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1.
Claudio Pettinari Fabio Marchetti Andrey Drozdov Ivan Timokhin Vera Tsaryuk 《Inorganica chimica acta》2004,357(14):4181-4190
The synthesis and characterization of new lanthanide complexes of formulae [M(Q)3(H2O)(EtOH)], NBu4[M(Q)4] and [M(Q)3(L)] (M = Eu or Tb; HQ = 1-phenyl-3-methyl-4-R-pyrazol-5-one: R = cyclopentylcarbonyl, HQ = HQCP; R = cyclopentylpropionyl, HQ = HQEtCP; L = 1,10-phenanthroline (phen) or 4,7-diphenyl-1,10-phenanthroline (bathophen)) are reported. The crystal structure of the tetrakis (β-diketonate) complex [NBu4][Eu(QETCP)4] containing an eight-coordinated Eu atom in a distorted square antiprismatic environment has been determined. Luminescence studies have been performed on selected derivatives: the data suggested a strong influence of the nature of the acyl moiety in Q ligands and of Ph groups in bathophen (with respect to phen) on the luminescence properties. 相似文献
2.
Europium (152,154Eu) was intravenously injected into rats as: (i) the chloride salt at pH 7.4, (ii) the chloride salt at pH 3, (iii) the albumin complex and (iv) the DTPA complex, and tissue uptake was determined 24 h later. For the chlorides, the target organ for uptake was liver (about 60% of dose) whilst europium complexes were rapidly excreted in urine and were predominantly taken up into the kidney (about 0.5% of dose) and bone. Liver uptake of EuCl3, pH 7.4, corresponded to that of a colloidal material with most 152Eu present in the non-hepatocyte population; however, EuCl3, pH 3, was handled in a different manner, with significant uptake by hepatocytes. The differing tissue distributions of EuCl3 and Eu-albumin suggest that plasma albumin does not readily bind injected EuCl3. Renal uptake of europium, although a relatively low proportion of the injected dose, was associated with many subcellular fractions, including lysosomes, suggesting significant intracellular uptake and thus possible retention. 相似文献
3.
Two new zinc complexes, Zn(HL1)2 (1) and [Zn2(H2L2)(OAc)2]2 (2) [H2L1 = Schiff base derived from o-vanillin and (R)-(+)-2-amino-3-phenyl-1-propanol, H3L2 = Schiff base derived from o-vanillin and 2-amino-2-ethyl-1,3-propanediol], have been synthesized and characterized by single crystal X-ray diffraction, elemental analyses, TG analyses, solid fluorescence, IR, UV-Vis and circular dichroism spectra. The structural analysis shows that complex 1 has a right-handed double helical chain along the crystallographic b axis. A homochiral 3D supramolecular architecture has been further constructed by intermolecular C-H··· π, O-H···O and C-H···O interactions. Complex 2 includes two crystallographically independent binuclear zinc molecules. The two binuclear zinc molecules are isostructural. The 2-D sheet supramolecular structure was formed by intermolecular hydrogen bonding interaction. The fluorescence of ligands and complexes in DMF at room temperature are studied. The interactions of two complexes with calf thymus DNA (CT-DNA) are investigated using UV-Vis, CD and fluorescence spectroscopy. The results show that complex 1 exhibits higher interaction with CT-DNA than complex 2. In addition, in vitro cytotoxicity of the complexes towards four kinds of cancerous cell lines (A549, HeLa, HL-60 and K562) were assayed by the MTT method. Investigations on the structures indicated that the chirality and nuclearity of zinc complexes play an important role on cytotoxic activity. 相似文献
4.
Two europium α-thiophene carboxylic acid (HTPA) compounds, coordination polymer Eu(TPA)3(HTPA)2 (1) (TPA=α-thiophene carboxylate) and supramolecular compound Eu(TPA)3(H2O)3 · 0.5H2O (2) with luminescence and triboluminescence, have been synthesized and structurally characterized. In 1 each europium is bridged by six oxygen atoms from six carboxylates and coordinated with two carboxyl oxygen atoms from two α-thiophene carboxylic acid molecules, resulting in a coordination number of eight to Eu. For 2 each europium is chelated by six oxygen atoms from six carboxylates and coordinated with three oxygen atoms from three coordinated water generating a coordination number nine to Eu; A supramolecular compound is constructed through hydrogen bonds. Both 1 and 2 display strong characteristic emission of Eu3+ ion radiated by UV light and produce twinkling red light with an external force. 相似文献
5.
Nans Roques Daniel Maspoch Angela Datcu Jean-Pascal Sutter Jaume Veciana 《Inorganica chimica acta》2007,360(13):3861-3869
Two europium (III) complexes (3 and 4) have been obtained reacting europium (III) nitrate and two polychlorotriphenylmethyl radicals properly functionalized with one (PTMMC−, 1) and six (PTMHC6−, 2) carboxylate groups, respectively. While complex 3 reveals a lamellar polar-apolar separated ion pair structure alternating PTM-based bilayers with nonaaquaeuropium cations ([Eu(H2O)9](PTMMC)3(PTMMCH)3 · 7H2O · 6EtOH), complex 4 shows a one-dimensional chain-like structure with formula [Eu2(PTMHC)(H2O)13] · 16H2O · EtOH. Magnetic properties of both complexes were studied in the 2-300 K range, and show the presence of weak inter-radical antiferromagnetic interactions below 5 K. 相似文献
6.
Three novel europium complexes, Eu(CCHPD)3Phen = Tris[1-(9H-carbazol-9-yl)-3-[(6-(9H- carbazol-9-yl)hexoxy)-phenyl]-1,3-dione](1,10-phenanthroline) europium(III), Eu(CCHPD)3Bath = Tris[1-(9H-carbazol-9-yl)-3-[(6-(9H-carbazol-9-yl)hexoxy)-phenyl]-1,3-dione](bathophenanthroline) europium(III) and Eu(CPD)3Phen = Tris[1-(9H-carbazol-9-yl)-3-phenylpropane]-1,3-dione](1,10-phenanthroline) europium(III), have been synthesized and characterized (Scheme 1). Involved ligands consist of different chelating and non-chelating units: appended carbazole (Br-Carb), phenanthroline (Phen), bathophenanthroline (Bath) and 1-(9H-carbazol-9-yl)-3-phenylpropane]-1,3-dione (CPD). The luminescence properties show that the carbazole moiety is a better sensitizer for the metal centred (MC) emitting states relative to Phen and Bath. Moreover, its charge-transporting properties make such complexes appealing for their application in electroluminescent devices. 相似文献
7.
Synthesis,characterization and luminescent properties of europium complexes with 2,4,6‐tris‐(2‐pyridyl)‐s‐triazine as highly efficient sensitizers
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Jie Kang Ying‐Nan Chen Ai‐Ling Wang Hai‐Yan Li Yan‐Rong Qu Hai‐Xia Zhang Hai‐Bin Chu Yong‐Liang Zhao 《Luminescence》2015,30(8):1360-1366
Using 2,4,6‐tris‐(2‐pyridyl)‐s‐triazine (TPTZ) as a neutral ligand, and p‐hydroxybenzoic acid, terephthalic acid and nitrate as anion ligands, five novel europium complexes have been synthesized. These complexes were characterized using elemental analysis, rare earth coordination titrations, UV/vis absorption spectroscopy and infrared spectroscopy. Luminescence spectra, luminescence lifetime and quantum efficiency were investigated and the mechanism discussed in depth. The results show that the complexes have excellent emission intensities, long emission lifetimes and high quantum efficiencies. The superior luminescent properties of the complexes may be because the triplet energy level of the ligands matches well with the lowest excitation state energy level of Eu3+. Moreover, changing the ratio of the ligands and metal ions leads to different luminescent properties. Among the complexes, Eu2(TPTZ)2(C8H4O4)(NO3)4(C2H5OH)·H2O shows the strongest luminescence intensity, longest emission lifetime and highest quantum efficiency. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
8.
A lanthanide metal coordination polymer [Eu2(BDC)3(DMSO)(H2O)] was synthesized by the reaction of europium oxide with benzene‐1,3‐dicarboxylic acid (H2BDC) in a mixed solution of dimethyl sulfoxide (DMSO) and water under hydrothermal conditions. The crystal structure of Eu2(BDC)3(DMSO)(H2O) was characterized by X‐ray diffraction (XRD). Thermo‐gravimetric analysis of Eu2(BDC)3(DMSO)(H2O) indicated that coordinated DMSO and H2O molecules could be removed to create Eu2(BDC)3(DMSO)(H2O)‐py with permanent microporosity, which was also verified by powder XRD (PXRD) and elemental analysis. Both Eu2(BDC)3(DMSO)(H2O) and Eu2(BDC)3(DMSO)(H2O)‐py showed mainly Eu‐based luminescence and had characteristic emissions in the range 550–700 nm. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
9.
In this paper, we report the synthesis and the characterization of a novel series of lanthanide (III) complexes with two potentially hexadentate ligands.The ligands contain a rigid phenanthroline moiety and two flexible hydrazonic arms with different donor atom sets (NNN′N′OO and NNN′N′N″N″, respectively for H2L1 (2,9-diformylphenanthroline)bis(benzoyl)hydrazone and H2L2 (2,9-diformylphenanthroline)bis(2-pyridyl)hydrazone).Both nitrate and acetate complexes of H2L1 with La, Eu, Gd, and Tb were prepared and fully characterized, and the X-ray crystal structure of the complex [Eu(HL1)(CH3 COO)2] · 5H2O is presented.The stability constants of the equilibria Ln3+ + H2L1 = [Ln(H2L1)]3+ and Ln3+ + (L1)2− = [Ln(L1)]+ (Ln = La(III), Eu(III), Gd(III), and Tb(III)) are determined by UV spectrophotometric titrations in DMSO at t = 25 °C. The nitrate complexes of H2L2 with La, Eu, Gd and Tb were also synthesized, and the X-ray crystal structures of [La(H2L2)(NO3)2(H2O)](NO3), [Eu(H2L2)(NO3)2](NO3) and [Tb(H2 L2)(NO3)2](NO3) are discussed. 相似文献
10.
Eu(NO3)3?5H2O and EuCl3?6H2O were allowed to react with bis(diphenylphosphino)alkane dioxides Ph2P(O)(CH2)nP(O)Ph2 (n = 2, 4, 6) to obtain polymeric and binuclear complexes. The prepared compounds were structurally characterized by X‐ray diffraction. Luminescence measurements (emission and excitation spectra, quantum yields, lifetimes) were compared with crystallographic data in order to find a relationship between luminescent properties of the Eu(III) complexes and their structures. The Eu(III) polymers, especially [Eu(dpphO2)2Cl2]+Cl–}n, have shown extremely long luminescence lifetimes, up to 3.73 ms, as a result of a highly protecting hydrophobic shield. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
11.
S. Tamburini P.A. Vigato M. Gatos L. Bertolo U. Casellato 《Inorganica chimica acta》2006,359(1):183-196
The mononuclear macrocyclic lanthanide(III) complexes, [Ln(H2L)(H2O)4]Cl3 (Ln = Y, La, Ce, Cu, Tb, Yb, Lu; H2L = H2LA, H2LB, H2LC) were prepared by condensation 3,3′-(3,6-dioxaoctane-1,8-diyldioxy)bis(2-hydroxybenzaldehyde) or 3,3′-(3-oxapentane-1,5-diyldioxy)bis(2-hydroxybenzaldehyde) with 1,5-diamino-3-azamethylpentane or 1,7-diamino-3-azamethylheptane in the presence of LnCl3 · nH2O as templating agent. The asymmetric [1+1] ligands H2LA, H2LB and H2LC contain one smaller or larger N3O2 Schiff base site and one crown-ether like O2O4 or O2O3 site. The preference of the lanthanide ion to reside into the Schiff base or the crown-ether like chamber was investigated in the solid state and in methanol or dimethylsulfoxide solution. It was found that in the solid state or in methanol the lanthanide(III) ion coordinates into the O2On site while in dimethylsulfoxide demetalation and partial metal ion migration from the O2On into the N3O2 chamber occur. The mononuclear lanthanide(III) complexes [Ln(H2L)(H2O)4]Cl3 with the Ln3+ ion in the O2On site have been used as ligands in the synthesis of the heterodinuclear complexes LnLn′(L)(Cl)4 · 4H2O by reaction with the appropriate Ln′(III) chloride in methanol and in the presence of base. The related homodinuclear complexes Ln2(L)(Cl)4 · 4H2O have been prepared by the one-pot condensation of the appropriate precursors in the presence of base and of the lanthanide(III) ion as templating agent.The single-crystal X-ray structure of [Eu(H2LA)(H2O)4]Cl3 · 5H2O has been determined. The europium ion is nine-coordinated in the O2O3 ligand site and bonded to four water molecules and the coordination polyhedron can be described as a square monocapped antiprism.The site occupancy of the different lanthanide(III) ions and the physico-chemical properties arising from the different dinuclear aggregation and/or from the variation of the crown-ether shape have been investigated by IR and NMR spectroscopy, MS spectrometry and SEM-EDS microscopy. In particular, site migration and/or transmetalation reactions, together with demetalation reactions, have been monitored by NMR studies in methanol and dimethylsulfoxide. It was found that these processes strongly depend on the shape of the two coordination chambers, the solvent used and the radius of the lanthanide(III) ions. Thus, these molecular movements can be tuned by changing appropriately these parameters. 相似文献
12.
Fei Wang 《Inorganica chimica acta》2010,363(6):1320-3958
Five novel complexes with two pyridine substituted benzotriazole ligands, 1-(2-pyridyl)benzotriazole (L1) and 1-(4-pyridyl)benzotriazole (L2), [Zn(L1)2Cl2] (1), [{Zn(L1)2Cl2}·(L1)2] (2), [Zn(L2)2Cl2] (3), [{Zn(L2)(H2O)3(μ2-SO4)}·H2O] (4), and [{Cd(L2)(H2O)3(μ2-SO4)}·H2O] (5) were synthesized. The details of the structures were characterized by X-ray single crystal analysis, revealing that these complexes were assembled together via supramolecular interaction, such as, hydrogen bonding and π-π interactions. The influence of organic ligands, anions and reaction conditions in the formation of the complexes were investigated. 相似文献
13.
W. Vreugdenhil J. G. Haasnoot M. F. J. Schoondergang J. Reedijk 《Inorganica chimica acta》1987,130(2)
The spectroscopic and magnetic properties are described of coordination compounds with asymmetric 3,4-diakyl substituted 1,2,4-triazoles. The ligands 3-methyl-4-ethyl-1,2,4-traizole and 3-methyl-4-t-butyl-1,2,4-triazole have been investigated. Using M(CF3SO3)2 (M = Mn, Co, Ni, Cu, Zn) compounds have been obtained with a linear trinuclear structure, in which the metal ions are linked to each other by two pairs of three bridging triazoles. The coordination sphere around the terminal ligands is completed by monodentate ligands and/or water molecules. The structure has been confirmed by an X-ray structure determination of [Co3(metz)6(H2O)6][Co3 (metz)8(H2O)4](CF3SO3)12(H2O)8. this compound crystallizes in the space group P
with lattice constants a = 13.793(4), b = 14.401(3), c = 23.258(4) Å, α = 80.58(2), β = 83.23(2) and γ = 64.33(2)°. The unit cell contains two independent trinuclear clusters of different composition. These two clusters have the same overall structure. Differences are related to the presence of monodentately coordinating ligands as well as to the position of the C3-methyl substituent. The complete refinement of this structure was obstructed by disorder problems in the anions and the non-coordinating water molecules. The magnetic susceptibilities of the compounds have been recorded and could be fitted to theoretical expressions for linear trimers. The compound [Ni2- (mtbtz)5(H2O)4](CF3SO3)4(H2O)4 appears to be a dimeric species as concluded from its magnetic behaviour. 相似文献
14.
Oluwatayo F. Ikotun Elizabeth M. Higbee Wayne Ouellette Robert P. Doyle 《Journal of inorganic biochemistry》2009,103(9):1254-1264
Recently, we have observed the emergence of a new series of pyrophosphate-bridged coordination complexes. Such complexes have been prepared by overcoming the ready hydrolysis of the pyrophosphate moiety. To date, no exploration has been conducted on the cytotoxicity of such complexes. Three pyrophosphate-bridged complexes, namely {[Ni(phen)2]2(μ-P2O7)}·27H2O, {[Cu(phen)(H2O)]2(μ-P2O7)}·8H2O and {[Co(phen)2]2(μ-P2O7)}·6MeOH, (where phen is 1,10′-phenanthroline) were chosen for their comparative structural similarities and suitable aqueous solubility. Cytotoxicity studies in the adriamycin-resistant ovarian cancer cell line A2780/AD demonstrated highly significant efficacy, with values as low as 160 pM for the cobalt complex at 72 h. The underlying mechanism for such exceptional toxicity is investigated focusing on DNA interactions, topoisomerase I enzyme inhibition and oxidative stress (followed by intracellular glutathione levels). The role of hydrolysis in uptake and toxicity is also explored (followed by electronic absorption spectroscopy, 31P NMR, and confocal microscopy) and the complexes are compared to cisplatin controls. Overall a clear picture of the extraordinary toxicity emerged. The results demonstrate a new class of prodrugs with significant potential for future development for the treatment of drug-resistant cancer cell lines. 相似文献
15.
Gelson Manzoni de Oliveira Manfredo Hörner Aline Machado Jorge H.S.K. Monteiro 《Inorganica chimica acta》2011,366(1):203-859
Deprotonated 3-(4-nitrophenyl)-1-phenyltriazene N-oxide reacts with YCl3·6H2O and LnCl3·6H2O (Ln = Eu, Ho, Yb) to give the monoclinic chelate complexes [Y{O2N(C6H4)NNN(O)Ph}4](Et3NH)·H2O (1) (Ph = C6H5; Et = C2H5) and [LnIII{O2N(C6H4)NNN(O)Ph}4](Et3NH)·H2O·{CH3OH∗} {LnIII = Eu (2), Ho (3), Yb∗ (4), in which the metal centers present a square antiprismatic configuration. As already observed for hydrated ammonium complexes of triazene-oxides ligands with (C6H4)−NO2 groups, multiple, effective O···H and N···H interactions hold the species in supramolecular 3D assemblies. The optical and the luminescent properties of the triazene-oxide europium complex 2 are also presented and fully discussed. 相似文献
16.
Volatile Eu complexes, namely Eu(TTA)3Phen, Eu(x)Y(1‐x)(TTA)3 Phen; Eu(x)Tb(1‐x)(TTA)3Phen; Eu, europium; Y, yttrium; Tb, Terbium; TTA, thenoyltrifluoroacetone; and Phen, 1,10 phenanthroline were synthesized by maintaining stichiometric ratio. Various characterization techniques such as X‐ray diffraction (XRD), photoluminescence (PL) and thermo gravimetric analysis/differential thermal analysis (TGA/DTA) were carried out for the synthesized complexes. Diffractograms of all the synthesized complexes showed well‐resolved peaks, which revealed that pure and doped organic Eu3+ complexes were crystalline in nature. Of all the synthesized complexes, Eu0.5 Tb0.5(TTA)3Phen showed maximum peak intensity, while the angle of maximum peak intensity for all complexes was almost the same with slightly different d‐values. A prominent sharp red emission line was observed at 611 nm when excited with light at 370 nm. It was observed that the intensity of red emissions increased for doped europium complexes Eu(x)Y(1‐x)(TTA)3Phen and Eu(x)Tb(1‐x)(TTA)3 Phen, when compared with Eu complexes. Emission intensity increased in the following order: Eu(TTA)3Phen > Eu0.5 Tb0.5(TTA)3Phen > Eu0.4 Tb0.6(TTA)3Phen > Eu0.5Y0.5(TTA)3Phen > Eu0.4Y0.6(TTA)3Phen, proving their potential application in organic light‐emitting diodes (OLEDs). TGA showed that Eu complexes doped in Y3+ and Tb3+ have better thermal stability than pure Eu complex. DTA analysis showed that the melting temperature of Eu(TTA)3 Phen was lower than doped Eu complexes. These measurements infer that all complexes were highly stable and could be used as emissive materials for the fabrication of OLEDs. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
17.
Zhi‐Fang Fu Wen‐Xian Li Juan Bai Jin‐Rong Bao Xiao‐fang Cao Yu‐Shan Zheng 《Luminescence》2017,32(3):327-333
This article reports a novel category of coating structure SiO2@Eu(MABA‐Si) luminescence nanoparticles (NPs) consisting of a unique organic shell, composed of perchlorate europium(III) complex, and an inorganic core, composed of silica. The binary complex Eu(MABA‐Si)3·(ClO4)3·5H2O was synthesized using HOOCC6H4N(CONH(CH2)3Si(OCH2CH3)3)2 (MABA‐Si) and was used as a ligand. Furthermore, the as‐prepared silica NPs were successfully coated with the ‐Si(OCH2CH3)3 group of MABA‐Si to form Si–O–Si chemical bonds by means of the hydrolyzation of MABA‐Si. The binary complexes were characterized by elemental analysis, molar conductivity and coordination titration analysis. The results indicated that the composition of the binary complex was Eu(MABA‐Si)3·(ClO4)3·5H2O. Coating structure SiO2@Eu(MABA‐Si) NPs were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM) and infrared (IR) spectra. Based on the SEM and TEM measurements, the diameter of core‐SiO2 particles was ~400 and 600 nm, and the thickness of the cladding layer Eu(MABA‐Si) was ~20 nm. In the binary complex Eu(MABA‐Si)3·(ClO4)3·5H2O, the fluorescence spectra illustrated that the energy of the ligand MABA‐Si transferred to the energy level for the excitation state of europium(III) ion. Coating structure SiO2@Eu(MABA‐Si) NPs exhibited intense red luminescence compared with the binary complex. The fluorescence lifetime and fluorescence quantum efficiency of the binary complex and of the coating structure NPs were also calculated. The way in which the size of core‐SiO2 spheres influences the luminescence was also studied. Moreover, the luminescent mechanisms of the complex were studied and explained. 相似文献
18.
Synthesis and photophysical studies of tetrazolate‐based Eu(III) photoluminescent ternary complexes containing N‐heterocyclic phosphine oxides auxiliary co‐ligands
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Two new ternary tetrazolate Eu(III) complexes with phosphine oxide co‐ligands Eu(PTO)3·(P1/P2) [PTO = 5‐(2‐pyridyl‐1‐oxide)tetrazole, P1 = diphenylphosphorylamino‐phenylphosphoryl‐benzene, P2 = diphenylphosphorylpyridine)‐bis‐isobutyricphosphoryl] were synthesized and characterized using UV, fluorescence, IR and 1H NMR spectroscopic techniques. The analytical data prove that the complexes are mononuclear in nature and the central Eu(III) ion is coordinated by three N and three O atoms of tetrazolate, and two O atoms of the corresponding bidentate phosphine oxide ligands. The ancillary ligand increased the photoluminescence efficiency of Eu(PTO)3·P1 (complex 3) by twofold compared with our previously reported Eu(PTO)3 complex (complex 1). Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
19.
New lanthanide complexes of salicylaldehyde- Schiff bases with salicyloyl hydrazide and anthranilic acid, were synthesized by a novel method consisting of refluxing the mixtures of Schiff base ligands and lanthanide trichloroacetate in acetone. Solid complexes of formulae Ln(SHSASB)3·2H2O and Ln2(AASASB)3·2H2O where Ln = La---Yb and Y, were isolated. Pronto NMR and IR spectra for the complexes reveal the bidentate binding of both the Schiff base ligands to the lanthanide ion. Electronic spectra along with the conductance data for the complexes indicate a coordination number of six for the lanthanide ion in the complexes of both the Schiff bases. 相似文献
20.
C. J. McKenzie H. ToftlundM. PietraszkiewicsZb. Stojek K. Slowinski 《Inorganica chimica acta》1993,210(2)
The 30-membered hexaaza macrocylic ligand, L (L=3,7,11,18,22,26-hexaazatricyclo-[26.2.2.213,16]tetratriaconta-1(31),13(33),14,16(34),28(32),29-hexaene), is capable of forming binuclear complexes with the divalent transition metal ions Ni, Cu and Zn. The two metal ions are bound by the two dipropylenetriamine units of the macrocycle. Extra coordination sites on the metal ions can be occupied by exogenous ligands such as acetate, chloride and thiocyanate. The crystal structure of one of the di-copper complexes is described: [LCu2(CH3CO2)2](ClO4)2·5H2O crystallizes in the monoclinic space group P21/c (No. 14), with a=9.369(2), b=17.644(3), c= 27.466(3) Å, β=92.90(1)°, U=4534.7 Å3 and Z=4. The Cu1···Cu2 separation is 8.40(3) Å. The access for potential exogenous bridging ligands, to the cavity between the copper ions, is somewhat restricted by the two phenyl units of the macrocycle which appear almost parallel in the structure. The redox potential of the couple L(Cu2+)2/L(Cu+)2, recorded by cyclic voltammetry for the chloride adduct, [LCu2Cl2]Cl2·5H2O, is −0.061 V versus SCE in DMF. 相似文献