Sr3ZnPtO6 and Sr3CdPtO6

The flux synthesis of single crystals of the isostructural compounds tristrontium zinc platinum hexaoxide, Sr₃ZnPtO₆, and tristrontium cadmium platinum hexaoxide, Sr₃CdPtO₆, is reported. The compounds adopt the pseudo‐one‐dimensional rhombohedral K₄CdCl₆ structure type, and feature chains of face‐shared distorted ZnO₆ or CdO₆ trigonal prisms and PtO₆ octahedra, surrounded by columns of Sr²⁺ ions. All transition metals are located on the threefold axis of symmetry, while the Sr²⁺ cations lie on twofold axes.     

Ca4IrO6, Ca3MgIrO6 and Ca3ZnIrO6

Single crystals of tetracalcium iridium hexaoxide, Ca₄IrO₆, tricalcium magnesium iridium hexaoxide, Ca₃MgIrO₆, and tricalcium zinc iridium hexaoxide, Ca₃ZnIrO₆, were prepared via high-temperature flux growth and structurally characterized by single-crystal X-ray diffraction. The three compounds are isostructural and adopt the K₄CdCl₆ structure type, comprised of chains of alternating face-shared [CaO₆], [MgO₆] or [ZnO₆] trigonal prisms and [IrO₆] octahedra, surrounded by columns of Ca²⁺ ions.     

Contrast of Bonding and Characters for C6, B3N3, C6H6 and B3N3H6 Molecules

Through integrative consideration of NICS, MO, MOC and NBO, we precisely investigated delocalization and bonding characters of C₆, C₆H₆, B₃N₃ and B₃N₃H₆ molecules. Firstly, we originally discovered and testified that C₆ cluster was sp² hybridization. Negative NICS values in 0 and 1 Å indicated that C₆ had δ and Π aromaticity. Secondly, B₃N₃ with sp² hybridization had obvious δ aromaticity. Finally, WBI values approved that there were delocalization in C₆, C₆H₆ and B₃N₃ molecules, but B₃N₃H₆ structure did not have delocalization with the WBI 1.0. Moreover, total WBI values of carbon, boron and nitrogen atoms were four, three and three, respectively. Namely, the electrons of B₃N₃H₆ and B₃N₃ were localized in nitrogen atoms and they did not form delocalized bonding. In a word, bonding characters of carbon, boron and nitrogen atoms were dissimilar although the molecules composed of carbon, boron and nitrogen were regarded as isoelectronic structures.     

Kristallstrukturen von Na3TiCl6 und K3TiCl6

Ternary Halides of the Type A₃MX₆. IX Crystal Structures of Na₃TiCl₆ and K₃TiCl₆ Light yellow single crystals of Na₃TiCl₆ and K₃TiCl₆ are obtained from the binary components, TiCl₃ and NaCl and KCl, respectively, in 1 : 3 molar ratios. Na₃TiCl₆ crystallizes with the cryolite type of structure (monoclinic, P2₁/n, Z = 2, a = 668,02(8), b = 709,13(6), c = 981,38(12) pm, β = 90,31(2)°) while K₃TiCl₆ belongs to the K₃MoCl₆ type of structure (monoclinic, P2₁/c, Z = 4, a = 1261,6(2), b = 751,36(8), c = 1210,7(2) pm, β = 108,30(2)°).     

(m‐CH3C6H4NH3)6P6O18

In hexakis(m‐toluidinium) cyclo­hexaphosphate, 6C₇H₁₀N⁺·­P₆O₁₈^6?, the atomic arrangement is typical of a layer structure. Layers including the centrosymmetric P₆O₁₈ ring anions develop around the (100) planes at x = . The hydrogen‐bond distribution is described.     

Lanthanide Nitrido Borates with Six-Membered B3N6 Rings: Ln3B3N6

Metal compounds with heteroatomic ring systems of main group elements are a domain of coordination chemistry. However, lanthanide nitrido borates Ln₃B₃N₆ (Ln=La or Ce; see structure) are synthesized by the reaction of hexagonal boron nitride with LnN. The compounds contain the six-membered B₃N₆ ring, which can be seen as a fragment from one layer of the hexagonal BN structure.     

Partialsynthese von 6-epi-gibberellin-A3

$\text{2}$ is silylated, enolised with KH and converted by the addition of acid to a mixture of epimeric aldehydes $\text{2}$ and $\text{3}$. Subsequent acetylation, oxydation and deacetylation of $\text{3}$ affords 6-Epi-gibberellin-A₃ ($\text{6}$).     

C3N6H6(H3BO3)2的合成及晶体结构

以三聚氰胺和硼酸为原料在水溶液中反应合成出了一种新的BCN化合物先驱体C3N6H6(H3BO3)2。XRD表征结果表明三聚氰胺和硼酸的最佳配比为1∶3(物质的量比)。用单晶X-射线衍射分析法测定了该化合物的晶体结构。该化合物属单斜晶系,空间群为P21/C,晶胞参数为a=0.3597(7)nm,b=2.0105(4)nm,c=1.4112(3)nm,α=90,°β=92.07(3),°γ=90,°V=1.0199(3)nm3,Z=4,D c=1.627g.cm-3,μ(MoKα)=0.144mm-1,F(000)=520。晶体结构经全矩阵最小二乘法修正,最终可靠因子R1=0.0519,wR2=0.1361。该化合物是由C3N6H6分子和H3BO3分子通过氢键加合组装形成的三维超分子结构化合物。     

Preparation and fungitoxicity of 3-bromo-6-chloro- and 6-bromo-3-chloro-8-quinolinols

Summary 3-Bromo-6-chloro- and 6-bromo-3-chloro-8-nitro, -8-amino-, and -8-hydroxyquinolines along with 3-bromo- and 3-chloroquinolin-6,8-diols were prepared and tested for antifungal activity against six fungi (Aspergillus niger, A. oryzae, Myrothecium verrucaria, Trichoderma viride, Mucor cirinelloides, Trichophyton mentagrophytes) inSabouraud dextrose broth. Compounds with chlorine in the 3 position were generally more fungitoxic than the corresponding analogues with bromine. 6-Bromo-3-chloro-8-quinolinol inhibited four fungi at levels below 1 µg/ml andA. niger andM. cirinelloides at 2 µg/ml each.

---

Synthese und Fungitoxizität von 3-Brom-6-chlor- und 6-Brom-3-chlor-8-chinolinolen

Zusammenfassung 3-Brom-6-chlor- und 6-Brom-3-chlor-8-nitro-, -8-amino- und -8-hydroxychinoline sowie 3-Brom- und 3-Chlorchinolin-6,8-diole wurden hergestellt und gegen sechs Pilzstämme (Aspergillus niger, A. oryzae, Myrothecium verrucaria, Trichoderma viride, Mucor cirinelloides, Trichophyton mentagrophytes) inSabouraud-Dextrosenährmedium auf lhre fungizide Aktivität untersucht. Verbindungen mit Chlor in Position 3 sind durchwegs fungitoxischer als die entsprechenden Bromanalogen. 6-Brom-3-chlor-8-chinolinol hemmt das Wachstum von vier Pilzen bei Konzentrationen unter 1 µg/ml und das vonA. niger undM. cirinelloides bei einer Konzentration von jeweils 2 µg/ml.

     

(3E)-胆甾-4-烯-3,6-二酮-3-肟和(6E)-胆甾-4-烯-3,6-二酮-6-肟的1D-NMR谱学特征及构象分析

采用1H和13C NMR对海绵中存在的同分异构体(6E)-胆甾-4-烯-3,6-二酮-6-肟(1)和(3E)-胆甾-4-烯-3,6-二酮-3-肟(2)进行结构分析,表征了它们在1H和13C NMR波谱中H2～H7及C2～C7之问的谱学差别,并对造成这种差别的原因进行了分析,同时对这两种位置异构体进行了构象分析和结构区分.     

The carbides Gd3Mn2C6 and Tb3Mn2C6

Crystals of the title compounds were obtained by arc-melting cold-pressed pellets of the elemental components, followed by annealing the reaction products in an argon atmosphere slightly below the melting point. The crystal structures of these isotypic, hexagonal carbides (P6₃/m, Z=2) were determined from single-crystal X-ray data; Gd₃Mn₂C₆: a=815.0(2) pm, c=504.93(9) pm, R=0.012 for 526 structure factors and 18 variable parameters; Tb₃Mn₂C₆: a=810.5(2) pm, c=500.5(2) pm, R=0.025 (225 F′s, 18 variables). The carbon atoms form pairs with C—C bond distances corresponding to double bonds. The three-dimensional, polyanionic managanese carbon network contains relatively large trigonal-bipyramidal voids formed by three lanthanoid and two manganese atoms. The rationalization of chemical bonding on the basis of the 18-electron rule suggests that these voids are filled by nonbonding electrons of the adjacent manganese atoms.     

Zur Stereoanalyse von Diastereomeren 5-C-Ethoxycarbonyl-methylen-hexofuranurono-6, 3-lactonen und-3, 6-Anhydrofuranosen

The stereochemistry of the branched C-ethoxycarbonyl-methy.lene derivatives 1a, 1b, 2a, and 2b was evaluated by analysis of their ¹H- and ¹³C-NMR shift data, unequivocally supported by NOE-effects clearly discriminating diastereomers. The X-ray-analysis of isomer 2a confirmed the NMR-data and provided the picture of its detailed structure.     

Rubidium metaborate,Rb3B3O6

Rubidium metaborate, Rb₃B₃O₆, was obtained by the reaction of Rb₂CO₃ and BN using a radiofrequency furnace at a maximum reaction temperature of 1173 K. The crystal structure has been determined by single‐crystal X‐ray diffraction. The space group is , with all atoms positioned on a twofold axis (Wyckoff site 18e). The ionic compound is isotypic with Na₃B₃O₆, K₃B₃O₆ and Cs₃B₃O₆.     

γ-Irradiation of Nylon 6

Viscosity, Infra-red, NMR spectral measurement technique, density measurement, and electrical conductivity were used to study the changes that occured during γ-radiolysis of Nylon 6. It was observed that it undergoes chain scission and crosslinking, but chain scission predominates over crosslinking in air irradiation. From melting temperature, density measurement, and the use of the Flory equation the enthalpy of fusion of Nylon 6 is 11.86 and 13.84 kJ/mol in an inert atmosphere and in air irradiation, respectively. The indirect effective band gap decreases and electrical conductivity increases when Nylon 6 is irradiated with γ-rays.