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[Display omitted] • The crystal structure of new mononuclear, mixed-ligand Co(II) complex is determined. • The maximum adsorption capacity of the complex reached 194.4 mg/g for Rhodamine B dye. • The plausible mechanism is electrostatic interaction, hydrogen bonding, and π-π interaction. • The kinetic study investigation provided, Q e = 207.3 mg/g. A new mixed-ligand cobalt complex with the general formula [Co(H 2 O)(teaH 3)(4-NBA)]·(4-NBA)·H 2 O (1), where (teaH 3 = triethanolamine and 4-NBA = 4-nitrobenzoate), has been successfully synthesized and characterized. In this complex, triethanolamine acts as a tetradentate ligand and the 4-NBA act as monodentate ligands. The cobalt metal ion in the complex has a coordination number of 6 with a slightly distorted octahedral geometry. Furthermore, some intramolecular and intermolecular interactions have been observed in 1. Moreover, the kinetic studies on the rate of adsorption confirm that the Pseudo Second Order model accurately predicted the absorption of RhB by the complex. The higher R-squared value and the close agreement between the calculated (Q e = 207.3 mg/g) and experimental (194.4 mg/g) values indicate a satisfactory match. The hydrogen bonding interactions and other weaker electrostatic interactions between the complex and the RhB molecule enhance this adsorption. [ABSTRACT FROM AUTHOR]

In this work, a sulfonated UiO-66 was synthesized and modified with a mixed ligand strategy using 2-amino terephthalic acid as a second linker. The X-ray diffraction (XRD) diffractogram shows a transition from an amorphous to a crystalline pattern with the addition of a second linker. The Fourier transforms infrared spectroscopy spectra show the presence of new peaks at 1255, 1382, and 1426 cm−1, which refer to N-H and C-N stretching. All the mixed ligand samples showed stable thermal stability as the pristine UiO-66-SO 3 H sample. The field emission scanning electron microscopy analysis also showed a morphological change from a round-like shape (UiO-66-SO 3 H) to a triangular-based pyramid shape (UiO-66-SO 3 H-NH 2 -0.85). The nitrogen physisorption analyses showed a significant increase in the BET surface area of UiO-66-SO 3 H-NH 2 -0.85 (706 m2/g) from UiO-66-SO 3 H (16 m2/g). The CO 2 -TPD results demonstrated that the greater formation of medium basic sites (monodentate carbonate and bidentate carbonate species) is due to the increase in the amount of the second linker. Furthermore, the UiO-66-SO 3 H-NH 2 -0.85 showed CO 2 adsorption of 2.17 mmol/g, five times higher than UiO-66-SO 3 H (0.43 mmol/g). Both samples also showed excellent recyclability up to ten cycles. After being reused for ten cycles, the sample preserved the characteristics of the XRD pattern and crystallinity, functional groups, and thermal stability. For the water and pH stability studies, UiO-66-SO 3 H and UiO-66-SO 3 H-NH 2 -0.85 maintained the original XRD patterns, a high BET surface area, and good CO 2 adsorption in water and acid environments. [Display omitted] • Introducing the amino group as a second linker into UiO-66-SO 3 H is an efficient approach. • The highest CO 2 adsorption was observed on UiO-66-SO 3 H-NH 2 -0.85 of 2.17 mmol/g at 25 ˚C and 1 atm. • UiO-66-SO 3 H and UiO-66-SO 3 H-NH 2 -0.85 maintain the recyclability for up to ten cycles. • BET surface area and polar functional groups played important roles in CO 2 adsorption performance. • UiO-66-SO 3 H and UiO-66-SO 3 H-NH 2 -0.85 showed good water and chemical stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel mixed imidazole ligand MIL-88A was proposed and prepared for the first time. • The photocatalyst revealed significantly smaller particle size and greatly improved photocatalytic capacity. • 100% decomposition of 100 ppm AR1 dye was achieved within 45 min of irradiation with the assistance of a trace amount of H 2 O 2. • A dye removal rate of 99.98% was maintained after five cycles. • Photo-generated h+ was the main oxidizing specie in the photocatalytic reaction. In this study, we fabricated MIL-88A metal–organic frameworks with excellent physicochemical properties using mixed organic ligands. In addition, we investigated the effects of different iron precursors on the physicochemical properties of the as-prepared MIL-88A samples. We determined that the difference between the dissociation rates of the metal ions of different iron precursors affected the crystallization rate of MIL-88A, which effectively decreased particle size, causing an increase in the adsorption capacity of MIL-88A and significantly improving its photocatalytic activity. Two organic ligands: 2-methylimidazole and fumaric acid, were mixed, and the formed dihydrate affected the crystallization rate of MIL-88A; moreover, the as-fabricated MIL-88A presented small particle size and high oxidation potential. The as-prepared mixed organic ligand MIL-88A removed 96.42% of AR1 dye from an AR1 dye solution with a concentration of 20 mg/L after 2 h of irradiation. Furthermore, an AR1 dye removal of 100% was achieved after only 45 min of irradiation using a 100 mg/L AR1 dye solution in the presence of trace H 2 O 2. The decomposition efficiency of MIL-88A did not decrease after five removal cycles, and this was attributed to the excellent decomposition efficiency of MIL-88A with mixed organic ligands, which was ascribed to its remarkable adsorption capacity and high oxidation potential. Strong oxidizing hydroxyl radicals were generated via a photo-Fenton reaction to improve the oxidative power of MIL-88A, and pollutants were decomposed without generating residues. We believe that these findings can be used to significantly expand the application of MIL-88A in photocatalysis research. [ABSTRACT FROM AUTHOR]

Abstract The new series of divalent metal complexes [M(ox)(thy) 2 ]; M = Cd2+, Ni2+, Mn2+, Fe2+, Cu2+ and Zn2+, with mixed ligands oxalato (ox) and theophylline (thy) were prepared and characterized by molar conductance, FT-IR, UV–visible, 1H and 13C NMR and X-ray structure analysis. The crystal structure including the positions of the Zn (II) complex was determined by powder diffraction analysis using the FOX program. In the structure of zinc complex, the zinc (II) cations are octahedrally coordinated by two terminals N-bonding for theophylline ligand and by the O atoms of two oxalato bidentate ligand, resulting in discrete and slightly distorted octahedral complex. This complex was crystallized in the monoclinic system (C1 2/c1) space group and the unit cell parameters are a = 11.8364(1)Å, b = 4.5200(1)Å, c = 9.9942(1)Å with β (°) = 126.4770(2)°. The antimicrobial activity of the complexes was studied and the results of their tests show that the metal (II) complexes are more effective against several of bacterial and fungal strains. Graphical abstract Image Highlights • Six new complexes of general formula:[M (ox)(thy) 2 ] were synthesized. • The characterization of the synthesized complexes was investigated. • The octahedral structure of the obtained complexes was checked. • The antibacterial activity of the complexes was tested. [ABSTRACT FROM AUTHOR]

Abstract Two novel mixed-ligand complexes of lead(II), [Pb(Cup) 2 (Phen)] 2 ](DPE) (1) and [Pb(Cup)(ONO 2)(Phen)] (2) (Cup = cupferronato, Phen = 1,10-phenanthroline, and DPE = 1,2-di(4-pyridyl)ethylene), were synthesized in the presence of common bridging ligands which are usually used in synthesis of lead(II) coordination polymers as well as utilization of Cup and Phen as O,O′- and N,N′- chelates, respectively. Structural features of 1 and 2 in solution were investigated by 1H and 13C NMR experiments. The accurate assignment of these signals was inferred from a series of 1H–1H COSY, 1H–13C HSQC, and 1H–13C HMBC spectra. The solid-state structures of 1 and 2 were also investigated via single crystal XRD. By considering the obtained structural parameters, the coordination of 1 is hemidirected while 2 is suggested to be holodirectional. Additionally, complex 1 consist of dimers which are further associated via π-π stacking to a one-dimensional coordination polymer while complex 2 forming a step-like one-dimensional chain by an intermolecular interaction between each molecule and two nitrato groups of the two adjacent molecules. Both complexes showed significant antibacterial and antifungal characteristics in disc diffusion tests and they could be considered as new potent antimicrobial material. Graphical abstract Image 1 Highlights • Two novel mixed-ligand complexes of lead(II) were prepared. • The structures in solution were investigated by different NMR spectroscopies. • The molecular structures showed hemidirected and holodirected coordinations. • 1 consists of associated dimers via π-π stacking and forms 1D coordination polymer. • Complex 2 forms a step-like one-dimensional chain. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The mixed-ligand binuclear complexes [Co 2 (BIBP)(2,6-PDC) 2 (H 2 O) 4 ] (1), [Ni 2 (BIBP)(2,6-PDC) 2 (H 2 O) 4 ] (2), and the coordination polymers 1D-{[Zn(BIBP)(2,6-PDC)]·4.5H 2 O} n (3), 2D-[Ni 2 (BIBP)(2,5-PDC) 2 (H 2 O) 4 ] n (4), and 3D-{[Ni 2 (BIBP) 3 (2,3-PDC) 2 ]·3.75H 2 O} n (5) were synthesized in good yields, characterized by IR, thermogravimetry and single X-ray diffraction method (BIBP = 4,4′-bis(1-imidazolyl)biphenyl, 2,6-PDC = 2,6-pyridinedicarboxylate, 2,3-PDC = 2,3-pyridinedicarboxylate, 2,5-PDC = 2,5-pyridinedicarboxylate). Compounds 1 and 2 are binuclear complexes, compound 3 is a 1D polymer, 4 has a 2D laminated structure, and 5 represent a 3D framework. A common motif in the structures, independent of their dimensionality is the bridging action of the neutral BIBP ligand between two metal ions and a metal chelating coordination of the dianionic PDC ligand through the pyridine nitrogen atom and the carboxylate group in 2-position. The comparative single crystal X-ray structure investigations reveal the fine-tuning influence of the carboxylic group positions in the pyridinedicarboxylate (PDC) ligands and the metal nature on the final structure topology and dimensionality. Compounds 1 and 2 are isostructural and represent Co(II) and Ni(II) isomorphs, where the metal ions coordinate two water molecules and the 2,6-PDC ligand in ONO chelate mode, while the bidentate BIBP ligand link the metal ions into a dinuclear complex. In 3 the 2,6-PDC ligand coordinates to the zinc atom in the same ONO chelate mode and two bridging BIBP ligands give a coordination number of five and extend the structure to a 1D polymer with an enantiopure triple-stranded helix motif in a case of spontaneous resolution in the chiral tetragonal space group P 4 3 22. In 4 the 2,5-PDC ligand realises its chelate-bridging function and together with the bridging BIBP ligand form 2D layers with the Ni(II) atoms with hcb (honeycomb or 6,3) topology. In 5 the chelate-bridging 2,3-PDC and BIBP ligands form (4,4)-layers which are interlinked by additional BIBP pillars to a 3D network with two-fold interpenetration of symmetry-related networks. [ABSTRACT FROM AUTHOR]

Five Ag(I) coordination complexes, namely, [Ag 6 (2-stp) 2 (3-methyl-2-apy) 3 ·H 2 O] n ( 1 ), [Ag 3 (2-stp)(4-methyl-2-apy) 3 ] n ( 2 ), [Na 2 Ag 18 (2-stp) 4 (2-Hstp) 4 (5-methyl-2-apy) 16 (H 2 O) 4 ·11H 2 O] n ( 3 ), Ag 3 (2-stp)(6-methy-2-apy) 4 ·H 2 O ( 4 ), and [Ag 6 (2-stp) 2 (6-methyl-2-apy) 8 (H 2 O) 2 ·H 2 O] n ( 5 ) (2-NaH 2 stp = 2-sulfoterephthalic acid monosodium salt, 3-methyl-2-apy = 3-methyl-2-aminopyridine, 4-methyl-2-apy = 4-methyl-2-aminopyridine, 5-methyl-2-apy = 5-methyl-2-aminopyridine, 6-methyl-2-apy = 6-methyl-2-aminopyridine), have been synthesized and structurally characterized. Complexes 1 and 2 show two-dimensional network. In complex 3, the adjacent Ag 10 units are bridged by 5-methyl-2-apy ligands to form a 2D infinite undulated sheet. Adjacent 2D sheets are linked by coordinative bonds between carboxylic oxygen atoms and Na(I) ions to form a 3D coordination polymer. Complex 4 is a 0-D discrete trinuclear molecule, and the self-complementary the O H⋯O and N H⋯O hydrogen bonds incorporating hydrogen bond motifs extend these molecules into a 2D supramolecular framework. Compound 5 exhibits 1D-chain structure. However, complex 5 shows 3D supramolecular structure results from the linkage of neighboring layers through a rich hydrogen-bonding between uncoordinated sulfonates, amino groups and coordinated carboxylates. The thermogravimetric analyses and photoluminescence of the complexes were also investigated. [ABSTRACT FROM AUTHOR]

The mixed-ligand coordination polymers {[Zn(BIX) 2.5 ](NO 3 ) 2 ·5.5H 2 O} n ( 1 ), {[Co(BIX)(HBTC)](BIX) 0.5 ·H 2 O} n ( 4 ), [Ni(BIX) 2 (BDC)(H 2 O)] n ( 5 ), [Zn(BIX)(PDC)] n ( 6 ), [Ni(BIX)(PDC)(H 2 O)] n ( 7 ) and [Zn(BIX) 0.5 (HIDC)] n ( 8 ) were synthesized, structurally characterized and compared to the known coordination polymers {[Co(BIX) 3 ](NO 3 ) 2 ·4H 2 O} n ( 2 ) and {[Zn 2 (BIX)(BTC)(OH)]·H 2 O} n ( 3 ) to determine the mutual influence of an anionic carboxyl ligand and a neutral N-donor ligand (BIX = 1,4-bis((1H-imidazol-1-yl)methyl)-benzene; H 3 BTC = 1,2,3-benzene-tricarboxylic acid; H 2 BDC = 1,3-benzene-dicarboxylic acid (isophthalic acid); H 2 PDC = 3,4-pyridine-dicarboxylic acid; H 3 IDC = 4,5-imidazole-dicarboxylic acid). Compound 1 is a 1D ladder-like structure with two bridging and one terminal (dangling) BIX ligand. Neighboring ladders mutually entangle with the dangling BIX ligand being threaded through {Zn 4 (BIX) 4 } openings from adjacent strands. Compound 2 shows a 3D pcu -network with octahedrally coordinated cobalt ions bridged by three crystallographically different inversion-symmetric BIX ligands. The overall structure motifs in the mixed-ligand compounds are 1D metal-carboxylate chain-structures, bridged by neutral BIX ligands to form either 1D ladder-like strands ( 4 ), 2D networks ( 3 , 5 with square lattice, 4,4 or sql topology, 7 , 8 with honeycomb, 6,3 or hcb topology) or 3D frameworks ( 6 with diamond, 6,6 or dia topology). Noteworthy, compound 4 forms a 1D tubular structure of stacked {Co 2 (BIX) 2 } metallacycles that are threaded with uncoordinated BIX ligands like a rotaxane. A tetrahedral asymmetric Zn atom is formed in the crystals of 6 with spontaneous resolution as only one Zn configuration assembles into the 3D chiral framework of each single crystal. [ABSTRACT FROM AUTHOR]

The hydrothermal reaction of K 8 Na 2 [A-α-GeW 9 O 34 ]·25H 2 O, Cu(CH 3 COO) 2 ·H 2 O, Ln(NO 3 )·6H 2 O and ethylenediamine (en) has led to a series of inorganic–organic hybrid copper–lanthanide heterometal comprising germanotungstates (GTs) [Cu(en) 2 (H 2 O)] 6 [Ln(H 2 O)(CH 3 COO)(α-GeW 11 O 39 )] 2 ·8H 2 O [Ln = Nd 3+ ( 1 ), Sm 3+ ( 2 ), Eu 3+ ( 3 ), Gd 3+ ( 4 ), Dy 3+ ( 5 ), Ho 3+ ( 6 )], which have been characterized by elemental analyses, IR spectra, thermogravimetric (TG) analyses and single-crystal X-ray diffraction. Their common feature of 1 – 6 is that they all comprise a CH 3 COO-bridging mono-Ln substituted dimeric GT fragment [Ln(H 2 O)(CH 3 COO)(α-GeW 11 O 39 )] 2 12− with six supporting [Cu(en) 2 (H 2 O)] 2+ complex cations. To the best of our knowledge, such monovacant Keggin-type GTs containing both Cu–Ln heterometal centers and mixed en and acetate ligands are very rare. The luminescence properties and the lifetime decay behavior of the solid sample of 3 have been intensively investigated at room temperature. [ABSTRACT FROM AUTHOR]

A new stable cobalt-organic framework, namely [Co 2 (oba) 2 (H 2 Me 4 bpz)] n ( 1 ) (H 2 oba = 4.4′-oxydibenzoic acid, H 2 Me 4 bpz = 3.3′,5,5′-tetramethyl-4,4′-bipyrazole), has been synthesized by combining the mixed H 2 oba and H 2 Me 4 bpz with Co(CH 3 COO) 2 ·4H 2 O under solvothermal conditions, which was characterized by infrared spectroscopy, single-crystal X-ray diffraction, powder X-ray diffraction, and thermogravimetric analyses. Single-crystal X-ray diffraction analysis reveals that 1 features a three-dimensional framework, which is built from interesting tetrahedral cages. The thermal stability of the complex has also been investigated. [ABSTRACT FROM AUTHOR]

To determine the influence of metal ion and N-donor auxiliary ligands on the formation of metal–organic frameworks, four novel metal coordination polymers, [Cd(bdam)(phen) 2 ] n ( 1 ), [Cd(bdam)(bpy)] n · n H 2 O ( 2 ), [Zn(bdam)(bpy)] n · n H 2 O ( 3 ) and [Ag 4 (bdam) 2 (dpe)] n ( 4 ) (H 2 bdam = benzophenone-2,4′-dicarboxylic acid, bpy = 2,2′-bpyridine, phen = 1,10-phenanthroline, dpe = 1,2-(4-pyridyl)ethane) were synthesized and characterized. Complex 1 is 1D square-wave-like chain structure. Two phen ligands chelate to one cadmium atom in 1 . 2 shows 1D ring chain based on dinuclear cadmium unit linked by (bdam) 2− ions, while two 2,2′-bpy ligands coordinate one dinuclear cadmium unit. 3 forms a 1D right-handed helical chain. Different from the above complexes, 4 possesses a 2D network structure based on octanuclear silver clusters cross-linked by bdam 2− ions and dpe ligands, in which there is significantly Ag⋯Ag interactions. The structural differences of 1 and 2 indicate that the subtle variations on N-donor ligands can greatly affect the coordination modes of (bdam) 2− ion and the coordination geometries of Cd II ion. The structural differences of 2 , 3 and 4 indicate that metal ions also have great influence on the structures of the complexes. In addition, we have investigated the luminescence of 1 – 4 in the solid state at room temperature, revealing that the polymers are photoluminescent and their emissions are varied with the alteration of metal ions and N-donor ligands. [ABSTRACT FROM AUTHOR]

With flexible 2-methylenesuccinate acid (H 2 MSA) and rigid 4, 4′-bipyridine (bpy) as mixed ligands, two three-dimensional (3D) metal−organic frameworks (MOFs), {[Zn 3 (μ 2 -OH) 2 (MSA) 2 (bpy) 2 ]·4H 2 O} n (1) and {[Cd(MSA)(bpy)]·2H 2 O} n (2), were obtained solvothermally. Complexes 1 and 2 both have a 3D framework structures, which include respectively a linear trinuclear [Zn 3 ] or a rare dinuclear [Cd 2 ] cluster node that consisting of two seven-coordinated Cd(II) ions. The adjacent [Zn 3 ] or [Cd 2 ] nodes in 1 and 2 are firstly linked together by the MSA2− ligand to form a 1D chain or a 2D layer unit respectively, which are further bridged by the bpy linkers to produce the 3D framework structures. If treating the [Zn 3 ] and [Cd 2 ] cluster as 4- and 6-connected nodes, the 3D frameworks of 1 and 2 can be simplified into a CdSO 4 topological network with a Schläfli symbol of (65.8) and a rob network with a Schläfli symbol of (48.66.8), respectively. The PXRD patterns suggest that 1 and 2 have good stability when soaked in water for at least 48 h. The fluorescence sensing properties of 1 and 2 toward different metal inorganic ions were investigated, and two complexes both could sense Fe3+, MnO 4 − and Cr 2 O 7 2− in aqueous solution with high sensitivity and selectivity (the LODs were 3.20 μM, 1.54 μM and 1.95 μM for 1 , 1.15 μM, 0.48 μM and 1.23 μM for 2 , respectively) as well as good recircularity. In addition, the mechanism of the selective luminescence quenching response for Fe3+, MnO 4 − and Cr 2 O 7 2− could be attributed to the energy competition between the excitation of complex 1 / 2 and the ultraviolet absorption of responsive substances. [Display omitted] • Two 3D luminescent MOFs were obtained by a strategy of rigid-flexible co-linkers. • The frameworks contain rare linear trinuclear [Zn 3 ] or dinuclear [Cd 2 ] cluster units respectively. • The complexes displayed good luminescent properties in water. • The complexes could behave as multi-target probes to sense Fe3+, MnO 4 − and Cr 2 O 7 2− with high sensitivity and selectivity. [ABSTRACT FROM AUTHOR]

Six mixed ligand complexes, namely, [Co(acac)L 1 ] ( 1 ), [Fe(acac)L 1 ] ( 2 ), [Co(acac)L 2 ] ( 3 ), [Fe(acac)L 2 ] ( 4 ), [Co(acac)L 3 ] ( 5 ), and [Fe(acac)L 3 ] ( 6 ) (H 2 L 1 = NN / -bis(salicylidene)-trans 1,2 diaminocyclohexane, H 2 L 2 = NN / -bis(salicylidene)-1,2 phenylenediamine, H 2 L 3 = NN / -bis(salicylidene)-4-methyl-1,2-phenylenediamine) were synthesised and characterized using elemental analysis, IR spectra, UV–Vis spectra, mass spectra, magnetic susceptibility measurements, 1 H and 13 C NMR spectroscopy, thermogravimetric analysis. The molar conductance measurement confirmed the non-electrolytic nature of the complexes in DMF solution. Antioxidant activity of the complexes was studied using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging method. Biological studies of the complexes have been carried out in vitro for antimicrobial activity against some selected gram-positive and gram-negative bacteria. DFT calculations were performed using GAUSSIAN 09 program to ascertain the stable electronic structure, HOMO-LUMO energy gap, chemical hardness and dipole moment of the complexes. [ABSTRACT FROM AUTHOR]

A new tetradentate N 4 -coordinate ligand N , N -bis(3,5-dimethyl-1H-pyrazol-1-yl)methyl-N 2 -phenylethane-1,2-diamine (bdpab) has been synthesized and characterized. Six new mononuclear mixed ligand complexes of the types [M(bdpab)(NCS)]Y [M = Cu(II) and Zn(II), Y = PF 6 − , ClO 4 − ], [M′(bdpab)(NCS) 2 ] [M′ = Co(II) and Ni(II)] have been synthesized by treating metal nitrate/perchlorate, tetradentate N 4 -coordinated ligand (bdpab), NCS − and PF 6 − ions using appropriate mole ratio and characterized by spectral and physico-chemical techniques. Crystal structures of four compounds [Cu(bdpab)(NCS)]ClO 4 , [Co(bdpab)(NCS) 2 ], [Ni(bdpab)(NCS) 2 ] and [Zn(bdpab)(NCS)]PF 6 have been solved by single crystal X-ray crystallography studies. Structural analyses reveal copper(II) and zinc(II) complexes have five coordination with distorted square pyramidal [for copper(II)] or trigonal bipyramidal [for zinc(II)] geometry whereas Co(II) and Ni(II) complexes have distorted octahedral geometry. [ABSTRACT FROM AUTHOR]

A series of novel salicylaldehyde (Sal) mixed ligand Mn(III) complexes of MnL NEX (Sal) containing bis(phenol) diamine ligands (H 2 L NEX ), have been prepared and their spectroscopic (IR, UV–Vis, ESI-MS), X-ray, magnetic and redox properties have been investigated. The X-ray crystallography analysis shows that all complexes are monomeric and every Mn(III) center is surrounded by four-dentate ligand and salicylaldehyde molecule. In addition, the geometric configurations of all complexes are slightly distorted octahedral. The temperature dependence of magnetic susceptibility of complexes confirms the mononuclear structure of complexes. Oxidation of the Mn(III) complexes yielded the corresponding Mn(III)-phenoxyl radical species during the cyclic voltammetry experiments. To the best of our knowledge, this is one the rare reports on salicylaldehyde coordination to manganese. [ABSTRACT FROM AUTHOR]

A new series of solvatochromic mononuclear mixed ligand chelates with the general formula: Cu(AcBL)(L)X; where AcBL = 2-acetylbutyrolactonate, L = N,N,N′,N′-tetramethylethylenediamine (Me 4 en), N,N,N′,N′-tetramethylpropylene diamine (Me 4 pn), 1,10-phenanthroline (Phen) or 2,2′-bipyridyl (Bipy) and X = ClO 4 − , NO 3 − or Br − have been synthesized and characterized by the analytical and spectral methods, as well as magnetic and molar conductance measurements. The d–d absorption bands of Me 4 en-chelates as Nujol mulls or weak donor solvents solutions revealed square-planar, distorted octahedral and/or distorted trigonal bipyramid geometries for the perchlorate, nitrate and bromide chelates, respectively. However, an octahedral structure is identified for chelates in strong donor solvents. Perchlorate chelates show a remarkable color change from violet to green as the Lewis basicity of the donor solvent increases, whereas bromide chelates are mainly affected by the Lewis acidity of solvent. Specific and non-specific interactions of solvent molecules with the chelates were investigated on the basis of unified solvation model. Structural parameters of the free ligands and their Cu(II)-chelates have been calculated on the basis of semiempirical PM3 level and correlated with the experimental data. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have emerged as new porous materials for capture and separation of binary gas mixtures. Tuning the metal sites in MOF structures has an impact on properties, which enhance affinity of gas adsorption and selectivity ( e.g. , surface area, cavity, electric field, etc .). The synthesis and characterization of a M-DABCO series (M = Ni, Co, Cu, Zn) of MOFs are described in this study. The experiments were conducted using multicomponent gas mixtures and the Ideal Adsorbed Solution Theory (IAST) was applied to determine the CO 2 /CH 4 selectivity. Experimental adsorption isotherms were fitted with a model equation to evaluate the characteristic adsorption energy (Isosteric, Qst) of this series. The Ni metal in the M-DABCO series reveals the best performance concerning CO 2 adsorption and CH 4 /CO 2 selectivity at ambient conditions based on IAST calculations. The combination of characterizations, calculations and adsorption experiments were used to discuss the metal impact on the adsorption sites in the M-DABCO series at ambient conditions. [ABSTRACT FROM AUTHOR]

A new mixed-ligand Zeolitic Imidazolate Framework Zn4(2-mbIm)3(bIm)5·4H2O (named JUC-160, 2-mbIm=2-methylbenzimidazole, bIm=benzimidazole and JUC=Jilin University China) was synthesized with a solvothermal reaction of Zn(NO3)2·6H2O, bIm and 2-mbIm in DMF solution at 180°C. Topological analysis indicated that JUC-160 has a zeolite GIS (gismondine) topology. Study of the gas adsorption and thermal and chemical stability of JUC-160 demonstrated its selective adsorption property for carbon dioxide, high thermal stability, and remarkable chemical resistance to boiling alkaline water and organic solvent for up to one week. [ABSTRACT FROM AUTHOR]

Highlights: [•] Complex 1 features 3D structure which consists of 1D helical silver chains. [•] Complex 2 possesses infinite silver chains with repeated Ag-triangle units. [•] Complex 3 exhibits 2D 44 - sql network with the 1D double chains. [•] Complex 4 shows Ag6 units in the 3D coordination network. [•] The photoluminescence behaviours of the complexes were discussed. [Copyright &y& Elsevier]

Abstract: Twenty one novel mixed ligand di-n-butyltin(IV) complexes [ n Bu2SnAL] (A = substituted 4-acyl-5-pyrazolone, and L = fluorinated benzoic acid) were prepared by condensation of di-n-butyltin(IV) oxide with HL and HA in 1:1:1 molar ratio in refluxing methanol. All of the complexes were characterized by elemental analyses, IR, NMR (1H, 13C, 119Sn) and in four cases by X-ray diffraction. Cytotoxicity of the compounds was studied against two human cancer cell lines (KB and Hela) by means of the MTT assay compared to cisplatin, featuring IC50 values in the low micromolar range. Hela cancer cell apoptosis-induced by 2 was examined by flow cytometry analysis, and preliminary results showed that 2 at concentrations of more than 1.0 μM can induce apoptosis. [Copyright &y& Elsevier]

Highlights: [•] Newer mixed ligand Schiff base complexes from aquo-N-(2′-hydroxy acetophenone) glycinatocopper(II) as synthon. [•] Versatility of the aquated Cu(II) complex as synthon has been demonstrated. [•] A distorted square planar geometry has been conjectured for the complexes from DFT calculation. [•] The complexes exhibited potent antibacterial activity correlated with docking scores. [Copyright &y& Elsevier]

Abstract: Reported here is a novel Cd(II) coordination polymer (namely [Cd(L1)0.5(ntd)]n (1), L1=N,N′-di(4-pyridyl)adipoamide, H2ntd2 =1,4-naphthalenedicarboxylic acid). Single-crystal X-ray diffraction reveals that the framework can be represented as metal/organic-binodal 4-connected Moganite net with three-fold interpenetration. Importantly, for the first time, an unusual coordination mode is observed for the acylamide ligand in such manner that every L1 ligand links four Cd(II) ions through two nitrogen atoms from two pyridine groups and two oxygen atoms from two acylamide groups. [Copyright &y& Elsevier]

Abstract: With the principles of crystal engineering, three novel metal(II) complexes, [Cu2(betd)(phen)4] . 15H2O (1), [Cd4(betd)2(phen)8]⋅28H2O (2) and {[Co2(betd)(phen)2(H2O)2]·2H2O}n (3) (H4betd=bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic acid, phen=1,10-phenanthroline) were synthesized and structurally characterized by elemental analyses, IR spectroscopy, single-crystal X-ray diffraction analyses, TGA, powder XRD and fluorescent measurements. Complex 1 is a binuclear structure, novel water tapes are observed to be encapsulated in the 3D open supramolecular architecture by hydrogen bond interactions. In 2, two pairs of CdII ions joined with two (betd)4− ions to form a cyclic tetranuclear structure. The neighboring tetranuclear units are linked into 2D network through π⋯π stacking interactions. Interestingly, the lattice H2O molecules are joined by strong hydrogen bond interactions generating a wavy water layer, which contacts the 2D network to form 3D supramolecular structure. 3 shows a 2D (4,4) grid network, which are assembled in an ABAB sequence to 3D supramolecular structures via π⋯π stacking interactions between two central phen ligands from two adjacent sheets and hydrogen bond interactions. [Copyright &y& Elsevier]

Abstract: Five Pd(II)-based potential potent metallopharmaceuticals (1–5) of the general formula [(DT)Pd(PR3)Cl], where DT=dibutyldithiocarbamate (1,2), dipropyldithiocarbamate (3), bis(2-methoxyethyl)-dithiocarbamate (4), dimethyldithiocarbamate (5); PR3 =triphenylphosphine (1), diphenyl-p-tolylphosphine (2), diphenyl-t-butylphosphine (3), diphenyl-2-methoxyphenylphosphine (4), p-cholorodiphenylphosphine (5), have been synthesized and characterized using FT-IR, Raman, and multinuclear-NMR spectroscopy. The X-ray single crystal analysis (1 and 2) reveals the Pd(II) moiety is in a distorted square–planar arrangement with two positions being occupied by the bidentate dithiocarbamate ligand, while the other two positions are occupied by a phosphine ligand and a chloro group. The packing diagrams confirmed that the intermolecular Cl⋯H interactions are not only the main cause of deviation from an ideal square planar geometry, but are also responsible for the Pd–S bond lengths variation. The DNA binding ability of the complexes was examined by cyclic voltammetry (CV). The cyclic voltammograms of the synthesized metallopharmaceuticals followed irreversible electrochemical behavior, which indicate the high reactivity of the reduced form of complexes. The results obtained from CV evidenced the catalytic role of DNA in enhancing the electron transfer processes of the complexes. The DNA binding studies are expected to provide useful insights about the unexplored mechanism by which anticancer drugs exert their biochemical action. [Copyright &y& Elsevier]

Abstract: Some copper(I) complexes of the type [Cu(L)(PPh3)2]X (1–4) [where L =2-chloro-(5-trifluoromethyl-phenyl)-pyridine-2-ylethylene-amine; X=Cl−, CN−, ClO4 − and BF4 −] have been prepared by the condensation of 3-amino-4-chloro-benzotrifluoride with 2-acetylpyridine followed by the reaction with [Cu(MeCN)2(PPh3)2]Cl, [Cu(MeCN)2(PPh3)2]CN, [Cu(MeCN)2(PPh3)2]ClO4 and [Cu(MeCN)2(PPh3)2]BF4. All the complexes 1–4 were characterized on the basis of elemental analysis, IR, UV–visible and 1H NMR spectral studies. The representative complex of the compound 3 has been characterized by single crystal X-ray diffraction which reveals that the central copper(I) ion assumes highly distorted tetrahedral geometry. All the complexes worked as effective catalyst for the amination of aryl halide. [Copyright &y& Elsevier]

Abstract: Six mixed ligand dithiocarbamate Pd(II) complexes (1–6) of general formula [(DT)Pd(PR3)Cl], where DT = dimethyldithiocarbamate (1, 5), diethyldithiocarbamate (2, 3), dicyclohexyldithiocarbamate (4), bis(2-methoxyethyl)dithiocarbamate (6); PR3 = benzyldiphenylphosphine (1), diphenyl-2-methoxyphenylphosphine (2), diphenyl-p-tolylphosphine (3), diphenyl-m-tolylphosphine (4), tricyclohexylphosphine (5), diphenyl-2-pyridylphosphine (6) have been synthesized and characterised using Elemental analysis, FT-IR, Raman and multinuclear magnetic resonance (NMR) spectroscopy. Compounds 1 and 2 were also characterized by single crystal X-ray diffraction technique (XRD). The XRD study reveals that the Pd(II) moiety has a pseudo square-planar geometry, in which two positions are occupied by the dithiocarbamate ligand in a bidentate fashion, while at the remaining two positions organophosphine and chloride are present. The anticancer activity of the synthesized metallodrugs was checked against DU145 human prostate carcinoma (HTB-81) cells, the IC50 values indicate that the compounds are highly active against these cells. These Pd(II) complexes also show moderate antibacterial activity against gram positive and gram negative bacteria. [Copyright &y& Elsevier]

Abstract: Three new nickel(II) complexes [Ni2(btec)(azopy)2(H2O)8]·2H2O (1), {[Ni(H2btec)(azopy)(H2O)2]·(azopy)} n (2) and {[Ni4(btec)2(azopy)3(H2O)10]·8H2O} n (3) (H4btec=1,2,4,5-benzenetetracarboxylic acid; azopy=4,4′-azobispyridine) have been synthesized by tuning the reaction temperature and the metal–ligand ratio. They were characterized by single-crystal X-ray diffraction and elemental analysis. 1 shows a binuclear structure, 2 exhibits a 2D grid, and 3 features an interesting 3D framework with (63)(4.62)(42.62.82) topology formed by two types of interlocked 2D layers. [Copyright &y& Elsevier]

Abstract: A novel 3D coordination framework [Pb2(hfipbb)2(bpp)]n (1) [H2hfipbb=4,4′-(hexa-fluoroisopropylidene)bis(benzoic acid), bpp=1,3-bis(4-pyridyl)propane] based on inorganic rod-shaped infinite Pb–O–Pb chain is presented, which possesses a new (4,5)-connected network topology and shows high thermal stability and strong photoluminescence at room temperature. [Copyright &y& Elsevier]

Abstract: Two new mononuclear mixed-ligand ruthenium(II) complexes with acetylacetonate ion (2,4-pentanedionate, acac) and functionalized bipyridine (bpy) in position 4, [Ru(bpyBr)2(acac)](PF6) (2; bpyBr = 4-Bromo-2,2′-bipyridine, acac=2,4-pentanedionate ion) and [Ru(bpyOH)2(acac)](PF6) (3; bpyOH=4-[2-methyl-3-butyn-2-ol]-2,2′-bipyridine) were prepared as candidates for building blocks. The 1H NMR, 13C NMR, UV–Vis, electrochemistry and FAB mass spectral data of these complexes are presented. [Copyright &y& Elsevier]

A novel three-dimensional cobalt-organic framework [(Me 2 NH 2 )Co 3 (μ 3 -OH)(tpt)(btb) 2 ]·guest ( 1 ) (tpt = 2.4.6-tri(4-pyridinyl)-1,3,5-triazine, H 3 btb = 4.4 ʹ ,4 ″ -benzene-1,3,5-triyl-tribenzoate) has been obtained by employing mixed tripodal ligands tpt and H 3 btb under solvothermal reaction condition. Topological analysis reveals that the whole framework structure of 1 possesses a two-fold interpenetrated 3,6-connected sit topology. Remarkably, the desolvated sample 1a shows a high CO 2 uptake of 89.5 cm 3 g − 1 (17.6 wt%) at 273 K and 1.0 bar, which is attributed to open metal sites and rich N donors of 1a . [ABSTRACT FROM AUTHOR]

Abstract: Light emission in red phosphorescent organic light-emitting diodes with mixed ligand dopant materials was studied. 1-phenylisoquinoline (piq) and phenylpyridine (ppy) moieties were introduced as ligands for Ir based phosphorescent dopants and light emission mechanism was investigated by changing the doping concentration of devices. Charge trapping dominated light emission in Ir(piq)3 but the charge trapping was not significant in mixed ligand dopant materials because of ppy ligand with less charge trapping character. High efficiency of 2.02lm/W could be obtained in the heteroleptic red dopants compared with 1.58lm/W in Ir(piq)3 and power efficiency improvement by ppy ligand was significant at low doping concentration. [Copyright &y& Elsevier]

Abstract: New mixed polypyridyl {NMIP=2′-(2″-nitro-3″,4″-methylenedioxyphenyl)imidazo-[4′,5′-f][1,10]-phenanthroline, dmb=4,4′-dimethyl-2,2′-bipyridine, bpy=2,2′-bipyridine} ruthenium(II) complexes [Ru(dmb)2(NMIP)]2+ (1) and [Ru(bpy)2(NMIP)]2+ (2) have been synthesized and characterized. The binding of these complexes to calf thymus DNA (CT-DNA) has been investigated with spectroscopic methods, viscosity and electrophoresis measurements. The experimental results indicate that both complexes could bind to DNA via partial intercalation from the minor/major groove. In addition, both complexes have been found to promote the single-stranded cleavage of plasmid pBR 322 DNA upon irradiation. Under comparable experimental conditions compared with [Ru(phen)2(NMIP)]2+, during the course of the dialysis at intervals of time, the CD signals of both complexes started from none, increased to the maximum magnitude, then no longer changed, and the activity of effective DNA cleavage dependence upon concentration degree lies in the following order: [Ru(phen)2NMIP]2+ >complex 2 >complex 1. [Copyright &y& Elsevier]

Abstract: Using mixed ligands and hydrothermal reactions, five new coordination polymers, [Co(o-CCA)(bpe)(H2O)] n ·0.25nCH3OH (1), [Ni(o-CCA)(bpe)(H2O)] n ·0.5nH2O (2), [M(p-CCA)(bpe)1.5(H2O)] n · nH2O (M=Co, (3); Ni, (4)) and [Co(o-BDC)(bpe)(H2O)] n · nH2O (5) (H2CCA=carboxycinnamic acid; bpe=1,2-bis(4-pyridyl)ethane; o-H2BDC=1,2-benzenedicarboxylic acid) were obtained. Complexes 1–4 possess complicated 3D metal-organic frameworks, but different position of functional dicarboxylate groups results in different architecture, forming diversity of structures. 1 and 2, 3 and 4 are isomorphous, respectively, in which solvent molecules are clatharated. When o-BDC instead of CCA was used, complex 5 was obtained, which is of (4,4) 2D grid-like layers with cavities. Thermal stabilities of complexes 1–4 were discussed. [Copyright &y& Elsevier]

Abstract: Two types of copper(II) and nickel(II) complexes derived from benzophenone anthranoylhydrazone (L1), 2-acetonaftanone anthranoylhydrazone (L2), 4-phenylacetonaftonone anthranoylhydrazone (L3), benzophenone salicyoylhydrazone (L4), 2-acetonaftanon salicyoylhydrazone (L5), 4-phenylacetonaftanon salicyoylhydrazone (L6) and bidentate heterocyclic base [1,10-phenanthroline (phen)] with general stoichiometry [ML2] and [ML(phen)]Cl have been synthesized and characterized by elemental analysis, infrared spectra, UV–vis electronic absorption spectra and magnetic susceptibility measurements. The effect of varying pH and solvent on the absorption behavior of both ligands and complexes have been investigated. According to the IR spectra, the ligands act as monobasic bidentate and coordination takes place in the enol tautomeric form. [Copyright &y& Elsevier]

Abstract: Three new copper complexes, [CuIICuI(ip)(ipH)(4,4′-bipy)3/2] n (1), [Cu(ip)(4,4′-bipy)] n ·3nH2O (2), and [Cu(ipH)2(4,4′-bipy)] n (3), have been hydrothermally synthesized by the reaction of Cu(NO3)2 ·3H2O with isophthalic acid (ipH2) and 4,4′-bipyridine (4,4′-bipy) under different reaction conditions. Complex 1, a mixed-valence copper(I,II) complex, exhibits a 2-D interpenetrating grid framework, in which five-coordinated CuII and three-coordinated CuI environments are established. The oxidation states of center Cu atoms have been confirmed by X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance spectra (EPR). Complex 2 features a 2-D box-like bilayer architecture, in which CuII atoms are linked by ip ligands to form a 1-D double-chain and the resulting chains are further strutted by the 4,4′-bipy ligands. In complex 3, two bridging 4,4′-bipy ligands and two terminal ipH ligands confine the CuII center in a square plane coordination geometry. The whole molecule of 3 was arranged into a 1-D linear chain structure. Additionally, the thermogravimetric analyses (TGA) for complexes 1–3 are also discussed in this paper. [Copyright &y& Elsevier]

Abstract: The copper complexes, oxalato(N,N,N′N′-tetramethylethylenediamine)copper(II) tetrahydrate (1), oxalato(N,N,N′-trimethyl-1,3-propanediamine)copper(II) (2), and oxalato(N,N,N′-trimethylethylenediamine)copper(II) (3), have been synthesized and structurally characterised. Compounds 1 and 2 share a common zig-zag polymeric structure in which the oxalates are bridging as well as chelating. The copper is in a distorted octahedral position in both compounds. Compound 3 is monomeric and the oxalate is chelating only. The copper is in a distorted square planar position. Diffuse reflectance spectroscopy and ESR spectroscopy showed a clear difference between the two types of structures. [Copyright &y& Elsevier]

A novel 3D nickel twofold-interpenetrating framework with mixed ligand, [Ni3(H2O)6(4,4′-bipy)4(SIPA)2] · 8H2O (1), has been hydrothermally prepared. X-ray diffraction shows the 3D framework contains Ni-4,4′-bipy 1D chain and 2D bilayer motifs and carboxylate spacers, and the connection of 1D chain and 2D bilayer motifs by carboxylate ligand results in the formation of the final framework with twofold-interpenetration net. [Copyright &y& Elsevier]

A novel metal-organic coordination polymer, [Ni2(dipic)2(4,4′-bpy)4(H2O)]·4H2O (H2dipic=pyridine-2,6-dicarboxylic acid), has been hydrothermally synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. Blue crystals crystallized in the monoclinic system, space group P21/c, a=10.582(2) A˚, b=20.246(4) A˚, c=7.2501(15) A˚, β=105.73(3)°, V=1495.0(5) A˚3, Z=2 and R=0.0377. The structure of the compound exhibits a novel three-dimensional supramolecular network, formed by hydrogen-bonding and π–π stacking interactions. Interestingly, the three-dimensional network consists of one-dimensional trapezoid channels, which accommodate lattice water molecules. [Copyright &y& Elsevier]

Synthesis of chromotropic copper(II) mixed ligand complexes of o-hydroxy benzoyl derivatives (L1) and dinitrogen bases (L2), general formula Cun(L1)(L2)nXn; where n=1 or 2, L1=4,6-diacetyl-resorcinol (H2DACR), o-hydroxy benzaldhyde (HOHBZ) or o-hydroxy acetophenone (HOHAP), L2=N,N,N′,N′-tetramethylethylenediamine (Me4en), 1,10-phenanthroline (phen) or bipyridine (bipy) and X=ClO4−, NO3− or Br− have been reported. Spectral, magnetic and molar conductance measurements as well as analytical data of these complexes show either mononuclear structure for OHBZ and OHAP or binuclear structure for DACR complexes. The IR stretching vibration frequencies of Cu&z.sbnd;N and Cu&z.sbnd;O are linearly correlated with the d–d absorption frequencies. The d–d absorption bands of Me4en-complexes in weak donor solvents suggest square-planar, distorted octahedral and distorted trigonal bipyramid geometries for the perchlorate, nitrate and bromide complexes, respectively. However, an octahedral structure is identified for the complexes in strong donor solvents. Perchlorate complexes show a remarkable color change from violet to green as the donor ability of the axial ligand increases, whereas bromide complexes are mainly affected by the Lewis acidity of the axial ligand. Specific and non-specific interactions of solvent molecules with the complexes are investigated using the unified solvation model. Calculations of the electronic transition probability (f) of the d–d band along with molecular orbital calculations of ligands have been carried out and correlated with the experimental data. [Copyright &y& Elsevier]

Solvatochromic mixed ligand complexes of copper(II) with malonate and diamine derivatives, Cun(RMal)(diam)nXm (where n=1 or 2, m=1–4, RMal, malonic acid (H2Mal), diethylmalonate (HDEtMal) or diethylethoxyethylenemalonate (DEtEMal), and diam, ethylenediamine (en), 1,3-propylenediamine (1,3-pn), N,N,N′-trimethylethylenediamine (Me3en), N,N,N′-triethylethylenediamine (Et3en), N,N,N′,N′-tetramethylethylenediamine (Me4en), N,N,N′,N′-tetramethylpropylenediamine (Me4pn), or N-methyl-1,4-diazacycloheptane (medach); and X=ClO4− or Cl−), has been synthesized and characterized by spectroscopic, magnetic, molar conductance and electrochemical measurements. The mass spectra along with the analytical data of the complexes show peaks with m/e corresponding to a bridged binuclear structure for the chloride complexes, while perchlorate complexes showed either mononuclear structure for DEtMal and DEtEMal or bridged binuclear structure for Mal complexes. These results correspond to IR spectral data, which indicated that the modes of ester and carboxylato coordination sites are mono- and/or bidentate. The d–d absorption bands in weak donor solvents suggest square-planar and distorted square pyramidal-trigonal bipyramid geometries for the perchlorate and chloride complexes; respectively. On the other hand, an octahedral structure is identified for complexes in strong donor solvents. Perchlorate complexes show a drastic color change from violet to green as the donation ability of solvent increases, whereas chloride complexes are highly affected by the acceptor properties of the solvent. Cyclic voltammetric measurements on the complexes, proposed a quasi-reversible or irreversible and mainly diffusion controlled reduction process. Such behavior has been explained according to the ECE mechanism. A linear correlation has been found between the Cu(II) reduction potential and the spectral data. Molecular orbital calculations were performed for the ligands on the bases of PM3 level and the results corresponded to the experimental data. The data are discussed in terms of chromotropic concept and its applications as a Lewis acid–base color indicator. [Copyright &y& Elsevier]

• Rapid synthesis of mixed ligand MOF by ultrasonication method. • The highest H 2 S adsorption capacity of 128.4 mg g−1. • XPS analysis confirmed sulfides and sulfates after H 2 S adsorption. • Partial regeneration of spent MOF by the successive effect of methanol and UV irradiation. A mixed ligand Cu-based MOF, Cu(BDC) 0.5 (BDC-NH 2) 0.5 was synthesized by a rapid ultrasonication method for the adsorptive removal of hydrogen sulfide (H 2 S) gas at room temperature. The MOF has a sheet-like morphology with 100 nm thickness crystallized in the monoclinic symmetry (a = 11.27 Å, b = 14.82 Å, c = 7.95 Å, β = 110.8°) with C2/m space group. The surface area and pore volume was 19.4 m2 g−1 and 0.024 cm3 g−1, respectively. The XPS analysis confirmed a near equal proportion of Cu(I) and Cu(II)-sites in the MOF. The MOF showed the H 2 S adsorption capacity of 128.4 mg g−1 for 500 ppm of H 2 S flowing at a rate of 100 mL min−1, which is among the highest values reported for Cu-based MOFs. The spent MOF was regenerated by a methanol and UV-irradiation method, which significantly improved the adsorption capacity. The H 2 S adsorbed onto the MOF by breaking Cu-carboxylate bonds with the formation of covellite CuS nanoparticles and sulfates. The spectroscopic analysis predicted a Cu(OH)-type sites after UV-irradiation along with increased surface area, which were responsible for an enhanced adsorption capacity of the regenerated sample. [ABSTRACT FROM AUTHOR]

A highly water stable zinc metal–organic framework (ZnMOF), {[Zn(HL) 2 } n , was synthesized using a triazole–carboxylate-based mixed ligand (L = 5-(4H-1,2,4-triazol-4-yl)isophthalic acid). A 2D MOF was formed by hydrothermal synthesis, and extended to a 3D supramolecular network through strong hydrogen bonding. This MOF was fully characterized by Fourier-transformation infrared spectroscopy, thermogravimetric analysis, single-crystal X-ray diffraction (XRD), powder XRD and elemental analysis. Owing to the d10 configuration of this ZnMOF, its luminescent properties were suitable for the sensing of the CN− ions over other anions, as inferred from the florescence result. However, regarding the catalytic mechanism, this ZnMOF showed a strong ability to react with CN−, which might be due to the hydrogen bonding between the COOH groups without coordination. This interaction behavior with CN− ions makes the ZnMOF a promising heterogeneous catalyst for Knoevenagel condensations using malononitrile and aldehyde derivatives as reactants under mild conditions. All reactions were conducted in water as a green solvent. Unlabelled Image • Design of bifunctional zinc MOF, bearing triazole-carboxylate mixed ligand. • Heterogeneous catalyst for C C bond forming reactions such as Knoevenagel condensation. • Highly efficient catalyst works under mild conditions in water at room temperature. • Selective sensing of CN− ions over other anions by ZnMOF , using florescence technique. • Detection of CN− ions supports the proposed mechanism of Knoevenagel condensation. [ABSTRACT FROM AUTHOR]

A new dinuclear paddlewheel Cu(II)-metallamacrocycle with the formula [{Cu 2 (3-bpoba)(adman) 4 }·3DMF] 2 (1) (where, 3-bpoba is 4,4′-oxybis(N -(pyridin-3-yl)benzamide); adman is 1-adamantanecarboxylic acid), has been synthesized using the solvothermal protocol. A single-crystal X-ray analysis reveals that 1 exhibit a dinuclear paddlewheel metallamacrocycle architecture, where the co-ligand adman is playing a crucial role in the formation of metallacyclic structure. TGA analysis suggests that 1 is stable up to 250 °C. Density Functional Theory (DFT) has been employed to calculate the equilibrium geometry of the complex as isolated species in the gaseous phase. The structural analysis was complemented by additional spectroscopic studies and Hirshfeld surface analysis. Variable temperature magnetic susceptibility measurements on 1 show a strongly coupled magnetic dimer (J = −538(2) K) as expected for a classic Cu-paddlewheel structure. Image 1 • Dinuclear paddlewheel Metallamacrocycle. • Co-ligand responsible for dimeric structure. • Strongly coupled antiferromagnetic dimer. • Mixed ligand approach. [ABSTRACT FROM AUTHOR]

Two different frameworks had been constructed under the similar reaction conditions except for the distinct metal salts. The structures of the complexes vary from 3-fold interpenetrated pcu topology to acs topology. The coordination habits of metal ions is responsible for the difference of final structures. Weak antiferromagnetic interactions exist within the binuclear metal ions. • Two different MOFs had been constructed under similar reaction conditions. • The structures of the complexes vary from 3-fold interpenetrated pcu to acs topology. • The coordination habit of metal ions is responsible for the structure difference. • Weak antiferromagnetic interactions exist within the binuclear units. Two 6-connected (6-c) edge-transitive nets, namely, [Co 2 (2,6-ndc) 2 (4-bpdb)·2CH 3 OH·2H 2 O] n , (1), and [Ni 2 (2,6-ndc) 2 (4-bpdb)·(H 2 O) 3 ·2DMF] n (2) (2,6-H 2 ndc = 2,6-naphthalenedicarboxylic acid, 4-bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene), were synthesized under solvothermal conditions. The structure of 1 manifests a three-fold interpenetrated 3D pcu topology based on paddle-wheel [Co 2 (μ 2 -η1:η1-COO) 4 ] dimers. The structure of 2 possesses a three-fold interpenetrated 3D acs topology based on [Ni 2 (μ 2 -OH 2)(μ 2 -η1:η1-COO) 2 (η1-COO) 2 ] dimeric units. Magnetic analyses indicate that both two compounds show weak antiferromagnetic interactions within binuclear CoII 2 and NiII 2 units. [ABSTRACT FROM AUTHOR]

A phosphatooxalate compound {Na2[Zn(C2O4)1.5H2PO4] · 2H2O}n 1 was synthesized under hydrothermal condition and characterized by single-crystal X-ray diffraction, IR spectroscopy, thermal gravimetric analysis (TGA) and fluorescent spectroscopy. X-ray single-crystal analysis revealed that its structure was a new mixed inorganic–organic ligand supramolecular framework building up through multilayer assembly. [Copyright &y& Elsevier]