ChemInform Abstract: Crystal Growth,Crystal Structure of New Polymorphic Modification, β‐Bi2B8O15 and Thermal Expansion of α‐Bi2B8O15.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

(Carbonyl)Iron‐Selenolates: New Synthetic Methods and Reactions with Electrophiles. Crystal Structures of [(CO)6Fe2(μ‐SeR)2]; R = Me3SiCH2 and p‐O2NC6H4CH2, {(CO)6Fe2[μ‐η2‐Se,Se′‐o‐(SeCH2C6H4CH2Se)]}, and [(CO)6Fe2(μ‐SeFe(CO)2cp)2]

The reactions of Fe(CO)₅ or Fe₃(CO)₁₂ with NaBEt₃H or KB[CH(CH₃)C₂H₅]₃H, respectively and treatment of the resulting carbonylates M₂Fe(CO)₄, M = Na, K with elemental selenium in appropriate ratios lead to the formation of M₂[Fe₂(CO)₆(μ‐Se)₂]. Subsequent reactions with organo halides or the complex fragment cpFe(CO)₂⁺, cp = η⁵‐C₅H₅ afforded the selenolato complexes [Fe₂(CO)₆(μ‐SeR)₂], R = CH₂SiMe₃ ( 1 ), CH₂Ph ( 2 ), p‐CH₂C₆H₄NO₂ ( 3 ), o‐CH₂C₆H₄CH₂ ( 4 ) and cpFe(CO)₂⁺ ( 5 ) in moderate to good yields. A similar reaction employing Ru₃(CO)₁₂, Se and p‐O₂NC₆H₄CH₂Br leads to the formation of the corresponding organic diselenide. The X‐ray structures of 1 , 3 , 4 and 5 were determined and revealed butterfly structures of the Fe₂Se₂ cores. The substituents in 1 , 3  and 5 adopt different conformations depending on their steric demand. In 4 , the conformation is fixed because of the chelate effect of the ligand. The Fe–Se bond lengths lie in the range 235 to 240 pm, with corresponding Fe–Fe bond lengths of 254 to 256 pm. The ⁷⁷Se NMR data of the new complexes are discussed and compared with the corresponding data of related complexes.     

Synthesis,Crystal Structure and Hydrolysis of a Novel Anhydrogalactosucrose: 2′‐Methoxyl‐O‐1′,4′:3′,6′‐dianhydro‐β‐D‐fructofuranosyl 3,6‐anhydro‐4‐chloro‐4‐deoxy‐α‐D‐galactopyranoside

A novel anhydrogalactosucrose derivative 2′‐methoxyl‐O‐1′,4′:3′,6′‐dianhydro‐β‐D‐fructofuranosyl 3,6‐anhydro‐4‐chloro‐4‐deoxy‐α‐D‐galactopyranoside ( 4 ) was prepared from 3,6:1′,4′:3′,6′‐trianhydro‐4‐chloro‐4‐deoxy‐galactosucrose ( 3 ) via a facile method and characterized by ¹H NMR, ¹³C NMR and 2D NMR spectra. The single crystal X‐ray diffraction analysis shows that the title molecule forms a two thee‐dimensional network structure by two kinds of hydrogen bond interactions [O(2) H(2)···O(7), O(5) H(5)···O(8)]. Its stability was investigated by acid hydrolysis reaction treated with sulfuric acid, together with the formation of 1,6‐Di‐O‐methoxy‐4‐chloro‐4‐deoxy‐β‐D‐galactopyranose ( 5 ) and 2,2‐Di‐C‐methoxy‐1,4:3,6‐dianhydromannitol ( 6 ). According to the result, the relative stability of the ether bonds in the structure is in the order: C(1) O C(5)≈C(3′) O C(6′)≈C(1′) O C(4′)>C(3) O C(6)≈C(1) O C(2′)>C(2′) O C(5′).     

ChemInform Abstract: Crystal Structures of α-(Co(II)W12O40)6- and Its Heteropoly Blue 2e Reduction Product, α-(Co(II)W12O40)8-. Structural,Electronic, and Chemical Consequences of Electron Delocalization in a Multiatom Mixed-Valence System.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

Crystal structure of the thortveitite‐related M phase, (MnxZn1–x)2V2O7 (0.75 < x < 0.913): a combined synchrotron powder and single‐crystal X‐ray study

The determination of the crystal structure of the M phase, (Mn_xZn_1–x)₂V₂O₇ (0.75 < x < 0.913), in the pseudobinary Mn₂V₂O₇–Zn₂V₂O₇ system for x ≃ 0.8 shows that the previously published triclinic unit‐cell parameters for this thortveitite‐related phase do not describe a true lattice for this phase. Instead, single‐crystal X‐ray data and Rietveld refinement of synchrotron X‐ray powder data show that the M phase has a different triclinic structure in the space group P with Z = 2. As prior work has suggested, the crystal structure can be described as a distorted version of the thortveitite crystal structure of β‐Mn₂V₂O₇. A twofold superstructure in diffraction patterns of crystals of the M phase used for single‐crystal X‐ray diffraction work arises from twinning by reticular pseudomerohedry. This superstructure can be described as a commensurate modulation of a pseudo‐monoclinic basis structure closely related to the crystal structure of β‐Mn₂V₂O₇. In comparison with the distortions introduced when β‐Mn₂V₂O₇ transforms at low temperature to α‐Mn₂V₂O₇, the distortions which give rise to the M phase from the β‐Mn₂V₂O₇ prototype are noticeably less pronounced.     

Synthesis,structure and properties of a new three‐dimensional interpenetrated metal–organic framework with 3,3′‐azodibenzoic acid (H2azdc) and 1,4‐bis(1H‐imidazol‐1‐yl)butane (bimb): {[Cd(azdc)(bimb)2]·H2O}n

A new three‐dimensional interpenetrated Cd^II–organic framework based on 3,3′‐azodibenzoic acid [3,3′‐(diazenediyl)dibenzoic acid, H₂azdc] and the auxiliary flexible ligand 1,4‐bis(1H‐imidazol‐1‐yl)butane (bimb), namely poly[[bis[μ₂‐1,4‐bis(1H‐imidazol‐1‐yl)butane‐κ²N³:N^3′][μ₂‐3,3′‐(diazenediyl)dibenzoato‐κ²O:O′]cadmium(II)] monohydrate], {[Cd(C₁₄H₈N₂O₄)(C₁₀H₁₄N₂)₂]·H₂O}_n, (1), was obtained by a typical solution reaction in mixed solvents (water and N,N′‐dimethylformamide). Each Cd^II centre is six‐coordinated by two O atoms of bis‐monodentate bridging carboxylate groups from two azdc²⁻ ligands and by four N atoms from four bimb ligands, forming an octahedral coordination environment. The Cd^II ions are connected by the bimb ligands, resulting in two‐dimensional (4,4) layers, which are further pillared by the azdc²⁻ ligands, affording a threefold interpenetrated three‐dimensional α‐Po topological framework with the Schläfli symbol 4¹²6³. The thermal stability and solid‐state fluorescence properties of (1) have been investigated.     

A novel one‐dimensional metal–organic framework with a μ‐cyanido‐argentate group: catena‐poly[[(5,5′‐dimethyl‐2,2′‐bipyridyl‐κ2N,N′)silver(I)]‐μ‐cyanido‐κ2N:C]

The design and synthesis of metal coordination and supramolecular frameworks containing N‐donor ligands and dicyanidoargentate units is of interest due to their potential applications in the fields of molecular magnetism, catalysis, nonlinear optics and luminescence. In the design and synthesis of extended frameworks, supramolecular interactions, such as hydrogen bonding, π–π stacking and van der Waals interactions, have been exploited for molecular recognition associated with biological activity and for the engineering of molecular solids.The title compound, [Ag(CN)(C₁₂H₁₂N₂)]_n, crystallizes with the Ag^I cation on a twofold axis, half a cyanide ligand disordered about a centre of inversion and half a twofold‐symmetric 5,5′‐dimethyl‐2,2′‐bipyridine (5,5′‐dmbpy) ligand in the asymmetric unit. Each Ag^I cation exhibits a distorted tetrahedral geometry; the coordination environment comprises one C(N) atom and one N(C) atom from substitutionally disordered cyanide bridging ligands, and two N atoms from a bidentate chelating 5,5′‐dmbpy ligand. The cyanide ligand links adjacent Ag^I cations to generate a one‐dimensional zigzag chain. These chains are linked together via weak nonclassical intermolecular interactions, generating a two‐dimensional supramolecular network.     

Weak Noncovalent Interactions in Three Closely Related Adamantane-Linked 1,2,4-Triazole N-Mannich Bases: Insights from Energy Frameworks,Hirshfeld Surface Analysis,In Silico 11β-HSD1 Molecular Docking and ADMET Prediction

Structural analysis and docking studies of three adamantane-linked 1,2,4-triazole N-Mannich bases (1–3) are presented. Compounds 1, 2 and 3 crystallized in the monoclinic P2₁/c, P2₁ and P2₁/n space groups, respectively. Crystal packing of 1 was stabilized by intermolecular C-H⋯O interactions, whereas compounds 2 and 3 were stabilized through intermolecular C-H⋯N, C-H⋯S and C-H⋯π interactions. The energy frameworks for crystal structures of 1–3 were described. The substituent effect on the intermolecular interactions and their contributions were described on the basis of Hirshfeld surface analyses. The 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibition potential, pharmacokinetic and toxicity profiles of compounds 1–3 were determined using in silico techniques. Molecular docking of the compounds into the 11β-HSD1 active site showed comparable binding affinity scores (−7.50 to −8.92 kcal/mol) to the 11β-HSD1 co-crystallized ligand 4YQ (−8.48 kcal/mol, 11β-HSD1 IC₅₀ = 9.9 nM). The compounds interacted with key active site residues, namely Ser170 and Tyr183, via strong hydrogen bond interactions. The predicted pharmacokinetic and toxicity profiles of the compounds were assessed, and were found to exhibit excellent ADMET potential.     

Single crystal X-ray diffraction study of a mixed-valence gold compound, Cs2AuAuCl6 under high pressures up to 18 GPa: Pressure-induced phase transition coupled with gold valence transition

We performed the single-crystal X-ray diffraction study of a perovskite-type gold mixed-valence compound, Cs₂Au^IAu^IIICl₆, under high pressures up to 18 GPa by using a diamond-anvil-cell with helium gas as an ideal hydrostatic pressure-transmitting medium. The lattice parameters and the variable atomic positional parameters were obtained with reasonable accuracy at various pressures. A structural phase transition at ca. 12.5 GPa from I4/mmm to Pm3m was found. The lattice parameters a₀ and c₀, denoted in the tetragonal cell setting, result in the relationship 2^1/2a₀=c₀, and the superstructure reflections h k l (l is odd), caused by the shift of the Cl ions from the midpoint of the Au ions, disappeared at pressures above the phase transition. Both elongated [Au^IIICl₆] and compressed [Au^ICl₆] octahedra in the low-pressure phase smoothly approach regular octahedra with increasing pressure. Above the structural phase transition at 12.5 GPa, all the [AuCl₆] octahedra are crystallographically equivalent, which shows that the tetragonal-to-cubic phase transition accompanies the valence transition from the Au^I/Au^III mixed-valence state to the Au^II single-valence state.     

1-Ethylthio-2-[2-thienyltelluro]ethane (L) a new (Te, S) ligand: Synthesis and complexation with Ag(I), Cu(I), Pd(II) and Pt(II) – Single crystal structures of [PdCl2(L)] and bis(thienyl) tellurium(IV) chloride

Lithium 2-thienyltellurolate, generated from 2-thienyl lithium, reacts at −78 °C in THF with chloroethyl ethyl sulfide to give a (Te, S) ligand 1-ethylthio-2-[2-thienyltelluro]ethane (L) as a red oil. The complexes [PdCl₂(L)] (1), [PtCl₂(L)] (2), [Ag(L)₂][ClO₄] (3) and [CuBr(L)]₂ (4) were synthesized. The complex [HgCl₂(L)] on crystallization decomposed giving Th₂TeCl₂ (5) [where Th = 2-thienyl], which was characterized by X-ray diffraction on its single crystals. The ligand L and complexes 1–4 exhibit proton and carbon-13 NMR spectra, which are characteristic. The coordination through Te in 1–4 is indicated by downfield coordination shifts in the position of the TeCH₂ signal of L. Complex 1 was characterized by X-ray diffraction on its single crystals. The geometry around Pd is square planar. The Pd–Te, Pd–S and Pd–Cl bond lengths are 2.5040(4), 2.273(1) and 2.322(1)/2.380(1) Å, respectively. There are intermolecular interactions between Te (coordinated to Pd) and Cl, and sulfur and Cl. The Te–Cl and S–Cl distances, 3.401 and 3.488 Å, respectively, are shorter than the sum of the van der Waal’s radii (3.81 and 3.55 Å, respectively). The Pd–Pd distance between the two molecules is 3.4156(6) Å, greater than the sum of van der Waal’s radii (3.26 Å). The structure of 5 is typical of that of a tellurium(IV) compound (saw-horse type). The two Te–Cl bond lengths are identical, 2.480(1) Å. The geometry around Te in 5 can be best described as pseudo tetrahedral (trigonal bipyramidal with a lone pair on one corner of the triangle).