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The coordination diversity of a novel N4-ligand and its sodium complex toward cobalt(ii) ions was studied.

The development of efficient methods for preconcentration and purification of petroleum metal porphyrins is the necessary condition for further progress of basic and especially applied research concerning the properties of these compounds and their role in oil genesis and maturation. This study deals with chromatographic preparation of high-purity vanadyl porphyrins using a sulfuric acid cation exchanger that can be readily prepared from silica gel and sulfuric acid and is simple in use. At the silica gel : sulfuric acid : water weight ratio of 60 : 15 : 25, the suggested sulfuric acid cation exchanger retains most efficiently nonporphyrin impurities of the asphaltene polar extract, whereas a significant fraction of vanadyl porphyrins (up to ~50%) passes through the chromatographic column virtually without retention with the stationary phase. In contrast to traditional adsorbents, the suggested sulfuric acid cation exchanger allows preparation of spectrally pure vanadyl porphyrins in one chromatographic purification step, thus ensuring the minimal consumption of the eluent and adsorbent. High purity of the vanadyl porphyrins obtained was confirmed by mass-spectrometric and spectroscopic methods of analysis.

In well stimulation treatments using hydrochloric acid, undesirable water-in-oil emulsion and acid sludge may produce and then cause operational problems in oil field development. The processes intensify in the presence of Fe(III), which are from the corroded surfaces of field equipment and/or iron-bearing minerals of the oil reservoir. In order to understand the reasons of the stability of acid emulsions, acid emulsions were prepared by mixing crude oil emulsion with 15% hydrochloric acid solutions with and without Fe(III) and then separated into free and upper (water free) and intermediate (with water) layers. It is assumed that the oil phase of the free and upper layers contains the compounds which do not participate in the formation of acid emulsions, and the oil phase of the intermediate layers contains components involved in the formation of oil/acid interface. The composition of the oil phase of each layer of the emulsions was studied. It is found that the asphaltenes with a high content of sulfur, oxygen and metals as well the flocculated material of protonated non-polar oil components are concentrated at the oil/acid interface. In addition to the above, in the presence of Fe(III) the Fe(III)-based complexes with polar groups of asphaltenes are formed at the acid/oil interface, contributing to the formation of armor films which enhance the emulsion stability.

The reaction of (R)-1-(1-phenyl)ethyl-3-(O,O-diethylthiophosphoryl)thiourea with Cu(II) acetate is accompanied by copper reduction and leads to the formation of a chiral polynuclear Cu6L6 complex. In the crystalline phase the complex consists of six Cu(I) ions alternating with sulfur atoms in the central core, with all six ligands exhibiting similar 1,5-S,S-coordination modes. This structural multinuclear arrangement is preserved in solutions, while at the same time partial disproportionation is observed with the formation of complexes of lower dimensionality. Synchronous redox processes are observed for all six copper ions in the complex in the solid state. The mechanism of copper reduction with the ligand itself as a reducing agent is proposed.

The effect of the natural minerals pyrite and hematite as a catalyst on the efficiency in destruction of the organic matter of Domanik rock, rich in organic matter, at a temperature of 300°C in a steam–carbon dioxide gas environment has been studied. Compared with the original rock and a control experiment, the presence of the natural catalysts in the reaction system leads to an increase in both the amount of mobile hydrocarbons in the rock and the yield of extracts, in which the concentration of saturated hydrocarbons is increased by factors of 12 and 16 in the experiments with pyrite and hematite, respectively, and the asphaltene content is halved. The degradation processes of high-molecular-weight resinous–asphaltenic components and insoluble kerogen lead to the formation of lower n-alkanes and the structuring of asphaltenes to increase the degree of their carbonization, followed by the formation of insoluble substances of the carbene–carboid type appearing as a new dispersed solid phase in the products. The distinctive features of the structural composition of asphaltenes and carbenes–carboids have been revealed. The close composition of the products of hydrothermal–catalytic experiments suggests that pyrite and hematite exhibit similar catalytic properties under hydrothermal conditions.

The electrochemical reduction of cobalt dibromide 2,2′-bipyridine (bpy) complexes (Co/bpy molar ratio 1:1) results in the formation of cobalt nanoparticles (CoNP) formed by the disproportionation reaction of the electrochemically generated cobalt(I) mononuclear complexes. The process of the electrochemical generation of CoNP was monitored by in situ EPR-spectroelectrochemistry where the signals of the ferromagnetic resonance (FMR) have been observed for these species. According to small-angle X-ray scattering (SAXS) analysis the average diameter and the average length of the formed cylindrical CoNP is varied from 9 to 10 nm and 30–32 nm, respectively, and correlates to the g-value and the broadness of the FMR signal observed by in situ EPR-spectroelectrochemistry during electrochemical process.

Membrane-electrode assemblies (MEA) with a cathode catalyst made of a nickel sodium pectate complex PG-NaNi with a 25% substitution of sodium for nickel, and with a commercial anode catalyst made of platinum black have been successfully created. Tests in a H2/O2 proton exchange membrane fuel cell (PEMFC) yielded the values of the maximum current density of 59 mA cm−2 and the maximum power density of 5.9 mW cm−2. These results permit the development of environmentally friendly and stable cathode catalysts for PEMFCs made of a readily available biological raw material, pectin.

Using the atomic absorption spectrometry and electronic paramagnetic resonance techniques, we have investigated the features of vanadium and vanadyl complexes content in asphaltenes of heavy oils o...

Comparative analysis of thermal analysis and EPR spectroscopy data on asphaltenes from Ashal’chinskoe and Mordovo-Karmal’skoe bitumens recovered by steam drive and in situ combustion has been performed. It has been found that the steam drive does not alter the structural-group composition of asphaltenes whereas the in situ combustion lead to conversion of asphaltenes into coke-like particles deposited onto the rock surface in the reservoir. It has been shown that the asphaltenes with a high proportion of condensed aromatic entities are carriers of genetic information on the petroleum system.

Nickel (I) complexes of 1,5-diaza-3,7-diphosphacyclooctane PPh2NR2 ligands were obtained from precursor Ni(II) by exhaustive electrolysis of [Ni(PPh2NR2)2]2+ precursors at the Ni(II/I) couple potential and characterized by several techniques. Paramagnetic Ni(I) complexes were investigated by cyclic voltammetry, spectroelectrochemistry UV/Vis and ESR methods at room temperature and in a frozen solution. Catalytic behavior of Ni(I) complex in different ligand environment for hydrogen evolution from acid depends from the ligand nature. The two possible catalytic cycles were proposed depending on the nitrogen substituents in 1,5-diaza-3,7-diphosphacyclooctane.

In this article, we report the synthesis of mono- and bimetallic Pd–Ni nanocomposites supported on a multicharged polymeric matrix for catalytic applications. The morphology and catalytic properties of the composites depend on the Pd–Ni ratio. In the Suzuki–Miyaura coupling reaction, the composite with an equal amount of palladium and nickel is the most active and the reaction occurs within six hours in water at room temperature.

New nickel-based complexes of 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-bian) with BF4 - counterion or halide co-ligands were synthesized in THF and MeCN. The nickel(I) complexes were obtained by using two approaches: 1) electrochemical reduction of the corresponding nickel(II) precursors; and 2) a chemical comproportionation reaction. The structural features and redox properties of these complexes were investigated by using single-crystal X-ray diffraction (XRD), cyclic voltammetry (CV), and electron paramagnetic resonance (EPR) and UV/Vis spectroscopy. The influence of temperature and solvent on the structure of the nickel(I) complexes was studied in detail, and an uncommon reversible solvent-induced monomer/dimer transformation was observed. In the case of the fluoride complex, the unpaired electron was found to be localized on the dpp-bian ligand, whereas all of the other nickel complexes contained neutral dpp-bian moieties.

The newly prepared unsymmetrical pincer ligand with a benzothiazole side-arm 2-(3-((di-tert-butylphosphino)methyl)phenoxy)benzo[d]thiazole [BzTz(H)PCN] has been reacted with anhydrous NiBr2 to get the corresponding NiII square planar bromo complex (BzTzPCN)NiBr (1) after HBr elimination and C H activation on the pincer central phenyl ring. Starting from 1, reaction with AgF in toluene or with AgBF4 in THF led to bromide abstraction and formation of the fluoro complex (BzTzPCN)NiF (2) and the ionic aquo species [(BzTzPCN)Ni(H2O)]BF4 (3), respectively. All species have been characterized in solution (multinuclear 1H, 13C{1H}, 31P{1H} and 11B NMR spectroscopy) and in the solid state (single-crystal X-ray diffraction analysis). Finally, comparative electrochemical measurements (CV and in situ EPR-spectroelectrochemistry) carried out on the halide complexes 1 and 2 revealed that the anodic oxidation process leads to the formation of stable NiIII species bearing a coordinated bromide ligand in case of 1 and a fluoride-free complex in case of 2.

The work introduces a synthesis of novel amphiphilic p-tert-butylphenol derivatives with the polyethyleneoxide and biodegradable ionogenic polyethylenecarbonate moieties. The dependence of their aggregation behaviour on the lengths of polyethyleneoxide and polyethylenecarbonate chains indicates the impact of the hydrophilic moieties and ionogenic end-groups in the aggregation behaviour of the amphiphiles. The micelles of the amphiphiles are negatively charged, although neither pH nor counter ions (exemplified by Gd(III) ions) affects the values of their critical micelle concentrations. The presence of the ionogenic end-groups is the main reason of the pH and concentration dependent extraction of Gd(III) ions from the neutral (pH 6.2-7.2) aqueous solutions of the amphiphiles through their phase separation at room temperatures. The extraction regularities point on the stoichiometric binding of the amphiphilic molecules with Gd(III) ions as the main reason of the phase separation in their aqueous solutions. Nevertheless the micellization of the amphiphiles is responsible for the peculiar concentration effect on the extraction of Gd(III) ions from the aqueous solutions.

Based on ferrocene-1,1'-diyl-bisphosphinic acids Fc[P(R)(O)OH]2 (R = H, Me, Et, Ph) in methanol, two types of electrochemically driven molecular rotors are developed. Monoanions of acids are fixed in the cis-conformation due to the presence of an intramolecular hydrogen bond, whereas dianions are fixed in the trans-conformation due to electrostatic repulsion forces. Upon the transformation of monoanions to dianions, the controlled rotation of cyclopentadienyl rings from cis to trans-conformation occurs; the reverse switching leads to the reverse rotation. In one type of rotors, the rotation is controlled by the reversible variation of the solution pH and composition in the electrochemical oxidation-re-reduction cycle of N-phe-nyl-N'-isopropyl-1,4-phenylenediamine; in the other type, the rotation is determined by the one electron oxidation-re-reduction of the ferrocene nucleus in monoanions. The latter rotor type at room temperature can operate stably only for a short time (τ< 1 s) and at longer times is irreversibly destructed during the oxidation stage.

Electrochemical reduction of elemental (white) phosphorus in an undivided cell equipped with a sacrificial metal anode (Al, Co, Nb, Sn) results in the formation of the reduced form of white phosphorus, P4 2– dianion, which was detected in solution by 31P NMR spectroscopy.

The association and deposition of tetraviologen calix[4]resorcin MVCA-C58+ can be controlled using the electrochemical reduction-reoxidation cycle of viologen units. The monomeric MVCA-C58+was converted into the highly molecular (MVCA-C54+·)n associate (π-polymer) by reducing it to the MVCA-C54+· tetra(radical cation) and completely returns to the starting monomeric state by reverse oxidation. The reduction to the neutral state MVCA-C50 allowed calixresorcin to pass from solution to precipitate and the reverse oxidation led to its returning in solution.

Dialkyl(diaryl)-(2-methyl-4-oxopent-2-yl)phosphine oxide oximes have been synthesized for the first time. According to the X-ray diffraction data, these compounds in crystal exist as a single E isomer. Their structure in solution and the E/Z isomer ratio were determined by 1H and 13C NMR spectroscopy.

The organonickel complex [NiBr(Mes)(phen)] (1) (Mes = 2,4,6-trimethylphenyl, phen = 1,10-phenanthroline) was synthesized by oxidative addition of MesBr to nickel(0) complexes, obtained from [Ni(COD)2] (COD = 1,5-cyclooctadiene) and phen, or electrochemically generated from [NiBr2(phen)], and by ligand exchange reaction from [NiBr(Mes)(PPh3)2]. The electrochemical properties of [NiBr(Mes)(phen)] were investigated by cyclic voltammetry and in situ EPR spectroelectrochemistry. The cathodic reduction of 1 resulted in formation of the neutral radical complex [Ni(Mes)(phen −)] with a 1,10-phenanthroline radical anion bound to a nickel(II) centre. The electrochemical generation of the free 1,10-phenanthroline radical anion from 1,10-phenanthroline is also described.

The possibility of controlling the association of tetraviologen calix[4]resorcinol (MVCA-C5 8+) with 3,7-di(l-menthyl)-1,5-di(p-sulfonatophenyl)-1,5-diaza-3,7-diphosphacyclooctane (APCO-22−) in the electrochemical cycle of reduction-reoxidation of viologen units was shown. Reduction to tetra(radical cation) MVCA-C5 4+· transforms monomeric MVCA-C5 8+ and APCO-22- into the associate (π-polymer) (xAPCO-22−·yMVCA-C5 4+·) n , which is completely returned by reoxidation to the initial state.

Possibility of using the electron paramagnetic resonance method to study the antioxidant activity of structured colloid systems with active components: polymeric cosmetic gels, foaming detergents (shampoos), and lotions. It is shown that this versatile method opens up new opportunities for determination of the antioxidant activity not only in liquid-phase systems, but also in gels without any considerable disintegration of their structure. The antioxidant activity is affected by the concentration of additives, nature of an extract, and composition of formulation ingredients.

Ashal’chinskoe and Mordovo-Karmal’skoe crude oils and their components have been studied by thermal analysis and ESR spectroscopy. Directly from the oils as such, two sets of asphaltene fractions (I and II) have been obtained by the two-step addition of 40-fold excess of a precipitant with varying the oil: precipitant ratio in the first step to be 1 : 5, 1 : 10, and 1 : 20. A comprehensive analysis of the results of studying the oils and asphaltene fractions revealed specific features of aggregation of asphaltenes in different oils.

The present report is inspired by the idea to develop novel spectroscopy based techniques to detect the phase transitions in solutions of triblock copolymers with the use of Gd(III) and Eu(III) ions as probes. The choice of (PEO)13(PPO)30(PEO)13 (L64), (PPO)14(PEO)24(PPO)14 (17R4), (PPO)8(PEO)22(PPO)8 (10R5) and Triton X-100 is conditioned by their phase transitions occurring in mild conditions. The cloud point extraction (CPE) data reveal the conditions (pH and chelating agent) where the binding of lanthanides with surfactant rich phase of triblock copolymers and Triton X-100 occurs. The effect of phase transitions in solutions of triblock copolymers on the temperature resolved line widths in EPR spectra of Gd(III) aqua ions and transverse relaxation rates of Gd(III) inner-sphere water protons depends on the architecture of triblock copolymers and pH conditions. The steady state luminescence of Eu(III) complexes with phosphine oxide in aqueous solutions of triblock copolymers and TX-100 is influenced by the temperature induced aggregation and phase separation in solutions of reverse triblock copolymers 17R4 and 10R5, while the effect of the aggregation is insignificant for L64.

New nitrogen-containing derivatives of the diterpenoid isosteviol (16-oxo-ent-beyeran-19-oic acid) containing oxo, hydroxyimine, and thiosemicarbazone groups were synthesized. Isosteviol 15-oxo-16-thiosemicarbazone forms a 1: 1 complex with CuII and inhibits the growth of Mycobacterium tuberculosis (H37RV, in vitro) at the minimum inhibitory concentration of 20 μg mL−1.

Singularities of the rhodium trichloride reaction with calix[4]resorcinol functionalized with CH2N· (CH3)2 groups in ethanol on the upper rim of the molecule, and also of calix[4]resorcinol with ethanol solution of rhodium trichloride saturated with nitrogen monoxide were studied. Neutral complex compounds separated in the solid form were characterized by IR spectroscopy, Raman spectroscopy, 1H NMR, ESR, X-ray electron spectroscopy, electronic spectroscopy, and conductometry. Quantum-chemical calculations were performed on the basis of the density functional method in order to determine the geometric structure and energy characteristics of the complex compound and the zwitter-ion form of the ligand.

Electrooxidation of spatially hindered amines of the series of 2,2,6,6-tetramethylpiperidine in the medium of acetonitrile results in formation of radical cations, aminyl radicals, nitroxyl radicals, and oxoammonium salts identified using the methods of cyclic voltammetry and ESR spectroscopy.

Electrochemical oxidation of 1-haloamines of the 2,2,6,6-tetramethylpiperidine series results in the formation of relatively stable radical-cations, detected by the methods of cyclic voltammetry and ESR spectroscopy. The final products of electrochemical oxidation of these haloamines are stable nitroxyl radicals.

A supramolecular neutral complex was isolated in the solid state in the reaction of calix[4]-resorcinol having nitrogen-containing substituents [CH2N(CH3)2] on the upper rim of the molecule with RhCl3·3H2O in acetone. The complex, in addition to the calixarene structure and the rhodium-containing fragment, includes the dioxygen molecules bound to the rhodium ion [Rh+3(O2−)]. The compound was characterized by IR, Raman, 1H NMR, ESR and electron spectroscopy, and by conductivity. The composition was confirmed by elemental analysis, XRD study and derivatography. The electronic structure of the complex was revealed by analysis of electron spin resonance spectrum and electron absorption spectrum.

Asphaltenes derived from oxidized asphalts are separated into five fractions that differ in solubility. The amount of the low-molecular-mass fraction in the asphaltenes does not exceed 20%, and that of the high-molecular-mass fraction is above 50 wt %. The high and low-molecular-mass fractions of the asphaltenes are studied by EPR spectroscopy, thermal analysis, and calorimetry. It is found that the high molecularmass fraction of the asphaltenes is characterized by a high amount of condensed aromatic structures; it has a tendency to form mesophases with different thermal stability and is responsible for the formation of ordered structures in asphalt. It is revealed that an increase in the amount of the high molecular-mass fraction in asphaltenes of oxidized petroleum asphalts leads to a decrease in their stability, which has an adverse effect on the stability of physicochemical characteristics and quality of the commercial products. It should be noted that this dependence is more pronounced for structured asphalts.

Here, we report the first results of investigation the local structure and photoactive properties of iron-containing dendromesogens based on decyloxybenzoate substituted poly(propylene imine) dendrimers of the first to fifth generations. Iron ions existing in a high-spin state are coordinated in dendrimer ligands by two kinds of iron-complexing sites with an octahedral and a tetrahedral symmetry. Octahedral (high-symmetry) centers are located at the border of the dendrimeric core, while the tetrahedral centers with strong rhombic distortion of iron environment are distributed throughout all branching of the dendrimeric core. It has been found that all iron-containing dendromesogens exhibit light-harvesting and fluorescence properties.

The features of the reaction of rhodium trichloride with calix[4]resorcinols modified with various types of phosphorus-containing groups in ethanol, ethanol-formate medium and acetone under an inert atmosphere were studied. Neutral complexes were isolated in the solid form, the solvent molecules were shown to be actively involved into the formation of the final reaction products. The compounds were characterized by IR, Raman, 31P NMR, ESR, X-ray photoelectron and electronic spectroscopy, and electric conductivity. The composition was confirmed by the data of elemental analysis, X-ray fluorescence analysis, and derivatography. Based on the analysis of the ESR spectrum, the electronic and geometric structures of the paramagnetic product isolated from the acetone medium was determined.

Phenylindolizinylquinoxalinomonopodands, obtained by the reaction of 1-(phenylindolizin-2-yl)quinoxalin-2(1H)-one with corresponding dibromotrioxa- and dibromopentaoxaalkanes, undergo oxidative dehydrocyclization assisted by molecular iodine to yield new redox-active diindolizinadiquinoxalinacyclooxaalkaphanes. Using CVA, the indolizine fragments of the heterocyclophanes in acetonitrile are found to undergo three-step oxidation with transfer of one electron in each step. The first and the third steps are reversible, whereas the second is irreversible. The oxidation at potentials of the first peak leads to the stable radical cations registered by ESR (g = 2.0024, a2N = 0.26 mT).

Synthesis of water-soluble potassium salts of carboxymethyl derivatives of calix[4]pyrogallols and dodeca(carboxylatomethyl)tetramethylcalix[4]pyrogallol (L) complexes with transition metal ions (Cu2+, Fe3+, La3+) is described. Their structures in the solid state and in solution were characterized by NMR spectroscopy, ESR, and IR spectroscopy. Calix[4]pyrogallol dodecacarboxylates exist in the rccc-configuration. Calix[4]pyrogallol with methyl substituents at the lower rim in a wide range concentrations exists in water predominantly in the dimeric form. The obtained polynuclear transition metal complexes possess less symmetric structure than potassium salt of calix[4]pyrogallol (K12L). All studied complexes contain water molecules bound by rather strong hydrogen bonds. At room temperature the Fe4L complex is characterized by the environment of the Fe3+ ions close to octahedral. The absence of signals in the ESR spectrum of the Cu6L complex indicates the strong antiferromagnetic interaction Cu2+-Cu2+.

The features of the reaction between dirhodium(II) carboxylate and calix[4]resorcinarenes modified with various type functional groups at the upper and lower rim of the molecule in protic anhydrous solvent (ethanol) under inert atmosphere were investigated. Neutral complex compounds were isolated formed as a result of substitution of a water molecule by the macroligand in the axial position with respect to the R\( \tilde h \)Rh bond occurring with the conservation of the latter. The compounds were characterized by 31P NMR, UV, IR, Raman, and ESR spectroscopy. Their composition was confirmed by elemental analysis.

The oxidative dehydrocyclization of the 3-(indolizin-2′-yl)-2-oxoquinoxaline monopodand performed either electrochemically or under the action of molecular iodine affords new redox-active heterocyclophane consisting of the redox-switchable biindolizine fragment combined with the polyether-bridged π-deficient quinoxaline systems. The single-crystal X-ray diffraction study showed that the trioxaundecane chain of heterocyclophane adopts an extended conformation, and one of the phenyl substituents of the molecule closes the pseudocavity formed by the spacer from one of the sides. The cyclic voltammetric study of heterocyclophane in MeCN and DMF showed the three-step oxidation of the indolizine fragments accompanied by the single-electron transfer in each step. The first and third steps are reversible, and the second step is irreversible. The oxidation at potentials of the first peak gives rise to stable radical cations detected by the ESR method (g = 2.0024, a 2N = 0.26 mT).

Electrochemical oxidation of 1,11-bis(3-indolizinin-2-ylquinoxalin-2-on-1-yl)-3,6,9-trioxyundecane in 0.1 M Et4NClO4 in MeCN on a glassy-carbon electrode leads to surface films of two types depending on the film formation mode. Oxidation at controlled first-peak potentials (Ep1 = 0.30 V relative to Fc/Fc+) or in the range of potentials −0.60 → +0.40 → −0.60 V, −0.60 → +0.40 → −1.60 → −0.60 V in the polycycling mode forms a redox-active film that covers the entire surface of the electrode. The quinoxaline fragments of the film are reduced irreversibly in the supporting solution, while the indolizine fragments are reduced reversibly, forming stable radical cation states; the latter are recorded by ESR in the form of a singlet with a variable width (g = 2.0025, ΔH = 0.15−0.5 mT). The oxidized (radical cation) form of the film is conductive, while the neutral film is not. An insulating film is obtained when oxidation is performed under rigid conditions (−0.60 → +1.70 → −1.70 → −0.60 V). Both types of film are colored and have nanosized pores (channels), which can play a discriminant role. It is demonstrated (using the discriminant role of pores) that small molecules may be selectively reduced on film-coated electrodes in the presence of bulkier and more reactive substrates.

Complexes of copper(II) bromide with cyclic and isostructural acyclic phane ligands containing derivatives of pyrimidine nucleobases (cytosine and uracil) were synthesized and characterized. In two cyclic pyrimidinophanes used, the macrocycles included two 6-methylthiocytosine and one 6-methyluracil units linked by polymethylene chains (L3) and two 6-methyluracil units linked by N-containing bridges (L5). Ligand L3 and its isostructural acyclic analogs are coordinated by the Cu2+ ion through the same donor sites (the ring N atoms of the thiocytosine units). The coordination polyhedra of the Cu atom in complexes with cyclic and acyclic ligands are different. Ligand L5 and its isostructural acyclic analog also form copper(II) complexes with different coordination polyhedra involving different donor sites. The acyclic ligand is coordinated by the Cu2+ ion via the bridging N atom, while cyclic ligand L5, via the uracil CO groups (the bridging N atoms become protonated). The resulting complexes are dielectrics.

The electrochemical reduction of carbonyl-containing methanofullerenes is studied by methods of cyclic voltammetry and ESR with in situ electrolysis in the environment of 0.1 M Bu4NBF4 in o-dichlorobenzene-dimethylformamide (3:1 by volume). It is shown that the one-electron transfer onto the fullerene sphere of these compounds induces opening of the three-membered cycle, which leads to processes of retrocyclopropanation, transfer of the adduct onto the fullerene sphere of another molecule with the formation of bismethanofullerenes, and transformation into fullerodihydrofuran. The totality of competitive processes and the balance between these is defined by the nature of substituents at the exocarbon atom and the experimental conditions. The opening process is interpreted as the intramolecular electron transfer from the fullerene sphere onto the three-membered cycle.

The primary purpose of this study was to examine the effects of high-intensity acute exercise on neutrophil infiltration in different muscle fiber types of untrained rats and to compare postexercise neutrophil accumulation in muscles of untrained and trained animals. The effect of high-intensity acute exercise on blood neutrophil degranulation reaction in trained animals was also elucidated. Neutrophil enzyme myeloperoxidase (MPO) was determined as a measure of neutrophil migration into muscles and blood neutrophil degranulation. Male albino rats were subjected to acute exercise and 5 weeks of training. The used model of intensive acute exercise consisted of 5, 15, and 25 intermittent swimming bouts with the addition of weight (8% of total body mass) for 1-min each, followed by 1.5-min rest intervals. MPO was analyzed in quadriceps muscle (white and red portion) and in soleus muscle 24 h after acute exercise. MPO content in resting blood plasma and neutrophils was determined 48-h following the completion of a training process. In addition, MPO content in the trained rats was measured immediately (in blood plasma and neutrophils) after and 24 h (in muscles) following a single-bout of exercise to exhaustion. The remaining two-third of the trained animals were exposed to a single-bout of nonstop swimming with the addition of 6% body mass until exhaustion. These animals were sacrificed immediately and 24 h after loaded swimming to analyze leukocyte count, MPO content in blood plasma and neutrophils and in muscles, respectively. About 24 h after exercise MPO concentrations in the red portion of quadriceps muscle and in soleus muscle were 4-7-fold higher as compared to the white portion of m. quadriceps. There was an association between the quantity of repetitive bouts of swimming and MPO content in the muscles. The duration of swimming to exhaustion of trained rats was 3.8-fold longer than untrained sedentary control. At rest, plasma MPO concentration was found to be 40% higher in trained rats compared to untrained controls (P < 0.05). Postexercise plasma MPO concentrations were significantly higher both in untrained (+137%; P < 0.05) and trained (+81%; P < 0.05) rats compared to resting values. At rest neutrophil MPO concentration was found to be 33% lower in trained rats compared to untrained controls (P < 0.05). There were no significant differences in muscle MPO concentrations between untrained and trained rats at rest. A single-bout of exercise to exhaustion produced a greater increase in MPO content in untrained compared to trained rats. The data suggest that postexercise neutrophil infiltration is more intensive in red fibers types compared to white fiber types. A smaller neutrophil infiltration in muscles of trained animals after exhaustive exercise suggests a protective effect of previous training to muscle injury.

The electrochemical oxidation of substituted mono-and 3,3′-biindolysines is studied by methods of cyclic voltammetry and electron spin resonance (ESR) combined with in situ electrolysis. In acetonitrile, there occurs easy irreversible electrochemical oxidation and proceed processes of association of generated radical cations via unsubstituted positions of five-membered cycles. Polymeric products of oxidation of 2-arylindolysines, 3-indolysine-2-yl-quinoxalines, and 2,2′-diaryl-3,3′-biindolysines are obtained when cycling potential in the interval −0.3 V → +0.8 V → −1.3 V → −0.3 V (Fc/Fc+). The products deposit on the electrode with the formation of redox-active films that are capable of undergoing reversible oxidation with the formation of stable paramagnetic states registered by the ESR method.

Acyclic and macrocyclic compounds having different numbers of pyrimidine fragments and nitrogen atoms in the polymethylene bridges or in substituents at the pyrimidine rings reacted with 2,3,5,6-tetrachloro-1,4-benzoquinone and 1,4-benzoquinone according to the charge transfer scheme to give products with an ionic structure. The reaction was accompanied by protonation of nitrogen atoms in the polymethylene bridges or in substiuents at the pyrimidine rings and reduction of 2,3,5,6-tetrachloro-1,4-benzoquinone or 1,4-benzoquinone to 2,3,5,6-tetrachlorobenzene-1,4-diol or benzene-1,4-diol, respectively. The isolated products are dielectrics.

The reactions of fullerene C60 with substituted haloketones, including organophosphorus haloketones, in the presence of bases afforded new methanofullerenes containing carbonyl or carbonyl and acetal groups. The structures of the resulting compounds were established by spectroscopic methods. Their electrochemical reduction and oxidation were studied by cyclic voltammetry and ESR spectroscopy. The three-dimensional structures were calculated by the PM3 and DFT/PBE/TZ2P methods.

Routes of white phosphorus activation in the coordination sphere of the nickel complexes with different ligands are shown. The first route is based on the coordination of a P4 molecule with the metal, resulting in the deformation of the P4 tetrahedron without destruction. This case is characteristic of the NiX2L complexes, which are reduced at higher cathodic potentials (|Ered| > 0.9 V) (X = BF4, Br, and Cl; L is bpy in DMF, MeCN, and acetone; 2,9-dimethyl-1,10-phenanthroline (phen) and PPh3 in DMF and acetone). To cleave the P—P bonds in the P4 molecule, this complex should be reduced on the electrode. The second route is the oxidation of white phosphorus in the coordination sphere of the NiII complex. It occurs when the complex has a sufficiently high oxidizing ability and is reduced rather easily (|Ered| < 0.9 V) (X = BF4, L is 1,1,1-tris(diphenylphosphinomethyl)ethane (triphos) in acetone; 1,1′,5,5′-bis[methylenedi(p-phenylene)]di(3,7-diphenyl-1,5-diaza-3,7-diphosphacyclooctane) (n2p2) in DMF; phen and PPh3 in MeCN). The P4 molecule opening is observed to form a new NiI complex containing the (P3) fragment, for example, [(triphos)Ni(P3)Ni(triphos)](BF4)2.

One-electron oxidation of the oximes R2P(=O)C(=NOH)X (X = Cl or Br) generates the nitrile oxides R2P(=O)C+=NO−, which serve as spin traps for unstable carbon-centered radicals.The latter are generated upon addition of PbO2 to a mixture of formohydroximoyl halide with an alcohol or an ether of the general formula R1OCHR2R3 under the action of atomic chlorine (bromine) released during the generation of nitrile oxide. This gives rise to new, more persistent C phosphoryliminoxyls R2P(=O)C(=NO·)C(OR1)R2R3 (R1, R2, R3 = H, Alk). When primary alcohols (R1 = R2 = H) are used, acyl radicals generated at the initial step of the reaction are also trapped by nitrile oxides to give C-acyl-C phosphoryl iminoxyl radicals R2P(O)C(=NO·)C(=O)R3. Hyperfine coupling constants for more than 20 C-phosphoryl-iminoxyls existing in solutions as mixtures of Z- and E-isomers were determined.The effect of the structure of the primary radical (length of the carbon chain, degree of branching, the presence of a ring, and its size) on the radiospectroscopic characteristics of new C-phosphoryliminoxyl radicals was studied.