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  • Articles: DFG German National Licenses  (6)
  • Organic Chemistry  (3)
  • preparation  (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
    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.
    Type of Medium: Electronic Resource
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  • 3
    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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  • 4
    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.
    Type of Medium: Electronic Resource
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  • 5
    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.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 541-545 
    ISSN: 0044-2313
    Keywords: Dimagnesium trimolybdate(IV) ; molybdenum oxide ; preparation ; crystal structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: η-Mo4O11 and Mg2Mo3O8: a New Way of Synthesis and Refinement of their Crystal StructuresMg2Mo3O8 was obtained by solid state reaction of MgI2 and MoO3 (1:1) at 200°C and subsequent crystallization at 800°C. Under the same conditions, ZnI2 and MoO3 only yielded rather impure Zn2Mo3O8; however, when ZnI2 or CdI2 and MoO3 were taken in a molar ratio of 1:2, well crystallized η-Mo4O11 was obtained. The known crystal structures of Mg2Mo3O8 and η-Mo4O11 were refined with new X-ray diffraction data (R = 0.030 and 0.059, respectively). The kind of twinning of monoclinic η-Mo4O11 is discussed.
    Notes: Durch Festkörperreaktion von MgI2 und MoO3 (1:1) bei 200°C und anschließender Kristallisation bei 800°C entsteht Mg2Mo3O8. Mit ZnI2 entsteht unter den gleichen Bedingungen nur stark verunreinigtes Zn2Mo3O8; beim Einsetzen von ZnI2 oder CdI2 und MoO3 im Molverhältnis von 1:2 wird dagegen gut kristallisiertes η-Mo4O11 erhalten. Die bekannten Kristallstrukturen von Mg3Mo8O8 und η-Mo4O11 wurden mit neuen Meßdaten verfeinert (R = 3,0 bzw. 5,9%). Die Art der Zwillingsbildung des monoklinen η-Mo4O11 wird diskutiert.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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