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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]

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]

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]

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]

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]

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]

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]