation of one of the Ru-P bonds in this molecule with formation of reactive 16-electron species. According to the cyclic voltammetry study, the complex undergoes irreversible oxidation.

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.

In order to obtain molecular Ce(III) complexes which emit red light by f–d transitions the azolyl-substituted thiophenolates were used as the ligands. The thiophenolate Ce(III) complexes were synthesized by the reaction of Ce[N(SiMe3)2]3 with respective thiophenols 2-(2′-mercaptophenyl)benzimidazole (H(NSN)), 2-(2′-mercaptophenyl)benzoxazole (H(OSN)) and 2-(2′-mercaptophenyl)benzothiazole (H(SSN)) in DME media. The structures of the benzimidazolate (Ce(NSN)3(DME)) and benzothiazolate (Ce(SSN)3(DME)) derivatives were determined by X-ray analysis which revealed that the cerium ion in the molecules is coordinated by one DME and three anionic thiophenolate ligands. The lanthanum complex La(OSN)3(DME) has been synthesized similarly and structurally characterized. It was found that the solids of Ce(SSN)3(DME) and Ce(OSN)3(DME) exhibit a broad band photoluminescence peaking at 620 nm which disappears upon solvatation. With an example of OSN derivatives it was proposed that this behaviour is caused by the blue shift of the f–d transition of Ce3+ ions.

A (series) range of potential dimorpholinoquinazoline-based inhibitors of the PI3K/Akt/mTOR cascade was synthesized. Several compounds exhibited cytotoxicity towards a panel of cancer cell lines in the low and sub-micromolar range. Compound 7c with the highest activity and moderate selectivity towards MCF7 cells which express the mutant type of PI3K was also tested for the ability to inhibit PI3K-(signaling pathway) downstream effectors and associated proteins. Compound 7c inhibited the phosphorylation of Akt, mTOR, and S6K at 125–250 nM. It also triggered PARP1 cleavage, ROS production, and cell death via several mechanisms. Inhibition of PI3Kα was observed at a concentration of 7b 50 µM and of 7c 500 µM and higher, that can indicate minority PI3Kα as a target among other kinases in the titled cascade for 7c. In vivo studies demonstrated an inhibition of tumor growth in the colorectal tumor model. According to the docking studies, the replacement of the triazine core in gedatolisib (8) by a quinazoline fragment, and incorporation of a (hetero)aromatic unit connected with the carbamide group via a flexible spacer, can result in more selective inhibition of the PI3Kα isoform.

In the search for a way to organic up-converter materials the complex [(OON)2Er(THF)](μ-O)[(OON)2Yb(THF)] with the (benzoxazol-2-yl)phenolate (OON) ligand was synthesized. Upon excitation by laser with λex 405 nm light the complex displayed only emission of the Yb3+ ion indicating the lack of energy transfer from Yb to Er. To develop a method for preparation of other up-converter materials the complexes [Yb4(SON)8(μ4-O)(OH)2 and [Eu4(OON)10Li2(3-O)2] with (benzothiazol-2-yl)phenolate (SON) and (benzoxazol-2-yl)phenolate ligands were synthesized using water as a co-reagent. The X-ray study revealed that the clusters contain μ2-O, μ3-O and μ4-O bridges and short Ln…Ln contacts. These modelling syntheses showed that the method is applicable for preparation of potential up-convertion materials with Ln-O-Ln’ groupings.

A novel method for synthesis of diamagnetic Ru(II) carborane clusters based on reduction of corresponding Ru(III) species by amines was developed. The interaction of paramagnetic 17-electron complex (1) with aliphatic amines in dichloromethane solution at 40 °C proceeds with the abstraction of chlorine atom from the ruthenium center and results in formation of corresponding 16-electron species. The latter can be stabilized by 2-electron ligands such as triphenylphosphine or acetonitrile through the formation of novel stable complexes of ruthenium (II): (2: L = PPh3; 4: L = CH3CN). A bis(ortho-phenylene)cycloboronated complex (6) may be obtained in a similar way from corresponding precursor. The related reaction conducted with diamagnetic closo-carborane cluster of ruthenium (IV) 3,3-Ph2P(CH2)4PPh2-3-H-3-Cl-closo-3,1,2-RuC2B9H11] (7) gives 3-CH3CN-3,3-Ph2P(CH2)4PPh2-closo-3,1,2-RuC2B9H11] (8). The obtained complexes were characterized by means of NMR and IR spectroscopy and mass spectrometry. A single-crystal X-ray diffraction study confirmed closo-structure of the obtained complexes and the presence of acetonitrile molecule as a ligand. The performed electrochemical investigation of the obtained ruthenacarboranes testified its ability to undergo reversible oxidation to Ru(III) species. The comparison of the properties of the obtained complex 2 with its analogue with shorter alkyl fragment in diphosphine moiety shows that the slight difference in the structure leads to the decrease of stability.

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.

A novel type of copper-based regulating agents was first applied in radical polymerization of methyl methacrylate and acrylonitrile. It was shown that systems based on copper complex with redox-active bis(acetonaphthene) ligand (dpp-BIAN↔CuCl)2, carbon tetrachloride and different activating agents such as ascorbic acid or amines (tert-butylamine, diethylamine, triethylamine and pyridine) were capable to initiate polymerization of the above monomers in wide temperature range from 25 to 110 °C. The amine structure and basicity were found to make great impact on polymerization and molecular weight parameters of the obtained products. The systems developed are capable of conducting polymerization up to high monomer conversions in a wide temperature range leading to polymers with rather low molecular weight and moderate polydispersity. The most efficient system in terms of controlling the molecular weight characteristics of poly(methyl methacrylate) among others is the system based on (dpp-BIAN↔CuCl)2 and diethylamine, which makes it possible to obtain polymer with a polydispersity index of 1.36–1.60. In case of acrylonitrile polymerization, the highest polymer yield is achieved using a copper complex and triethylamine. The results of MALDI TOF mass spectroscopy measurements showed the presence of chlorine atoms at the chain ends of macromolecules. The formation of “living” chains during polymerization of methyl methacrylate was confirmed by the synthesis of block-copolymers with styrene.

In order to obtain new NIR luminescent lanthanide complexes free of C-H and C-O bonds the perfluorinated 2-mercaptobenzothiazolate (mbtF) was used as organosulphide antenna ligand and the perfluorinated triphenylphosphine oxide (TPPOF) was used to saturate the coordination sphere of the lanthanide ion. Targeted complexes Ln(mbtF)3(TPPOF)2 (Ln = Nd(1), Er(2) and Yb(3)) were synthesized in high yields from respective silylamides Ln[N(SiMe3)2]3, HmbtF and TPPOF using dry toluene as a solvent. Upon near UV light excitation the compounds 1–3 in the solid state showed an intense NIR photoluminescence which is characteristic for corresponding lanthanide ions. This luminescence was studied at a room temperature by time-resolved methods. The study revealed the presence of intermediate f-f transitions in the time resolved photoluminescence spectrum of 2. The measured lifetimes of Nd and Er NIR emission in 1 and 2 are 39.5 and 53.5 μs respectively. It was found that these lifetimes are among the longest for neat erbium and neodymium complexes with organic ligands.

Anovel facile way of synthesis of closo-ruthenacarboranes with chelate 1,2-bis(diphenylphosphino)ethane (dppe) with high yields was proposed. It was found that the interaction of the three-bridged 5,6,10-{Cl(Ph3P)2Ru}-[5,6,10-(μ-H)3-10-H-exo-nido-7,8-C2B9H10] (1) with dppe in acetonitrile or CH2Cl2/acetonitrile mixture leads to the formation of novel diamagnetic ruthenacarborane cluster 3-СNMe-3,3-[κ2-dppe]-closo-3,1,2-RuC2B9H11 (2) along with some amount of ionic compound [trans-(CH3CN)RuCl(dppe)2]+[C2B9H12]− (3) which may be also converted to 2 increasing its total yield. The reaction of 2 bearing divalent ruthenium with carbon tetrachloride or HCl gives the known 17-electron paramagnetic complex 3-Сl-3,3-[κ2-dppe]-closo-3,1,2-RuC2B9H11 (4)..The detailed investigation of the previously described method of synthesis of 4 from 3-H-3Cl-3,3-(PPh3)2-closo-3,1,2-RuC2B9H11 (5) allowed us to characterize the forming by-products as 3-PPh3-3,3,8-(Ph2P(CH2)2PPh-μ-(C6[H4-о)-closo-3,1,2-RuC2B9]H10 (6) and 3-[κ1-dppe]-3,3-[κ2-dppe]-closo-3,1,2-RuC2B9H11 (7). The obtained ruthenacarborane clusters undergo reversible Ru(II)/Ru(III) transition. It was shown that the complexes 2, 4 and 6 show good activity as catalysts for Atom Transfer Radical Polymerization of methyl methacrylate.

A set of new heterometallic complexes of composition of ErYb(L) 6 and Er 0.67 Yb 1.33 (L) 6 (L = 3-(2-benzothiazol-2-yl)-2-naphtholate (NpSON), pentafluorophenolate (C 6 F 5 O) and hexafluoro-iso-propoxide ((CF 3 ) 2 CHO) were synthesized and characterized by X-ray diffraction (L= (CF 3 ) 2 CHO), MALDI-TOF, 19 F NMR (L= C 6 F 5 O, (CF 3 ) 2 CHO), IR and elemental analyses. All the compounds exhibited emission of Er 3+ at 1530 nm upon direct excitation of Yb 3 + by the laser irradiation with λ ex = 910 and 980 nm that shows the intramolecular energy transfer Yb 3+ →Er 3+ . In the luminescence spectra of Er 0.67 Yb 1.33 [(CF 3 ) 2 CHO] 9 besides the band at 1530 nm the short-wavelength emission at 550 nm was found, which indicates upconversion phenomenon. Excitation of ytterbium in the mixture of monometallic iso -propoxides Er 2 [(CF 3 ) 2 CHO] 6 and Yb 2 [(CF 3 ) 2 CHO] 6 does not lead to luminescence of erbium ions which confirms intramolecular character of energy transfer in Er 0.67 Yb 1.33 [(CF 3 ) 2 CHO] 6 .

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.

A square-planar bis-o-semiquinonato nickel complex interacts with N,N'-disubstituted 1,4-diazabutadienes-1,3 forming six-coordinate compounds. The X-ray structural study indicates complex geometry to be close to the octahedral. Magnetic properties are determined by metal-ligand ferromagnetic exchange interactions which are promoted by complex geometry. In polar solvents (THF, CH2Cl2, and CHCl3) complexes are partly dissociated into corresponding diazabutadiene-nickel catecholate and free o-quinone. In the case of the most sterically hindered 1,4-bis-(2,6-di-iso-propylphenyl)-2,3-dimethyl-1,4-diazabutadiene-1,3 in n-hexane or toluene the above-mentioned reaction is accompanied by the coupling through the back-bonded methyl groups of diazabutadiene. The organic product of the coupling was eliminated from the complex, isolated and structurally characterized. Taking into account the quantitative yield the coupling reaction is the actual procedure for the synthesis of new potential nitrogen ligands.

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.

Heterometallic complexes Ln(L1)5Zn (Ln = Sc, Sm, Gd) were obtained by the reactions of silylamides Ln[N(SiMe)2]3 with 2-(benzoxazol-2-yl)phenol (HL1) in the presence of diethylzinc. Similar reactions with 3-(benzothiazol-2-yl)-2-naphthol (HL2) led to the formation of complexes Ln(L2)5Zn (Ln = Nd, Er, Gd, Yb). The introduction of the zinc-containing fragments provided a considerable increase of photo- and electroluminescence intensity of the scandium complex.

The first example of 12-vertex metallapolyhedra, namely, tris-phosphorus-containing closo-metallacarborane ruthenium(II) cluster , was synthesized and structurally studied. A principal possibility of the use of aliphatic amines as one-electron reducing agents converting carborane ruthenium(III) complexes to structurally close ruthenium(II) compounds was experimentally demonstrated.

Three novel binuclear high spin cobalt(II) complexes containing two bis(o-semiquinonato)cobalt fragments bridged by tetradentate N-donor ligand (1,2-bis(pyridin-2-ylmethylene)hydrazine) were synthesized. The complexes differ one from another by substituents in the o-semiquinonato ligands. The obtained complexes were characterized by IR-spectroscopy and variable temperature magnetic susceptibility measurements. Crystalline and molecular structures of complex bearing the anion-radical of 4,5-(N,N′-piperazino)-3,6-di-tert-butyl-o-quinone was established by X-ray structural analysis. According to obtained magnetic data all complexes demonstrate antiferromagnetic ligand–ligand, metal–ligand and metal–metal exchange interactions.

Alkoxides [Ln(OR)3(DME)]2 (R = CH(CF3)2, Ln = Sm (1), Yb (2)), [Ce(OR)3(Phen)]2 (3) (Phen = 1,10-phenanthroline), [Ce(OR′)3(DME)2]2 (R′ = C(CF3)3) (4), {Gd(OR′)3(DME)2} (5), {Ln2[O(CF3)2C–C(CF3)2O]3} (Ln = Ce (6), Gd (7)), {Ce2[O(CF3)2C–C(CF3)2O]3(Phen)2} (8), and {Ce[O(CF3)2C–C(CF3)2O][O(CF3)2–C(CF3)2OH](Phen)2} (9) were synthesized by the reactions of silylamides Ln[N(SiMe3)2]3 with respective fluorinated alcohols. The heterovalent trinuclear complex {Sm2(μ2-OR)3(μ3-OR)2Sm(OR)2(THF)2.5(Et2O)0.5} (10) was obtained by treatment of SmI2(THF)2 with ROK. The reaction of europium(II) and yttrium(III) silylamides with ROH afforded the heterobimetallic alkoxide {Eu2(μ2-OR)3(μ3-OR)2Y(OR)2(DME)2} (11) containing divalent europium. The molecular structures of 1, 2, 3, 9, 10 and 11 were determined by X-ray analysis. All the prepared cerium derivatives as well as the europium–yttrium isopropoxide upon UV excitation exhibited photoluminescence in the regions of 370–425 (for Ce3+) and 485 nm (for Eu2+) which was assigned to 4d→5f transitions.

Novel complexes of ruthenium with tridentate phosphine ligands: tris(diphenylphosphinomethyl)ethane and bis(2-diphenylphosphinoethyl)phenylphosphine were synthethised starting from the well-known exo-nido-ruthenacarborane [exo-5,6,10-{Ru(Ph3P)2Cl}-5,6,10-(μ-H)3-10-H-nido-7,8-C2B9H8] via ligand substitution followed by exo-nido- to closo-rearrangement in toluene. The novel compounds were characterized by NMR or EPR spectrometry, MALDI TOF mass-spectrometry and cyclic voltammetry. A single-crystal X-ray diffraction study confirmed closo-structure of the obtained complexes and the presence of η3-coordinated triphosphine ligands in it structures. The correlations between ligand structure and complex stability and reactivity were established. The possibility of application of ruthenacarboranes with tridentate phosphine ligands in Atom Transfer Radical Polymerization (ATRP) was explored. It was found out that complexes based on tris(diphenylphosphino)methane are the most suitable catalysts.

The peculiarities of controlled copolymerization of acrylonitrile with methyl acrylate and dimethyl itaconate in the presence of copper-based catalytic system were investigated. It was shown that the polymerization proceeds in a controlled mode in accordance with ARGET ATRP mechanism. The increase of molecular weights in a strict agreement with theoretically predicted values is observed. The formation of copolymers was confirmed by NMR and MALDI TOF MS analysis. The introduction of mentioned monomers to acrylonitrile results in slight decrease of the polymerization rate. The performed calorimetric investigations showed the smoothing of exothermic effect of the oxidative stabilization of formed copolymers.

This chapter is devoted to the observation of general methods of polymer synthesis including radical, ionic, coordination, and metathesis polymerization. The main advantages, possibilities, and drawbacks of each method are discussed. A special emphasis was placed to the modern methods of controlled polymer synthesis leading to well-defined polymers with desired structure, composition and properties. Such methods are considered as a way to the novel polymer materials for various high-tech applications.

Using polymerization of a series of acrylic monomers of various structure in the presence of ruthenium complexes as an example, it was shown that introduction of amines into the polymerization system allows to overcome one of the significant drawbacks of the controlled polymer synthesis under the radical initiation conditions, connected with the low rate of the polymerization. The influence of the amine nature on the peculiarities of the controlled polymer synthesis in the presence of ruthenacarboranes has been studied and amine was found to act as a reducing agent converting ruthenium in a complex to the lowest oxidation state and regenerating the true polymerization catalyst.

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.

A set of Y, Nd, Tm and Yb complexes containing, along with 3-(2-benzothiazol-2-yl)-2-naphtholate (L), the 8-oxyquinolate (Q), pentafluorophenolate, cyclopentadienyl (Cp) or methylcyclopentadienyl (CpMe) ligands were synthesized using Ln[N(SiMe3)2]3, Ln(Cp)3 or Ln(CpMe)3 as starting materials. Depending on molar ratio of initial reagents the mononuclear, dinuclear or tetranuclear products were isolated from the reaction mixtures. The complexes Y2(L)4(CpMe)2, Nd2(L)4(Cp)2, Yb(L)(Cp)2, Y2(L)3(Q)2(CpMe) and Y4(L)(Q)11 were structurally characterized. The synthesis routes and conditions governing the set of ligands in products and their nuclearity are discussed.

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.

A new water-soluble conjugate, consisting of a chlorin-based photosensitizing part, and a 4-arylaminoquinazoline moiety with high potential affinity to an epidermal growth factor receptors (EGFR) and vascular endothelial growth factor receptors (VEGFR), suitable for photodynamic therapy (PDT), was synthesized starting from methylpheophorbide-a in seven steps. An increased accumulation of this compound in A431 cells with high level of EGFR expression, in comparison with CHO and HeLa cells with low EGFR expression was observed. The prepared conjugate exhibits dark and photoinduced cytotoxicity at micromolar concentrations with IC50dark/IC50light ratio of 11–18. In tumor-bearing mice, the conjugate preferentially accumulates in the tumor tissue.

To obtain luminescent lanthanide complexes with a low energy LMCT state the 2-(2'-mercaptophenyl)benzothiazolates, Ln(SSN)3, and 2-(2'-mercaptophenyl)benzoxazolates, Ln2(OSN)6 (Ln = Gd, Yb), were synthesized by the reaction of amides Ln[N(SiMe3)2]3 with respective thiophenols. Ytterbium complexes were structurally characterized by X-ray diffraction analysis. Cyclic voltammetry revealed that the deprotonated mercaptophenyl ligands have significantly lower oxidation potentials than their phenoxy analogues and some β-diketones. The photophysical properties of Gd and Yb compounds were studied both in solution and in the solid state. The fluorescence spectra of the compounds in solution display the bands of the keto and enol forms of the ligands. No energy transfer from the organic part to Yb3+ has been detected in solutions of both Yb complexes, whereas in solids an intense metal-centered emission in the near infrared region was observed. The solid Gd compounds exhibited room temperature phosphorescence caused by unusually efficient intersystem crossing facilitated by the essentially reducing properties of OSN and SSN ligands. To explain the sensitization process occurring in solids Yb2(OSN)6 and Yb(SSN)3 a specific non-resonant energy transfer mechanism via a ligand to metal charge transfer state has been proposed. Based on the Yb derivatives, NIR-emitting OLEDs with 860 μW cm-2 maximal irradiance were obtained. Their Gd counterparts showed bright electrophosphorescence (up to 1350 cd m-2) in the devices containing doped emission layers.