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A series of thioether-functionalised imidazolium salts have been prepared and characterized. Subsequent reaction of the thioether-functionalised imidazolium salts with iodomethane affords imidazolium-sulfonium salts composed of doubly charged cations and two different anions. Imidazolium-sulfonium salts containing a single anion type are obtained either by a solvent extraction method or by anion exchange. The imidazolium-sulfonium salts undergo a methyl-transfer reaction on exposure to water, giving rise to a new, singly charged imidazolium salt with iodide introduced at the 2-position of the imidazolium ring. Crystal structures of some of the imidazolium-sulfonium salts were determined by X-ray crystallography providing the topology of the interactions between the dications and the anions. Electrospray ionization mass spectrometry and quantum-chemical calculations were used to rationalise the relative strength of these interactions. [ABSTRACT FROM AUTHOR]

A series of three novel metal-organic frameworks, [CdL]n (1), [ZnL]n (2), and [Cu2L2(DMF)2]·6H2O (3), were successfully prepared by a solvothermal method using 3,3′-dimethoxy-4,4′-biphenyldicarboxylic acid (H2L) as the ligands. X-ray crystallography analysis reveals that complex 1 exhibits a 3D framework with sra topology and a rare eight-coordinated Cd(II) with two bound methoxy groups as secondary building unit (SBU). For complex 2, a 2D coordination network with a four-coordinated Zn(II) as SBU was observed. Complex 3 also shows a 2D layered architecture with 44 square lattice topology and a paddle-wheel Cu2(−CO2)4 as SBU. 113Cd NMR spectrum of 1 showed that the chemical shift of eight-coordinated Cd(II) appeared at δ −108.9 ppm. In addition, both 1 and 2 are robust coordination polymers with high thermal stabilities (>380 °C). Fluorescence measurements of 1 and 2 display medium strong emission peaks at 403 and 401 nm, respectively. Magnetic study of 3 exhibits a strong antiferromagnetic interaction between two Cu(II) ions with −2J = 286 cm−1. Three novel MOFs, [CdL]n (1), [ZnL]n (2) and [Cu2L2(DMF)2]·6H2O (3) (H2L = 3,3′-dimethoxy-4,4′-biphenyldicarboxylic acid) were obtained. 1 is a 3D framework with sra topology and an eight-coordinated Cd(II). 2 and 3 possess 2D coordination network. Both 1 and 2 show high thermal stabilities and medium fluorescent emission peaks. 3 exhibits a strong antiferromagnetic interaction. [ABSTRACT FROM AUTHOR]

Abstract: A novel two-dimensional (2D) copper(II) coordination polymer, [CuL(N3)2] n (1) (L=2-aminomethylpyridine), has been synthesized and characterized by elemental analysis, IR, X-ray crystallography and magnetic susceptibility. The complex crystallizes in space group P21/c with a =9.940(3), b =8.057(2), c =12.310(4)Å, β =104.119(4)°, V =956.1(5)Å3, Z =4, with final R =0.0543. The copper(II) ion in 1 is coordinated through two N atoms of the ligand L and four N atoms from the azido ligands in an elongated octahedron. The polymer consists of (6,3) layers in which alternate double end-on (EO) and single end-to-end (EE) bridging modes are found. The pyridine rings coming from adjacent layers are stacked by π–π interactions. Magnetic measurements reveal a weak antiferromagnetic exchange between copper(II) ions in 1. [Copyright &y& Elsevier]

Abstract The rational design and synthesis of an efficient bielectrocatalyst for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) by tuning the chemical composition, structure and the catalytic sites of the hybrid materials is always of a great challenge. In this work, an innovative strategy based on the highly active N,N′-carbonyldiimidazole (CDI) is described to one-pot synthesis of a novel precursor for bifunctional O 2- electrocatalyst. The coordination of Co2+ with the in situ generated ligands imidazole and carbonate results in ultrafine cobalt carbonate (CoCO 3)-involved cobalt-based zeolitic imidazole framework (CoCO 3 /Co-ZIF). Owing to the presence of ultrafine CoCO 3 , carbonization of CoCO 3 /Co-ZIF at 800 °C under N 2 atmosphere endows the pyrolysis product with a special skeleton of carbon nanotube (CNT)-tipped end CoO x , multivalent CoO x wrapped in graphitic carbon layers. Thus, the resulting CoO x /Co-N-C exhibits the enhanced and durable ORR/OER performance in alkaline media, due to the fast electron and mass transfers. For ORR, a large limiting current density of 4.59 mA cm−2 can be obtained by CoOx/Co-N-C, which is comparable to that of Pt/C. For OER, it only needs an over potential of 1.65 V to achieve a current density of 10 mA cm−2, merely 30 mV behind IrO 2 (1.62 V). [ABSTRACT FROM AUTHOR]

Two new binuclear complexes, [Ni2L(OAc)2(H2O)]ClO4·H2O·CH2Cl2 (1) and [Zn2L(OAc)2]ClO4·CHCl3·0.5C6H12 (2), have been synthesized by using 2-[N,N-di(2-pyridylmethyl)aminomethyl]-6-(2-imidazolylmethyl)aminomethyl-4-methylphenol (HL) as a ligand. Complexes 1 and 2 have been characterized by FT-IR, powder X-ray diffraction, elemental analysis and single-crystal X-ray diffraction. X-ray crystallographic analyses show that 1 crystallizes in the triclinic P-1 space group, while 2 in the monoclinic C2/c space group. Both Ni1 and Ni2 in 1 are six-coordinate octahedra with a [Ni1O3N3] and [Ni2O4N2] configuration. In 2, the six-coordinate Zn1 cation displays a distorted octahedral [Zn1O3N3] configuration, while the five-coordinate Zn2 cation has a trigonal bipyramidal [Zn2O2N3] geometry. The intermolecular interactions in 1 and 2 have been investigated by 3D Hirshfeld surface analyses and 2D fingerprint plots to show that the prominent interactions are H···H and O···H/H···O contacts in 1 and H···H and Cl···H/H···Cl contacts in 2. Notably, the fluorescence emission of 2 has larger intensity than that of the free HL. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ferrocenyl and phenyl groups in cuprous cluster C1 form aromatic microenvironment. • SMP C1 successfully activate inert Ph-Cl in visible-light-driven amination. • SET route for Ph-I/Br and EnT route for Ph-Cl proposed in SMP catalyzed amination. Amination of aryl halides is an important tool in organic synthesis and the activation of inert aryl chlorides is particular difficult. We herein report the first study of aromatic microenvironment modulation of cuprous clusters as single-molecule metallaphotocatalysts (SMPs) for direct phneyl chloride activation in C N coupling reactions. Selenoether L1 was designed to afford aromatic microenvironment with ferrocenyl and phenyl groups. The cuprous cluster [Cu 2 I 2 (L1)] (C1) was proved to be an effective white light-driven SMP , successfully catalyzing the amination of aryl halides with carbazole. This method showed a diverse substrate scopes of aryl halides with electronical and structural variety, affording the highest yield of 63% for 4-chlorobenzonitrile. X-ray crystallographic, in situ electron paramagnetic resonance (EPR) spectroscopic study and density functional theory (DFT) calculations demonstrated that the aromatic microenvironment in C1 promoted the effective intermolecular electron transfer via π-π interactions between SMPs and aryl halides. Interestingly, the mechanism of the amination was dependent on the substrates applied. A single electron transfer (SET) and formation of Cu2+ intermediate was found when Ph-I/Ph-Br were applied, while an energy transfer (EnT) route with Cu3+-intermediate was identified when Ph-Cl substrates were used. [ABSTRACT FROM AUTHOR]

Abstract: The structures and some molecular properties of the complexes M(mnt)2 2− (M=Ni, Pd, Pt and Zn, Cd, Hg; mnt2− =deprotonated maleonitriledithiolate) have been studied by using density functional theory (DFT) B3LYP/LanL2DZ level of theory. Computed binding energies show that the sequences of binding strengths are Ni

Metal–organic frameworks (MOFs) as proton-conductive materials have attracted increasing attention due to their applications in proton-exchange membrane fuel cells. While the majority of the MOFs are based on transition metals, group II metals with unusual configurations have received relatively less attention. In this work, we selected three tetrazole-based acetic acids, N,N-di(2-carboxymethyltetrazol-5-yl)amine (H2L1), 1,3,5-tri(2-carboxymethyltetrazol-5-yl)benzene (H3L2), and 4,5-di(tetrazol-5-yl)imidazolylacetic acid (H3L3), as ligands and prepared three MOFs with barium(II) ions: [Ba2(L1)2(H2O)5]·2H2O (1), (Me2NH2)[Ba(L2)(H2O)]·3H2O (2), and [Ba3(μ2-H2O)(L3)2(H2O)3]·2H2O (3). Ba-MOFs have been unambiguously characterized by elemental, FT-IR spectroscopy and single-crystal X-ray diffraction analyses. In the solid state, 2D MOF 1 with two nine-coordinated Ba(II) centers shows a rare hula hoop-like geometry at the Ba1 atom and a distorted tricapped trigonal prismatic geometry around the Ba2 one. Unusual sphenocorona geometry is also found in MOF 2 with a ten-coordinated Ba(II) ion. In MOF 3, three different Ba(II) ions coexist with two nine-coordinated Ba1 and Ba2 displaying a muffin-like configuration and a distorted tricapped trigonal prism geometry, respectively, and an eight-coordinated Ba3 having a distorted biaugmented trigonal prism geometry. In addition, MOF 2 exhibits an unprecedented trinodal 3,7,7-connected 3D network with the Schläfli symbol (37·46·52·62·74)(37·46·52·63·73)2(63) and MOF 3 displays a novel trinodal 4,5,9-connected 3D framework with the Schläfli symbol (421·615)(45·6)(48·62). Due to the presence of extensive hydrogen bonded networks consisting of dimethyl ammonium and water molecules in the 1D channels, MOF 2 shows a high proton conductivity of 4.47 × 10−3 S cm−1 at 85 °C and 98% relative humidity (RH). [ABSTRACT FROM AUTHOR]

• Photoactive and transition metal catalytic property of Cu n X n. • Redox ferrocene as electron shuttle to stabilize intermediates. • Mild reaction conditions and good functional group tolerance. This study investigated a series of ferrocenyltelluroether based cuprous halide clusters as effective single-molecule metallaphotocatalysts (SMP) in white light-driven C H arylation at room temperature and air. A systematic mechanistic study reveals that Cu(I) cluster can be irradiated by visible light to promote proton-coupled electron transfer (PCET), during which the electron from Cu(I)* leaves together with the proton from benzothiazole C H, leading to the formation of benzothiazolate-coordinated Cu(II) intermediate and aryl radical. Subsequently, the electron transfer (ET) from the ferrocene unit to the Cu(II) center releases the reactive benzothiazolate to form the target product with aryl radical. The advantages of these copper(I) halide clusters as SMP include high photocatalytic efficiency, structure adjustability, mild reaction conditions and good functional group tolerance. [ABSTRACT FROM AUTHOR]

3D lanthanide metal–organic frameworks (Ln–MOFs) with honeycomb cavities shown photocatalytic activities for the degradation of organic dyes. Using rational designed chalcone dicarboxylic acid ligand (H 2 L), a series of lanthanide metal–organic frameworks (Ln–MOFs) with the general formula Ln(HL) 3 (Ln = La ; Ce ; Pr ; Nd ; Sm ; Eu ; Gd) have been obtained under the solvothermal reaction. The crystal structure analysis displays that all the Ln – MOFs are the isomorphic three-dimensional (3D) metal–organic frameworks with honeycomb cavities, in which the porosity is ∼20% that calculated via PLATON software. In addition, photocatalytic activities of Ln–MOFs for the degradation of several organic dyes have been explored, suggesting that Ln–MOFs can be used as efficient heterogeneous photocatalyst for the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

The catalytic activities of eight copper(i) halide clusters assembled from copper(i) halide and ferrocenyltelluroethers, 1–8, were investigated in C–N formation under various conditions. A catalytic procedure using poly(ethylene glycol) (PEG-400) as a greener alternative organic solvent has been developed. The PEG-400/5 system can achieve 99% targeted yield with a mild reaction temperature and short reaction time. After the isolation of the products by extraction with diethyl ether, this PEG-400/cluster system could be easily recycled. Spectroscopic studies elucidate a stepwise mechanism: firstly, proton-coupled electron transfer (PCET) involving the transfer of an electron from Cu+ and a proton from imidazole results in the formation of a labile penta-coordinated Cu2+ and aryl radical; the following effective electron transfer from the ferrocene unit reduces Cu2+ and forms the target product; finally, the ferrocenium unit is reduced by the I− anion. The merits of this eco-friendly synthesis are the efficient utilization of reagents and easy recyclability. [ABSTRACT FROM AUTHOR]

Six new complexes [Mn( μ-O)(phpz)(MeOH)]·(MeOH)(HO) ( 1) [Co(HphpzH)(Hphpz)(phpz)]·4(MeOH) ( 2), Ni(Hphpz) ( 3), [Ni(Hphpz)]·HO ( 4), [Zn(pzpy)Cl] ( 5) and [Cu(pzpy)(HCO)(HO)] ( 6) have been synthesized by hydrothermal reactions of MCl·4HO (M = Mn, Co, Ni, Zn or Cu) with 5-(2-hydroxyphenyl)-3-pyrazole (HphpzH) or 2-(1 H-pyrazol-3-yl)pyridine (Hpzpy). The complexes were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Complex 1 is an octanuclear Mn(III) cluster, complexes 2 and 6 are binuclear Co(III) and Cu(II), respectively, complexes 3 and 4 are isomorphous mononuclear species, while complex 5 is a tetranuclear Zn(II) cluster. The magnetic behavior of complex 1 was investigated. Magnetic susceptibility measurements revealed antiferromagnetic exchange interactions between the metal centers in the clusters. The luminescence properties of the complexes were investigated at room temperature in the solid state. [ABSTRACT FROM AUTHOR]

Two new Mn(II) complexes,trans-[Mn(L1-L2)2(NCS)2] (1–2) with triaryltriazole (1, L1 = 3-(p-bromophenyl)-4-phenyl-5-(2-pyridyl)-1,2,4-triazole;2, L2 = 3,4-bis(p-methylphenyl)-5-(2-pyridyl)-1,2,4-triazole), have been synthesized and structurally characterized by elemental analysis, FT-IR, ESI-MS, and single-crystal X-ray crystallography. Crystallographic studies revealed that both1and2contain a distorted octahedral [MnN6] core with twotrans-disposed NCS−ions. The L1 ligand,1and2, together with four known homologous Mn(II) complexes,trans-[Mn(L3-L6)2(NCS)2] (3–6) (3, L3 = 3-(p-methoxyphenyl)-4-(p-chlorophenyl)-5-(2-pyridyl)-1,2,4-triazole;4, L4 = 3-(p-methoxyphenyl)-4-(p-bromophenyl)-5-(2-pyridyl)-1,2,4-triazole;5, L5 = 3-(p-chlorophenyl)-4-(p-methylphenyl)-5-(2-pyridyl)-1,2,4-triazole;6, L6 = 3,5-bis(2-pyridyl)-4-(p-methylphenyl)-1,2,4-triazole), were testedin vitrofor their antibacterial activities against two Gram-positive bacterial strains and two Gram-negative bacterial strains by the MTT method. The results indicate that1exhibited better activity than Penicillin and Kanamycin againstPseudomonas aeruginosaand also better than its free L1 ligand. [ABSTRACT FROM PUBLISHER]

Six new benzimidazolyl substituted triaryltriazoles, 3-(2-pyridyl)-4-( p-R-phenyl)-5-(2-benzimidazolyl)-1,2,4-triazoles ( L 1: R = OCH3; L 2: R = CH3; L 3: R = H; L 4: R = Br; L 5: R = Cl; L 6: R = F) were successfully synthesized. Yield of L 1-6 is in the range from 61 to 76%. The compounds L 1-6 were characterized by UV-vis, FTIR, 1H-NMR, ESI-MS spectra, and elemental analysis. Additionally, the absolute configurations of L 1-5 were determined by single crystal X-ray crystallography. [ABSTRACT FROM AUTHOR]

1D loop chain copper(I) cluster, [Cu 2 I 2 L 2 ] n , can be obtained based upon 9-(3-phenylselanyl-2-phenylselanylmethylpropyl)anthracene ( L ) and CuI. A facile in situ surface assembly strategy was designed to construct polymeric [Cu 2 I 2 L 2 ] n on the surface of TiO 2 nanoparticles. The visible-light photocatalytic property of core-shell TiO 2 -[Cu 2 I 2 L 2 ] n was confirmed by effective reduction of aqueous chromium(VI), showing a clear correlation to optical absorption ( E g = 2.8 eV). The key points of this strategy include high reactivity between copper(I) and soft selenium atom, efficient charge-transfer through polymeric cluster shell, and visible-light photoactivity of copper(I) halogen clusters. [ABSTRACT FROM AUTHOR]

Three different tetrazole-carboxylate ligands, monotetrazole-carboxylate H 2 tza (H 2 tza=1,5-tetrazole-diacetic acid), Hpztza (Hpztza=5-(2-pyrazinyl)tetrazole-2(1-methyl)acetic acid), ditetrazole-carboxylate H 2 tzpha (H 2 tzpha=1,3-di(tetrazole-5-yl)benzene-N2,N2′-diacetic acid) have been chosen to react with CdCl 2 ·6H 2 O, resulting in the formation of three new compounds [Cd 2 (tza) 2 ] ( 1 ), [Cd(pztza) 2 ] ( 2 ) and [Cd(tzpha)(CH 3 OH) 2 ] ( 3 ). The coordinate sites of the three ligands are major influenced by the different substituted group of tetrazole ring. These compounds have been characterized by elemental analysis, IR and single crystal X-ray diffraction. Compound 1 displays a complex 3D structure; compound 2 shows a 3D network and compound 3 features a 2D layer network. Furthermore, the luminescence properties investigated at room temperature in the solid state showed excellent ligand-centered luminescence. The obvious enhancement in luminescence makes these compounds potential materials for optical use. The differential scanning calorimetry (DSC) and thermogravimetric-differential thermogravimetric (TG-DTG) analyses were applied to evaluate the thermal decomposition behavior of such compounds, showing that compounds 2 and 3 can be used as potential energetic materials. The relevant thermodynamic parameters ΔH, ΔS and ΔG were calculated as well. [ABSTRACT FROM AUTHOR]

A derivative of 2-phenylpyridine (Hppy), 5-nitro-2-(3′,5′-di(trifluoromethyl)phenyl)pyridine (HL), is prepared. TheL-containing cyclometalated iridium(III) complexes with mono- and bidentate ancillary ligands, [Ir(L)2(PPh3)Cl] (1) and [Ir(L)2(pic)] (2, pic = picolinic acid), are synthesized and characterized. The photoluminescence (PL) spectra of1and2in CH2Cl2solutions show emission maxima at 558 and 560 nm, corresponding to yellow light emission with the Commission Internationale de L’éclairage (CIE) coordinates of (0.45, 0.54) and (0.46, 0.52), respectively. However, the luminescence intensity of2with PL quantum yield of 0.71 is obviously stronger that of1with PLQY of 0.19. The two-band white PL properties of2and [Ir(dfppy)2(PPh3)(NCS)] (3, dfppy = 2-(4,6-difluorophenyl)pyridine) with efficient blue light emission are investigated. The CH2Cl2solutions of2and3in the molar ratio of 1 : 5 show white light emission with the CIE coordinates of (0.33, 0.41). [ABSTRACT FROM PUBLISHER]

[Display omitted] • Two metal–organic frameworks, [Ag 2 L(bpy) 0.5 ] n (1) and [CoL(bpy)] n (2), were successfully obtained by coordinating chalcone dicarboxylic acid (H 2 L)/4,4′-bipyridine (bpy) with metal ions Ag+, Co2+. • Both compounds are multi-nuclear cluster structures and new topological structures have been observed. • As Ag ions in 1 is unsaturated coordination, its initial catatlytic property has been explored and meanwhile, 2 has a three-dimensional pore structure. Two metal–organic frameworks, [Ag 2 L(bpy) 0.5 ] n (1) and [CoL(bpy)] n (2), were successfully assembled through mixed-ligands strategy with different metal resource. Remarkably, both MOFs manifest multi-nuclear metal units as nodes and diverse topological structures. Compound 1 is an infinite two-dimensional layer structure with unsaturated four-nuclear silver unit nodes. While compound 2 exhibits a novel three-dimensional structure. The heterogeneous catalysis efficiency of the MOFs towards cycloaddition of N -methyl propargylamine with CO 2 has been explored, and compound 1 displays higher catalytic activity derived from bare Lewis acid silver active site. [ABSTRACT FROM AUTHOR]

Three pyrrolyl-substituted triaryltriazoles, 3-(N-methyl-2-pyrrolyl)-4-(p-R-phenyl)-5-(2-pyridyl)-1,2,4-triazole (L1: R = MeO; L2: R = Cl; L3: R = Br), and their mononuclear iron(II) complexes,trans-[Fe(L1–3)2(NCS)2]∙2MeOH (1: L1;2: L2;3: L3), have been synthesized and characterized by elemental analysis, FT-IR, ESI-MS, and single-crystal X-ray crystallography. Crystallographic studies revealed that1–3are isomorphous and crystallize in the triclinic space groupP-1. All the complexes have a similar octahedral [FeN6] core with twotrans-NCS−ions. Each ligand adopts a chelating bidentate coordination mode via the pyridyl N and one N of the triazole. Intermolecular O–H⋯O hydrogen bonding and C–H⋯πinteractions link the molecules of1–3to form a 1-D chain or 2-D framework. Variable-temperature magnetic susceptibility measurements indicated that all the complexes remained in a high-spin state from 1.8 to 300 K and had a weak antiferromagnetic interaction. [ABSTRACT FROM AUTHOR]

A of highly substituted 1 H-pyrazole-5-carboxylates 1 has been developed starting from easily available 4-aryl-2,4-diketoesters 2 and arylhydrazine hydrochlorides 3. More active 2-carbonyl group of 2 was blocked with methoxyamine hydrochloride to give 2-methoxy imine intermediates, which were then subjected to condensation with 3 in situ to provide the desired products 1. In addition, the geometrical configuration of 1aa was unambiguously confirmed by single crystal X-ray crystallography. [ABSTRACT FROM AUTHOR]

A series of cyclometalated Ir(III) complexes [Ir(dFNppy) 2 (PPh 3 )L] (PPh 3 = triphenylphosphine, L = Cl − , 1 ; NCS − , 2 ; NCO − , 3 ; N 3 − , 4 ) in which 5-nitro-2-(2′,4′-difluorophenyl)pyridyl ( dFNppy ) is used as the main ligand are synthesized and characterized. The crystal structures of 3 and 4 are determined by X-ray diffraction analyses. Photoluminescence spectra of 1 – 4 in CH 2 Cl 2 solutions at room temperature show the maximum emission wavelengths ( λ max ) in the range from 586 to 627 nm, corresponding to red-orange luminescence. HOMO–LUMO energy levels of 1 – 4 are estimated by cyclic voltammetry measurements. Compared with corresponding 2-phenylpyridyl ( ppy )-containing Ir(III) complexes having same ancillary ligands, 1 – 4 have obviously smaller HOMO–LUMO energy gaps ( E g ). Simultaneously, 1 – 4 show relatively bigger E g compared with 2-phenyl-5-nitropyridyl ( 5-NO 2 -ppy )-containing Ir(III) complexes possessing same ancillary ligands. Methods of E g adjustment are also discussed. [ABSTRACT FROM AUTHOR]

Three 3D lanthanide–organic frameworks (LOFs), [LnL(HCO2)(DMF)]n (Ln = Eu (1), Gd (2), Dy (3); H2L = 2,2′-dimethoxy-4,4′-biphenyldicarboxylic acid), have been prepared by the solvothermal reaction of Ln(NO3)3·6H2O and H2L in DMF–H2O mixed solvent. Crystallographic data show that LOFs 1–3 are isomorphous and crystallize in the orthorhombic space group Pna21. Each Ln(iii) is eight-coordinated to four O atoms from four L2− ligands, one O atom from the DMF molecule and three O atoms from HCO2−. The adjacent Ln(iii) ions are linked by the carboxylate groups of the L2− ligands and HCO2− to form a 1D inorganic rod-shaped [Ln(CO2)2(HCO2)]n chain as a secondary building unit (SBU). The infinite 1D chains are interconnected by the biphenyl groups, giving rise to a 3D framework along the c axis. LOFs 1–3 are the first neutral Ln-carboxylate/HCO2− chain-based sra-nets. 1 exhibits characteristic luminescence of Eu3+ upon 343 nm excitation. The investigation of magnetic properties shows very weak ferromagnetic interactions (J = 0.0092(3) cm−1) between Gd(iii) ions in 2 with a Gd–O–Gd bridging angle of 125.6(1)°, and ϑ = −1.9(2) K in 3 due to thermal depopulation of the Stark levels of Dy(iii) ions and/or the possible antiferromagnetic interactions between Dy(iii) ions in contrast to the single-ion behavior observed in 1. [ABSTRACT FROM AUTHOR]

Two heterocyclic compounds, 2-( p-bromophenyl)-5-(2-pyridyl)-1,3,4-oxadiazole ( 1) and 3-( p-bromophenyl)-4-phenyl-5-(2-pyridyl)-1,2,4-triazole ( 2) were successfully synthesized and characterized by UV-vis, FTIR, 1H NMR, ESI-MS spectra, elemental analysis, and single crystal X-ray crystallography. The structural analysis indicates that 1 is almost a planar molecule but 2 not. The crystal structure of 1 is stabilized by two kinds of π-π interactions and two types of C-H···N hydrogen bonds, whereas 2 by three kinds of C-H···π interactions and three types of C-H···N hydrogen bonds. Additional, 2 can be prepared directly from 1 in an aniline solution at 190°C in a yield of 70%. [ABSTRACT FROM AUTHOR]

Two new asymmetrical 3-( p-R-phenyl)-4-amino-5-(2-pyridyl)-1,2,4-triazoles ( 3a, R = CH3 and 3b, R = OCH3) were synthesized with a yield of 58% and 69%, respectively. The compounds 3a and 3b were characterized with FT-IR, 1H NMR, ESI-MS spectra, and elemental analysis. Additionally, their molecular and crystal structures were determined by single crystal X-ray analysis. [ABSTRACT FROM AUTHOR]

Abstract: Two mixed-donor molecules containing ferrocene and anthracene moiety, 1 and 2, have been designed and synthesized as potential multichannel probes for transition metal cations. They displayed switch-on fluorescence intensity only with Cu2+ among the metal ions examined. Electrochemistry and UV–vis spectra studies showed that Cu2+ induces the oxidation of ferrocene unit and then forms stable Cu+ complex. [Copyright &y& Elsevier]

Three polynuclear clusters, [Cu4L8](ClO4)4·4H2O (1), [Zn3L6(H2O)6](ClO4)6·6H2O (2), and [Mn3L6(CH3OH)6](ClO4)6·4.5H2O (3) (L = 4-(4-hydroxyphenyl)-1,2,4-triazole), obtained by the reactions of M(ClO4)2·6H2O with L have been isolated and structurally characterized. Complex1featured a tetranuclear Cu(I) structure. Both2and3are linear hexapositive trimers linked by three N1,N2–1,2,4-triazole ligands to the divalent central and terminal metal ions. Furthermore, the luminescence properties of2were investigated at room temperature in the solid state. Three new complexes with 4-(4-hydroxyphenyl)-1,2,4-triazole (L), [Cu4L8](ClO4)4·4H2O (1), [Zn3L6(H2O)6](ClO4)6·6H2O (2) and [Mn3L6(CH3OH)6](ClO4)6·4.5H2O (3), have been synthesized and characterized by single crystal X-ray crystallography. [ABSTRACT FROM AUTHOR]

Three iron(II) complexes with 3-(p-bromophenyl)-4-phenyl-5-(2-pyridyl)-1,2,4-triazole (L),trans-[FeL2(NCS)2] (1),trans-[FeL2(NCS)2]·2MeOH (1·2MeOH), andtrans-[FeL2(NCSe)2] (2), have been synthesized and characterized by elemental analysis, FT-IR, ESI-MS, and single crystal X-ray crystallography. Crystallographic studies reveal that all the complexes contain a distorted octahedral [FeN6] core with twotransNCS(Se)−ions. EachLadopts a chelating bidentate coordination via one N of pyridyl and one N of triazole. Magnetic susceptibility measurement indicated that both1and1·2MeOH are in a high-spin state from 2 to 300 K. Three iron(II) complexes with an asymmetrically 3,4,5-triarylsubstituted 1,2,4-triazole, [FeL2(NCS)2] (1), [FeL2(NCS)2]·2MeOH (1·2MeOH) and [FeL2(NCSe)2] (2), have been synthesized and characterized by single crystal X-ray crystallography. [ABSTRACT FROM PUBLISHER]

Abstract: Two one-dimensional (1D) germanium(IV) coordination polymers (CPs) containing macrocyclic tetraaza[14]annulene, [Ge(tmtaa)(L)] n [tmtaa=tetraaza[14]annulene, L=1,4-benezedicarboxylate 1; 2,5-dihydroxyl-1,4-benezedicarboxylate, 2], are synthesized and characterized. The temperature dependence of the electrical conductivity (σ) for 1 or 2 indicates region of rising dσ/dT (the conductivity increases with increasing temperature), suggesting semiconductor-like charge transport in the stacking direction. The room temperature electrical conductivities for 1 and 2 are 1.52×10−8 Scm−1 and 1.18×10−5 Scm−1, respectively, which are obviously higher than those of most 1D metallophthalocyanine- and metalloporphyrine-containing CPs. Though the crystal structures of 1 and 2 are similar, 2 exhibits better electrical conductivity which is about three orders higher than that of 1. This may be due to the protonic conduction existing in 2. Furthermore, 1 and 2 show outstanding thermal stability. These results suggest the potential applications of 1 and 2 as semiconductive materials. [Copyright &y& Elsevier]

Two novel quinolyl substituted triazoles, 3-( p-methoxyphenyl)-4-amino-5-(2-quinolyl)-1,2,4-triazole ( 5) and 3-( p-methoxyphenyl)-4-phenyl-5-(2-quinolyl)-1,2,4-triazole ( 6), were successfully synthesized. The compound 5 was synthesized under solvothermal conditions, whereas 6 was prepared through a solution method. Both 5 and 6 were characterized with UV-vis, FTIR, 1H-NMR, ESI-MS spectra, and elemental analysis. Additionally, the absolute configurations of 5 and 6 were determined by single-crystal X-ray crystallography. [ABSTRACT FROM AUTHOR]

Abstract: A novel iron(II) complex, trans-[FeL2(NCS)2][FeL2(CH3OH)2](NCS)2 (1) with 4-amino-3-(p-chlorophenyl)-5-(2-pyridyl)-1,2,4-triazole (L) has been successfully synthesized and characterized. X-ray crystallography analysis shows that 1 is the first example in the mononuclear triazole-based complexes consisting of two distinct molecules: trans-[FeL2(NCS)2] and trans-[FeL2(CH3OH)2](NCS)2 with each octahedral iron(II) center coordinated axial by two NCS− ions in Fe1 but two MeOH molecules in Fe2. Moreover, 1 can lose two MeOH molecules at 220°C to form trans-[FeL2(NCS)2] (2) which can be transformed to 1 when recrystallizing 2 in methanol. Both 1 and 2 are high-spin species in the range of 1.8–300K. [Copyright &y& Elsevier]

Triaryltriazoles are of interest in iron(II) complexes designed to study spin-crossover properties. In this study, three new asymmetrical substituted triaryltriazoles, 3-( p-R-phenyl)-4-( p-chlorophenyl)-5-(2-pyridyl)-1,2,4-triazoles (R = OCH3, 5a; Cl, 5b; Br, 5c), were successfully synthesized from 2-picolinic acid by a three-step reaction through an intermediate N-( p-R-phenylcarbonyl)- N′-(2-pyridylcarbonyl)hydrazine ( 4a-4c). Yield of 5a- 5c is in the range from 74 to 87%. The compounds 5a- 5c were characterized by UV, FTIR, 1H-NMR, electrospray ionization mass spectrum spectra, and elemental analysis. Additionally, the absolute configurations of 5a-5c were determined by single crystal X-ray crystallography. [ABSTRACT FROM AUTHOR]

Abstract: The template reaction of o-phenylenediamine, 1-benzoylacetone and nickelous acetate tetrahydrate results in two structure isomers, 6,17-dimethyl-8,15-diphenyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecinatonickel (II) (2) and 6,15-dimethyl-8,17-diphenyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecinatonickel (II) (4). However, the latter has been neglected in the previous research because of its low yield in the template reaction. The mechanism of this template reaction is discussed. Though the steric hindrance between the phenyl ring and the benzo ring in 2 is greater than that in 4, the intermediate of the former shows better structural stability than that of the latter, leading to obviously higher final yield of 2 compared with that of 4. n-Butyl alcohol is used artfully to separate the crude product of the template reaction into almost pure 2 and a mixture of 2 and 4 in a mole ratio of 1:5. The free base of 2, 5,14-dihydro-6,17-dimethyl-8,15-diphenyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecine (1), can be synthesized by demetalization of 2 with gaseous HCl. The same treatment to the mixture of 2 and 4 in a mole ratio of 1:5 leads to the free base of 4, 5,14-dihydro-6,15-dimethyl-8,17-diphenyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecine (3). The neglected macrocyclic compounds 3 and 4 have been characterized unambiguously and their single-crystal structures have also been determined by X-ray diffraction analysis for the first time. [Copyright &y& Elsevier]

Two linear trinuclear clusters, [Co3(L)6(H2O)6](ClO4)6 (1) and [Ni3(L)6(H2O)6](ClO4)6 · 3H2O (2) (L = 4-(4-hydroxyphenyl)-1,2,4-triazole), obtained by the reactions of M(ClO4)2 · 6H2O and 4-(4-hydroxyphenyl)-1,2,4-triazole have been isolated and structurally characterized. The two isostructural clusters, linear hexapositive trimers, are linked by three N1,N2-1,2,4-triazoles to the divalent central and terminal metal ions. The magnetic behaviors of the clusters were investigated from 1.8 to 300 K. Magnetic susceptibility measurements reveal antiferromagnetic exchange interactions between the metal centers in the clusters. The magnetic data were analyzed by using linear trinuclear modes with S = 3/2 and S = 1 for 1 and 2, respectively. Further studies were performed by accounting spin–orbital coupling for 1 and involving zero-field splitting within the ground state for 2. [ABSTRACT FROM AUTHOR]

Abstract: A new asymmetrical substituted triaryltriazole ligand, 3-(p-methoxyphenyl)-4-(p-bromophenyl)-5-(2-pyridyl)-1,2,4-triazole (L) and its complexes, trans-[MnL2(NCS)2] (1) and trans-[CuL2(ClO4)2] (2), have been successfully synthesized and characterized by UV, IR, ESI-MS, elemental analyses and single-crystal X-ray diffraction methods. In the structure, two L ligands are mainly stabilized by two kinds of intermolecular π⋯π interactions. In the complexes, each L ligand involves a chelating bidentate coordination mode via N atom of pyridyl group and one N atom of the triazole. Both complexes show a distorted octahedron containing two trans-coordinated anions in 1 with NCS− but in 2 with . The dihedral angle between the pyridyl and triazole ring in the free L ligand, 1 and 2 is 0.8(2)°, 12.8(2)° and 9.3(2)°, respectively, which represents the first example that the triazole–pyridyl twist angle in the complexes of any triaryltriazole is larger than that in the free L ligand. [Copyright &y& Elsevier]

Abstract: A series of new 2-phenyl-5-nitropyridyl containing iridium(III) cyclometalated complexes ([Ir(5-NO2-ppy)2Cl]2 (1, 5-NO2-ppy=2-phenyl-5-nitropyridyl), Ir(5-NO2-ppy)2(PPh3)Cl (2, PPh3 =triphenylphosphine), Ir(5-NO2-ppy)2(pic) (3, pic=picolinic acid)) have been synthesized and unambiguously characterized. The crystal structures of 2 and 3 have been determined by X-ray diffraction analyses. The HOMO–LUMO energy gaps of 1–3 estimated by the cyclic voltammetry (CV) show values in the order of 2 > 3 > 1. The UV–vis absorption and the solid photoluminescence (PL) spectra of 1–3 have also been measured, exhibiting the changing orders being consistent with that of the HOMO–LUMO energy gaps. Moreover, the UV–vis absorption spectra of 1–3 show obvious red-shifts compared with those of the corresponding 2-phenylpyridyl (ppy) containing Ir(III) complexes ([Ir(ppy)2Cl]2, Ir(ppy)2(PPh3)Cl and Ir(ppy)2(pic)) in which no strongly electron-withdrawing nitro groups are introduced to the pyridyl rings of the ppy ligands. Thus, the HOMO–LUMO energy gaps of 1–3 should be narrower than those of [Ir(ppy)2Cl]2, Ir(ppy)2(PPh3)Cl and Ir(ppy)2(pic). [Copyright &y& Elsevier]

Two new complexes, trans-[MnL2(NCS)2] (1) and trans-[CoL2(H2O)(EtOH)](ClO4)2 · H2O (2) with asymmetrical triaryltriazole ligands [L = 3-(p-chlorophenyl)-4-(p-methylphenyl)-5-(2-pyridyl)-1,2,4-triazole], have been synthesized and characterized by elemental analysis, FT-IR, ESI-MS, and single-crystal X-ray diffraction. In the complexes each L adopts a chelating bidentate mode via the nitrogen of pyridyl and triazole. Both complexes have a similar distorted octahedral core with two NCS- ions in the trans position in 1, while one H2O and one EtOH are present in the axial sites in 2. [ABSTRACT FROM AUTHOR]

Abstract: Two new heteroleptic iridium(III) complexes [Ir(4,6-dfppy)2(PPh3)L] (4,6-dfppy=2-(4,6-difluorophenyl)pyridyl, PPh3 =triphenylphosphine, L=NCS−, 1; NCO−, 2) have been synthesized and fully characterized. By introduction of electron-withdrawing groups such as fluorine atoms on the 4- and 6-positions of 2-phenylpyridyl (ppy) and using strong-field ligands for instance PPh3 and pseudohalogen as ancillary ligands, the HOMO–LUMO electronic energy gaps of 1 and 2 have been increased sufficiently. The photoluminescence (PL) spectra of 1 and 2 in solution show emission maxima at 456 and 458nm, respectively, corresponding to efficient blue light-emitting. X-ray analyses show that intra- and intermolecular π–π interactions exist in the solid state of 1 and 2. The PL spectra of 1 and 2 in solid state exhibit about 30nm spectral red shifts compared with those in solution. [Copyright &y& Elsevier]

Abstract: A series of new neutral iridium(III) complexes containing strong-field ancillary ligands, [Ir(ppy)2(PPh3)L] (ppy=2-phenylpyridine, PPh3 =triphenylphosphine, L=NCS−, 1; , 2; NCO−, 3), have been synthesized and fully characterized by 1H NMR, IR, ESI mass spectral and elemental analysis. The crystal structure of 1 has been determined by X-ray analysis. The photoluminescence (PL) spectra of 1–3 show emission maxima at 477, 489 and 485nm, respectively, corresponding to blue light-emitting of 1 and blue-green light-emitting of 2 and 3. PL quantum yields (PLQYs) of 1–3 are 0.39, 0.13 and 0.43, respectively. [Copyright &y& Elsevier]

A dinuclear nickel(II) complex, [Ni2(MOBPT)2(N3)4] · 2H2O (MOBPT = 4-(p-methoxyphenyl)-3,5-bis(pyridine-2-yl)-1,2,4-triazole), has been synthesized and characterized by elemental analysis, UV, IR, ESI-MS, and single crystal X-ray crystallography. The complex crystallizes in triclinic system, space group P1 with a = 9.877(2) Å, b = 10.396(2) Å, c = 11.975(3) Å, α = 71.638(3)°, β = 74.968(3)°, γ = 64.747(3)°, V = 1044.2(4) Å3, Z = 1, R = 0.0371 for 5774 observed reflections. The crystal structure determination shows that the dinuclear Ni2N8 unit is almost planar with each Ni2+ coordinated by four nitrogens from two MOBPT ligands and two axial azides in a distorted octahedral geometry. Magnetic measurements reveal weak antiferromagnetic exchange in the complex. [ABSTRACT FROM AUTHOR]

Abstract: In the title complexes, {[(η-C5H5)Fe(η-C5H4)(CO)](C22H21N4)Ni} (1) and {[(η-C5H5)Fe(η-C5H4)(CO)]2(C22H20N4)Ni} (2), one and two electroactive ferrocenes (Fc) were grafted onto the methine of the nickel complex Nitmtaa (H2tmtaa=4,11-dihydro-5,7,12,14-tetramethyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecine) through the carbonyl groups. The two new complexes were characterized by IR, UV, MS and NMR spectra as well as by DSC measurements. The crystal structure of 1 was determined. Ni coordinates to four nitrogen atoms of tmtaa, and it is almost in the same plane as the N4 plane. The mean Ni–N bond distance in the N4 plane is 1.866Å. The non-planar, saddle-shaped conformation of H2tmtaa is almost retained in the nickel complex. The symmetry axis of ferrocene is almost parallel to the N4 plane in Nitmtaa. The dihedral angle between the N4 plane in Nitmtaa and the cyclopentadienyl ring in ferrocene is 98.5°. The electrochemistry of 1 and 2 was studied by cyclic voltammetry in CH2Cl2/1×10−1 M n-Bu4NClO4 using a glass carbon working electrode. Because of the electron transfer between the electroactive ferrocene and the completely conjugated system of Nitmtaa, the complexes show novel electrochemical properties and the ferrocenes in 1 and 2 act as electron acceptors. [Copyright &y& Elsevier]

A novel 2-D coordination polymer constructed from high nuclearity nanosized Ho48 clusters was synthesised and structurally characterized using single-crystal X-ray analysis. The Ho48 cluster core with a charming waist drum-like structure was templated by CO32− ions, and bridged by Ho–N bonds to get a 2-D coordination polymer. [ABSTRACT FROM AUTHOR]

Abstract: 1-(Ferrocenylseleno)-3-(8-hydroxyquinoline)-propane was synthesized and studied as a fluorescent sensor for Zn2+ ion. It demonstrates good selectivity for sensing Zn2+ via ICT mechanism. [Copyright &y& Elsevier]

An abstract of the article "One-Pot Synthesis of Highly Substituted 1H-Pyrazole-5-carboxylates from 4-Aryl-2,4-diketoesters and Arylhydrazines" by Jiao-Jiao Zhai and colleagues is presented.

The dimeric [Cu(bipy)(μ2-OH)]4 [(H2O) (bipy)2HPW11Cu2O39] 2·2EtOH·10H2O Keggin polyoxometalate is prepared by solvothermal reaction of Cu(NO3)2, H3PW12O40, and bipy in H2O/EtOH (2:1) solution (pH 4.6 adjusted with H3PO3, autoclave, 150 °C, 3 d; 38% yield). [ABSTRACT FROM AUTHOR]

Triazole (VI) is obtained under solvothermal conditions, whereas triazole (VII) is prepared by a solution method. [ABSTRACT FROM AUTHOR]

Asymmetrical substituted triaryltriazoles (VI) are obtained in three steps starting from readily available 2-picolinic acid (I). [ABSTRACT FROM AUTHOR]

The new compound NH4{ [Zn4(DACH)7(H2O)3] [VIII3VIV18P6 O60(DACH)3]}·19H2O (DACH: 1,2-diaminocyclohexane) is synthesized by hydrothermal reaction of NH4VO3, Zn(OAc)2, DACH, H3PO4, and H2O (autoclave, 160 °C, 6 d). [ABSTRACT FROM AUTHOR]