Zinc Complexes of Fluorosubstituted N-[2-(Phenyliminomethyl)phenyl]-4-methylbenzenesulfamides: Synthesis, Structure, Luminescent Properties, and Biological Activity.

Mono-, di-, and trifluorophenyl substituted in different positions of amine fragments bis [2-[[(E)-((fluorophenyl)iminomethyl]-N-(p-tolylsulfonyl)anilino]zinc(II) complexes were synthesized. Their crystal structure, photo- and electroluminescent properties, and protistocidal, fungistatic, and antibacterial activities were studied. It has been shown that the introduction of fluorine atoms and an increase in their number in the ligand structure of the resulting metal complexes promote the luminescence quantum yields and values of performance and brightness in EL cells compared to their previously studied chlorine-substituted analogs.

Synthesis, Structure, Spectral-Luminescent Properties, and Biological Activity of Chlorine-Substituted N-[2-(Phenyliminomethyl)phenyl]-4-methylbenzenesulfamide and Their Zinc(II) Complexes.

New azomethine compounds of 2-(N-tosylamino)benzaldehyde or 5-chloro-2-(N-tosylamino)benzaldehyde and the corresponding chlorine-substituted anilines, zinc(II) complexes based on them have been synthesized. The structures of azomethines and their complexes were determined by elemental analysis, IR, 1H NMR, X-ray spectroscopy, and X-ray diffraction. It is found that all ZnL2 complexes have a tetrahedral structure according to XAFS and X-ray diffraction data. The photoluminescent properties of azomethines and zinc complexes in methylene chloride solution and in solid form have been studied. It is shown that the photoluminescence quantum yields of solid samples of the complexes are an order of magnitude higher compared to the solutions and range from 11.34% to 48.3%. The thermal properties of Zn(II) complexes were determined by thermal gravimetric analysis (TGA) and differential scanning calorimetry. The TGA curves of all the compounds suggest their high thermal stability up to temperatures higher than 290 °C. The electrochemical properties of all complexes were investigated by the cyclic voltammetry method. The multilayered devices ITO/PEDOT:PSS/NPD/Zn complex/ TPBI/LiF/Al with wide electroluminescence (EL) color range spanning the range from bluish-green (494 nm) to green (533 nm) and the high values of brightness, current and power efficiency were fabricated. The biological activity of azomethines and zinc complexes has been studied. In the case of complexes, the protistocidal activity of the zinc complex with azomethine of 5-chloro-2-(N-tosylamino)benzaldehyde with 4-chloroaniline was two times higher than the activity of the reference drug toltrazuril.

Versatile coordination modes of bis[5-(2-pyridine-2-yl)-1,2,4-triazole-3-yl]alkanes in Cu(II) complexes.

Nine new mononuclear and polynuclear Cu(II) complexes [Cu(H2L(2))Cl]Cl·3H2O (1), [Cu(H2L(3))Cl]Cl·H2O (2), [Cu(H2L(4))Cl]Cl·2.5H2O (3), [Cu3(µ(3)-L(1))2(H2O)3](ClO4)2·H2O (4), [Cu4(µ-HL(1))4](ClO4)8·CH3OH·5H2O (5), [Cu2(HL(3))2](ClO4)2·2H2O (6a), [Cu2(µ-HL(3))2](ClO4)2·H2O (6b), [Cu2(µ-HL(3))(L(3))Cu(teta)](ClO4)3·2H2O (7) and [Cu2(H2L(3))2(ox)](ClO4)2·2H2O·2MeOH (8) containing [5-(2-pyridine-2-yl)-1,2,4-triazole-3-yl]alkanes (H2L(n), n = 1-4) in combination with other ligands, such as chlorido, aqua, triethylenetetramine (teta) and/or oxalato (ox(2-)), were synthesized and characterized by various techniques such as elemental analysis, FTIR, NMR and UV-Vis spectroscopy. X-ray structures of H2L(3) and H2L(4) as well as complexes 1-8 were determined. The X-ray structures revealed that relatively small composition and structural changes in the H2L(n) ligands have a substantial impact on the coordination geometries of the complexes themselves as well as on their resulting magnetic properties. It has been found that the geometries of the complexes vary from square-pyramidal to trigonal-bipyramidal (with τ ranging from 0.00 to 0.96) and, moreover, that the trigonal bipyramidal geometry becomes more preferable with the increase in the length of the polymethylene chain within the corresponding H2L(n) ligand. The magnetic properties of the polynuclear compounds 4, 5, 6, 7 and 8 were analysed using the spin Hamiltonian formalism, which revealed the presence of antiferromagnetic exchange in the polynuclear systems mediated by the title ligands. The significant effect of the geometric parameters on the Cu···Cu exchange interactions in the polynuclear complexes is discussed.

Spacer-armed copper(II) complexes with benzenecarboxylic acids and trifluoroacetylacetone aroylhydrazones.

New bi- and trinuclear copper(ii) complexes of aroylhydrazones of TFA and benzenecarboxylic acids were synthesized and characterized. Despite long range intramolecular CuCu distances of about 10 Å, exchange couplings between paramagnetic centres are observed with J values of 0.33 and 0.37 cm(-1) in binuclear complexes, and -0.33 cm(-1) in trinuclear complexes. Seven hyperfine peaks with a value of aCu = 37.0 × 10(-4) cm(-1) are observed in EPR spectra of binuclear complexes. The possible mechanisms responsible for the observed weak long range coupling via aromatic spacers are discussed.

Synthesis, structure and luminescence studies of Eu(III), Tb(III), Sm(III), Dy(III) cationic complexes with acetylacetone and bis(5-(pyridine-2-yl)-1,2,4-triazol-3-yl)propane.

Studies concerning synthesis, structure and luminescence of eight-coordinate Eu, Tb, Sm and Dy complexes of the type [Ln(acac)2(L)]Cl (Hacac = pentanedione-2,4 and L = bis(5-(pyridine-2-yl)-1,2,4-triazol-3-yl)propane) are reported in detail. The obtained complexes were investigated by various means including elemental- and thermogravimetric analysis, IR- and electron transition spectroscopy. The structure of the Tb complex was determined by single-crystal X-ray crystallography: Tb is eight-coordinate, and L acting only as a tetradentate chelate together with two bidentate acac ligands. Photophysical studies of the complexes were carried out. The Tb(III) and Eu(III) complexes show strong emissions both in solid state and solution. The intensity of the luminescence of Dy(III) and Sm(III) are relatively weak. The factors determining the intensity of the photoluminescence are discussed.

Anionic lanthanide complexes with 3-methyl-1-phenyl-4-formylpyrazole-5-one and hydroxonium as counter ion.

A series of [H3O]+[LnL4]-·nH2O complexes (n = 1-3, Ln = Nd, (1), Sm (2), Eu (3), Tb (4); HL = 3-methyl-1-phenyl-4-formylpyrazole-5-one) were synthesized and characterized. The structures of the SmIII and EuIII complexes were investigated by X-ray diffraction. The isostructutal crystalls 2 and 3 consist the tetrakis [LnL4]- anions which are linked by H-bonding with the hydroxonium counter-ion and water molecules. The lanthanide ion is situated in the center of distorted tetragonal antiprism formed by eight oxygen atoms of 4-formyl-5-hydroxypyrazolonate anions. The TbIII and SmIII complexes show strong luminescence in solid state, whereas the EuIII and NdIII complexes show low luminescence activity.

Ln(III) complexes of a bis(5-(pyridine-2-yl)-1,2,4-triazol-3-yl)methane ligand: synthesis, structure and fluorescent properties.

The new tetradentate ligand H2L bis(5-(pyridine-2-yl)-1,2,4-triazol-3-yl)methane ligand H2L has been used to prepare corresponding Ln(III) complexes [Ln(L)(HL)H2O]·6H2O where Ln(III) is Tb(III), Sm(III), Eu(III), Gd(III), Nd(III). The resulting complexes were investigated by various means including elemental- and thermogravimetric analysis and IR-, UV-, VIS spectroscopy. The complexes form an isostructural series in the solid state according to X-ray diffraction. The optimal value of triple state energy of the ligand sensitizes both fluorescent visible and near-IR emissions of the lanthanides. However, the overall emission is moderate as a result of the quenching action of coordinated water molecules. The displacement of water molecules from the inner coordination sphere both in solid samples and the solutions results in a significant increase of the efficiency of the luminescence. The best value of the quantum yield was obtained for the Tb(III) complex with 41%. Luminescence titrations demonstrate that [Tb(L)(HL)H2O] is a pH-sensitive emitter which is able to detect pH values in both near neutral pH and acidic pH ranges.

Photo- and electroluminescent properties europium complexes using bistriazole ligands.

Luminescent properties of two heteroleptic dibenzoylmethanate europium(III) complexes with 1,3-bis(5-pyridin-2-yl-1,2,4-triazol-3-yl)propane (H2L1) and 1,4-bis(5-pyridin-2-yl-1,2,4-triazol-3-yl)butane (H2L2) as ancillary ligands are described. The two double-layer-type electroluminescent cells with the structures: (1) ITO/NPB(40 nm)/Eu(DBM)2HL1 (40 nm)/LiF (1 nm)/Al (100 nm) and (2) ITO/NPB(40 nm)/Eu(DBM)2HL2 (40 nm)/LiF (1 nm)/Al (100 nm) emit red light originating from the europium complexes. The device 2 gives the maximum brightness of 455 cd/m2 at 19.2 V.

Structural and photophysical studies on ternary Sm(III), Nd(III), Yb(III), Er(III) complexes containing pyridyltriazole ligands.

Two bidentate pyridine-triazole ligands (3-(pyridine-2-yl)-5-phenyl-1,2,4-triazole (L1) and 5-phenyl-2-(2'-pyridyl)-7,8-benzo-6,5-dihydro-1,3,6-triazaindolizine (L2)), have been synthesized and used for Ln(Dbm)3 (Ln = Sm(III), Nd(III), Yb(III) and Er(III)) coordination. The structures of the ligands and resulting Sm(III) complex were determined in the solid state by X-ray diffraction. The title complexes were characterized by UV, fluorescent, IR-spectroscopy and thermogravimetric and elemental analyses. Photophysical studies on the Ln(III) complexes were carried out showing luminescence in the region typical for Ln(III). The effect of various factors on the enhancement luminescence of complexes is discussed.