3D pillar-layered coordination polymers based on 4d–4f heterometallic assembly

By control of mixed ligands with particular coordination sites, heterometallic coordination polymers, [Ln₂(H₂O)₂Ag(C₂O₄)₂(ina)₃]_n (Ln = Eu (1), Dy (2), Hina = isonicotinic acid) and {[LnAg(C₂O₄)(na)₂]·2H₂O}_n (Ln = La (3), Tb (4), Hna = nicotinic acid), have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, thermogravimetric analysis (TGA), and single-crystal X-ray diffraction. These coordination polymers feature 3D pillar-layered coordination frameworks constructed from two-dimensional (2D) lanthanide–carboxylate layers and Ag(ina) or Ag(na) pillars. It is interesting that the in situ decarboxylation of pyridine-2,3-dicarboxylic acid into nicotinic acid was observed. The luminescent properties of 1 and 4 were also studied.     

Syntheses and structures of 3d–4d heterometallic coordination polymers based on 4-amino-1,2,4-triazole

Three heterometallic coordination polymers based on 4-amino-1,2,4-triazole (atrz), Cd_2.98Fe_2.02(atrz)₆(SCN)₁₀·2H₂O (1), Cd_2.86Co_2.14(atrz)₆(SCN)₁₀·2H₂O (2), and Cd_2.02Ni_2.98(atrz)₆(SCN)₁₀·2H₂O (3), were synthesized. Crystal structures of the polymers were determined by single-crystal X-ray diffraction, X-ray powder diffraction, and infrared analysis. The complexes exhibit a 3-D structure and are isostructural, but entail different durations for transformation from a 1-D polymer to a 3-D structure. The results of vibrating sample magnetometry for 1 indicate that the complex exhibits weak paramagnetism.     

Three interpenetrated copper(Ⅱ) coordination polymers based on a V-shaped ligand:Synthesis,structures,sorption and magnetic properties

Three new CuⅡ coordination polymers,[Cu2(oba)2(H2O)(DMF)].3H2O(1),[Cu4(oba)4(DMF)4].4H2O.DMF(2) and [Cu2(oba)(hmp)2](3)(H2oba = 4,4'-oxybis(benzoic acid),Hhmp = 2-pyridine methanol,DMF = N,N'-dimethylformamide) were synthesized by solvothermal reactions and characterized by single-crystal X-ray diffraction.Both complexes 1 and 2 take three-dimensional(3D) three-fold interpenetrating PtS topology with 1D channels.In complex 3,Cu4 clusters were formed by the chelating hmp ligands,and then the clusters were fu...     

Synthesis and X-ray crystal structures of a series of 3d–4f lanthanide complexes: lanthanide(III)–copper(II) coordination polymers with 2,5-pyridinedicarboxylic acid ligand

A series of lanthanide–transition metal (Ln–M) complexes, namely, {[Ln₂Cu(pydc)₄(H₂O)₃]·H₂O} _n (Ln = Tb, Eu, Sm or Gd) (H₂pydc = 2,5-pyridinedicarboxylic acid) have been synthesized hydrothermally by self-assembly of the lanthanide ions, copper(II) ions and 2,5-pyridinedicarboxylic acid. All the complexes were characterized by physicochemical and spectroscopic methods; in addition, structural analyses revealed that all four complexes crystallized in monoclinic space group P2₁ /c. The molecular structure contains both Cu and Ln atoms, with pydc ligands bridging the four coordinate Cu(II) centers and eight coordinate lanthanide centers to form a 3-D net structure. Hence, copper is oxidized from Cu(I) to Cu(II) during the preparation. In addition, the thermogravimetric analysis of 1 is discussed. Contrary to expectations, compounds 1–3 show no photoluminescent properties. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Heterometallic 3d–4f coordination polymers: Synthesis,characterization and magnetic properties of 1D zigzag chains containing samarium and terbium

Reaction of the copper precursor [Cu(MeOsaltn)(H₂O)] (H₂MeOsaltn = N,N′-bis(3-methoxysalicylidene)-1,3-diaminopropane) with Ln(NO₃)₃·6H₂O (Ln = Sm and Tb) and pyrazine-2,3-dicarboxylic acid (H₂pyrdic) results in the formation of 1D zigzag chains with the general formula of [Cu(MeOsaltn)Ln(NO₃)(pyrdic)]_n·nDMF. X-ray crystal structures reveal that the samarium and terbium compounds are isostructural and crystalize in the orthorhombic space group Pbcn. The chains are composed of heterodinuclear copper–lanthanide building blocks which are linked by the pyrazine-2,3-dicarboxylate bridging units. Temperature-dependent susceptibility measurements indicate antiferromagnetic exchange interactions for the samarium–copper chain whereas for the terbium–copper compound ferromagnetic interactions are observed.     

Synthesis,crystal structures and properties of 3d–4f heterometallic coordination polymers,using [Fe(bipy)(CN)4]2− as a versatile building block

Two novel cyano-bridged lanthanide-transition-metal complexes, K[Fe(bipy)(CN)_{4 2}Tb(H₂O)₄]·3H₂O (1) and [Fe(bipy)(CN)₄Sm(phen)(NO₂)(H₂O)₂]·H₂O (2) (bipy = 2.2-bipyridine; phen = 1, 10-phenanthroline), have been prepared and structurally characterized. Complex (1) possesses a cyano-bridged two-dimensional (2D) honeycomb-like structure with centrosymmetric [Fe^II(bipy)(CN)_{4 2}Tb^III(H₂O)₄]^– anions, potassium cations, and water of crystallization molecules. Complex (2) consists of a cyano-bridged one-dimensional (1D) ladder structure with neutral [Fe^II(bipy)(CN)₄Sm^III(phen)(NO₂)(H₂O)₂] and water of crystallization molecules. The magnetic properties of (1) have been investigated in the 2.0–300 K range. The data for (1) reveal that magnetic interactions between Tb³⁺ ions through the low-spin Fe²⁺ ions are negligible.     

Three-dimensional 3d–4f hetero-bimetallic coordination polymers through hydrogen bonds: synthesis,structures and mössbauer spectrum analysis

Four cyano-bridged 3d–4f hetero-bimetallic Ln(III)–Fe(III) assemblies, {[Ln(DMF)₄(H₂O)₃(µ-CN)Fe(CN)₅]· H₂O} _n (Ln?=?Ce (1), Nd (2), Sm (3) and Gd (4); DMF?=?N,N-dimethylformamide), have been synthesized. X-ray crystallographic analysis of both 3 and 4 reveals three-dimensional network structures resulting from hydrogen bonds in the crystals. With respect to the coordination number on Sm(III) atoms, 3 is different from previously reported structures. Structural comparison indicates that the differences in magnetic properties between 3 and 4 do not derive from structural factors. Mössbauer spectra at both 298 and 10?K reveal that the characteristic quadrupole splitting for low-spin Fe(III) ions (S?=?1/2) remains unchanged, indicating that the spin state of Fe(III) ions in 1–4 is not affected by temperature. The magnetic anisotropy derived from the ground states of Ln(III) ions with odd 4f ⁿ electrons (n?=?1, 3, 5 and 7), ²F_5/2,⁴I_9/2, ⁶H_5/2 and ⁸S_7/2 for Ce(III), Nd(III), Sm(III) and Gd(III), respectively, dominates the exchange interaction in the Ln(III)–NC–Fe(III) systems.     

Syntheses,crystal structures,and photoluminescent properties of two new Cd(II) coordination polymers based on biphenyl-2,2′,4,4′-tetracarboxylate and dipyridyl-containing ligands

Two new Cd(II) coordination polymers, [Cd₂(btc)(dpe)_1.5(H₂O)]_n (1) and [Cd₂(btc)(bpp)(H₂O)]_n (2), were prepared by the hydrothermal reaction of cadmium nitrate with H₄btc (H₄btc = biphenyl-2,2′,4,4′-tetracarboxylic acid) in the presence of 1,2-di(4-pyridyl)ethylene (dpe) and = 1,2-bis(4-pyridyl)propane (bpp), respectively, structurally characterized by single-crystal X-ray diffraction, and further characterized by elemental analysis, IR spectroscopy, and thermogravimetric analysis. In 1, btc^4? connect six Cd²⁺ ions, forming a 3-D (3,3,6)-connected [Cd₂(btc)] net, and further connected by 1-D [Cd(dpe)]_n chains to construct the final (4,5,6)-connected (4².5².6⁵.7)(4³.6².7)(4⁵.5³.6⁴.7².8) net. In 2, a 3-D [Cd₂(btc)] net is also constructed from btc^4? connecting six Cd²⁺ ions, giving a 3-D (3,4,7)-connected network. The overall structure of 2 can be regarded as a (4,4,6)-connected (4⁵.6⁴) (4².5.6².8) (4³.5⁴.6⁷.7) framework with bpp linking adjacent Cd ions. Structural comparisons show that the secondary auxiliary N-donors have important effects on the final structure and properties. Photoluminescent properties of 1 and 2 are also discussed.     

A series of three-dimensional 3d–4f heterometallic coordination frameworks based on pyridinedicarboxylic acid

Four new 3d–4f heterometallic coordination polymers [Cu₃Eu₂(2,5-pydc)₆(H₂O)₁₂]·4(H₂O) (1), [Zn₂Eu₂(2,5-pydc)₅(H₂O)₂]·3(H₂O) (2), and [Co₃Ln₂(2,6-pydc)₆(H₂O)₆]·4(H₂O) (Ln = Eu, 3; Dy, 4) (H₂pydc = pyridinedicarboxylic acid) have been synthesized and characterized. All of these compounds have extended 3D coordination frameworks containing supramolecular 1D channels, in which lattice water molecules are located. Hydrogen bonds stabilize the 3D frameworks. Additionally, a study of their fluorescence properties has indicated that compounds 1 and 2 show the characteristic transitions of Eu³⁺. Weak antiferromagnetic interactions are observed in compound 3.     

Synthesis,structures and luminescent properties of 4d–4f heterometallic coordination frameworks based on lanthanide oxalate substructures with nicotinate bridging ligands

Four transition–lanthanide metal–organic coordination polymers, namely [Ag₂Ln(nic)₄(H₂O)₄ · (ClO₄) · H₂O] [Ln = Eu (1), Gd (2)] and [AgLn(nic)₂(ox)_0.5(H₂O)₂ · (ClO₄) · H₂O] [Ln = Tb (3), Yb (4)] (nic = nicotinate; ox = oxalate) have been synthesized by the hydrothermal reactions of 4d and 4f metal salts with N-/O-donor ligands. The isostructural complexes 1 and 2 exhibit novel 2D wave-like heterometallic layers constructed by the assembly of 1D chains of lanthanide–carboxylate with Ag(nic)₂ subunits. Complexes 3 and 4 show another unusual 3D heterometallic coordination framework constructed from 2D lanthanide–oxalate layers and pillar-like Ag(nic)₂ subunits. Furthermore, the luminescent properties of complexes 1 and 3 were studied.     

Hydrothermal synthesis,characterization and properties of a d10 metal coordination polymer with a layered structure based on carboxyphosphinate ligand, 4,4′-bipyridine and four-coordinated zinc ion

Abstract

Hydrothermal reaction of Zn(NO₃)₂ · 6?H₂O with 2-carboxyethyl(phenyl)phosphinate (H₂L) and 4,4'-bipyridine (4,4′-bipy) led to a novel zinc(II) carboxyphosphinate [ZnL(4,4′-bipy)_0.5]_n (1). The zinc ion is tetrahedrally coordinated by two phosphinate oxygen atoms, one carboxylate oxygen atom, and one nitrogen atom of 4,4′-bipy ligand. The L^2- ligand and zinc ion can be seen as three- and four-connected nodes, respectively. Compound 1 shows a layered network with (3,4)-connected topology. It exhibits a broad blue fluorescent emission band at 459?nm, which can be attributed to 4,4′-bipy intraligand emission as well as to H₂L emission. It is a diamagnetic system between 300?K and 11?K.     

Two novel interpenetrated zinc(Ⅱ) and cadmium(Ⅱ) coordination polymers based on 4-imidazole-benzoate:Syntheses,crystal structures and properties

Two novel interpenetrated coordination polymers,[Zn(IBA)2]n (1) and {[Cd(IBA)2(H2O)].4H2O}n (2),have been synthesized by using 4-imidazole-benzoic acid (HIBA) as ligand under hydrothermal conditions. Complex 1 crystallizes in a chiral space group and has a two-fold interpenetrated 2D network structure with (4,4) topology,while complex 2 is a 3D porous dia network with four nets interpene-trating each other. The SHG activity of 1 and the photoluminescent property of 2 have been investigated.     

Syntheses,crystal structures,and optical properties of a series of transition metal coordination polymers with chelidamic acid and 4,4′-bipyridine

A series of transition metal (Zn, Cu, Mn) complexes with chelidamic acid (2,6-dicarboxy-4-hydroxypyridine, H₃CAM) and 4,4′-bipyridine (bipy), [Zn₂(bipy)Cl₂] _n (1), {[Zn₂(HCAM)(H₂CAM)₂]?·?(bipy)?·?3.5H₂O} _n (2), [Mn₃(HCAM)₃(H₂O)₇]?·?(bipy)?·?3H₂O (3), [Mn₂(HCAM)₂(bipy)?·?(H₂O)₂]?·?4H₂O (4), [Cu₂(HCAM)₂(bipy)?·?(H₂O)₂]?·?4H₂O (5), and Cu₂(HCAM)₂(bipy)?·?(H₂O)₂ (6), have been synthesized by hydrothermal or solution methods and characterized by single-crystal X-ray diffraction. The structural analyses reveal that 1 exhibits a zigzag chain of Zn(II), Cl^?, and 4,4′-bipyridine. In 2, a 1-D polymeric [Zn₂(HCAM)(H₂CAM)₂] _n chain and a discrete 4,4′-bipyridine assemble into a 2-D supramolecular network via H-bonds. Complex 3 consists of asymmetric units of Mn₃(HCAM)₃(H₂O)₇ that are linked by hydrogen bonds to form a 2-D H-bonded network. Complexes 4–6 are isomorphous and possess discrete structures. The photoluminescent properties of 1–6 at room temperature were studied.     

3D Heterometallic (3d–4f) coordination polymers: A ferromagnetic interaction in a Gd(III)–Cu(II) couple

Four 3d–4f heterometallic coordination polymers, [Cu₃(IDA)₆Ln₂] · n(H₂O) [IDA =  iminodiacetate dianion; Ln = Gd, n = 3 (1); Ln = Nd, n = 6 (2); Ln = Sm, n = 6 (3)] and [Cu(Cl)(NTA)Sm(H₂O)₆] · (ClO₄) · (H₂O) (4) [NTA = nitrilotriacetate trianion], have heen synthesized and characterized by single crystal X-ray diffraction analysis. Complexes 1–3 are isomorphous, showing a 3D coordination framework having tubular channels filled by lattice water molecules running parallel to the c axis. Whereas complex 4 is a 1D polymer of alternating copper and samarium ions connected by NTA, and the chains get involved in H-bonding interactions resulting in a 3D network. A low temperature magnetic study reveals ferromagnetic interactions for complex 1. Thermogravimetric and X-ray powder diffraction analyses of 1, 2 and 3 show that the covalently bonded 3D network remains almost unaffected after deaquation.     

Syntheses, crystal structures, and magnetic properties of four one-dimensional metal–nitroxide coordination polymers linked by flexible dicarboxylate anions

Four new one-dimensional coordination polymers [Co(IM4Py)₂(adi)(H₂O)₂] _n , [Zn(IM4Py)₂(adi)(H₂O)₂] _n , [Cd(IM4Py)₂(adi)(H₂O)₂] _n , and [Ni(IM4Py)₂(glu)(H₂O)₂] _n (IM4Py = 2-(4′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl, adi = adipate anion and glu = glutarate anion) were synthesized and structurally characterized. The single-crystal X-ray analyses indicate that all four complexes crystallize in neutral one-dimensional chains in which the nitroxide–metal–nitroxide units are bridged by the flexible dicarboxylate anions. The adipate anions adopt the anti/gauche/anti and anti/anti/anti conformations in the Co(II), Zn(II), and Cd(II) complexes, while the glutarate anions only possess the anti/anti conformation in the Ni(II) complex. The magnetic properties of the Co(II) and Ni(II) complexes show the occurrence of weak antiferromagnetic interactions between the metal atoms and the nitroxide radicals.     

Synthesis,structures and magnetic properties of two 2D → 3D entangled Cobalt(II) coordination polymers

Two Co(II) coordination polymers, namely Co(HBTC)(4-bpdb)·H₂O (1) and Co(HBTC)(3-bpdb)·H₂O (2) (H₃BTC = 1,3,5-benzenetricarboxylic acid, 4-bpdb = 1,4-bis-(4-pyridyl)-2,3-diaza-1,3-butadiene, 3-bpdb = 1,4-bis(3-pyridyl)-2,3-diaza-1,3- butadiene), have been hydrothermally synthesized and characterized both structurally and magnetically. Compound 1 exhibits a (2D → 3D) polythreaded architecture. It is assembled from HBTC^2? ligands to form a 2D puckered (4,4) layer plus 4-bpdb ligands which are orientated above and below each layer. The structure of compound 2 consists of a 2D (3,5) wavelike sheet constructed from HBTC^2? anions and 3-bpdb spacers. The uncoordinated carboxyl groups of the HBTC^2? ligands protrude from both sides of the wavelike sheet to form a 2D → 3D interdigitated motif. The magnetic properties of both compounds are also investigated, indicating antiferromagnetic interactions between the adjacent metal centers.     

Two isomorphous Mn(II) and Co(II) 5-amino-tetrazolate coordination polymers with magnetic Δ-chains: crystal structures and magnetic properties

Two Co(II) and Mn(II) coordination polymers, which have been synthesized under hydrothermal conditions, are isomorphous with magnetic Δ-chains containing trinuclear triangular [M(3)(μ(3)-OH)] clusters. The Δ-chains are bridged by isonicotinic spacers to generate a two-dimensional scalariform layer structure. Magnetic investigations indicate that Co(II) compound exhibits not only spin canting but also metamagnetic behaviors, while only spin-canted antiferromagnetic behaviors was observed in Mn(II) compound.     

Syntheses,crystal structures,and luminescent properties of three metal coordination polymers based on adipic acid and 2-(pyridine-3-yl)-(1H)-benzimidazole

Three new metal coordination polymers constructed from adipic acid and 2-(pyridin-3-yl)-(1H)-benzimidazole ligands, [M(ADP)(3PBI)₂(H₂O)₂]·2H₂O (M = Ni and Co for 1 and 2, respectively) and [Cd(ADP)(3PBI)(H₂O)] (3) [ADP = adipic acid dianion; 3PBI = 2-(pyridin-3-yl)-(1H)-benzimidazole], have been synthesized by hydrothermal reactions and were characterized by X-ray single-crystal diffraction, elemental analyses, IR, powder X-ray diffraction, and thermogravimetry. Complexes 1 and 2 are isostructural. Both form a 1-D linear chain structure, which is further assembled into a 3-D supramolecular framework by π?π stacking and hydrogen bonding interactions. Complex 3 possesses a binuclear unit and displays a 2-D layer which is further extended to a 3-D supramolecular architecture via hydrogen bonding and other weak packing interactions. The luminescent properties of 3 were investigated in the solid state at room temperature.     

Flexible bis(pyridyl-tetrazole) ligand-induced ring-containing metal–organic coordination polymers: synthesis,structures, and properties

Three coordination polymers (CPs), [Co(3-bptzp)(BDC)] (1), [Zn(3-bptzp)(BDC)] (2), and [Cd(3-bptzp)(BDC)] (3) (3-bptzp = 1,4-bis(5-(3-pyridyl)tetrazolyl)propane, H₂BDC = 1,3-benzenedicarboxylic acid), were synthesized under hydrothermal conditions. The CPs were structurally characterized by single-crystal X-ray diffraction, infrared spectroscopy (IR), elemental analyses, and powder X-ray diffraction (PXRD). Complexes 1–3 represent the first examples of CPs based on the flexible bis(pyridyl-tetrazole) 3-bptzp. Structure analyses reveal that 1–3 are 1-D ring-containing polymeric chains. For 2 and 3, adjacent 1-D chains are extended to 2-D supramolecular networks by hydrogen bonding. Dye adsorption properties of 1–3, electrochemical properties of 1, and fluorescent-sensing behaviors of 2 and 3 have also been investigated.     

pH-Controlled assembly of two POM-based inorganic–organic hybrid copper coordination polymers: synthesis,structures and properties

Transition Metal Chemistry - Two POM-based copper coordination polymers constituted by Keggin-type polyoxometalates (POMs), [Cu2 (SiW12O40)2 (Fbtx)3 (H2O)4]n (1) and {[Cu2 (SiW12O40) (Fbtx)2...