Synthesis,Crystal Structure,Fluorescent and Antioxidation Properties of Cerium(III) and Europium(III) Complexes with Bis(3‐methoxysalicylidene)‐3‐oxapentane‐1,5‐diamine

Two aliphatic ether Schiff base lanthanide complexes (Ln = Eu, Ce) with bis(3‐methoxysalicylidene)‐3‐oxapentane‐1,5‐diamine (Bod), were synthesized and characterized by physicochemical and spectroscopic methods. [Eu(Bod)(NO₃)₃] ( 1 ) is a discrete mononuclear species and [Ce(Bod)(NO₃)₃DMF]_∞ ( 2 ) exhibits an inorganic coordination polymer. In the two complexes, the metal ions both are ten‐coordinated and the geometric structure around the Ln^III atom can be described as distorted hexadecahedron. Under excitation at room temperature, the red shift in the fluorescence band of the ligand in the complexes compared with that of the free ligand can be attributed to coordination of the rare earth ions to the ligand. Moreover, the antioxidant activities of the two complexes were investigated. The results demonstrated that the complexes have better scavenging activity than both the ligand and the usual antioxidants on the hydroxyl and superoxide radicals.     

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.     

Di­aqua­tris­(pentane‐2,4‐dionato‐O,O′)­holmium(III) mono­hydrate and di­aqua­tris­(pentane‐2,4‐dionato‐O,O′)holmium(III) 4‐hydroxy­pentan‐2‐one solvate dihydrate

The structures of the title compounds, [Ho(C₅H₇O₂)₃(H₂O)₂]·H₂O and [Ho(C₅H₇O₂)₃(H₂O)₂]·C₅H₈O₂·2H₂O, both show an eight‐coordinate holmium(III) ion in a square antiprismatic configuration. The packing of these structures consists of an infinite two‐dimensional network of hydrogen‐bonded mol­ecules. In both structures, the same hydrogen‐bonded chain of Ho^III complexes is found.     

Hydrothermal Syntheses,Crystal Structures,and Luminescent Properties of Three Organic‐Lanthanide Complexes with 3‐Hydroxycinnamic Acid

Three new homodinuclear lanthanide(III) complexes [Ln₂(L)₆(2,2′‐bipy)₂] [Ln = Tb^III ( 1 ), Sm^III ( 2 ), Eu^III ( 3 ); HL = 3‐hydroxycinnamic acid (3‐HCA); 2,2′‐bipy = 2,2′‐bipyridine] were synthesized and characterized by IR spectroscopy, elemental analyses, and X‐ray diffraction techniques. Complexes 1 – 3 crystallize in triclinic system, space group P$\bar{1}$ . In all complexes the lanthanide ions are nine‐coordinate by two nitrogen atoms from the 2,2′‐bipy ligand and seven oxygen atoms from one chelating L ligands and four bridging L ligands, forming distorted tricapped trigonal prismatic arrangements. The lanthanide(III) ions are intramolecularly bridged by eight carboxylate oxygen atoms forming dimeric complexes with Ln ··· Ln distances of 3.92747(15), 3.9664(6), and 3.9415(4) Å for complexes 1 – 3 , respectively. The luminescent properties in the solid state of HL ligand and Eu^III complex are also discussed.     

One‐dimensional Salen‐type Chain‐like Lanthanide(III) Coordination Polymers: Syntheses,Crystal Structures,and Fluorescence Properties

Four salen‐type lanthanide(III) coordination polymers [LnH₂L(NO₃)₃(MeOH)_x]_n [Ln = La ( 1 ), Ce ( 2 ), Sm ( 3 ), Gd ( 4 )] were prepared by reaction of Ln(NO₃)₃ · 6H₂O with H₂L [H₂L = N,N′‐bis(salicylidene)‐1,2‐cyclohexanediamine]. Single‐crystal X‐ray diffraction analysis revealed that H₂L effectively functions as a bridging ligand forming a series of 1D chain‐like polymers. The solid‐state fluorescence spectra of polymers 1 and 2 emit single ligand‐centered green fluorescence, whereas 3 exhibits typical red fluorescence of Sm^III ions. The lowest triplet level of ligand H₂L was calculated on the basis of the phosphorescence spectrum of Gd^III complex 4 . The energy transfer mechanisms in the lanthanide polymers were described and discussed.     

Two Oxime‐Based {LnIII3NiII3} Clusters with Triangular {Ln3(μ3‐Ο2)}7+ Core: Solvothermal Syntheses,Crystal Structures,and Magnetic Properties

Two isostructural heterometallic complexes, {[Dy₃Ni₃(H₂O)₃(mpko)₉(O₂)(NO₃)₃](ClO₄) · 3CH₃OH · 3CH₃CN} ( 1 ) and {[Gd₃Ni₃(H₂O)₃(mpko)₉(O₂)(NO₃)₃](NO₃) · 10.75CH₃OH} ( 2 ) [mpkoH = 1‐(pyrazin‐2‐yl)ethanone oxime], were solvothermally synthesized by varying lanthanide ions with different magnetic anisotropy. Structural analyses revealed that both complexes contain a peroxide anion‐aggregated triangular {Ln₃(μ₃‐Ο₂)}⁷⁺ core, which is surrounded by three Ni^II octahedra through threefold oxime linkages into a heterometallic hexanuclear cluster. Apparent antiferromagnetic interactions are observed between the adjacent spin carriers of 1 and 2 with the coupling constant J_{Ln ··· Ni} ≈ 12J_{Ln ··· Ln}. Additionally, 1 with highly anisotropic Dy^III site shows slow magnetization relaxation under zero dc field and 2 constructed from isotropic Gd^III ion displays significant cryogenic magnetocaloric effect with a maximum entropy change of 24.8 J · kg^–1 · K^–1 at 3.0 K and 70 kOe.     

Polymeric potassium di­aqua­hexa‐μ‐cyano‐holmium(III)­ruthenium(II) dihydrate

The crystal structure of the title bimetallic cyanide‐bridged complex, {K[HoRu(CN)₆(H₂O)₂]·2H₂O}_n, was determined by means of single‐crystal X‐ray diffraction techniques. The coordination about the central holmium(III) ion is eightfold in a square‐antiprismatic arrangement, while the ruthenium(II) ion is octahedrally coordinated. Channels permeating the crystal lattice contain the potassium cations and two zeolitic water mol­ecules. The Ho^III and K atoms lie at sites with mm symmetry and the Ru atom is at a site with 2/m symmetry.     

Syntheses,Structures, and Photoluminescence Properties of a Series of 3D Zn‐Ln Heterometallic Complexes with 2,3‐Pyrazine Dicarboxylic Acid as a Bridging Ligand

A series of 3D d–f heterometallic coordination polymers, {[Ln₂Zn(Pzdc)₄(H₂O)₆] · 2H₂O}_n [Ln = La ( 1 ), Pr ( 2 ), Nd ( 3 ), Sm ( 4 ), Eu ( 5 ), Gd ( 6 ), Tb ( 7 ), Dy ( 8 )] (H₂Pzdc = 2,3‐pyrazine dicarboxylic acid), were synthesized by one‐pot reactions under hydrothermal conditions. X‐ray crystallographical analysis and powder X‐ray diffraction analysis reveal that the complexes 1 – 8 are isostructural and adopt a multi‐parallel quadrilateral channel network structure with {4.6 · 2}₂{4 · 2.6 · 2.8 · 2}{6 · 3}2{6 · 5.8}₂ topology, in which the central Ln^III ion is nine‐coordinate by four oxygen atoms and two nitrogen atoms from four ligands and three oxygen atoms from three coordinated H₂O molecules and the central Zn^II ion is six‐coordinate by four oxygen atoms and two nitrogen atoms from four ligands. Moreover, the photophysical properties related to the electronic transition for complexes 4 , 5 , 7 , and 8 were investigated by the excitation and emission spectra as well as the emission lifetimes.     

Synthesis,Crystal Structures,and Photoluminescence of Lanthanide Coordination Polymers with 4‐Acetamidobenzoate

The reactions of Ln(NO₃)₃ · 6H₂O and 4‐acetamidobenzoic acid (Haba) with 4,4′‐bipyridine (4,4′‐bpy) in ethanol solution resulted in three new lanthanide coordination polymers, namely {[Ln(aba)₃(H₂O)₂] · 0.5(4,4′‐bpy) · 2H₂O}_∞ [Ln = Sm ( 1 ), Gd ( 2 ), and Er ( 3 ), aba = 4‐acetamidobenzoate]. Compounds 1 – 3 are isomorphous and have one‐dimensional chains bridged by four aba anions. 4,4′‐Bipyridine molecules don’t take part in the coordination with Ln^III ions and occur in the lattice as guest molecules. Moreover, the adjacent 1D chains in the complex are further linked through numerous N–H ··· O and O–H ··· O hydrogen bonds to form a 3D supramolecular network. In addition, complex 1 in the solid state shows characteristic emission in the visible region at room temperature.     

Three Ternary Rare Earth(III) Complexes Based on 3‐[(4,6‐Dimethyl‐2‐pyrimidinyl)thio]‐propanoic Acid and 1,10‐Phenanthroline: Synthesis,Crystal Structure and Antioxidant Activity

Three ternary rare earth [Nd^III ( 1 ), Sm^III ( 2 ) and Y^III ( 3 )] complexes based on 3‐[(4,6‐dimethyl‐2‐pyrimidinyl)thio]‐propanoic acid (HL) and 1,10‐phenanthroline (Phen) were synthesized and characterized by IR and UV/Vis spectroscopy, TGA, and single‐crystal X‐ray diffraction. The crystal structures showed that complexes 1 – 3 contain dinuclear rare earth units bridged by four propionate groups and are of general formula [REL₃(Phen)]₂ · nH₂O (for 1 and 2 : n = 2; for 3 : n = 0). All rare earth ions are nine‐coordinate with distorted mono‐capped square antiprismatic coordination polyhedra. Complex 1 crystallizes in the monoclinic system, space group P2₁/c with a = 16.241(7) Å, b = 16.095(7) Å, c = 19.169(6) Å, β = 121.48(2)°. Complex 2 crystallizes in the monoclinic system, space group P2₁/c with a = 16.187(5) Å, b = 16.045(4) Å, c = 19.001(4) Å, β = 120.956(18)°. Complex 3 crystallizes in the triclinic system, space group P1 with a = 11.390(6) Å, b = 13.636(6) Å, c = 15.958(7) Å, α = 72.310(17)°, β = 77.548(15)°, γ = 78.288(16)°. The antioxidant activity test shows that all complexes own higher antioxidant activity than free ligands.     

N,N′‐Bis(Salicylidene)‐1,2‐Cyclohexanediamine Lanthanide(III) Coordination Polymers: Syntheses,Crystal Structures,and Luminescence Properties

The salen‐type ligand H₂L [H₂L = N,N′‐bis(salicylidene)‐1,2‐cyclohexanediamine] was utilized for the synthesis of two lanthanide(III) coordination polymers [LnH₂L(NO₃)₃MeOH]_n [Ln = Eu ( 1 ) and Ln = Lu ( 2 )]. The single‐crystal X‐ray diffraction analyses of 1 and 2 revealed that they are isomorphous and exhibit one‐dimension neutral structure, in which H₂L effectively functions as a bridging ligand and give rise to a chain‐like polymer. The luminescent properties of polymers in solid state and in solution were investigated and 1 exhibits typical red luminescence of Eu^III ions in solid state and dichloromethane solution and 2 emits the ligand‐centered blue luminescence. The energy transfer mechanisms in these luminescent lanthanide polymers were described through calculation of the lowest triplet level of ligand H₂L.     

Three Phenoxo‐Bridged Dinuclear Lanthanide Complexes: Syntheses,Crystal Structures,and Magnetic Properties

Three dinuclear lanthanide complexes [Ln₂(H₂L)₂(NO₃)₄] [Ln = Dy ( 1 ), Tb ( 2 ), and Gd ( 3 )] [H₃L = 2‐hydroxyimino‐N′‐[(2‐hydroxy‐3‐methoxyphenyl)methylidene]‐propanohydrazone] were solvothermally synthesized by varying differently anisotropic rare earth ions. Single‐crystal structural analyses demonstrate that all the three complexes are crystallographically isostructural with two centrosymmetric Ln^III ions aggregated by a pair of monodeprotonated H₂L^– anions. Weak intramolecular antiferromagnetic interactions with different strength were mediated by a pair of phenoxo bridges due to superexchange and/or single‐ion anisotropy. Additionally, the Dy^III‐based entity shows the strongest anisotropy exhibits field‐induced single‐molecule magnetic behavior with two thermally activated relaxation processes. In contrast, 3 with isotropic Gd^III ion has a significant cryogenic magnetocaloric effect with the maximum entropy change of 25.7 J · kg^–1 · K^–1 at 2.0 K and 70.0 kOe.     

Syntheses,Crystal Structures,and Properties of Three Copper(II) Complexes Constructed by 4‐(4,6‐Bis(1H‐pyrazol‐1‐yl)‐1,3,5‐triazin‐2‐yl)morpholine

Three copper(II) complexes of the polydentate N‐donor ligand [4‐(4,6‐bis(1H‐pyrazol‐1‐yl)‐1,3,5‐triazin‐2‐yl)morpholine] (L) with chlorides, nitrates, and perchlorates as anions, namely, [CuCl₂(L)] · 0.5(MeCN) ( 1 ), [Cu(NO₃)₂(H₂O)(L)] · (MeCN) ( 2 ), and [Cu(L)₂](ClO₄)₂ · (MeCN) ( 3 ) were synthesized and structurally characterized by IR, elemental analysis and X‐ray crystallographic analysis. In these complexes, the L ligand binds the copper(II) cation in the tridentate N₃ form. The coordination arrangement around the central copper(II) atom is distorted square‐pyramidal in 1 but it is distorted octahedral in 2 and 3 . The interesting noncovalent interactions such as hydrogen bonds, π–π stacking, and anion–π interactions present in the solid‐state structures are discussed. The crystal results reveal that the counteranions play important roles in determining the diverse structures of these complexes. Moreover, the PXRD, TG, DRS, and fluorescence properties of compounds 1 – 3 were investigated.     

Syntheses,Structures, and Photoluminescence of Lanthanide Coordination Polymers Based on 4‐Oxo‐1,4‐dihydro‐2,6‐pyridinedicarboxylic acid

Investigating the coordination chemistry of H₂CDA (4‐oxo‐1,4‐dihydro‐2,6‐pyridinedicarboxylic acid) with rare earth salts Ln(NO₃)₃ under hydrothermal conditions, structure transformation phenomenon was observed. The ligand, H₂CDA charged to its position isomer, enol type structure, H₃CAM (4‐hydroxypyridine‐2,6‐dicarboxylic acid). Six new lanthanide(III) coordination polymers with the formulas [Ln(CAM)(H₂O)₃]_n [Ln = La ( 1 ), Pr, ( 2 )] and {[Ln(CAM)(H₂O)₃] · H₂O}_n [Ln = Nd, ( 3 ), Sm, ( 4 ), Eu, ( 5 ), Y, ( 6 )] were synthesized and characterized. The X‐ray structure analyses show two kinds of coordination structures. The complexes 1 and 2 and 3 – 6 are isostructural. Complexes 1 and 2 crystallize in the monoclinic C₂/c space group, whereas 3 – 6 crystallize in the monoclinic system with space group P2₁/n. In the two kinds of structures, H₃CAM displays two different coordination modes. The Sm^III and Eu^III complexes exhibit the corresponding characteristic luminescence in the visible region at an excitation of 376 nm.     

The Building Block [FeIII(pzphen)(CN)4]– and its Lanthanide Complexes: Synthesis,Crystal Structure,and Magnetic Properties

The cyanide building block [Fe^III(pzphen)(CN)₄]^– and its four lanthanide complexes [{Fe^III(pzphen)(CN)₄}₂Ln^III(H₂O)₅(DMF)₃] · (NO₃) · 2(H₂O) · (CH₃CN) [Ln = Nd ( 1 ), Sm ( 2 ), DMF = dimethyl formamide] and [{Fe^III(pzphen)(CN)₄}₂Ln^III(NO₃)(H₂O)₂(DMF)₂](CH₃CN) [Ln = Gd ( 3 ), Dy ( 4 )] were synthesized and structurally characterized by single‐crystal X‐ray diffraction. Compounds 1 and 2 are ionic salts with two [Fe^III(pzphen)(CN)₄]^– cations and one Ln^III ion, but compounds 3 and 4 are cyano‐bridged Fe^III‐Ln^III heterometallic 3d‐4f complexes exhibiting a trinuclear structure in the same conditions. Magnetic studies show that compound 3 is antiferromagnetic between the central Fe^III and Gd^III atoms. Furthermore, the trinuclear cyano‐bridged Fe^III₂Dy^III compound 4 displays no single‐molecular magnets (SMMs) behavior by the alternating current magnetic susceptibility measurements.     

A Novel Self‐assembled Nickel(II)‐Cerium(III) Heterotetranuclear Dimer Constructed from N2O2‐type Bisoxime and Terephthalic Acid: Synthesis,Structure, and Photophysical Properties

By self‐assembly of a Salamo‐type ligand H₂L [H₂L = 1,2‐bis(3‐methoxysalicylideneaminooxy)ethane] with Ni(OAc)₂ · 4H₂O, Ce(NO₃)₃ · 6H₂O, and H₂bdc (H₂bdc = terephthalic acid), a novel Ni^II‐Ce^III heterometallic complex, [{Ni(L)Ce(NO₃)₂(CH₃OH)(DMF)}₂(bdc)], was obtained. Two crystallographically equivalent [Ni(L)Ce(NO₃)₂(CH₃OH)(DMF)] moieties lie in the inversion center, and are linked by one bdc^2– ligand leading to a heterotetranuclear dimer, in which the carboxylato group bridges the Ni^II and Ce^III atoms. Moreover, the photophysical properties of the Ni^II‐Ce^III complex were studied.     

Structure and cytotoxicity of zinc (II) and cobalt (II) complexes based on 1,3,5‐tris(1‐imidazolyl) benzene

Three novel complexes, [Zn (tib)₂·(H₂O)₂]·(NO₃)₂ ( 1 ), [Co (tib)₂]·2NO₃ ( 2 ) and [Co₂(tib)₂(btc)]·H₂O ( 3 ) [H₄btc = 1,2,4,5‐benzenetetracarboxylic acid; H₂tib = 1,3,5‐tris(1‐imidazolyl)benzene], were synthesized and characterized by single‐crystal X‐ray, IR and elemental analysis. The interaction of these complexes with FS‐DNA (fish sperm DNA) was monitored, and binding constants were determined using UV/Vis, which revealed that they have the ability to bind to FS‐DNA. DNA‐binding constants (K) for the three complexes were 2.2 × 10⁴ m ^?1, 0.7 × 10⁴ m ^?1 and 0.09 × 10⁴ m ^?1, respectively. The interaction capacity of the complexes with FS‐DNA has been investigated by fluorescence spectroscopy. Stern–Volmer quenching plot values for complexes 1 , 2 and 3 were 0.3784, 0.1028 and 0.076, respectively. The viscosity measurement suggested that complexes 1 , 2 and 3 interact with DNA in an intercalation mode. In addition, anti‐cancer activities of these complexes investigated through MTT assays in vitro indicated that the complexes showed good cytotoxic activity against cancer cell lines. Cytotoxic activity of test complexes against two different cancer cell lines (HeLa and KB cells) showed significant cancer cell inhibition rates. Flow cytometry experiments and morphological apoptosis studies showed that the complexes induced apoptosis of HeLa tumor cell lines. Finally, a further molecular docking technique was employed to confirm the binding of the complexes toward the molecular target DNA.     

Hydrothermal Syntheses,Crystal Structures and Properties of Two Novel 3‐D Lanthanide(III) Coordination Polymers Constructed with Mixed Heterocyclic Carboxylic Acid

The hydrothermal reactions of Ln₂O₃ (Ln = Nd and Eu) with pyridine‐2,5‐dicarboxylic acid (H₂pydc) resulted in the formation of two isomorphic three‐dimensional (3D) polymeric Ln^III complexes, [Ln(pydc)(nic)·H₂O]_n (Ln = Nd( 1 ) and Eu( 2 )), in which nic (nicotinate; also named as pyridine‐2‐carboxylic acid) might have been formed from the pydc ligands through the C–C bond cleavage and CO₂ molecules releasing. Pydc ligands bridge lanthanide centers to form the three‐dimensional framework featuring hexagonal channels along the axis a which are occupied by bridging nic anions and mono‐coordinated water molecules. From the topological point of view, two three‐dimensional nets are binodal with six‐ and three‐connected nodes, which display a distorted rutile (4.6²)₂(4²·6¹⁰·8³) topology. Magnetic measurements (2‐300 K) reveal that all polymers possess weak antiferromagnetic property. A strong fluorescence emission spectrum of compound 2 was observed.     

Synthesis,Structure, and Magnetic Properties of a Series of Dinuclear Lanthanide Complexes Assembled by Acetate and a Schiff Base Ligand

Five dinuclear lanthanide complexes [Ln₂L₂(NO₃)₂(OAc)₄] · 2CH₃CN [Ln = Gd ( 1 ), Tb ( 2 ), Dy ( 3 ), Ho ( 4 ), and Er ( 5 )] [L = 2‐((2‐pyridinylmethylene)hydrazine)ethanol] were synthesized from the reactions of Ln(NO₃)₃ · 6H₂O with L and CH₃COOH in the presence of triethylamine. Their crystal structures were determined. They show similar dinuclear cores with the two lanthanide ions bridged by four acetate ligands in the μ₂‐η¹:η² and μ₂‐η¹:η¹ bridging modes. Each Ln^III ion in complexes 1 – 5 is further chelated by one L ligand and one nitrate ion, leading to the formation of a nine‐coordinated mono‐capped square antiprism arrangement. The dinuclear molecules in 1 – 5 are consolidated by hydrogen bonds and π ··· π stacking interactions to build a two‐dimensional sheet. Their magnetic properties were investigated. It revealed antiferromagnetic interactions between the Gd^III ions in 1 and ferromagnetic interactions between the Tb^III ions in 2 . The profiles of χ_mT vs. T curves of 3 – 5 reveal that the magnetic properties of 3 – 5 are probably dominated by the thermal depopulation of the Stark sublevels of Ln^III ions.     

Two 3d‐4f Heterometallic Coordination Polymers of Macrocyclic Oxamide with Benzotriazole‐5‐carboxylate Co‐ligand: Syntheses,Crystal Structures and Magnetic Properties

Two heterometallic 3d–4f coordination polymers, [Gd(CuL)₂(Hbtca)(btca)(H₂O)] · 2H₂O ( 1 ) and [Er(CuL)₂(Hbtca)(btca)(H₂O)] · H₂O · CH₃OH ( 2 ) (CuL, H₂L = 2,3‐dioxo‐5,6,14,15‐dibenzo‐1,4,8,12‐tetraazacyclo‐pentadeca‐7,13‐dien; H₂btca = benzotriazole‐5‐carboxylic acid) were synthesized by solvothermal methods and characterized by single‐crystal X‐ray diffraction. Complexes 1 and 2 exhibit a double‐strand meso‐helical chain structures formed by [Ln^IIICu^II₂] (Ln^III = Gd, Er) units by oxamide and benzotriazole‐5‐carboxylate bridges. They are isomorphic except that one free water molecule of 1 is replaced by a methanol molecule. All 1D chains are further interlinked by hydrogen bonds resulting in a 3D supramolecular architecture. The magnetic properties of the compound 1 and 2 are also discussed.