Copper Halide Complexes Research Articles

Synthesis and characterization of Bis(imino)phosphine [NPN] ligands and their copper(I) halide complexes

A series of four new bis(imino)phosphine [NPN] ligands PhP(C6H4-2-HC = NAr)2 (Ar = 4-OMeC6H4 (L1, 1), 4-ClC6H4 (L2, 2), 4-BrC6H4 (L3, 3), 2,6-iPr2C6H3 (L4, 4)) were synthesized and structurally characterized. Their reactions with Cu(I) halides CuX (X = Cl, Br, I) were explored for the assembly of coordination complexes LnCuX, and the effects of substituent (Ar) and anion (X) were also investigated in a comparative manner. It was found that the reaction of methoxy substituted L1 (Ar = 4-OMeC6H) with CuX gave the mononuclear Cu(I) complexes L1CuX (X = Cl (1a), Br (1b), I (1c)) with isostructural feature. In contrast, when halogen-substituted ligands L2-3 (4-ClC6H4, 4-BrC6H4) were applied, their reactions with CuCl afforded the formation of tetranuclear dimer [Ln(CuCl)2]2 (n = 2 (2a), 3 (3a)) bridged by the Cu2Cl2 square, regardless of the composition of the reactants. On the other hand, reactions of L2-3 with CuBr and CuI generated the mononuclear Cu(I) complexes LnCuX (n = 2, X = Br (2b), I (2c); n = 3, X = Br (3b), I (3c)) again. In all these cases above, L1-3 ligands played the tridentate role by biting the copper(I) centers through NPN sites. When the bulky L4 (Ar = 2,6-iPr2C6H3) was involved, the binuclear dimer (L4CuI)2 (4c) bridged by iodide anions was obtained, where each L4 ligand coordinated the copper center using the bidentate P^N mode with another imino arm pendant. In further exploration, 1,10-o-phenanthroline (denoted as phen) was introduced to produce the heteroleptic complex L1CuCl(phen) (1d), where both imino arms in L4 were pendent. The obtained ligand (L1-4) and Cu(I) complexes were characterized by melting point, elemental analysis, FT-IR, UV–Vis, NMR, and single crystal X-ray diffraction.

Synthesis and Structure of Copper(I) Halide Complexes with Halogen-Functionalized Isocyanide Ligands

Eleven copper(I) halide complexes [CuX(CNR)3] (X = Cl, Br; R = C6H3-2,6-Cl2, C6H3-2-Cl-6-Me, C6H3-2,6-Br2, C6H3-2-Br-6-Me; X = I, R = C6H3-2,6-Cl2, C6H3-2-Cl-6-Me, C6H3-2-Br-6-Me) bearing halogen-functionalized aromatic isocyanide ligands were synthesized. The compounds were characterized by atomic emission spectroscopy (Cu), IR, 1H NMR spectroscopy and high-resolution mass spectrometry. The structure of nine compounds was determined by X-ray diffraction. Structural studies allow to reveal that the supramolecular structure of the complexes is based on weak C–H···X (X = Cl, Br, I) interactions and π-stacking of the aromatic rings of isocyanide ligands.

Synthesis of Phosphorus/Arsenic Tridentate Ligands and Their Application for Luminescent Copper (I) Halide Complexes

AbstractWe synthesized arsenic analogs of a tridentate PPP ligand, bis[2‐(diphenylphosphino) phenyl] phenylphosphine, achieving yields of 40 % to 71 %. Additionally, we prepared copper (I) halide (CuX, X=Br, I) complexes with these ligands, with yields between 43 % and 84 %. Using both experimental and computational methods, we examined their structures and photophysical characteristics. Single crystal X‐ray diffraction showed that all eight complexes had distorted tetrahedral geometries. These complexes exhibited photoluminescence with emission bands peaking from 506 nm to 551 nm and quantum yields up to 0.92 at room temperature. Emission lifetimes varied and showed no direct correlation with quantum yields or wavelengths. Physical manipulation and solvent variations significantly altered their photoluminescent properties. DFT and TD‐DFT calculations revealed that higher arsenic content increased spin‐orbit coupling constants, with iodide complexes performing better than bromide ones due to heavier elements enhancing spin‐orbit coupling. Substituting phosphorus with arsenic significantly affected the luminescence quantum yield and lifetime, demonstrating the heavy‐atom effect of arsenic. The position of arsenic in the ligands critically influenced the photophysical outcomes of the CuX complexes.

Zinc(II) and copper(II) halide complexes of 2-(aminomethyl)aniline

The syntheses and structures of 2-(aminomethyl)aniline (2-AMAn) complexes of CuX2 and ZnX2 (X = Cl, Br) are reported: [(2-AMAn)ZnCl2] (1), [(2-AMAn)ZnBr2] (2), [(2-AMAn)2ZnCl2] (3), [(2-AMAn)2ZnBr2] (4), [(2-AMAn)2CuCl]Cl (5) and [(2-AMAn)2Cu(H2O)2]Br2 (6). Compounds 1 and 2 are isomorphous and crystallize in the monoclinic space group Ia with two coordinated halide ions and one chelating 2-AMAn ligand. Compounds 3 and 4 are also isomorphous and crystallize in the monoclinic space group P21/n with two monodentate 2-AMAn ligands and two coordinated halide ions. All four Zn(II) complexes are slightly distorted tetrahedral in geometry. The Cu(II) complexes are structurally distinct from the Zn(II) complexes. 5 crystallizes in the monoclinic space group P21/n and is strongly distorted square pyramidal in geometry with two chelating 2-AMAn ligands, one coordinated chloride ion and one dissociated chloride ion. The bromide compound, 6, crystallizes in the monoclinic space group P21/c, also with two chelating 2-AMAn ligands, but with two coordinated water molecules and both bromide ions dissociated in the lattice.

Syntheses, structures, photophysical properties and electroluminescent applications of dinuclear Copper(I) halide complexes containing 9-carbazolyl-substituted 1,2-Bis(diphenylphosphino)benzene

The studies on the photophysical properties of the copper(I) halide complexes based on rigid diphosphine ligands have attracted increasing attention. Here, six copper(I) halide complexes containing 9-carbazolyl-substituted 1,2-bis(diphenylphosphino)benzene, Cu2X2 (L1)2 and Cu2X2 (L2)2 [L1 = 1,2-bis(9-carbazolyl)-4,5-bis(diphenylphosphino)benzene, X = I (1), Br (2), Cl (3); L2 = 1-(9-carbazolyl)-3,4-bis(diphenylphosphino)benzene, X = I (4), Br (5), Cl (6)], were synthesized and characterized. In these complexes, two copper(I) centers are bridged by two halogen ligands to form a dinuclear structure with a four membered Cu2X2 ring. They exhibited efficient yellow green to yellowish orange delayed fluorescence in the powder state at ambient temperature, with peak wavelengths located between 548 and 602 nm (τ = 1.2–2.3 μs; Φ = 0.09–0.53). The introduction of one or two 9-carbazolyl substituents into the diphosphine resulted in the red shifting emission, shorter decay time and higher thermal stability of the complexes. The emission of the complexes originates from (metal + halide)-to-ligand and intraligand charge transitions. Organic light-emitting devices based on complex 1 exhibit yellow green luminescence with maximum external quantum efficiency of 12.0 % and current efficiency of 32.64 cd A−1.

Columnar Liquid Crystals of Copper(I) Complexes with Ionic Conductivity and Solid State Emission.

Two neutral copper(I) halide complexes ([Cu(BTU)2X], X = Cl, Br) were prepared by the reduction of the corresponding copper(II) halides (chloride or bromide) with a benzoylthiourea (BTU, N-(3,4-diheptyloxybenzoyl)-N'-(4-heptadecafluorooctylphenyl)thiourea) ligand in ethanol. The two copper(I) complexes show a very interesting combination of 2D supramolecular structures, liquid crystalline, emission, and 1D ionic conduction properties. Their chemical structure was ascribed based on ESI-MS, elemental analysis, IR, and NMR spectroscopies (1H and 13C), while the mesomorphic behavior was analyzed through a combination of differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and powder X-ray diffraction (XRD). These new copper(I) complexes have mesomorphic properties and exhibit a hexagonal columnar mesophase over a large temperature range, more than 100 K, as evidenced by DSC studies and POM observations. The thermogravimetric analysis (TG) indicated a very good thermal stability of these samples up to the isotropization temperatures and over the whole temperature range of the liquid crystalline phase existence. Both complexes displayed a solid-state emission with quantum yields up to 8% at ambient temperature. The electrical properties of the new metallomesogens were investigated by variable temperature dielectric spectroscopy over the entire temperature range of the liquid crystalline phase. It was found that the liquid crystal phases favoured anhydrous proton conduction provided by the hydrogen-bonding networks formed by the NH…X moieties (X = halide or oxygen) of the benzoylthiourea ligand in the copper(I) complexes. A proton conductivity of 2.97 × 10-7 S·cm-1 was achieved at 430 K for the chloro-complex and 1.37 × 10-6 S·cm-1 at 440K for the related bromo-complex.

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%.

Thermally Activated Delayed Fluorescent Scintillators Based on Mononuclear Copper(I) Halide Complexes for High‐Resolution X‐Ray Imaging

AbstractScintillators have attracted tremendous attention due to their great potential in radiation detection, industrial non‐destructive testing, and medical theranostic applications. Thermally activated delayed fluorescence (TADF) based scintillators can simultaneously harvest radiation‐induced singlet and triplet excitons for high‐efficient X‐ray excited luminescence. However, pure organic TADF materials composed of light elements exhibit low X‐ray absorption coefficients, resulting in relatively weak X‐ray excited luminescence. Herein, a series of novel high‐performance X‐ray scintillators based on TADF mononuclear Cu(I)‐halide complexes are successfully developed. Together with high X‐ray absorption coefficient of heavy halogen elements and halide‐to‐ligand charge transfer characteristics, these TADF scintillators display excellent performance with high X‐ray relative light yields (as high as 28385 ± 1335 photons MeV−1), good linear response to X‐ray dose rate and high resistance to humidity and radiation. X‐ray imaging tests show that a relatively high spatial resolution of 9.8 lp/mm is realized based on their flexible scintillator films. These features suggest that it is a promising strategy to realize strong X‐ray excited luminescence by incorporating heavy halogen elements in TADF materials, providing more possibilities for exploring new low‐cost and high‐performance scintillators.

NHSi/NHGe-Supported Copper Halide and Pseudohalide Complexes: Synthesis and Application

NHSi/NHGe-Supported Copper Halide and Pseudohalide Complexes: Synthesis and Application

Coordination chemistry and magnetic properties of copper(II) halide complexes of quinoline

Complexes Cu(quin)2X2 [quin = quinoline, X = Cl (1), Br (2)] have been prepared and characterized via single-crystal X-ray diffraction and variable temperature magnetization measurements. The compounds are isomorphous in the monoclinic space group C2/c and crystallize as square planar complexes linked into chains via short X…X contacts. Magnetic susceptibility data were collected over the temperature range 1.8–300 K and were fitted to the one-dimensional Heisenberg antiferromagnetic model yielding J/kB = −33.7(5) K (1) and −145(4) K (2) with the larger exchange in the bromide complex a result of greater overlap due to the larger van der Waals contribution. Low temperature data indicate the presence of some short chains in the sample which provide for a paramagnetic contribution (odd length chains) or diamagnetic contribution (even length chains) at the lowest temperatures.

Mononuclear Tricoordinate Copper(I) and Silver(I) Halide Complexes of a Sterically Bulky Thiourea Ligand and a Computational Insight of Their Interaction with Human Insulin.

Reaction of two equivalents of the bulky 1,3-bis(2,6-diethylphenyl)thiourea ligand (L) with MX (being M = Cu+, Ag+; and X = Cl−, Br−, I−) in acetonitrile afforded neutral complexes of the type [MXL2] [CuClL2].2CH3CN (1a); [CuBrL2].2CH3CN (1b); [CuIL2] (1c): [AgClL2] (2a); [AgBrL2] (2b) and [AgIL2] (2c). The two aromatic groups in free ligand were found to be trans with respect to the thiourea unit, which was a reason to link the ligand molecules via intermolecular hydrogen bonding. Intramolecular hydrogen bonding was observed in all metal complexes. The copper complexes 1a and 1b are acetonitrile solvated and show not only intra- but also intermolecular hydrogen bonding between the coordinated thiourea and the solvated acetonitrile molecules. Silver complexes reported here are the first examples of structurally characterized tricoordinated thiourea-stabilized monomeric silver(I) halides. Molecular docking studies were carried out to analyze the binding modes of the metal complexes inside the active site of the human insulin (HI) protein. Analysis of the docked conformations revealed that the electrostatic and aromatic interactions of the protein N-terminal residues (i.e., Phe and His) may assist in anchoring and stabilizing the metal complexes inside the active site. According to the results of docking studies, the silver complexes exhibited the strongest inhibitory capability against the HI protein, which possesses a deactivating group, directly bonded to silver. All compounds were fully characterized by elemental analysis, NMR spectroscopy, and molecular structures of the ligand, and five out of six metal complexes were also confirmed by single-crystal X-ray diffraction.

Mononuclear Cu(I) halide complexes with two thiophenyl rings triphosphine: Structure and photophysical properties

Rigid aryl ring-based triphosphine can be used to construct highly emissive Cu(I) halide complexes applied in OLEDs, but rigid heteroaryl ring-based triphosphine Cu(I) halide complexes are rarely reported. Here, six mononuclear copper(I) halide complexes with two thiophenyl rings triphosphine CuX (L1) and CuX (L2) [L1 = (2,5-Me-3-PPh2-C4S)2PPh, X = I (1), Br (2) Cl (3); L2 = (3-PPh2-C4H2S)2PPh, X = I (4), Br (5) Cl (6)], were successfully synthesized and characterized on their structures and photophysical properties. The introduction of four methyl groups into two thiophenyl rings, improves the solubility and quantum yield, and fine-tunes the light-emitting color of complexes. At room temperature, complexes 1–6 in powder state exhibit intense green to yellow green delayed fluorescence (λem = 502–528 nm, τ = 16.1–63.0 μs, Φ = 0.21–0.35 for 1–3; λem = 507–559 nm, τ = 3.9–13.3 μs; Φ = 0.04–0.27 for 4–6). The emissions of the complexes 1–6 are originated from (metal + halide) to ligand and intra-ligand charge transitions. Solution-processed, complex 3-based nondoped and doped devices emit yellow and yellow green light with CIE of (0.48, 0.48) and (0.41, 0.51), respectively. The doped device achieves a maximum external quantum efficiency (EQE) of 3.12%, and a maximum luminance of 2280 cd/m2. The EQE value is the highest among reported mononuclear Cu(I) halide complexes with triphosphine based devices by solution-processed method.

Three-coordinated mononuclear Cu(I) complexes with crystallization-enhanced thermally activated delayed fluorescence characteristics

Triangular three-coordinated copper(I) halide complexes (1 (I), 2 (Br)) were developed based on a rigid bidentate P-donor ligand functionalized with electron-deficient pyridoimidazole moiety. The results of the temperature-dependent spectroscopic properties reveal that both Cu(I) complexes in crystalline powder at 298 K achieve orange thermally activated delayed fluorescence (TADF) with high photoluminescence quantum yields of 77% for 1 and 56% for 2, and microsecond lifetimes of 55.1 μs (1) and 73.5 μs (2), respectively. Additionally, aromatic CH···π interactions in molecular packing structures constitute an appealing class of crystallization-induced emission enhancement (CIEE) complexes. The results suggest that such highly efficient copper-based stimuli-responsive materials are beneficial for a broad range of applications.

Copper Iodide Clusters Coordinated by Emissive Cyanobiphenyl-Based Ligands.

Copper(I) halides are currently the subject of intensive research because of their rich photophysical properties combined with economic and eco-friendly advantages for practical applications. The molecular copper iodide cluster of the general formula [Cu4I4L4] (L = ligand) is a well-known photoluminescent compound, and the possibility to enlarge the panel of its photophysical properties is studied here, by exploring ligands bearing a distinct emitter. The comparative study of five copper iodide clusters coordinated by different phosphine ligands functionalized by the emissive cyanobiphenyl (CBP) group is thus described in this work. The emissive properties of the ligands have a great impact onto the photophysical properties of the cluster. Compared with classical [Cu4I4L4] copper iodide clusters, the origin of the emission bands is largely modified. The CBP moiety of electron acceptor character significantly lowers in energy the vacant orbitals and consequently affects the global energetic layout. These clusters present dual emission based on two different emissive centers which interplay through energy transfer. This study demonstrates that the design of original ligands is an effective approach to enrich the photophysical properties of the appealing family of copper halide complexes.

Sterically hindered mononuclear and binuclear Cu(I) complexes: Synthesis, characterization, docking analysis and antimicrobial evaluation

Mononuclear (1:3) and dinuclear (1:1.5 and 1:1), of the Copper(I) halide complexes containing triphenylphosphine, tri-metatolylphosphine, tri-(o-tolylphosphine) and tri-(p-tolylphosphine) were synthesized by the direct reactions of copper halide salts and phosphine ligands. Twelve complexes were synthesized, in which some complexes have been already reported and resynthesized by modifying the previous reported procedure. The structures and composition of the synthesized complexes were characterized by various techniques like Fourier Transform Infra-Red (FTIR), 1H, 13C, 31P NMR spectroscopy, single crystal XRD and EDX techniques. Most of the complexes exhibit mononuclear tetrahedral geometry while those with substituted phosphines exhibit bridged binuclear mode in which one copper atom exhibits distorted tetrahedral while the other copper exhibits trigonal geometry. The synthesized compounds are also evaluated for antibacterial and antifungal activity and theoretically studied for their affinity against different antibacterial targets as well as antifungal target. It was concluded that compound I showed enhanced binding affinity for both antibacterial and antifungal targets.

Recent Progress in Luminescent Cu(I) Halide Complexes: A Mini-Review.

Copper(I) halide complexes are well sought-after materials due to their rich structural diversities and photophysical properties. Profoundly, there is a direct relationship between each structural variation and luminescence of these complexes, for a purported use. In this review, recent publications within the last 2 years about copper(I) halide complexes, centering on their structural dimensionalities with derivatives of nitrogen, phosphorus, and sulfur ligands, have been considered alongside their effects on luminescence.

Quantum chemical study of structural properties for copper halide complexes with protonated acetamides

The chemistry of copper complexes, which contain organic ligands, is one of theimportant research areas for modern chemical technology and science. Herein, the coppercomplexes coordinated with organic ligands are playing an important role in many applicationsincluding crop production, animal husbandry, and pharmacology. At this point, the coordinationof copper halides with acetamides are good research object for fundamental research. The purposeof the article is to perform quantum chemical calculations, and analysis for the coordination ofcopper halides (chloride, bromide) with acetamides using HyperChem software and PM3 method.The study helps with the rational design of copper halide complexes with acetamides

Copper(I) halide complexes with n,n’-diallylthiomorpholinium chloride: synthesis and crystal structure

By means of alternating current electrochemical technique, basing on ethanolic solutions of CuCl 2 ·2H 2 O or CuBr 2 and N,N’-diallylthiomorpholinium chloride, the two isostructural s-complexes of [C 4 H 8 NS(C 3 H 5 ) 2 Cu Hal 2 ] composition were obtained in a single crystal form and characterized by X-ray single crystal method: sp. gr. P 2 1 / c , Z = 4, Hal = Cl ( І ) – a = 7.7763(4), b = 13.1892(5), c = 13.1761(6) Å, β = 103.470(5)°, V = 1314.2(1) Å 3 , r calc. = 1.611 g/сm 3 , m (MoK a ) = 2.20 mm −1 , q max. = 28.8°, 10141 measured, 2659 used reflections, R ( F 2 ) = 0.032, S = 1.07; Hal = 1,04Br/0,96Cl ( ІІ ) – a = 7.9771(3), b = 13.2391(5), c = 13.1422(5) Å, β = 103.942(4), V = 1347.1(1) Å 3 , r calc. = 1.80 g/см 3 , m (MoK a ) = 5.02 mm −1 , q max. = 29.0°, 21269 measured, 2772 used reflections, R ( F 2 ) = 0.027, S = 1.08. In the crystal structure of the studied compounds, the trigonal-pyramidal coordination environment of Cu(I) includes sulfur atoms of the organic cation and three chloride anions (compound I ) or chloride/bromide mixture (compound II ). Atoms occupying position Hal (2) perform a bridging function and connect individual coordination polyhedrons into dimeric topological units {L 2 Cu 2 Hal 4 }. These dimers through hydrogen bonding are linked into a three-dimensional framework. None of the available allylic groups of the N,N’-diallylthiomorpholinium cation are coordinated to the copper(I) ion. In our opinion, this feature of the discussed crystal structure of [(C 4 H 8 NS(C 3 H 5 ) 2 )Cu Hal 2 ] compounds is explained by the influence of competition between the sulfur atom and the C=C bond of the allyl group of the cation during complexation in solution and the redistribution of electron density in the crystal structure of solid compounds due to hydrogen contacts C–H… Hal . Keywords : N,N’-diallylthiomorpholinium; copper(І); s-complexes; crystal structure.

Complexes of Copper(II) Halides with 2-(3,5-Dimethylpyrazol-1-yl)benzimidazole: Synthesis and Magnetic and Cytotoxic Properties

Complexes of Copper(II) Halides with 2-(3,5-Dimethylpyrazol-1-yl)benzimidazole: Synthesis and Magnetic and Cytotoxic Properties

Copper (II) halide complexes with NNO tridentate ligand as chromotropic probes; synthesis, structural characterization and spectroscopic properties

• Two new copper (II) complexes with halide and NNO ligands were synthesized. • The complexes exhibit solvatochromism, thermochromism, and halochromism. • Copper-halogen bands of the complexes dissociate by increasing solvent polarity. • Reversible structural changes in solution is responsible for observed chromotropism. This study reports chromotropism of two newly synthesized copper(II) complexes of formula [CuLCl 2 ] and [CuLBr 2 ]•MeOH where L = N -(2-pyridylmethyl)-1-hydroxypropylamine. The structure of the complexes was investigated by infrared spectroscopy, electronic absorption spectroscopy, elemental analysis, molar conductance measurements, and thermal analysis. Single Crystal X-ray structure determination reveals both complexes to adopt a distorted square-pyramidal geometry. Their chromotropic properties were investigated using electronic absorption spectroscopy. The complexes are solvatochromic in solvents with different polarities. The aqueous solutions of the complexes exhibit a variety of colors in the pH range of 1.8 to 11.4 showing that the compounds are halochromic. The complexes are also thermochromic and show reversible color changes in different temperatures in dimethyl sulfoxide solutions. The solution study reveals that the observed chromotropism originates from structural changes of the complexes in different conditions.