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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]

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]

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]

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]

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]

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]

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 high-nuclear wheel-shaped nanoscale clusters, [Co(H2O)6]{[C3H4N2]2[C5NH5]14[H15(Mo2O4)8Co16(PO4)14(HPO3)10(OH)3]}·5H2O (1) and [C3H5N2]4[C5NH5]2[Ni(H2O)6]{[C3H4N2]2[C5NH5]14[H18(Mo2O4)8Ni16(PO4)22(OH)6]}·11H2O (2), have been successfully synthesized employing the Py and Imi ligands as chemical modifiers. Both clusters take nanoscale wheel-like shapes, and the inorganic cores are wrapped up by the Py and Imi ligands acting as organic shells. In compounds 1 and 2, the polyoxoanion unit exhibits a new organic–inorganic hybrid polymolybdophosphate, representing the first two isolated POMs in the wheel-type {Mo/TM/P} materials, while Py and Imi ligands improve electric the delocalization effects of polyanions. It is worth noting that the molecular TPA cross section σ of compound 1 is 2.5 times that of compound 2, which demonstrates that the nonlinear optical property can also be improved by replacing part of the phosphate radicals with phosphite radicals through enhancing electron delocalization. [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]

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]

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]

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]

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 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]