Flexible bis(pyridyl-tetrazole) ligand-induced ring-containing metal–organic coordination polymers: synthesis,structures, and properties

Three coordination polymers (CPs), [Co(3-bptzp)(BDC)] (1), [Zn(3-bptzp)(BDC)] (2), and [Cd(3-bptzp)(BDC)] (3) (3-bptzp = 1,4-bis(5-(3-pyridyl)tetrazolyl)propane, H₂BDC = 1,3-benzenedicarboxylic acid), were synthesized under hydrothermal conditions. The CPs were structurally characterized by single-crystal X-ray diffraction, infrared spectroscopy (IR), elemental analyses, and powder X-ray diffraction (PXRD). Complexes 1–3 represent the first examples of CPs based on the flexible bis(pyridyl-tetrazole) 3-bptzp. Structure analyses reveal that 1–3 are 1-D ring-containing polymeric chains. For 2 and 3, adjacent 1-D chains are extended to 2-D supramolecular networks by hydrogen bonding. Dye adsorption properties of 1–3, electrochemical properties of 1, and fluorescent-sensing behaviors of 2 and 3 have also been investigated.     

Synthesis,structures and magnetic properties of two 2D → 3D entangled Cobalt(II) coordination polymers

Two Co(II) coordination polymers, namely Co(HBTC)(4-bpdb)·H₂O (1) and Co(HBTC)(3-bpdb)·H₂O (2) (H₃BTC = 1,3,5-benzenetricarboxylic acid, 4-bpdb = 1,4-bis-(4-pyridyl)-2,3-diaza-1,3-butadiene, 3-bpdb = 1,4-bis(3-pyridyl)-2,3-diaza-1,3- butadiene), have been hydrothermally synthesized and characterized both structurally and magnetically. Compound 1 exhibits a (2D → 3D) polythreaded architecture. It is assembled from HBTC^2? ligands to form a 2D puckered (4,4) layer plus 4-bpdb ligands which are orientated above and below each layer. The structure of compound 2 consists of a 2D (3,5) wavelike sheet constructed from HBTC^2? anions and 3-bpdb spacers. The uncoordinated carboxyl groups of the HBTC^2? ligands protrude from both sides of the wavelike sheet to form a 2D → 3D interdigitated motif. The magnetic properties of both compounds are also investigated, indicating antiferromagnetic interactions between the adjacent metal centers.     

Cluster-based networks: 1D and 2D coordination polymers based on {MnFe2(μ3-O)}-type clusters

A straightforward approach to heterometallic Mn-Fe cluster-based coordination polymers is presented. By employing a mixed-valent μ(3)-oxo trinuclear manganese(II/III) pivalate cluster, isolated as [Mn(II)Mn(III)(2)O(O(2)CCMe(3))(6)(hmta)(3)]·(solvent) (hmta = hexamethylenetetramine; solvent = n-propanol (1), toluene (2)) in the reaction with a μ(3)-oxo trinuclear iron(III) pivalate cluster compound, [Fe(3)O(O(2)CCMe(3))(6)(H(2)O)(3)]O(2)CCMe(3)·2Me(3)CCO(2)H, three new heterometallic {Mn(II)Fe(III)(2)} cluster-based coordination polymers were obtained: the one-dimensional polymer chain compounds {[MnFe(2)O(O(2)CCMe(3))(6)(hmta)(2)]·0.5MeCN}(n) (3) and {[MnFe(2)O(O(2)CCMe(3))(6)(hmta)(2)]·Me(3)CCO(2)H·(n-hexane)}(n) (4) and the two-dimensional layer compound {[MnFe(2)O(O(2)CCMe(3))(6)(hmta)(1.5)]·(toluene)}(n) (5). Single-crystal X-ray diffraction analysis reveals a μ(3)-oxo trinuclear pivalate cluster building block as the main constituent in all polymer compounds. Different M:hmta ratios in 1-5 are related to the different structural functions of the N-containing ligand. In clusters 1 and 2, three hmta ligands are monodentate, whereas in chains 3 and 4 two hmta ligands act as bridging ligands and one is a monodentate ligand; in 5, all hmta molecules act as bidentate bridges. Magnetic studies indicate dominant antiferromagnetic interactions between the metal centers in both homometallic {Mn(3)}-type clusters 1 and 2 and heterometallic {MnFe(2)}-type coordination polymers 3-5. Modeling of the magnetic susceptibility data to a isotropic model Hamiltonian yields least-squares fits for the following parameters: J(1)(Mn(II)-Mn(III)) = -6.6 cm(-1) and J(2)(Mn(III)-Mn(III)) = -5.4 cm(-1) for 1; J(1) = -5.5 cm(-1) and J(2)(Mn(III)-Mn(III)) = -3.9 cm(-1) for 2; J(1)(Mn(II)-Fe(III)) = -17.1 cm(-1) and J(2)(Fe(III)-Fe(III)) = -43.7 cm(-1) for 3; J(1) = -23.8 cm(-1) and J(2) = -53.4 cm(-1) for 4; J(1) = -13.3 cm(-1) and J(2) = -35.4 cm(-1) for 5. Intercluster coupling plays a significant role in all compounds 1-5.     

Syntheses,crystal structures,and luminescent properties of three metal coordination polymers based on adipic acid and 2-(pyridine-3-yl)-(1H)-benzimidazole

Three new metal coordination polymers constructed from adipic acid and 2-(pyridin-3-yl)-(1H)-benzimidazole ligands, [M(ADP)(3PBI)₂(H₂O)₂]·2H₂O (M = Ni and Co for 1 and 2, respectively) and [Cd(ADP)(3PBI)(H₂O)] (3) [ADP = adipic acid dianion; 3PBI = 2-(pyridin-3-yl)-(1H)-benzimidazole], have been synthesized by hydrothermal reactions and were characterized by X-ray single-crystal diffraction, elemental analyses, IR, powder X-ray diffraction, and thermogravimetry. Complexes 1 and 2 are isostructural. Both form a 1-D linear chain structure, which is further assembled into a 3-D supramolecular framework by π?π stacking and hydrogen bonding interactions. Complex 3 possesses a binuclear unit and displays a 2-D layer which is further extended to a 3-D supramolecular architecture via hydrogen bonding and other weak packing interactions. The luminescent properties of 3 were investigated in the solid state at room temperature.     

Two novel interpenetrated zinc(Ⅱ) and cadmium(Ⅱ) coordination polymers based on 4-imidazole-benzoate:Syntheses,crystal structures and properties

Two novel interpenetrated coordination polymers,[Zn(IBA)2]n (1) and {[Cd(IBA)2(H2O)].4H2O}n (2),have been synthesized by using 4-imidazole-benzoic acid (HIBA) as ligand under hydrothermal conditions. Complex 1 crystallizes in a chiral space group and has a two-fold interpenetrated 2D network structure with (4,4) topology,while complex 2 is a 3D porous dia network with four nets interpene-trating each other. The SHG activity of 1 and the photoluminescent property of 2 have been investigated.     

Three interpenetrated copper(Ⅱ) coordination polymers based on a V-shaped ligand:Synthesis,structures,sorption and magnetic properties

Three new CuⅡ coordination polymers,[Cu2(oba)2(H2O)(DMF)].3H2O(1),[Cu4(oba)4(DMF)4].4H2O.DMF(2) and [Cu2(oba)(hmp)2](3)(H2oba = 4,4'-oxybis(benzoic acid),Hhmp = 2-pyridine methanol,DMF = N,N'-dimethylformamide) were synthesized by solvothermal reactions and characterized by single-crystal X-ray diffraction.Both complexes 1 and 2 take three-dimensional(3D) three-fold interpenetrating PtS topology with 1D channels.In complex 3,Cu4 clusters were formed by the chelating hmp ligands,and then the clusters were fu...     

Adiabatic and non-adiabatic quantum dynamics calculation of O(1D) + D2 → OD + D reaction

Adiabatic (1A' or 1A' state) and non-adiabatic (2A'/1A' states) quantum dynamics calculations have been carried out for the title reaction (O((1)D) + D(2) → OD + D) to obtain the initial state-specified (v(i) = 0, j(i) = 0) integral cross section and rate constant using the potential energy surfaces of Dobbyn and Knowles. A total of 50 partial wave contributions have been calculated using the Chebyshev wave packet method with full Coriolis coupling to achieve convergence up to the collision energy of 0.28 eV. The total integral cross section and rate constant are in excellent agreement with experimental as well as quasi-classical trajectory results. Contributions from the adiabatic pathway of the 1A' state and the non-adiabatic pathway of the 2A'/1A' states, increase significantly with the collision energy. Compared to the O((1)D) + H(2) system, the kinetic isotope effect (k(D)/k(H)) is found to be nearly temperature independent above 100 K and its value of 0.77 ± 0.01 shows excellent agreement with the experimental result of 0.81.     

An unprecedented 2D → 3D metal-organic polyrotaxane framework constructed from cadmium and a flexible star-like ligand

An unprecedented 2D → 3D metal-organic polyrotaxane framework, based on a new star-like tri(4-imidazolylphenyl)amine ligand, has been synthesized and characterized, which represents the first example of 2D → 3D polyrotaxane entangled in a parallel fashion.     

Synthesis,structures and magnetic properties of four 3D heterometallic cobalt(II)–barium(II) coordination polymers

Four heterometallic complexes, namely {[CoBa(2,5-pdc)₂(H₂O)₃]_n·2nH₂O} (1), [CoBa(2,5-pdc)₂(H₂O)₄]_n (2), [CoBa(2,5-pdc)₂(H₂O)₅]_n (3) and [CoBa₂(2,5-pdc)₃(μ₂-H₂O)₂(H₂O)₄]_n (4) (2,5-H₂pdc?=?pyridine-2,5-dicarboxylic acid), have been hydrothermally synthesized and characterized both structurally and magnetically. All four complexes exhibit 3D frameworks, in which the Co(II) centers are chelated by pyridine nitrogen and carboxyl oxygen atoms in a five-membered ring. The Ba(II) centers are chelated and bridged by carboxyl oxygen atoms to extend the structures into 3D frameworks. The networks of the complexes can be controlled via rationally choosing the appropriate ligand and tuning the ratio of the two types of metal centers. The magnetic properties of complexes 1, 2 and 4 have been investigated from 2 to 300 K.     

Quantum-mechanical calculation of the reactions D + FH(ν = 0, 1, 2) → DF(ν′) + H and H + FD(ν = 0, 1, 2, 3) → HF(ν′) + D on a realistic potential energy surface

Collinear (two-mathematical-dimensional (2MD)) coupled-channel quantum-mechanical calculations have been performed on the reactions D + FH(ν = 0, 1, 2) → DF(ν′) + H and H + FD(ν = 0, 1, 2, 3) → HF(ν′) + D on a potential energy surface with a 40 kcal/mole barrier to exchange. This barrier height is close to that predicted by ab initio calculations and suggested by experiments. The relative effectiveness of reagent vibrational and translational excitation to promote reaction is considered. A one-mathematical-dimensional (1MD) model for these reactions is constructed and is shown to work very well for the D + FH reaction at high temperatures, and less well for that reaction at lower temperatures as well as for the reverse H + FD reaction. Possible reasons for the breakdowns of this model are discussed.     

A new family of magnetic 2D coordination polymers based on [MV(CN)8]3− (M=Mo,W) and pre-programmed Cu2+ centres

The self-assembly of [M(CN)₈]³⁻ (M=Mo, W) anion and polyamine complexes of Cu^II[Cu(tetren)]²⁺ and [Cu(dien)(H₂O)₂]²⁺ (tetren=tetraethylenepentamine, dien=diethylenetriamine) in acidic aqueous solution gives (tetrenH₅)_0.8{Cu^II ₄[W^V(CN)₈]₄}·7.2H₂O 1, (tetrenH₅)_0.8{Cu^II ₄[Mo^V(CN)₈]₄}·7.2H₂O 2, (dienH₃){Cu^II ₃[W^V(CN)₈]₃}·4H₂O 3 and (dienH₃){Cu^II ₃[Mo^V(CN)₈]₃}·4H₂O 4 2D coordination polymers. All compounds are structure-related: the crystal structures of isomorphous 1–2 and 3–4, respectively, consist of double-layered cyano-bridged {Cu^II[W^V(CN)₈]⁻}_n square grid backbones and non-coordinated fully protonated polyamine countercations as well as H₂O molecules located between the sheets. The magnetic measurements reveal long range ferromagnetic ordering with sharp phase transitions at T_C in range 28–37 K and coercivity in range 30–225 Oe at liquid helium temperature, T=4.3 K.     

Solvent-controlled structural variation from 1D+2D→3D network with coexistence of polycatenation and polythreading to the 2D→3D polythreaded array

This article represents two types of entanglements, [Co₂(bibp)(BTB)₂][Co(bibp)₂(H₂O)₂] (1) and [Co₃(bibp)₂(H₂O)₂(BTB)₂]·2H₂O·2DMF (2) (bibp = 4,4′-bis(1-imidazolyl)biphenyl and H₃BTB = 1,3,5-tris(4-carboxyphenyl)benzene), which are 2-D→3-D polycatenated frameworks formed by parallel catenation of 1-D+2-D→2-D polythreaded motifs based on the double-layered sheet penetrated by ribbons of rings (1) and a 2-D→3-D mutual polythreading of three double-layered sheets with dangling arms (2), which is assembled by the same initial materials by simply changing the volume ratio of water/DMF medium.     

Nano-dimensional square grid,helix chain,interpenetrated double layer,and chain of ring structures in new cobalt(II) metal–organic polymers based on 4,4′-oxybis-(benzoic acid) and 1,n-bis(imidazol-l-yl-methyl)benzene (n = 2, 3, 4)

Four cobalt(II) coordination polymers, [Co₂(oba)₂(1,2-bix)₂]_n (1), [Co(oba)(1,3-bix)]_n (2), {[Co₄(oba)₄(1,4-bix)₄]·6H₂O}_n (3), and {[Co₆(oba)₆(1,4-bix)₆]·2H₂oba·3DMF·11H₂O}_n (4), where H₂oba?=?4,4′-oxybis(benzoic acid), DMF = N,N-Dimethyl formamide, and 1,n-bix?=?1,n-bis(imidazol-l-yl-methyl)benzene (n?=?2, 3, 4), have been synthesized. These compounds were structurally characterized by single-crystal X-ray crystallography, IR spectroscopy, and thermogravimetric analysis. Compound 1 exhibits a 2-D nano square grid (4,4) network, while 2 features a 2-D structure with two distinct left- and right-handed helical chains. Compound 3 possesses a doubly interpenetrated double-layered framework structure. The structure of 4 is comprised of 1-D chains of rings. The structural differences reveal that the flexible dicarboxylate and neutral bis(imidazole) are effective building blocks in constructing coordination polymers with diverse architectures.     

Energy partitioning in O(1D2) reactions. I. O(D1D2) + H2S → OH(ν′) + HS

The complete vibrational distribution in the OH product of the reaction between O(¹D₂) and H₂S has been measured directly by the use of infrared emission spectroscopy under conditions appropriate to the stratospheric ozone layer. All energetically accessible vibrational levels are populated by the reaction. The vibrational distribution is inverted, having its maximum at OH(ν′ = 2 or 3). The reaction populating OH(ν′⩾1) partitions ≈ 44% of the available energy into OH vibration.     

Spectroscopic and extraction studies of new transition metal complexes with N,N ′- bis (2-aminothiophenol)-1, 4- bis (2-carboxaldehydephenoxy)butane

Metal complexes of La(III), Cu(II) and Ni(II) with a thio Schiff base derived from 1,4-bis(2-carboxaldehydephenoxy)butane and 2-aminothiophenol have been synthesized in absolute ethanol and characterized by microanalytical data, magnetic measurements, ¹H NMR, ¹³C NMR, UV-visible, IR-spectra, mass spectra and conductance measurements. The extractability of divalent cations was evaluated as a function of relationship between distribution ratios of the metal and pH or ligand concentration. The highest extraction percentage of Cu⁺² and Ni⁺² were at pH 7.0 and 6.4, respectively. The ligand can effectively be used in solvent extraction of copper(II) and nickel(II) from aqueous phase to organic phase.     

Capture and dissociation in the complex-forming CH(v = 0,1) + D2 → CHD + D, CD2 + H, CD + HD reactions and comparison with CH(v = 0,1) + H2

Rate coefficients for the CH(v = 0,1) + D(2) reaction have been determined for all possible channels (T: 200-1200 K), using the quasiclassical trajectory method and a suitable treatment of the zero point energy. Calculations have also been performed on the CH(v = 1) + H(2) reaction and the CH(v = 1) + D(2) → CH(v = 0) + D(2) process. Most of the results can be understood considering the key role played by the deep minimum of the potential energy surface (PES), the barrierless character of the PES, the energy of the reaction channels, and the kinematics. The good agreement found between theory and experiment for the rate coefficients of the capture process of CH(v = 0) + D(2), the total reactivity of CH(v = 1) + D(2), H(2), as well as the good agreement observed for the related CH(v = 0) + H(2) system (capture and abstraction), gives confidence on the theoretical rate coefficients obtained for the capture processes of CH(v = 1) + D(2), H(2), the individual reactive processes of CH(v = 1) + D(2), H(2), the abstraction and abstraction-exchange reactions for CH(v = 0) + D(2), and the inelastic process mentioned above, for which there are no experimental data available, and that can be useful in combustion chemistry and astrochemistry.     

Toward the self-assembly of metal-organic nanotubes using metal-metal and π-stacking interactions: bis(pyridylethynyl) silver(I) metallo-macrocycles and coordination polymers

Shape-persistent macrocycles and planar organometallic complexes are beginning to show considerable promise as building blocks for the self-assembly of a variety of supramolecular materials including nanofibers, nanowires, and liquid crystals. Here we report the synthesis and characterization of a family of planar di- and tri-silver(I) containing metallo-macrocycles designed to self-assemble into novel metal-organic nanotubes through a combination of π-stacking and metal-metal interactions. The silver(I) complexes have been fully characterized by elemental analysis, high resolution electrospray ionization mass spectrometry (HR-ESI-MS), IR, (1)H and (13)C NMR spectroscopy, and the solution data are consistent with the formation of the metallo-macrocycles. Four of the complexes have been structurally characterized using X-ray crystallography. However, only the di-silver(I) complex formed with 1,3-bis(pyridin-3-ylethynyl)benzene is found to maintain its macrocyclic structure in the solid state. The di-silver(I) shape-persistent macrocycle assembles into a nanoporous chicken-wire like structure, and ClO(4)(-) anions and disordered H(2)O molecules fill the pores. The silver(I) complexes of 2,6-bis(pyridin-3-ylethynyl)pyridine and 1,4-di(3-pyridyl)buta-1,3-diyne ring-open and crystallize as non-porous coordination polymers.     

Two coordination polymers based on 2,2′-biimidazoles and d10 metal ions: syntheses,structures, and luminescence

Two d¹⁰ metal coordination polymers, [Zn(µ-Me₂biim)Cl₂] _n (1) and [Cd₃(MeHbiim)₂(1,4-BDC)₃] _n (2) (Me₂biim?=?N,N′-dimethyl-2,2′-biimidazole, MeHbiim?=?N-methyl-2,2′-biimidazole, 1,4-BDC?=?1,4-benzenedicarboxylate), were synthesized under hydrothermal conditions and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, and single-crystal X-ray crystallography. Complex 1 features an infinite neutral zigzag 1-D chain. Interchain hydrogen-bonding interactions further extend the 1-D arrangement to generate a 2-D supramolecular architecture. Complex 2 features a 3-D coordination polymer with α-Po net topology, based on linear trinuclear {Cd₃O₁₄N₄} clusters. Both complexes have high thermal stability and exhibit strong luminescence at room temperature.     

Syntheses and characterization of two 1D Cu(II) coordination polymers with 2,2′:6′,2″-terpyridine ligand

The solution reactions of CuCl₂ with 2,2′:6′,2″-terpyridine (Terpy) and dicarboxylic acid (glutaric acid or suberic acid) afforded two 1D coordination polymers [Cu(Terpy)(C₅H₆O₄)] _n (I) and [Cu(Terpy)(C₈H₁₂O₄)] · 3H₂O (II) and their structures were characterized by IR, TG-DTA, and single-crystal X-ray diffraction. Crystallographic data for I: C₂₀H₁₆CuN₃O₄, M _r = 425.90, monoclinic, space group C2/c, a = 10.335(2), b = 21.193(4), c = 8.580(2) Å, β = 111.99(3)°, V = 1742.5(6) ų, Z = 4, ρ _c = 1.623 g/cm³, F(000) = 872, R = 0.0304 and wR = 0.0915; and those for II: C₂₃H₂₉CuN₃O₇, M _r = 523.03, triclinic, space group P \(\bar 1\), a = 8.362(2), b = 10.605(2), c = 14.617(3) Å, α = 73.26(3)°, β = 86.23(3)°, γ = 69.45(3)°, V = 1161.3(4) ų, Z = 2, ρ _c = 1.496 g/cm³, F(000) = 546, R = 0.0636 and wR = 0.1106. X-ray diffracion studies reveal that both complexes I and II feature 1D chain. The 1D polymer chains are connected by π-π-stacking interactions to generate 2D supramolecular layers.