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.     

Four Gadolinium Coordination Compounds Derived from Various Tetrazole‐Containing Carboxylic Acids

Reactions of four different tetrazole‐containing carboxylic acids with GdCl₃ · 6H₂O, produced the coordination compounds, [Gd₄(pytza)₅(H₂O)₁₀(μ‐O) Cl] · 4H₂O · 2Cl ( 1 ) [pytza = 2‐(5‐(pyridine‐4‐yl)‐2H‐tetrazole‐2‐yl)acetato], [Gd(pztza)₂(H₂O)₆] · pztza · 3H₂O ( 2 ), [pztza = 2‐(5‐(pyrazin‐2‐yl)‐2H‐tetrazol‐2‐yl) acetato], [Gd(pmtza)₂(H₂O)₆]Cl · 2H₂O ( 3 ), [pmtza = 2‐(5‐(pyrimidyl‐2‐yl)‐2H‐tetrazol‐2‐yl) acetato], and Gd(tzpya)₂(H₂O)₅]Cl · 4H₂O ( 4 ) [tzpya = 2‐(4‐(5H‐tetrazol‐5‐yl)pyridin‐1(4H)‐yl) acetato]. The compounds were structurally characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction. X‐ray diffraction analysis reveals that compound 1 displays a 2D single layered network and compounds 2 – 4 are mononuclear. Compounds 1 – 4 are self‐assembled to form 3D networks by hydrogen bonding interactions. Furthermore, the luminescent properties in the solid state at room temperature were investigated.     

Structurally Different Calcium(II) Complexes with 5‐Substituted Tetrazole Ligands

Three different tetrazole‐carboxylate ligands, Hpymtza, Hpytza, and H₂dtzeda were chosen to be reacted with Ca(NO₃)₂ · 4H₂O, resulting in the formation of three coordination compounds, [Ca(pymtza)₂(H₂O)₄] ( 1 ), [Ca(pytza)₂(H₂O)₂] ( 2 ), and [Ca(dtzeda)(H₂O)₂] ( 3 ) [Hpymtza = 5‐(2‐pyrimidyl)tetrazole‐1‐acetic acid, Hpytza = 5‐(3‐pyridyl)tetrazole‐2‐acetic acid, and H₂dtzeda = 1, 2‐bis(tetrazol‐5‐yl)ethane‐N1, N1′‐diacetic acid]. X‐ray diffraction analysis revealed that compound 1 displays a mononuclear structure, compound 2 is a one dimensional zigzag chain structure, whereas 3 shows a three‐dimensional structure. The structures were controlled by not only the different substituents of the tetrazolyl ring, but also the complementary hydrogen bonds. Furthermore, the luminescence properties of compounds 1 – 3 were investigated at room temperature in the solid state. These emissions can be tentatively attributed to the ligand centered emission.     

Coordination Architectures of Lanthanum Complexes Based on Bifunctional 5‐Substituted Tetrazolecarboxylate Ligands

Three complexes of bifunctional 5‐substituted tetrazolatecarboxylate ligands [2‐(5‐(pyrazin‐2‐yl)‐2H‐tetrazol‐2‐yl)acetic acid (Hpztza), 3‐(5‐amino‐2H‐tetrazol‐1(5H)‐yl)propanoic acid (Hatzp), and N,N′‐bis(tetrazol‐5‐yl)anime‐N2,N2′‐diacetic acid (H₂datza)], namely a mononuclear structure [La(pztza)₂(H₂O)₅] · 4H₂O · pztza ( 1 ), a 1D polymeric chain structure [La₂(atzp)₄(H₂O)₈] · 2NO₃ · 2H₂O ( 2 ), and a 2D layer network [La(datza)(H₂O)₃] · 4H₂O ( 3 ) were prepared and structurally characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction. The structures of these complexes are controlled not only by the number and different coordination modes of the tetrazole‐carboxylate ligands but also the different 5‐substituents of the tetrazole ring. The complexes show ligand‐centered luminescence at room temperature in the solid state. The obvious enhancements in luminescence make these complexes to be the potential materials for optical use.     

pH Dependent Synthesis of NdIII Coordination Compounds Based on Bifunctional 5‐(4‐Pyridyl)tetrazole‐2‐acetic Acid

The Nd^III coordination compounds [Nd(4‐pytza)₃(H₂O)₂] · 2H₂O ( 1 ) and [Nd(4‐pytza)₂(H₂O)₄]Cl · 2H₂O ( 2 ) [H4‐pytza = 5‐(4‐pyridyl)tetrazole‐2‐acetic acid] were synthesized by reactions of K4‐pytza and NdCl₃ · 6H₂O at different pH values. Single crystal X‐ray diffraction analysis reveals that 4‐pytza ligands in 1 in a μ_1,3‐COO syn‐syn or μ_1,1,3‐COO bridging mode coordinate to two central Nd^III atoms to display a dinuclear unit, which is connected by one of these 4‐pytza ligands acting in end‐to‐end bridging mode to form a 1D ladder‐like chain. Different from 1 , each 4‐pytza in 2 with a μ_1,3‐COO syn‐anti bridging mode coordinates to two Nd^III atoms to display a 1D zigzag chain. Furthermore, the luminescence properties of 1 and 2 were investigated at room temperature in the solid state.     

A lvt‐type Framework [Cu2(tza)4]·ClO4·4H2O Derived from 1H‐tetrazole‐1‐acetic Acid

The reaction of 1H‐tetrazole‐1‐acetic acid (Htza) and perchloric acid with cuprous chloride with slow evaporation at room temperature gave a novel 3D porous Cu^II coordination polymer, [Cu₂(tza)₄] · ClO₄ · 4H₂O ( 1 ), (tza = tetrazole‐1‐acetate). The structure exhibits an unusual 3D microporous coordination framework built up by four coordinated Cu^II nodes and bidentate bridging tza ligands with lvt‐type topology. Furthermore, the magnetic properties of complex 1 were also investigated.     

Three new manganese(II) coordination complexes based on tetrazole carboxylate ligands

Reactions of three tetrazole carboxylate ligands, namely 5-(4-pyridyl)tetrazole-2-acetic acid (Hpytza), 1,3,5-tris(tetrazol-5-yl)benzene-N2,N2′,N2″-triacetic acid (H₃tzpha) and 5-aminotetrazole-1-propanoic acid (Hatzpa) with Mn(NO₃)₂·6H₂O in the presence of KOH afforded three new complexes, [Mn(pytza)₂] (1), [Mn₃(tzpha)₂(H₂O)₁₂]·2CH₃OH·10H₂O (2) and [Mn(atzpa)₂(H₂O)₂] (3), respectively. These complexes were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Complex 1 displays a three-dimensional network while 2 and 3 show one-dimensional chains. Furthermore, the luminescence properties of these complexes were investigated at room temperature in the solid state.     

Synthesis and anticancer property of one Ce(III) compound based on 5-(2-pyrazinyl)tetrazole-2-acetic acid

Mononuclear [Ce(pztza)₂(H₂O)₆](pztza)·H₂O (1) (pztza = 5-(2-pyrazinyl)tetrazole-2-acetato) has been prepared and characterized by IR, elemental analysis and single-crystal X-ray diffraction. PEG_-5000 (poly(ethyleneglycol_-5000)) coated [Ce(pztza)₂(H₂O)₆](pztza)·H₂O nanoparticles (NPs) can disperse into distilled water. In vitro study on Hela cells shows that Hpztza is nontoxic while [Ce(pztza)₂(H₂O)₆](pztza)·H₂O NPs show high toxicity with half-maximal inhibitory concentration (IC₅₀) of 17 μg/mL (1.93 × 10^?5 M). In addition, such NPs can inhibit the migration of Hela cells effectively.     

Crystal Structures and Luminescent Properties of Two Zinc(II) Coordination Compounds with a β‐Diketonate Derivative Ligand

The β‐diketonate derivative ligand [H₂L = 6‐(3‐hydroxy‐1‐oxo‐3‐pyrryl‐2‐propen‐1‐yl)‐2‐pyridinecarboxylic acid] and its zinc(II) coordination complexes, [Zn(H₂L)Cl₂] · (EtOH)(H₂O) ( 1 ) and [Zn₄(L)₄(H₂O)₂] · 5H₂O ( 2 ), were prepared and characterized by elemental analysis, IR and NMR spectroscopy, and single‐crystal X‐ray diffraction. Complex 1 is a mononuclear structure. Complex 2 is a [2 × 2] grid tetranuclear structure. The luminescent properties of the free ligand H₂L and complexes 1 and 2 in methanol solution were studied.     

Synthesis and anticancer property of one Fe(II) compound based on 5-(3-pyridyl)tetrazole-2-acetic acid

Abstract

Tetrazole-carboxylate ligands are universally considered as multi-functional candidates for the construction of coordination architectures. A 1-D [Fe(pytza)₂(H₂O)₂]_n·2nH₂O (pytza = 5-(3-pyridyl)tetrazole-acetato) has been prepared. In vitro study on Hela cells show that Hpytza is naturally nontoxic while [Fe(pytza)₂(H₂O)₂]_n·2nH₂O shows high toxicity with a half-maximal inhibitory concentration (IC₅₀) of 6.3?×?10^?5 M. In addition, the compound can effectively inhibit the migration of Hela cells.     

Four Complexes with the Rigid Ligand 1,4‐Bis(1H‐imidazol‐4‐yl)benzene and Varied Carboxylate Ligands

Four metal‐organic coordination polymers [Co₂(L)₃(nipa)₂]·6H₂O ( 1 ), [Cd(L)(nipa)]·3H₂O ( 2 ), [Co(L) (Hoxba)₂] ( 3 ) and [Ni₂(L)₂(oxba)₂(H₂O)]·1.5L·3H₂O ( 4 ) were synthesized by reactions of the corresponding metal(II) salts with the rigid ligand 1,4‐bis(1H‐imidazol‐4‐yl)benzene (L) and different derivatives of 5‐nitroisophthalic acid (H₂nipa) and 4,4′‐oxybis(benzoic acid) (H₂oxba), respectively. The structures of the complexes were characterized by elemental analysis, FT‐IR spectroscopy and single‐crystal X‐ray diffraction. Complexes 1 and 3 have the same one‐dimensional (1D) chain while 2 is a 6‐connected twofold interpenetrating three‐dimensional (3D) network with α ‐Po 4¹²·6³ topology based on the binuclear Cd^II subunits. Compound 4 features a puckered two‐dimensional (2D) (4,4) network, and the large voids of the packing 2D nets have accommodated the uncoordinated L guest molecules. An abundant of N–H···O, O–H···O and C–H···O hydrogen bonding interactions exist in complexes 1–4 , which contributes to stabilize the crystal structure and extend the low‐dimensional entities into high‐dimensional frameworks. Lastly, the photoluminiscent properties of compounds 2 were also investigated.     

Synthesis and Crystal Structure of Novel Coordination Polymers with Nitrilotripropionic Acid

A novel three‐dimensional (3D) lanthanide‐organic framework [Pr₃(NTP)₃(H₂O)₆] · 10H₂O ( 1 ), (H₃NTP = 3,3′,3′‐nitrilotripropionic acid) was synthesized and characterized by elemental analyses, IR spectroscopy, and X‐ray diffraction analyses. The results show that complex 1 is connected through NTP ligands to form a 3D network with microchannels. The coordination mode of the NTP ligand was found for the first time. In order to investigate the temperature effects on controlling the dimensionality of the complexes, another two complexes, namely, [Nd(NTP)(H₂O)₂] · H₂O · HBr ( 2 ) and [Pr(H₂O)][⁺NH₃(CH₂CH₂COO^–)][OOCCOO]_1.5 ( 3 ) were synthesized and characterized. Notably, in complex 3 , the NTP ligand lost its two arms because of the high temperature. Furthermore, the thermogravimetric analyses of the three complexes are discussed in detail.     

Three Coordination Polymers based on 3,5‐Bis(imidazole‐1‐yl)pyridine and Benzoic Acid: Synthesis,Crystal Structures and Photoluminescent Properties

Three metal coordination polymers {[Co(L)₂(H₂O)₂]²⁺ · 2NO₃^–}_n ( 1 ), {[Mn(L)₂(H₂O)₂]²⁺ · 2Cl^– · 3H₂O}_n ( 2 ), and [ZnL(ba)₂]_n ( 3 ) [L = 3,5‐bis(imidazole‐1‐yl)pyridine and Hba = benzoic acid] were synthesized and structurally characterized by IR spectroscopy, elemental analysis, X‐ray powder diffraction, and X‐ray single crystal diffraction. Complex 1 shows a one‐dimensional (1D) chain structure. Adjacent chains are connected by hydrogen bonding and nitrate groups to form a 3D network. Complex 2 features a 2D layer structure. A three‐dimensional network is constructed through the cluster consisting of two chloride ions and three water molecules. Complex 3 shows a 1D zigzag chain structure that further twists together to form a 3D network. The X‐ray powder diffraction patterns were compared with the simulated ones. Moreover, the luminescent properties of 1 – 3 were investigated in the solid state at room temperature, and the thermogravimetric analyses were carried out to study the thermal stability of the three complexes.     

pH Dependent Synthesis of Two Manganese Compounds based on 5‐(2‐Pyrimidyl)tetrazole‐1‐acetic Acid

Reactions of Hpymtza [Hpymtza = 5‐(2‐pyrimidyl)tetrazole‐1‐acetic acid] with MnCl₂ · 4H₂O under different pH conditions, afforded the complexes [Mn(pymtza)₂(H₂O)₄] ( 1 ) and [Mn₂(pymtza)₂Cl₂(EtOH)] · H₂O ( 2 ). The compounds were structurally characterized by elemental analysis, IR spectroscopy and single‐crystal X‐ray diffraction. Compound 1 shows a mononuclear structure, whereas complex 2 has a 1D chain structure. In compound 1 , the pymtza ligand only acts in a monodentate manner to coordinate to one central Mn^II atom by one carboxylate atom, In 2 , pymtza acts as tetradentate ligand to connect three Mn^II ions. Compounds 1 and 2 display 3D networks by hydrogen bonding interactions. Furthermore, the luminescence properties of Hpymtza as well as compounds 1 and 2 were investigated at room temperature in the solid state.     

A d10 Metal Coordination Polymer Containing a Thiodiphthalic Ligand: Crystal Structure and Luminescent Property

A new two‐dimensional metal‐organic coordination polymer [Cd₂(2,3,2′,3′‐sdpa)(H₂O)₃] · 2H₂O ( 1 ) were hydro(solvo)thermally synthesized by the reaction of 2,3,2′,3′‐sulfonyldiphthalic acid (2,3,2′,3′‐H₄sdpa) with Cd(NO₃)₂ · 4H₂O and characterized by elemental analysis, thermogravimetry, IR and luminescence spectroscopy, and X‐ray diffraction. In complex 1 , two kinds of cadmium atoms are linked together by anionic sdpa^4– ligands to form a 2D metal‐organic network. The adjacent 2D layers further interact with each other through hydrogen bonds and π ··· π interactions to form a 3D supramolecular structure. The luminescence spectra and thermal properties of 1 were also investigated.     

2D LnIII(Nd/La)‐AgI Heterometallic and TmIII Homometallic Coordination Polymers Based on Pyridine Dicarboxylate ­Ligands

Two 2D 4d‐4f heterometallic coordination polymers, [LnAg(Py26DC)₂(H₂O)₃] · 3H₂O [Ln = Nd ( 1 ), La ( 2 ); H₂Py26DC = pyridine‐2,6‐dicarboxylic acid], and one 2D lanthanide homometallic coordination polymer, [Ln(Py25DC)(ox)_0.5(H₂O)₂] [Ln = Tm ( 3 ); H₂Py25DC = pyridine‐2,5‐dicarboxylic acid; ox = oxalate], were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single‐crystal X‐ray diffraction analysis. Both complexes 1 and 2 are isostructural and exhibit 3‐connected 2D heterometallic layer structures with the Schläfli symbol of (8² · 10), whereas complex 3 represents an extended 2D homometallic network structure with (4,4) topology.     

Synthesis,Characterization and Thermal Behavior of Two 4d‐4f Coordination Polymers Based on N and O Donor Ligands

Two new 4d‐4f coordination polymers, [Ag₂Nd(nic)₄(H₂O)₄·(ClO₄)·H₂O] ( 1 ) and [Ag₈Yb₄(inic)₈(ox)₆]· [Ag₂(inic)₂] ( 2 ) [nic = nicotinate, inic = isonicotinate and ox = oxalate] have been synthesized and characterized by element analysis, IR spectroscopy and thermal analysis, as well as single crystal X‐ray diffraction. Complex 1 exhibits a wavelike layer that is assembled from neodymium‐carboxylate subunits, silver centres and perchlorate ions. Complex 2 represents a extended heterometallic sandwich‐like layered network that is constructed from ytterbium‐oxalate layers and Ag(inic) chains.     

3D Coordination Polymers with Chiral Structures, [Ln2(tda)2(H2O)3]·5H2O: Hydrothermal Synthesis,Structural Characterization,and Luminescent Properties

Reactions of H₃tda (H₃tda = 1H‐1, 2, 3‐triazole‐4, 5‐dicarboxylic acid) with Sm(NO₃)₃ · 6H₂O, Eu(NO₃)₃ · 6H₂O, and Tb(NO₃)₃ · 6H₂O, in the presence of NaOH under hydrothermal conditions, produced three new coordination polymers, [Ln₂(tda)₂(H₂O)₃] · 5H₂O [Ln = Sm ( 1 ), Eu ( 2 ), Tb ( 3 )]. These compounds were structurally characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA), PXRD and single‐crystal X‐ray diffraction. The single‐crystal X‐ray diffraction studies of compounds 1 – 3 reveal that all compounds are three‐dimensional porous structures with chiral frameworks. Furthermore, the luminescence studies of compound 2 and 3 in the solid state reveal that they are potential luminescent materials at room temperature.     

Synthesis, Structural Characterization and Luminescence of Lanthanide Coordination Polymers with Pyridine-2,5-dicarboxylic Acid

The complexes of formulas [Ln₂(pydc)₂(Hpydc)₂(H₂O)₄]·2H₂O [Ln=Ce ( 1 ), Pr ( 2 ), H₂pydc=pyridine‐2,5‐di‐carboxylic acid] have been hydrothermally synthesized and characterized by elemental analysis, IR, TG and single‐crystal X‐ray diffraction. The structure analyses for 1 and 2 indicate that one‐dimensional metal helical chains are linked through carboxylate groups, and the helical chains are connected with the bridging pydc^2? anion, forming two‐dimensional layered polymeric structures. The luminescent properties of complexes were also discussed.     

基于二-吡嗪-(2, 3-f: 2′3′-h)-喹喔啉和吡啶-2，5-二羧酸混合配体的两个新奇金属有机超分子骨架的水热合成、晶体结构与光致发光

以二-吡嗪-(2, 3-f: 2′3′-h)-喹喔啉(Dpq)和吡啶-2,5-二羧酸(2,5-H2pda)两种混合配体与不同金属硝酸盐为原料,通过水热反应得到了两个新奇的金属有机骨架[Zn2(Dpq)2(2,5-pda)2(H2O)2]·2H2O(1)和[Cd2(Dpq)2(2,5-pda)2]·2H2O(2),并经元素分析、TG、IR、X-射线单晶衍射分析进行了表征。结构分析表明,2,5-pda采取不同的配位方式桥连金属离子分别形成了二聚物1和2D菱形网络2。在化合物1中,相邻的二聚物通过氢键和π-π堆积作用形成扭曲的a-Po超分子结构。在化合物2中,相邻的配位聚合物层通过氢键拓展成扭曲的a-Po超分子骨架,而π-π堆积起到巩固骨架的作用。化合物1和2的结构差异表明了金属离子和配体在配位聚合物自组装过程中对结构的影响。此外固态标题化合物在室温下表现出蓝色的发光性质。