Synthesis, crystal structures, and properties of inorganic-organic hybrid complexes constructed from copper(II) macrocyclic fragment

Reaction of a macrocyclic copper(II) complex [Cu(L)](ClO₄)₂ · 3H₂O (I) (L = 1,3,10,12,16,19-hexaazatetracyclotetracosane) with a hexapod carboxylate ligand H₆TTHA (H₆TTHA = 1,3,5-triazine-2,4,6-triamine hexaacetic acid) and a tripod carboxylate ligand H₃TATB (H₃TATB = 4,4′,4″-S-triazine-2,4,6-triyl-tribenzoic acid) yielded two mononuclear copper(II) complexes [Cu(L)][H₄TTHA] · 4H₂O (II) and [Cu(L)][HTATB] · 4H₂O (III). The complexes I–III have been structurally characterized. The crystal structures of complexes II and III show the copper(II) ion has a distorted pentacoordinate square-pyramidal geometry with two secondary and two tertiary amines from the macrocyclic complex [Cu(L)]²⁺ and one oxygen atom from the carboxylate ligand group at the axial position. The UV-Vis spectra are utilized to discuss the hydrolysis of the complex II.     

Synthesis, characterization and structures of copper(II) complexes containing carboxylate and sulfonate groups

Four copper(II) complexes containing Schiff base and reduced Schiff base ligands derived from pyridine-2-aldehyde and amino acid containing carboxylate and sulfonate functional groups (N-(2-pyridylmethylene)-amino acid and N-(2-pyridylmethyl)-amino acid, (amino acids = ??-alanine and aminoethanesulfonic acid) namely, [Cu(Pbals)(H₂O)₂]ClO₄·H₂O 1, [Cu(Pbal)(ClO₄)(H₂O)] 2, [Cu₂(Paes)₂(ClO₄)₂]·2H₂O 3, and [Cu(Pae)(H₂O)]·ClO₄·H₂O 4 have been synthesized and characterized. The structural features of carboxylate and sulfonate donor groups have been elucidated. These copper(II) complexes demonstrate different coordination behaviour of the carboxylate and sulfonate groups. Carboxylate groups in complexes 1 and 2 bridge the metal centers and facilitate the formation of 1D helical coordination polymeric structures. In compound 3, the sulfonate groups bridge the metal centers to form a discrete dinuclear complex. In 4, the sulfonate groups link the neighbouring metal centers to form a 1D coordination polymeric structure.     

Synthesis,crystal structure,and electrochemical properties of Ni(II) and Cu(II) complexes with two unsymmetrical N2O2 Schiff base ligands

Nickel(II) and copper(II) complexes of two unsymmetrical tetradentate Schiff base ligands [Ni(Me-salabza)] (1), [Cu(Me-salabza)] (2) and [Ni(salabza)] (3), {H₂salabza = N,N′-bis[(salicylidene)-2-aminobenzylamine] and H₂Me-salabza = N,N′-bis[(methylsalicylidene)-2-aminobenzylamine]}, have been synthesized and characterized by elemental analysis and spectroscopic methods. The crystal structures of 2 and 3 complexes have been determined by single crystal X-ray diffraction. Both copper(II) and nickel(II) ions adopt a distorted square planar geometry in [Cu(Me-salabza)] and [Ni(salabza)] complexes. The cyclic voltammetric studies of these complexes in dichloromethane indicate the electronic effects of the methyl groups on redox potential.     

Synthesis,characterization,structures and magnetic property of chiral oxalate-bridged dicopper(Ⅱ) complexes

The oxalato-bridged dicopper(II) complexes [Cu2(μ-ox)(LRR)2(H2O)2(ClO4)2] (1),[Cu2(μ-ox)(LRR)2(CH3COCH3)2(ClO4)2](1a),[Cu2(μ-ox)(LSS)2(H2O)2(ClO4)2] (2) and [Cu2(μ-ox)(LRR)(LSS)2(CH3COCH3)2(ClO4)2] (3) [LRR = (8R,10R)-(-)-[4,5]-pineno2,2′-bipyridine,LSS = (8S,10S)-(+)-[4,5]-pineno-2,2′-bipyridine;ox2= oxalate] were first prepared.A possible mechanism for the formation of the chial dicopper(II) complexes was proposed.Based on elemental analysis,conductance measurement,UV-Vis spectra,CD spectra and X-ray single-crystal diffraction,the oxalato-bridged structures of 1 and 2 were deduced to adopt two Cu(II) ions and the bridged oxalate lying in the nearly same plane.The crystal structures of 1a and 3 reveal that the coordination geometry around each Cu(II) ion is an elongated and distorted octahedron and two axial solvent molecules and two perchlorate ions are anti to each other respectively in both binuclear molecules.The solution CD spectra of 1 and 2 in the visible d-d range show very weak Cotton effects with peaks at 588 and 779 nm,which are approximately of mirror image,suggesting the optical activities may be derived from the vicinal effects of the chiragenic centers at the pinene group of LRR and LSS,respectively.Complex 1 has been characterized by variable-temperature magnetic susceptibility and the data was least-square fitted to the Blenaey-Bowers equation.The exchange integral J was found to be -338.41(4) cm-1,indicating a strong antiferromagnetic interaction between two copper(II) ions.     

Syntheses, structures, and properties of the Co(II), Ni(II), and Cu(II) complexes with 5-carboxy- and 5-methoxycarbonylpyrazoles

New cobalt(II), nickel(II), and copper(II) complexes based on 5-methoxycarbonyl-3-me-thylpyrazole (MePzCOOMe), [Co(MePzCOOMe)₂(H₂O)₂](NO₃)₂ (I), [Ni(MePzCOOMe)₂(H₂O)₂] (NO₃)₂ (II), and [Cu(MePzCOO)₂(H₂O)] · 3H₂O (III), were synthesized. The compounds were studied by X-ray diffraction analysis, IR spectroscopy, and static magnetic susceptibility. The molecular and crystal structures of complexes I and III were determined by X-ray structure analysis.     

Synthesis,characterization, spectrophotometric and electrochemistry studies,and DNA cleavage of copper(II) complexes of a new azacrown bis-macrocycle and its mono-cyclic analogue

A new azacrown bis-macrocycle (5) and its mono–cyclic analogue (7) were synthesized and characterized by FT-IR, ¹H NMR, ¹³C NMR, DEPT ¹³C NMR, MS, and elemental analysis. The reaction with copper(II) nitrate yielded the corresponding complexes, formulated as Cu(5)(NO₃)₂·3H₂O (8), and Cu(7)(NO₃)₂·2.5H₂O (9). Also the stoichiometries of the complexes were determined in alcoholic solution and the results show that for both complexes the ratio of ligand to metal was 1:1 in methanol. The redox behavior of both complexes has been studied by cyclic voltammetry in DMF. Cyclic voltamogram of 8 shows quasi-reversible Cu^II/Cu^I redox couple whereas 9 shows a reversible Cu^II/Cu^I redox couple. Mono- and bis-macrocycle copper(II) complexes (8 and 9 respectively) cleaved plasmid pGS2 DNA by using an oxidative mechanism with 3- mercaptopropionic acid (MPA) as the reductant under aerobic conditions. The bis-macrocycle copper(II) complex 8 showed higher cleavage efficiency than their mono-macrocycle analogue 9 at the same Cu²⁺ concentration.     

Copper(II) complexes with N,N-dimethylbiguanide

The N,N-dimethylbiguanide (HDMBG) complexes [Cu₂(HDMBG)₂Cl₄] (1) and respectively [Cu(HDMBG)₂]Cl₂·2H₂O (2) exhibit in vitro antimicrobial activity. The complexes were characterised by IR, electronic as well as EPR spectra. The IR spectra of complexes show the pattern of N,N-dimethylbiguanide coordinated as chelate. The electronic and EPR data are in agreement with a square pyramidal stereochemistry for (1) and a square planar one for (2). The in vitro qualitative and quantitative antimicrobial activity assays showed that the complexes exhibited variable antimicrobial activity against Gram-negative strains (Escherichia coli, Klebsiella spp. and Enterobacter sp.) isolated from the hospital environment. The thermal analysis has evidenced the thermal intervals of stability and also the thermodynamic effects that accompany them. The thermal behaviour in nitrogen is complex according to TG and DTA curves including melting, dehydration as well as compounds decomposition.     

Studies on Co(II) and Cu(II) complexes of a ligand derived from 1,3-phenylenediamine and 5-bromosalicylaldehyde synthesis, characterisation, thermal properties and use as new precursors for preparation cobalt and copper oxide nano-particles

A symmetric tetradentate Schiff base ligand, N,N′-bis(5-bromosalicylaldehyde)-1,3-phenylenediamine [(Brsal)₂-1,3-phen) and its Cu(II) and Co(II) complexes with general formula M₂((Brsal)₂-1,3-phen)₂, where M=Co (1) and Cu (2)], have been synthesized and characterized by elemental analyses and FTIR spectroscopy. In addition, Schiff base ligand has been characterized by ¹HNMR spectroscopy. Thermogravimetric analysis of the ligand and its metal complexes reveals their thermal stability and decomposition pattern.     

Mononuclear copper(II) complexes of bis-triazole-based macrocyclic Schiff base hydrazones: direct synthesis,EPR studies,magnetic and thermal properties

Mononuclear copper(II) complexes of 1,2,4-triazole-based Schiff base macrocyclic hydrazones, III and IV, have been reported. The prepared amorphous complexes have been characterized by spectroscopic methods, electron spray ionization mass spectrometry, and elemental analysis data. Electrochemical studies of the complexes in DMSO show only one quasi-reversible reduction wave at +0.43 V (ΔE = 70 mV) and +0.42 V (ΔE = 310 mV) for III and IV, respectively, which is assigned to the Cu(II) → Cu(I) reduction process. Temperature dependence of magnetic susceptibilities of III and IV has been measured within an interval of 2–290 K. The values of χ_M at 290 K are 1.72 × 10^?3 cm³ mol^?1 and 1.71 × 10^?3 for III and IV, respectively, which increases continuously upon cooling to 2 K. EPR spectra of III and IV in frozen DMSO and DMF were also reported. The trend g_|| > g⊥ > g_e suggests the presence of an unpaired electron in the d_x2?y2 orbital of the Cu(II) in both complexes. Furthermore, spectral and antimicrobial properties of the prepared complexes were also investigated.     

Solvent-free synthesis,x-ray studies and in vitro inhibitory activities of copper(II) complexes of non-steroidal anti-inflammatory drugs

Solid-state mechanochemical synthesis of [Cu(CAF)₂(H₂O)(OAc)]OAc complex 1a and [Cu(COD)₂(H₂O)(OAc)]OAc complex 2a were obtained by grinding stoichiometric amounts of Cu(CH₃COO)₂·H₂O and corresponding non-steroidal anti-inflammatory drugs[(caffeine (CAF) and codeine(COD)], respectively, in a mortar with pestle. Solvent-based synthesis of 1b and 2b was also carried out by reaction of metal acetate salt and each drug by refluxing at 70 °C in CH₃OH for 1 h for comparison purposes. The complexes 1a and 2a were characterized by comparison of elemental analysis, FT-IR, UV–Vis and ¹H NMR spectra with those of the free ligand and solvent-based products (1b and 2b). The analytical and spectroscopic data of the complexes prepared via the two different methods are almost identical. X-ray diffraction patterns of the complexes prepared by mechanochemical method were different from that of the starting material suggesting formation of new metal complexes. In vitro inhibitory activities of both mechanochemical and solvent-based complexes were found to be higher than parent ligands, indicating that the antimicrobial effect of these drugs could be enhanced when they are chelated to the metal. The mechanochemical synthesis was carried out without the use of solvent or external heating. The method is faster and gives a higher yield than corresponding solvent-based reactions. The solid state reaction presented higher efficiency in terms of materials, energy and time compared to solvent-based synthesis.     

Co(II), Ni(II) and Zn(II)-orotate complexes with N-methylimidazole: Synthesis, crystal structures and antimicrobial activities

Three Co(II), Ni(II) and Zn(II) complexes of orotate with the N-methylimidazole ligand were synthesized and characterized by means of elemental and thermal analysis, magnetic susceptibilities, IR, UV-Vis spectroscopic and antimicrobial activity studies. The crystal structures of [Co(HOr)(H₂O)₂(Nmeim)₂]₃·H₂O (1), [Ni(HOr)(H₂O)₂(Nmeim)₂] (2) and [Zn(HOr)(H₂O)(Nmeim)₂] (3) were determined by the single crystal X-ray diffraction technique (H₃Or = orotic acid and Nmeim = N-methylimidazole). In complexes 1 and 2, the Co(II) and Ni(II) ions have distorted octahedral geometries with two Nmeim, one orotate and two aqua ligands. Complex 3 has a distorted trigonal bipyramidal geometry with two N-methylimidazole, one orotate and one aqua ligands. In the complexes, the orotate is coordinated to the metal(II) ions through the deprotonated nitrogen atom of the pyrimidine ring and the oxygen atom of the carboxylate group as a bidentate ligand. The complexes form a three-dimensional framework by hydrogen bonding, C-H?π and π?π stacking interactions. The MIC values of the complexes against selected microorganisms were determined to be in range 300-2400 μg/mL.     

Palladium(II) and platinum(II) saccharinate complexes containing pyridine and 3-acetylpyridine: Synthesis, crystal structures, fluorescence and thermal properties

New palladium(II) and platinum(II) complexes of saccharinate (sac), trans-[Pd(py)₂(sac)₂] (1), cis-[Pt(py)₂(sac)₂] (2), trans-[Pd(3-acpy)₂(sac)₂] (3) and cis-[Pt(3-acpy)₂(sac)₂] (4) (py = pyridine and 3-acpy = 3-acetylpyridine) have been synthesized. Elemental analysis, UV-Vis, IR, NMR and TG/DTA characterizations have been carried out. The structures of 1-4 were determined by X-ray diffraction. The palladium(II) and platinum(II) ions are coordinated by two N-bonded sac ligands, and two nitrogen atoms of py or 3-acpy, forming a distorted square-planar geometry. The palladium(II) complexes (1 and 3) are trans isomers, while the platinum(II) complexes (2 and 4) are cis isomers. The mononuclear species in the solid state are connected by weak intermolecular C-H?O hydrogen bonds, C-H?π and π?π stacking interactions. The platinum(II) complexes show significant fluorescence at the room temperature.     

Copper(II) and manganese(II) picrate complexes with the V-shaped ligand 1,3-bis(1-methylbenzimidazol-2-yl)-2-thiapropane: preparation,structure, DNA-binding properties and antioxidant activities

A V-shaped ligand, 1,3-bis(1-methylbenzimidazol-2-yl)-2-thiapropane (L), and its copper(II) and manganese(II) picrate complexes have been synthesized and characterized. The compositions of the complexes are [Cu(L)₂](pic)₂·2DMF (1) and [Mn(L)(pic)₂] (2), respectively. The crystal structure of complex 1 reveals a distorted tetrahedral geometry provided by four N donors from two ligands. Complex 2 is six coordinated, with a distorted octahedral geometry. Experimental studies of the DNA-binding properties indicated that the free ligand and both complexes bind to DNA via the intercalation mode, and the order of the binding affinity is L > 1 > 2. Antioxidant tests in vitro show that the Cu(II) complex possesses significant antioxidant activity against superoxide and hydroxyl radicals, with better scavenging effects than mannitol and vitamin C.     

Synthesis, characterization, electrochemical studies, and antibacterial activities of cobalt(III) complexes with Salpn-Tipe Schiff base ligands. Crystal structure of trans-[CoIII(L1)(Py)2]ClO4

The synthesis, characterization, spectroscopic and electrochemical properties of trans-[Co^III(L¹)(Py)₂]ClO₄ (I) and trans-[Co^III(L²)(Py)₂]ClO₄ (II) complexes, where H₂L¹ = N,N′-bis(5-chloro-2-hydroxybenzylidene)-1,3-propylenediamine and H₂L² = N,N′-bis(5-bromo-2-hydroxybenzylidene)-1,3-propylenediamine, have been investigated. Both complexes have been characterized by elemental analysis, FT-IR, UV-Vis, and ¹H NMR spectroscopy. The crystal structure of I has been determined by X-ray diffraction. The coordination geometry around cobalt(III) ion is best described as a distorted octahedron. The electrochemical studies of these complexes revealed that the first reduction process corresponding to Co(III/II) is electrochemically irreversible accompanied by dissociation of the axial Co-N(Py) bonds. The in vitro antimicrobial activity of the Schiff bse ligands and their corrsponding complexes have been tested against human pathogenic bacterias such as Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli. The cobalt(III) complexes showed lower antimicrobial activity than the free Schiff base ligands.     

Synthesis, crystal structure, spectroscopic and photoluminescence studies of manganese(II), cobalt(II), cadmium(II), zinc(II) and copper(II) complexes with a pyrazole derived Schiff base ligand

Varying coordination modes of the Schiff base ligand H₂L [5-methyl-1-H-pyrazole-3-carboxylic acid (1-pyridin-2-yl-ethylidene)-hydrazide] towards different metal centers are reported with the syntheses and characterization of four mononuclear Mn(II), Co(II), Cd(II) and Zn(II) complexes, [Mn(H₂L)(H₂O)₂](ClO₄)₂(MeOH) (1), [Co(H₂L)(NCS)₂] (2), [Cd(H₂L)(H₂O)₂](ClO₄)₂ (3) and [Zn(H₂L)(H₂O)₂](ClO₄)₂ (4), and a binuclear Cu(II) complex, [Cu₂(L)₂](ClO₄)₂ (5). In the complexes 1-4 the neutral ligand serves as a 3N,2O donor where the pyridine ring N, two azomethine N and two carbohydrazine oxygen atoms are coordinatively active, leaving the pyrazole-N atoms inactive. In the case of complex 5, each ligand molecule behaves as a 4N,O donor utilizing the pyridine N, one azomethine N, the nitrogen atom proximal to the azomethine of the remaining pendant arm and one pyrazole-N atom to one metal center and the carbohydrazide oxygen atom to the second metal center. The complexes 1-4 are pentagonal bipyramidal in geometry. In each case, the ligand molecule spans the equatorial plane while the apical positions are occupied by water molecules in 1, 3 and 4 and two N bonded thiocyanate ions in 2. In complex 5, the two Cu(II) centers have almost square pyramidal geometry (τ = 0.05 for Cu1 and 0.013 for Cu2). Four N atoms from a ligand molecule form the basal plane and the carbohydrazide oxygen atom of a second ligand molecule sits in the apex of the square pyramid. All the complexes have been X-ray crystallographically characterized. The Zn(II) and Cd(II) complexes show considerable fluorescence emission while the remaining complexes and the ligand molecule are fluorescent silent.     

Thermoanalytical,magnetic and structural investigation of Co(II) complexes with dipyridylamine and 2-hydroxyphenones

The simultaneous TG/DTG–DTA technique was used for three new cobalt(II) complexes with dipyridylamine (dpamH) and the anion of a 2-hydroxyphenone ligand (phenone), with the general formula [Co(dpamH)₂(phenone)]Br, in order to determine their thermal degradation in static air and dynamic nitrogen atmospheres, which was found to be a multi-step decomposition related to the release of the ligand molecules. The complexes were characterized by elemental analyses, FT-IR and UV–Vis spectroscopy, magnetic and conductivity measurements. All structures were determined by X-ray crystallography revealing octahedral coordination of cobalt(II) and monomeric nature of the compounds, [Co(dpamH)₂(2-OH-acetophenone)]Br (1), [Co(dpamH)₂(2-OH-propiophenone)]Br (2) and [Co(dpamH)₂(2-OH, 5-CH₃-acetophenone)]Br·EtOH (3). The variable temperature (76–303 K) magnetic susceptibility measurements showed a paramagnetic nature of the complexes, in accordance with their molecular structure.     

Synthesis, characterization, crystal structures, and solution studies of Ni(II), Cu(II) and Zn(II) complexes obtained from pyridine-2,6-dicarboxylic acid and 2,9-Dimethyl-1,10-Phenanthroline

The homonuclear water-soluble and air stable compounds (dmpH) (H₅O₂) au][M(pydc)₂].0.5H₂O (M = Ni(II) (1), Cu(II) (2), Zn(II) (3); pydcH₂ = pyridine-2,6-dicarboxylic acid, dipicolinic acid, dmp = 2,9-dimethyl-1,10-phenanthroline) have been prepared by self-assembly synthesis in aqueous solution at room temperature, and characterized by IR, ¹H NMR, ¹³C NMR, elemental analysis and X-ray diffraction single crystal analyses for 1, 2 and 3. The complexes 1–3 represent the isostructural features. Extensive hydrogen bonding interactions involving all aqua ligands, dipicolinate oxygens and lattice water molecules further stabilize the complex units by linking them to form three dimensional polymeric networks. The stoichiometry and stability of the all three complexes in aqueous solution were investigated by potentiometric pH titration.     

Two new cyano-bridged Cu(II)-Fe(II) complexes: Synthesis and crystal structures

Two new cyano-bridged Cu(II)-Fe(II) binuclear complexes, [Cu(L¹)Fe(CN)₅(NO)] (I) [L¹ = 1,3,6,8,11,14-hexaazatricyclo[12.2.1.1^8,11]octadecane and [Cu(L²)Fe(CN)₅(NO)] · 2H₂O (II) L² = 1,3,6,9,11,14-hexaazatricyclo[12.2.1.1^6,9]octadecane, have been assembled and structurally characterized by spectroscopy and X-ray crystallography. Complex I crystallizes in the monoclinic crystalline system of space group P2₁/c, while complex II crystallizes in the monoclinic crystalline system of space group P2₁/n. These two complexes assume a binuclear structure in which the Fe²⁺ ion is in an octahedron environment and the Cu²⁺ ion is in a square-prism geometry environment.     

On the structure of Zn(II) and Cu(II) cyanin complexes in aqueous solution

B3LYP/6-31++G(d,p) optimizations on models for the metal cyanin, Cy, complexes [MCy(H₂O) _n ]⁺, (M = Zn(II), Cu(II); n = 2, 3, 4) in aqueous solution indicate that 4 is the most favoured coordination number in both cases. SP -4 and T -4 geometries are nearly isoenergetic for the former, while SP -4 is the only one obtained for the latter. Anionic cyanin displays higher affinity for Cu(II) than for Zn(II) or Mg(II). The electron density reorganization of cyanin model accompanying the complexation process was analyzed by means of the quantum theory of atoms in molecules. This analysis reveals that: (1) the O4′–M bond is stronger than O3′–M; (2) anionic cyanin displays a dual character between 4′-keto-quinoidal and 3′,4′-dienolate resonance forms; (3) Cu(II) takes more electron density than Zn(II) from Cy^? and water ligands; (4) when the coordination number increases, each ligand (Cy^? or water) transfers less electron density; (5) complex formation modifies the electron density in all the atoms of the ligands, but the largest modifications are displayed within the AC bicycle of Cy^?; and (6) a third part of density lost by the Cy^? ligand is removed from hydrogens.     

Comparative investigation of the copper(II) complexes of (R)-, (S)- and (R,S)-1-phenyl-N,N-bis(pyridine-3-ylmethyl)ethanamine along with the related complex of (R,S)-1-cyclohexyl-N,N-bis(pyridine-3-ylmethyl)ethanamine. Synthetic, magnetic, and structural studies

The interaction of the enantiopure (R)- and (S)-1-phenyl-N,N-bis(pyridine-3- ylmethyl)ethanamine ligands, R-L ¹ and S-L ¹ , with copper(II) chloride followed by addition of hexafluorophosphate resulted in the isolation of the corresponding enantiomeric complexes [Cu(R-L ¹ )Cl](PF₆) (1), [Cu(S-L ¹ )Cl](PF₆) (2) and [Cu(S-L ¹ )Cl](PF₆)??0.5Et₂O (3), in which dimerization occurs through two long Cu??????Cl interactions, the ??-chloro bridges being thus strongly asymmetric. The organic ligand is bound to the metal centre via its N₃-donor dipyridylmethylamine fragment in a planar fashion, such that each copper centre is in a square planar environment (or distorted square pyramidal with a long axial bond length if the additional interaction is considered). When R,S-L ¹ was employed in a parallel synthesis, the similar racemic complex [Cu(R,S-L ¹ )Cl](PF₆)??0.5MeOH (4) was obtained, in which the L ¹ ligands in each dimeric unit have opposite hands. In contrast to the complexes of L ¹ , the reaction of Cu(II) chloride with the related ligand, (R)-1-cyclohexyl-N,N-bis(pyridine-3-ylmethyl)ethanamine (R-L ² ), yielded the mononuclear complex [Cu(R,S-L ² )Cl₂] (5), displaying a distorted square pyramidal coordination geometry. The structure of this product along with its corresponding circular dichroism spectrum revealed that racemisation of the starting R-L ² ligand has occurred under the relatively mild (basic) conditions employed for the synthesis. A temperature-dependent magnetic studies of the complexes 1, 2 and 5 indicate that a week ferromagnetic interaction is operative in each dicopper core in 1 and 2 with 2J?=?1.2?cm^?1. On the other hand, a week antiferromagnetic intermolecular interaction is operative for 5.