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  • Publication
    Accès libre
    Template-Directed Synthesis of Hexanuclear Arene Ruthenium Complexes with Trigonal-Prismatic Architecture Based on 2,4,6-Tris(3-pyridyl)triazine Ligands
    Cationic arene ruthenium metalla-prisms of the general formula [Ru6(p-cymene)6(3-tpt)2(OO∩OO)3]6+ (3-tpt = 2,4,6-tris(3-pyridyl)-1,3,5-triazine; OO∩OO = 5,8-dioxido-1,4-naphthoquinonato [1]6+ or 6,11-dioxido-5,12-naphthacenedionato [2]6+) have been obtained from the corresponding dinuclear arene ruthenium complexes [Ru2(p-cymene)2(OO∩OO)Cl2] by reaction with 3-tpt, silver trifluoromethanesulfonate in the presence of an aromatic molecule (1,3,5-tribromobenzene, phenanthrene, pyrene, or triphenylene) that acts as a template. While the large template molecule triphenylene is permanently encapsulated in the metalla-prisms to give the complexes [triphenylene⊂1]6+ and [triphenylene⊂2]6+, 1,3,5-tribromobenzene can be removed in toluene, thus leaving the empty cages [1]6+ and [2]6+, which are isolated as their trifluoromethanesulfonate salts. In the case of the metalla-prism connected by the 5,8-dioxido-1,4-naphthoquinonato bridging ligands, the NMR spectrum reveals two isomers, 1a and 1b, the formation of which can be rationalized by means of multiple NMR experiments (one-dimensional, two-dimensional, ROESY, and DOSY). The empty and filled metalla-prisms, [1]6+, [2]6+, [template⊂1]6+, and [template⊂2]6+, have been characterized by NMR, UV−vis, and IR spectroscopy. The slow exchange processes of a guest molecule moving in and out of the cavity of cages [1]6+ and [2]6+ have been studied in solution with phenanthrene and pyrene. One-dimensional exchange spectroscopic (1D EXSY) measurements show that [phenanthrene⊂1]6+ is in a faster exchange regime than [phenanthrene⊂2]6+ and that phenanthrene is more easily exchanged than pyrene in cages [1]6+ and [2]6+, all observations being consistent with the portal size of the cages.
  • Publication
    Accès libre
    In- and Out-of-Cavity Interactions by Modulating the Size of Ruthenium Metallarectangles
    (2010)
    Barry, Nicolas P.E.
    ;
    Furrer, Julien
    ;
    Cationic (arene)ruthenium-based tetranuclear complexes of the general formula [Ru4(η6-p-cymene)4(μ-N∩N)2(μ-OO∩OO)2]4+ were obtained from the dinuclear (arene)ruthenium complexes [Ru2 (η6-p-cymene)2(μ-OO∩OO)2Cl2] (p-cymene=1-methyl-4-(1-methylethyl)benzene, OO∩OO=5,8-dihydroxy-1,4-naphthoquinonato(2−), 9,10-dihydroxy-1,4-anthraquinonato(2−), or 6,11-dihydroxynaphthacene-5,12-dionato(2−)) by reaction with pyrazine or bipyridine linkers (N∩N=pyrazine, 4,4′-bipyridine, 4,4′-[(1E)-ethene-1,2-diyl]bis[pyridine]) in the presence of silver trifluoromethanesulfonate (CF3SO3Ag) (Scheme). All complexes 4–12 were isolated in good yield as CF3SO3- salts, and characterized by NMR and IR spectroscopy. The host–guest properties of the metallarectangles incorporating 4,4′-bipyridine and (4,4′-[(1E)-ethene-1,2-diyl]bis[pyridine] linkers were studied in solution by means of multiple NMR experiments (1D, ROESY, and DOSY). The largest metallarectangles 10–12 incorporating (4,4′-[(1E)-ethene-1,2-diyl]bis[pyridine] linkers are able to host an anthracene, pyrene, perylene, or coronene molecule in their cavity, while the medium-size metallarectangles 7–9 incorporating 4,4′-bipyridine linkers are only able to encapsulate anthracene. However, out-of-cavity interactions are observed between these 4,4′-bipyridine-containing rectangles and pyrene, perylene, or coronene. In contrast, the small pyrazine-containing metallarectangles 4–6 show no interaction in solution with this series of planar aromatic molecules.
  • Publication
    Accès libre
    Anticancer activity of opened arene ruthenium metalla-assemblies
    (2010)
    Barry, Nicolas P. E.
    ;
    Zava, Olivier
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    Furrer, Julien
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    Dyson, Paul J.
    ;
    Cationic tetranuclear and hexanuclear opened metalla-assemblies incorporating 5,15-bis(4-pyridyl)-10,20-diphenylporphyrin (bpp) or 5,10,15-tris(4-pyridyl)-20-phenylporphyrin (tpp) panels and dinuclear arene ruthenium clips [(p-cymene)2Ru2(OO?OO)2]2+ (OO?OO = oxalato, 2,5-dioxydo-1,4-benzoquinonato (dobq)) have been assembled in the presence of silver triflate. All complexes were characterized by NMR, IR and UV-visible spectroscopy and electrospray ionization mass spectrometry. The cytotoxicities of the tetranuclear and hexanuclear ruthenium complexes have been established on ovarian A2780 and A2780cisR cancer cell lines. The compds. are quite cytotoxic, the most active metalla-assembly being [Ru6(p-cymene)6(dobq)3(tpp)2]6+, with IC50 values of 2.1 ?M and 3.8 ?M against A2780 and A2780cisR cells, resp. [on SciFinder(R)]
  • 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
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    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.
  • Publication
    Accès libre
    Organometallic boxes built from 5,10,15,20-tetra(4-pyridyl)porphyrin panels and hydroxyquinonato-bridged diruthenium clips
    (2008)
    Barry, Nicolas P.E.
    ;
    Govindaswamy, Padavattan
    ;
    Furrer, Julien
    ;
    ;
    Self-assembly of 5,10,15,20-tetra(4-pyridyl)porphyrin (tpp-H2) tetradentate panels with dinuclear arene ruthenium clips [Ru2 (η6-arene)2 (dhbq)Cl2] (arene = C6H5Me, p-PriC6H4Me, C6Me6; dhbq = 2,5-dihydroxy-1,4-benzoquinonato) affords the cationic organometallic boxes [Ru8 (η6-C6H5Me)8 (tpp-H2)2 (dhbq)4]8+ ([1]8+), [Ru8 (η6-p-PriC6H4Me)8 (tpp-H2)2(dhbq)4]8+ ([2]8+) and [Ru8 (η6-C6Me6)8 (tpp-H2)2 (dhbq)4]8+ ([3]8+). These octanuclear cations have been isolated as their triflate salts and characterised by mass spectrometry, NMR and IR spectroscopy. The molecular structure of these systems was deduced by one-dimensional and two-dimensional NMR experiments (ROESY, COSY, HSQC).