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.     

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.     

Syntheses,characterizations, and redox behaviors of new self-assembled metal complexes with bridging ligands incorporating chalcogen sites

Three new complexes, [Zn(dbsf)₂(dmf)₂] · 5.5dmf (dbsf = 4,4′-sulfonyldibenzoate) (1β), [Cu(tdsa)(phen)₂] · 1.5EtOH (tdsa = 5,5′-thiodisalicylate, phen = 1,10-phenanthroline) (2), and [Cu(sdp)(phen) · Cu(Hsdp)(phen)(CH₃COO)] · 3EtOH (sdp = 4,4′-sulfonyldiphenolate) (3) were prepared and structurally characterized. Complex 1β shows a one-dimensional coordination framework constructed from bridges between Zn(II) centers with two ligands. Complex 2 is a monomeric complex, which assembles by π–π interactions. Complex 3 shows a unique two-dimensional coordination framework that is constructed from two Cu(II) centers, sdp, and Hsdp. The redox properties of these three complexes were characterized by solid-state cyclic voltammetry. Complexes 1β and 3 show irreversible reduction waves because of the reduction of their sulfone sites. Complex 2 shows an irreversible oxidation wave because of oxidation of the sulfide site.     

Synthesis,crystal structures and properties of two Pd(II) and Pt(II) complexes involving 3,5-diphenylpyrazole and NO2 donor ligands

A pyrazolate bridged binuclear Pd(II) complex [Pd₂(μ-dppz)₂(Hida)₂] · CH₃OH · 2H₂O (1) (dppz = 3,5-diphenylpyrazolate) with monoprotonated iminodiacetate (Hida) and a mononuclear Pt(II) complex containing Hdppz and 2,6-pyridinedicarboxylate (2,6-dipic) [Pt(Hdppz)(2,6-dipic)] · CH₃OH (2) have been synthesized and characterized by elemental analysis, ¹H NMR, ESI-MS and single crystal X-ray diffraction studies. The molecular packing for 1 shows a 2D network while that for 2 constitutes a left-handed 1D helix. Moderate luminescence property and antimicrobial activity against Bacillus subtilis have been noted for both.     

Two new isomeric complexes containing a well-resolved 1D water morph and (6, 3)-connected framework through hydrogen bonding interactions

Two new isomeric complexes, namely {[Cu(fum)(tpy)] · 5H₂O}_n (1) and [Cu₂(fum)₂(tpy)₂] · 4H₂O (2), have been synthesized simultaneously from the reaction of Cu(fum) with tpy (where fum = fumarate, tpy = 2,2′:6′,2″-terpyridine) under mild condition. The crystal structures of complexes were determined by X-ray single-crystal diffraction. Complex 1 stabilizes in an unusual 1D water tape notated T4(2)10(2), which is directed by two chiral helical water chains; binuclear complex 2 represents a complicated (6, 3)-connected framework via supramolecular interactions. Additionally, complex 1 exhibits weak ferromagnetic behavior.     

Diversity of carboxylate coordination in two novel zinc(II) cinnamate complexes

Two novel mixed-ligand zinc(II) complex compounds [Zn(cinn)₂(mpcm)]_n (1) and [Zn(p-HO-cinn)₂(nia)(H₂O)₂] · H₂O (2) (cinn = cinnamato, mpcm = methyl-3-pyridylcarbamate, nia = nicotinamide) were prepared and characterized by elemental analysis, infrared spectroscopy, single crystal X-ray diffraction and thermal analysis. Diverse modes of carboxylate coordination were found in the complexes. In 1 the cinnamate ligands coordinate as monodentate and bridging (syn–anti), respectively. The syn–anti carboxylate bridges connect the molecules of 1 to infinite polymeric helical chains. The structure of 2 is monomeric. One of the carboxylate oxygens of p-hydroxycinnamate is semi-coordinated (Zn–O = 2.549(2) Å).     

Multiple functions of amines in the synthesis of anionic,cationic, and neutral indium oxalates

Three new indium oxalates, formulated as H₃dpta·In(C₂O₄)(H₂O)₃·2SO₄ (1), In(qd)(C₂O₄)_1.5·1.5H₂O (2), and H₂bpp·In₂(C₂O₄)₄ (3) in which dpta = dipropylenetriamine, qd = quinoxaline-2,3(1H,4H)-dione, and bpp = 1,3-bis(4-piperidyl)propane, were prepared in the presence of different amines. These compounds have cationic, neutral, and anionic frameworks, respectively. Topological analyses reveal that compound 2 has an hcb net, while compound 3 has a dia net. The photoluminescent property of compound 2 was also investigated.     

Template-assisted self-assembly: Synthesis,structures, and magnetic properties of lanthanide(III)-cobalt(II) coordination complexes constructed with deprotonated 3,5-pyridinedicarboxylic acid ligand

Two new 3d-4f complexes, [LnCo(3,5-pdc)₂(3,5-Hpdc) (H₂O)₇]·H₂O (Ln = Gd 2, La 3; 3,5-pdcH₂ = pyridine-3,5-dicarboxylic acid), have been synthesized by the self-assembly of Ln(III) oxides, 3,5-pdcH₂ and the template molecule [Co(3,5-pdc)(H₂O)₅]·H₂O (1) under hydrothermal conditions. Heterometallic complexes 2 and 3 are isostructural with supracyclic units containing four Ln(III) ions and two Co(II) ions, in which Co(II) and Ln(III) are linked by the deprotonated 3,5-pdcH₂ ligands in three kinds of bridging modes. The weak antiferromagnetic coupling of complex 2 and 3 imply that the large 3,5-pdc bridges with the greater separation ( > 7 Å) cannot lead to long range magnetic ordering, the strength of d_n-f_n exchange coupling increasing with decreases the size of the lanthanide ion.     

Microporous metal–organic frameworks constructed by Cu(I)/Zn(II), Tpt and 1,4-benzenedicarboxylate

Two novel metal–organic frameworks, [Cu(tpt)(bdc)_1/2]_n · nH₂O (1) and [Zn(tpt)(bdc)_1/2I]_n (2) (tpt = 2,4,6-tris(4-pyridyl)-1,3,5-triazine, H₂bdc = 1,4-benzenedicarboxylic acid), have been prepared by hydrothermal reactions. In complex 1, Cu(I) center is in a trigonal coordination environment with bidentate tpt coordinating Cu(I) atoms to form 1D zigzag chains, and bdc ligand links the zigzag chains to form a 2D layered structure. In complex 2, Zn(II) center is in a trigonal–pyramidal environment with bidentate tpt coordinating Zn(II) atoms to form zigzag chains, and bdc links the zigzag chains to form metal–organic framework which contains interesting hexagonal nano-channels.     

Three cobalt (II) complexes with triethylenetetraaminehexaacetic acid: From binuclear complex to 3d-4f coordination polymers

The cobalt(II)–lanthanide(III) heteronuclear complexes [Ln(H₂O)₄Co₂(TTHA)(SCN)₂]·H₃O⁺ (H₆TTHA = triethylenetetraaminehexaacetic acid, Ln = La(2), Ce(3)) have been synthesized based on a binuclear building block of [Co₂(H₂TTHA)(H₂O)₂] in [Co₂(H₂TTHA)(H₂O)₂]·4H₂O (1). Single-crystal structures show that complex 1 is a binuclear complex, containing the [Co₂(H₂TTHA)(H₂O)₂] unit as a useful building block. Adding the La^3 + and Ce^3 + ions to this synthesis system, two new 3d-4f mixed complexes 2 and 3 were obtained. Complexes 2 and 3 show 3D framework, comprising an infinite 1D (one-dimensional) chain based on heterometallic Ln₂Co₂ (Ln = La(2), Ce(3)). Further investigations such as IR spectra, UV–vis spectra, TGA, XRD and magnetic properties were studied.     

New μ-oxo-bridged tetranuclear Cu(II) complex with Schiff-base ligand: Synthesis,crystal structure and magnetic properties

A new μ-oxo-bridged Cu(II) complex with cubane-like tetranuclear copper(II) complex, [Cu₄(L¹)₄] · 4H₂O (1) (H₂L¹ = 2-(3-methoxy-salicylidene-amino)-benzyl-alcohol), has been prepared, and structurally characterized by X-ray crystallography. Complex 1 crystallized in the monoclinic space group P₂₁/n and has a tetranuclear core of Cu₄O₄. The temperature dependence of magnetic susceptibility measurements shown that complex 1 exhibits a strong antiferromagnetic interaction with J = −103.4 cm⁻¹.     

Squarato-metal(II) complexes: Part 6. Synthesis,structure and magnetic characterization of an usual squarate-based 1D copper(II) coordination polymer composed of hexanuclear entities and a trinucleating ligand scaffold

The reaction of the polynucleating ligand 1,3,5-tris[bis(2-pyridylmethyl)aminomethyl]benzene (L^TDPA) with Cu(ClO₄)₂ · 6H₂O afforded the trinuclear complex [Cu₃(T^TDPA)(H₂O)₇](ClO₄)₆ · 5H₂O (1). When the reaction was performed in the presence of the squarate dianion, C₄O₄^2-, the compound {[Cu₆(L^TDPA)₂(μ_1,3-C₄O₄)₃](ClO₄)₆ · 12H₂O}_n (2) was obtained. Both compounds have been characterized by X-ray crystallography, showing a trinuclear and a 1D polymeric structures for 1 and 2, respectively. Complex 2 is composed of unusual hexametallic building blocks. Magnetic susceptibility measurements (SQUID) reveal essentially uncoupled copper(II) ions in complex 1, whereas complex 2 shows weak antiferromagnetic coupling via the squarato bridges within magnetically isolated dicopper(II) subunits of the 1D chain.     

Structural characterization of ferromagnetic bridged-acetato and -dichlorido copper(II) complexes based on bicompartmental 4-t-butylphenol

The reaction of Cu(II) salts with 2,6-bis[bis(2-pyridylmethyl)aminomethyl]-4-t-butylphenol (L^t-Bu-OH) afforded two bridged-phenoxido/hydroxido complexes. The dinuclear bridged acetate species [Cu₂(μ-L^t-Bu-O)(μ-CH₃COO)](PF₆)₂ (1) and the 1D polymeric doubly-bridged-chlorido {[Cu₂(μ-L^t-Bu-OH)(μ-Cl)₂](ClO₄)₂·4H₂O}_n (2). The two complexes were structurally characterized. Both complexes revealed ferromagnetic interactions; moderate in complex 1 (J = + 30.8 cm^− 1) and very weak (J = + 2.25 cm⁻¹) in 2.     

Three-dimensional fourfold interpenetrated (10, 3)-b nickel(II) framework with 5-(isonicotinamido)isophthalate

A new three-dimensional nickel(II) metal-organic framework [Ni(INAIP)(H₂O)₂]_n · nH₂O (1) [H₂INAIP = 5-(isonicotinamido)isophthalic acid] was synthesized under hydrothermal conditions, and characterized by single-crystal X-ray structure determination, thermogravimetric analysis, X-ray powder diffraction, IR and magnetic studies. The compound 1 has (10, 3)-b topology with not well known fourfold interpenetration, in which both Ni(II) atoms and INAIP^2? ligands act as three-connected nodes.     

Syntheses,crystal structures and luminescent investigations of cobalt(II) and zinc(II) complexes with 2-propyl-4,5-dicarboxylate-imidazole (H3PIDC)

Presented in this communication are four metal complexes based on 2-propyl-4,5-dicarboxylate-imidazole (H₃PIDC), including two Co(II) coordination compounds, [Co(H₂PIDC)₂(H₂O)₂] · 4H₂O (1) and 2[Co(H₂PIDC)₂(H₂O)₂] · 5H₂O (2), as well as two Zn(II) coordination compounds, [Zn(H₂PIDC)₂(H₂O)₂] · 4H₂O (3) and 2[Zn(H₂PIDC)₂(H₂O)₂] · 7H₂O (4). They contain the same coordinated unit of [M(H₂PIDC)₂(H₂O)₂] (M = Zn or Co). Interestingly, among these four complexes, 1 and 2, or 3 and 4 crystallized in different space group, which may be related with the number of the crystallized H₂O molecules.     

Polycatenated (4, 4) lanthanide(III) coordination networks based on apidate: Synthesis,structure and properties

Three rare earth coordination polymers, {[Ln₂(μ₃-ADI)₂(μ₂-ADI)(H₂O)₄]·H₂O}_n (Ln = Tb, 1; Eu, 2; Er, 3; ADI = adipate), which show the inclined interpenetration of (4, 4) nets and bright luminescence, were isolated from H₂PDC-assisted (H₂PDC = pyridine-2,3-dicarboxylatic acid) hydrothermal reactions of H₂ADI and Ln₂O₃.     

A 3D (3,8)-connected net based on the tetranuclear Cu4 units constructed from mixed organic ligands

Under hydrothermal conditions, a new polynuclear Cu(II) complex, [Cu₂(nip)(ina)(μ₃-OH)]₂·H₂O (1) (H₂nip = 5-nitroisophthalic acid, Hina = isonicotinic acid) has been synthesized with mixed organic ligands. Single crystal X-ray analysis reveals that complex 1 displays a three-dimensional (3D) structure based on the tetranuclear Cu₄ units. In the structure of 1, two pairs of symmetry-related Cu(II) ions are connected by six carboxyl and two μ₃-OH groups to generate the tetranuclear Cu₄ units, which are connected by the mixed ligands into a 3D framework. Topology analysis reveals a (3,8)-connected tfz-d net for 1. Magnetic studies display antiferromagnetic behavior for 1. And thermogravimetric analysis of 1 has also been investigated.     

Copper(II) and cadmium(II) complexes with an imide tethered imidazole and a copper(II) coordination polymer through ring opening reaction

The reactions of 2-(3-(1H-imidazol-1-yl)propyl)isoindoline-1,3-dione (L) with copper (II) chloride or copper(II) nitrate resulted in mononuclear complexes [CuL₄Cl₂]·12H₂O (1) or [CuL₄(H₂O)NO₃]NO₃·2H₂O (2) respectively; whereas the copper(II) acetate reacted with L to give a three dimensional coordination polymer {[Cu(L′)₂]·4H₂O}n (3), (where L′ = 2-(3-(1H-imidazol-1-yl)propylcarbamoyl)benzoate). The reaction of cadmium(II) acetate with L led to the formation of a seven-coordinated complex [CdL₃(O₂CCH₃)₂]·2H₂O (4).     

Structures and photoluminescence of coordination polymers assembled from bifunctional ligand containing both tetrazole and imidazole groups

Three new coordination polymers, namely, {[Cu₂(IPT)(SO₄)(OH)(H₂O)]·H₂O}_n (HIPT = 5-(4-(1H-imidazol-1-yl)phenyl)- 1H-tetrazolate, 1), {[Cd₂(IPT)(NPA)(OH)]·H₂O}_n (H₂NPA = 5-nitroisophthalic acid, 2), and {[Zn₂(IPT)(IDC)(H₂O)]·3H₂O}_n (H₃IDC = 1H-imidazole-4,5-dicarboxylic acid, 3), were assembled from a bifunctional organic ligand containing both tetrazole and imidazole groups with/without the aid of carboxylate coligands. Compound 1 possesses 2D structure built by 1D [Cu₂(IPT)(SO₄)(OH)]_n secondary building blocks and IPT⁻ linkers. The 2D networks are linked into 3D supramolecular framework via water chains in helical conformation. Compound 2 displays 3D pillar-layer framework with 2D layers based on tetranuclear Cd(II) SBUs and NPA^2 − pillars. Compound 3 exhibits a 3D framework constructed from the interconnection of 1D [Zn-IDC]_n chains and binuclear Zn₂(IPT)₂ rings. The thermal stabilities of porous compound 3 and luminescent properties of compounds 2 and 3 have also been studied in detail. They exhibit intense solid-state fluorescent emissions at room temperature.     

An unique trinuclear triply bridged Cu(II) compound containing double acetato and single azido bridges: Synthesis,X-ray structure and magnetism of [Cu3(dpyam)2(μ1,1-N3)2(μ-CH3COO- κ-O1)2(μ-CH3COO-κ-O1,O2)2] · 2(H2O) (dpyam = di-2-pyridylamine)

The synthesis, characterization, crystal structure and magnetic properties of the unique azido-acetato bridged trinuclear triply bridged Cu(II) compound, [Cu₃(dpyam)₂(μ_1,1-N₃)₂(μ-CH₃COO-κ-O¹)₂(μ-CH₃COO-κ-O¹,O²)₂] · 2(H₂O), is reported. In the centrosymmetric compound, the central Cu atom is linked to two terminal Cu atoms by a double acetato bridge and an azido bridge, thereby providing a linear trinuclear unit. The coordination geometry around each of the terminal Cu(II) ions is distorted square pyramidal, while the geometry of the central Cu(II) ion is elongated octahedral. The magnetic susceptibility measurements, measured from 5 to 300 K revealed a weak antiferromagnetic interaction between the Cu(II) ions with a J value of −10.2 cm⁻¹. In the EPR no signals for the low-lying doublet are resolved at 77 K.