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In this work, a new application of Cu(II) complex with 3-hydroxy-2-naphtoic acid (Cu-HNA) as a reusable heterogeneous catalyst in the synthesis of tetrahydrobenzo[a]xanthene-11-ones via a one-pot three-component condensation of aryl aldehydes, 2-naphthol, and dimedone in solvent-free condition was reported. At the end of the reaction, with a simple filtration, the catalyst was easily recovered and reused at least five times with no significant loss of its catalytic activity. Appropriate activity and efficient of the catalyst, very good yields, short reaction time, mild and simple work-up, and no use of organic solvents are other benefits of this proposed methodology. [ABSTRACT FROM AUTHOR]

Layered magnesium silicate was modified by water-insoluble chlorin e6 derivatives with two and three ethanolamine fragments on the periphery of the macrocycle by introducing chlorin e6 derivatives into the reaction medium as solutions in hydrochloric acid without the use of organic solvents. The modified layered silicates obtained are characterized by intense fluorescence along with photostability and exhibit photochemical activity in reactions of photosensitized oxidation of model pollutants like xanthene (rhodamine 6G) and azo dyes (methyl orange). [ABSTRACT FROM AUTHOR]

The extraction of trace amounts of U(VI), Th(IV), Am(III), and lanthanides(III) from nitric acid solutions with polyphosphinylbenzenes was studied. The stoichiometry of the extracted complexes was determined, and the influence of the extractant structure, the HNO3 concentration in the aqueous phase, and the nature of organic solvents on the efficiency of metal ions extraction into the organic phase was considered. It was found that compounds with diphenylphosphoryl groups attached directly to the benzene ring in the ortho position in their molecules have the highest extraction ability with respect to actinides and lanthanides. [ABSTRACT FROM AUTHOR]

Isocyanates readily reacts with NaN3 in the presence of ZnCl2 in organic solvents to form the corresponding carbamoyl azides. The formation of carbamoyl azides completed in 5–10 min at room temperature, which prevent the risk of release of hydrogen azide. The obtained carbamoyl azides without isolation can be used for the preparation of 1-substituted tetrazol-5-ones. [ABSTRACT FROM AUTHOR]

Isocyanates readily reacts with NaN3 in the presence of ZnCl2 in organic solvents to form the corresponding carbamoyl azides. The formation of carbamoyl azides completed in 5–10 min at room temperature, which prevent the risk of release of hydrogen azide. The obtained carbamoyl azides without isolation can be used for the preparation of 1-substituted tetrazol-5-ones. [ABSTRACT FROM AUTHOR]

The kinetics of the metal exchange reactions of cadmium(II) 5,15-dinitro-2,3,7,8,12,13,17,18-octaethylporphyrinate with copper(II) and zinc(II) chlorides in DMF and DMSO were investigated by the spectrophotometric method. The kinetic parameters of the metal exchange reaction were determined. A possible stoichiometric reaction mechanism was proposed. The effect of the solvent and solvate salt nature on the rate of the metal exchange reaction was revealed. [ABSTRACT FROM AUTHOR]

The reactions of 1-germatranol hydrate with malonic, succinic, maleic, cork, sebacic acids, and bistrimethylsilyl ester of succinic acid, and also of bis(germatran-1-yl)oxane with succinic acid in acetonitrile, water, methanol, and dimethylsulfoxide were studied. In organic solvents, mono- and dicarboxyl-substituted 1-germatranols are formed, which, like 1-germatranol, are reversibly hydrolyzed with water in an acidic medium. Removing water from reaction mixtures due to evaporation and a topochemical reaction increases the yield of esterified 1-germatranol. [ABSTRACT FROM AUTHOR]

Extraction of rare earths(III) from hydrochloric acid solutions with mixtures of new tridentate carbamoylmethylphosphine oxides Ph2P(O)CH2CON(R)CH2CH2P(O)Ph2 (R = Me, Bu, Oct) and 4-benzoyl-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one in organic solvents has been studied. The observed strong synergistic effect has been attributed to the formation of hydrophobic mixed-ligand rare earth complexes in the organic phase. Stoichiometry of the extractable complexes has been determined, and extraction constants have been calculated. The effect of organic solvent and composition of the aqueous phase on the extraction efficiency has been analyzed. [ABSTRACT FROM AUTHOR]

Exploration (factor, cluster, and decision tree), regression (multiple linear regression), and neural network (regression, classification) models of clustering, approximation and prediction of the stability constants of cation complexes with ionophore antibiotics (nonactin, monactin, dinactin, trinactin, ennatin B, monensin A, and valinomycin) according to the properties of organic solvents (methanol, ethanol, acetonitrile, and nitrobenzene) and cations (Li+, Na+, K+, Rb+, Cs+, Tl+, Ag+, NH4+, Mg2+, Ca2+, Sr2+, Ba2+, and Mn2+) have been developed. It has been shown that neural network performance is better than that of multiple linear regression (the correlation coefficient on the training sample 0.756 compared to 0.697). The neural network classifier and the classification tree has confirmed the clustering of stability of ionophore–cation complexes carried out by the exploratory k-means method by 97.2%. The prognostic capabilities of the constructed multilayer perceptron have been demonstrated. [ABSTRACT FROM AUTHOR]

The reaction of sulfoxides with peroxy acids in various organic media was studied. The reaction mechanism involves the rapid formation of a sulfoxide-–peroxy acid intermediate which decomposes in the second stage to form carboxylic acid and the corresponding sulfone. The second stage is the rate-limiting step. The reaction medium significantly affects the rate of oxidation. The calculated activation parameters of the oxidation process indicate a compensation effect in the investigated reaction. Correlations between the main physicochemical parameters of solvents and the effective rate constants (k) of dimethyl sulfoxide oxidation with peroxy acids were found. Depending on the reaction conditions, the main factors affecting the k values are specific and nonspecific solvation of the reactants and structural factors. [ABSTRACT FROM AUTHOR]

Extraction of rare-earth elements(III) ions from chloride solutions with mixtures of 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone and phosphoryl-containing podands in organic solvents has been studied. The observed significant synergistic effect is associated with the formation of hydrophobic mixed-ligand complexes of rare-earth elements(III). The stoichiometry of the extracted complexes has been determined, and the extraction constants have been calculated. The influence of the phosphoryl-containing podand structure, the organic solvent nature, and the aqueous phase composition on the efficiency of the extraction of rare-earth element(III) ions into the organic phase has been considered. [ABSTRACT FROM AUTHOR]

The association of N-[3-(dimethylamino)propyl](meth)acrylamides in tetrachloromethane, tetrahydrofuran, and N, N-dimethylformamide has been studied by means of IR spectroscopy and quantum-chemical simulation at the B3LYP/6-31+G(d,p)/PCM level. The effect of the hydrogen bonding capacity of the solvent on the degree of participation of N-[3-(dimethylamino)propyl](meth)acrylamides in hydrogen bonding with the formation of the amide-solvent type self-associates and heteroassociates has been elucidated. [ABSTRACT FROM AUTHOR]

Models of multiple linear regression and multilayer artificial neural network have been developed for modeling and predicting the stability constants of sodium and potassium coronates basing on the properties of aqueous-organic solvents (water-methanol, water-propan-2-ol, water-acetonitrile, and water-acetone). The values of the coronates stability constants in water-ethanol solvents have been predicted, and the predictions of the models of multiple linear regression and an artificial neural network models have been compared. The contributions of electrostatic, cohesive, and electron-donating interactions to the increase in the stability of the coronates have been quantitatively assessed basing on the models of multiple linear regression and the principle of free energies linearity. Neural network models based on unsupervised (multilayer perceptrons) and supervised (Kohonen networks) learning algorithms have been developed to classify the stability of sodium and potassium coronates. The neural network classifiers have fully confirmed the classification of the coronated stability via the k-means exploration method. [ABSTRACT FROM AUTHOR]

Four complexes [Ni(DMA)2(H2O)4]Cl2·2H2O, [Ni(DMF)2(H2O)4]Cl2·2H2O, and [Ni(DMA)6][NiCl4], [Ni(DMF)2(H2O)2Cl2] were isolated from ternary water-organic saline systems containing nickel chloride and N, N-dimethylacetamide-water and N, N-dimethylformamide-water binary solvents. The obtained complexes were studied by X-ray structural analysis. The formation of hydrogen bonds between water molecules of the nickel ion solvate sphere, chloride ions, and non-coordinated water molecules located in the cavity of the crystal structure was detected. [ABSTRACT FROM AUTHOR]

4,5-bis[(4-phenoxy)phenoxy]phthalonitrile was obtained by the reaction of 4,5-dichlorophthalonitrile with 4-phenoxyphenol. On its basis 2,3,9,10,16,17,23,24-octakis-[(4-phenoxy)phenoxy]phthalocyanine and its single- and double-decked complexes with erbium were synthesized. Spectral-luminescent properties of resulting phthalocyanines were studied. The tendency of phthalocyanines to association in dichloromethane depends on the structure of their molecules. [ABSTRACT FROM AUTHOR]

The possibility of using spectrophotometric method for the evaluation of ozone solubility in highly concentrated solutions by measuring absorption in the Chappuis band directly in the liquid phase has been demonstrated. The solubilities of ozone in various organic solvents have been determined, and its limiting solubility has been calculated. The molar absorption coefficient in the long-wavelength band of ozone has been found to depend on the solvent nature. [ABSTRACT FROM AUTHOR]

The metal-exchange reaction between Cd(II) octa-(4-bromophenyl)porphyrinate and cobalt chloride in DMF and DMSO was studied by UV-Vis spectroscopy. The kinetic parameters of the metal-exchange reaction were calculated. A possible mechanism of the reaction was established. An effect of the nature of the solvent and metal salt on the reaction rate was revealed. Comparative analysis of the apparent rate constants of the metal exchange reaction between CoCl2 and Cd(II) octa-(4-bromophenyl)porphyrinates and Cd(II) octa-(4-bromophenyl)tetraazaporphyrinate in DMF and DMSO was performed. [ABSTRACT FROM AUTHOR]

О′,О′-Diethyl-[2-(3,4-dicyanophenoxy)phenyl]phosphonate has been synthesized for the first time and introduced in template condensation on lithium and zinc cations to prepare a series of new neutral and acidic phthalocyanines containing four fragments of 2-oxyphenylphosphonic acid. A scheme of modification of the peripheral substituents at the phosphoryl group was developed allowing a targeted synthesis of phthalocyanine ligands and complexes soluble in organic solvents or aqueous media. [ABSTRACT FROM AUTHOR]

On the way to solving the problem of developing an ecofriendly technology for preparing hydrophobic protective coatings to replace the existing technology involving casting from polymer solutions in toxic organic solvents, amphiphilic organosilicon oligomers, promising emulsifiers for preparing aqueous emulsions of organosilicon polymers, were synthesized. The synthesized oligomers were used to obtain stable aqueous emulsions of a film-forming silicone block copolymer. The resulting emulsions can be used to form hydrophobic protective coatings on the surface of construction materials. It was shown that the contact angle of wetting depends on the specific features of the preparation of the emulsion and reaches a maximum of 134°. [ABSTRACT FROM AUTHOR]

New metal-containing polymers, poly(salicylidene azomethines) containing metal atoms (Co, Ni, Cu) in the backbone, were synthesized from aromatic carbazolediamine derivatives. It was found that the polymers with a decyl substituent in the carbazole fragment are soluble in organic solvents (chloroform, methanol, DMSO, DMF) and exhibit film-forming and semiconductor properties. IR and NMR spectroscopy was used to show that the semiconductor properties of the new polymers are associated with the presence in the polymer backbone of transannular polyconjugation zones formed by intramolecular donor-acceptor interactions of the metal and nitrogen valence shells. [ABSTRACT FROM AUTHOR]

Predictive correlation-regression and neural network models for description of the properties of aqueous-organic solvents on the strength of acetic and benzoic acids have been developed. Significant descriptors affecting the dissociation equilibrium of the acids have been found. The features of the solvation (reflected in the electrostatic, cohesion, and electron accepting interactions) on the acids strength have been disclosed. Prediction of the dissociation constants of acetic and benzoic acids has been successfully performed using a three-layer perceptron. Prospects of the neural network modeling for prediction of organic acids strength in aqueous-organic media have been demonstrated. A neural network classifier of acetic and benzoic acids strength based on the aqueous-alcoholic solvents descriptors has been developed and trained. [ABSTRACT FROM AUTHOR]

Decisive rule for classification and prediction of benzoic acid strength from dielectric constant and Kamlet-Taft parameter of the mixed solvents (water-methanol, water-ethanol, and water-2-propanol) has been elaborated basing on the results of multivariate exploratory analysis. The rule has been verified using the independent experimental data on dissociation constant of benzoic acid in water-dioxane and water-dimethylsulfoxide mixtures. Two-parameter linear regression model of the Gibbs energy of benzoic acid dissociation as a function of the properties of aqueous-alcoholic solvents has been built, and the contributions of dielectric and cohesion medium properties to the decrease in the acid strength have been shown. [ABSTRACT FROM AUTHOR]

Phthalocyanines containing gallic acid moieties were synthesized and investigated by the method of electron absorption spectroscopy. It was shown that in organic solvents the prepared phthalocyanines exist predominantly in associated form. [ABSTRACT FROM AUTHOR]

In this article, the first use of silicotungstic acid (HSiWO) as a catalyst for the synthesis of octahydroxanthene-1,8-diones by the reaction of 5,5-dimethylcyclohexane-1,3-dione (dimedone) with various aldehydes under thermal solvent-free conditions is described. The obtained results showed that the catalyst has a high catalytic activity, and the desired products were obtained in high yields. Moreover, the catalyst was found to be reusable, and a considerable catalytic activity still could be achieved after the fifth run. Easy work-up and avoidance of using harmful organic solvents are the other advantages of this simple procedure. [ABSTRACT FROM AUTHOR]

Choline tetrachloroferrate with a magnetic response property is applied in multicomponent one-pot synthesis of 2-amino-4 H-chromenes as effective catalyst. The catalyst is characterized by the UV-Vis and Raman spectroscopies and by the electrospray ionization mass spectrometry. [ABSTRACT FROM AUTHOR]

Solubility of salts in the systems MCl-HO-Solv (M = Co, Ni) and CoBr-HO-Solv (Solv = dimethyl sulfoxide, dimethyl formamide, and dimethyl acetamide) at 25°C was measured experimentally. Dominating species of cobalt and nickel halides existing in various concentration regions were identified by analysis of electron absorption spectra. It was shown that the major factor defining solubility is the interaction of halocomplexes of metal ions with solvent molecules. [ABSTRACT FROM AUTHOR]

Solubility at 25°C has been determined in the MSO-HO-Solv systems (M = Co, Cu, or Cd; Solv = dimethyl sulfoxide, dimethyl formamide, dimethyl acetamide, tetrahydrofuran, or dioxane) via the isothermal saturation method. Analysis of the solubility as function of the permittivity and donor power of solvents along with the information on the cations radius leads to the conclusion that ion-ion association dominates over solvation interactions in the studied systems. [ABSTRACT FROM AUTHOR]

The interaction of a series of acrylic and cinnamic acid amides with bis(pentafluorophenyl)-phosphinic acid proceeds vigorously at room temperature without any catalyst in the presence of the organic solvents providing for a high fraction of the >P-OH tautomer of the phosphinic acid. The reactions have afforded (2-carbamoylethyl)bis(pentafluorophenyl)phosphine oxides in a high yield. [ABSTRACT FROM AUTHOR]

The metal-exchange reaction between Cd(II) octa(4-bromophenyl)tetraazaporphyrinate and cobalt chloride in dimethylformamide and dimethyl sulfoxide was studied by spectrophotometry. Kinetic parameters of the metal-exchange reaction were determined. A possible stoichiometric mechanism of the reaction was proposed. Cobalt(III) octa(4-bromophenyl)tetraazaporphyrinate was synthesized and characterized. [ABSTRACT FROM AUTHOR]

Oxidation of ferrocenylboric acid with hydrogen peroxide in organic solvents and in aqueous solutions in the presence and in the absence of acids and bases has been investigated by electron absorption spectroscopy. Kinetics of FcB(OH) oxidation in neutral, acidic, and basic media has been studied; possible mechanisms of the reactions accounting for the substituent acting as the Lewis-type acidic center have been suggested. [ABSTRACT FROM AUTHOR]

The organic bismuth compounds PhBi(OCCH=CHCH) and PhBi(OCEt) decompose under scattered light in the presence of spin traps (2-methyl-2-nitrosopropane and C-phenyl- N- tert-butylnitrone) in organic solvents (acetonitrile, benzene, toluene) to form adducts of phenyl radicals with the traps. [ABSTRACT FROM AUTHOR]

Enthalpies of dissolution at infinite dilution (298.15 K) of aniline, N-methylaniline, and N,N-dimethylaniline in a series of proton-acceptor solvents of different classes of compounds have been measured. The solvation enthalpies have been determined, and its relationship with the anilines structure has been analyzed. Enthalpy of hydrogen bonding in the complexes of aniline (1: 2) and N-methylaniline (1: 1) with the solvents has been calculated. In the case of aniline complexes, negative cooperativity of hydrogen bonding has been revealed, the effect enhancing with increasing the solvent proton-acceptor ability. [ABSTRACT FROM AUTHOR]

Specific features of formyl- and acetylferrocene oxidation with peroxides ROOR (R = H, tert-CH) in different solvents are studied. It is shown that despite of the presence in complexes of strong electronacceptor substituents they can be oxidized with hydrogen peroxide in the absence of strong Brønsted acids. Dilution of water with organic solvent leads to deceleration and complete standstill of the reaction. In the absence of acids the second order of the process with respect to peroxide and first one with respect to the metal complex was evaluated. In the presence of perchloric or trifluoroacetic acid the order with respect to peroxide decreases to the first one. The dependence of the reaction rate on the concentration of acid has an extremum point. The activity of other peroxides in the reaction with the above-mentioned compounds is significantly lower than the activity of hydrogen peroxide. Probable alternative mechanisms of oxidation of the abovementioned ferrocenes with hydrogen peroxide in the presence and in the absence of acids differing in the way of coordination of reagents with one another and considering direct participation of substituent in the oxidation is suggested. [ABSTRACT FROM AUTHOR]

The stability constant (log K) and the thermodynamic parameters (free energies, enthalpies, and entropies) of the complexation of Co cation with 15-crown-5 (15C5) in acetonitrile-methanol (AN/MeOH), acetonitrile-nitrobenzene (AN/NB), acetonitrile-dichloromethane (AN/DCM) and acetonitrile-1,2-dichloroethane (AN/DCE) binary solvent solutions were calculated from the experimental conductance data at different temperatures. The complexation behavior of the crown ether used in these media was discussed in view of the estimated parameters. In all solvent systems, 15-crown-5 formed a 1: 1 complex with Co cation. The stability order of (Co-15C5) complex in the binary mixed solvents at 25°C was found to be: AN/NB > AN/DCM ≈ AN/DCE > AN/MeOH. In most cases, a non-linear relationship was observed for changes of log K of (Co-15C5) complex versus the composition of the binary mixed solvent systems. The experimental results show that the standard thermodynamic parameters of the complexation process change with the nature and composition of the binary solvent solutions. [ABSTRACT FROM AUTHOR]

Reaction of epoxidation of α-pinene and Δ-carene with peroxydecanoic acid in various organic solvents was studied. Effective activation energies of oxidation of α-pinene and Δ-carene with peroxydecanoic acid in various media are evaluated. It is shown that reaction medium significantly affects the rate of the process. Correlation dependences connecting the rate of epoxidation with main parameters of solvents are found. [ABSTRACT FROM AUTHOR]

Kinetic relationships of oxidation of 1,1′-diethylferrocene and decamethylferrocene with peroxides ROOR (R = H, t-CH) in organic solvents were studied and the composition of oxidation products was established. It is shown that reactivity of (CHCH)Fe is significantly lower than that of Cp*Fe [Cp* = η-C(CH)] which is seen from the ability of the first metal complex to undergo oxidation with a notable rate only in the presence of Brønsted acids, whereas the second substance is oxidized both in the presence and in the absence of these acids. Two possible mechanisms of oxidation of metal complexes in the presence of strong acids are discussed. One of them is based on the ability of ferrocene to fast and equilibrium protonation with the formation of CpFe-H structure. Another one considers the ability of metal complexes to coordinate peroxides with the formation of weakly bound charge transfer complexes of the composition CpFe·ROOR. The possibility of their formation is confirmed by the oxidation of CpFe with hydroperoxides in the absence of acids. [ABSTRACT FROM AUTHOR]

The reaction of ferrocenylacetic acid and its methyl ester with peroxides ROOR (R = H, t-Bu) in organic solvents was studied. It is shown that direct involvement of the substituent in this process leads to abnormally high reactivity of the acid toward HO and t-BuOOH as compared with both the ester and ferrocene in a model system of CpFe + PhCOOH. An unusual shift of the absorption maximum of the ferrocenyl cation formed in the reaction course to longer wavelengths reaching up to several tens of nanometers was discovered. [ABSTRACT FROM AUTHOR]

We have studied the autoxidation of ferrocenecarboxylic acid and its methyl ester in organic solvents in the presence of perchloric and trifluoroacetic acids. Based on the results of kinetic studies and data on the composition of the reaction products, we suggested the possible reaction mechanisms, including those of molecular and radical-chain macrostages of the process. The features of the solvent influence on the rate of oxidation of metallocomplexes and the reasons for its extreme dependence with increasing concentration of perchloric acid are discussed. [ABSTRACT FROM AUTHOR]

(1,2,3,7,9-pentamethyldipyrrolylmethen-8-yl)(1,2,3,7,8-pentamethyldipyrrolylmethen-9-yl)-methane and bis(1,2,3,7,9-pentamethyldipyrrolylmethen-8-yl)trifluoromethylmethane hydrobromides were synthesized and characterized spectrally (1H NMR, IR, electron absorption spectra). A comparative study was performed of the effect of the bonding site (α- or β-position of the dipyrrolylmethene) with the methane structural fragment connecting two dipyrrolylmethene chromophores, and trifluoromethyl group on the spectral properties of the molecules of compounds dissolved in organic solvents of different nature and their resistance to thermal oxidative degradation. [ABSTRACT FROM AUTHOR]

In the study of the solution-solid phase equilibrium in CuX-S-HO system (X = Cl, Br, S = dimethyl sulfoxide, N, N-dimethylformamide, tetrahydrofuran, 1,4-dioxane) at 25°C we established the effect of the solvent properties and the type of the halide ligand (dielectric premeability, donor number, hydrophobicity) on the solubility of the solid phase in binary and ternary systems, the length of the fields of crystallization of the compounds and the structure of the water-organic solvates. [ABSTRACT FROM AUTHOR]

Luminescence and chemical acceptors methods were used to study the photosensitized formation of singlet molecular oxygen (O, Δ) by monomer and aggregated forms of copper tetra-4-(morpholine-4-yl)-tetra-5-(2-naphthoxy)phthalocyanine in benzene, benzene- d, acetone, DMF, and pyridine. The values of O quantum yield were determined. The effectiveness of the O photoproduction was shown to be reduced due mainly to the aggregation of the copper phthalocyanine molecules. [ABSTRACT FROM AUTHOR]

The present state and prospective directions of wood thermochemical liquefaction are considered and summarized, including hydrothermal liquefaction, liquefaction in organic solvents, and major methods of pyrolysis. The most promising techniques among them are liquefaction in formic acid and phenols and fast pyrolysis methods. [ABSTRACT FROM AUTHOR]

A 1:1 reaction of [HO(CH)]P with 4-hydroxy-3-methoxy-cinnamaldehyde (coniferaldehyde) or 3,5-dimethoxy-4-hydroxycinnamaldehyde (sinapaldehyde) in acetone at room temperature affords phosphonium zwitterions of the type RPCH(4-O-Ar)CHCHO; other phosphines [R = Et, n-Bu, (CH)CN, and p-Tol] do not react under the same conditions. In alcohols R'OH(D) [R' = CD, Et, (CD)CD, s-Bu, HOCHCH], the above phosphines (except the cyano-derivative) and those where R = i-Pr, Cy, MePh, MePh do react within an equilibrium established between the reactants and the zwitterion-hemiacetal products RPCH(4-O-Ar)CHCH(OH)(OR′) that are formed as a mixture of two diastereomers. The nature of the phosphine and the alcohol affects the equilibrium and the diastereomeric ratio. [ABSTRACT FROM AUTHOR]

The photogeneration of the singlet molecular oxygen (O) by copper tetra(4- tert-butyl) phthalocyanine in organic solvents of different nature was substantiated. The apparent quantum yields of Oin benzene and pyridine were determined. The data obtained indicate an influence of the coordinating properties of the solvent on the Oyield. However, this factor is not 'critical' as in the case of photogeneration of Oby copper tetra(5- tert-butylpyrazino)porphyrazine. [ABSTRACT FROM AUTHOR]

Copolymerization of 1-vinyl-1,2,4-triazole with crotonic aldehyde under the conditions of free-radical initiation has been studied. 1-Vinyl-1,2,4-triazole was found to be more reactive than crotonic aldehyde. The composition and structure of copolymers were determined by the elemental analysis, IR and quantitative C NMR spectroscopy. New polyfunctional water-soluble copolymers possessing thermostability up to 300°C were obtained. [ABSTRACT FROM AUTHOR]

Investigation of extraction of fullerene mixture from the fullerene soot obtained by plasma erosion of graphite rod in helium atmosphere with different solvents such as α-chloronaphthalene, o-dichlorobenzene, o-xylene, toluene, benzene, carbon tetrachloride, and n-hexane at 25°C was carried out. Completeness and effectiveness of extraction as well as relative content of light (C, C) and heavy (C, C, C) fullerenes in the extract were evaluated. [ABSTRACT FROM AUTHOR]

1,3,5-Tris[bis(η-cyclopentadienyl)chlorovanadium]melamin is prepared in high yield by the reaction of N,N′-bis(trimethylsilyl)dicyandiamide with bis(η-cyclopentadienylvanadium) dichloride in tetrahydrofuran. As side products, trimethylchlorosilane and cyclopentadiene formed. Reaction of N,N′-bis(trimethylsilyl) dicyandiamide with benzoyl chloride results in the formation of tris(benzoyl)melamin. [ABSTRACT FROM AUTHOR]

The properties of the heterophase system perfluorodecalin-acetonitrile differ significantly from those of other combinations of the organic solvents limitedly soluble in each other. While for the most of such combinations the distribution coefficients ( K) of homologues increase in going from the simplest to next members of the series, in the case of perfluorodecalin-acetonitrile they remain almost constant. This provides a possibility to use the values of K directly for the group identification of analytes, and first of all allows distinguishing isomeric alkenes and cycloalkanes, as well as the isomers of the hydrocarbons with greater formal unsaturation. [ABSTRACT FROM AUTHOR]

By comparison of reactivity of the ferrocene derivatives differing in the nature of the substituents the conditions were revealed of their participation as Brønstedt and Lewis acidic centers in the process of the metallocomplex molecular oxidation with oxygen in terms of manifestations of the effects of rapproachment and orientation. From this standpoint were analyzed the experimental data obtained in the oxidation of methyl ferrocenylacetate. A probable mechanism of the process is proposed that includes the molecular and radicalchain macro steps. [ABSTRACT FROM AUTHOR]

Transport properties of several aromatic polyamides among which there exist fairly subtle structural differences were examined in perva-poration of water-isopropanol solutions. The dependences of the flux density on the membrane area and the oscillatory kinetics of permeability were established, and an unstable steady state arising via predominant permeation of an organic solvent through a highly hydrophilic polymeric membrane was revealed. Conductometric examination of the swelling kinetics showed that chitosan swelling in water gives rise to instabilities in the form of macrofluctuations of local sorbate concentration distribution in the polymer. The wavelet analysis of the time series of the stochastic oscillations was carried out. [ABSTRACT FROM AUTHOR]