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1.
The synthesis, crystal structure and magnetic properties of manganese(III) binuclear complexes [MnIII2(L-3Н)2(CH3ОH)4]·2CH3ОH (1) and [MnIII2(L-3Н)2(Py)4]·2Py (2) (L = 3-[(1E)-N-hydroxyethanimidoyl]-4-methyl-1H-pyrazole-5-carboxylic acid) are reported. The ligand contains two distinct donor compartments formed by the pyrazolate-N and the oxime or the carboxylic groups. The complexes were characterized by X-ray single crystal diffraction, revealing that both 1 and 2 consist of dinuclear units in which the two metal ions are linked by double pyrazolate bridges with a planar {Mn2N4} core. Cryomagnetic measurements show antiferromagnetic interaction with g = 1.99, J = −3.6 cm−1, Θ = −2.02 K for 1 and g = 2.00, J = −3.7 cm−1, Θ = 1.43 K for 2.  相似文献   

2.
《Inorganica chimica acta》1986,122(2):199-205
The X-ray structures of two binuclear copper(II) chloride complexes of the tetradentate ligands 1,4- bis(4,6-dimethyl-2-pyridylamino)phthalazine (PAP46Me) and 3,6-bis(2-pyridylthio)pyridazine are reported. [Cu2(PAP46Me)Cl4] (1) and [Cu2(PTP)Cl4]· CH3CH2OH (2) contain triply bridged binuclear centres involving a diazine (NN) and two chlorobridges with copper-copper separations in the fange 3.19–3.25 Å and distorted square pyramidal copper stereochemistry. The reduced room temperature magnetic moments indicate antiferromagnetically coupled binuclear copper(II) centres.Complex 1 forms green crystals with a= 15.795(3), b=10.661(3), c=16.155(4) Å, β= 113.82(3)°, C2/c, Z = 4, Rf=0.031. Complex (2) forms green crystals with a=33.9022(8), b= 9.1626(5), c= 15.7885(5) Å,β= 114.853(2)°, C2/c, Z=8, Rf=0.047. The structure of the ligand PTP is also reported and compared with that of 2.  相似文献   

3.
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 13 have been investigated. Compound 4 exhibits solid-state photoluminescence at room temperature.  相似文献   

4.
《Inorganica chimica acta》2006,359(4):1071-1080
The preparation and characterization of two novel amino-incorporated sulfur-bridged dinuclear iron (I) complexes of the type [NR(μ-SCH2)2]Fe2(CO)6, one being amino protected [N(CH2CH2NHTs)(μ-SCH2)2]Fe2(CO)6 (8) and the other [(μ- SCH2)2Fe2(CO)6NCH2CH2N (μ-SCH2)2]Fe2(CO)6 (9) are described. These two complexes are readily prepared in a SN2 manner between double lithium anion and bis(chloromethyl) amine derivatives. The structures of 8 and 9 were characterized by IR, 1H, 13C NMR, MS and HRMS spectra and further determined by X-ray analyses. Protonation of complex 8 gave the mono N-protonated product, while for 9 the protonation occurred in both of the N atoms. The redox properties were evaluated by cyclic voltammograms. It was shown that these two complexes can catalyze electrochemical reduction of proton to molecular hydrogen.  相似文献   

5.
The reaction of [Cu(CH3CN)4]BF4, 6-(4-methoxyl)phenyl-2,2′-bipyridine (designated as MeO-CNN), and/or tricyclohexylphosphine (PCy3) and diimine ligands derived from 4,4′-bipyridine gave four mono- and binuclear copper(I) complexes, [Cu(MeO-CNN)2]BF4 (1), [Cu2(MeO-CNN)2(PCy3)2(4,4′-bipy)](BF4)2 · 1.5CH2Cl2 (2) (bipy = bipyridine), [Cu2(MeO-CNN)2(PCy3)2(bpete)](BF4)2 · 4CH2Cl2 (3) (bpete = trans-1,2-bis(4-pyridyl)ethene) and [Cu2(MeO-CNN)2(PCy3)2(4,4′-azpy)] (BF4)2 · 1.5CH2Cl2 (4) (azpy = azobispyridine). Crystallographic studies of complexes 1-4 show that each copper(I) center adopts a pseudo-tetrahedral coordination geometry. Complexes 2-4 consists of -Cu(MeO-CNN)(PCy3) units which are linked through 4,4′-bipy, bpete and 4,4′-azpy, respectively. The UV-Vis spectra of these four complexes all exhibit intense high-energy absorptions at λmax < 340 nm and broad visible bands in a range of 430-550 nm, ascribed to intraligand (IL π → π) transitions and metal-to-ligand charge-transfer (MLCT) transitions, respectively. The density functional theory calculation was used to interpret the absorption spectrum of 1, which further supports the assignment of MLCT character. The binuclear complexes 2 and 3 both display red solid-state emissions centred at 620 and 660 nm from metal-to-ligand charge-transfer excited state, respectively. Interestingly, the electron paramagnetic resonance (EPR) spectral measurements confirm copper(I) complexes oxidized to corresponding copper(II)-halide product upon excitation at 355 nm in dichloromethane solution.  相似文献   

6.
Interaction of cadmium(II) or zinc(II) acetate with 1,2-bis(4-pyridyl)ethane (bpe) in the presence of dioxime(1,2-cyclohexanedionedioxime = NioxH2 or diphenylglyoxime = dpgH2) resulted in three complexes with the compositions [Cd2(CH3COO)4(NioxH2)2(bpe)(H2O)2] (1), [Cd(CH3COO)2(bpe)(H2O)]n (2) and [Zn(CH3COO)2(NioxH2)(bpe)(H2O)]n (3), which were characterized by single-crystal X-ray diffraction, elemental analysis, IR, and luminescence spectroscopy. Dioxime-containing binuclear molecule 1 and 1D linear polymer 3 possess moderate luminescence properties, while the dioxime-free 1D polymer 2 demonstrates strong blue luminescence.  相似文献   

7.
Reaction of nickel (II) perchlorate with the ligand N,N′-bis-(3,5-dipiperidin-1-yl-[2,4,6]triazin-1-yl)-pyridin-2-ylmethyl-ethane-1,2-diamine yields an octahedral Ni(II) high-spin complex 1 ([C40H56N14Ni(H2O)(CH3OH)](ClO4)2(CH3OH)2) with moderate zero-field splitting (ZFS) axial distortion parameter D/kB = 5.37 K. The ligand contributes a N4 donor set; the remaining two coordinating positions are occupied by coordinating solvents molecules. Exchange of the coordinating solvents molecules in complex 1 to thiocyanate moieties leads to formation of complex 2 ([C40H56N14Ni(NCS)2](CHCl)3) with an extended parameter D/kB = 8.80 K. The analysis of the structural and magnetic properties of complexes 1 and 2 led to the design of dinuclear complex 3 ([C40H56N14NiN3]2(ClO4)2(CH3OH)2), where two azido groups were utilized as bridging ligands. The double azido bridges in complex 3 cross each other to form a rarely observed non-coplanar (N3)2 structure. The magnetic behavior of complex 3 reveals ferromagnetic coupling interactions characterized by J/kB = 23.25 K, D1/kB = 7.90 K, D2/kB = 0.54 K.  相似文献   

8.
A series of osmium(VI) nitrido complexes containing pyridine-carboxylato ligands OsVI(N)(L)2X (L = pyridine-2carboxylate (1), 2-quinaldinate (2) and X = Cl (a), Br (1b and 2c) or CH3O (2b)) and [OsVI(N)(L)X3] (L = pyridine-2,6-dicarboxylate (3) and X = Cl (a) or Br (b)) have been synthesised. Complexes 1 and 2 are electrophilic and react readily with various nucleophiles such as phosphine, sulfide and azide. Reaction of OsVI(N)(L)2X (1 and 2) with triphenylphosphine produces the osmium(IV) phosphiniminato complexes OsVI(NPPh3)(L)2X (4 and 5). The kinetics of nitrogen atom transfer from the complexes OsVI(N)(L)2Br (2c) (L = 2-quinaldinate) with triphenylphosphine have been studied in CH3CN at 25.0 °C by stopped-flow spectrophotometric method. The following rate law is obtained: −d[Os(VI)]/dt = k2[Os(VI)][PPh3]. OsVI(N)(L)2Cl (L = 2-quinaldinate) (2a) reacts also with [PPN](N3) to give an osmium(III) dichloro complex, trans-[PPN][OsIII(L)2Cl2] (6). Reaction of OsVI(N)(L)2Cl (L = 2-quinaldinate) (2a) with lithium sulfide produces an osmium(II) thionitrosyl complex OsII(NS)(L)2Cl (7). These complexes have been structurally characterised by X-ray crystallography.  相似文献   

9.
Four cadmium(II) complexes of the semirigid tridentate ligand 8-[(pyridin-4-yl)methylthio] quinoline (TQMP4, L), namely, [CdL2](ClO4)2 (1), [Cd(L)Br2] (2), [Cd2(L)2(NO3)4] (3), and [Cd2(L)2I4] (4), have been prepared by the methods of layering and the diffusing of diethyl ether. The structures of the complexes have been identified by elemental analysis (EA), infrared spectra (IR) and single-crystal diffraction. The different coordination modes of the ligands and counter anions result in a 2D (4, 4) net structure in complex 1, a 1D polymer chain in complex 2, and 0D binuclear rings in complexes 3 and 4. Their antibacterial and antifungal activities were also tested.  相似文献   

10.
11.
12.
《Inorganica chimica acta》1988,149(2):259-264
The bis(N-alkylsalicylaldiminato)nickel(II) complexes Ni(R-sal)2 with R = CH(CH2OH)CH(OH)Ph (I), R = CH(CH3)CH(OH)Ph (II) and R = CH2CH2Ph (III; Ph = phenyl) were prepared and characterized. In the solid state I and II are paramagnetic (μ = 3.2 and 3.3 BM at 20 °C, respectively), whereas III is diamagnetic. It follows from the UV-Vis spectra that in acetone solution I is six-coordinate octahedral and III is four-coordinate planar, the spectrum of II showing characteristics of both modes of coordination. Vis spectrophotometry and stopped-flow spectrophotometry were applied to study the kinetics of ligand substitution in I–III by H2salen (= N,N′-disalicylidene-ethylenediamine) in the solvent acetone at different temperatures. The kinetics follow a second-order rate law, rate = k[H2-salen] [complex]. At 20 °C the sequence of rate constants is k(III):k(II):k(I) = 11 850:40.6:1. The activation parameters are ΔH(I) = 112, ΔH(II) = 40.7, ΔH(III) = 35.7 kJ mol−1 and ΔS(I) = 92, ΔS(II) = −103, ΔS(III) = −89 J K−1 mol−1. The enormous difference in rate between complexes I, II and III, which is less pronounced in methanol, is attributed to the existence of a fast equilibrium planar ⇌ octahedral, which is established in the case of I and II by intramolecular octahedral coordination through the hydroxyl groups present in the organic group R. An A-mechanism is suggested to control the substitution in the sense that the entering ligand attacks the four-coordinate planar complex, the octahedral complex being kinetically inert.  相似文献   

13.
Two new μ-oxamido-bridged binuclear copper(II) complexes with formulae of [Cu2(heae)(pic)2] (1) and [Cu2(heae)(Me2phen)2](ClO4)2 · H2O (2), where heae and pic stand for the anion of N,N′-bis(N-hydroxyethylaminoethyl)oxamide and 2,4,6-trinitrophenol, respectively, and Me2phen represents 2,9-dimethyl-1,10-phenanthroline; have been synthesized and characterized by elemental analyses, molar conductivity measurements, IR and electronic spectra studies. The crystal structures of the two binuclear copper(II) complexes have been determined by X-ray single-crystal diffraction. In both the two binuclear complexes the central two copper(II) atoms are bridged by trans-heae. In complex 1 the coordination environment around each copper(II) atom can be described as a distorted octahedral geometry, while in complex 2 each copper(II) atom displays a square-pyramid stereochemistry. Hydrogen bonding and π-π stacking interactions link the binuclear copper(II) complex 1 or 2 into a 3D infinite network. The cytotoxicities of the two binuclear copper(II) complexes were tested by Sulforhodamine B (SRB) assays against human hepatocellular carcinoma cell SMMC-7721 and human lung adenocarcinoma cell A549. Both of the two binuclear copper(II) complexes exhibit potent cytotoxic effects against SMMC-7721 and A549 cell lines. The interactions of the two binuclear complexes with herring sperm DNA (HS-DNA) are investigated by using absorption and emission spectra and electrochemical techniques and viscometry. The results suggest that both the two binuclear copper(II) complexes interact with HS-DNA in the mode of intercalation with the intrinsic binding constants of 1.73 × 105 M−1 (1) and 1.92 × 106 M−1 (2). The influence of structural variation of the terminal ligands in the binuclear complexes on DNA-binding properties is preliminarily discussed.  相似文献   

14.
《Inorganica chimica acta》2006,359(9):2812-2818
Alkynylgold(I) complexes incorporating a chiral binaphthyl group have been prepared. Bis(alkyne) reagents [rac-1,1′-C20H12-2,2′-(OCH2CCH)2] (1) and [rac-1,1′-C20H12-2,2′-(OC(O)CH2CCH)2] (2), react with [AuCl(SMe2)] and base to give insoluble oligomeric alkynylgold(I) complexes [rac-1,1′-C20H12-2,2′-(OCH2CCAu)2]n (3) and [rac-1,1′-C20H12-2,2′-(OC(O)CH2CCAu)2]n (4), which react with phosphine or diphosphine ligands to give soluble complexes [rac-1,1′-C20H12-2,2′-(OCH2CCAuPR3)2] (5), R = Ph or Cy, [rac-1,1′-C20H12-2,2′-(OCH2CCAu)2(Ph2P(CH2)nPPh2)] (6), or [rac-1,1′-C20H12-2,2′-(OC(O)CH2CCAu)2(Ph2P(CH2)nPPh2)] (7), with n = 3–5. Several of the complexes 6 and 7 are shown to exist as mixtures of isomeric forms in solution.  相似文献   

15.
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   

16.
The reaction of the rhenium(V) nitrido complex [Re(N)Cl2(PPh3)2] with the tripodal ligand N(CH2CH2PPh2)3 (NP3) in THF gave [Re(N)Cl22-P,P-NP3)] (1) in which NP3 acts as a tridentate ligand using the nitrogen and two phosphorus donors for coordination. Refluxing 1 in a polar solvent such as ethanol produced [(η4-NP3)Re(N)Cl]Cl (2) in which NP3 acts as a tetradentate ligand. Treatment of complex [Re(O)Cl3(AsPh3)2] containing the [ReO]3+ core with NP3 in THF yielded [ReCl33-N,P,P-(N{CH2CH2Ph2}2{CH2CH2P(O)Ph2})}] (3). Complexes 1 and 3 have been characterized by single-crystal X-ray analyses.  相似文献   

17.
The reactions of the dianionic [(pyrrole-2-CHN)2R]2? ligands [(N′2N2)2?] (R = (R)(S)-1,2-cyclohexane or 1,2-ethane) with Zn(II) yield neutral dimeric [Zn2(N′2N2)2] complexes. The dimeric nature of the complexes was established by field-desorption mass spectrometry. 1H NMR studies show that these complexes have dimeric structures in solution in which the (N′2N2)2? ligands act as di-bidentates.The metal centres have tetrahedral geometries and bot have Δ or Λ configurations. The complex with the (R)(S)-1,2-cyclohexanediyl bridges has a rigid structure in solution. Neither intermolecular nor intramolecular exchange processes are observed The 1H NMR spectrum of the complex with the 1,2-ethanediyl bridging groups shows that at 213 K in CDCl3 a fast conformational movement is already taking place between two identical structures of the complex. It is not possible to determine whether in this complex intermolecular exchange processes are also taking place.The reactions of the anionic [pyrrole-2-CHNR′]? ligands [(N′N)?] (R′ = t-Bu, i-Pr, (S)-CHMePh or 2,6-xylyl) with Zn(II) yield the neutral Zn(N′N)2 complexes. These complexes were synthesized to study the coordination properties of the [pyrrole-2-CHNR′]? moieties with Zn(II). A 1H NMR study established that the zinc centres in the complexes containing the prochiral i-Pr or chiral (S)-CHMePh substituents have tetrahedral geometries with Δ or Λ configurations in CDCl3 at 213 K. These complexes undergo an intramolecular exchange process at higher temperatures (above 260 K when R′ = i-Pr) which involves inversion of the configuration of the zinc centre. A mechanism for this exchange process is proposed.  相似文献   

18.
Two new ion-pair complexes, [FBrBzPyN(CH3)2]2[Ni(mnt)2] (1) and [FBrBzPyN(CH3)2][Ni(mnt)2] (2) (mnt2− = maleonitriledithiolate, [FBrBzPyN(CH3)2]+ = [1-(4′-fluoro-2′-bromobenzyl)-4-dimethylaminopyridinium]) have been prepared and characterized by elemental analyses, UV, IR, single crystal X-ray diffraction and magnetic susceptibility. The cations (D) and the anions (A) in 1 stack into a 1D alternating column (i.e., of type ?DDADDADD?) via short S?Br, N?F, C?N interactions, and C-H?Br hydrogen bonds. The cation-cation π?π stacking interactions within the columns give further rise to a 2D network structure. Compound 2 forms a 3D structure in which the Ni(III) ions stack into a uniform 1D zigzag magnetic chain through Ni?S, Ni?Ni, or π?π interactions with a Ni?Ni distance of 4.024 Å. Magnetic susceptibility measurements in the temperature range 2-300 K show that 1 is expected to be diamagnetic, and 2 exhibits an interesting spin-gap transition (Δ/kb = 460.6 K) around 155 K.  相似文献   

19.
In this paper, two new dipicolinate complexes, Ln2(dipic)3(H2O)3 (1) with Ln=La, Ce, Pr, Nd, Sm and Ce3(dipic)5(H2O)2 (2), are described. Hydrothermal synthesis, crystal structure and thermal behaviour of both compounds are described, as well as the magnetic behaviour of the trinuclear complex (2). The structures consist of LaO7N2, LaO7N (1) and CeO7N, CeO6N3 (2) polyhedra linked to form three-dimensional networks. The magnetic study of 2 confirms that it corresponds to a Ce(III)-Ce(IV) molecular compound and that the magnetic interaction is certainly antiferromagnetic. According to the thermogravimetric analysis, thermal decomposition of compounds 1 starts at about 100-130 °C, when 2 is thermally stable up to 250 °C.  相似文献   

20.
Three new supramolecular coordination complexes [Zn(Hdmpz)2(O2C(CH2)2CO2)]n (1), Ni3(Hdmpz)4(HOOC(CH2)2CO2)2(O2C(CH2)2CO2)2(CH3OH)2 (2) and Co3(Hdmpz)2(HOOC(CH2)3CO2)2(O2C(CH2)3CO2)2(CH3OH)4 (3) (Hdmpz = 3,5-dimethylpyrazol) have been synthesized and characterized by elemental analyses, IR spectra and single crystal X-ray diffraction analysis. Complex 1 is a polymer with the ZnO4N2 core that is interconnected by bridging succinate moieties into a 1D chain structure. Complexes 2 and 3 are discrete structures, both of them have two types of bridging-coordinated modes of carboxylate ligands (μ322, μ211). And there are rich intra- or intermolecular hydrogen bonds in the crystals of 1-3, thereby forming a set of supramolecular frameworks. In addition, the thermal behaviors of 1-3 were also investigated.  相似文献   

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