N. N. Aleinikov

Synthesis of pyridines with fluoro-containing superlipophilic substituents

Abstract Methods have been developed for the introduction of superlipophilic groups into the pyridine molecule via the polychloropyridine thiols (PCPT, 1) reaction with fluorogenated inorganic oxidizers (XeF2, IF5). Under the action of XeF2 in perfluoro-carbonic acid PCPT undergoes perfluoroalkylation to form 4-per-fluoroalkylthio-PCP (2) in 50–85% yields; oxidation products formed in aqueous HF are sulphofluorides PCP (3 and 4). PCPT when heated with IF5 involves fluorination of the SH group to form 4-pentafluorothio-PCP in 30–40% yields. Interaction of compounds (2) and (5) various nucleophilic agents has been studied. It is shown that the SRF and SF5 groups are easily substituted by 0 and S-bearing nucleophiles and are stable to a range of nitrogenated nucleophiles. A number of compounds with high biological activity have been developed.

Reaction of polyhalopyridines 4. Reaction of mercaptopolychloropyridines with fluorine-containing xenon compounds

A method has been developed for the perfluoroalkylation of mercaptopolychloropyridines by the thermolysis of xenon(II) perfluoroalkanecarboxylates, obtained by the reaction of xenon difluoride and aperfluoroalkanecarboxylic acids, in the presence of the appropriate thiol. Perfluoroalkylthio derivatives of polychloropyridines have been synthesized. The fluorosulfonyl derivatives of tetrachloropyriidne and of tetrachloropyridine N-oxide were obtained by the action of XeF2 on mercaptotetrachloropyridine dissolved in aqueous HF.

Nucleophilic reactions of 4-perfluoroalkylthiotetrachloropyridines

Abstract Earlier we reported on the synthesis of 4-perfluoroalkylthiotetrachloropyridines ( 1 ) by means of the perfluoroalkylating agents perchloropyridine thiols [A. M. Sipyagin, I.A. Pomytkin et al., J. Fluor. Chem., 54 (1991) 115]. In seeking new preparations possessing a range of useful properties we have studied reactions of 1 with various nucleophilic agents, and succeeded in synthesizing a number of new fluorocontaining derivatives. It was found that perfluoroalkylthio groups which are readily replaced by O - and S -nucleophilic agents are more stable to the action of N -nucleophiles and in this respect they surpass chlorine atoms in the 4 position of the pyridine ring.

Rate measurements for the reaction of H-atoms with the xenon and krypton fluoride molecules.

Abstract Elementary strongly exothermic reactions of H-atoms with the F 2 , KrF 2 , XeF 2 , XeF 4 , XeF 6 molecules useful for chemical lasers have been investigated by mass-spectrometric probing of the diffusion cloud in flow [1] . Some ionisation and appearance potentials were defined [2] from experimental ionization efficiency curves. Arrhenius expressions were obtained for the rate constants between 298–505 K. They correspond to an activation energy of 8.9± 0.6; 11.3±0.2; 21.8±2; 22.6±5; 28.5±3.8 kj/mol for the H + F 2 , KrF 2 , XeF 2 , XeF 4 , XeF 6 reactions respectively, with the preexponential factor near 10 −10 cc/molec-c for all rate constants. It was established that HF product of the H+F 2 “model” reaction is excited up to 8-th vibrational level while such one of the H+ KrF 2 reaction is not vibrationally excited. Thus a second product of H+KrF 2 reaction may be eximer KrF(B 2 Σ) with the energy excitation 481.3 kJ/mol which corresponds to sum of the reaction heat and activation energy.

Thermal Decomposition of Xenon Tetroxide at 490–780 K

The decomposition of XeO4 was studied over the temperature range 490–780 K. A reaction mechanism was proposed. A conclusion on the high vibrational excitation of O2 molecules formed in the elementary reaction O + XeO4 → O2 + XeO3 and the branched-chain character of the decomposition with branching in the reaction O + XeO3 → 2O + O2 + Xe was drawn.

Kinetics and Mechanism of the Reaction of Xenon Tetroxide with Carbon Disulfide

The dependence of the rate of the reaction of XeO4with CS2on the concentrations of reactants and diluent gases He, O2, and CO2was studied at room temperature. A reaction mechanism was proposed.

Mechanism of the Reaction of Xenon Tetraoxide with Hydrogen: A Photochemical Reaction

AbstractThe dependence of the rate of a photochemical reaction of XeO4with H2on the concentrations of H2and the diluent gases He and CO2is studied at room temperature. The results are compared with the data for the dark reaction. A mechanism with the elementary energetic branched-chain reaction OH

BIS(TETRAMETHYLAMMONIUM), BIS(TETRABUTYLAMMONIUM), AND BIS(TETRAPHENYLARSONIUM) DIHYDROHEXAOXOXENONATES(VIII)

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