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1.
4‐Hydroxypyridine‐2,6‐dicarboxylic acid (chelidamic acid, hypydc[H]H2) reacts with MnCl2·2H2O in the presence of piperazine in water to afford the title complex, {[Mn3(C7H2NO5)2(H2O)8]·3H2O}n or {[Mn3(hypydc)2(H2O)8]·3H2O}n. This compound is a one‐dimensional coordination polymer, with the twofold symmetric repeat unit containing three metal centres. Two different coordination geometries are observed for the two independent MnII metal centres, viz. a distorted pentagonal bipyramid and a distorted octahedron. The 4‐oxidopyridine‐2,6‐dicarboxylate anions and two of the water molecules act as bridging ligands. The zigzag‐like geometry of the coordination polymer is stabilized by hydrogen bonds. O—H...O and C—H...O hydrogen bonds and water clusters consolidate the three‐dimensional network structure.  相似文献   

2.
A series of five l ‐di‐p‐toluoyl‐tartaric acid (l ‐DTTA) lanthanide coordination polymers, namely {[Ln4K4 L6(H2O)x]?yH2O}n, [Ln=Dy ( 1 ), x=24, y=12; Ln=Ho ( 2 ), x=23, y=12; Ln=Er ( 3 ), x=24, y=12; Ln=Yb ( 4 ), x=24, y=11; Ln=Lu ( 5 ), x=24, y=12] have been isolated by simple reactions of H2L (H2L= L ‐DTTA) with LnCl3?6 H2O at ambient temperature. X‐ray crystallographic analysis reveals that complexes 1 – 5 feature two‐dimensional (2D) network structures in which the Ln3+ ions are bridged by carboxylate groups of ligands in two unique coordinated modes. Luminescent spectra demonstrate that complex 1 realizes single‐component white‐light emission, while complexes 2 – 4 exhibit a characteristic near‐infrared (NIR) luminescence in the solid state at room temperature.  相似文献   

3.
Three ZnII metal‐organic frameworks (Zn‐MOFs), [Zn2(tib)(HL1)(H2L1)0.5]?2H2O ( 1 ), [Zn2(tib)(L2)]?H2O ( 2 ) and [Zn3(tib)(L3)2(H2O)6]?2 H2O ( 3 ), have been prepared by reactions of 1,3,5‐tris(1‐imidazolyl)benzene (tib), and biphenyl‐3,3′,4,4′‐tetracarboxylic acid (H4L1), 4,4′‐oxydiphthalic acid (H4L2), or benzene‐1,3,5‐tricarboxylic acid (H3L3) with corresponding ZnII salts, respectively. Single crystal structure analyses reveal that 1 and 2 are constructed by Zn‐centered polyhedra, tib and multidentate tetracarboxylate ligands to form 3‐dimensional frameworks. In contrast, when the tetracarboxylate ligands were replaced by tricarboxylate ligand, layered structure of 3 is produced. These compounds are further characterized by powder X‐ray diffraction, element analyses, thermogravimetric analyses and photoluminescent spectroscopy. The luminescent properties of three Zn‐MOFs dispersed in different solvents have been investigated systematically, demonstrating high sensitivity for the detection of nitro compounds via a fluorescence quenching mechanism.  相似文献   

4.
Four compounds [Dy(H2bidc)(Hbidc)(H2O)8] · 8H2O ( 1 ), {[Dy(Hbidc)(H2O)2(Htzac)] · 3H2O}n ( 2 ), [Dy(C2O4)0.5(Hbidc)(H2O)3]n ( 3 ), {[Dy2(Hbidc)2(H2O)(SO4)] · H2O}n ( 4 ) (H3bidc = 1H‐benzimidazole‐5,6‐dicarboxylic acid, H2tzac = 1H‐3‐amino‐5‐carboxy‐1,2,4‐triazole) were synthesized with hydrothermal synthesis and structurally characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction. X‐ray analysis revealed that the four coordination compounds have different structures: Compound 1 is a three dimensional supermolecular structure joined by hydrogen bonding interactions based upon dinuclear units. Compound 2 is a three dimensional supermolecular structure combined by hydrogen‐bonding interactions based upon one dimensional coordination chain including a T4(1)‐type water cluster chain. The structure of compound 3 is built of two dimensional (3,6)‐connected kgd‐type (43)2(46.66.83) layers with a right‐handed and a left‐handed helical chain, which are further extended into three dimensional supramolecular architecture by hydrogen bonding interactions. Compound 4 displays a three dimensional framework containing a dinuclear dysprosium building unit with a (3,8)‐connected (4.52)2(42.510.612.7.83) topological framework. In addition, the photoluminescent property of compound 3 was investigated.  相似文献   

5.
A mixed ligand approach was exploited to synthesize a new series of MnII‐based coordination polymers (CPs), namely, CP1 {[Mn(μ‐dpa)(μ‐4,4′‐bp)]?MeOH}, CP2 {[Mn3(μ‐dpa)3(2,2′‐bp)2]}, CP3 {[Mn3(μ‐dpa)3(1,10‐phen)2]?2 H2O}, CP4 {[Mn(μ‐dpa)(μ‐4,4′‐bpe)1.5]?H2O}, CP5 {[Mn2(μ‐dpa)2(μ‐4,4′‐bpe)2]? DEF}, and CP6 {[Mn(μ‐dpa)(μ‐4,4′‐bpe)1.5]? DMA} (dpa=3,5‐dicarboxyphenyl azide, 2,2′‐bp=2,2′‐bipyridine, 1,10‐phen=1,10‐phenanthroline, 4,4′‐bpe=1,2‐bis(4‐pyridyl)ethylene, 4,4′‐bp=4,4′‐bipyridine, DEF=N,N‐diethylformamide, DMA=N,N‐dimethylacetamide), to develop multifunctional CPs. Various techniques, such as single‐crystal X‐ray diffraction (SXRD), FTIR spectroscopy, elemental analysis, and thermogravimetric analysis, were employed to fully characterize these CPs. The majority of the CPs displayed a four‐connected sql topology, whereas CP4 and CP6 exhibited a two‐dimensional SnS network architecture, which was further entangled in a polycatenation mode. Compound CP1 displayed an open framework structure. The CPs were scaled down to the nanoregime in a ball mill for cell imaging studies. Whereas CP2 and CP4 were employed for cell imaging with RAW264.7 cells, CP1 was exploited for both cell imaging and heterogeneous catalysis in a cyanosilylation reaction.  相似文献   

6.
The metal‐organic framework {[Zn2(CAM)(μ2‐OH)(bpp)] · 2H2O}n ( 1 ) [H3CAM = 4‐hydroxypyridine‐2,6‐dicarboxylic acid, bpp = 1,3‐bis(4‐pyridyl)propane], was hydrothermally synthesized and characterized by elemental analyses, infrared spectroscopy, and single‐crystal X‐ray diffraction. Compound 1 presents a three dimensional self‐penetrating 8‐connected framework with the Schläfli symbol 420.53.65. In addition, the fluorescent properties and thermal stability of 1 were discussed as well.  相似文献   

7.
Four metal‐organic frameworks (MOFs), {[Mn3.5L(OH)(HCOO)4(DMF)] · H2O} ( 1 ), {[In2.5L2O(OH)1.5(H2O)2] · DMF · CH3CN · 2H2O} ( 2 ), {[Pb4L3O(DMA)] · CH3CN} ( 3 ), and {[LaL(NO3)(DMF)2] · 2H2O} ( 4 ) were synthesized by utilizing the ligand 2,2′,6,6′‐tetramethoxy‐4,4′‐biphenyldicarboxylic acid (H2L) via solvothermal methods. All MOFs were characterized by single‐crystal X‐ray diffraction, powder X‐ray diffraction, thermogravimetric analysis, and infrared spectroscopy. In 1 , the Mn2+ ions are interconnected by formic groups in situ produced via DMF decomposition to form a rare 2D macrocyclic plane, which is further linked by L2– to construct the final 3D network. In 2 , 1D zip‐like infinite chain is formed and then interconnected to build the 3D framework. In 3 , a [Pb64‐O)2(O2C)10(DMA)2] cluster with a centrosymmetric [Pb64‐O)2]8+ octahedral core is formed in the 3D structure. In 4 , the La3+ ions are connected with each other through carboxylate groups of L2– to generate 1D zigzag chain, which is further linked by L2– to construct a 3D network with sra topology. Solid photoluminescence properties of 3 and 4 were also investigated.  相似文献   

8.
The imidazole‐based dicarboxylate ligand 2‐(4‐(pyridin‐4‐yl)phenyl)‐1H‐imidazole‐4,5‐dicarboxylic acid (H3PyPhIDC), was synthesized and its coordination chemistry was studied. Solvothermal reactions of CaII, MnII, CoII, and NiII ions with H3PyPhIDC produced four coordination polymers, [Ca(μ3‐HPyPhIDC)(H2O)2]n ( 1 ), {[M32‐H2PyPhIDC)23‐HPyPhIDC)26(H2O)2] · 6H2O}n [M = Mn ( 2 ), Co ( 3 )], and {[Ni(μ3‐HPyPhIDC)(H2O)] · H2O}n ( 4 ). Compounds 1 – 4 were analyzed by IR spectroscopy, elemental analyses, and single‐crystal and powder X‐ray diffraction. Compound 1 displays a one‐dimensional (1D) infinite chain. Compounds 2 and 3 are of similar structure, showing 2D network structures with a (4,4) topology based on trinuclear clusters. Compound 4 has another type of 2D network structure with a 3‐connected (4.82) topology. The results revealed that the structural diversity is attributed to the coordination numbers and geometries of metal ions as well as the coordination modes and conformations of H3PyPhIDC. Moreover, the thermogravimetric analyses of all the compounds as well as luminescence properties of the H3PyPhIDC ligand and compound 1 were also studied.  相似文献   

9.
A water‐stable luminescent terbium‐based metal–organic framework (MOF), {[Tb(L1)1.5(H2O)] ? 3 H2O}n (Tb‐MOF), with rod‐shaped secondary building units (SBUs) and honeycomb‐type tubular channels has been synthesized and structurally characterized by single‐crystal X‐ray diffraction. The high green emission intensity and the microporous nature of the Tb‐MOF indicate that it can potentially be used as a luminescent sensor. In this work, we show that Tb‐MOF can selectively sense Fe3+ and Al3+ ions from mixed metal ions in water through different detection mechanisms. In addition, it also exhibits high sensitivity for 2,4,6‐trinitrophenol (TNP) in the presence of other nitro aromatic compounds in aqueous solution by luminescence quenching experiments.  相似文献   

10.
The open‐chain polyether‐bridged flexible ligand 1,2‐bis[2‐(1H‐1,3‐imidazol‐1‐ylmethyl)phenoxy]ethane (L) has been used to create two two‐dimensional coordination polymers under hydrothermal reaction of L with CdII or CoII, in the presence of benzene‐1,4‐dicarboxylic acid (H2bdc). In poly[[(μ2‐benzene‐1,4‐dicarboxylato){μ‐1,2‐bis[2‐(1H‐1,3‐imidazol‐1‐ylmethyl)phenoxy]ethane}cadmium(II)] dihydrate], {[Cd(C8H4O4)(C22H22N4O2)]·2H2O}n, (I), and the cobalt(II) analogue {[Co(C8H4O4)(C22H22N4O2)]·2H2O}n, (II), the CdII and CoII cations are six‐coordinated by four carboxylate O atoms from two different bdc2− dianions in a chelating mode and two N atoms from two distinct L ligands. The metal ions, bdc2− dianions and L ligands each sit across crystallographic twofold axes. The bdc2− coordination mode and the coordinating orientation of the L ligand play an important role in constructing the novel two‐dimensional framework. Complexes (I) and (II) are threefold interpenetrated two‐dimensional frameworks; their structures are almost isomorphous, while the bond lengths, angles and hydrogen bonds are different in (I) and (II).  相似文献   

11.
A combination of a bent bis(naphthalene) and hydroxy‐based dicarboxylate linker and a flexible bis(tridentate)polypyridyl ligand has been employed to self‐assemble with two different d10 metal centers, ZnII and CdII, to form structurally diversified luminescent metal–organic frameworks, [Zn2(tpbn)(mbhna)2(H2O)2]?4 H2O?1.5DMF ( 1 ) and {[Cd2(tpbn)(mbhna)2]?2DMF}n ( 2 ), respectively (where, tpbn=N,N′,N′′,N′′′‐tetrakis(pyridine‐2‐ylmethyl)butane‐1,4‐diamine and H2mbhna=4,4′‐methylene‐bis[3‐hydroxy‐2‐naphthalene carboxylic acid]). Both 1 and 2 are characterized and analyzed by various analytical techniques including single‐crystal X‐ray diffractometry. Their excellent emissive nature is studied in different solvents and further utilized to selectively detect aromatic amines, particularly 4‐nitroaniline in water with detection limits at sub‐ppm level. The difference in sensing activity of 1 and 2 toward 4‐NA is corroborated well with their structures. The mechanism of action has been established through Stern–Volmer plot, spectral overlap, time‐resolved lifetime studies and HOMO–LUMO energy calculations. In addition, 1 and 2 are found to be recyclable and display good stability after sensing experiments.  相似文献   

12.
Solvothermal reactions of 1‐cyanobenzoimidazole, NaN3, and hydrated MIICl2 (M = Mn, Zn, Cu) in a mixture of EtOH/H2O in the presence of NH4Cl afforded a mononuclear complex [Mn(L1)2(H2O)4] ( 1 ), a 3D polymer [Zn(L1)(OH)]n ( 2 ), and a linear polymer {[Cu(Bim)]}n ( 3 ), respectively, where the ligand L1 is formed in‐situ from [3+2] dipolar cycloaddition of N3 with nitrile and the ligand Bim is in‐situ formed from C–N bond cleavage of 1‐cyanobenzoimidazole. (L1 = 5‐benzoimidazoyltetrazolate, Bim = benzoimidazole). All the compounds were characterized by IR spectroscopy, elemental analysis, and thermo‐gravimetric analysis (TGA), and their structures were determined by X‐ray crystallography. The solid state luminescent properties of 2 and 3 were also investigated at room temperature.  相似文献   

13.
The title compound, {[Cu(C14H9NO3)(C5H5N)]·C3H7NO}n or {[Cu2L2(py)2]·2DMF}n [py is pyridine, L is 4‐(salicylideneamino)benzoate and DMF is dimethylformamide], is composed of dimeric dicopper [CuL(py)]2 building units, which are interlinked into a one‐dimensional chain through the formation of Cu—OCOO bonds. The dimeric unit is centrosymmetric, containing two CuII atoms linked by bridging phenolate O atoms into a Cu2O2 plane with a chelating Cu—O bond length of 1.927 (2) Å and a bridging Cu—O bond length of 2.440 (2) Å. Interchain C—H...O and π–π stacking interactions are responsible for an extensive three‐dimensional structure in which the resulting channels are filled by DMF solvent molecules.  相似文献   

14.
Three new complexes {[Cu( L1 )2(NO3)2]?H2O}oo ( 1 ), {[Cu4( L2 )2(OAc)8]‐CH3CH2OH}oo ( 2 ) and [Cd2( L3 )3(NO3)4(H2O)2]oo ( 3 ) ( L1= 4‐phenyl‐7‐(pyridine‐3‐yl)‐1,2,4‐triazolo[3,4‐b]‐1,3,4‐thiadiazole, L2= 4‐(pyridine‐3‐yl)‐7‐phenyl‐1,2,4‐triazolo[3,4‐b]‐1,3,4‐thiadiazole, and L3= 4‐(pyridine‐4‐yl)‐7‐phenyl‐1,2,4‐triazolo[3,4‐b]‐1,3,4‐thiadiazole) have been synthesized and characterized by elemental analyses, IR spectra and single crystal X‐ray diffraction. The structural analyses reveal that complex 1 is a neutral 2‐D network structure with a 44 topology, 2 has a 1‐D neutral coordination chain with a [Cu2(CH3COO)4] dinuclear structural unit bridged by four acetate ions, and 3 is a neutral rhombohedral grid structure. All the complexes are air stable at room temperature. Furthermore, the fluorescent properties of complex 3 and corresponding ligand L3 have been investigated and discussed.  相似文献   

15.
Investigating the coordination chemistry of H2CDA (4‐oxo‐1,4‐dihydro‐2,6‐pyridinedicarboxylic acid) with rare earth salts Ln(NO3)3 under hydrothermal conditions, structure transformation phenomenon was observed. The ligand, H2CDA charged to its position isomer, enol type structure, H3CAM (4‐hydroxypyridine‐2,6‐dicarboxylic acid). Six new lanthanide(III) coordination polymers with the formulas [Ln(CAM)(H2O)3]n [Ln = La ( 1 ), Pr, ( 2 )] and {[Ln(CAM)(H2O)3] · H2O}n [Ln = Nd, ( 3 ), Sm, ( 4 ), Eu, ( 5 ), Y, ( 6 )] were synthesized and characterized. The X‐ray structure analyses show two kinds of coordination structures. The complexes 1 and 2 and 3 – 6 are isostructural. Complexes 1 and 2 crystallize in the monoclinic C2/c space group, whereas 3 – 6 crystallize in the monoclinic system with space group P21/n. In the two kinds of structures, H3CAM displays two different coordination modes. The SmIII and EuIII complexes exhibit the corresponding characteristic luminescence in the visible region at an excitation of 376 nm.  相似文献   

16.
Two complexes based on the ligand 1,4‐dihydro‐2,3‐quinoxalinedione, namely [Mn(H2L)2(H2O)2]n ( 1 ) and {[Zn2(H2L)2(tz)2] · 5H2O}n ( 2 ) (H3L = 2,3‐dioxo‐1,2,3,4‐tetrahydroquinoxaline‐6‐carboxylic acid, Htz = 1,2,4‐triazole) were hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, as well as single‐crystal and powder X‐ray diffraction. Complex 1 exhibited a 1D comb‐like chain formed by H2L anions linking MnII ions, whereas complex 2 was a 2D layer‐like structure with square‐shaped windows and outstretched arms built by combination of H2L and tz ligands with ZnII ions. The adjacent chains or layers connected with each other by intermolecular hydrogen bonding and π–π stacking to further extend to a 3D supermolecular framework. In addition, the thermal stabilities, luminescence properties, and optical energy gap of 1 and 2 were investigated in detail.  相似文献   

17.
The ultrasonic reaction of AgNO3, 4,4′‐bipyridine (bipy) and naphthalene‐2,6‐dicarboxylic acid (H2NDC) gives rise to the title compound, {[Ag2(C10H8N2)2](C12H6O4)·4H2O}n. The NDC dianion is located on an inversion centre. The AgI centre is coordinated in a linear manner by two N atoms from two bipy ligands. The crystal structure consists of one‐dimensional AgI–bipy cationic chains and two‐dimensional NDC–H2O anionic sheets, constructed by coordination bonds and supramolecular interactions, respectively.  相似文献   

18.
We report here the synthesis, structure, magnetic and photoluminescent properties of three new bifunctional Schiff‐base complexes [Dy(L1)2(py)2][B(Ph)4]?py ( 1 ), [Dy(L1)2Cl(DME)] ? 0.5DME ( 2 ) and [Dy(L2)2Cl] ? 2.5(C7H8) ( 3 ) (HL1=Phenol, 2,4‐bis(1,1‐dimethylethyl)‐6‐[[(2‐methoxy‐5‐methylphenyl)imino]methyl]; HL2=Phenol, 2,4‐bis(1,1‐dimethylethyl)‐6‐[[(2‐methoxyphenyl)imino]methyl]). The coordination environment of the Dy3+ ion and the direction of the anisotropic axis may be controlled by the combination of the substituent groups of the Schiff bases, the nature of the counter‐ions (Cl? vs. BPh4?) and the coordinative solvent molecules. A zero‐field slow relaxation of the magnetization is evidenced for all complexes but strong differences in the relaxation dynamics are observed depending on the Dy3+ site geometry. In this sense, complex 1 exhibits an anisotropy barrier of 472 cm?1, which may be favourably compared to other related examples due to the shortening of the Dy?O bond in the axial direction. Besides, the three complexes exhibit a ligand‐based luminescence making them as bifunctional magneto‐luminescent systems.  相似文献   

19.
Three 1H‐benzimidazole‐5‐carboxylate (Hbic)‐based coordination polymers, {[Ni(H2O)(Hbic)2] · 2H2O}n ( 1 ), {[Ni(H2O)2(Hbic)2] · 3H2O}n ( 2 ), and {[Co2(H2O)4(Hbic)4] · 4DMF · 3H2O}n ( 3 ) were obtained by reactions of the ligand H2bic and NiII or CoII salts in the presence of different structure directing molecules. They were structurally characterized by single‐crystal X‐ray diffraction, IR spectra, elemental analysis, thermal stability, luminescent, and magnetic measurements. Structural analysis suggests that the three polymers exhibit a 2D (4, 4) layer for 1 and 1D linear double chains for both 2 and 3 due to the variable binding modes and the specific spatial orientation of the Hbic ligand towards the different paramagnetic metal ions, which were further aggregated into different 3D supramolecular architectures by popular hydrogen‐bonding interactions. Weak and comparable antiferromagnetic couplings mediating by Hbic bridge are observed between the neighboring spin carriers for 2 and 3 , respectively. Additionally, complexes 1 – 3 also display different luminescence emissions at room temperature due to the ligand‐to‐metal charge transfer.  相似文献   

20.
The title complex, {[Ni(C15H11N4O2S)2(C10H8N2)(H2O)2]·H2O}n, was synthesized by the reaction of nickel chloride, 4‐{[(1‐phenyl‐1H‐tetrazol‐5‐yl)sulfanyl]methyl}benzoic acid (HL) and 4,4′‐bipyridine (bpy) under hydrothermal conditions. The asymmetric unit contains two half NiII ions, each located on an inversion centre, two L ligands, one bpy ligand, two coordinated water molecules and one unligated water molecule. Each NiII centre is six‐coordinated by two monodentate carboxylate O atoms from two different L ligands, two pyridine N atoms from two different bpy ligands and two terminal water molecules, displaying a nearly ideal octahedral geometry. The NiII ions are bridged by 4,4′‐bipyridine ligands to afford a linear array, with an Ni...Ni separation of 11.361 (1) Å, which is further decorated by two monodentate L ligands trans to each other, resulting in a one‐dimensional fishbone‐like chain structure. These one‐dimensional fishbone‐like chains are further linked by O—H...O, O—H...N and C—H...O hydrogen bonds and π–π stacking interactions to form a three‐dimensional supramolecular architecture. The thermal stability of the title complex was investigated via thermogravimetric analysis.  相似文献   

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