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Phenanthroline
Terms modified by Phenanthroline Selected AbstractsSynthesis of New Phenanthroline-Based Heteroditopic Ligands , Highly Efficient and Selective Fluorescence Sensors for Copper(II) IonsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 21 2006Peter Comba Abstract The heteroditopic phenanthroline derivatives 5,6-bis(2-pyridylcarboxamido)-1,10-phenanthroline (H2L1) and 5,6-bis[(4-methoxy-2-pyridyl)carboxamido]-1,10-phenanthroline (H2L2) have been prepared and characterized, together with their luminescent ruthenium(II) complexes [Ru(bpy)2(H2L1,2)](PF6)2 and [Ru(H2L1)3](PF6)2 and the corresponding iron(II) complex [Fe(H2L1)3](PF6)2. In these complexes, the metal ion is coordinated by the bidentate phen site of H2L. The luminescence of the ruthenium complexes (,ex = 450 nm, ,em ca. 620 nm) is completely quenched by Cu2+ ions in the micromolar concentration range and, to a lesser extent, by other metal ions. At pH 5, the response of the luminescent sensors is highly Cu2+ -selective. Heterodinuclear complexes [Ru(bpy)2(LM)](PF6)2, [Ru(LM)3](PF6)2, and [Fe(LM)3](PF6)2 have been isolated for M = Cu2+, Ni2+, Co2+, and Pd2+. It is suggested that M is coordinated to the tetradentate N4 site of L by two deprotonated amide N atoms and two pyridyl groups. This coordination type is confirmed by the EPR spectrum of the compound [RuII(bpy)2(L1CuII)](PF6)2.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Tetracyanoquinodimethanido Derivatives of (Terpyridine)- and (Phenanthroline)metal Complexes , Structural and Magnetic Studies of Radical-Ion SaltsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 3 2005Cristina Alonso Abstract Several derivatives of formulae [M(terpy)2](TCNQ)2 or [M(terpy)2](TCNQ)3 (M = Ni, Cu, Zn; terpy = 2,2,:6,,2"-terpyridine; TCNQ= 7,7,8,8-tetracyanoquinodimethane) and [M(phen)3](TCNQ)2 or [M(phen)3](TCNQ)4 (M = Fe, Ni; phen = 1,10-phenanthroline) have been obtained. The crystal structures of [M(terpy)2](TCNQ)2 (M = Ni, Cu) show that the metal is surrounded by the terpyridine nitrogen atoms in a closed octahedral environment and the TCNQ anions are dimerised by , overlap. The cationic [M(terpy)2]2+ and the anionic [TCNQ]22, groups alternate in the crystal. For the derivatives with three TCNQ groups, the existence of a stack of trimeric [TCNQ]32, ions having electronic delocalisation is proposed. The compound [Fe(phen)3](TCNQ)2, which shows a strong interaction between TCNQ anions, led to the formation of a , bond in the diamagnetic species [TCNQ,TCNQ], while the nickel analogue is expected to have a localised structure formed by alternation of cationic metal complexes and dimeric [TCNQ]22, anions similar to those observed in the analogous terpy derivatives. The derivatives having four TCNQ groups also show electronic delocalisation and a 1D stack based on the magnetic data is proposed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] First Examples of Ternary Lanthanide 2,2,-Diphenyldicarboxylate Complexes: Hydrothermal Syntheses and Structures of Lanthanide Coordination Polymers of 2,2,-Diphenyldicarboxylic Acid and 1,10-PhenanthrolineEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2003Yibo Wang Abstract In the four new lanthanide coordination polymers {[La2(2,2,-dpdc)3(phen)(H2O)]·2H2O}n (1), [Eu2(2,2,-dpdc)3(phen)(H2O)2]n (2), {[Ln2(2,2,-dpdc)3(phen)2(H2O)2]·4H2O}n [Ln = Tb (3), Yb (4)] (2,2,-dpdc = 2,2,-diphenyldicarboxylate, phen = 1,10-phenanthroline), prepared by hydrothermal synthesis, the 2,2,-dpdc dianion affords tetradentate, pentadentate, and hexadentate coordination modes. Complex 1 is a two-dimensional network of infinite 1-D chains assembled through ,,, interactions, with nine- and ten-coordinate La3+, and arranged in wave-like layers. In 2, Eu3+ possesses nine- and ten-coordinate geometries bridged by 2,2,-dpdc ligands to give a 3-D structure. The isomorphous complexes 3 and 4, in which Tb3+ and Yb3+ ions are both nine-coordinate, have two-dimensional structures of 1-D zigzag chains stacked via hydrogen bonds and ,,, interactions of phen molecules. The high-resolution emission spectrum of 2 shows two Eu3+ ion sites, which is consistent with the results of the X-ray crystal structure analysis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] New Ruthenium Complexes Containing Oligoalkylthiophene-Substituted 1,10-Phenanthroline for Nanocrystalline Dye-Sensitized Solar Cells,ADVANCED FUNCTIONAL MATERIALS, Issue 1 2007C.-Y. Chen Abstract Two new ruthenium complexes [Ru(dcbpy)(L)(NCS)2], where dcbpy is 4,4,-dicarboxylic acid-2,2,-bipyridine and L is 3,8-bis(4-octylthiophen-2-yl)-1,10-phenanthroline (CYC-P1) or 3,8-bis(4-octyl-5-(4-octylthiophen-2-yl)thiophen-2-yl)-1,10-phenanthroline (CYC-P2), are synthesized, characterized by physicochemical and semiempirical computational methods, and used as photosensitizers in nanocrystalline dye-sensitized solar cells. It was found that the difference in light-harvesting ability between CYC-P1 and CYC-P2 is associated mainly with the location of the frontier orbitals, in particular the highest occupied molecular orbital (HOMO). Increasing the conjugation length of the ancillary ligand decreases the energy of the metal-to-ligand charge transfer (MLCT) transition, but at the same time reduces the molar absorption coefficient, owing to the HOMO located partially on the ancillary ligand of the ruthenium complex. The incident photon-to-current conversion efficiency curves of the devices are consistent with the MLCT band of the complexes. Therefore, the overall efficiencies of CYC-P1 and CYC-P2 sensitized cells are 6.01 and 3.42,%, respectively, compared to a cis- di(thiocyanato)-bis(2,2,-bipyridyl)-4,4,-dicarboxylate ruthenium(II)-sensitized device, which is 7.70,% using the same device-fabrication process and measuring parameters. [source] Binding Studies of Asymmetric Pentacoordinate Copper(II) Complexes Containing Phenanthroline and Ethane-1,2-diamine Ligands with Calf-Thymus DNAHELVETICA CHIMICA ACTA, Issue 9 2005Farukh Arjmand New chiral complexes of the composition [MLL,], where HL=1,2-bis(1H -benzimidazol-2-yl)ethane-1,2-diol=H2bimedol, M=CoII, NiII, CuII, and L,=1,10-phenanthroline (phen) or ethane-1,2-diamine (en), were synthesized and characterized. The ligand L exhibited a coordination mode involving the O-atom of only one OH group, the other one being directed away from the metal center. The complexes [Cu(Hbimedol)(en)]Cl (1), [Cu(Hbimedol)(phen)]Cl (2), [Co(Hbimedol)(phen)]Cl (3), [Ni(Hbimedol)(en)]Cl (4), and [Ni(Hbimedol)(phen)]Cl (5) were ionic in nature and stable at room temperature. The donor sets involved in coordination with the metal ions were the O-atom of one OH group and two N-atoms of the two benzimidazole moieties, besides the two N-atoms of phen or en (Fig.,1.). The proposed five-coordinate geometry of 1,5 was established by analysis of spectroscopic data; the ball-and-stick models supported the proposed structures of 1,5 since they showed apparently no strain on any bond and angle. The interaction of complexes 1 and 2 with calf-thymus DNA were carried out by UV/VIS titration, circular dichroism, electrochemical methods, and viscometry. The intrinsic binding constant Kb of 1 and 2 was determined as 1.57,104 and 1.51,104,M,1, respectively, suggesting that both complexes bind strongly to calf-thymus DNA. [source] Remarkable Stabilization of Duplex DNA Containing an Abasic Site by Non-Nucleosidic Phenanthroline and Pyrene Building BlocksCHEMBIOCHEM, Issue 5 2005Simon M. Langenegger Dipl.-Chem. Filling the gap. Abasic sites represent a frequently occurring lesion in DNA. If not repaired, such lesions can lead to mutations or cell death. Stabilization of DNA containing abasic sites is investigated as a therapeutic approach for the treatment of cancer. Non-nucleosidic phenanthroline and pyrene derivatives were found to have a profound stabilizing effect (,Tm=8,°C) on DNA missing a nucleobase. [source] ChemInform Abstract: Two Novel Copper,Undecaniobates Decorated by Copper,Organic Cations [{Cu(H2O) L}2{CuNb11O35H4}]5- (L: 10-Phenanthroline, 2,2,-Bipyridine) Consisting of Plenary and Monolacunary Lindqvist-Type Isopolyniobate Fragments.CHEMINFORM, Issue 40 2010Jing-Yang Niu Abstract Compounds (III) and (IV) represent the first examples of copper undecaniobates. [source] ChemInform Abstract: Enantioselective Synthesis of a Novel Chiral 2,9-Disubstituted 1,10-Phenanthroline and First Applications in Asymmetric Catalysis.CHEMINFORM, Issue 18 2010Mecheril Valsan Nandakumar Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Samarium-Promoted Coupling of 1,10-Phenanthroline with Carbonyl Compounds for Synthesis of New Ligands.CHEMINFORM, Issue 33 2004Jeremy A. Weitgenant Abstract For Abstract see ChemInform Abstract in Full Text. [source] Highly Effective Recognition of Carbohydrates by Phenanthroline-Based Receptors: ,- versus ,-Anomer Binding PreferenceCHEMISTRY - A EUROPEAN JOURNAL, Issue 48 2009Monika Mazik Prof. No abstract is available for this article. [source] Synthesis and Thermal Decomposition Kinetics of the Complex of Samarium p -Methylbenzoate with 1,10-PhenanthrolineCHINESE JOURNAL OF CHEMISTRY, Issue 1 2007Jian-Jun Zhang Abstract The complex [Sm(p -MBA)3phen]2 (p -MBA, p -methylbenzoate; phen, 1,10-phenanthroline) was prepared and characterized by elemental analysis, IR and UV spectra. The thermal decomposition process of [Sm(p - MBA)3phen]2 was studied under a static air atmosphere by TG-DTG and IR techniques. Thermal decomposition kinetics was investigated employing a newly proposed method, together with the integral isoconversional non-linear method. Meanwhile, the thermodynamic parameters (,H,, ,G, and ,S,) were also calculated. The lifetime equation at mass-loss of 10% was deduced as ln ,=,24.7825+18070.43/T by isothermal thermogravimetric analysis. [source] Secondary Synthesis of Two Cobalt Complexes by the Use of 5-Sulfosalicylate and 1,10-Phenanthroline and Their Crystal StructuresCHINESE JOURNAL OF CHEMISTRY, Issue 10 2005Sai-Rong Fan Abstract Cobalt(II) nitrate reacted with 1,10-phenanthroline (phen) and 5-sulfosalicylic acid (H3ssal) to yield the cobalt(II) complex [Co(phen)2(H2O)2](Hssal)·4H2O (1) and the reaction of 1 with copper acetate led to a novel complex [Co(phen)(H2O)4][Cu2(ssal)2(phen)2]·5H2O (2). These two complexes were cation-anion species and the cationic motif [Co(phen)2(H2O)2]2+of 1 could be converted to [Co(phen)(H2O)4]2+ in the formation process of new anion [Cu2(phen)2(ssal)2]2, of 2. In both complexes abundant hydrogen bonds construct different supramolecular architectures, thus the conversion reaction can provide a new path to create novel supramolecular network. [source] Synthesis and Structures of Lanthanide Complexes of N - p -Tolylsulfonylglycinate and 1,10-PhenanthrolineCHINESE JOURNAL OF CHEMISTRY, Issue 9 2005Man-Bo Zhang Abstract Three new lanthanide complexes with the formulae [Eu2(TsGly) 6(phen) 2(H2O) 2] (1), [Ln(TsGly) 2(phen) 2(H2O) 2]Cl·2H2O [Ln=Er (2a) and Yb (2b), TsGlyN - p -tolylsulfonylglycinate, phen1,10-phenanthroline] were synthesized. Crystallographic data for 1: monoclinic, P21/n, a=1.29791(16) nm, b&=1.9034(2) nm, c=1.7596(2) nm, ,=93.410(3) °, V=4.3394(9) nm3, Z=4, R1=0.0326, wR2=0.0771; and for 2b: triclinic, P1, a=1.2674(2) nm, b=1.4405(2) nm, c=1.4809(3) nm, ,=113.256(3) °, ,=108.253(3) °, ,=94.739(3) °, V=2.2922(7) nm3, Z2,R1=0.0292, w R2=0.0669. X-ray diffractional analysis reveals that compound 1 adopts dinuclear structure with fourfold bridging TsGly ligands between the Eu(III) centers, while compound 2b features an unusual mononuclear structure. [source] Synthesis and crystal structure of [CuCl(phen)2]3H3V10O28 · 7 H2OCRYSTAL RESEARCH AND TECHNOLOGY, Issue 7 2005E. Rakovský Abstract The new compound, [CuCl(phen)2]3H3V10O28 · 7 H2O, was prepared by reaction of an aqueous KVO3 solution (pH 3) with an aqueous solution of CuSO4 · 5 H2O in which 1,10-phenanthroline (phen) and KCl were added. The crystal structure of the compound was determined, and the proton position in H3V10O283, were calculated by the bond length/bond number method and also determined from difference electron density map. The protons are bound to colinearly arranged ,,OV2 and ,,OV3 groups which is the common protonation type in trihydrogen decavanadates. The structure crystallizes in P1 space group symmetry. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Electrochemically Induced Iron Release of Adsorbed Horse Spleen Ferritin: Quantitation of Iron Using Long Optical Path Length Thin-Layer SpectroelectrochemistryELECTROANALYSIS, Issue 23 2007Abstract In this work, long optical path length thin-layer electrochemical cell was constructed using indium-tin oxide on glass as the electrode material. Iron release from ferritin adsorbed on the electrode was induced by applying a negative potential sweep in the presence of 1,10-phenanthroline. The usefulness of spectroelectrochemistry as a means of determining the quantity of iron released from an adsorbed layer of ferritin is demonstrated. [source] Analysis of sub-ppb levels of Fe(II), Co(II), and Ni(II) by electrokinetic supercharging preconcentration, CZE separation, and in-capillary derivatizationELECTROPHORESIS, Issue 20 2007Marek Urbanek Abstract The analysis of sub-ppb levels of Fe(II), Co(II), and Ni(II) in heat exchanger fluids of nuclear power plants is needed to monitor corrosion. A method involving preconcentration with electrokinetic supercharging (electrokinetic injection with transient ITP), CZE separation, and in-capillary derivatization with ortho -phenanthroline (o -Phe) for direct UV detection was thus developed. First, a multizone BGE was loaded into the capillary by successive hydrodynamic introduction of zones of (i) o -Phe-containing BGE, (ii) BGE for the zonal separation, and (iii) ammonium-based leading electrolyte. Metal cations were electrokinetically injected and stacked at the capillary inlet behind this last leading zone. Finally, a terminating electrolyte zone was hydrodynamically introduced. When a constant voltage was applied, metal ions kept on concentrating isotachophoretically, then separated in CZE mode, were complexed by migrating through an o -Phe zone, and finally detected by direct absorbance. To detect extremely thin peaks, it was attempted for the first time to focus the derivatization reagent by inducing a second transient ITP, before labeling analytes, already separated in CZE mode. With this arrangement, LODs were about 30,ppt in pure water. In heat exchanger fluid matrices containing 1000,ppm bore and 2,ppm lithium, only Fe(II) cation was detected among the three cations of interest at the 1,ppb level using the present method, and its LOD was about ten times higher, due to the lower loading rate during electrokinetic injection. [source] Magneto,Structural Correlations in Discrete MnII -WV Cyano-Bridged Assemblies with Polyimine LigandsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 26 2010Robert Podgajny Abstract We present the magneto,structural correlations for two novel discrete cyano-bridged assemblies based on cationic complexes of manganese(II) with diimine ligands and octacyanotungstate(V) ions. The crystal structure of [MnII(terpy)(dmf)(H2O)2][MnII(terpy)(H2O)(dmf)(,-NC)WV(CN)7]2·6H2O (1) (terpy = 2,2,;6,,2,-terpyridine, dmf = dimethylformamide) contains dinuclear {MnIIWV}, cyano-bridged anions, while the crystal structure of [MnII(phen)3]2[MnII(phen)2(,-NC)2WV(CN)6]2(ClO4)2·9H2O (2) (phen = 1,10-phenanthroline) is built of tetranuclear {MnII2WV2}2, square anions. Intramolecular Mn,W magnetic interactions through the cyano bridges are represented by magnetic coupling constants J = ,39 cm,1 for the {MnIIWV}, unit in 1 and J1 = ,25.7 and J2 = ,16.7 cm,1 for the {MnII2WV2}2, unit in 2. J and J1 represent relatively strong W,CN,Mn interactions and are ascribed to the bridges in b positions of TPRS-8 (trigonal prism square-face bicapped) of [W(CN)8]3, polyhedra, favoring the strongest electronic interactions between the d,d orbital of W and the ,* orbitals of CN,, whereas J2 is related to the m vertex of [W(CN)8]3,. The magnetic properties of 1 and 2 are compared with reference compounds and discussed in the context of the type of coordination polyhedra of [W(CN)8]3, as well as the metric parameters of cyano-bridged W,CN,Mn linkages. We found the type of coordination polyhedra and bridging mode of [W(CN)8]3, to be the most important factors influencing the magnitude of the Mn,W magnetic interaction. [source] New Approaches to 12-Coordination: Structural Consequences of Steric Stress, Lanthanoid Contraction and Hydrogen BondingEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 18 2010Anthony S. R. Chesman Abstract The anionic dinitrile ligand dicyanonitrosomethanide (dcnm), C(CN)2(NO),, and the anion resulting from its addition product with water, carbamoylcyanonitrosomethanide (ccnm), C(CN)(CONH2)(NO),, have been incorporated into lanthanoid complexes and display unusual ,2(N,O) nitroso coordination modes. (Et4N)3[Ln(ccnm)6] (1Ln; 1Ln = 1La, 1Ce, 1Pr, 1Nd, 1Sm) and (Me4N)3[Ln(ccnm)6] (2Ln; 2Ln = 2La, 2Ce, 2Pr, 2Nd) are systems containing 12-coordinate homoleptic trianionic lanthanoidate complexes. The nitroso groups of the ccnm ligands form three-membered ring chelates with the lanthanoid metal centre, with the asymmetry of the nitroso ,2 interactions dependent upon the intramolecular N,H···O=N hydrogen bonding. Additional intermolecular hydrogen bonding interactions exist between adjacent amide and nitrile groups giving rise to 3D ,-Po and 6,8-connected (412.63)(420.68) networks in 1Ln and 2Ln, respectively. The compounds (Me4N)3[Ln(dcnm)6] (3Ln; 3Ln = 3La, 3Ce, 3Nd, 3Sm) also contain a 12-coordinate trianionic lanthanoidate complex with the nitroso group exhibiting a highly symmetrical ,2 interaction. The sterically crowded environments of [Ln(18-crown-6)(dcnm)3] (4Ln; 4Ln = 4La, 4Ce, 4Pr, 4Nd) result in a shift towards a more asymmetric ,2 bonding of the nitroso group with decrease in the Ln3+ radius. There is a corresponding increase of the Ln,O,N angle, and one ligand is ,1(O) binding in 4Nd. The dcnm ligands in the discrete complexes [La(phen)3(dcnm)(3,x)Clx], x , 0.25 (5) (phen = 1,10-phenanthroline), (Et4N)[Ce(phen)2(dcnm)4] (6a/b, 6c) and [Ce(phen)2(dcnm)Cl2H2O] (7) display a variety of coordination modes. Complex 5 has 1D chains formed by ,,, stacking of adjacent phen co-ligands. Complexes 6 contain the monoanionic complex [Ce(phen)2(dcnm)4], with two geometric isomers present in the crystal structure of 6a/b. Complex 7 forms extended 1D chains via hydrogen bonding between coordinated water and chloride atoms and an extensive array of face-to-face , interactions. [source] Studies in Solution and the Solid State of Coordination Compounds Derived from LiBH4, NaBH4, and Bidentate Aromatic AminesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2010Milagros Aguilar-Martínez Abstract The mixture of 2,2,-bipyridylamine, 2,2,-bipyridine, 1,10-phenanthroline, 1,2-phenylendiamine, and 1,4-phenylendiamine each with LiBH4 and NaBH4 in a 1:1 molar ratio in THF yields seven new complexes of the type MBH4·L-THF and one complex of the type MBH4·L. These compounds were characterized by IR and NMR spectroscopy and X-ray single-crystal structure determinations. In the solid state, the [BH4], group is bidentate, as deduced from the stretching patterns observed in IR spectra and confirmed by X-ray single-crystal structure analysis. NMR spectroscopy showed that all amines act as bidentate ligands and are symmetrically coordinated to the metal cation. Complexes LiBH4 -2,2,-bipyridine-THF (1), NaBH4 -2,2,-bipyridine-THF (2), LiBH4 -1,10-phenanthroline-THF (3), and NaBH4 -1,10-phenanthroline-THF (4) have a discrete molecular structure, whereas the complexes LiBH4 -1,2-phenylendiamine-THF (5), NaBH4 -1,2-phenylendiamine-THF (6), LiBH4 -2,2,-dipyridilamine (7), and LiBH4 -1,4-phenylendiamine-THF (8) have polymeric structures in the solid state. N -borane-dipyridylamine adduct 9 was isolated from an aged solution of 7. IR spectroscopy of the new complexes showed that the structures of complexes 1, 3, 4, and 6 are maintained in the solid state and in solution. A rotational barrier for the [BH4], group of less than 38 KJ,mol,1 was estimated for some of the new complexes. [source] Self-Assembly from Discrete Clusters to 2D Network Based on [Fe(phen)(CN)4], and [Fe(bipy)(CN)4],: Synthesis, Structures and Magnetic PropertiesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 14 2009Hua Xiang Abstract A series of cyanido-bridged complexes {[FeIII(phen) (CN)4]2[NiL1]}·4H2O (1), {[FeIII(bipy)(CN)4]2[NiL1]}·4H2O (2), [FeIII(bipy)(CN)4]2[NiL2] (3), {[FeIII(phen)(CN)4]2[CuL3]}·5H2O (4), {[FeII(phen)(CN)4][Ni(ea)2]}2·2H2O (5), {[FeII(phen)(CN)4] [NiL2]·2H2O}n (6), {[FeIII(bipy)(CN)4]2[Ni(H2O)2]}·6.5H2O}n (7) and {[FeII(bipy)(CN)4][Ni(ea)2]·H2O}n (8) were synthesized using H[Fe(phen)(CN)4]·2H2O and H[Fe(bipy)(CN)4]·2H2O as precursors [L1 = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, L2 = 3,10-bis(2-phenylethyl)-1,3,5,8, 10,12-hexaazacyclotetradecane, L3 = 3,10-bis(2-hydroxyethyl)-1,3,5,8,10,12-hexaazacyclotetradecane, phen = 1,10-phenanthroline, bipy = 2,2,-bipyridine, ea = ethanolamine). Complexes 1,4 are trinuclear clusters, and 5 is a tetranuclear square. In 6, the [FeII(phen)(CN)4]2, anions alternately bridge the [NiL2]2+ cations to generate a 1D wavy chain. The structure of 7 possesses a 4,2-ribbonlike chain, which contains a NiII2(CN)4FeIII2 square with each NiII atom shared by two adjacent squares. Each FeII and NiII atom in 8 acts as a three-connected node through the cyanido-bridges to generate a 2D network with a 4,82 topological net. Ferromagnetic couplings are found between the low-spin FeIII ions and the NiII ions through the cyanido groups in 1,3 and 7, and a metamagnetic behavior and a frequency dependence of the out-of-phase ac susceptibility are observed in 7. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Oligonucleotide Duplexes with Tethered Photoreactive Ruthenium(II) Complexes: Influence of the Ligands and Their Linker on the Photoinduced Electron Transfer and Crosslinking Processes of the Two StrandsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 4 2009Stéphanie Deroo Abstract The photoreactivity of new RuII -oligonucleotide conjugates is investigated in the presence of their complementary strands. The goal is to determine the origins of different effects of parameters that control the photocrosslinking process of the two strands. Therefore, two RuII compounds, either [Ru(tap)3]2+or [Ru(tap)2phen]2+ (tap = 1,4,5,8-tetraazaphenanthrene, phen = 1,10-phenanthroline) with different oxidation powers, were tethered with different linkers to either the 5,- or 3,-phosphate end of the probe strand before hybridization with the complementary strand. These systems were studied by time-resolved emission spectroscopy, UV/Vis absorption experiments, PAGE and MS (ESI) analyses. The best yields of photocrosslinking (45,%) obtained with [Ru(tap)3]2+ tethered to the 3,-position are due to (i) a higher oxidation power of the complex and (ii) its attachment at the 3,-position. Indeed, this tethering favours the interaction of the Ru compound with the duplex and, therefore, inhibits its photodechelation. This work allows better design of sequence-specific DNA photodamaging agents prior to biological applications.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Synthesis, Structural, Thermal and Magnetic Characterization of a Pyrophosphato-Bridged Cobalt(II) ComplexEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 17 2008Oluwatayo F. Ikotun Abstract The reaction in water of CoII sulfate heptahydrate with 1,10-phenanthroline (phen) and sodium pyrophosphate (Na4P2O7) in a 2:4:1 stoichiometric ratio resulted in the crystallization of a neutral dinuclear CoII complex, {[Co(phen)2]2(,-P2O7)}·6MeOH (1), as revealed by a single-crystal X-ray diffraction study. The bridging pyrophosphato ligand between the two [Co(phen)2]2+ units in a bis(bidentate) coordination mode places the adjacent metal centers at 4.857 Å distance, and its conformation gives rise to intramolecular ,,, stacking interaction between adjacent phen ligands. Indeed, intermolecular ,,, stacking interactions between phen ligands from adjacent dinuclear complexes create a supramolecular 2D network in 1. Magnetic susceptibility measurements on a polycrystalline sample of 1 in the temperature range 1.9,295 K are typical of an overall antiferromagnetic coupling with a maximum of the magnetic susceptibility at 3.0 K. The analysis of the magnetic data in the whole temperature range allows the determination of the value of the intramolecular magnetic coupling (J = ,1.23 cm,1). The ability of the pyrophosphato ligand to mediate magnetic interactions between different first-row transition-metal ions when adopting the bis(bidentate) bridging mode is analyzed and discussed in the light of the small number of magneto-structural reports on this type of compound, bearing in mind the number of unpaired electrons and type of magnetic orbitals on each metal center. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Synthesis, Structure and Magnetic Behaviour of Manganese(II) Selenolate Complexes ,1[Mn(SePh)2], [Mn(SePh)2(bipy)2] and [Mn(SePh)2(phen)2] (bipy = bipyridyl, phen = phenanthroline)EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 30 2007Andreas Eichhöfer Abstract The manganese selenolate complex ,1[Mn(SePh)2] has been prepared by reaction of Mn(OOCCH3)2 with 2 equiv.PhSeSiMe3 in thf. In the crystal structure, the compound forms one-dimensional chains, and the bridging selenolate ligands result in relatively short metal,metal contacts of about 3 Å. Reaction with two equivalents of the Lewis bases 2,2,-bipyridine and 1,10-phenanthroline yielded the monomeric octahedral complexes [Mn(SePh)2(2,2,-bipy)2] and [Mn(SePh)2(1,10-phen)2], respectively. The magnetic and optical properties of these complexes have been investigated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Crystal Structure and Surface Photovoltage Properties of MnII Coordination SupramoleculesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2007Li-Ping Sun Abstract Three MnII coordination supramolecular complexes [Mn(pdc)(H2O)]n1, {[Mn(pdc) (phen)(H2O)]·3H2O}n2, and {[Mn(cyan)2(H2O)4]·2HCl·2(Hcyan)} 3 (H2pdc = pyridine-2,3-dicarboxylic acid, Hcyan = cyanuric acid, phen = 1,10-phenanthroline) were hydrothermally synthesized and their structures determined by single-crystal X-ray diffraction. The pdc group in complex 1 bridges the MnII ions to form an infinite 3D structure. In complex 2, the MnII ion is bridged to a 1D infinite chain by pdc groups and the chain is further connected to a 2D structure by hydrogen bonds. The 3D structure of complex 3 is formed by hydrogen bonds and O···Cl weak interactions. Surface photovoltage spectroscopy (SPS) of complexes 1,3 indicate that they all possess positive SPV response in the range of 300,800 nm and show p -type semiconductor characteristic. The intensities of the SPV responses are obviously different, and this can mainly be attributed to the differences in their structures. Field-induced surface photovoltage spectroscopy (FISPS) of complexes 1,3 confirms their p -type semiconductor characteristic.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Three Novel Functional CdII Dicarboxylates with Nanometer Channels: Hydrothermal Synthesis, Crystal Structures, and Luminescence PropertiesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 2 2007Yu-Peng Tian Abstract Three novel functional transition-metal complexes with H2A (H2A = 9-ethylcarbazole-3,6-dicarboxylic acid), Cd(HA)2(H2O)2 (1), [Cd(A)(phen)]·1.5H2O (2) (phen = 1,10-phenanthroline), and Cd(HA)2(bipy) (3) (bipy = 4,4,-bipyridine), have been successfully synthesized by a hydrothermal synthetic method and characterized by single-crystal X-ray diffraction, infrared spectroscopy, elemental analysis, thermogravimetric analysis, and photoluminescence. The results show that all of the complexes contain nanometer channels, while the coordination modes were changed by the addition of the mixed ligands. The 2D supramolecular open-framework 1 is constructed through hydrogen-bond and aromatic ,,, interactions. 2D coordination polymer 2 is constructed by ,,, interactions between adjacent metal-organic polymeric coordination chains. Interestingly, the 3D supramolecular architecture of 3 first formed 2D grid layers from 1D chains by intermolecular hydrogen bonds and then extended into a 3D structure through aromatic ,,, interactions. Furthermore, strong emissions from these complexes were also changed by the coordination modes in the solid state. However, complexes 1,3 show high thermal stability.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Crystal Structure, Solid-State NMR Spectroscopic and Photoluminescence Studies of Organic-Inorganic Hybrid Materials (HL)6[Ge6(OH)6(hedp)6]·2(L)·nH2O, L = hqn or phen,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 23 2006Luís Mafra Abstract Two germanium,hedp4, solids with heteroaromatic amines 8-hydroxyquinoline (hqn) and 1,10-phenanthroline (phen), (HL)6[Ge6(OH)6(hedp)6]·2(L)·nH2O (L = hqn or phen), in I and II respectively, have been prepared and characterised by single-crystal XRD, thermogravimetry, FTIR and UV/Vis spectroscopy. The complex hydrogen-bond networks, particularly in compound I, have been studied by advanced high-resolution solid-state NMR spectroscopy that combines homonuclear recoupling techniques (two-dimensional 1H- 1H DQF and 1H- 1H RFDR MAS NMR) and combined rotation and multiple-pulse spectroscopy (two-dimensional 1H- 1H FS-LG, 1H- 31P FS-LG). The fine details of the crystal structure of I have been elucidated, mainly those involving the ,,, stacking of 8-hydroxyquinoline and the relative orientation of adjacent such molecules. Compound II exhibits an emission from the lowest triplet-state energy (,,,* 0-phonon transition) of the aromatic rings at 320 nm (31250 cm,1) from 14 K to room temperature. In contrast, the triplet emission of I at 530 nm (18868 cm,1) is only detected at low temperature, because of thermally activated non-radiative mechanisms. The emission spectra of I and II display a lower-energy component with a larger life time, which results from the formation of an excimer state that originated from the ,,, phenanthroline and hydroxyquinoline interactions, respectively. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Tris(tropolonato)phenanthroline Lanthanide(III) Complexes as Photochemical DevicesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 12 2006Laura Bertolo Abstract The tris-tropolonato erbium(III) complexes [Er(hino)3(phen)] and [{Er(hino)3}2(pdon)] (H-hino = 2-hydroxy-6-isopropylcyclohepta-2,4,6-trien-1-one; phen = 1,10-phenanthroline; pdon = 1,10-phenanthroline-5,6-dione) have been prepared by reaction of [Er(hino)3]n with the appropriate chelating ligand in alcoholic solution. The complexes were characterized by elemental analyses, TG, ESI MS, 1H NMR, and IR spectroscopy, also by comparison with the properties of the analogous EuIII and YbIII complexes. The ESI-MS spectroscopy of the complex with the ditopic ligand pdon parallels the other physico-chemical data (IR, NMR), confirming the occurrence of a dinuclear entity. All the investigated ErIII complexes show efficient NIR emissions at about 1550 nm upon excitation at 355 nm in the UV ligand absorption band, emerging as possible candidate as active material for the realization of plastic amplifiers for telecommunications. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Oxidorhenium(V) Complexes of a Family of Bipyridine-Like Ligands Including Pyridyltriazines and Pyrazinyltriazine: Oxygen-Atom Transfer, Metal Redox and CorrelationsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 11 2006Samir Das Abstract The title ligands (general abbreviation L) are bipyridine (bpy), its dimethyl (mbpy) and diphenyl (pbpy) derivatives, phenanthroline (phen), 5,6-diphenyl-3-(2-pyridyl)-1,2,4-triazine (ppyt) and its dimethyl (mpyt) and pyrazinyl (ppzt) analogues. The concerned oxido complexes are [ReOCl3(L)],[ReOBr3(ppyt)] and [ReOBr3(ppzt)]. The chloro and bromo complexes of ppyt and ppzt were prepared by reacting these ligands with [ReOX3(AsPh3)2] (X = Cl, Br). The X-ray structures of [ReOCl3(ppyt)] and [ReOCl3(ppzt)] reveal that the ReCl3 fragment is meridionally disposed and that the L ligand is N,N -coordinated such that the pyridine/pyrazine nitrogen lies trans to the oxido oxygen atom. The Re,O lengths [1.656(10)/1.625(9) Å] correspond to approximate triple bonding. The rate of oxygen-atom transfer from [ReOX3(L)] to triphenylphosphane in solution follows second-order kinetics and is associated with a large and negative entropy of activation (approx. ,30 cal,K,1,mol,1). The initial attack is believed to involve the phosphane lone pair and Re,O ,*-orbitals. Electron withdrawal from the ReVO moiety by varying X or L facilitates oxygen-atom transfer. Thus, the rates follow the orders Br < Cl; mbpy < bpy < phen < pbpy << mpyt < ppyt < ppzt. The reduction potential of the quasireversible ReVIO/ReVO couple displays similar trends and the logarithmic rate constant of oxygen-atom transfer is found to correlate linearly with the reduction potential. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Synthesis and Luminescent Properties of Novel Europium(III) Heterocyclic ,-Diketone Complexes with Lewis Bases: Structural Analysis Using the Sparkle/AM1 ModelEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2005Rani Pavithran Abstract Tris(,-diketonato)europium(III) complexes of general formula [Eu(TPI)3·L], with chelating ligands such as 3-phenyl-4-(4-toluoyl)-5-isoxazolone (HTPI) and adduct-forming reagents [L = H2O, tri- n -octylphosphane oxide (TOPO), triphenylphosphane oxide (TPhPO), 1,10-phenanthroline], have been synthesized and characterized by elemental analysis and FT-IR, 1H NMR, and photoluminescence spectroscopy. The coordination geometries of the complexes were calculated using the Sparkle/AM1 (Sparkle model for the calculation of lanthanide complexes within the Austin model 1) model. The ligand,Eu3+ energy-transfer rates were calculated using a model of intramolecular energy transfer in lanthanide coordination complexes reported in the literature. The room-temperature PL spectra of the europium(III) complexes are composed of the typical Eu3+ red emission, assigned to transitions between the first excited state (5D0) and the multiplet (7F0,4). The results clearly show that the substitution of water molecules by TOPO leads to greatly enhanced quantum yields (i.e., 1.3,% vs. 49.5,%) and longer 5D0 lifetimes (220 vs. 980 ,s). This can be ascribed to a more efficient ligand-to-metal energy transfer and a less efficient nonradiative 5D0 relaxation process. The theoretical quantum yields are in good agreement with the experimental quantum yields, which highlights that the present theoretical approach can be a powerful tool for the a priori design of highly luminescent lanthanide complexes. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Tetracyanoquinodimethanido Derivatives of (Terpyridine)- and (Phenanthroline)metal Complexes , Structural and Magnetic Studies of Radical-Ion SaltsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 3 2005Cristina Alonso Abstract Several derivatives of formulae [M(terpy)2](TCNQ)2 or [M(terpy)2](TCNQ)3 (M = Ni, Cu, Zn; terpy = 2,2,:6,,2"-terpyridine; TCNQ= 7,7,8,8-tetracyanoquinodimethane) and [M(phen)3](TCNQ)2 or [M(phen)3](TCNQ)4 (M = Fe, Ni; phen = 1,10-phenanthroline) have been obtained. The crystal structures of [M(terpy)2](TCNQ)2 (M = Ni, Cu) show that the metal is surrounded by the terpyridine nitrogen atoms in a closed octahedral environment and the TCNQ anions are dimerised by , overlap. The cationic [M(terpy)2]2+ and the anionic [TCNQ]22, groups alternate in the crystal. For the derivatives with three TCNQ groups, the existence of a stack of trimeric [TCNQ]32, ions having electronic delocalisation is proposed. The compound [Fe(phen)3](TCNQ)2, which shows a strong interaction between TCNQ anions, led to the formation of a , bond in the diamagnetic species [TCNQ,TCNQ], while the nickel analogue is expected to have a localised structure formed by alternation of cationic metal complexes and dimeric [TCNQ]22, anions similar to those observed in the analogous terpy derivatives. The derivatives having four TCNQ groups also show electronic delocalisation and a 1D stack based on the magnetic data is proposed. (© Wiley-VCH Verlag GmbH & Co. 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