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A novel unexpected 1D coordination polymer Nd(Nphgly)(1,2-BDC)(H2O)·2H2O (1) containing simultaneously N-phthaloylglycine (Nphgly) and benzene-1,2-dicarboxylic acid (1,2-BDC) ligands has been prepared under the solvothermal conditions. In situ solvothermal aminolysis reaction occurred at benzene-1,2-dicarboxylic acid and glycine when they reacted with neodymium salts. Furthermore, the magnetic and luminescent properties of 1 were studied. [ABSTRACT FROM AUTHOR]

Five mono-nuclear silver (I) complexes with 6,7-dicyanodipyridoquinoxaline ligand, namely {[Ag(DPEphos)(dicnq)]NO3}2. CH3OH (1), [Ag(DPEphos)(dicnq)]BF4.CH3OH (2), [Ag(XANTphos) (dicnq)]CF3SO3 (3), {[Ag(XANTphos)(dicnq)]NO3}2 (4) and [Ag(XANTphos)(dicnq)]ClO4.CH2Cl2 (5) {DPEphos = bis[2-(diphenylphosphanyl) phenyl]ether, dicnq = 6,7-dicyanodipyridoquinoxaline, XANTphos = 9,9-dimethyl-4,5-bis(diphenylphosphanyl)xanthene} were characterized by X-ray diffraction, IR, 1H NMR, 31P NMR, fluorescence spectra and terahertz time-domain spectra (THz-TDS). In the five complexes the AgI, which is coordinated by two kinds of chelating ligands, adopts four-coordinate modes to generate mono-nuclear structures. The C-H...π interactions lead to formation of a 1D infinite chain for complexes 2 and 3. The crystal packing of complexes 1 and 5 reveal that they form 3D supermolecular network by several pairs of C-H...π interactions. The emissions of these complexes are attributed to ligands-centered [π-π8 ] transition based on both of the P-donor and N-donor ligands. [ABSTRACT FROM AUTHOR]

By using different N-donor organic species as additional auxiliary ligands with structure-directing roles, four three-dimensional (3D) calcium-based coordination complexes, [Ca(dbt)(H2O)]n1, [Ca(H-dbt)2(5,5′-dmbpy)2]n2, (4,4′-bpy)0.5[Ca(dbt)(H2O)2]n3, and (H2-dib)[Ca3(dbt)4(H2O)4·2H2O]n4 (H2-dbt = 2,5-dibromoterephthalic acid, 2,2′-bpy = 2,2′-bipyridine, 5,5′-dmbpy = 5,5′-dimethyl-2,2′-bipyridine, 4,4′-bpy = 4,4′-bipyridine, dib = 1,4-di(1H-imidazol-1-yl)benzene), have been successfully synthesized under similar solvothermal conditions and structurally characterized. The organic amine molecules play different roles in the formation of four different metal–organic skeletons with diverse structural topologies, in which complexes 1–3 are neutral, and 4 comprises a negatively charged framework with diprotonated dib as the counterion. Complex 1 features a 3D (6,6)-connected framework structure composed of edge-sharing 1D Ca–O–Ca inorganic chains and dbt ligands. The 2,2′-bpy molecule plays an important role in the synthesis of 1 as the structure-directing agent (SDA). Complex 2 shows a 3D 2-fold interpenetrated diamondoid framework (dia, 66) formed by single metal nodes via linear H-dbt anions and bidentate chelating 5,5′-dmbpy ligands, while complex 3 exhibits a 3D noninterpenetrated pcu network with {412·63} topology constructed from binuclear [Ca2(CO2)4] secondary building units and two types of dbt ligands, in which 4,4′-bpy molecules are ordered within the 3D neutral calcium-based framework as template and space filling agents. Complex 4 is a unique (4,4,4,4,5)-connected 5-nodal topology net, in which the diprotonated dib molecules provide space filling to balance the negatively charged framework. In addition, the thermal stability and the fluorescence properties of complexes 1–4 have been investigated. [ABSTRACT FROM AUTHOR]

From two series of Schiff base ligands, ( E)- N-(pyridine-2-yl)(CMe=NPhR) and ( E)- N-(pyridine-2-yl)(CH=NPhR) [R = H, L1a, L1b; 2-CH3, L2a, L2b; 4-CH3, L3a, L3b; 2,6-(CH3)2, L4a, L4b; 2,6-(C2H5)2, L5a, L5b; 2,6-( i-C3H7)2, L6a, L6b; 2,4,6-(CH3)3, L7a, L7b], fourteen mercury(II) complexes, namely, Hg 1a-Hg 7a and Hg 1b-Hg 7b were synthesized. Their structures were established by single-crystal X-ray diffraction, and they were physically characterized by 1H and 13C NMR spectroscopy, ESI-MS, FTIR spectroscopy, elemental analysis (EA), and powder XRD (PXRD). The crystal structures indicate that the position and type of substituent can directly influence the formation of 1D → 3D supramolecular metal-organic frameworks through C-H ···Cl and π-π interactions. Complexes Hg 1a-Hg 7a and Hg 1b-Hg 7b display deep blue emissions at λ = 401-428 nm in acetonitrile solution and light blue emissions at λ = 443-494 nm in the solid state. It is worth noting that Hg 1a, Hg 3a, Hg 1b, and Hg 3b exhibit good aggregation-induced emission (AIE) properties in CH3CN/H2O solutions. [ABSTRACT FROM AUTHOR]

Abstract: A fluorescent chemosensor, ortho-methylated boron-dipyrromethene (o-MBDP) has been synthesized and characterized. It featured excellent selectivity and sensitivity for Ag+ and Hg2+ ions, which could enhance the weak fluorescence of o-MBDP drastically by several hundred times through coordination and as a result, behave as an efficient “turn-on” fluorescent probe. The detection upper limit for Ag+ ion could be decreased by at least one order of magnitude with the introduction of the ortho-methyl group, in comparison with analogous boron-dipyrromethene (BDP) sensors, indicating the feasibility in extensive application areas as chemosensors. [Copyright &y& Elsevier]

A blue-green-emitting three-dimensional supramolecular compound (C10O2N2H8)(C9O7H6) (1) was synthesised under hydrothermal conditions and structurally characterised by elemental analysis, IR spectrum,1H NMR and single-crystal X-ray diffraction. The crystal belongs to triclinic system with P 1¯ space group. The crystal structure is stabilised by O–H…O, O–H…N hydrogen bonds and π–π interactions (π–π stacking distance is 3.282 Å). Compound1exhibits intense green luminescence in solid state at 298 K (λem = 546 nm). In addition, absorption and fluorescence characteristics of compound1have been investigated in different solvents (DMSO, CH3CN and CH3OH). The results show that compound1exhibits a large red shift in both absorption and emission spectra as solvent polarity increases (polarity: DMSO>CH3CN>CH3OH), indicating a change in dipole moment of compound1upon excitation. Although the emission spectra of compound1in CH3OH are close to it in dimethyl sulfoxide (DMSO), it is revealed that the luminescence behaviour of compound1depends not only on the polarity of environment but also on the hydrogen bonding properties of the solvent. Meanwhile, temperature strongly affects the emission spectra of compound1. Emission peaks of compound1were blue shift at 77 K than those at 298 K in both solid state (ca. 142 nm) and solution (ca. 6–23 nm), which was due to the non-radiative transition decreases at low temperature. Moreover, the quantum yield and fluorescence lifetime of compound1were also measured, which increased with increasing polarity of solvent, lifetime in DMSO at 298 K (τ1 = 0.92 μs, τ2 = 8.71 μs) was the longest one in solvents (298 K: τ1 = 0.87–0.92 μs, τ2 = 7.50–8.71 μs; 77 K: τ1 = 0.72–0.90 μs, τ2 = 6.88–7.45 μs), which was also shorter than that in solid state (298 K: τ1 = 1.13 μs, τ2 = 7.50 μs; 77 K: τ1 = 0.97 μs, τ2 = 8.97 μs). This was probably because of the weak polarity environment of compound1in solid state. [ABSTRACT FROM PUBLISHER]

Abstract: In this work, a T-shape organic molecule 5-(pyridin-4-yl)isophthalic acid was synthesized via a Suzuki coupling reaction and used as the ligand for a serial of mixed-lanthanide complexes. The chemical compositions of the lanthanide complexes were determined as (Eu x Tb1− x )2L3(H2O)4 by elemental analysis (EA) and thermo gravimetric analysis (TGA). The luminescent properties of the as-synthesized complexes were investigated and the intramolecular energy transfer mechanisms involved, were discussed. Efficient energy transfer from Tb3+ to Eu3+ was observed and controlled by changing the molar ratio of Tb3+ to Eu3+ ions, allowing the color tuning on the luminescent emission of the mixed-lanthanide complexes. [Copyright &y& Elsevier]