Inorganic Chemistry Communications (v.13, #5)

Contents List (iii-x).

A new cobalt complex, [Co(L)2·(H2O)2](HL = 4-hexanoyl-3-methyl-1-phenyl-1H -pyrazol-5(4H)-one), was synthesized by us. The complex was characterized by single crystal X-ray diffraction, IR, UV, fluorescence spectra and thermogravimetric analysis. The results of characterization showed that the crystal is monoclinic system with crystal parameters: a  = 15.2439(12) Å, b  = 7.4101(6) Å, c  = 15.7381(18) Å, and Z  = 2, S  = 1.074. It was found that the Co2+ is located in the inversion center of the complex. The Co(II) had an ideal octahedral coordination environment with four oxygen atoms of HL ligands in the equatorial plane and two water molecules in axial positions. The complex exhibits yellow emission as the result of the fluorescence from the intraligand emission excited state.A new cobalt complex, [Co(L)2·(H2O)2](HL = 4-hexanoyl-3-methyl-1-phenyl-1H -pyrazol-5(4H)-one), was synthesized by us. The complex was characterized by single crystal X-ray diffraction, IR, UV, fluorescence spectra and thermogravimetric analysis. The results of characterization showed that the crystal is a monoclinic system with crystal parameters: a  = 15.2439(12) Å, b  = 7.4101(6) Å, c  = 15.7381(18) Å, and Z  = 2, S  = 1.074. It was found that the Co2+ was located in the inversion center of the complex. The Co(II) had an ideal octahedral coordination environment with four oxygen atoms of HL ligands in the equatorial plane and two water molecules in axial positions. The complex exhibits yellow emission as the result of the fluorescence from the intraligand emission excited state.Display Omitted
Keywords: Acylpyrazolonate complex; Cobalt; Crystal structure; Fluorescence; Spectrum characterization;

Novel mixed valence U(VI)/U(IV) dipicolinate by Grigory Andreev; Nina Budantseva; Ivan Tananaev; Boris Myasoedov (577-579).
Mixed valence U(VI)/U(IV) compound with organic anionic ligand bridging uranium atoms in different oxidation states was synthesized at room temperature. Coordination polyhedron of U(VI) atom is a pentagonal bipyramide whose equatorial positions are occupied by nitrogen and two oxygen atoms of one DPA2− anion, oxygen atom of another DPA2− anion and a water molecule. Second uranium atom U(IV) is surrounded by three DPA2− anions, one of which is tetradentate and acts as bridging ligand connecting metal centers, while other two DPA2− anions are tridentate. The crystal structure is confirmed by UV–vis and IR spectroscopic data.Mixed valence U(VI)/U(IV) dipicolinate was synthesized in mild conditions. Its structure was determined using X-ray single structure diffractometry and confirmed by IR and UV–vis spectroscopic data.Display Omitted

18-Crown-6 as a linker for (imino ester)2Pt centers providing their assembly into 1D arrays via hydrogen bonding by Tatiana G. Chulkova; Pavel V. Gushchin; Matti Haukka; Vadim Yu. Kukushkin (580-583).
The platinum(II- and IV) complexes trans-[PtCl n {HN=C(OMe)Et}2] (n  = 2, 4) were assembled with 18-crown-6 into novel 1D arrays by hydrogen bonding thus forming 1:1 associates. The crystal structure determinations revealed the presence of the N–H⋯O and the non-conventional weak CH⋯O interactions between the imino hydrogen and the methyl hydrogens, respectively, of trans-[PtCl n {HN=C(OMe)Et}2] and the oxygens of 18-crown-6.The platinum(II- and IV) complexes trans-[PtCl n {HN=C(OMe)Et}2] (n  = 2, 4) are assembled with 18-crown-6 into novel 1D arrays by the non-conventional CH⋯O and the conventional NH⋯O hydrogen bondings.Display Omitted
Keywords: 18-Crown-6; Imino ester ligand; Platinum; Supramolecular chemistry; 1D arrays;

Crystallographic and computational investigation of nitrate salts of nickel(II) ethylenediamine complexes by Sandra A. Reisinger; Alvaro S. de Sousa; Manuel A. Fernandes; Christopher B. Perry; Pradeep R. Varadwaj; Helder M. Marques (584-588).
Two nitrate salts of Ni(II) and ethylenediamine (en), trans-diaquabis(ethylenediamine)nickel(II) nitrate (1) and Λ-δδδ-tris(ethylenediamine)nickel(II) nitrate (2), were investigated crystallographically and the nature of the intermolecular interactions in 2 were explored using the quantum theory of atoms in molecules (QTAIM) of Bader from a X3LYP/6–31 + G(d) single point calculation on a portion of the crystal structure. In 1 the two chelate rings, related by inversion, are in the λ and δ conformations, respectively. The metal complex cations are hydrogen bonded to the axial H2O ligands and the amino protons and pack in ribbons along the crystallographic a axis. In 2, which is the enantiometric form of the known Δ-λλλ-tris(ethylenediamine)nickel(II) nitrate, each nitrate is in a distorted tetrahedral site defined by [Ni(en)3]2+ cations. QTAIM analysis indicates that NO3 forms O····HN hydrogen bonds to amino groups of en, as well as a O····HC hydrogen bond to one of the methylene groups of the ligand. In addition, neighbouring [Ni(en)3]2+ ions are connected by a weak H–H bond between en methylene groups.The structures of trans-[Ni(en)2(H2O)2](NO3)2 and Λ-δδδ-[Ni(en)3](NO3)2 are reported. The nature of the intermolecular interactions in the latter are explored using the quantum theory of atoms in molecules.Display Omitted
Keywords: Nickel; Ethylenediamine; Intermolecular interactions; Molecular graph; Quantum theory of atoms in molecules;

On the reaction mechanism of MoS4 2− with nitric oxide by Inna Popivker; Israel Zilbermann; Eric Maimon; Dror Shamir; Naomi Meyerstein; Dan Meyerstein (589-592).
MoS4 2− (TTM) reacts in deaerated neutral phosphate buffered aqueous solutions with NO. Three consecutive reactions are observed. The two first ones obey pseudo first order rate laws with observed rates proportional to [NO]. The third reaction obeys a first order rate law. Nitrite is one of the final products.The mechanism proposed involves thiol nitrosation via a radical mechanism followed by hydrolysis of the S–N bond. The findings indicate that if MoS4 2− will be used as a drug, it will not affect considerably the NO concentration in the system.II. Mechanism B:Display OmittedIII. Mechanism C:Display OmittedMoS4 2− (TTM) reacts in deaerated neutral phosphate buffered aqueous solutions with NO. The mechanism proposed involves thiol nitrosation via a radical mechanism followed by hydrolysis of the S–N bond. The findings indicate that if MoS4 2− will be used as a drug, it will not affect considerably the NO concentration in the system.
Keywords: Tetrathiomolybdate; NO; Drug; Nitrosation; Radical mechanism;

Complexation and structural studies of a sulfonamide aza-15-crown-5 derivative by Marie Ioannidis; Alexander S. Gentleman; Lam Ho; Stephen F. Lincoln; Christopher J. Sumby (593-598).
An aza-15-crown-5 derivative, N-[4-(phenyldiazo)benzenesulfonyl]-aza-15-crown-5, 1 was synthesised from commercially available starting materials in 55% yield. Compound 1, which contains a sulfonamide link between the crown ether macroring and the azobenzene, readily binds alkali metals in buffered ethanol–water (75:25 v/v, pH 6.66). Titration data for both sodium and potassium were readily fitted to a 1:1 metal ion/ligand binding model to obtain stability constants (log K) of 4.7 ± 0.4 and 4.8 ± 0.2 dm3  mol− 1, respectively. We also investigated the structures of 1 and the sodium perchlorate salt of 1, [Na(1)(H2O)]2(ClO4)2, which were determined by X-ray crystallography. [Na(1)(H2O)]2(ClO4)2 is a dimer in the solid state whereby a sulfonamide oxygen atom from one of the [Na(1)(H2O)] cations provides solvation of the adjacent macroring bound sodium cation. In the crystal structure, binding of a water molecule to the sodium cation is supported by hydrogen bonding to the sulfonamide oxygen, which represents a supramolecular lariat ether-like interaction. N-[4-(phenyldiazo)benzenesulfonyl]-aza-15-crown-5, 1 was synthesised in 55% yield. Compound 1 binds both sodium and potassium to form 1:1 complexes with stability constants (log K) of 4.7 ± 0.4 and 4.8 ± 0.2 dm3  mol− 1, respectively. The structure of [Na(1)(H2O)]2(ClO4)2, was determined by X-ray crystallography to be a dimer in the solid state.Display Omitted
Keywords: Host–guest chemistry; Supramolecular chemistry; Azacrown ether; Lariat ether; Alkali metals;

Three novel Ln(III)–Cu(I) coordination polymers, namely [LnCu(Hbic)3(ox)0.5] [Ln = Sm (1), Dy (2), Hbic = benzimidazole-5-carboxylate, ox = oxalate] and [EuCu(Hbic)2(ox)H2O]·2H2O (3) have been hydrothermally synthesized and stucturally characterized. Both complexes 1 and 2 display the same unusual 2D layer heterometallic coordination frameworks that are built up by dimeric [Ln2(Hbic)6] cores and oxalate ligands by sharing Cu(I) ions. Complex 3 represents 1D polymeric chain architecture constructed from Eu2Cu2 ring units and oxalate ligands. Furthermore, the luminescent property of complex 3 has also been investigated.Three novel Ln(III)–Cu(I) coordination polymers, namely [LnCu(Hbic)3(ox)0.5] [Ln = Sm (1), Dy (2), Hbic = benzimidazole-5-carboxylate, ox = oxalate] and [EuCu(Hbic)2(ox)H2O]·2H2O (3) have been hydrothermally synthesized and stucturally characterized.Display Omitted
Keywords: Hydrothermal synthesis; Benzimidazole-5-carboxylic acid; 3d4f heterometallic complexes; Luminescence;

Novel W(II) complexes for reversible addition-fragmentation chain transfer (RAFT) polymerizations by Chuan-Lin Chen; Yih-Hsing Lo; Chia-Yi Lee; Yih-Hsuan Fong; Kuo-Chen Shih; Chiung-Cheng Huang (603-605).
Alkylation of the phosphorus coordination of the diphenyl(dithioformato)phosphine ligand in [W(CO)5(PPh2CS2)]NEt4 (1) at the S atom results in the formation of the novel RAFT agent S═C[W(CO)5PPh2]S–R (2a, R = CH2Ph; 2b, R = CH2CH═CH2). These compounds have been shown to be highly effective in reversible addition-fragmentation chain transfer (RAFT) polymerization to produce polymers (homopolymer and diblock copolymer) of predetermined molecular weight and narrow polydispersity (< 1.3). Electron-withdrawing organometallic substituents can increase the activity of RAFT agents. To the best of our knowledge, this is the first report of their use as RAFT agents in polymerization.Alkylation of 1 at the S atom results in the formation of the novel RAFT agent S═C[W(CO)5PPh2]S―R (2a, R = CH2Ph; 2b, R = CH2CH═CH2). These compounds have been shown to be highly effective in reversible addition-fragmentation chain transfer (RAFT) polymerization to produce polymers (homopolymer and diblock copolymer) of predetermined molecular weight and narrow polydispersity (< 1.3). To the best of our knowledge, this is the first report of their use as RAFT agents in polymerization.Display Omitted
Keywords: W(II); Diphenyl(dithioformato)phosphine; Reversible addition-fragmentation chain transfer (RAFT) polymerization; Narrow polydispersity;

A novel fluorescent chemosensor for Zn(II) based on 1,2-(2′-oxoquinoline-3′-yl-methylideneimino)ethane by Zeng-chen Liu; Bao-dui Wang; Zheng-yin Yang; Tian-rong Li; Yong Li (606-608).
A new bis Schiff-base ligand (1,2-(2′-oxoquinoline-3′-yl-methylideneimino)ethane, QSB) derived from 2-oxo-quinoline-3-carbaldehyde and ethylene diamine was synthesized and characterized by 1H-NMR. Spectroscopic investigation revealed that the compound exhibited a high selectivity toward Zn(II) ion over other metal ions in acetonitrile solution. In addition, the crystal structure showed that the coordination form of QSB and Zn(II) was 1:1.A novel bis Schiff-base fluorescent chemosensor (1,2-(2′-oxoquinoline-3′-yl-methylideneimino)ethane) was synthesized and characterized. The high selectivity for Zn(II) was investigated systemically by UV-Vis and fluorescence spectra.Display Omitted
Keywords: Bis Schiff-base; Fluorescence sensor; Crystal structure; Zn(II) complex;

New estertin derivatives based on trivacant Keggin-type [β-SbW9O33]9 cluster by Lan-Cui Zhang; Han Xue; Zai-Ming Zhu; Qiu-Xue Wang; Wan-Sheng You; Yang-Guang Li; En-Bo Wang (609-612).
Two new polyoxometalate-based estertin derivatives, Na6K4[{Sn(C3H4O2)}2{Sn(C3H4O2)(H2O)}2·(B-β-SbW9O33)2]·14H2O (1) and Na4K6[{Sn(C4H6O2)(H2O)}2(WO2)2(B-β-SbW9O33)2]·19H2O (2), have been synthesized by the reaction of Na9[B-α-SbW9O33]∙19.5H2O with Cl3Sn(CH2)2COOCH3 or Cl3SnCH2CH(CH3)COOCH3 in an aqueous KCl solution. Both compounds exhibit the sandwich-type structural feature, in which the carboxyethyltin fragments are sandwiched by two B-β-[SbW9O33]9 units. Structural analyses reveal that the reaction process involves α  →  β isomerization of [SbW9O33]9 unit and the hydrolysis of estertin into carboxyethyltin group. Both compounds display good electrocatalytic activities toward the reduction of hydrogen peroxide, and compound 1 also shows good anti-tumoral activities in vitro.Two new estertin derivatives based on the trivacant Keggin-type B-β-[SbW9O33]9 polyoxoanion are obtained, displaying good electrocatalytic activities and anti-tumor abilities.Display Omitted
Keywords: Polyoxometalate; Tungstoantimonate; Estertin derivatives; Sandwich-type structure; Electrocatalysis; Anti-tumor;

Synthesis, crystal structure and photophysical properties of a novel Pt(II) complex with multi-functionalized cyclometalating ligand by Dongfang Qiu; Yuquan Feng; Hongwei Wang; Xiaoyu Bao; Yingchen Guo; Yanxiang Cheng; Lixiang Wang (613-617).
A novel Pt(II) complex [(L)PtCl] (HL = 4-{p-[N-(4-(9-carbazole))butyl-N-phenyl] aniline}-6-phenyl-2,2′-bipyridine) has been synthesized and verified by 1H NMR, elemental analysis and X-ray crystallography. The crystal (C44H35N4ClPt, M r  = 850.30) belongs to monoclinic system, space group P2(1)/c, with a  = 21.864(6), b  = 9.306(3), c  = 17.240(5) Å, β  = 96.483(6)°, Z  = 4, V  = 3485.3(16) Å3, D C  = 1.620 g/cm3, μ(Mo-Kα) = 4.141 mm− 1, F(000) = 1688, R 1  = 0.0591, wR 2  = 0.0976. The coordinate geometry of the Pt atom is a distorted square planar configuration. The complex molecules are stacked by a weak π–π interaction in a head-to-tail fashion along the b axis to form 1D chain and the alternating 1D chains are packed to form the 2D lamellar system. The complex shows an intense metal-to-ligand charge transfer (1MLCT) ((Pt) →  π*(L)) transitions (ε ∼ 2 × 104  dm3 mol− 1 cm− 1) at 448 nm in the UV–Vis absorption spectrum and a strong phosphorescence at 592 nm in CH2Cl2 solution at room temperature. An intramolecular energy transfer process from the carbazole unit to the arylamine-modified [(C^N^N)PtCl] emissive center exists in the complex.The tri-component C^N^N Pt (II) complex: the neutral-charged C^N^N Pt (II) halide with aniline and carbazole functionalized cyclometalating ligand form 1D chains in a head-to-tail fashion along the b axis by weak π–π interactions and 2D lamellar system. The complex shows a intense metal-to-ligand charge transfer (1MLCT) ((Pt) →  π*(L)) transitions at 448 nm in the UV–Vis absorption spectrum and a strong phosphorescence at 592 nm in CH2Cl2 solution at room temperature.Display Omitted
Keywords: Platinum (II); Cyclometalated; Multi-functionalized; Crystal structure; Photophysics;

SOD mimic activity, DNA binding and in-vitro antibacterial studies of drug based copper(II) complexes by Mohan N. Patel; Deepen S. Gandhi; Pradhuman A. Parmar (618-621).
Square pyramidal complexes [CuII(PFL)(bpa)Cl]∙5H2O (1) and [CuII(LFL)(bpa)Cl]∙5H2O (2) have been synthesized and characterized. Compounds were checked for their in-vitro antimicrobial activity against two Gram(+ ve) and three Gram(–ve) bacterial species. Intrinsic binding constant (K b) of complexes with CT DNA were determined using absorption titration. Viscosity measurement suggests that complexes bind with CT DNA through partial nonclassical intercalative mode. Superoxide dismutase (SOD) like activity of the complexes was also compared with previously reported compounds.Partial non-classical intercalators with diverse biological activity were prepared using fluoroquinolones. They showed better superoxide scavenging ability.Display Omitted
Keywords: Square pyramidal; Fluoroquinolone; FAB–MS; CT DNA; SOD;

Unexpected formation of ammonium thiocyanate from the reaction of aqueous hydroxylamine with carbon disulfide by Muddamarri Hanumantha Rao; Raghavaiah Pallepogu; Krishnamurthi Muralidharan (622-624).
Reaction of aqueous hydroxylamine with carbon disulfide in acetonitrile or in tetrahydrofuron unprecedentedly results in the formation of ammonium thiocyanate and sulfur.Reaction of aqueous hydroxylamine with carbon disulfide in acetonitrile or in tetrahydrofuron unprecedentedly results in the formation of ammonium thiocyanate and sulfur.Display Omitted
Keywords: Ammonium thiocyanate; Carbon disulfide; Hydroxylamine; Hydroxy isothiocyanate;

Embrace interlocking of dipyrazinylpyridine complexes involving N⋯π interactions by Jing-Wei Dai; Ben-Zhen Li; Ying-Lin Chen; Guang Huang; Bin Cai; Ying Yu; Jian-Zhong Wu (625-629).
Fe(II) and Ni(II) complexes of 4-p-tolyl-2,6-di(2-pyrazinyl)pyridine (tdpzpy) have been synthesized and characterized. The N⋯π interaction involving the uncoordinated pyrazinyl N atom, which is stronger than the corresponding C–H⋯π hydrogen bonding in a similar 4-p-tolyl-2,2′:6′,2″-terpyridine complex, was distinguished as a supramolecular motif. It acts as an edge-to-face force in assembling cations of [Fe(tdpzpy)2]2+ or [Ni(tdpzpy)2]2+ into chains via embrace interlocking. C–H⋯π hydrogen bonds further link the chains into higher dimension net. The electronic absorption and emission properties of [Fe(tdpzpy)2]2+ and [Ni(tdpzpy)2]2+ are largely ligand-centered. [Fe(tdpzpy)2]2+ displays an MLCT absorption at 567 nm. The fluorescence of [Ni(tdpzpy)2]2+ is different markedly in methanol and acetonitrile. The ligand-based fluorescence is quenched to some extent by coordination to the d-orbital unfulfilled Fe(II) or Ni(II) atom.N⋯π interaction, similar to but stronger than the C–H⋯π hydrogen bonding, was identified as a supramolecular edge-to-face force as discovered in assembly of dipyrazinylpyridine complex cations.Display Omitted
Keywords: Crystal structure; N⋯π interaction; C–H⋯π hydrogen bond; Electronic absorption; Fluorescence;

Structure and luminescent property of a novel one-dimensional organomercury complex by Ying Liu; Peng-Fei Yan; Ying-Hui Yu; Guang-Feng Hou; Jin-Sheng Gao (630-632).
A novel organomercury complex, [Hg2(μ-CH3COO)(CH3COO)(L)] n (L = 1,3-bis(pyridine-2-ylmethoxy)benzene) 1, has been synthesized. Complex 1 has a one-dimensional chain structure formed by acetate anions bridging Hg(II) atoms in crystallographical c-axis. The orthomercuration of the ligand takes place at C-4 and C-6 of benzene ring rather than C-2 position. It shows intense fluorescent emission by solid-state luminescent analysis.A novel organomercury complex has been synthesized, [Hg2(μ-CH3COO)(CH3COO)(L)]n, which is a one-dimensional chain formed by acetate anions bridging Hg(II) atoms in c-axis. The orthomercuration of the ligand takes place at C-4 and C-6 of benzene ring rather than C-2 position.Display Omitted
Keywords: Organomercury complex; Bipyridine ligand; X-ray structure; Luminescent property;

Kinetic studies of the oxidation of quercetin, rutin and taxifolin in the basic medium by (ethylenediaminetetraacetato) cobalt(III) complex by Lu-Ming Lin; Han-Ying Wu; Wei-Shuen Li; Wei-Lin Chen; Yean-Jang Lee; Da Cheng Wu; Ping Li; Andrew Yeh (633-635).
The quercetin in 0.01 M NaOH solution underwent steady oxidation when it was exposed to air with the formation of the quinone product. For the taxifolin and rutin, the oxidation occurred only when the solutions were saturated with O2, but very slowly. The kinetics of the oxidation of flavonoids in 0.01 M NaOH solution by Co(edta) complex was carried out and the rate constants are 3.44 × 102, 1.04 × 10− 1 and 1.46 × 10− 2  M− 1  s− 1 for quercetin, rutin and taxifolin, respectively, at μ  = 0.10 M LiClO4. The deprotonation of the C3 hydroxyl group and the conjugation between pyrone and catechol rings account for the reactivity of quercetin.The quercetin in 0.01 M NaOH solution underwent steady oxidation to form quinone product when it was exposed to air. The rate constant of oxidation in the alkaline solution by Co(edta) complex was found to be greater than those of taxifolin and rutin by more than three orders of magnitude. The deprotonation of the C3 hydroxyl group and the conjugation between pyrone and catechol rings account for the reactivity of quercetin.Display Omitted
Keywords: Quercetin; Rutin; Taxifolin; Co(edta);

Solvent control on the structural versatility and properties of manganese(II) complexes surrounded by the flexible hinge-like ligand by Ryuta Ishikawa; Koichi Yamada; Seigo Yamauchi; Ryo Miyamoto; Satoshi Kawata (636-640).
Four different types of polynuclear manganese(II) compounds with bhnq2− bridges were obtained from the reaction of Mn(CH3COO)2·4H2O with the flexible hinge-like ligand H2bhnq (H2bhnq = 2,2′-bi(3-hydroxy-1,4-naphthoquinone)) by controlling the reaction solvent: [Mn3(bhnq)3(H2O)2]·10.5H2O (1), [Mn2(bhnq)2(DMSO)4]·2DMSO·CHCl3 (2), {[Mn(bhnq)(H2O)2]·2H2O} n (3), and {[Mn(bhnq)(DMF)2]} n (4). All complexes are neutral with the same Mn/bhnq 1:1 formulation ratio. Compounds 1 and 2 are discrete systems, while compounds 3 and 4 are one-dimensional ones. All compounds were characterized by X-ray diffraction and show different coordination modes for the bhnq2− ligand.Four different types of polynuclear manganese(II) compounds were obtained with the molecular hinge-like ligand bhnq2− by controlling the reaction solvent. There is a structural diversity among the Mn–bhnq complexes. The topology of the structures is easily controlled by the selection of the solvent.Display Omitted
Keywords: Structure elucidation; Supramolecular chemistry; Bridging ligands; Helical structures;

A 3D-diamond-like coordination network of lead(II) complex: Synthesis, structure and luminescent property by Ying-Ying Zhang; Shi-Xiong Liu; Kang-Kai Du; Mei-Xiang Xue (641-644).
A lead(II) complex [Pb(Hfysh)2] (1) (H2fysh = furan-2-ylmethylene salicyloyl hydrazone) has been synthesized and characterized. The lead atom is in a holodirected eight-coordinated polyhedron. There are secondary Pb–O interactions that give rise to a novel 3D-diamond-like coordination network. The luminescent property of 1 in the solid state was investigated.The solution reaction of Pb(NO3)2 with furan-2-ylmethylene salicyloyl hydrazone (H2fysh) afforded a new 3D-diamond-like coordination polymer [Pb(Hfysh)2]. The lead(II) atom is in a holodirected eight-coordinated polyhedron.Display Omitted
Keywords: Lead(II) complex; Coordination polymer; Diamond-like network; Luminescent property;

Three new Cu and Cd complexes, namely [Cu(phen)(isca)(EtOH)] (1),[Cu(phen)2(HCOOH)] (2) and [Cd(phen)Cl2](3) (phen = 1, 10-phenanthroline, isca = isophthalic acid) have been synthesized, which are characterized by elemental analysis, infrared spectrum and x-ray crystal diffraction. While strong hydrogen bonds play central roles in the formation of the 3D structure, the combined influence of the weak interactions such as C-H···O bonds, C-H···π and lone pair···π interactions are also evident in the structures. The preliminary investigation on the thermal and fluorescence property of the complexes are presented.The combined influence of the weak interactions such as C-H···O bonds, π···π and lone pair···π interactions play important roles in the formation of the structures.Display Omitted
Keywords: crystals structure; weak interactions; fluorescence; 1, 10-phenanthroline;

A 3-D lanthanum-organic framework containing double chains: La2[NC5H3(CO2)2]3·3H2O by Dat T. Tran; Deryn Chu; Allen G. Oliver; Scott R.J. Oliver (649-652).
A three-dimensional La(III) based metal-organic framework, La2[NC5H3(CO2)2]3·3H2O, was assembled using the aromatic linker 3,5-pyridinedicarboxylate. This new compound was synthesized hydrothermally and is an unusual example of a lanthanum containing metal-organic network. The compound contains two distinct La centers, each adopting a nine-coordinate geometry. The structure is built up from zig-zag chains that link via bridging water molecules into a double chain defining edge-sharing six rings. These double chains are arranged into layers and connect through 3,5-pyridinedicarboxylate ligands to give the extended 3-D coordination framework. The material is thermally stable to ca. 360 °C and transforms to an unknown compound before finally decomposing to phase-pure La2O3 at 800 °C. The synthesis, structure, morphology and properties of the new material are described.A three-dimensional La(III) based metal-organic framework, lanthanum 3,5-pyridinedicarboxylate, La2[NC5H3(CO2)2]3·3H2O, is described. The structure consists of zig-zag chains, which link together into double chains embedded within the 3-D lanthanum-organic framework.Display Omitted
Keywords: Hydrothermal synthesis; 3,5-Pyridinedicarboxylate; Lanthanum; Metal-organic framework; Zig-zag chains; Double chains;

Cyclopalladation of 2-tert-butyl-4,4-dimethyl-2-oxazoline in solution and on silica gel by Valeria A. Stepanova; Jonathan E. Kukowski; Irina P. Smoliakova (653-655).
Cyclopalladation of 2-tert-butyl-4,4-dimethyl-2-oxazoline (1) using Pd(OAc)2 was performed in acetic acid and on silica gel. Treatment of the crude product formed in each reaction with LiCl afforded a dimeric cyclopalladated complex (4) in 76 and 93% yield, respectively. The 1H, 13C{1H} NMR and IR spectroscopy data for complex 4 confirmed the formation of the palladacycle with an (sp3)C–Pd bond and suggested the presence of two geometrical isomers in solution.Cyclopalladation of 2-tert-butyl-4,4-dimethyl-2-oxazoline (1) using Pd(OAc)2 can be accomplished either on SiO2 or in AcOH. Treatment of the crude product formed in each reaction with LiCl afforded complex 4 with an (sp3)C–Pd bond in 93 and 76% yield, respectively. The 1H, 13C{1H} NMR and IR data of oxazoline 1 and complex 4 are reported.Display Omitted
Keywords: Cyclopalladated complex; Metalation on silica gel; Oxazoline; Solvent-free reaction;

The syntheses, X-ray crystal structures and topological analyses of two supramolecular coordination complexes, [Co(H2O)4(ps)2] 1 and [Cu(H2O)2(ps)2] 2 (ps  = pyridine-3-sulfonic anion), are reported. Although the basic coordination environments and patterns around the metal centers of 1 and 2 are similar, the overall topologies of the two complexes are very different due to the formation of distinct hydrogen bonding interactions resulting from organosulphonate ligands.Two supramolecular coordination complexes, [Co(H2O)4(ps)2] 1 and [Cu(H2O)2(ps)2] 2 (ps  = pyridine-3-sulfonic anion), are reported. Although the basic coordination environments and patterns around the metal centers of 1 and 2 are similar, the overall topologies of the two complexes are very different due to the formation of distinct hydrogen bonding interactions resulting from organosulphonate ligands.Display Omitted
Keywords: X-ray crystal structures; Topological analyses; Hydrogen bonding; Organosulphonate;

Lanthanide complexes with 8-quinolinyloxyacetate (qoa): Synthesis and supramolecular assembly by hydrogen bonds by Jun Fan; Zhi-Hong Wang; Zhuo-Fen Huang; Xia Yin; Wei-Guang Zhang (659-662).
Two new lanthanide supramolecular complexes, [Tb(qoa)2(H2O)2]⋅NO3 ⋅ H2O (1) and [Er(qoa)3] ⋅ 2H2O (2) [qoa = (8-quinolinyloxy)acetate] were obtained by treating the corresponding nitrates and (8-quinolinyloxy)acetic acid (Hqoa) under hydrothermal conditions. Complex 1 possesses a 1D zigzag chain bridged by the qoa anions, which is further connected to form a 3D supramolecular framework via hydrogen bonds and π–π attractions. Compound 2 is a mononuclear structure and the coordination units are further assembled to a 1D helical chain parallel to the b-axis via hydrogen bonds. Obviously, various coordination modes of the qoa anions and the intermolecular attractions have effect on the formations of two complexes. The solid-state luminescent behavior of 1 has been investigated at room temperature.Two new lanthanide complexes exhibit different structure features, namely, a 1D zigzag chain and a helical chain. Various coordination modes of the ligands have influenced the formation of these complexes.Display Omitted
Keywords: Lanthanide; (8-Quinolinyloxy)acetate; Hydrogen bonding; Supramolecular assembly; Luminescence;

Improving the relaxivity by dimerizing Gd-AAZTA: Insights for enhancing the sensitivity of MRI contrast agents by Eliana Gianolio; Kondareddiar Ramalingam; Bo Song; Ferenc Kalman; Silvio Aime; Rolf Swenson (663-665).
The synthesis of a dimeric derivative of Gd-AAZTA is reported. It retains the basic properties of the parent complex (q  = 2, high stability) and displays a relaxivity of 14.0 mM 1  s 1 at 20 MHz and 298 K. The outstanding relaxivity is the result of the increased molecular reorientational time and of the contribution arising from 4 to 5 water molecules in the second coordination sphere of the Gd(III) ions.Oustanding relaxometric properties of a new dimeric derivative of Gd-AAZTA. It retains the basic properties of the parent complex (q  = 2, high stability) and displays a relaxivity of 14.0 mM 1  s 1 at 20 MHz and 298 K. Display Omitted
Keywords: Gadolinium chelate; MRI imaging; Relaxivity;

Five group 4 metal complexes (1)2Zr(NMe2)2 (5), (2)2Ti(NMe2)2 (6), (2)2Zr(NMe2)2 (7), (3)2Zr (8) and (4)2Ti(NMe2)2 (9) have been readily prepared from the reaction between M(NMe2)4 (M = Ti, Zr) and chiral binaphthyldiamine-based ligands, (R)-2,2′-bis(diphenylthiophosphoramino)-1,1′-binaphthyl (1H2), (R)-5,5′,6,6′,7,7′,8,8′-octahydro-2,2′-bis(diphenylthiophosphoramino)-1,1′-binaphthyl (2H2), (R)-5,5′,6,6′,7,7′,8,8′-octahydro-2,2′-bis(methanesulphonylamino)-1,1′-binaphthyl (3H2), and C 1-symmetric ligand, (R)-2-(mesitylenesulphonylamino)-2′-(dimethylamino)-1,1′-binaphthyl (4H). All the complexes have been characterized by various spectroscopic techniques, elemental analyses and X-ray diffraction analyses. The zirconium amides are active catalysts for the asymmetric hydroamination/cyclization of aminoalkenes, affording cyclic amines in good yields with moderate ee (enantiomeric excess) values.A new series of chiral group 4 metal complexes have been prepared. The zirconium amides are effective catalysts for the asymmetric hydroamination/cyclization of aminoalkenes, affording cyclic amines in good yields with moderate ee values.Display Omitted
Keywords: 2,2′-Diamino-1,1′-binaphthyl; Chiral group 4 metal complexes; Synthesis; Crystal structure; Asymmetric hydroamination/cyclization;

Via solvothermal reaction of CoCl2 with H3BTC (1,3,5-benzenetricarboxylic acid) in DMF–C2H5OH, a new metal–organic framework (MOF) was isolated. The single crystal X-ray diffraction suggests that the asymmetric unit contains six crystallography-independent Co(II) ions and four deprotonated BTC3− ligands, and the overall structure of it is a 3D microporous framework with three-dimensional intersecting channel. Further topological analysis reveals a highly rare (3, 4, 5, 6)-connected net.Via solvothermal reaction of CoCl2 with H3BTC (1,3,5-benzenetricarboxylic acid) in DMF–C2H5OH, a new metal–organic framework (MOF) was isolated. The single crystal X-ray diffraction suggests that the asymmetric unit contains six crystallography-independent Co(II) ions and four deprotonated BTC3 ligands, and the overall structure of it is a 3D microporous framework with three-dimensional intersecting channel. Further topological analysis reveals a highly rare (3, 4, 5, 6)-connected net.Display Omitted
Keywords: MOF; Multi-nodal framework; Porous materials; Phase transition;

Interactions of Cr(VI) and Cr(III) with isolated rat liver mitochondria by Alessandra Iero; Sabrina Manente; Silvia De Pieri; Eranda Mane; Michele Gallo; Francesca Cima; Loriano Ballarin; Marcantonio Bragadin (676-678).
The mechanism of interaction of Cr(VI) with isolated rat liver mitochondria was investigated in this study. The results suggest that Cr(VI) induces the opening of the membrane permeability transition pore (MPT). The phenomenon is cyclosporine-sensitive and is in agreement with the cyclosporine-sensitive apoptosis observed in the cells incubated with this compound. Moreover the action of Cr(III), that is formed in the cells by a reduction of Cr(VI), has been also analysed. The results obtained demonstrated that the Cr(III) does not induce the opening of the MPT in isolated mitochondria, but it has a protective effect in preventing Cr(VI) MPT opening. Therefore, these results suggest that apoptosis is regulated by a balance between Cr(VI) accumulation in the cytoplasm and Cr(III) formation.The Cr(VI) enters the cell using a physiological carrier and apoptosis is induced. The uptake is followed by formation of Cr(III) (probably by glutathione) and opening of the mitochondrial MPT pore. The MPT opening and apoptosis are due to the Cr(VI) or to the Cr(III) form?Display Omitted
Keywords: Chromium; Mitochondria; Apoptosis; MPT;

Cation–cation interaction in novel Np(V) compound with methylimidazole as a model of histidine side chain by Grigory Andreev; Nina Budantseva; Ivan Tananaev; Boris Myasoedov (679-682).
The reaction of NpO2(CH3SO3) with methylimidazole results in the formation of novel Np(V) complex with cation–cation interaction, [NpO2(MeIm)(CH3SO3)(H2O)]. The crystal structure is confirmed by IR and UV–vis spectroscopic data.Reaction of Np(V) methansulfonate with methylimidazole led to the formation of complex as determined using X-ray single crystal diffractometry. The crystal structure is confirmed by IR and UV–vis spectroscopic data. Display Omitted
Keywords: Neptunium; Actinides; Transuranium elements; X-ray structure; IR spectroscopy; Electron spectroscopy; Coordination chemistry;

Capturing copper(II) ions using {Cu(tpy)(bpy)} domains by Edwin C. Constable; Catherine E. Housecroft; Jason R. Price; Jennifer A. Zampese (683-685).
The reaction of 6,6"'-dimethyl-2,2':6',2":6",2'"-quaterpyridine (2) with 2,2':6',2"-terpyridine (tpy) and Cu(NO3) · 3H2O leads to the formation of [Cu(tpy)(2)]2+ and [Cu2(tpy)2(2)]4+, isolated as the hexafluoridophosphate salts. Single crystal structures of [Cu2(tpy)2(2)][PF6]4·2H2O and [Cu(tpy)(2)][PF6]2·MeCN are presented and illustrate the special stability of the 5-coordinate {Cu(tpy)(bpy)}2+ motif in mono- and dinuclear environments.The special stability of the 5-coordinate {Cu(tpy)(bpy)}2+ motif in mono- and dinuclear environments is illustrated in the reaction of 6,6"'-dimethyl-2,2':6',2":6",2'"-quaterpyridine (2) with 2,2':6',2"-terpyridine (tpy) and Cu(NO3)·3H2O which gives [Cu(tpy)(2)]2+ and [Cu2(tpy)2(2)]4+, isolated as the hexafluoridophosphate salts.Display Omitted
Keywords: Heterocycle; Oligopyridine; Copper; Helicate; Crystal structure;

Synthesis of new red photoluminescent Zn(II)-salicylaldiminato complex by Vincenzo Liuzzo; Werner Oberhauser; Andrea Pucci (686-688).
We report the preparation and photophysical properties of a new zinc (II) complex of the donor–acceptor–donor (D–A–D) type ligand N,N′-bis(2-hydroxy-1-naphthylidene)-diaminomaleonitrile (H2L). The molecular structure of the [(ZnL)·DMF]·DMF complex was determined by single crystal X-ray crystallography. The complex exhibits remarkable optical features attributed to the intramolecular charge transfer (ICT) with a striking red emission. Fluorescence studies of H2L and ZnL reveal that the quantum yield strongly increases upon coordination.The synthesis, characterization and photophysical proprieties of a new zinc (II) complex of the donor–acceptor–donor (D–A–D) type ligand N,N′-bis(2-hydroxy-1-naphthylidene)-diaminomaleonitrile (H2L1) are described. Fluorescence property studies of H2L and ZnL reveal that the quantum yield strongly increase upon coordination.Display Omitted
Keywords: Tetradentate; Schiff base; Zinc; Luminiscence;