Copper Halide Complexes Research Articles

Synthesis and study of complexes of cobalt(II), nickel(II), and copper(II) halides with 2-(3,5-dimethylpyrazol-1-yl)benzimidazole

Synthesis and study of complexes of cobalt(II), nickel(II), and copper(II) halides with 2-(3,5-dimethylpyrazol-1-yl)benzimidazole

Synthetic Access to Ring-Expanded N-Heterocyclic Carbene (RE-NHC) Copper Complexes and Their Performance in Click Chemistry

The facile syntheses of ring-expanded N-heterocyclic carbene (RE-NHC) copper(I) halide complexes are reported. The method makes use of a weak inorganic base in a green solvent. The reaction times can be greatly reduced by use of this weak-base route under microwave irradiation. The easy access to these complexes permits an evaluation of the catalytic activity and reaction profiling of [Cu(RE-NHC)X] complexes in the Huisgen 1,3-cycloaddition reaction.

Largely Color-Tuning Prompt and Delayed Fluorescence: Dinuclear Cu(I) Halide Complexes with tert-Amines and Phosphines

Luminescent copper(I) halide complexes with bi- and tridentate rigid ligands have gained wide research interests. In this paper, six tetracoordinate dinuclear copper(I) halide complexes, Cu2X2(ppda)2 [ppda = 2-[2-(dimethylamino)phenyl(phenyl)phosphino]-N,N-dimethylaniline, X = I (1), Br (2), Cl (3)] and Cu2X2(pfda)2 [pfda = 2-[2-(dimethylamino)-4-(trifluoromethyl)phenyl(phenyl)phosphino]-N,N-dimethyl-5-trifluoromethylaniline, X = I (4), Br (5), Cl (6)], were successfully prepared and systematically characterized on their structures and photophysical properties. Complexes 1-5 have a centrosymmetric form with a planar Cu2X2 unit, and complex 6 has a mirror symmetry form with a butterfly-shaped Cu2X2. Solid complexes 1, 4, and 5 emit delayed fluorescence at room temperature, intense blue to greenish yellow (λmax = 443-570 nm) light, and their peak wavelengths are located at 443-570 nm with microsecond lifetimes (τ = 0.4-19.2 μs, ΦPL = 0.05-0.48). Complexes 2, 3, and 6 show prompt fluorescence, very weak yellowish green to yellow (λmax = 534-595 nm) emission with peak wavelengths at 534-595 nm, and lifetimes in nanoseconds (τ = 4.4-9.3 ns, ΦPL < 0.0001). (Metal + halide) to ligand and intraligand charge transitions are the main origin of the emission of the complexes. Solution-processed, complex-4-based nondoped and doped devices emit yellow green light with CIE coordinated at (0.41, 0.51), a maximum EQE up to 0.17%, and luminance reaching 75.52 cd/m2.

Synthesis, crystal structure and DFT study of a dinuclear CuI complex with (E)-2-benzylidene- N-methylhydrazinecarbothioamide: Role of halogen-hydrogen bonds in copper-copper bridge bonding

An equimolar reaction of copper(I) chloride with the (E)-2-benzylidene-N-methylhydrazinecarbothioamide (btscH-N1HMe) thio-ligand in acetonitrile followed by the addition of one equivalent of triphenylphosphine (Ph3P) gave crystals. The elemental analysis, and infrared and proton NMR spectra of the crystals supported the empirical composition, {CuCl(Ph3P)(btscH-N1HMe)}, and single crystal X-ray crystallography revealed formation of the dinuclear compound, [Cu2(µ-Cl)2(Ph3P)2(κ1S-btscH-N1HMe)2] (1). There is intramolecular H-bonding between the hydrazinic hydrogen atom (N2-H) and chloride ion {NH⋅⋅⋅Cl, 2.29; N⋅⋅⋅Cl, 3.144 Å}. The intermolecular H-bonding between the dimeric units led to the formation of a H-bonded 1 D polymer. DFT calculations on complexes of copper(I) halides with the model thiosemicarbazone, {H2C2=N3-N(H)-C(=S)-N1HMe}, and PH3 as a co-ligand, revealed the formation of halogen-bridged or sulfur-bridged dinuclear complexes, without or with the halogen - solvent/water hydrogen bonding. Some interesting conclusions are inferred from the experimental-theoretical correlations.

Phenyldiquinolinylarsine as a Nitrogen‐Arsenic‐Nitrogen Pincer Ligand

A nitrogen‐arsenic‐nitrogen (NAN) ligand, phenyldiquinolinylarsine (pdqa), was newly synthesized by utilizing diiodophenylarsine as a key precursor. The copper(I) halide (CuX, X = Cl, Br, I) and gold(I) chloride (AuCl) complexes of pdqa were synthesized and their structures were analyzed by NMR spectroscopy and X‐ray crystallography. [CuX(pdqa)] formed pincer complexes, while only the arsenic atom coordinated to the AuI ion in [AuCl(pdqa)]. Moreover, it was found that steric strain for forming the pincer coordination was relieved around the arsenic atom, which had less directional coordination, when comparing the structure of a CuI complex with bidentate ligand diphenylquinolinylarsine.

Dinuclear Cu(I) Halides with Terphenyl Phosphines: Synthesis, Photophysical Studies, and Catalytic Applications in CuAAC Reactions.

Several dinuclear terphenyl phosphine copper(I) halide complexes of composition [CuX(PR2Ar')]2 (X = Cl, Br, I; R = hydrocarbyl, Ar' = 2,6-diarylterphenyl radical), 1-5, have been isolated from the reaction of CuX with 1 equiv of the phosphine ligand. Most of them have been characterized by X-ray diffraction studies in the solid state, thus allowing comparative discussions of different structural parameters, namely, Cu···Cu and Cu···Aryl separations, conformations adopted by coordinated phosphines, and planarity of the Cu2X2 cores. Centrosymmetric complexes [CuI(PMe2ArXyl2)]2, 1c, and [CuI(PEt2ArMes2)]2, 3c, despite their similar structures, show very distinct photoluminescence (PL) in powder form at room temperature. The photophysical behavior of these compounds in liquid solution, solid-solid Zeonex solution and powder samples at room temperature and 77 K have been investigated and supported by DFT calculation. Identification of vibronic coupling modes, done by group theory calculations and the technique of projection operators, shows that the manifestation of these modes is conditioned by crystal packing. Complexes [CuI(PMe2ArXyl2)]2, 1c, and [CuI(PEt2ArMes2)]2, 3c, display remarkable activity in copper-catalyzed azide-alkyne cycloaddition reactions involving preformed and in situ-made azides. Reactions are performed in H2O, under aerobic conditions, with low catalyst loadings and tolerate the use of iodoalkynes as substrates.

Synthesis and Characterization of Copper(I) Halide Complexes Prepared with Bipodal Diacylthioureas

Bipodal diacylthioureas [MesC(O)NHC(S)NH]2R (R = C6H4‐1,2 (L1, 1), C6H4‐1,4 (L2, 2)) were synthesized, and their complexation reactions with equimolar Cu(I) halides CuX (X = Cl, Br, ) were investigated. The obtained ligands L1–2 and the resultant Cu(I) complexes (3–8) were characterized by FT‐IR, 1H NMR, 13C NMR spectroscopy, elemental analysis and single‐crystal X‐ray diffraction. The complexation of L1 with CuX gave three different 1D polymers: the infinite single chain (L1CuCl)n (3), edge‐shared double‐ring chain {[(µ‐L1)CuBr]2}n (4), and vertex‐shared double‐ring chain {[L1Cu(µ‐I)]2}n (5). Similarly, but more pronounced, the treatment of L2 with CuX resulted in the formation of 1D edge‐shared double‐ring chain {[(µ‐L2)CuCl]2}n (6), 0D discrete dinuclear metallamacrocyclic ring (L2CuBr)2 (7), and 3D network polymer [L2Cu(µ‐I)]n (8), respectively. The structural diversity may be related to the suitable spacer, flexible C=S directionality and binding roles of halide anions and sulfur donors. Among Cu(I) complexes (3–8) as prepared, both chloride (in 3 and 6) and bromide anions (in 4 and 7) acted as terminal ligands, while the iodide anions (in 5 and 8) served as bridging ligand. In contrast, only in edge‐shared double‐ring chains (4 and 6) it was found that the sulfur donors (one of two in each Ln) played as the bridging ligand.

C(sp3)-H Fluorination with a Copper(II)/(III) Redox Couple.

Despite the growing interest in the synthesis of fluorinated organic compounds, few reactions are able to incorporate fluoride ions directly into alkyl C-H bonds. Here, we report the C(sp3)-H fluorination reactivity of a formally copper(III) fluoride complex. The C-H fluorination intermediate, LCuF, along with its chloride and bromide analogues, LCuCl and LCuBr, were prepared directly from halide sources with a chemical oxidant and fully characterized with single-crystal X-ray diffraction, X-ray absorption spectroscopy, UV-vis spectroscopy, and 1H nuclear magnetic resonance spectroscopy. Quantum chemical calculations reveal significant halide radical character for all complexes, suggesting their ability to initiate and terminate a C(sp3)-H halogenation sequence by sequential hydrogen atom abstraction (HAA) and radical capture. The capability of HAA by the formally copper(III) halide complexes was explored with 9,10-dihydroanthracene, revealing that LCuF exhibits rates 2 orders of magnitude higher than LCuCl and LCuBr. In contrast, all three complexes efficiently capture carbon radicals to afford C(sp3)-halogen bonds. Mechanistic investigation of radical capture with a triphenylmethyl radical revealed that LCuF proceeds through a concerted mechanism, while LCuCl and LCuBr follow a stepwise electron transfer-halide transfer pathway. The capability of LCuF to perform both hydrogen atom abstraction and radical capture was leveraged to enable fluorination of allylic and benzylic C-H bonds and α-C-H bonds of ethers at room temperature.

Synthesis, Crystal Structure and DFT Study of a Dinuclear Cu &lt;sup&gt;1&lt;/sup&gt; Complex With (E)-2-Benzylidene-N-Methylhydrazinecarbothioamide: Role of Halogen-Hydrogen Bonds in Copper-Copper Bridge Bonding

An equimolar reaction of copper(I) chloride with the (E)-2-benzylidene-N-methylhydrazine -carbothioamide (btscH-N 1 HMe) thio-ligand in acetonitrile followed by the addition of one mole of triphenyl phosphine(Ph 3 P) gave crystals of empirical composition, {CuCl(Ph 3 P)(btscH-N 1 HMe)}. The infrared spectroscopy, 1 H-NMR spectroscopy and single crystal x-ray crystallography revealed the formation of the di-nuclear compound, [Cu 2 (m-Cl) 2 (Ph 3 P) 2 (k 1 S-btscH-N 1 HMe) 2 ] 1 . Crystal Data : M, C 54 H 52 Cl 2 Cu 2 N 6 P 2 S 2 ; crystal system, triclinic; space group, Pī; a, 10.98950(10); b, 11.03070(10); c, 12.0049(2) A; a,104.4680(10); b, 92.4550(10); g, 113.6630(10).° Intermolecular H-bonding between dimeric units led to the formation of a H-bonded polymer. DFT calculations on complexes of copper(I) halides with model thiosemicarbazone {H 2 C 2 =N 3 -N(H)-C(=S)-N 1 HMe} and PH 3 as a co-ligand revealed the formation of halogen-bridged or sulfur-bridged dinuclear complexes without or with halogen - solvent / water hydrogen bonding. Some interesting conclusions are inferred based on experimental-theoretical correlations.

Synthesis and crystal structure of copper(I) halide complexes with 1-allyl-4-cyanopyridinium cation

Synthesis and crystal structure of copper(I) halide complexes with 1-allyl-4-cyanopyridinium cation

Efficient TADF-OLEDs with ultra-soluble Copper(I) halide complexes containing non-symmetrically substituted bidentate phosphine and PPh3 ligands

High efficiency copper(I) halide complexes containing rigid diphosphine ligand have attracted much attention. However, rigid bidentate phosphine ligands were rarely reported so far and limited to structural symmetric diphosphines. Here, a series of four-coordinate mononuclear copper(I) halide complexes containing non-symmetrically substituted bidentate phosphine and PPh3 Ligands, CuX(dpts)(PPh3) [dpts = 2-trimethylsilyl-3,4-bis(diphenylphosphine)thiophene, X = I (1), Br (2), Cl (3)] and in comparison to CuX(dppt)(PPh3) [dppt = 3,4-bis(diphenylphosphino)thiophene, X = I (4), Br (5), Cl (6)], were synthesized, and their molecular structures and photophysical properties were investigated. The introduction of trimethylsilyl group into diphosphine ligand, not only greatly improves the solubility of the complexes, but also quantum efficiency, and fine-tunes the emission color as well. These complexes exhibit intense bluegreen to yellowish green emissions in powder state at room temperature and have peak wavelengths at 485–535 nm with microsecond lifetimes (τ = 4.8–48.9 μs, Φ = 0.03–0.52). The emission of the complexes 1–6 mainly originates from MLCT (metal to ligand charge transfer), XLCT (halide to ligand charge transfer) and intraligand transitions. Solution-processed, nondoped and doped devices of complex 2 exhibit yellow green emission with CIE(x,y) of (0.43, 0.51). The nondoped device gives a maximum external quantum efficiency (EQE) of 7.74% and a maximum luminance of 234 cd/m2. These promising results open the door to solution-processed, efficient TADF (thermally activated delayed fluorescence) OLED (organic light-emitting diode) devices with ultra-soluble and abundant copper emitters.

Complexes of Cobalt and Copper Halides Based on 1,3-Dimethylimidazolium-4-Carboxylate

In the interaction of norzooanemonin 1,3-dimethylimidazolium-4-carboxylate (1) with CuBr2, two types of crystals form: purple [Cu(L)2Br2][CuBr4][CuL4] (2) and light blue [CuL4][CuBr3] (3). In the reaction of 1 with CoCl2 in methanol, neutral complex Co(L)2Cl2 (4) forms. The thermal decomposition of complex 4 is studied. At the first stage of this decomposition, two equivalents of CO2 remove in a range 218–275 °C, and then a two-phase removal of two equivalents of L and the formation of CoCl2 occur.

Halide bridged novel ternary copper(I) complexes with bis imino-quinolinyl ligand and triphenylphosphine: Synthesis, structure, luminescence, electrochemistry and theoretical studies

Three new mixed ligand copper(I) halide complexes [Cu2(µL)(µ-I)2(PPh3)2]∞(1), [Cu2(µ-L) (µ-Br)2(PPh3)2]∞ (2) and [Cu2(µL)(µ-Cl)2)(PPh3)2]∞ (3) have been synthesized by exploiting reactions of equimolar proportion of CuX (X = I, Br and Cl), PPh3 and the imino-quinolinyl ligand L[N,N’-bis(4-quinoline)ideneethylenediamine]. These complexes have been characterized by elemental analyses, IR, UV–Vis and emission spectroscopy. The crystal structures of the complexes 1, 2 and 3 have been determined by single-crystal X-ray analysis and it has been found that all the complexes 1, 2 and 3 are 1-D co-ordination polymer having bridged ligand L and -{CuI-(µ-X2)-CuI}- rhomboid core (X = I, Br and Cl). At room temperature in dichloromethane the ligand L is non-emissive whereas the complexes 1, 2 and 3 are photo luminescent. The E1/2 values of the CuI-CuII couples of 1, 2 and 3 are 0.99, 1.02 and 0.96 V (vs. Ag/AgCl in 1 M KCl, scan rate 100 mV s−1) respectively. From TGA analysis it has been confirmed that these complexes are stable upto 260 °C. DFT and Hirshfeld surfaces computational studies have also been performed for these ternary complexes 1, 2 and 3.

DETERMINATION OF COMPOSITION AND CONSTRUCTION OF COMPLEX COMPOUNDS OF TRANSITION METALS WITH DERIVATIVES OF AMINES BY METHOD OF IR-SPECTROSCOPIES

Complex compounds of chloride and copper nitrate (II) with aliphatic amines R – NH 2 , R 2 – NH, R 3 – N, where R is C 2 H 5 ; C 3 H 5 ; C 4 H 9 ; CH 3 (CH 2 ) 9 ; C 5 H 11 ; and its substitutes from ethyl alcohol by merging solutions of copper (II) salts and amines in molecular ratios of 1:2, as well as complex compounds of copper (II) with N - derivatives of diethanolamine and benzyldiethylamine (RDEA), where R is C 3 H 5 ; C 3 H 7 ; C 4 H 7 or C 6 thH 5 CH 2 , diethanolamine – NH (C 2 H 4 OH) 2 , are synthesized. The absorption bands in the 440-420 cm -1 region, are identified which are related to ν (Cu – N) vibrations, that indicates about coordination through the nitrogen atom grounds. In the IR spectra of all complexes, an absorption band is observed in ligands in the region of 220-210 cm -1 , which disappears in the complex. In the complexes there are bands of absorption in the region 460-430 cm -1 , which are typical for copper (II) complexes with all amines and are practically independent of the amine radical. The absorption frequencies of copper (II) complexes with benzyl, alliamines can be explained by the dual nature of σ- and π-dative interactions. In the low-frequency region of complexes of copper (II) halides with pyridine and its substituted an increase in the oscillation frequencies in the region 270-240 cm -1 is observed. In the IR spectra of copper complexes with benzyldiethanolamines [Cu (BZDEA) 2 ] X 2 at interval 3500-3100 cm -1 two absorption bands appear. A band with a maximum at 3150 cm -1 probably refers to the absorption of coordinated OH groups. The coordination of the OH groups is confirmed by data in the absorption region v (C – 0), and also the appearance of the bands ν (Cu – O). The band of deformation vibrations of alcohol OH-groups at ~ 1650 cm -1 is shifted to the low-frequency region by 15 to 30 cm -1 . It can be determined only by the interaction of hydroxy groups with cis. Ligand is also coordinated through the nitrogen atom. This is confirmed by the pre-sence of absorption bands ν (Cu – N) in the region of 480-400 and 280-230 cm -1 . Therefore, the ligand is tridentate. Thus, according to the data of IR spectroscopy, molecules of N-derivatives diethanolamine form the bonds with c.y. through oxygen atoms of oxy groups. The fourth coordination site may be occupied by acid residues or the deprotonated oxygen atom of the hydroxy group performs a bridging function. Then the complex must have a dimeric or, in general, a polymeric structure.

Tin(II) 2-ethylhexanoate and ascorbic acid as reducing agents in solution ARGET ATRP: A kinetic study approach by mathematical modeling and simulation

The mechanism of activators regenerated by electron transfer (ARGET) associated with atom transfer radical polymerization (ATRP) has attracted attention because of the transition metal catalyst reduction in the conventional ATRP process. In this paper, a comprehensive mathematical model for solution ARGET ATRP technique is presented, following a distinct approach, in which reaction kinetics for the reducing agent is detailed. Tin(II) 2-ethylhexanoate and ascorbic acid were studied as reducing agents with copper(II) halide complex as a catalyst, and the ARGET mechanism for both of them was proposed and validated with experimental data available in the literature. The kinetic rate constants for such reducing agents (kr) were obtained by an optimization algorithm, and the molecular weights and dispersity were predicted using the method of moments. The higher the initial concentrations of copper (II) halide complex and reducing agent, the higher the number-average molecular weight and the lower the dispersity. Simulation results also confirm that the initial concentration of copper(II) halide complex is a critical parameter with higher sensitivity than the reducing agent in solution ARGET ATRP process.

Highly luminescent copper(i) halide complexes chelated with a tetradentate ligand (PNNP): synthesis, structure, photophysical properties and theoretical studies.

Two emissive copper(i) halide complexes (PNNP)Cu2Br2 (1) and (PNNP)Cu2I2 (2), which are constructed from butterfly-shaped dinuclear Cu2X2 cores and a new tetradentate ligand (PNNP = 1,3-bis(1-(2-(diphenylphosphanyl)phenyl)-1H-pyrazol-3-yl)benzene), were synthesized and characterized. These chelates exhibit bright green (λmax = 517 nm, 1) and bluish-green (λmax = 492 nm, 2) photoluminescence in the solid state with quantum yields of 42% (1) and 58% (2), and lifetimes of 13 μs (1) and 8.8 μs (2) at room temperature. Computational density functional theory/time-dependent density functional theory (DFT/TDDFT) calculations were performed to elucidate the nature of their electronic transitions and to predict their detailed photophysical properties. The results of DFT/TDDFT calculations, combined with the temperature dependence of spectroscopic properties and emission decay behaviors, suggest that the emission in the solid state originates from the 1,3(MLCT + XLCT + ILCT) excited states, which are in thermal equilibrium with small energy differences of about 0.1 eV. A comparative study of the titled complexes reveals that the emissive-state characteristics and photophysical properties of these complexes are significantly affected by the ligand field strength and atomic number of the halogen atom, as well as by the percentage of the XLCT transition involved in the lowest excited states. Compared with its bromide counterpart (1), the iodide complex (2) shows a much higher phosphorescence quantum yield (0.94 vs. 0.50), a much shorter phosphorescence decay time (58 μs vs. 274 μs), a much larger phosphorescence rate constant (1.6 × 104 s-1vs. 1.8 × 103 s-1), and a larger phosphorescence contribution (25% vs. 8%) in room-temperature emission, due to the more efficient spin-orbit coupling (SOC).

Syntheses and photoluminescence of copper(i) halide complexes containing dimethylthiophene bidentate phosphine ligands

Neutral dinuclear four-coordinate Cu(i) halide complexes containing thiophene exhibit intense bluish green to yellow green emission in the solid state at room temperature.

From deep blue to green emitting and ultralong fluorescent copper(i) halide complexes containing dimethylthiophene diphosphine and PPh3ligands

Highly emissive copper(i) halide complexes having thermally activated delayed fluorescence (TADF) have been paid much attention. Here, a series of four-coordinate mononuclear copper(i) halide complexes containing both bi- and mono-phosphine ligands, [CuX(dpmt)(PPh3)] (dpmt = 3,4-bis(diphenylphosphino)-2,5-dimethylthiophene, X = I (1), Br (2) and Cl (3)), were synthesized, and their molecular structures and photophysical properties were investigated. These complexes exhibit intense deep blue emission in crystal state at room temperature and have peak wavelengths at 447-460 nm with microsecond lifetimes (τ = 114-752 μs). Emission color can be largely tuned from deep blue to green, from crystal to film state at 293 K. The emission of the complexes 1-3 mainly originates from intraligand and LLCT transitions. Solution-processed, nondoped and doped devices of complex 3 exhibit yellowish green emission with CIE(x, y) of (0.3557, 0.5031). The nondoped device gives a maximum external quantum efficiency (EQE) of 2.47% and a maximum luminance of 316 cd m-2.

A new strategy to synthesize three-coordinate mononuclear copper(i) halide complexes containing a bulky terphenyl bidentate phosphine ligand and their luminescent properties

Three mononuclear three-coordinate Cu(i) halide complexes were synthesized by a new strategy and they exhibit green to yellow green emission in the solid state at room temperature.

Комплексы галогенидов кобальта и меди на основе 1,3-диметилимидазолий-4-карбоксилата

При взаимодействии норзооанемонина 1,3-диметилимидазолий-4-карбоксилата (1) с CuBr2 образуются два типа кристаллов: фиолетовые [Cu(L)2Br2][CuBr4][CuL4] (2) и голубые [CuL4][CuBr3] (3). В реакции 1 с CoCl2 в метаноле образуется нейтральный комплекс Co(L)2Cl2 (4). Для комплекса 4 был изучен термораспад, в ходе которого на первой стадии отщепляется два эквивалента CO2 в диапазоне 218—275 °C, после этого идет двухэтапное отщепление двух эквивалентов L и образование CoCl2.