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1.
Summary Crystals of (NH3OH)3GaF6 have been isolated from aqueous solution. The compound crystallizes triclinic, with cell parametersa=6.539(5) Å,b=6.924(5) Å,c=9.403(1) Å, =87.01(9)°, =83.98(8)°, =70.28(8)°. The thermal decomposition was studied by TG and DSC analysis.
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2.
Summary 2,3-Dihydro-3-oxo-benzo[b]thiophen-1,1-dioxide (1) reacts as CH-acidic component with amidines of orthoesters and anilines resp. to give the anilinomethylene derivates3, 4, and5. With triethyl orthoformiate the hydroxymethylene-compound7 is obtained. Anilino- and phenylhydrazino derivates8 and9 prove the carbonyl activity of1, azo-coupling leads to10, whereas treatment of1 with sulfur and malononitrile yields the benzo[b]thieno[2,3-d]thiophenes11. Introduction of substituents with active NH-functions in position 2 of the dicyanomethylene-product2, such as azocoupling, reaction with phenyl isocyanate and formation of enamines, leads to ring closure reactions between a nitrile and the NH-group. Thereby the phenyl-benzo[4,5]thieno[2,3-c]pyridazines12, the phenyl-1H-benzo[4,5]thieno[2,3-c]pyridines13 and the phenylamino-benzo[4,5]thieno[2,3-c]pyridines14 are obtained.13C and15N-NMR spectroscopy was used as proof of the ring closure reactions.
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3.
Investigations in the system Sb-Se-NaOH-H2O, hydrothermal conditions, yielded crystals of the compound Na3SbSe3·3Sb2O3·0,5Sb(OH)3. The structure of this compound (a=14.40 Å,c=5.568 Å; space group P 63-C 6 6 ;Z=2) was determined from 985 independent X-ray intensities — collected on an automaticWeissenberg type diffractometer — by thePatterson method and refined by the least squares method toR=8.3% (with -weighting 5.9%). The structure consists of SbO3 pyramids which are connected via common oxygen corners to tubes parallel [001]. These tubes and SbSe3 pyramids are combined by Na atoms to a framework. The Sb(OH)3 groups are statistically located within the channels of the tubes.
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4.
Summary Hydroxylammonium fluorozirconates have been investigated. Two new microcristalline phases have been isolated from aqueous solutions: (NH3OH)2ZrF6 (1) and (NH3OH)3ZrF7 (2). The crystals were prepared by slow evaporation of the solution of NH2OH, Zr, and HF. Different compositions of the crystals were achieved by varying the molar ratios of the components. They were characterized by thermal analysis, vibrational spectroscopy, and structure (single crystal x-ray methods). (NH3OH)2ZrF6 (1) crystallizes triclinic, P (No.: 2),a=7.400(2),b=7.609(2),c=7.887(2) Å, =57.29(3)°, =62.16(3)°, =67.83(2)°. (NH3OH)3ZrF7 (2) crystallizes triclinic, P (No.: 2),a=7.128(1),b=7.989(1),c=8.888(1) Å, =109.72(1)°, =91.01(1)°, =104.27(1)°.
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5.
Crystals of PbCu3(OH)(NO3)(SeO3)3·1/2H2O [a=7.761(3)Å,b=9.478(4)Å,c=9.514(4)Å, =66.94(2)°, =69.83(2)°, =81.83(2)°, space group P ,Z=2] and Pb2Cu3O2(NO3)2(SeO3)2 [a=5.884(2)Å,b=12.186(3)Å,c=19.371(4)Å, space group Cmc21,Z=4] were synthesized under hydrothermal conditions. Their crystal structures were refined with three-dimensional X-ray data toR w=0.033 resp. 0.055. In PbCu3(OH)(NO3)(SeO3)3·1/2H2O the Cu atoms are [4+1] and [4+2] coordinated and via SeO3 groups a three-dimensional atomic arrangement is built up. In Pb2Cu3O2(NO3)2(SeO3)2 there are sheets, which are connected only via Pb-O bonds ranging from 2.98 Å to 3.16 Å.
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6.
The monoclinic compound PbCuAs2O7 [a=5.553 (1),b=8.404 (1),c=13.011 (2) Å, =91.61 (2)° space group P21/n-C 2h 5 ;Z=4] was synthesized under hydrothermal conditions. The structure was solved by direct methods and was refined to anR value of 3.6%. The Pb atom is irregularly eight coordinated by O atoms, and the Cu atom tetragonal pyramidal [4+1] coordinated by O atoms. Each two AsO4 tetrahedra share a common O atom corner building up As2O7 groups. These groups are connected with the CuO4 polyhedra to sheets parallel (101). These sheets are combined by the PbO8 polyhedra to a framework.
Herrn Prof. Dr.K. Komarek zum 60. Geburtstag gewidmet.  相似文献   

7.
Summary The microcristalline phase (NH3OH)2TiF6 has been isolated from aqueous solution. It crystallizes in the tetragonal system with cell parameters:a=9.654±0.005 Å,c=11.546±0.010 Å. The hydroxylammonium fluorotitanate was characterized by vibrational spectroscopy and its thermal decomposition studied by DSC and TG analysis.
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8.
A new compound, Pb2BO3F, has been grown by high temperature solution method from the PbO–PbF2–B2O3 system for the first time. The crystal structure of this compound has been identified by single crystal X-ray diffraction analysis. It crystallizes in the hexagonal system, space group P63/m (No. 176) with unit-cell parameters a=7.2460(3) Å, c=14.5521(17) Å, Z=6, V=661.69(9) Å3. Its structure was solved by the direct methods and refined to R1=0.0163 and wR2=0.0367. The structure of Pb2BO3F consists of the distorted PbO3F2 groups and BO3 triangles, which are all symmetric with each other in the gestalt structure to the extent that the Pb2BO3F compound crystallizes in the symmetric space group. The powder X-ray diffraction pattern of the Pb2BO3F has been measured. The BO3 functional groups presented in the sample were identified by FTIR spectrum. The DTA curve of Pb2BO3F suggests that Pb2BO3F melts congruently at 448 °C.  相似文献   

9.
An efficient synthetic method of poly-substituted pyridines was developed. Various poly-substituted pyridines were prepared from the combination of Baylis-Hillman adducts (3 carbons), activated methylene compounds (2 carbons) and ammonium acetate (1 nitrogen) via [3+2+1] annulation protocol in good yields, regioselectively.  相似文献   

10.
The methyl ether of calix[8]arene crystallizes from CDCl3 with two molecules of the solvent per molecule of host. An X-ray structural investigation has shown that the CDCl3 guests exist within the calixarene framework. The complex resides on a crystallographic center of inversion, and the cavity is roughly circular in projection as measured by the distance between centroids of aromatic rings related by the center: 14.5, 13.9, 10.1, and 11.2 Å. Six of the oxygen atoms are found on the inside and two on the outside. Crystals belong to the triclinic space group witha=11.741(9),b=11.810(9),c=12.484(8) Å, =94.74(8), =104.41(8), =111.30(9)°, andD c =1.31 g cm–3 forZ=1. Refinement led to a finalR value of 0.086 for 949 observed reflections. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82038 (10 pages).  相似文献   

11.
Summary Two microcristalline phases have been isolated from aqueous solutions: (NH3OH)2AlF5(A) and (NH3OH)AlF4·H2O(B). They crystallize in the orthorhombic system with cell parameters for A:a=6.475 (3) Å,b=7.295 (3) Å,c=10.827 (5) Å, and for B:a=7.003 (3) Å,b=8.489 (4) Å,c=10.745 (5) Å. The Hydroxylammonium-aluminates were characterized by vibrational spectroscopy and their thermal decomposition studied by DSC and TG analysis.
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12.
Summary The behaviour of amidoximes3 and4 under cyclization conditions is reported: Reaction with carbonyldiimidazole yields oxadiazolobenzoxazine11 and oxadiazolobenzothiazine12, respectively.
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13.
Summary The crystal structure of synthetic Cu3SeO4(OH)4 was determined by single crystal X-ray methods:a=8.382 (2) Å,b=6.087 (1) Å,c=12.285 (2) Å,V=626.8 Å3,Z=4, space group Pnma,R=0.026,R w =0.021 for 1255 independent reflections (sin / 0.8 Å–1). The crystal structure is isotypic to that of the mineral antlerite, Cu3SO4(OH)4. The copper atoms are Jahn-Teller distorted with Cu[4+2]O6 polyhedra forming triple chains along [010]. These chains are linked via SeO4 tetrahedra and weak hydrogen bonds to a framework structure.
Die Kristallstruktur von synthetischem Cu3SeO4(OH)4
Zusammenfassung Die Kristallstruktur von synthetischem Cu3SeO4(OH)4 wurde mittels Einkristall-Röntgenmethoden ermittelt:a=8.382 (2) Å,b=6.087 (1) Å,c=12.285 (2) Å,V=626.8 Å3,Z=4, Raumgruppe Pnma,R=0.026,R w =0.021 für 1255 unabhängige Reflexe (sin / 0.8 Å–1). Die Kristallstruktur ist isotyp mit der des Minerals Antlerit, Cu3SO4(OH)4. Die Kupferatome sind Jahn-Teller-verzerrt, die Cu[4+2]O6 Polyeder bilden Dreierketten entlang [010]. Diese Ketten sind über SeO4-Tetraeder und schwache Wasserstoffbrücken zu einer Gerüststruktur verbunden.
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14.
以氨水和碳酸铵为沉淀剂制备氧化铝的对比研究   总被引:3,自引:0,他引:3  
γ-Al2O3,是一种常用的催化剂载体,它具有比表面大和价廉易得等优点。但对于很多高温反应体系,如汽车尾气催化净化,其热稳定性在很大程度上影响了汽车尾气净化催化剂的活性和稳定性,因此提高γ-Al2O3的高温热稳定性对保持汽车尾气净化催化剂的反应活性、延长催化剂的使用寿命非常重要。  相似文献   

15.
ABSTRACT

An efficient and green approach for synthesizing chromeno[2,3-b]pyridine derivatives through one-pot three-component reactions of salicylaldehydes, thiols, and malononitrile has been developed by Fe3O4@SiO2–NH2 nanocatalyst in aqueous ethanol media under re?ux conditions. The present procedure provides several advantages such as environmentally benign, straightforward, excellent yields, short reaction times, cost-effective, good recyclability, little catalyst loading, and facile catalyst separation for the preparation of chromeno[2,3-b]pyridines as important privileged medicinal scaffold. In addition, aminopropyl-coated Fe3O4@SiO2 nanoparticles were fully characterized by scanning electron microscopy, X-ray diffraction, energy dispersive analysis of X-ray, vibrating sample magnetometer, and FT-IR analysis.  相似文献   

16.
Summary The ozonolysis ofendo-2-acetyl-3,3-dimethylbicyclo[2.2.1]hept-5-ene (endo-1) and itsexo-epimer (exo-1) is described. The reaction products, after reductive work up as well as after oxidative work up, are characterized. The first procedure furnished the corresponding cyclopentane derivatives in good yield, namely 1,1-dimethyl-2-(1-hydroxyethyl)-3,5-bis-hydroxymethyl cyclopentane (2) as a cristalline compound fromendo-1, the epimeric10 as an oil fromexo-1. The oxidative work up furnished in both cases via keto-enol-tautomerism the same acid, 4-acetyl-5,5-dimethyl-1,3-cyclopentane dicarboxylic acid, characterized as its methyl ester. Selective oxidation of the secondary hydroxyl group in2 lead to the novel, tricyclic, even acid stable ketal17, with very interesting olfactory properties.
Herrn Prof. Dr. Ulrich Schmidt mit den besten Wünschen zum 70. Geburtstag gewidmet  相似文献   

17.
Crystals of K2Co3(OH)2(SO4)3·2H2O were synthesized under hydrothermal conditions. The crystal structure [a=17.945 (4) Å,b=7.557 (2) Å,c=9.760 (3) Å, space group Cmc21,Z=4] was determined by direct methods and refined with single crystal X-ray data. The H atoms were located byFourier syntheses. Their structural parameters were refined, too. The finalR-values areR=0.025 andR w =0.028 (w=1/) for 612 reflections withF 0>3 (F 0). Both Co(II) atoms are octahedral six coordinated and form zigzag chains running parallel [001]. These chains are connected via sulfate groups to built up sheets parallel (100). The KO9 polyhedron and one of the four hydrogen bonds link these sheets.
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18.
Reaction of the methyl ether of calix[8]arene with AlMe3 yields [calix[8]arene methyl ether] [AlMe3]6·2 toluene,1, while that ofp-tert-butylcalix[8]arene gives [p-tert-butylcalix[8]arene methyl ether] [AlMe3]6·4 benzene,2. Both compounds1 and2 fail to react with alkali metal salts, MX. In1, the absence of a butylpara-substituent affords greater flexibility than is the case for thetert-butyl compound2. Thus, all six of the AlMe3 groups are located on the outside of the macrocyclic ring (in projection) in1, but two AlMe3 units are found on the inside in2. Colorless, air-sensitive crystals of1 belong to the triclinic space group witha=13.690(8),b=14.317(4),c=14.738(6) Å, =76.11(3), =62.36(4), =82.41(4)o, andD c =1.06 g cm–3 forZ=1. Refinement led toR=0.101 for 1154 observed reflections.2 crystallizes in with =12.400(6),b=16.229(8),c=19.251(5) Å, =96.17(3), =107.25(3), =101.54(3)o, andD c =1.01 g cm–3 forZ=1. Refinement of2 gaveR=0.128 for 4351 observed reflections. The macrocyclic array in both1 and2 lies about a crystallographic center of inversion. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82049 (48 pages).  相似文献   

19.
使用四乙基氢氧化铵为有机模板剂,以低硅铝比(nSiO2/nAl2O3)的Y分子筛为铝源,通过转晶法制备结晶度良好的SSZ?13沸石分子筛。从凝胶配比方面考察了不同原料组成对分子筛合成的影响,并通过X射线衍射(XRD)、扫描电子显微镜(SEM)及电感耦合等离子体(ICP)表征水热反应过程中的物相、形貌、硅铝比等变化,揭示分子筛合成过程。氨选择性催化还原(NH3?SCR)反应显示该分子筛具有优异的催化活性,为其工业上的广泛应用提供了可能性。  相似文献   

20.
The crystal structure of the new phase Cu7(OH)6(TeO3)2(SO4)2 [a=7.389 (1),b=7.638 (1),c=7.662 (2) Å, =75.17 (1), =75.90 (1), =84.19 (1)°;Z=1] was determined by direct methods andFourier summations from X-ray intensities, and was refined in space group P -C i 1 toR=0.039. As usual, the Cu(II) atoms are coordinated to four O atoms forming approximately a square with average Cu-O=1.96 (3) Å; one or two more distant O neighbours complete the coordination. The shape of the TeO3 group is a rather clear-cut trigonal pyramid. A disorder was found for the SO4 tetrahedra. The compound was synthesized under hydrothermal conditions [500 (10) K, saturation vapour pressure].
Herrn Prof. Dr.K. Komarek zum 60. Geburtstag gewidmet.  相似文献   

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