G. V. Oreshko

Synthesis and structure of nitro derivatives of pentane. Communication 2. 1,1,1,3,5,5,5-Heptanitropentane and its 3-fluoro and 3-chloro derivatives

Conclusions1.The compound 1,1,1,3,5,5,5-heptanitropentane has been prepared, and from this, 3-fluoro-1,1,1,3,5,5,5-heptanitropentane has been synthesized.2.By means of x-ray structure analysis, a closed-chain conformation of the carbon atoms has been established for 1,1,1,3,5,5,5-heptanitropentane, 3-fluoro-1,1,1,3,5,5,5-heptanitropentane, and 3-chloro-1,1,1,3,5,5,5-heptanitropentane.3.Calculations of the electronic structure of all three compounds showed that the 3-chloro-1,1,1,3,5,5,5-heptanitropentane is more strongly polarized, and this should lead to an increase in the electrostatic intermolecular interaction in the crystal. The distribution of averaged contacts of different types in the crystals of these compounds corresponds to their electronic structure.

Synthesis and fluorination of nitro-substituted thionocarbonates

Thiocarbonylchloride reacts with β-nitroalcohols yielding symmetrical thionocarbonates. Transesterification of bis(2-fluoro-2,2-dinitroethyl)thioncarbonate affords alkyl 2-fluoro-2,2-dinitroethylthionocarbonates. Fluorination of these thionocarbonates yields the corresponding difluoroformals.

Difluorination of mononitrocompounds with elemental fluorine

The difluorination of fluorodinitromethane, 2-fiuoro-2-nitroethanol, and ethyl 2-fluoro-2-nitroacetate has been carried out to yield difluoronitromethane, 2,2-difiuoro-2-nitroethanol, and ethyl 2,2-difluoro-2-nitroacetate.

Synthesis and structures of nitroxyalkyl methylphosphonates

The reactions of ethylene glycol mononitrate and glycerol 1,3-dinitrate with methylphosphonic dichloride afforded new nitroxyalkyl methylphosphonates.

NMR study on the interaction of 1,4-cubanedicarboxylic acid and its esters with elemental fluorine. The synthesis of dimethyl 2-fluorocubane-1,4-dicarboxylate

Elemental fluorine can be successfully used for fluorination of cubane derivatives. The nature of the products depends on the fluorination conditions: in CH3CN at -20 to -30 degrees C, dimethyl 2-fluorocubane-1,4-dicarboxylate was obtained from dimethyl ester of 1,4-cubanedicarboxylic acid; in CF3COOH at -12 to -15 degrees C in the presence of alkali metal acetates, 1,4-cubanedicarboxylic acid and its dimethyl and diethyl esters gave complex mixtures of fluorinated cubane products. Our investigation by 1H and 19F NMR spectroscopy and spectra computer simulation revealed production of mono- and difluorinated cubanes. Fluorine-containing cubane derivatives were also found with extra substituents in other than 1 and 4 positions.

Synthesis and structure of nitro derivatives of pentane. Communication 1. 3-fluoro and 3-nitro derivatives of 1,5-difluoro-1,1,3,5,5-pentanitropentane

Conclusions1.1,5-Difluoro-1,1,3,3,5,5-hexanitropentane and 1,3,5-trifluoro-1,1,3,5,5-pentanitropentane have been prepared.2.By means of x-ray structure analysis, we have found a branched conformation of the 1,5-difluoro-1,1,3,3,5,5-pentanitropentane.3.The 1,5-difluoro-1,1,3,3,5,5-hexanitropentane has a more uniform charge distribution in comparison with the 1,3,5-trifluoro-1,1,3,5,5-pentanitropentane. The nonuniform charge distribution with respect to the terminal contacting atoms in the latter compound leads to electrostatic intermolecular interaction, and as a result, to a looser packing in comparison with the other compound.

Salts of symmetric polynitropentanes and their reactions with halogens

Conclusions1.The reaction of 1,1,1,3,5,5,5-heptanitropentane and 1,5-difluoro-1,1,3,5,5-pentanitropentane in a nonpolar medium at a reduced temperature yields the ammonium, pyridinium, and anilinium salts of the polynitropentanes indicated.2.The ability of the ammonium and pyridinium salts of 1,1,1,3,5,5,5-heptanitropentane and 1,5-difluoro-1,1,3,5,5-pentanitropentane to undergo chlorination and bromination to form the corresponding 3-chloro- and 3-bromo derivatives and of the ammonium salt of 1,5-difluoro-1,1,3,5,5-pentanitropentane in water to undergo fluorination to 1,3,5-trifluoro-1,1,3,5,5-pentanitropentane has been demonstrated.

Synthesis of halo-substituted sym-polynitropentanes

ConclusionsThe fluorination, chlorination, and bromination of the 1,1,1,3,5,5,5-heptanitropentane and l,5-difluoro-1,1,3,5,5-pentanitropentane ions gave the corresponding 3-halo derivatives.

Esterification of carboxylic acid derivatives with 2-fluoro-2,2-dinitroethylsulfuric acid

The reaction of carboxylic acid anhydrides, acid halides, esters and salts with 2-fluoro-2,2-dinitroethyl sulfuric acid is a general method for preparing esters of 2-fluoro-2,2-dinitroethanol.