Phase transition behavior and structure of the thermotropic liquid crystal 6‐{[(4′‐{[(undecyl)carbonyl]oxy}biphenyl‐4yl)carbonyl]oxy}‐1‐hexyne

The phase transition behaviors and corresponding structures of 6‐{[(4′‐{[(undecyl)carbonyl]oxy}biphenyl‐4yl)carbonyl]oxy}‐1‐hexyne (A4EE11) were investigated using differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and wide angle X‐ray diffraction (WAXD). In comparison with the published homologues, 5‐{[(4′‐heptoxy‐biphenyl‐4‐yl)carbonyl]oxy}‐1‐pentyne (A3EO7) which shows a monotropic smectic A (SmA) phase and a metastable monotropic smectic C (SmC) phase; 5‐{[(4′‐heptoxy‐biphenyl‐4‐yl)oxy]carbonyl}‐ 1‐pentyne (A3E'O7) that exhibits three enantiotropic stable liquid crystalline (LC) phases, SmA phase, SmC phase and smectic X (SmX) phase; 5‐{[(4′‐heptoxy‐biphenyl‐4‐yl)carbonyl]oxy}‐1‐undecyne (A9EO7) which has a monotropic SmA phase and a metastable crystal phase, A4EE11 integrates the enantiotropy, monotropy and metastability of the LC phases of those three compounds. Upon cooling from isotropic state to room temperature, in the temperature range of 62.0 to 58.5°C, A4EE11 shows an enantiotropic smectic A (SmA) phase with a layer spacing d=32.69Å. Further lowering the temperature, it enters into a metastable monotropic smectic B (SmB) phase with a longer layer spacing d=34.22Å which has a tendency towards crystallization. The metastability of the liquid crystalline phase may associate to the linkage order of the ester bridge between the mesogenic core and the flexible spacer. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Spectroscopic and crystal structure analysis of diamminebis(2,4,6‐triiodophenolato‐O) copper(II)

The crystal structure of [Cu(C₆H₂I₃O)₂(NH₃)₂] (CCDC 238896) has been determined by x‐ray diffraction. This monomeric centrosymmetric Cu(II) complex crystallizes in the monoclinic system. The CuO₂N₂ coordination sphere is trans ‐planar, [Cu–O: 1.943(5) Å and Cu‐N: 1.972(7)] with the fifth and sixth coordination sites occupied by I atoms from the phenoxide ions [Cu–I₁: 3.3552(8) Å] to form a tetragonally elongated octahedral structure for CuO₂N₂I₂ coordination. The complex molecules hold together in a one dimensional chain true [100] direction by intermolecular hydrogen bonds. Differantial scanning calorimeter, FTIR and magnetic susceptibility measurements were also performed in order to identify the title complex. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis and crystal structure determination of 6,7‐dihydro‐2‐methoxy‐4‐(substituted)‐5H ‐benzo[6,7]cyclohepta[1,2‐b ]pyridine‐3‐carbonitrile

The compounds 6,7‐dihydro‐2‐methoxy‐4‐(4‐methylphenyl)‐5H ‐benzo[6.7]cyclohepta[1,2‐b ]pyridine‐3‐carbonitrile (compound IIIa) and 4‐(4‐chlorophenyl)‐6,7‐dihydro‐2‐methoxy‐5H ‐benzo[6,7]cyclohepta[1,2‐b ]pyridine‐3‐carbonitrile (compound IIIb) were synthesized and their structures have been determined from three dimensional X‐ray data using direct method and refined by full matrix least squares with anisotropic thermal parameters for non‐hydrogen atoms to conventional R(gt) of 0.036 and 0.038 for the two compounds respectively. For compound (IIIa) the crystals are monoclinic, space group C_c, with a=11.2909 (5) Å, b=17.7755(8) Å, c=9.1437(4) Å and β=95.428(3)°, while the crystals of the second compound (IIIb) are triclinic, space group P1, with a=8.7465(3)Å, b=10.3958(3)Å, c=10.9011(4)Å, α= 108.3870(10)°, β=101.3741(12)°, γ=97.9594(12)°. The molecular structure of the two compounds have nearly the same configuration, where the cyclohepta ring takes the boat shape and the methoxy and the carbonitrile groups are attached at the same position C₂ and C₈. The difference occurs only at the position C₄, where the substituent is methylphenyl for compound (IIIa) and chlorophenyl for the other. The bond lengths, valency angles and the hydrogen bonding were calculated and fully discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Interaction in the molten system Rb2O‐P2O5‐TiO2‐NiO. Crystal structure of the langbeinite‐related Rb2Ni0.5Ti1.5(PO4)3

The interaction in the molten system Rb₂O‐P₂O₅‐TiO₂‐NiO was investigated at different molar ratios Rb/P = 0.5‐1.3, fixed Ti/P = 0.15, Ti/Ni = 1.0 at temperature range 1073–953 K. The conditions of formation of complex phosphates RbTi₂(PO₄)₃, Rb₂Ni_0.5Ti_1.5(PO₄)₃ and RbNiPO₄ have been determined. The new phosphate Rb₂Ni_0.5Ti_1.5(PO₄)₃ (space group P2₁3, a = 9.9386(2) Å) has been obtained and investigated by the single crystal X‐ray diffraction and FTIR‐spectroscopy. It has langbeinite‐like structure, that is built up from mixed (Ni/Ti)O₆‐octahedra and РО₄‐tetrahedra. Rubidium atoms are located in closed cavities of 3D‐framework.     

Synthesis,crystal structure and photophysical studies on a ruthenium(II) carbonyl hydrido compound based on 2,2′‐bipyridyl‐5,5′‐dicarboxylic acid (H2bpdc)

A novel complex, namely [Ru^II(PPh₃)(CO)(H)(Hbpdc)]·2MeOH ( 1 ) (H₂bpdc = 2,2′‐bipyridyl‐5,5′‐dicarboxylic acid), has been synthesized from the reaction of H₂bpdc with [Ru^II(PPh₃)₃(CO)(H)₂] in methanol under mild condition and characterized by elemental analysis, IR spectrum, ESI mass spectrometry, and single crystal X‐ray diffraction. The structure shows that the complex crystallizes in the monoclinic space group P2₁/c with unit cell parameters a = 11.8984(13) Å, b = 16.5180(18) Å, c = 25.5322(19) Å, β = 115.302(4)°, V = 4536.6(8) ų, Z = 4. This compound features a 1‐D supramolecular chain constructed via hydrogen bonds. Its photophysical properties have been investigated in MeOH solution and in the solid state at room temperature.     

Synthesis,crystal structure and spectral analysis of diaquatetrakis(N‐methylimidazole)Ni(II)(2,4,6‐tribromophenol)

Diaquatetrakis(N‐methylimidazole)Ni(II)(2,4,6‐tribromophenol), Ni(H₂O)₂(C₃N₂(CH₃))₄^.2(C₆H₃Br₃O), was synthesized via reaction of nickel sulphate and 2,4,6‐tribromophenolate in aqueous media in the presence of N‐methyl imidazole and sodium hydroxide. The complex crystalizes in the triclinic space group P1 with one formula unit of Ni(C₃H₃N₂(CH₃))₄(H₂O)₂.2(C₆H₃Br₃O) in the cell. The coordination around the Ni(II) ion is a slightly distorted octahedron, involving four N atoms from four different di(N‐methyl imidazole) ligand in the basal plane. The two oxygen atoms of the water molecules located at the apical positions result in an octahedral coordination. The two tribomophenol groups in the unit cell are connected via hydrogen‐bonds to the atoms of the coordination sphere, to build one dimensional chains along the a‐axis. For characterization of complex FTIR, UV spectroscopy, DSC and TGA thermal analysis were performed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis,crystal structure and vibrational characterization of bis‐μ‐peroxo‐hexacarbonatodicerate(IV) complexes of rubidium and cesium

The new compounds Rb₈[Ce(O₂)(CO₃)₃]₂ · 12 H₂O (1) and Cs₈[Ce(O₂)(CO₃)₃]₂ · 10 H₂O (2) were obtained from the reaction of hydrogen peroxide and Ce(III) in saturated alkali carbonate solutions. The crystal structures and the unit cell parameters of (1) triclinic, P‐1 with a = 8.973(2) Å, b = 10.815(2) Å, c = 11.130(3) Å, α = 66.992(2)°, β = 68.337(2)°, γ = 74.639(2)°, V_EZ = 914.7(4) ų, Z = 2, and (2) orthorhombic, Pbca, a = 19.3840(16) Å, b = 18.528(2) Å, c = 10.487(3) Å, V_EZ = 3766.4(13) ų, Z = 8, were determined. Both compounds contain the bis‐µ‐peroxo‐hexacarbonatodicerate(IV)‐ion, [(CO₃)₃Ce(O₂)₂Ce(CO₃)₃]^8‐. IR and Raman spectra were measured and discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis,characterization and crystal structure of a novel 3‐D copper(II) polymer with bent N‐containing ligand

An exploration of the mixed‐ligand system under hydrothermal condition, has led to the isolation of a 3‐D novel framework {[Cu₂(mp)L₂)(H₂O)₂]·6H₂O}_n ( 1 ) (mp = benzene‐1,2,4,5‐ tetracarboxylate tetraanion, L = 4‐(5‐(pyridin‐4‐yl)‐1,3,4‐thiadiazol‐2yl)pyridine). Single‐crystal X‐ray analyses reveal that it crystallizes in the triclinic space group P‐1, a = 8.807(4) Å, b =11.139(6) Å, c = 11.291(5) Å, α=75.337(7), β = 73.584(5), γ= 66.795(5)°. The Cu^II ions are linked into an extended 2‐D grid net via mp molecules. Further these layers are united together through the bridging L to form a 3‐D structure, which exhibits a new 4‐connected topological network. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal structure,thermal analysis and IR spectrometric investigation of bis (2‐amino‐6‐methyl) pyridinium sulfate

The synthesis method, crystal structure determination, phase transitions studied by thermal analysis and IR spectrometric investigation of 2C₆H₉N₂⁺.SO₄^2– are reported. The compound crystallizes in the monoclinic space group C2/c (no. 15) with a = 10.5068(4) Å, b = 10.2225(5) Å, c = 14.0422(7) Å, and β = 104.489(3)°. The atomic arrangement can be described by layers built by all the components of the structure and centered by planes z = 1/4 and 3/4. The organic molecules form channels parallel to the c direction with dimensions of 4.163(1)Å and 5.148(4)Å. Thermal analysis shows that the anhydrous compound presents an irreversible weak phase transition. The IR study, based on theoretical analyses and on the literature data allows the interpretation of the IR spectrum. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Syntheses and crystal structures of two polymorphs of three‐dimensional silver (I) 5‐(3‐aminophenyl)tetrazolates

Two polymorphs of silver 5‐(3‐aminophenyl)tetrazolates – α‐ and β‐Ag(amphttz) have been obtained by the reaction of amphttzH with AgNO₃ in presence of ammonia either in ambient condition or under the hydrothermal condition, respectively (amphttzH = 5‐(3‐aminophenyl)tetrazole). Both of the two phases of Ag(amphttz) were characterized by elemental analyses, IR spectra and single‐crystal X‐ray diffraction. X‐ray analysis shows α‐, β‐phases crystallize in P ‐1 with a = 8.551 (2) Å, b = 8.720(2) Å, c = 11.173(2) Å, α = 98.15(3)°, β = 90.95(3)°, γ = 95.45(3)° and C 2/c with a = 13.542(3) Å, b = 10.135(2) Å, c = 12.610(3) Å, β = 113.58(3)°, respectively. The two polymorphs exhibit different 3D structures. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal and molecular structure of 1‐allyl‐5‐(4‐methylbenzoyl)‐4‐(4‐methylphenyl)pyrimidine‐2(1H)‐thione

The crystal structure of 1‐allyl‐5‐(4‐methylbenzoyl)‐4‐(4‐methylphenyl)pyrimidine‐2(1H)‐thione (C₂₂H₂₀N₂OS) has been determined from three dimensional single crystal X‐ray diffraction data. The title compound crystallizes in the monoclinic space group P 2₁/c, with a = 10.6674(13), b = 10.1077(7), c = 17.9467(19) Å, β = 98.460(9)°, V = 1914.0(3) ų, D_calc = 1.251 g cm^–3, Z = 4. In the title compound, the allyl group shows positional disorder. Molecules are linked by C‐H···O, C‐H···N and C‐H···S intermolecular interactions forming two‐dimensional network. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis,characterization and X‐ray crystal structure of guanidinuim (pyridine‐2,6‐dicarboxylato)(pyridine‐2,6‐monocarboxylato) zincate(II) mono pyridine‐2,6‐dicarboxylic acid tetrahydrate

A new complex of Zinc(II) and guanidinium pyridine–2,6–dicarboxylate proton transfer compound, (GnH)₂ (pydc), was synthesized and characterized using IR, ¹H NMR and ¹³C NMR spectroscopy and single crystal X–ray diffraction. The chemical formula and space group of the resulting complex is (GnH)[Zn(pydc)(pydcH)] · (pydcH₂) · 4H₂O, P 1 where the final R value is 0.0310 for 13287 reflections collected. The [Zn(pydc)(pydcH)]^– anions and the (GnH)⁺ counter‐cations form a three‐dimensional solid‐state structure by a variety of noncovalent interactions such as ion pairing, hydrogen bonding and π–π stacking which are going to be discussed. (© 2007 WILEY ‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis,crystal structure and third order nonlinear optical properties of bis(tetra‐n‐propylammonium) bis(2‐thioxo‐1,3‐dithiole‐4,5‐dithiolato)cuprate(II)

A novel bis (dmit) complex of copper (II), [(C₃H₇)₄N]₂[Cu(dmit)₂] ( 1 ), where dmit is 2‐thioxo‐1,3‐dithiole‐4,5‐dithiolate, was prepared and structurally characterized by X‐ray single crystal diffraction. The copper (II) atom is tetracoordinated by four dmit S atoms, forming a nearly square planar arrangement. The [Cu(dmit)₂]^2‐ anions and the [(C₃H₇)₄N]⁺ counter‐cations form a three‐dimensional solid‐state structure by C–H…S hydrogen bonds. The third‐order nonlinear optical properties of the complex were determined by picosecond Z‐scan technique at a wavelength of 1064 nm. The results indicate the compound exhibits reverse saturation absorption and self‐defocusing performance. The molecular second‐order hyperpolarizability γ is calculated to be as high as (1.8±0.2)×10^‐30 esu. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Study of the crystal shape and its influence on the anti‐tumor activity of tumor necrosis factor‐related apoptosis‐inducing ligand (Apo2L/TRAIL)

This paper describes a method about the crystal shape control improving the anti‐tumor activity of tumor necrosis factor‐related apoptosis‐inducing ligand (Apo2L/TRAIL) in a batch cooling suspension crystallization by selecting pH values as a controllable variable. Three shaped TRAIL crystals could be obtained under different pH conditions, among which the hexagonal plate crystals had the highest specific activities against tumor cell line. The relationship among pH values, trimer contents and the specific activities of crystals and the purified TRAIL solutions were investigated. The results showed that different trimer contents resulted from pH altering in crystals and protein solutions is a main reason for their different specific activities. The studies may supply a new method to improve the bioactivity of TRAIL agent during its production and storage. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis,characterization and crystal structure of a 3‐D supramolecular Cu/Mn complex with pydc

A supramolecular compound, {[CuMn(pydc)₂(H₂O)₅]·2H₂O} ( 1 ) (pydc = pyridine‐2,6‐dicarboxylate dianion), has been synthesized and characterized by single‐crystal X‐ray diffraction. Single‐crystal X‐ray analysis reveals that it crystallizes in the triclinic space group P‐1, a = 8.4763(17) Å, b = 9.7715(19) Å, c = 13.909(3) Å, α =101.234(3)°, β =102.520(3)°, γ= 97.375(4)°. Two mixed‐metal ions exhibit similar coordinated geometries with octahedron. 1 possesses a 3‐D unusual supramolecular network featuring 1D water tape. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal structure and properties of [Cu(sac)2(py)3], a new example of a mononuclear complex with both N‐ and O‐bonded saccharinate ligands

The crystal structure of the title complex has been determined by single X‐ray diffraction methods and refined to an R‐value of 0.0543. It crystallizes in the monoclinic P2₁/a space group with a = 21.1231(9), b = 9.4523(4), c = 16.1874(7) Å, β = 107.3706(3)° and Z = 4. The compound represents only the second known example of a simple mononuclear metal complex containing simultaneously N‐ and O‐bonded saccharinato ligands. Its infrared spectrum and thermal behavior are also briefly discussed.     

Synthesis and crystal structure of a new inorganic – organic complex: (4‐ClC7H6NH3)9[Nd(P6O18)2]·9H2O

Single crystals of (4‐ClC₇H₆NH₃)₉[Nd(P₆O₁₈)₂]·9H₂O were synthesized in aqueous solution. This compound crystallizes in a triclinic P1 unit‐cell, with a = 14.898(6), b = 18.049(7), c = 20.695(6)Å, α = 102.04(3), β = 100.49(3), γ = 98.82(3)°, V = 5245(4) ų and Z = 2. The crystal structure has been solved and refined to R = 0.043 (Rw = 0.061) for 20420 observed reflections. The atomic arrangement of the title compound can be described as infinite layers built by complex of Neodyme [Nd(P₆O₁₈)₂] and nine water molecules. The organic cations are located in the space delimited by the successive inorganic layers. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis and characterization of phosphates in the pseudo‐ternary melted systems Cs2O‐P2O5‐MIIO (MII – alkaline earth)

The crystallization of alkali‐earth phosphates in the melts of Cs₂O‐P₂O₅‐M^IIO (M^II – Ca, Sr, Ba) pseudo‐ternary systems have been investigated at various Cs/P molar ratios and at fixed value of M^II/P equal to 0.15. Type of the phosphate which crystallizes in melts depends on the Cs/P initial ratio. Crystallization fields of CsM^IIP₃O₉, M^II₂P₂O₇ and Cs₂M^IIP₂O₇ were briefly investigated and characterized. The new diphosphate Cs₂CaP₂O₇ has been obtained and investigated by the single crystal and powder X‐ray diffraction and FTIR‐ spectroscopy. It crystallizes in C 2/m space group, with the following parameters of the monoclinic cell: a = 10.261(2), b = 5.9316(12), c = 7.2404(14) Å, β = 118.54(3)°. The architecture of [CaP₂O₇]^2‐ anionic sublattice, which is built up from [CaO₆] octahedra and [P₂O₇] bitetrahedra, interlinked via the common oxygen vertices, gives rise to formation of hexagonal tunnels along crystallographic direction b, where caesium atoms are located. One of the most remarkable features of the structure is specific positional disorder of the diphosphate group, which is connected with the existence of two equiprobable half‐occupied sites of the bridging oxygen. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)