Synthesis and characterization of amantadinium iodoacetatobismuthate,a hybrid compound with mixed iodide–carboxylate anions

The amantadinium iodoacetatobismuthate(III) [C₁₀H₁₅NH₃·(CH₃)₂CO]₂[BiI_3.67(CH₃COO)_1.33] is a new hybrid halometallate with iodide ions partially replaced by oxygen-containing acetates to form stronger interaction between the anionic and cationic substructures. The title compound as well-shaped orange-red crystals was synthesized by a facile reaction in acetone solution in the presence of glacial acetic acid. The crystal structure of the compound consists of the infinite anionic chains [BiI_3.67(CH₃COO)_1.33]^2– and the countercations [C₁₀H₁₅NH₃·(CH₃)₂CO]+; according to the optical absorption data, the test compound is a semiconductor with a band gap of 2.06 eV.     

Synthesis and spectroscopic characterization of a porphyrin–dibenzimidazole dinucleating ligand and its cobalt–copper heterodinuclear complex as a cytochrome C oxidase active site model

A new dinucleating ligand consisting of a tetraphenylporphyrin derivative covalently linked with di(2-benzimidazolylmethyl)imine and its homodinuclear Co–Co and heterodinuclear Co–Cu complexes were synthesized and spectroscopically characterized. The heterobimetallic Co–Cu complex, a cytochrome c oxidase active site model, can be obtained by a simple metathesis reaction of the homodinuclear complex with the metal salt in high yield.     

Synthesis and characterization of a tetranuclear copper(Ⅱ) complex with a chiral Schiff base ligand

The title complex l-[Cu^Ⅱ₄（Hvap）₂（vap）₂（MeOH）₂]（CIO₄）₂ 1 has been synthesized and characterized by EA. IR,TGA,solid-state CD spectra and X-ray single-crystal analyses（l-H₂vap’.a Schiff base ligand derived from the condensation of o-vanillin and l-2-amino-3-phenyl-l-propanol）.Complex 1 crystallizes in monoclinic system,chiral space group P2₁ with a =10.4257（18）.b = 21.695（4）,c = 15.721（3）A,β= 94.443（3）.V= 3545.1（11） ³,Z=2,Cu₄C₇₀H₇₈N₄O₂₂Cl₂.Mr= 1652.42,D_c= 1.548 g/cm³, F（000）= 1704 andμ（MoKα） = 1.338 mm^-1.The final R = 0.0682 and wR = 0.1420 for 6170 observed reflections with I > 2σ（I） and R = 0.1775 and wR = 0.1830 for all data.The structure of complex 1 contains a boat-shaped(Cu₄O₄} motif.The solid-state CD spectra confirm the chiral nature of complex 1.     

Synthesis,characterization and spectroscopic study of riboflavin–molybdenum complex

A riboflavin–molybdenum [(RF)–Mo(V)] complex in powder form was synthesized and characterized by elemental analysis, UV–Vis, IR, NMR spectroscopy and X-ray diffraction. During the synthesis of this metal complex, another metal complex [Mo₂O₄(H₂O)₆]²⁺ was also synthesized and characterized. The results of X-ray diffraction study have revealed an orthorhombic cubic system for the RF–Mo complex. The steady state absorption and emission studies of RF and RF–Mo in hydrochloric acid (HCl) of varying pH were investigated. The steady state absorption with RF–Mo showed distinct changes in the absorption spectra of RF after complexation. The steady state emission results, consistent with prior reports showed fluorescence quenching in the aqueous solution of both RF and RF–Mo in HCl with the proton acting as a quencher. The Stern–Volmer constant observed was 108.79 and 98.68 for RF and RF–Mo, respectively. The binding constant for RF–Mo complex was found to be 1.201 × 10³ M⁻¹ at 298 K.     

Synthesis,characterization and antibacterial activity of a curcumin–silver(I) complex

The current study reports the synthesis of a curcumin–silver(I) complex and its preliminary tests against four bacterial strains viz. Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Bacillus cereus using agar well diffusion method. The results were compared with curcumin by testing it in parallel with the sample. Curcumin showed zones of inhibition against all tested strains of bacteria. Among all bacterial strains, S. aureus was the most sensitive to curcumin with zone of inhibition of 12.2 mm. However, the curcumin–Ag(I) complex did not show the expected enhanced activity against all bacteria. This is perhaps due to the replacement of curcumin phenolic protons by silver ions which might have suppressed the antibacterial property of curcumin. The current research findings suggest that while synthesizing curcumin–metal complexes, the phenolic heads may either be left unaltered or need to be replaced by better substituents than hydroxy groups. Based on the current findings, biologically enhanced models have been provided as future recommendations.     

Synthesis,characterization of neodymium chloride complex of amine-bis(phenolate) ligand and its reactivity in the ring-opening polymerization of ε-caprolactone

The neodymium chloride complex[Nd(ONN'O)Cl(THF)]_2 supported by amine-bis(phenolate) ligand was synthesized by the metathesis reaction of anhydrous NdCl_3 with Li_2(ONN'O)[H_2ONN'O = Me_2NCH_2CH_2N(CH_2-3-Bu_2~t-5-Me-C_6H_2OH)_2]in high yield.X-ray structural determination shows[Nd(ONN'O)Cl(THF)]_2 complex consists of two seven-coordinate neodymium centers linked throughμ-Cl bridges.And this complex was successfully used to initiate the ring-opening polymerization(ROP) ofε-caprolactone.     

Synthesis,characterization, luminescent,and catalytic performance of a dinuclear triazenido–silver complex

Our group has developed a series of molecular electrocatalysts for hydrogen generation based on triazenido–metal complexes (such as cobalt, copper, etc.). In this paper, we present the electrocatalytic performance of a new dinuclear silver complex, [Ag₂(L)₂], formed by reaction of the triazenido ligand, 1-[(2-carboxyethyl)benzene]-3-[benzimidazole]triazene (HL) with AgNO₃. The electrocatalytic systems based on this silver complex can afford 91.23 and 473 moles of hydrogen per mole of catalyst per hour (mol H₂/mol catalyst/h) from acetic acid at overpotential (OP) of 991.6 mV and an aqueous buffer at an OP of 837.6 mV, respectively. Electrochemical investigations show both the silver center and the triazenido ligand, HL, play important roles in determining the catalytic activities of the electrocatalytic system. Additionally, the triazenido ligand (HL) can serve as a fluorescent sensor for Ag⁺.     

Synthesis and characterization of a dipeptide–copper(II)– 2-aminomethylbenzimidazole ternary complex

A new ternary complex [Cu(glygly)(AMBZ)(H₂O)]Cl·H₂O (1) (glygly?=?glycylglycine anion, AMBZ?= 2-aminomethylbenzimidazole) has been prepared and characterized by single-crystal X-ray diffractometry and ESR, electronic and IR spectroscopy. The copper(II) ion has a slightly distorted square-pyramidal coordination, being equatorially coordinated by the bidentate 2-aminomethylbenzimidazole and the bidentate glycylglycine anion and axially by a water molecule. The individual complex molecules are hydrogen bonded to their neighbors, forming a polymeric hydrogen-bonded lattice. Spectroscopic data are in accordance with the crystal structure.     

Synthesis and characterization of yttrium,europium, terbium and dysprosium complexes containing a novel type of triazolyl–oxazoline ligand

We report the synthesis of a novel type of bidentate chiral ligand which structurally derives from the association of a 1,2,3-triazole ring with a chiral oxazoline. Yttrium and lanthanide nitrato-complexes of the new triazolyl–oxazoline ligand were prepared and characterized. The coordination mode of the ligand was ascertained by means of DFT calculations. Trivalent europium and terbium derivatives resulted appreciably photoluminescent upon excitation with UV light, showing the typical ⁵D₀ → ⁷F_J and ⁵D₄ → ⁷F_J emissions, respectively. These species were successfully used for the preparation of luminescent-doped polymeric materials.     

Synthesis,characterization and reactivity of a neutral antimony(Ⅲ) complex

Pincer complexes are widely used in organometallic and coordination chemistry.The role of antimony as a central donor atom in pincer ligands has been extensively explored in recent years.Although phenylenediamine derived PXP(X=B,Al,C,Si,Ge,Sn,N) type ligands exhibit diverse reactivity,analogues species based on antimony have been reported less frequently.Herein,we report a new PSbP complex and evaluate its reactivity.These species will broaden the family of phenylenediamine derived pincer complexes.     

Synthesis,structure and fluorescence of a novel three-dimensional inorganic–organic hybrid polymer constructed from trimetallic clusters and mixed carboxylate ligands

A new inorganic–organic hybrid framework coordination polymer, Cd₃(BDC)_0.5(BTC)₂(DMF)(H₂O)·3DMF·H₃O·H₂O 1, in which two carboxylate ligands, 1,4-benzenedicarboxylic acid (H₂BDC) and 1,3,5-benzenetricarboxylic acid (H₃BTC), coordinate with cadmium ions, has been synthesized under mild conditions and its structure solved by single-crystal X-ray diffraction (XRD) analysis. Polymer 1 crystallizes in the monoclinic system, space group P2₁/c (No. 14) with a=15.750(3) Å, b=14.501(3) Å, c=19.363(4) Å, β=113.67(3)°, V=4050.4(14) Å³, Z=4, R1=0.0374 and wR2=0.1148. Its structure revealed that the nine vertices of the secondary building units are linked by benzene rings from both H₃BTC and H₂BDC ligands to form a 3D network with 10×10 Å channels along [001] direction. Complex 1 is characterized by inductively coupled plasma analysis, powder XRD, infrared spectroscopy and thermogravimetric analysis. Polymer 1 exhibits intense fluorescence at 358 and 377 nm with λ_excitation=208 nm in the solid state at room temperature.     

X-ray crystal structure and magnetic properties of a heteronuclear copper–neodymium unsaturated carboxylate complex

A novel heteronuclear complex, [NdCuL₅(EtOH)(phen)]₂(HL = -methylacrylic acid, phen = 1,10-phenanthroline), was prepared and its molecular structure determined by X-ray analysis. The complex is a tetranuclear molecule. Magnetic properties of the complex were also measured and are discussed.     

Synthesis and characterization of a novel organic–inorganic hybrid supramolecular recognition material and its selective adsorption for cesium

To separate Cs(I) from highly active liquid waste, a macroporous silica-based 25, 27-bis(iso-propyloxy)calix[4]arene-26,28-crown-6 (BiPCalix[4]C6) supramolecular recognition material, BiPCalix[4]C6/SiO₂–P, was synthesized and characterized by SEM, FT-IR, and TG-DSC. The adsorption properties of BiPCalix[4]C6/SiO₂–P and a macroporous polymer-based supramolecular recognition composite, BiPCalix[4]C6/XAD-7, were compared. It was found that BiPCalix[4]C6/SiO₂–P exhibited better adsorption ability and faster adsorption dynamics than BiPCalix[4]C6/XAD-7. The adsorption isotherm of Cs(I) onto BiPCalix[4]C6/SiO₂–P was studied at 298 K and it was well described by Langmuir isotherm model. The complex composition between BiPCalix[4]C6/SiO₂–P and Cs(I) was determined as 1:1 type by investigating the effect of the concentrations of BiPCalix[4]C6, Cs(I), and H⁺ on the adsorption. Meanwhile, the selectivity of BiPCalix[4]C6/SiO₂–P towards Na(I), K(I), Rb(I), Cs(I), Sr(II), Ba(II), Ru(III), Mo(VI), La(III), and Y(III) was investigated.     

Nanocrystalline hydroxyapatite powders by a chitosan–polymer complex solution route: Synthesis and characterization

Nanocrystalline hydroxyapatite (HAp) powders were successfully synthesized by a simple method using chitosan–polymer complex solution. To obtain HAp nanopowders, the prepared precursor was calcined in air at 400–800 °C for 2 h. The phase composition of the calcined samples was studied by X-ray diffraction (XRD) technique. The XRD results confirmed the formation of HAp phase with a small trace of monotite phase. With increasing calcination temperature, the crystallinity of the HAp increased, showing the hexagonal structure of HAp with the lattice parameter a in a range of 0.94030–0.94308 nm and c of 0.68817–0.68948 nm. The particle sizes of the powder were found to be 55.02–73.36 nm as evaluated by the XRD line broadening method. The chemical composition of the calcined powders was characterized by FTIR spectroscopy. The peaks of the phosphate carbonate and hydroxyl vibration modes were observed in the FTIR spectra for all the calcined powders. TEM investigation revealed that the prepared HAP samples consisted of rod-like nanoparticles having the particle size in the range of 100–300 nm. The corresponding selected-area electron diffraction (SAED) analysis further confirmed the formation of hexagonal structure of HAp.     

Synthesis,X-ray crystal structure,DFT calculations,spectroscopic characterization and redox behaviour of a rhodium(III) complex of an anthracene–pyridylhydrazone ligand

Transition Metal Chemistry - A pyridylhydrazone incorporating an anthracene moiety, designated as HLAnc, has been synthesized in order to examine its coordination behaviour towards rhodium(III)....     

Synthesis,structure and properties of a series of scorpionate oxovanadium(IV)–carboxylate complexes

A series of oxovanadium(IV) complexes: TpVO(pzH)(2,4-Cl–C₆H₃–OCH₂COO) (1), TpVO(pzH)(C₆H₅–OCH₂COO) (2), TpVO(pzH)(p-Cl–C₆H₄–COO) (3), TpVO(pzH)(3,5-NO₂–C₆H₃–COO) (4), Tp∗VO(pzH∗)(p-Cl–C₆H₄–COO) (5) and Tp∗VO(pzH∗)(p-Cl–C₆H₄–COO) · CH₃OH (6) (Tp = hydrotris(pyrazolyl)borate, pzH = pyrazole, Tp∗ = hydrotris(3,5-dimethylpyrazolyl)borate, pzH∗ = 3,5-dimethylpyrazole) were synthesized and their crystal structures were determined by X-ray diffraction. In all the complexes, the vanadium ions are in a distorted-octahedral environment with a N₄O₂ donor set. Hydrogen bonding interaction exists in each complex. Complexes 1 and 2 are hydrogen-bonded dimers. Dimeric units of 2 are connected to one another via weak inter-molecular C–H···O interactions to form a 2D network on the bc-face. In 3–6 there exist intramolecular N–H···O hydrogen bonds between the neutral pyrazole/3,5-dimethylpyrazole and the uncoordinated carboxyl oxygen atom. In addition, the catalytic activity of complex 2 in a bromination reaction in phosphate buffer with phenol red as a trap was evaluated by UV–Vis spectroscopy. Furthermore, the elemental analyses, IR spectra and thermal stabilities were recorded.     

Synthesis and characterization of praseodymium-2-hydroxypropyl-β-cyclodextrin inclusion complex

Journal of Radioanalytical and Nuclear Chemistry - The inclusion complex of PrCl3-XH2O-2-hidroxypropyl-β-cyclodextrin (Pr-2HPβCD) was prepared to increase the solubility and stability of...