Synthesis of 2-Substituted 6-(Polyfluoromethyl)pyrimidine-4-carbaldehyde Acetals

Russian Journal of Organic Chemistry - Heterocyclization of 5,5-difluoro- and 5,5,5-trifluoro-2,4-dioxopentanal dimethyl acetals with amidines in the presence of 4 equiv of triethyl borate afforded...     

An efficient synthetic approach towards new 5, 5'-diaryl-2, 2'-bipyridine-based fluorophores

An efficient approach has been developed for the synthesis of 5,5'-diaryl-2,2'-bipyridines via their 1,2,4-triazine analogues. The notable advantages of the present method are:The possibility of varying the aromatic substituents in the positions 5 and 5' of bipyridine core and the possibility for obtaining 2,2'-bipyridines bearing a fused cyclopentene core to increase the solubility in organic solvents. These 5,5'-diaryl-2,2'-bipyridines exhibited an intense emission in a range of ca. 422-521 nm in acetonitrile solution; depending on the nature of the aromatic substituents and the presence of annulated cyclopentene fragments. Apart from that, the significant bathochromic shifts of the both absorption and emission maxima were observed in comparison with a number of previously described similar structures. In some cases the significant increasing of the fluorescence quantum yields took place.     

DANSS Neutrino Spectrometer: Detector Calibration,Response Stability,and Light Yield

Apart from monitoring nuclear reactor parameters, the DANSS neutrino experiment is aimed at searching for sterile neutrinos through a detailed analysis of the ratio of reactor antineutrino spectra measured at different distances from the reactor core. The light collection system of the detector is dual, comprising both the vacuum photomultiplier tubes (PMTs) and silicon photomultipliers (SiPMs). In this paper, the techniques developed to calibrate the responses of these photodetectors are discussed in detail. The long-term stability of the key parameters of the detector and their dependences on the ambient temperature are investigated. The results of detector light yield measurements, performed independently with PMTs and SiPMs are reported.     

X-Ray Diffraction Structural Studies of a Series of 4-Aryl-1-di- and 4-Aryl-1-trichloromethylisoquinolines and Their 1,2,4-Triazine Precursors

Russian Journal of General Chemistry - Structure of two 4-aryl-1-trichloromethylisoquinolines as well as 3-dichloromethyl-6-phenyl-1,2,4-triazine (a synthetic precursor of the corresponding...     

Synthesis of substituted 4,4´-dihalobiphenyls and their use for the preparation of isomeric bis(carbazolyl)biphenyls

Model compounds of some polychlorobiphenyl congeners, viz., 4,4´-dihalobiphenyls, were synthesized. These compounds can be successfully utilized by a chemical method for the in situ generation of arynes followed by the reaction with carbazole in order to prepare appropriate bis(carbazolyl)biphenyls as components for molecular electronics and OLED devices.

     

Synthesis and research of electrochemical behavior of magnetic nanocomposites based on Fe3O4

The nanocomposites including magnetite nanoparticles, polymer coating and electrochemically active molecules were synthesized and investigated: poly(vinylbenzyl) chloride coating modified by quinoline; coating based on polypyrrole, silica coating modified by ferrocene derivative. All samples were investigated by the cyclic voltammetry method.     

Stable σH-adducts in the reactions of the acridinium cation with heterocyclic N-nucleophiles

A reaction of NH-heterocycles with the 10-methylacridinium cation in the presence of a base led to 9,10-dihydro-10-methyl-9-substituted acridines, which can be considered as stable intermediates in the aromatic nucleophilic substitution reaction of hydrogen. The structure of the intermediates was studied and their oxidation potentials were determined. Generally, the oxidation potential was found to symbatically change with the changes in the energy of HOMO.