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  • 1
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of organic chemistry 56 (1991), S. 1236-1242 
    ISSN: 1520-6904
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1573-1111
    Keywords: Crown compound ; potassium thiocyanate ; crown cation complex ; crystal structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Single crystal X-ray analysis of the hydrated KSCN complex of benzodinaphthopyridino-21-crown-7 (1) (1 : 1 : 1) is reported. Crystals of the complex are orthorhombic,Pnma, withα = 16.946(4),b = 22.298(4),c = 10.390(8) Å andD c = 1.184 g cm−1,Z = 4. The host macroring (1) has a mirror symmetry and exists in a so-called ‘dentists chair’ conformation. The cation (K−) is coordinated to all the six ether oxygen atoms and also weakly to the pyridine N atom. The SCN− anion group has a statistical type of disorder with opposite orientations of S and N such that nitrogen and sulphur are coordinated to K+. Packing of the host molecules is in columns to form quasi channels with K+, SCN−, and H2O being located inside the stacks.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 959-967 
    ISSN: 0009-2940
    Keywords: Crown ethers ; Pyridino crown ethers ; Clathrates ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Molecular Inclusion of Naphtho- and Benzonaphtho-Fused Pyridino Crowns - Crystal Structure of a Dioxane ClathrateNew naphtho- and benzonaphtho-fused pyridino crown compounds 5-7 are synthesized. The new crown ethers form numerous stoichiometric crystalline inclusion complexes with typical dipolar-aprotic and apolar compounds including dimethylformamide and ureas, dimethyl sulfoxide, nitro compounds, and nitriles or dioxane, benzene, and toluene. On the other hand, 5-7 do not include alcohols and other protic compounds. As expected, the monobenzopyridino crown 4, synthesized as a reference compound, is unable to form inclusions. During the synthesis of 4 the 42-membered dimer macro ring 10 is also obtained. The structure of the crystalline dioxane inclusion compound of the trinaphthopyridino crown 7 is determined by X-ray structure analysis. It shows a specific crystal packing of the host molecules providing free lattice interspace which is occupied by the guest molecules. Based on the conformation of the host molecule and by comparison with the crystal structure of the benzo-analogous parent compound 2, conclusions for future design of host molecules for the crystal phase are drawn.
    Notes: Neue Naphtho- und Benzonaphtho-kondensierte Pyridinokronen 5-7 werden synthetisiert. Die neuen Kronenether bilden zahlreiche stöchiometrische kristalline Einschlußkomplexe mit typischen dipolar-aprotischen und apolaren Substanzen, darunter Dimethylformamid und Harnstoffe, Dimethylsulfoxid, Nitroverbindungen und Nitrile bzw. Dioxan, Benzol und Toluol. Hingegen werden von 5-7 mit Alkoholen und anderen protischen Substanzen keine Einschlüsse erhalten. Die zu Vergleichszwecken ebenfalls hergestellte Monobenzopyridinokrone 4 (bei der Synthese fiel der 42 gliedrige dimere Makroring 10 mit an) eignet sich erwartungsgemäß nicht zur Einschlußbildung. Der Bau der kristallinen Dioxan-Einschlußverbindung der Trinaphthopyridinokrone 7 wird durch Röntgenstrukturanalyse bestimmt. Es liegt eine spezifische Kristallpackung der Wirtmoleküle mit freien Zwischenplätzen vor, die von den Gastmolekülen besetzt werden. Aus der Konformation des Wirtmoleküls und einer Gegenüberstellung mit der Kristallstruktur der benzoanalogen Stammverbindung 2 werden Schlußfolgerungen für den zukünftigen Entwurf von Wirtmolekülen in der Kristallphase gezogen.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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