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Abstract: Four new complexes, [Zn(cca)(phen)] n (1), [Co(cca)0.5(Hcca)(phen)(H2O)] (2), [Cu(cca)(phen)] n · nH2O (3), and [Mn(cca)(phen)(H2O)] n ·0.25nH2O (4) (H2cca= p-carboxycinnamic acid, phen=1,10-phenanthroline) were synthesized by hydrothermal reactions and characterized by single crystal X-ray diffraction. Complex 1 is of 3D structure constructed by coordination bonds, while complexes 2–4 consist of 3D supramolecular networks, which are assembled by coordination bonds, hydrogen bonds and π–π stacking interactions. In these complexes, p-carboxycinnamate anions (Hcca− and cca2−) adopt tetradentate, bidentate and monodentate modes to coordinate to metal ions, resulting in variety of supramolecular structures. [Copyright &y& Elsevier]

Abstract: Two new coordination polymers, [Cu2(oba)2(bpy)2.5] n ·2nH2O (1) and [Cu(bpndc)(bpy)0.5] n (2) (H2oba=4,4′-oxybis(benzoic acid); H2bpndc=benzophenone-4,4′-dicarboxylic acid; bpy=4,4′-bipyridine) were synthesized by the hydrothermal reactions and characterized by single crystal X-ray diffraction, elemental analysis and IR spectrum. In 1, oba2− anions adopt tridentate and bidentate mode, linking Cu(II) ions into 1D helical chains, and bpy ligands link Cu(II) ions into 1D chains too. These two kinds of chains are interconnected in the Cu(II) nodes, forming a complicated 3D network. In 2, bpndc2− anions adopt tetradentate mode, linking Cu(II) ions into 2D layers. These layers are connected by bpy ligands into a 3D network with small 1D channels. [Copyright &y& Elsevier]

Abstract: Three new lanthanide complexes, [La(HpicO)3(phen)(H2O)] n (1) and Ln3(picO)4(phen)3(H2O)2·HpicO·0.5H2O (Ln=Er (2), Yb (3)) were synthesized by the hydrothermal reactions and characterized by single crystal X-ray diffraction, elemental analysis and IR spectrum. In complex 1, each La(III) ion is 10-coordinated and HpicO− ligands link the metal ions into 1D zigzag chains. Complexes 2 and 3 are isomorphous, and there are three crystallographically independent Ln(III) ions in the asymmetric unit. The N–H⋯O and O–H⋯O hydrogen bonds and π–π stacking interactions in these complexes result in the formation of 3D supramolecular architectures. [Copyright &y& Elsevier]

The first examples of lanthanide(III) isoorotates were synthesized by hydrothermal reactions and characterized by single crystal X-ray diffraction. Isoorotate ions (H2iso- and Hiso2-) act as bidentate ligands and coordinate to the Ln(III) ions through the carboxylate oxygen and the adjacent carbonyl oxygen, forming a stable six-membered ring. But in the Pr(III) complex, Hiso2- acts as a tetradentate ligand, and in addition to the formation of the six-membered ring, another carbonyl oxygen atom and a deprotonated amido nitrogen atom are involved in coordination. There are O–H⋯O, N–H⋯O and/or N–H⋯N hydrogen bonds, and/or π–π stacking interactions in these complexes, resulting in the formation of 3D supramolecular networks. [Copyright &y& Elsevier]

Single crystal X-ray diffraction shows that [La(gly)2(H2O)2(phen)2(CH3CH2OH)](ClO4)3(phen)3·3H2O (1), [Ln(gly)2(H2O)2(phen)2](ClO4)3 (phen)4·nH2O [n=0, Ln=Nd (2); n=1, Ln=Ho (3)], and [Yb(gly)4(H2O)(phen)](ClO4)4(phen)2(gly+H)·2H2O (4) (gly=glycine, phen=1,10-phenanthroline) with the coordination number 9 for La3+, 8 for Nd3+ and Ho3+, and 7 for Yb3+, exhibit the effect of lanthanide contraction. Complexes 1–4 are all mononuclear structures, with the ligand glycine coordinated to the Ln3+ ion in the monodentate mode and in zwitterionic form. There exist free phen molecules and solvent molecules in the lattice. Therefore, there are different types of hydrogen bonding and π–π stacking interactions in the crystals that give rise to different supramolecular architectures. The structure of 1 is composed of 1D chains which extend in the [1 0 0] direction, while those of 2 and 3 are 2D structures extending in the (0 0 1) plane. However, complex 4 shows a complicated 3D network. [Copyright &y& Elsevier]

Three supramolecular lanthanum coordination compounds of amino acids, with 1,10-phenanthroline (phen), [La2(APA)6(phen)2(H2O)2](ClO4)6(phen)4·2H2O (1), [La2(ABA)6(phen)2(H2O)2](ClO4)6 (phen)6·4H2O (2), and [La2(AHA)4(phen)4](ClO4)6(phen)4·2H2O (3) (APA=3-aminopropionic acid; ABA=4-aminobutanoic acid; AHA=6-aminohexanoic acid) were synthesized and characterized by single crystal X-ray diffraction. The results show that the three coordination compounds are all composed of binuclear coordination cations built by metal-ligand coordination. Through hydrogen bonding and π–π stacking interactions, complex 1 forms a two-dimensional supramolecular sheet structure extending in the (001) plane, complex 2 forms a three-dimensional supramolecular network with many cavities occupied by ClO4− and lattice H2O molecules, and complex 3 forms a two-dimensional supramolecular lamellar structure in the (100) plane. [Copyright &y& Elsevier]

Two novel lanthanide supramolecular coordination polymers, {[Nd2(phth)3(phen)(H2O)]·H2O}n (1, phth=phthalate, phen=1,10-phenanthroline) and {[Ho2(phth)3(phen)(H2O)2]·3H2O}n (2), have been synthesized by hydrothermal method and characterized by X-ray diffraction. The results show that complex 1 crystallizes in triclinic space group P1¯ with a=7.605(2) A˚, b=12.972(4) A˚, c=18.773(6) A˚, α=109.778(5)°, β=91.657(5)°, γ=103.951(5)° and Z=2. Complex 1 has a one-dimentional nano-chain structure and the existence of hydrogen bonds and π–π interactions results in 2D network structure. Complex 2 crystallizes in triclinic space group P1¯ with a=11.695(2) A˚, b=13.488(3) A˚, c=13.761(3) A˚, α=87.09(3)°, β=67.40(3)°, γ=67.41(3)° and Z=2. Complex 2 features a zigzag double-chain and the hydrogen bonds lead to the formation of a three-dimensional network. Both Complex 1 and 2 have two metal environments. [Copyright &y& Elsevier]

Two binuclear europium complexes [Eu2(SA)6(phen)2]·6H2O (1) and [Eu2(SA)4(phen)2(H2O)4](ClO4)3 (phenH)·H2O (2) (where SA=succinamate, phen=1,10-phenanthroline) have been synthesized and characterized by X-ray single crystal diffraction. For 1, the unit cell contains two crystallographically independent Eu(SA)3(phen) species in which the Eu3+ ions have two different coordination environments. Two types of binuclear molecule are arranged in different orientations in the crystal. The 7F0→5D0 excitation peaks at 580.16 and 580.46 nm at 77 K and the Stark components of 5D0→7FJ transitions, especially 5D0→7F1 and 5D0→7F2 emission lines, show that complex 1 has two Eu(III) ion sites, which is in good agreement with the results of the structure determination. In complex 2, four water molecules take the place of two bidentate chelating SA anions in the inner coordination sphere of 1. Outside the coordination sphere, the protonated phen molecule forms a hydrogen bond with a tridentate-coordinated carboxyl group and has a π–π stacking interaction with the coordinated phen molecule. [Copyright &y& Elsevier]

A microscale metal-organic framework [Eu(atpt) 1.5 (phen)(H 2 O)] n (H 2 atpt = 2-aminoterephthalic acid, phen = 1,10-phenanthroline) (Eu-MOF) was synthesized and characterized by elemental analysis, luminescence spectrum, powder X-ray diffraction, dynamic light scattering and scanning electron microscope. The fluorescence response of Eu-MOF to metal ions and aldehydes showed that Eu-MOF is highly selective to Fe(III), Al(III) and 2-hydroxy-1-naphthaldehyde (2-OH-NA). Eu-MOF could be utilized as a multi-functional fluorescence chemosensor for Fe(III), Al(III) and 2-hydroxy-1-naphthaldehyde (2-OH-NA). The detection limit of Fe(III), Al(III) and 2-OH-NA was 45, 10 and 36 μM, respectively. The corresponding sensing mechanisms were explored. [ABSTRACT FROM AUTHOR]

Abstract: Three new coordination polymers, [Zn2(CCA)2(bpy)]n·0.5nbpy (1), [Zn(CCA)(bpe)(H2O)]n·0.5nH2O (2) and [Mn(CCA)(bpe)]n·2nH2O (3) (H2CCA = 2-carboxycinnamic acid; bpy = 4,4′-bipyridine; bpe = 1,2-bis(4-pyridyl)ethane) have been synthesized by the hydrothermal reactions and characterized by single crystal X-ray diffraction, elemental analysis and IR spectrum. Although both complexes 1 and 2 possess 3D metal-organic frameworks, CCA ligands adopt different coordination modes in them. This can be attributed to the introduction of different auxiliary ligands bpy and bpe. In complex 3, CCA ligands link Mn(II) ions into 1D infinite double-strand helical chains and these chains are bridged by bpe to 2D layers. There are hydrogen bonds among the free water molecules, leading to the formation of 1D infinite water chains, which play an important role in the construction of the 3D microporous network. The fluorescent properties of complexes 1 and 2 have also been investigated. [Copyright &y& Elsevier]

Abstract: Five new Cu(II) complexes [Cu(psa)(phen)]·3H2O (1), [Cu(psa)(2bpy)]·0.5H2O (2), [Cu(psa)(2bpy)(H2O)]·3H2O (3), [Cu(psa)(4bpy)]·H2O (4), and [Cu(psa)0.5(N3)(2bpy)] (5) (H2psa=phenylsuccinic acid, phen=1,10-phenanthroline, 2bpy=2,2′-bipyridine, and 4bpy=4,4′-bipyridine) were obtained under solvothermal conditions and characterized by single-crystal X-ray diffraction. Complexes 2 and 3 were formed by one-pot reaction. In complex 2, Cu(II) ion is four-coordinated and locates at a slightly distorted square center. In complex 3, the coordinated water molecule occupies the axial site of Cu(II) ion forming a tetragonal pyramid geometry. Complexes 1 and 3 are of 1D chain structures, and extended into 2D supramolecular network by hydrogen bonds. Complex 2 is of zipper structure, and further assembled into 2D supramolecular network by hydrogen bonds and π–π stacking interactions. Complex 4 is a 3D CdSO4-like structure with twofold interpenetration, while complex 5 is a dinuclear compound. The different structures of complexes 1–5 can be attributed to using the auxiliary ligands, indicating an important role of the auxiliary ligands in assembly and structure of the title complexes. [Copyright &y& Elsevier]

Abstract: The reaction of Zn(OAc)2·2H2O and pyrazine-2,6-dicarboxylic acid (H2pzda) with 2,2′-bipyridine (2,2′-bpy), 1,10-phenanthroline (phen) or 1,2-bis(4-pyridyl)-ethane (bpe) gave rise to three new Zn(II) complexes: [Zn(pzda)(2,2′-bpy)(H2O)]·0.5H2O (1), {[Zn(pzda)(phen)(H2O)]·H2O}2 (2) and [Zn2(pzda)2(bpe)(H2O)4]·1.75H2O (3), respectively. For 1, it is a mononuclear structure which is assembled into 3D supramolecular architecture by strong hydrogen bonds (O–H⋯O, O–H⋯N) as well as π–π stacking interactions. In 2, there are two similar mononuclear units, which are further constructed by the hydrogen bonds and π–π stacking interactions into zipper-like supramolecular structure. However, for 3, the bpe ligand bridges two Zn(II) ions cooperated with blocking ligand pzda into binuclear unit, and then the binuclear molecules are alternatively assembled into 3D supramolecular network by hydrogen bonds between the coordinated water molecules and the carboxylate oxygen atoms. The thermal properties of complexes were also investigated. [Copyright &y& Elsevier]

Abstract: Five new copper(II) complexes [Cu(dbsf)(H2O)] n ·0.5n(i-C3H7OH) (1), [Cu(dbsf)(4,4′-bpy)0.5] n · nH2O (2), [Cu(dbsf)(2,2′-bpy)(H2O)]2 ·(n-C3H7OH)·0.5H2O (3), [Cu(dbsf)(phen)(H2O)]2 ·1.5H2O (4) and [Cu(dbsf)(2,2′-bpy)(H2O)] n · n(i-C3H7OH) (5) (H2dbsf=4,4′-dicarboxybiphenyl sulfone, 4,4′-bpy=4,4′-bipyridine, 2,2′-bpy=2,2′-bipyridine, phen=1,10-phenanthroline, i-C3H7OH=isopropanol, n-C3H7OH= n-propanol) have been synthesized under hydro/solvothermal conditions. All of the complexes are assembled from V-shaped building blocks, [Cu(dbsf)]. Complex 1 is composed of 1D double-chains. In complex 2, dbsf2− ligands and 4,4′-bpy ligands connect Cu(II) ions into catenane-like 2D layers. These catenane-like 2D layers stack in an ABAB fashion to form a 3D supramolecular network. Complexes 3 and 4 are 0D dimers, in which two [Cu(dbsf)] units encircle to form dimetal macrocyclic molecules. However, in complex 5, the V-shaped building blocks [Cu(dbsf)] are joined head-to-tail, resulting in the formation of infinite tooth-like chains. The different structures of complexes 3 and 5 may be attributed to the different solvent molecules included. [Copyright &y& Elsevier]

Abstract: Using mixed ligands and hydrothermal reactions, five new coordination polymers, [Co(o-CCA)(bpe)(H2O)] n ·0.25nCH3OH (1), [Ni(o-CCA)(bpe)(H2O)] n ·0.5nH2O (2), [M(p-CCA)(bpe)1.5(H2O)] n · nH2O (M=Co, (3); Ni, (4)) and [Co(o-BDC)(bpe)(H2O)] n · nH2O (5) (H2CCA=carboxycinnamic acid; bpe=1,2-bis(4-pyridyl)ethane; o-H2BDC=1,2-benzenedicarboxylic acid) were obtained. Complexes 1–4 possess complicated 3D metal-organic frameworks, but different position of functional dicarboxylate groups results in different architecture, forming diversity of structures. 1 and 2, 3 and 4 are isomorphous, respectively, in which solvent molecules are clatharated. When o-BDC instead of CCA was used, complex 5 was obtained, which is of (4,4) 2D grid-like layers with cavities. Thermal stabilities of complexes 1–4 were discussed. [Copyright &y& Elsevier]

Abstract: A new photoresponsive D-π-A dye, N-octadecyl-4-{2-[4-(2-(4-N,N-dimethylaminophenyl)azo)phenyl]ethenyl}pyridinium iodide (AEP) containing both CHce:glyph name="dbnd" />N bonds, was synthesized, and N-octadecyl-4-[2-(4-N,N-dimethylaminophenyl)azo]pyridinium iodide (AP) and N-octadecyl-4-[2-(4-N,N-dimethylaminophenyl)ethenyl] pyridinium iodide (EP) were also synthesized for comparison. The photoelectric conversion (PEC) properties of the dye Langmuir–Blodgett (LB) monolayer films modified indium-tin oxide (ITO) electrode deposited under 20mNm−1 of surface pressure were studied. The results show that AEP exhibits better PEC properties than AP and EP do. The photoelectric conversion efficiency is 0.31% for AEP in 0.5molL−1 KCl electrolyte solution under ambient condition, while those for AP and EP are 0.14 and 0.23% under the same conditions, respectively. [Copyright &y& Elsevier]

Abstract: Two new mixed-ligands lanthanide coordination polymers, [Ln(Ac)(ip)(H2O)2]·0.5H2O (Ln=La (1); Ln=Eu (2); Ac=acetate; ip=isophthalate) have been synthesized under hydrothermal condition. Single-crystal X-ray analyses show that complexes 1 and 2 are three-dimensional structure in which lanthanide ions are bridged by monocarboxylate ligand, acetate or dicarboxylate ligand, isophthalate. And the central lanthanide ions, La3+ and Eu3+, are both nine-coordinate with oxygen atoms. The thermogravimetric analysis was carried out to examine the thermal stability of the title complexes. And the photoluminescence property of complex 2 was also investigated. [Copyright &y& Elsevier]

Abstract: Three new lanthanide coordination polymers with 1,2,4,5-benzenetetracarboxylic acid, Pr2(betc)2(4,4′-bpyH2)·0.25H2O (1), Ln2(betc)2(4,4′-bpyH2) (Ln=Eu (2), Gd (3)) were hydrothermally prepared. The crystallographic data of 1–3 show that they are isostructural, and possess 3D framework with 1D rhomboid channels, where the 4,4′-bipyridine molecules exist steadily via hydrogen bonds. Meanwhile, a supramolecular structure of (4,4′-bpyH2)2(betc) (4) was also obtained by hydrothermal reaction. The results of 1–4 indicate that 4,4′-bipyridine molecule acting as a template plays an important role in the formation of complexes 1–3, and thus has a synergistic action in the construction of 3D framework with large channels. [Copyright &y& Elsevier]

First examples of lanthanide coordination polymers with 4,4′-biphenyldicarboxylic acid (4,4′-H2bpdc), Ln(4,4′-Hbpdc)(4,4′-bpdc)(H2O)2 (Ln=Pr(1), Eu(2), Gd(3)) and Er(4,4′-bpdc)1.5(H2O)2 (4) were prepared by the solvothermal synthesis. Crystallographic data show that complexes 1–3 are isostructural and each lanthanide(III) ion is coordinated to six 4,4′-Hbpdc ligands, and display 3D sandwich structure with lanthanide ion layers and organic ligand layers alternately linking up with each other. Complex 4 shows different coordination modes of 4,4′-bpdc ligands from 1–3 and each Er(III) ion is attached to four 4,4′-bpdc ligands to construct 3D sandwich structure. The emission spectrum of 2 shows one Eu3+ ion site, which is consistent with the results of the X-ray crystal structure analysis. [Copyright &y& Elsevier]

This paper presents three new lanthanide coordination polymers [Pr2(pim)3(phen)2(H2O)]n·3nH2O (1) (H2pim=pimelic acid; phen=1,10-phenanthroline) and [Ln(Hpim)(pim)(phen)]n·1.5nH2O (Ln=Nd, 2; Er, 3) prepared by the hydrothermal reaction. The structural details of complexes 1, 2 and 3 are reported. In complex 1, the Pr(III) ions are bridged by pim in three modes to form 2D layers. Adjacent layers are assembled by hydrogen bonds and π–π stacking between phen ligands into a 3D network. In complex 2, the Nd(III) ions are connected by pim and Hpim in two modes into 1D chains. Hydrogen bonding and π–π stacking between chains result in a 3D supramolecular structure. Single crystal X-ray diffraction analysis shows that complex 3 is isostructural with complex 2. [Copyright &y& Elsevier]

Reported herein are the hydrothermal synthesis and crystal structures of four lanthanide coordination polymers with nitrilotriacetic acid (H3NTA) [Ln(NTA)(H2O)]n (Ln=La, 1; Pr, 2; Nd, 3; Eu, 4). Despite similar syntheses, compounds 1 to 4 show transformation in coordination mode of NTA and coordination number of Ln3+ duo to lanthanide contraction. The Ln(III) ions in 1 and 2 are nine-coordinated and connected through octadentate bridging ligands (NTA) to form a three-dimensional network. The Ln(III) ions in 3 and 4 are eight-coordinated and bridged by heptadentate bridging ligands (NTA) to form an extended two-dimensional layer structure, which further construct a three-dimensional supramolecular structure via coordination bond and three-centered hydrogen bonding between adjacent layers. [Copyright &y& Elsevier]

Three novel amphiphilic 1,10-phenanthroline derivatives, 2-(4'-octadecyloxyphenyl)imidazo[4,5-f]1,10-phenanthroline (5), 2-(3'-methyloxy-4'-octadecyloxyphenyl)imidazo[4,5-f]1,10-phenanthroline (6), and 3-octadecyl-2-(4'-dimethylaminophenyl)imidazo [4,5-f]1,10-phenanthroline (7) were synthesized via a facile, two-step procedure. [ABSTRACT FROM AUTHOR]

Three lanthanide coordination polymers were prepared by hydrothermal synthesis and characterized by single-crystal X-ray diffraction. [Pr2(mBDC)3(phen)(H2O)]n·0.5nH2O (1) (mBDC=isophthalate, phen=1,10-phenanthroline) exhibits two kinds of metal environments (coordination numbers 7 and 8). In complex 1, mBDC ligands adopt the tetradentate (bridging and bridging) coordination mode and connect Pr ions into an undulating layer, and a 3D supramolecular structure is formed via hydrogen bonds between adjacent layers. [Tb4(mBDC)6(phen)]n (2) has three types of metal environments (coordination numbers 6, 7 and 8) and is composed of a 3D network formed by mBDC linking Tb ions via tetradentate (bridging and bridging) and pentadentate (bridging/chelating and bridging) coordination modes. There are two kinds of small quadrilateral channels along the a-axis. [Er4(mBDC)6(phen)]n (3) is isostructural to complex 2. [Copyright &y& Elsevier]

Two polymeric complexes, [Nd2(bdc)2(Hbdc)2(H2O)]n·nH2O (1) and [Nd2(bdc)3(phen)(H2O)]n·nH2O (2) (H2bdc=isophthalic acid; phen=1,10-phenanthroline) were synthesized and characterized by IR spectra, TGA, and X-ray crystallography. In complex 1, the Nd(III) ions are bridged by bdc2− and Hbdc− in three modes to form a two-dimensional layer. Adjacent layers are linked by hydrogen bonds composed of coordinated and lattice water molecules, together with carboxylate groups, forming a three-dimensional network. In complex 2, the Nd(III) ions are connected by bdc2− ligands in three modes into a two-dimensional layer. Weak C&z.sbnd;H⋯O hydrogen bonding interactions between the chelated phen ligands and the carboxylate O atoms across adjacent layers result in a three-dimensional network. [Copyright &y& Elsevier]

The first series of lanthanide coordination polymers with glutarate (glu) and 1,10-phenanthroline (phen), [Nd2(glu)3(phen)2]n 1, [Tb(glu)(phen)Cl]n 2 and [Ho(glu)(phen)Cl]n 3, have been prepared by hydrothermal reaction and characterised by IR spectra and X-ray crystallography. In complex 1, there are two different conformations for glutarate ligands, the gauche- and anti-forms. Nd(III) ions are bridged by glutarate ligands in three modes to form 2D layer structure. Phen ligands coordinate to Nd(III) ions in chelating mode and protrude from the polymeric layer in two different directions. Two types of π–π interactions exist between two adjacent layers. In complex 2, Tb(III) ions are connected by glutarate ligands into 1D chain structure. Phen ligands coordinate to Tb(III) ions in chelating mode and locate at both sides of the chain. The C–H⋯O, C–H⋯Cl weak hydrogen bonds and π–π stacking interactions between chains result in 3D supramolecular structure. Single-crystal X-ray diffraction analysis shows that complex 3 is isostructural with complex 2. [Copyright &y& Elsevier]

[Eu(ABA)(phen)2(H2O)3](ClO4)3·3phen·4.5H2O (1) and [Eu(Val)(phen)2(H2O)3](ClO4)3·3phen·2H2O (2) are two new europium complexes with amino acids and 1,10-phenanthroline (phen=1,10-phenanthroline, ABA=α-amino butyl acid, Val=l-valine). Their crystal structures were measured by X-ray crystallography. Europium atoms in both complexes are nine-coordinated with bidentate 1,10-phenanthroline and carboxylate anion of amino acids, and water molecules. In the solid state, 1 and 2 have a structure involving aromatic stacking of the coordinated and non-coordinated 1,10-phenanthroline and the oxygen atoms of non-coordinated perchlorate anions being H-bond acceptors connect [Eu(ABA)(phen)2(H2O)3]3+·3phen·4.5H2O or [Eu(Val)(phen)2(H2O)3]3+·3phen·2H2O in their structures. In their interactions, several C–H⋯O bonds play an important role. Owing to their different amino acid ligands and the number of lattice water molecules, there is some difference in their hydrogen bond patterns in 1 and 2. The side chain of l-valine is involved in the formation of C–H⋯O bonds. Hydrogen bond and π–π interactions determine the supramolecular formation of three-dimensional net works of both complexes. [Copyright &y& Elsevier]

Two novel ligands, 2-(4′-dimethylaminophenyl)imidazo[4,5-f]1,10-phenanthroline (L1) and 3-ethyl-2-(4′-dimethylaminophenyl)imidazo[4,5-f]1,10-phenanthroline (L2), and their europium(III) complexes with dibenzoylmethanate (DBM), Eu(DBM)3(L1) and Eu(DBM)3(L2), were synthesized and characterized by IR, UV–Vis and fluorescence spectroscopy, and thermogravimetric and differential thermal analyses (TG–DTA). The fluorescent intensity of Eu(DBM)3(L2) is 18 times that of Eu(DBM)3(L1). The crystal structures of Eu(DBM)3(L1) and L2 were determined by single crystal X-ray diffraction. Each europium atom is coordinated by six oxygen atoms of three bidentate DBM anions and two nitrogen atoms from one bidentate L1, forming a distorted square antiprism. Highly resolved fluorescence spectroscopy of Eu(DBM)3(L1) at 77 K revealed one Eu(III) site. [Copyright &y& Elsevier]

Three AIE (aggregation-induced emission)-ESIPT (excited-state intramolecular proton transfer) active 2-(2-hydroxyphenyl)benzothiazole derivatives, HL1, HL2 and HL3 with one, two and three rotatable phenyl groups, were obtained and characterized. Their AIE properties in THF/HEPES solution were investigated in detail. HL2 shows the best AIE performance with 71-fold fluorescence enhancement, while HL3 only shows a 9-fold enhancement. With the AIE property, HL1 and HL2 could act as fluorescence chemosensors to detect Cu2+ ions via the "turn off" mode in THF/HEPES media. With the ESIPT property, HL1 and HL2 could also detect Zn2+ ions via the "turn on" mode in EtOH/HEPES media. During the detection process, both demonstrate rapid response and high contrast before and after the addition of metal ions. The species formed in the detection system were investigated. The results of X-ray single-crystal diffraction confirm that Zn2+ is coordinated with the oxygen atom and Schiff base nitrogen atom instead of the benzothiazole nitrogen atom in the tetrahedron geometry. Moreover, the chemosensors were successfully constructed into handy fluorescence test papers for Cu2+ and Zn2+ detection. [ABSTRACT FROM AUTHOR]

A multi-binding site chemosensor, N-(3-methoxy-2-hydroxybenzylidene)-3-hydroxy-2-naphthahydrazone (H3L), with excited-state intramolecular proton transfer (ESIPT) behaviour was prepared and characterized. It possesses no aggregation-induced emission (AIE) characteristics but can detect Cd2+ and Zn2+ ions selectively in the "off–on" mode based on the AIE of their complexes in the media of THF/HEPES and THF/H2O, respectively, which will provide a new strategy for target detection based on AIE. The detection limits of Zn2+ and Cd2+ were 9.85 × 10−9 M and 1.27 × 10−7 M, respectively. The aggregates of the complexes formed in the detection system were confirmed by DLS data and SEM images. The corresponding Zn2+ (1) and Cd2+ (2) complexes were prepared to investigate the response mechanism. Powder X-ray diffraction and single crystal X-ray diffraction proved that complex 1 is the species formed in the detection system. The chemosensor coordinates with the Cd2+ and Zn2+ ions in different formation and coordination modes, leading to the emission position of the aggregates at 560 and 645 nm, respectively, based on which Cd2+ ions were successfully differentiated from Zn2+ ions. Moreover, the detection of Cd2+ and Zn2+ ions was realized qualitatively via test paper and quantitatively in water. [ABSTRACT FROM AUTHOR]

An acylhydrazone-based derivative, 3-hydroxy-N'-(2-hydroxy-1-naphthalene methylene)-2-naphthalene hydrazide (H 3 L), was synthesized and characterized by elemental analyses, IR, 1 H NMR and mass spectrum. H 3 L is non-fluorescent in DMSO. But the fluorescence emission is enhanced obviously via the formation of aggregates in DMSO/H 2 O mixture. The formed aggregates were confirmed by DLS and SEM. H 3 L is an aggregation-induced emission (AIE)-active fluorophore. H 3 L can act as a fluorescence sensor for Al 3+ and Zn 2+ in DMSO/H 2 O (v/v, 9/1) and THF/H 2 O (v/v, 999/1), respectively. And H 3 L is also a naked-eye probe for Fe 3+ in DMSO/H 2 O (v/v, 9/1). The binding stoichiometry of H 3 L to both Al 3+ and Zn 2+ is 1:1, but that to Fe 3+ is 2:1. The metal complex species formed in the detection procedure are deduced by Job plot, spectroscopic titrations and ESI–MS to be [AlL(DMSO) 2 ], [Zn(HL)(H 2 O)] and [Fe(HL)(H 2 L)]. The detection limit is as low as 3.66 μM for Al 3+ , 1.01 μM for Zn 2+ and 0.34 μM for Fe 3+ . H 3 L can also be used to detect intracellular Al 3+ and Zn 2+ . The sensing event might be attributed to a combinational effect of excited state intramolecular proton transfer (ESIPT) and chelation-enhanced fluorescence (CHEF) mechanism for selective detection of Al 3+ and Zn 2+ ions, and ligand-metal charge transfer (LMCT) mechanism for Fe 3+ ion. [ABSTRACT FROM AUTHOR]

A new fluorescent sensor 6-(2,3-dihydroxyphenyl)-5,6-dihydrobenzoimidazo[1,2-c] quinazoline (H 2 L) and the Zn(II) complex [Zn 2 L 1 2 ]∙C 2 H 5 OH (H 2 L 1 = 3-{[2-(1 H -benzoimidazol-2-yl)-phenylimino]-methyl}-benzene-1,2-diol) ( 1 ) were synthesized and characterized by single-crystal X-ray diffraction. H 2 L can be used to recognize Cu 2+ in aqueous media as an on–off fluorescent sensor, forming the Cu(II) Schiff-base complex (CuL 1 ). Furthermore, CuL 1 can serve as an off–on fluorescent sensor to detect histidine (His) via the ligand displacement approach. The sequential detection of Cu(II) and histidine shows on–off–on phenomenon. The crystal structure of the dinuclear Zn(II) complex indicates that the coordination of H 2 L with Zn(II) promotes C N bond breakage, resulting in the quinazoline ring-opening of H 2 L to form the Zn(II) Schiff-base complex ( 1 ). The experimental results proved that H + can also assist the ring-opening of H 2 L to form a Schiff base, H 2 L 1 . H 2 L is stable in neutral and weak basic solutions. This is further confirmed by the theoretical calculations. The cell imaging studies indicated that H 2 L and CuL 1 can be used to detect the intracellular Cu 2+ ion and His under physiological conditions, respectively. CuL 1 can also be used to determine His in urine. [ABSTRACT FROM AUTHOR]

The compounds of 3-aminopyridine-2-carboxylic acid with K+ (1) and Zn2+ (2) were found to be AIE-active. The AIE behaviours could be attributed to the restriction of intramolecular rotation (RIR) and vibration (RIV) via hydrogen bonds, resulting in rigidity enhancement of the molecules. An AIE-based fluorescence turn on chemosensor for the Zn(ii) ion has been developed in aqueous media with high selectivity and sensitivity. [ABSTRACT FROM AUTHOR]

A chemosensor 3-[(2-hydroxybenzylidene)-amino]-1H-pyridin-2-one (HL) for multi-ions was synthesized and characterized by single-crystal X-ray diffraction. HL is a turn-on fluorescence chemosensor for Al 3+ , F − , and CN − ions in DMSO. F − and CN − anions could be further distinguished by the ratiometric absorption spectrometry method. Job plot and 1 H NMR data showed that the binding stoichiometries of HL with Al 3+ , F − , or CN − all were 1:1. Further observations of 1 H NMR titration and ESI-MS showed that the possible fluorescent species of Al 3+ with HL was [AlL(OH)(DMSO) 2 ] + in DMSO. The spectroscopic observations of the Al(III) complex showed that the two oxygen atoms and one imine nitrogen atom of HL were coordinated to the Al(III) ion. While the crystal structure of the Ni(II)-L complex confirmed the tridentate coordination mode of HL in the complexes. The experimental results revealed that HL and F − ion formed hydrogen bond in DMSO, while CN − attacked the carbon atom at –C N of HL to undergo a nucleophilic addition. The theoretical calculations confirmed that HL showed very weak fluorescence because of the excited-state intramolecular proton transfer (ESIPT). The turn-on sensing of HL to Al 3+ , F − , and CN − ions arose from the inhibition of ESIPT. MTT tests showed that HL was low toxic to cells. Also, HL could probe intracellular Al 3+ and F − ions by bioimaging. [ABSTRACT FROM AUTHOR]

A quinazoline-based fluorescence chemosensor, 6-phenol-2-yl-(5,6-dihydrobenzimidazo[1,2-c])quinazoline (HL), for highly selective recognition of Cu(ii) in aqueous media was synthesized. The detection limit was of the order of 10−6 M. The crystal structures of the Cu(ii) and Cd(ii) complexes showed that HL changed to a Schiff base when it reacts with metal salts and that the metal ions coordinate with two nitrogen atoms and one hydroxyl oxygen atom from the Schiff base. The theoretical calculations at B3LYP-SCRF/6-31G(d) confirmed that it is the Cu(ii) ion that assisted the ring-opening of the quinazoline derivative, forming a Cu(ii) Schiff base complex during the detection. LMCT leads to the disappearance of fluorescence. A cell imaging study indicated that HL could be used to detect the intracellular Cu2+ ion. [ABSTRACT FROM AUTHOR]

Self-assembly of Ca 2+ , Zn 2+ and 4,5-imidazoledicarboxylic acid (H 3 imdc) via hydrothermal conditions under controlled pH affords three new and unusual heterometallic metal–organic frameworks (MOFs): [Ca 2 Zn 2 (imdc) 2 (Ac)(OH)(H 2 O)] ( 1 ), [CaZn 2 (imdc) 2 (im) 2 (H 2 O) 2 ]·1.8H 2 O ( 2 ), [CaZn(Himdc) 2 (H 2 O)] ( 3 ), (Ac = acetate; im = imidazole) and characterized by elemental analysis, IR, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction. X-ray single-crystal structural analyses revealed that Zn(II) ions all coordinate with two imdc ligands no matter whether it is in a five or six coordination environment, while Ca(II) ions in 1 – 3 are all eight-coordinated. The Zn(II) ion with imdc ligands makes up a 2-D layer in 1 , 1-D chain in 2 , and 0-D elongated bridge in 3 , respectively, which further connected the Ca(II) ion with the carboxylate oxygen atoms to form 3-D MOFs in 1 , 2 , a 2-D framework in 3 . The total Schäfli symbol of the topologies of the heterometallic complexes 1 – 3 are {4;6 2 }{4;6 4 ;8}{4 2 ;6 3 ;8 5 }{4 3 ;6 2 ;8}{4 4 ;6 4 ;8 2 }{4 4 ;6 5 ;8 5 ;10}{4}{6 2 ;8}, {12 3 }{12} 2 {4;12 2 }{4;12 5 } and {4;8 2 }{4 2 ;6;8 2 ;10}{4 6 ;6 4 }{8}, respectively. The three Ca(II)/Zn(II) heterometallic complexes showed blue emission arising from intraligand π–π ∗ transition. [ABSTRACT FROM AUTHOR]

Six d 10 complexes, [Zn1.5(stp)(bpy)0.5(H2O)2]·0.5H2O (1), Cd1.5(stp)(bpy)0.5(H2O)2 (2), [Cd1.5(stp)(bpy)(H2O)]·H2O (3), [Zn0.5(bpy)0.5(H2O)2][Zn(stp)(bpy)(H2O)]·0.5H2O (4), Cd3(stp)2(bpy)3(H2O)3 (5), Hbpy·[Zn0.5(bpy)(H2O)2][Zn0.5(stp)(H2O)]·H2O (6) based on 2-sulfoterephthalate (stp3−) and 4,4′-bipyridine (bpy) have been synthesized under hydro/solvo-thermal conditions and structurally characterized. Complex 1 exhibits a three-fold interpenetrated 3D porous architecture. Complexes 2 and 3 possess helices with different chirality arranging alternately. 4 and 6 are addition compounds, which compose of complex cation and complex anion. Complex 5 features a 3D layer-pillar framework in which a (4, 4) grid layer is constructed by stp3− ligands and Cd(II) ions, and the layers are further connected by bpy pillars. The solid-state luminescent properties of the coordination polymers have also been investigated. [ABSTRACT FROM AUTHOR]

Abstract: A new Schiff base 1-[(1H-1,2,4-triazole-3-ylimino)-methyl]-naphthalene-2-ol (H2L) exhibiting high selectivity for Al3+ ion over other metal ions, such as Li+, Na+, K+, Ca2+, Mg2+, Cu2+, Co2+, Mn2+, Ni2+, Zn2+, Cd2+, Pb2+, Fe3+, and Cr3+ was prepared, and it is sensitive for Al3+ with the detection limit reaching 0.69μM in DMF. Upon addition of Al3+, the significant enhancement (32-fold) of fluorescence intensity for H2L at 466nm is ascribed to the formation of a 1:1 complex between Al3+ and H2L, which is denoted as the chelation-enhanced fluorescence (CHEF) effect. The confocal fluorescence microscopy experiments demonstrate that H2L could be used as a fluorescent probe for Al3+ in living cells. [Copyright &y& Elsevier]

Four new three-dimensional isostructural lanthanide-cadmium metal-organic frameworks (Ln-Cd MOFs), [LnCd2(imdc)2(Ac)(H2O)2]⋅H2O (Ln=Pr ( 1), Eu ( 2), Gd ( 3), and Tb ( 4); H3imdc=4,5-imidazoledicarboxylic acid; Ac=acetate), have been synthesized under hydrothermal conditions and characterized by IR, elemental analyses, inductively coupled plasma (ICP) analysis, and X-ray diffraction. Single-crystal X-ray diffraction shows that two LnIII ions are surrounded by four CdII ions to form a heteronuclear building block. The blocks are further linked to form 3D Ln-Cd MOFs by the bridging imdc3− ligand. Furthermore, the left- and right-handed helices array alternatively in the lattice. Eu-Cd and Tb-Cd MOFs can emit characteristic red light with the EuIII ion and green light with the TbIII ion, respectively, while both Gd-Cd and Pr-Cd MOFs generate blue emission when they are excited. Different concentrations of Eu3+ and Tb3+ ions were co-doped into Gd-Cd/Pr-Cd MOFs, and tunable luminescence from yellow to white was achieved. White-light emission was obtained successfully by adjusting the excitation wavelength or the co-doping ratio of the co-doped Gd-Cd and Pr-Cd MOFs. These results show that the relative emission intensity of white light for Gd-Cd:Eu3+,Tb3+ MOFs is stronger than that of Pr-Cd:Eu3+,Tb3+ MOFs, which implies that the Gd complex is a better matrix than the Pr complex to obtain white-light emission materials. [ABSTRACT FROM AUTHOR]

Three novel isostructural lanthanide(III) coordinationpolymers(LnCPs), {[Ln3(bidc)4(phen)2(NO3)]·2H2O}n(Ln= Gd (1), Eu (2), Tb (3); H2bidc = benzimidazole-5,6-dicarboxylic acid, and phen = 1,10-phenanthroline),were synthesized via hydrothermal reaction and characterized. Thecomplexes crystallize in the chiral space group P212121. They possess 1D structuresbased on lanthanide trinuclear clusters containing Ln(1)O9, Ln(2)O6N2, and Ln(3)O6N2polyhedra by bidc linkers, and phen and nitrate act as terminalligands. The bidc and phen ligands provide efficient energy transferfor the sensitization of Eu(III) and Tb(III) complexes. The complexes 2and 3emit red and green light, respectively.Lifetimes and quantum yields of luminescence are 0.86 ms and 13.20%for 2and 0.32 ms and 2.08% for 3. Tuningof white-light emission by adjusting the doping concentration of Eu(III)and Tb(III) ions in the Gd(III) complex was achieved. [ABSTRACT FROM AUTHOR]

Self-assembly of copper(ii) ion, 3,4-pyridinedicarboxylate (PDC), and 1,10-phenanthroline (phen) under basic conditions at 100 °C affords four PDC linked copper(ii) complexes, [Cu4(μ2-OH)3(μ3-OH)(PDC)(phen)4]n·n(PDC)·11.5nH2O (1), [Cu4(μ2-OH)2(μ3-OH)2(PDC)(phen)4]n·n(PDC)· 11.5nH2O (2), [Cu8(μ2-OH)2(μ3-OH)6(PDC)2(phen)8]·2(PDC)·23H2O (3), and [Cu3.5(μ2-OH)3(PDC)2(phen)]n(4). 1–4are copper hydroxo complexes, and 1, 2and 3co-crystallized from the one-pot reaction. X-ray single crystal diffraction analyses indicate that complexes 1and 2are linkage isomers and contain tetranuclear copper cluster cores with different geometry, and that PDC links the cluster core to form a one-dimensional chain. Complex 3is a discrete step-like octanuclear copper hydroxo cluster complex. The involvement of hydroxo and phen in the coordination makes some coordination sites of PDC idle, which leads to rich hydrogen bonds and π–π interactions in complexes 1, 2and 3. Complex 4contains two types of copper hydroxo cluster cores: chair-like tetranuclear and linear trinuclear units, and the cluster cores are linked by PDC to a double-layer metal–organic framework. Magnetic properties of 1, 3and 4were investigated. The results reveal that complexes 3and 4exhibit strong antiferromagnetic interactions whereas ferromagnetic coupling is predominant for complex 1. The magnetic properties are analyzed in connection with their structures. [ABSTRACT FROM AUTHOR]

Abstract: Three new lanthanide coordination polymers based on mixed acid ligands [Ln(oba)(ox)0.5(H2O)2] n (Ln=Y (1); Er (2); Yb (3). H2oba=4,4′-oxybis (benzoic acid); H2ox=oxalic acid) were prepared by hydrothermal reactions and characterized by single-crystal X-ray diffraction. In these complexes, lanthanide ions are bridged by oba ligands to form 1D double-stranded chains, which are further connected by ox ligands, resulting in the formation of 2D (4,4) grids. The upconversion emission of the Y:Er–Yb co-doped coordination polymer was studied and the unusual blue emission for the Er(III) complexes was observed, which arises from the 2H9/2 → 4I15/2 transition and can be explained by three-photon excitation mechanism which is mostly phonon-dependent. The introduction of the oxalate anion without high-energy vibrational groups is beneficial to the increasing intensity of upconversion fluorescence. The magnetic properties of complexes 2 and 3 were investigated. The decrease of χ M T over the temperature range of 300–2K and the negative value of θ are due primarily to the splitting of the ligand field of the ErIII and YbIII ions together with the possible weak antiferromagnetic coupling between the rare earth ions. [Copyright &y& Elsevier]

Abstract: Fluorescence of terbium(III) is sensitized when excited in the presence of ciprofloxacin (CPLX) in the aqueous solution because a Tb(III)–CPLX complex is formed and the maximum fluorescence peak locates at 545nm. The second-order scattering (SOS) peak at 545nm also appears for the Tb(III)–CPLX complexes with the excitation wavelength of 272nm. The intensity at 545nm obviously increases when the silver nanoparticles are added to the Tb(III)–CPLX system, and the relative intensity is proportional to the concentration of CPLX. Based on this phenomenon, a new method for the determination of CPLX has been developed by using a common spectrofluorometer to measure the intensity of fluorescence and SOS. The intensity is enhanced most by silver nanoparticles at pH 6.0. The calibration graph for CPLX is linear in the range of 3.0×10−9 to 1.0×10−5 moll−1. The detection limit is 8.5×10−10 moll−1. The method was applied satisfactorily to the determination of CPLX in tablets and capsules. The results show that silver nanoparticles with certain size and concentration can enhance the fluorescence and SOS intensity of the system. [Copyright &y& Elsevier]

Abstract: Six new complexes: [Ln2(pzda)3(H2O)2]·2.5H2O (Ln=Nd, (1); Eu, (2)), [Co(pzda) (bpe)]·0.125(bpe)·1.75H2O (3), [Mn(pzda)(H2O)1.5] (4), [Co2(pzda)2(bpe)(H2O)4]·0.5(CH3OH)·H2O (5) and [Co(pzda)(2,2′-bpy)(H2O)]·0.5H2O (6) (H2pzda=pyrazine-2,6-dicarboxylic acid, bpe=1,2-bis(4-pyridyl)ethane, 2,2′-bpy=2,2′-bipyridine) were obtained from metal salts and H2pzda under hydro(solvo)thermal conditions. The single crystal X-ray structural analysis reveals that the title complexes have different structures, ranging from zero- to three- dimensions, which are mainly due to the different metal ions, and especially the coordination modes of the pzda ligands. Complexes 1 and 2 have 3D metal-organic frameworks containing a 1D tri-strand array, in which the pzda ligand adopts a pentadentate mode to link lanthanide ions. Complex 3 has a 2D metal-organic framework, in which the pzda ligand acts in a tetradentate mode to connect Co(II) ions into 1D chains, which are further connected by bpe spacers into a 2D framework. While in 4, both of the two carboxylate groups of the pzda ligand adopt μ2-O bridging modes to link Mn(II) ions into a 1D coordination polymer, which is further assembled into a 2D supramolecular network containing double-stranded hydrogen-bonded helical chains. In both 5 and 6, the pzda ligand binds metal ions as a tridentate ligand (ONO mode) to form zero dimensional structures. Complex 5 is a binuclear molecule, while 6 is a mononuclear complex, which can be attributed to the bridging ligand bpe for 5 and the terminal auxiliary ligand 2,2′-bpy for 6. [Copyright &y& Elsevier]

Abstract: Four new Cu(II) complexes [Cu(pzda)(2,2′-bpy)(H2O)]·2.5H2O (1), [Cu(pzda)(phen)(H2O)]·H2O (2), [Cu(pzda)(4,4′-bpy)]·H2O (3) and [Cu(pzda)(bpe)0.5(H2O)] (4) were synthesized by hydrothermal reactions of copper salt (acetate or sulphate) with pyrazine-2,6-dicarboxylic acid (H2pzda), and 2,2′-bipyridine (2,2′-bpy), 1,10-phenanthroline (phen), 4,4′-bipyridine (4,4′-bpy) or 1,2-bis(4-pyridyl)-ethane (bpe), respectively. For 1 and 2, they are both monomeric entities which are further assembled into 3D supramolecular networks by hydrogen bonds and π–π stacking interactions. Complex 3 has a 2D metal–organic framework which is connected into 3D supramolecular network by hydrogen bonds. However, for 4, the bpe ligand bridges two Cu(II) ions into binuclear unit, and then the binuclear molecules are assembled into 3D supramolecular network by hydrogen bonds between the coordination water molecule and the carboxylate oxygen atoms. The thermal decomposition mechanism of complexes 1 and 2 cooperated with powder XRD at different temperatures is discussed. The results reveal that once liberation of water molecules takes place the supramolecular network of 1 and 2 collapses. [Copyright &y& Elsevier]

Abstract: Three complexes [Mn(pzda)(H2O)2] n (1), [Mn(pzda)(bpy)] n (2) and [Mn(pzda)(phen)(H2O)2] (3) (H2pzda=pyrazine-2,6-dicarboxylic acid, bpy=2,2′-bipyridine, phen=1,10-phenanthroline) were synthesized by the hydro(solvo)thermal reaction and characterized by single crystal X-ray diffraction, elemental analysis, IR spectrum. Complex 1 is a 2D bilayer structure in which each Mn(II) ion is coordinated to two oxygen atoms and two nitrogen atoms from three pzda ligands and two oxygen atoms of two water molecules. Complex 2 is a 3D metal-organic framework structure. Mn(II) is seven-coordinated: four oxygen atoms and one nitrogen atom from three pzda ligands and other two nitrogen atoms from one bpy molecule, displaying a distorted pentagonal bipyramid geometry. While complex 3 is a mononuclear structure in which Mn(II) ion is seven-coordinated to one pzda, one phen, and two water molecules. The complex is connected into a 3D supramolecular network via hydrogen-bonding and π–π stacking interactions. In each of complexes 1–3, pzda ligands adopt different coordination mode. [Copyright &y& Elsevier]

A surfactant ion-pair complex, [Ru(bpy)2L][Eu(NTA)4]2 (in which L = 1-docosyl-2-(2- pyridyl)benzimidazole, bpy = 2,2'-bipyridine, and NTA = 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedionato) has been synthesized. The surface pressure−area isotherm measurements show that the complex forms a stable Langmuir film at the air−water interface without adding any electrolytes into the subphase. The monolayers formed at the surface pressures of 5 mN m-1 and 20 mN m-1, have been successfully transferred onto glass and quartz substrates with the transfer ratios close to unity. The Langmuir−Blodgett films were studied by UV−visible, infrared, and emission spectroscopies, atomic force microscopy, and cyclic voltammetry. The optical, redox, and morphology properties of the LB films were found to be significantly affected by the target surface pressures used for the film depositions. [ABSTRACT FROM AUTHOR]

Abstract: Porous lanthanide coordination polymers, {[Ln2(atpt)3(H2O)2]·0.5(4,4′-bpy)(H2O)} n [Ln=Eu(1), Gd(2), Yb(3), H2atpt=2-aminoterephthalic acid, 4,4′-bpy=4,4′-bipyridine] were obtained by hydro-solvothermal reaction, in which 4,4′-bpy acts as template. For the first time the nitrogen atom of an atpt ligand coordinates to metal ions in 1–3. The photophysical properties and thermal stability of 1 were investigated. [Copyright &y& Elsevier]

Abstract: Five new supramolecular lanthanide coordination polymers with three different structures, {[La2(IA)3(phen)2]·2H2O} n (1), {[Ln(IA)1.5(phen)]· xH2O} n [x =1, Ln=Eu (2); x =0.25, Ln=Dy (3)], and [Ln(IA)1.5(phen)] n [Ln=Er (4); Yb (5)], were prepared by hydro- and solvothermal reactions of lanthanide chlorides with itaconic acid (H2IA) and 1,10-phenanthroline (phen), and structurally characterized by single crystal X-ray diffraction. 1 Comprises 1-D double-chains that are further assembled to a 3-D supramolecular structure via hydrogen bonds and π–π stacks between phen molecules. 2 and 3 have 2-D infinite networks which are further constructed to form 3-D supramolecular architectures with 1-D channels by π–π aromatic interactions. 4 and 5 have 2-D layer structures consisting of three types of rings which are further architectured to form 3-D supramolecular structures by C–H⋯O hydrogen bonds. The H2IA ligands are all completely deprotonated and exhibit tetra-, penta-, and hexadentate coordination modes in the titled complexes. The high-resolution emission spectrum of 2 shows only one Eu3+ ion site in 2, which is in agreement with the result of X-ray diffraction. And the magnetic property and the thermal stability of 2 were also investigated. [Copyright &y& Elsevier]

Abstract: Three new polynuclear lanthanide coordination polymers [Ln5(μ3-OH)(oba)7(H2O)2] n ·0.5nH2O (Ln=Eu (1), Ho (2)) and [Yb6(oba)9(H2O)] n (3) (H2oba=4,4′-oxybis(benzoic acid)), were prepared by hydrothermal reactions. 1 and 2 are isomorphous and exhibit complicated three-dimensional structures based on [Ln5(μ3-OH)(oba)7(H2O)2] building blocks. In the asymmetric unit, there are five different coordination environments of Ln(III) ions, including a trinuclear hydroxo core. Complex 3 is a three-dimensional coordination polymer built up from a hexanuclear building block. In 3, Yb(III) ions have six different chemical environments and are in a regular arrangement, resulting in pseudohexagonal prisms along the a-axis. The luminescent property of 1 and magnetic behaviors of 2 and 3 have also been studied. [Copyright &y& Elsevier]