2-Propenyl-(2-methyl-1-propenyl-, 2-butenylthio- and (3-methylbutenyl-)thio4,5-dihydro-1,3-thiazoles are synthesized by alkylation of 4,5-dihydro-1,3-thiazol2-thione. These products were researched in halocyclization reactions with iodine and bromine.3-(halomethyl)-2,3,5,6-tetrahydrothiazolo[2,3-b]thiazolium and 6-halo-3,5,6,7-tetrahydro-2H-thiazolo[2,3-b]thiazinium halides were formed. The structure of all the synthesized compounds was confirmed by 1H NMR and gas chromatography-mass spectrometry.
The palladium complex [Ph 3PCH=CHPPh 3] 2+[PdBr 3∙DMSO] - 2∙DMSO (1) has been synthesized by the reaction of palladium dibromide with 1,2-vinylene-bis-triphenylphosphonium dibromide in the presence of hydrobromic acid in water, followed by recrystallization from dimethylsulfoxide. According to the X-ray diffraction data, the phosphorus atoms in cations have a slightly distorted tetrahedral environment (CPC 107.8(3)°-111.7(3)° Å), the P-С bond lengths are 1.779(6)-1.816(5) Å. In the square planar anions, the SPdBr trans-angles are 176.89(5)° and 178.11(6)° Å, and the BrPdBr trans-angles are 177.59(4)° and 177.82(3)° Å. Dimethylsulfoxide ligands are coordinated to the Pd atoms by the sulfur atoms: the Pd-S bond lengths are 2.2634(17) and 2.2666(18) Å, the Pd-Br bond lengths lie in the range of 2.4200(18)-2.4486(9) Å. Structural organization of the crystal is caused by the interionic H∙∙∙Br (2.90-3.02 Å) and H∙∙∙O (2.30-2.56 Å) hydrogen bonds.
REACTIONS OF TRI( ORTHO-TOLYL)- AND TRI( META-TOLYL)ANTIMONY WITH OXIMES IN THE PRESENCE OF AN OXIDANT. THE STRUCTURES OF TRI( ORTHO-TOLYL)- AND TRI( META-TOLYL)ANTIMONY DIOXIMATES
The triarylantimony dioximates: ( о-СH 3C 6H 4) 3Sb(ON=CHC 6H 4N(CH 3) 2-4) 2 (1), ( о-СH 3C 6H 4) 3Sb(ON=CMePh) 2 (2), ( m-СH 3C 6H 4) 3Sb(ON=CHC 4H 3O) 2 (3) were obtained from the reactions of tri( ortho-tolyl)antimony and tri( meta-tolyl)antimony with appropriate oximes in the presence of hydrogen peroxide and tert-butyl hydroperoxide. According to the X-ray analysis data, antimony atoms are bound to oxygen atoms of axial oximate ligands in the trigonal bipyramidal coordination in molecules 1-3. The peculiarities of molecular structures are short intramolecular contact Sb∙∙∙N, which is 1 Å less than the sum of Van der Waals radiuses.
THE STUDY OF GROUNDWATER QUALITY OF SCIENTIFIC AND PRODUCTION CENTER OF THE SOUTH FORESTRY IN ILMENSKY STATE RESERVE
Krupnova T.G., Mashkova I.V., Kostryukova A.M., Scalev E.D.
The present work deals with the quality of groundwater used for water supply of the scientific and production center of the South forestry in Ilmensky State Reserve. Chemical analyses of water from three wells have been conducted. The relationship of the quality of surface water and groundwater has been investigated. Anthropogenic causes of the variation of drinking water quality from the existing guidelines have been identified.
STRUCTURE OF LITHIUM PYROSILICATE MELTS ACCORDING TO DATA OF HIGH-TEMPERATURE RAMAN SPECTROSCOPY
Koroleva O.N., Mosunova T.V.
Decomposition of the high-frequency range of Raman spectra for 60Li 2O·40SiO 2 melts (Li60) into the Gaussian line shape was performed. The basic structural fragments of melts and their ratio were determined, and the peculiarities of their interaction with the change in temperature were identified.
FORMATION (DECOMPOSITION) ENTHALPY CALCULATIONS FOR CRYSTAL LATTICES OF ALKALINE-EARTH FLUORIDES
Gruba O.N., Germanyuk N.V., Ryabukhin A.G.
A series of calculations of structural and thermochemical properties has been carried out for the alkaline-earth fluorides. The calculations have been carried out using the modified model of effective ionic radii and the model of enthalpy calculation for the crystal lattice. The results of the calculations are in accordance with the known experimental data within confidence intervals.
COMPARATIVE ANALYSIS OF THEORETICAL AND EXPERIMENTAL UV-SPECTRA OF 2- AND 8-THIOQUINOLINE
Matveychuk Yu.V., Ilkaeva M.V., Krivtsov I.V., Bartashevich E.V.
The comparative analysis of the calculated electronic absorption spectra of various forms of 2- and 8-thioquinoline and the experimental UV spectra of their solutions in various solvents has been carried out. Two conformational isomers of SH-forms have been analyzed for each compound. Calculations of other tautomeric forms of these compounds, namely NH-forms of 2-thioquinoline (2-thioquinolone) and 8-thioquinoline (zwitter-ion), and S-forms (anions) and 1-H-2-thioquinolinium cation have been analyzed additionally. It is shown that the absorption bands in the spectrum of 8-thioquinoline solution correspond to the electronic transitions in the SH-tautomer. On the contrary, the absorption bands in a spectrum of 2-thioquinoline solution correspond to the electronic transitions in the NH-tautomer and S-anion. The spreading of absorption bands in the experimental spectra is associated with conformational and tautomeric equilibrium which is established in the solutions of the considered compounds.