The Electroluminescence Spectra of Light-Emitting Devices Based on Zinc Complexes of Amino-Substituted Ligands

Exciplex bands in the electroluminescence (EL) spectra of electroluminescent devices based on the new zinc complexes of amino-substituted benzothiazoles and in the photoluminescence (PL) spectra of the blends of a zinc complex and the triphenylamine derivative are studied. For the EL spectra, it is found that the relation between the exciplex bands and the intrinsic bands of the zinc complex emission depends on the thickness of layers in the EL devices and on the applied voltage. For the PL spectra of blends, this relation strongly depends on the concentration of components.     

Properties and structure of oxidized coatings deposited onto Al-Cu and Al-Mg alloys

The results of new studies of creating protective oxide coatings based on Al₂O₃ (Si, Mn) and deposited onto aluminum alloys using electrolyte-plasma oxidation are presented. An analysis is performed by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), X-ray diffraction, Rutherford backscattering of ⁴He⁺ and protons, nanoindentation, scratching, friction coefficient measurements, and acoustic emission measurements. The results demonstrate that the deposited coatings have a high quality, hardness, and wear resistance and a low thermal diffusivity. Apart from Al₂O₃, the coatings are found to have Si, Mn, C, and Ca. The stoichiometry of the coatings is determined. The density and hardness of the coatings are close to those of ??-Al₂O₃ in the coating on an Al-Cu (D-16) substrate, and these values of the coating on an Al-Mg (S006) are lower by a factor of 1.5.     

A new class of electroluminescent metal complexes based on quinoline ligands containing the sulfanylamino group

The synthesis and properties of a new class of electroluminescent metal complexes based on quinoline ligands containing the sulfanylamino group in position 8 are described. These complexes contain C-N-M-N chains in the chelate cycles instead of the traditionally used C-O-M-N chains.     

Electrical conductivity and photoconductivity of films of composites based on poly[2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylenevinylene] with additions of zinc octabutyl phthalocyanine and C60

Features of the photoconductivity of films of composites based on [2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylenevinylene] with additions of zinc 2,3,9,10,16,17,23,24-octabutylphthalocyanine and C₆₀ were studied. Luminescence quenching and an increase in the photoconductivity with the addition of C₆₀ to their composition were detected. The increase in the photoconductivity is connected with the capture of electrons and their transport along the C₆₀ molecules. __________ Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 42, No. 5, pp. 271–275, September–October, 2006.     

Chemoselective Staudinger‐Phosphite Reaction on the Azido Groups of 2,4,6‐Triazido‐3,5‐dibromopyridine

2,4,6‐Triazido‐3,5‐dibromopyridine reacts with an equimolar amount of triethyl phosphite in ether at room temperature chemoselectively on the γ‐azido group to form 2,6‐diazido‐3,5‐dibromo‐4‐triethoxyphosphoriminopyridine as a single product. The latter adds another molecule of triethyl phosphite to give a mixture of 6‐azido‐2,4‐bis(triethoxyphosphorimino)‐3,5‐dibromopyridine and its tetrazolo[1,5‐a]pyridine isomer, the acidic hydrolysis of which affords 6‐azido‐2,4‐bis(diethoxyphosphoramino)‐3,5‐dibromopyridine. The study shows that the Staudinger‐phosphite reactions with heterocyclic polyazides occur selectively on the most electron‐deficient azido groups, opening up new prospects for preparation of new polyfunctional heterocyclic compounds.     

High-spin organic molecules with dominant spin-orbit contribution and unprecedentedly large magnetic anisotropy

High-spin organic molecules with dominant spin-orbit contribution to magnetic anisotropy are reported. Quintet 4-azido-3,5-dibromopyridyl-2,6-dinitrene (Q-1), quintet 2-azido-3,5-dibromopyridyl-4,6-dinitrene (Q-2), and septet 3,5-dibromopyridyl-2,4,6-trinitrene (S-1) were generated in solid argon matrices by ultraviolet irradiation of 2,4,6-triazido-3,5-dibromopyridine. The zero-field splitting (ZFS) parameters, derived from electron spin resonance spectra, show unprecedentedly large magnitudes of the parameters D: ∣D(Q1)∣ = 0.289, ∣D(Q2)∣ = 0.373, and ∣D(S1)∣ = 0.297 cm(-1). The experimental ZFS parameters were successfully reproduced by density functional theory calculations, confirming that magnetic anisotropy of high-spin organic molecules can considerably be enhanced by the "heavy atom effect." In bromine-containing high-spin nitrenes, the spin-orbit term is dominant and governs both the magnitude and the sign of magnetic anisotropy. The largest negative value of D among septet trinitrenes is predicted for 1,3,5-trinitrenobenzene bearing three heavy atoms (Br) in positions 2, 4, and 6 of the benzene ring.     

Electrochemical Properties of Nanocomposite Based on Polytriphenylamine Derivative and Single-Walled Carbon Nanotubes

One-step synthesis of the stable dispersion of conjugated poly(4,4',4"-tris(N,N-diphenylamine) triphenylamine)—single-walled carbon nanotubes nanocomposite is carried out by the oxidative polymerization of the monomer of the triphenylamine derivative with a high density of free radicals of 4,4',4"- tris(N,N-diphenylamine)tripenylamine in the presence of the single-walled carbon nanotubes in concentrated formic acid. Benzoyl peroxide is used as an oxidant. Electroconductive film coatings are prepared by applying stable dispersion onto the Ni substrate. The coatings show a high specific electrochemical capacity and stability in long-term cycling in the aprotic 1 M LiClO₄/propylene carbonate electrolyte.

     

Synergistic antitumor effect of cisplatin and the platinum(iv) nitroxyl complex BC118 and the development of resistance to their combined action

The efficacy of the combination treatment of P388 leukemia with cisplatin (cPt) and the platinum(IV) nitroxyl complex BC118 [e-ammine-d-(4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl)-a,f-bis(acetato)-b,c-dichloroplatinum(iv)] applied in low doses was found to be synergistically increased. Thus, the use of 1/10 of their LD₅₀ cured 100% of animals. The monotherapy with these drugs used in the same doses and at the same schedules showed moderate efficacy, and no animals survived. A synergistic increase in the toxicity was not observed. The rate of the development of resistance decreases in the series cPt+BC118, cPt, and BC118. Strains resistant to cPt+BC118 and BC118 are highly sensitive to doxorubicin, etoposide, and cyclophosphane.     

Synthesis,characterization, and antileukemic activity of new water-soluble analogs of prodimin

Russian Chemical Bulletin - Two new compounds from the class of bis(3-halopropionyl)amides were synthesized by the reaction of 3-halopropionyl chloride with N,N′-dimethylethylenediamine....