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In this work, two MOFs, {[Cd3(L)2(m-BDC)(NO3)4]��2(H2O)}n (1) and [Zn3(L)(m-BDC)3]n (2), were synthesized using the hydrothermal method. Single crystal diffraction showed that the flexible tripod ligand L (1,3,5-[1-(2-methylimidazole-methylene)]benzene) delivers completely different configurations under the influence of the coordination metal [Cd(II), Zn(II)] ions, resulting in two completely different structures. In 1, the flexible tripod ligand L adopted a "chair" conformation which combined with Cd(II) ions, forming a two-dimensional structure in the orthorhombic C2221 space group. In 2, L adopted a "bowl" conformation which combined with Zn(II) ions, forming another two-dimensional structure in the P-3m1 space group. The synthesized MOFs were characterized by PXRD, thermogravimetry (TGA), infrared spectroscopy (IR), elemental analysis, fluorescence property analysis, Hirshfeld surface analysis, and density functional theory (DFT) quantitative calculations. The fluorescence analysis displayed that the maximum emission wavelength of 1 and 2 has a blue shift. In addition, the results of thermogravimetric analysis (TGA) showed that the thermal stability of 1 is 150 ��C higher than that of 2. This is probably because the energy of "chair" conformation is lower than that of the "bowl" conformation, which makes 1 more stable than that of 2.

Ligand-free, copper-free Sonogashira coupling reaction and styrene hydrogenation catalysis by linear organic dodecanethiol stabilized palladium nanoparticles (PdTNPs) were studied. At 70 °C and in ...

Refluxing HL [5-chloro-2-((2-hydroxynaphthalen-1-yl)diazenyl)phenyl)(phenyl)methanone] with [(2-ppy)2Ir(μ-Cl)]2 in ethanol-dichloromethane mixture in the presence of a base (NEt3) afforded complex of composition [Ir(2-ppy)2(L)], where the azo-ligand is coordinated to iridium(III) center as monoanionic bidentate N,O-donors. The ligand and complex were characterized unequivocally. Molecular structures of both the ligand and complex were confirmed by single-crystal X-ray diffraction. The ground and excited-state geometries, absorption, and emission properties of the iridium(III) complex were further examined by DFT and TD-DFT methods. The complex exhibits a blue-violet emission band at 395 nm with quantum yield (Φ) 0.06. Experimental and theoretical studies support the fact that the nature of emission is an admixture of 3IL and 3MLCT state.

Herein, we report a bulky variant of a bis-benzimidazole carboxylate ligand. The five-position of the benzimidazole groups were substituted with tertiary butyl groups with the intention of preventing bis-ligation and oligomerization, as was observed in other studies using similar ligands. Unfortunately, even with the bulkier substituents, the new ligand still formed a bis-ligated structure. Although the new ligand did not afford the desired mono-ligated species under the conditions studied here, the preparation of the new ligand and coordination compounds provides an added design principle in the ongoing efforts of preparing structurally faithful 2-histidine-1-carboxylate model ligands in biomimetic chemistry.

Two monomeric complexes, [NiL2·3H2O] (1) and [Nd2L3(NO3)3] (2), with a tridentate ONO-donor Schiff base ligand HL (HL = 2-hydroxybenzaldehyde-4-aminoantipyrine) have been synthesized. Single-crystal X-ray diffraction analysis indicates that the asymmetric unit of 1 contains one Ni(II) and two L− ligands, while 2 consists of two Nd(III) ions, three L− ligands, and three NO3− ions. Complexes 1 and 2 are both 0-D discrete monomers, and there are intermolecular π–π interactions in 1 and intramolecular π–π interactions in 2. The discrete [NiL2·3H2O] monomers are further connected through π–π interactions, resulting in a 3-D supramolecular structure. Powder XRD and TG-DSC were performed for 1 and 2. Antimicrobial experiments show that 1 displays significant antibacterial effect against Bacillary dysentery and Escherichia coli in comparison with that of Schiff base ligand.

By applying a mixed-ligand approach based on an amino functionalized ligand 1-aminobenzene-3,4,5-tricarboxylic acid (H3abta), a novel metal-organic framework (MOF) containing Co(II) ion {[Co2.5(abt...

Mixed-ligand complexes of bivalent metal ions, viz, Co(II), Ni(II), Cu(II), and Zn(II) of the composition [ML(dan)]Cl (where L = Schiff base ligand, dan = 1,8-diaminonaphthalene and M = Co(II), Ni(II), Cu(II), Zn(II)) have been synthesized and characterized. The stoichiometric ratio of the prepared complexes has been estimated using complementary techniques such as elemental analyses, FT-IR, UV-vis and EPR spectra, magnetic and molar conductivity measurements. The study shows that all the complexes have square planar geometry. The synthesized compounds have been tested in vitro against various types of pathogenic bacteria to weigh up their antimicrobial properties. They have lofty activity against the tested bacteria. The complexes have higher activity than the free ligands. The interaction of synthesized complexes with calf thymus DNA (CT-DNA) has been studied by absorption spectroscopic technique and viscosity measurements. The complexes show a successful interaction with CT-DNA via intercalation mode. In addition, molecular docking approach has been performed for predicting the binding free energy of the synthesized compounds with 1BNA receptor.

Eight cyclopentadienyl U(III) iodide complexes have been synthesized from UI3 and crystallographically characterized to show the variations that can occur with this ligand set and uranium in the +3 oxidation state: (C5Me5)2UI(THF), {[K(OEt2)2][(C5Me5)2U(µ–I)2]}2, [K(18-crown-6)][(C5Me5)2U(µ–I)2], [K(2.2.2-cryptand)][(C5Me5)2UI2], [Li(THF)4][(C5Me5)2UI2], [Li(THF)3][(C5Me5)2UI(µ–I)], {[K(18-crown-6)]2(µ–toluene)}{[C5H3(SiMe3)2]2UI(µ–I)}2 and [(C5Me5)U]3(µ3–I)2 (µ–I)3I(THF)2. The structures show that small modifications in synthetic and crystallization procedures lead to changes in the coordination mode of the isolated product such that many structural options are available that can only be defined by X-ray crystallography. These variations highlight the many low energy options available in the reaction chemistry of this combination of metal and ligands.

A new N3-tridentate imine ligand, 2,6-diacetylpyridinediphenylhydrazone (DAPH) (L), and its Pd(II), V(IV)O, and Ag(I) complexes were synthesized and characterized via elemental analysis, FT-IR, NMR...

The solid-state chemistry of coordination complexes has become an actively developing research area of modern inorganic chemistry. Herein, Zn and Hg coordination compounds containing a N,N′-bidentate chelating Schiff-base ligand were synthesized and then characterized using spectroscopic techniques and single-crystal X-ray crystallography. The molecular structures and crystal packing modes of these complexes, as well as the crystal structures of related compounds, were investigated thoroughly using geometrical and Hirshfeld surface analyses, as well as theoretical calculations. It has been revealed that the supramolecular architecture of these series of coordination complexes is governed mainly by a combination of chelate···π and π···π stacking, and non-classical hydrogen bonding interactions. This study provides further insight into the understanding of the coordination chemistry of group IIB complexes containing Schiff-base ligand and the role of weak non-covalent interactions in the solid-state structure of coordination compounds.

Depending on the in situ ligand transformation of 3,5-di(1,2,4-triazol-1-yl)benzonitrile (DTCN) to 3,5-di(1,2,4-triazol-1-yl)benzoic acid (DTCA) under hydrothermal condition, three polyoxometalate-based copper complexes, [CuI 4CuII 2(OH)2(H2O)4(DTCA)4(HPMoVI 10MoV 2O39)] (1), [Cu4(OH)2(H2O)4(DTCA)2(SiW12O40)]·11H2O (2), and {Cu2Cl(H2O)(HDTCA)2[CrMo6(OH)6O18)]}·4H2O (3), have been isolated through changing the polyoxoanions. Introducing Keggin-type polyoxoanions [PMo12O40]3− or [SiW12O40]4− to reaction systems, both 1 and 2 display 3-D framework structures containing Cu/DTCA metal-organic belts, and a kind of poly-Keggin chain derived from [PMo12O40]3− polyoxoanions exist in 1. When the Anderson-type polyoxoanion [CrMo6(OH)6O18)]3− is utilized, a 2-D grid-like layer resulted in 3, in which the DTCA ligands are embedded, revealing that the polyoxoanions have key roles in regulating the structures of complexes. The investigations on electrochemical properties and photocatalytic activities for the degradation of organic dyes of 1–3 have been carried out.

Three new polyoxometalate (POM)-based metal–organic complexes, {Ni3(Hpytty)2[AlMo6(OH)5O19](H2O)4(CH3O)}·5H2O (1), {Ni3(Hpytty)2 [CrMo6(OH)5O19](H2O)10}·6H2O (2), and {Co2(pytty)[γ-Mo8O26]0.5 (H2O)...

We report the synthesis and characterization of a two-dimensional Zn(II) coordination polymer employing a ligand with a biphenyl core containing imidazole and carboxylate groups in the presence of acetate moieties as bridging molecules. The obtained [ZnLAc]n was structurally characterized via X-ray, FTIR, TGA, PXRD, SEM and EDX analyses. Computer-aided calculations based on density functional theory (DFT) were employed to assess the optimal conformational geometries of both the starting ligand and the Zn(II) complex. Computational results were compared with the experimental data, disclosing a reasonable agreement. Comparisons between the single-crystal structures and the calculated optimized geometries of the molecular entities are discussed. In addition, the time-dependent DFT method (TD-DFT) was applied to assess the first excited state of the ligand and complex.

In this work, 5,5′-carbonyldiisophthalic acid (H4cipa) was used as a ligand to react with Zn(NO3)2·6H2O in a mixed solvent of DMF and water to prepare a new metal-organic framework (MOF) with the chemical formula of [Zn2(cipa)(H2O)2](DMF) (1). Due to its O donor sites within the one-dimensional channels and high density of open metal sites, the activated 1a was applied as a heterogeneous catalyst for the formation of C–C bonds of carbonyl compounds in the absence of solvents, which shows high efficiency and size-selectivity. Furthermore, the possible reaction mechanism has been proposed based on the experimental results. The treatment activity of the new compound on the Mg63 osteosarcoma cell line was evaluated and the possible mechanism was discussed. First, flow cytometry was performed to detect the levels of the Mg63 cancer cells’ autophagy levels after indicated compound treatment. Next, real time RT-PCR assay was further conducted to measure the relative expression levels of the autophagic genes under treatment.

A new asymmetric salamo-based ligand (H2L) was synthesized and upon reaction with Cu(ClO4)2 an extremely rare dinuclear Cu(II) complex [Cu2(L)2] was formed and characterized by elemental analyses, ...

Two metallacyclophanes have been assembled by self-assembly processes involving the trianionic compartmental ligand (L3-), nickel(II) and sodium or potassium ions: [LNiNa]2·C2H5OH·2H2O (1) and [LNiK]2·C2H5OH·2H2O (2) (the Schiff-base proligand, H3L, is obtained by condensation of o-vanillin and DL-2,3-diaminopropionic acid). The structures of 1 and 2 can be viewed as resulting from two enantiomeric fragments, {LNiNa/K} connected to each other by the two carboxylato groups. The intramolecular distance between the phenyl rings is 3.64 Å. The sodium/potassium ions are coordinated by five oxygens in a planar pentagon. Weak intermolecular sodium/potassium···CH interactions are observed in the packing diagrams of the two compounds. The intra- and intermolecular non-covalent interactions are analyzed through several methods based on electron density, Bader’s QTAIM, non-covalent interactions index and natural bond orbitals. They confirm the in-plane five coordination of the alkali ion, which is of an electrostatic, non-covalent nature and the intermolecular interaction with σ C-H orbitals as well. The diffuse reflectance spectra of the two compounds show characteristic features of square-planar nickel(II) chromophores.

Herein, an octanuclear complex [Mn8(μ4-O)4(phpy)8(MeOH)4]·MeOH·H2O based on 5-(2-hydroxyphenyl)-3-pyrazole (HphpyH) has been successfully synthesized and characterized. The compound can self-assemb...

Nine new complexes [(η6-C6H5-CH3)RuLCl]+(PF6)ˉ (where L = N,N′-bidentate ligand; (C5H4NCH = N-Ar) where Ar = 4-methylphenyl (C20H20ClF6N2PRu, 1); 3,4-dimethylphenyl (C21H22ClF6N2PRu, 2); 2,4,6-trimethylphenyl (C21H24ClF6N2PRu, 3); 4-bromophenyl (C19H17ClBrF6N2PRu, 4); 2,5-dimethylphenyl (C21H22ClF6N2PRu, 5); 2-flourophenyl (C19H17ClF7N2PRu, 6), (4-methoxyphenyl)methylene (C21H22ClF6N2OPRu, 7); phenylmethylene (C20H20ClF6N2PRu, 8); and 3,5-dimethylphenyl (C21H22ClF6N2PRu, 9) were synthesized by reacting the corresponding N,N′-bidentate ligands with the ruthenium arene dimer in a 2:1 ratio. The compounds were fully characterized via 1H NMR and 13C NMR, IR, and UV-vis spectroscopy and elemental analyses. The molecular structures of representative complexes (1, 7, and 8) were established by single-crystal X-ray diffraction studies. In the molecular structures of the complexes, the ligands coordinate to the Ru(II) centers via the pyridine nitrogen atom and the imine N atom in a bidentate manner. The other coordination sites of the Ru(II) center are occupied by the tolyl system in an η6 manner resulting in geometry often referred to as “pseudo-octahedral piano-stool.” All compounds were evaluated for their in vitro antibacterial activity by the disk diffusion method against a panel of Gram-negative and Gram-positive bacteria. The complexes showed promising bactericidal activity against methicillin-resistant Staphylococcus aureus ATCC 43300.

A thiazole-based chalconoid ligand (E)-3-(2-hydroxyphenyl)-1-(thiazol-2-yl)prop-2-en-1-one (HPTP) and its Co(II), Ni(II), Cu(II) and Zn(II) complexes have been synthesized. The synthesized compounds were characterized by elemental analysis, molar conductance, UV-vis., FT-IR, NMR, mass spectral techniques, magnetic susceptibility, powder XRD and SEM with EDAX. In addition, the structures were optimized with Density Functional Theory (DFT) computations. The Lewis base nature of HPTP, stability on coordination, charge transfer interactions, quantum chemical parameters and vibrational frequencies were analyzed. The molecules were docked with 5FX6 receptor as possible inhibitors of human rhinovirus (HRV) 3 C protease.

New mononuclear Cu(II), Co(II) and Ni(II) complexes of novel azo-dye ligand 4-[(4-hydroxy-7-methyl-1,3-benzothiazol-2-yl)diazenyl]-5-methyl-2-phenyl-2,4-dihydro-3-pyrazol-3-one (L) with O,N-donor s...

A new metal–organic framework (MOF) formulated as {[Co(L)]·4H2O·2CH3CN}n (1) has been prepared by solvothermal reaction of Co(NO3)2·6H2O with a bifunctional ligand 5-(3,5-di-pyridin-4-yl-[1, 2, 4]t...

The coordination behavior of the tridentate alkoxy ligand 6,6'-(((2-hydroxyethyl)azanediyl)bis(methylene)) bis(2,4-di-tert-butylphenol) (termed H3-AM-DBP2) with group 4 metal alkoxides ([M(OR)4]) in a 1:1 ratio was previously found to generate [(ONep)Ti(κ 4 (O,O’,O”,N)-AM-DBP2)] and [(OR)Zr(κ 4 (μ-O,O’,O”,N)-AM-DBP2)]2 (M = Zr, Hf). Additional studies revealed that increasing the stoichiometric ratio to 1:2 H3-AM-DBP2:[M(OR)4] led to the isolation of [(ONep)Ti(κ 4 (μ-O,O’,O”,N)-AM-DBP2)(μ-ONep)Ti(ONep)3] (1)•tol, [(OBu t)Zr(κ 4 (μ-O,O’,O”,N)-AM-DBP2)(μ-OBu t)Zr(OBu t)3] (2) and [(OBu t)Hf(κ 4 (μ-O,O’,O”,N)-AM-DBP2)(μ-OBu t)Hf(OBu t)3] (3). The asymmetric dinuclear complexes of 1-3 resemble the chelation of a [M(OR)4] moiety to a “(OR)M(κ 4 (O,O’,O”,N)-AM-DBP2)” fragment. The metal complexed by the AM-DBP2 ligand has a pseudo octahedral geometry while the other metal adopts an intermediate trigonal bipyramidal (TBP-5)/square base pyramidal (SBP-5) geometry for 1 but a distorted SBP-5 for both 2 and 3. The structure and properties of 1-3 were analyzed by computational modeling and fully characterized by standard analytical methods.

A new Co(II)-containing coordination polymer formulated as [Co(H-ntb)]n (1) has been synthesized via reaction of Co(NO3)2·6H2O with the 4,4′,4′’-nitrilotribenzoate (H3ntb) ligand under solvothermal...

Three mononuclear Nd(III) complexes [Nd(HL1)2(NO3)3] (1, HL1=2-methoxy-6-[(E)-(phenylimino)methyl]phenol), [Nd(HL2)3(NO3)3] (2, HL2=5-methoxy-2-[(E)-(phenylimino)methyl]phenol) and [Nd(HL3)2(NO3)3]...

Ru(II)-polypyridine complexes of the general formula [Ru(L1/L2)(phen)2]X2 (1a–6a) and [Ru(L1/L2)(bipy)2]X2 (1b–6b) (where X = ClO4, BF4, PF6; phen = 1,10-phenanthroline, bipy = 2,2′-bipyridine) wer...

A new Cu(II) complex with flavonoxylacetate ligand was synthesized and characterized. The structure of the complex was determined by X-ray single crystal diffraction technique. In the crystal struc...

By introducing alkaline-earth metal ions (Mg2+, Ca2+, and Sr2+) as structure-directing agents, three new heterometallic complexes, Mg(H2O)6·[Cu2Mg(L)4(H2O)4]·4H2O (1), [CuCa(L)2(H2O)4]n (2) and [CuSr(L)2(H2O)4]n (3) [H2L = 4-(3-(pyridine-4-yl)-1H-1,2,4-triazol-5-yl)picolinic acid], have been synthesized under hydrothermal conditions and structurally characterized. H2L was in situ generated from hydrolysis of the well-known selective xanthine oxidase inhibitor topiroxostat. Complex 1 crystallizes in the space group P21/c and exhibits a zero-dimensional (0-D) structure containing the discrete [Mg(H2O)6]2+ cationic and [Cu2Mg(L)4(H2O)4]2– dianionic moieties. Complexes 2 and 3 are isostructural and crystallize in the space group C2/c, with one-dimensional (1-D) polymeric structure with infinite Cu(II)–Ca/Sr–carboxylate chains. The results reveal the significant influence of the alkaline-earth metal ions on the molecular structure. Their spectroscopic, thermal and solid-state luminescent properties have also been investigated.

N’-(2-Hydroxy-4-methoxybenzylidene)isonicotinohydrazide (H2L) was used as ligand to prepare new oxidovanadium(V) complex [VOL(OMe)(MeOH)] (1) and new dioxidomolybdenum(VI) complex [MoO2L(Me...

Binuclear Ni(II) chelating complex with chiral Schiff base 1-((E)-(((1S,2R)-2-hydroxy-2,3-dihydro-1H-inden-1-yl)imino)methyl)naphthalene-2-ol [Ni2L2] has been synthesized. The structure of [Ni2L2] ...

A new dinuclear copper(II) Schiff base complex, [Cu2L2(H2O)2(µ-ClO4)]ClO4, was synthesized and characterized by single crystal X-ray crystallography, FT-IR and UV-Vis spectroscopy, and elemental an...

Solvothermal reaction of a multidentate ligand (tetrakis[4-(1-triazolyl)phenyl]-methane (ttpm)), with Cd(NO3)2 afforded a cationic Cd(II) coordination polymer {[Cd(ttpm)·DMSO]·2NO3}n. Singl...

A series of mixed-ligand Cu(II) complexes of the type: (i) [Cu(l-pro)(diimine)(H2O)n](ClO4) (n = 0 or 1), where l-pro is l-proline and diimine is 2,2′-bipyridine (bpy; 1), (ii) 4,4′-dimethy...

The coordination chemistry of (diphenyl((5-phenyl-1H-pyrazol-3-yl)methyl) phosphine oxide), 1, was explored. Reacting appropriate equivalents of this ligand and either cobalt perchlorate or MoO2Cl2 results in formation of [Co((C6H5)2POCH2(C3N2H2)(C6H5))2(C4H8O)2][ClO4]2, 2, and MoO2Cl2((C6H5)2POCH2(C3N2H2)(C6H5))(THF), 3. Complexes were characterized by FTIR, NMR, TGA and elemental analyses. Single crystal X-ray spectroscopy reveals octahedral geometries for both compounds. Complex 2 consists of two trans THF ligands in axial positions and two (diphenyl((5-phenyl-1H-pyrazol-3-yl)methyl) phosphine oxide) ligands occupying equatorial positions resulting in an overall octahedral geometry. Two perchlorate counter anions complete the structure. The Co ion resides on an inversion point. THF contains disorder with the four carbon atoms and the major orientation refined to an occupancy of 86.1(9)%. Complex 3 consists of the cis-dioxo MoO2 unit bonded with axial trans-chloride ligands and 1 in the equatorial plane completing the disordered octahedral geometry. A THF ligand is hydrogen bonded to the H-atom on the nitrogen of the pyrazole moiety in ligand 1. DFT calculations based on geometries obtained crystallographically were useful in assigning FTIR peaks and the UV-vis spectra.

Three new Cu(II) Schiff base complexes with bidentate N-donor heterocyclic co-ligands, 2,2'-bipyridine (1), 1,10-phenanthroline (2), and 2,9-dimethyl-1,10-phenanthroline (3), were synthesiz...

A new tridentate Schiff base ligand, 2-((2-(dimethylamino)ethylimino)methyl)-6-ethoxyphenol (HL1), has been prepared by a one-pot condensation reactions, which was further used in the const...

Three NO+-ruthenium(II) complexes were prepared by using cis-[RuCl2(DMSO)4] as precursor, P, and the compounds benzohydroxamic acid (BHA), 1′, anti-diphenylglyoxime (H2dpg), 2′, and dimethy...

In the present investigation, the bioactive azo-dye ligand 1,5-dimethyl-4-[(3-methyl-5-oxo-1-phenyl-4,5-dihydro-1H-pyrazol-4-yl)diazenyl]-2-phenyl-1,2-dihydro-3H-pyrazol-3-one (L) and its transition metal complexes have been synthesized and characterized by various physical and spectroscopic techniques to elucidate their geometrical structures. The molar conductivity measurements confirmed the non-electrolytic nature of the complexes. EPR spectroscopy indicated that the metal complexes are monomeric in nature and exhibited octahedral geometry. The redox behavior of the copper complex was studied by the cyclic voltammetric technique in DMF solution and the complex showed well-established redox behavior at a scan rate of 0.05 V s−1. The antimicrobial activity of the ligand and its metal complexes were screened against Escherichia coli, Bacillus subtilis, Aspergillus niger, and Candida albicans, and the results indicated increased activity after coordination of the ligand to the metal ions. The metal complexes exhibited enhanced antitubercular activity after chelation against M. tuberculosis. The DNA-binding experiments showed that the ligand and its metal complexes showed effective binding properties through intercalative mode against CT-DNA. All the synthesized molecules showed partial cleavage of supercoiled plasmid pUC18 DNA.

Reaction of copper(II) chloride or bromide with 2-chloro-3-bromopyridine or 2,3-dichloropyridine generates a family of compounds of the general formula L2CuX2 (1–4). X-ray crystallography shows tha...

Two metal–organic frameworks based on a multifunctional ligand 2-(5-bromo-pyridin-3-yl)-1H-imidazole-4,5-dicarboxylic acid (H3L), [Mn(HL)(C2H5OH)]n (1) and {[Zn(HL)(H2O)2]·H2O}n (2), have been hydro/solvothermally synthesized and characterized by IR, elemental analyses, X-ray powder and single-crystal diffractions, and thermogravimetric analyses. In 1, (HL)2– ligands adopt the μ 3-kN,O:kN′,O′:kN′′ coordination mode and use their imidazoledicarboxylates to bis-chelate MnII into left- and right-handed helixes which are further bridged into a mesolayer structure with (4·82) topology through the coordination of their pyridyl groups. In 2, (HL)2– ligands only use their imidazoledicarboxylates to bis-chelate ZnII into linear chains which are further linked into a 2D supramolecular framework through interchain hydrogen–bonding interactions. Interestingly, the structures of 1 and 2 are mainly dominated by the bis-N,O-chelation of the imidazoledicarboxylate in (HL)2–. As for the formation of the imidazoledicarboxylate-bridged helical chains in 1 or straight chains in 2, it largely depends on the cis- or trans-chelation of two imidazoledicarboxylates around the same metal center. Magnetostructural analysis of 1 discloses that the bis-N,O-chelating imidazoledicarboxylate of (HL)2– transmits antiferromagnetic interactions along the imidazoledicarboxylate-bridged helical chain with the spin-coupling constant of –0.71 cm–1. Additionally, 2 emits greatly enhanced blue fluorescence mainly originating from the intraligand charge transition.

Two coordination polymers of lead(II), 1D-{Pb(DFPT)(μ-Br)2}n (1) and 1D-helical-{Pb(DFPT)(μ-I)2}n (2), with 5,6-di(furan-2-yl)-3-(pyridin-2-yl)-1,2,4-triazine (DFPT) were prepared and identified by elemental analysis, FT-IR, 1H NMR spectroscopy and single-crystal X-ray diffraction. In the 1D-double chain-coordination polymers of 1 and 2, the lead atom has a PbNpyNtz(μ-X)4 (X: Br (1), I (2)) environment with distorted octahedral geometry and hemidirected coordination sphere. The type of the polymeric chain in both complexes is different; 1 has a linear expansion while 2 shows a helix structure with a racemic mixture of the P and M chains. In the crystal network of the complexes, in addition to hydrogen bonds, there are triazine···furyl and furyl···furyl ring π–π stacking interactions. The thermodynamic stability of the compounds, the polymer stability slope for pentameric chains (PSS5) and also the energy variation of the free DFPT ligand for 360° rotation of the pyridine ring were studied by DFT calculations.

Hydrolysis of the vinylidene complex [Ru(η5-C5H5){=C=C(H)Ph} (PPh3){P(OMe)3}]BPh4 afforded the mixed-ligands carbonyl derivative [Ru(η5-C5H5)(CO)(PPh3){P(OMe)3}]BPh4. Its structure has been determined by X-ray diffraction. The compound crystallizes in the monoclinic crystal system, space group P21/c, with one anion and one cation in the asymmetric unit. The cation complex contains a ruthenium atom in a half-sandwich piano-stool structure. One trimethylphosphito, one triphenylphosphine and one carbonyl ligand are the legs of the stool.

Eight new mixed ligand complexes of dioxomolybdenum(VI) with 2-hydroxy-3-methoxy/3,5-dibromo benzaldehyde 4-phenyl/ethyl-S-methyl/butyl thiosemicarbazones (L) were synthesized. The complexes of general formula [MoO2LD] (D: methanol, pyridine) were characterized by elemental analysis, IR, UV, and 1H-NMR spectroscopy. The structure of 3a was also determined by X-ray single-crystal diffraction. The thiosemicarbazone ligands are coordinated to dioxomolybdenum(VI) center through ONN set and the sixth coordinated site of the molybdenum is occupied by the second ligand (D). The in vitro antimicrobial activities of all thiosemicarbazones and their dioxomolybdenum(VI) complexes were tested against Candida albicans, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group. Firat University Scientific Research Projects Management Unit: 27965 This work was supported by the Scientific Research Projects Coordination Unit of Istanbul University (Project Number: 27965).

Three new chalcogenide vanadium complexes with a β-diketiminate ligand have been synthesized by reduction of the elemental chalcogens (S, Se, Te) with [(µ-η6:η6-toluene){V(nacnac)}2] (1) (nacnac = ...

The analysis of the use of chalcogenide metal chelates as single-source precursors of nanostructured materials has been carried out. The influence of the nature of the ligand, temperature, capping ...

A fluorescent gel has been prepared by deprotonation of non-fluorescent adipic acid derived ligand (H4AL) with LiOH followed by coordination with Cd(II) in DMF. The mechanism of gelation is examine...

8-Hydroxyquinolate complexes of lanthanide have a variety of applications in electroluminescent devices due to their unique luminescence properties. But, the simple 8HQ ligand has a tendency to form polynuclear complexes. However, linking several 8HQ units to a single moiety facilitates the formation of mononuclear complexes due to flexibility, preorganization, π-stacking and entropy effect. Mononuclear complexes of europium and terbium ions with a new chelator, [1,4,7-tris-{(5-methylene-8-hydroxyquinoline)-1,4,7-triazacyclononane}], embedded with these prerequisites are synthesized and characterized. Each Ln(III) is nine-coordinate and bonded to three sets of O,N-donors of 8HQ units and three water resulting in a pseudo-C3 symmetric tricapped trigonal prismatic geometry. In silico studies suggest that the metal ion can easily be encapsulated in the central cavity of the ligand without changing its basic structure. Interesting, diverse behavior was observed for photoluminescence spectral studies in solid and solution state. At room temperature, an antenna effect was observed for the complexes only in the powder form. The experimental photoluminescence studies have been explained with the help of TDDFT. The nature of bonding between the lanthanide and the ligand, interpreted by NBO and ETS-NOCV, suggest that the Ln-L bonds are ∼25% covalent. The Slater Condon parameters, spin-orbital coupling constants, and the nephelauxetic parameters were calculated from LF-DFT.