Self-assembly of a novel 3D copper(I)-tetrazolate supramolecular framework via interpenetration of porous 2D double-layer motifs

The self-assembly of CuCN and 1H-TAZ ligand under hydrothermal conditions generated a novel three-dimensional hybrid supramolecular framework, namely, [Cu₆(TAZ)₄(CN)₂]_n (1) (TAZ = tetrazole). Single-crystal X-ray diffraction show that [Cu₂(TAZ)₂] binuclear subunits are linked by μ₂- and μ₃-CN groups to give a 2D double-wave-shaped network, which possesses 1D channels with four open-windows. The 2D bilayers interpenetrated each other to form the 3D supramolecular framework of 1.     

Syntheses,structures and luminescence of three copper(I) cyanide coordination polymers incorporating flexible N-donor ligands

Three copper(I) cyanide coordination polymers, namely [Cu₈(CN)₈(btmb)₂]_n (1), [Cu(CN)(btmb)_0.5]_n (2) and [Cu₂(CN)₂(dpa)]_n (3) (btmb = 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene, dpa = di(4-pyridyl)amine), were synthesized under hydrothermal conditions and characterized by elemental analyses, IR spectra, PXRD and thermogravimetric analyses. Single-crystal X-ray diffraction analyses reveal that complex 1 is an interesting 2D double-layered network constructing from eight distinct Cu(I) centers, eight μ₂-cyanides and two tetradentate cis-btmb ligands. Complex 2 is a ladder-like coordination polymer assembled by CuCN linear chain and bidentate trans-btmb linker. Complex 3 has a 2D wave-like network constructing from CuCN zigzag chain and V-shape dpa spacer. These coordination polymers are thermally stable up to 270–300 °C. They emit blue luminescence originating from ligand-centered emission.     

Synthesis,crystal structure and magnetic properties of a new cyanide-bridged mixed-valence copper(I)/copper(II) clathrate

A unique cyanide-bridge mixed-valence Cu^I/Cu^II clathrate of formula [Cu^I₂(CN)₃][{Cu^II(tren)}₂(μ-CN)](CF₃SO₃)₂ [tren = tris(2-aminoethyl)amine] containing cyanide-bridged [{Cu^II(tren)}₂(μ-CN)]^3 + binuclear cations stacked between anionic honeycomb layered copper(I) cyanide networks, was synthesized and structurally characterized by single crystal X-ray diffraction. Variable-temperature magnetic susceptibility studies showed that the cyanide bridge mediates a strong antiferromagnetic interaction between the copper(II) centers (J = − 160 cm^− 1, the spin Hamiltonian being defined as H = −J S_A⋅S_B).     

Two new 2D organic–inorganic hybrids assembled by lanthanide-substituted polyoxotungstate dimers and copper–complex linkers

Two new organic–inorganic hybrid copper–lanthanide heterometallic polyoxometalates (POMs), [Cu(dap)₂]_3.5[Cu(dap)₂(H₂O)]₃[La(α-SiW₁₁O₃₉)₂]·5H₂O (1) and H[Cu(dap)₂(H₂O)][Cu(dap)₂]₄[Eu(α-PW₁₁O₃₉)₂]·13H₂O (2) (dap = 1,2-diaminopropane), have been made under hydrothermal conditions and characterized by elemental analyses, IR spectra, XRD, thermogravimetric (TG) analyses and X-ray single-crystal diffraction. They both display interesting 2D organic-inorganic hybrid POMs containing 3d-4f cations and organic dap ligands. To the best of knowledge, 1 represents the first 2D Cu–Ln heterometallic silicotungstate assembled by [La(α-SiW₁₁O₃₉)₂]^13 − dimers and [Cu(dap)₂]^2 + linkers, while 2 is a new 2D Cu-Eu heterometallic Keggin-type phosphotungstate with dap ligands. Furthermore, the variable-temperature magnetic susceptibility of 2 has been investigated.     

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.     

Dicyanamido–metal(II) complexes. Part 3: Hydrolysis of the dicyanamide into amidocyanamide during its interaction with Cu(II) perchlorate and 2-pyridylcarbonyl-N,N-bis(2-pyridylmethyl)amine

The reaction of Cu(ClO₄)₂, 2-pyridylcarbonyl-N,N-bis(2-pyridylmethyl)amine (DPA-CO-py) and sodium dicyanamide (Nadca) in aqueous medium led to the isolation of three complexes: {[Cu(DPA)(μ_1,5-dca)]ClO₄}_n (1), [Cu₂(pic)₂(μ_1,3-H₂NCO–N–CN)₂(H₂O)₂] · 2H₂O (2) and Cu(pic)₂ · H₂O (3). The Cu²⁺ ion, during its complex formation with DPA-CO-py and dca not only assisted the hydrolysis of DPA-CO-py to the corresponding di(2-methylpyridyl)amine (DPA) and picolinic acid (Hpic) but also resulted in partial hydrolysis of one of the two nitrile groups of the dicyanamide, NC–N–CN^? (dca) to amidocynamide, H₂NCO–NH–CN. The complexes were structurally characterized and the single X-ray structures for 1 and 2 reveal their identity. Complex 1 forms a 1D polymeric chain with the dca acting as a μ_1,5-bridging ligand via the terminal nitrile nitrogen atoms. A distorted SP geometry around the Cu²⁺ centers was achieved by the three N-atoms of the DPA and by the two nitrile groups of the bridging dca ligands. Complex 2 consists of a dimeric unit with CuN₃O₂ chromophore in coordination polyhedron that has a distorted SP geometry. The amidocyanamide ion, H₂NCO–N–CN^? acts as bis(monodentate) μ_1,3-bridging ligand via the central amido and terminal nitrile nitrogen atoms whereas the picolinate anion forms a six-membered chelate ring through its pyridyl nitrogen and an oxygen atom of the carboxylate group, and the aqua water occupies the apical position of the structure. Complex 1 exhibits very weak antiferromagnetic coupling (J = ?0.31 cm^?1) whereas 2 shows a significant antiferromagnetic interaction between the two copper centers (J = ?13.6 cm^?1).     

A cyanide-bridged two-dimensional grid-like FeIII–CoII complex based on the pentacyanideferrite(III) building block

A cyanide-bridged Fe^III–Co^II heterometallic complex {[Fe(1-CH₃im)(CN)₅][Co(H₂O)₂]}n·3H₂O (1-CH₃im = 1-methylimadazole) (2) has been synthesized by the reaction of Co^II(ClO₄)₂·6H₂O with the pentacyanideferrite(III) building block (Ph₄P)₂[Fe^III(1-CH₃im)(CN)₅]·4.5H₂O (1). X-Ray single crystal diffraction analysis shows that complex 2 has a two-dimensional (2D) grid-like structure. Magnetic investigations show that complex 2 displays long-range antiferromagnetic ordering with T_N = 9.45 K. The typical metamagnetic behaviors were observed with the critical field of ca. 4000 Oe at 1.82 K.     

Hydrothermal synthesis,crystal structure and strong blue fluorescence of a novel 3D coordination polymer containing copper and zinc centers linked by isonicotinic acid ligands

The first mixed metal Zn/Cu coordination polymer, [Zn₃Cu₂(IN)₈] (1) (HIN = isonicotinic acid) was synthesized under hydrothermal conditions. The three dimensional structure of 1 has a novel topological metal-organic framework, which is built up by Zn²⁺, Cu⁺ and ligands IN to generate an open-framework with an unusual helical [–Zn(Cu)-IN–]_n chains along the b axis. The very strong blue fluorescence for 1 can be observed in the solid state.     

A new Cu-based metal-organic framework built upon infinite 1D rod-shaped secondary building units

A new Cu(II) metal-organic framework {[Cu_1.5(1,3-bdc)(dtb)(OH)(H₂O)](H₂O)}_n (1) (1,3-H₂bdc = 1,3-benzenedicarboxylic acid, dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene), has been synthesized and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analysis, and IR spectra. Compound 1 features a 3-D open framework constructed by infinite 1D rod-shaped [Cu₃(OH)₂]_n chains as secondary building units. The magnetic property of the complex has also been investigated.     

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.     

Two Mn(II)–Au(I) supramolecular assemblies bonded by coordination,aurophilicity and hydrogen-bonding, π–π interactions and their magnetic properties

Two Mn(II)–Au(I) supramolecular assemblies {{Mn[Au(CN)₂]₂(H₂O)₄} [Au(CN)₂]₂(H₂bpy) · H₂O}(bpy = 4,4′-bipyridine) 1 and {Mn(4,4′-dmbpy) [Au(CN)₂]₂(CH₃OH)} (4,4′-dmbpy = 4,4′-dimethyl-bipyridine) 2 have been synthesized and magnetic properties have been investigated The interplay of aurophilicity, coordination, hydrogen-bonding and π–π interactions in two complexes result in three-dimensional network.     

Role of spacers and substituents in the self-assembly process: Syntheses and characterization of two novel thiocyanatocuprates polymers

Two novel cation-induced complexes, {(Phen-dq) [Cu₂(SCN)₄]}_n (1) and {(Phen-dzp) [Cu₂(SCN)₄]}_n (2) [Phen-dq = (C₁₄H₁₂N₂)²⁺, 5,6-dihydropyrazino[1, 2, 3, 4-lmn]-1, 10-phenanthrolinium, Phen-dzp = (C₁₅H₁₄N₂)²⁺, 6,7-dihydro-5H-[1, 4]diazepino[1, 2, 3, 4-lmn][1,10]phenanthroline-4, 8-diium], have been synthesized via the self-assembly reaction in solution. The compound 1 possesses a two-dimensional supramolecular network linked by bridging thiocyanate groups. Complex 2 is also a two-dimensional polymeric architecture with the organic cation Phen-dzp trapped in it. Each Cu(I) atom is coordinated by two N atoms and two S atoms from four NCS groups to form a Cu₂(NCS)₂ rectangular dimer unit. In these two compounds, thanks to the difference from organic cations, the simple modification from Phen-dq to Phen-dzp leads to distinct structures between 1 and 2, and these “planar” cations are effective guests to manipulate the aggregate structure of thiocyanatocuprates.     

Three 3D Cu(II) coordination polymers constructed from 1,2,4,5-benzenetetracarboxylate acid and three positional isomeric ligands

Based on 1,2,4,5-benzenetetracarboxylate acid (H₄btc), and mixed with three isomeric dipyridyl ligands, three novel 3D Cu(II) coordination polymers [Cu₂(btc)(4,4′-bpt)]·2H₂O (1) [4,4′-bpt = 1H-3,5-bis(4-pyridyl)-1,2,4-triazole], [Cu(btc)_0.5(3,4′-bpt)]·0.5H₂O (2) [3,4′-bpt = 1H-3-(3-pyridyl)-5-(4-pyridyl)-1,2,4- triazole] and [Cu(btc)_0.5(3,3′-bpt)]·2H₂O (3) [3,3′-bpt = 1H-3,5-bis(3-pyridyl)-1,2,4-triazole] have been synthesized and characterized, respectively. 1 is a 3D pillared double-layer complex containing a novel bilayer unit; 2 is a 3D pillared-layer architecture with (4,4)-sql layer; 3 exhibits a 3D structure containing 3D [Cu(btc)]_∞ motif and 1D [Cu(bpt)]_∞ chain. The topological analysis shows that 1 can be simplified to a (4,6)-connected network with the Schläfli symbol of (4²·6⁴)₂(4⁸·6⁷), 2 a (4,6)-connected network with the symbol of (4⁴·6²)(4⁴·6¹⁰·8), and 3 a four-connected topology with the symbol of (3²·10³·11)₂(3²·10⁴).     

Three 1D copper(I/II) complexes of 4,6-dipyridyl-2-aminopyrimidine: Effect of the ligand isomerism on the structural motif

Three copper(I/II) complexes [Cu₂(HL1)₂Cl]_n (1), [Cu(H₂L2)Cl]_n (2), and [Cu₂(H₂L3)Cl₂]_n (3) were synthesized by the reaction of CuCl₂ · 2H₂O with three isomers of 4,6-dipyridyl-2-aminopyrimidine: H₂L1, H₂L2, and H₂L3 under hydrothermal conditions. Although in compounds 1–3, the three ligands all exhibit bridging coordination modes, the structures of the resultant 1D polymers are very different. This result indicates that the structural motif of compounds 1–3 could be directed by the ligand isomers.     

Hydrothermal syntheses,crystal structures and photocatalytic properties of three POM-templated organic–inorganic hybrid compounds

Three new POM-templated organic–inorganic compounds, Cu₂(3,5-bptp)₂[H₂SiW₁₂O₄₀]·4H₂O (1), Ag₂(3,5-bptp)₂[HPW₁₂O₄₀]·4H₂O (2), [Cu₄(OH)₃Cl(H₂O)₃(4-bpo)₃](SiW₁₂O₄₀)·5H₂O (3) (3,5-bptp = 3,5-bis(3-(pyrid-4-yl)-1,2,4-triazolyl)-pyridine, 4-bpo = 2,5-bis(4-pyridyl)-1,3,4-oxadiazole) were hydrothermally synthesized and characterized by elemental analysis and single crystal X-ray diffraction. Crystal structural analysis indicates that compounds 1 and 2 are isostructural and show one dimensional zigzag chains with [H₂SiW₁₂O₄₀]^2 − as guest molecules. Compound 3 is two dimensional sheets constructed from [Cu₄(OH)₃Cl(H₂O)₃] clusters and 4-bpo ligands with [SiW₁₂O₄₀]^4 − as guest molecules. Furthermore, the photocatalytic degradation of methyl orange (MO) with 3 was studied under visible light irradiation, indicating excellent photocatalytic activity.     

A 3D K–Cu heterometal–organic coordination polymer with luminescent properties constructed from two kinds of Cu-cyanide complex units and binuclear K oxo-cluster

A novel 3D heterometal–organic coordination polymer [{K₂(H₂O)₆} {Cu₃(Hpimdc)₂(CN)₂}{Cu₂(H₃pimdc)₂(CN)}]·2H₂O (1) (H₃pimdc = 2-propyl-1H-imidazole-4,5-dicarboxylic acid) has been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, PXRD, UV–vis, and single-crystal X-ray diffraction. In complex 1, adjacent K⁺ ions are linked through H₃pimdc to form binuclear chain units {K₂(H₂O)₆}_n, which connect with unique Cu-cyanide complex linker {Cu₃(CN)₂(Hpimdc)₂} to form 2D layers. The 2D layers are further connected via another linkage unit {Cu₂(CN)(H₃pimdc)₂} to form 3D frameworks with (4¹16²)₂(3³4²5¹10¹12³16⁴) topology. The H₃pimdc ligand in 1 exhibits μ₂- and μ₄-two kinds of coordination fashions. In addition, the N₂ adsorption, fluorescence, and photocatalytic properties of polymer 1 are evaluated detailed.     

A tetranuclear pyrophosphate-bridged Cu(II) complex with 4,4′-bipyridine and 1,10-phenanthroline: Synthesis,structural, and magnetic properties

A new tetranuclear pyrophosphate-bridged Cu(II) complex with 4,4′-bipyridine and 1,10-phenanthroline [Cu₄(phen)₄(bpy)₂(P₂O₇)₂]·10H₂O (1) has been hydrothermal synthesized and characterized by single-crystal X-ray analysis, element analysis, IR spectroscopy, TG analysis, and UV–vis spectra. Variable-temperature magnetic susceptibility measurements show the occurrence of antiferromagnetic interactions between the neighbor Cu(II) centers in 1. The analysis of the magnetic data in the whole temperature range allows the determination of the value of the intramolecular magnetic coupling (J = − 13.16 cm^− 1).     

Synthesis and mechanism study of a dimeric tetranuclear carbonate-bridged copper(II) complex resulting from CO2 fixation by controlling O2 concentration

A dimeric tetranuclear carbonate-bridged Cu(II) complex [Cu₄(DPA-ⁱBu)₄(μ₂-CO₃)₂(MeOH)₂]^4 + 1 was prepared in-situ through oxidation of Cu(I) species by controlling the concentration of O₂ in CO₂. Lower concentration of O₂ led to the formation of 1 after CO₂ fixation but higher would give product as bis-μ₂-hydroxo complex [Cu(DPA-ⁱBu)(OH)]₂^2 + 2, which was found to be an intermediate to generate trinuclear carbonated complex [Cu₃(DPA-ⁱBu)₃(μ₃-CO₃)(MeCN)₂(H₂O)]^4 + 3. The mechanism of this reaction was proposed and the nucleophilic attack of μ-peroxo Cu(II) species to CO₂ molecules was suggested to be responsible for the generation of 1.     

Conformational isomerism of a flexible fluorinated bis-pyridinecarboxamide ligand in the structural direction of two distinct layered CuII coordination polymers

Reaction of a flexible pyridinecarboxamide ligand N,N′-[(2,3,5,6-tetrafluoro-1,4-phenylene) bis(methylene)]bis(pyridine-4-carboxamide) (H₂tfpbbp) with Cu^II chloride or perchlorate affords two coordination polymers {[Cu(H₂tfpbbp)(tfpbbp)(H₂O)] · 2DMF · 4H₂O}_n (1) and {[Cu(H₂tfpbbp)₂(ClO₄)₂] · 3H₂O}_n (2). Both complexes have 2-D (4,4) layered networks extended by the exo-bidentate bridging ligands, which however consist of distinct [Cu–ligand]₄ meshes owing to the conformational difference of ligands. Their spectroscopic, thermal, and fluorescence properties have also been investigated.     

Synthesis,structure and magnetic properties of a copper molybdate hybrid inorganic/organic solid with a novel 10-connected three-dimensional network topology

Hydrothermal reaction of CuCl₂, MoO₃, and 4,4′-dipyridylketone (4,4′-dpk) afforded green crystals of the mixed metal oxide phase {[Cu₂(MoO₄)₂(4,4′-dpk)(H₂O)]·H₂O}_n (1). According to single-crystal X-ray diffraction, {Cu₂O₂} dimers link into 1-D {Cu₂O₂(μ-H₂O)}_n chains via bridging aqua ligands. These chains form [Cu₂(MoO₄)₂(H₂O)]_n slabs via linkage through tetrahedral molybdate anions. In turn, the copper molybdate slabs are pillared through tethering 4,4′-dpk ligands into a 10-connected three-dimensional lattice with an unprecedented 3¹²4³⁰5²6 topology. Variable temperature magnetic data above 140 K were fit to the Curie–Weiss law, with C = 0.17 cm³ K/mol Cu and Θ = 70 K, indicating likely ferromagnetic coupling within the dinuclear kernels of 1; low temperature data points towards the possibility of interdimer antiferromagnetic interactions.