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  • Articles: DFG German National Licenses  (16)
  • crystal structure  (13)
  • Organic Chemistry  (3)
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 77 (1994), S. 1611-1615 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Formation, X-Ray Crystal Structure, and Absolute Configuration of (-)-N-(Chloromethyl)galanthaminium ChlorideThe acetylcholinesterase inhibitor galanthamine (1), main alkaloid of several Narcissus species, readily forms a quaternary ammonium salt by reaction with the solvent CH2Cl2. The structure and absolute configuration of (-)-N-(chloromethyl)galanthaminium chloride (2) were determined by X-ray diffraction (R = 0.075 for 2775 observed independent reflexions) and NMR spectroscopy. The tetragonal crystals (space group P43) contain two crystallographically independent cations which do not differ significantly from one another. The CH2Cl group is attached to the quaternary N-atom in stereospecific (R)-configuration. In the crystal, the configurational position of the Me group at the N-atom of 2 differs from that of the crystalline free base 1. Hydrogen bonding is observed from the OH group at C(3) of 2 to the Cl- anion or to the Cl-atom of an adjacent cation.
    Additional Material: 2 Ill.
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1984 (1984), S. 306-318 
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Intramoleclar Addition of Carbanions to AnthraquinonesThe intramolecular Michael addition of the carbanions derived from the β-keto diesters 15a and 15b yields the naphthacenequinones 20a and 20b. In contrast, the similar dimethyl ether 11 cyclizes to give the benzo[α]anthracenequinone 17. The hydroquinone of 1,8-dihydroxyanthraquinone (5a) reacts with acrylate to yield the unusual anthrone derivatives 12b and 12c.
    Notes: Die intramolekulare Michael-Addition der Carbanionen, die sich von den β-Ketodiestern 15a und 15b ableiten, liefert die Naphthacenchinone 20a und 20b. Dagegen cyclisiert der Dimethylether 11 zum Benzo[α]anthracenchinon 17. Das Hydrochinon des 1,8-Dihydroxyanthrachinons (5a) reagiert mit Acrylsäureester zu den ungewöhnlichen Anthron-Derivaten 12b und 12c.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Einwirkung von Perjodat auf Dextran, Xylan, Inulin und Saccharose führt zu Oxydationsprodukten dieser Zucker, die mit Phenylhydrazin unter anderem Abkömmlinge der Rubazonsäure ergeben.  -  Die gleichen Verbindungen entstehen bei Einwirkung von asymmetrisch disubstituierten Arylhydrazinen auf D-Fructoson-1-phenylhydrazon oder auf Glycerose-phenylosazon und durch Umsetzung von Glycerinaldehyd-methylphenylhydrazon mit Phenylhydrazin. Es wird über Synthese und Eigenschaften dieser Verbindungen berichtet.
    Additional Material: 3 Ill.
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 595 (1991), S. 211-215 
    ISSN: 0044-2313
    Keywords: Tetraphenylphosphonium heptathiacyclo thioarsenate(III) ; synthesis ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Tetraphenylphosphonium Heptathiacyclo Thioarsenate(III), PPh4[SAsS7]From PPh4[As2SCl5] und K2S5 the title compound was obtained in acetonitrile among other products. According to an X-ray crystal structure analysis, it crystallizes in the orthorhombic space group Pna21 with a = 1 826.1(3), b = 1 312.0(2), c = 1 215.9(2) pm, Z = 4. The structure consists of PPh4+ and [SAsS7]- ions, AsS7 rings in the crown conformation as in S8 being present.
    Notes: Aus PPh4[As2SCl5] und K2S5 wurde in Acetonitril unter anderem die Titelverbindung erhalten. Nach der Röntgenstrukturanalyse mit 1474 beobachteten Reflexen (R = 7,1%, wR = 2,7%) kristallisiert sie rhombisch in der Raumgruppe Pna21; a = 1 826,1(3), b = 1 312,0(2), c = 1 215,9(2) pm, Z = 4. Die Struktur besteht aus PPh4+-und [SasS7]-Ionen, wobei AsS7-Ringe in der Kronenform wie beim S8 vorliegen.
    Additional Material: 2 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 609 (1992), S. 95-98 
    ISSN: 0044-2313
    Keywords: Tungsten bronze, Cs0.29WO3 ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A Novel Synthetic Access to the Tungsten Bronze Cs0.29WO3 and its Crystal StructureThe hexagonal tungsten bronze Cs0.29WO3 was obtained in form of black, prismatic crystal by the reduction of WO3 with molten cesium iodide at 700°C. Its crystal structure was determined by X-ray diffraction (399 unique observed reflexions, R = 0.058). Crystal data: a = 741.2(3), c = 760.0(5) pm, space group P6322, Z = 6. It corresponds to the known structure of hexagonal tungsten bronzes, having tungsten atoms displaced from the octahedra centres by 11.9 pm and with three different W—O bond lengths (198, 191, 187 pm). The WO6 octahedra are slightly titled mutually.
    Notes: Bei der Reaktion von WO3 in einer Caesiumiodid-Schmelze bei 700°C entsteht die hexagonale Wolframbronze Cs0.29WO3 in Form schwarzer, hexagonal-prismatischer Kristalle. Ihre Struktur wurde durch Röntgenbeugung bestimmt (399 beobachtete unabhängige Reflexe, R = 5,8%). Kristalldaten: a = 741,2(3), c = 760,0(5) pm, Raumgruppe P6322, Z = 6. Es handelt sich um die bekannte Struktur der hexagonalen Wolframbronzen mit Wolframatomen, die aus den Oktaedermitten um 11,9 pm herausgerückt sind und mit drei verschiedenen W—O-Bindungslängen (198, 191, 187 pm). Die WO6-Oktaeder sind leicht gegeneinander verkippt.
    Additional Material: 1 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 612 (1992), S. 143-148 
    ISSN: 0044-2313
    Keywords: Caesium tetraoxoplumbate ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Correction of the Crystal Structure of “Cs4PbO3” and the Structural Relationship between the Modifications of Cs4PbO4The compound that has been described as Cs4PbO3 really is Cs4PbO4. It does not crystallize in the space group P21, as assumed, but in P21/c. The observed fictitiuous violation of the extinction law for the c glide plane is due to twinning. The structure was refined using the original data as well as new data from an untwinned crystal. The denomination β-Cs4PbO4 is used to distinguish this structure from another known modification (α-Cs4PbO4). Both structures, α-Cs4PbO4 and β-Cs4PbO4, can be derived from the sphere packing of γ-plutonium when certain voids in its packing are occupied with oxygen atoms.
    Notes: Bei der früher als Cs4PbO3 beschriebenen Substanz handelt es sich tatsächlich um Cs4PbO4. Dieses kristallisiert nicht, wie angenommen, in der Raumgruppe P21, sondern in P21/c. Die beobachtete scheinbare Verletzung des Auslöschungsgesetzes für die c-Gleitspiegelebene ist auf Verzwillingung zurückzuführen. Die Struktur wurde sowohl mit den ursprünglichen Daten wie auch mit neuen Daten eines unverzwillingten Kristalls verfeinert. Die Bezeichnung β-Cs4PbO4 dient zur Unterscheidung von einer bereits bekannten Modifikation (α-Cs4PbO4). Beide Strukturen, α-Cs4PbO4 und β-Cs4PbO4, lassen sich von der des γ-Plutoniums ableiten, wenn bei dieser bestimmte Lücken mit Sauerstoffatomen besetzt werden.
    Additional Material: 4 Ill.
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  • 7
    ISSN: 0044-2313
    Keywords: Rhenium tetrachloride chelate complexes ; preparation ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Chelate Complexes of Rhenium Tetrachloride. The Crystal Structures of ReCl4(DME) and ReCl4(DPPE) · TolanBright green crystals of ReCl4(DME) have been prepared by the reaction of rhenium pentachloride with dimethoxyethane (DME) in dichloromethane. ReCl4(DPPE) · tolan was obtained in form of red crystals by the reaction of the alkyne complex [ReCl4(Ph—C≡C—Ph)(POCl3)] with bis(diphenylphosphino)ethane (DPPE) in dichloromethane. The complexes were characterized by X-ray structure determinations.ReCl4(DME): Space group I42d, Z = 8, 829 observed unique reflexions, R = 0.022. Lattice dimensions at 19.5°C: a = b = 960.60(6), c = 2337.2(6) pm. The complex forms monomeric molecules with DME as chelating ligand; the Re—O bond lengths are 213.1 pm. The chlorine atoms, arranged in trans position to the chelating ligand, have slightly shorter Re—Cl bonds than the chlorine atoms in cis position (232,1 pm).ReCl4(DPPE) · tolan: Space group P21/n, Z = 4,4313 observed unique reflexions, R = 0.040. Lattice dimensions at -80°C: a = 1095.7(1), b = 1764.2(2), c = 1898.0(2) pm, β = 99.229(8)°. The compound consists in form of monomeric molecules [ReCl4(DPPE)] and diphenylacetylene molecules, which are incorporated in the lattice. The two phenyl rings of the tolan molecules are twisted towards each other along the C—C axis with a dihedral angle of 21°. The DPPE molecules are bonded to the rhenium atom in a chelating fashion with medium Re—P lengths of 250.4 pm. The chlorine atoms, arranged in trans position to this ligand, with Re—Cl bond lengths of 234.5 pm are slightly longer than the Re—Cl bonds in cis position with 232.3 pm.
    Notes: ReCl4(DME) wird in Form leuchtend grüner Kristalle durch Reaktion von Rheniumpentachlorid mit Dimethoxyethan (DME) in Dichlormethan hergestellt. ReCl4(DPPE) · Tolan erhielten wir als rote Kristalle bei der Reaktion des Alkinkomplexes [ReCl4(Ph—C≡C—Ph)(POCl3)] mit Bis(diphenylphosphino)ethan (DPPE) in Dichlormethan. Die Komplexe wurden durch röntgenographische Strukturanalysen charakterisiert.ReCl4(DME): Raumgruppe I42d, Z = 8, 829 beobachtete unabhängige Reflexe, R = 2,2%. Gitterkonstanten bei 19,5°C: a = b = 960,60(6); c = 2337,2(6) pm. Der Komplex bildet monomere Moleküle mit dem DME-Liganden als Chelat und Re—O-Abständen von 213,1 pm. Die hierzu trans-ständig angeordneten Chloratome haben mit 228,1 pm etwas kürzere Re—Cl-Bindungen als die cis-ständigen Cl-Atome (232,1 pm).ReCl4(DPPE) · Tolan: Raumgruppe P21/n, Z = 4, 4313 beobachtete, unabhängige Reflexe, R = 4,0%. Gitterkonstanten bei -80°C: a = 1095,7(1); b = 1764,2(2); c = 1898,0(2) pm, β = 99,229(8)°. Der Komplex bildet monomere Moleküle [ReCl4(DPPE)] und in das Gitter eingelagerte Diphenylacetylenmoleküle, deren Phenylringe einen Diederwinkel von 21° zueinander bilden. Die DPPE-Moleküle sind chelatartig am Rheniumatom gebunden mit Abständen Re—P von im Mittel 250,4 pm. Die hierzu trans-ständig angeordneten Chloratome sind mit Re—Cl—Abständen von 234,5 pm etwas länger als die cis-ständigen Re—Cl-Bindungen mit 232,3 pm.
    Additional Material: 5 Ill.
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  • 8
    ISSN: 0044-2313
    Keywords: Silver vanadium bronze ; copper vanadium bronze ; synthesis ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A Novel Means of Synthesis for Vanadium Bronzes. Crystal Structure of β—Ag0.33V2O5. Refinement of the Crystal Structure of ∊—Cu0.76V2O5Ag0.33V2O5 and Cu0.76V2O5 were obtained by heating equimolar mixtures of AgI + V2O5 (700°C) and CuI + V2O5 (525°C), respectively, in sealed quartz glass ampoules. In each case, one of the well-formed crystals served for an X-ray structure analysis. Ag0.33V2O5 has the structure known of the β phase of the vanadium bronzes, i. e. layers of edge-sharing, distorted VO6 octahedra are liked by certain common octahedron vertices, the Ag atoms randomly occupy two positions with occupation probabilities of 0.5. Cu0.76V2O5 has the previously determined structure of the ∊ phase, however, its space group is not Cm but C2/m.
    Notes: Ag0,33V2O2 und Cu0,76V2O5 wurden durch zweiwöchiges Erhitzen von äquimolaren Gemischen AgI + V2O5 (700°C) bzw. CuI + V2O (525°C) in einer Quarzglasampulle erhalten. Mit je einem der gut ausgebildeten Kristalle wurden eine Röntgenstrukturanalyse durchgeführt. Ag0,33V2O5 hat die für die β-Phase der Vanadiumbronzen bekannte Struktur, d. h. Schichten aus verzerrten, kantenverknüpften VO6-Oktaedern sind über bestimmte Oktaederecken verknüpft, die Ag-Atome nehmen statistisch zwei Atomlagen der Koordinationszahl 7 mit halber Besetzungswahrscheinlichkeit ein. Cu0,76V2O5 hat die früher bereits bestimmte Struktur der ∊-Phase, deren Raumgruppe jedoch nicht Cm sondern C2/m ist.
    Additional Material: 4 Ill.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1607-1612 
    ISSN: 0044-2313
    Keywords: Indium polysulfido complexes ; preparation ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Crystal Structures of (PPh4)2[In(S4)(S6)Cl] and (PPh4)2[In(S4)Cl3]InCl and PPh4Cl yield (PPh4)2[In2Cl6] in acetonitrile. This reacts with Na2S4 in presence of PPh4Cl, forming (PPh4)2[In(S4)(S6)Cl]. Its crystal structure was determined by X-ray diffraction (R = 0.075, 2 282 observed reflexions). It is isotypic with (PPh4)2[In(S4)(S6)Br] and contains anions with trigonal-bipyramidal coordination of In, Cl occupying an axial position, and the S4 and S6 groups being bonded in a chelate manner. The reaction of (PPh4)2[In2Cl6] and sulfur in acetonitrile yielded (PPh4)2[InCl5] and (PPh4)2[In(S4)Cl3]. The crystal structure analysis of the latter (R = 0.072, 4 080 reflexions) revealed an anion with distorted trigonal-bipyramidal coordination of In, the S4 group occupying one axial and one equatorial position; the S4 group shows positional disorder.
    Notes: Aus InCl und PPh4Cl entsteht in Acetonitril (PPh4)2[In2Cl6]. Aus diesem wurde mit Na2S4 im Beisein von PPh4Cl (PPh4)2[In(S4)(S6)Cl] erhalten. Seine Kristallstruktur wurde mittels Röntgenbeugung bestimmt (R = 7,5%, 2 282 beobachtete Reflexe). Es kristallisiert isotyp zum (PPh4)2[In(S4)(S6)Br] und enthält Anionen mit trigonal-bipyramidaler Koordination des In; das Cl-Atom nimmt eine axiale Position ein und die S4- und S6-Gruppe ist jeweils chelatartig gebunden. Aus (PPh4)2[In2Cl6], PPh4Cl und Schwefel entstanden in Acetonitril (PPh4)2[InCl5] und (PPh4)2[In(S4)Cl3]. Nach der Kristallstruktur des letzteren (R = 7,2%, 4 080 Reflexe) ist im [In(S4)Cl3]2--Ion das In-Atom verzerrt trigonal-bipyramidal koordiniert, wobei die S4-Gruppe an eine axiale und eine equatoriale Position gebunden ist; die S4-Gruppe ist fehlgeordnet.
    Additional Material: 2 Ill.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1201-1202 
    ISSN: 0044-2313
    Keywords: Cobalt(II) complex ; 1,2-dimethyl-5-nitro-imidazole ligand ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Crystal Structure of Bis(1,2-dimetyl-5-nitro-imidazole)dichlorocobalt(II)Bis(1,2-dimethyl-5-nitro-imidazol)dichlorocobalt(II) was obtained by reaction of CoCl2 · 6 H2O with 1,2-dimethyl-5-nitro-imidazole in methanol. The compound forms blue crystals which were characterized by IR and UV-vis spectroscopy and by an X-ray crystal structure determination. Co(C5H7N3O2)2Cl2: tetragonal, space group I42d, Z = 8, a = 1142.1(1) pm, c = 2577.3(2) pm. R = 0.036 for 670 independent reflexions. The Co atom is tetrahedrally surrounded by two chlorine and two N atoms at distances of 222.8(2) and 203.5(4) pm.
    Additional Material: 1 Ill.
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