A Tri‐µ‐O‐S‐O Manganese Dimer: Synthesis,Structral and EPR Study

A Tri‐µ‐O‐S‐O coordinative manganese dimer: [Mn₂(SO₄)₂(phen)₄]·CH₃OH (phen1,10‐phenanthroline) ( 1 ) was yielded by the reaction of 1,10‐phenanthroline and MnSO₄·H₂O in a mixed solvent of methanol and acetonitrile under room temperature and was structurally characterized. Single crystal analysis shows that complex 1 has polymeric structure based on binuclear Mn(II) units bridged by O‐S‐O groups of two SO₄²⁻ anion. The UV spectrum of the complex clarifies that each metal‐organic building unit parallels with each other through the Π‐Π interactions of face‐to‐face separations of two 1,10‐phen planes among the complex, forming a layered structure. And the electronic paramagnetic resonance (EPR) signal clearly indicates that those manganese atoms in complex 1 are in +2 oxidation states.     

A Sensitive Fluorescence Quenching Method for the Determination of Iron( Ⅱ） with 1,10-Phenanthroline

A sensitive and selective fluorescence quenching method for the determination of Fe²⁺ with 1,10‐phenanthroline was developed. The fluorescence intensity of 1,10‐phenanthroline at λ_ex of 266 run and λ_em of 365 nm was constant in the range of pH 4.0 to 10.0 and decreased linearly upon addition of Fe²⁺ to its solution. This decrease was mainly due to a static quenching effect caused by the formation of a non‐fluorescent complex of Fe²⁺ with 1, 10‐phenanthroline. The total amount of iron was determined by using hydroxylamine hydrochloride to reduce Fe³⁺ to Fe²⁺. The linear range was from 5.0 × 10–⁷ to 2.0 × 10–⁵ mol/L with a detection limit of 2.4 × 10–⁸ mol/L at 3s?. The quenching constant of Fe²⁺ to 1,10‐phenanthroline was calculated to be (5.70 × 0.05) × 10⁴ L/mol at 25 °C. Effects of foreign ions on the determination of Fe²⁺ were investigated. The results of the new method for the determination of iron in tap water and natural water samples were in good agreement with those obtained by graphite atomic absorption spectrometry.     

Bis(4,4′‐dimethyl‐2,2′‐bipyridine) ruthenium (II) Complexes Containing 2‐Arylimidazo‐ [4,5‐f] [1,10] phenanthroline: Syntheses,Characterization and Third‐order Nonlinear Optical Properties

Four novel mononuclear ruthenium(II) complexes [Ru(dmb)₂L]²⁺ [dmb = 4,4′‐dimethyl‐2,2′‐bipyridine, L = imidazo‐[4,5‐f][1,10]phenanthroline (IP), 2‐phenylimidazo‐[4,5‐f][1,10]phenanthroline (PIP), 2‐(4′‐hydroxyphenyl)imidazo‐[4,5‐f] [1,10] phenanthroline (HOP), 2‐(4′‐dimethylaminophenyl) imidazo‐[4, 5‐f] [1,10] phenanthroline (DMNP)] were synthesized and characterized by ES‐MS, ¹H NMR, UV‐vis and electrochemistry. The nonlinear optical properties of the ruthenium(II) complexes were investigated by Z‐scan techniques with 12 ns laser pulse at 540 nm, and all of them exhibit both nonlinear optical (NLO) absorption and self‐defocusing effect. The corresponding effective NLO susceptibility |x³| of the complexes is in the range of 2.68 × 10^?12‐4.57 × 10^?12 esu.     

(4‐Bromo‐2‐formyl­phenolato)­perchlorato­(1,10‐phenanthroline)­copper(II)

In the title copper(II) compound, [Cu(C₇H₄BrO₂)(ClO₄)(C₁₂H₈N₂)], the Cu atom is five‐coordinated in a distorted square‐pyramidal geometry by the N‐ and O‐donors of 4‐bromo‐2‐formyl­phenolate, 1,10‐phenanthroline and perchlorate. Pairs of complexes are linked together by Cu⋯O(phenolate) and π–π stacking inter­actions between 4‐bromo‐2‐formyl­phenolate and 1,10‐phenanthroline. Along the crystallographic a axis, the dimers are linked by hydrogen bonds between a perchlorate O atom and a 4‐bromo‐2‐formyl­phenolate H atom, and by further π–π stacking inter­actions. Hydrogen bonding between the Br atom and a 1,10‐phenanthroline H atom takes place between the stacks of dimers.     

Fabrication of Self‐Assembled Tris(1,10‐phenanthroline) ruthenium/12‐Molybdophosphoric Acid Films with Bifunctional Electrocatalytic and Photoluminescent Properties

The thin films containing transition metal complex tris(1,10‐phenanthroline) ruthenium(II) Ru(phen)₃Cl₂ (abbr Ru(phen)₃, phen=1,10‐phenanthroline), and 12‐molybdophosphoric acid [PMo₁₂O₄₀]_3? (abbr PMo₁₂) were fabricated on quartz, silicon and ITO substrates by layer‐by‐layer (LBL) method. The LBL films were characterized by the UV‐vis spectroscopy, X‐ray photoelectron spectroscopy, atomic force microscopy and cyclic voltammetry. The films can catalyze both the reduction of ClO , BrO , IO , and the oxidation of C₂O due to the presence of bifunctional composite, and the redox potentials depend on pH as a result of protonation. The photoluminescence of films were also investigated. The films exhibited photoluminescence arising from π*–t_2g ligand‐to‐metal transition of Ru(phen)₃.     

Aqua­bis(2‐nitro­benzoato‐κO)(1,10‐phenanthroline‐κ2N,N′)­zinc(II)

The title compound, [Zn(C₇H₄NO₄)₂(C₁₂H₈N₂)(H₂O)], has been synthesized. X‐Ray analysis reveals that it is a neutral zinc(II) mononuclear carboxyl­ate complex based on mixed N‐ and O‐donor ligands. The Zn atom is five‐coordinate in a distorted trigonal–bipyramidal coordination environment involving two O atoms of two monodentate 2‐nitro­benzoate mol­ecules, two N atoms of a 1,10‐phenanthroline mol­ecule and one O atom of a water mol­ecule. The axial positions are occupied by a carboxyl­ate O atom from the 2‐nitro­benzoate ligand and an N atom from the 1,10‐phenanthroline ligand [N—Zn—O = 167.66 (9)°].     

Tris(1,10‐phenanthroline‐κ2N,N′)iron(II) bis(2,4,5‐tricarboxybenzoate) monohydrate and tris(2,2′‐bipyridine‐κ2N,N′)iron(II) 2,5‐dicarboxybenzene‐1,4‐dicarboxylate–benzene‐1,2,4,5‐tetracarboxylic acid–water (1/1/2)

The title compounds, tris(1,10‐phenanthroline‐κ²N,N′)iron(II) bis(2,4,5‐tricarboxybenzoate) monohydrate, [Fe(C₁₂H₈N₂)₃](C₁₀H₅O₈)₂·H₂O, (I), and tris(2,2′‐bipyridine‐κ²N,N′)iron(II) 2,5‐dicarboxybenzene‐1,4‐dicarboxylate–benzene‐1,2,4,5‐tetracarboxylic acid–water (1/1/2), [Fe(C₁₀H₈N₂)₃](C₁₀H₄O₈)·C₁₀H₆O₈·2H₂O, (II), were obtained during an attempt to synthesize a mixed‐ligand complex of Fe^II with an N‐containing ligand and benzene‐1,2,4,5‐tetracarboxylic acid via a solvothermal reaction. In both mononuclear complexes, each Fe^II metal ion is six‐coordinated in a distorted octahedral manner by six N atoms from three chelating 1,10‐phenanthroline or 2,2′‐bipyridine ligands. In compound (I), the Fe^II atom lies on a twofold axis in the space group C2/c, whereas (II) crystallizes in the space group P2₁/n. In both compounds, the uncoordinated carboxylate anions and water molecules are linked by typical O—H...O hydrogen bonds, generating extensive three‐dimensional hydrogen‐bond networks which surround the cations.     

X‐ray and synchrotron diffraction studies of 2‐(pyridin‐2‐yl)‐1,10‐phenanthroline in the role of ligand for two copper polymorphs or hydrogen bonded with 2,2,6,6‐tetramethyl‐4‐oxopiperidinium hexafluorophosphate

Different extended packing motifs of dichlorido[2‐(pyridin‐2‐yl)‐1,10‐phenanthroline]copper(II), [CuCl₂(C₁₇H₁₁N₃)], are obtained, depending on the crystallization conditions. A triclinic form, (I), is obtained from dimethylformamide–diethyl ether or methanol, whereas crystallization from dimethylformamide–water yields a monoclinic form, (II). In each case, the Cu^II centre is in a five‐coordinate distorted square‐pyramidal geometry. The extended packing for both forms can be described as a highly offset π‐stacking arrangement, with interlayer distances of 3.674 (3) and 3.679 (3) Å for forms (I) and (II), respectively. The reaction of diprotonated Pt(tmpip₂NCN)Cl [tmpip₂NCN = 2,6‐bis(2,2,6,6‐tetramethylpiperidylmethyl)benzyl] with AgPF₆ under acidic conditions, followed by the addition of 2‐(pyridin‐2‐yl)‐1,10‐phenanthroline, results in a hydrogen‐bonded cocrystal, 2,2,6,6‐tetramethyl‐4‐oxopiperidinium hexafluorophosphate–2‐(pyridin‐2‐yl)‐1,10‐phenanthroline (1/1), C₉H₁₈NO⁺·PF₆⁻·C₁₇H₁₁N₃, (III). The extended packing maximizes π–π interactions in a parallel face‐to‐face arrangement, with an interlayer stacking distance of 3.4960 (14) Å.     

Tetra­aqua­(1,10‐phenanthroline‐κ2N,N′)cobalt(II) dinitrate: a hydrogen‐bonded supra­molecular network

The structure of the title compound, [Co(C₁₂H₈N₂)(H₂O)₄](NO₃)₂, consists of tetra­aqua­(1,10‐phenanthroline)cobalt(II) cations and nitrate anions. The Co atom is located on a twofold rotation axis and is coordinated by the two N atoms of a 1,10‐phenanthroline ligand and four O atoms of water mol­ecules. The cations and anions are linked by hydrogen‐bond inter­actions into a three‐dimensional supra­molecular network.     

Synthesis and Characterization of a Ruthenium(II) Complex for Photovoltaic Cells

We have designed and synthesized a new ruthenium complex, [(5‐amino‐1,10‐phenanthroline)bis(4,4′‐dicarboxylic acid‐2,2′‐bipyridine)]ruthenium(II) by introducing two types of ligands, 5‐amino‐1,10‐phenanthroline and 4,4′‐dicarboxylic acid‐2,2′‐bipyridine. We investigated the electronic, spectroscopic, electrochemical, and photovoltaic properties of the Ru(II) complex. The short‐circuit current density and overall solar‐to‐electric energy conversion efficiency of photovoltaic cells made with this Ru(II) complex were found to be 8.9 mA/cm² and 2.1%, respectively. A series of analogous Ru(II) complexes have also been synthesized and investigated to compare the effects of functional groups on various ligands. HOMO‐LUMO energies and molecular orbital surfaces have been investigated using semiempirical quantum chemical methods.     

Building [2]Catenanes around a Tris(diimine)ruthenium(2+) ([Ru(diimine)3]2+) Complex Core Used as Template

In the course of the last two decades, the use of transition metals as templates for constructing catenanes has almost exclusively been restricted to tetrahedral copper(I). The present work is dealing with an octahedral metal, ruthenium(II), coordinated to three bidentate chelates. Incorporation of two chelates (1,10‐phenanthroline) in a ring allows to prepare a C₂‐symmetric ruthenium complex, the two chelates being disposed cis to one another (see 14 ²⁺ and 16 ²⁺ in Scheme 5 and 6, resp.). The ring is large enough to accomodate a third chelate, thus allowing the metal‐directed threading of a long fragment containing the third chelate (2,2′‐bipyridine derivative; see 23 ²⁺ and 24 ²⁺ in Scheme 8). The last step consists of a ring‐closing metathesis reaction with two terminal olefins. The two ruthenium(II)‐complexed catenanes 25 ²⁺ and 26 ²⁺ were prepared by using this strategy, each containing a 42‐membered ring interlocked to a larger macrocycle (50‐ or 63‐membered ring) incorporating the two 1,10‐phenanthroline chelates. It is expected that these catenanes can be set in motion under light‐irradiation, thus behaving as photochemically driven molecular machines.     

Antibacterial,SOD mimic and nuclease activities of copper(II) complexes containing ofloxacin and neutral bidentate ligands

Drug‐based mixed‐ligand copper(II) complexes of type [Cu(OFL)(Aⁿ)Cl]·5H₂O (OFL = ofloxacin, A¹ = pyridine‐2‐carbaldehyde, A² = 2,2′‐bipyridylamine, A³ = thiophene‐2‐carbaldehyde, A⁴ = 2,9‐dimethyl‐1,10‐phenanthroline, A⁵ = 2,9‐dimethyl‐4,7‐diphenyl‐1,10‐phenanthroline, A⁶ = 4,5‐diazafluoren‐9‐one, A⁷ = 1,10‐phenanthroline‐5,6‐dione and A⁸ = 5‐nitro‐1,10‐phenanthroline) were synthesized and characterized. Spectral investigations of complexes revealed square pyramidal geometry. Viscosity measurement and absorption titration were employed to determine the mode of binding of complexes with DNA. DNA cleavage study showed better cleaving ability of the complexes compared with metal salt and standard drug by conversion of a supercoiled form of pUC19 DNA to linear via circular. From the SOD mimic study, concentration of complexes ranging from 0.415 to 1.305 µM is enough to inhibit the reduction rate of NBT by 50% (IC₅₀) in the NADH‐PMS system. Antibacterial activity was assayed against selective Gram‐negative and Gram‐positive microorganisms using the doubling dilution technique. Copyright © 2010 John Wiley & Sons, Ltd.     

A molybdenum complex with 4,7‐­diphenyl‐1,10‐phenanthroline

In the title compound, tetra­carbonyl­(4,7‐di­phenyl‐1,10‐phen­an­throline‐N,N′)­molyb­denum(0), [Mo(C₂₄H₁₆N₂)(CO)₄], the Mo‐atom coordination is distorted octahedral, with two CO groups cis to each other, but each trans to an N atom of the 4,7‐di­phenyl‐1,10‐phenanthroline (dpphen) ligand, and with the other two CO groups trans to each other and on the axis position. The complex has better solubility than [Mo(phen)(CO)₄], where phen is 1,10‐phenanthroline.     

An extended two‐dimensional copper–molybdate compound with mixed dicarboxyl and organodiamine ligands

The title complex, poly[di‐μ₃‐oxo‐hepta‐μ₂‐oxo‐tetra­oxo­bis(1,10‐phenanthroline)‐μ₄‐terephthalato‐dicopper(II)­tetra­molybdate(VI)], [Cu₂Mo₄(C₈H₄O₄)O₁₃(C₁₂H₈N₂)₂], represents a novel two‐dimensional copper–molybdate compound with mixed ligands. Tetra­nuclear molybdenum oxide clusters are joined through corner‐sharing into a ribbon‐like chain, with [Cu(phen)]²⁺ (phen is 1,10‐phenanthroline) complexes grafted onto either side. The terephthalate ligand lies about an inversion centre and links these chains to form a layer via Cu—O and Mo—O bonds. Face‐to‐face π–π stacking inter­actions between adjacent phen ligands stabilize the structure.     

Synthesis,Characterization and X‐ray Crystal Structure of a Chromium(III) Complex Obtained from a Proton‐Transfer Compound Containing 1,10‐Phenanthroline‐2,9‐dicarboxylic Acid and 2,6‐Pyridinediamine

The novel 1,10‐phenanthroline‐2,9‐dicarboxylate containing Chromium(III) complex, (pydaH)[Cr(phendc)₂] · 5H₂O, was synthesized using proton‐transfer compound LH₂, (pydaH₂)²⁺(phendc)^2?, (pyda: 2,6‐pyridinediamine; phendcH₂: 1,10‐phenanthroline‐2,9‐dicarboxylic acid) and thoroughly characterized by elemental analysis, IR spectroscopy, X‐ray crystallography and cyclic voltammetry. The complex crystallizes in the monoclinic space group P2₁/n with four formula units in the unit cell. The unit cell dimensions are: a = 13.962(3) Å, b = 14.529(3) Å, c = 16.381(3) Å and β = 106.691(4)°. In this complex, 1,10‐phenanthroline‐2,9‐dicarboxylate acts as a tridentate ligand and the lattice is composed of anionic hexacoordinated complex, [Cr(phendc)₂]^?, 2,6‐pyridiniumdiamine counter ion, (pydaH)⁺, and five lattice water molecules. Crystallographic characterization revealed that the resulting supramolecular structure is strongly stabilized by complicated network of hydrogen bonds between the crystallization water molecules, counter ion and both coordinated and uncoordinated carboxylate groups. There is no relevant π‐π interaction for this anionic complex between pyda or phendc moieties. The electrochemical studies indicated over potential for both the cathodic and anodic peaks of the complex with respect to the free Cr³⁺ ion, as a consequence of the energy requirement for rearrangement of the ligand at electrode surface.     

In‐house and synchrotron X‐ray diffraction studies of 2‐phenyl‐1,10‐phenanthroline,protonated salts,complexes with gold(III) and copper(II), and an orthometallation product with palladium(II)

Different salts of the 2‐phenyl‐1,10‐phenanthrolin‐1‐ium cation, (pnpH)⁺, are obtained by reacting 2‐phenyl‐1,10‐phenanthroline (pnp), C₁₈H₁₂N₂, (I), with a variety of anions, such as hexafluoridophosphate, C₁₈H₁₃N₂⁺·PF₆⁻, (II), trifluoromethanesulfonate, C₁₈H₁₃N₂⁺·CF₃SO₃⁻, (III), tetrachloridoaurate, (C₁₈H₁₃N₂)[AuCl₄], (IV), and bromide (as the dihydrate), C₁₈H₁₃N₂⁺·Br⁻·2H₂O, (V). Compound (I) crystallizes with Z′ = 2, with both independent molecules adopting a coplanar conformation. In (II)–(IV), a hydrogen bond exists between the cation and anion, while one of the lattice water molecules serves as a hydrogen‐bonded bridge between the cation and anion in (V). Reaction of (I) with HAuCl₄ gives the salt complex (IV); however, reaction with KAuCl₄ produces the monodentate complex trichlorido(2‐phenyl‐1,10‐phenanthroline‐κN¹⁰)gold(III), [AuCl₃(C₁₈H₁₂N₂)], (VI). Dichlorido(2‐phenyl‐1,10‐phenanthroline‐κ²N,N′)copper(II), [CuCl₂(C₁₈H₁₂N₂)], (VII), results from the reaction of CuCl₂·2H₂O and (I), in which the Cu^II center adopts a tetrahedrally distorted square‐planar geometry. The pendent phenyl ring twists to a bisecting position relative to the phenanthroline plane. The square‐planar Pd^II complex, bromido[2‐(phenanthrolin‐2‐yl)phenyl‐κ³C¹,N,N′]palladium(II), [PdBr(C₁₈H₁₁N₂)], (VIII), is obtained from the reaction of (I) with [PdCl₂(cycloocta‐1,5‐diene)], followed by addition of bromine. A coplanar geometry for the pendent ring is adopted as a result of the tridentate bonding motif.     

Luminescent Ruthenium(II) Polypyridyl Complexes as Nonviral Carriers for DNA Delivery

Two new luminescent ruthenium(II) polypyridyl complexes, [Ru(bpy)₂(tpt‐phen)]Cl₂ ( 1 ; bpy=2,2′‐bipyridine, tpt‐phen=triptycenyl‐1,10‐phenanthroline) and [Ru(phen)₂(tpt‐phen)]Cl₂ ( 2 ; phen=1,10‐phenanthroline), have been developed as potential nonviral vectors for DNA delivery. Photophysical and electrochemical properties of the complexes have been investigated and corroborated with electronic structure calculations. DNA condensation by these complexes has been investigated by UV/Vis and emission spectroscopy, circular dichroism spectroscopy, atomic force microscopy, dynamic light scattering, confocal microscopy, and electrophoretic mobility studies. These complexes interact with DNA and efficiently condense DNA into globular nanoparticles that are taken up efficiently by HeLa cells. DNA cleavage inability and biocompatibility of complexes have been explored. Both complexes have good gene transfection abilities.     

A New Polymer of Mixed‐Anions Complex [Pb(phen)(O2CCH3)(O2NO)]n (phen = 1,10‐phenanthroline)

The single crystal X‐ray data of a mixed anions complex of Pb^II with 1,10‐Phenantroline, [Pb(phen)(O₂CCH₃)‐ (O₂NO)], shows the complex to be polymeric as a result of acetate ligand bridging. The Pb atom has an asymmetrical eightfold coordination of two nitrogen atoms of the 1,10‐phenanthroline ligand and six oxygen atoms of the nitrate and acetate anions. The arrangement of the 1,10‐phenantroline ligand, acetate and nitrate anions suggest a gap in the coordination around the Pb^II ion, occupied possibly by a stereoactive lone pair of electrons on lead(II) where the coordination around the lead atoms is hemidirected. There is a π‐π stacking interaction between the parallel aromatic rings of an adjacent chain in the compound which might help to increase the ‘gap' in the coordination around the Pb^II ion.     

Bis­(acetato‐κ2O,O′)(2,9‐di­methyl‐1,10‐phenanthroline‐κ2N,N′)mercury(II) in two differently hydrated crystal forms

Two differently hydrated crystal forms of the title compound, viz. bis­(acetato‐κ²O,O′)(2,9‐di­methyl‐1,10‐phenanthroline‐κ²N,N′)­mercury(II), [Hg(C₂H₃O₂)₂(C₁₄H₁₂N₂)] or [HgAc₂(dmph)] [dmph is 2,3‐di­methyl‐1,10‐phenantroline (neocuproine) and Ac is acetate], (I), and tris­[bis­(acetato‐κ²O,O′)(2,9‐di­methyl‐1,10‐phenanthroline‐κ²N,N′)­mercury(II)] hexadecahydrate, [Hg(C₂H₃O₂)₂(C₁₄H₁₂N₂)]₃·16H₂O or [HgAc₂(dmph)]₃·16H₂O, (II), are presented. Both structures are composed of very simple monomeric units, which act as the building blocks of complex packing schemes stabilized by a diversity of π–π and hydrogen‐bonding interactions.     

Tetra­aqua(3,4,7,8‐tetra­methyl‐1,10‐phenanthroline‐κ2N,N′)­zinc(II) thio­sulfate

In the title complex of zinc(II) with 3,4,7,8‐tetra­methyl‐1,10‐phenanthroline (tmph), viz. [Zn(C₁₆H₁₆N₂)(H₂O)₄](S₂O₃), the metal atom has a monomeric octahedral ZnN₂O₄ complex environment comprising two N‐atom donors from the tmph group and four aqua O‐atom donors. The complex cation is connected to four thio­sulfate anions through a compact hydrogen‐bonding network involving all coordinated aqua H‐atom donors and all the outer acceptors (O and S) of the anion.