L. T. Eremenko

Standard enthalpies of formation of certain nitro compounds

Summary1.A thermochemical study has been made of 22 nitro and fluoronitro-containing organic compounds. Their standard enthalpies of combustion and formation have been determined.2.The contribution of certain groups and interactions to the value of ΔHf° of the nitro compounds in the condensed state have been calculated.3.Feasibility has been demonstrated for the calculation of standard enthalpies of formation of nitro and fluoronitro-containing substances by the group contribution method.

Preparation and properties of N-fluoro- and N-nitrobis(2,2,2-trinitroethyl)ureas

Fluorination and nitration of bis(2,2,2-trinitroethyl)urea has given the novel N-fluoro-bis(2,2,2-trinitroethyl)urea and N-nitro-bis(2,2,2-trinitroethyl)urea. The thermal decomposition rates and parameters for bis(2,2,2-trinitroethyl)urea and its derivatives have been found, and the standard enthalpies of combustion, and the standard enthalpies of formation of these compounds calculated therefrom, have been determined.

Nitration equilibrium in the glycerol-aqueous-nitric-acid system 3. PMR parameters, conformational structure, and main properties of glycerol and its nitrates

Studies of PMR spectra at a frequency of 294 MHz for glycerol, and its mono-, di-, and trinitrates have been carried out in aqueous solutions of nitric and sulfuric acids and in deuteroacetonitrile. The conformational composition weakly depends on the medium, temperature, and the number of nitrate groups in the molecule. Conformers with CH2 and OH (or ONO2) located in a trans position have a certain preference. The basicity parameters pKBH+ and Φe and semiprotonation points of glycerol (separately for primary and secondary hydroxyl) and glycerol dinitrates have been determined. In these properties glycerol and its dinitrates are similar to monatomic alcohols. Acidity functions of solutions of sulfuric and nitric acids were calculated using glycerol and glycerol dinitrates as indicators. Unlike Hammett bases, alcohols in H2O-H2SO4 and H2O-HNO3 systems of identical molar composition are protonated practically identically.

Study of nitration equilibrium in the glycerin-aqueous nitric acid system. 1. Dependence of the equilibrium constants of nitration reactions on the temperature, acidity of the medium, and structure of the nitrated compound

The equilibrium constants of seven sequential-parallel reactions of conversion of glycerin into glycerin trinitrate in aqueous HNO3 were measured. The effect of the acidity of the medium on the equilibrium nitration constants is correlated with processes of protonation of glycerin and its nitrates. The equilibrium nitration constants are higher for primary hydroxides than for secondary hydroxides, and they decrease in both series in going from glycerin to its dinitrates.

Synthesis and reactions of 2-nitro-1-propen-3-ol

Conclusions1.The reaction of the sodium salt of 2-nitro-1,3-propanediol with an aqueous nitric acid solution gave 2-nitro-1-propen-3-ol. Chlorination and bromination of this compound gave 2,3-dichloro- and 2,3-dibromo-2-nitropropanols.2.The addition of trinitromethane and fluorodinitromethane to 2-nitro-1-propen-3-ol gave 1,1,1,3,5,5,5-heptanitro- and 1,5-difluoro-1,1,3,5,5-pentanitropentanes.

Kinetics of the thermal decomposition of N,N-(dinitro)alkylamines

Conclusions1.The thermal decomposition of N,N-dinitroamines is homogeneous and unimolecular in the gas phase. The limiting step of the process is the rupture of the N-NO2 bond.2.The activation parameters of the process imply that the dinitroamine group is more reactive than the mononitroamine group in thermal decomposition. The energy of dissociation of the N-NO2 bond in dinitroamines is ∼42 kJ/mole less than in mononitroamines.3.Nitrogen dioxide and acetaldehyde do not influence the kinetics of thermal decomposition of dinitroamines due to their high reactivity.

Synthesis and physicochemical properties of cis- and trans-oxolane-3,4-diol derivatives

ConclusionsPhysicochemical properties of oxolane-3,4-diols, their dinitrates, diacetates, and ditosylates have been determined; the standard enthalpies of combustion and formation have also been measured for the first two series of derivatives.

Nitration equilibrium in the meso-erythritol-aqueous nitric acid system

Twelve equilibrium constants have been measured from 16 for sequential-parallel reactions in meso-erythritol nitration to the fully nitrated compound in aqueous HNO3. Free-energy changes during nitration of the aliphatic polyatomic alcohols, glycerol and meso-erythritol, are highest when diprimary dinitrates (NOON) and (NON) are produced.

Nitration equilibrium of water-soluble carboxycellulose

Maximum and minimum values of the equilibrium constants for nitration of hydroxyl groups in water-soluble carboxycellulose (WSCC) have been estimated. Electronegative substituants and elements of the cellulose structure in the WSCC molecule substantially lower the equilibrium constants for nitration compared with those for polyatomic aliphatic alcohols.

SYNTHESIS AND THERMOCHEMICAL PROPERTIES OF SOME FLUORINE-CONTAINING FORMALS

Fluorination of bis(2-fluoro-2,2-dinitroethyl) and bis(2,2,2-trinitroethyl) thionocarbonates by elemental fluorine gave bis(2-fluoro-2,2-dinitroethyl) and bis(2,2,2-trinitroethyl) difluoroformals. The reaction of 2,2,2-trinitroethyl nitrate with 2-fluoro-2,2-dinitroethyl chloromethyl ether gave 2-fluoro-2,2-dinitroethyl 2′,2′,2′-trinitroethyl formal. The standard heats of combustion and formation of the synthesized formals were determined by combustion in a calorimetric bomb. Increments of substitution of the trinitromethyl group by the fluorodinitromethyl group and of the H atom by F in the methylene group for formals were calculated and recommended for rough calculations. It was shown that it is possible to evaluate ΔHf0 of the formals by the method of increments and group contributions.