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1.
The nickel(II) complexes of the compositions [Ni(hmidtc)(bpy)2]ClO4 (I), [Ni(hmidtc)(phen)2]ClO4 (II), [Ni(hmidtc)(phen)2]SCN (III), [Ni(hmidtc)(phen)2]PF6 (IV), [Ni(hmidtc)(phen)2]BPh4 (V), [Ni(hmidtc)(phen)2]AcO·2H2O (VI) and [Ni(hmidtc)(phen)2]Br·H2O (VII), involving a combination of one hexamethyleneimine-dithiocarbamate anion (hmidtc) and two bidentate N,N-donor ligands (2,2′-bipyridine (bpy) for I or 1,10-phenanthroline (phen) for II-VII), have been prepared. The compounds were characterized by elemental analysis, molar conductivity measurements, UV-Vis and IR spectroscopy, magnetochemical measurements and thermal analysis. A single-crystal X-ray analysis of the complex I revealed a distorted octahedral geometry with the nickel(II) ion coordinated by four nitrogen atoms (from two bidentate-coordinated bpy molecules) and two sulfur atoms (from one bidentate-coordinated hmidtc anion), together giving an NiN4S2 donor set. 相似文献
2.
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, [Fe2(μ2-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
3.
The P,P′diphenylmethylenediphosphinic acid (H2pcp) reacts with Co(ClO4)2 · 6H2O and 4,4′-bipyridine to give a mixture of two polymeric isomers of formula [Co(pcp)(bipy)0.5(H2O)2], {red (1) and pink (2)} and the new violet hybrid [Co(Hpcp)2] (3). The pure red and violet species have been obtained by the reaction of H2pcp with Co(CH3COO)2 · 4H2O and bipy or with Co(ClO4)2 · 6H2O, respectively. The analogous reaction of Ni(CH3COO)2 · 4H2O or Ni(ClO4)2 · 6H2O with H2pcp and bipy affords only the [Ni(pcp)(bipy)0.5(H2O)2] species (4). The two cobalt isomers present different structural arrangements. Whereas the red isomer (1) shows an undulated 2D layered structure, the pink one (2) forms an infinite monodimensional strand. Both the architectures extend to higher dimensions through hydrogen bonding interactions. The nickel derivative is isomorphous with the red cobalt isomer. The violet [Co(Hpcp)2] (3), which is isomorphous with the complexes of the reported series [M(Hpcp)2], M = Ca(II), Mg(II), presents a monodimensional polymeric structure. Compounds 1 and 4 show a very similar thermal behaviour, the two water molecules being lost in the temperature range 25-150 and 160-320 °C, respectively. Temperature dependent X-ray powder diffractometry (TDXD) has been performed on compound 1 in order to follow the structural transformations that occur during the heating process. 相似文献
4.
《Inorganica chimica acta》2004,357(7):1997-2006
Five new lanthanide complexes displaying crotonato bridges have been prepared: [Gd2(crot)6(H2O)4] · 4(bpa) (1); [Ho2(crot)7]n · (Hbpa) (2); [Gd2(crot)6(bipy)2] (3); [Ho2(crot)6(bipy)2] (4) and [Nd2(crot)6(H2O)3]n (5), where bipy=2,2′-bipyridine; bpa=di(2-pyridyl)amine; crot=crotonato. The compounds were characterized by magnetic susceptibility measurements and their crystal structures were determined by single crystal X-ray diffraction. These studies showed complexes 1, 3 and 4 to be dimers while structures 2 and 5 are polymeric in nature. 相似文献
5.
Bellam Sreenivasulu 《Inorganica chimica acta》2009,362(8):2735-281
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 new nickel(II) complexes of the composition [Ni(cyclam)(Hdipic)2] · 2H2O (1) and [Ni(cyclam)(H2O)2][Ni(dipic)2] · 2.5H2O (2) (cyclam = 1,4,8,11-tetraazacyclotetradecane) have been prepared and structurally characterized by a combination of analytical, spectroscopic, thermogravimetric, and crystallographic methods. The structure of 1 shows that the central nickel(II) ion is coordinated axially by two monodentate Hdipic ligands. The discrete neutral complex 1 further extends its structure by hydrogen bonding interactions to form a one-dimensional supramolecule. The structure of 2 consists of two independent nickel(II) centers. Water molecules instead of dipic ligands prefer to coordinate to the Ni1 ion forming a divalent cation [Ni(cyclam)(H2O)2]2+. Two dipic ligands coordinate to the second Ni2 ion forming a divalent anion [Ni(dipic)2]2−. The divalent cations and anions are charge-balanced, resulting in a molecular salt. The divalent cations and anions are interconnected by multiple types of hydrogen bonding interactions. 相似文献
7.
Four palladium(II) and platinum(II) complexes of 2,2′-dipyridylamine (dpya) with saccharinate (sac), cis-[Pd(dpya)(sac)2]·H2O (1), cis-[Pt(dpya)(sac)2]·H2O (2), [Pd(dpya)2](sac)2·2H2O (3) and [Pt(dpya)2](sac)2·2H2O (4), have been synthesized and characterized by elemental analysis, IR, NMR, TG-DTA and X-ray diffraction. In 1 and 2, the metal ions are coordinated by two N-bonded sac ligands, and two nitrogen atoms of dpya, resulting in a neutral square-planar coordination sphere, while in 3 and 4, the metal ions are coordinated by two dpya ligands to generate square-planar cationic species, which are stabilized by two sac counter-ions. The mononuclear species of 1 and 2 interact each other through weak intermolecular N-H?O, C-H?O and π?π interactions to form a three-dimensional network, while the ions of 3 and 4 are connected by N-H?N and OW-H?O hydrogen bonds into one-dimensional chains. On heating at 250 °C, the solid cationic complexes of 3 and 4 convert to corresponding anhydrous neutral complexes of 1 and 2 after elimination of a dpya ligand. In addition, all complexes 1-4 are luminescent at room temperature and their emissions seem to be attributed to the MLCT fluorescence. 相似文献
8.
Four one-dimensional metal-organic polymers derived from diphenic acid (H2dpa) were synthesized in the presence of auxiliary ligands, [Cu(dpa)CH3OH](1), [Ni(dpa)CH3OH] (2), [Cu(bipy)2(Hdpa)2(H2O)2] (3) and [Ni(bipy)2(Hdpa)2(H2O)2] (4) (bipy = 4, 4′-bipyridine). The dinuclear paddle-wheel second building units (SBUs) constructed by four dpa2− ligands in complexes 1 and 2 are linked by dpa2− into double chains, which are connected by C-H?π interactions forming a two-dimensional rhombic porous structure. In complexes 3 and 4, the metal ions are connected by bipy ligands, and the grid-like network was formed with the π-π interactions between the adjacent phenyl rings of Hdpa−. For 1 and 2, there are strong antiferromagnetic interactions within Cu-Cu and Ni-Ni dimers. It is also strong antiferromagnetic interactions between the dimmers of Cu2 in 1, while it is weaker of those of Ni2 in 2. Weaker antiferromagnetic interactions exist among Cu-Cu and Ni-Ni in 3 and 4, in which bipy is the effective coupling media. Thermally gravimetric analyses and differential thermal analyses indicate that the four complexes are all thermal stable. 相似文献
9.
Jacqueline S. Lucas 《Inorganica chimica acta》2011,378(1):269-279
Hydrothermal synthesis has afforded cobalt 5-substituted isophthalate complexes with 4,4′-dipyridylamine (dpa) ligands, showing different dimensionalities depending on the steric bulk and hydrogen-bonding facility of the substituent. [Co(tBuip)(dpa)(H2O)]n (1, tBuip = 5-tert-butylisophthalate) is a (4,4) grid two-dimensional coordination polymer featuring 2-fold parallel interpenetration. [Co(MeOip)2(Hdpa)2] (2, MeOip = 5-methoxyisophthalate) is organized into 3-fold parallel interpenetrated (4,4) grids through strong N-H+?O− hydrogen bonding. {([Co(OHip)(dpa)(H2O)3])3·2H2O}n (3, OHip = 5-hydroxyisophthalate) possesses 1-D chain motifs. The 5-methyl derivative {[Co(mip)(dpa)]·3H2O}n (4, mip = 5-methylisophthalate) has a 3-D 658 cds topology. {[Co(H2O)4(Hdpa)2](nip)2·2H2O} (5, nip = 5-nitroisophthalate) and {[Co(sip)(Hdpa)(H2O)4]·2H2O} (6, sip = 5-sulfoisophthalate) are coordination complexes. Antiferromagnetic superexchange is observed in 1 and 4, with concomitant zero-field splitting. Thermal decomposition behavior of the higher dimensionality complexes is also discussed. 相似文献
10.
Yue Zhao 《Inorganica chimica acta》2011,377(1):138-143
Four new coordination complexes [Cd(DPBA-3)2(H2O)2](ClO4)2·2H2O (1), [Cd(DPBA-3)(DMF)(NO3)2]·DMF (2), [Cd3(DPBA-3)2(SCN)6]·2DMF·4H2O (3) and [Zn(DPBA-3)(SCN)2] (4) [DPBA-3 = N,N′-di(pyridin-3-yl)pyridine-3,5-dicarboxamide] have been synthesized and characterized by elemental analysis, IR and single crystal X-ray diffraction. Complexes 1, 3 and 4 exhibit three different types of one-dimensional (1D) chain structures constructed by the metal ions and DPBA-3 ligands, and the Cd(II)-DPBA-3 1D chains in 3 are further linked by bridging SCN− ligands to afford a three-dimensional (3D) framework. Complex 2 possesses a (6,3) two-dimensional (2D) layer structure. In 1-4, the hydrogen bonds involving the amide groups play important role to stabilize the resultant frameworks. The photoluminescence properties of the DPBA-3 and the complexes were studied in the solid state at room temperature. 相似文献
11.
Four new fluconazole-bridged zinc(II) and cadmium(II) complexes with dicarboxylate co-ligands, namely [Zn(HFlu)(TPA)]n (1), {[Cd(HFlu)2(TPA)]·2CH3OH}n (2), [Zn(HFlu)2(Suc)(H2O)2]·H2O (3), and [Cd(HFlu)2(Suc)(H2O)2]·H2O (4), have been synthesized and characterized by elemental analysis, IR, TG, and single-crystal X-ray diffraction (HFlu = 2-(2,4-difluorophenyl)-1,3-bis(1,2,4-triazol-1-yl)-propan-2-ol, H2TPA = terephthalic acid, and H2Suc = succinic acid). Complex 1 displays a 2-D corrugated network with common (4,4) topology, in which two types of grids constructed by two bridging TPA dianions and two HFlu ligands are found. Complex 2 shows an unusual (3,6) coordination layer consisting of alternative PMPM Cd-HFlu helical chains in which the Cd(II) nodes are also fixed by terephthalate dianions in a cis fashion. The isostructural complexes 3 and 4 have 20-membered dimeric macrocyclic motifs with the Zn···Zn and Cd···Cd distances of 11.258(2) and 11.528(2) Å, respectively. The fluorescence and thermal stability of complexes 1-4 have also been investigated. 相似文献
12.
A series of coordination polymers have been prepared by the combination of flexible ligand 1,1′-biphenyl-2,2′-dicarboxylic acid (H2dpa) and different types of nitrogen-containing ligands, with various metal ions such as Co(II), Zn(II) and Cd(II). The single-crystal structure analyses reveal that the above complexes possess different structure features with the introduction of different nitrogen-containing ligands. When auxiliary linear ligand 4,4′-bipyridine (4,4′-bpy) is introduced, two-dimensional layered complex, [Co2(dpa)2(4,4′-bpy)2(H2O)]n (1) is formed. Whereas if chelating ligand, 1,10-phenanthroline (1,10′-phen) and 2,2′-bipyridine (2,2′-bpy) are introduced, one-dimensional complex [Zn(dpa)(1,10′-phen)]n (2) and discrete complexes [Co2(dpa)2(2,2′-bpy)2(H2O)2] (3), [Co3(dpa)3(1,10′-phen)6(H2O)2] (4), [Cd(dpa)(1,10′-phen)2][(H2dpa)2(H2O)2] (5) are synthesized. To our interest, 1 and 2 crystallize in homochiral spacegroup. Furthermore, the magnetic property of complex 1 and the fluorescent properties of complexes 2 and 5 are studied. 相似文献
13.
Rampal Pandey Prashant Kumar Sanjay Kumar Singh Daya Shankar Pandey 《Inorganica chimica acta》2011,376(1):195-206
The synthesis and characterization of novel coordination polymers [Co(HCCB)(H2O)2]n (1), [Zn(HCCB)(H2O)2]n (2), {[Cd(HCCB)2]·0.5[Cd(μ-H2O)(H2O)4]2}n (3) and [Cu(HCCB)(H2O)2]n (4) based on 3-(carboxymethylamino)-4-chlorobenzoic acid (H3CCB) and mononuclear complexes [Cu(HBCCB)(H2O)]·H2O (5), [Co(HBCCB)(H2O)]·H2O (6), [Zn(HBCCB)(H2O)] (7) and [Cd(HBCCB)(H2O)] (8) containing 3-bis(carboxymethylamino)-4-chlorobenzoic acid (H3BCCB) have been described. The compounds under investigation have been characterized by elemental analyses, spectral studies and structures of 1-3 and 5 determined crystallographically. Structural data of 1 and 2 revealed that the deprotonated HCCB2− bridges metal centers leading to a double stranded 1D chain. On the other hand, the HCCB2− coordinated thorough carboxylate oxygen and amino nitrogen in 3 to afford a 1D chain whose charge neutrality is maintained by inclusion of aqua-bridged dimer [{Cd(μ-H2O)(H2O)4}2]4+. Strong Cu?Cl interaction (2.754 Å) in 5 imposes a coordination geometry that is half-way between the square planar and square pyramidal. The H3CCB, H3BCCB and 1-3 and 5 are fluorescent at rt. Thermal studies (TG and DSC) on 1-3 suggested higher stability of 2 relative to 1 and 3 [ΔHf (kcal/mol), ΔSf = 152.17, 0.60, 1; 195.56: 0.86, 2; 69.33:0.36, 3]. 相似文献
14.
A new bis(macrocycle) ligand, 7,7′-(2-hydoxypropane-1,3-diyl)-bis{3,7,11,17-tetraazabicyclo[11.3.1]heptadeca-1(17),13,15-triene} (HL), and its dicopper(II) ([Cu2(HL)Cl2](NO3)2 · 4H2O (4a), [Cu2(HL)I2]I2 · H2O (4b)) and dinickel(II) ([Ni2(L)(OH2)](ClO4)3 (5a), [Ni2(L)(OH2)]I3 · 2H2O (5b), [Ni2(L)N3](N3)2 · 7H2O (5c)) complexes have been synthesized. The alkoxide bridged face-to-face structure of the dinickel(II) complex 5c has been revealed by X-ray crystallography, as well as the “half-opened clamshell” form of the bis(macrocyclic) dicopper(II) complex 4b. Variable temperature magnetic susceptibility studies have indicated that there exists intramolecular antiferromagnetic coupling (J=−33.8 cm−1 (5a), −32.5 cm−1 (5b), and −29.7 cm−1 (5c)) between the two nickel(II) ions in the nickel(II) complexes. 相似文献
15.
Augustin M. Madalan Mirela Neculai Marc Schmidtmann Yves Journaux 《Inorganica chimica acta》2006,359(2):459-467
Three new homopolynuclear complexes with azido bridges have been obtained by using [Cu(AA)(BB)]+ building-blocks (AA = acetylacetonate; BB = 1,10-phenanthroline or 2,2′-bipyridine). The reaction between [Cu(acac)(phen)(H2O)](ClO4) and NaN3 leads to a mixture of two compounds: a binuclear complex, [{Cu(acac)(phen)}2(μ1,3-N3)](ClO4) · 2H2O (1), and a linear tetranuclear one, [{Cu(acac)(phen)(ClO4)}2{Cu(phen)(μ1,1-N3)2}2] (2). The reaction between [Cu(acac)(bipy)(H2O)](ClO4) and NaN3 affords also a mixture of two compounds: [{Cu(acac)(bipy)}2(μ1,3-N3)]3(ClO4)3 · 3.75H2O (3) and [Cu(acac)(bipy)(N3)][Cu(acac)(bipy)(H2O)](ClO4) (4). The X-ray crystal structures of compounds 1-4 have been solved (for compound 4 the crystal structure was previously reported). In compounds 1 and 3, two {Cu(AA)(BB)} fragments are bridged by the azido anion in an end-to-end fashion. Two isomers, cis and trans with respect to azido bridge, were found in crystal 3. The structure of compound 2 consists of two Cu(II) central cations bridged by two μ1,1-azido ligands, each of them being also connected to a {Cu(acac)(phen)} fragment through another μ1,1-azido ligand. The cryomagnetic properties of the compounds 1 and 2 have been investigated and discussed. The magnetic behaviour of compound 1 shows the absence of any interactions between the metallic ions. In the tetranuclear complex 2, the magnetic interactions between the external and central copper(II) ions(J1), and between the central metallic ions (J2) were found ferromagnetic (J1 = 0.36 cm−1, J2 = 7.20 cm−1). 相似文献
16.
Brajagopal Samanta Shyamapada Shit Paul Jensen Samiran Mitra 《Inorganica chimica acta》2007,360(7):2471-2484
Four new coordination complexes, NiII(L)2 (1), [CoIII(L)2]ClO4 (2), [Zn(HL)(L)]ClO4 · H2O (3) and [Zn(L)2][Zn(L)(HL)]ClO4 · 7H2O (4) (where L is a monoanion of a Schiff base ligand, N′-[(2-pyridyl)methylene]salicyloylhydrazone (HL) with NNO tridentate donor set), have been synthesised and systematically characterised by elemental analysis, spectroscopic studies and room temperature magnetic susceptibility measurements. Single crystal X-ray diffraction analysis reveals that 1 is a neutral complex, while 2-4 are cationic complexes. Among them, 4 is a rare type of cationic complex with two molecules in the asymmetric unit. The ligand chelates the metal centre with two nitrogen atoms from the pyridine and imino moieties and one oxygen atom coming from its enolic counterpart. All the reported complexes show distorted octahedral geometry around the metal centres, with the two metal-N (imino) bonds being significantly shorter than the two metal-N (Py) bonds. 相似文献
17.
Hydrothermal synthesis has afforded a family of three structurally related metal phthalate (pht) 1-D coordination polymers incorporating the kinked dipodal organodiimine 4,4′-dipyridylamine (dpa), with a general formulation of [L2M(dpa)2M(H2O)4] · H2O (L = pht, M = Co, 1, M = Ni, 2; L = 4-methylphthalate (4-mpht), M = Co, 3). Single crystal X-ray diffraction of 1 and 2 revealed the presence of one-dimensional (1-D) polymeric chains consisting of [M(H2O)4]2+ and [M(pht)2]2− subunits linked through dpa tethers. These chains in turn conjoin into pseudo 2-D layers and 3-D networks via extensive supramolecular hydrogen bonding pathways. An extremely similar structure is observed for 3 despite the presence of the bulkier methyl group substituent. 1-3 were further characterized via infrared spectroscopy and elemental and thermogravimetric analysis. 1-3 represent the first dicarboxylate coordination polymers incorporating dpa tethering ligands. 相似文献
18.
Two Cd(II) and Zn(II) coordination polymers based on 3,3′,5,5′-azobenzenetetracarboxylic acid (H4abtc): [Cd2(abtc)(H2O)6]·DMF·0.5H2O (1) and [Zn2(abtc)(bpy)(H2O)2]·DMF·H2O (2) are synthesized and structurally characterized. Both 1 and 2 are 2D polymers but interconnected by solvent molecules to generate 3D suprastructures. Solvent expulsion leads to rupture of both structures, but upon re-exposure to the solvent mixture they exhibit remarkable ability to regain the original structure reversibly from the almost amorphous solvent-expelled form. Compounds with such structural flexibility and reversibility are expected to have some useful functionality. 相似文献
19.
New ternary transition metal complexes of formulations [Ni(bpa)(p-AB)Cl]n · 3nH2O (bpa = 2,2′-bipyridylamine, p-AB = aminobenzenecarboxylic acid) (1), [Cu(bpa)(p-AB)Cl] · H2O (2), [Zn(bpa)(p-AB)2] · H2O (3) are prepared, their structural features are characterized by crystal structural studies, and their DNA binding propensity has been evaluated by fluorescence and viscosity method. In complex 2 and 3, both bpa and p-AB act as the bidentate N and O-donor ligand, respectively. While in complex 1, p-AB acts as a rare tridentate ligand. In the packing pattern of each complex, π-π interaction in their solid state is also described. The complexes show the competitive inhibition of ethidium binding to DNA, and the DNA binding propensity can be reflected as the relative order: 1 > 2 > 3. 相似文献
20.
[Pd(sac)(terpy)](sac)·4H2O (1), [Pt(sac)(terpy)](sac)·5H2O (2), [PdCl(terpy)](sac)·2H2O (3) and [PtCl(terpy)](sac)·2H2O (4) (sac = saccharinate, and terpy = 2,2′:6′,2″-terpyridine) have been synthesized and characterized by elemental analysis, FT-IR, 1H NMR and 13C NMR. In 1 and 2, a tridentate terpy ligand together with an N-coordinated sac ligand form the square-planar geometry around the palladium(II) or platinum(II) ions, while one sac anion remains outside the coordination sphere as a counter-ion. X-ray single crystal studies show that the [M(sac)(terpy)]+ ions in 1 and 2 reside in the centers of a hydrogen bonded honeycomb network formed by the uncoordinated sac ions and the lattice water molecules. Complexes 3 and 4 are isostructural and consist of a [M(Cl)(terpy)]+ cation, a sac anion and two lattice water molecules. The [M(Cl)(terpy)]+ ions interact with each other via M-M and π-π stacking interactions and these π interacted units are assembled to a 2D network by water bridges involving the sac ions and lattice water molecules. Convenient synthetic paths for 1-4 are also presented, and spectral, luminescence and thermal properties were discussed. 相似文献