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1.
Three coordination complexes of formula [Ni(L1)2(H2O)4].4H2O (1), [Mn(L2)2(H2O)4] (2) and [Mn(L2)2(H2O)2]n (3) [L1H = 6-methylpyridine-3-carboxylic acid, L2H = 3-(3-pyridyl)acrylic acid] have been synthesized and structurally characterized by X-ray single crystal analysis. A 3D network is achieved through H-bonding in 1 and 2, while crystal packing of complex 3 shows a 3D supramolecular coordination polymer. Thermal properties have been investigated by thermogravimetric analysis. Luminescence study features the presence of LMCT and metal purterbed ligand centered emission bands.  相似文献   

2.
To investigate the influence of temperature and the ratios of solvents on the design and synthesis of metal-organic frameworks (MOFs), we have synthesized and structurally characterized a series of supramolecular assemblies based on different amino acid derivatives and nitrogen-containing heterocyclic ligands, namely [Mn(phen)2(phth)(H2O)]·4H2O (1), [Mn(phen)2(HL1)2]·3.5H2O (2), [Zn(bpp)2(L-Me)2] (3), and [Zn(bpp)(L-Me)2] (4) (H2phth = phthalic acid, H2L1 = phthalyl-l-valine, H2L = (+)-N-tosyl-l-glutamic acid, phen = 1,10-phenanthroline, bpp = 1,3-bis(4-pyridyl)propane, and L-Me = C12H13NO6S-CH3). Compounds 1 and 2, which are assembled through noncovalent interactions, were obtained by controlling the temperature. In 1, π-π stacking and hydrogen-bonding interactions lead to stacking in a 3D supramolecular network, while in 2, π-π stacking interactions form 1D chains that extend along the c-axis. Depending on the solvents employed, compounds 3 and 4 could be generated, with a 1D bpp-connected Zn-bpp-Zn double chain that is further hydrogen-bonded into a 2D network that extends parallel to the ac plane in 3, and a single chain in 4.  相似文献   

3.
Synthesis and crystal structure of two coordination polymers of composition [MnII(H2bpbn)1.5][ClO4]2 · 2MeOH · 2H2O (1) and [CoII(H2bpbn)(H2O)2]Cl2 · H2O (2) [H2bpbn = N,N′-bis(2-pyridinecarboxamido)-1,4-butane], formed from the reaction between [Mn(H2O)6][ClO4]2/CoCl2 · 4H2O with H2bpbn in MeCN, are described. In 1 each MnII ion is surrounded by three pyridine amide units, providing three pyridine nitrogen and three amide oxygen donors. Each MnII center in 1 has distorted MnN3O3 coordination. In 2 each CoII ion is coordinated by two pyridine amide moieties in the equatorial plane and two water molecules provide coordination in the axial positions. Thus, the metal center in 2 has trans-octahedral geometry. In both 1 and 2, the existence of 1D zigzag network structure has been revealed. Owing to π-π stacking of pyridine rings from adjacent layers 1 forms 2D network; 2 forms 2D and 3D network assemblies via N-H?Cl and O-H?Cl secondary interactions. Both the metal centers are high-spin.  相似文献   

4.
Two new Mn(II) coordination polymers with bis(5-tetrazolyl)methane (H2btm), [Mn(btm)(phen)(H2O)] · H2O (1) and [Mn(btm)(2,2′-bpy)] · 1.5H2O (2), have been synthesized and their structures determined by X-ray diffraction. In complex 1, the btm ligands assume the μ2-1,1′:4 coordination mode and interlink Mn(II) ions into infinite one-dimensional chains. The chains are assembled into a three-dimensional architecture via hydrogen bonds and π-π interactions. For 2, Mn(II) ions are connected by btm ligands in the μ3-1,1′:2:3′ mode to produce two-dimensional (6,3) coordination network. Magnetic investigations revealed that interactions through the btm bridges in both 1 and 2 are antiferromagnetic.  相似文献   

5.
Complexes [Cu(HSas)(H2O)] · 2H2O (H3Sas = N-(2-hydroxybenzyl)-l-aspartic acid) (1), [Cu(HMeSglu)(H2O)] · 2H2O (H3MeSglu = (N-(2-hydroxy-5-methylbenzyl)-l-glutamic acid) (2), [Cu2(Smet)2] (H2Smet = (N-(2-hydroxybenzyl)-l-methionine) (3), [Ni(HSas)(H2O)] (4), [Ni2(Smet)2(H2O)2] (5), and [Ni(HSapg)2] (H2Sapg = (N-(2-hydroxybenzyl)-l-aspargine) (6) have been synthesized and characterized by chemical and spectroscopic methods. Structural determination by single crystal X-ray diffraction studies revealed 1D coordination polymeric structures in 2 and 4, and hydrogen-bonded network structure in 5 and 6. In contrast to previously reported coordination compounds with similar ligands, the phenol remains protonated and bonded to the metal ions in 2 and 4, and also probably in 1. However, the phenolic group is non-bonded in 6.  相似文献   

6.
Two novel Cd(II) coordination polymers, [(CH3)2NH2]2[Cd(cma)2](H2O) (1) and [Cd3(bcma)2(H2O)](H2O) (2) (H2cma = N-(carboxymethyl)-anthranilic acid, H3bcma = N,N′-bis-(carboxymethyl)-anthranilic acid), have been synthesized under hydrothermal conditions and characterized by X-ray single crystal analysis, IR spectra and TGA. Compound 1 possesses 1D double-stranded chain, which further packs into square channels. Compound 2 consists of a novel 3D framework, which not only possesses unique meniscus-like channels but also contains infinite helical chains. Compound 2 is the first example of Cd(II)-aminopolycarboxylate coordination polymers containing three crystallographically independent Cd(II) centres, in which Cd(1), Cd(2), and Cd(3) present distorted pentagonal bipyramidal, tetragonal antiprismatic, and trigonal bipyramidal coordination geometry, respectively. Both compounds display intense room temperature photoluminescence in the solid state.  相似文献   

7.
Two new nickel(II) complexes with the composition [Ni(L+H)(CH3CN)2](ClO4)3 (1) and [Ni(L)(tp)]·6H2O (2), (L = 3,10-bis{3-(1-imidazolyl)propyl}-1,3,5,8,10,12-hexaazacyclotetradecane, tp = terephthalate) have been synthesized and structurally characterized by a combination of analytical, spectroscopic and X-ray diffraction methods. The structure of 1 consists of monomeric cations of the formula [Ni(L+H)(CH3CN)2]3+ and perchlorate ions. The nickel(II) ion is six-coordinate with bonds to the four nitrogen atoms of the macrocycle and two nitrogen atoms of the axial acetonitrile ligands. One of the protonated imidazole pendants of the macrocycle is hydrogen bonded to the imidazole group of the neighboring nickel(II) macrocycle, forming an undulated 1D supramolecule. Then, the two 1D supramolecular chains are further interconnected by C-H···π interactions between the methyl group of the acetonitrile ligand and one of the imidazole groups to form a 2D double stranded supramolecular polymer. In the structure of 2, the 1D coordination polymer is formed with nickel(II) macrocycles and bridging terephthalate ions, where each 1D chain is interconnected with π-π interactions of pendant imidazole moieties of the macrocycles, resulting in the formation of a 2D supramolecule.  相似文献   

8.
The reaction of Zn(ClO4)2 · 6H2O and Cu(ClO4)2 · 6H2O with H3Sas (H3Sas = N-(2-hydroxybenzyl)-L-aspartic acid in water afforded the complexes [Zn6(Sas)4(H2O)8]·5H2O (1) and [Cu(HSas)(H2O)] (2), respectively, which were characterized by infrared spectroscopy, elemental analysis, thermogravimetry and single-crystal X-ray crystallography. In 1, the pentanuclear clusters formed by four H3Sas ligands and five Zn(II) metal ions are bridged by the “[Zn(H2O)4]2+” cations to form 1D polymeric chains. While in 2, the mononuclear [Cu(HSas)(H2O)] repeating units form a 1D zigzag chain and further extended by strong intermolecular hydrogen bonds to form a 2D sheet. The different coordination geometries of Cu(II) and Zn(II) show significant influence on the polymeric structures.  相似文献   

9.
Three novel coordination complexes [Mn(tpha)(phen)]n (1); [Mn(na)2(H2O)2]n (2); {[Mn(phen)2(OH)Cl] · Cl · (OH) · (C9H11NO2) · 2H2O} (3) have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction (H2tpha = terephthalic acid, Hna = nicotinic acid, phen = 1,10-phenanthroline). The tpha groups in complex 1 bridge the Mn(II) ions to an infinite 3D framework. Complex 2 exhibits a 2D network structure in which the Mn(II) ions are linked by nicotinic groups. Complex 3 is connected to a 2D coordination supramolecule by hydrogen bonds. The results of surface photovoltage spectra (SPS) of complexes 1-3 indicate that they all exhibit positive surface photovoltage (SPV) responses in the range of 300-800 nm. However, the intensity, position and numbers of SPV responses are obviously different. The distinctions can be mainly attributed to their structures, valences and coordination environments of the manganese ions in the three complexes. Moreover the external field induced surface photovoltage spectra (FISPS) of the three complexes have been measured.  相似文献   

10.
Based on self-assembly of the dissymmetrical mononuclear entity CuL(CH3OH) [H2L = (E)-N1-(2-((2-aminocyclohexydiimino)(phenyl)methyl)-4-chlorophenyl)-N2-(2-benzyl-4-chlorophenyl)oxalamide] with Mn(II), two trinuclear complexes were prepared. They are of the formula [(LCuN3)2Mn(CH3OH)2] · 2CH3OH · 2H2O (1) and [(LCuSCN)2Mn(H2O)2] · 4CH3OH (2). Their magnetic properties were studied by susceptibility versus temperature measurement, the best fitting of the experimental data led to J = −14.40 cm−1 for 1 and J = −15.48 cm−1 for 2. Hydrogen bonds help complex 1 to produce a novel S type one-dimensional chain-like supramolecular structure. In complex 2, Cl?Cl interaction also results in the formation of a one-dimensional structure.  相似文献   

11.
2,6-Dimethyl-4-phenylpyridine-3,5-dicarboxylic acid (H2mppdc, H2L) is firstly employed in coordination chemistry. Two metal-organic coordination polymers with a general formula of M2L2(4,4′-bpy)x(H2O)4−2x (M = Zn or Co, x = 1 or 2) are assembled from H2L, 4,4′-bipyridine, zinc and cobalt salt under hydrothermal conditions, and characterized by single-crystal X-ray diffraction analyses. Of the crystal structures of title compounds, L ligands, limited in the environment from 4,4′-bipyridine, array in head-to-head and head-to-tail modes which are corresponding to the 1D (1) and 3D (2) polymeric structures, respectively. Interesting disorders occur in the crystal lattice of compound 1. And compound 2 has a 3D 42 · 610 · 83 topology. Solid-state H2L and 1 have expected photoluminescence at room temperature.  相似文献   

12.
The metal complexation properties of a functionalized N3O2 donor ligand H2L2, where H2L2 stands for 2,6-diacetyl-4-carboxymethyl-pyridine bis(benzoylhydrazone), are investigated by structural and spectroscopic (IR, ESI-MS and EPR) characterization of its Mn(II) and Co(II) complexes. The ligand H2L2 is observed to react essentially in the same fashion as its unmodified parent H2L1 producing mixed-ligand [M(H2L2)(Cl2)] complexes (M = MnII (1), CoII (3)) upon treatment with MCl2. Complexes [M(HL2)(H2O)(EtOH)]BPh4 (M = Mn 2, M = Co 4), incorporating the supporting ligand in the partially deprotonated form (HL2), are formed by salt elimination of the [M(H2L2)(Cl2)] compounds with NaBPh4. Compounds 2 and 4 are isostructural featuring distorted pentagonal-bipyramidal coordinated MnII and CoII ions, with the H2O and EtOH ligands bound in axial positions. Intermolecular hydrogen bonding interactions of the type M-OH2?O-M involving the H2O ligands and the carbonyl functions of the supporting ligand assembles the complexes into dimers. Temperature-dependent magnetic susceptibility measurements (2-300 K) show a substantially paramagnetic Curie behavior for the Mn2+ compound (2) influenced by zero-field splitting and significant orbital angular momentum contribution for 4 (high-spin CoII). The exchange coupling across the MnII-OH2?O-MnII bridges in 2 was found to be less than 0.1 cm−1, suggesting that no significant intradimer exchange coupling occurs via this path.  相似文献   

13.
Assembly of N,N′-bis(4-picolinoyl)hydrazine (H2L) with cadmium nitrate in the presence of dicyanamide anion (dca) affords a new coordination polymer {[Cd(HL)(dca)] · (H2O)0.5}n (1), in which the [Cd(HL)]n layers are extended by dca bridges to result in a three-dimensional (3-D) coordination framework. The network structure of 1 has unusual (3,5)-connectivity and represents a new type of (4·62)(4·66·83) topology. Two such identical and complementary networks are entangled to generate a twofold parallel interpenetrating supramolecular lattice.  相似文献   

14.
Ten transition metal coordination complexes [Cu2(phen)(p-tpha)(μ-O)]n1, [Cu(m-tpha)(imH)2]n2, [Ni(5-Haipa)2(H2O)2]n3, [Ni(phen)2(H2O)2]·btc·[Ni(H2O)6]0.5·9H2O 4, [Co(2,5-pdc)(H2O)2]n·nH2O 5, [Co2(2,5-pdc)2(H2O)6]n·2nH2O 6, [Fe(2,5-Hpdc)2(H2O)2]·H2O 7, [Co(C6H4NO2)3]·H2O 8, [Fe22-btec)(μ2-H2btec)(bipy)2(H2O)2]n9, [Mn(phen)(2,5-pdc)(H2O)2]·H2O 10 (H4btec = 1,2,4,5-benzenetetracarboxylic acid, phen = 1,10-phenanthroline, 2,5-H2pdc = 2,5-pyridine-dicarboxylic acid, p-tpha = p-phthalic acid, m-tpha = m-phthalic acid, bipy = 2,2′-bipyridine, 5-H2aipa = 5-aminoisophthalic acid, imH = imidazole, H3btc = 1,3,5-benzenetricarboxylic acid) were synthesized through hydrothermal method. They were characterized by UV-Vis absorption spectra, single-crystal X-ray diffraction and surface photovoltage spectra (SPS). Structural analysis indicated that the complexes 1, 2, 3, 5, 6 and 9 were linked into infinite structures bridged by organic acid ligands. The other four complexes were molecular complexes and further connected to 2D or 3D structures by the hydrogen bonds. The SPS of complexes 1-10 indicate that there are positive response bands in the range of 300-800 nm showing different levels of photo-electric conversion properties. The intensity, position, shape and the number of the response bands in SPS are obviously different since the structure, species, valence, dn electrons configuration and coordinated environment of the center metals are different. There are good relationships between SPS and UV-Vis spectra.  相似文献   

15.
Reaction of the N-tosyl-ethylenediamine and salicylaldehyde forms a new sulfonamide Schiff base N-[2-(2-hydroxybenzylideneamino)ethyl]-4-methyl-benzene-sulfonamide (H2L). Three novel complexes constructed from H2L, namely, [M(HL)2] · xH2O (M = Cu, x = 0 for 1, M = Ni, x = 0 for 2 and M = Zn, x = 1 for 3) have been prepared and characterized via X-ray single-crystal diffraction, elemental analysis, X-ray powder diffraction (XRPD), FT-IR, UV-Vis, TGA and photoluminescence measurements. Complex hydrogen bonds, C-H···π and π-π stacking interactions lead 1-3 to present 1-D, 2-D and 3-D supramolecular architectures, respectively.  相似文献   

16.
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   

17.
Four new zinc(II) cyclams of the composition {Zn(L)(tp2−) · H2O}n (1), {Zn(L)(H2bta2−) · 2H2O}n (2), [Zn2(L)2(ox2−)] 2ClO4 · 2DMF (3), and Zn(L)(H2btc)2 · 2DMF (4), where L = cyclam, tp2− = 1,4-benzenedicarboxylate ion, H2bta2− = 1,2,4,5-benzenetetracarboxylate ion, ox2− = oxalate ion, DMF = N,N-dimethylformamide, and H2btc = 1,3,5-benzenetricarboxylate ion, have been synthesized and structurally characterized by a combination of analytical, spectroscopic and crystallographic methods. The carboxylato ligands in the complexes 1-4 show strong coordination tendencies toward zinc(II) cyclams with hydrogen bonding interactions between the pre-organized N-H groups of the macrocycle and oxygen atoms of the carboxylato ligands. The macrocycles in 1, 2, and 4 adopt trans-III configurations with the appropriate R,R,S,S arrangement of the four chiral nitrogen centers, respectively. However, the complex 3 shows an unusual cis V conformation with the R,R,R,R nitrogen configuration. The finding of strong interactions between the carboxylato ligands and the zinc(II) ions may provide additional knowledge for the improved design of receptor-targeted zinc(II) cyclams in anti-HIV agents.  相似文献   

18.
Manganese(II) complexes, Mn2L13(ClO4)4, MnL1(H2O)2(ClO4)2, MnL2(H2O)2(ClO4)2, and {(μ-Cl)MnL2(PF6)}2 based on N,N′-bis(2-pyridinylmethylene) ethanediamine (L1) and N,N′-bis(2-pyridinylmethylene) propanediamine (L2) ligands have been prepared and characterized. The single crystal X-ray diffraction analysis of Mn2L23(ClO4)4 shows that each of the two Mn(II) ion centers with a Mn-Mn distance of 7.15 Å are coordinated by one ligand while a common third ligand bridges the metal centers. Solid-state magnetic susceptibility measurements as well as DFT calculations confirm that each of the manganese centers is high-spin S = 5/2. The electronic structure obtained shows no orbital overlap between the Mn(II) centers indicating that the observed weak antiferromagentism is a result of through space interactions between the two Mn(II) centers. Under different reaction conditions, L1 and Mn(II) yielded a one-dimensional polymer, MnL1(H2O)2(ClO4)2. Ligand L2 when reacted with manganese(II) perchlorate gives contrarily to L1 mononuclear MnL2(H2O)2(ClO4)2 complex. The analysis of the structural properties of the MnL2(H2O)2(ClO4)2 lead to the design of dinuclear complex {(μ-Cl)MnL2(PF6)} where two chlorine atoms were utilized as bridging moieties. This complex has a rhomboidal Mn2Cl2 core with a Mn-Mn distance of 3.726 Å. At room temperature {(μ-Cl)MnL2(PF6)} is ferromagnetic with observed μeff = 4.04 μB per Mn(II) ion. With cooling, μeff grows reaching 4.81 μB per Mn(II) ion at 8 K, and then undergoes ferromagnetic-to-antiferromagnetic phase transition.  相似文献   

19.
A chiral Schiff base N-(S)-2-(6-methoxylnaphthyl)-propanoyl-N′-(2-hydroxylbenzylidene)hydrazine (H2L) has been synthesized. Reaction of H2L with Cu(OAc)2 · H2O led to the formation of a metal complex {[CuL] · H2O · 2DMF} (1). In complex 1, the potential dinegative tridentate L2− ligand acting as tetradentate bridging ligand coordinate to two metal ions so as to form a novel infinite metal-organic coordination chain structure. The enantiomerically pure ligand H2L presents two different sets of signals in the 1H NMR spectrum either in chloroform solution or in dimethylsulfoxide solution, showing the presence of both (E) and (Z) isomers. The X-ray structural investigations of H2L revealed that it is the fully extended E-configuration in the solid state.  相似文献   

20.
Two new coordination polymers [Cd(dps)2Cl2] (1) and [Co(dps)2(H2O)2]·(abs)2(H2O)2 (2) (dps = 4, 4′-dipyridylsulfide, Habs = 4-amino benzenesulfonic acid) have been synthesized under similar conditions and characterized by elemental analysis, fluorescence spectra and single crystal X-ray diffraction. Compound 1 displays a dps-bridged 2D puckered, grid-like layer, which is further linked by C-H?Cl hydrogen bonds to form a 3D supramolecular architecture. Compound 2 shows a dps-bridged double-stranded chain structure, which is extended by N-H?O and O-H?O hydrogen bonds generating a 3D network. Solid-state fluorescence results reveal that both complexes can emit strong emission bands, at 467 nm and 518 nm for 1 and 344 nm for 2, respectively. Magnetic measurements show that there are weak antiferromagnetic interactions between the adjacent Co(II) ions in 2.  相似文献   

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