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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]

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]

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]

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]

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]

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: 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]

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]

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]

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]

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]

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]

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]

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