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1.
A novel hexanuclear copper complex [Cu6(NO3)12(opytrizediam)2(H2O)][(CH3)2CO]0.5(CH3CH2CH2OH)0.5 (1) with a NO3 bridge has been synthesized by reaction of Cu(NO3)2 · 3H2O with the new potentially octadentate ligand opytrizediam in n-propanol/acetone solution (opytrizediam=N,N′-{2,4-di[(di-pyridin-2-yl)amine]-1,3,5-triazine} ethylenediamine). A single-crystal X-ray diffraction analysis showed the presence of six structurally different copper centres. The coordination spheres of four copper(II) ions are best described as square-pyramidal CuN2O3 chromophores while the two other copper(II) ions are in a trigonal-bipyramidal CuN4O environment. Variable-temperature studies on 1 revealed a unique ferromagnetic coupling of two copper(II) ions bridged by a didentate nitrate anion and separated by a distance of 6.391(6) Å, with J=8.6(1) cm−1. 相似文献
2.
Cyclic and acyclic compartmental Schiff bases, their reduced analogues and related mononuclear and heterodinuclear complexes 总被引:1,自引:0,他引:1
[1+1] macrocyclic and [1+2] macroacyclic compartmental ligands (H2L), containing one N2O2, N3O2, N2O3, N4O2 or O2N2O2 Schiff base site and one O2On (n=3, 4) crown-ether like site, have been prepared by self-condensation of the appropriate formyl- and amine precursors. The template procedure in the presence of sodium ion afforded Na2(L) or Na(HL) · nH2O. When reacted with the appropriate transition metal acetate hydrate, H2L form M(L) · nH2O, M(HL)(CH3COO) · nH2O, M(H2L)(X)2 · nH2O (M=Cu2+, Co2+, Ni2+; X=CH3COO−, Cl−) or Mn(L)(CH3COO) · nH2O according to the experimental conditions used. The same complexes have been prepared by condensation of the appropriate precursors in the presence of the desired metal ion. The Schiff bases H2L have been reduced by NaBH4 to the related polyamine derivatives H2R, which form, when reacted with the appropriate metal ions, M(H2R)(X)2 (M= Co2+, Ni2+; X=CH3COO−, Cl−), Cu(R) · nH2O and Mn(R)(CH3COO) · nH2O. The prepared ligands and related complexes have been characterized by IR, NMR and mass spectrometry. The [1+1] cyclic nature of the macrocyclic polyamine systems and the site occupancy of sodium ion have been ascertained, at least for the sodium (I) complex with the macrocyclic ligand containing one N3O2 Schiff base and one O2O3 crown-ether like coordination chamber, by an X-ray structural determination. In this complex the asymmetric unit consists of one cyclic molecule of the ligand coordinated to a sodium ion by the five oxygen atoms of the ligand. The coordination geometry of the sodium ion can be described as a pentagonal pyramid with the metal ion occupying the vertex. In the mononuclear complexes with H2L or H2R the transition metal ion invariantly occupies the Schiff base site; the sodium ion, on the contrary, prefers the crown-ether like site. Accordingly, the heterodinuclear complexes [MNa(L)(CH3COO)x] (M=Cu2+, Co2+, Ni2, x=1; M=Mn3+, x=2) have been synthesised by reacting the appropriate formyl and amine precursors in the presence of M(CH3COO)n · nH2O and NaOH in a 1:1:1:2 molar ratio. The reaction of the mononuclear transition metal complexes with Na(CH3COO) · nH2O gives rise to the same heterodinuclear complexes. Similarly [MNa(R)(CH3COO)x] have been prepared by reaction of the appropriate polyamine ligand H2R with the desired metal acetate hydrate and NaOH in 1:1:2 molar ratio. 相似文献
3.
Ruo-Jie Tao Chong-Zhen Mei Qing-Lun Wang Dai-Zheng Liao 《Inorganica chimica acta》2004,357(7):1985-1990
A dissymmetrical double Schiff base Cu(II) mononuclear complex: CuHL (1) (where H3L is N-3-carboxylsalicylidene-N′-salicylaldehyde-1,2-diaminoethane) and two trinuclear complexes: [CuL(H2O)CoCuL] · H2O · CH3OH (2) and [(CuL)2Ni] · 2H2O (3) have been synthesized and characterized by means of elemental analyses, IR and electronic spectra. The crystal structures of two heterotrinucler complexes were determined by X-ray analysis. Each dissymmetrical cell unit of the complex 2 contains two heterotrinucler neutral molecules. In each neutral molecule, the central Co2+ ion is located at the site of O6 with a distorted octahedral geometry and one terminal Cu2+ ion at the four-coordination site of N2O2, but the other one at the square-pyramidal environment of N2O3. Each dissymmetrical unit of the complex 3 contains a heterotrinucler neutral molecule, whose structure is similar to that of 2 except two terminal Cu2+ ions both at the inner site of N2O2. The magnetic properties of two heterotrinucler complexes have been determined in the temperature range of 5-300 K, which indicate that the interaction between the central Co2+ ion or Ni2+ ion and the outer Cu2+ ions is antiferromagnetic. The exchange integrals are equal to −26.2 cm−1 for 2 and −50.6 cm−1 for 3. 相似文献
4.
Reaction of bis(2-hydroxybenzyl)-1,3-diaminopropane (H2bhbd) with copper(II) perchlorate and copper(II) chloride in methanol, respectively, leads to linear trinuclear clusters, namely [Cu3(bhbd)2(CH3OH)2(ClO4)2] (1) and [Cu3(bhbd)2Cl2](CH3OH)4 (2). These coordination compounds were characterized by X-ray crystallography, UV-Vis, IR and EPR spectroscopy, and magnetic susceptibility measurements. Both complexes have a linear trinuclear array of copper ions bridged by means of phenolato O atoms and separated by a distance of 2.985(4) Å (1) and 2.937(4) Å (2). Strong antiferromagnetic interactions between these adjacent CuII ions govern the magnetochemistry of 1 (J = −303(1) cm−1) and 2 (J = −482(3) cm−1) resulting in S = 1/2 ground states fully populated below 150 K. A correlation between the interaction parameter J and the angles within the trinuclear clusters is proposed. 相似文献
5.
Two new dinuclear isophthalato-bridged copper(II) complexes [Cu2(ntb)2(μ-ipt)](ClO4)2·4CH3OH·0.33H2O (1), [Cu2(bbma)2(μ-ipt)(NO3)(CH3OH)]NO3·CH3OH (2) and one mononuclear complex [Cu(bbma)(ipt)(CH3OH)0.67(H2O)0.33]·2CH3OH (3) containing tetradentate and tridentate poly-benzimidazole ligands were synthesized, where ntb is tris(2-benzimidazolylmethyl)amine, bbma is bis(benzimidazol-2-yl-methyl)amine and ipt is isophthalate dianion. All of the complexes were characterized by elemental analysis, IR spectra and X-ray crystallography. The structures of complexes 1 and 2 consist of μ-ipt bridging two Cu(II) centers in a bis(monodentate) bonding fashion. The coordination geometry around the Cu(II) ions of both compounds has a distorted square pyramidal geometry. The Cu···Cu distances are 9.142 and 10.435 Å for 1 and 2, respectively. Complex 3 has a distorted square pyramidal geometry achieved by the three N-atoms of the bbma ligand, one isophthalate-oxygen atom and one oxygen atom from a coordinated methanol molecule. The magnetic susceptibility measurements at variable temperature over the 2-300 K range for complexes 1 and 2 are reported, with J values to be −0.013 and −0.32 cm−1, respectively. The results show that the two complexes exhibit very weak antiferromagnetic interactions between the dinuclear copper(II) centers. 相似文献
6.
Herein, we report the syntheses, spectral and structural characterization, and magnetic behavior of four new dinuclear terephthalato-bridged copper(II) complexes with formulae [Cu2(trpn)2(μ-tp)](ClO4)2 · 2H2O (1), [Cu2(aepn)2(μ-tp)(ClO4)2] (2), [Cu2(Medpt)2(μ-tp)(H2O)2](ClO4)2 (3) and [Cu2(Et2dien)2(μ-tp)(H2O)](ClO4)2 (4) where tp = terephthalate dianion, trpn = tris(3-aminopropyl)-amin, aepn = N-(2-aminoethyl)-1,3-propanediamine, Medpt = 3,3′-diamino-N-methyldipropylmine and Et2dien = N,N-diethyldiethylenetriamine. The structures of these complexes consist of two μ-tp bridging Cu(II) centers in a bis(monodentate) bonding fashion. The coordination geometry of the Cu(II) ions in these compounds may be described as close to square-based pyramid (SP) with severe significant distortion towards trigonal bipyramid (TBP) stereochemistry in 1. The visible spectra of the complexes in aqueous solutions are in complete agreement with the assigned X-ray geometry around the Cu(II) centers. Also, the solid infrared spectral data for the stretching frequencies of the tp-carboxalato groups, the ν(COO−) reveals the existence of bis(monodentate) coordination mode for the bridged terephthalate ligand. The susceptibility measurements at variable temperature over the range 2-300 K are reported. Despite the same bonding mode of the tp bridging ligand, there has been observed slight antiferromagnetic coupling for the compounds 1 and 4 with J values of −0.5 and −2.9 cm3 K mol−1, respectively, and very weak ferromagnetic coupling for 2 and 3 with J values of 0.8 and 10.1 cm3 K mol−1, respectively. The magnetic results are discussed in relation to other related μ-terephthalato dinuclear Cu(II) published compounds. 相似文献
7.
Horst Kunkely 《Inorganica chimica acta》2004,357(3):888-890
The electronic spectrum of CuII(dps)2 in CH3CN with dps=3,5-diisopropylsalicylate shows a ligand field absorption at λmax=711 nm (ε=140 M−1 cm−1), and a phenolate to Cu(II) ligand-to-metal charge transfer (LMCT) band at λmax=428 nm (ε=950). LMCT excitation of CuII(dps)2 leads to the reduction of Cu(II) to Cu(I). Copper(II) disappears with φ=2.8×10−3 at λirr=436 nm. 相似文献
8.
The pyrazolone derivative N-(1-phenyl-3-methyl-4-propyl-pyrazolone-5)-salicylidene hydrazone (H2L) and its copper(II) complex [Cu2L2CH3OH]·2CH3OH have been both synthesized and characterized by elemental analyses, IR spectroscopy, X-ray crystallography, theoretical calculation and pharmacological testing. It’s found that the Cu(II) complex possesses more powerful anticancer effectivity than that of the ligand. In order to make its anticancer principium clearly, we investigate their structures. In ligand there are several coordination spots, such as N, O atoms, which are close to biological environment. The crystallographic structural analysis of the complex reveals that the two Cu centers display two different coordination patterns. O1, O2, N3, and N4 from the ligand take part in the coordination with Cu atoms, resulting in the formation of the double-nuclear complex. The pharmacological testing results show that the coordination effect improves the antitumor activity of the ligand. The calculated Fukui function for H2L and its deprotonated form L2− predicts that the most probable reactive sites for electrophilic attack are oxygen atoms. The result is agreement well with the experimental data of the crystal structure analyses. 相似文献
9.
The synthesis of an unsymmetrical phenanthroline-based ligand, 2-methyl-9-(3,5-dimethylpyrazolylmethyl)-1,10-phenanthroline (L), and its cupric [Cu(II)] (1) and cuprous [Cu(I)] (2) complexes, are reported. The X-ray structures of each of these Cu complexes show distinct changes in coordination environments consistent with the geometrical preferences of the two oxidation states. In the solid-state, the Cu(II) complex (1) adopts a geometry best described as trigonal bipyramidal, while the Cu(I) complex (2) consists of a single dicationic dimer in which the ligand bridges between two copper ions, separated by 4.26 Å. The two Cu(I) coordination sites differ in 2 with one copper center complexed in a trigonal planar geometry and the other copper in a distorted tetrahedral environment; the latter coordination results from an additional CH3CN ligand. Complex 1 exhibits a reversible redox process at −0.34 V versus Fc/Fc+ in CH3CN, attributable to the Cu2+/Cu+ couple, while the dimeric Cu(I) complex (2) does not display this redox couple on the CV timescale. Over minutes however, complex 1 does oxidize in the presence of dioxygen to 2 in CH3CN. 相似文献
10.
Kowalik-Jankowska T Biega L Kuczer M Konopińska D 《Journal of inorganic biochemistry》2008,102(8):1615-1622
The stoichiometry, stability constants and solution structure of the complexes formed in the reaction of copper(II) with hexapeptide NPTNLH, i.e. the Neobelliera Bullata Trypsin Modulating Oostatic Factor (Neb-TMOF), and its analogues DPTNLH, Ac-NPTNLH and Ac-DPTNLH have been determined by potentiometric, UV-visible, CD and EPR spectroscopic methods. Upon raising pH for Ac-NPTNLH and Ac-DPTNLH peptides, copper(II) coordination starts from the imidazole nitrogen of the His6; afterwards three deprotonated amide nitrogens are progressively involved in metal ions coordination. In a wide pH range of 4.5-8.5 for the NPTNLH and DPTNLH ligands the CuL complex dominates with the imidazole nitrogen of His6 coordinated to form a macrochelate. The N-terminal amino group of the NPTNLH and DPTNLH peptides takes part in the coordination of the metal ion in the CuL, CuH−1L and CuH−2L complexes. However, at pH above 9 the CuH−3L complex with the {NIm, 3N−} coordination mode is formed. For the CuH−2L complex the spectroscopic data clearly indicate the 4N {NH2, CO or COO−, 2N−, NIm} bonding mode with the axial coordination of the N-terminal amine group to the metal ion. 相似文献
11.
Wei-Wei Sun 《Inorganica chimica acta》2009,362(8):2744-13891
A Cu(II) complex with azide and 4-pyridylacrylic acid (4-Hpya), [Cu2(4-pya)2(N3)2(DMF)2] (1) has been synthesized and characterized crystallographically and spectroscopically. This compound consists of binuclear units in which Cu(II) ions are connected through two equatorial-equatorial end-on azido bridges. The Cu(II) dimers are interlinked by 4-pya to generate two-dimensional coordination polymers. Magnetic investigations revealed a relatively strong ferromagnetic interaction through the azide bridges with J = 145 cm−1, and a weak ferromagnetic interdimer interaction through the long but π-conjugated 4-pya ligands. The magneto-structural correlations have been discussed in comparison with other Cu(II) dimers with the same bridging motif. 相似文献
12.
The dinuclear dicarboxylato-bridged copper(II) complexes [Cu2(TPA)2(μ-tp)](ClO4)2 · H2O (1), [Cu2(TPA)2(μ-fum)](ClO4)2 · 2H2O (2) and [Cu2(pmedien)2(μ-fum)(H2O)2](ClO4)2 (3) (tp = terephthalate dianion, fum = fumarate dianion, TPA = tris(2-pyridylmethyl)amine and pmedien = N,N,N′,N″,N″-pentamethyldiethylenetriamine) were synthesized and structurally characterized by X-ray crystallography. The structures of the TPA complexes 1 and 2 consist of μ-tp or μ-fum bridging two Cu(II) centers in a bis(monodentate) bonding fashion. The coordination geometry around the Cu(II) ions in these compounds has a distorted trigonal bipyamidal geometry, TBP with four nitrogen atoms from the TPA ligand and a coordinated oxygen atom supplied by the carboxylate group of the bridged dicarboxylato ligand. Complex 3 has a distorted square pyramidal geometry achieved by the three N-atoms of the pmedien, one fum-carboxylate-oxygen and by an oxygen atom from a coordinated water molecule. The intradimer Cu…Cu distances in these complexes are 11.078(3), 8.663(4) and 9.520(3) Å for 1, 2 and 3, respectively. The electronic spectra of the complexes in aqueous solutions are in complete agreement with the assigned X-ray geometry around the Cu(II) centers. Also, analysis of the infrared spectral data for the ν(COO−) stretching frequencies of the tp-carboxalato groups reveals the existence of the bis(mondentate) coordination mode for the bridged dicarboxylato ligands in compounds 1 and 2. The susceptibility measurements at variable temperature over the 2-300 K range are reported. For 1-3, it has been observed slight antiferromagnetic coupling with J values of −0.8, −3.0 and −2.9 cm−1, respectively. 相似文献
13.
Tulika Ghosh 《Inorganica chimica acta》2010,363(13):3632-411
A dinuclear double helicate of copper(II) with the Schiff base biacetyl bis(benzoylhydrazone) (H2babh) is reported. The solid state physical properties of the dicopper(II) species are compared with that of its mononuclear precursor. The O,N,N,O-donor babh2− shows an unusual bridging coordination mode in [Cu2(μ-babh)2]. Each metal center in the complex is in very similar tetrahedrally distorted square-planar N2O2 coordination sphere assembled by the two halves of the two babh2−. To accommodate the metal centers, two halves of each ligand are twisted along the (CH3)C-C(CH3) bond. 相似文献
14.
Catalin Maxim Traian D. Pasatoiu Victor Ch. Kravtsov Sergiu Shova Christopher A. Muryn Richard E.P. Winpenny Floriana Tuna Marius Andruh 《Inorganica chimica acta》2008,361(14-15):3903-3911
The following Schiff bases were employed as ligands in synthesizing copper(II) and zinc(II) complexes: N-[(2-pyridyl)-methyl]-salicylimine (Hsalampy), N-[2-(N,N-dimethyl-amino)-ethyl]-salicylimine (Hsaldmen), and N-[(2-pyridyl)-methyl]-3-methoxy-salicylimine (Hvalampy). The first two ligands were obtained by reacting salicylaldehyde with 2-aminomethyl-pyridyne and N,N-dimethylethylene diamine, respectively, while the third one results from the condensation of 3-methoxysalicylaldehyde with 2-aminomethyl-pyridine. Four new coordination compounds were synthesized and structurally characterized: [Cu(salampy)(H2O)(ClO4)] 1, [Cu2(salampy)2(H2trim)2] 2 (H2trim? = the monoanion of the trimescic acid), [Cu4(valampy)4](ClO4)4 · 2CH3CN 3, and [Zn3(saldmen)3(OH)](ClO4)2 · 0.25H2O 4. The crystal structure of 1 consists of supramolecular dimers resulted from hydrogen bond interactions established between mononuclear [Cu(salampy)(H2O)(ClO4)] complexes. Compound 2 is a binuclear complex with the copper ions connected by two monoatomic carboxylato bridges arising from two molecules of monodeprotonated trimesic acid. The crystal structure of 3 consists of tetranuclear cations with a heterocubane {Cu4O4} core, and perchlorate ions. Compound 4 is a trinuclear complex with a defective heterocubane structure. The magnetic properties of complexes 1–3 have been investigated. Compound 4 exhibits solid-state photoluminescence at room temperature. 相似文献
15.
The reaction of phenyl 2-pyridyl ketoxime (PhPyCNOH) with Cu(NO3)2·3H2O in methanol results in the chiral trinuclear complex [Cu3(OH)(PhPyCNO)3(NO3) (CH3OH)]·(NO3) (1), which has been characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The structure of 1 exhibits a triangle of Cu(II) ions, centered by a triply bridging hydroxo ligand and with three edge-bridging oximate groups from the three PhPyCNO− ions. Preliminary variable-temperature magnetic susceptibility studies reveal an antiferromagnetically-coupled system showing antisymmetric exchange. Complex 1 crystallizes in an acentric space group (P21) that belongs to a polar point group, which displays second harmonic generation response and ferroelectric behavior, and provides a new strategy for designing functional coordination complexes. 相似文献
16.
《Inorganica chimica acta》2006,359(7):2241-2245
The reaction of N-benzesulfonyl-l-glutamic acid (Bs-glu) with Zn(CH3COO)2 · 2H2O or Co(CH3COO)2 · 4H2O in the presence of imidazole (Im) produced two novel complexes [Zn(Im)2(Bs-glu)]n (1) and [Co(Im)2(Bs-glu)]n (2). Both of the complexes exhibit similar one-dimensional structural motif and coordination environment. Bs-glu adopts the bis-monodentated coordination mode linking two adjacent metal ions. The complex 1 shows intense photoluminescence in the solid state. Magnetic measurements for 2 show that the exchange interaction of the two Co(II) ions is antiferromagnetic. 相似文献
17.
Hydrothermal reactions of Cu(II) salts with 2,4,6-tris(3/4-pyridyl)-1,3,5-triazine (3/4-tpt) and 1,2,4,5-benzenetetracarboxylic acid (H4btec) afforded five novel coordination polymers, namely [Cu4(3-tpt)2(btec)2(H2O)4]n·6nH2O (1), [Cu(3-tpt)2(H2btec)]n (2), [Cu3(3-Htpt)2(H2btec)2(btec)]n·4nH2O (3), [Cu2(4-tpt)3(H2btec)2]n·4nH2O (4), and [Cu3(4-tpt)2(Hbtec)2(H2O)]n·3nH2O (5). These complexes exhibit various polymeric networks due to diverse coordination modes of tpt and H4btec. Complex 1 displays a 3-D metal-organic framework in which 3-tpt is an exo-tridentate ligand and μ4-btec4− coordinates to two square-pyramidal Cu(II) and two square Cu(II) ions. Complex 2 is a 1-D chain coordination polymer which contains μ2-H2btec2− bridge and monodentate 3-tpt. Complex 3 shows a 3-D metal-organic framework constructed from protonated bidentate 3-Htpt+, tridentate H2btec2− and tetradentate btec4−. Complex 4 is a 1-D ladder-like coordination polymer assembled by μ2-H2btec2−, mono- and bidentate 4-tpt. Complex 5 exhibits a porous 3-D metal-organic framework constructing from tridentate 4-tpt and μ3-Hbtec3−. Their thermal stabilities were also investigated. 相似文献
18.
Alessandro Bencini Jean-Pierre Costes Françoise Dahan Javier Garcia-Tojal Federico Totti 《Inorganica chimica acta》2004,357(7):2150-2156
The molecular and electronic structure, along with the magnetic properties of a dinuclear complex in which two copper ions interact through a phenoxo oxygen atom and an oximato group are presented. The complex [CuL3Cu(O2CCH3)]3H2O · 0.5CH3OH (3) crystallizes in the monoclinic space group Cc, with a=28.432(2) Å, b=12.305(1) Å, c=13.159(1) Å and β=99.580(9)°. The X-ray molecular structure shows that the core of the molecule comprising the two metal ions and the seven neighboring donors is nearly planar. The copper(II) ions were found to be antiferromagnetically coupled with a singlet-triplet splitting of 764(4) cm−1. Density Functional Theory (DFT) showed that the magnetic orbitals are largely delocalized towards the bridging area, and an antiferromagnetic interaction in good agreement with the experimental data was computed using the Broken Symmetry (BS) formalism to obtain the energy of the singlet state. 相似文献
19.
Reaction of the zwitterionic imidazolium salt [(CH2COOH)(CH2COO)im] with K2CO3 or BaO in the presence of 18-crown-6 affords the salts [(CH2COO)2im][K(18-crown-6)] and [(CH2COO)2im]2[Ba(18-crown-6)], respectively. Recrystallisation of these crown complexes from the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide, [emim][Tf2N], at a water interface, results in the formation of new salts in which the original anion is replaced by Tf2N−. Single crystal X-ray diffraction has been performed on two of the salts. Notably, the potassium structure containing 18-crown-6 and Tf2N− forms a linear chain coordination polymer that can be regarded as metal organic frameworks (MOFs). Moreover, this study provides insights into the separation of group I and II metal ions using crown ethers in combination with ionic liquids. 相似文献
20.
Violeta Tudor Miguel Julve Yurii A. Simonov Marius Andruh 《Inorganica chimica acta》2005,358(6):2066-2072
A μ-alkoxo-μ-acetato trinuclear copper(II) complex, [Cu3(H2tea)(Htea)(CH3COO)2](ClO4) 1, has been synthesized by reacting copper(II) perchlorate, triethanolamine and sodium acetate. The unit cell contains two centrosymmetric, crystallographically independent trinuclear Cu(II) complexes and two ions. The crystallographically independent trinuclear Cu(II) complexes differ mainly in some of their geometry parameters. The coordination environment of the central copper atom is square-planar, in one trinuclear entity, and elongated octahedral in the other one (in this last case, the coordination number of the central copper atom increases through the semicoordination of an oxygen atom arising from the aminoalcohol). The acetato groups exhibit the classical syn-syn bridging mode. The distances between the copper(II) ions in the two entities are, respectively: 3.043(3) and 3.034(4) Å. The cryomagnetic investigation of 1 reveals a ferromagnetic interaction between the copper(II) ions (J = +84 cm−1), which is due to a countercomplementary effect of the acetato and alkoxo bridges. 相似文献