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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]

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 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]

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]

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]