Ca3Au6.61Ga4.39 – A New Gallide with a Three‐Dimensional Gold–Gallium Network

Ca₃Au_6.61Ga_4.39 was synthesized by reacting the elements in a glassy carbon crucible under argon in a water‐cooled sample chamber in a high‐frequency furnace. The compound crystallizes with a new hexagonal structure type, space group P6₃/mmc: Z = 2, a = 926.6(2), c = 733.1(2) pm, wR2 = 0.0832, 328 F values and 20 variables. This structure type consists of a remarkably complex three‐dimensional [Au_6.61Ga_4.39] network with significant Au–Au, Au–Ga, and Ga–Ga interactions. The calcium atoms are located within slightly distorted hexagonal channels of the gold–gallium network. The structural relations to the AlB₂ and Er₂RhSi₃ type structures are discussed.     

Synthesis,Single Crystal Growth and Crystal Structure of Ta7Cu10Ga34 – a 8 × 4 × 2 Super Structure of CsCl

Single crystals of Ta₇Cu₁₀Ga₃₄ were grown from the elements in a Cu/Ga melt. Ta₇Cu₁₀Ga₃₄ represents the first ternary compound of the system Ta/Cu/Ga. The crystal structure (Cmmm, oC102, Z = 2, a = 23.803(1), b = 12.2087(4), c = 5.7487(2) Å, 1291 refl. 78 parameters, R₁ = 0.037, wR₂ = 0.070). The crystal structure is characterized by rods of pentagonal prisms MGa₁₀, which are alternatingly occupied by Ta and Cu. Four of these rods are connected to columns running in direction (001). These columns are linked by cubic units TaGa₈, CuGa₈, and GaGa₈. According to the characteristic structural elements and the size of the unit cell Ta₇Cu₁₀Ga₃₄ represents a 8 × 4 × 2 super structure of CsCl or bcc. With respect to the underlying CsCl structure the formula can be written as [Ta₇Cu₁₀Ga₂□₁₃]Ga₃₂, i.e. a cubic primitive packing of 32 Ga atoms with Ta, Cu, and Ga in cubic voids and 13 vacancies. The pentagonal‐prismatic coordination of Ta and Cu can formally be obtained from the cubic primitive packing of Ga atoms by a 45° rotation of a part of the Ga₈ cubes. There is a close similarity to the binary compounds Ta₈Ga₄₁ and Ta_2–xGa_5+x. The first one is also related to a CsCl‐like structure, the latter one contains rods of pentagonal prisms, which form the same columns. There are also relations to the ternaries V₂Cu₃Ga₈ and V₁₁Cu₉Ga₄₆, whose cubic structures are more or less complex variants of CsCl.     

Hexamethyl-1,2,3-tristanna-[3]ferrocenophane – Molecular Structure and Cleavage of the Tin–Tin Bonds by Iodine,Sulfur, Selenium,and Tellurium

Hexamethyl-1,2,3-tristanna-[3]ferrocenophane ( 1 ) was prepared by the reaction of 1,1′-bis(dimethylstannyl)ferrocene ( 3 ) with bis(diethylamino)dimethylstannane. The molecular structure of 1 was determined by X-ray crystallography. The monoclinic unit cell (space group P2₁/c; a = 18.659(4), b = 17.311(3), c = 13.719(3) Å; β = 111.02(3)°) contains two independent molecules which differ slightly in their conformation. The cyclopentadienyl rings are almost parallel, but the positions of the substituted carbon atoms are twisted by τ £ 62° with respect to the ecliptic positions. The reactivity of 1 towards iodine and chalcogens E (E = S, Se, Te) was studied. Iodine reacts to give 1,1′-bis[iodo(dimethyl)stannyl]ferrocene ( 6 ) and dimethyltin diiodide. In the case of the chalcogens, the detectable and isolated products are 1,3-distanna-2-chalcogena-[3]ferrocenophanes (E = S ( 7 ), Se ( 8 ), Te ( 9 )) in addition to trimeric dimethyltin chalcogenides, (Me₂SnE)₃. Crystals suitable for X-ray structural analysis could be obtained of 1,3-distanna-2-thia-[3]ferrocenophane ( 7 ); the triclinic unit cell (space group P 1) has the dimensions a = 6.538(2), b = 9.013(2), c = 15.442(2) Å; α = 92.15(2), β = 91.89(2), γ = 109.43(2)°. The molecular structures of 1 and 7 are compared with those of other 1,3-distanna-[3]ferrocenophanes. All compounds were studied by NMR spectroscopy (¹H, ¹³C, ⁷⁷Se, ¹¹⁹Sn and ¹²⁵Te NMR) in order to establish the presence of the [3]ferrocenophanes 7 – 9 and of the cycles (Me₂SnE)₃ in solution.     

Gallium Zigzag Chains as an Ordering Principle in η5‐2,5‐di‐(t‐butyl) phospholylgallium(I)

The solid state structure of η⁵‐2,5‐di‐(t‐butyl)phospholylgallium(I) 1 was determined by X‐ray diffraction at 190 K. The molecules of 1 are partly organized in a for sandwich complexes new type of structure: a Ga zigzag chain in which the aromatic phospholyl rings alternate on both sides of the chain.     

Synthesis and reactivity of μ-η2-carbamato complexes of triosmium decacarbonyl

The synthesis of (-H)(-²-RRNCO₂)Os₃(CO)₁₀ (R=R=CH₃ 2a; R=R=CH₂CH₃,2b; R=CH₃, R=CH₂CH₃,2c) and their cyclic analogs (-H)(-²--CO₂)Os₃(CO)₁₀(n=42d,n=5,2e) from carbon dioxide, secondary amine, and Os₃(CO)₁₀(CH₃CN)₂ (1) are reported. A solid-state structure of2c reveals a bonding mode for the carbamato ligand very similar to that observed for related carboxylato complexes. Compound2c crystallizes in the orthorombic space group Pbca witha=9.136 (3),b=15.310 (4) andc=30.361 (5) Å;V=4247 ų,Z=8. Least-squares refinement of 2405 observed reflections gave a final agreement factor ofR=0.043 (R _w =0.043). The reactivity of the complexes2a–2e was examined. Compound2c or2b give good yields of the cluster derivatives (-H)(-X)Os₃(CO)₁₀ (X=Cl,3; X=OCH₃,4; X=N(CH₃)₂,7) when reacted with HX. Reaction of2a with P(CH₃)₃ at 68°C gives good yields of the otherwise difficult to obtain 1,1,2-(P(CH₃)₃)₃Os₃(CO)₉ (5). Evidence is presented that suggests that2a–2e form by oxidative addition of preformed carbamic acids to1.     

Synthesis,Characterization, Crystal Structure,and Biological Activities of Transition Metal Complexes with 1‐Phenyl‐3‐methyl‐5‐hydroxypyrazole‐4‐methylene‐8′‐quinolineimine

The Schiff base ligand, 1‐phenyl‐3‐methyl‐5‐hydroxypyrazole‐4‐methylene‐8′‐quinolineimine, and its Cu^II, Zn^II, and Ni^II complexes were synthesized and characterized. The crystal structure of the Zn^II complex was determined by single‐crystal X‐ray diffraction, indicating that the metal ions and Schiff base ligand can form mononuclear six‐coordination complexes with 1:1 metal‐to‐ligand stoichiometry at the metal ions as centers. The binding mechanism and affinity of the ligand and its metal complexes to calf thymus DNA (CT DNA) were investigated by UV/Vis spectroscopy, fluorescence titration spectroscopy, EB displacement experiments, and viscosity measurements, indicating that the free ligand and its metal complexes can bind to DNA via an intercalation mode with the binding constants at the order of magnitude of 105–106 M ^–1, and the metal complexes can bind to DNA more strongly than the free ligand alone. In addition, antioxidant activities of the ligand and its metal complexes were investigated through scavenging effects for hydroxyl radical in vitro, indicating that the compounds show stronger antioxidant activities than some standard antioxidants, such as mannitol. The ligand and its metal complexes were subjected to cytotoxic tests, and experimental results indicated that the metal complexes show significant cytotoxic activity against lung cancer A 549 cells.     

Ferrocenophanes with Interannular Nitrogen–Gallium Bridges. 1,3,2‐Diazagalla‐[3]Ferrocenophanes and an 1‐Aza‐3‐Azonia‐2‐Gallata‐[3]Ferrocenophane. Synthesis and Structure

1,1′‐Bis(trimethylsilylamino)ferrocene reacts with trimethyl‐ and triethylgallium to give the μ‐[ferrocene‐1,1′‐diyl‐bis(trimethylsilylamido)]tetraalkyldigallanes. These were converted into the 1,3‐bis(trimethylsilyl)‐2‐alkyl‐2‐pyridine‐1,3,2‐diazagalla‐[3]ferrocenophanes, of which the ethyl derivative was characterized by X‐ray structural analysis. Treatment of gallium trichloride with N,N′‐dilithio‐1,1′‐bis(trimethylsilylamino)ferrocene affords μ‐[ferrocene‐1,1′‐diyl‐bis(trimethylsilylamido)]tetrachlorodigallane along with bis(trimethylsilyl)‐2,2‐dichloro‐1‐aza‐3‐azonia‐2‐gallata‐[3]ferrocenophane as a side product, and both were structurally characterized by X‐ray analysis. The solution‐state structures of the new gallium compounds and aspects of their molecular dynamics in solution were studied by NMR spectroscopy (¹H, ¹³C, ²⁹Si NMR).     

Cyclopentadienyl Dicarbonyl Iron‐Bismuth Compounds – Synthesis,Structure, and Reactivity

Abstract. The cyclopentadienyl‐substituted iron‐bismuth complexes [{Cp(CO)₂Fe}BiCl₂] ( 1 ), [{Cp(CO)₂Fe}BiBr₂] ( 2 ), [{Cp′′(CO)₂Fe}BiBr₂] ( 3 ) and [{Cp*(CO)₂Fe}BiBr₂] ( 4 ) were prepared with high yields starting from [Cp^x(CO)₂Fe]₂ [Cp^x = C₅H₅ (Cp), C₅H₃‐1, 3‐tBu₂ (Cp′′), C₅Me₅ (Cp*)] and the corresponding bismuth halides. The single crystal X‐ray structure analyses of compounds 2 – 4 are reported. Comparison of their solubility demonstrates that the steric hindrance in this type of compounds is only slightly higher for compound 3 compared with compound 2 but significantly lower compared with the Cp* derivative 4 . Compounds 1 – 4 react with nucleophililic reagents such as KOtBu, NaOCH₂CH₂OCH₃, and NaOSiMe₃ as well as with water in the presence of an amine to give a mixture of [{Cp^x(CO)₂Fe}BiX] (X = Cl, Br) and [{Cp^x(CO)₂Fe}₃Bi]. In case of a reaction with nBu₄NCl and DMAP (dimethylaminopyridine) no such dismutation is observed. Instead the complexes [{Cp(CO)₂Fe}BiBr₂(DMAP)₂] ( 5 ), [NnBu₄]₂[{{Cp(CO)₂Fe}BiBr₃}₂] ( 6 ) and [NnBu₄]₂[{{Cp(CO)₂Fe}BiCl₃}₂] ( 7 ) were isolated and characterized by single‐crystal X‐ray diffraction.     

Synthesis and structures of photoactive manganese–carbonyl complexes derived from 2‐(pyridin‐2‐yl)‐1,3‐benzothiazole and 2‐(quinolin‐2‐yl)‐1,3‐benzothiazole

PhotoCORMs (photo‐active CO‐releasing molecules) have emerged as a class of CO donors where the CO release process can be triggered upon illumination with light of appropriate wavelength. We have recently reported an Mn‐based photoCORM, namely [MnBr(pbt)(CO)₃] [pbt is 2‐(pyridin‐2‐yl)‐1,3‐benzothiazole], where the CO release event can be tracked within cellular milieu by virtue of the emergence of strong blue fluorescence. In pursuit of developing more such trackable photoCORMs, we report herein the syntheses and structural characterization of two Mn^I–carbonyl complexes, namely fac‐tricarbonylchlorido[2‐(pyridin‐2‐yl)‐1,3‐benzothiazole‐κ²N ,N ′]manganese(I), [MnCl(C₁₂H₈N₂S)(CO)₃], (1), and fac‐tricarbonylchlorido[2‐(quinolin‐2‐yl)‐1,3‐benzothiazole‐κ²N ,N ′]manganese(I), [MnCl(C₁₆H₁₀N₂S)(CO)₃], (2). In both complexes, the Mn^I center resides in a distorted octahedral coordination environment. Weak intermolecular C—H…Cl contacts in complex (1) and Cl…S contacts in complex (2) consolidate their extended structures. These complexes also exhibit CO release upon exposure to low‐power broadband visible light. The apparent CO release rates for the two complexes have been measured to compare their CO donating capacity. The fluorogenic 2‐(pyridin‐2‐yl)‐1,3‐benzothiazole and 2‐(quinolin‐2‐yl)‐1,3‐benzothiazole ligands provide a convenient way to track the CO release event through the `turn‐ON' fluorescence which results upon de‐ligation of the ligands from their respective metal centers following CO photorelease.     

Synthesis and Crystal Structure of [La(phen)2(H2O)2(NO3)2]NO3 · 2(phen)(H2O) with phen = 1,10‐phenanthroline

The title compound [La(phen)₂(H₂O)₂(NO₃)₂](NO₃) · 2(phen)(H₂O) with phen = 1,10‐phenanthroline was prepared by the stoichiometric reaction of La(NO₃)₃ · 6 H₂O and 1,10‐phenanthroline monohydrate in a CH₃OH–H₂O solution. The crystal structure (triclinic, P 1 (no. 2), a = 11.052(2), b = 13.420(2), c = 16.300(2) Å, α = 78.12(1)°, β = 88.77(1)°, γ = 83.03(1)°, Z = 2, R = 0.0488, wR² = 0.1028) consists of [La(phen)₂(H₂O)₂(NO₃)₂]²⁺ complex cations, NO₃^– anions, phen and H₂O molecules. The La atom is 10‐fold coordinated by four N atoms of two bidentate chelating phen ligands and six O atoms of two H₂O molecules and two bidentate chelating NO₃^2– ligands with d(La–O) = 2.522–2.640 Å and d(La–N) = 2.689–2.738 Å. The intermolecular π‐π stacking interactions play an essential role in the formation of two different 2 D layers parallel to (001), which are formed by complex cations and uncoordinating phen molecules, respectively. The uncoordinated NO₃^– anions and H₂O molecules are sandwiched between the cationic and phen layers.     

过渡金属配合物催化的二氧化碳的固定*

综述了利用过渡金属配合物和二氧化碳的配位及插入反应实现二氧化碳固定的基本方法、原理及其研究现状。     

Direct Assembly of 2‐Oxazolidinones by Chemical Fixation of Carbon Dioxide

The reaction of β‐ and γ‐haloamines with carbon dioxide to give pharmaceutically relevant 2‐oxazolidinones and 1,3‐dioxazin‐2‐ones, was found to proceed efficiently in the presence of a base and in the absence of catalyst. After optimization of reaction conditions, the system was successfully expanded to a variety of haloamines, even at multigram scale. The reaction was further studied in silico by DFT calculations.     

Structure and Magnetic Properties of Mononuclear Copper(II) Complexes with 2,2‐Bipyrimidine, 2,3‐Bis(2‐pyridyl)pyrazine,and 4‐Terpyridone Based Ligands

Four new complexes of [Cu(bpm)(ox)(H₂O)] ( 1 ), [Cu(tpd)(dca)(H₂O)] ( 2 ), [Cu(bppz)(N₃)₂] ( 3 ), and [Cu(bpm)₂(μ_1,3‐N₃)(N₃)] ( 4 ) (bpm = 2,2′‐bipyrimidine, bppz = 2,3‐bis(2‐pyridyl)pyrazine, tpd = 4‐terpyridone, dca = dicyanamide, ox = oxalate) have been prepared and characterized by X‐ray single‐crystal analysis and variable‐temperature magnetic measurements. Compounds 1–4 are essentially mononuclear Cu(II) complexes. However, in complex 1 , Cu(II) it was found that intermolecular hydrogen bonding through between H₂O and ox formed 1‐D chain structure. In complex 2 it was found that the hydrogen bonding between H₂O and tpd of the next molecule led to for a binuclear Cu(II) complex. In complex 3 , two nitrogen atoms, one of the pyridyl group of bppz and one of N₃^? ligands, are weakly coordinated to neighbor Cu(II) ion thus leading to formation of a 1‐D chain structure. In complex 4 , one nitrogen atom of terminated N₃^? is weakly coordinated to the neighbor Cu(II) site to form a 1‐D polymeric structure. The magnetic susceptibility measurements indicate that complex 1 and 4 exhibit a weak antiferromagnetic interaction whereas a ferromagnetic coupling has been established for complexes 2 and 3 .     

[PtIn6][GaO4]2 – das erste Oxid mit [PtIn6]‐Oktaedern. Darstellung,Charakterisierung und Rietveldverfeinerung – mit einer Bemerkung zur Mischkristallreihe [PtIn6][GaO4]2–x[InO4]x (0 < x ≤ 1)

[PtIn₆][GaO₄]₂ – The First Oxide Containing [PtIn₆] Octahedra. Preparation, Characterisation, and Rietveld Refinement – With a Remark to the Solid Solution Series [PtIn₆][GaO₄]_2‐x[InO₄]_x (0 < x ≤ 1) The novel oxides [PtIn₆][GaO₄]_2–x[InO₄]_x (0 < x ≤ 1) are formed by heating intimate mixtures of Pt, In, In₂O₃, and Ga₂O₃ in the corresponding stoichiometric ratio in corundum crucibles under an atmosphere of argon (1220 K, 70 h). The compounds are black, stable in air at room temperature, reveal a semiconducting behaviour, and decompose only in oxidizing acids. X‐ray powder diffraction patterns can be indexed by assuming a face centered cubic unit cell with lattice parameters ranging from a = 1001.3(1) pm (x = 0) to a = 1009.3(1) pm (x = 1). According to a Rietveld refinement [PtIn₆][GaO₄]₂ crystallizes isotypic to the mineral Pentlandite (Fm3m, Z = 4, R(profile) = 6.11%, R(intensity) = 3.95%). The characteristic building units are isolated [PtIn₆]¹⁰⁺ octahedra which are linked via [GaO₄]^5– tetrahedra to a three dimensional framework. Starting from [PtIn₆][GaO₄]₂ the substitution of Ga³⁺ ions by larger In³⁺ ions leads to the formation of a solid solution series according to the general formula [PtIn₆][GaO₄]_2–x[InO₄]_x and becomes apparent in an increase of the lattice parameter.     

Synthesis and Crystal Structure of a Novel Dinuclear Copper(II) Complex, [Cu2(phen)2(H2O)2(OH)2](HCO3)2 · 6 H2O with phen = 1,10‐phenanthroline

Dark blue plate‐like crystals of [Cu₂(phen)₂ · (H₂O)₂(OH)₂](HCO₃)₂ · 6 H₂O were obtained from a CH₃OH–H₂O solution containing CuCl₂, 1,10‐phenanthroline (phen), sebacic acid and Na₂CO₃. The crystal structure (triclinic, P 1 (no. 2), a = 8.118(1), b = 9.624(1), c = 10.536(1) Å, α = 81.35(1)°, β = 88.51(1)°, γ = 75.77(1)°, Z = 1, R = 0.0332, wR² = 0.0981 for 4163 observed reflections (F ≥ 2σ(F ) out of 4595 unique reflections) consists of divalent [Cu₂(phen)₂(H₂O)₂(OH)₂]²⁺ complex cations, anionic (HCO₃)₂^2– dimers and H₂O molecules. The divalent complex cations (d(Cu…Cu) = 2.905(1) Å) are centered at inversion centers. The Cu atoms are fivefold square‐pyramidally coordinated by two nitrogen and three oxygen atoms from one bidentate chelating phen ligand, two bridging hydroxide groups and one axial water molecule (d(Cu–N)phen = 2.021(2), 2.024(2) Å; d(Cu–O)_OH = 1.941(1), 1.949(1) Å; d(Cu–O)_H2O = 2.254(2) Å). The divalent complex cations are stacked to form 2 D layers parallel (001) with 1 D π‐π stacking interactions along [100] via the terminal phen rings. The dimeric (HCO₃)₂^2– anions and the hydrogen bonded H₂O molecules are sandwiched between the 2 D layers.     

(PPh4)2[Cl2Re(N3S2)(μ‐NSN)(μ‐N≡ReCl3)]2 – ein Rhenium(VII)‐Komplex mit einer Nitrido‐, einer Dinitridosulfato(II)‐ und einer Rhena‐3,5‐dithia‐2,4,6‐triazino‐Funktion

(PPh₄)₂[Cl₂Re(N₃S₂)(μ‐NSN)(μ‐N≡ReCl₃)]₂ – a Rhenium(VII) Complex with a Nitrido, a Dinitridosulfato(II), and a Rhena‐3,5‐dithia‐2,4,6‐triazino Function The title compound has been prepared from PPh₄[Re^VIICl₄(NSCl)₂] with N(SiMe₃)₃ in dichloromethane solution to give red‐brown single crystals, which were suitable for a crystal structure determination. As a by‐product PPh₄[ReNCl₄] is formed. (PPh₄)₂[Cl₂Re^VII(N₃S₂)(μ‐NSN)(μ‐N≡Re^VIICl₃)]₂ ( 1 ): Space group P2₁/c, Z = 2, lattice dimensions at –80 °C: a = 1280.8(2), b = 1017.5(1), c = 2467.8(3) pm, β = 95.04(1)°, R = 0.049. The complex anion of 1 consists of a planar ReN₃S₂‐heterocycle which is connected with the second rhenium atom by a μ‐nitrido bridge as well as by a μ‐dinitridosulfato(II) ligand to form a planar Re₂(N)(NSN) six‐membered heterocycle. This [Cl₂Re(N₃S₂)(μ‐NSN)(μ‐N≡ReCl₃)]^– unit dimerizes via one of the N‐atoms of the (NSN)^4– ligand to give a centrosymmetric Re₂N₂ four‐membered ring.     

Electrochemical Synthesis and Characterization of Zinc(II) Complexes with [(4‐Methylphenyl)Sulfonyl]‐1H‐Amido‐2‐Phenyl‐2‐Oxazolines

A series of [(4‐methylphenyl)sulfonyl]‐1H‐amido‐2‐phenyl‐2‐oxazoline ligands, HTs‐ROz, has been synthesized by the reaction of substituted 2‐(2‐aminophenyl)oxazolines and p‐toluensulfonyl chloride. The electrochemical oxidation of a sacrificial zinc anode in an acetonitrile solution of the corresponding ligand gave compounds of general formula [Zn(Ts‐ROz)₂]. All complexes have been characterized by microanalysis, IR and ¹H NMR spectroscopy and single‐crystal X‐ray diffraction. In all cases, the metal atom is coordinated by the nitrogen atoms of two monoanionic ligands.     

Cyano‐Bridged ‘Oximato’ Complexes: Synthesis,Structure, and Catalase‐Like Activities

The reaction of the ‘oximato’‐ligand precursor A (Fig. 1) and metal salts with KCN gave two mononuclear complexes [ML(CN)(H₂O)_n](ClO₄) ( 1 and 2 ; L={N‐(hydroxy‐κO)‐α‐oxo‐N′‐[(pyridin‐2‐yl‐κN)methyl[1,1′‐biphenyl]‐4‐ethanimidamidato‐κN′}; M=Co^II ( 1 ), Cu^II ( 2 ); n=2 for Co^II, n=0 for Cu^II; Figs. 2 and 3). The new cyano‐bridged pentanuclear ‘oximato’ complexes [{ML(H₂O)_n(NC)}₄M¹(H₂O)_x](ClO₄)₂ ( 3 – 6 ) and trinuclear complexes [{ML(H₂O)_n(NC)}₂M¹L](ClO₄) ( 7 – 10 ) ([M¹=Mn^II, Cu^II; x=2 for Mn^II, x=0 for Cu^II] were synthesized from mononuclear complexes and characterized by elemental analyses, magnetic susceptibility, molar conductance, and IR and thermal analysis. The four [ML(CN)(H₂O)_n]⁺ moieties are connected by a metal(II) ion in the pentanuclear complexe 3 – 6 , each one involving four cyano bridging ligands (Fig. 4). The central metal ion displays a square‐planar or octahedral geometry, with the cyano bridging ligands forming the equatorial plane. The axial positions are occupied by two aqua ligands in the case of the central Mn‐atom. The two [ML(CN)(H₂O)_n]⁺ moieties and an ‘oximato’ ligand are connected by a metal(II) ion in the trinuclear complexes 7 – 10 , each one involving two cyano bridging ligands (Fig. 5). The central metal ions display a distorted square‐pyramidal geometry, with two cyano bridging ligands and the donor atoms of the tridentate ‘oximato’ ligand. Moreover catalytic activities of the complexes for the disproportionation of hydrogen peroxide (H₂O₂) were also investigated in the presence of 1H‐imidazole. The synthesized homopolynuclear Cu^II complexes 6 and 10 displayed eficiency in disproportion reactions of H₂O₂ producing H₂O and dioxygen thus showing catalase‐like activity.