Inorganic Chemistry Communications (v.6, #5)

Contents List (iii-v).

Synthesis and characterization of a novel iron (III) silsesquioxane compound by Michael T. Hay; Brandan J. Hainaut; Steven J. Geib (431-434).
A new iron (III) containing silsesquioxane compound, [Bu4N][((CH3)2CHCH2)7Si7O12FeCl] (4) was prepared by reacting [Bu4N][FeCl4] (3) with the isobutyl substituted silsesquioxane trisilanol, ((CH3)2CHCH2)7Si7O12H3, (1) in the presence of three equivalents of triethylamine, Et3N (2). The magnetic susceptibility of 4 was measured by Evans method, and the effective magnetic moment, μ eff, is consistent with a high spin Fe (III) center. The composition and molecular structure of 4 was fully determined by IR, elemental analysis, APCI mass spec, and X-ray crystal analyses, and its potential as a precursor to a model of the structure and chemistry of the Fe-ZSM-5 catalyst is discussed.
Keywords: Silsesquioxane; Metallasilsesquioxane; Iron complexes; Crystal structures;

Direct and improved synthesis of the tri-nickel sandwich-type polyoxoanion [Ni3Na(H2O)2(PW9O34)2]11− by Israel Martyr Mbomekalle; Bineta Keita; Louis Nadjo; Patrick Berthet (435-438).
The direct use of preformed B,α-Na9PW9O34 was successful in improving the synthesis of Na11[Ni3Na(H2O)2(PW9O34)2]·14H2O. The complex was characterized by elemental analysis, IR spectroscopy, magnetic properties and cyclic voltammetry. The yield was increased to 30%, which is four times more than that obtained in the initial synthesis. The delay before the appearance of the first crystals is drastically shortened, from months to hours, and these crystals are predominantly those of the yellow compound of interest. Keys to these improvements are the use of freshly prepared B,α-Na9PW9O34 through prolonged heating of A,β-Na9PW9O34 and the increase of the concentrations of the reactants in a close-to-neutral pH medium. Starting the synthesis with several concentrations of preformed A,β-Na9PW9O34 revealed the importance of the concentrations of reactants in speeding up the formation of crystals and suggested strongly that the [A-PW9O34]9−→[B-PW9O34]9− isomerization might be the slow step in the whole process. Cyclic voltammograms as well as X-ray diffraction structure determination confirm that the synthesized compound is indeed Na11[Ni3Na(H2O)2(PW9O34)2]·14H2O. A study of the magnetic properties of Na11[Ni3Na(H2O)2(PW9O34)2]·14H2O indicates that the three nickel centres exhibit ferromagnetic exchange interactions.
Keywords: Trivacant Keggin species; Sandwich-type species;

Modulation of photoinduced energy-transfer between Ru(II) and Os(II) termini in a dinuclear complex by a conformational change induced by Ba2+ binding at a central macrocyclic site by Rowena L Paul; Angeles Farrán Morales; Gianluca Accorsi; Thomas A Miller; Michael D Ward; Francesco Barigelletti (439-442).
In a dinuclear complex containing {Ru(bpy)3}2+ and {Os(bpy)3}2+ termini separated by a flexible diaza-18-crown-6 macrocyclic spacer, binding of a Ba2+ ion at the central macrocycle results in an increase in the Ru⋯Os separation for electrostatic reasons, and hence a decrease in the efficiency of Ru→Os photoinduced energy-transfer.

Acetophenone was enantioselectively reduced to 1-phenylethanol (21–71% e.e.) by the use of base-modified Ir and Rh catalysts derived from optically active β-aminophosphines, [{(1R,2S)-, (1R,2R)-, (1S,2S)-Ph2PCH(Ph)CH(Me)N(H)R}M(COD)]BF4–KOH (R=H, Me, i-Pr, CH2Ph), in methanol under H2 (10 bar). The isolation of an equally active amidoiridium catalyst, [(Ph2PCH2CMe2NH)Ir(COD)], its ability to oxidatively add dihydrogen, and the observation of both H2/D+ and H2/D2 exchange reactions during catalysis, which crucially depends on the use of protic solvents, provided evidence for a mechanism involving hydride and proton transfer as well as heterolytic H2 cleavage on dihydrogen–hydrido–amido and dihydrido–amine tautomers, [{‘P∩NR’}Ir(H2)H]+ and [{‘P∩N(H)R’}IrH2]+, respectively.
Keywords: Chirality; P,N ligands; Iridium; Rhodium; Catalysis; Hydrogenation;

Synthesis of (μ-alkoxo)bis(μ-carboxylato)diruthenium complex having porphyrin moieties as a potential photo-harvesting functionality by Norie Tanihara; Makoto Obata; Masafumi Harada; Yuji Mikata; Akihisa Hamazawa; Isamu Kinoshita; Kiyoshi Isobe; Akio Ichimura; Mikio Hoshino; Masahiro Mikuriya; Shigenobu Yano (447-450).
The ligand substitution reaction of K[Ru2(dhpta)(μ-O2CCH3)2] (H5dhpta=1,3-diamino-2-hydroxypropanetetraacetic acid) with zinc 5-(4-carboxylphenyl)-10,15,20-triphenylporphyrin (ZnTPP-p-COOH) afforded a diruthenium complex having porphyrin moieties, K[Ru2(dhpta)(μ-O2C-p-ZnTPP)2]. This product was characterized by UV–Vis and 1 H NMR spectroscopy, and EXAFS analysis.
Keywords: Ruthenium complex; Porphyrin derivatives; EXAFS analysis;

A one-pot method for the preparation of [Pd{[(η5-C5H3)–CHN–(CH2)2–NMe2]Fe(η5-C5H5)}Cl] is described. Its X-ray crystal structure and its reactions with the diphosphines Ph2P–(CH2) n –PPh2 {with n=1 (ddpm) or 2 (dppe)} are also reported.

Syntheses and X-ray determined single-crystal structures of thermally stable palladium(II) compounds involving π⋯π and C–H⋯π interactions which show selectivity to small organic molecules.
Keywords: Palladium(II) compounds; Selective absorption;

Chelating effect in 4(5)-hydroxymethyl-5(4)-methylimidazole complexes by Krystyna Kurdziel; Tadeusz Głowiak; Julia Jezierska (459-461).
Light pink crystal of composition [Co(4-CH2OH-5-CH3im)4](NO3)2 (where 4-CH2OH-5-CH3im denotes 4-hydroxymethyl-5-methylimidazole) were obtained from 2-propanol. The complex has been characterized by single-crystal X-ray as well as by electronic and vibrational spectroscopy. The immediate surrounding of the central ion is made up of four nitrogen atoms of the heterocyclic rings and two oxygen atoms of the hydroxymethyl group (CoN4O2 chromophore) The shape of the coordination polyhedron of the cobalt(II) ion is that of a slightly distorted octahedral.
Keywords: Imidazole derivatives; Cobalt(II) complex; Crystal structure; Electronic spectra;

Facile access to enantiomerically pure bis(sulfoxide) chelates of late transition metals by Daniel R. Evans; Mingsheng Huang; W. Michael Seganish; James C. Fettinger; Tracie L. Williams (462-465).
Herein contains a report detailing the synthesis and characterization of six, chiral, late-transition metal complexes all chelated using RS,RS-bis(p-tolylsulfinyl)ethane, RS,RS-BTSE. All complexes revealed S-ligation to the metal with an expected contraction of the sulfinyl-oxygen bond length when compared to free sulfoxide. The presented data serve to illustrate three attractive, yet unexplored, aspects of the bis(sulfoxide) bidentate ligand: (i) bidentate sulfoxide ligands, when chelated to a metal, give rise to complexes that are pseudo-C2 symmetric in terms of both sterics and electronics, (ii) the sulfoxides, unlike typical N-, P-, and O-based ligands, present the coordination sphere with a significant amount of steric and electronic mismatch, and (iii) the data support the fact that sulfoxides are moderate σ-donors and good-to-excellent π-acceptors – an aspect that should afford such metal chelates with a wide degree of reactivity. Finally, X-ray crystallographic experiments, coupled with an extensive CCDC search, provide an opportunity to establish the following ligand-ranking scheme for bidentate ligands spanned by an ethylene bridge, R2N–<RS(O)–<RS–<R2P–, based on the trans influence of chloride salts of Pt(II).

Synthesis and characterization of [Ga(TPP)H] (TPP=tetraphenylporphyrinato) by Yaoyu Feng; Say-Leong Ong; Jiangyong Hu; Wun-Jern Ng (466-468).
The synthesis, spectroscopic and structural characterization of the stable gallium hydride compound [Ga(TPP)H] (TPP=5,10,15,20-tetraphenylporphyrinato) have been reported. The hydride compound was synthesized in high yield (85%) by reducing [Ga(TPP)Cl] with sodium borohydride in N,N-dimethylformamide. The title compound was fully characterized by spectroscopic methods (IR, UV–Vis, and 1H NMR spectroscopy) and its molecular structure was established by X-ray crystallography. The Ga–H IR stretch occurs at 1864 cm−1, and the hydride 1H NMR resonance locates at −6.47 ppm. The gallium–hydrogen distance is 1.48(4) Å, whereas the gallium atom lies 0.46(1) Å from the perfect porphyrin plane.
Keywords: Gallium; Porphyrin; Hydride; Crystal structure;

Synthesis and crystal structure of photoluminescent copper(I)–phosphine complexes with oxygen and nitrogen donor ligands by Dan Li; Rong-Zhen Li; Zheng Ni; Zhi-Yu Qi; Xiao-Long Feng; Ji-Wen Cai (469-473).
Two mononuclear copper(I) complexes, [Cu(PPh3)2(oxine)](BF4) (1) and [Cu(PPh3)2(Quin)](BF4) (2), have been prepared and their structures determined by X-ray crystallography. In complex 1, the copper(I) is coordinated by two PPh3 groups and one neutral bidentate oxine (8-hydroxyquinoline) in a distorted tetrahedral geometry. The copper(I) atom in complex 2 is surrounded by two PPh3 and one quinoline (quin) to complete a three-coordinate environment. At room temperature in the solid state both complexes exhibit photoluminescence originated from the intraligand (oxine or quinoline) triplet enhanced by copper coordination. This may provide a new entry to develop new kinds of photoemissive materials.
Keywords: Copper(I) complex; Crystal structure; Oxine; Quinoline; Triphenylphosphine; Photoluminescence;

Polymeric nickel(II) and copper(II) complexes with btc2− ions as bridging ligands (btc2−=1,2,4,5-benzenetetracarboxylic acid dianion) by Ju Chang Kim; Hyejeong Jo; Alan J Lough; Jaeheung Cho; Uk Lee; Sang Yong Pyun (474-477).
Two new complexes of composition {[Ni( L )(btc 2−)]·2H 2 O}n (1) {L=1,4,8,11-tetraazacyclotetradecane} and {[Cu( L )(btc 2−)]·H 2 O}n (2) were obtained by reacting [Ni( L )]·2ClO 4 or [Cu( L )]·2ClO 4 and btc, and their structures were determined by analytical, spectroscopic, and X-ray diffraction methods. The blue complex 1 and violet complex 2 consist of 1D polymeric chains with nickel(II) or copper(II) macrocycles and bridging btc2− ligands, respectively. In 1 the COO groups on the 1,4-positions of the btc2− ligand are coordinated to the central nickel(II) atom, but in 2 the COOH groups on the 1,5-positions of the btc2− ligand are involved in interacting with the central copper(II) atom through an unusual carbonyl coordination.
Keywords: Nickel complex; Copper complex; Macrocyclic ligand complex; Benzenetetracarboxylic acid;

Di- and trinuclear Co(II) phenanthroline complexes of suberic acid (H2L): [Co2(phen)2(H2O)2L2]·5H2O and {Co[Co(phen)(H2O)4]2L4/2}L·4H2O.Reactions of phen and suberic acid (H2L) with fresh precipitated cobalt carbonate and cobalt hydroxide in EtOH/ H2O afforded [Co2(phen)2(H2O)2L2]·5H2O 1 and {Co[Co(phen)(H2O)4]2L4/2}L·4H2O 2, respectively. The basic building units are the centrosymmetric [Co2(phen)2(H2O)2L2] complex molecules in 1 and polymeric ∞ 1{Co[Co(phen)(H 2 O)4]2 L 4/2}2+ cationic chains in 2.[Co2(phen)2(H2O)2L2]·5H2O 1 and {Co[Co(phen)(H2O)4]2L4/2}L·4H2O 2 (H2L=suberic acid, HOOC–(CH2)6–COOH) were prepared by reaction of phenanthroline and suberic acid with freshly-precipitated CoCO3·xH2O and Co(OH)2·yH2O, respectively, in EtOH/ H2O. Compound 1 consists of the centrosymmetric dinuclear [Co2(phen)2(H2O)2L2] complex molecules and hydrogen bonded H2O molecules and the complex molecules are assembled via π–π stacking interactions and weak C–H⋯O hydrogen bonds to generate 2D layers, whose assembly based on O–H⋯O hydrogen bonds results in 3D framework with the crystal H2O molecules in tunnels. The crystal structure of 2 featured the polymeric ∞ 1{Co[Co(phen)(H 2 O)4]2 L 4/2}2+ cationic chains from bis-monodentate suberato ligands doubly bridging trinuclear {Co[Co(phen)(H2O)4]2}6+ units, in which the central Co atom is coordinated via μ 2-H2O molecules to two [Co(phen)(H2O)4]2+ complex ligands. Through π–π stacking interactions, the polymeric cationic chains are held together into 2D layers, which are further connected by suberate anions and lattice H2O molecules. The thermal and magnetic behavior of 1 and 2 is discussed.
Keywords: Cobalt; Suberato complexes; X-ray structures; Magnetic properties;

Ruthenium(II) complexes of the type [Ru(CO)(B)(L)] (B=AsPh3, pyridine, piperidine or morpholine; L=dianion of tetradentate Schiff bases) have been synthesized and characterized by physico-chemical methods. These complexes are found to be effective catalysts in the oxidation of primary and secondary alcohols using N-methylmorpholine-N-oxide as oxidant. The catalytic activity of these triphenylarsine complexes have been compared with that of triphenylphosphine complexes and with similar ruthenium(III) complexes. The formation of high valent Ru n+2O species as catalytic intermediate is proposed for the catalytic processes.
Keywords: Ruthenium(II) triphenylarsine complexes; Tetradentate Schiff bases; Catalytic oxidation study; Intermediate ruthenium-oxo species;

Two mononuclear Ag(I) complexes, [Ag(tbsb)](NO3)·DMF (1) and [Ag(tbsb)](NO3)·4.5H2O (2) {tbsb=1,3,5-tris(2-benzimidazol)sulfanylmethyl)-2,4,6-trimethylbenzene}, have been synthesized by self-assembly reaction of AgNO3 with tbsb and characterized structurally. The silver atoms of both the complexes are coordinated by the imine nitrogen atoms from a tripodal ligand (tbsb) to form two- and three-coordinate structures, respectively. Complex 1 presents the first example of silver (I) compound of the tripodal ligand possessing propeller-like structure.
Keywords: Tripodal ligand; Ag(I) complex; Crystal structure; Propeller;

A three-dimensional coordination framework containing μ4-sulfate anions [Cd(μ4-SO4)(bpy)] n (bpy=4,4-bipyridine) by Ying Xu; Wen-hua Bi; Xing Li; Dao-feng Sun; Rong Cao; Mao-chun Hong (495-497).
The reaction of 3CdSO4·8H2O with 4,4-bipyridine (bpy) in aqueous solution gives rise to a coordination polymer [Cd(μ4-SO4)(bpy)] n (1). X-ray single-crystal diffraction analyses reveal that the compound in space group P21212 creates a three-dimensional structure with unusual μ4-sulfate-bridges.A novel three-dimensional Cadmium(II) complex [Cd(μ4-SO4)(bpy)] n with μ4-sulfate anions was prepared and characterized by X-ray and fluorescent analysis.
Keywords: Cadmium complex; Coordination polymer; Crystal structure; Fluorescence; μ4-sulfate;

Theoretical and spectrophotometrical study of the interaction of nitric oxide with copper (II) dithiocarbamates by Alfredo Mederos; Agostinho Cachapa; Rita Hernández-Molina; Maria Teresa Armas; Pedro Gili; Maxim Sokolov; Javier González-Platas; Felipe Brito (498-502).
Potassium 1-[2-(2-hydroxyethoxy)ethyl]piperazinedithiocarbamate (1) and bis{1-[2-(2-hydroxyethoxy)ethyl]piperazinedithiocarbamato} copper(II) (2) were prepared for the first time. The crystal structure of (2) was determined by single crystal X-ray diffraction analysis. (2) is a centrosymmetrical molecule with a CuS4 “core” plane. Theoretical studies for the similar compound bis[1-(2-hydroxyethyl)piperazinedithiocarbamato] copper(II) (3), (3)NO, (3)(NO)(H2O) and (3) (NO)2 were carried out by means of the SPARTAN’02 program.The interaction of the previously prepared [Cu{S2CN(CH2CH2OH)2}2] (4) with nitric oxide in aqueous solution at pH 7.4 and 20 °C was spectrophotometrically studied, and the experimental data were analysed by means of the SPEFO-LETAGROP program. The formation constants of the complexes (4)(NO) and (4)(NO)2 were determined.
Keywords: Copper (II) dithiocarbamates; Crystal structure; Nitric oxide interaction; Molecular modelling; Stability constants; Speciation;

A tetranuclear oxomolybdenum(V) complex with bridging squarate ligands, [MoV 4O8(OH)2(H2O)2(C4O4)2]2− by Laurent Lisnard; Pierre Mialane; Anne Dolbecq; Jérôme Marrot; Francis Sécheresse (503-505).
The new tetranuclear polyoxomolybdate(V) ion [MoV 4O8(OH)2(H2O)2(C4O4)2]2− has been obtained in one step by the reaction of sodium molybdate, hydrazine and squaric acid in water and crystallized as a potassium salt. The structure has been solved by single-crystal X-ray diffraction showing the location of the hydroxo and water molecule ligands.
Keywords: Polyoxometalate; Squarate ligands; Crystal structure; Molybdenum;

The reaction of (PyH)2[MoOCl5] with pyridine and methanol in the presence of CoCl2·6H2O and H2C2O4·2H2O at 130 °C under solvatothermal conditions afforded (Me–NC5H5)4n [Mo8O26] n 1. The structure consists of infinite molybdenum oxide chains bearing a negative charge and N-methylpyridinium cations. Eight {MoO6} octahedra are arranged in an edge-sharing manner to form compact octamolybdate subunits which are connected through pairs of Mo–O–Mo bridges into extended one-dimensional arrays.
Keywords: Polyoxometalates; Octamolybdate; Polymeric structures; Solvatothermal synthesis; Crystal structure;

1D zigzag coordination polymer [Cu(tacn)(4,4-bipy)] n ·(ClO4)2n (tacn=1,4,7-triazacyclononane): structure, spectroscopic, and magnetic properties by Jing-Yuan Xu; Wen Gu; He-Dong Bian; Fang Bian; Shi-Ping Yan; Peng Cheng; Dai-Zheng Liao; Zong-Hui Jiang; Pan-Wen Shen (513-516).
A new one-dimensional coordination polymer, [Cu(tacn)(4,4-bipy)] n ·(ClO4)2n (tacn = 1,4,7-triazacyclononane, 4,4-bipy = 4,4-bipyridine), has been synthesized and characterized by X-ray crystallography, elemental analysis, IR, electronic spectra, ESR and variable-temperature magnetic susceptibility (4–300 K). The Cu(II) ion is five-coordinated in a distorted square-pyramidal environment to three nitrogens of tacn and two nitrogens from two 4,4-bipy ligands. Each 4,4-bipy, in which two pyridine rings are slightly twisted, links two [Cu(tacn)]2+ units to form 1D zigzag chain. The magnetic behavior shows very weak interaction between metal ions.A new one-dimensional coordination polymer, [Cu(tacn)(4,4-bipy)] n ·(ClO4)2n (tacn = 1,4,7-triazacyclononane, 4,4-bipy = 4,4-bipyridine), has been synthesized and characterized by X-ray crystallography, elemental analysis, IR, electronic spectra, ESR and variable-temperature magnetic susceptibility.
Keywords: Crystal structure; One-dimensional zigzag chain; 1,4,7-triazacyclononane; Copper(II) complex;

Reaction of Cp*TiMe(CF3SO3)(OAr) (2, OAr=O-2,6- i Pr 2 C 6 H 3 ) with 5-hexen-1-ol in n-hexane gave Cp*Ti(CF3SO3)[OCH2(CH2)3CHCH2](OAr) (3) exclusively (94% yield). 3 was very stable upon heating, and the structural analysis has been made by X-ray crystallography. Reaction of Cp*TiMe2(OAr) with both 5-hexen-1-ol and 3-buten-1-ol have also been explored.
Keywords: Titanium complex; Alken-1-ol; Half-titanocene; Olefin polymerization;

Effect of Al3+ on the photoluminescence properties of Ni2+-doped sol–gel SiO2 glass by Chun Feng Song; Meng Kai Lü; Feng Gu; Su Wen Liu; Shu Fen Wang; Dong Xu; Duo Rong Yuan (523-526).
Ni2+-doped SiO2, Al2O3–99SiO2 glasses have been prepared by sol–gel method. The effect of Al3+ on the photoluminescence (PL) properties of Ni2+-doped SiO2 has been studied. Ni2+-doped sol–gel SiO2 glass shows an emission band at 510 nm, which is attributed to the d–d transition 1 T 2(1 D)→3 A 2(3 F) of Ni2+ in octahedral sites. The emission of Ni2+ ions is greatly enhanced by the addition of Al3+ into SiO2. The study on Fourier transform infrared spectroscopy (FT-IR) and UV–Vis absorption spectra shows that the glass network and coordination environment of Ni2+ are changed after adding Al3+ into SiO2.
Keywords: Sol–gel method; Silica; Photoluminescence;

This paper describes the synthesis, characterization and crystal structure of an organic–inorganic polymeric hybrid composed of Ca, Na, and phosphocitrate (CaNaPC). CaNaPC is synthesized by reaction of CaCl2·2H2O and Na4(HPC)·3H2O in water, at pH 2. Its structure is polymeric with Ca(PC)2(H2O) “monomers” connected through Na+ bridges. The 9-coordinate Ca occupies the center of an irregular polyhedron defined by four phosphate, four carbonyl, and one H2O oxygens. CaO(C) distances are in the 2.446(2)–2.586(2) Å range. There is a short distance of 2.477(1) Å between Ca and the ester O from C–O–PO3H2. All –COOH groups are protonated. There are three dissociated protons per two PC molecules, all coming from –PO3H2. Na ions are six-coordinate surrounded by –COOH’s. The anticalcification properties of CaNaPC on plaque growth were studied in vivo using rats as model systems. Na–phosphocitrate is an effective inhibitor, but its effectiveness diminishes when a lower dose is used (9.7 mg as H5PC), resulting in only 30% plaque reduction. Superior inhibition activity becomes evident by following treatment with CaNaPC, at an equal dose (9.6 mg as H5PC) giving nearly quantitative (95%) plaque inhibition.
Keywords: Phosphocitrate; Biomineralization; Calcium phosphonates; Anticalcification; Crystal growth;

Cucurbit[6]uril as ligand for the complexation of lanthanide cations in aqueous solution by H.-J. Buschmann; K. Jansen; E. Schollmeyer (531-534).
The complex formation between lanthanide cations and the macrocyclic ligand cucurbit[6]uril has been studied in aqueous solution and in aqueous formic acid using different experimental techniques. With the exception of Nd3+ the stability constants of all complexes formed in aqueous formic acid are nearly identical. The values of the reaction enthalpies abruptly increase from a mean value of 1–3.4 kJ mol−1 going from Eu3+ to Gd3+. The values of the reaction entropies are nearly identical for all lanthanide cations. In pure aqueous solution a slight increase of the stability constants from La3+ to Lu3+ is observed.
Keywords: Cucurbituril; Lanthanide; Complexes; Calorimetry;

Three-Dimensional open-framework cobalt–molybdenum phosphate by hydrothermal synthesis: (C2H9N2)4(C2H10N2)[Co3Mo4P4O28] by Cheng-Ling Pan; Jiang-Feng Song; Ji-Qing Xu; Guang-Hua Li; Ling Ye; Tie-Gang Wang (535-538).
The new three-dimensional open-framework cobalt(II) molybdenum(VI) phosphate, (C2H9N2)4(C2H10N2)[Co3Mo4P4O28] 1, has been prepared by the reaction of sodium molybdate, phosphoric acid and ethylenediamine with Co2+ salts. The crystal data for 1 are as follows: Tetragonal, space group I4(1)/a, a=17.088(2) Å, c=10.745(2) Å V=3137.7(9)  A ̊ 3 , Z=4. The structure of 1 is constructed from CoMo2P tetrahedral units connected by CoO4 tetrahedra through sharing corners. The connectivity leads to the formation of intersecting channels in all three crystallographic directions, resembling an aluminosilicate zeolite, and the channels are filled with charge-compensating ethylenediamine ions.
Keywords: Three-dimensional; Cobalt–molybdenum phosphate; Crystal structure; Hydrothermal synthesis;

The hydrothermal reaction of CuSO4·5H2O, MoO3, 4,4-ditertbutyl-2,2-biyridine and H2O in the mole ratio 2:1.5:1:2500 yields [Cu 6(dtbbpy)6 Mo 7 O 26]2[Mo 8 O 26]·26H 2 O  ( 1 ·26H 2 O). The structure of 1 ·26H 2 O consists of discrete α-[Mo8O26]4− anions and [Cu6(dtbbpy)6Mo7O26]2+ cations. The polyoxocation is constructed of an equatorial ring of three edge-sharing {MoO6} octahedra, capped on one face by a {Mo3Cu3O6} ring of corner-sharing molybdenum tetrahedra and copper square pyramids, and on the second face by a {Cu3MoO4} unit.

The complex CuI(BTA)(hfac) with BTA=bis(trimethylsilyl)acetylene and hfac=1,1,1,5,5,5-hexa-fluoroacetylacetonate shows a longest-wavelength absorption at at λ max=324 nm (ε=5400  M −1   cm −1 ) which is assigned to a spin-allowed CuI→π* (BTA) metal-to-ligand charge transfer (MLCT) transition. The solid complex displays an emission at λ max=601 nm which is assumed to originate from the lowest-energy MLCT triplet. In solution MLCT excitation leads to the release of the acetylene with 6×10−4 at λ irr=333 nm.
Keywords: Electronic spectra; Luminescence; Charge transfer; Photochemistry; Copper complexes; Acetylene complexes;

By reaction of lead(II) nitrate with P,P -diphenylmethylenediphosphinic acid in water solution a new inorganic–organic hybrid of formula [Pb(CH2(P(Ph)O2)2)] has been synthesized and structurally characterized. The complex displays a polymeric columnar structure, the column being formed by two intersecting sinusoidal ribbons of lead(II) ions bridged by bifunctional phosphinate ligands. The intersections of the ribbons are constituted by dimeric units of pentacoordinated lead(II) ions.
Keywords: Inorganic–organic hybrids; Crystal structures; Polymeric complexes; Lead complexes;

Metallacarboranes as an anion and a cation in a single species: a unique example for ion pairs by Jianhui Wang; Shoujian Li; Chong Zheng; John A. Maguire; Narayan S. Hosmane (549-552).
The reaction of closo-exo-5,6-Na(THF)2-1-Na(THF)2-2,4-(SiMe3)2-2,4-C2B4H4 (1) with anhydrous NdCl3, in a molar ratio of 2:1, produced the full-sandwiched neodymacarborane, 2,2,4,4-(SiMe3)4-5,6-[(μ-H)2Na(THF)2]-1,1-commo-Nd(η5-2,4-C2B4H4)2 (2), as a yellow-green crystalline solid in 80% yield. Compound 2 was further reacted with NdCl3, in 3:1 molar ratio, in a solvent mixture of dry benzene and THF to produce, in 75% yield, the novel dimeric ion-pair, {[closo-1-Nd(μ-H)6-2,4-(SiMe3)2-2,4-C2B4H4]+[1,1-(THF)2-2,2,4,4-(SiMe3)4-5,5,6,6-(μ-H)4-1,1-commo-Nd(η5-2,4-C2B4H4)](C4H8O)(C6H6)2}2 (3), consisting of a half-sandwich cationic neodymacarborane that is coordinated to anionic full-sandwiched neodymacarborane. Thus, a dual role of metallacarboranes as both the cation and the anion in a single species has been exemplified.
Keywords: Metallacarborane; Ion pairs; Neodymacarborane; Sandwich; Half-sandwich; Lanthanacarborane;

The photolysis of gold azide complexes in CH3CN leads to the formation of colloidal gold and [AuI(CN)2]. The gold atoms which are initially formed do not only agglomerate to colloidal particles but also react with the solvent. It is suggested that CH3CN adds oxidatively to atomic gold and [AuI(CN)2] is generated in subsequent reactions.
Keywords: Electronic spectra; Photochemistry; Gold complexes; Gold atoms; Gold colloids;

Solvo-displacement route to ternary compounds Ag–M–S (M=Ga, Cu or Hg) by Mingwang Shao; Lingfen Kong; Bing Hu; Guihua Yu; Yitai Qian (555-557).
Ternary compounds AgGaS2, Cu0.8Ag1.2S and Ag2HgS2 were prepared at 200 °C via a solvo-displacement route. The products were characterized with X-ray powder diffraction patterns, X-ray photoelectron spectra and transmission electron microscope images. A possible formation mechanism of solvo-displacement reaction was proposed.
Keywords: Ternary compound; Solvo-displacement reaction; AgGaS2; Cu0.8Ag1.2S; Ag2HgS2;

First end-to-end thiocyanato chain containing 5-coordinate copper(II) ions by Patricia Gómez-Saiz; Javier Garcı́a-Tojal; Francisco J. Arnáiz; Miguel A. Maestro; Luis Lezama; Teófilo Rojo (558-560).
The synthesis and crystal structure of a new [{Cu(L)(NCS)2} n ] complex where L=(C8H8N4O)=2-methylamino-5-pyridin-2-yl-1,3,4-oxadiazole are reported. The structure is made up of 1D-chains containing monomeric copper(II) units linked by thiocyanato groups which act as end-to-end bridges. The metal ions show a 5-coordinate environment with a stereochemistry close to SP where the basal plane positions are occupied by the N-donor atoms of the bidentate L ligand, a bridging and a terminal thiocyanato group. The apical site is occupied by an S-donor atom from the neighbor molecule. The shortest copper⋯copper distances are 5.599(6) Å. A paramagnetic behavior is observed in this compound.
Keywords: Copper(II) complexes; Oxadiazole complexes; Thiocyanato complexes;

Platinum(IV) complex with pyridoxal semicarbazone by Nikola Ž Knežević; Vukadin M Leovac; Violeta S Jevtović; Sanja Grgurić-Šipka; Tibor J Sabo (561-564).
The synthesis and characterization of a new ligand and the first complex with semicarbazide based ligand coordinated to platinum(IV) ion are reported. The new ligand, pyridoxal semicarbazone (H2PxSC), and complex [Pt(HPxSC)Cl3] are characterized by elemental analysis, molar conductivity, infrared, electronic and 1 H NMR spectroscopy. The novel complex of platinum(IV) ion contains monoanionic, tridentate ONO ligand, and three chlorine ions.
Keywords: Platinum(IV); Pyridoxal semicarbazone; 1 H NMR spectroscopy; ONO system;

Synthesis and crystal structure of copper and gold complexes of 1,2,5-thiadiazole-3,4-dithiolate. Charge transfer salt with TTF by Dulce Simão; Helena Alves; Isabel C Santos; Vasco Gama; Manuel Almeida (565-568).
The M(tdas)2 complexes (tdas2−=1,2,5-thiadiazole-3,4-dithiolate) with M=CuII, CuIII and AuIII were obtained as tetrabuthylammonium and tetraphenilphosphonium salts and characterised. The crystal structure of (n-Bu4N)n[M(tdas)2], M=Cu(2) and Au(4) were determined by X-ray crystallography as well as that of the charge transfer salt (TTF)2[Au(tdas)2]2 (5).
Keywords: Gold complex; Copper complex; S-ligands; Cyclic voltammetry; X-ray crystallography;

Corundum-type indium (III) oxide: formation under ambient conditions in Fe2O3–In2O3 system by Alexander Gurlo; Maria Ivanovskaya; Nicolae Barsan; Udo Weimar (569-572).
The influence of the iron doping on the structural transformations in In2O3 has been studied. The samples were prepared by the sol–gel technique via coprecipitation from the solution of In(III) and Fe(II) salts. For the first time, the formation of corundum-type In2O3 under ambient conditions in iron-doped In2O3 samples was observed.
Keywords: In2O3; Fe2O3; Corundum structure; Sol–gel process;

Synthesis, structure and properties of terephthalate-bridged copper (II) polymeric complex with zigzag chain by He-Dong Bian; Jing-Yuan Xu; Wen Gu; Shi-Ping Yan; Dai-Zheng Liao; Zong-Hui Jiang; Peng Cheng (573-576).
The complex, {[Cu L(μ 2 -ta)](CH 3 OH)2}n (L=N,N-dimethyl-N -(pyrid-2-ylmethyl)-ethylene-diamine, ta=terephthalic acid dianion), has been synthesized. X-ray analyses revealed that the copper atom exhibits a distorted square pyramidal geometry, with three nitrogen atoms from the tridentate ligand and two carboxylato-oxygen atoms from different tas. Each ta ligand adopts a μ2-bridging mode with a typical average Cu–O distance (1.945–2.204 Å), and the tridentate ligand acts as a terminal ligand with a typical Cu–N distance (1.992–2.087 Å). Thus, each ta ligand links two metal centers and each metal center connects two ta ligands to form the zigzag chain structure. Variable temperature magnetic measurement of the complex shows that a weak ferromagnetic interaction between the copper(II) ions.The complex, {[Cu L(μ 2 -ta)](CH 3 OH)2}n (L=N,N-dimethyl-N -(pyrid-2-ylmethyl)-ethylene-diamine, ta=terephthalic acid dianion), has been synthesized. In the complex, each ta ligand links two metal centers and each metal center connects two ta ligands to form the zigzag chain structure.
Keywords: Terephthalate-bridged; Copper complex; Crystal structure; Zigzag chain;

Treatment of Pd(PPh3)4 with Me2NC(S)Cl in dichloromethane at −20 °C produces the complex [Pd(PPh3)21-SCNMe2)(Cl)], 2. Variable temperature 1H and 31P{H} NMR experiments of complex 2 shows the dissociation of either the chloride or the triphenylphosphine ligand to form complex [Pd(PPh3)22-SCNMe2)][Cl], 3 or the dipalladium complex [Pd(PPh3)Cl]2(μ,η2-SCNMe2)2, 4. The reaction of complex 2 with NaPF6 affords complex [Pd(PPh3)22-SCNMe2)][PF6], 5. Complexes 2, 4, and 5 are characterized by X-ray diffraction analyses.
Keywords: Dissociation behaviour; N,N-dimethylthiocarbamoyl; Palladium; Sulfur-assisted; X-ray diffraction;

Barium sulfonate [Ba2L4(H2O)10] (HL=3-carboxy-4-hydroxybenzenesulfonic acid) was obtained by the reaction of BaCl2·2H2O with NaL in water. X-ray structural analysis reveals that the compound has an undulating ladder structure which is the first ladder structure containing three different kinds of squares.
Keywords: Barium; Sulfonate; Coordination polymer; Ladder structure;

The first examples of uncharged aryl substituted fluorinated hydridophosphazenes, N3P3F4(Ar)H [Ar=C6H5 (1), p-ClC6H4 (2)] were obtained in an unprecedented manner upon fluorination of diaryloctachlorobi(cyclophosphazenes) (N6P6Cl8(Ar)2) [Ar=C6H5, p-ClC6H4] using KF in acetonitrile. The compounds (1) and (2) were stable to air and moisture, and were characterized by spectral and analytical methods. Compound (1) on reaction with FcCH2P(S)(CH2OLi)2 (Fc=Ferrocenyl) gave endo (3) and exo (4) isomers of ansa substituted hydridophosphazenes. The crystal structure of (4) was determined and the structure shows the ansa substitution on the phosphazene ring, trans to the phenyl group with the hydridophosphazene ring puckered to a partial chair configuration.
Keywords: Hydridophosphazene; Fluorinated; Ansa; Ferrocene; p-Chlorophenyl; Fluorophosphazene;

Hydrothermal reaction of VOPO4·2H2O and [Co(en)3]Cl3 in sealed borosilicate glass tube yielded a vanadium (V) borophosphate cluster based solid, [Co(en)3][enH2]{V3BP3O19}·4.5H2O (VBPO). Crystal data: monoclinic space group, P21/c, Z=4, a=12.0709(7), b=14.2261(8) and c=18.1104(9) Å, β=95.067(1)0°, V=3097.8(3)  A ̊ 3 . Single crystal X-ray diffraction studies revealed that discrete [V3BP3O19] clusters are linked to counter cations and water molecules through a complex hydrogen bonding network.
Keywords: Hydrothermal synthesis; Vanadium borophosphate; Single crystal X-ray diffraction;

Di-μ-hydroxy macrocyclic ytterbium(III) complex by Jerzy Lisowski; Przemysław Starynowicz (593-597).
The mononuclear [YbracL]Cl3·2H2O and dinuclear [Yb2(OH)2Cl2(racL)2]Cl2·4CH3OH·2H2O complexes of the macrocyclic ligand L derived from trans-1,2-diaminocyclohexane and 2,6-diformylpyridine have been obtained. The formation of the dinuclear species upon addition of hydroxide to the [YbracL]Cl3·2H2O or the enantiopure [YbrrrrL(NO3)2](NO3) has been followed using 1H NMR spectroscopy. The X-ray crystal structure of [Yb2(OH)2Cl2(racL)2]Cl2·4CH3OH·2H2O complex has been determined. The complex is a dimer consisting of two macrocyclic units. The Yb(III) ion is coordinated by six nitrogen atoms of the macrocyclic ligand, two bridging OH groups and chloride anions. The chiral macrocycle L in this complex exhibits twist-bent conformation of approximate C2 symmetry.
Keywords: Chiral macrocycles; Lanthanide complexes; Hydroxo complexes; Crystal structure;

The structures and decomposition products of palladium(II) and platinum(II) terpyridine phenoxide complexes by Xiaoming Liu; Sylvie L Renard; Colin A Kilner; Malcolm A Halcrow (598-603).
A series of complexes of formula [Pd(OR)(terpy)]BF4 and [Pt(OR)(terpy)]BF4 (ROH=a substituted phenol; terpy=2,2:6,2-terpyridine) have been prepared by reaction of [M(OH)(terpy)]BF4 (M=Pd, Pt) with ROH. One Pd(II) and one Pt(II) complex in this series have been structurally characterised. These compounds are very acid sensitive; decomposition products resulting from recrystallisation of two of these compounds from MeNO2 or MeCN have been crystallographically characterised.
Keywords: Palladium complexes; Platinum complexes; Phenoxide complexes; Crystal structure;

Biological and medicinal aspects of vanadium by Dieter Rehder (604-617).
The importance of vanadium in life processes is addressed, emphasising the vanadium cofactors in vanadate-dependent haloperoxidases and vanadium-nitrogenases. Structural and functional model compounds for these enzymes are introduced, and the use of haloperoxidase models in the enantioselective oxygenation of thioethers is discussed. Specific attention is given to the redox interaction on the one hand, and stabilisation by coordination on the other hand, in the systems vanadium(III, IV and V) plus (bio-related) thiofunctional compounds, since these interactions should be of some importance in vanadium speciation under physiological conditions. With respect to the medicinal potential of vanadium compounds, their insulin-mimetic behaviour and hence efficacy in the oral treatment of both forms of diabetes mellitus is extemporated.
Keywords: Vanadium; Haloperoxidases; Nitrogenases; Insulin-mimetic behaviour; Thiofunctional Ligands;