Two Co(Ⅱ)-based Coordination Polymers Constructed from π-electron-rich Polycarboxylate Aryl Ether Ligand: Structural Insights and Photocatalytic Dye Degradation

In the present study, two new Co(Ⅱ)-based coordination polymers(CPs) with chemical formulas of {[Co_3(μ_3-OH)(L)(H_2O)_3]·2H_2O}_n(1) and {[Co_3(μ_3-OH)(L)(H_2O)]·_2DMF·3H_2O}_n(2) have been successfully prepared by the reaction of Co(NO_3)_2·6H_2O with π-electron-rich polycarboxylate aryl ether ligand 5,5'-((5-carboxy-1,3-phenylene)bis(oxy))diisophthalic acid(H_5L) under different solvothermal reaction conditions. Both CPs have been studied via single-crystal X-day diffraction, powder X-ray diffraction(PXRD) and thermogravimetric analysis(TGA). The photophysical studies indicated that complex 2 with good water stability is a potential semiconductive material, which could be applied for the degradation of methylene blue(MB) under UV light irradiation and exhibit good stability and recyclability.     

Two Zn(Ⅱ)/Cd(Ⅱ) Metal-organic Frameworks Constructed from 1,3,5-Benzenetricarboxylic Acid and1,4-Bis(1-imidazolyl)benzene:Syntheses,Structures and Photoluminescent Properties

Two new d~(10 )metal-based metal-organic frameworks,{[Zn_3(btc)_2(bib)_2(H_2O)_2]·2H_2O}_n(1)and{[Cd_3(btc)_2(bib)_(1.5)(H_2O)_6]·6H_2O}_n(2)(btc=1,3,5-benzenetricarboxylate anion,bib=1,4-bis(1-imidazolyl)benzene)have been prepared under hydrothermal conditions by the reactions of d~(10 )metal oxides of ZnO and CdO with the aromatic polycarboxylic H_3btc and the N-heterocyclic bib.The two products were characterized by single-crystal X-ray diffraction analysis,elemental analysis,thermogravimetric analysis(TGA),and IR spectroscopy.Complexes 1 and 2 crystallize in monoclinic C2/c and triclinic P 1 space groups,respectively.1 shows a 3D framework,and the potential large voids of the 3D network lead to a 3-fold interpenetrating architecture.2 displays a 2D framework,and the adjacent 2D layers expand into a 3D supramulecular network via rich hydrogen bonds.Moreover,the luminescent properties of the two complexes are investigated in solid state.     

SYNTHESIS AND MAGNETIC PROPERTY OF CARBOXYL BRIDGING DICOPPER(Ⅱ) COMPLEXES

Two new dicopper(Ⅱ) complexes with two carboxyl bridgings in one molecule[Cu(dm-phen)(HCOO)]_2(NO_3)_2 3H_2O(1). [Cu(ds-phen)(CH_3COO)]_2 (NO_3)_2 3H_2O(2). one dicopper(Ⅱ) complex with one carboxyl bridging and one hydroxo bridging in one molecule [Cu_2(OH)(C_2H_5COO)(ds-phen)_2]. (NO_3)_2 H_2O(3) and one cononuclear Cu(Ⅱ) complex [Cu(de-phen)(CF_3COO)](NO_3).H_2O(4)(dm-phen= 2,9-dimethyl-1,10-phenanthrolin)were prepared and characterized. The effective magnetic moment, u elf, was measured and their magnetic properties were discussed. The coordination modes of carboxyl moieties in all the title complexes were proposed.     

Two Metal Ion-controlled Zn(Ⅱ)/Cd(Ⅱ) Coordination Polymers Based on 1,3,5-Benzenetricarboxylic Acid

Two new coordination polymers {[Zn(Hbtc)(bpyb)]·H_2O}n(1) and {[Cd(Hbtc)-(bpyb)_(1.5)]·0.5 bpyb}_n(2)(H_3btc = 1,3,5-benzenetricarboxylic acid, bpyb = 1,4-bis(4-pyridyl)benzene) have been synthesized under hydrothermal conditions. The two compounds were characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. Compound 1 displays a 2-fold interpenetrating 3D supramolecular architecture through O–H···N/O hydrogen bonds and π-π stacking interactions. Compound 2 exhibits a 2D→3D polycatenated structure, which is further stabilized by O–H···N hydrogen bonds. The results indicate that the metal ion has significant effects on the formation and structure of the resulted coordination polymers. Furthermore, thermal stability and photoluminescent properties of 1 and 2 are also discussed in detail.     

Structures and Photoluminescent Properties of 3D Ho(Ⅲ) and Y(Ⅲ) Complexes with 2,4,6-Pyridinetricarboxylate

Two 3D rare earth coordination polymers {[Ho(ptc)(H_2O)_(2.5)]·0.5 H_2O}n(1) and {[Y2(ptc)2(H_2O)_5]·H_2O}n(2)(H_3ptc = 2,4,6-pyridinetricarboxylic acid) have been synthesized with Ho(Ⅲ) or Y(Ⅲ) chloride and H_3ptc by hydrothermal method. The X-ray structure analyses display the two complexes are isomorphic and crystallize in monoclinic crystal system with P21/n space group for 1 and P21/c space group for 2. Ho(Ⅲ) and Y(Ⅲ) both show two different coordination modes. One is nine-coordinated and forms a distorted tricapped trigonal prism and the other is eight-coordinated to get a distorted bicapped trigonal prism. The ptc3-also shows two different coordination modes by connecting four or three rare earth ions. The photoluminescent properties of 2 show that it can emit blue fluorescence at 440 nm with excitation at 335 nm. The fluorescence lifetime of 2 is 1.64 μs and the absolute fluorescence quantum yield is 10.2%.     

Syntheses,Structures and Properties of Three Novel La(Ⅲ)/Co(Ⅱ) Coordination Polymers Based on 5-(3-(Tetrazo-5-yl)phenyl)isophthalic Acid

Three novel complexes, namely {[La(tapipa)(4,4′-bibp)·(H_2O)_2]·H_2O}n(1), {[La-(tapipa)(H_2O)_4(OH)]·3 H_2O}n(2), [Co(tapipa)(1,4-bbib)]n(3)(tapipa = 5-(3-(tetrazo-5-yl)phenyl)isophthalic acid, 4,4′-bibp = 4,4′-bis(imidazolyl)biphenyl, and 1,4-bbib = 1,4-bis(benzimidazo-1-ly)benzene) have been synthesized under solvothermal conditions and characterized by PXRD, IR,TGA, and so on. Complex 1 presents a 2 D layer structure, which is finally packed into a 3 D supramolecular structure by means of hydrogen bonds; complexes 2 and 3 exhibit 1 D chains and 2 D wavy-type structures, respectively, which are expanded into 3 D supramolecular structures through hydrogen bonds and π-π interactions. Furthermore, the luminescence properties of complex 1 and the variable-temperature magnetic susceptibilities of 3 were investigated. Complex 1 has highly selective sensing for Fe~(3+) and Cr_2O_7~(2-) ions.     

Crystal Engineering of Co(Ⅱ) Metal-organic Frameworks Based on the Hydrolysis Product of Letrozole and Coligands

The cyanide groups of letrozole(1-[bis(4-cyanophenyl)methyl]-1,2,4-triazole) were hydrolyzed into the carboxylic groups under alkaline conditions. Then the hydrolysis product(1-[bis(4-carboxylphenyl)methyl]-1,2,4-triazole, H_2ltzda) reacted with Co(NO_3)_2·6H_2O in the presence of different bipyridl-typed ligands under hydrothermal conditions. As a result, two new Co(Ⅱ) MOFs were obtained, formulated as [Co_2(ltzda)_2(bpp)_2]_n(1) and {[Co_2(ltzda)_2(bpy)]·4H_2O}_n(2)(bpp = 1,3-di(4-pyridyl)propane, bpy = 4,4'-bipyridine). Two MOFs have been characterized by single-crystal X-ray diffraction, thermogravimetric analysis and magnetic measure. 1 displays a 2D metal-organic framework containing wave layers and 2 shows a pillared-layer structure existing in a 2-fold interpenetrated mode.     

Solvothermal Synthesis,Crystal Structure and Photoluminescence Property of a 3D Lead(Ⅱ) Coordination Polymer Based on Terephthalic Acid

Solvothermal reaction of Pb(NO_3)_2·6H_2O with rigid linear ligand terephthalic acid(H_2pta) in N,N-dimethylformamide(DMF) produced a new three-dimensional(3D) lead(Ⅱ)coordination polymer[Pb_2(pta)_(1.5)(μ4-OH)(DMF)]_n 1,and its structure was characterized by single-crystal X-ray diffraction analyses.In polymer 1,the μ_4-OH bridges the nearby lead(Ⅱ) ions into an infinite one-dimensional(1D) chain,and then the organic ligand pta~(2-) joins the neighbored chains into a 3D structure by two similar connection modes in different configurations.The solid-state photoluminescent studies revealed that 1 exhibits a strong greenish emission mainly originating from ligand-to-metal charge transfer between the delocalized π bonds of the aromatic carboxylate ligand pta~(2-) and the p orbitals of the Pb~(2+) centers.     

Two Coordination Polymers Constructed by Cd(Ⅱ) and Zn(Ⅱ) with in situ Generated 5-(3-Pyridyl)tetrazolate Ligand:Syntheses,Crystal Structures and Luminescence Properties

Hydrothermal reactions of 3-cyanopyridine and Na N3 with Zn Cl_2 or Cd Cl_2·5/2H_2 O in the presence of 1,4-benzenedicarboxylic acid(H2bdc) yielded two new coordination polymers,{[Zn(3-ptz)(bdc)_(0.5)(H_2O)_2]n·2H_2O}_n(1) and [Cd_2(3-ptz)_2Cl_2]_n(2),based on in situ synthesized 5-(3-pyridyl)tetrazolate(3-ptz-) organic ligand.They have been structurally characterized by elemental analysis(EA),infrared spectroscopy(IR) and single-crystal/powder X-ray diffraction(PXRD).In 1,two Zn(Ⅱ) ions are linked together through two μ_2-(3-ptz-) ligands to form a dimeric unit of [Zn(μ_2-3-ptz)(H_2O)_2]_2~(2+),which is further connected with other equivalent units by μ_2-bdc~(2-)spacers,resulting in an infinite 1D polymeric chain of [Zn_2(3-ptz)_2(H_2O)_2(bdc)]_n,and then strong hydrogen bonding interactions extend these 1D chains into a 3D supramolecular structure.In 2,the Cd(Ⅱ) ions are connected through μ_4-(3-ptz-) ligands and Cl-anions,leading to infinite 2D layers of [Cd_2(3-ptz)Cl_2]_n~(n+),which are further linked by another μ_4-(3-ptz-) pillared ligand to form a 3D layered-pillared framework architecture of [Cd)2(3-ptz))2Cl)2])n.Furthermore,thermal stability of these compounds was measured by thermogravimetric analysis(TGA) and their photoluminescent properties were also investigated in the solid state at room temperature.     

Syntheses,Crystal Structures and Properties of Two New Compounds from a Flexible Bipodal Acid with Additional Amide Groups

Two novel compounds {[Cu(IBG)(4,4-bipy)(H_2O)_2]_2·11H_2O}_n(1) and {[Co(IBG)-(μ-H_2O)(H_2O)_2]·2H_2O}n(2) based on isophthaloylbisglycine(H_2IBG) have been synthesized and structurally characterized by thermogravimetric analysis, elemental analysis and single-crystal X-ray diffraction. Compound 1 shows a 1D chain sine/cosine chain structure, and compound 2 can be characterized as a 4-connected sql tetragonal planar network with the point symbol of {44·62}. Compound 2 has been characterized by magnetic measurements. In addition, 1 and 2 display an interesting reversible crystal-to-amorphous transformation.     

Syntheses,Crystal Structures,and Magnetic Properties of Cobalt(Ⅱ) Complexes with 1,1-Cyclohexanediacetic Acid

Two new Co(Ⅱ) coordination polymers,{[Co_3(Hchda)_2(chda)_2(bpp)_2(H_2O)_2]}_n 1 and {[Co(chda)(bpe)(H_2O)]·3H_2O}_n 2(H_2chda = 1,1-cyclohexanediacetic acid,bpp = 1,3-bis(4-pyridinyl)propane and bpe = 1,2-bis(4-pyridinyl)ethylene),were hydrothermally synthesized and then characterized by elemental analysis,IR spectroscopy,thermogravimetric analysis(TGA),and single-crystal X-ray diffraction.Complex 1 possesses an infinite metal-organic layer based on triply bridged linear trinuclear subunits and complex 2 exhibits a square(4,4) grid layer with dangling lateral arms resulting from eight-membered rings above and below the layer.In addition,magnetic properties of complexes 1 and 2 are also given.     

Two Tetranuclear Zinc(Ⅱ) Coordination Polymers Based on 3,5-Bis(2-carboxylphenoxy)benzoic Acid with Highly Selective Sensing of Nitrobenzene

Two novel zinc(Ⅱ) coordination polymers, [Zn_2(BCB)(CH_3OH)(μ_3-OH)]n(1) and {[Zn_2(BCB)(μ_3-OH)(H_2O)_2]·CH_3OH}n (2), have been constructed from 3,5-bis(2-carboxylphenoxy)benzoic acid(H_3BCB) and characterized by elemental analysis(EA), IR, powder X-ray diffraction(PXRD), and thermogravimetric(TG) analyses. Structural analysis reveals that complexes 1 and 2 are both 1D polymeric chains with unprecedented tetranuclear {Zn_4(COO)_4(μ_3-OH)_2} clusters, which were further expanded into a 2D structure. Fluorescence measurements show that 1 and 2 have highly selective and sensitive detection of nitrobenzene.     

Three Co(Ⅱ) Coordination Polymers Incorporated with a Bent Connector: Crystal Structures and Magnetic Properties

Based on the bent ligand 1 H-3-(3-pyridyl)-5-(4-pyridyl)-1,2,4-triazole(3,4?-Hbpt) with Co(Ⅱ) ions as well as a series of polycarboxylate co-ligands, three new coordination polymers were yielded, namely, {[Co(op)(3,4?-Hbpt)(H_2O)_3]?2 H_2O}n(1), [Co(cyc)(3,4′-Hbpt)(H_2O)]n(2) and [Co(pro)(3,4′-Hbpt)(H_2O)]n(3)(here, op = o-phthalic anion, cyc = 1,1-cyclobutanedicarboxylic anion, pro = propanedioic anion). In cooperation with the auxiliary polycarboxylate co-ligands, a variety of Co(Ⅱ) coordination networks, such as 1-D chain 1 and 2-D layer 2 and 3 have been assembled. The magnetic behaviors of compounds 1～3 were studied. All of them indicated the existence of interesting spin-canting behavior.     

Syntheses,Structures,and Photoluminescent Properties of Two Zn(Ⅱ) Coordination Polymers with Helical Chains Structures

Two novel coordination polymers with helical chains, {[Zn(L)(H2O)]?H2O}n(1) and {[Zn(L)(p-bix)]?3.5H2O}n(2), where H2 L = 5-(4-hydroxypyridinium-1-ylmethyl) isophthalic acid and p-bix = 1,4-bis(imidazol-1-ylmethyl)benzene, have been hydrothermally synthesized, and charac-terized by elemental analysis, powder X-ray diffraction(PXRD), IR, thermal gravimetric analyses(TGA) and also by single-crystal X-ray diffraction. Both complexes 1 and 2 crystallize inmonoclinic, space group P21/c. Compound 1 displays a two-dimensional(2D) structure with two distinct types of helical chains; 2 shows a layered coordination polymer with two types of helical chains and features an interesting 2D→3D interdigitated architecture. Meanwhile, the luminescent properties of 1 and 2 have also been investigated in detail.     

Synthesis and Characterization of Heterobimetallic Zigzag Chains with a Close-packed Structure Based on Macrocyclic Metalloligands

Two new heterobimetallic coordination polymers {[Co(NiL)(H_2O)_3]·4H_2O}_n(1) and {[Cu(NiL)(H_2O)_3]·4H_2O}_n(2) were synthesized based on metalloligand under the same self-assembly conditions. X-ray diffraction analyses reveal that the two compounds involve close-packed zigzag chains, which expand into various three-dimensional supramolecular frameworks through the second interactions such as hydrogen bonds and π···π stacking interactions. In these two compounds, NiL as a bridging ligand chelates the metal ion nodes via two oxamido carbonyls and carboxylate oxygen atom. The central Co(Ⅱ) and Cu(Ⅱ) ions in 1 and 2 both exhibit distorted octahedral coordination geometry. They are bridged by macrocyclic oxamido metalloligands fusing the zigzag chains with a ‘‘head-to-tail' arrangement. The Ni(Ⅱ) ion in metalloligand is coordinated by four nitrogen atoms with the [NiN4] chromophore exhibiting distorted planarity. The two investigated compounds were further characterized by thermogravimetric analysis and FT-IR spectroscopy. The fluorescent properties of 1 and 2 in the solid state were also investigated.     

Syntheses and Crystal Structures of Two Copper(Ⅱ) Coordination Polymers Derived from Aromatic Carboxylic Acids and Bis(imidazoles) Ligands

Two compounds have been obtained by the reaction of metal(Cu(II)), 4,4?-bis(imidazol-l-yl)diphenyl thioether(BIDPT) with two carboxylic acids, 4,4?-oxydibenzoic acid(H_2oba) and phthalic acid(H_2pht). The crystal structures of the resulting compounds, namely {[Cu(BIDPT)(oba)]·H2O}n(1) and {Cu(BIDPT)(pht)}n(2), have been determined by single-crystal X-ray diffraction analysis. Compound 1 is of orthorhombic system, space group Pbcn with a = 27.8310(3), b = 10.7791(1), c = 19.3913(2) ?, V = 5817.0(3) ?3 and Mr = 656.15. Compound 2 belongs to the monoclinic system, space group C2/c with a = 18.2678(2), b = 11.0259(1), c = 22.906(2) ?, β = 97.727(2)o, V = 4571.8(8) ?3 and Mr = 545.04. Structural analyses reveal that compounds 1 and 2 respectively exhibit two-dimensional(2D) wavy and corrugated layer structures. Through intermolecular hydrogen bonding, compound 1 is assembled into a 3D supramolecular structure. The thermal stability and ultraviolet spectroscopy properties of the two compounds are also investigated.     

Syntheses,Crystal Structures,and Magnetic Properties of Mn(Ⅱ) and Co(Ⅱ) Coordination Polymers Constructed from Pyridine-tricarboxylate Ligand

Two coordination polymers, namely {[Mn(HL_1)(phen)]·4H_2O}_n(1) and [Co_2(HL_2)_2(H_2O)_2]_n(2) have been constructed hydrothermally using H_3L_1 and H_3L_2(H_3L_1 = 2-(5-carboxypyridin-2-yl)terephthalic acid, H_3L_2 = 2-(4-carboxypyridin-3-yl)terephthalic acid), phen, MnCl_2×4H_2O and CoCl_2×6H_2O. The products were isolated as stable crystalline solids and were characterized by IR spectroscopy, elemental, thermogravimetric(TGA), powder(PXRD) and single-crystal X-ray diffraction analyses. Compound 1 features a 3D framework structure, which was topologically classified as a trinodal 4,6,6-connected net with the unique topology defined by the point symbol of(3~(10).5.6~4)4(3~(10).6.7~4)2(5.6~2.8~2.9). Compound 2 possesses a 2D metal-organic layer, which was topologically classified as a binodal 4,4-connected layer defined by the point symbol of(4~3.6~2.8). The layers are further extended into a 3D supramolecular framework via hydrogen bonds. The magnetic properties for both compounds were also investigated, indicating antiferromagnetic interactions between the adjacent metal ions.     

Syntheses and Anti-lung Cancer Effects of Two Novel Dy(Ⅲ) Complexes Based on 1,3,5-Benzenetricarbocylic Acid and 1,3,5-Benzenetrisbenzoic Acid,respectively

The reactions of 1,3,5-benzenetricarbocylic acid(H3BTC) and 1,3,5-benzenetrisbenzoic acid(H3BTB) with Dy(NO3)3·6H2O afford two novel Dy(III) coordination polymers respectively, Dy(BTC)(H_2O)DMF(1) and [Dy(BTB)(Et OH)](DMF)(2)(DMF = N,N-dimethylformamide). 1 shows a 3D framework composed of available Lewis-acid metal sites which are occupied by the coordinated water molecules, and 2 features a noninterpenetrated open 3D framework with a 5-connected bnn hexagonal topology possessing the point symbol(46.64). In addition, in vitro antitumor activities of compounds 1 and 2 on three human lung cancer cells(H1975, HCC827 and A549) were further determined.     

Hydrothermal Syntheses,Crystal Structures and Luminescence Properties of Cu(Ⅱ) and Cd(Ⅱ) Complexes Assembled by 6-Hydroxypicolinic Acid and 1,10-Phenanthroline

Two new complexes based on 6-hydroxypicolinic acid(H_2picO) and 1,10-phenanthroline(phen), such as [Cu_4(picO)_4(phen)_4]·12 H_2O(1) and {[Cd_4(picO)_4(phen)_4(H_2O)_2]·5H_2O}_n(2), have been synthesized and characterized by IR, elemental analyses, thermogravimetric analyses and X-ray diffraction technique. Single-crystal X-ray diffraction analyses revealed that the two complexes both crystallize in the triclinic system, space group P(16)-. For complex 1, the picO ligands adopt a tridentate coordination mode to link copper(Ⅱ) ions into dimmers. PicO ligands also adopt a tridentate mode in complex 2, which connects the cadmium(Ⅱ) to form a one-dimensional chain. Moreover, luminescent properties of 1 and 2 were also investigated.     

Structural Diversity and Photoluminescent Properties of Two Mn(Ⅱ) Sulfoterephthalate Complexes from Multi-pyridine N-containing Ligands

Solvothermal reaction of manganese(II) salt with monosodium 2-sulfoterephthalate(2-NaH_2stp) and two multi-pyridine N-containing auxiliary ligands results in the formation of two new complexes formulated with [Mn_2(Hstp)_2(bpp)_2(H_2O)_4](1) and [Mn_3(stp)_2(tpy)_3(H_2O)](H_2O)_5(2)(bpp = benz-2,3-pyrimidine-[2,3-f]-1,10-phenanthroline, tpy = 2,2?:6?,2??-terpyridine). X-ray diffraction structural analyses of two complexes reveal their structural diversity(0D and 1D) due to the difference of auxiliary ligands. 1 is a discrete structure, in which the Mn(Ⅱ) ion is hexa-coordinated with one stp, one bpp ligand and two water molecules. Complex 2 is a one-dimensional(1D) chain-like structure with three crystallographically independent Mn(Ⅱ) ions. The photoluminescent properties could be assigned to the π-π* transition of 2-sulfoterephthalate ligands.