Modern spectroscopic and biological approach in the characterization of a novel 14-membered [N<Subscript>4</Subscript>] macrocyclic ligand and its transition metal complexes

A novel tetradentate nitrogen donor [N₄] macrocyclic ligand, i.e. 1,3,4,8,9,11-hexaaza-2,5,10,12-tetraoxo-7,14-diphenyl-cyclotetradecane (L), has been synthesized. Mn(II), Co(II), Ni(II) and Cu(II) complexes of this ligand have been prepared and subjected to elemental analyses, molar conductance measurements, magnetic susceptibility measurements, mass, ¹H-n.m.r. (Ligand), i.r., electronic, and e.p.r. spectral studies. On the basis of molar conductance the Mn(II), Co(II) and Cu(II) complexes may be formulated as [M(L)X₂] [where X = Cl⁻ & NO ₃ ⁻ ] due to their non-electrolytic nature in dimethylformamide (DMF). Whereas the Ni(II) complexes are 1:2 electrolytes and formulated as [Ni(L)]X₂. All the complexes are of the high spin type and are six/four coordinate. On the basis of i.r., electronic and e.p.r. spectral studies an octahedral geometry has been assigned to Mn(II) and Co(II), square planar for Ni(II) complexes, and tetragonal for Cu(II) complexes. The antimicrobial activities of the ligand and its complexes, as growth inhibiting agents, have been screened in vitro against several species of bacteria and plant pathogenic fungi.     

Tetraaza macrocyclic complexes: synthesis,spectral and antimicrobial studies

A tetradentate nitrogen donor [N₄] macrocyclic ligand, 1,3,7,9-tetraaza-2,8-dithia-4,10-dimethyl-6,12-diphenylcyclododeca-4,6,10,12-tetraene has been synthesized by using thiourea and benzoylacetone. Complexes of Mn(II), Co(II), Ni(II), and Cu(II) have been synthesized with this ligand and characterized by element chemical analysis, molar conductance, magnetic susceptibility, mass, ¹H nuclear magnetic resonance, Fourier transform–infrared, electronic, and electron paramagnetic resonance spectral studies. The molar conductance measurements of Mn(II), Co(II), and Cu(II) complexes in dimethyformamide correspond to nonelectrolytes, whereas Ni(II) complex is a 1: 2 electrolyte. The complexes are high-spin except for Ni(II) which is diamagnetic. Octahedral geometry has been assigned for Mn(II) and Co(II) complexes, square planar for Ni(II) and tetragonal geometry for Cu(II). The ligand and its complexes were screened in vitro against two pathogenic fungi (Fusarium moniliformae and Rhizoctonia solani) and bacteria (Staphylococcus aureus and Pseudomonas aeruginosa) to assess their growth inhibiting potential.     

Synthesis and Characterization of a Novel Macrocyclic vic‐Dioxime and Some of its Mono and Trinuclear Complexes

The (E, E)‐dioxime containing a dithia‐dioxa‐diaza macrocyclic moiety 5,6 : 11,12 : 17,18‐tribenzo‐2,3‐bis(hydroxyimino)‐1,4‐diaza‐7,16‐dithia‐10,12‐dioxacyclooctadecane ( H₂L ) has been synthesized in high yield by a 1 + 1 addition of cyanogendi‐N‐oxide with 2,3 : 8,9 : 14,15‐tribenzo‐1,16‐diamino‐4,13‐dithia‐7,10‐dioxahexadecane ( 3 ) which was obtained from condensation reaction with 2‐amino thiophenol and 1,2‐bis(2‐bromoethoxy)benzene, in dichloromethane at –10 °C. Two vic‐Dioxime ligands coordinate with Ni(II), Cu(II) and Co(III) through its hydroxyimino nitrogen donor atoms by the loss of the oxime protons. Homo and heterotrinuclear Cu^II₃ and Co^IIIPd^II₂ complexes of this ligand have been prepared; their two ligand molecules are connected via hydroxyimino or BF₂⁺‐bridging groups and two of the metal ions are coordinated by a diaza‐dithia mixed donor macrocyclic moiety. The macrocyclic ligand and its transition metal complexes have been characterized on the basis of ¹H‐, ¹³C‐NMR, IR and MS spectroscopy and elemental analysis data.     

Synthesis and Characterization of Metal Complexes of a New Unsymmetrical Tridentate NNS Schiff Base Ligand: X‐ray Crystal Structure Determination of Nickel(II) Complex

A new unsymmetrical tridentate NNS Schiff base ligand, 2‐(2‐nitrophenylthio)‐N‐((pyridine‐2‐yl)methylene)benzenamine (L), and its Mn(II ), Ni(II ), Cu(II ), and Zn(II ) complexes were synthesized. These compounds were characterized by different physicochemical and spectroscopic techniques. The molecular structure of [NiL₂ ](ClO₄ )₂ was determined by single‐crystal X‐ray diffraction. In this complex, two ligands coordinate through azomethine‐N, pyridine‐N, and thioether‐S, forming a mononuclear 6‐coordinate distorted octahedral geometry about a nickel.     

Physicochemical and Biological Characterization of Transition Metal Complexes with a Nitrogen Donor Tetra-dentate Novel Macrocyclic Ligand

A novel tetradentate nitrogen donor [N₄] macrocyclic ligand, i.e. 3,5,13,15,21,22-hexaaza-2,6,12,16-tetramethyl-4,14-dithia-tricyclo[15.3.1.1(7–11)]docosane-1(21),2,5,7,9,11(22),12,15,17,19-decaene, has been synthesized. Mn(II), Co(II), Ni(II) and Cu(II) complexes with this ligand have been prepared and subjected to elemental analyses, molar conductance measurements, magnetic susceptibility measurements, mass, ¹H-n.m.r. (Ligand), i.r., electronic, and e.p.r. spectral studies. On the basis of molar conductance the complexes may be formulated as [M(L)X₂] and [Ni(L)]X₂ [where M = Mn(II), Co(II) and Cu(II), and X = Cl⁻ and NO₃⁻] due to their nonelectrolytic nature in dimethylsulphoxide (DMSO). All the complexes are of the high spin type and are six coordinated. On the basis of i.r., electronic and e.p.r. spectral studies an octahedral geometry has been assigned to Mn(II) and Co(II), square planar for Ni(II) complexes, and tetragonal for Cu(II) complexes. The antimicrobial activities of the ligand and its complexes, as growth inhibiting agents, have been screened in vitro against several species of bacteria and plant pathogenic fungi.     

Synthesis,spectral, and antifungal studies of transition metal complexes with sixteen-membered hexadentate macrocylic ligand

A novel hexadentate nitrogen donor [N₆] macrocyclic ligand viz, 1,5,11,15,21,22-hexaaza-2,14-dimethyl-l4,12-diphenyltricyclo[15.3.1.I(7–11)]docosane[1,4,6,8,10(22)-11,14,16,18,20(21)]decaene (L), has been synthesised. The Co (II), Ni (II), and Cu (II) complexes with this ligand have been prepared and subjected to elemental analysis, molar conductance, magnetic susceptibility measurements, mass, ¹H NMR (ligand), IR, electronic, and ESR spectral studies and electrochemical investigation. On the basis of molar conductance the complexes can be formulated as [M(L)]X₂ (where M = Co (II), Ni (II), Cu (II) and X = Cl⁻ and NO₃⁻) due to their 1: 2 electrolytic nature in DMSO. All the complexes are of the high-spin type and are six-coordinated. On the basis of IR, electronic, and ESR spectral studies, an octahedral geometry has been assigned for the Co(II) and Ni(II) complexes, whereas a tetragonal geometry for the Cu(II) complexes was found. Antimicrobial activity of L and its complexes as growth inhibiting agents have been screened in vitro against two species (F. moniliformae and R. solani) of plant pathogenic fungi. The text was submitted by the authors in English.     

Single‐armed salamo‐like dioxime and its multinuclear Cu (II), Zn (II) and Cd (II) complexes: Syntheses,structural characterizations,Hirshfeld analyses and fluorescence properties

Three multinuclear Cu (II), Zn (II) and Cd (II) complexes, [Cu₂(L)(μ‐OAc)]·CHCl₂ ( 1 ), [Zn₂(L)(μ‐OAc)(H₂O)]·3CHCl₃ ( 2 ) and [{Cd₂(L)(OAc)(CH₃CH₂OH)}₂]·2CH₃CH₂OH ( 3 ) with a single‐armed salamo‐like dioxime ligand H₃L have been synthesized, and characterized by FT‐IR, UV–vis, X‐ray crystallography and Hirshfeld surfaces analyses. The ligand H₃L has a linear structure and C‐H···π interactions between the two molecules. The complex 1 is a dinuclear Cu (II) complex, Cu1 and Cu2 are all five‐coordinate possessing distorted square pyramidal geometries. The complex 2 also forms a dinuclear Zn (II) structure, and Zn1 and Zn2 are all five‐coordinate bearing distorted trigonal bipyramidal geometries. The complex 3 is a symmetrical tetranuclear Cd (II) complex, and Cd1 is a hexa‐coordinate having octahedral configuration and Cd2 is hepta‐coordinate with a pentagonal bipyramidal geometry, and it has π···π interactions inside the molecule. In addition, fluorescence properties of the ligand and its complexes 1 – 3 have also been discussed.     

Copper(II) Complexes of a Hexadentate Mixed‐Donor N3S3 Macrobicyclic Cage: Facile Rearrangements and Interconversions

The potentially hexadentate mixed‐donor cage ligand 1‐methyl‐8‐amino‐3,13,16‐trithia‐6,10,19‐triazabicyclo[6.6.6]eicosane (AMME‐N₃S₃sar; sar=sarcophagine) displays variable coordination modes in a complex with copper(II). In the absence of coordinating anions, the ligand adopts a conventional hexadentate N₃S₃ binding mode in the complex [Cu(AMME‐N₃S₃sar)](ClO₄)₂ that is typical of cage ligands. This structure was determined by X‐ray crystallography and solution spectroscopy (EPR and NIR UV/Vis). However, in the presence of bromide ions in DMSO, clean conversion to a five‐coordinate bromido complex [Cu(AMME‐N₃S₃sar)Br]⁺ is observed that features a novel tetradentate (N₂S₂)‐coordinated form of the cage ligand. This copper(II) complex has also been characterized by X‐ray crystallography and solution spectroscopy. The mechanism of the reversible interconversion between the six‐ and five‐coordinated copper(II) complexes has been studied and the reaction has been resolved into two steps; the rate of the first is linearly dependent on bromide ion concentration and the second is bromide independent. Electrochemistry of both [Cu(AMME‐N₃S₃sar)]²⁺ and [Cu(AMME‐N₃S₃sar)Br]⁺ in DMSO shows that upon reduction to the monovalent state, they share a common five‐coordinated form in which the ligand is bound to copper in a tetradentate form exclusively, regardless of whether a six‐ or five‐coordinated copper(II) complex is the precursor.     

Synthesis,structural characterization,EPR spectroscopy and Hirshfeld surface analysis of a novel Cu2+‐doped 3,14‐diethyl‐2,13‐diaza‐6,17‐diazoniatricyclo[16.4.0.07,12]docosane bis(perchlorate)

Cyclam derivatives and their metal complexes have been found to exhibit an anti‐HIV effect and stimulate the activity of stem cells from bone marrow. The strength of their binding to the CXCR4 receptor correlates with anti‐HIV and stem‐cell activities. Knowledge of the conformation and crystal packing of various macrocyclic metal complexes has become important in developing new effective anti‐HIV drugs. The synthesis and preparation of single crystals of a new Cu²⁺‐doped macrocyclic compound, (3,14‐diethyl‐2,6,13,17‐tetraazatricyclo[16.4.0.0^7,12]docosane)copper(II) bis(perchlorate)–3,14‐diethyl‐2,13‐diaza‐6,17‐diazoniatricyclo[16.4.0.0^7,12]docosane bis(perchlorate) (0.69/0.31), {[Cu(C₂₂H₄₄N₄)](ClO₄)₂}_0.69·(C₂₂H₄₆N₄²⁺·2ClO₄^?)_0.31, is reported. Characterization by X‐ray diffraction analysis shows that the asymmetric unit contains half of a centrosymmetric molecule. The macrocyclic ligand in the compound adopts the most stable trans‐III conformation. The Cu—N distances of 2.015 (3) and 2.047 (3) Å are normal, but the long axial Cu—O bond of 2.795 (3) Å may be due to a combination of the Jahn–Teller effect and the strong in‐plane ligand field. The crystal structure is stabilized by hydrogen bonding between secondary N—H groups, the N atoms of the macrocycle and the O atoms of the perchlorate anions. Hirshfeld surface analysis with 2D (two‐dimensional) fingerprint plots indicates that the main contributions to the crystal packing are from H…H (58.0%) and H…O/O…H (41.9%) interactions. Electron paramagnetic resonance (EPR) properties are also described.     

Synthesis,characterization, molecular docking and biological activity of 5,6-bis-(4-fluoro-phenyl)-3,4,7,8-tetraaza-bicyclo[8.3.1]tetradeca-1(13),4,6,10(14),11-pentaene-2,9-dione and its transition metal complexes

Macrocyclic Schiff base ligand through the condensation of 1,3-dicarbonyl-phenyl-dihydrazide with 4,4′-difluorobenzil and its Co(II), Ni(II), Cu(II) and Zn(II) metal complexes have been synthesized. The ligand and metal complexes were characterized by analytical and physicochemical methods. An octahedral geometry arising from coordination of N2O2 donor atoms from the macrocyclic framework has been proposed for all metal complexes. Synthesized ligand and metal complexes were investigated for in vitro antibacterial and antioxidant activity. Complex [Ni(C₂₂H₁₄N₄F₂O₂)(OCOCH₃)₂] has shown remarkable antibacterial activity (Minimum inhibitory concentration 8–16?μg/ml) comparable to commercial antibiotic Ciprofloxacin. Anticancer activity of synthesized compounds against Squamous Cell Carcinoma (SCC4), head and neck cancer cell line has also been studied at different concentrations and at different time points. Complexes [Co(C₂₂H₁₄N₄F₂O₂)(NO₃)₂] and [Cu(C₂₂H₁₄N₄F₂O₂)(OCOCH₃)₂] have shown remarkable anticancer results (IC₅₀ 31.1 and 43.1?μM) against the tested cell line in concentration dependent manner. Molecular docking studies were carried out to find the binding mode of the synthesized macrocyclic Schiff base ligand to Epidermal Growth Factor Receptor (EGFR) Kinase (PDB ID: 1M17).     

In vitro cytotoxic and apoptotic effect of vic‐dioxime ligand and its metal complexes

In this study, vic‐dioxime ligand, (1E,2E)‐2‐(hydroxyimino)‐N′‐[(1E)‐2‐oxo‐2‐phenylethylidene]ethanehydroximohydrazide (LH₂), and its Cu (II) and Ni (II) transition metal complexes were synthesized and characterized using analytical and spectroscopic techniques. Furthermore, in vitro cytotoxic and apoptotic effects of this vic‐dioxime ligand and its Cu (II) and Ni (II) complexes on Caco‐2 heterogeneous human epithelial colorectal adenocarcinoma cells were evaluated. The effect of the vic‐dioxime ligand and its Ni (II) and Cu (II) complexes in combination with Campto on the cells was also investigated. The cytotoxicity test was carried using the MTT assay, and the apoptotic effect was tested by DNA diffusion assay. Campto was used as a standard anti‐cancer drug, Caco‐2 cancer cells treated with dimethylsulfoxide acted as solvent control, and human peripheral lymphocytes were used as control. The ligand and its complexes exhibit concentration‐dependent cytotoxic and apoptotic behavior. The ligand induces the weakest cytotoxic and apoptotic effects on both Caco‐2 cancer cells and lymphocytes. The Ni (II) complex of ligand induces high cytotoxic and apoptotic effects on both Caco‐2 cancer cells and lymphocytes. The Cu (II) complex of ligand has high cytotoxic and apoptotic effects on Caco‐2, but weak cytotoxic and apoptotic effects on lymphocytes. The cytotoxic and apoptotic effects of the ligand and its Ni (II) and Cu (II) complexes were found to be concentration dependent, i.e. the higher the concentration is the more cytotoxic it will be. The present findings suggest that Cu (II) complex has the potential to act as a promising anti‐cancer compound against Caco‐2 colon cancer cells.     

Metal Complexes of Saccharin with the N-(2-hydroxyethyl)-ethylenediamine Ligand: Synthesis,Characterization and Spectroscopic Examination. Crystal Structures of trans- Bis(Saccharinato)Bis{N-(2-hydroxyethyl)-Ethylenediamine} copper(II) and Cadmium(II)

The novel transition metal saccharinato complexes of N-(2-hydroxyethyl)-ethylendiamine (HydEt-en) have been synthesized and characterized by elemental analyses, magnetic moments, UV-Vis and IR spectra. Coordination behaviour of HydEt-en has been studied. The Mn(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) form mononuclear complexes, while the Fe(II) and Co(II) complexes are dimeric. The crystal structures of the [Cu(sac)₂(HydEt-en)₂] and [Cd(sac)₂(HydEt-en)₂] complexes, where sac is the deprotonated form of saccharin, were determined by x-ray diffraction. The metal ions are octahedrally coordinated by these ligands. The amine ligand acts as a bidentate N-donor ligand and its ethanol group is not involved in coordination. The sac ions coordinate through the deprotonated N as a monodentate ligand. The NH and OH groups of the amine ligand are involved in intra- and intermolecular hydrogen bonding with the carbonyl and sulphonyl oxygens of the sac ions to form a three-dimensional infinite network.     

Synthesis and Characterization of New Macrocyclic Cu（Ⅱ） Complexes from Various Diamines, Copper（Ⅱ） Nitrate and 1,4-Bis（2-formylphenoxy）butane

Six new macrocyclic complexes were synthesized by a template reaction of 1,4-bis（2-formylphenoxy）butane with diamines and Cu（NO3）2·3H2O and their structures were proposed on the basis of elemental analysis, FT-IR, UV-Vis, magnetic susceptibility measurements, molar conductivity measurements and mass spectra. The metal to ligand molar ratios of the Cu（Ⅱ） complexes were found to be 1 ： 1. The Cu（Ⅱ） complexes are 1 ： 2 electrolytes as shown by their molar conductivities （∧m） in DMF at 10^-3 mol·L^-1. Due to the existence of free ions the Cu（Ⅱ） complexes are electrically conductive. Their configurations were proposed to be probably distorted octahedral.     

Spectral and Structural Studies of the Copper(II) Complexes of 3, 4‐Hexanedione Bis(3‐azacyclothiosemicarbazones)

Copper(II) complexes of 3, 4‐hexanedione bis(piperidyl‐ and bis(hexamethyleneiminylthiosemicarbazone), H₂Hxpip and H₂Hxhexim, respectively, have been prepared and studied spectroscopically. The bis(thiosemicarbazones) have been characterized by their melting points, as well as IR, electronic and ¹H NMR spectra. Upon formation of their copper(II) complexes, loss of the hydrazinic hydrogen atoms occurs, and the ligands coordinate as dianionic, tetradentate N₂S₂ ligands. The crystal structures of H₂Hxpip, its 4‐coordinate copper(II) complex, [Cu(Hxpip)], and the related [Cu(Hxhexim)] have been determined by single crystal x‐ray diffraction. The nature of the four‐coordinate copper(II) complexes have also been characterized by ESR, IR, and electronic spectroscopy, as well as magnetic moments and elemental analyses.     

Coordination chemistry of copper(II) complexes with N4, N4S2, and N4O2 donor macrocyclic ligands: Biological aspects—antifungal, synthesis, spectral studies, and magnetic moments

Three macrocyclic ligands and their complexes with copper(II) salts (with anions Cl⁻, NO ₃ ⁻ , and NCS⁻) were prepared and investigated using a combination of microanalytical analysis, melting point, molar conductance measurement, magnetic susceptibility measurement, and electronic, IR and ESR spectral studies. Ligands L¹, L², and L³ having N₄, N₄O₂, and N₄S₂ core, respectively, and all the donor atoms of these ligands are bonded with Cu, which is confirmed by a seven-line pattern observed at half-field in the frozen (H₂O: MeOH = 10: 1 at pH 10) solution ESR spectrum. The polycrystalline ESR data (g _∥ = 2.20–2.27, g _⊥ = 2.01–2.05, and A _∥ = 120–270) of all the complexes together with the high asymmetry geometry suggest that all complexes appear to be near the static distortion (CuN₄O₂ and CuN₄S₂ chromophore geometry). The electronic spectra of the complexes involve two bands at the same intensity corresponding to a cis-distorted octahedral geometry. A common structural feature of both ligand L² and ligand L³ is that two different donor atoms at five-membered heterocyclic aromatic ring due to this N₄O₂ and N₄S₂ chromophore form stable six-membered chelate rings with metals via these two, Cu-O and Cu-S, new interactions comparatively to the first macrocyclic ligand, which has four-membered N,N′-chelate rings. The cyclic voltammetric studies point to a two-step electron transfer indicating the reduction of the two copper atoms to copper(I), i.e., Cu(III)Cu(II) ⇄ Cu(II)Cu(I) ⇄ Cu(I)Cu(0). The molar conductance for the complexes corresponds to 1: 2 and is nonelectrolyte in nature. The magnetic moment (μ_eff) of the complexes lie in the range between 1.80–1.96 μ_B. Finally, these complexes were screened for their antimicrobial activity against Aspergillus-niger of fungal strains. The text was submitted by the authors in English.     

Comparison of two polymeric transition metal complexes with 1,4‐benzenedicarboxylate ions as bridging ligands, [Co(C8H4O4)(C12H8N2)(H2O)] and [Cu(C8H4O4)(C10H9N3)]·H2O

The title complexes, catena‐poly[[aqua(1,10‐phenanthroline‐κ²N,N′)­cobalt(II)]‐μ‐benzene‐1,4‐di­carboxyl­ato‐κ²O¹:O⁴], [Co(C₈H₄O₄)(C₁₂H₈N₂)(H₂O)], (I), and catena‐poly[[[(di‐2‐pyridyl‐κN‐amine)copper(II)]‐μ‐benzene‐1,4‐di­carboxyl­ato‐κ⁴O¹,O^1′:O⁴,O^4′] hydrate], [Cu(C₈H₄O₄)(C₁₀H₉N₃)]·H₂O, (II), take the form of zigzag chains, with the 1,4‐benzene­di­carboxyl­ate ion acting as an amphimonodentate ligand in (I) and a bis‐bidentate ligand in (II). The Co^II ion in (I) is five‐coordinate and has a distorted trigonal–bipyramidal geometry. The Cu^II ion in (II) is in a very distorted octahedral 4+2 environment, with the octahedron elongated along the trans O—Cu—O bonds and with a trans O—Cu—O angle of only 137.22 (8)°.     

Studies on mononuclear transition metal chelates derived from a novel ( E,E )-dioxime: synthesis,characterization and biological activity

A novel vic-dioxime ligand with a thiourea moiety, (4E,5E)-1,3-bis{4-[(4-bromophenylamino)methylene]phenyl}-2-thiooxaimidazoline-4,5-dione dioxime (4) (bmdH₂) has been synthesized from N,N′-bis{4-[(4-bromophenylamino)methylene]phenyl}thiourea and (E,E)-dichloroglyoxime. The bmdH₂ ligand (4) forms transition metal complexes [M(bmdH)₂] with a metal?:?ligand ratio of 1?:?2 with M?=?Ni(II), Co(II), and Cu(II). The mononuclear Ni(II), Co(II) and Cu(II) complexes, [Ni(bmdH)₂] (5), [Co(bmdH)₂] (6) and [Cu(bmdH)₂] (7) have the metal ions coordinated through the two N,N atoms, as do most vic-dioximes. Elemental analyses, molar conductivity, magnetic susceptibility, IR, ¹H NMR spectra, and UV-Visible spectroscopy were used to elucidate the structures of the ligand and its complexes. Conductivity measurements have shown that the mononuclear complexes are non-electrolytes. In addition, the ligands and metal complexes were screened for antibacterial and antifungal activities by agar well diffusion techniques using DMF as solvent.     

Design of phenanthrimidazole-pendant cyclam and cyclen macrocyclic complex ligands as inorganic hosts: Photophysics,electrochemistry, and bimetallic complex formation

Novel ruthenium(II)bpy complexes of the phenanthrimidazole-pendant cyclen and cyclam macrocyclic ligands were synthesized as inorganic host molecules. Inorganic host design was planned as a “complex ligand” form because of its tetraaza macrocyclic unit, which has the ability to coordinate to the metals. Photophysical properties and metal selectivity of inorganic hosts RuL1A and RuL2 complex ligands were investigated by UV-vis and fluorescence spectroscopy in aqueous medium. Among Ag(I), Li(I), Na(I), K(I), Cd(II), Cr(II), Fe(II), Hg(II), Ni(II), Pb(II), Zn(II), Cu(II), Mn(III), and Co(III) metal ions, Fe(II) addition causes spectral changes for both RuL1A and RuL2 complex ligands. Electrochemical studies were performed for RuL1B and also for cis-[Ru(bpy) ₂ Cl ₂ ] . Bimetallic complexes [[Ru(bpy)₂([Ni(2-(4-((1,4,8,11-tetraazacyclotetradecan-1-yl)methyl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline])](ClO₄)₄, RuL1-NiA and [Ru(bpy)₂([Ni(2-(4-((1,4,8,11-tetraazacyclotetradecan-1-yl)methyl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline])]Cl₄, RuL1-NiB solid complexes were also obtained by the reaction of the RuL1B and Nickel(II).     

Direct Synthesis of Porous Nanorod‐Type Graphitic Carbon Nitride/CuO Composite from Cu–Melamine Supramolecular Framework towards Enhanced Photocatalytic Performance

Facile and direct synthesis of porous nanorod‐type graphitic carbon nitride/CuO composite ( CuO‐g‐C₃N₄ ) has been achieved by using a Cu–melamine supramolecular framework as a precursor. The CuO‐g‐C₃N₄ nanocomposite demonstrated improved visible‐light‐driven photocatalytic activities. The results indicate that metal–melamine supramolecular frameworks can be promising precursors for the preparation of efficient g ‐C₃N₄ nanocomposite photocatalysts.     

[Cu(bpp)2(bpdc)(H2O)2]×2H2O and [Cu(bpp)2](tdc)×7.5H2O的合成、晶体结构和热稳定性

在室温下, 由Cu(NO3)2 、1,3 -二（4 -吡啶基）丙烷(bpp)、4,4 ’ -联苯二甲酸(H2bpdc)和2,5-噻吩二甲酸(H2tdc)制备出两种新型铜( II)配位聚合物[Cu(bpp)2(bpdc)(H2O)2]n·2nH2O, 1 和[Cu(bpp)2]n·n(tdc) 7.5nH2O, 2。两个配位聚合物均为一维线型结构,铜原子均采取变形的八面体结构,在轴线方向上的两个水分子与铜原子存在较弱的配位作用。在配合物1中,两个bpdc羧酸根离子与铜原子配位,而2中的tdc羧酸离子没有与铜原子键合,只是作为反离子平衡电荷。在两个产物中, 配体bpp具有不同的构象。热重分析表明配合物1与2分别在110°C和160°C以下是稳定的。