Auxiliary ligand-assisted two novel one-dimensional indium coordination polymers: Synthesis,crystal structures and photoluminescence characterization effected by solvent and temperature

Two new indium coordination polymers (CPs) with mixed-ligand formulated as {[In(1,4-bda)_1.5(phen)]·2H₂O}_n (In1) and {In(1,4-bda)(2,2′-bipy)Cl}_n (In2) (1,4-H₂bda = 1,4-benzenedicarboxylic acid; phen = 1,10-phenanthrolin; 2,2′-bipy = 2,2′-bipyridine) have been synthesized and characterized by single-crystal X-ray diffraction, infrared (IR), elemental analysis and thermal gravimetric analyses (TGA). In1 exhibits one-dimensional (1D) ladder chain, which further forms three-dimensional (3D) structure with π⋯π stacking interaction. Formation of 3D compact supramolecular framework in In2 is generated through C–H…Cl hydrogen bonding contacts and π⋯π stacking interaction. The photoluminescence (PL) characterizations to In1 and In2 affected by solvent and temperature are studied in detail. Thermogravimetric curves showed that In1 and In2 start to undergo phase transition until ca. 450 °C and 495 °C, respectively.     

A 3D Cu(II) coordination polymer constructed from BIBP (BIBP = 5,5′-bis(1H-imidazol-1-yl)-2,2′-bithiophene) ligand with semiconductive property

Hydrothermal reaction of Cu(NO₃)₂·3H₂O with BIBP and H₂hfipbb at 105 °C yielded a novel 3D Cu(II) coordination polymer, {[Cu₂(BIBP)_0.5(hfipbb)₂(CH₃CN)]·5H₂O}_n (1) [BIBP = 5,5′-bis(1H-imidazol-1-yl)-2,2′-bithiophene, H₂hfipbb = 4,4′-(hexafluoroisopropylidene)bis(benzoic acid)]. Compound 1 displays a 3D 2-fold interpenetrating framework with {4⁴.6⁶} sqp topology, containing interesting ⋯LRLR⋯ double helical chains. The compound 1 was characterized by IR spectra, elemental analysis, thermal analysis and single crystal X-ray diffraction. In addition, solid-state UV–vis spectra experiment shows that compound 1 exhibits semiconductive property with a band gap of 2.46 eV.     

Two d10 coordination polymers based on 4,4′-(hexafluoroisopropylidene)diphthalic acid: Syntheses,structures and physical properties

Two novel coordination polymers, [Zn₂(FA)(4,4′-bipy)₂]·2H₂O (1) and Cd₂(FA)(2,2′-bipy) (2), (H₄FA = 4,4′-(hexafluoroisopropylidene)diphthalic acid, 4,4′-bipy = 4,4′-bipyridine, 2,2′-bipy = 2,2′-bipyridine), have been synthesized under hydrothermal conditions, and their structures were determined by single-crystal X-ray diffraction. Polymer 1 features an unusual three-dimensional (3D) network with (4 · 6² · 8³)(4² · 6² · 8²) topology. Polymer 2 has a complicated 3D framework and crystallizes in non-centrosymmetric space group (Fdd2) belonging to polar point group (C_2v), which displays a strong SHG response and ferroelectric properties. Moreover, the luminescent properties of 1 and 2 have also been investigated.     

Hydrothermal synthesis and structure of di-copperII-complex substituted monovacant polyoxotungstate with a 1D chain structure

A novel di-copper^II-complex substituted monovacant Keggin polyoxotungstate [Cu(2,2′-bpy)(H₂O)][H₂PW₁₁O₃₉Cu₂(2,2′-bpy)₂(H₂O)(OH)] · 1.5H₂O (1) (2,2′-bpy = 2,2′-bipyridine) with a 1D polymeric chain has been hydrothermally synthesized and structurally characterized. To our knowledge, 1 is the rare magnetic di-transition metal-complex substituted monovacant Keggin polyoxotungstate with a unique 1D dual-bridging chain structure. Its magnetic behavior has been quantitatively analyzed by the Bleaney–Bowers equation, indicating the presence of weak antiferromagnetic interactions within dinuclear Cu^II centers.     

Two 2D metal–organic frameworks based on 2,2′-bibenzimidazole ligand with (6,3) net topology

Two 2D metal–organic frameworks (MOFs), {[Zn₄(Hbbim)₄(bbim)₂] 2H₂O}_n (1) and [Cd₂(Hbbim)₂(bbim)]_n (2) (H₂bbim = 2,2′-bibenzimidazole) were obtained by solvothermal reaction and characterized by single crystal X-ray diffraction analysis. Different metal ions, Cd(II)/Zn(II), adopt very different coordination geometries though two title compounds both have a 2D honeycomb network with (6,3) topology. The frameworks of compounds 1 and 2 are stable below 360 °C and 475 °C, respectively. Solid-state luminescent spectroscopy of compound 2 exhibits an emission peak at 407 nm.     

Two helical one-dimensional copper(II) coordination polymers based on N-(2-hydroxylbenzyl)glycine and N-(2-hydroxylbenzyl)-l-alanine: Syntheses,crystal structures and magnetic studies

Two new helical Cu(II) coordination polymers, [Cu(2,2′-bpy)(Hsgly)]Cl · 2H₂O(H₂sgly = N-(2-hydroxylbenzyl)glycine) (1) and [Cu(2,2′-bpy)(Hsala)](NO₃) · 2H₂O(H₂sala = N-(2-hydroxylbenzyl)-l-alanine) (2) were synthesized. Single crystal X-ray diffraction analysis indicated that both complexes showed helical chains arrangement of Cu(II) centers bridged by carboxyl groups. The magnetic measurements showed complex 1 exhibited ferromagnetic interaction while there was no interaction between the Cu(II) centers in complex 2.     

Syntheses,structures and magnetic property of two copper complexes with cyclic dimer and 2D herringbone-like network built from helical motif

Two copper(II) complexes, Cu₂{3,5-(NO₂)₂sal}₂(2,2′-bipy)₂ · 0.5H₂O (1) and [Cu₂{3,5-(NO₂)₂sal}₂(4,4′-bipy)(H₂O)₂]_n (2) (3,5-(NO₂)₂sal = 3,5-dinitrosalicylate, 2,2′-bipy = 2,2′-bipyridine, 4,4′-bipy = 4,4′-bipyridine), were synthesized by hydrothermal reactions and characterized by single crystal X-ray analysis. There are discrete cyclic binuclear structure in 1 and 2D herringbone-like network structure in 2, although bridging ligand 3,5-(NO₂)₂sal in 1 and 2 has same coordination model. Variable temperature magnetic measurement reveals small ferromagnetic interactions in complex 1.     

A palladium(II) complex of 4′-(4-pyridyl)-2,2′:6′,2″-terpyridine: Lattice control through an interplay of stacking and hydrogen bonding effects

The complex [Pd(1)Cl]Cl where 1 =  4′-(4-pyridyl)-2,2′:6′,2″-terpyridine is reported. The single crystal structure of [Pd(1)Cl]Cl · 3H₂O · DMF features rows of columns of [Pd(1)Cl]⁺ cations which are supported by Pd⋯Pd interactions (3.367(1) and 3.440(1) Å) and separated by hydrogen-bonded 4.8² nets of water molecules and Cl⁻ ions.     

Synthesis,structure and characterization of neat Zn2(OH)2 diamond-core chains linked through 2,2′,4,4′-biphenyl-tetracarboxylate

Reaction of 2,2′,4,4′-biphenyltetracarboxylic acid (2,4-H₄bptc), Zn(NO₃)₂ · 6H₂O in the presence of NaOH hydrothermally at 180 °C affords the first 2,4-H₄bptc complex [Zn₃(μ₃-OH)₂(2,4-bptc)]_n · 2nH₂O (1). Crystal structure indicates that 1 is Zn₂(OH)₂ diamond-core chains linked through 2,2′,4,4′-biphenyltetracarboxylate. 1 was characterized by TG, IR and fluorescence spectra. 1 is the first example of 2,4-H₄bptc complex and also first neat Zn₂(OH)₂ diamond-core chains.     

Synthesis,structure and magnetic property of a cyanamido bridged trinuclear copper complex

An unusual μ_1,1,3-cyanamido bridged trinuclear copper complex, [(2,2′-bpy)₆Cu₃(NCN)](ClO₄)₄·H₂O (1) (2,2′-bpy = 2,2′-bipyridine), has been synthesized and structurally characterized. Magnetic studies show the existence of large antiferromagnetic coupling between the copper(II) ions.     

Novel 3-dimensional sixfold interpenetrating diamondoid networks of copper(I) coordination polymers of polypyridyl ligands – Syntheses,characterization and crystal structures

Two new coordination polymers [Cu(L¹)₂]_n(ClO₄)_n·2nH₂O (1), [Cu(L²)₂]_n(ClO₄)_n·2nH₂O (2) of polydentate imine/pyridyl ligands, L¹ and L² with Cu(I) ion have been synthesized and characterized by single crystal X-ray diffraction studies, elemental analyses, IR′ UV–vis and NMR spectroscopy. They represent 3-dimensional, sixfold interpenetrating diamondoid network structures having large pores of dimension, 35 × 21 Å² in 1 and 38 × 19 Å² in 2, respectively.     

Linear trinuclear manganese(II) complexes: crystal structures and magnetic properties

Two new trinuclear manganese(II) complexes, [Mn₃(O₂CCH(CH₃)₂)₆(N–N)₂] (N–N is 1,10′-phenanthroline (1) and 2,2′-bipyridine (2)) have been prepared and fully characterized. Single crystal X-ray diffraction analysis confirmed a linear arrangement of three Mn(II) centers bridged by six isobutyric carboxylate groups. The magnetic measurements showed that both complexes exhibit an S_T = 5/2 spin ground state induced by antiferromagnetic interactions between the Mn(II) sites: J/k_B = −2.31(2) and −2.67(2) K for 1 and 2, respectively.     

PMMA-supported hybrid materials doped with highly near-infrared (NIR) luminescent neutral trikis-β-diketonate Yb3 + complex

Based on self-assembly of a trifluorinated and acylpyrazole-modified β-diketonate ligand HL ((Z)-3-methyl-1-phenyl-4-(2,2,2-trifluoro-1-hydroxyethylidene)-1H-pyrazol-5(4H)-one), LnCl₃⋅ 6H₂O (Ln = La, Yb or Gd) and 2,2′-bpy (2,2′-bipyridine), three trikis-β-diketonate complexes [Ln(L)₃(2,2′-bpy)] (Ln = La, 1; Ln = Yb, 2 or Ln = Gd, 3) were obtained, respectively. Further through physical doping, the series of PMMA-supported hybrid materials PMMA@[Ln(L)₃(2,2′-bpy)] with high thermal stability and good film-forming property are obtained. Especially for PMMA@2, the doping also causes the improved NIR luminescent property (Φ_em = 0.97%) in comparison to the individual Yb^3 +-β-diketonate complex 2 (Φ_em = 0.81%) even up to a concentration of 200:1.     

Syntheses and structures of cadmium(II) and cobalt(II) coordination polymers based on 1,1′-(2,2′-oxybis(ethane-2,1-diyl))bis(1H-imidazole) and carboxylate ligands

Two novel coordination polymers containing Cd(II) and Co(II) metals, connected via 1,1′-(2,2′-oxybis(ethane-2,1-diyl))bis(1H-imidazole) (L) ligand, have been synthesized. Compound [Cd(L)₂(p-BDC)] · 2H₂O (1) (p-BDC = 1,4-benzenedicarboxylate anion) is a three-dimensional interdigitated supramolecular architecture. Compound [Co(L)(BTCA)_0.5] (2) (BTCA = 1,2,3,4-butanetetracarboxylate anion) possesses a unique (3,4)-connected 3D framework with (8³)₂(8⁵ · 10) topology.     

Luminescent mononuclear Pt(II) chloride complexes with C-linked 2,2′-bipyridyl tetrazole terdentate chelating ligands

Two new luminescent mononuclear Pt(II) chloride complexes possessing C-linked 2,2′-bipyridyl tetrazole terdentate chelating ligands, namely, Pt(tbpy)Cl (1) and Pt(tmbpy)Cl (2) (tbpyH = 6-(1H-tetrazol-5-yl)-2,2′-bipyridine; tmbpyH = 6-(1H-tetrazol-5-yl)-4,4′-dimethyl-2,2′-bipyridine), have been synthesized and characterized. Complex 2 adopts a distorted square-planar geometry with a mono-anionic terdentate chelate tmbpy, and it presents a zigzag head-to-tail stacking array along the a axis with alternating Pt⋯Pt separations of 3.415 and 5.469 Å. For 2, a moderately intensive broad absorption band appears at 350–425 nm in dilute DMF solution, most likely assigned as the metal-to-ligand charge transfer ¹MLCT (Pt(5d) → tmbpy) transition, mixed with some halide-to-ligand charge transfer ¹XLCT (Cl → tmbpy) and intraligand (IL) ¹ππ* transitions inside tmbpy. It is demonstrated that the solubilities and luminescence properties of 1 and 2 are markedly influenced by the substituents in the 4 and 4′-positions of the 2,2′-bipyridyl ring. The solid-state emissions of 1 and 2 are perhaps best attributable to the ³MMLCT/³XLCT/³IL states, as supported by TD-DFT calculation of 2.     

Assembly of one 2D layer and two 3D pillared-layer structures derived from metal ions and 5-(pyridin-4-yl)isophthalic acid with or without pillars

Three new coordination polymers, [Mn(L)(H₂O)₂]₂·5H₂O (1), [Cu(L)(4,4′-bipy)]₂·H₂O (2) and [Pb(L)(4,4′-bipy)_0.5] (3) (H₂L = 5-(pyridin-4-yl)isophthalic acid; 4,4′-bipy = 4,4′-bipyridine) have been synthesized and characterized by IR, thermogravimetric analysis, X-ray powder diffraction and X-ray single crystal diffraction. Complex 1 shows a 2D layer structure which stacks with the other ones to form 1D channels to hold 1D water chains. Complex 2 displays a 3D + 3D → 3D polycatenation network. 3 shows a unique 2D + 2D → 3D polycatenation net in which each Pb center has a hemidirected coordination geometry due to the existence of “inert pair effect”. The thermal and luminescent properties of 1–3 were also examined.     

Formation of one-dimensional metal–water chain containing discrete water octamers

Discrete water octamers containing 1D metal–water chains have been observed in the complex of [Tb₂(bpdc)(Pic)₂(OH₂)₁₂](Pic)₂ · 4H₂O · (CH₃OH)₂ (Pic = picrate, bpdc = 2,2′-bipyridine-3,3′-dicarboxylate) (1). The water clusters are trapped by the cooperative association of coordinate interactions as well as hydrogen bonds. The intermolecular interaction is robust enough to really act as a ‘supramolecular glue’ to assemble the binuclear coordination complex and picratol into three-dimensional arrays.     

Two novel grid networks based on Keggin-type polyoxometalate clusters assembled through weak Cu⋯O interactions

Two novel grid networks based on Keggin-type polyoxoanion, formulated [Cu(2,2′-bipy)₂](HPMo₁₂O₄₀) · H₂O (1) and [Cu(2,2′-bipy)₂](HPW₁₂O₄₀) · H₂O (2) have been synthesized hydrothermally and characterized by elemental analyses, IR, EPR and X-ray single crystal diffraction. 1 is a 2D grid network built by the interconnection of bisupporting polyoxoanion clusters assembled through weak Cu⋯O interactions. The EPR spectrum of 1 indicates that its unpaired electrons are placed in d_x²−y² orbital of the ground state of Cu(II). Compound 2 is isostructural with compound 1.     

Synthesis,structure and unprecedented self-assembly strategy of two six-membered Zn–organic macrocycles

Two novel cyclohexane-like metallamacrocycles [ZnCH₃COO(L)]₆·solvent (1) and [Zn(HNO₃)(L)]₆·solvent (2) (HL = 4′-(4-carboxyphenyl)-2,2′:6′,2″-terpyridine) have been synthesized under hydrothermal conditions and characterized by IR spectra, single crystal X-ray diffraction, PXRD analysis, thermogravimetric analysis. The X-ray single crystal diffraction indicates that the self-assembly of the metallamacrocycle generates a fused-ring network that is further assembled into a 3D structure with 1D suprachannels. In particular, a designed self-assembly strategy has been applied to achieving six-membered Zn–organic metallamacrocycles unprecedentedly.     

Dinuclear cadmium(II) thiolate complexes bearing urea groups: Synthesis,characterization, photophysical properties and anion binding studies

A series of cadmium(II) thiolate complexes with urea units [(bpy)₂Cd(μ-SC₆H₄-4-NHC(O)NHC₆H₄-R-4)]₂(ClO₄)₂ (R = NO₂ (1), Cl (2), H (3); bpy = 2,2′-bipyridine), have been synthesized and characterized. The crystal structure of 3·(DMF)₂ has been determined by X-ray diffraction. The photophysical properties and anion binding properties of 1–3 have been studied.