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Two new Schiff base compounds of N‐{2‐[(E)‐сyclohexyliminomethyl]phenyl}‐4‐methylbenzenesulfonamide, N‐{2‐[(E)‐(4‐сyclohexylphenyl)iminomethyl]phenyl}‐4‐methylbenzenesulfonamide and their Zn(II) complexes have been synthesized and characterized by elemental analysis, FT‐IR and UV–Vis spectra, and single crystal X‐ray determination. In both complexes, Zn2+ ions have a tetrahedral environment with two nitrogen atoms of the tosylamide groups and two nitrogen atoms of the imine fragment. Time‐dependent density functional theory calculations have been performed on two zinc(II) complexes in order to assign their experimental UV–visible absorption bands. Zinc(II) complexes showed thermal stability up to 335–340°C under a nitrogen atmosphere by thermogravimetric analysis (TGA). The photoluminescent spectra show that both Zn(II) complexes in the solid state at room temperature emit blue luminescence with high emission quantum yields of 20% and 29%. The doped devices with configurations of indium tin oxide (ITO)/poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/N,N′‐Di(1‐naphthyl)‐N,N′‐diphenyl‐(1,1′‐biphenyl)‐4,4′‐diamine (NPD)/4,4′‐N,N′ ‐dicarbazolebiphenyl (CBP):Zinc(II) complex (5%)/1,3,5‐tris(N‐phenylbenzimidazole‐2‐yl) benzene (TPBI)/LiF/Al have been fabricated and investigated. The doped device based on the complex with the сyclohexylphenyl substituent of the ligand showed the best electroluminescent characteristics with maximum brightness Lmax of 3415 cd/m2, maximum current efficiency of 2.8 cd/A, and power efficiency of 1.9 lm/W, while the doped device with emitter on the base of the complex with the сyclohexyl substituent showed slightly worse electroluminescence (EL) performance with Lmax of 2105 cd/m2, maximum current efficiency of 2.1 cd/A, and power efficiency of 1.6 lm/W. [ABSTRACT FROM AUTHOR]

Research has been conducted on the nitrile complexes and benzohydroxamic acids. Results indicate that the reaction between these compounds carried out in CH (sub)2 Cl (sub)2 and under microwave irradiation gives imino complexes derived from the metalla-Pinner reaction.

Research has been conducted on organonitrile platinum(IV) complexes. Results indicate that the addition of MeOH or EtOH to these complexes occures under mild conditions and does not require a base as a catalyst.

New Zn(II) complexes of bidentate Schiff base ligands were synthesized and characterized by 1H NMR, IR spectroscopy, and elemental analysis. The single‐crystal X‐ray diffraction study revealed that all compounds can be represented as mononuclear zinc(II) complexes with two bidentate organic ligands coordinated to the central metal atom by two oxygen and two nitrogen atoms. The photophysical properties of the complexes were investigated by UV–vis and photoluminescence spectroscopy in dimethyl sulfoxide (DMSO) solutions. It was found that the positions of maxima of the long‐wavelength absorption bands and photoluminescence depend strongly on the substituent in the aldehyde and amine fragments. The nature of the bands of electronic absorption spectra in DMSO solutions was interpreted using the results of quantum chemical calculations in the time‐dependent density functional theory (TD‐DFT) approximation. The light emission performance of the complexes in organic light‐emitting diodes was investigated. The electroluminescence (EL) spectra maxima of all three complexes are located in the visible range from 470 to 550 nm. The absence of additional spectral maxima or shoulders in the EL bands means that neither exciplex nor excimer states form, and the observed EL bands are due to the intrinsic radiation of the zinc(II) complexes. EQEs were measured for these three complexes. The maximum value, close to 3%, was obtained in the case of a structure with a maximal brightness of 8000 cd m−2 at 17 V. [ABSTRACT FROM AUTHOR]

Research has been conducted on platinum(IV) complex. The reactions between this complex and amino alcohols has been carried out at room temperature in order to produce amidine complexes, and the details are presented.

A series of Zn(II) complexes of the tridentate azomethine ligands, condensation products of 2‐(N‐tosylamino)benzaldehyde and 2‐aminoalkylpyridines, were synthesized by chemical and electrochemical methods. All compounds were characterized on the basis of C, H, N elemental analysis, Fourier‐transform infrared, 1H nuclear magnetic resonance, UV–Vis, and photoluminescence studies. The local atomic structures of complexes were determined from analysis of extended X‐ray absorption fine structure and X‐ray absorption near‐edge structure of Zn K‐edges. The molecular structure of chloro‐{4‐methyl‐N‐[2‐[(Z)‐2‐pyridyl)ethyliminomethyl]phenyl]benzenesulfamide}zinc(II) was determined by X‐ray single‐crystal diffraction. The fluorescence spectra show that these complexes in dimethyl sulfoxide solutions at room temperature emit bright blue luminescence at 435–461 nm with fluorescence quantum yields in the range of 0.20–0.31. The assignment and the nature of the bands in experimental UV–Vis spectra of complexes were analyzed using time‐dependent density functional theory calculations B3LYP/6‐31G(d). The azomethines and complexes of zinc have been screened for their antibacterial, protistocidal, and fungistatic activities against Penicillium italicum, Colpoda steinii, Escherichia coli 078, and Staphylococcus aureus P‐209, and the results are compared with the activity of furazolidone, chloroquine, and Fundazol. [ABSTRACT FROM AUTHOR]