Inorganic Chemistry Communications (v.77, #C)

Contents List (iii-viii).

A series of isostructural lanthanide coordination polymers (Ln-CPs) {[Ln(Cbdcp)·3H2O]·Cl·xH2O} Ln = Tb (1), Eu (2), Dy (3), Cbdcp = N-(4-carboxybenzyl)-(3,5-dicarboxyl)pyridinium, have been successfully synthesized and fully characterized. Complex 1 utilized as a representative chemosensor has the potential to serve as the first example of a luminescent Ln-CP material based on the zwitterionic type of organic ligand for selective and recyclable sensing of TNP in ethanol solution. Besides, Complex 3 has antiferromagnetic property and exhibits slow magnetic relaxation.A series of isostructural lanthanide coordination polymers based on the zwitterionic type of organic ligand has been successfully synthesized to explore luminescent and magnetic properties. Complex 1 has the potential to serve as the first example of a luminescent zwitterionic Ln-CP material for selective and recyclable sensing of TNP in ethanol solution. Besides, Complex 3 has antiferromagnetic property and exhibits slow magnetic relaxation.Display Omitted
Keywords: Chemosensor; Magnetic property; Antiferromagnetic property; 2,4,6-Trinitrophenol; Sensor; Coordination polymer;

A new colorimetric chemosensor 1, containing the 7-nitrobenzo-2-oxo-1,3-diazolyl (NBD) moiety and the phenol one connected through Schiff-base linkage, has been synthesized. Sensor 1 showed remarkable color changes from pink to orange and pale brown, respectively, upon selective binding to Ni2 + and Cu2 + that can be identified by the naked-eye. The binding modes of sensor 1 to Ni2 + and Cu2 + were determined to be 1:1 stoichiometries using a Job plot and ESI-mass analysis. The sensor 1 showed high sensitivity toward Ni2 + and Cu2 + with the detection limits of 0.48 μM and 0.26 μM, respectively. The recognition properties of the sensor 1 toward Ni2 + and Cu2 + were explained by using photophysical experiments and theoretical calculations. Practically, sensor 1 functioned as a visible test strip for Ni2 + and Cu2 +.Display Omitted
Keywords: Nickel; Copper; Colorimetric; Test strip; Theoretical calculations;

Efficient and selective adsorption of nitroaromatic explosives by Zr-MOF by Zhuang Xu; Yuquan Wen; Li Tian; Guangtao Li (11-13).
Herein, the Zr-MOF UiO-66-NH2 was synthesized in a facile method. When the as-synthesized UiO-66-NH2 is served as an adsorbent for 2,4,6-trinitrophenol (PA), styphnic acid (TNR), 2,4-dinitrophenol (2,4-DNP), 2,4,6-trinitrotoluene (TNT), and 2,4-dinitrotoluene (2,4-DNT) in water, the absorption capacities are 0.0225, 0.024, 0.0296, 0.0005, and 0.002 g/g, respectively. This suggests that UiO-66-NH2 is an excellent adsorbent for PA, TNR, and 2,4-DNP and is promising material for the removal of PA, TNR, and 2,4-DNP from wastewater. The excellent adsorption performance is attributed to the hydrogen-bond interactions between UiO-66-NH2 and these explosives.Display Omitted
Keywords: Explosives; Selective absorption; UiO-66-NH2; Wastewater;

One rare 3D unipolar pillared-layer framework with a 1D carboxyl-copper chain formed by the syn-anti-COO group by Xue Zhang; Rui-Yu Zhu; Yi-Chen Liu; Qian Zou; Bang Chen; Jun-Jie Wang (14-17).
One 3D pillared-layer coordination polymer, [Cu(ipa)(bib)0.5(H2O)] (I), has been prepared from a solvothermal reaction of Cu(NO3)2·3H2O with isophthalic acid (H2 ipa) and 1,4-bis(imidazolyl)benzene (bib). The pyramid CuII node is connected by the ipa 2 − ion into a 2D simplified (4,4) layer with a 1D syn-anti-COO–CuII chain. The 2D layer is further unilaterally pillared by the bib spoke to afford a rare 3D unipolar pillared-layer framework. The overall topology can be described as a 6-connected self-catenated mab topology with point symbol of {44.610.8} through crosslink the (4,4) sheets. The magnetic properties have been studied, and the weak AFM interaction in the 1D chain has been estimated as − 0.15 cm− 1 by fitting the experimental data. Furthermore, the magneto-structural correlation has been well discussed.One 3D pillared-layer coordination polymer has been prepared from a solvothermal reaction of Cu(NO3)2·3H2O with isophthalic acid (H2 ipa) and 1,4-bis(imidazolyl)benzene (bib). The pyramid CuII node is connected by the ipa 2 − ion and the bib spoke to afford a rare 3D unipolar pillared-layer framework. The overall topology can be described as a 6-connected self-catenated mab topology with point symbol of {44.610.8} through crosslink the (4,4) sheets. The weak AFM interaction in the 1D chain has been estimated as − 0.15 cm− 1 by fitting the experimental data. Furthermore, the magneto-structural correlation has been well discussed.Display Omitted
Keywords: Isophthalic acid; 1,4-Bis(imidazolyl)benzene; Cu(II) coordination polymer; Crystal structure; Magnetic properties;

High-sensitive room-temperature NO2 sensor based on a soluble n-type phthalocyanine semiconductor by Zhen Dong; Xia Kong; Yanling Wu; Jinfu Zhang; Yanli Chen (18-22).
2(3),9(10),16(17),23(24)-tetrakis(2,2,2-trifluoroethoxy) phthalocyanine H2Pc(OCH2CF3)4(1) has been synthesized characterized by using MALDI-TOF MS, 1H NMR, UV–vis spectra and differential pulse voltammetry. Our work addresses this by introducing four electron-withdrawing trifluoroethoxy substituents at the periphery of the phthalocyanine ring to ensure the sufficient solubility and suitable LUMO energy level and thus successfully realize soluble n-type organic semiconductor. Furthermore, H2Pc(OCH2CF3)4 exhibited the high crystallinity and large specific surface area as well as good conductivity in the thin solid film fabricated by a simple solution-based quasi–Langmuir–Shäfer (QLS) method. Importantly, the highly sensitive, stable and reproducible responses to electron-accepting gas NO2 in 100–500 ppb range are observed for the QLS film of 1 at room temperature, implying the excellent potential of 1 as the NO2 sensor for applications in practical environments. In addition, the response of the QLS film of 1 is linearly correlated to the NO2 concentration. The interaction between the H2Pc(OCH2CF3)4 film and NO2 molecules with different concentrations was found to follow first-order kinetics. The present result represents not only the first example of n-type phthalocyanine-based NO2 sensor obtained by a solution-based method, but more importantly provides a new strategy for the molecular design to obtain soluble n-channel organic semiconductors in the field of sensing device fabrication.A new soluble n-type phthalocyanine semiconductor (1) is successfully synthesized by introducing four electron-withdrawing trifluoroethoxy substituents at the periphery of the phthalocyanine ring for optimizing molecular energy level. Highly sensitive, stable and reproducible responses to NO2 in 100–500 ppb range are observed for the solution-based QLS film of 1 at room temperature, depending on highly ordered film-structure, good crystallinity and conductivity of the QLS film of 1.Display Omitted
Keywords: Phthalocyanine; Gas sensor; Self-assemblies; N-type semiconductor;

Self-organization of unprecedented POMCPs with four-fold helixes based on the highest connected Keggin POMs by Xiya Yang; Guangjun Liu; Peipei Zhu; Jingquan Sha; Xiumei Zhang; Shuxian Li (23-26).
A new Keggin polyoxometalate based inorganic-organic hybrid compound, [Ag5(trz)4·(H2O)2][H2PW12O40] (1), was successfully synthesized and characterized. Single crystal X-ray analysis reveals that the title compound possesses fourfold meso-helical structure fabricated by POM-Ag inorganic chains, then the 1D metal-organic chains insert into the 3D POM-Ag framework using Ag as their common junction obtaining the whole structure with {4}8{48  · 896  · 1216} topolopy. The title compound represents the most complex helical conformation (fourfold meso-helix) among the Keggin based hybrids' materials to date, and [PW12O40]3 − polyanions in the title compound also exhibit the highest coordination number so far, which dominates the formation of fourfold meso-helix.The highest coordination mode of Keggin POMs dominates fourfold meso-helixes constructed by POM-Ag inorganic chains, which represents the most complex helical conformation among the Keggin based hybrids materials.Display Omitted
Keywords: Self-organization; Polyoxometalate; Helix; Triazole;

Field-induced slow relaxation of a manganese(III)-based single-ion magnet by Yi-Ming Liu; Zhong-Yi Liu; En-Cui Yang; Xiao-Jun Zhao (27-30).
A field-induced MnIII-based single-ion magnet with axially elongated Jahn–Teller distortion was well isolated in a layered complex by diamagnetic NaI ions, which exhibits an effective thermal-activated energy barrier of 12.9 cm− 1 under 2.0 kOe dc field resulting from strongly axial anisotropy of the high-spin MnIII ion.A field-induced MnIII-based single-ion magnet with axially elongated Jahn–Teller distortion was well isolated in a layered complex by diamagnetic NaI ions, exhibiting an effective energy barrier of 12.9 cm− 1 under 2.0 kOe dc field resulting from strongly axial anisotropy of the high-spin MnIII ion.Display Omitted
Keywords: Single-ion magnet; Ligand-field effect; Jahn–Teller distortion; Effective energy barrier; Zero-field splitting;

The syntheses and characterization of new nitro complexes of Ru(II) with 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tptz) and different substituted bipyridines are reported. A disproportionation reaction can occur after applying an oxidation potential corresponding to the couple RuII/RuIII forming the nitrate and the nitrosyl complexes, which were detected by cyclic voltammetry. This reaction was confirmed by IR-spectroelectrochemistry with an OTTLE cell, for the first time. Additionally, for 2,2′-bipyridine we have obtained as ClO4 salt a new nitrosyl-complex which presents an elevated IR stretching frequency.Display Omitted
Keywords: Nitro polypyridyl ruthenium (II) complexes; tris(2-Pyridyl)-1,3,5-triazine; Nitrosyl complexes; FT-IR spectroelectrochemistry;

Two novel Zn-based coordination polymer through employing of in-situ solvothermal techniques by using NO2-bdc (2-nitroterephthalic acid), HL1  = 1-(tetrazo-5-yl)-4-(triazo-1-yl)benzene, HL2  = 1-(tetrazo-5-yl)-4-(triazo-1-yl)benzene and Zn(NO3)2·6H2O to form [Zn 2 (HL 1 ) 2 (NO 2 -bdc)]·0.5 (DMA)·CH 3 OH·H 2 O (1) and [Zn 2 (μ 3 -OH) (HL 2 )·(NO 2 -bdc)]·0.5 (DMA)·H 2 O (2). The structures have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. In Compound 1, each Zn ion bridges one NO2-bdc and two HL1 ligands to yield infinite 2D layers, furthermore the aromatic π –π interactions link the adjacent layers yielding a 3D supramolecular structure. In compound 2, the HL2 ligands link Zn ions to form a 2D Zn(HL) sheet firstly, and further connected by double NO2-bdc pillars resulting in bi-pillared-layer type 3D frameworks. Moreover, 1 and 2 are luminescent with blue emission (λem  = 440 nm and λem  = 417 nm) in the solid-state. The fluorescent nature of 1and 2 inspired us to explore its potential application as a sensor for the detection of nitro explosives. The result reveals that 1 and 2 could be applied as a fluorescence sensor for NB (nitrobenzene) and 1,3-DNB (1,3-dinitrobenzene) with sensitivity and selectivity.Two novel Zn-based coordination polymer based on mixed ligands, [Zn2(HL1)2(NO2-bdc)(DMA)(MeOH)2]n (1) and [Zn2(μ 3-OH) (HL2)·(NO2)]·0.5 (DMA)·H2O (2) were successfully synthesized under solvothermal condition, characterized by single-crystal X-ray diffraction, IR spectroscopy, thermogravimetric analysis (TGA). The fluorescent nature of 1 and 2 inspired us to explore its potential application as a sensor for the detection of nitro explosives.Display Omitted
Keywords: Coordination polymer; 2D layer; Bi-pillared-layer; Luminescent sensor;

Two mononuclear DyIII complexes [Dy(H2TEG)(NO3)3]·[18-crown-6] (H2TEG = triethylene glycol) (1) and [Dy(H2TEG)Cl3]·[18-crown-6] (2) have been prepared using H2TEG as ligands. Magnetic studies revealed that both complexes show field-induced double magnetic relaxation behavior with energy barriers of 28 K and 54 K. Distinct magnetic dynamic properties observed in 1 and 2 are mostly attributed to the dissimilar coordination environments around DyIII centers in these two complexes.The preparation and magnetic studies of two mononuclear DyIII complexes based on triethylene glycol ligand are presented. Both complexes show field-induced single molecule magnet behavior with double magnetic relaxation processes. Distinct magnetic dynamic properties observed in these two complexes are mostly attributed to the dissimilar coordination environments around DyIII centers.Display Omitted
Keywords: Single molecule magnet; Two-step relaxation; Pentagonal bipyramid; Triethylene glycol;

Calcium borohydride allows for the high-yielding synthesis of (C5Me5)2An(η 3-H3BH)2 (An = Th, U) by reaction with (C5Me5)2AnCl2 (An = Th, U). While a preparative synthesis of (C5Me5)2U(η 3-H3BH)2 has been previously reported in the literature using K(C5Me5) and U(BH4)4, the use of Ca(BH4)2 is higher yielding and mild. Full characterization of the novel compound (C5Me5)2Th(η 3-H3BH)2 is presented.
Keywords: Borohydride; Thorium; Uranium; Pentamethylcylopentadienyl; X-ray crystallography;

Synthesis and characterisation of heterotrinuclear transition metal complexes for biomimetic proton reduction by Christoph Topf; Manuel Kaiser; Uwe Monkowius; Günther Knör (47-50).
Selected structural, spectroscopic, electrochemical and photochemical properties of novel heterotrinuclear [FeFe]-hydrogenase enzyme model compounds carrying a catalytic iron sulfur cluster site directly coupled to different transition metal subunits are reported. Typical metal-to-ligand charge transfer (MLCT) chromophores based on electron donating copper(I), rhenium(I) and tungsten(0) complex fragments were selected to provide both long-wavelength spectral sensitization and photoredox activity. Photoinduced one-electron transfer from the MLCT donor subunit to the diiron acceptor site could be observed with an efficient steady-state accumulation of the corresponding charge-separated state. The reduced iron site of these deeply coloured heterotrinuclear [FeFe]-hydrogenase model systems has been shown to be electrocatalytically active for proton reduction in the presence of trifluoroacetic acid (TFA). However, a successful visible-light powered system for catalytic hydrogen release in homogeneous solution could not be achieved, and the reaction remained stoichiometric with all of the systems investigated.Display Omitted
Keywords: Diiron complexes; Bridging ligands; Hydrogenase models; Biomimetic catalysis; Photochemistry;

Tuning of the fluorescence properties of [Ru (bpy) 2 (L1)] 2 + (1) [L1  = 2-(2-methoxyphenyl)-1H–imidazo [4, 5-f] Kumar et al. (2010), Rawle et al. (1992) phenanthroline] by DNA and/or Cu2 + ion have been investigated. Fluorescence of 1 gets enhanced upon binding to DNA owing to electrostatic interactions. The binding constant of 8.4 × 104 has been evaluated. Cu2 + ions though unable to alter the fluorescence intensity of free 1 but successfully sequestrate the DNA bound 1, evidently decreasing its fluorescence intensity. The reversibility of the sequestration process was ascertained by the recovery of the quenched fluorescence intensity via introduction of equimolar EDTA to the buffer system of DNA bound 1 and Cu2 +.Display Omitted
Keywords: 10-phenanthroline; UV–vis; Fluorescence; DNA; Electrostatic interactions; Cu (II)/EDTA modulation;

Co-shielding of neutron and γ-ray with bismuth borate nanoparticles fabricated via a facile sol-gel method by Dong Zhou; Quan-Ping Zhang; Jian Zheng; You Wu; Yang Zhao; Yuan-Lin Zhou (55-58).
Developing state-of-the-art materials for protecting human from unwanted ionizing radiations is urgent and significant for the rapid development of nuclear facilities. Here, bismuth borate nanoparticles have been fabricated via a facile sol-gel process. Characterization with X-ray diffraction, scanning electron microscopy, and transmission electron microscopy reveals that the product is composed of high-purity orthorhombic Bi6B10O24 phase and exhibits a typical single crystal with the size ranging from 100 to 300 nm. The product has an excellent ability to jointly attenuate both neutron and γ-ray. This significant work provides a material with not only good radiation shielding but also other fascinating features, such as environment-friendly.Display Omitted
Keywords: Radiation shielding; Nanoparticles; Bismuth borate; Sol-gel;

Two interesting dinuclear Zn(II)-compounds Zn2L3Cl4 (1) and Zn2L4Cl4 (2) were synthesized through the in situ zinc-induced reaction of simple pyridyl terminated (L1/L2)Schiff base ligands with ZnCl2 in the mixture solvents of DMF and pyridine at 80 °C for three days (where L1  = N-(2-pyridyl-methyl)-pyridine-2-carbaldimine, L2  = 1-(pyridin-2-yl)-N-(pyridin-2-yl-methylene)ethanamine, L3  = 2,3,5,6-tetra-(pyridin-2-yl)pyrazine, L4  = 1,2-di(pyridin-2-yl)-bis(1-(pyridin-2-yl)-ethylidene)ethane-1,2-diamine). The elemental analysis (EA) and IR results reveal that in situ formation of one new ligand L3 in 1 involves two C―C coupling reactions from two molecular L 1 featuring H atom in α-carbon of ―C=N― moiety, while in situ formation of another new ligand L4 in 2 involves one C―C coupling reaction from L 2 featuring –CH3 group in α-carbon of ―C=N― moiety. Obviously, different molecular structures between 1 and 2 closely related to the different substituents in simple Schiff base ligands. Moreover, the fluorescent properties of compounds 1 and 2 were also studied.Two 0-D dinuclear zinc(II) azaheterocyclic complexes 12 were substituent-dependent, in which 1 involved in situ formation of 2,3,5,6-tetra-(pyridin-2-yl)pyrazine (L 3 ) via two C―C coupling reactions from pyridin-2-yl-N-(pyridin-2-ylmethylene)methanamine (L 1 ), while 2 in situ construction of 1,2-di(pyridin-2-yl)bis(1-(pyridin-2-yl)ethylidene)ethane-1,2-diamine (L 4 ) via one C―C coupling reaction from 1-(pyridin-2-yl)-N-(pyridin-2-ylmethylene)ethanamine (L 2 ).Display Omitted
Keywords: Substituent-dependent structure; Solvothermal in situ zinc-induced reaction; ―CHR―C=N― moiety; Fluorescence;

With transition metal (TM) complex cations as structure-directing agents (SDAs), one type of new organic-inorganic hybrid iodoargentates, namely, [TM(2,2-bipy)3]Ag5I7 (TM = Zn, Ni, Co), have been solvothermally synthesized and structurally characterized. All the title compounds contain one-dimensional (1D) [Ag5I7]2 − chains composed by [Ag5I10] units based on [AgI4] tetrahedra, which are interconnected by [TM(2,2-bipy)3]2 + via hydrogen bonds to form 3D supramolecular networks. The UV–vis diffuse-reflectance measurements reveal that the compounds possess semiconductor behaviors with band gaps of 1.94–2.58 eV tuned by different TM complex cations. The title hybrid materials feature stable photocatalytic degradation activities over organic pollutants under visible light irradiation mainly originating from the electron absorption abilities of TM complex cations. Based on radical-trapping experiments and electronic band structural calculation, the possible photocatalytic mechanism and photochemical stability is also proposed.Display Omitted
Keywords: Inorganic-organic hybrid iodoargentate; Crystal structure; Visible light photocatalytst;

Cytotoxicity of a metal–organic framework: Drug delivery by Aiqing Ma; Zhidong Luo; Chuying Gu; Baohong Li; Jianqiang Liu (68-71).
A new Zn(II) metal–organic framework of [Zn6(L)3(DMA)4]·5DMA (1) (H4L = [1,1′:3′,1″-terphenyl]-3,3″,5,5″-tetracarboxylic acid), was used as a drug carrier of 5-fluorouracil (5-FU) for drug delivery. Drug release behavior was also investigated under different pH condition. 5-FU is released in a highly controlled and progressive manner with 95.8% of the drug release after 96 h at acidic condition and with 91.6% after 96 h at PBS. Vitro cytotoxicity assays indicated that the 1 possesses no obvious cytotoxicity.A new MOF was used as a drug vehicle of 5-fluorouracil (5-FU) for drug delivery. In vitro cytotoxicity assays indicated that the 1 possesses no obvious cytotoxicity.Display Omitted
Keywords: Drug delivery; Cytotoxicity assay; Metal–organic framework;

Synthesis, characterization and catalytic properties of a copper complex containing decavanadate nanocluster, Na2[Cu(H2O)6]2{V10O28}·4H2O by Mojtaba Amini; Mohammad Nikkhoo; Sajjad Bahadori Tekantappeh; S. Morteza F. Farnia; Ghodrat Mahmoudi; Orhan Büyükgüngör (72-76).
A copper complex containing decavanadate nanocluster, Na2[Cu(H2O)6]2{V10O28}·4H2O, was prepared by reaction of Cu(NO3)2·4H2O and NH4VO3 in an aqueous solution at pH = 4 and its structure was characterized using IR, CV and X-ray crystallography. It was found to be a highly efficient and effective catalyst for the azide alkyne cycloaddition and one-pot three-component (A3) coupling of aldehydes, amines, and alkynes to produce 1,2,3-triazoles and propargylamines respectively in high yields without any co-catalyst or activator.The azide alkyne cycloaddition and one-pot three-component (A3) coupling of aldehydes, amines, and alkynes to produce 1,2,3-triazoles and propargylamines respectively were conducted by a novel copper complex containing decavanadate cluster, Na2[Cu(H2O)6]2{V10O28}·4H2O.Display Omitted
Keywords: Nanocluster; Decavanadate; Copper; Azide-alkyne cycloaddition; A3-coupling;

A new topology of hexanuclear Mn/Ln clusters: Synthesis, structures and magnetic properties by Lei Sun; Hui Chen; Chengbing Ma; Changneng Chen (77-79).
Reactions of manganese nitrate and lanthanide nitrate hexahydrate with 2-(hydroxymethyl)pyridine (hmpH) and trimethylacetic acid as co-ligands in the mixture solutions of acetonitrile and ethanol generated two hexanuclear Mn-Ln compounds [Mn4La2O2(hmp)7(tBuCO2)2.5(NO3)4.5] [Ln = La (1), Nd (2)]. Compounds 1 and 2 are isostructural and possess a core of [MnIII 4LaIII 2(μ 4-O)(μ 3-O)(μ 3-OR)(μ 2-O)7]2 −, which comprises three face-sharing defected cubane units. The species are new additions to the Mn/Ln clusters and the broader class of 3d/4f molecular systems. The solid-state direct current magnetic susceptibility analyses indicate the antiferromagnetic interactions within two compounds. The systematic investigation summarized that the variation of auxiliary ligand carboxylate R group affects structural distortions and switch the magnetic behaviour.Display Omitted
Keywords: Mn/Ln clusters; New topology; Single molecule magnets;

When attempting to apply a Riley oxidation to a stannylated precursor instead of the expected aldehyde an acyclic triselenide was obtained in which a Se3 chain replaces the n Bu3Sn substituents of two precursors. The reaction was found to be fully reproducible. The product bearing the Se3 moiety and, hence, potentially possessing beneficial biological activity was analyzed comprehensively including X-ray structural characterization and 77Se NMR.Display Omitted
Keywords: Triselenides; Riley oxidation; Selenium dioxide; Stannylation; Catenation;