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Süss-Fink, Georg

Nom
Süss-Fink, Georg
Affiliation principale
Fonction
Professeur ordinaire
Email
georg.suess-fink@unine.ch
Identifiants
https://libra.unine.ch/handle/123456789/385

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  • Publication
    Métadonnées seulement
    Synthesis and characterization of tetrahedral Ru3O clusters with intrinsic framework chirality: a chiral probe of the intact cluster catalysis concept. [Erratum to document cited in CA144:088385]
    (2006)
    Vieille-Petit, Ludovic
    ;
    Süss-Fink, Georg 
    ;
    Therrien, Bruno 
    ;
    Ward, Thomas R.
    ;
    Stoeckli-Evans, Helen 
    ;
    Labat, Gaeel
    ;
    Karmazin-Brelot, Lydia
    ;
    Neels, Antonia
    ;
    Buergi, Thomas
    ;
    Finke, Richard G.
    ;
    Hagen, Collin M.
    On page 6112, Figure 9 was missing and Figure 11 appeared twice. The correct Figure 9 is given. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    Synthesis and Characterization of Tetrahedral Ru3O Clusters with Intrinsic Framework Chirality: A Chiral Probe of the Intact Cluster Catalysis Concept
    (2005)
    Vieille-Petit, Ludovic
    ;
    Süss-Fink, Georg 
    ;
    Therrien, Bruno 
    ;
    Ward, Thomas R.
    ;
    Stoeckli-Evans, Helen 
    ;
    Labat, Gaeel
    ;
    Karmazin-Brelot, Lydia
    ;
    Neels, Antonia
    ;
    Buergi, Thomas
    ;
    Finke, Richard G.
    ;
    Hagen, Collin M.
    Triruthenium mixed-ligand tetrahedral oxo-capped clusters with framework chirality were prepd. by redn. of areneruthenium triaqua dications followed by capping with areneruthenium dimer as racemic mixts.; diastereomeric mixts. were prepd. using chiral ligand; the prepd. complexes hydrogenate 2-acetamidoacrylate with no ee. Reaction of ArRuCl(?-Cl)2ClRuAr and Ar1RuCl(?-Cl)2ClRuAr1 with Ag2SO4 in aq. soln. gave mixt. of [ArRu(OH2)3]2+ and [Ar1Ru(OH2)3]2+, which upon NaBH4 redn. afforded mixed-ligand binuclear complex Ar1Ru(?-H)3RuAr (4, Ar = ?6-C6Me6, Ar1 = ?6-cymene). Reaction of 4 with Ar2RuCl(?-Cl)2ClRuAr2 and H2O gave the trinuclear cluster [(ArRu)(Ar1Ru)(Ar2Ru)(?3-O)(?-H)3]+ (rac-5, Ar2 = ?6-C6H6). Diastereomeric complexes [(ArRu)(Ar1Ru)(Ar*Ru)(?3-O)(?-H)3]+ [(S,R)-7, (R,R)-7; Ar* = (R)-1-phenylethanol] were prepd. by reaction of 4 with [Ar*RuCl(?-Cl)2ClRuAr*] (6). Analogous complex [(ArRu)(Ar1Ru)(Ar3Ru)(?3-O)(?-H)3]+ (8) was prepd. as a racemic mixt. from known (S,S)-Ar3RuCl(?-Cl)2ClRuAr3 [Ar3 = Et (R)-N-acetyl-?-aminobenzeneacetate]; the complex 8 was sepd. into diastereomers by chromatog., the racemization being caused by epimerization of the chiral ?-carbon. The enantiopure diastereomeric triruthenium clusters [(ArRu)(Ar1Ru)(Ar4Ru)(?3-O)(?-H)3]+ [(S,S)-17, (R,S)-17; Ar4 = (R)-N-acetyl-?-aminobenzeneethanol isobutyrate] were finally prepd. from (S,S)-Ar4RuCl(?-Cl)2ClRuAr4 and 4. The chiral Ru3O framework was evidenced by x-ray crystallog., by CD in the UV and IR regions, and by chiral shift reagents in the NMR spectra. To bring evidence for or against the hypothesis of catalytic hydrogenation by intact trinuclear arene ruthenium clusters contg. an oxo cap, catalytic hydrogenation of Me 2-acetamidoacrylate catalyzed by complexes 13 was performed; the complexes showed low catalytic activity and no asym. induction. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    Supramolecular cluster catalysis: facts and problems
    (2004)
    Süss-Fink, Georg 
    ;
    Therrien, Bruno 
    ;
    Vieille-Petit, Ludovic
    ;
    Tschan, Mathieu
    ;
    Romakh, Vladimir B.
    ;
    Ward, Thomas R.
    ;
    Dadras, Massoud
    ;
    Laurenczy, Gabor
    By checking the chem. underlying the concept of supramol. cluster catalysis the authors identified two major errors in their publications related to this topic, which are essentially due to contamination problems. (1) The conversion of the closed cluster cation [H3Ru3(C6H6)(C6Me6)2(O)]+ (1) into the open cluster cation [H2Ru3(C6H6)(C6Me6)2(O)(OH)]+ (2), which the authors had ascribed to a reaction with H2O in the presence of ethylbenzene is simply an oxidn. reaction which occurs in the presence of air. (2) The higher catalytic activity obsd. with ethylbenzene, which the authors had erroneously attributed to the open cluster cation 2, was due to the formation of RuO2·nH2O, caused by a hydroperoxide contamination present in ethylbenzene. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    Isolation and single-crystal x-ray structure analysis of the catalyst-substrate host-guest complexes [C6H6?H3Ru3{C6H5(CH2)nOH}(C6Me6)2(O)]+ (n = 2, 3). [Erratum to document cited in CA140:059771]
    (2004)
    Vieille-Petit, Ludovic
    ;
    Therrien, Bruno 
    ;
    Süss-Fink, Georg 
    ;
    Ward, Thomas R.
    Figure 3 appeared twice and Figure 4 was missing; the cor. Figure 4 is given. [on SciFinder(R)]
  • Publication
    Accès libre
    Supramolecular cluster catalysis : facts and problems
    (2004)
    Süss-Fink, Georg 
    ;
    Therrien, Bruno 
    ;
    Vieille-Petit, Ludovic
    ;
    Tschan, Mathieu J.-L.
    ;
    Romakh, Vladimir B.
    ;
    Ward, Thomas R.
    ;
    Dadras, Massoud
    ;
    Laurenczy, Gabor
    By checking the chemistry underlying the concept of "supramolecular cluster catalysis" we identified two major errors in our publications related to this topic, which are essentially due to contamination problems. (1) The conversion of the "closed" cluster cation [H3Ru3(C6H6)(C6Me6)2(O)]+ (1) into the "open" cluster cation [H2Ru3(C6H6)(C6Me6)2 (O)(OH)]+ (2), which we had ascribed to a reaction with water in the presence of ethylbenzene is simply an oxidation reaction which occurs in the presence of air. (2) The higher catalytic activity observed with ethylbenzene, which we had erroneously attributed to the "open" cluster cation [H2Ru3(C6H6)(C6Me6)2(O)(OH)]+ (2), was due to the formation of RuO2• nH2O, caused by a hydroperoxide contamination present in ethylbenzene.
  • Publication
    Accès libre
    Isolation and single-crystal X-ray structure analysis of the catalyst–substrate host–guest complexes [C6H6⊂H3Ru3{C6H5(CH2) nOH}(C6Me6)2(O)]+ (n = 2, 3)
    (2003-11-01)
    Vieille-Petit, Ludovic
    ;
    Therrien, Bruno 
    ;
    Süss-Fink, Georg 
    ;
    Ward, Thomas R.
    The trinuclear arene-ruthenium cluster cations [H3Ru3{C6H5 (CH2)nOH}(C6Me6)2 (O)]+ (3: n=2, 4: n=3) have been synthesised from the dinuclear precursor [H3Ru2 (C6Me6)2]+ and the mononuclear complexes [{C6H5(CH2)nOH}Ru(H2O)3]2+ in aqueous solution, isolated and characterised as the hexafluorophosphate or tetrafluoroborate salts. Both 3 and 4 are derivatives of the parent cluster cation [H3Ru3 (C6H6)(C6Me6)2(O)]+ (1) which was found to catalyse the hydrogenation of benzene to give cyclohexane under biphasic conditions. The mechanism postulated for this catalytic reaction (‘supramolecular cluster catalysis’), involving the hydrophobic pocket spanned by the three arene ligands in 1, was based on the assumption that the substrate molecule benzene is hosted inside the hydrophobic pocket of the cluster molecule to form a catalyst–substrate host–guest complex in which the hydrogenation of the substrate takes place. With the analogous cluster cations 3 and 4, containing a (CH2)nOH side-arm (n=2, 3) as substituent at the benzene ligand, it was possible to isolate the cationic host–guest complexes as the hexafluorophosphate or tetrafluoroborate salts. The single-crystal X-ray structure analyses of [C6H6⊂3][PF6] and [C6H6⊂4][BF4], compared to that of [3][PF6] show that the substrate molecule benzene is indeed held inside the hydrophobic pocket of 3 and 4, the angle between the metal (Ru3) plane and the aromatic plane being 67° and 89°, respectively.
  • Publication
    Métadonnées seulement
    Supramolecular cluster catalysis: Facts and problems
    (: American Chemical Society, 2003)
    Süss-Fink, Georg 
    ;
    Therrien, Bruno 
    ;
    Vieille-Petit, Ludovic
    ;
    Tschan, Mathieu
    ;
    Romakh, Vladimir B.
    ;
    Ward, Thomas R.
    Organometallic catalysis is generally thought to proceed through a catalytic cycle which involves coordination of the substrate to the metal center and decoordination of the product after the transformation. The water-sol. trinuclear cluster cation [H3Ru3(C6H6)(C6Me6)2(O)]+ (1) and derivs. thereof seem to catalyze the hydrogenation of benzene under biphasic conditions without prior coordination of the substrate, the interactions between catalyst and substrate relying on supramol. host-guest contacts thanks to the hydrophobic pocket spanned by the three arene ligands in the catalyst mol. The concept of supramol. cluster catalysis, the isolation and characterization of the catalyst-substrate host-guest complexes postulated, as well as errors and problems with this chem. will be discussed. [on SciFinder(R)]
  • Publication
    Accès libre
    Mechanistic in situ High-Pressure NMR Studies of Benzene Hydrogenation by Supramolecular Cluster Catalysis with [(η6-C6H6)(η6-C6Me6)2Ru3(μ3-O)(μ2-OH)(μ2-H)2][BF4]
    (2002)
    Laurenczy, Gabor
    ;
    Faure, Matthieu
    ;
    Vieille-Petit, Ludovic
    ;
    Süss-Fink, Georg 
    ;
    Ward, Thomas R.
    In situ high-pressure NMR spectroscopy of the hydrogenation of benzene to give cyclohexane, catalysed by the cluster cation [(η6-C6H6)(η6-C6Me6)2Ru3(μ3-O)(μ2-OH)(μ2-H)2]+2, supports a mechanism involving a supramolecular host-guest complex of the substrate molecule in the hydrophobic pocket of the intact cluster molecule.