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1.
Three novel silver(I) complexes with 1,2-bis(2-methyl-5′-(2″-pyridyl)-3′-thienyl)perfluorocyclopentene (BM-2-PTP) were synthesized by the reaction of Ag(CF3SO3) or Ag(CF3COO) with BM-2-PTP in benzene at different temperatures. The structures of these metal complexes were revealed by X-ray crystallographic analyses and the correlation between crystal structures and photochromic performance was discussed. In complexes 1 and 2, silver(I) is three-coordinated to two nitrogens from distinct ligand molecules as well as one oxygen from anions to form a 1-D polymeric structure. On the other hand, complex 3 contains two crystallographic independent Ag(I) with different coordination environments, and the adjacent BM-2-PTP molecules are connected by Ag-CF3CO2-Ag chains to afford a 1-D double chain structure. The difference in structures of three complexes shows the interesting anionic effect on coordination and the subtleness of crystal engineering. It is noted that complex 3 underwent reversible photochromic reaction in crystalline state despite the unfavorable framework to the rotation of thiophene groups.  相似文献   

2.
The new complex, [RuII(bpy)2(4-HCOO-4′-pyCH2 NHCO-bpy)](PF6)2 · 3H2O (1), where 4-HCOO-4′-pyCH2NHCO-bpy is 4-(carboxylic acid)-4′-pyrid-2-ylmethylamido-2,2′-bipyridine, has been synthesised from [Ru(bpy)2(H2dcbpy)](PF6)2 (H2dcbpy is 4,4′-(dicarboxylic acid)-2,2′-bipyridine) and characterised by elemental analysis and spectroscopic methods. An X-ray crystal structure determination of the trihydrate of the [Ru(bpy)2(H2dcbpy)](PF6)2 precursor is reported, since it represented a different solvate to an existing structure. The structure shows a distorted octahedral arrangement of the ligands around the ruthenium(II) centre and is consistent with the carboxyl groups being protonated. A comparative study of the electrochemical and photophysical properties of [RuII(bpy)2(4-HCOO-4′-pyCH2NHCO-bpy)]2+ (1), [Ru(bpy)2(H2dcbpy)]2+ (2), [Ru(bpy)3]2+ (3), [Ru(bpy)2Cl2] (4) and [Ru(bpy)2Cl2]+ (5) was then undertaken to determine their variation upon changing the ligands occupying two of the six ruthenium(II) coordination sites. The ruthenium(II) complexes exhibit intense ligand centred (LC) transition bands in the UV region, and broad MLCT bands in the visible region. The ruthenium(III) complex, 5, displayed overlapping LC bands in the UV region and a LMCT band in the visible. 1, 2 and 3 were found, via cyclic voltammetry at a glassy carbon electrode, to exhibit very positive reversible formal potentials of 996, 992 and 893 mV (versus Fc/Fc+) respectively for the Ru(III)/Ru(II) half-cell reaction. As expected the reversible potential derived from oxidation of 4 (−77 mV (versus Fc/Fc+)) was in excellent agreement with that found via reduction of 5 (−84 mV (versus Fc/Fc+)). Spectroelectrochemical experiments in an optically transparent thin-layer electrochemical cell configuration allowed UV-Vis spectra of the Ru(III) redox state to be obtained for 1, 2, 3 and 4 and also confirmed that 5 was the product of oxidative bulk electrolysis of 4. These spectrochemical measurements also confirmed that the oxidation of all Ru(II) complexes and reduction of the corresponding Ru(III) complex are fully reversible in both the chemical and electrochemical senses.  相似文献   

3.
Nano-scale and single crystals of a new MnII complex, {[Mn(pyterpy)(H2O)(NCS)1.88Cl0.12] · DMF} (1) [pyterpy = 4′-(4-pyridyl)-2,2′:6′,2″-terpyridine] have been synthesized by the reaction of pyterpy and mixtures of manganese(II) acetate and potassium thiocyanate as well as potassium chloride using sonochemical and heat gradient methods, respectively. The nano-structure was characterized by IR spectroscopy and scanning electron microscopy (SEM), and the structure of compound 1 was determined by single-crystal X-ray diffraction. Thermal stability and catalytic properties of nanoparticles and single crystalline samples of compound 1 were studied and are compared with each other.  相似文献   

4.
Compounds of the molecular formulae, [LH3](NO3)3 (1), [Fe(LH)2](PF6)4·5H2O (2), [Fe(L)2][Fe(L)(LH)](PF6)5·H2O (3), [Fe(L)2][Fe(L)(LH)](BF4)5·2H2O (4) and [Fe(L)2](Cr2O7)·6H2O (5) have been synthesized using 4′-(2-pyridyl)-2,2′:6′,2″-terpyridine (L). The molecular structures of all the compounds were determined. The Fe(II) complexes are high spin in nature at room temperature and upon cooling a gradual spin-transition is observed. Among 1-5, hydrogen-bonding, π···π, and anion···π interactions as well as water tetramer and pentamer are present in the molecular packing.  相似文献   

5.
By the reactions of Cu(AcO)2·H2O and Cu(HCOO)2·4H2O with 4,4′-dimethyl-2,2′-bipyridine and 5,5′-dimethyl-2,2′-bipyridine the compounds [Cu(AcO)2(4,4′-Me2-2,2′-bipy)]·1/2H2O (1), [Cu(AcO)2(5,5′-Me2-2,2′-bipy)(H2O)] (2), [Cu(HCOO)(μ-HCOO)(4,4′-Me2-2,2′-bipy)]n·nH2O (3) and [Cu(HCOO)(μ-HCOO)(5,5′-Me2-2,2′-bipy)]n·2nH2O (4) were obtained. In the acetate complexes, 1 and 2, the geometry around copper is distorted octahedral and square pyramidal, respectively. Dimeric units of different geometry are formed in both cases through hydrogen bonds in which non-coordinated (in 1) and coordinated (in 2) water molecules are involved. The structures of 3 and 4 consist of polymeric monodimensional chains of square pyramidal copper units linked by axial-equatorial syn-anti (3) or anti-anti (4) bridging formate groups. Water molecules form hydrogen bonds with formate groups of the same chain in compound 3. In compound 4 the water molecules link the polymeric contiguous chains of complex through hydrogen bonds with oxygen atoms of formate groups and they are also linked between them, forming monodimensional water chains which run parallel to the complex chains. Sheets parallel to the ac plane are formed by alternating chains of water and polymeric complex. Magnetic properties and EPR spectra for these compounds have been studied.  相似文献   

6.
Four lanthanide coordination polymers, [{Ln2(bpdc)3(phen)2(H2O)2} · (H2O)6]n (Ln = Sm (1); Eu (2); Gd (3), Tb (4)), were self-assembled from 2,2′-bipyridine-3,3′-dicarboxylic acid (H2bpdc),1,10-phenanthroline(phen) and corresponding lanthanide oxides by hydrothermal synthesis. Compounds 1-4 are found to be isomorphous and isostructural. Single-crystal X-ray diffraction studies show that compounds 1-4 are all of one-dimensional zigzag chain structures and extend to two-dimensional networks through π-π interactions and hydrogen bonds. The pyridyl nitrogen atoms of the 2,2′-bipyridyl unit in the bpdc ligand are uncoordinated in an anti-conformation along the central C-C bond of the ligand. Thermogravimetric analysis of 1-4 showed an obvious thermal stability indicating that the coordination habit of the metal ions with bpdc and phen has an effect on the overall framework. Photoluminescence measurement indicates that compound 2 and compound 4 are strong red and green emitters, respectively.  相似文献   

7.
A series of [Cu(I)(2,2′-biquinoline)(L)](ClO4) complexes (L = bis(diphenylphosphino)methane (bppm), 1,2-bis(diphenylphosphino)ethane (bppe), 1,4-bis(diphenylphosphino)butane (bppb)) have been synthesized and characterized by elemental analysis, conductivity, ESI-mass, NMR and UV-Vis spectroscopies, cyclic voltammetry, X-ray diffraction ([Cu(I)(2,2′-biquinoline)(bppe)](ClO4)) and DFT calculations. These compounds are monometallic species in a distorted tetrahedral arrangement, in contrast with related compounds found as dinuclear according to diffraction studies. The spectroscopic properties are not directly correlated with the length of alkyl chain bridge between the bis-diphenylphosphine groups. In this way, the chemical shift of some 2,2′-biquinoline protons and the metal to ligand charge transfer (Cu to 2,2′-biquinoline) follows the order [Cu(2,2′-biquinoline)(bppm)](ClO4), [Cu(2,2′-biquinoline)(bppb)](ClO4), [Cu(2,2′-biquinoline)(bppe)](ClO4). The same dependence is followed by the potentials to Cu(II)/Cu(I) couple. These results are discussed in terms of inter-phosphorus alkane chain length and tetrahedral distortions on copper.  相似文献   

8.
One-dimensional (1-D) helical coordination polymers, [MII(H2O)3(BPDC)]n · nH2O (M = Co (1), Fe (2)), have been prepared by the self-assembly of cobalt(II) and iron(II) ions, respectively, with 2,2′-bipyridyl-3,3′-dicarboxylic acid (H2BPDC) in an aqueous solution. X-ray crystal structures of compounds 1 and 2 show that each metal ion displays a distorted octahedral coordination geometry including three water oxygen atoms, one oxygen atom of the carboxylate of a BPDC2− belonging to the adjacent metal ion and two nitrogen atoms from the BPDC2− acting as a chelating ligand. In 1 and 2, one carboxylate oxygen atom of coordinated BPDC2− binds to the neighboring metal ion, which give rise to 1-D helical coordination polymers. The helical chains of 1 and 2 are linked by the hydrogen bonding interactions between the carboxylate oxygen atom of the BPDC2− ion belonging to a chain and the water molecule of the adjacent helical chain, which lead to 2-D networks extending along the ab plane. The supramolecules 1 and 2 show isomorphous structures regardless of the metal ions.  相似文献   

9.
A novel bridging ligand 2,2′-bis(1,2,4-triazino[5,6-f]phenanthren-3-yl)-4,4′-bipyridine (btpb) and its mononuclear ruthenium(II) complex [Ru(bpy)2(btpb)]2+ (Rubtpb; bpy = 2,2′-bipyridyl) and dinuclear ruthenium(II) complex [Ru(bpy)2(btpb)Ru(bpy)2]4+ (Ru2btpb) have been synthesized and characterized by elemental analyses, fast atom bombardment or electrospray mass spectra, 1H NMR, and electronic spectroscopy. Binding behaviors of the mono- and dinuclear complexes with calf thymus DNA (CT-DNA) have been investigated by absorption spectra, viscosity measurements, and equilibrium dialysis experiments. As the concentration of DNA is increased, the electronic absorption spectra bands at the metal-ligand charge transfer of the mononuclear complex Rubtpb at 501.0 nm exhibit hypochromism of about 17.4% and bathochromism of 2.0 nm, the dinuclear complex Ru2btpb at 511.0 nm exhibits hypochromism of about 24.8% and bathochromism of 1.0 nm. The increasing amounts of the complexes on the relative viscosities of CT-DNA are much smaller than that of the classic intercalators. The experiments suggest that the Rubtpb and Ru2btpb may be bound to DNA by non-intercalating binder.  相似文献   

10.
The synthesis and characterisation of [Pt{4′-(Np1)-trpy}(CCPh)]SbF6 (1) and [Pt{4′-(Np1)-trpy}{CC(CH2)2CH3}]SbF6 (2) [4′-(Np1)-trpy = 4′-(1-naphthyl)-2,2:6′,2′-terpyridine] are described. Complexes 1 and 2 exhibit unimolecular 3MLCT (MLCT = metal-to-ligand charge transfer) emission in acetonitrile and in a low concentration 77 K glass solution in butyronitrile. The high concentration glass emission as well as the emission in the solid state is from a 3MMLCT (MMLCT, metal-metal-to-ligand charge transfer) excited state, reflecting the presence of interactions in these media.  相似文献   

11.
Bin Hu 《Inorganica chimica acta》2010,363(7):1348-6199
Four transition metal complexes of 3,8-di(thiophen-2′,2″-yl)-1,10-phenanthroline (dtphen), formulated as [Ni(dtphen)2(H2O)2]·(ClO4)2 (1), [Zn(dtphen)2(H2O)]·(ClO4)2 (2) [Cu(dtphen)2(H2O)]·(ClO4)2 (3), [Cu(dtphen)(phen)2]·(ClO4)2 (4) (phen = 1,10-phenanthroline) with different metal-to-ligand ratios, were synthesized and characterized herein. The X-ray single-crystal diffraction studies of 1-4 exhibit that different molecular configurations for the dtphen ligand can be observed where the side thiophene rings adopt the trans/trans, trans/cis, trans/disorder and cis/cis conformations relative to the central 1,10-phenanthroline unit in different compounds. Fluorescence emission spectra of 1-4 in methanol show that the fluorescence emission of 2 is much stronger than the other three metal complexes, which is mainly due to its full d10 electronic configuration of Zn(II) ion.  相似文献   

12.
The reactions of 4-(p-dimethylaminophenyl)-6-phenyl-2,2′-bipyridine (HL) with three metal salts of platinum(II), copper(I) and zinc(II) provide the new complexes [Pt(L)(PPh3)]ClO4 (1), [Cu(HL)2]BF4 (2), [Cu(HL)(PPh3)]BF4 (3) and [Zn(HL)2](ClO4)2 (4). All the structures of these four complexes have been characterized by single crystal X-ray diffraction, and their spectroscopic properties were investigated. Especially for complex 1, upon protonation, the excited state can be tuned from the intraligand charge transfer (ILCT) to the metal-to-ligand charge transfer (MLCT), and such switching in the excited state is acid/base reversible. The time-dependent density functional theory (TD-DFT) calculation was used to interpret the absorption spectra of complex 1, and the calculated result is consistent with those of experiments results. In contrast with 1, the lowest energy absorption at 410-650 nm of complexes 2 and 3 can be assigned to MLCT excited state. In solid state or solution complex 4 exhibits intense photoluminescence attributed to a ILCT transition in nature.  相似文献   

13.
We herein describe the synthesis and characterization of a series of homoleptic, Ru(II) complexes bearing peripheral carboxylic acid functionality based upon the novel ligand 4′-(4-carboxyphenyl)-4,4″-di-(tert-butyl)tpy (L1), as well as 4′-(4-carboxyphenyl)tpy (L2) and 4′-(carboxy)tpy (L3) (where tpy = 2,2′: 6′,2″-terpyridine). Inspection of the metal-based oxidations (E1/2 = 1.22-1.42 V) indicates an anodic shift (∼0.2 V) for (L3)2Ru2+ (3b) (E1/2 = 1.40 V) relative to (L2)2Ru2+ (2b) (E1/2 = 1.22 V). The metal-based oxidation (E1/2 = 1.22 V) and ligand-based reductions (E1/2 = −1.25 to −1.52 V) of (L1)2Ru2+ (1) are essentially invariant relative to those of the structural analogue 2b (PF6)2, which suggests no significant electronic effect caused by the tert-butyl groups. This is supported by invariance in the metal-to-ligand charge transfer bands in both the electronic absorption (494-489 nm) and emission spectra (654-652 nm). However, contrary to 2b, complex 1 is both very soluble and exhibits a highly porous solid-state structure with internal cavity dimensions of 15 Å × 14 Å due to the preclusion of inter-annular interactions by the bulky tert-butyl substituents.  相似文献   

14.
The dinuclear complex [Cu2(dpbp)2(NCMe)4][BF4]2 (1) has been prepared by treating [Cu(NCMe)4][BF4] with 4,4′-bis(diphenylphosphino)biphenylene (abbreviated as dpbp). Reactions of 1 with 2,2′-bipyridine and 1,1′-bis(diphenylphosphino)ferrocene (abbreviated as dppf) afford [Cu2(dpbp)2(2,2′-bipy)2][BF4]2 (2) and [Cu2(dpbp)(dppf)2][BF4]2 (3), respectively. In contrast, compound 1 reacts with tetra(2-pyridyl)ethyl-1,4-diaminobutane (abbreviated as tpyda) to produce the polymeric complex {[Cu2(dpbp)(tpyda)][BF4]2}n (4). Compounds 1-4 are photoluminescent with the emission band (λmax) in the range 510-554 nm. The crystal structures of 1 and 4 have been determined by an X-ray diffraction study.  相似文献   

15.
Reaction of [Mn(2,2′-bpy)2(OAc)](ClO4)(H2O) with a series of aromatic carboxylic acids yields new Mn(II)carboxylates [Mn(2,2′-bpy)2(L)](ClO4)}2 (1-3), [Mn(2,2′-bpy)2(L)2] (4-5) and [Mn(2,2′-bpy)2(L)(H2O)](ClO4) (6) (L = 2-aminobenzoate (2-aba) (1), 4-hydroxybenzoate (4-hba) (2), thiophene-2-carboxylate (2-tca) (3), 2-hydroxynapthoate (2-hnapa) (4), 3,5-diisopropylsalicylic acid (dipsa) (5), 2,4,6-triisopropylbenzoate (tipba) (6)). The new compounds have been characterized with the aid of elemental analysis, spectroscopy, and single-crystal X-ray diffraction studies. Compounds 1-3, which have been synthesized from less bulky carboxylic acids, are dimeric in the solid-state. Compounds 4-6, which are derived from more bulkier aromaric carboxylic acids, exist as monomeric complexes. In the case of 6, where very bulky 2,4,6-triisopropyl benzoic acid is used as the starting material, only one carboxylate ligand binds to the metal, resulting in a cationic complex. Interestingly in all the six complexes, the C-H hydrogen atoms of the 2,2′-bpy ligands are involved in extensive hydrogen bonding with the carboxylate oxygen atoms of the adjacent molecules and hence form non-covalent 1-D or 2-D aggregates in the solid state.  相似文献   

16.
Reaction of 4,4′-di(3-pyridyl-4-pyrimidinyl) disulfide (3-PPDS) with AgNO3 leads to a unique 2D extended structure {[Ag(3-PPDS)(NO3)]}n (1) based on [Ag2(3-PPDS)2] macrocycle units, of which 1D inorganic [Ag(NO3)]n helical chains are generated. By contrast, definite Ag-S bonding interactions associated with the disulfide function have been established in {[Ag(2-PPDS)]ClO4}n (2), which is assembled of 4,4′-di(2-pyridyl-4-pyrimidinyl) disulfide (2-PPDS) with AgClO4. Solid state luminescent properties of complexes 1 and 2 are also examined.  相似文献   

17.
The preparation, crystal structure and variable temperature-magnetic investigation of three 2-(2′-pyridyl)imidazole-containing chromium(III) complexes of formula PPh4[Cr(pyim)(C2O4)2]·H2O (1), AsPh4[Cr(pyim)(C2O4)2]·H2O (2) and [Cr2(pyim)2(C2O4)2(OH2)2]·2pyim · 6H2O (3) [pyim = 2-(2′-pyridyl)imidazole, , and ] are reported herein. The isomorphous compounds are made up of discrete [Cr(pyim)(C2O4)2] anions, cations [X = P (1) and As (2)] and uncoordinated water molecules. The chromium environment in 1 and 2 is distorted octahedral with Cr-N and Cr-O bond distances varying in the ranges 2.040(3)-2.101(3) and 1.941(3)-1.959(3) Å, respectively. The angle subtended by the chromium(III) ion by the two didentate oxalate ligands cover the range 82.49(12)-82.95(12)°, values which are somewhat greater than those concerning the chelating pyim molecule [77.94(13) (1) and 78.50(13)° (2)]. Complex 3 contains discrete centrosymmetric [Cr2(pyim)2(C2O4)2(OH)2] neutral units where the two chromium(III) ions are joined by a di-μ-hydroxo bridge, the oxalate and pyim groups acting as peripheral didentate ligands. Uncoordinated water and pyim molecules are also present in 3 and they contribute to the stabilization of its structure by extensive hydrogen bonding and π-π type interactions. The values of the intramolecular chromium-chromium separation and angle at the hydroxo bridge in 3 are 2.9908(12) Å and 99.60(16)°, respectively. Magnetic susceptibility measurements of 1-3 in the temperature range 1.9-300 K show the occurrence of weak inter- (1 and 2) and intramolecular (3) antiferromagnetic couplings. The magnetic properties of 3 have been interpreted in terms of a temperature-dependent exchange integral, small changes of the angle at the hydroxo bridge upon cooling being most likely responsible for this peculiar magnetic behavior.  相似文献   

18.
Seven copper complexes [Cu(L1)I2] (1), [Cu2(L1)2I2]2[Cu2(μ-I)2I2] (2), [Cu(L2)I2] (3), [Cu2(L2)(μ-I)I(PPh3)] (4), [Cu4(L2)2(μ-I)2I2] (5), {[Cu(L2)I]2[Cu2(μ-I)2I2]}n (6) and [Cu2(L2)(μ-I)2]n (7) have been prepared by reactions of ligands: 4′-(2-pyridyl)-2,2′:6′,2″-terpyridine (L1) and 4′-(3-pyridyl)-2,2′:6′,2″-terpyridine (L2) with CuI in hydrothermal conditions, respectively. By alternating the oxidations states of the metal centers, increasing stoichiometric metal/ligand ratio and introducing a second ligand, the compounds, were successfully developed from mononuclear (1 and 3) to multinuclear (2, 4 and 5) and polymers (6 and 7). The synthesis of these compounds may provide an approach for the construction of coordination compounds of 4′-pyridyl terpyridine with different nuclearity.  相似文献   

19.
A mononuclear compound [Cd(dpaH)2(dca)2] (1) and a tetranuclear based 2D coordination polymer [Hg4(dpa)4(dca)4]n (2) [dpaH = 2,2′-dipyridylamine, dpa = anion of dpaH, dca = dicyanamide] have been synthesized and characterized. X-ray structural analyses reveal that cadmium(II) center in 1 has a distorted octahedral geometry with a CdN6 chromophore ligated through two bidentate neutral dpaH units along with two nitrile N atoms of two terminally bound dca units in mutual cis orientation. Each of the four independent mercury(II) centers in 2 adopts a distorted trigonal bipyramidal environment coordinated by two pyridine N atoms of two different anionic dpa ligands, two nitrile N atoms of two μ1,5 bridged dca units and the fifth position is occupied by the amide N of one dpa. Cooperative intermolecular N-H···N and C-H···N hydrogen bondings promote dimensionality in 1. The compounds display intraligand 1(π-π) fluorescence in DMF solutions at room temperature.  相似文献   

20.
We report the synthesis of a new ligand, 4,4′-bis(3,5-dimethoxyphenyl)-6,6′-dimethyl-2,2′-bipyridine, optimised for binding to copper(I) and with pendant functionality that can eventually be developed into metallodendritic structures. The synthesis and photophysical properties of complexes with copper(I) and ruthenium(II) are reported. The solid state structure of the complex [Cu(1)2][PF6] · MeCN (1 = 4,4′-bis(3,5-dimethoxyphenyl)-6,6′-dimethyl-2,2′-bipyridine) is also described.  相似文献   

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