Hydrothermal syntheses and characterization of four 2-D lanthanide coordination polymers with glutarate and 1,10-phenanthroline

Four 2-D coordination polymers Ln₂(phen)₂(C₅H₆O₄)₃ [Ln?=?Pr(1), Eu(2), Er(3), Yb(4), phen?=?1,10-phenanthroline] were obtained via hydrothermal reactions and determined by X-ray diffraction analysis. The crystal structure data reveal that these complexes are isostructural. In the asymmetric unit, the two Ln(III) ions are nine-coordinate and have similar coordination environments. The Ln(III) ions are built into 2-D layers by three different coordination modes of glutarate. The resulting 2-D layer forms 3-D supramolecular architecture by two types of π···π stacking interactions. All the complexes were characterized by IR spectra and thermogravimetric analysis, and the emission spectrum shows that Eu₂(phen)₂(C₅H₆O₄)₃ possesses strong luminescence.     

Two- and three-dimensional coordination polymers of lanthanide tartrate: synthesis,crystal structures and luminescence

Several new coordination polymers of lanthanide tartrate with three types of topological structures, namely [Ln₂(DL-tart)₃(H₂O)₃] · 1.5H₂O [Ln = La (1), Nd (2), and Sm (3)], [Ln₂(D-tart)₃(H₂O)₂] · 3H₂O [Ln = Eu (4), Tb (5), and Dy (6)], and [Lu(C₄H₄O₆)(C₄H₅O₆)] · 2.5H₂O (7), have been synthesized by hydrothermal synthesis. X-ray crystallographic analysis reveals that 1 is a unique 3-D network, whereas 5 with a 3-D network and 7 with a 2-D network are isomorphous with their analogs. All lanthanide ions are nine-coordinate through oxygen donors. Four different coordination modes of tartrate occur in these complexes. Luminescence spectra reveal that 4, 5, and 6 emit characteristic luminescence of corresponding lanthanide ions.     

Mononuclear and binuclear lanthanide(III) complexes: syntheses,structural, photophysical and thermal properties

Six new Ln(III) complexes viz., [Gd(tptz)(SCN)₃(CH₃OH)₂OH₂]·CH₃OH (1), [Eu(tptz)(SCN)₃(CH₃OH)₂OH₂]·CH₃OH (2), [Tb(tptz)(SCN)₃(OH₂)₃]₄ (3), [Gd(tptz)(OBz)₂(μ-OBz)OH₂]₂·2H₂O (4), [OH₂(OBz)₂(tptz)Eu₁(μ-OBz)₂Eu₂(tptz)(OBz)₂OH₂]·CH₃OH·7H₂O (5), and {[Tb₁(tptz)(OBz)₂(μ-OBz)]₂·[Tb₂(tptz)(OBz)₃CH₃OH]₂}·2CH₃OH·4H₂O (6) (Ln = Gd, Eu, Tb; tptz = 2,4,6-tris(2-pyridyl)-1,3,5-triazine; BzONa = sodium benzoate), have been synthesized and characterized by physicochemical methods including single-crystal X-ray crystallography. The X-ray studies demonstrate that 1–3 are mononuclear, whereas 4–6 are binuclear. The photophysical properties of 1–6 have been studied with ultraviolet absorption and emission spectral studies. Their thermal properties have been studied by thermogravimetric (TG) and derivative thermogravimetric analysis (DTG), demonstrating that the final product after decomposition was Ln₂O₃ for all these complexes.     

Hydrothermal syntheses,crystal structures and luminescence properties of two lanthanide dinuclear complexes with hexafluoroglutarate

Two complexes [Ln₂(hfga)₂(phen)₄(H₂O)₆] · hfga · 2H₂O (H₂hfga = hexafluoroglutaric acid, phen = 1, 10-phenanthroline, Ln=Tb, 1; Eu, 2) were synthesized under hydrothermal conditions and their structures determined by X-ray crystallography. The complexes consist of dinuclear units with an inversion center. Each Ln(III) is nine-coordinate with two carboxylate oxygens from two hfga ligands, three oxygens from water and four nitrogens from two phen molecules. Two carboxylate groups of one hfga adopt monodentate coordination to Ln(III) as a long bidentate bridge linking two Ln(III) ions to form a dimer. Ln(III) ··· Ln(III) distances of 9.027(3) Å for 1 and 9.043(3) Å for 2 were observed. Both complexes emit strong fluorescence and show characteristic emission of Tb(III) and Eu(III) ions, respectively.     

Synthesis,crystal structures,and infrared spectroscopy of a series of lanthanide phosphonoacetate coordination polymers

Hydrothermal reactions of lanthanide chloride, phosphonoacetic acid (H₂O₃PCH₂COOH), and water in the presence of HCl provide a series of lanthanide coordination polymers. FT-IR spectra confirm that there are three kinds of structures among seven complexes, {[Ln₂(O₃PCH₂CO₂)₂(H₂O)₃]?·?H₂O}_∞ (type I) (Ln?=?La^III for 1; Pr^III for 2; Nd^III for 3 and Eu^III for 4), [Ln(O₃PCH₂CO₂)(H₂O)₂]_∞ (type II) (Ln?=?Tb^III for 5), and [Ln(O₃PCH₂CO₂)(H₂O)₂]_∞ (type III) (Ln?=?Ho^III for 6 and Yb^III for 7). Complexes 1–5 show 2-D 4,4,5,5-connected (4⁴?·?6²)(4⁵?·?6)(4⁶?·?6⁴)(4⁸?·?6²) topology networks and 2-D 4-connected (4⁴?·?6²) topology networks and then are further linked into 3-D supramolecular networks by hydrogen-bonding interactions; 6 and 7 both exhibit a 3-D 4-connected (4²?·?6³?·?8) topology with 1-D dumbbell-shaped channels. The results indicate infrared spectroscopy is in accord with the result of single-crystal X-ray analysis.     

Syntheses,crystal structures,and photophysical properties of two 2-D coordination polymers

Two coordination polymers, [Mn(dipt)(m-BDC)₃] _n (1) and [Pb(mip)(1,4-NDC)] _n (2) [dipt?=?2-(2,4-dichlorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline, mip?=?2-(3-methoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline, m-BDC?=?isophthalic acid, 1,4-NDC?=?naphthalene-1,4-dicarboxylic acid], have been synthesized by hydrothermal reactions and characterized by elemental analysis, thermogravimetric analysis, infrared spectrum, and single-crystal X-ray diffraction. Single-crystal X-ray diffraction reveals that 1 and 2 have 1-D chain architecture. Complex 1 has a 2-D-layered structure constructed from C–H···O hydrogen bonds. Complex 2 has a 2-D-layered structure constructed from N–H···O hydrogen bonds and π–π interactions. TG analyses suggest 1 and 2 have excellent thermal stabilities from hydrogen bonds and π–π interactions. Mn(II) in 1 has trigonal bipyramidal geometry surrounded by three carboxylate oxygen atoms from three monodentate bridging m-BDC and two nitrogen atoms from one dipt. Pb(II) has [:PbN2O4] pentagonal bipyramidal geometry in 2. The luminescent properties for dipt, mip, 1, and 2 are also presented.     

Four Zn(II)/Cd(II) coordination polymers derived from isomeric benzenedicarboxylates and 1,6-bis(triazol)hexane ligand: synthesis,crystal structure,and luminescent properties

Four coordination polymers, [Zn(o-bdc)(bth)_0.5(H₂O)] _n (1), [Cd(o-bdc)(bth)_0.5(H₂O)] _n (2), [Zn(m-bdc)(bth)] _n (3), and [Cd(p-bdc)(bth)?·?(H₂O)₂] _n (4) (where o-bdc?=?1,2-benzenedicarboxylate, m-bdc?=?1,3-benzenedicarboxylate, p-bdc?=?1,4-benzenedicarboxylate, and bth?=?1,6-bis(triazol)hexane), have been hydrothermally synthesized and structurally characterized. Both 1 and 2 are isostructural, featuring two binodal architectures: (6³)(6⁵·8) topology in terms of o-bdc and Zn^II/Cd^II as three- and four-connected nodes. Complex 3 shows a 2-D (4,4) network with the Zn?···?Zn?···?Zn angle of 57.84°, whereas 4 exhibits planar 2-D (4,4) network. These 2-D networks of 3 and 4 are extended by supramolecular interactions, such as CH?···?π/π–π stacking and hydrogen-bonding into 3-D architecture. A structural comparison of these complexes demonstrates that the dicarboxylate building blocks with different dispositions of the carboxyl site play a key role in governing the coordination motifs as well as 3-D supramolecular lattices. Solid-state properties such as photoluminescence and thermal stabilities of 1–4 have also been studied.     

Multiple modulator-induced syntheses,crystal structures,and luminescent properties on hippuric acid and bovine serum albumin of Ln(III) complexes with 2,2′-oxybis(benzoic acid)

Six new coordination complexes, Ln₂(2,2′-oba)₂(phen)₂(ox)(H₂O)₂ (Ln = Eu 1, Tb 2), Ln₄(2,2′-oba)₆(phen)₂ (Ln = Eu 3, Tb 4), Eu₄(2,2′-oba)₆(phen)₂(H₂O) (5), and K[Eu(2,2′-oba)₂(phen)₂] (6) [2,2′-H₂oba = 2,2′-oxybis(benzoic acid), phen = 1,10-phenanthroline, H₂ox = oxalic acid] were synthesized by hydrothermal reactions with the same compound molar ratios but different modulatory reagents (MRs). Complexes 1–5 have different 1-D chain structures and 6 shows a mononuclear structure. These complexes form diverse 3-D supramolecular networks through hydrogen bonds. The interaction between these complexes and hippuric acid (HA) or bovine serum albumin (BSA) was investigated by fluorescence spectral analysis. Interestingly, the hippuric acid could quench the luminescence of these complexes while the fluorescence of BSA could be quenched by these complexes. Results suggested that the complexes may be potential luminescent testing reagents for HA or BSA by significant fluorescence quenching of Ln³⁺ or BSA, respectively, through a static and dynamic quenching process.     

Hydrothermal synthesis and crystal structure of two new lanthanide coordination polymers with 1,2-phenylenediacetate

Two new compounds {[Ln₂(1,2-pda)₃(H₂O)₂]·?2H₂O} _n (1,2-H₂pda?=?1,2-phenylenediacetic acid, Ln?=?Tb, 1; Ho, 2) were prepared by hydrothermal reaction and characterized by X-ray crystallography. The Ln³⁺ is nine-coordinate by eight oxygen atoms of six 1,2-pda ligands and one oxygen of water. Ln³⁺ ions are bridged by 1,2-pda ligands via bridging/chelating-bridging pentadentate and chelating-bridging/chelating-bridging hexadentate coordination to form 3-D framework structures. Complex 1 emits strong green fluorescence corresponding to ⁵D₄???⁷F_j (j?=?6–3) transitions of the Tb³⁺.     

Synthesis,Characterization and Properties of TbIII and DyIII Coordination Compounds based on Isomeric Ligands

Reactions of the isomeric ligands Hpztza [Hpztza = 5‐(2‐pyrazinyl)tetrazole‐2‐acetic acid] and Hpmtza [Hpmtza = 5‐(2‐pyramidyl)tetrazole‐2‐acetic acid] with TbCl₃ · 6H₂O or DyCl₃ · 6H₂O under solvothermal conditions afforded four mononuclear complexes, [Ln(pztza)₂(H₂O)₆] · pztza · 3H₂O [Ln = Tb ( 1 ), Dy ( 2 )] and [Ln(pmtza)₂(H₂O)₆] · Cl · 3H₂O [Ln = Tb ( 3 ), Dy ( 4 )]. The compounds were characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction. X‐ray diffraction analyses reveal that all structures are mononuclear. The four compounds are self‐assembled to form three‐dimensional networks by hydrogen bonds. The different positions of the nitrogen atom control the coordination mode of the ligands and further influence the crystal structures. Furthermore, the luminescence properties were also investigated at room temperature in the solid state.     

Dinuclear rare-earth picrate complexes based on a multidentate amide ligand: syntheses,crystal structures,and luminescence properties

A new amide-based multidentate ligand, N,N′-1,2-ethanediyl-bis{2-[(N,N-diethylcarbamoyl)methoxy]benzamide} (L) reacts with M(Pic)₃?·?6H₂O to give rare-earth picrate complexes [M₂L₂(Pic)₄(H₂O)₂](Pic)₂ (M = La (1), Nd (2), Eu (3), Gd (4), Tb (5), Dy (6), Yb (7), Y (8)). X-ray single-crystal diffraction analyses indicate that dinuclear complexes 3?·?2C₄H₈O₂, 6?·?2C₄H₈O₂, and 8?·?2CH₃CN are isomorphous. Each metal is nine-coordinate by four oxygen atoms of two ligands, four oxygen atoms of two bidentate picrates, and one water molecule with a distorted monocapped square antiprism. With hydrogen bonds between the free picrate anions and the coordination cations the complexes exhibit 2-D layers. The luminescent properties of 3 [Eu₂L₂(Pic)₄(H₂O)₂](Pic)₂ are described and factors that influence luminescent intensities are also discussed.     

Synthesis and crystal structures of lanthanide complexes with foliage growth regulator: phenoxyalkanoic acid

Reactions of Ln(ClO₄)₃?·?6H₂O (Ln=La(III), Eu(III), Nd(III)), 1,10-phenanthroline (phen) and phenoxyacetic acid (PA) or 2,4-dichlorophenoxyacetic acid (2,4-D) yield [La(PA)₂ (phen)₂]₂(ClO₄)₂ (1), [Eu(2,4-D)₂(phen)₂]₂(ClO₄)₂ (2) and [Nd(2,4-D)₃(C₂H₅OH)] _n (3). Compounds 1–3 are characterized by elemental analyses, IR, UV–Vis, ESI-MS spectra and TGA. 1 is also characterized by ¹H and ¹³C NMR. Single crystal X-ray diffraction analyses reveal that 1 and 2 are binuclear, and 3 has a one-dimensional polymeric structure. The La(III), Eu(III) and Nd(III) are nine-coordinate with a distorted tricapped trigonal-prism geometry.     

3D Heterometallic 3d–4f coordination polymers based on organodisulfonate ligand with isonicotinic acid as a co-ligand: synthesis,crystal structures,photoluminescent and magnetic properties

The hydrothermal reaction of rare earth nitrates, CuCN, 2,7-naphthalenedisulfonate (2,7-nds), and isonicotinic acid (Hina) affords a new family of 3-D heterometallic 3d–4f coordination polymers, [Ln₂Cu(2,7-nds)₂(ina)₄(H₂O)₄]·4H₂O (Ln = Nd (1), Sm (2), Eu (3), Gd (4); 2,7-nds = 2,7-naphthalenedisulfonate, Hina = isonicotinic acid). Complexes 1–4 are structurally characterized by single crystal X-ray diffraction, elemental analysis, FT-IR spectroscopy (IR), powder X-ray diffraction, and thermogravimetric analyses. X-ray crystal structure analyses reveal that 1–4 are isomorphous with dinuclear subunit [Sm₂(ina)₄] binding Cu ions to generate 2-D networks. Such 2-D networks are pillared by linking 2,7-nds ligands to result in the 3-D layer-pillared Ln(III)–Cu(II) coordination architectures. The valence of Cu salts changed in the reaction. In addition, the luminescence properties of 1–3 and the magnetic properties of 3 and 4 have also been investigated.     

Syntheses and crystal structures of four new fpa-metal complexes through in situ ligand reaction

Four new fpa-metal complexes, [Co(fpa)₂(H₂O)₂] (1), [Cu(fpa)₂(H₂O)] (2), [Zn₂(fpa)₄(bpp)₂] _n (3), and {[Zn(bpy)(H₂O)₄]?·?2(fpa)} _n (4), have been synthesized and fully characterized by elemental analyses, IR spectroscopy, single-crystal X-ray diffraction, and thermogravimetric analysis (TGA), (Hfpa?=?2,2-difluoro-2-(pyridine-2-yl)acetate, bpp?=?1,3-bis(4-pyridyl)propane, bpy?=?4,4′-bipyridine). X-ray diffraction analyses reveal that 1 and 2 with 0-D structures are both extended into 3-D supramolecular networks through hydrogen bonds and π···π interactions. Complex 3 with chiral centers possesses a 1-D structure constructed by two kinds of bpp molecules and four kinds of fpa^? molecules with different conformations, with bbp and fpa^? bridging and capped ligands, respectively. In 4, bpy links [Zn(H₂O)₄]²⁺ into a 1-D polymeric cationic chain and uncoordinated fpa^? compensates the framework charge. The results of TGA reveal that fpa^? decomposes through two processes. Both 3 and 4 show strong fluorescence in the solid state at room temperature.     

Effect of the lanthanoid-size on the structure of a series of lanthanoid-anilato 2-D lattices*

Abstract

We report the synthesis and characterization of a series of Ln-based bromoanilato 2-D lattices with dimethyl sulfoxide (DMSO): [Ln₂(C₆O₄Br₂)₃(DMSO)_n]·2DMSO·mH₂O with n = 6 and m = 0 for Ln = La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6) and Gd (7); n = 4 and m = 2 for Ln = Tb (8), Dy (9), Ho (10), Er (11), Tm (12) and Yb (13) (C₆O₄Br₂^2? = 3,6-dibromo-2,5-dihydroxy-1,4-benzoquinone = bromoanilato). The X-ray analysis shows that the largest Ln(III) ions (La-Gd, 1-7) crystallize in the monoclinic P21/n space group (phase I), whereas the smaller Ln(III) ions (Tb–Yb, 8–13) crystallize in the triclinic P-1 space group (phase II). Both phases present a (6,3)-2-D topology but show important differences derived from the different coordination number of the Ln(III) in both phases. In phase I, the Ln(III) ions are nine-coordinate with a tri-capped trigonal prism geometry and rectangular cavities with no solvent molecules. In phase II, the Ln(III) ions are eight-coordinate with a triangular dodecahedral geometry and distorted hexagonal cavities having two water molecules. These differences are due to the lanthanoid contraction. The magnetic properties show that the Ln(III) ions are isolated and do not present any noticeable magnetic interactions as expected for bromoanilato bridges and Ln(III) ions.     

Syntheses,crystal structures,and fluorescence properties of two isomorphic binuclear compounds incorporating N-acetyl-N-phenylglycinate with N-donor co-ligands

In this study, two new isomorphic binuclear compounds, [Ln(µ-NAP)₄(NAP)₂(phen)₂]?·?H₂O (1) and (2) (Ln?=?Eu, Tb, NAP?=?N-acetyl-N-phenylglycinate; phen?=?1,10-phenanthroline), have been synthesized and characterized by infrared spectroscopy, elemental analysis, and X-ray crystallography. These compounds crystallize in a triclinic form with space group Pī with a?=?11.7519(11), b?=?13.4293(12), c?=?14.0686(13)?Å, V?=?1992.7(3)?ų, and Z?=?1. Single-crystal X-ray structural analysis reveals that 1 is binuclear, assembled into a 3-D supramolecular network with self-complementary double hydrogen-bonding interactions and aromatic π–π interactions. Fluorescence properties of 1 and 2 are also discussed.     

Hydrothermal synthesis,structure, and properties of lead(II)-based coordination compounds with R-isophthalic acid (R=OH,CH3)

Three new lead(II)-based coordination polymers, [Pb(5-OH-BDC)] _n ?·?nH₂O (1) (5-OH-BDC?=?5-hydroxyisophthalate), [Pb₂(5-CH₃-BDC)₂] _n (2), and [Pb₂(5-CH₃-BDC)₂(phen)₂] _n ?·?2nH₂O (3) (5-CH₃-BDC?=?5-methylisophthalate, phen?=?1,10-phenanthroline), have been hydrothermally synthesized, structurally determined by single-crystal X-ray diffraction, and characterized by elemental analyses, IR spectra, and thermogravimetric analyses. Both 1 and 2 exhibit 2-D double-layer network structures, while 3 possesses 1-D chain structure bridged by 5-CH₃-BDC. The coordination sphere of Pb(II) in 1 is holodirected, whereas in 2 and 3 the spheres feature hemidirected structures. Fluorescence properties of 1–3 have been investigated in the crystalline state at room temperature.     

Seven-, eight-, and ten-coordinated cerium(III) with highly connective pyridine-2,4,6-tricarboxylate,oxalate, and glycine ligands

Two new 3-D Ce(III) coordination polymers, [Ce_1.3(PTA)₂(Oxa)₂(Gly)(H₂O)₂]·(Gly)4H₂O (1) and [Ce_2.6(PTA)₄(Oxa)₂(H₂O)₁₀]·(MeOH)7H₂O (2) (PTA?=?2,4,6-pyridinetricarboxylate, oxa?=?oxalate and Gly?=?glycine), were synthesized. The oxalate in 1 and 2, generated in situ from the cleavage and chemical rearrangement of PTAH₃, assembled into mixed-ligand networks to generate 3-D frameworks. Single crystal analysis reveals that in both complexes, Ce(III) shows coordination numbers of 7 and 10 in 1 and 8 and 10 in 2. PTA adopts four kinds of coordination modes. These complexes were further characterized using elemental analysis, FTIR spectroscopy and thermogravimetric analysis.     

Synthesis,crystal structure and characterization of a series of complexes constructed from coordinated Lanthanides(III) and the heteropolyanion [SiMo12O40]4−

The reaction of α-[SiMo₁₂O₄₀]^4? with trivalent cations Ln³⁺ and N-methyl-2-pyrrolidone leads to a series of complexes of formula [Ln(NMP)₄(H₂O) _n ]H[SiMo₁₂O₄₀]?·?2NMP?·?mH₂O [where Ln?=?La (1), Pr (2), Nd (3), Sm (4), Gd (5), n?=?4, Ln?=?Dy (6), Er (7), n?=?3. NMP?=?N-methyl-2-pyrrolidone]. The syntheses, X-ray crystal structures, IR, and ESR spectra and thermal properties of the complexes 1, 2, 4, 6, 7 have been reported previously. Here, we report X-ray crystal structures, IR, UV, ESR spectra and thermal properties of the complexes [Nd(NMP)₄(H₂O)₄]H[SiMo₁₂O₄₀]?·?2NMP?·?1.5H₂O (3), and [Gd(NMP)₄(H₂O)₄]H[SiMo₁₂O₄₀]?·?2NMP?·?H₂O (5). In addition, the electrochemical behaviour of this series of complexes in aqueous solution and aqueous-organic solution has been investigated and systematic comparisons have been made. All these complexes exhibit successive reduction process of the Mo atoms.     

Construction of three metal-organic frameworks based on multifunctional T-shaped tripodal ligands (4,5-dicarboxy-1H-imidazol-2-yl)pyridine-1-oxide

Three metal-organic frameworks, [Eu(C₁₀H₆N₃O₅)₃(H₂O)₂]?·?H₂O (1), [Tb(C₁₀H₆N₃O₅)₃(H₂O)₂]?·?H₂O (2), and [Cd(C₁₀H₆N₃O₅)₂Cl₂] (3) based on T-shaped tripodal ligands 3-(4,5-dicarboxy-1H-imidazol-2-yl)pyridine-1-oxide and 4-(4,5-dicarboxy-1H-imidazol-2-yl)pyridine-1-oxide (H₃DCImPyO), have been synthesized by the hydrothermal method and characterized by elemental analysis, IR, and single-crystal X-ray structure analysis. The diverse coordination modes of H₃DCImPyO ligands have afforded the three compounds. Complexes 1 and 2 are isomers and the Ln (Ln?=?Eu or Tb) atoms have coordination number eight with a distorted square prism geometry. The partly deprotonated H₂DCImPyO^? ligands display three different coordination modes to link Ln (Ln?=?Tb or Eu) into 1-D double chains. In 3, Cd(II) lies on an inversion center and displays a slightly distorted octahedral coordination. All three compounds exhibit strong fluorescent emissions in the solid state at room temperature.