Hydrothermal synthesis and structures of two novel chain-like heteropolymolybdate formed by Keggin cluster units

Two novel heteropolymolybdate, [H₂bpy]₂ [Hbpy] [PCuMo₁₁O₃₉]·H₂O 1 and [H₂bpy]₂ [Hbpy] [PZnMo₁₁O₃₉]·2.75H₂O 2, have been prepared under mild hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction. The two compounds are isostructural and crystallize in the monoclinic space group P2(1)/n (No. 14) with a=13.440(3) Å, b=26.660(5) Å, c=15.240(3) Å, β=99.55(3)°, and Z=4 for the compound 1, and a=13.610(3) Å, b=26.781(5) Å, c=15.205(3) Å, β=100.40(3)°, and Z=4 for the compound 2. Compound 1 and 2 exhibit a zigzag chain structure in which Keggin anions are connected through a common oxygen atom. They are the first characterized compounds containing 1D chains of transition-metal substituted Keggin heteropolymolybdate. Other characterizations by elemental analysis, IR, EPR, TG, and XRPD are also described.     

Hydrothermal synthesis of two copper helical coordination polymers with acentric three-dimensional framework constructing from mixed pyridine carboxylates

Two copper helical coordination polymers, [Cu(2-pc)(3-pc)]_n1 and [Cu(2-pc)(4-pc)]_n2 (2-pc=2-pyridine carboxylate, 3-pc=3-pyridine carboxylate, 4-pc=4-pyridine carboxylate) have been hydrothermally synthesized directly from pyridine carboxylic acids and copper nitrate. The crystal structure were determined by single-crystal X-ray diffraction with the following data: compound 1, orthorhombic, P2₁2₁2₁, a=6.591(3) Å, b=8.692(5) Å, c=20.548(9) Å, V=1177.2(9) Å³, Z=4; compound 2, orthorhombic, Pna2₁, a=21.160(10) Å, b=9.095(5) Å, c=6.401(3) Å, V=1231.9(11) Å³, Z=4. The acentric three-dimensional (3D) framework of 1 is constructed from right-handed helical Cu(2-pc) chains and left-handed Cu(3-pc) helices. As for 2, Cu(2-pc) helical chains, in which left- and right-handed helices are coexisting, and Cu(4-pc) zigzag chains combined together to form acentric 3D architecture of 2 as well. Additionally, besides general spectral characterization, we first introduce generalized 2D correlation spectroscopy to explore the coordination polymers and ascertain the stretching vibration location of carboxylate groups of compounds 1 and 2.     

Structural variations of Sn pyridylphosphonates influenced by an uncommon Sn-N interaction

Four new Sn^II phosphonates have been synthesized by hydrothermal methods, and their structures determined by single-crystal X-ray diffraction. Tin(II) 3-pyridylphosphonate, SnO₃PC₅H₄N (I), crystallizes in P2₁/c with a=4.9595(8) Å, b=10.7673(18) Å, c=13.996(2) Å, and β=93.616(2)°. Tri-tin(II) (μ-3)-oxo-(bis)-4-pyridylphosphonate, Sn₃O(O₃PC₅H₄N)₂ (II), crystallizes in P-1 with a=7.2406(14) Å, b=9.9524(19) Å, c=12.604(3) Å, α=104.510(11)°, β=90.326(11)°, and γ=110.897(11)°. Tin(II) 6-methyl-2-pyridylphosphonate quadrahydrate, Sn(O₃PC₅H₃NCH₃)·0.25H₂O (III), crystallizes in Pna2₁, a=18.955(3) Å, b=9.7543(14) Å, and c=17.833(3) Å. Tin(II) 4-cyanophenylphosphonate, Sn(O₃PC₆H₄CN) (IV), crystallizes in P-1, a=5.0019(3) Å, b=8.4396(5) Å, c=10.3099(6) Å, α=90.352(3)°, β=94.894(3)°, and γ=92.236(4)°. I, II, and IV have ladder-type structures, and III is a layered compound. The structural variations show the effects of the Sn-N interaction on the final structures.     

Building three-dimensional metal phosphites from the corner-shared four-membered rings chain

Three new compounds, a one-dimensional (1D) zinc phosphite, (C₄H₈N₂H₄)[Zn(HPO₃)₂] (I), two three-dimensional (3D) metal phosphites (C₄H₈N₂H₄)[Zn₃(HPO₃)₄] (II) and (C₄H₈N₂H₄)[Zn_(3−x)Co_x(HPO₃)₄(H₂O)₂] (x≈0.83) (III) have been synthesized under hydrothermal conditions templated by piperazine and characterized by single-crystal X-ray diffraction, XRD, IR, UV-vis spectra and SQUID magnetometer. Compound I displays 1D chain-like structure, containing corner-shared (cs) four-membered rings. Interestingly, the structures of II and III show 1D chains similar to those observed in I. It is noteworthy that III represents the first cobalt-substituted zinc-phosphite. Crystal data: I, monoclinic, C2/c, a=17.748(2) Å, b=7.428(9) Å, c=8.8071(11) Å, β=105.345(3)°, V=1091.9 Å³, Z=4. II, Monoclinic P2₁/c, a=9.9435(4) Å, b=10.1438(3) Å, c=17.8164(5) Å, β=95.665(2)°, V=1788.27 Å³, Z=4, and III, Monoclinic P2₁/c, a=7.2338(2) Å, b=15.0238(5) Å, c=9.2153(3) Å, β=107.741(2)°, V=953.88(5) Å³, Z=2.     

Supramolecular assembly of organic bicapped Keggin polyoxometalate

Two novel supramolecular assemblies of organic bicapped Keggin polyoxometalates (pbpy)₈H₃[PW₁₂O₄₀]·2H₂O (1) and (pbpy)₄H[PMo₁₂O₄₀(VO)] (2) (pbpy=5-phenyl-2-(4-pyridinyl)pyridine) have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Crystallographic data for compound (1), C₁₂₈H₁₀₃N₁₆O₄₂PW₁₂, triclinic, space group : a=13.4759(8) Å, b=14.6395(11) Å, c=16.5743(10) Å, α=95.764(2)°, β=102.166(2)°, γ=92.9870(10)°, Z=1, V=3171.1(4) Å³; for compound (2), C₆₄H₄₉N₈O₄₁PMo₁₂V, triclinic, space group : a=11.5377(11) Å, b=12.7552(8) Å, c=14.9599(10) Å, α=72.270(4)°, β=88.916(2)°, γ=67.865(4)°, Z=1, V=1931.0(3) Å³. X-ray analyses show that both 1 and 2 represent rare organic bicapped Keggin structures and are supported by supramolecular interactions to extend into a 3D framework. In particular, the unusual structure feature of compound 2 contains a simultaneously organic and inorganic capped structure.     

Reactivity of cyclopalladated compounds derived from biphenyl-2-ylamine towards carbon monoxide, butyl isocyanide and alkynes

The reactivity of the dimeric cyclopalladated compounds derived from biphenyl-2-ylamine (μ-X)₂[κ²-N2′,C1-1-Pd-2-{(2′-NH₂C₆H₄)C₆H₄}]₂ [X = OAc (1), X = Cl (2)] towards unsaturated organic molecules is reported. Compound 1 reacted with carbon monoxide and ^tbutyl isocyanide producing phenanthridin-6(5H)-one and N-tert-butylphenanthridin-6-amine in 63% and 88% yield, respectively. Compound 2 reacted separately with diphenylacetylene and 3-hexyne, affording the mononuclear organopalladium compounds [κ²-N2″,C1-η²-C2,C3- 1-Pd{(R-CC-R)₂-2′-(2″-NH₂C₆H₄)C₆H₄}Cl] [R = Ph (5), R = Et (6)] in 50-60% yield, which derived from the insertion of two alkyne molecules into the C-Pd σ bonds of 2. The crystal structure of compounds 5 and 6 has been determined. Compound 5 crystallized in the monoclinic space group P2₁/n with a = 13.3290(10) Å, b = 10.6610(10) Å and c = 22.3930(10) Å and β = 100.2690(10)°. Compound 6 crystallized in the triclinic space group with a = 7.271(7) Å, b = 10.038(3) Å and c = 16.012(5) Å, and α = 106.79(3)°, β = 96.25(4)° and γ = 99.62(4)°. The crystal structures of 5 and 6 have short intermolecular Pd-Cl?H-N-Pd non-conventional hydrogen bonds, which associated the molecules in chains in the first case and in dimers in the second.     

Ab-initio crystal structure of hydroxy adipate of nickel and hydroxy subarate of nickel and cobalt from synchrotron powder diffraction and magnetic properties

Organic-inorganic hybrid compounds Ni(II)₅(OH)₆(C₆H₈O₄)₂(1), Ni(II)₅(OH)₆(C₈H₁₂O₄)₂(2) and Co(II)₅(OH)₆(C₈H₁₂O₄)₂(3) have a similar layered structure as determined ab initio from synchrotron powder diffraction analysis. The metal sites are octahedrally coordinated by O atoms. The slabs are built from edge-sharing octahedra in such a way that channels with an average size of 4 Å are formed. Bis-bidentate and bridging dicarboxylate anions lead to a 3D framework. The compounds (1) and (2) order antiferromagnetically below T_N=26.5 and 19.3 K, respectively, while (3) is ferrimagnetic with T_C=16.2 K. Crystal data for compounds are as follows: (1)a=11.6504(1) Å, b=6.8021(3) Å, c=6.3603(1) Å, α=73.52(1)°, β=99.69(1)°, γ=96.16(1)°, R_B=0.070, 668 reflections; (2)a=13.9325(1) Å, b=6.7893(1) Å, c=6.3534(4) Å, α=73.63(1)°, β=95.14(1)°, γ=91.80(1)°, R_B=0.052, 804 reflections; (3)a=13.9806(1) Å, b=6.9588(1) Å, c=6.3967(1) Å, α=73.05(1)°, β=94.51(1)°, γ=92.19(1)°, R_B=0.048, 410 reflections. The space group is P−1 for the three compounds.     

Synthesis, structure of [H3dien]·(MF6)·H2O (M=Cr, Fe) and Fe Mössbauer study of [H3dien]·(FeF6)·H2O

Single crystals of [H₃dien]·(FeF₆)·H₂O (I) and [H₃dien]·(CrF₆)·H₂O (II) are obtained by solvothermal synthesis under microwave heating. I is orthorhombic (Pna2₁) with a=11.530(2) Å, b=6.6446(8) Å, c=13.787(3) Å, V=1056.3(2) Å³ and Z=4. II is monoclinic (P2₁/c) with a=13.706(1) Å, b=6.7606(6) Å, c=11.3181(9) Å, β=99.38(1)°, V=1034.7(1) Å³ and Z=4. The structure determinations, performed from single crystal X-ray diffraction data, lead to the R₁/wR₂ reliability factors 0.028/0.066 for I and 0.035/0.102 for II. The structures of I and II are built up from isolated FeF₆ or CrF₆ octahedra, water molecules and triprotonated amines. In both structures, each octahedron is connected by hydrogen bonds to six organic cations and two water molecules. The iron-based compound is also characterized by ⁵⁷Fe Mössbauer spectrometry: the hyperfine structure confirms the presence of Fe³⁺ in octahedral coordination and reveals the existence of paramagnetic spin fluctuations.     

Two isotypic diphosphates LiM2H3(P2O7)2 (M=Ni, Co) containing ferromagnetic zigzag MO6 chains

Two new isotypic phosphates LiNi₂H₃(P₂O₇)₂ (1) and LiCo₂H₃(P₂O₇)₂ (2) have been hydrothermally synthesized and structurally characterized by the single-crystal X-ray diffraction technique. They crystallize in the monoclinic space group C2/c with the lattice: a=10.925(2) Å, b=12.774(3) Å, c=8.8833(18) Å, β=123.20(3)° for 1 and a=10.999(2) Å, b=12.863(3) Å, c=8.9419(18) Å, β=123.00(3)° for 2. The transition metal atoms are octahedrally coordinated, whereas the lithium and phosphorus atoms are all tetrahedrally coordinated. As the lithium-induced derivatives of MH₂P₂O₇ (M=Ni, Co), 1 and 2 possess the same structure with MH₂P₂O₇ in terms of topology, comprising the MO₆ zigzag chains and P₂O₇ as the interchain groups. The magnetisms of 1 and 2 could be interpreted by adopting a quasi-one-dimensional (1D) zigzag chain model as that in their parent compounds: both 1 and 2 have ferromagnetic (FM) NiO₆/CoO₆ chains; 1 shows a FM cluster glass behavior at low temperatures, which is originated from the possible antiferromagnetic (AFM) next-nearest-neighbour intrachain interactions; 2 shows a AFM ordering at T_N=2.6 K and a metamagnetic transition at H_C=4.2 kOe at 1.8 K.     

Os(CO)2(η-SC5H4N(O))(η-SC5H4N): structural evidence for the transformation of pyridine-2-thione N-oxide to pyridine-2-thiolate in osmium complexes

The reaction of Os₃(CO)₁₂ with an excess of 1-hydroxypyridine-2-thione and Me₃NO gives three mononuclear osmium complexes Os(CO)₂(η²-SC₅H₄N(O))₂ (1), Os(CO)₂(η²-SC₅H₄N(O))(η²-SC₅H₄N) (2), and Os(CO)₂(η²-SC₅H₄N)₂ (3). The results of single-crystal X-ray analyses reveal that complex 1 contains two O,S-chelate pyridine-2-thione N-oxide (PyOS) ligands, whereas complex 2 contains one O,S-chelate PyOS and one N,S-chelate pyridine-2-thiolate group. The unique structure of 2 provides evidence of the pathway for this transformation. When this reaction was monitored by ¹H NMR spectroscopy the triosmium complexes Os₃(CO)₁₀(μ-H)(μ-η¹-S-C₅H₄N(O)) (4) and Os₃(CO)₉(μ-H)(μ-η¹:η²-SC₅H₄N(O)) (5) were identified as intermediates in the formation of the mononuclear final products 1-3. The proposed pathway is further supported by the observation of several dinuclear osmium intermediates by electrospray ionization mass spectrometry. In addition, the reaction of Os₃(CO)₁₂ with 1-hydroxypyridine-2-thione in the absence of Me₃NO at 90 °C generated mononuclear complex 2 as the major product along with smaller amounts of complexes 1 and 3. These results suggest that the N-oxide facilitates the decarbonylation reaction. Crystal data for 1: monoclinic, space group C2/c, a = 26.9990(5) Å, b = 7.6230(7) Å, c = 14.2980(13) Å, β = 101.620(2)°, V = 2882.4(4) ų, Z = 8. Crystal data for 2: monoclinic, space group C2/c, a = 5.7884(3) Å, b = 13.9667(7) Å, c = 17.2575(9) Å, β = 96.686(1)°, V = 1385.69(12) ų, Z = 4.     

Synthesis and characterization of two novel pyridine-containing framework gallium ethylenediphosphonates

Two novel gallium diphosphonates, (C₅H₅N)Ga₃F(O₃PC₂H₄PO₃)₂ (I) (triclinic, P-1, a=8.2880(12) Å, b=11.7197(16) Å, c=11.7601(17) Å, α=71.589(3)°, β=70.577(3)°, γ=77.313(3)°, V=1013.7(2) Å³, Z=2, R₁=0.0352, wR₂=0.0980) and (C₅H₅NH)₂[Ga₄F₂(O₃PC₂H₄PO₃)₃] (II) (triclinic, P-1, a=8.670(4) Å, b=9.742(3) Å, c=10.406(2) Å, α=81.44(3)°, β=65.83(5)°, γ=67.16(3)°, V=739.0(4) Å³, Z=2, R₁=0.0600, wR₂=0.1495) have been synthesised by solvothermal methods in the presence of pyridine and their structures determined using single-crystal X-ray diffraction data. Both compounds I and II are composed of various Ga-centered polyhedra and ethylenediphosphonate groups that link together to form framework materials with one- and two-dimensional channel systems, respectively. The two structures are formed in the presence of structure-directing pyridine molecules that are directly bound to some of the Ga atoms in I, and are protonated as pyridinium cations in II. Compounds I has a charge-neutral framework, while compound II has an anionic framework. Both materials provide rare examples of organically structure-directed framework metal diphosphonate materials.     

The cyclopalladation reaction of 2-phenylaniline revisited

2-Phenylaniline reacted with Pd(OAc)₂ in toluene at room temperature for 24 h in a one-to-one molar ratio and with the system PdCl₂, NaCl and NaOAc in a 1 (2-phenylaniline):1 (PdCl₂):2 (NaCl):1 (NaOAc) molar ratio in methanol at room temperature for one week to give the dinuclear cyclopalladated compounds (μ-X)₂[Pd{κ²-N2′,C1-2-(2′-NH₂C₆H₄)C₆H₄}]₂ [1a (X = OAc) and 1b (X = Cl)] in high yield. Moreover, the reaction between 2-phenylaniline and Pd(OAc)₂ in one-to-one molar ratio in acid acetic at 60 °C for 4 h, followed by a metathesis reaction with LiBr, allowed isolation of the dinuclear cyclopalladated compound (μ-Br)₂[Pd{κ²-N2′,C1-2-(2′-NH₂C₆H₄)C₆H₄}]₂ (1c) in moderate yield. A parallel treatment, but using monodeuterated acetic acid (DOAc) as solvent in the cyclopalladation reaction, allowed isolation of a mixture of compounds 1c, 1c_d1 [Pd{κ²-N2′,C1-2-(2′-NH₂C₆H₄)C₆H₄](μ-Br)₂[Pd{κ²-N2′,C1-2-(2′-NH₂C₆H₄)-3-d-C₆H₃] and 1c_d2 (μ-Br)₂[Pd{κ²-N2′,C1-2-(2′-NH₂C₆H₄)-3-d-C₆H₃}]₂ in moderate yield and with a deuterium content of ca. 60%. 1a and 1b reacted with pyridine and PPh₃ affording the mononuclear cyclopalladated compounds [Pd{κ²-N2′,C1-2-(2′-NH₂C₆H₄)C₆H₄}(X)(L)] [2a (X = OAc, L = py), 2b (X = Cl, L = py), 3a (X = OAc, L = PPh₃) and 3b (X = Cl, L = PPh₃)] in a yield from moderate to high. Furthermore, 1a reacted with Na(acac) · H₂O to give the mononuclear cyclopalladated compound 4 [Pd{κ²-N2′,C1-2-(2′-NH₂C₆H₄)C₆H₄}(acac)] in moderate yield. ¹H NMR studies in CDCl₃ solution of 2a, 2b, 3a, 3b and 4 showed that 2a and 3a presented an intramolecular hydrogen bond between the acetato ligand and the amino group, and were involved in a dynamic equilibrium with water present in the CDCl₃ solvent; and that the enantiomeric molecules of 2b and 4 were in a fast exchange at room temperature, while they were in a slow exchange for 2a, 3a and 3b. The X-ray crystal structures of 3b and 4 were determined. 3b crystallized in the triclinic space group with a = 9.9170(10), b = 10.4750(10), c = 12.0890(10) Å, α = 98.610(10)°, β = 94.034(10)° and γ = 99.000(10)° and 4 in the monoclinic space group P2₁/a with a = 11.5900(10), b = 11.2730(10), c = 12.2150(10) Å, α = 90°, β = 107.6560(10)° and γ = 90°.     

Crystal chemistry of thorium nitrates and chromates

The structures and infrared spectra of six novel thorium compounds are reported. Th(NO₃)₂(OH)₂(H₂O)₂ (1) crystallizes in space group C2/c, a=14.050(1), b=8.992(7), c=5.954(5) Å, β=101.014(2)°. K₂Th(NO₃)₆ (2), P-3, a=13.606(1), c=6.641(6) Å. (C₁₂H₂₈N)₂Th(NO₃)₆ (3), P2₁/c, a=14.643(4), b=15.772(5), c=22.316(5) Å, β=131.01(1)°. KTh(NO₃)₅(H₂O)₂ (4), P2₁/c, a=10.070(8), b=12.731(9), c=13.231(8) Å, β=128.647(4)°. Th(CrO₄)₂(H₂O)₂ (5), P2₁/n, a=12.731(1), b=9.469(8), c=12.972(1) Å, β=91.793(2)°. K₂Th₃(CrO₄)₇(H₂O)₁₀ (6), Ama2, a=19.302(8), b=15.580(6), c=11.318(6) Å. The coordination polyhedra about Th in these structures are diverse. Th is coordinated by 9 O atoms in 5 and 6, seven of which are from monodentate (CrO₄) tetrahedra and two are (H₂O). The Th in compound 1 is coordinated by ten O atoms, four of which are O atoms of two bidentate (NO₃) triangles and six of which are (OH) and (H₂O). In compounds 2, 3 and 4 the Th is coordinate by 12 O atoms. In 2 and 3 there are six bidentate (NO₃) triangles, and in 4 ten of the O atoms are part of five bidentate (NO₃) triangles and the others are (H₂O) groups. The structural units of these compounds consist of a chain of thorium and nitrate polyhedra (1), isolated thorium hexanitrate clusters (2, 3), an isolated thorium pentanitrate dihydrate cluster (4), and a sheet (6) and framework (5) of thorium and chromate polyhedra. These structures illustrate the complexity inherent in the crystal chemistry of Th.     

Two new hydrogen bond-supported supramolecular compounds assembly from polyoxovanadate and organoamines

Two novel organic-inorganic hybrid compounds based on organoamines and polyoxovanadates formulated as (H₂dien)₄[H₁₀V₁₈O₄₂(PO₄)](PO₄)·2H₂O (1) (dien=diethylenetriamine) and (Him)₈[HV₁₈O₄₂(PO₄)] (2) (im=imidazole) have been prepared under hydrothermal conditions by using different starting materials, and characterized by elemental analyses, IR, ESR, XPS, TGA and single-crystal X-ray diffraction analyses. Crystal data for compound 1: C₁₆H₇₄N₁₂O₅₂V₁₈P₂, Monoclinic, space group C2/c, a=23.9593(4) Å, b=13.0098(2) Å, c=20.1703(4) Å, β=105.566(3)°, V=6056.6(19) Å³, Z=4; for compound 2, C₂₄H₄₁N₁₆O₄₆V₁₈P, Tetragonal, space group I4/mmm, a=13.5154(8) Å, b=13.5154(8) Å, c=19.1136 Å, β=90°, V=3491.4(3) Å³, Z=2. Compound 1 consists of protonated diens together with polyoxovanadates [H₁₀V₁₈O₄₂(PO₄)]⁵⁻. Compound 2 is composed of protonated ims and polyoxovanadates [HV₁₈O₄₂(PO₄)]⁸⁻. There are hydrogen-bonding interactions between polyoxovanadates and different organoamines in 1 and 2. Polyoxovanadates are linked through H₂dien into a three-dimensional network via hydrogen bonds in 1, while polyoxovanadates are linked by Him into a two-dimensional layer network via hydrogen bonds in 2. The crystal packing patterns of the two compounds reveal various supramolecular frameworks.     

Hydrothermal synthesis, crystal structure, thermal behavior and spectroscopic and magnetic properties of two new organically templated fluoro-vanadyl-hydrogenarsenates: (R)0.5[(VO)(HAsO4)F] (R: Ethylenediammonium and piperazinium)

Two new fluoro-vanadyl-hydrogenarsenate compounds templated by ethylenediamine and piperazine with formula, (C₂N₂H₁₀)_0.5[(VO)(HAsO₄)F] (1) and (C₄N₂H₁₂)_0.5[(VO)(HAsO₄)F] (2), respectively, have been synthesized by using mild hydrothermal conditions under autogenous pressure. The crystal structures have been solved from single-crystal X-ray diffraction data. The phases crystallize in the P2₁/c monoclinic space group with the unit-cell parameters a=7.8634(4) Å, b=7.7658(4) Å, c=10.4195(6) Å, β=101.524(5)° for compound (1) and a=6.301(1) Å, b=10.244(1) Å, c=10.248(1) Å and β=95.225(1)° for compound (2). These phases exhibit a layered inorganic framework. In both cases, the structure is built from secondary building units (SBU) which are formed by [V₂O₈F₂] edge-shared dimeric vanadyl octahedra, connected by the vertices to two hydrogenarsenate tetrahedra. The repetition of this SBU unit originates sheets along the [1 0 0] direction. The ethylenediammonium and piperazinium cations are located inside the interlayer space. The limit of thermal stability for compounds (1) and (2) is, approximately, 250 and 230 °C, respectively. Near this temperature, both phases loose their organic cations and the fluoride anions. The diffuse reflectance spectra confirm the presence of vanadyl ions, in which the vanadium(IV) cations have a d¹ electronic configuration in a slightly distorted octahedral environment. ESR spectra of both phases are isotropic with mean g-values of 1.93 and 1.96 for ethylendiamine and piperazine phases, respectively. Magnetic measurements for (1) and (2) indicate the existence of antiferromagnetic exchange couplings.     

New indium selenite-oxalate and indium oxalate with two- and three-dimensional structures

Two new indium(III) compounds with extended structures, [In₂(SeO₃)₂(C₂O₄)(H₂O)₂]·2H₂O (I) and [NH₃(CH₂)₂NH₃][In(C₂O₄)₂]₂·5H₂O (II), have been prepared under mild hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction, thermogravimetric analysis and infrared spectroscopy. Compound I crystallizes in the triclinic system, space group P-1, with a=5.2596(11) Å, b=6.8649(14) Å, c=9.3289(19) Å, α=101.78(3)°, β=102.03(3)°, γ=104.52(3)°, while compound II crystallizes in the orthorhombic system, space group Fdd2, with a=15.856(3) Å, b=31.183(6) Å, c=8.6688(17) Å. In compound I, indium-selenite chains are bridged by oxalate units to form two-dimensional (2D) In₂(SeO₃)₂C₂O₄ layers, separated by non-coordinating water molecules. In compound II, the indium atoms are connected through the oxalate units to generate a 3D open framework containing cross-linked 12- and 8-membered channels.     

Luminescent zinc and cadmium complexes incorporating 1,3,5-benzenetricarboxylate and a protonated kinked organodiimine: From a hydrogen-bonded layer motif to thermally robust two-dimensional coordination polymers

Hydrothermal treatment of zinc chloride, 1,3,5-benzenetricarboxylic acid (H₃BTC), and 4,4′-dipyridylamine (dpa) afforded two different complexes depending on reaction conditions, which were characterized by single-crystal X-ray diffraction, infrared spectroscopy, and elemental analysis. Under acidic conditions, a discrete neutral molecular species with formulation [Zn(HBTC)₂(Hdpa)₂] (1) was isolated, which aggregates into two-dimensional hydrogen-bonded layers. Under more basic conditions, the two-dimensional layered coordination polymer [Zn(BTC)(Hdpa)] (2) is obtained, which manifests covalent linkage of [Zn(BTC)(Hdpa)] serpentine chain motifs into 3-connected undulating 4.8² topology 2-D layers. Both 1 and 2 possess tetrahedral coordination at Zn. Use of cadmium nitrate in the synthesis resulted in [Cd(BTC)(H₂O)(Hdpa)] (3), which displays a similar layer topology as 2 but with significant adjustments imparted by octahedral coordination at Cd. In all cases, supramolecular hydrogen bonding promoted by Hdpa ligands provide an important assistive structure-directing role. All materials display blue luminescence upon excitation with ultraviolet light, ascribed to intraligand transitions. Crystallographic data: 1: monoclinic, C2/c, a=25.389(6) Å, b=9.811(2) Å, c=17.309(4) Å, and β=128.957(3)°, 2: monoclinic, P2₁/c, a=13.212(17)c, b=17.15(2) Å, c=7.506(10) Å, and β=93.71(2)°, and 3: monoclinic, C2/c, a=14.241(6) Å, b=15.218(6) Å, c=17.976(7) Å, and β=109.330(6)°.     

Metal phosphonates containing pyridyl N-oxide groups: Syntheses of Cd{(2-C5H4NO)CH(OH)PO3}(H2O)2 and Zn{(4-C5H4NO)CH(OH)PO3} with chain and layer structures

This paper reports the syntheses and characterization of two phosphonate compounds Cd{(2-C₅H₄NO)CH(OH)PO₃}(H₂O)₂ (1) and Zn{(4-C₅H₄NO)CH(OH)PO₃} (2) based on hydroxy(2-pyridyl N-oxide)methylphosphonic and hydroxy(4-pyridyl N-oxide)methylphosphonic acids. Compound 1 has a chain structure in which dimers of edge-shared {CdO₆} octahedra are linked by {CPO₃} tetrahedra through corner-sharing. The pyridyl rings reside on the two sides of the inorganic chain. Compound 2 has a layer structure where the inorganic chains made up of corner-sharing {ZnO₄} and {CPO₃} tetrahedra are covalently connected by pyridyl N-oxide groups. Crystal data for 1: triclinic, space group , a=6.834(1) Å, b=7.539(1) Å, c=10.595(2) Å, α=84.628(3)°, β=74.975(4)°, γ=69.953(4)°. For 2: triclinic, space group , a=5.219(1) Å, b=8.808(2) Å, c=9.270(2) Å, α=105.618(5)°, β=95.179(4)°, γ=94.699(4)°.     

Synthesis and characterization of two novel organocation containing group 13 metal ethylenediphosphonates

Two novel group 13 metal diphosphonates: (H₃NC₃H₆NH₃)₂[Al₂F₆(O₃PC₂H₄PO₃)]·H₂O (1) (monoclinic, C2/c, a=16.9697(7) Å, b=8.0273(4) Å, c=16.3797(8) Å, β=117.762(2)°, Z=4, R₁=4.66%, wR₂=11.82%), and (H₃NC₃H₆NH₃)[Ga₂F₄(O₃PC₂H₄PO₃)] (2) (triclinic, P-1, a=5.398(7) Å, b=8.122(6) Å, c=15.839(18) Å, α=78.89(4)°, β=89.60(7)°, γ=79.35(6)°, Z=2, R₁=2.90%, wR₂=3.17%) have been synthesized by solvothermal methods in the presence of the propyldiammonium cations and their structures determined using single and micro-crystal X-ray diffraction data, respectively. The structures of 1 and 2 are closely related and contain dimers of edge-sharing trivalent metal centered octahedra that are linked together by the ethylenediphosphonate groups to form chains and aperture-containing layers, respectively. The propyldiammonium cations surround the aluminum diphosphonate chains in 1 and separate the gallium diphosphonate layers in 2. Both compounds 1 and 2 are examples of metal phosphonate materials containing only one type of octahedral-tetrahedral secondary building unit (SBU-4).     

A group of new selenite-chlorides of strontium and d-metals (Co,Ni): Synthesis, thermal behavior and crystal chemistry

The new selenite-chlorides with composition Sr₃(SeO₃)₂Cl₂ (I) and Sr₂M(SeO₃)₂Cl₂ (M=Co, Ni (II and III)) were obtained. They crystallize in monoclinic system I: space group C2/m, a=13.203(2) Å, b=5.5355(8) Å, c=6.6170(10) Å, β=95.89(1)°, Z=2; II Space group P2₁/n, a=5.3400(10) Å, b =6.4279(6) Å, c=12.322(1) Å, β=92.44(1)°, Z=2; III: space group P2₁/n, a=5.3254(11) Å, b=6.4363(13) Å, c=12.197(2), β=92.53(3)°, Z=2. All three compounds are constructed in the same manner. Sr polyhedra form infinite layers, which are interconnected into a 3D framework by means of Sr polyhedra in the case of I or Co and Ni polyhedra in the case of II and III. Se atoms are situated inside the channels of the 3D framework. The topological analysis of ELF for I confirmed that the lone electron pairs of SeO₃ groups are located inside these channels.