Synthesis and structure of Mn(II) and Zn(II) complexes containing 1,10-phenanthroline unit

The Mn(II) and Zn(II) complexes of N,N′-diisopropyl-1,10-phenanthroline-2,9-dimethanamine have been synthesised, and the structure of the two complexes have been studied by X-ray crystallography.     

Nucleic acid biosensor for detection of hepatitis B virus using 2,9-dimethyl-1,10-phenanthroline copper complex as electrochemical indicator

In this study, an electrochemical DNA biosensor was developed based on the recognition of target DNA by hybridization detection. The study was carried out using glassy carbon electrode (GCE) modified with lable-free 21-mer single-stranded oligonucleotides related to hepatitis B virus sequence via covalent immobilization and [Cu(dmp)(H₂O)Cl₂] (dmp = 2,9-dimethyl-1,10-phenanthroline) as an electrochemical indicator, whose sizes are comparable to those of the small groove of native double-duplex DNA. The method, which is simple and low cost, allows the accumulation of copper complex within the DNA layer. Electochemical detection was performed by cyclic voltammetry and differential pulse voltammetry over the potential range where the [Cu(dmp)(H₂O)Cl₂] was active. Numerous factors affecting the probe immobilization, target hybridization, and indicator binding reactions were optimized to maximize the sensitivity and speed the assay time. With this approach, a sequence of the hepatitis B virus could be quantified over the ranges from 8.82 × 10⁻⁸ to 8.82 × 10⁻⁷ M with a linear correlation of r = 0.9937 and a detection limit of 7.0 × 10⁻⁸ M. The [Cu(dmp)(H₂O)Cl₂] signal observed from probe sequence before and after hybridization with four bases mismatch containing sequence is lower than that observed after hybridization with complementary sequence.     

Synthesis and crystal structure of a Cu(II) complex with mixed malonate/1,10-phenanthroline ligands

A Cu(II) complex with mixed ligands, [Cu₃(mal)₃(phen)₃(H₂O)₂]?·?11H₂O (mal?=?malonate, phen?=?1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR, UV, electron paramagnetic resonance (EPR) and luminescence spectra and single-crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group Cc with a?=?13.1631(10)?Å, b?=?20.1089(10)?Å, c?=?20.1267(13)?Å, β?=?103.500(3)°, V?=?5180.2(6)?ų, Z?=?4, and R ₁?=?0.0476 for 7993 observed reflections. In the complex, one Cu is coordinated by a mal dianion and a phen molecule, exhibiting N₂O₂ square-planar geometry, while the other two Cu atoms are coordinated, respectively, by a mal dianion, a phen and water molecules, exhibiting N₂O₃ square pyramidal coordination geometry.     

Displacement reactions of 2-chloro- and 2,9-dichloro-1,10-phenanthroline: synthesis of a sulfur-bridged bis-1,10-phenanthroline macrocycle and a 2,2′-amino-substituted-bis-1,10-phenanthroline

The synthesis and structural assignments of 9-chloro-1,1-phenanthroline-2(1H)-thione and 1,10-dihydro-1,10-phenanthroline-2,9-dithione have been accomplished. The sulfur-bridged bis-1,10-phenanthroline macrocycle was readily prepared by heating the thione or equimolar amounts of the dithione and 2,9-dichloro-1,10-phenanthroline in diphenyl ether. Displacements of 2-chloro- or 2,9-dichloro-1,10-phenanthroline with N,N-dimethylethylenediamine afforded the corresponding amine and diamino analogues. An amino-substituted-2,2′-bis-1,10-phenanthroline has been prepared.     

Crystal structure and physico-chemical properties of diaquabis(1,10-phenanthroline)manganese(II) disaccharinate monohydrate

A novel manganese complex, [Mn(phen)₂(H₂O)₂](sac)₂·H₂O, was synthesized by the reaction of [Mn(sac)₂(H₂O)₄]·2H₂O with 1,10-phenantroline in aqueous solution and characterized by elemental analysis, IR spectral evidence, magnetic measurements, thermal analysis and single crystal X-ray diffraction. The compound crystallizes in triclinic system, space group P-1, with Z=2. The saccharinate ions do not coordinate the central metal, instead are present as the complementary anions. In the complex cation, Mn(II) is coordinated by two phen and two aqua ligands, and exhibits a distorted octahedral coordination with a high-spin configuration. The presence of lattice and coordinate water molecules are also confirmed by thermal analysis and IR spectroscopy.     

Synthesis,characterization, and crystal structure of a copper(II) complex of 1,10-phenanthroline and succinate

A mixed ligand complex of Cu(II) with 1,10-phenanthroline and succinate has been synthesized from the reaction of hydrated copper nitrate, succinate, and 1,10-phenanthroline. The nature of bonding and the structure of the complex were characterized by elemental analyses, infrared spectrum, TGA/DTA, and X-ray diffraction. The crystal crystallizes in triclinic space group P 1. The complex is polymeric and the geometry around each copper varies from square planar to distorted square pyramidal or octahedral. Each copper coordinates two oxygens of succinate and two nitrogens of 1,10-phenanthroline. The thermal decomposition of the complex has also been studied by TGA and DTA under inert atmosphere.     

Spectrothermal studies of 1,10-phenanthroline complexes of Co(II), NI(II), Cu(II) and Cd(II) orotates

The 1,10-phenanthroline (phen) complexes of Co(II), Ni(II), Cu(II) and Cd(II) orotates were synthesized and characterized by elemental analysis, magnetic susceptibility, spectral methods (UV-vis and FTIR) and thermal analysis techniques (TG, DTG and DTA). The Co(II), Ni(II), Cu(II) and Cd(II) ions in diaquabis(1,10-phenanthroline)metal(II) diorotate octahedral complexes [M(H₂O)₂(phen)₂](H₂Or)₂·nH₂O (M=Co(II), n=2.25; Ni(II), n=3; Cu(II) and Cd(II), n=2) are coordinated by two aqua ligands and two moles of phen molecules as chelating ligands through their two nitrogen atoms. The monoanionic orotate behaves as a counter ion in the complexes. On the basis of the first DTG_max, the thermal stability of the hydrated complexes follows the order: Cd(II), 68°C 68°C     

Concentration-controlled Zn(II) compounds constructed from N-tosyl-L-glutamic acid and 1,10-phenanthroline

By controlling the concentration of the reaction system, two zinc(II) complexes, [Zn₂(tsgluO)₂(phen)₂]_n (1) and [Zn₂(tsgluO)₂(phen)₂(H₂O)₂] (2) (H₂tsgluO = N-tosyl-L-glutamic acid, phen = 1,10-phenanthroline), have been synthesized under hydrothermal conditions and characterized by elemental analysis, infrared spectra, thermogravimetric analysis, and single-crystal X-ray diffraction. Complexes 1 and 2 both crystallize in the triclinic space group P-1. Complex 1 exhibits a 1-D double-chain structure. Complex 2 has a dinuclear structure which is extended by hydrogen-bonding interactions to form a 2-D supramolecular network. The structural difference indicates that the concentration plays a crucial role in modulating structures of coordination complexes. The two compounds also show intense fluorescence at room temperature.     

Synthesis,structure and luminescent properties of zinc(II) and Hg(II) complexes with substituted 1,10-phenanthroline

Two d¹⁰ group 12 metal complexes, 2-(2-methoxyphenyl)-1,10-phenanthroline zinc dichloride (2a) and 2-(2-methoxyphenyl)-1,10-phenanthroline mercury dichloride (2b) were synthesized and characterized by IR, ¹H and ¹³C NMR as well as elemental analysis. Structure of 2b in the solid state was determined by single-crystal X-ray crystallography, revealing that 2b is four-coordinate in a distorted tetrahedral geometry with the methoxy group uncoordinated. Luminescent properties of 2a and 2b in solution and the solid state were studied.     

Syntheses,spectral characterization,thermal properties and DNA cleavage studies of a series of Co(II), Ni(II) and Cu(II) polypyridine complexes with some new imidazole derivatives of 1,10-phenanthroline

In the present study three new imidazole derivatives of phen, 2-(4-hydroxy-3,5-diiodophenyl) imidazo[4,5-f][1,10]phenanthroline L¹, 2-(2-hydroxy-3,5-diiodophenyl)imidazo[4,5-f][1,10]phenanthroline L², 2-(4-hydroxy-5-iodo-3-methoxyphenyl)imidazo[4,5-f][1,10]phenanthroline L³ and their nine new polypyridine complexes[M(N–N)₂(L^1–3)](OAc)₂·(nH₂O) where M is Ni(II), Co(II) and Cu(II) and where (N–N)₂ is 2,2′-bipyridine (bpy)₂ or 1,10-phenanthroline (phen)₂ have been synthesized from the reaction of the metal precursor complexes [M(phen)₂(OAc)₂]·(nH₂O) and [M(bpy)₂(OAc)₂]·(nH₂O) with the respective ligands in ethanol and water. The structures of the compounds were determined with the aid of elemental analysis and FT-IR, UV–Vis, ¹H NMR, ESR spectroscopic methods, magnetic measurements and conductance measurements, further analyzed by powder XRD and thermal studies. Elemental analysis data suggested that the complexes have a 1:2:1 molar ratio among the metal and phen or bpy and L¹/L² or L³ ligands. The spectral data show that all the complexes were six coordinated and possess octahedral geometry around the metal ions. The X-band ESR spectrum of the Cu(II) in DMSO solution at room temperature was recorded and observed anisotropic g values indicate the presence of metal ion in an octahedral environment. The powder XRD patterns of complexes recorded in the range (2θ = 0–80°) and average crystallite size (d_XRD) was calculated using Scherrer’s formula. Thermal decomposition profiles of complexes show high decompound temperatures indicating a good thermal stability. Binding of the complexes with calf thymus DNA (CT DNA) has been investigated by gel electrophoresis. The experimental results indicate that the complexes bind to DNA by intercalation mode and found to promote cleavage of plasmid pBR 322 DNA from the supercoiled form I to the open circular form II upon irradiation.     

Syntheses and Crystal Structures of Copper(II) and Copper(I) dpp Complexes, [Cu(dpp)Br2] and [Cu(dpp)2][CuBr2] (dpp = 2,9‐diphenyl‐1,10‐phenanthroline)

The complexes [Cu(dpp)Br₂] ( 1 ) and [Cu(dpp)₂][CuBr₂] ( 2 ) (dpp = 2,9‐diphenyl‐1,10‐phenanthroline) were synthesized and characterized by single‐crystal X‐ray diffraction methods. Reaction of copper(II) bromide with the dpp ligand in dichloromethane at room temperature afforded 1 , which is a rare example of non‐square planar four‐coordinate copper(II) complexes. Complex 1 crystallizes in the monoclinic space group C2/c with a = 15.352(3), b = 13.192(3), c = 11.358(2) Å, β = 120.61(3)°, V = 1979.6(7) ų, Z = 4, D_calc = 1.865 g cm^?3. The coordination geometry about the copper center is distorted about halfway between square planar and tetrahedral. The Cu‐N distance is 2.032(2) Å and the Cu‐Br distance 2.3521(5) Å. Heating a CH₂Cl₂ or acetone solution of 1 resulted in complex 2 , which consists of a slightly distorted tetrahedral [Cu(dpp)₂]⁺ cation and a linear two‐coordinate [CuBr₂]^? anion. 2 crystallizes in the triclinic space group with a = 10.445(2), b = 11.009(2), c = 18.458(4) Å, α = 104.72(3), β = 94.71(3), γ = 103.50(3)°, V = 1973.3(7) ų, Z = 2, D_calc = 1.602 g cm^?3. The four Cu(1)‐N distances are between 2.042(3) and 2.067(3) Å, the distance of Cu(2)‐Br(1) 2.2268(8) Å, and the disordered Cu(3)‐Br(2) distances are 2.139(7) and 2.237(4) Å, respectively. Complex 2 could also be prepared by directly reacting CuBr with dpp in CH₂Cl₂.     

Investigation of charge transfer and structural distortions during photo-inducted excitation of cuprous bis-2,9-dimethyl-1,10-phenanthroline complex by density functional theory

This work reported the investigation of the structural distortions and charge-transfer processes that occurred in the complex of cuprous(I) bis-2,9-dimethyl-1,10-phenanthroline upon oxidation to copper(II), , through a excited state of by density functional theory. The intramolecular electronic transfer from central metal-to-ligand (MLCT) upon the irradiation of light energy is confirmed. Due to this MLCT excitation, the structure of the excited state of is distorted and reorganized to adapt with the change of charge in central metal. As a result, the excited state of is formed, which has the similar electronic and structural properties with . The bulky substituents in 2- and 9-positions of the phenanthroline ligands can restrain the structural distort and decrease nonradiative decay rate. Thus, the electronic and steric effects of the ligands in the cuprous photo-sensitive complexes have important consequences in the behavior of their excited state.     

Bimetallic bis(diphenylphosphino)acetylene bridged copper(I) complexes with 1,10-phenanthroline derivatives: synthesis,crystal structure,and spectroscopic characterization

A new series of bimetallic bis(diphenylphosphino)acetylene-bridged copper(I) 1,10-phenanthroline complexes, [Cu₂(dppa)₂(L)₂](BF₄)₂; L?=?1,10-phenanthroline (1); 4-methyl-1,10-phenanthroline (2); 4,7-dimethyl-1,10-phenanthroline (3); and 2,9-dimethyl-1,10-phenanthroline (4), have been prepared and characterized by spectroscopic methods. The X-ray structures of 1 and 4 were determined. The structures consist of centrosymmetric bimetallic 10-membered chair-like dimetallacycles. In 1, intermolecular C–H?π interactions result in bending of the phenanthroline ligand and sterically induced lengthening of one Cu–P bond. In 1–4, the ³¹P NMR downfield coordination shift, relative to the free ligand, correlates with the basic strength of the 1,10-phenanthroline ligands.     

LIGAND-EXCHANGE REACTION BETWEEN TRIS(1,10-PHENANTHROLINE)METAL(II) AND TRIS(4,7-DIPHENYL-1,10-PHENANTHROLINE)METAL(II) IONS

Abstract

The ligand exchange reaction between [M(phen)₃]²⁺ and [M(DIP)₃]²⁺ (where M is the same and M = Fe^II or Ni^II, phen = 1,10-phenanthroline, DIP = 4,7-diphenyl-1,10-phenanthroline) has been investigated by reversed phase ion-paired chromatography (RP-IPC). The effect of pH and solvent on the ligand-exchange reaction is studied by monitoring the variation in chromatograms with time after mixing. The results have shown that the ligand exchange reaction between [M(phen)₃]²⁺ and [M(DIP)₃]²⁺ takes place in the pH range of 3–8 and the rate of reaction for nickel(II) complexes is about two times slower than that for iron(II) complexes. Experiments on the effect of various solvents on the ligand-exchange reaction have revealed that the rate of reaction is enhanced by the solvent in the following order: (CH₃)₂CO > CHCl₃ ≥ CH₂Cl₂ > CH₃CN > CH₃OH. Elemental analysis and UV-visible spectroscopy confirmed that the products obtained from the ligand-exchange reaction are mixed-ligand complexes containing phen and DIP ligands, i.e., [M(phen)₂(DIP)]²⁺ and [M(phen)(DIP)₂]²⁺.     

Syntheses and X-ray structures of heteroleptic octahedral Mn(II)-xanthato complexes involving N-donor ligands

A series of octahedral manganese(II) complexes involving xanthates and N-donor ligands, [Mn(S₂COiBu)₂(phen)] (1), [Mn(S₂COiBu)₂(2,2′-bpy)] (2), [Mn(S₂COnPr)₂(phen)] (3), [Mn(S₂COnPr)₂(2,2′-bpy)] (4), [Mn(S₂COMe)₂(2,2′-bpy)] (5), [Mn(S₂COnPr)₂(4,4′-bpy)]_n, and [Mn₂(S₂COnPr)₄(4,4′-bpy)₃] (6) (phen = 1,10-phenanthroline, bpy = bipyridine) was prepared. Complexes were characterized by elemental analysis, FTIR spectroscopy, TG/DSC analysis, and single-crystal X-ray diffraction. The structures are built of monomeric molecules of the complexes, except for 6 with the 4,4′-bipyridine ligand, which contains a binuclear complex and 1D polymeric zigzag chain in one crystal.     

Synthesis,crystallographic and spectroscopic characterization and magnetic properties of dimer and monomer ternary copper(II) complexes with sulfonamide derivatives and 1,10-phenanthroline. Nuclease activity by the oxidative mechanism

Three dinuclear and one mononuclear copper(II)-1,10-phenanthroline ternary complexes, [Cu(L1)(phen)(OH)]₂ (1), [Cu(L2)(phen)(OH)]₂·3H₂O (2), [Cu(L3)(phen)(OH)]₂ (3) and [Cu(L4)₂(phen)(H₂O)] (4), with thiadiazole sulfonamide derivative ligands: HL1 (N-(5-ethyl-1,3,4-thiadiazol-2-yl)naphthalene-1-sulfonamide), HL2 (N-(5-ethylthio)-1,3,4-thiadiazol-2-yl)-4-methylbenzenesulfonamide), HL3 (N-(5-ethyl-1,3,4-thiadiazol-2-yl)benzenesulfonamide) and HL4 (N-(5-ethyl-1,3,4-thiadiazol-2-yl)-4-methylbenzenesulfonamide) have been synthesized and characterized. In the four complexes each copper atom is five-coordinated. The structure of complexes 1, 2 and 3 consists of a dimeric unit with a C2 symmetry axis, where both coppers are bridged by two hydroxo anions. Magnetic measurements show that the dimer complexes are ferromagnetic according to the Cu–O–Cu angles. Cleavage experiments using pUC18 plasmid DNA in the presence of H₂O₂/ascorbic acid as an activating agent show that the title complexes are potent artificial chemical nucleases, the order of efficiency being 3 > 2 ∼ 1 > 4. Control cleavage experiments indicated that the dimer complexes are stronger artificial nucleases than the [Cu(phen)₂]²⁺ complex under the same experimental conditions, while the monomer 4 has a lower nuclease activity than the [Cu(phen)₂]²⁺ complex. The inhibition of the cleavage process in the presence of reactive oxygen intermediate scavengers suggests that the hydroxyl radical and the superoxide anion are reactive species for the breakage of the DNA strands.     

Supramolecular formation by aromatic ring stacking and hydrogen bonding in lanthanide(III) complexes with amino acids and 1,10-phenanthroline

[Eu(ABA)(phen)₂(H₂O)₃](ClO₄)₃·3phen·4.5H₂O (1) and [Eu(Val)(phen)₂(H₂O)₃](ClO₄)₃·3phen·2H₂O (2) are two new europium complexes with amino acids and 1,10-phenanthroline (phen=1,10-phenanthroline, ABA=-amino butyl acid, Val= -valine). Their crystal structures were measured by X-ray crystallography. Europium atoms in both complexes are nine-coordinated with bidentate 1,10-phenanthroline and carboxylate anion of amino acids, and water molecules. In the solid state, 1 and 2 have a structure involving aromatic stacking of the coordinated and non-coordinated 1,10-phenanthroline and the oxygen atoms of non-coordinated perchlorate anions being H-bond acceptors connect [Eu(ABA)(phen)₂(H₂O)₃]³⁺·3phen·4.5H₂O or [Eu(Val)(phen)₂(H₂O)₃]³⁺·3phen·2H₂O in their structures. In their interactions, several C–HO bonds play an important role. Owing to their different amino acid ligands and the number of lattice water molecules, there is some difference in their hydrogen bond patterns in 1 and 2. The side chain of -valine is involved in the formation of C–HO bonds. Hydrogen bond and π–π interactions determine the supramolecular formation of three-dimensional net works of both complexes.