Voici les éléments 1 - 2 sur 2
  • Publication
    Accès libre
    Designing the Host-Guest Properties of Tetranuclear Arene Ruthenium Metalla-Rectangles to Accommodate a Pyrene Molecule
    (2010)
    Barry, Nicolas P. E.
    ;
    Furrer, Julien
    ;
    ; ;
    Cationic tetranuclear arene ruthenium complexes of the general formula [Ru4(p-cymene)4(N∩N)2(dhnq)2]4+ comprising rectangular structures are obtained in methanol from the reaction of the dinuclear arene ruthenium precursor [Ru2(p-cymene)2(dhnq)2Cl2] (dhnq = 5,8-dihydroxy-1,4-naphthoquinonato) with pyrazine or bipyridine linkers [N∩N = pyrazine, 1; 4,4-bipyridine, 2; 1,2-bis(4-pyridyl)ethylene, 3] in the presence of AgCF3SO3. All complexes 1-3, isolated in good yield as triflate salts, have been characterised by NMR and IR spectroscopy. The interaction of these rectangular complexes with pyrene as a guest molecule has been studied in solution by various NMR techniques (1D, DOSY, ROESY). In [D3]acetonitrile, the pyrazine-containing metalla-rectangle 1 shows no meaningful interactions with pyrene. On the other hand, the 4,4-bipyridine- and 1,2-bis(4-pyridyl)ethylene-containing metalla-rectangles 2 and 3 clearly interact with pyrene in [D3]acetonitrile. DOSY measurements suggest that, in the case of [Ru4p-cymene)4(4,4-bipyridine)2(dhnq)2]4+ (2), the interactions occur on the outside of the rectangular assembly, while in the case of [Ru4(p-cymene)4{1,2-bis(4-pyridyl)ethylene}2 (dhnq)2]4+ (3), the pyrene molecule is found inside the hydrophobic cavity of the metalla-rectangle, thus giving rise to a host-guest system.
  • Publication
    Accès libre
    Encapsulation of Triphenylene Derivatives in the Hexanuclear Arene Ruthenium Metallo-Prismatic Cage [Ru6 (p-PriC6H4Me)6(tpt)2 (dhbq)3]6+ (tpt = 2,4,6-tri(pyridin-4-yl)-1,3,5-triazine, dhbq = 2,5-dihydroxy-1,4-benzoquinonato)
    (2008)
    Govindaswamy, Padavattan
    ;
    Furrer, Julien
    ;
    ;
    A large cationic triangular metallo-prism, [Ru6(p-PriC6H4Me)6 (tpt)2 (dhbq)3]6+ (1)6+, incorporating p-cymene ruthenium building blocks, bridged by 2,5-dihydroxy-1,4-benzoquinonato (dhbq) ligands, and connected by two 2,4,6-tri(pyridin-4-yl)-1,3,5-triazine (tpt) subunits, allows the permanent encapsulation of the triphenylene derivatives hexahydroxytriphenylene, C18H6 (OH)6 and hexamethoxytriphenylene, C18H6 (OMe)6. These two cationic carceplex systems [C18H6 (OH)6⊂1]6+ and [C18H6 (OMe)6⊂1]6+ have been isolated as their triflate salts. The molecular structure of these systems has been established by one-dimensional 1H ROESY NMR experiments as well as by the single-crystal structure analysis of [C18H6 (OMe)6⊂1][O3SCF3]6.