Five New Zinc Phosphite Structures: Tertiary Building Blocks in the Construction of Hybrid Materials

Studies on the Genesis and Proton Conductivity of Imidazole-Based Linear and Open-Framework Zinc Phosphites

Three new zinc phosphites, [HIm]₂[Zn₃(HPO₃)₄] (1), [Zn₂(HPO₃)₂Im₂] (2), and [Zn(HPO₃)Im] (3) (Im = imidazole), have been synthesized from the hydro/solvothermal reaction of zinc acetate, dimethyl phosphite, and imidazole by varying the temperature and solvent of the reaction medium. The structure of 1 is built from vertex-sharing of four HPO₃-capped Zn₃P₃ units and adopts an open framework with 12-ring channels stabilized by HIm cations via N-H···O hydrogen bonds. For 2, the inorganic skeleton is comprised of alternating ZnO₄ and HPO₃ tetrahedra, while the coordinatively associated ZnN₂O₂ fragments occupy the 12-ring hexagonal channels. Compound 3 adopts a ladder-type one-dimensional structure and exhibits N-H···O hydrogen-bonding interactions to afford a supramolecular assembly. A plausible rationale on the genesis of 1-3 has been put forth by reacting the preformed inorganic zinc phosphites Zn{OP(O)(OMe)H}₂ or [Zn₂(HPO₃)₂(H₂O)₄]·H₂O with imidazole as the structure-directing ligand. Alternating-current impedance measurements reveal that 1 and 3 exhibit proton conductivities on the order of 10^-3-10^-4 S cm^-1 between 25 and 100 °C under 35 and 77% relative humidity in repeated impedance cycles (E_a = 0.22-0.35 eV). On the contrary, the conduction property is completely impaired in 2 under similar conditions.

Two new inorganic–organic hybrid zinc phosphites and their derived ZnO/ZnS heterostructure for efficient photocatalytic hydrogen production

Two novel inorganic–organic hybrid zinc phosphites, namely, [Zn(1,2-bimb)_0.5(HPO₃)]_n (1) and [Zn(1,4-bmimb)_0.5(HPO₃)]_n (2), (1,2-bimb = 1,2-bis(imidazol-1ylmethyl)benzene; 1,4-bmimb = 1,4-bis((2-methyl-1H-imidazol-1yl)methyl)benzene) were synthesized for the first time by hydrothermal reaction. Compound 1 generates a three-dimensional (3D) pillared-layer structure with a 2-nodal 3,4-connected 3,4T15 topology. While compound 2 exhibits a 2D hybrid zinc phosphite sheet with a 3,4-connected 3,4L83 topology network. Utilizing compound 1 and compound 2 as templates and Na₂S as an etching agent, a series of highly efficient ZnO/ZnS photocatalysts were obtained. The optimized 1-160 sample demonstrates the highest evolution rate of 22.6 mmol g⁻¹ h⁻¹, exceeding the rate of commercial ZnS samples by more than 14.5 times. The remarkable photocatalytic activity should be attributed to the unique heterojunction structure which shortens the free path of charge carriers and enhances the charge separation efficiency. This work provides a facile strategy for preparing photocatalysts with efficient photocatalytic hydrogen production derived from inorganic–organic hybrid material.

Though a solvo-thermal synthesis process, two novel inorganic–organic hybrid zinc phosphite were constructed. Using these hybrid zinc phosphite as template, the ZnO/ZnS heterostructures were prepared by a sulfuration method for enhanced photocatalytic performance.

Crystal structure of poly[μ2-1,4-bis((1H-imidazol-1-yl)methyl)benzene-κ2 N:N′)-(μ2-4-sulfidobenzoate-κ2 O:S)cobalt(II)] dihydrate, C42H44Co2N8O7S2

C42H44Co2N8O7S2, monoclinic, P21 (no. 4), a = 7.3941(6) Å, b = 15.3043(14) Å, c = 9.7831(7) Å, β = 101.315(7)°, V = 1085.56(15) Å3, Z = 1, R gt(F) = 0.0392, wR ref(F 2) = 0.0749, T = 293(2) K.

Template or ligand? Different structural behaviours of aromatic amines in combination with zinco-phosphite networks

The solution-mediated syntheses and crystal structures of catena-poly[bis-(2-amino-3-hy-droxy-pyridinium) [zinc-di-μ-phospho-nato] dihydrate], {(C5H7N2O)[Zn(HPO3)2]·2H2O} n , (I), and poly[(benzene-1,2-di-amine)(μ5-phospho-nato)zinc], [Zn(HPO3)(C6H8N2)] n , (II) are described. The extended structure of (I) features [010] anionic chains of vertex-sharing ZnO4 tetra-hedra and HPO3 pseudopyramids; these chains are characterized by disorder over major [occupancy 0.7962 (13)] and minor [0.2038 (13)] components, which can be superimposed on each other by a nominal translational shift. The 2-amino-3-hy-droxy-pyridinium cations and water mol-ecules of crystallization inter-act with the ZnPO chains by way of numerous O-H⋯O and N-H⋯O hydrogen bonds. The structure of (II) features a direct Zn-N bond to the neutral 1,2-di-amino-benzene species as part of ZnO3N tetra-hedra as well as HPO3 pseudopyramids. The Zn- and P-centred groupings are linked through their O-atom vertices into infinite (010) sheets and the structure is consolidated by N-H⋯O hydrogen bonds and N-H⋯π inter-actions. The crystal of (I) chosen for data collection was found to be an inversion twin in a 0.56 (2):0.44 (2) domain ratio.

Coordination polymers built from 1,4-bis(imidazol-1-ylmethyl)benzene: from crystalline to amorphous

A review of the different crystalline and amorphous coordination polymers (CPs) built from 1,4-bis(imidazol-1-ylmethyl)benzene (bix) is presented, with special emphasis on the large variety of structures reported so far and their potential applications.

Mixed-ligand coordination of the (UO2)2+ cation and apophyllite topology of uranyl chlorochromate layer in the structure of ((CH3)2CHNH3)[(UO2)(CrO4)Cl(H2O)]

Addition of the Cl-0 anions to the synthesis mixture stabilizes specific structures of uranyl complexes which results in new compounds with the unprecedented structural topologies. ((CH3)2CHNH3)[(UO2)(CrO4) · Cl(H2O)]is a new member of the small family of compounds based upon the Ur(Xm O n )5 (X = Cl, Br, I) bipyramids. The structure is based upon uranyl chloride chromate layers that alternate with the layers of protonated amine molecules. The layers contain UrClO4 pentagonal bipyramids that share three of its equatorial corners with CrO4 tetrahedra. Topological analysis shows that the [(UO2)(CrO4)Cl(H2O)]-0 layer belongs to the same topology of interpolyhedral linkage as in α-UO2MoO4(H2O)2. This type of topology (linkage of 4-membered rings creating 8-membered rings) is known in silicate crystal chemistry as the topology of the [Si4O10] layers in the minerals of the apophyllite group. Their linkage via various intermediate units results in a large family of open-framework and pillared silicates.

Poly[[μ(2)-1,3-bis-(imidazol-1-ylmeth-yl)benzene][μ(2)-2,2'-dihy-droxy-1,1'-methyl-enebis(naphthalene-3-carboxyl-ato)]zinc]

In the title compound, [Zn(C₂₃H₁₄O₆)(C₁₄H₁₄N₄)]_n, the Zn^II ion is four-coordinated in a distorted tetra­hedral geometry. The 1,3-bis­(imidazol-1-ylmeth­yl)benzene and 2,2′-dihy­droxy-1,1′-methyl­enebis(naphthalene-3-carboxy­l­ate) ligands con­nect the Zn^II ions alternately in different directions, forming a layered structure parallel to the ac plane. Topological analysis reveals that the whole structure is a (4,4) network. The layers are further assembled into a three-dimensional supra­molecular structure via C—H⋯O and C—H⋯π inter­actions.

Hexa-kis-(1-benzyl-1H-imidazole-κN)manganese(II) bis-(perchlorate)

In the title compound, [Mn(C₁₀H₁₀N₂)₆](ClO₄)₂, the Mn^II ion, located on an inversion center, is coordinated by six N atoms from three pairs of symmetry-related 1-benzyl-1H-imidazole ligands in a distorted octa­hedral geometry. In the crystal, weak inter­molecular C—H⋯O hydrogen bonds link the complex cations and perchlorate anions.

An ice-like water hexamer with 3 symmetry in the hydrogen-bonded structure of 2,3,5,6-tetrafluoro-1,4-bis(imidazol-1-ylmethyl)benzene dihydrate

An ice-like hexameric water cluster, stabilized by the flexible bis-imidazolyl compound 2,3,5,6-tetrafluoro-1,4-bis(imidazol-1-ylmethyl)benzene (Fbix), is found in the trigonal R3 crystal structure of the title compound, C(14)H(10)F(4)N(4).2H(2)O or Fbix.2H(2)O. The Fbix molecule lies about an inversion centre with one water molecule in the asymmetric unit in a general position. A cyclic chair-like hexameric water cluster with 3 symmetry is generated with a hydrogen-bonded O...O distance within the hexamer of 2.786 (3) A. The Fbix molecule adopts a trans conformation, where the imidazole ring makes a dihedral angle of 70.24 (11) degrees with the central tetrafluorinated aromatic ring. Each water hexamer is connected by six Fbix molecules through intermolecular O-H...N hydrogen bonds [N...O = 2.868 (3) A] to yield a three-dimensional supramolecular network with primitive cubic (pcu) topology. Large voids in each single pcu network lead to fourfold interpenetrated aggregates of Fbix.2H(2)O.

Oxyfluorotitanophosphate cluster [Ti10P4O16F44]16-: synthesis and characterization of K16[Ti10P4O16F44]

One oxyfluorotitanophosphate cluster compound, K16[Ti10P4O16F44], has been synthesized and structurally characterized. As far as we know, it is the first cluster compound for titanophosphate.

Amine-controlled assembly of metal-sulfite architecture from 1D chains to 3D framework

Whereas open-framework materials have been made in a variety of chemical compositions, few are known in which 3-connected SO3(2)- anions serve as basic building units. Here, we report four new metal-sulfite polymeric structures, (ZnSO3)Py (1, py = pyridine), (ZnSO3)2(2,2'-bipy)H2O (2, 2,2'-bipy = 2,2'-bipyridine), (ZnSO3)2(TMDPy) (3, TMDPy = 4,4'-trimethylenedipyridine), and (MnSO3)2en (4, en = ethylenediamine) that have been synthesized hydrothermally and structurally characterized. In these compounds, low-dimensional 1D and 2D inorganic subunits are assembled into higher 2D or 3D covalent frameworks by organic ligands. In addition to the structure-directing effect of organic ligands, the flexible coordination chemistry of Zn2+ and SO3(2)- also contributes to the observed structural diversity. In compounds 1-3, Zn2+ sites alternate with trigonal pyramidal SO3(2)- anions to form three types of [ZnSO3]n chains, whereas in compound 4, a 2D-corrugated [MnSO3]n layer is present. Compound 1 features a rail-like chain with pendant pyridine rings. The pi-pi interaction between 2,2'-bipy ligands is found between adjacent chains in compound 2, resulting in 2D sheets that are further stacked through interlayer hydrogen bonds. Compound 3 exhibits a very interesting inorganic [(ZnSO3)2]n chain constructed from two chairlike subunits, and such chains are bridged by TMDPy ligands into a 2D sheet. In compound 4, side-by-side helical chains permeate through 2D-corrugated [MnSO3]n layers, which are pillared by neutral ethylenediamine molecules into a 3D framework that can be topologically represented as a (3,6)-connected net. The results presented here illustrate the rich structural chemistry of metal-sulfites and the potential of sulfite anions as a unique structural building block for the construction of novel open-framework materials, in particular, those containing polymeric inorganic subunits that may have interesting physical properties such as low-dimensional magnetism or electronic properties.

Syntheses and Characterization of Six Coordination Polymers of Zinc(II) and Cobalt(II) with 1,3,5-Benzenetricarboxylate Anion and Bis(imidazole) Ligands

Six new coordination polymers, namely [Zn1.5(BTC)(L1)(H2O)2].1.5H2O (1), [Zn3(BTC)2(L2)3] (2), [Zn3(BTC)2(L3)1.5(H2O)].H2O (3), [Co6(BTC)4(L1)6(H2O)3].9H2O (4), [Co1.5(BTC)(L2)1.5].0.25H2O (5), and [Co4(BTC)2(L3)2(OH)2(H2O)].4.5H2O (6), where L1 = 1,2-bis(imidazol-1-ylmethyl)benzene, L2 = 1,3-bis(imidazol-1-ylmethyl)benzene, L3 = 1,1'-(1,4-butanediyl)bis(imidazole), and BTC = 1,3,5-benzenetricarboxylate anion, were synthesized under hydrothermal conditions. In 1-6, each of L1-L3 serves as a bidentate bridging ligand. In 1, BTC anions act as tridentate ligands, and compound 1 shows a 2D polymeric structure which consists of 2-fold interpenetrating (6, 3) networks. In compound 2, BTC anions coordinate to zinc cations as tridentate ligands to form a net with (64.82)2(86)(62.8)2 topology. In compound 3, BTC anions act as tetradentate ligands and coordinate to zinc cations to form a net with (4.62.83)2(8.102)(4.6.83.10)2 topology. In compound 5, each BTC anion coordinates to three Co cations, and the framework of 5 can be simplified as (64.82)2(62.82.102)(63)2 topology. For 4 and 6, the 2D cobalt-BTC layers are linked by bis(imidazole) ligands to form 3D frameworks. In 6, the Co centers are connected by micro3-OH and carboxylate O atoms to form two kinds of cobalt-oxygen clusters. Thermogravimetric analyses (TGA) for these compounds are discussed. The luminescent properties for 1-3 and magnetic properties for 4-6 are also discussed in detail.

Syntheses, Structures, and Magnetic Properties of Inorganic−Organic Hybrid Cobalt(II) Phosphites Containing Bifunctional Ligands

Seven new cobalt(II) phosphites, [Co(HPO(3))(C(14)H(14)N(4))(H(2)O)(2)].2H(2)O (1), [Co(HPO(3))(C(22)H(18)N(4))].H(2)O (2), [Co(2)(HPO(3))(2)(C(22)H(18)N(4))(2)H(2)O].H(2)O (3), [Co(2)(HPO(3))(2)(C(12)H(10)N(4))(1.5)H(2)O].1.5H(2)O (4), [Co(HPO(3))(C(14)H(14)N(4))(0.5)].H(2)O (5), [Co(HPO(3))(C(18)H(16)N(4))(0.5)] (6), and [Co(HPO(3))(C(18)H(16)N(4))(0.5)] (7) were synthesized in the presence of 1,2-bis(imidazol-1-ylmethyl)benzene (L1), 1,4-bis(benzimidazol-1-ylmethyl)benzene (L2), 1,3-bis(benzimidazol-1-ylmethyl)benzene (L3), 1,4-bis(1-imidazolyl)benzene (L4), 1,4-bis(imidazol-1-ylmethyl)benzene (L5), 1,4-bis(imidazol-1-ylmethyl)naphthalene (L6), and 1,5-bis(imidazol-1-ylmethyl)naphthalene (L7), respectively, and their structures were determined by X-ray crystallography. Compound 1 is a molecular compound in which two cobalt(II) ions are held together by double mu-O linkages. The inorganic framework of compounds 2 and 3 are composed of vertex-shared CoO(2)N(2)/CoO(3)N(2) and HPO(3) polyhedra that form four rings; these are further linked by an organic ligand to generate 2D sheets. Compounds 4 and 5 both have 1D inorganic structures, with the bifunctional ligands connected to each side of the ladder by coordination bonds to give 2D hybrid sheets. A 3D organically pillared hybrid framework is observed in 6 and 7. In 6, the stacking of the interlayer pillars gives rise to a small hydrophobic channel that extends through the entire structure parallel to the sheets. The temperature-dependent magnetic susceptibility measurements of these compounds show weak interactions between the metal centers, mediated through the mu-O and/or O-P-O linkages.