A New Zinc(II) Coordination Polymer with a Threefold‐Interpenetrating Diamondoid Net: Synthesis,Crystal Structure and Luminescent Property

The three‐dimensional (3D) coordination polymer, [Zn(dpa)(bib)]_n ( 1 ) [H₂dap = diaphonic acid and bib = 1,4‐bis(imidazol‐1‐yl)benzene], was prepared by hydrothermal synthesis and characterized by single‐crystal X‐ray diffraction, FT‐IR spectroscopy, XRPD, and elemental analysis. Crystal structure determination revealed that complex 1 shows a threefold diamond topological net. Furthermore, the solid‐state luminescent property of [Zn(dpa)(bib)]_n was investigated.     

Synthesis,Structures, and Luminescent Properties of two 3, 5‐Dimethyl‐1‐H‐1, 2,4‐triazole‐Based Zinc Metal‐Organic Frameworks with Aromatic Carboxylate as Coligand

Two metal‐organic frameworks, [Zn(dmtrz)(btrc)_1/3]_n ( 1 ) and [Zn₂(dmtrz)₂(btec)(H₂O)₂]_n ( 2 ) (dmtrz = 3, 5‐dimethyl‐1‐H‐1, 2,4‐triazole, btrc = 1, 3,5‐benzenetricarboxylate, btec = 1, 2,4, 5‐benzenetetracarboxylate), were synthesized by hydrothermal reaction. The crystal structure analysis reveals that compound 1 is a dense 3D framework with Schläfli symbols of {4³}₂{4⁶ · 6⁶ · 8³}₃, which is a loh1 structure. Compound 2 is a 2D network. In addition, the photoluminescence of two compounds were studied in solid state at room temperature, together with their thermal analysis.     

Auxilary Ligand Directed Zinc(II) Metal‐Organic Frameworks with Different Topological Networks

By altering auxiliary N‐donor ligands, two Zn^II compounds, [Zn₃(HL)₂(4,4′‐bipy)₃]_n ( 1 ) and [Zn₄(L)₂(bpp)]_n ( 2 ) (H₄L = 3‐(2′,4′‐dicarboxylphenoxy)phthalic acid, 4,4′‐bipy = 4,4′‐bipyridine, and bpp = 1,3‐bis(4‐pyridyl)propane), were obtained under hydrothermal conditions. Structural analyses revealed that compound 1 features a trinodal (3,4,4)‐connected 3D topological framework, and compound 2 displays a (3,8)‐connected 3D pillar‐layered framework with a tfz‐d topology. Furthermore, the thermal stabilities and the luminescent properties of compounds 1 and 2 were investigated.     

Two Manganese(II) Complexes with a Bulky Fluorene‐Based Carboxylate Ligand: Syntheses,Crystal Structures,and Luminescent Properties

To explore the coordination possibilities of fluorene‐based ligands, two manganese(II) complexes with the ligand 9,9‐dibutyl‐9H‐fluorene‐2,7‐carboxylate ( L ) were synthesized and characterized: [Mn₂( L )₂(DMF)₃]_∞ ( 1 ) and [Mn₂( L )₂(DMF)]_∞ ( 2 ). X‐ray single‐crystal diffraction analyses show that complex 1 has a two‐dimensional (2D) (4,4) structure, whereas complex 2 consits of a three‐dimensional (3D) (4,5)‐connected topology framework. The results indicate that the steric bulk of the fluorene ring in H₂ L plays an important role in the formations of 1 and 2 . Additional pyridine‐based ligands govern the formation of the final frameworks of 2 . Moreover, the luminescent properties of these complexes were briefly investigated.     

Hydrothermal Syntheses,Crystal Structures,and Luminescent Properties of Two Zinc(II) Coordination Polymers

Two zinc(II) compounds, namely [Zn₅(AmTAZ)₆(OH)₂]_n · 2n(NO₃) · 6n(H₂O) ( 1 ) and [Zn₃(AmTAZ)₂(mal)₂]_n ( 2 ) (HAmTAZ = 3‐amino‐1,2,4‐triazole, H₂mal = malonic acid), were hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, and X‐ray diffraction. Single crystal X‐ray diffraction analysis reveals that compound 1 features a 3D framework with dodecahedral cages occupied by free nitrate ions and lattice water molecules and can be reduced into a (4, 8)‐connected flu topological network. Compound 2 features a 3D framework based on two different 1D chains. Moreover, the thermal stabilities and luminescent properties of compounds 1 and 2 were investigated.     

Synthesis,Structure, Luminescent and Thermal Properties of Ytterbium(III) and Dysprosium(III) Complexes with 5‐Sulfoisophthalic Acid Sodium Salt

Two rare earth metal‐organic framework compounds [Ybsip(H₂O)₅] · 3H₂O ( 1 ) and [Dysip(H₂O)₄] ( 2 ) (NaH₂sip: 5‐sulfoisophthalic acid sodium salt) were synthesized hydrothermally, and characterized by single‐crystal X‐ray diffraction, elemental analysis, and FT‐IR spectroscopy. In complex 1 , each Yb^III atom is nine‐coordinate with a distorted monocapped tetragonal prismatic arrangement. Two carboxylate groups of each sip^3– molecule adopt the same μ₁‐η¹:η¹ chelating coordination model connecting two Yb^III atoms. The oxygen atoms of the sulfonate group do not participate in coordination with Yb^III. The whole sip^3– molecule acts as a μ₂ bridge to form an one‐dimensional (1D) chain structure. The 1D chains are linked by hydrogen bonding to generate two‐dimensional layers, and are further combined together to form a three‐dimensional structure. In complex 2 , the Dy^III atom is nine‐coordinate with a distorted monocapped tetragonal antiprismatic arrangement. In each sip^3– anion, two carboxylate groups take the same μ₁‐η¹:η¹ chelating coordination mode, only an oxygen atom of sulfonate group bond to Dy^III ion. The whole ligand sip^3– acts as a μ₃ bridge linking three different Dy^III ions to generate a wave‐like two‐dimensional network with (6,3) topological structure. The two‐dimensional networks are further linked by O–H ··· O hydrogen bonds to form a three‐dimensional structure. The thermal and luminescent properties of both complexes are investigated.     

Syntheses,Structures, and Magnetic Properties of Two Cobalt(II) Metal‐Organic Frameworks Based on Y‐shaped 3,5,4′‐Azobenzenetricarboxylic Acid and Different N‐donor Ligands

Two metal‐organic frameworks, [Co₂(ABTC)(bimh)(OH)] · 2H₂O ( 1 ) and [Co₃(ABTC)₂(dimb)₄]_n ( 2 ) [H₃ABTC = 3,4′,5‐azobenzenetricarboxylic acid, bimh = 1,1′‐(1,4‐hexanediy)bis(imidazole), dimb = 1,4‐bis(1H‐imidazol‐1‐yl)benzene], were prepared under solvothermal conditions and structurally characterized. Complex 1 demonstrates a complicated 3D (3,8)‐connected tfz‐d net with (4³)₂(4⁶.6¹⁷.8⁵) topology. The framework of 2 can be classified as a rare 3D (3,6,6)‐connected net with the Schäfli symbol of (4.6²)₂(4².6¹⁰.8³)(4⁴.6¹⁰.8), and exhibits an intriguing self‐penetrating motif. Meanwhile, the thermal stabilities and magnetic properties for 1 and 2 were also probed.     

Coordination Frameworks based on 3,5‐Bis(imidazole‐1‐yl)­pyridine and Aromatic Dicarboxylate Ligands: Synthesis,Crystal Structures,and Photoluminescent Properties

Three metal coordination polymers [Zn(bdc)(L)(H₂O)]_n ( 1 ), [Co(pta)(L)(H₂O)₂]_n ( 2 ), and [Cd(tda)(L)(H₂O)]_n ( 3 ) [H₂bdc = 1,2‐benzene dicarboxylate acid, H₂pta = terephthalic acid, H₂tda = 2,5‐thiophenedicarboxylic acid, L = 3,5‐bis(imidazole‐1‐yl)pyridine] were synthesized and structurally characterized by IR spectroscopy, elemental analysis, X‐ray powder diffraction, and X‐ray single crystal diffraction. Complex 1 shows a three‐dimensional (3D) structure with cco topology with the symbol 6⁵ · 8, whereas complex 2 features a 3D structure with cds topology with the symbol 6⁵ · 8. Complex 3 has a 2D network constructed by the cadmium atoms bridged through the ligands tda and L. Their X‐ray powder diffraction patterns were compared with the simulated ones. Moreover, their luminescent properties were investigated in the solid state at room temperature, and the thermogravimetric analyses were carried out to study the thermal stability of the 3D networks.     

Syntheses,Structures, and Luminescent Properties of two Cadmium(II) Entangled Frameworks Based on 5‐Bromoisophthalic Acid and Bipyridyl Ligands

Two cadmium(II) entangled frameworks, Cd(BIPA)(bpe)_1.5 ( 1 ) and Cd(BIPA)(bpp)(H₂O) ( 2 ), were prepared by hydrothermal reactions based on rigid 5‐bromoisophthalic acid (H₂BIPA) and two flexible bipyridyl ligands 1, 2‐bis(4‐pyridyl)ethane (bpe) and 1, 3‐bis(4‐pyridyl)propane (bpp). The complexes were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single‐crystal X‐ray diffraction. Complex 1 is a rare example of a polycatenated array of 1D nanotubes, whereas complex 2 exhibits a three‐dimensional twofold interpenetrating diamondoid network. The analysis results reveal that the flexibility of the bipyridyl ligands plays a significant role in the structure of the final products. Moreover, the luminescent properties of the complexes were investigated.     

Hydrothermal Synthesis,Structure, and Optical Properties of Two Nanosized Ln26@CO3 (Ln=Dy and Tb) Cluster‐Based Lanthanide–Transition‐Metal–Organic Frameworks (Ln MOFs)

Two Ln₂₆@CO₃ (Ln=Dy and Tb) cluster‐based lanthanide–transition‐metal–organic frameworks (Ln MOFs) formulated as [Dy₂₆Cu₃(Nic)₂₄(CH₃COO)₈(CO₃)₁₁(OH)₂₆(H₂O)₁₄]Cl ? 3 H₂O ( 1 ; HNic=nicotinic acid) and [Tb₂₆NaAg₃(Nic)₂₇(CH₃COO)₆(CO₃)₁₁(OH)₂₆Cl(H₂O)₁₅] ? 7.5 H₂O ( 2 ) have been successfully synthesized by hydrothermal methods and characterized by IR, thermogravimetric analysis (TGA), elemental analysis, and single X‐ray diffraction. Compound 1 crystallizes in the monoclinic space group Cc with a=35.775(12) Å, b=33.346(11) Å, c=24.424(8) Å, β=93.993(5)°, V=29065(16) ų, whereas 2 crystallizes in the triclinic space group P with a=20.4929(19) Å, b=24.671(2) Å, c=29.727(3) Å, α=81.9990(10)°, β=88.0830(10)°, γ=89.9940(10)°, V=14875(2) ų. Structural analysis indicates the framework of 1 is a 3D perovskite‐like structure constructed out of CO₃@Dy₂₆ building units and Cu⁺ centers by means of nicotinic acid ligand bridging. In 2 , however, nanosized CO₃@Tb₂₆ units and [Ag₃Cl]²⁺ centers are connected by Nic^? bridges to give rise to a 2D structure. It is worth mentioning that this kind of 4d–4f cluster‐based MOF is quite rare as most of the reported analogous compounds are 3d–4f ones. Additionally, the solid‐state emission spectra of pure compound 2 at room temperature suggest an efficient energy transfer from the ligand Nic^? to Tb³⁺ ions, which we called the “antenna effect”. Compound 2 shows a good two‐photon absorption (TPA) with a TPA coefficient of 0.06947 cm GM^?1 (1 GM=10^?50 cm⁴ s photon^?1), which indicates that compound 2 might be a good choice for third‐order nonlinear optical materials.     

Photoluminescence Properties of Lanthanide‐Organic Frameworks (LnOFs) with Thiophene‐2,5‐Dicarboxylate and Acetate

S‐heterocyclic dicarboxylic acid, thiophene‐2,5‐dicarboxylic acid (H₂TDC), was employed to construct a series of lanthanide‐organic frameworks (LnOFs) with coligand acetate, formulated as [Ln(TDC)(OAc)(H₂O)]_n [Ln = Eu ( 1 ), Tb ( 2 ), Gd ( 3 ), Dy ( 4 ), Sm ( 5 )] under hydrothermal conditions. Structure analysis reveals that 1 – 5 have dinuclear 3D metal organic frameworks (MOFs), in which TDC^2– and OAc^– display (κ¹‐κ¹)‐(κ¹–κ¹)‐μ₄ and (κ²‐κ¹)‐μ₂ coordination fashions, respectively. The dehydrated products of all compounds show high thermal stability above 410 °C. As for 1 , 2 , 4 , and 5 , the photoluminescence analyses exhibit characteristic luminescence emission bands of the corresponding lanthanide ions in the visible region. In particular, compound 2 displays bright green luminescence in the solid state with ⁵D₄ lifetime of 0.510 ms and relative high overall quantum yield of 16 %, based on an ideal energy gap between the lowest triplet state energy level of H₂TDC ligand and the ⁵D₄ state energy level of Tb³⁺. The energy transfer mechanisms in compounds 1 and 2 were also discussed.     

Solvent Molecule Controlled Zinc(II) Metal‐Organic Frameworks with Different Topology

Two zinc(II) coordination polymers, namely [Zn₂(bptc)(DMF)₂(H₂O)]_n ( 1 ) and [Zn(bptc)_0.5(DMA)]_n ( 2 ) (H₄bptc = biphenyl‐3,3′,5,5′‐tetracarboxylic acid, DMF = N,N′‐dimethylformamide, DMA = N,N′‐dimethylacetamide), were obtained under solvothermal conditions by varying the reaction solvents. Single crystal X‐ray diffraction analyses revealed that compound 1 features a 3D PtS type framework based on dinuclear [Zn₂O(COO)₂] subunits and compound 2 features a 3D lvt type framework based on paddle‐wheel shaped [Zn₂(COO)₄] subunits. Moreover, the luminescent and thermal stabilities of these two compounds were investigated.     

Synthesis,Crystal Structure,and Properties of the 3D Porous Framework [Zn(INAIP)]·DMA·H2O

A new three‐dimensional (3D) porous framework [Zn(INAIP)] · DMA · H₂O ( 1 ) [INAIP = 5‐(isonicotinamido)isophthalate, DMA = N,N′‐dimethylacetamide] was synthesized by solvothermal methods and characterized by single‐crystal and powder X‐ray diffraction, as well as thermogravimetric analysis. The results of X‐ray diffraction analyses revealed that complex 1 has an unusual 3D architecture with the (3,6)‐connected rutile ( rtl ) topology. The adsorption behavior shows that compound 1 exhibits selective adsorptions of CO₂ over N₂ after the removal of the solvent molecules within the pores.     

Single‐Crystal to Single‐Crystal Linker Substitution,Linker Place Exchange,and Transmetalation Reactions in Interpenetrated Pillared–Bilayer Zinc(II) Metal–Organic Frameworks

A twofold interpenetrated pillared–bilayer framework, {[Zn₃( L )₂( L₂ )(DMF)] ? (18DMF)(6H₂O)}_n ( 1 ), has been synthesized from the ligands tris(4′‐carboxybiphenyl)amine ( H₃L ) and 1,2‐bis(4‐pyridyl)ethylene ( L₂ ). The structure contains [Zn₃(COO)₆] secondary building units (SBUs), in which three Zn^II ions are almost linear with carboxylate bridging. This framework undergoes reversible pillar linker substitution reactions at the terminal Zn^II centers with three different dipyridyl linkers of different lengths to afford three daughter frameworks, 2 – 4 . Frameworks 2 – 4 are interconvertible through reversible linker substitution reactions. Also, competitive linker‐exchange experiments show preferential incorporation of linker L₃ in the parent framework 1 . The larger linker L₅ does not undergo such substitution reactions and framework 5 , which contains this linker, can be synthesized solvothermally as a twofold interpenetrated structure. Interestingly, when framework 5 is dipped in a solution of L₃ in DMF, linker substitution takes place as before, but linker L₅ now moves and diagonally binds two Zn^II centers to afford 6 as a nonpenetrated single framework. This linker place exchange reaction is unprecedented. All of these reactions take place in a single‐crystal to single‐crystal (SC‐SC) manner, and have been observed directly through X‐ray crystallography. In addition, each 3D framework undergoes complete copper(II) transmetalation.     

Synthesis,Structure and Magnetic Property of a Cobalt(II) Metal‐Organic Framework

The three‐dimensional (3D) porous cobalt(II) metal‐organic framework (MOF), [Co₃(L)₂(DMA)₂(MeOH)₂ · 4(DMA) · 6(MeOH)]_n ( 1 ) [L = fully deprotonated 2,7‐bis(4‐benzoic acid)‐N‐(4‐benzoic acid) carbazole, DMA = N,N‐dimethylacetamide], was synthesized by hydrothermal reaction. Based on X‐ray single‐crystal diffraction, structural analysis indicates that complex 1 crystallizes in the monoclinic C2/c space group. Complex 1 possesses a 3,6‐connected three‐dimensional (3D) topological structure with a point symbol of {4² · 6}₂{4⁴ · 6² · 8⁷ · 10²} when a trinuclear Co^II cluster was regarded as 6‐connected node and the organic ligands could be regarded as 3‐connected linkers between the 6‐connected nodes. The framework structure exhibits a one‐dimension (1D) channel with an accessible void of 4223.0 ų, amounting to 42.8 % of the total unit‐cell volume (9862.0 ų). Moreover, the magnetic properties of complex 1 were studied.     

Controlled Construction of Metal–Organic Frameworks: Hydrothermal Synthesis,X‐ray Structure,and Heterogeneous Catalytic Study

The role of pH in the formation of metal–organic frameworks (MOFs) has been studied for a series of magnesium‐based carboxylate framework systems. Our investigations have revealed the formation of five different zero‐dimensional (0D) to three‐dimensional (3D) ordered frameworks from the same reaction mixture, merely by varying the pH of the medium. The compounds were synthesized by the hydrothermal method and characterized by single‐crystal X‐ray diffraction. Increase of the pH of the medium led to abstraction of the imine hydrogen from the ligand and a concomitant increase in the OH^? ion concentration in the solution, facilitating the construction of higher dimensional framework compounds. A stepwise increase in pH resulted in a stepwise increase in the dimensionality of the network, ultimately leading to the formation of a 3D porous solid. A gas adsorption study of the 3D framework compound confirmed its microporosity with a BET surface area of approximately 450 m² g^?1. Notably, the 3D framework compound catalyzes aldol condensation reactions of various aromatic aldehydes with acetone under heterogeneous conditions.     

Design,Synthesis, and X‐Ray Crystal Structure of a Fullerene‐Linked Metal–Organic Framework

Given the unique structural and electronic properties of C₆₀, metal–organic frameworks (MOFs) containing C₆₀ linkers are expected to exhibit interesting characteristics. A new hexakisfullerene derivative possessing two pairs of phenyl pyridine groups attached to two methano‐carbon atoms located at the trans‐1 positions was designed and synthesized. The four pyridyl nitrogen atoms define a perfectly planar rectangle. This new C₆₀ derivative was used to assemble the first fullerene‐linked two‐dimensional MOF by coordination with Cd²⁺.     

Bismuth(III) based Metal Organic Frameworks: Luminescence,Gas Adsorption,and Antibacterial Studies

Bi^III‐MOFs 1 – 4 were prepared via solvothermal method using four organic linkers; 2‐mercapto‐3‐methyl‐4‐thiazoleacetic acid (H₂MMTA), 2,6‐naphthalenedicarboxylic acid (2,6‐NDA), 4,6‐dihydroxy‐2‐mercaptopyrimidine (H₂DMP), and 4‐mercaptobenzoic acid (H₂MBA), respectively. The resulting MOFs were structurally/morphologically characterized by UV/Vis, AAS/ICP‐MS, Fourier transform infrared spectroscopy (FT‐IR), ¹H NMR, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and powder X‐ray diffraction technique. All these MOFs showed good luminescence properties exhibiting blue luminescence. N₂ gas adsorption isotherms of 1 – 4 confirmed the porosity of these frameworks. In order to evaluate the effect of metal ion upon chelation, the free organic linkers and respective MOFs were screened for their antibacterial potential against some pathogenic bacteria and appreciable activity was observed.