Tetrasubstituted Peropyrenes Formed by Reductive Aromatization: Synthesis,Functionalization and Characterization

The chromophore class of 1,3,8,10-tetrasubstituted peropyrenes was effectively synthesized from peropyrenequinone via a Zn-mediated reductive aromatization approach. In one step, a symmetric functionalization of the peropyrene backbone introducing silylethers ( 2 , 3 ), pivaloyl ( 4 ), triflyl ( 5 ) and also phosphinite ( 6 ) groups was established. Furthermore, the potential of using 4 and 5 in transition metal catalysed cross couplings was explored leading to 1,3,8,10-tetraaryl ( 8 - 11 ) and tetraalkynyl ( 7 ) peropyrenes. The influence of various substituents on the optoelectronic properties of these π-system extended peropyrenes was investigated in solid state by means of X-ray crystallography, in solution by means of UV-Vis and fluorescence spectroscopy and by their redox properties studied via cyclic voltammetry. By comparison with DFT and TD-DFT calculations, it could be elucidated that introduction of a broad variety of substituents in such versatile one or two step procedures leads to peropyrenes with easily tunable HOMO and LUMO energies ranging in a gap window of 0.8 eV. The frontier molecular orbital energies identify the target molecules as promising candidates for hole transporting semiconductors.     

A Comprehensive Study on the Full Series of Alkali-Metal Selenocyanates AI[SeCN] (AI=Li−Cs)

The full series of quasibinary alkali-metal selenocyanates was synthesized either by oxidation of the respective cyanides (A=Li−Rb) or by metathesis (A=Cs). For Li[SeCN] only ball-milling and subsequent annealing led to the isolation of the quasibinary selenocyanate. Their structures were refined from single-crystal and powder X-ray data. The respective solid-state IR and Raman spectra were interpreted with the aid of solid-state quantum-mechanical calculations and DSC-TGA measurements allowed for extraction of melting points. Only for Li[SeCN] a possible phase transition was observed that is discussed on the basis of VT-PXRD experiments. It is also the only quasibinary selenocyanate to form a hydrate (Li[SeCN] ⋅ 2H₂O).     

Synthesis and Conductivity of Bismuth Molybdates Doped with Antimony and Tin

Russian Journal of Electrochemistry - The possibility of synthesizing oxygen-ion conductors based on bismuth molybdate with antimony and tin substituted to the molybdenum sublattice is studied and...     

Synthesis,structure, and properties of 2-[(4,6-di-tert-butyl-2,3-dihydroxyphenyl)thio]acetic acid amides

Russian Chemical Bulletin - New potential biologically active derivatives, in which the sterically hindered pyrocatechol moiety is linked through a 2-thioacetyl covalent bridge to a number of...     

Synthesis and biological properties of novel structural analogs of isothiobarbamine

Russian Chemical Bulletin - Novel structural analogs of isothiobarbamine, which differ from the prototype scaffold by the substituent at position 2 of the pyrimidine heterocycle, were for the first...     

Kinetic regularities of thermal decomposition of polycarbonate films containing Pt,Au, Ag,and Ni nanoparticles

Russian Chemical Bulletin - The kinetic regularities of thermal destruction of polycarbonate films containing Pt, Au, Ag, and Ni nanoparticles were studied. Scanning and transmission electron...     

Specific features of coupling reactions of polystyrene in the presence α-dinitrones based on glyoxal

Russian Chemical Bulletin - Bromine-containing polystyrene synthesized by atom transfer radical polymerization was used as a model to study coupling reactions in the presence of such free radical...     

Determination of Indicator Congeners of Polychlorinated Biphenyls in Water at Ultratrace Levels by Gas Chromatography–Tandem Mass Spectrometry

Journal of Analytical Chemistry - We validated a procedure for the determination of indicator congeners (ICs) of polychlorinated biphenyls (PCBs) (IUPAC nos. 28, 52, 101, 118, 138, 153, and 180) in...     

Molecular design of multitarget neuroprotective agents 5. Modification with pharmacologically active fragments of 4,4- and 1,4-dipropargyl-5-methyl-2-phenylpyrazol-3-one

Russian Chemical Bulletin - A synthetic approach to the modification of the drug Edaravone with pharmacoactive moieties of adamantane, carbazole, tetrahydrocarbazole, and γ-carboline was...     

Molecular Simulations of CO2/CH4, CO2/N2 and N2/CH4 Binary Mixed Hydrates

Colloid Journal - Grand canonical Monte Carlo simulations were performed to study the occupancy of structure I multicomponent gas hydrates by CO2/CH4, CO2/N2, and N2/CH4 binary gas mixtures with...