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.

Mononuclear copper(I) complexes bearing a 3-phenyl-5-(pyridin-4-yl)-1,2,4-triazole ligand: synthesis, crystal structure, TADF-luminescence, and mechanochromic effects.

Three new mononuclear heteroleptic copper(I) halide complexes, [CuL(PPh3)2X] (X = Cl, Br, I), based on 3-phenyl-5-(pyridin-4-yl)-1,2,4-triazole (L) and triphenylphosphine (PPh3) ligands, have been prepared by reaction of CuX (X = Cl, Br, I), L and PPh3 in a molar ratio of 1 : 1 : 2 in MeCN solutions. The synthesized complexes exhibit blue light emission in solutions and bright green emission in the crystal state with quantum yields of up to 100%. The luminescence decay analysis and density functional theory calculations revealed that the emission of solid samples at room temperature corresponds to the thermally activated delayed fluorescence, while that at 77 K is assigned to phosphorescence. Utilizing the studied complexes in OLED heterostructures resulted in high-performing green-emitting devices with an external quantum efficiency of up to 13.4%.

Structure and emission properties of dinuclear copper(i) complexes with pyridyltriazole.

A new series of five highly emissive binuclear heteroleptic pyridyltriazole-Cu(i)-phosphine complexes 1-5 was synthesized and examined by different experimental (IR, elemental and thermogravimetric analysis, single crystal X-ray diffraction technique, UV-vis and fluorescence spectroscopy) and quantum chemical aproaches. Complexes 1-5 exhibited excellent stimuli-responsive photoluminescent performance in the solid state at room temperature (quantum yield (QY) = 27.5-52.0%; lifetime (τ) = 8.3-10.7 µs) and when the temperature was lowered to 77 K (QY = 38.3-88.2; τ = 17.8-134.7 µs). The highest QY was examined for complex 3 (52%) that can be explained by the small structural changes between the ground S0 and exited S1 and T1 states leading to the small S1-T1 triplet gap and efficient thermally-activated delayed fluorescence. Moreover, complex 4 demonstrates reversible mechanochromic and excitation dependent luminescence.

Synthesis, Photoluminescence and Electrical Study of Pyrazolone-Based Azomethine Ligand Zn(II) Complexes.

New luminescent zinc complexes were obtained by reaction of pyrazolone-based azomethine ligands with Zn(CH3COO)2·2H2O. Complexes fully characterized by elemental analysis, FTIR, ES-MS, NMR, and single crystal X-ray analysis. Title complexes in the solid state demonstrate tunable luminescence from blue to orange by varying of substituents on the aromatic ring. Quantum yields are in the 0.03 to 0.49 range. TGA data shows that obtained complexes demonstrate high thermal stability and can be used as electroluminescent materials. The electrical properties of the complexes under study were considered in the ITO-Zncomplex-Al "sandwich" structure.

Structure and excitation-dependent emission of novel zinc complexes with pyridyltriazoles.

A series of Zn(ii) complexes with 5-(4-R-phenyl)-3-(pyridin-2-yl)-1,2,4-triazoles have been synthesized and subsequently characterized by single crystal X-ray diffraction, 1H-NMR, FT-IR spectroscopy, elemental analyses, ESI-MS, and PXRD. The X-ray diffraction analyses revealed that the complexes have a similar molecular structure and their supramolecular frameworks are constructed by hydrogen bonds and π⋯π interaction scaffolds. Upon irradiation with UV light, the studied complexes display deep blue emission at 396-436 nm in the solid state. The compounds show an unexpected excitation-dependent emission phenomenon which is detected by a change in the emission color (from blue to yellow) upon increase of the excitation wavelength. The conducted quantum-chemical calculations indicate that supramolecular differences in the single-crystal architecture of the synthesized complexes play a crucial role for this photophysical behaviour.

Luminescent Properties of Zn and Mg Complexes on N-(2-Carboxyphenyl)salicylidenimine Basis.

New zinc and magnesium complexes of N-(2-carboxyphenyl)salicylidenimine) were synthesized and structurally characterized by elemental analysis, FT-IR, and X-ray single-crystal analysis. These complexes exhibit tuneable luminescence in the solid state from blue to green by varying by metal ion and composition. Moreover, the quantum yields range from 0.11 to 0.41, while lifetimes were determined to be in the nanosecond timescale. Thermal analysis shows that these complexes exhibit good thermal stability and can therefore well be used as electroluminescent materials.