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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]

Features of the oxidation of hydroxymethylferrocene with molecular oxygen in organic solvent in the presence of weak and strong Broensted acids were studied. The resulting data were compared with published data on ferrocene and hydroxyferrocene oxidation, which made it possible to assess the trend in the oxidation mechanism in going from ferrocene π complexes to their hydroxyferrocene and hydroxymethylferrocene analogs. A conclusion was drawn that each of the ferrocenes reacts with oxygen in quite a specific way. [ABSTRACT FROM AUTHOR]

The distribution ratios of novocaine and p-aminobenzoic acid between water and 12 organic solvents were correlated with linear multiparameter equations. [ABSTRACT FROM AUTHOR]

The influence of physicochemical properties of solvents on the solubility of radon in them can be described by multiparameter linear equations taking into account various solvent characteristics; the decisive (and negative) effect on the radon solubility is exerted by the cohesion energy density and polarity of the solvent. This approach is efficient for summarizing data on the distribution ratios of radon between organic and aqueous phases. [ABSTRACT FROM AUTHOR]

The kinetics of the reaction of O,O-diphenyl phosphorohydrazidothioate with phenyl isothiocyanate at 25°C in benzene in the presence of organic bases is studied. The dependences of the catalytic activity on the nature and structure of organic bases and on various parameters characterizing their basicity are analyzed. The catalytic activity exhibited in the formation of phosphorus-containing thiosemicarbazides by donor solvents added to benzene correlates well with both spectroscopic and thermodynamic parameters of basicity: Taft (p K HB), Koppel-Palm ( B), and Gutmann ( DN) parameters. A common mechanism of the base catalysis of the thiosemicarbazide formation by organic bases of different classes is suggested and discussed. [ABSTRACT FROM AUTHOR]

Solvation and complexation of Cu(II), Ni(II), and Co(II) with adipic acid dihydrazide (L) in aqueous and aqueous-ethanol solutions (ethanol mole fraction 0.07–0.68) were studied by spectrophotometry. The formation constants of the species M(LH)3+, ML2+, M2L4+ (μ = Cu2+, Ni2+, Co2+), and also M2L and ML (μ = Cu2+, Ni2+) were determined. With Cu(II), the complexes Cu(LH), CuL(LH)3+, and Cu2L(LH)5+ were also detected and characterized. Evidence is given for the hydrazide coordination mode: tridentate in ML2+, bidentate in M(LH)3+ and ML, and tetradentate in M2L4+ and M2L. The ligand exchange reactions involving CuL2+, Cu(LH)3+, Cu(LH), CuL(LH)3+, CuL, and Cu2L(LH)5+ in aqueous solutions of Cu(II) were revealed and kinetically characterized by nuclear magnetic relaxation. The heretofore unknown rate constants of formation of these complexes were calculated from the thermodynamic and kinetic parameters. Factors controlling the rate constants of the complex formation and chemical exchange are discussed. [ABSTRACT FROM AUTHOR]

A comparative study is made of the solvent effect on the kinetics of arylsulfonation of benzhydrazide with 3-nitrobenzenesulfonyl chloride in aqueous-organic solutions (water-2-propanol, water-dioxane, water-tetrahydrofuran, and water-acetonitrile) at 298 K. The arylsulfonation product can be obtained in nearly theoretical yield at the initial reactant concentrations of 0.1 M in the water-dioxane, water-MeCN, and water-THF mixtures containing above 30 wt % water. [ABSTRACT FROM AUTHOR]

The enthalpies of solution of formamides, acetamides, and propionamides with various extents of N-substitution in aqueous solutions of propylene glycol and 1,2-butanediol (concentration ≤4 mol kg-1) at 298.15 K were measured. The enthalpies of transfer of the amides from water to mixed aqueous-organic solvents were determined and discussed in combination with data on the enthalpies of transfer of amides from water to aqueous ethylene glycol solutions. The enthalpy coefficients of pair interactions of amides with 1,2-diols in water were calculated and used for evaluating the group components on the basis of the principle of group additivity of contributions. As the hydrophobic properties of polyfunctional nonelectrolytes are enhanced, the coefficients increase, which is due to the growth of the hydrophobic component of the interaction. [ABSTRACT FROM AUTHOR]

The effect of dielectric and chemical (donor-acceptor interactions, cohesion energy density) properties of aqueous-organic solvents (water-methanol, water-2-propanol, water-acetonitrile, water-acetone, water-dioxane) on the thermodynamic functions of complexation of sodium and potassium cations with 18-crown-6 ether at 298 K was subjected to overall correlation analysis. [ABSTRACT FROM AUTHOR]

The results of the calorimetric studies of the enthalpies of mixing of some ionic liquids, 1-butyl-3-methylimidazolium chloride and acetate, with water, pentanol, dimethyl sulfoxide and dimethylformamide are presented. Protic solvents interact with the ionic liquid anion, wheras aprotic, with the cation. The mixing enthalpy depends on the dissociation degree of the ionic liquid. [ABSTRACT FROM AUTHOR]

Data on the solubility of 4,4′-isopropylidenediphenol in organic solvents can be quantitatively correlated with a linear three-parameter equation. The parameters exerting a decisive effect on the solubility are the polarity and basicity of solvents, favoring formation of intermolecular hydrogen bonds. At the same time, an increase in the cohesion energy of the medium decreases the solubility of the title compound. [ABSTRACT FROM AUTHOR]