Syntheses,structures and luminescence of three copper(I) cyanide coordination polymers incorporating flexible N-donor ligands

Three copper(I) cyanide coordination polymers, namely [Cu₈(CN)₈(btmb)₂]_n (1), [Cu(CN)(btmb)_0.5]_n (2) and [Cu₂(CN)₂(dpa)]_n (3) (btmb = 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene, dpa = di(4-pyridyl)amine), were synthesized under hydrothermal conditions and characterized by elemental analyses, IR spectra, PXRD and thermogravimetric analyses. Single-crystal X-ray diffraction analyses reveal that complex 1 is an interesting 2D double-layered network constructing from eight distinct Cu(I) centers, eight μ₂-cyanides and two tetradentate cis-btmb ligands. Complex 2 is a ladder-like coordination polymer assembled by CuCN linear chain and bidentate trans-btmb linker. Complex 3 has a 2D wave-like network constructing from CuCN zigzag chain and V-shape dpa spacer. These coordination polymers are thermally stable up to 270–300 °C. They emit blue luminescence originating from ligand-centered emission.     

Syntheses,structures and luminescence of two cadmium entangled coordination polymers based on bis(imidazole) and biscarboxylate ligands

Two entangled coordination polymers [Cd₂(bib)(bdc)₂]_n (1) and [Cd₂(bib)(bda)₂]_n (2) were synthesized by the hydrothermal reaction (bib = 1,4-bis(2-methyl-imidazol-1-yl)butane, bdc = 1,2-benzenedicarboxylate, bda = 1,4-benzenediacetate). 1 exhibits an unusual 6-connected self-catenated 3D network based on Cd₂(COO)₂ dimer with the point symbol of (4⁴·6¹⁰·8). 2 exhibits a 3-fold interpenetrating 3D pcu network based on Cd₂(COO)₂ dimer. The different conformations of bib ligands (the anti–anti–anti conformation in 1 and gauche–anti–gauche conformation in 2) play the key role in the construction of different structures in 1 and 2. The luminescence and thermal stability were investigated.     

Three new d10 coordination polymers based on 2-(2-pyridyl)benzimidazole ligand: Synthesis,structures and properties

Three coordination polymers containing 2-(2-pyridyl)benzimidazole (PyHBIm) ligand, namely {[Zn₃(PyBIm)₃(PyHBIm)₂(tma)(H₂O)]?H₂O}_n (1), [Zn(PyHBIm)(oba)]_n (2), [Cd(PyHBIm)(oba)]_n (3), (tma = trimesate, oba = 4,4′-oxybis-(benzoate)), have been prepared through hydrothermal reaction. Compound 1 exhibits one-dimensional (1D) helical structure. However, compounds 2 and 3 display 1D meso-helical structure. These 1D structures are further assembled into three-dimensional (3D) networks through aromatic π–π stacking interactions and hydrogen bonding interactions. Moreover they all exhibit strong photoluminescence at room temperature and may be good candidates for potential luminescence materials.     

A novel porous coordination polymer based on rigid and flexible organic ligands

A novel bilayered coordination polymer with nanoporous channels [Ni₃(bix)₃(PTCO)₂ (H₂O)₄·6H₂O]_n (1) has been synthesized and the permanent porosity of (1) is confirmed by N₂ adsorption isotherm measurement.     

刚性与柔性连接的骨架型二芳烯聚合物

以二芳基乙烯(二芳烯)为共聚单体之一,通过便捷的合成步骤,合成了两个骨架型二芳烯类聚合物,研究了其溶解性、光致变色能力及抗疲劳性等性质。所得到的两个二芳烯聚合物均具有可逆的光致变色能力和优秀的抗疲劳性。在两个聚合物合成过程中,二芳烯与共聚单元的连接分别采用刚性和柔性两种连接方式,从而得到了具有不同分子量及光谱性质的二芳烯聚合物。     

Synthesis,structures, and luminescence of lanthanide coordination polymers constructed from benzimidazole-5,6-dicarboxylate and oxalate ligands

Three novel coordination polymers [(Eu₂(Hbidc)₂(ox)₂·(H₂O)₃] (1), [Tb₂(Hbidc)₂(ox)(H₂O)₂]·4H₂O (2), [Er₂(Hbidc)₂(ox)] (3) have been synthesized with hydrothermal reaction (H₃bidc = Benzimidazole-5,6-dicarboxylic acid, H₂ox = Oxalic acid) and characterized by elemental analysis, IR and X-ray single crystal diffraction. 1, 2 and 3 have the same crystal system of triclinic, but they exhibit different kinds of metal-organic framework structures. The luminescent properties of 1 and 2 were studied at room temperature.     

Syntheses,crystal structures of two coordination polymers constructed from imidazole-based dicarboxylate ligands containing alkyl group

Two new coordination polymers, |DMF|[Zn₂(C₇N₂O₄H₆)₂(C₁₀N₂H₈)] (1) and |(H₂O)₃|[Co(C₈N₂O₄H₉)₂(H₂O)₂] (2) have been synthesized based on 2-ethyl-1H-imidazole-4,5-dicarboxylic acid (H₃EtImDC) and 2-propyl-1H-imidazole-4,5-dicarboxylic acid (H₃PrImDC) as organic ligands, respectively. Single-crystal X-ray diffraction analysis reveals that compound 1 is a two dimensional layered structure constructed from two types of six-membered metallocycle, and the layers are stacked in an –ABCABC– sequence. For 2, the mononuclear [Co(C₈N₂O₄H₉)₂(H₂O)₂] molecules are connected with each other through hydrogen bonds forming a three dimensional supermolecular structure. Further characterizations including elemental analyses, IR spectra, and thermogravimetric analyses have been studied.     

Syntheses,structures and properties of novel d10 coordination polymers based on 4-[(1H-imidazol-4-yl)methylamino]benzoic acid ligand

Complete and partial deprotonation of new ligand 4-[(1H-imidazol-4-yl)methylamino]benzoic acid (H₂L) under hydrothermal conditions lead to the formation of two novel coordination polymers [ZnL]_n (1) and [Ag(HL)]_n (2). Complex 1 displays a rare three-dimensional (3,6)-connected rtl framework with (4 · 6²)₂(4² · 6¹⁰ · 8³) topology, while 2 has a one-dimensional chair-like structure including significant argentophilic Ag–Ag interactions. Both 1 and 2 show remarkable thermal stability and complex 1 was found to show strong blue luminescence with emission maxima at 381 nm upon excitation at 347 nm in the solid state at room temperature.     

Three transition metal cluster-based coordination polymers based on 1,4-naphthalenedicarboxylate and pyridine ligands

Three new cluster-based coordination polymers (CPs), namely, [Co₂(1,4-NDC)₂(py)₂(H₂O)] (1), [pyH]₄[Ni_6.5(1,4-NDC)₈(OH)(py)₄(H₂O)₃]∙H₂O (2) and Zn₄(1,4-NDC)₃(OH)₂(py)₂ (3) (1,4-NDCH₂ = 1,4-Naphthalenedicarboxylic acid, py = pyridine) have been hydrothermally synthesized and structurally characterized. Compound 1 is constructed from the tetranuclear clusters of [Co₄(COOR)₈(H₂O)₂]; while compound 2 contains trinuclear [Ni₃(COOR)₈(H₂O)₂]²⁻ or tetranuclear [Ni₄(COOR)₈(OH)₂]²⁻ units owning to the disorder of metal ions. Both compounds feature three-dimensional (3D) structures with the eight-connected bcu networks. Compound 3 is the first 1,4-NDCH₂-based 3D CP based on the rarely octanuclear [Zn₈(μ₃-OH)₄(COOR)₁₂] clusters with the six-connected pcu net. The three compounds are all constructed from the NDC²⁻ and py ligands but their structures are quite different, revealing the significance of metal ions in the structural modulation of CPs. In addition, the thermal stabilities of the three compounds were investigated.     

Syntheses,structures and luminescence of zinc and cadmium coordination polymers with bis(1,2,4-triazol-1-yl)butane and benzenedicarboxylate

The self-assembly reactions of the flexible ligand 1,4-bis(1,2,4-triazol-1-yl)butane (btb) and rigid ligand 1,4-benzenedicarboxylate (bdc) with Zn(II) or Cd(II) give two novel coordination polymers {[Zn(bdc)(btb)](H₂O)₅}_n (1) and {[Cd₂(bdc)₂(btb)(H₂O)₂](H₂O)₇}_n (2). Coordination polymer 1, a supramolecular isomer of [Zn₂(bdc)₂(btb)₂](H₂O)₂ [X.L. Wang, C. Qin, E.B. Wang, Z.M. Su, Chem. Eur. J. 12 (2006) 2680], is a special 2D (6,3) network, with six Zn(II) atoms at six corners and four bdc and two double btb at six edges. Coordination polymer 2 exhibits a distorted 3D cubic topology that is built from dimer Cd₂ units. The blue luminescent emission maxima at 420 and 439 nm for 1, 440 and 455 nm for 2 were observed in the solid state at room temperature.     

Assembly of two ferrous coordination polymers with triazole derivative: Syntheses,structures and magnetic properties

The reactions of Fe(II) salts with 1,4-bis(1,2,4-triazole-1-ylmethyl-benzene) (btx) give two new Fe(II) coordination polymers {[Fe(btx)₃](ClO₄)₂}_n (1) and {[Fe(btx)(SO₄)(H₂O)₂]}_n (2), which have been characterized by element analysis, PXRD, single-crystal X-ray diffraction and magnetic susceptibility. 1 shows infinite plait-like chain structure, while 2 exhibits as 2D grid. Magnetic studies indicate that the Fe(II) ions in the two coordination polymers retain in high-spin ground state upon cooling from 300 to 2 K, showing antiferromagnetic interactions.     

Syntheses and crystal structures of novel silver(I) coordination polymers based on linear or tetrahedral coordination environments

Two coordination polymers containing Ag(I) atoms, {[Ag(3-pia)](PF₆)}_n (1) and {[Ag(3-pia)₂](PF₆)}_n (2) (3-pia = N-pyridin-3-yl-isonicotinamide), have been synthesized using different solvents, and characterized by single X-ray analyses. In compound 1, Ag(I) atoms are linearly coordinated by two 3-pia ligands, resulting in one-dimensional chains. On the other hand, in compound 2, Ag(I) atoms are tetrahedrally coordinated by four 3-pia ligands, resulting in two-dimensional sheets.     

Two transition metal coordination polymers constructed from 1,4-naphthalenedicarboxylate and N/O-donor auxiliary ligands: Syntheses,structures and magnetic property

Two transition metal coordination polymers (CPs), namely, Cd(1,4-NDC)(py) (1), Co₂(1,4-NDC)₂(DMF)₂ (2) (1,4-NDCH₂ = 1,4-naphthalenedicarboxylic acid, py = pyridine, DMF = N,N-dimethylformamide) have been synthesized and characterized. Compound 1 contains one-dimensional chains, which are further linked by the NDC^2 − ligands to form a three-dimensional framework with a 5,5T2 topology network. There exist two types of left-hand helical chains interconnected to each other through the Cd(II) center in compound 1. Although compound 2 has been reported previously, in this work the synthetic method of 2 is modified to obtain high quality crystals. In addition, the magnetic property of compound 2 is investigated, which shows the metamagnetic behavior induced by the external field.     

Bisphosphino ureas: flexible ligands with rigid backbone

The nickel(0) complex [Ni{η²-(PPh₂NMe)₂CO}{η¹-(PPh₂NMe)₂CO}] 1 was obtained by the reaction of NiCl₂·6H₂O with two equivalents of the ligand (PPh₂NMe)₂CO in the presence of zinc as reducing agent. The structure of 1 was unambiguously determined by ¹H and ³¹P–{¹H} NMR spectroscopy and compared to the known structures of the extremely strained Pd(II) and Mo(0) complexes of (PPh₂NMe)₂CO.     

3D Ln–Ag (Ln = Nd; Eu) coordination polymers based on N- and O-donor ligands: Synthesis, crystal structures and luminescence

The self-assembly of isonicotinic acid with metal salts under hydrothermal conditions gave two isostructural 3D 4d–4f coordination polymers, Ln₂Ag₄(OX)(IN)₆(H₂O)_1.5 · 2(ClO₄) [Ln = Nd (1); Eu (2), OX = oxalic acid, IN = isonicotinic acid]. Compounds 1 and 2 are 3D coordination frameworks via 2D layers built by carboxylate groups of isonicotinic acid and oxalate ligands coordinating to metal centers and completing the linear linker by silver ions. Furthermore, the luminescent properties of complex 2 have also been investigated.     

Two novel 3D self-threading coordination polymers with CdSO4 topology: Syntheses,structures and properties

Two new isostructural metal-organic frameworks, namely [Co(HL)(bpp)] · 0.5H₂O (1) and [Zn(HL)(bpp)] · 3H₂O (2) (H₃L = 5-(2′-carboxy-biphenyl-4-ylmethoxy)-isophthalic acid, bpp = 1,3-bis(4-pyridyl)propane), have been hydrothermally synthesized and further characterized by single crystal X-ray diffraction, powder X-ray diffraction, elemental analyses, IR spectra and TG analyses. Compounds 1 and 2 exhibit interesting 3D frameworks of (6⁵.8)-CdSO₄ topology with dangling arm (i.e. the uncoordinated 2′-carboxy-biphenyl-4-ylmethoxy group of HL ligand). The remarkable feature of these two compounds is that each dangling arm threads into two 6-membered rings belonging to the 3D net itself, displaying the self-threading character. The magnetic properties of 1 and photoluminescence of 2 have also been investigated.     

Divalent cobalt,zinc, and copper coordination polymers based on a new bifunctional ligand: Syntheses,crystal structures,and properties

Three new coordination polymers, namely, [ML(H₂O)]_n (M = Co (1), Zn (2)) and [CuL(DMF)]_n (3), have been hydrothermally synthesized through the reaction of bifunctional ligand 5-((2-methyl-1H-imidazol-1-yl)methyl)benzene-1,3-dioic acid (H₂L) with divalent cobalt, zinc and copper salts, and structurally characterized by elemental analysis, IR and X-ray diffraction. Both complexes 1 and 2 are two-fold interpenetration 3D frameworks. Complex 3 exhibits (3,6)-connected framework with (4.6²)₂(4².6¹⁰.8³) topology. Furthermore, UV–vis absorption spectra and powder X-ray diffraction (PXRD) were investigated as well.     

Two novel Cd(II)-based coordination polymers constructed from isomeric double betaine ligands: Syntheses,structures and fluorescent properties

Two novel Cd^2 + based coordination compounds based on two isomeric double betaine ligands (1,4-Bis(4-carboxylatopyridinium-1-methylene)benzene (H₂L₁Cl₂) and 1,4-Bis(3-carboxylatopyridinium-1-methylene)benzene (H₂L₂Cl₂)) were synthesized, structurally and optically characterized. Both compounds show two dimensional sheet architectures with different features depending on structural motifs that ranging from helical chain to linear chain, and the spatial arrangements of coordinated ligands as well as their unlike coordination modes. They further exhibit the way how three dimensional supramolecular isomers form via weak interactions. Meanwhile, two compounds exhibit intense fluorescence attributing to the ligands' emissions with stokes shift.     

Two new d10 2D layered frameworks based on 1,2,4-triazole bridge: Syntheses,structures, and fluorescence

Two new triazole-bridging d¹⁰ 2D layered frameworks, [Cd(H₂O)₂(Httr)₂](SiF₆) (1), [Zn(ttr)(OAc)] (2) (Httr = 3-amino-1H-1,2,4-triazole), were synthesized with structures and fluorescence characterized. 1 is based on a kind of 16-membered ring with μ₂-1 κN:4 κN coordination mode of Httr and 2 is constructed from the fuse of different 6- and 16-membered rings with μ₃-1 κN:2 κN:4 κN mode of ttr⁻. The hydrogen bondings in 1 and 2 between the anions and ttr connect the 2D layers into 3D supramolecular architectures. The fluorescent studies of compounds 1 and 2 show an important difference, emission at 460 nm in 1 and a dual one at 334 and 462 nm in 2.