Inorganic Chemistry Communications (v.13, #6)

Contents List (iii-x).

Three new interesting coordination polymers, [Zn(PDCO)(H2O)·H2O]n (1), [Co(PDCO)(H2O)3]n (2) and [Mn(PDCO)(H2O)2]n (3), (H2PDCO = pyridine-2,4-dicarboxylic acid N-oxide), have been prepared under hydrothermal conditions and structurally characterized. Polymer 1 exhibits 0D Zn units, polymer 2 features 1D infinite zigzag Co chains. In polymer 3, four Mn atoms and four PDCO ligands form a 24-member ring and these rings are interlocked to form a 2D infinite layer. Compounds 1–3, with systematic variation in dimensionality from 0D to 1D to 2D, are the first examples of metal coordination polymers into which pyridine-2,4-dicarboxylic acid N-oxide has been introduced. In addition, the photoluminescent properties of 1 as well as the magnetic behavior of 2 have been investigated.Three new interesting coordination polymers, [Zn(PDCO)(H2O)·H2O]n (1), [Co(PDCO)(H2O)3]n (2) and [Mn(PDCO)(H2O)2]n (3), (H2PDCO = pyridine-2,4-dicarboxylic acid N-oxide), have been prepared under hydrothermal conditions and structurally characterized. Polymer 1 exhibits 0D Zn units, polymer 2 features 1D infinite zigzag Co chains. In polymer 3, four Mn atoms and four PDCO ligands form a 24-member ring and these rings are interlocked to form a 2D infinite layer. Compounds 1–3, with systematic variation in dimensionality from 0D to 1D to 2D, are the first examples of metal coordination polymers into which pyridine-2,4-dicarboxylic acid N-oxide has been introduced. In addition, the photoluminescent properties of 1 as well as the magnetic behavior of 2 have been investigated.Display Omitted
Keywords: Pyridine-2,4-dicarboxylic acid N-oxide; Coordination polymer; Weak interactions; Luminescence; Magnetic property;

New hetero-dilanthanide β-diketonate complexes of the type [Ln1Ln2(fod)6(μ-bpm)] {fod is the anion of 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione; bpm = 2,2′-bipyrimidine; Ln1  = Pr and Ln2  = Nd (1); Ln1  = Nd and Ln2  = Sm (2); Ln1  = Eu and Ln2  = Tb (3) and Ln1  = Ho and Ln2  = Er (4)} have been isolated by reacting sequentially, the coordinatively unsaturated Ln(fod)3 chelates of two different lanthanides and 2,2′-bipyrimidine bridging ligand in 1:1:1 molar ratio, in ethanol. The purity and hetero-dilanthanide nature of the complexes has been confirmed by NMR, 4f–4f absorption spectroscopies and electrospray mass spectrometry. The oscillator strength of the hypersensitive transitions confirms the presence of the two different lanthanides in the complexes in 1:1 ratio. The complexes 2 and 3 display strong pink and red luminescences, respectively. The intramolecular Tb(III) → Eu(III) energy transfer has been observed in complex 3.Display OmittedNew hetero-dilanthanide β-diketonate complexes of the type [Ln1Ln2(fod)6(μ-bpm)] {fod is the anion of 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione; bpm  =  2,2′-bipyrimidine; Ln1=  Pr and Ln2=  Nd (1); Ln1=  Nd and Ln2=  Sm (2); Ln1=  Eu and Ln2=  Tb (3) and Ln1=  Ho and Ln2=  Er (4)} have been isolated by reacting sequentially, the coordinatively unsaturated Ln(fod)3 chelates of two different lanthanides and 2,2′-bipyrimidine bridging ligand in 1:1:1 molar ratio, in ethanol. The complexes 2 and 3 display strong pink and red luminescences, respectively. The intramolecular Tb(III)   Eu(III) energy transfer has been observed in complex 3.
Keywords: Hetero-dilanthanide complex; NMR; 4f–4f absorption; Tb(III) → Eu(III) energy transfer; Luminescence;

Assembly of two ferrous coordination polymers with triazole derivative: Syntheses, structures and magnetic properties by Yao Chen; Shi-Yuan Zhang; Xiao-Qing Zhao; Jing-Jing Zhang; Wei Shi; Peng Cheng (699-702).
The reactions of Fe(II) salts with 1,4-bis(1,2,4-triazole-1-ylmethyl-benzene) (btx) give two new Fe(II) coordination polymers {[Fe(btx)3](ClO4)2}n (1) and {[Fe(btx)(SO4)(H2O)2]}n (2), which have been characterized by element analysis, PXRD, single-crystal X-ray diffraction and magnetic susceptibility. 1 shows infinite plait-like chain structure, while 2 exhibits as 2D grid. Magnetic studies indicate that the Fe(II) ions in the two coordination polymers retain in high-spin ground state upon cooling from 300 to 2 K, showing antiferromagnetic interactions.Display OmittedThe reactions of Fe(II) salts with 1,4-bis(1,2,4-triazole-1-ylmethyl-benzene) (btx) give two new Fe(II) coordination polymers {[Fe(btx)3](ClO4)2}n (1) and {[Fe(btx)(SO4)(H2O)2]}n (2), which have been characterized by element analysis, PXRD, single-crystal X-ray diffraction and magnetic susceptibility. 1 shows infinite plait-like chain structure, while 2 exhibits as 2D grid. Magnetic studies indicate that the Fe(II) ions in the two coordination polymers retain in high-spin ground state upon cooling from 300 to 2 K, showing antiferromagnetic interactions.
Keywords: Crystal structure; Fe(II) complex; Coordination polymer; Magnetic property;

Hydrothermal synthesis and characterizations of a novel metal coordination fragment derivative of polyoxotungstate by Yan Wang; Feng-Qing Wu; Ling Ye; Tie-Gang Wang; Guo-Wu Wang; Shu-Yun Shi; Li-Na Xiao; Xiao-Bing Cui; Ji-Qing Xu (703-705).
A novel polyoxometalate [PW11O39Ni(4,4′-Hbpy)]·(4,4′-H2bpy)2·3H2O (1) has been hydrothermally synthesized and characterized by IR, XPS, TG, elemental analysis and single-crystal X-ray diffraction analysis. Crystal structure analysis reveals that 1 is a novel metal coordination fragment derivative of the classic Keggin polyanion.A novel metal coordination fragment derivative of the classic Keggin polyanion has been hydrothermally synthesized and characterized by IR, XPS, TG, elemental analysis and single-crystal X-ray diffraction analysis.Display Omitted
Keywords: Polyoxometalate; Substituted; Hydrothermal synthesis; Metal-nitrido derivative; Lacunary polyanion;

Two coordination polymers, namely, [Co(IM)6][Co2(SIP)3] (1) (IM = imidazole, H3SIP = 5-sulfoisophthalic acid) and [BMIM]2[Cd2(SIP)3] (2) (BMIM = 1-n-butyl-3-methylimidazolium) were synthesized in ionothermal reactions by using ionic liquid 1-n-butyl-3-methylimidazolium tetrafluoroborate as solvent. Single-crystal X-ray analyses revealed that 1 has an anionic 1D polymeric chain charge balanced by an uncommon [Co(IM)6]2+ cation. Complex 2 features an anionic 2D layer containing unique tetranuclear [Cd4(CO2)6(SO3)2] cluster wherein the four Cd atoms are co-planar. The imidazolium cation [BMIM]+ of the ionic liquid acting as charge compensating agent intercalated into the [Cd2(SIP)2]2n interlayers in structure 2. The rich ionic environments of the ionic liquid may be particularly helpful in the formation of the anionic frameworks of 1 and 2.Two coordination polymers, [Co(IM)6][Co2(SIP)3] (1) and [BMIM]2[Cd2(SIP)3] (2) were synthesized by using ionic liquids 1-n-butyl-3-methylimidazolium tetrafluoroborate as a solvent.Compound 1 has an anionic 1D polymeric chain charge balanced by an uncommon [Co(IM)6]2+ cation, and 2 features an anionic 2D layer containing unique tetranuclear [Cd4(CO2)6(SO3)2] cluster with charge compensating agent of [BMIM]+.Display Omitted
Keywords: Ionothermal; 1-n-Butyl-3-methylimidazolium tetrafluoroborate; Ionic liquid; Crystal structures;

Studies on thermodynamic nature of steroselectivity for ruthenium(II) polypyridyl complex binding to DNA by Hong Xu; Qian-Qian Zhu; Jun Lu; Xiao-Juan Chen; Jie Xiao; Zhi-Gang Liu; Si-Ping Chen; Ming-Liang Tong; Liang-Nian Ji; Yi Liang (711-714).
A pair of ruthenium(II) complex isomers, Δ- and Λ-[Ru(bpy)2(p-mpip)]2+ {bpy = 2,2′-bipyridine, p-mpip = 2-(4-methylphenyl)imidazo[4,5-f]1,10-phenanthroline} have been synthesized and characterized. Thermodyanmics of binding of the two isomers to calf thymus DNA (CT DNA) has been investigated by isothermal titration calorimetry (ITC). It is rare that the Λ isomer binds to DNA more strongly than the Δ isomer, which has been verified by viscosity measurements, and can be explained by their different thermodynamic driving forces of DNA binding for the first time. This suggests that the dominant factor governing the stereoselectivity of DNA binding of metal complex may be the different thermodynamic driving forces between interactions of its different isomer with DNA. This new finding may be very helpful to understand the nature of steroselective DNA binding of small chiral molecules, and be useful to the development of DNA molecular probes and new DNA targeting therapeutic drugs.Thermodynamic driving force has been used to explain an unusual stereoselectivity, in which the Λ isomer of Ru(II) complex binds to DNA more strongly than its Δ isomer.Display Omitted
Keywords: DNA; Ruthenium(II) complexes; Stereoselectivity; Thermodynamics; Isothermal titration calorimetry (ITC); Isomer;

Two novel cadmium(II) coordination polymers based on bis-functionalized ligand 4′-(4-carboxyphenyl)-2, 2′:6′, 2″-terpyridine by Qing-Ran Wu; Ji-Jiang Wang; Huai-Ming Hu; Bao-Cheng Wang; Xing-Long Wu; Feng Fu; Dong-Sheng Li; Meng-Lin Yang; Gang-Lin Xue (715-719).
Two novel cadmium(II) coordination polymers [Cd(cptpy)2] n ·nH2O (1) with a 1D double chain structure and [Cd2(cptpy)2(ox)] n ·2.5nH2O (2) with an interesting 3-connected uninodal six-fold interpenetrating ths network (Hcptpy = 4′-(4-carboxyphenyl)-2,2′:6′,2″-terpyridine, H2ox = oxalic acid) have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, single crystal X-ray diffraction and fluorescence spectra.Two novel cadmium(II) coordination polymers [Cd(cptpy)2] n ·nH2O (1) with a 1D double chain structure and [Cd2(cptpy)2(ox)] n ·2.5nH2O (2) with an interesting 3-connected uninodal six-fold interpenetrating this network have been synthesized under hydrothermal conditions and characterized.Display Omitted
Keywords: MOFs; 4′-(4-carboxyphenyl)-2,2′:6′,2″-terpyridine; Crystal structure; Fluorescent properties;

Synthesis, structure and properties of a new copper (II) complex, [Cu2(4,4′-bpy)5(H2O)4](ClO4)4(4,4′-bpy)(DMF)2(H2O)2 by Feilong Hu; Xianhong Yin; Yan Mi; Wanshu Li; Xinping Tang; Zhen Ma (720-723).
A new copper (II) complex with formula [Cu2(4,4′-bpy)5(H2O)4](ClO4)4(4,4′-bpy)(DMF)2(H2O)2 has been synthesized by reaction of 4,4′-bpyridine (4,4′-bpy) with Cu(ClO4)2. 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, anion⋯π and C–H⋯π interactions are also evident in the structure. The preliminary investigation on the thermal property of the complex is presented.Various solvent and anions (H2O, ClO4 , DMF, 4,4′-bpy) were encapsulates inside the channels (channel a, b, c and d) of the 3D networks which act as a host to stabilize the structure.Display Omitted
Keywords: Copper (II) complex; Water chain; Crystal structure; C–H⋯π;

Electrochemical- and chemical-induced variation of the metal oxidation state of ternary Os(II) polypyridyl complexes triggers reversible changes in optical properties. This read/write process can be carried out conveniently and monitored with optical (UV/Vis or luminescence) spectrophotometers. An excellent sensitivity and reversibility may make it a suitable candidate for integration of molecular sensors and logic gate system.Display OmittedElectrochemical- and chemical-induced variation of the metal oxidation state of ternary Os(II) polypyridyl complexes triggers a reversible changes in optical properties.
Keywords: Molecular switch; Logic gate; Sensor; Ternary complexes; Osmium;

Evaluation of the antioxidant, DNA interaction and tumor cell cytotoxicity activities of Copper(II) complexes with Paeonol Schiff-base by Dong-Dong Qin; Zheng-Yin Yang; Fu-Hong Zhang; Bo Du; Ping Wang; Tian-Rong Li (727-729).
Herein, we report for the first time on the preparation of four Paeonol Schiff-base ligands: 1,2-Bis(2-hydroxy-4-methoxy-α-methylbenzylideneimino) ethane (H2L1), 2-hydroxy-4-methoxy-α-methylbenzylidene (benzoyl) hydrazone (HL2), 2-hydroxy-4-methoxyacetophenone-ethanolamine Schiff-base (HL3), and 2-hydroxy-4-methoxyacetophenone(2′-hydroxybenzoyl) hydrazone (H2L4), and their Cu(II) complexes, of which the structure of C11N2O6H14Cu(CuL3.NO3) was confirmed by X-ray diffraction. Antioxidant activities of four Cu(II) complexes were studied by the standard non-enzymatic NBT method and Fenton system, used to produce superoxide anion radicals and hydroxyl radicals, respectively. The results show these Cu(II) complexes have excellent antioxidant activities. DNA-binding and in vitro cytotoxicity experiments were utilized to further investigate the biological activities of C11N2O6H14Cu(CuL3.NO3). These results support C11N2O6H14Cu as a potential candidate for biological use because it shows not only high antioxidant and moderate DNA-binding activities, but also good tumor cell cytotoxicity activities in human cell lines carcinomas Hep-2 (larynx), for the range of concentrations tested.Biological activities of copper (II) complexes with four different Paeonol-based Schiff-base ligands were intensively evaluated.Display Omitted
Keywords: Antioxidant; DNA-binding; Cytotoxicity; Paeonol; Crystal structure;

Synthesis and characterization of a new 2D trimetallic Mn/Ca/Na complex by Na Li; Mei Wang; Cheng-Bing Ma; Ming-Qiang Hu; Rong-Wei Zhou; Hui Chen; Chang-Neng Chen (730-732).
A new tri-metallic Mn/Ca/Na coordination polymer, {[Mn3NaCa(sal)6(H2O)6]·7H2O} n (1·7H2O), has been synthesized and characterized by single crystal X-ray diffraction, IR spectroscopy, and magnetic measurements. The X-ray analysis shows 1 consists of a 2D homochiral (6,3) network with chiral [Mn3Na] clusters and chiral Ca ions as alternating nodes. Magnetic property study reveals the existence of weak antiferromagnetic couplings between Mn(III) ions with the interaction parameter J being − 0.438 cm− 1 within the complex. Display OmittedA new tri-metallic Mn/Ca/Na coordination polymer, {[Mn3NaCa(sal)6(H2O)6]·7H2O} n (1·7H2O), has been synthesized and characterized by single crystal X-ray diffraction, IR spectroscopy, and magnetic measurements. The X-ray analysis shows 1 consists of a 2D homochiral (6,3) network with chiral [Mn3Na] clusters and chiral Ca ions as alternating nodes. Magnetic property study reveals the existence of weak antiferromagnetic couplings between Mn(III) ions with the interaction parameter J being − 0.438 cm− 1 within the complex.
Keywords: Salicylic ligand; Coordination polymer; Mn/Ca cluster; Oxygen-evolving complex; Magnetic property;

Two coordination polymers with the same mixed ligands but different metal ion, [Cd5(bpp)6(μ 1,1-N3)6(μ 2-Cl)2Cl2]n (1) and {[Ni2(bpp)4(N3)4]·0.5H2O}n (2) (bpp = 1,3-bis(4-pyridyl)propane), have been hydrothermally synthesized and fully structural characterized. Complex 1 exhibits an eight-connected bcu-type 3D framework with end-on azido-aggregated neutral pentanuclear clusters periodically extended by neutral bpp linkers. Instead, 2 reveals an interpenetrated 2D (4, 4) undulated layer assembled from the octahedral Ni(II) nodes and bridging bpp connectors with monodentate azide anions terminally attached on both sides. Additionally, in contrast to non-fluorescent 2, solid complex 1 displays an intense luminescent emission resulted from the ligand-to-metal charge-transfer upon the cation binding.Display Omitted
Keywords: Metal-organic framework; Neutral pentanuclear cluster; 1,3-bis(pyridyl)propane; Secondary building units; Two-fold interpenetration;

Two new coordination polymers, [Co2(L)1.5(OH)(H2O)2]·2H2O (1) and [CoL(bpp)] (2) (H2L = 2,5-dibenzoylterephthalic acid and bpp = 1,3-bis(4-pyridyl)propane), have been synthesized and characterized by elemental analyses, IR spectra, and thermogravimetric analyses. Their structures were determined by single crystal X-ray diffraction analyses. Complex 1 exhibits a 3D framework assembled from tetra-nuclear cobalt-oxygen bridged by carboxylic O atoms with a (412·63) topology. Complex 2 possesses a 2D layered structure which extends into a 3D architecture via C–H···π interaction between propane proton and the phenyl ring or pyridine ring of an adjacent sheets. Furthermore, the magnetic properties of them are discussed.Two new coordination polymers, [Co2(L)1.5(OH)(H2O)2]·2H2O (1) and [CoL (bpp)] (2) (H2L1  = 2,5-dibenzoylterephthalic acid and bpp = 1,3-bis(4-pyridyl)propane), have been synthesized. Complex 1 exhibits a 3D framework assembled from tetranuclear cobalt-oxygen bridged by carboxylic O atoms with a (412·63) topology. 2 possesses a 2D layered structure which extends into a 3D architecture via C–H···π interaction.Display Omitted
Keywords: Cobalt complexes; Carboxylate ligand; Crystal structure; Magnetic properties;

Reaction of [Ru(bpym)3]2+ (bpym = 2,2′-bipyridmidine) with hexacyanoruthenate under forcing conditions affords a mixture of the trinuclear species [(bpym)Ru{(µ-bpym)Ru(CN)4}2]2 , [1]2 , and the tetranuclear species [Ru{(µ-bpym)Ru(CN)4}3]4 , [2]4 , in which two or three (respectively) of the peripheral vacant bpym binding sites of [Ru(bpym)3]2+ are occupied by {Ru(CN)4}2 fragments. Thus, [1]2 and [2]4 have eight and twelve externally-directed cyanide groups respectively for use in forming high connectivity coordination networks. The crystal structure of HK[1]·2MeOH·6.5H2O reveals a one-dimensional ladder structure in which [1]2 anions are connected by (i) cyanide/K+ and (ii) bpym/K+ coordination interactions.Reaction of [Ru(bpym)3]2+ (bpym = 2,2′-bipyrimidine) with K4Ru(CN)6 results in the attachment of {Ru(CN)4}2 fragments at two or three of the peripheral vacant diimine sites, giving trinuclear [1]2 (with eight externally-directed cyanide ligands) and tetranuclear [2]4 (with 12 externally-directed cyanides in a D 3 symmetric array). These are interesting building blocks for crystal engineering applications providing potentially very high connectivity at a single node in cyanide-bridged networks.Display Omitted

A new bitrack sinusoid-like chain templated by Wells–Dawson type polyoxometalate by Xiuli Wang; Hailiang Hu; Aixiang Tian; Hongyan Lin; Jin Li; Limin Shi (745-748).
A new Wells–Dawson type polyoxometalate (POM)-templated compound, [Cu42-O)2(4,4′-bpo)4(INA)2(H2O)4][(P2W18O62)]·H2O (1) (4,4′-bpo = 2,5-bis(4-pyridyl)-1,3,4-oxadiazole; INA = pyridine-4-carboxylic acid), has been hydrothermally synthesized. Compound 1 contains a novel bitrack sinusoid-like chain constructed from alternating dicopper units and non-linear rigid 4,4′-bpo linkers. Induced by POM templates, the adjacent chains formed elliptical spaces to accommodate the Wells–Dawson type anions.Through introducing a non-linear rigid ligand 4,4'-bpo and a small bridging ligand INA into the POMs system, a new Wells-Dawson type P2W18O626−-templated inorganic–organic hybrid compound has been hydrothermally synthesized and structurally characterized.Display Omitted
Keywords: Wells–Dawson Polyoxometalate; Inorganic-organic hybrids; Template synthesis; Electrochemical property;

Construction of two mercury(II) coordination frameworks involving in situ tetrazole ligand synthesis by Yongcai Qiu; Biao Liu; Guo Peng; Jinbiao Cai; Hong Deng; Matthias Zeller (749-752).
Two novel mercury(II)-organic polymeric complexes [HgCl(pzta)] n (1) and [Hg3Cl2(pzta)4(H2O)2] n (2) [pzta = pyrazinyl tetrazolate] were obtained by in situ synthesis of pyrazinyl tetrazolate from the reaction of pyrazinecarbonitrile with sodium azide in the presence of mercury(II) salts. Complex 1 is a 3D coordination polymer with a 3,5-connected hms [(63)(69  · 8)] net consisting of mildly undulate (6, 3) sheets and bridging chlorine ligands; while complex 2 is also a 3D supramolecular network built from 2D layers with the 4-connected sql {44  · 62} net that are assembled via hydrogen bonds and π⋯π stacking interactions. Last but not least, photofluorescent properties of the two complexes have also been investigated.Two novel mercury(II)-organic polymeric complexes [HgCl(pzta)] n (1) and [Hg3Cl2(pzta)4(H2O)2] n (2) [pzta = pyrazinyl tetrazolate] were obtained by in situ synthesis of pyrazinyl tetrazolate from the reaction of pyrazinecarbonitrile with sodium azide in the presence of mercury(II) salts.Display Omitted
Keywords: Mercury(II) complexes; In situ tetrazole synthesis; π⋯π stacking interaction; Fluorescence;

Two isomers containing a [Cu(Me2bpzb)] unit: Molecule (0-D) and 1-D by Young Joo Song; Ju Hoon Lee; Hyo Geun Koo; Tae Geum Lee; Sung-Hyun Myoung; Cheal Kim; Sung-Jin Kim; Youngmee Kim (753-756).
Two isomers (molecule 1 and 1-D 2) containing [Cu(Me2bpzb)] units have been obtained under the different reaction conditions, and their structures have been determined by X-ray crystallography. From the temperature-dependent magnetic data for 2, there was no interaction between Cu2+ ions through the ligand. The photoluminescence of the free H2Me2bpzb molecule displayed an intense emission band centered at about 482 nm, while complexes 1 and 2 exhibited no obvious emission bands.Two isomers (mononuclear and polymeric complexes) containing [Cu(Me2bpzb)] units have been obtained under the different reaction conditions, and their structures have been determined by X-ray crystallography. Their physical properties including magnetic susceptibility and photoluminescence have been studied and a mild catalytic system for the aerobic alcohol oxidation has been also developed.Display Omitted
Keywords: Copper complexes; One-dimensional chain; Magnetic susceptibility; Photoluminescence; Isomers;

A new family of trinuclear Ru(II) polypyridyl complexes acting as pH-induced fluorescence switch by Feixiang Cheng; Ning Tang; Jishu Chen; Fan Wang; Longhai Chen (757-761).
Tripodal ligands 1,3,5-tris{4-((1,10-phenanthroline-[5,6-d]imidazol-2-yl)phenoxy)methyl}-2,4,6-trimethylbenzene (L1), 1,1,1-tris{4-((1,10-phenanthroline-[5,6-d]imidazol-2-yl)phenoxy)methyl}propane (L2), 2,2′,2′′-tris{4-((1,10-phenanthroline-[5,6-d]imidazol-2-yl)phenoxy)ethyl}amine (L3), and corresponding Ru(II) complexes [(bpy)6L1–3(RuII)3](PF6)6, shortly called (Ru–L1–3), have been synthesized. UV–vis absorption and fluorescence spectra of these complexes are both strongly dependent on the pH of the buffer solution. These complexes act as pH-induced off–on–off fluorescence switch through protonation and deprotonation of the imidazole-containing ligands.A new family of Ru(II) polypyridyl complexes with imidazole fragments uncoordinated to the metal ion center has been synthesized. These complexes act as pH-induced off–on–off fluorescence switch through protonation and deprotonation of the imidazole-containing ligands.Display Omitted
Keywords: Trinuclear Ru(II) complex; pH switch; UV–vis absorption; Fluorescence;

Three-dimensional microporous metal–organic framework constructed from Cadmium(II) ion with terephthalate and in-situ generated amino-tetrazole mixed-ligands by DongSheng Liu; Yan Sui; ChangCang Huang; TongHen Pan; XiHe Huang; JianZhong Chen; XiaoZeng You (762-765).
A new coordination polymer, [Cd4(atz)6(PTA)] n has been firstly synthesized by employing mixed-ligand of terephthalic acid (PTA) with the in-situ generated ligand of 5-amino-tetrazolate (atz). Compound 1 represents a 3D microporous framework constructed from Cd-tetrazolate subunits and the subunits are bridged by PTA and atz ligands. When the subunit was collided into node, compound 1 possesses an unprecedented 3, 9-connected topological network. Furthermore, the investigations of thermal stability and luminescent property of complex 1 indicate that compound 1 may be an excellent candidate for potential blue-light emitting material.A new coordination polymer, [Cd4(atz)6(PTA)] n has been firstly synthesized by employing mixed-ligand synthetic approach. Compound 1 presents a 3D microporous framework with an unprecedented 3, 9-connected topological network.Display Omitted
Keywords: 5-Amino-tetrazolate; In-situ; Mixed-ligand; Topology;

Stabilization of Pd, Pt and Ru nanoparticles by optically active CO/styrene copolymers by Isabelle Favier; David Picurelli; Christian Pradel; Jérôme Durand; Barbara Milani; Montserrat Gómez (766-768).
Fully isotactic, chiral CO/styrene copolymers were used as stabilizers for palladium, platinum and ruthenium nanoparticles synthesis. The tuning of copolymer/metal ratio and metal concentration were found to be key parameters in order to adjust the size and the agglomeration tendency of the metallic nanoclusters. These new materials were fully characterized by elemental analysis, infrared, solid state 13C MAS NMR spectroscopies, and transmission electronic microscopy. Platinum and ruthenium nanoparticles were tested as catalysts in the ethyl pyruvate hydrogenation, giving high activities; in this preliminary work, no enantioselectivity induction was observed.New nanomaterials have been obtained using isotactic, optically active, CO/styrene copolymers as stabilizers and tested in asymmetric hydrogenation of ethyl pyruvate.Display Omitted
Keywords: Metallic nanoparticles; Copolymers; Isotacticity; Stabilization; Catalysis; Hydrogenation;

The syntheses and structural characterization of methoxido- and ethoxido-vanadium complexes [VOCl2(OMe)(HOMe)2] (1), [VOCl(OMe)2]2 (2), and [{VOCl(OEt)2}2(THF)] (3) are described. The effects of the reactant ratio, starting materials, and reaction media on the formation of the alkoxido oxidovanadium and their molecular structures are reported. Complex 1 was prepared by reaction of VOCl3 with three equiv of MeOH in pentane. In the solid state, each molecule of 1 is linked with four symmetry related molecules through four O–H···Cl interactions resulting in the formation of a 2D infinite network. Reaction of VOCl3 with 2 equiv of NaOMe in pentane yields the dimeric complex 2, which features a pair of methoxido bridges in the molecular structure. In THF, reaction of VOCl3 with 2 equiv of NaOEt results in a very thermolabile [{VOCl(OEt)2}2(THF)] (3), which adopts a butterfly conformation in the molecular structure and features an interesting alkoxido oxidovandium with syn-orientated V=O functionality.Methoxido- and ethoxido-oxidovanadium(V) with different coordination geometry have been synthesized and characterized. Reaction of VOCl3 with 2 equivalents of NaOEt in tetrahydrofuran affords a novel solvent coordinated complex [VOCl(OEt)2]2(THF) (3) with the two V═O moieties syn-oriented in the solid state.Display Omitted
Keywords: Vanadium; O ligand; Chlorine; Hydrogen bonds; X-ray diffraction;

The first representatives of alkoxy-zircono-silsesquioxane compounds, dinuclear [Cy7Si7O12]Zr(ROH)(μ-OR)2Zr(ROH)[O12Si7Cy7], where R =  nPr, nBu, tBu; Cy = c-C6H11, and [Cy*7Si7O12]Zr(μ-ROH)(μ-OR)2Zr[O12Si7Cy*7], R =  tBu; Cy* = c-C5H9, have been prepared with quantitative yield by interaction of the corresponding zirconium alkoxides with the cycloalkyl-substituted cage silsesquioxanes in hexane. The X-ray single crystal study of the n-butoxide derivative revealed that zirconium atoms are hexacoordinated with the 3 oxygen atoms of the cage ligand, 2 — from the bridging alkoxide groups and one — from the solvating alcohol molecule in the coordination sphere. The molecule is additionally supported by a hydrogen bond between the solvating alcohol and an oxygen atom belonging to the cage ligand coordinated by the other zirconium atom. The structures of produced silsesquioxanes display behavior typical for metal–organic frameworks as they crystallize initially as hexane clathrates, but lose the solvent on storage in inert atmosphere. This results in formation of empty channels situated along the c-axis.Interaction of closo-silsesquioxanes with zirconium alkoxides in hexane offers an efficient approach to the first representatives of the family of alkoxy-zircono-silsesquioxanes. They crystallize as hexane clathrates, but lose the solvent on storage — a behavior typical of metal–organic frameworks.Display Omitted
Keywords: Metalla-silsesquioxanes; Zr-POSS; X-ray structure; Molecular model; Epoxidation catalyst; Hybrid material; MOF;

Trinuclear manganese(II) complexes of the compositions [Mn3(phen)6(ttc)](ClO4)3 (1), [Mn3(dmbpy)6(ttc)](ClO4)3∙ 2H2O (2) and [Mn3(bpy)6(ttc)](ClO4)3∙ 3H2O (3), where phen = 1,10-phenanthroline, dmbpy = 4,4′-dimethyl-2,2′-bipyridine, bpy = 2,2′-bipyridine and H3ttc = trithiocyanuric acid (2,4,6-trimercapto-1,3,5-triazine), were prepared and characterized by elemental analysis, FTIR and Raman spectroscopies, MALDI-TOF mass spectrometry, magnetic and conductivity measurements. The magnetic analysis incorporating simultaneous fitting of the temperature dependence and the field dependence of the magnetization using the isosceles triangle spin Hamiltonian model revealed a weak antiferromagnetic exchange within the trinuclear units.Trinuclear trithiocyanurato-bridged manganese(II) complexes were prepared and characterized by various techniques. Magnetic analysis revealed weak antiferromagnetic exchange within the trinuclear units.Display Omitted
Keywords: Trinuclear complexes; Manganese(II) complexes; Trithiocyanuric acid; Antiferromagnetic exchange;

A new binuclear mixed-valence complex [ReCl4(py)(μ-O)Re(py)4Cl]·2py was obtained by solvothermal synthesis in a Berghoff autoclave. It has been studied by IR, reflectance spectra, TGA and X-ray measurements, which support the assumption, that two Re centres with different coordination environments are present. Most plausible, yet not unambiguous oxidation state assignment is ReIII/IV.A new binuclear mixed-valence complex [ReCl4(py)(μ-O)Re(py)4Cl]·2py with Re centres of different coordination environments was obtained by solvothermal syntheses.Display Omitted
Keywords: Rhenium mixed-valence complex; Crystal structure; Solvothermal synthesis;

A radical ion-pair complex exhibiting strong C–H…O H-bonding interaction, moderately broaden near-IR absorbance and complicated EPR spectrum by Jian-Lan Liu; Qi Liu; Yun-Xia Sui; Bing-Qian Yao; Xiao-Ming Ren; Hui Zhang; Hai-Bao Duan; Qing-Jin Meng (786-788).
An ion-pair complex of [Ni(mnt)2]2− with p-N-benzylpyridinium α-nitronyl nitroxide radical cations (p-BzPYNN) in acetonitrile shows a moderate and broad absorbance in near-IR region. In the crystal of this complex, two radical cations form a dimer via strong H-bonding interaction; such kinds of dimers are connected into H-bonding chain by [Ni(mnt)2]2− dianions through weak H-bonding interactions. The neighboring H-bonding chains are arranged into supramolecular sheet via π…π stacking interactions between the five-membered chelate-ring of anion and the superimposed pyridyl rings of cations. The polycrystalline EPR spectrum exhibits two isotropic EPR signals. Based on the analyses of crystal structure, variable temperature magnetic susceptibility and electronic spectrum, the stronger EPR signal is assigned to the radical cation, the weaker one probably arises from a trace amount of [Ni(mnt)2]1− species.The polycrystalline EPR spectrum of an ion-pair complex of [Ni(mnt)2]2− with p-N-benzylpyridinium α-nitronyl nitroxide radicals (p-BzPYNN) exhibits two isotropic EPR signals, which origins were discussed.Display Omitted
Keywords: bis(maleonitriledithiolato)nickelate dianion; Imidazolidines-nitronyl nitroxide radical; Near-IR; EPR spectrum;

Synthesis, crystal structure and properties of two antimony germanate compounds by Bing Hu; Jian-Rong Li; Mei-Ling Feng; Xiao-Ying Huang (789-792).
Two antimony germanates formulated as [(enH2)2.5][SbGe8O18(OH)4] (1) (en = ethylenediamine) and Sb4Ge3O12 (2) have been solvothermally synthesized and structurally characterized. Compound 1 represents the first organic containing microporous antimony germanate with three-dimensional (3D) channels. Compound 2 is isostructural to the scintillation crystal BGO (Bi4Ge3O12) with 3D inorganic compact structure. The thermal stability of compound 1 and the optical properties of compound 2 have been studied.The first microporous antimony germanate [(enH2)2.5][SbGe8O18(OH)4] (1) was solvothermally synthesized; its structure features three-dimensional (3D) open framework of [SbGe8O18(OH)4]5− with double protonated ethylenediamine (enH2) cations templating in the 3D channels. The optical properties of compound Sb4Ge3O12 (2) were studied by diffuse reflectance and photoluminescence measurements.Display Omitted
Keywords: Antimony; Germanate; Microporous material; Crystal structures;

A hexanuclear cerium(IV) cluster with mixed coordination environment by Rajorshi Das; Rupam Sarma; Jubaraj B. Baruah (793-795).
Synthesis and structure of a modified intermediate derived from ammonium cerium(IV) nitrate for oxidative reactions as a hexanuclear cerium(IV) complex that has cerium ions in two different coordination environment is reported. The complex having ability to oxidise three moles of catechol to corresponding quinone has a composition NH4[Ce63-O)53-OH)32-C6H5COO)9(NO3)3(DMF)3].DMF.H2O is prepared under room temperature and is characterised by X-ray crystallography.A hexanuclear complex containing [Ce63-O)53-OH)3] core coordinated by benzoate and nitrate and dimethylformamide is isolated from simple reaction of sodium benzoate with ammonium cerium(IV) nitrate and characterised by determining its crystal structure. Per mole of this complex oxidises three moles of catechol to ortho-quinone at ambient condition.Display Omitted
Keywords: Hexanuclear cluster; Benzoate complex; Ammonium cerium(IV) nitrate; Mixed coordination environment; Oxidant;

The reaction of Cu(ClO4)2, N,N,N′,N″,N″-pentamethylethylenetriamine (pmedien) and sodium dicyanamide (Nadca) in aqueous medium led to the isolation of {[Cu(pmedien)(μ1,5-dca)]2(ClO4)2,[Cu(pmedien)(μ1,5-dca)]n(ClO4)n} (1). The complex was structurally and magnetically characterized. Single X-ray crystallography for 1 reveals the existence of two independent molecules in the unit cell: dinuclear doubly bridging complex and a 1-D polymeric chain with dca in both cases acting as a μ1,5-bridging ligand via the terminal nitrile nitrogen atoms. Magnetic susceptibility measurements of the complex showed that the Cu(II) ions are weakly coupled with ferromagnetic interaction in the dinuclear unit (J d  = 0.9 cm–1) and antiferromagnetic interaction in the polymeric chain (J c  = − 0.6 cm− 1).The complex {[Cu(pmedien)(μ1,5-dca)]2(ClO4)2,[Cu(pmedien)(μ1,5-dca)]n(ClO4)n} (1) was structurally and magnetically characterized. The unit cell contains two independent weakly coupled molecules: the ferromagnetic dinuclear doubly bridging complex and the aniferromagnetic 1-D polymeric chain with dca acting as a μ1,5-bridging ligand via the terminal nitrile nitrogen atoms.Display Omitted
Keywords: Crystal structure; Magnetic properties; Copper; Bridged dicyanamide; Polymeric dicyanamide;

A unique dinuclear palladium(II) complex of the general composition [Pd2(μ-L)4xDMF (DMF = N,N′-dimethylformamide, x  = 2 for 1a, x  = 4 for 1b) was prepared by a reaction of K2[Pd(mal)2] and two molar equivalents of 2-chloro-N6-benzyl-9-isopropyladenine (HL); mal stands for the malonate dianion. The prepared complex was fully characterized by elemental analysis, molar conductivity measurements, IR, Raman and NMR spectroscopies, ESI + mass spectrometry, TG/DTA thermal studies (for 1a), and by a single crystal X-ray analysis (for 1b). The results revealed that both metal centres are bridged by four N6-deprotonated 2-chloro-N6-benzyl-9-isopropyladenine molecules (L) in a paddle wheel-like arrangement with the Pd1⋯Pd1A separation of 2.7532(4) Å. Each of the L molecules is coordinated to the Pd(II) ions through its N6 and N7 atoms. The geometry around each of the central atoms can be described as distorted square-planar formed by two N6 and two N7 atoms. The [Pd2(μ-L)4xDMF complex represents the first dinuclear transition metal complex with two central ions bridged by four adenine derivatives coordinated through their N6 and N7 atoms.The [Pd2(μ-L)4]·xDMF complex (L=a deprotonated form of 2-chloro-N6-benzyl-9-isopropyladenine) represents the first dinuclear transition metal complex with two central Pd(II) atoms [Pd1···Pd1A separation of 2.7532(4)] connected by four adenine-based ligands in a paddle wheel-like arrangement coordinated through their N6 and N7 atoms.Display Omitted
Keywords: Palladium complex; Dinuclear; Adenine derivative; X-ray structure;