Three double- or triple-stranded chains constructed from different cobalt(II) salts and a flexible bis-triazole ligand

Three coordination compounds, {[Co(btrp)₂(H₂O)₂]?·?NO₃?·?H₂O} _n (1), {[Co(btrp)₂(H₂O)₂]?·?H₂O?·?2H₂btc} _n (2), and {[Co(btrp)₃]?·?2ClO₄} _n (3) (btrp?=?1,3-bis(1,2,4-triazol-1-yl)propane; H₃btc?=?benzene-1,3,5-tricarboxylic acid), have been prepared via solvothermal method and characterized by single-crystal X-ray diffraction and elemental analyses. Compound 1 possesses a 1-D double-stranded chain composed of ribbons of 20-membered cycles. Binuclear water clusters link adjacent nitrate anions to form a 1-D supramolecular helix in the structure. Compound 2 has a 1-D double-stranded chain wherein free H₂btc ligands constitute 1-D negative chains through classical hydrogen-bonding interactions (O–H?···?O). Compound 3 exhibits a triple-stranded 1-D chain. For 1–3, 3-D supramolecular structures are consolidated by interchain weak hydrogen-bonding interactions as well as electrostatic interactions.     

Crystal engineering of Cd(II) metal–organic frameworks bridged by dicarboxylates and N-donor coligands

Two new metal–organic coordination polymers, {[Cd₄(bpea)₄(IP)₈]?·?6H₂O} _n (1) and {[Cd_1.5(suc)_1.5(IP)_1.5]?·?4H₂O} _n (2) (bpea?=?biphenylethene-4,4′-dicarboxylate, H₂suc?=?succinic acid and IP?=?1H-imidazo[4,5-f][1,10]-phenanthroline), have been obtained through two types of dicarboxylate linkers. Complex 1 contains a neutral 2-D puckered sheet that is interdigitated by neutral 1-D zigzag chains. Compound 2 shows a 2-D (4,4) net, which is extended into a 3-D supramolecular framework by weak aromatic interactions. The different structures demonstrate the effect of the dicarboxylate ligands on the formation of such coordination architectures. The fluorescence property of the two complexes was also investigated.     

Copper(II) coordination polymers constructed from aromatic polycarboxylate and flexible triazole ligands with different spacer lengths: syntheses,structures, and properties

{[Cu₂(btm)₂(Hbtc)(H₂btc)₂(H₂O)]·9.5H₂O}_n (1), [Cu(bte)(H₂btc)₂]_n (2) {[Cu(btp)(H₂btc)₂]·0.25H₂O}_n (3) (btm?=?bis(1,2,4-triazol-1-yl)methane, bte?=?bis(1,2,4-triazol-1-yl)ethane, btp?=?bis(1,2,4-triazol-1-yl)propane, H₃btc?=?benzene-1, 3, 5-tricarboxylic acid) have been synthesized and structurally characterized. 1 features a 1-D double chain, which is interconnected by classical hydrogen-bonding (O–H?O) and π–π interactions to lead to a 3-D supramolecular architecture. 2 and 3 are both 1-D single chains, which are interconnected by π–π interactions to 2-D layer architectures. Elemental analysis, XRD, IR, TG and EPR spectra have been carried out and discussed.     

Syntheses,crystal structures,and photoluminescence of two Cd(II) complexes with simple ligands

Two cadmium complexes, {[Cd₂(2,5-tda)₂(ip)₄]·4H₂O}_n (1) and {[Cd₂(4,4′-obb)₂(ip)₂·H₂O]·H₂O}_n (2) (2,5-tda?=?thiophene-2,5-dicarboxylic acid, 4,4′-obb?=?4,4′-oxybisbenzoic acid, ip?=?1H-imidazo[4,5-f][1, 10]-phenanthroline), were synthesized and characterized by IR, elemental analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. X-ray analysis revealed that 1 is a dinuclear complex with the 2,5-tda anion connecting two Cd ions in a μ₁-η¹:η⁰/μ₁-η¹:η⁰ coordination mode. Each dinuclear complex is further connected with neighboring complexes via hydrogen-bonding interactions. Compound 2 displays a 2-D layer structure with opened windows occupied by crystallographic water molecules. The layers are further packed via hydrogen-bonding interactions. Luminescent properties for 1 and 2 are also investigated in the solid state at room temperature.     

Syntheses,structures, and properties of CdII and CoII complexes with 5-(pyridin-4-yl)isophthalate

A N-donor containing carboxylic ligand, 5-(pyridin-4-yl)isophthalic acid (H₂L), was applied to construct two new coordination polymers [Cd(L)(DMF)] _n (1, DMF?=?N,N-dimethylformamide) and {[Co(L)(H₂O)₂]?·?0.5CH₃OH?·?1.5H₂O} _n (2) under different conditions. The complexes were characterized by IR, elemental, and thermogravimetric analyses, powder and single crystal X-ray diffraction. In 1 each L^2? links four Cd^II to form a 3-D framework, while in 2 each L^2? connects three metals to form a 2-D layer structure, which is further connected together by hydrogen bonds to form a 3-D architecture. The thermal stability of the complexes and the photoluminescence of 1 were investigated.     

Syntheses,crystal structures,and fluorescent properties of two Cd(II) complexes based on 2,2′-(ethane-1,2-diyl)bis(1H-imidazole-4,5-dicarboxylic acid)

Two new complexes, [Cd₂(H₄ebidc)₂(CH₃OH)₄]?·?2CH₃OH (1) and {[Cd(Cl)(I)(H₆ebidc)_1/2]?·?1/2bbe?·?H₂O} _n (2) (H₆ebidc?=?2,2′-(ethane-1,2-diyl)bis(1H-imidazole-4,5-dicarboxylic acid), bbe?=?1,2-bis(2-benzimidazolyl)ethane), are obtained through self-assembly of H₆ebidc with Cd(II). Single-crystal X-ray diffraction shows that 1 has a binuclear structure and each tridentate chelating ligand coordinates to two Cd(II) ions with µ₂-O. Complex 2 displays a 1-D chain structure and each tetradentate ligand bridges two Cd(II) ions in chelating fashion. Fluorescent properties have also been determined.     

Syntheses,structures, and magnetism of two coordination compounds with 3,3′,4,4′-biphenyltetracarboxylic acid and 1,10-phenanthroline

Two coordination polymers, {[Mn(1,10-phen)₂(3,4-H₂bptc)]?·?(H₂O)}_{2 n} (1) and {[Co₂(1,10-phen)(3,4-bptc)(H₂O)₂]?·?H₂O} _n (2) (3,4-H₄bptc = 3,3′,4,4′-biphenyltetracarboxylic acid, 1,10-phen?=?1,10-phenanthroline), have been prepared and structurally characterized. In both compounds, 3,4-H₂bptc^2– and 3,4-bptc^4? exhibit different coordination modes and lead to various architectures. Compound 1 displays 1-D zigzag chains constructed with hydrogen bonds. Compound 2 exhibits a 2-D layer constructed from bpta^4? between the dinuclear Co(II) units. The thermal stabilities and magnetic properties are also reported. In addition, 1 was explored as a luminescent material. The carboxylic oxygen atoms act as H-bond acceptors and donors forming a 1-D ladder-like arrangement.     

Two solvent directed zinc(II) coordination polymers with 1-D single-zigzag chain and 1-D double-zigzag chains

Two coordination polymers, {[Zn(NiL)(DMA)(H₂O)₂] (DMA)(H₂O)} _n (1) (DMA?=?N,N-dimethylacetamide) and {[Zn₂(NiL)₂(DMF)(H₂O)₄]?·?3DMF} _n (2) (DMF?=?N,N-dimethylformamide), have been prepared by reactions of Zn(NO₃)₂?·?6H₂O and NiL in CH₂Cl₂-DMA–H₂O and CH₂Cl₂-DMF–H₂O, respectively. H₂L denotes dimethyl 5,6,7,8,15,16-hexahydro-6,7-dioxodibenzo-9,10-benzo-[1,4,8,11]tetraazacyclotetradecine-13,18-dicarboxylate. Single-crystal X-ray diffraction analyses reveal that coordination geometries around Ni(II) are identical with slightly distorted square planar and all Ni–N bonds are very short. Complex 1 shows 1-D zigzag chain structure, while 2 has 1-D double-zigzag chains. The chains, which are packed parallel in 1 and 2, are interconnected by lattice solvent through O–H···O and C–H···O hydrogen bonds to form 3-D supramolecular networks. We discuss solvent effects on assembly of the two coordination polymers. The results reveal that coordinated solvent has influence on the assembly procedure.     

Syntheses,structures, and fluorescent properties of two new d10-metal coordination polymers containing 1-((benzotriazol-1-yl)methyl)-1-H-1,2,4-triazole ligand

Two new coordination polymers formulated as {[Zn(bdic)(bmt)H₂O]?·?0.5H₂O} _n (1) and {[Cd(bdic)(bmt)(H₂O)₂]?·?2H₂O} _n (2) (H₂bdic?=?1,3-benzenedicarboxylic acid, bmt?=?1-((benzotriazol-1-yl)methyl)-1-H-1,2,4-triazole) have been synthesized and characterized by elemental analysis, IR, and single-crystal X-ray diffraction. Both coordination polymers exhibit 1-D chain structure where bmt is unidentate and bdic^2? bridging. In 1, bmt hangs at two sides of the main chain, whereas bmt hangs at one side of the main chain in 2. Fluorescent properties have also been determined.     

Syntheses,structures, and luminescence of three 4-connected zinc coordination polymers with bis(1,2,4-triazol-1-yl)propane and benzenebiscarboxylate

Three zinc(II) coordination polymers {[Zn(btp)(1,2-bdc)(H₂O)]?·?H₂O} _n (1), {[Zn(btp)(1,3-bdc)(H₂O)]?·?1.5H₂O} _n (2), and {[Zn(btp)(NO₂-1,3-bdc)(H₂O)]?·?2H₂O} _n (3) were synthesized by 1,3-bis(1,2,4-triazol-1-yl)propane (btp) and bis-carboxylate. Compound 1 is a thick 2-D network; 2 and 3 are undulated 2-D (4,4) networks. In 2 and 3, two adjacent networks interpenetrate to form a new 2-D double-layer network, which is sustained by hydrogen-bonding interactions. Compounds 1 and 2 reveal blue emission maximum at 351 and 403, respectively, in the solid state at room temperature.     

A series of lanthanide-organic frameworks constructed by 2-methyl imidazole dicarboxylate and oxalate: synthesis,structures, and properties

Five lanthanide(III) coordination polymers with 2-methyl-1H-imidazole-4,5-dicarboxylic acid (H₃MIDC) and ammonium oxalate, {[(Ln1)₂(HMIDC)₂(C₂O₄)(H₂O)₃]?·?3H₂O} _n (Ln1?=?Nd (1), Sm (2)), {[Eu₂(HMIDC)₂(C₂O₄)(H₂O)₃]?·?0.5EtOH?·?3H₂O} _n (3), {[Ce₂(HMIDC)₂(C₂O₄)(H₂O)₃]?·?EtOH?·?3H₂O} _n (4), and {[Gd₂(HMIDC)₂(C₂O₄)(H₂O)₃]?·?MeOH?·?3H₂O} _n (5), have been prepared and structurally characterized. Single-crystal X-ray diffraction analyses reveal that 1 and 2 are isostructural, as are 3, 4, and 5. Each exhibits a 3-D open framework, which is built by a regular 2-D grid connected by HMIDC^2? and Ln(III). The luminescence and thermal properties of these complexes have been investigated as well.     

Supramolecular architecture built of Co(II) and a tripodal ligand containing 1-D water tapes with (H2O)16 cluster units

The reaction of Co(NO₃)₂?·?6H₂O with a tripodal ligand leads to a new complex {[Co(L)]?·?2NO₃?·?8H₂O} (1) confirmed by single-crystal X-ray diffraction, infrared spectroscopy, and elemental analysis. The particular interest of 1 is in the formation of a 1-D water tape consisting of (H₂O)₁₆ cluster units, the neighboring water tapes are connected by free nitrate anions via hydrogen bonds into a 2-D guest layer. These guest layers are alternately packed face-to-face with the 2-D host layers along the a-axis to form a 3-D supramolecular architecture. There exist C–H?···?N and C–H?···?O weak hydrogen bonds between the guest layer and host layer. These weak hydrogen bonds and water–nitrate, water–water hydrogen bonds are important for the stability of the overall structure.     

Three 4-connected nickel coordination polymers affording a 3-D CdSO4 network and two 2-D (4,4) networks

The self-assembly reaction of 1,4-bis(1,2,4-triazol-1-yl)butane (btb) and Ni(II) salts gives three coordination polymers {[Ni(btb)₂(NCS)₂]?·?H₂O} _n (1), [Ni(btb)₂(NCO)₂] _n (2), and [Ni(btb)₂Cl₂] _n (3). Compound 1 is comprised of a twofold interpenetrating 4-connected 6⁵?·?8-CdSO₄ 3-D coordination network. Compounds 2 and 3 are neutral 2-D (4,4) networks with the ABAB?···?and ABCABC?···?stacking modes, respectively. The thermal stabilities of 1–3 were investigated.     

Syntheses,crystal structures,and fluorescent properties of two 2-D Cd(II) complexes based on 2-((1H-1,2,4-triazol-1-yl)methyl)-1H-benzimidazole and 1,2,4,5-benzenetetracarboxylate

Two complexes formulated as {[Cd(btec)_0.5(tmb)H₂O]·4H₂O}_n (1) and {[Cd(H₂btec)(tmb)(H₂O)]·2H₂O}_n (2) (H₄btec?=?1,2,4,5-benzenetetracarboxylic acid, tmb?=?2-((1H-1,2,4-triazol-1-yl)methyl)-1H-benzimidazole) have been synthesized and characterized by elemental analysis, IR, and single crystal X-ray diffraction. Single crystal X-ray diffraction shows that 1 has a 2-D layer structure in which tmb bridges and all of the carboxylates from 1,2,4,5-benzenetetracarboxylate chelate. In 2 Cd(II) ions are bridged by monodentate carboxylates leading to a 2-D layer structure with all tmb ligands coordinated monodentate to Cd(II), hanging at two sides of the layers. Complexes 1 and 2 are further extended to 3-D supramolecular structures by hydrogen bonding interactions. Luminescent properties have been investigated in the solid state at room temperature.     

Two- and three-dimensional coordination complexes constructed by 2-(1H-imidazol-1-methyl)-1H-benzimidazole: syntheses,structures, and fluorescent properties

Two new complexes, {[Zn(imb)(SO₄)]·H₂O}_n (1) and {[Cd₂(imb)₂(SO₄)₂(H₂O)]·CH₃OH}_n (2) (imb?=?2-(1H-imidazol-1-methyl)-1H-benzimidazole), have been solvothermally synthesized. Single-crystal X-ray diffraction shows that 1 displays a 2-D (4,4) network, which is further extended to a 3-D supramolecular structure by hydrogen bonding interactions. Complex 2 exhibits a 3-D framework with (3,5)-connected (4²·6)₂(4²·6⁵·8³)₂ topology. The results indicate that changing metal ions can influence the coordination modes of sulfate, and then affect the structures of the complexes. In addition, IR and UV–vis spectra, powder X-ray diffraction patterns, thermogravimetric analyses, and fluorescent properties of both complexes have been investigated.     

Syntheses,structural determination,and binding studies of binuclear eight-coordinate (enH2)[GdIII 2(pdta)2(H2O)2] · 8H2O and mononuclear nine-coordinate (enH2)[GdIII(egta)(H2O)]2 · 6H2O

The (enH₂)[Gd^III ₂(pdta)₂(H₂O)₂]?·?8H₂O (1) (en?=?ethylenediamine and H₄pdta?=?propylenediamine-N,?N,?N′,?N′-tetraacetic acid) and (enH₂)[Gd^III(egta)(H₂O)]₂?·?6H₂O (2) (H₄egta?=?ethyleneglycol-bis-(2-aminoethylether)-N,?N,?N′,?N′-tetraacetic acid) complexes were synthesized and characterized by infrared spectrum, thermal analysis, and single-crystal X-ray diffraction. The complex (enH₂)[Gd^III ₂(pdta)₂(H₂O)₂]?·?8H₂O has a binuclear eight-coordinate structure with pseudo square antiprism and crystallizes in the monoclinic crystal system with C2/c space group. Through a carboxylate bridge, an infinite 1-D zigzag polymeric binuclear [Gd^III ₂(pdta)₂(H₂O)₂]^2? complex anion is formed. All infinite zigzag polymeric complex anions link through hydrogen bonds, yielding a layer structure. (enH₂)[Gd^III(egta)(H₂O)]₂?·?6H₂O has a mononuclear nine-coordinate structure with pseudo monocapped square antiprism and crystallizes in the monoclinic crystal system with P2₁/n space group. Each enH₂ ²⁺ cation, through hydrogen bonds, connects two adjacent [Gd^III(egta)(H₂O)]^? complex anions.     

From discrete dinuclear to 1-D and 2-D structures: nickel dipicolinate complexes with flexible bis(imidazole) ligands

Three new complexes, [Ni₂(dpc)₂(L₁)₂(H₂O)₂]?·?4H₂O (1), [Ni(dpc)(L₂)_1.5] _n (2), and {[Ni(dpc)(L₃)_1.5]?·?2H₂O} _n (3), where H₂dpc?=?dipicolinic acid, L₁?=?1,4-bis(2-methylimidazol-1-yl)butane, L₂?=?4,4′-bis(2-methylimidazol-1-ylmethyl)biphenyl, and L₃?=?1,4-bis(benzimidazol-1-yl)-2-butylene, have been synthesized by hydrothermal methods and characterized by elemental analyses, infrared spectra, thermogravimetric analysis, and X-ray crystallography. The common structural characteristic of the three complexes is that the Ni²⁺ is coordinated by tridentate dipicolinate through nitrogen of pyridine and oxygen of carboxylate, serving as a terminal ligand. In 1, two L₁ link two [Ni(dpc)(H₂O)] units to a discrete binuclear metallomacrocycle with a 22-membered ring, which is assembled through multiple O–H?···?O hydrogen bonds to form a 3-D supramolecular framework. Complex 2 exhibits a 1-D ladder-like chain structure constructed by cis/trans-conformation L₂ linking metal centers; 3 displays a 2-D (6,3) topology, being constructed from the linking of [Ni(pdc)] by L₃. These results indicate the merits of flexible bis(imidazole) ligands as building blocks with dipicolinate for the construction of complexes with diverse structural motifs.     

Supramolecular networks constructed by cationic copper(II) complexes incorporating hybrid water–anionic polymeric assemblies

Two complexes, [Cu₂(TFSA)(2,2′-bpy)₄]?·?TFSA?·?8H₂O (1) and {[Cu(4,4′-bpy)(H₂O)₂]?·?TFSA?·?6H₂O} _n (2) (H₂TFSA?=?tetrafluorosuccinic acid, 2,2′-bpy?=?2,2′-bipyridine, and 4,4′-bpy?=?4,4′-bipyridine), have been synthesized and structurally characterized by X-ray structural analyses. Complex 1 is a binuclear molecule bridged by TFSA ligands; 2 is a 1-D chain bridged by 4,4′-bpy ligands. The asymmetric units of the two complexes are composed of cationic complexes [Cu₂(TFSA)(2,2′-bpy)₄]²⁺ (1) and [Cu(4,4′-bpy)(H₂O)₂]²⁺ (2), free TFSA anion, and independent crystallization water molecules. A unique 2-D hybrid water–TFSA anionic layer by linkage of {[(H₂O)₈(TFSA)]^2?} _n fragments consisting of 1-D T6(0)A2 water tape and TFSA anionic units by hydrogen bonds in 1 was observed. Unique 2-D hybrid water–TFSA anionic layer generated by the linkage of {[(H₂O)₆(TFSA)]^2?} _n fragments consisting of cyclic water tetramers with appended water molecules and TFSA anionic units, and 1-D metal–water tape [Cu–H₂O?···?(H₂O)₆?···?H₂O^?] _n in 2 were found. 3-D supramolecular networks of the two complexes consist of cationic complexes and water–TFSA anionic assemblies connected by hydrogen bonds.     

Syntheses and structural characterizations of three transition metal coordination complexes based on flexible 2,4-dichlorophenoxyacetate (2,4-DCP)

Three transition metal coordination complexes, {[Co(2,4-DCP)₂(μ ₂-H₂O)(H₂O)₂]?·?(H₂O)₂} _n (1), [Zn(2,4-DCP)(IN)] _n (2), and [Mn₂(2,4-DCP)₃(DMPY)₂(μ ₂-H₂O)(H₂O)]?·?(2,4-DCP)?·?0.2(H₂O) (3) (2,4-DCP?=?2,4-dichlorophenoxyacetate, IN?=?isonicotinate, DMPY?=?5,5′-dimethyl-2,2′-bipyridine), have been prepared under hydrothermal conditions and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. Complex 1 displays a 1-D chain through cobalt and bridging water molecules with Co?···?Co distance of 4.028(2)?Å. Complex 2 shows a 2-D (4,4) net, which is extended into a 3-D supramolecular framework by weak hydrogen-bonding interactions. Complex 3 consists of discrete dinuclear cations, 2,4-DCP counter ions and free water molecules, which are assembled into a packing structure through π?···?π stacking of inversion-related DMPY ligands and hydrogen bonds. Magnetic susceptibility measurements show weak antiferromagnetic interactions in 1. The photoluminescence and lifetime of 2 in the solid state have also been studied.     

Syntheses,crystal structures and antibacterial activities of M(II) benzene-1,2,3-triyltris(oxy)triacetic acid complexes

Four metal(II) complexes with benzene-1,2,3-triyltris(oxy)triacetic acid (H₃L), {[Co_1.5(L)(H₂O)₆]·6H₂O}_n (1), {[Co_1.5(L)(4,4′-bipy)_1.5(H₂O)₄]·4H₂O}_n (2), {[Co(HL)(2,2′-bipy)(H₂O)₂]·1.5H₂O}_n (3), and {[Cu(HL)(phen)(H₂O)₂]·H₂O}_n (4) (4,4′-bipy = 4,4′-bipyridine; 2,2′-bipy = 2,2′-bipyridine; phen = phenanthroline), were prepared and structurally characterized. Complex 2 displays a 1-D structure, while 1, 3, and 4 reveal 0-D structures, which further extend to 3-D supramolecular networks by hydrogen bonding interactions, of which 1 and 4 contain double-helical chains, 2 includes meso-helices, and 3 comprises single-helices. Furthermore, the thermal stabilities and antibacterial activities of the complexes were studied.