A New Lattice Inclusion Host Involving Double-stranded Columns of Diol Molecules [1]

Abstract

Crystallization of dialcohol 4 from benzene yields an inclusion compound whose crystal structure [(C₁₃H₂₄O₂)₂·(C₆H₆), P2₁/c, a 7.918(2), b 13.505(2), c 14.924(5) Å, β 109.30(1)°, Z 2, R 0.069] shows that the host molecules are present as parallel doubly-stranded columns. Each column is constructed from one strand of (+)-, and a second of (-)-, enantiomers of 4. These two chirally pure strands are linked through a continuous chain of hydrogen bonding …O—H…O—H…O—H… to complete the column, and the benzene guests occupy interstitial sites between the parallel columns.     

4‐Iodo­anilinium 3‐nitro­phthalate(1–): tripartite sheets built from O—H...O and N—H...O hydrogen bonds

In the title compound, 4‐iodoanilinium 2‐carboxy‐6‐nitrobenzoate, C₆H₇IN⁺·C₈H₄NO₆⁻, the anions are linked by an O—H...O hydrogen bond [H...O = 1.78 Å, O...O = 2.614 (3) Å and O—H...O = 171°] into C(7) chains, and these chains are linked by two two‐centre N—H...O hydrogen bonds [H...O = 1.86 and 1.92 Å, N...O = 2.700 (3) and 2.786 (3) Å, and N—H...O = 153 and 158°] and one three‐centre N—H...(O)₂ hydrogen bond [H...O = 2.02 and 2.41 Å, N...O = 2.896 (3) and 2.789 (3) Å, N—H...O = 162 and 105°, and O...H...O = 92°], thus forming sheets con­taining R(6), R(8), R(13) and R(18) rings.     

meso‐5,5,7,12,12,14‐Hexamethyl‐1,4‐diaza‐8,11‐diazoniacyclotetradecane bis(2‐naphthoate) ethanol disolvate: centrosymmetric five‐component aggregates linked into sheets by C—H⃛π(arene) hydrogen bonding

The title compound is an ethanol‐solvated salt, C₁₆H₃₈N₄²⁺·2C₁₁H₇O₂⁻·2C₂H₆O, in which the cation lies across a centre of inversion in P2₁/c. The ions are linked by N—H⃛O hydrogen bonds [H⃛O = 1.70 and 2.30 Å, N⃛O = 2.624 (2) and 3.136 (2) Å, and N—H⃛O = 178 and 151°], and the ethanol mol­ecule is linked to the anion by an O—H⃛O hydrogen bond [H⃛O = 1.90 Å, O⃛O = 2.728 (2) Å and O—H⃛O = 171°], to form a centrosymmetric five‐component aggregate. C—H⃛O hydrogen bonds and aromatic π–π‐stacking interactions are absent, but the aggregates are linked into sheets by a single C—H⃛π(arene) hydrogen bond.     

Cocrystals of 1,4‐diethynylbenzene with 1,3‐diacetylbenzene and benzene‐1,4‐dicarbaldehyde exhibiting strong nonconventional alkyne–carbonyl C—H…O hydrogen bonds between the components

Weak interactions between organic molecules are important in solid‐state structures where the sum of the weaker interactions support the overall three‐dimensional crystal structure. The sp‐C—H…N hydrogen‐bonding interaction is strong enough to promote the deliberate cocrystallization of a series of diynes with a series of dipyridines. It is also possible that a similar series of cocrystals could be formed between molecules containing a terminal alkyne and molecules which contain carbonyl O atoms as the potential hydrogen‐bond acceptor. I now report the crystal structure of two cocrystals that support this hypothesis. The 1:1 cocrystal of 1,4‐diethynylbenzene with 1,3‐diacetylbenzene, C₁₀H₆·C₁₀H₁₀O₂, (1), and the 1:1 cocrystal of 1,4‐diethynylbenzene with benzene‐1,4‐dicarbaldehyde, C₁₀H₆·C₈H₆O₂, (2), are presented. In both cocrystals, a strong nonconventional ethynyl–carbonyl sp‐C—H…O hydrogen bond is observed between the components. In cocrystal (1), the C—H…O hydrogen‐bond angle is 171.8 (16)° and the H…O and C…O hydrogen‐bond distances are 2.200 (19) and 3.139 (2) Å, respectively. In cocrystal (2), the C—H…O hydrogen‐bond angle is 172.5 (16)° and the H…O and C…O hydrogen‐bond distances are 2.25 (2) and 3.203 (2) Å, respectively.     

Molecular and Low‐dimensional Coordination Compounds of Copper(II) and 3, 5‐Dimethylpyrazole — Synthesis,Crystal Structure,and Properties

Three 3, 5‐dimethylpyrazole (pz*) copper(II) complexes, [Cu(pz*)₄(H₂O)](ClO₄)₂ ( 1 ), [Cu(pz*)₂(NCS)₂]·H₂O ( 2 ), and [Cu(pz*)₂(OOCCH=CHCOO)(H₂O)]·1.5H₂O ( 3 ), have been synthesized and characterized with single crystal X‐ray structure analysis. 1 crystallizes in the tetragonal space group, 14/m, with a = 14.027 (3) Å, c = 16.301 (5) Å, and Z = 4. 2 crystallizes in the monoclinic space group, P2₁/c, with a = 8.008 (3) Å, b = 27.139 (9) Å, c = 8.934 (3) Å, β = 106.345 (6)°, and Z = 4. 3 crystallizes in the triclinic space group, P1¯, with a = 7.291 (9) Å, b = 10.891 (13) Å, c = 11.822 (14) Å, α = 80.90 (2)°, β = 79.73(2)°, γ = 70.60(2)°, and Z = 2. In 1 , one water molecule and four pz* ligands are coordinated to Cu^II. Two [Cu(pz*)₄(H₂O)]²⁺ units are connected to ClO₄^— via hydrogen bonds. One lattice water molecule is found in the unit cell of 2 , which forms an one‐dimensional chain via intermolecular hydrogen bonds with the N‐H atom of pz*. In 3 , the oxygen atom of the coordinated water molecule is connected with two C=O groups of two neighbouring maleic acid molecules to form a linear parallelogram structure. Another C=O group of maleic acid forms a hydrogen bond with the N‐H atom of pz* to create a two‐dimensional structure. The spectroscopic and bond properties are also discussed.     

Three N2‐benzoyl­oxybenz­amidines: sheet structures built from hard and soft hydrogen bonds and aromatic π–π stacking interactions

Molecules of the title compounds N²‐(benzoyl­oxy)­benz­ami­dine, C₁₄H₁₂N₂O₂, (I), N²‐(2‐hydroxy­benzoyl­oxy)­benz­ami­dine, C₁₄H₁₂N₂O₃, (II), and N²‐benzoyloxy‐2‐hydroxybenzamidine, C₁₄H₁₂N₂O₃, (III), all have extended chain conformations, with the aryl groups remote from one another. In (I), the mol­ecules are linked into chains by a single N—H⋯N hydrogen bond [H⋯N = 2.15 Å, N⋯N = 3.029 (2) Å and N—H⋯N = 153°] and these chains are linked into sheets by means of aromatic π–π stacking interactions. There is one intramolecular O—H⋯O hydrogen bond in (II), and a combination of one three‐centre N—H⋯(N,O) hydrogen bond [H⋯N = 2.46 Å, H⋯O = 2.31 Å, N⋯N = 3.190 (2) Å, N⋯O = 3.146 (2) Å, N—H⋯N = 138° and N—H⋯O = 154°] and one two‐centre C—H⋯O hydrogen bond [H⋯O = 2.46 Å, C⋯O = 3.405 (2) Å and C—H⋯O = 173°] links the mol­ecules into sheets. In (III), an intramolecular O—H⋯N hydrogen bond and two N—H⋯O hydrogen bonds [H⋯O = 2.26 and 2.10 Å, N⋯O = 2.975 (2) and 2.954 (2) Å, and N—H⋯O = 138 and 163°] link the molecules into sheets.     

A novel hydrogen-bonding N-oxide–sulfonamide–nitro N—H…O synthon determining the architecture of benzenesulfonamide cocrystals

The structures of novel cocrystals of 4-nitropyridine N-oxide with benzenesulfonamide derivatives, namely, 4-nitrobenzenesulfonamide–4-nitropyridine N-oxide (1/1), C₅H₄N₂O₃·C₆H₆N₂O₄S, and 4-chlorobenzenesulfonamide–4-nitropyridine N-oxide (1/1), C₆H₆ClNO₂S·C₅H₄N₂O₃, are stabilized by N—H…O hydrogen bonds, with the sulfonamide group acting as a proton donor. The O atoms of the N-oxide and nitro groups are acceptors in these interactions. The latter is a double acceptor of bifurcated hydrogen bonds. Previous studies on similar crystal structures indicated competition between these functional groups in the formation of hydrogen bonds, with the priority being for the N-oxide group. In contrast, the present X-ray studies indicate the existence of a hydrogen-bonding synthon including N—H…O(N-oxide) and N—H…O(nitro) bridges. We present here a more detailed analysis of the N-oxide–sulfonamide–nitro N—H…O ternary complex with quantum theory computations and the Quantum Theory of Atoms in Molecules (QTAIM) approach. Both interactions are present in the crystals, but the O atom of the N-oxide group is found to be a more effective proton acceptor in hydrogen bonds, with an interaction energy about twice that of the nitro-group O atoms.     

Crystal and Molecular Structure of 1-Methyl-6-O-p-toluenesulfonyl-alpha-D-glucopyranoside Dihydrate

Grown from aqueous solution, 1-methyl-6-O-p-toluenesulfonyl-alpha-D-glucopyranoside dihydrate is monoclinic, space group P2₁, a = 6.6236(4), b = 6.4708(4), c = 20.1758(11) Å; β = 92.836(2)°; Z = 2; V = 863.68(9) ų. The molecules are interconnected in the solid state by O─H … O hydrogen bonds involving bridging water molecules.     

Coordination polymer of uranyl nitrate with 4,4,10,10-Tetramethyl-1,3,7,9-Tetraazaspiro[5.5]undecane-2,8-dione (Spirocarbone, Sk): Synthesis and study of molecular and crystal structures

The coordination polymer {[UO₂(NO₃)₂(C₁₁H₂₀N₄O₂)] · 2H₂O} _n (I) was obtained and examined by X-ray diffraction. The crystals are monoclinic, space group C2/c; a = 23.1386(13), b = 5.41575(15), c = 19.7769(11) Å, β = 125.285(8)°, V = 2023.01(17) ų, ρ_calcd = 2.20 g/cm³, Z = 4. The U atom occupies a special position in the center of inversion. Its coordination polyhedron is a distorted hexagonal bipyramid with axial oxo ligands. In the equatorial plane, the U(1) atom is coordinated by four O atoms of two bidentate nitrate anions and two O atoms of two carbonyl groups of organic spirocarbone (Sk) molecules, which are related by the symmetry operation (0.5 ? x, 0.5 ? y, ?z). In the crystal, polymer chains are parallel to the direction (101). Water molecules are hydrogen-bonded to the N(1) atom of ligand Sk; in addition, they are linked together by the intermolecular hydrogen bonds O(6)-H(6d)…O(6)ⁱ(ⁱ1/2 ? x, ?1/2 + y, 1/2 ? z); H…O 2.11 Å angle O-H…O 160°) and to the nitrate anions by the hydrogen bonds O(6)-H(6e)…O(3)ⁱ; H…O 2.29 Å; the angle O-H…O 149°). In the crystal, hydrogen-bonded water molecules form chains along the axis y that are perpendicular to the coordination polymers. To verify the purity of complex I, the Rietveld refinement of its X-ray powder diffraction pattern was performed. At room temperature, the unit cell parameters are a = 23.2965(6), b = 5.51225(15), c = 19.8588(6) Å, β = 125.6063(17)°, V = 2073.40(10) ų.     

Synthesis,Crystal Structure,and Luminescence of a Three-Dimensional Supramolecular Compound Based on a Dinuclear Tin Cluster

A three-dimensional (3D) supramolecular compound, [(phen)LSnS]₂·(H₂O)₂ (phen = 1,10-phenanthroline, L = mercaptoacetic acid), has been synthesized and the crystal structure was determined by a single crystal X-ray diffraction study. 1 is triclinic, space group P-1 with a = 6.695(1) Å, b = 10.929(2) Å, c = 12.117(2) Å, α = 114.55(3)°, β = 93.53(2)°, γ = 104.06(3)°, and Z = 1. The dinuclear cluster of [(phen)LSnS]₂ and H₂O are linked into a 3D supramolecular framework by a combination of O[sbnd]H…O, C[sbnd]H…O hydrogen bonds and π–π stacking interactions. Its luminescence property is discussed.     

Crystal Structures and Solution Studies of Two Novel Zinc(II) Complexes of a Proton Transfer Compound Obtained from 2, 6‐Pyridinedicarboxylic Acid and 1, 10‐Phenanthroline: Observation of Strong Intermolecular Hydrogen Bonds

The proton transfer compound LH₂ , (phenH⁺)₂(pydc^2—), has been prepared from 1, 10‐phenanthroline, phen, and 2, 6‐pyridinedicarboxylic acid, (dipicolinic acid), pydcH₂. Characterization was performed using solution and solid phase CP/MAS ¹³C NMR and IR spectroscopy. The reactions of this adduct with ZnSO₄·7H₂O and Zn(NO₃)₂·4H₂O give the complexes, [Zn(pydc)₂][Zn(phen)₂(H₂O)₂]·7H₂O (1) and [Zn(phen)₃]₄(H(Hpydc)₂)(NO₃)₇·26H₂O (2) , respectively. These complexes were characterized by ¹H and ¹³C NMR spectroscopy and single crystal X‐ray analysis. The complexes crystallize in the triclinic space group P1 with Z = 2. The unit cell dimensions for complex 1 and 2 are: a = 9.9838(9) Å, b = 14.7483(13) Å, c = 14.8365(13) Å and a = 12.640(4) Å, b = 15.855(5) Å, c = 21.830(7) Å, respectively. In complex 1 (pydc^2—) and phen, are tri‐ and bidentate ligands, respectively, and an anionic [Zn(pydc)₂]^2— and cationic [Zn(phen)₂(H₂O)₂]²⁺ complex are formed simultaneously. In complex 2 , three phen participate in complexation leaving hydrogen‐bis(pyridine‐2‐carboxylate), (H(Hpydc)₂)^— as a supramolecular anion. The fragments (H(Hpydc)₂)^—, 7 NO₃^—, and 26 H₂O in complex 2 are joined together by extensive and strong H‐bonding; therefore, the structure is composed of [Zn(phen)₃]₄⁸⁺, and an anionic hydrogen bond supramolecular assembly with the formula, {(H(Hpydc)₂(NO₃)₇)^8— · 26H₂O}_n. The anionic species (H(Hpydc)₂)^— has a special position at the inversion center, as well as one of the NO₃^— anions, which is disordered over the inversion center. Most of the hydrogen bonds in complex 2 represent strong H‐bonding. The protonation constants of the building blocks of the pydc‐phen adduct, the equilibrium constants for the reaction of (pydc^2—) with phenanthroline and the stoichiometry and stability of the Zn^II complex with LH₂ on aqueous solution were determined by potentiometric pH titration. The solution study results support self‐association between (pydc^2—) and (phenH⁺) with a stoichiometry for the Zn(II) complex similar to that observed for the isolated crystalline complex.     

Amine‐Templated Uranyl Selenates with Layered Structures. I Structural Diversity of Sheets with a U:Se ratio of 1:2

Crystals of four amine‐templated layered uranyl selenates, [C₂H₁₀N₂][(UO₂)(SeO₄)₂(H₂O)](H₂O) ( 1 ), [CH₆N₃]₂[(UO₂)(SeO₄)₂(H₂O)](H₂O)_1.5 ( 2 ), [C₄H₁₂N]₂[(UO₂)(SeO₄)₂(H₂O)] ( 3 ), and [CH₆N₃]₃[(UO₂)₂(SeO₄)₂(H(SeO₄)₂)](H₂O)₂ ( 4 ) were prepared by evaporation from aqueous solution of uranyl nitrate, selenic acid and the respective amine. The structures of all four compounds have been solved by direct methods. The structures of 1 (monoclinic, C2/c, a = 11.787(2), b = 7.7007(10), c = 16.600(3) Å, β = 102.016(14)°, V = 1473.7(4) ų, R₁ = 0.037 for 1743 unique observed reflections), 2 (monoclinic, C2/c, a = 37.314(4), b = 7.1771(6), c = 13.2054(14) Å, β = 109.267(8)°, V = 3338.4(6) ų, R₁ = 0.088 for 3005 unique observed reflections) and 3 (monoclinic, C2/c, a = 27.212(10), b = 7.372(3), c = 23.113(7) Å, β = 117.75(2)°, V = 4103(3) ų, R₁ = 0.073 for 2111 unique observed reflections) are based on sheets of the composition [(UO₂)(SeO₄)₂(H₂O)]^2? consisting of pentagonal [UO₇]^8? pentagonal bipyramids linked via [SeO₄]^2? tetrahedra. The sheets have the same chemical composition but different topologies. The structure of 4 (orthorhombic, P2₁2₁2₁, a = 10.7261(9), b = 13.918(2), c = 18.321(2) Å, V = 2735.1(5) ų, R₁ = 0.050 for 5683 unique observed reflections) contains [(UO₂)₂(SeO₄)₂(H(SeO₄)₂)]^3? sheets parallel to (001). In all four structures, the layers are connected via protonated amine and H₂O molecules.     

4,4′‐Tri­methyl­enedipyridinium bis­[carboxy­methyl­phos­pho­nate(1–)]: a three‐dimensional framework structure built from O—H⃛O,N—H⃛O and C—H⃛O hydrogen bonds

In the title compound, C₁₃H₁₆N₂²⁺·2C₂H₄O₅P⁻, the cation lies across a twofold rotation axis in space group Fdd2. The anions are linked into molecular ladders by two O—H⃛O hydrogen bonds [H⃛O = 1.73 and 1.77 Å, O⃛O = 2.538 (2) and 2.598 (3) Å, and O—H⃛O = 160 and 170°], these ladders are linked into sheets by a single type of N—H⃛O hydrogen bond [H⃛O = 1.75 Å, N⃛O = 2.624 (3) Å and N—H⃛O = 171°] and the sheets are linked into a three‐dimensional framework by a single type of C—H⃛O hydrogen bond [H⃛O = 2.48 Å, C⃛O = 3.419 (4) Å and C—H⃛O = 167°].     

Crystal structure of 1:1 Complexes between urea and two crown ether derivatives of phthalic acid, 2,3,5,6,8,9,11,12,14,15-decahydrobenzo[1,4,7,10,13,16]hexaoxacyclo-octadecin-18,19-dicarboxylic acid (i) and 2,3,5,6,8,9,11,12-octahydro-benzo[1,4,7,10,13]pentaoxacyclopentadecin-15,16-dicarboxylic acid (II)

The crystal structures of the titlke compounds have been determined by X-ray diffraction. Urea, I crystallizes in the triclinic PI space group with cell dimensions a = 8.336(2), b = 11.009(2), c = 13.313(2) Å, α = 105.55(3), β = 103.62(3), γ = 104.63(3)° and Z = 2 final R value 0.072 for 2105 observations. Urea, II crystallizes in the orthorhombic P2₁2₁2₁ space group with cell dimensions a = 8.750(2), b = 10.844(3) and c = 21.215(3) Å and Z = 4, final R value 0.083 for 599 observations. All the hydrogen atoms were located in the complex urea, I ; urea molecules form hydrogen bonded dimers about centers of symmetry, these dimers are sandwiched between macrocyclic rings forming one simple and one bifurcated hydrogen bond from the “endo” hydrogen atoms to the ether oxygen atoms. These units are held by hydrogen bonding between the urea molecules and carboxylic acids in two other units; these hydrogen bonds are cyclic involving eight atoms -(N-H(exo)…O(keto)-C-O-H…O(urea)-C)-. Only one carboxylic acid group per molecule takes part in these hydrogen bonds, the other forms a short, 2.490(7) Å, internal bond to the acceptor keto oxygen atom. N(H)…O bonds range from 2.930(7) to 3.206(7) Å, O(H)…O is 2.475(6) Å. In the complex urea, II each urea is hydrogen bonded to three different host molecules and vice versa; the urea “endo” hydrogen atoms bond to the ether oxygen atoms, while both “exo” hydrogen atoms take part in cyclic hydrogen bonds to carboxylic acids. There is not internal hydrogen bond. N(H)…O bonds range from 2.83 to 3.26(2) A and the O-…O bonds are 2.55 and 2.56(2) Å.     

rac‐1‐Phenyl­ethyl­ammonium carboxy­methyl­phospho­nate(1–): hydrogen‐bonded anion sheets with pendent cations

In the title compound, C₈H₁₂N⁺·C₂H₄O₅P⁻, the anions are linked by two O—H⋯O hydrogen bonds [H⋯O both 1.75 Å, O⋯O = 2.5781 (15) and 2.5834 (15) Å, and O—H⋯O = 169 and 176°] into sheets built from alternating (8) and (32) rings. Each cation is linked to an anion sheet by three N—H⋯O hydrogen bonds [H⋯O = 1.88–2.04 Å, N⋯O = 2.7603 (16)–2.9334 (17) Å and N—H⋯O = 162–166°], such that all the cations pendent from one face of the sheet are of the R configuration, while all those pendent from the opposite face are of the S configuration.     

Synthesis and Comprehensive Characterization of Hydrated Alkaline Earth Metal Salts of 5‐Amino‐1H‐tetrazole

Hydrated alkaline earth metal salts of 5‐amino‐1H‐tetrazole ( B ) were synthesized by reaction of B with a suitable metal hydroxide in water. All compounds were fully characterized by analytical (elemental analysis and mass spectrometry) and spectroscopic (IR, Raman, ¹H and ¹³C NMR) methods. Additionally, the crystal structures of the magnesium [ 1· 4H₂O: triclinic, P$\bar {1}$ , a = 5.940(1) Å, b = 7.326(1) Å,c = 7.383(1) Å, α = 106.10(1)°, β = 106.51(1)°, γ = 111.85(1)°, V = 258.0(1) ų], calcium [ 2· 6H₂O: monoclinic, P2₁/m, a = 6.904(1) Å,b = 6.828(1) Å, c = 10.952(2) Å, β = 94.50(2)°, V = 514.6(1) ų], and strontium [ 3· 6H₂O: orthorhombic, Cmcm, a = 6.987(1) Å, b = 28.394(2) Å, c = 7.007(1) Å, V = 1390.3(2) ų] were determined by low temperature X‐ray diffraction. Additionally, the (gas phase) structure of the 5‐amino‐1H‐tetrazole anion ([ B ]^–) was also studied by natural bond orbital (NBO) analysis [B3LYP/6‐31+G(d,p)]. Lastly, standard tests were used to determine the sensitivity towards impact, friction, and electrostatic discharge of the compounds and the thermal stability was assessed by differential scanning calorimetry (DSC) analysis.     

Hypervalent organoselenium compounds stabilized by intramolecular coordination: synthesis and crystal structures

Two novel hypervalent selenium(IV) compounds stabilized by intramolecular interactions, namely 6‐phenyl‐6,7‐dihydro‐5H‐2,3‐dioxa‐2aλ⁴‐selenacyclopenta[hi]indene, C₁₄H₁₂O₂Se, 14 , and 5‐phenyl‐5,6‐dihydro‐4H‐benzo[c][1,2]oxaselenole‐7‐carbaldehyde, C₁₄H₁₂OSe₂, 15 , have been synthesized by the reaction of 2‐chloro‐1‐formyl‐3‐(hydroxymethylene)cyclohexene with in‐situ‐generated disodium diselenide (Na₂Se₂). The title compounds were characterized by FT–IR spectroscopy, ESI–MS, and single‐crystal X‐ray diffraction studies. For 14 , there is whole‐molecule disorder, with occupancies of 0.605 (10) and 0.395 (10), a double bond between C and Se, and the five‐membered selenopentalene rings are coplanar. The packing is stabilized by π–π stacking interactions involving one of the five‐membered Se/C/C/C/O rings [centroid–centroid (Cg…Cg) distance = 3.6472 (18) Å and slippage = 1.361 Å], as well as C—H…π interactions involving a C—H group and the phenyl ring. In addition, there are bifurcated C—H…Se,O interactions which link the molecules into ribbons in the c direction. For 15 , the C—Se bond lengths are longer than those of 14 . The two five‐membered rings are coplanar. There are no π–π or C—H…π interactions; however, molecules are linked by C—H…O interactions into centrosymmetric dimers, with graph‐set notation R₂²(16).     

Synthesis,Crystal Structure,and Magnetic Properties of {[Cu(phen)]2(C4H2O4)2} · 4.5H2O with C4H4O4 = Maleic Acid

Reaction of CuCl₂ · 2H₂O, phenanthroline, maleic acid and NaOH in CH₃OH/H₂O (1:1 v/v) at pH = 7.0 yielded blue {[Cu(phen)]₂(C₄H₂O₄)₂} · 4.5H₂O, which crystallizes in the monoclinic space group C2/c (no. 15) with cell dimensions: a = 18.127(2)Å, b = 12.482(2)Å, c = 14.602(2)Å, β = 103.43(1)°, U = 3213.5(8)ų, Z = 4. The crystal structure consists of the centrosymmetric dinuclear {[Cu(phen)]₂(C₄H₂O₄)₂} complex molecules and hydrogen bonded H₂O molecules. The Cu atoms are each square‐pyramidally coordinated by two N atoms of one phen ligand and three carboxyl O atoms of two maleato ligands with one carboxyl O atom at the apical position (d(Cu‐N) = 2.008, 2.012Å, equatorial d(Cu‐O) = 1.933, 1.969Å, axial d(Cu‐O) = 2.306Å). Two square‐pyramids are condensed via two apical carboxyl O atoms with a relatively larger Cu···Cu separation of 3.346(1)Å. The dinuclear complex molecules are assembled via the intermolecular π—π stacking interactions into 1D ribbons. Crossover of the resulting ribbons via interribbon π—π stacking interactions forms a 3D network with the tunnels occupied by H₂O molecules. The title complex behaves paramagnetically between 5—300 K, following the Curie‐Weiss law _χm(T—θ) = 0.435 cm³ · mol^—1 · K with θ = 1.59 K.     

Syntheses,Structures and Magnetic Properties of Three New Extended Iron‐containing Heteropolytungstates

Three new extended iron‐containing heteropolytungstates were synthesized and structurally characterized: K₆[{Fe^II(H₂O)₄}₂(H₂W₁₂O₄₂)]·15H₂O ( 1 ), Na₅[{Fe(H₂O)₃}₂{Fe(H₂O)₄}_0.5(H₂W₁₂O₄₂)]·30H₂O ( 2 ) and (H₃O)⁺₂[{Fe(H₂O)₄Fe(H₂O)₃}₂(H₂W₁₂O₄₂)]·20H₂O ( 3 ). 1 and 3 crystallize in the monoclinic system, space group P2₁/n with a = 14.9967(5), b = 10.3872(3), c = 18.8237(6)Å, β = 93.407(1)°, V = 2927.1(2)ų and D_c = 4.151 g cm^—3 for 1 , and space group P2₁/c with a = 12.1794(4), b = 22.4938(4), c = 11.6941(3) Å, β = 105.731(2)°, V = 3083.7(1) ų, and D_c = 4.043 g cm^—3 for 3 . 2 is triclinic, space group P1¯, with a = 12.121(2), b = 12.426(3), c = 13.247(3)Å, α = 68.33(3), β = 71.33(3), γ = 71.44(3)°, V = 1710.7(6)ų and D_c = 3.735 g cm^—3. In all cases, the structures are based on paradodecatungstate polyoxoanions, which are linked by iron ions into chains, layers and a three‐dimensional structure for 1 , 2 and 3 , respectively.