Assembly,crystal structures,and luminescent properties of three new thiocyanate-bridging mercury(II) coordination polymers

Two ligands, 2-{5,5-dimethyl-3-[2-(pyridin-3-yl)-ethenyl]cyclohex-2-enylidene}propanedinitrile (L1) and 2-{5,5-dimethyl-3-[2-(pyridin-2-yl)-ethenyl]cyclohex-2-enylidene}propanedinitrile (L2), were synthesized. By reaction of mercury thiocyanate with L1 and L2, respectively, coordination polymers [Hg(L1)(μ_1,3-SCN)₂]_n (1), [Hg(L1)₂(μ_1,3-SCN)₂]_n (2), and [Hg(L2)(μ_1,3-SCN)(SCN)]_n (3) with different structures and topologies were obtained. In 1, the thiocyanate shows μ_1,3-SCN bridging coordination, and adjacent Hg(II) ions are bridged by two μ_1,3-SCN ions to form an infinite chain with the remaining position of five-coordinate Hg(II) occupied by L1. In 2, the thiocyanate has the same coordination as 1. However, Hg(II) has octahedral coordination with two L1 involved in coordination. An unusual feature of 3 is the presence of two types of thiocyanates, one has a S-terminal ligand and the other has a μ_1,3-SCN bridge. The mercury(II) in 3 is four-coordinated by L2 and three thiocyanates. Luminescent properties and thermal stabilities of 1–3 were studied.     

A twofold interpenetrated 3-D Cu(II) coordination polymer based on 5-(pyridin-4-yl)isophthalic acid: synthesis,crystal structure,and magnetic properties

A new copper(II) coordination polymer, [Cu(PIA)·2H₂O]_n (1) [H₂PIA = 5-(pyridin-4-yl)isophthalic acid], has been synthesized and characterized by elemental analysis, IR spectroscopy, TGA, powder, and single-crystal X-ray diffraction. Structural analysis shows that each PIA^2? in 1 bridges three Cu(II) ions, and likewise each Cu(II) ion connects to three PIA^2? ligands, giving a 3-D framework with utp topology and left-/right-handed helical channels. Interestingly, two such identical frameworks interlock with each other to generate a twofold interpenetrated structure that is stabilized by hydrogen bonding and π–π interactions. In addition, the thermal stability and the magnetic properties of 1 have been investigated.     

Four distinctive 1-D lanthanide carboxylate coordination polymers: Synthesis,crystal structures and spectral properties

Four novel lanthanide coordination polymers [Pr(mal)(OH)(bipy) · 2H₂O]_n (1), {[Dy¹(SBA)₃(H₂O)₂][Dy²(SBA)₃(H₂O)₂] · 4H₂O}_n (2), {[Tb(OHnic)(Onic)(H₂O)₅ · (OHnicH)] · H₂O}_n (3) and {[Sm(OHnic)(Onic)(H₂O)₅ · (OHnicH)] · H₂O}_n (4) (Hmal = maleic acid, HSBA = 4-sulfobenzoic acid, OHnicH = 6-hydroxynicotinic acid and bipy = 2,2′-bipyridine) have been synthesized and determined by single crystal X-ray diffraction. Complex 1 is a 1-D helical chain with seven-coordinated praseodymium centers. Complex 2 forms 1-D chain-like molecular structure containing two crystallographically unique dysprosium centers, the Dy¹ center is seven-coordinated while Dy² is eight-coordinated. The isomorphous complexes 3 and 4 exhibit an unprecedented 1-D chain-like polymeric structure through hydroxyl oxygen atoms of bridging Onic²⁻ anions linking up the neighboring central ions, and there exist three types of 6-OHnicH ligands in the structural unit which is rare for lanthanide carboxylate complexes. The photophysical properties of these complexes were studied using ultraviolet absorption spectra, fluorescence excitation and emission spectra.     

Synthesis, structure and luminescent properties of rare earth coordination polymers constructed from paddle-wheel building blocks

A series of three-dimensional (3D) novel coordination polymers M(bpdc)1.5(H2O) x 0.5DMF (M = Tb (1), Ho (2), Er (3), or Y (4)) have been synthesized by reaction of the rare earth ions (M3+) with 4,4'-biphenyldicarboxylic acid (H2bpdc) in a mixed solution of DMF and C2H5OH. They possess the same 3D architectures and crystallize in monoclinic space group C2/c. Two seven-coordinated metal centers and four dimonodentate bpdc groups construct a paddle-wheel building block. These building blocks connect with two carboxyl groups to lead to a one-dimensional inorganic chain, ---M-O-C-O-M---, along the [001] direction. The inorganic chains are linked with two biphenyl groups to form 25.15 A x 17.09 A rhombic channels along the c axis without interpenetration. These complexes exhibit strong fluorescence in the visible region, and complex 3 shows Er3+ characteristic emission in the range of 1450-1650 nm at room temperature. These complexes could be anticipated as potential fluorescent probes and an IR-emitter, respectively.     

Synthesis, structure, and magnetic properties of two 1-D helical coordination polymeric Cu(II) complexes

Two helical coordination polymeric copper(II) complexes bearing amino acid Schiff bases HL or HL′, which are condensed from 2-hydroxy-1-naphthaldehyde with 2-aminobenzoic acid or l-valine, respectively, have been prepared and characterised by X-ray crystallography. In [CuL]_n (1) the copper(II) atoms are bridged by syn-anti carboxylate groups giving infinite 1-D right-handed helical chains which are further connected by weak C-H?Cu interactions to build a 2-D network. While in [CuL′]_n (2) the carboxylate group acts as a rare monatomic bridge to connect the adjacent copper(II) atoms leading to the formation of a left-handed helical chain. Magnetic susceptibility measurements indicate that 1 exhibits weak ferromagnetic interactions whereas an antiferromagnetic coupling is established for 2. The magnetic behavior can be satisfactorily explained on the basis of the structural data.     

Synthesis,crystal structure,and electrochemical properties of Cu(I) coordination polymers with two new (NS)2 Schiff-base ligands containing long flexible spacers

Two new (NS)₂ Schiff bases, (4-NO₂Ph)₂dapte (N,N′-di-(4-nitrobenzaldimine)-1,2-di(o-aminophenylthio)ethane) (1) and (thio)₂daptx (N,N′-di-(thiophenedimine)-1,4-di(o-aminophenylthio)xylene) (2), and their 1-D copper(I) coordination polymers [Cu₂(μ-Br)₂(μ-(4-NO₂Ph)₂dapte)] _n (3), [Cu₂(μ-I)₂(μ-(4-NO₂Ph)₂dapte)] _n (4), and [Cu₂(μ-I)₂(μ-(thio)₂daptx)] _n (5) have been synthesized and characterized by elemental analyses and IR, UV-Vis, and ¹H NMR spectroscopy. The structures of 4 and 5 have been determined by X-ray crystallography and were shown to consist of Cu₂(μ-I)₂ secondary building units (SBUs) bridged by (4-NO₂Ph)₂dapte or (thio)₂daptx ligands. The CuNSI₂ coordination sphere is a distorted tetrahedral in both cases. Both (4-NO₂Ph)₂dapte and (thio)₂daptx are N₂S₂-bis-bidentate chelating ligands with the two imine nitrogens and two thioether sulfurs in a trans configuration generating dinuclear [Cu₂(μ-(4-NO₂Ph)₂dapte)] and [Cu₂(μ-(thio)₂daptx)]. These units are connected by two bridging iodides to form 1-D copper(I) coordination polymers. The electrochemical properties of 3–5 are also reported and discussed.     

Synthesis, crystal structure, and magnetic properties of two 3d-4f heterometallic coordination polymers

Two new 4f-3d heterometallic coordination polymers, [Gd₂^IIICo^II(pydc)₃(ox)(H₂O)₄)·2H₂O] (1) and [Dy^IIICu^II(pydc)₂(ox)_1/2(H₂O)₂·H₂O] (2) (pydc = pyridine-2,5-dicarboxylate anion, ox = oxalate dianion) were successfully synthesized under hydrothermal condition. Structure and magnetism of the two coordination polymers were characterized by single crystal X-ray diffraction and Quantum Design (MPMS) SQUID magnetometer. In both compounds, metal centers were connected by double ligand bridges. In 1 the gadolinium ions were linked in sheets by OCO ligand bridges and these sheets were connected by separated cobalt coordination spheres to generate the overall 2-D structure. In 2 the dysprosium centers were constructed into one dimensional chain by OCO bridges from pydc ligand bridges and these chains were linked by oxalate bridges to form sheets and different sheets were connected by copper coordination planes. The copper centers in 2 were linked in chain by elongated OCO brides and the chains were connected by hydrogen bond to generate 3-D structure. Magnetic properties of the two complexes were investigated by variable temperature magnetic susceptibility. The magnetic data suggest that overall antiferromagnetic interactions are present in the two compounds.     

N, N′, N″-(三吡啶甲酰)-三乙氨基胺与稀土硝酸盐配合物的合成、表征与荧光性质

合成了三脚架型配体N，N′，N″-(三吡啶甲酰)-三乙氨基胺(L)及其稀土硝酸盐配合物，并通过元素分析、红外光谱、核磁共振与热分析谱对它们进行表征，同时，初步研究了配体及其Eu(Ⅲ)、Tb(Ⅲ)配合物在甲醇溶液的荧光性质。     

Syntheses, structures, and magnetic properties of new rare earth coordination polymers constructed by 1,3,5-benzenetriacetic acid

Three new coordination polymers with formula [Gd(bta)(H₂O)·1.39H₂O] _n (1), [Dy(bta)(H₂O)·1.35H₂O] _n (2) and [Y(bta)(H₂O)₂·0.5H₂O] _n (3) were synthesized by using corresponding rare earth nitrates and 1,3,5-benzenetriacetic acid (H₃bta) under hydrothermal/solvothermal reaction conditions, and characterized by single-crystal X-ray diffraction. In these complexes, the carboxylate groups of bta³⁻ adopt different coordination modes, namely one carboxylate group adopts μ₂-η¹:η¹-bridging and each of the other two carboxylate groups adopts μ₂-η²:η¹-bridging coordination modes in 1 and 2, and one carboxylate group adopts a μ₂-η²:η¹-bridging coordination mode and each of the other two carboxylate groups adopts a μ₂-η¹:η¹-bridging mode for the major component and one carboxylate group adopts a μ₂-η²:η¹-bridging coordination mode, one has a μ₂-η¹:η¹-bridging mode and the third has a monodentate mode for the minor component in 3. The magnetic properties of the complexes 1 and 2 were investigated in the temperature range of 1.8–300 K.     

Synthesis, crystal structure and magnetic behavior of two cobalt coordination polymers with 1,2-bis(1,2,4-triazol-1-yl)ethane and dicyanamide

Two cobalt(II) coordination polymers formed from bte (bte = 1,2-bis(1,2,4-triazol-1-yl)ethane), namely [Co(bte)₂(dca)₂]_n (1) and {[Co(bte)(dca)₂] · H₂O}_n (2), have been synthesized and characterized by elementary analyses, IR, thermogravimetric analyses, X-ray diffraction analyses and magnetic measurements. Compound 1 is a double-chain with Co(II) centers bridged by bte, containing metallocycles of [Co₂(bte)₂] and trans dca as termination ligands. In 2, each Co(II) center is bonded by two bridging bte ligands and four dca as μ-1,5-dca in different orientations in the 3D network.     

Hydrothermal synthesis and crystal structures of two novel rare earth coordination polymers based on pyridine-2,6-dicarboxylic acid

Two novel rare earth coordination polymers, [La(pydc)₂(H₂O)][La(pydc)(H₂O)₂]·H₂O (1) and [Sm(pydc)₂(H₂O)][Sm(pydc)(H₂O)₂]·H₂O (2) (pydc=pyridine-2,6-dicarboxylate) were hydrothermally synthesized and characterized by the elemental analyses, IR spectra and TG analyses. Single crystal X-ray diffractions show that 1 and 2 are isostructural compounds. In the compounds of 1 and 2, the 1D lanthanide helical chains are connected each other by lanthanide binuclear dimer as building blocks to form a novel 3D covalent framework.     

Synthesis,crystal structure and biological properties of Cd and Zn coordination polymers based on a flexible tripodal ligand

Two new coordination polymers, namely poly[[hexathiocyanatotetrakis{μ₃‐2,4,6‐trimethyl‐1,3,5‐tris[(triazol‐1‐yl)methyl]benzene}tricadmium(II)] 3.5‐hydrate], {[Cd₃(SCN)₆(C₁₈H₂₁N₉)₄]·3.5H₂O}_n ( 1 ), and poly[[hexathiocyanatotetrakis{μ₃‐2,4,6‐trimethyl‐1,3,5‐tris[(triazol‐1‐yl)methyl]benzene}trizinc(II)] 3.5‐hydrate], {[Zn₃(SCN)₆(C₁₈H₂₁N₉)₄]·3.5H₂O}_n ( 2 ), have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectroscopy and single‐crystal X‐ray diffraction analysis. From the X‐ray analysis, it is noteworthy that polymers 1 and 2 are isostructural, with their three‐dimensional structures composed of three kinds of four‐connection metal ions and two kinds of three‐connection 2,4,6‐trimethyl‐1,3,5‐tris[(triazol‐1‐yl)methyl]benzene (TTTMB) ligand nodes. Each metal ion is six‐coordinated in a slightly distorted octahedral geometry. The antioxidant activity against DPPH (2,2‐diphenyl‐1‐picrylhydrazyl) and the antidiabetic activity against α‐amylase of the synthesized compounds were evaluated in vitro. The results of the DPPH free‐radical scavenging assay showed that polymers 1 and 2 exhibited strong antioxidant effects, with IC₅₀ values of 3.81 and 2.56 mg ml^?1, respectively. The IC₅₀ value in the antidiabetic studies of polymer 1 was 3.94 mg ml^?1, while polymer 2 exhibited no antidiabetic activity. Polymers 1 and 2 revealed different inhibitory activities on DPPH and α‐amylase, which indicated that the metal ions play important roles in the biological activity of coordination polymers. In addition, the solid‐state photoluminescence properties and thermal stability of 1 and 2 have been investigated.     

Crystal structure and fluorescence/phosphorescence of two novel Cd(II) coordination polymers

Two novel Cd(II) coordination polymers [Cd₄(C₆H₄O₂N)₈(H₂O)₄]_n (1) and [Cd₂(C₁₀H₂O₈)(H₂O)₆]_n (2) have been synthesized under hydrothermal condition and structurally characterized. Crystal data: (1), orthorhombic, Pbca, a=11.4494(19) Å, b=12.0969(6) Å, c=17.4073(8) Å, V=2410.9(4) ų, Z=8, D _calc=2.064 g·cm⁻³; (2), triclinic, P , a=5.5962(7) Å, b=7.7758(6) Å, c=9.6975(10) Å, α=111.981(5)°, β=101.649(6)°, γ=98.240(5)°, V=371.95(7) ų, Z=2, D _calc=2.603 g·cm⁻³. Complex (1) possesses three-dimensional infinite structure, while complex (2) adopts two-dimensional layers and the layers are connected by the many types of hydrogen bonds, forming three-dimensional network. Study results of the photophysical properties show that both complexes can emit strong blue fluorescence and complex (1) also emits phosphorescence (λ ^pl _max=511 nm, τ=32 ms) in the solid state at room temperature.     

几种三维镧系配位聚合物的合成、结构表征及其性质测定

在水热条件下合成了四个氨三乙酸配合物[Ln(NTA)(H2O)]n(Ln=Sm(III)、Gd(III)、Dy(III)和Er(III);NTA=氨三乙酸),分别标记为1、2、3和4;利用元素分析、红外光谱和X射线单晶衍射等对其进行了结构表征.结果表明,配合物1-4同晶同构,中心原子采取N1O7的配位模式形成扭曲的十二面体几何构型.配合物以菱形四面体Ln8C14O28为基本构筑块,通过O—C—O和氢键形成有序的三维结构.此外,四个配合物均存在镧系收缩效应;配合物1显示出反铁磁性,配合物2对Hg2+有良好的荧光选择性.     

The synthesis,crystal structure and magnetic properties of a one‐dimensional terbium(III)–octacyanidomolybdate(V) assembly

A one‐dimensional cyanide‐bridged coordination polymer, poly[[aquadi‐μ‐cyanido‐κ⁴C:N‐hexacyanido‐κ⁶C‐(dimethylformamide‐κO)bis(3,4,7,8‐tetramethyl‐1,10‐phenanthroline‐κ²N,N′)terbium(III)molybdate(V)] 4.5‐hydrate], [MoTb(CN)₈(C₁₆H₁₆N₂)₂(C₃H₇NO)(H₂O)]·4.5H₂O}_n, has been prepared and characterized through IR spectroscopy, elemental analysis and single‐crystal X‐ray diffraction. The compound consists of one‐dimensional chains in which cationic [Tb(tmphen)₂(DMF)(H₂O)]³⁺ (tmphen is 3,4,7,8‐tetramethyl‐1,10‐phenanthroline) and anionic [Mo^V(CN)₈]³⁻ units are linked in an alternating fashion through bridging cyanide ligands. Neighbouring chains are connected by three types of hydrogen bonds (O—H...O, O—H...N and C—H...O) and by π–π interactions to form a three‐dimensional supramolecular structure. In addition, magnetic investigations show that ferromagnetic interactions exist in the compound.     

Synthesis and structure of the first propeller-shaped helical coordination polymer { [ Ag( S , S) -bis( oxazoline) ] (OTf)}_∞

A mixture of (S,S)-bis(oxazoline) ligand (1) with silver tri-fluoromethane sulfonate afforded a helical coordination polymer (2). Its structure was determined by X-ray single-crystal diffraction.     

掺杂稀土配合物的无机/高分子纳米杂化薄膜的 制备与发光性能

通过在溶胶-凝胶过程中引入高分子组分,并将稀土配合物掺杂其中的方法得到了具有良好发光性能的无机/高分子杂化薄膜,它们有很好的韧性和透明性,测定了薄膜的荧光光谱和荧光寿命,发现它们均发射出稀土离子的特征荧光且寿命比本体配合物增长。透射电镜的观察表明配合物在SiO~2/高分子互穿网络中分布较均匀,分散尺度在20～30nm之间。     

A novel three‐dimensional copper(I) cyanide coordination polymer constructed from various bridging ligands: synthesis,crystal structure and characterization

The cyanide ligand can act as a strong σ‐donor and an effective π‐electron acceptor that exhibits versatile bridging abilities, such as terminal, μ₂‐C:N, μ₃‐C:C:N and μ₄‐C:C:N:N modes. These ligands play a key role in the formation of various copper(I) cyanide systems, including one‐dimensional (1D) chains, two‐dimensional (2D) layers and three‐dimensional (3D) frameworks. According to the literature, numerous coordination polymers based on terminal, μ₂‐C:N and μ₃‐C,C,N bridging modes have been documented so far. However, systems based on the μ₄‐C:C:N:N bridging mode are relatively rare. In this work, a novel cyanide‐bridged 3D Cu^I coordination framework, namely poly[(μ₂‐2,2′‐biimidazole‐κ²N³:N^3′)(μ₄‐cyanido‐κ⁴C:C:N:N)(μ₂‐cyanido‐κ²C:N)dicopper(I)], [Cu₂(CN)₂(C₆H₆N₄)]_n, (I), was synthesized hydrothermally by reaction of environmentally friendly K₃[Fe(CN)₆], CuCl₂·2H₂O and 2,2′‐biimidazole (H₂biim). It should be noted that cyanide ligands may act as reducing agents to reduce Cu^II to Cu^I under hydrothermal conditions. Compound (I) contains diverse types of bridging ligands, such as μ₄‐C:C:N:N‐cyanide, μ₂‐C:N‐cyanide and μ₂‐biimidazole. Interestingly, the [Cu₂] dimers are bridged by rare μ₄‐C:C:N:N‐mode cyanide ligands giving rise to the first example of a 1D dimeric {[Cu₂(μ₄‐C:C:N:N)]ⁿ⁺}_n infinite chain. Furthermore, adjacent dimer‐based chains are linked by μ₂‐C:N bridging cyanide ligands, generating a neutral 2D wave‐like (4,4) layer structure. Finally, the 2D layers are joined together via bidentate bridging H₂biim to create a 3D cuprous cyanide network. This arrangement leads to a systematic variation in dimensionality from 1D chain→2D sheet→3D framework by different types of bridging ligands. Compound (I) was further characterized by thermal analysis, solid‐state UV–Vis diffuse‐reflectance and photoluminescence studies. The solid‐state UV–Vis diffuse‐reflectance spectra show that compound (I) is a wide‐gap semiconductor with band gaps of 3.18 eV. The photoluminescence study shows a strong blue–green photoluminescence at room temperature, which may be associated with metal‐to‐ligand charge transfer.     

Cobalt(II) and silver(I) coordination polymers containing flexible bis (benzimidazol-1-yl)hexane ligands: synthesis,crystal structures,sensing and photocatalytic properties

Two new ternary metal coordination polymers (CPs), namely, {[Co₂(BTC)(L)]·0.25H₂O}_n ( 1 ) and [Ag(HIPA)(L)]_n ( 2 ) (H₄BTC = 1,2,3,4-butanetetracarboxylic acid, H₂IPA = isophthalic acid, L = 1,6-bis(5,6-dimethylbenzimidazol-1-yl)hexane) were hydrothermally synthesized and characterized by elemental analysis, infrared spectroscopy, single-crystal X-ray diffraction, and powder X-ray diffraction (PXRD). 1 exhibits unusual 2D network with point symbol {4³.6³}₂{4⁶.6⁶.7³}. 2 possesses 1D chain structure which is further extended into a 3D supramolecular network via O–H···O hydrogen-bonding and π–π stacking interactions. 1 and 2 can selectively detect benzaldehyde (BZH), Fe³⁺ (just 1 ) and Cr₂O₇²⁻ (just 2 ) ions in water via the luminescence quenching process. Furthermore, the photocatalytic activities of two CPs were evaluated for degradation of methylene blue (MB) and methyl violet (MV) under UV irradiation.     

Two coordination polymers based on semicarbazone Schiff base and azide: synthesis,crystal structure,electrochemistry, magnetic properties and biological activity

[Mn(L)(μ_1,1–N₃)₂]_{2 n} [Mn(H₂O)₂(μ_1,1–N₃)₂] _n (1) and [Cd(HL)(μ_1,1–N₃)₂] _n (2) have been synthesized from HL (HL: pyridine-2-carbaldehyde semicarbazone) and azide ligands, characterized by FT-IR, UV–vis spectroscopy and X-ray crystallography. Single crystal X-ray diffraction revealed that 1 is a coordination polymer consisting of two infinite 1-D chains: chain A with [Mn(L)(μ_1,1–N₃)₂]_{2 n} and chain B with [Mn(H₂O)₂(μ_1,1–N₃)₂] _n . In both chains, Mn centers are connected via two double end-on (EO) azide bridges. 2 is a coordination polymer consisting of a 1-D infinite chain, where Cd centers are connected via two double EO azide bridges. The electrochemistry of HL, 1 and 2 were studied by cyclic voltammetry. Magnetic susceptibility measurements indicate bulk ferromagnetic coupling for 1 below 5?K. Antimicrobial activities of both compounds 1 and 2 were greater than HL, with the strongest effect for 2 consistent with its larger radius and electronegativity of Cd(II) ions.