Coordination assemblies of rigid–flexible 1,3-bis(5-(pyridine-2-yl)-1,2,4-triazole-3-yl)propane ligands with MCl<Subscript>2</Subscript> (M = Fe,Co, Cu or Zn): structural diversity and mass spectra

Reactions of the rigid–flexible N-heterocycle 1,3-bis(5-(pyridine-2-yl)-1,2,4-triazole-3-yl) propane (H₂L) with MCl₂ (M = Fe, Co, Cu or Zn) gave coordination complexes, {[Fe ₂ ^III Cl₄(H₂L)₂]·2Cl}·EtOH·H₂O (1), {[Co₃Cl₅(HL)]·H₂O} _n (2), {[Co₄Cl₄(H₂L)₂(H₂O)₄]·[CoCl₄]₂}·H₂O (3), [Cu₂Cl₃(HL)(H₂O)]₆·5H₂O (4), [Cu ₂ ^II Cu^ICl₄(HL)] _n (5), {[Zn₂Cl₂(L)H₂O]·H₂O} _n (6) and [Zn₄Cl₆(HL)₂] (7), which have been characterized by single-crystal X-ray diffraction. Structural analysis reveals that the pyridine triazole ligand attains versatile coordination modes in these complexes. Complexes 1, 3, 4 and 7 consist of 0D clusters with binuclear or tetranuclear units; complex 2 presents a 2D network accompanied by HL^? and chloride bridges; complexes 5 and 6 show 1D chains with [Cu₃] and [Zn₂] subunits. In addition, the electrospray ionization mass spectrometry properties of selected complexes were investigated, revealing the stabilities and structural states of these complexes in solution. These results indicate that H₂L is an excellent multiconnection linker for the construction of diverse coordination complexes.     

Three new manganese(II) coordination complexes based on tetrazole carboxylate ligands

Reactions of three tetrazole carboxylate ligands, namely 5-(4-pyridyl)tetrazole-2-acetic acid (Hpytza), 1,3,5-tris(tetrazol-5-yl)benzene-N2,N2′,N2″-triacetic acid (H₃tzpha) and 5-aminotetrazole-1-propanoic acid (Hatzpa) with Mn(NO₃)₂·6H₂O in the presence of KOH afforded three new complexes, [Mn(pytza)₂] (1), [Mn₃(tzpha)₂(H₂O)₁₂]·2CH₃OH·10H₂O (2) and [Mn(atzpa)₂(H₂O)₂] (3), respectively. These complexes were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Complex 1 displays a three-dimensional network while 2 and 3 show one-dimensional chains. Furthermore, the luminescence properties of these complexes were investigated at room temperature in the solid state.     

Synthesis,crystal structures,and properties of copper(II) dicarboxylate complexes with [bis(2-pyridylcarbonyl)amido]

Four new complexes, [Cu₂(Bpca)₂(L¹)(H₂O)₂] · 3H₂O (I), [Cu₂(Bpca)₂(L²)(H₂O)₂] (II), [Cu₂(Bpca)₂(L³)] · 2H₂O (III), [Cu₂(Bpca)₂(L¹)(H₂O)] · 2H₂O (IV) (Bpca = bis(2-pyridylcarbonyl)amido, H₂L¹ = glutaric acid, H₂L² = adipic acid, H₂L³ = suberic acid, H₂L⁴ = azelaic acid) have been synthesized and characterized by single-crystal X-ray diffraction methods (CIF files CCDC nos. 1432836 (I), 1432835 (II), 817411 (III), and 817412 (IV)), elemental analyses, IR spectra. Structural analyses reveal that compounds I, II, and IV have similar structures [Cu(Bpca)]⁺ units bridged by dicarboxylate forming dinuclear units, whereas the dinuclear of compound III are edge-shared through two carboxylate oxygen atoms of different suberate anions. Hydrogen bonds are response for the supramolecular assembly of compounds I to IV. The temperature-dependent magnetic property of III was also investigated in the temperature range of 2 to 300 K, and the magnetic behaviour suggests weak antiferromagnetic coupling exchange.     

Three metal complexes based on tetrazolyl ligands: Hydrothermal syntheses,crystal structures,and fluorescence properties

Three new complexes based on 1-tetrazole-4-imidazole-benzene (Tibz), namely, [Cd(Tibz)₂(H₂O)₂] _n (I), [Mn(Tibz)₂(H₂O)₄] · 2H₂O (II) and [Co(Tibz)₂(H₂O)₄] · 2H₂O (III) have been synthesized through hydrothermal method and structurally characterized by element analyses, IR spectroscopy and single-crystal X-ray diffraction analyses (CIF files CCDC nos. 1443867 (I), 1443868 (II), 1443869 (III)). Single-crystal X-ray diffraction reveals that complex I is a 1D double-chain architecture, II and III are both mononuclear complexes. The results of single-crystal X-ray diffraction analyses indicate that the hydrogen bond and π··· π stacking exist in the complexes, which make great contribution to the stabilities of complexes I–III. The fluorescent properties of these complexes have also been studied in the solid state at room temperature.     

Syntheses,structures and properties of complexes of indole-3-propionic acid

Three complexes [Zn₂(IPA)₂(phen)₄](HIPA)₂(NO₃)₂·H₂O (1), {[Zn(IPA)₂(bipy)]·3H₂O}_n (2), and {[Mn(IPA)₂(bipy)(H₂O)]·2H₂O}_n (3) (HIPA = indole-3-propionic acid, phen = 1,10-phenanthroline, bipy = 4,4′-bipyridine) were synthesized and characterized by physico-chemical and spectroscopic methods. Complex 1 displays a zero-dimensional structure, whilst 2 and 3 show one-dimensional chains, which are linked into supramolecular networks through hydrogen bonding interactions and/or π···π stacking interactions. The luminescence properties of complexes 1 and 2 were investigated.     

Topological insights in polynuclear Ni/Na coordination clusters derived from a schiff base ligand

This article presents the syntheses, crystal structures, topological features and magnetic properties of two Ni^II/Na^I coordination clusters formulated [Ni ₃ ^II Na(L1)₃(HL1)(MeOH)₂] (1) and [Ni ₆ ^II Na(L1)₅(CO₃)(MeO)(MeOH)₃(H₂O)₃]·4(MeOH) 2(H₂O) [2 4(MeOH) 2(H₂O)] where H₂L1 is the semi-rigid Schiff base ligand (E)-2-(2-hydroxy-3-methoxybenzylideneamino)-phenol). Compound 1 possesses a rare Ni ₃ ^II Na^I cubane (3M4-1) topology, and compound 2 is the first example in polynuclear Ni/Na chemistry that exhibits a 2,3,4M7-1 topology.     

Co(II) and Ni(II) complexes with imidazole-containing ligands: Synthesis,structural characterization,and magnetic property

Hydrothermal reaction of Co(II) salt with 1,4-di(1-imidazolyl)benzene (L¹) and 4,4’-oxydiphthalic acid (H₄OA) yields a new complex [Co₃(HOA)₂(L¹)₄(H₂O)₄] (I). [Ni(L²)₂SO₄] · 0.5H₂O (II) can be obtained via the hydrothermal reaction of NiSO₄ · 6H₂O with 1,3-di(1H-imidazol-4-yl)benzene (L²). Complexes I and II have been characterized by single-crystal and powder X-ray diffraction (CIF files CCDC nos. 1019291 (I) and 1019292 (II)), IR, elemental, and thermogravimetric analyses. Complex I exhibits the uninodal six-connected 3D pcu framework structure of I with (4¹² · 6³) topology; Complex II consists of the uninodal four-connected 2D sql (4⁴ · 6²) networks. In addition, magnetic property of I was investigated.     

Influence of anions on copper(II) complexes of a flexible bis-pyridyltrazole ligand: identification of a discrete water–chloride cluster [(H<Subscript>2</Subscript>O)<Subscript>10</Subscript>(Cl)<Subscript>8</Subscript>]<Superscript>8−</Superscript>

Three Cu(II) complexes, [Cu(H₂L)(ClO₄)₂] (1), [Cu(H₂L)_0.5(µ-SO₄)(H₂O)]·H₂O (2) and [{Cu(H₂L)(H₂O)}{Cu(H₂L)(Cl)]Cl₃·4H₂O (3), with a flexible ligand 1,2-bis(5-(pyridine-2-yl)-1,2,4-triazole-3-yl)ethane (H₂L) were synthesized from various Cu(II) salts. X-ray crystal structure analysis reveals that the H₂L ligand demonstrates different coordination modes in each of these complexes. Complex 1 shows a mononuclear structure with ClO₄ ^? anions weakly coordinated to the metal center, which is further extended into a 1-D assembly through hydrogen bonds. Complex 2 is a polymeric species in which the dinuclear units [Cu₂(H₂L)(H₂O)₂] are linked through SO₄ ^2? anions to form 1-D chains, which are further associated into a 2-D assembly through a self-assembled decameric water cluster. Complex 3 features an interesting 3-D coordination architecture assembled through extensive hydrogen interactions between chloride anions and water molecules. Notably, a unique discrete water–chloride cluster [(H₂O)₁₀(Cl)₈]^8? built around a chair-like water–chloride octameric core is identified in the crystal matrix of complex 3. The choice of counteranion plays a key role in the diverse structures of these complexes. The spectroscopic properties of the complexes have also been investigated.     

Syntheses,Crystal Structures and Luminescent Properties of Drum and Ladder-Like Organooxotin Clusters with Carbazole Ligand

Four new Organooxotin Clusters: [(p-MeC₆H₄)Sn(O)L¹]₆ (1) (HL¹ = 2-(9H-carbazol-9-yl)acetic acid), [PhSn(O)L²]₆·2C₆H₆·2H₂O (2) (HL² = 3-(9H-carbazol-9-yl)propanoic acid), [n-BuSn(O)L²]₆ (3), [(c-Hex₂Sn)₂(L¹)O(OH)]₂·3C₆H₆ (4), were synthesized with benzene being used as solvent in the reaction and characterized by elemental analysis, IR, NMR spectroscopy and X-ray crystallography diffraction analyses. Complexes 1–3 are hexanuclear organotin complexes with drum structure. Complex 4 is dimeric carboxylate tetraorganodistannoxane and shows a ladder structure. There are four crystallographically unique Sn centers in the structure of 4, which consists of a Sn₄O₂(OH)₂ ladder unit, and the ladder consists of four tins held together by four µ₃-oxygens. All the complexes show an extensive supramolecular organization in the solid state and form 1D or 2D supramolecular assembly mediated by C–H…O, C–H…π or π…π interactions. Moreover, complexes 1 and 4 exhibit good fluorescence properties in the solid state revealed by the luminescent investigation. The experimental results show the complexes may be explored for potential luminescent materials.     

Four supramolecular transition metal(II) complexes based on triazole-benzoic acid derivatives: crystal structure,Hirshfeld surface analysis,and spectroscopic and thermal properties

Four new complexes [M(3-tba)₂(H₂O)₄] (1–3) and [Co(4-tba)₂(H₂O)₄] (4) {M = Zn (1), Ni (2), Co (3), 3-Htba = 3-(1H-1,2,4-triazol-1-yl)benzoic acid, 4-Htba = 4-(1H-1,2,4-triazol-1-yl)benzoic acid} have been synthesized under solvothermal conditions and structurally characterized by single crystal X-ray diffraction. Complexes 1–4 are also determined by elemental analysis, X-ray powder diffraction, IR and electronic spectroscopy. Single crystal X-ray diffraction reveals that complexes 1–3 are isostructural and they crystallize in the orthorhombic space group of Pbca, while complex 4 belongs to triclinic system with Pī space group. Based on different intermolecular hydrogen bonding and π···π stacking interactions, complexes 1–4 further assembled into 3D supramolecular frameworks. Hirshfeld surface analysis was used to further study the intermolecular interactions of the complexes. The thermogravimetric analyses (TGA) reveal that these complexes possess good thermal stability, and the differential scanning calorimetry (DSC) analyses show intense exothermic phenomena in the decomposition processes of triazole groups. Besides, the photoluminescence property of complex 1 in the solid state is also determined.     

Zn-containing double complex salts formed by Keggin type polyoxotungstates: Synthesis and crystal structure

Novel double complex salts, [Zn(DMF)₆]₂[SiW₁₂O₄₀] · 2H₂O (I) and [Zn(H₂O)₂(DMF)₄][Zn(DMF)₆]₂[PW₁₂O₄₀]₂ · 6DMF (II) (DMF = N,N-dimethylformamide), were prepared by the reaction of Zn²⁺ and heteropoly acids H_x[EW₁₂O₄₀] · xH₂O (E = P, X = 3, E = Si, X = 4) in DMF. Compounds I and II were studied by X-ray diffraction (СIF files CCDC nos. 1497570 (I) and 1497571 (II)) and IR spectroscopy.     

Synthesis,structures and magnetic properties of four 3D heterometallic cobalt(II)–barium(II) coordination polymers

Four heterometallic complexes, namely {[CoBa(2,5-pdc)₂(H₂O)₃]_n·2nH₂O} (1), [CoBa(2,5-pdc)₂(H₂O)₄]_n (2), [CoBa(2,5-pdc)₂(H₂O)₅]_n (3) and [CoBa₂(2,5-pdc)₃(μ₂-H₂O)₂(H₂O)₄]_n (4) (2,5-H₂pdc?=?pyridine-2,5-dicarboxylic acid), have been hydrothermally synthesized and characterized both structurally and magnetically. All four complexes exhibit 3D frameworks, in which the Co(II) centers are chelated by pyridine nitrogen and carboxyl oxygen atoms in a five-membered ring. The Ba(II) centers are chelated and bridged by carboxyl oxygen atoms to extend the structures into 3D frameworks. The networks of the complexes can be controlled via rationally choosing the appropriate ligand and tuning the ratio of the two types of metal centers. The magnetic properties of complexes 1, 2 and 4 have been investigated from 2 to 300 K.     

Synthesis,crystal structures,and luminescent properties of three cluster-based heterometallic and monometallic compounds

Two heterometallic cluster compounds and one monometallic cluster compound, namely [Ni₉Co₆(PMIDA)₆(BTC)₂(H₂O)₁₂]·6H₂O (1), [Co₁₃Zn₂(PMIDA)₆(H₂O)₁₈]·6NO₃·15H₂O (2), and [Fe₁₅(PMIDA)₆(BTC)₂(H₂O)₂₂]·38H₂O (3), have been obtained under hydrothermal conditions using N-(phosphonomethyl)imino-diacetic acid (H₄PMIDA) and 1,3,5-benzenetricarboxylate acid (H₃BTC) as ligands, and structurally characterized by X-ray crystallography. Compound 1 exhibits a 3D open framework constructed from [Ni₉Co₆(PMIDA)₆(H₂O)₁₂]⁶⁺ heteronuclear clusters and BTC^3? ligands. Compounds 2 and 3 are both zero-dimensional polynuclear clusters, further extended into 3D supramolecular structures via hydrogen-bonding interactions. However, there are some differences in their crystal structures; compound 2 features an isolated spherical heteronuclear cation cluster based on PMIDA^4? ligands, such that the NO₃ ^? anions only balance the charge, whereas compound 3 is characterized as a neutral monometallic cluster incorporating two different types of organic acid ligands, namely PMIDA^4? and BTC^3?, and the two BTC^3? ligands exhibit regular distribution in each cluster. The luminescence properties of all three compounds have been investigated at room temperature.     

2,6-diformyl-4-<Emphasis Type="Italic">tert</Emphasis>-butylphenol bis-ferrocenoylhydrazone and binuclear copper(II) complexes on its basis

2,6-Diformyl-4-tert-butylphenol bis-ferrocenoylhydrazone (1, H₃L) and binuclear copper(II) complexes on its basis [Cu₂(H₂L)(OH)] (2), [Cu₂(H₂L)Cl₃]·(3), and [Cu₂(H₂L)(OH)]·₂NO₃ (4) have been synthesized and investigated. Tautomerism of bis-hydrazone (1) has been studied.     

Syntheses,characterization, and magnetic properties of two 3D frl topological frameworks constructed from nickel diphosphonates

Two 3D open-framework nickel diphosphonates, [Ni₃(H₂zdn)₂(bpe)₂]·4H₂O (1) and [Ni₃(H₂zdn)₂(bpy)₂]·bpy·4H₂O (2) (H₅zdn = zoledronic acid, bpe = trans-4,4-vinylenedipyridine, bpy = 4,4′-dipyridyl), have been prepared and structurally characterized. In complex 1, the metal centers are linked by zoledronate ligands to generate a 2D layer, containing 14- and 24-membered rings. These 2D layers are further pillared by the bpe ligands into a 3D network structure with cylindrical channels. Magnetic susceptibility measurements reveal ferrimagnetism at T _c = 3.8 and 4.4 K for complexes 1 and 2, respectively.     

Effect of N-donor sites of bis-pyridyl-bis-amide ligands on the architectures of three Anderson-type polyoxometalate-based metal–organic complexes

Three polyoxometalate-based metal–organic complexes [Co₂(H₂O)₆(TeMo₆O₂₄)](3-H₂dpyb)·2H₂O (1), [M₂(4-Hdpyb)₂(H₂O)₆(TeMo₆O₂₄)]·6H₂O [M = Co (2), Zn (3); 3-dpyb = N,N′-bis(3-pyridinecarboxamide)-1,4-butane, 4-dpyb = N,N′-bis(4-pyridinecarboxamide)-1,4-butane] have been hydrothermally synthesized and characterized by elemental analysis, IR, TG, powder diffraction and single-crystal X-ray diffraction analysis. The structure of complex 1 consists of 1D [Co₂(H₂O)₆(TeMo₆O₂₄)] inorganic chains, which are joined together by the 3-dpyb ligands through weak hydrogen bonds to generate a 2D supramolecular network. Complexes 2 and 3 are isostructural; each [TeMo₆O₂₄]^6? (TeMo₆) polyoxoanion chelates either two cobalt or two zinc atoms to generate the discrete complexes [Co₂(4-Hdpyb)₂(H₂O)₆(TeMo₆O₂₄)] and [Zn₂(4-Hdpyb)₂(H₂O)₆(TeMo₆O₂₄)], respectively. The electrochemical properties, electrocatalytic and photocatalytic activities of the complexes have been investigated.     

Deca(hydroxo)-23-aqua-hexa(lanthanum(III)) iodide octahydrate and deca(hydroxo)-23-aqua-hexa(neodymium(III)) iodide octahydrate: Syntheses and structures

New hexanuclear complexes of lanthanum and neodymium iodides, [La₆(H₂O)₂₃(OH)₁₀]I₈ · 8H₂O (I) and [Nd₆(H₂O)₂₃(OH)₁₀]I₈ · 8H₂O (II), are synthesized and studied by X-ray diffraction analysis. The isostructural crystals of complexes I and II are orthorhombic: a = 13.197(4) Å, b = 15.152(3) Å, c = 15.302(4) Å and a = 13.060(4) Å, b = 14.967(5) Å, c = 15.098(4) Å, respectively; Z = 2, space group Pnnm. The lanthanum (neodymium) atoms coordinate the aqua and hydroxo ligands and enter the composition of the Ln₆ -containing complex cations. The coordination polyhedron (ignoring the central oxygen atom) of each atom of the complexing agent is somewhat distorted square antiprism with the aqua and hydroxo ligands being in the vertices. Four bridging ligands link this atom of the complexing agent with the four adjacent atoms.     

Comprehensive comparison between the reaction of <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>'-cyclohexane-1,2-diylidene-bis(4-methoxybenzoylhydrazide) with mercury(II) and copper(II) ions. Synthesis,structure, and kinetics of complex formation

Comprehensive comparison between the reaction of N,N'-cyclohexane-1,2-diylidene-bis(4-methoxybenzoylhydrazide) (CHMBH) with HgCl₂ and Cu(NO₃)₂ · 2.5H₂O salts have been investigated, including the synthesis, structure and kinetic of complex formation. The reactions of CHMBH with HgCl₂ or Cu(NO₃)₂ · 2.5H₂O at the same synthetic conditions have been shown to produce completely different type of complexes: [Hg(CHMBH)Cl₂] · CH₃CN (I) and [Cu₃(μ₃-OH)(CTMB)₃(NO₃)₂(CH₃CN)₂] · 5CH₃CN · H₂O (II) (CTMB = cyclohexotriazole-3-(4-methoxybenzamide)). The prepared compounds were characterized using different techniques (NMR, IR, UV-Vis and mass spectroscopies, microelemental analysis, thermogravimetry as well as X-ray powder differection and X-ray single crystal crystallography for I (CIF file CCDC no. 1503398). X-ray crystallography shows that the isolated product of I is a mononuclear complex which contains the [Hg(CHMBH)]²⁺ core. While, the isolated product of II was a trinuclear Cu(II) cluster [Cu₃(μ₃-OH)(CTMB)₃(NO₃)₂(CH₃CN)₂] · 5CH₃CN · H₂O which contains three differently coordinated copper sites. Kinetic studies on the formation of I have been also investigated and compared with that of II. In case of I, the reaction was so slow and exhibits a first-order dependence on the concentration of metal salt and a first-order dependence on the concentration of CHMBH. While in II, the study shows that the reaction is fast and occurs in three distinct phases.     

One Novel 3D Supramolecular Network Based on Dicobalt-Carboxylate Secondary Building Units with Polycarboxylate Ligands 1, 2, 3, 4-Butanetetracarboxylic Acid

A novel cobalt–carboxylate framework constructed from secondary building units (SBUs), {[Co₁₆(btca)₈(H₂O)₄₀]·16H₂O}_n (1) (H₄btca = 1,2,3,4-butanetetracarboxylic acid) has been hydrothermally synthesized and characterized by techniques of single-crystal X-ray diffraction analyses, elemental analyses, infrared spectra, powder X-ray diffraction and thermogravimetric analyses. The complex exhibits 2D 4-connected sql net with (4⁴ × 6²) topology symbol built from [Co₂(COO)₄(H₂O)₅] SBUs and is further extended into a 3D supramolecular architecture via strong O–H···O hydrogen bonds. Moreover, the magnetic measurements indicate complex 1 exhibit antiferromagnetic behavior.     

Synthesis,characterization, and biological activity of Cd(II) and Mn(II) coordination polymers based on pyridine-2,6-dicarboxylic acid

The coordination polymers (CPs) {[Cd(Pydc)(H₂O)₃] · PydcH₂} (I) and [Mn(Pydc)(H₂O)₃] · PydcH2} (II) were obtained by the reaction of CdSO₄ · 5H₂O or MnCl₂ · 4H₂O with pyridine-2,6-dicarboxylic acid (PydcH₂). The structures of the CPs I and II were characterized by IR, UV-Vis, TGA, and X-ray single crystal analysis (CIF files CCDC nos. 1417757 (I), 1417758 (II)). The network structures of I and II are constructed by an infinite number of discrete binuclear molecules and free PydcH2. The structures of the CPs I and II connected by the extensive H-bonds and π–π stacking, forming a 3D-network. The CPs I and II were screened to test their antimicrobial activities against different species of bacteria and fungi.