E. A. Miroshnichenko

Thermochemistry of alkyl derivatives of urea

A thermodynamic study was carried out on urea and 12 of its alkyl derivatives by the methods of combustion calorimetry, vapor formation, and differential scanning calorimetry. The numerical data obtained permitted determination of the enthalpy of formation of the above substances under standard conditions and in the gas phase. An additive scheme was proposed for calculating the thermodynamic properties of alkyl substituted urea.

Heats of combustion of nitromethane and dinitromethane; enthalpies of formation of nitromethyl radicals and energies of dissociation of bonds in nitro derivatives of methane

1. The heats of combustion of nitromethane and dinitromethane, 168.0±0.3 and 137.3±0.2 kcal /mole, respectively, were measured. 2. The energies (kcal/mole) of dissociation of the C-N bond in nitro derivatives of methane were estimated on the basis of the available data: 60.3 in nitromethane, 53.8 in dinitromethane, 45.7 in trinitromethane, and 39.3 in tetranitromethane. 3. The energies (kcal/mole) of formation of nitromethyl radicals\([^ \cdot CH_2 NO_2 31.6;^ \cdot CH(NO_2 )_2 37.5;\) and\(^ \cdot C(NO_2 )_3 49.8]\) were estimated, and lead to energies of dissociation of the C-H bond in nitro derivatives of methane ∼103 kcal/mole.

Thermochemistry of glyceryl trinitrate

Conclusions1.Thermochemical investigations of glyceryl trinitrate were carried out to obtain the enthalpy of formation in the standard state, the enthalpy of vaporization, and the enthalpy of formation in the gas phase.2.The thermodynamic parameters of the intermolecular interactions in liquid glyceryl trinitrate and in solution were evaluated on the basis of solvation effects in nitromethane.

Energy characteristics of nitrooxazolidines and their radicals

The standard molar enthalpies of combustion for three methyl and dimethyl nitrooxazolidine derivatives in the liquid and crystalline states were determined using a high-precision static bomb combustion calorimeter. The resulting values were used to derive the standard molar enthalpies of formation of the azidomethyl-N-nitrooxazolidines. The standard molar enthalpies of vaporization for these compounds were measured using a Calvet microcalorimeter. The enthalpies of formation of some nitrooxazolidine-derived radicals and biradicals were calculated.

Thermochemical investigation of trioxaazaboratricycloalkanes

ConclusionsA thermochemical study has been made of trioxaazaboratricycloalkanes by means of combustion and vaporization calorimetry. From the numerical values obtained, the enthalpies of formation of these compounds in the standard state and in the gas phase were established; also, the strength of the boron-nitrogen bond was estimated as ∼57 kJ/mole.

Intermolecular interaction in polyconjugated systems

1. The thermochemical characteristics of a number of low-molecular and polymer compounds with a system of conjugation were investigated. 2. The energies of stabilization of the systems studied were found, and it was proposed that they are due chiefly to intermolecular interaction.

The energy of the N→O bond in 3-nitroisoxazoline N-oxide

The enthalpy of combustion of 3-nitroisoxazoline has been determined as ΔHc298.15=−414±0.3 kcal/mole and that of 3-nitroisoxazoline N-oxide as ΔHc298.15=−406.6±0.5 kcal/mole. From the values for the heats of combustion and evaporation, the standard enthalpies of formation have been calculated and the energy of the N→O bond has been evaluated at 64±3 kcal/mole.

Determination of the enthalpy of the 1,3-dipolar cycloaddition reaction of nitrone ethers

The enthalpy of the 1, 3-dipolar cycloaddition of 2-nitroisoxazoline N-oxide to ethylene has been determined.

Thermochemical investigations of copolymers and block copolymers containing polyvinylene blocks in their structure

1. A thermochemical method was used to analyze the composition and structure of copolymers and block copolymers containing polyvinylene blocks in a macrochain. 2. In the copolymerization of phenylacetylene with maleic anhydride, products with a structure containing blocks of conjugation are formed. 3. The values of the molecular weights of the block copolymers of polyphenylacetylenes with maleic anhydride and furmarodinitrile were estimated on the basis of a determination of the heats of combustion.