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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 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]

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]

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]

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]

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]

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: 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]