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1.
Three novel zinc complexes [Zn(dbsf)(H2O)2] ( 1 ), [Zn(dbsf)(2,2′‐bpy)(H2O)]·(i‐C3H7OH) ( 2 ) and [Zn(dbsf)(DMF)] ( 3 ) (H2dbsf = 4,4′‐dicarboxybiphenyl sulfone, 2,2′‐bpy = 2,2′‐bipyridine, i‐C3H7OH = iso‐propanol, DMF = N,N‐dimethylformamide) were first obtained and characterized by single crystal X‐ray crystallography. Although the results show that all the complexes 1–3 have one‐dimensional chains formed via coordination bonds, unique three‐dimensional supramolecular structures are formed due to different coordination modes and configuration of the dbsf2? ligand, hydrogen bonds and π–π interactions. Iso‐propanol molecules are in open channels of 2 while larger empty channels are formed in 3 . As compared with emission band of the free H2dbsf ligand, emission peaks of the complexes 1–3 are red‐shifted, and they show blue emission, which originates from enlarging conjugation upon coordination. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

2.
Two coordination polymers, {[Zn2(L)(bpy)] · 2H2O}n ( 1 ) and [Zn2(L)(bpe)]n ( 2 ) [H4L = terphenyl‐2,2′,4,4′‐tetracarboxylic acid, bpy = 4,4′‐bipyridine, and bpe = 1,2‐bis(4‐pyridyl)ethane], were hydrothermally synthesized under similar conditions and characterized by elemental analysis, IR spectroscopy, TGA, and single‐crystal X‐ray diffraction analysis. Compound 1 has a 3D framework containing Zn–O–C–O–Zn 1D chains. Compound 2 exhibits a 3D framework, which features tubular channels. The channels are occupied by bpe molecules. The differences in the structures demonstrate that the auxiliary dipyridyl‐containing ligand has a significant effect on the construction of the final framework. Additionally, the fluorescent properties of the two compounds were also studied in the solid state at room temperature.  相似文献   

3.
First examples of transition metal complexes with HpicOH [Cu(picOH)2(H2O)2] ( 1 ), [Cu(picO)(2,2′‐bpy)]·2H2O ( 2 ), [Cu(picO)(4,4′‐bpy)0.5(H2O)]n ( 3 ), and [Cu(picO)(bpe)0.5(H2O)]n ( 4 ) (HpicOH = 6‐hydroxy‐picolinic acid; 2,2′‐bpy = 2,2′‐bipyridine; 4,4′‐bpy = 4,4′‐bipyridine; bpe = 1,2‐bis(4‐pyridyl)ethane) have been synthesized and characterized by single‐crystal X‐ray diffraction. The results show that HpicOH ligand can be in the enol or ketonic form, and adopts different coordination modes under different pH value of the reaction mixture. In complex 1 , HpicOH ligand is in the enol form and adopts a bidentate mode. While in complexes 2 – 4 , as the pH rises, HpicOH ligand becomes in the ketonic form and adopts a tridentate mode. The coordination modes in complexes 1 – 4 have not been reported before. Because of the introduction of the terminal ligands 2,2′‐bpy, complex 2 is of binuclear species; whereas in complexes 3 and 4 , picO ligands together with bridging ligands 4,4′‐bpy and bpe connect CuII ions to form 2D nets with (123)2(12)3 topology.  相似文献   

4.
The reaction of (Z)‐2‐[amino(pyridine‐2‐yl)methylene]hydrazonecarbothioamide (HAm4DH) with Mn(ClO4)2·6H2O afforded different mononuclear or polynuclear manganese(II) complexes, the nature of which apparently depended on the solvent used. For example, in ethanol a compound of formula [Mn(HAm4DH)2](ClO4)2 ( 1 ) was obtained, where HAm4DH coordinates as a common tridentate NNS donor, but the [Mn(bpy)2(NCS)2] complex ( 2 ) (bpy = 2,2'‐bipyridine) has also been obtained – probably due to C–N bond cleavage of the thiosemicarbazone. Nevertheless, in a basic aqueous medium [Mn(bpy)3](ClO4)2·0.5bpy ( 3 ) is formed and there is structural evidence for chemical transformations of the thiosemicarbazone promoted by MnII. Thus, the sulfate in {[Mn(py)4Mn(py)2(H2O)2(μ‐SO4)2]·4H2O}n ( 4 ) or sulfate and cyclooctasulfur in [Mn(pta)2(pdo)]4(SO4)2·4H2O·S8] ( 5 ), where pta is 3‐(pyridin‐2‐yl)‐1,2,4‐triazol‐5‐amine and pdo is (2R,4R/2S,4S)‐pentane‐2,4‐diolato, arise from the desulfuration and oxidation of the thiosemicarbazone ligand. The structures of complexes 2 to 5 were established by single‐crystal X‐ray diffraction. The formation of pta is the result of the oxidative cyclization of HAm4DH. In the polynuclear complex 4 , the sulfate acts as an (O,O') bridge between alternating Mn(py)2(H2O)2 and Mn(py)4 centers. In the tetranuclear complex 5 , pta acts as a bischelating ligand through the N‐pyridine and N‐triazole, and pdo act as a bridge between two manganese atoms. It is also noteworthy that in complexes 4 and 5 hydrogen bonds give rise to different self‐assembly behaviour that leads to complicated supramolecular structures.  相似文献   

5.
Four new transitional metal supramolecular architectures, [Zn(cca)(2,2′‐bpy)]n · n(2,2′‐bpy) ( 1 ), [Cu(cca)(2,2′‐bpy)]n ( 2 ), [Zn(bpdc)(2,2′‐bpy)(H2O)]n · 0.5nDMF · 1.5nH2O ( 3 ), and [Co(bpdc)(2,2′‐bpy)(H2O)]n · nH2O ( 4 ) (H2cca = p‐carboxycinnamic acid; H2bpdc = 4,4′‐biphenyldicarboxylic acid; 2,2′‐bpy = 2,2′‐bipyridine) were synthesized by hydrothermal reactions and characterized by single crystal X‐ray diffraction, elemental analyses, and IR spectroscopy. Although the metal ions in these four compounds are bridged by linear dicarboxylic acid into 1D infinite chains, there are different π–π stacking interactions between the chains, which results in the formation of different 3D supramolecular networks. Compound 1 is of a 3D open‐framework with free 2,2′‐bpy molecules in the channels, whereas compound 2 is of a complicated 3D supramolecular network. Compounds 3 and 4 are isostructural. Both compounds have open‐frameworks.  相似文献   

6.
Two new coordination polymers, {[Cd2(btc)(2,2′‐bpy)2] · H2O}n ( 1 ) and [Zn2(btc)(2,2′‐bpy)(H2O)]n ( 2 ) (H4btc = biphenyl‐2,2′,4,4′‐tetracarboxylic acid, 2,2′‐bpy = 2,2′‐bipyridine), were synthesized hydrothermally under similar conditions and characterized by elemental analysis, IR spectra, TGA, and single‐crystal X‐ray diffraction analysis. In complexes 1 and 2 , the (btc)4– ligand acts as connectors to link metal ions to give a 2D bilayer network of 1 and a 3D metal‐organic framework of 2 , respectively. The differences in the structures are induced by diverging coordination modes of the (btc)4– ligand, which can be attributed to the difference metal ions in sizes. The results indicate that metal ions have significant effects on the formation and structures of the final complexes. Additionally, the fluorescent properties of the two complexes were also studied in the solid state at room temperature.  相似文献   

7.
Three coordination compounds [Mn3(dmb)6(H2O)4(4, 4′‐bpy)3(EtOH)]n ( 1 ) and [M(dmb)2(pyz)2 (H2O)2] [MII = Co ( 2 ), Mn ( 3 )] (Hdmb = 2, 6‐dimethoxybenzoic acid, 4, 4′‐bpy = 4, 4′‐bipyridine, pyz = pyrazine) were synthesized and characterized by single‐crystal X‐ray diffraction analysis. Compound 1 consists of infinite 1D polymeric chains, in which the metal entities are bridged by 4, 4′‐bpy ligands. There are four crystallographically independent MnII atoms in the linear chain with different coordination modes, which is only scarcely reported for linear polymers. The isostructural crystals of 2 and 3 are composed of neutral mononuclear complexes. In crystal the complexes are combined into chains by intermolecular O–H ··· N hydrogen bonds and π–π interactions between antiparallel pyrazine molecules.  相似文献   

8.
Two new nickel(II) complexes, [Ni(4, 4′‐bpy)(H2O)4]n · n(cpp) · 0.5nH2O ( 1 ) and [Ni(cpp)(4, 4′‐bpy)(H2O)2]n ( 2 ) [4, 4′‐bpy = 4, 4′‐bipyridine, H2cpp = 3‐(4‐carboxyphenyl)propionic acid] were synthesized and characterized by single‐crystal X‐ray diffraction, elemental analysis, IR spectroscopy, and thermal analysis. In complex 1 , NiII ions are bridged by 4, 4′‐bpy into 1D chains, and cpp ligands are not involved in the coordination, whereas in complex 2 , cpp ligands adopt a bis(monodentate) mode and link NiII ions into 2D (4, 4) grids with the help of 4, 4′‐bpy ligands. Triple interpenetration occurs, which results in the formation of a complicated 3D network. The difference in the structures of the two complexes can be attributed to the different reaction temperatures and bases.  相似文献   

9.
Two nitrilotriacetate cobalt complexes {[CoK2(NTA)(Hmta)(H2O)3]NO3}n ( 1 ) and [{Co(4,4′‐bpy)2(H2O)4}{Co2(NTA)2(4,4′‐bpy)(H2O)2}] ( 2 ) (NTA = nitrilotriacetate anion, Hmta = hexamethylenetetramine and 4,4′‐bpy = 4,4′‐bipyridine) were prepared and characterized by IR, elemental analysis and single crystal X‐ray diffraction study. The influence of the neutral ancillary ligands on the formation of the complexes with different structures in the Co‐NTA system was discussed. The coordination of NTA and Hmta to Co2+ ions only resulted in the formation of mononuclear [Co(NTA)(Hmta)]? ions which are further connected by K+ ions and water molecules to form a three‐dimensional network. The use of 4,4′‐bpy as ancillary ligand in 2 led to the formation of separate mononuclear [Co(4,4′‐bpy)2(H2O)4]2+ and dinuclear [Co2(NTA)2(4,4′‐bpy)(H2O)2]2? which are further connected by hydrogen bonds to form a supramolecular three‐dimensional network. In these cases it seems to suggest that the addition of neutral ancillary ligand into the Co‐NTA system leads to the formation of lower dimensional structures when the contribution of alkali ions to the structural dimensionality is neglected.  相似文献   

10.
Taking Ni(2‐mpac)2(H2O)2 as molecular building block, two novel coordination polymers with the formula of [Ni(2‐mpac)2(4,4′‐bpy)·(4,4′‐bpy)]n ( 1 ) and [Ni(2‐mpac)2(py)·4H2O]n ( 2 ) (2‐mpac = 5‐methyl‐2‐pyrazinecarboxylic acid; 4,4′‐bpy = 4,4′‐bipyridine; py = pyrazine) have been synthesized and structurally characterized by X‐ray single crystal diffraction method. In addition, elemental analysis, IR and magnetism characterization are presented.  相似文献   

11.
Yellow crystals of [Mn(H2O)2(bpy)(C4H4O4)] · H2O were obtained by the reaction of 2,2′‐bipyridine, succinic acid, MnSO4 · H2O and Na2CO3 in an aqueous methanol solution. The crystal structure (monoclinic, P21/c (no. 14), a = 8.294(1), b = 11.556(1), c = 17.064(1)Å, β = 95.181(6)°, Z = 4, R = 0.0349, wR2 = 0.0887) consists of 1D supramolecular helix chains [Mn(H2O)2(bpy)(C4H4O4)2/2] and hydrogen bonded H2O molecules. The Mn atoms are octahedrally coordinated by two N atoms of one bidentate chelating bpy ligand and four O atoms of two H2O molecules and two bis‐monodentate bridging succinato ligands with d(Mn–O) = 2.139–2.237Å and d(Mn–N) = 2.268, 2.281 Å. The helix chains are held together by π‐π stacking interactions and hydrogen bonds.  相似文献   

12.
Reaction of MnSO4 · H2O, 2,2′‐bipyridine (bpy), suberic acid and Na2CO3 in CH3OH/H2O yielded a mixture of [Mn2(H2O)4(bpy)2(C8H12O4)2] · 2 H2O ( 1 ) and [Mn(H2O)2‐ (bpy)(C8H12O4)2/2] · H2O ( 2 ). In both complexes, the Mn atoms are octahedrally coordinated by two N atoms of one bpy ligand and four O atoms of two trans positioned H2O molecules and two suberato ligands (d(Mn–O) = 2.107–2.328 Å; d(Mn–N) = 2.250–2.330 Å). The bis‐monodentate suberato ligands bridge Mn atoms to form dinuclear [Mn2(H2O)4(bpy)2(C8H12O4)2] complex molecules in 1 and 1D [Mn(H2O)2(bpy)(C8H12O4)2/2] chains in 2 . Via the intermolecular hydrogen bondings and π‐π stacking interactions, the dinuclear molecules in 1 are assembled into 2D networks parallel to (100), between which the crystal H2O molecules are sandwiched. The polymeric chains in 2 are linked together by interchain hydrogen bonding and π‐π stacking interactions into 3D networks with the crystal H2O molecules located in tunnels along [010]. Crystal data for 1 : P21/c (no. 14), a = 10.092(1) Å, b = 11.916(2) Å, c = 17.296(2) Å, β = 93.41(1)° and Z = 2. Crystal data for 2 : P21/c (no. 14), a = 11.176(2) Å, b = 9.688(1) Å, c = 37.842(6) Å, β = 90.06(1)° and Z = 8.  相似文献   

13.
The hydrothermal reactions of Ni(II), 1,2,3‐benzenetricarboxylic acid (1,2,3‐H3btc) and 4,4′‐bipyridine (4,4′‐bpy)/1,2‐bis(4‐pyridyl)ethane (bpa) yield two layered nickel(II) coordination polymers, [Ni2(1,2,3‐btc)(OAc)‐(4,4′‐bpy)2(H2O)]·2H2O ( 1 ) and [Ni(ip)(bpa)] ( 2 ) (ip=isophthalate), respectively. Both complexes are 2‐D coordination network based on 1‐D Ni‐carboxylate chains. The 1,2,3‐btc ligand adopts 3‐bridging mode in complex 1 , but transformed to isophthalate (ip) ligand through decarboxylation in 2 . The formation of the two complexes indicates that hydrothermal conditions andin‐situ ligand reaction have significant effect on constructing coordination polymers.  相似文献   

14.
Three ZnII and CdII complexes with Y‐shaped dicarboxylate ligands, namely [Zn(L1)(2,2′‐bpy)2(H2O)] · 2H2O ( 1 ), [Zn(L1)(bpp)(H2O)] ( 2 ), and [Cd(L1)(H2O)] · H2O ( 3 ) [H2L1 = N‐phenyliminodiacetic acid, 2,2′‐bpy = 2,2′‐bipyridine, bpp = 1,3‐bis(4‐pyridyl)propane] were synthesized and characterized by elemental analysis, IR spectroscopy single‐crystal X‐ray diffraction, and thermogravimetric analyses. Compound 1 shows an hydrogen‐bonded 2D network, whereas compound 2 is an infinite 1D wavy chain structure, though O–H ··· O hydrogen‐bonded to form a 2D network. Compound 3 displays a 2D uninodal 3‐connected Shubnikov plane net with the point symbol of (4.82). Moreover, the solid‐state such as thermal stabilities and fluorescence properties of 1 – 3 were also investigated.  相似文献   

15.
The β‐diketonate derivative ligand [H2L = 6‐(3‐hydroxy‐1‐oxo‐3‐pyrryl‐2‐propen‐1‐yl)‐2‐pyridinecarboxylic acid] and its zinc(II) coordination complexes, [Zn(H2L)Cl2] · (EtOH)(H2O) ( 1 ) and [Zn4(L)4(H2O)2] · 5H2O ( 2 ), were prepared and characterized by elemental analysis, IR and NMR spectroscopy, and single‐crystal X‐ray diffraction. Complex 1 is a mononuclear structure. Complex 2 is a [2 × 2] grid tetranuclear structure. The luminescent properties of the free ligand H2L and complexes 1 and 2 in methanol solution were studied.  相似文献   

16.
A new polynuclear copper‐complex‐substituted dimeric tungstoarsenate(V), H2[{Cu(2,2′‐bpy)}8(H2O)2(AsW9O34)2] · 12H2O ( 1 ) (2,2′‐bpy = 2,2′‐bipydine), was synthesized hydrothermally and its structure was determined by single‐crystal X‐ray diffraction. The title compound has Ci symmetry and consists of two trilacunary Keggin anions [α‐AsW9O34]9– supported by eight copper complex cations. The compound was also characterized by IR and fluorescence spectroscopy, TG analysis, and magnetic measurements. The emission spectrum of the compound in solid‐state exhibits a redshift relative to those of Na8[A‐HAsW9O34] · 11H2O and the free ligand 2,2′‐bpy. Magnetic measurements of the compound indicate competing ferro‐ and antiferromagnetic intramolecular coupling among the CuII atoms in the cluster anion.  相似文献   

17.
Solvothermal reaction of Zn(NO3)2 ? 4 H2O, 1,4‐bis[2‐(4‐pyridyl)ethenyl]benzene (bpeb) and 4,4′‐oxybisbenzoic acid (H2obc) in the presence of dimethylacetamide (DMA) as one of the solvents yielded a threefold interpenetrated pillared‐layer porous coordination polymer with pcu topology, [Zn2(bpeb)(obc)2] ? 5 H2O ( 1 ), which comprised an unusual isomer of the well‐known paddle‐wheel building block and the transtranstrans isomer of the bpeb pillar ligand. When dimethylformamide (DMF) was used instead of DMA, a supramolecular isomer [Zn2(bpeb)(obc)2] ? 2 DMF ? H2O ( 2 ), with the transcistrans isomer of the bpeb ligand with a slightly different variation of the paddle‐wheel repeating unit, was isolated. In MeOH, single crystals of 2 were transformed by solvent exchange in a single‐crystal‐to‐single‐crystal (SCSC) manner to yield [Zn2(bpeb)(obc)2] ? 2 H2O ( 3 ), which is a polymorph of 1 . SCSC conversion of 3 to 2 was achieved by soaking 3 in DMF. Compounds 1 and 2 as well as 2 and 3 are supramolecular isomers.  相似文献   

18.
Self‐assembly reaction between hydrated rare‐earth (RE) nitrates RE(NO3)3 · 6H2O with K3Fe(CN)6 in H2O/DMF solution by employing the tridentate ligand 2, 2′:6′,2′′‐terpyridine (terpy) as a capping ligand has yielded three cyanide‐bridged compounds [RE(terpy)(DMF)(H2O)2][Fe(CN)6] · 6H2O [RE = Y ( 1 ), Tb ( 2 ), Dy ( 3 )]. FT‐IR spectra confirmed the presence of terpy ligands and cyanide groups in compounds 1 – 3 . Single‐crystal X‐ray structural analysis indicated that these compounds are isomorphous and adopt neutral [RE2Fe2] molecular squares, which are further linked through hydrogen bonding interactions to generate a three‐dimensional supramolecular network. Magnetic susceptibility measurements revealed that significant single ion magnetic anisotropy dominates the properties of these compounds.  相似文献   

19.
The europium complex [EuCl2(bpy)2(H2O)2]Cl?1.25 C2H6O?0.37 H2O, where bpy is 2,2′‐bipyridine, was synthesized and investigated with the aim to relate its molecular geometry and crystal packing to the efficiency of energy‐transfer processes. The presence of H‐bonds between noncoordinated Cl? ions and coordinated H2O molecules leads to the formation of discrete trimers assembled by a number of C? H???Cl and stacking interactions into ‘supramolecular balls’ which contain Cl? ions and solvate molecules (H2O and EtOH). The additional stabilization of the complex is due to intramolecular N???C interactions between two bpy ligands that causes some shortening of the Eu? N bonds. Deciphering the luminescence properties of the Eu complex was performed under consideration of both the composition of the inner coordination sphere and the peculiarities of the crystal packing. The influence of the latter and the bpy orientation on the energy of the ligand→Eu charge‐transfer state (LMCT) was established, and an additional excited state induced by the π‐stacking interaction (SICT) was identified.  相似文献   

20.
Two coordination polymers, namely Zn(HL)(4,4′‐bpy)1.5 ( 1 ), [Zn3(L)2(BIMB)2] · 5H2O ( 2 ) [H3L = 5‐(4‐carboxybenzyloxy)isophthalic acid, 4,4′‐bpy = 4,4′‐bipyridine, BIMB = 1,4‐bis(1H‐imidazol‐1‐yl)benzene] were synthesized under hydrothermal conditions. Their structures are determined by single‐crystal X‐ray diffraction analyses and further characterized by elemental analyses, IR spectroscopy, and thermogravimetric (TG) analyses. Complex 1 features a 2D 4‐connected network. Complex 2 is a 3D twofold interpenetrating (3,4,6)‐connected net. In addition, the luminescent properties for 1 and 2 were studied in the solid state at room temperature.  相似文献   

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