Stoeckli-Evans, Helen

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Institut de physique

helen.stoeckli-evans@unine.ch

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https://libra.unine.ch/handle/123456789/470

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Accès libre
Tri- and Tetranuclear Mixed-Metal Clusters Containing Alkyne Ligands : Synthesis and Structure of [Ru₃Ir(CO)₁₁(RCCR’)]^-, [Ru₂Ir(CO)₉(RCCR’)]^-, and [HRu₂Ir(CO)₉(RCCR’)]
(1999)
Ferrand, Vincent
;
Süss-Fink, Georg
;
Neels, Antonia
;
Stoeckli-Evans, Helen
The tetrahedral cluster anion [Ru₃Ir(CO)₁₃]^- (1) reacts with internal alkynes RCCR to afford the alkyne derivatives [Ru₃Ir(CO)₁₁(RCCR)]^- (2: R = R’ = Ph; 3: R = R’ = Et; 4: R = Ph; R’ = Me; 5: R = R’ = Me) which have a butterfly arrangement of the Ru₃Ir skeleton in which the alkyne is coordinated in a μ₄-η² fashion. Under CO pressure they undergo fragmentation to give the trinuclear cluster anions [Ru₂Ir(CO)₉ (RCCR)]^- (6: R = R’ = Ph; 7: R = R’ = Et; 8: R’ = Ph; R’ = Me; 9: R = R’ = Me), in which the alkyne ligand is coordinated in a μ₃-η² parallel fashion. Protonation of these trinuclear anions leads to the formation of the corresponding neutral hydrido clusters [HRu₂Ir(CO)₉ (RCCR)] (10: R = R’ = Ph; 11: R = R’ = Et; 12: R = Ph; R’ = Me; 13: R = R’ = Me). The protonation of the butterfly anions 2 and 3, however, gives rise to the formation of the neutral tetrahedral clusters [HRu₃Ir(CO)₁₁(RCCR)] (14: R = R’ = Ph and 15: R = R’ = Et), respectively. The analogous clusters [HRu₃Ir(CO)₁₁(PhCCCH₃)] (16) and [HRu₃Ir(CO)₁₁(CH₃CCCH₃)] (17) are only accessible from the reaction of the neutral cluster [HRu₃Ir(CO)₁₃] with the corresponding alkynes. The complexes 2, 4, 5, 6, 10, 12 and 15 are characterised by X-ray structure analysis.
Accès libre
Triruthenium–iridium clusters containing alkyne ligands : synthesis, structure, and catalytic implications of [(µ-H)IrRu₃(CO)₁₁(µ₃-η²-PhC≡CPh)] and [IrRu₃(CO)₁₀(µ₄-η²-PhC≡CPh)(µ-η²-PhC=CHPh)]
(1998)
Ferrand, Vincent
;
Süss-Fink, Georg
;
Neels, Antonia
;
Stoeckli-Evans, Helen
The mixed-metal cluster [HIrRu3(CO)₁₃] 1 reacts with one equivalent of disubstituted alkynes RC≡CR to give [HIrRu₃(CO)₁₁(µ₃-η2-RC≡CR)] (R = Ph 2; R = Me 3), with a second equivalent of the alkyne the clusters [IrRu₃(CO)₁₀(µ₄-η2-RC≡CR)(µ-η2-RC=CHR)] (R = Ph 4; R = Me 5) are obtained. The single-crystal X-ray structure analyses of 2 and 3 show these clusters to have a tetrahedral Ru3Ir framework containing the alkyne ligand coordinated in a parallel fashion over the Ru₃ face of the metal skeleton. In contrast, the clusters 4 and 5 consist of a butterfly arrangement of the Ru₃Ir framework with the alkyne ligand coordinated to all four metal atoms, giving an overall octahedral Ru₃IrC₂ skeleton, as demonstrated by the single-crystal structure analysis of 4. Cluster 1 is an excellent catalyst for the hydrogenation of diphenylacetylene to give stilbene (catalytic turnover number 990 within 15 min), clusters 2 and 4 are also catalytically active but seem to represent side-channels of the catalytic cycle.
Accès libre
The mixed-metal carbonyl cluster anion [Ru₃Ir(CO)₁₃]^– : synthesis, molecular structure, fluxionality, reactivity
(1997)
Süss-Fink, Georg
;
Haak, Susanne
;
Ferrand, Vincent
;
Stoeckli-Evans, Helen
The new cluster anion [Ru₃Ir(CO)₁₃]^–1 was synthesized in high yield from [Ru₃(CO)₁₂] and [Ir(CO)₄]^–. The single-crystal X-ray structure analysis of the bis(triphenylphosphoranylidene)ammonium salt revealed the presence of two isomers, [Ru₃Ir(CO)₁₁(µ-CO)₂]^–1a and Ru₃Ir(CO)₉(µ-CO)₄]^–1b in the same crystal. Both 1a and 1b present a tetrahedral Ru₃Ir framework, differing only by the number of bridging carbonyl ligands. Variable-temperature ¹³C NMR spectroscopic studies of 1 revealed the fluxionality of the carbonyl ligands and the interconversion of both isomers in solution. Protonation of 1 gave the neutral cluster [HRu₃Ir(CO)₁₃] 2, whereas reaction of 1 with molecular hydrogen yielded the anion [H₂Ru₃Ir(CO)₁₂]^–3. Either hydrogenation of 2 or protonation of 3 gave [H₃Ru₃Ir(CO)₁₂] 4. The tetrahedral structure of the hydrido derivatives was confirmed by a single-crystal X-ray structure analysis of the bis(triphenylphosphoranylidene)ammonium salt of 3.
Métadonnées seulement
Triruthenium clusters containing vinyl ligands: synthesis and structure of Ru-3(mu(2)-CO)(2)(CO)(6)[mu(3)-NS)(O)MePh](mu(2)-eta(1),eta(2)-PhCH2C=CH 2), Ru-3(mu(2)-CO)(CO)(7)[mu(3)-NS(O)MePh](mu(3)-eta(1),eta(2)-(PrC)-C-n=CHP rn), Ru-3(mu(2)-CO)(CO)(7)[mu(3)-NS(O)MePh](mu(3)-eta(1),eta(2)-PhC=CHBun), and (mu(2)-H)Ru-3(CO)(6)(mu(2)-eta(1),eta(2)-PhC=CHPh)(mu(3)-eta(1),eta(2)-P hC CPh)[mu(3)-eta(1),eta(2)-NS(O)Me(C6H4)]
(1997)
Ferrand, Vincent
;
Merzweiler, Kurt
;
Rheinwald, Gerd
;
Stoeckli-Evans, Helen
;
Süss-Fink, Georg
The electron-deficient cluster (mu(2)-H)Ru-3(CO)(9)[mu(3)-NS(O)MePh] (1) reacts with the terminal alkyne PhCH2C=CH to give the vinyl complex Ru-3(mu(2)-CO)(2)(CO)(6)[mu(3)-NS(O)MePh](mu(2)-eta(1),eta(2)-PhCH2C=CH2 ) (2). The analogous reaction with internal alkynes (RC=CR') affords the clusters Ru-3(mu(2)-CO)(CO)(7)[mu(3)-NS(O)MePh](mu(3)-eta(1),eta(2)-RC=CHR') (3: R = R' = Pr "; 4: R = Ph; R' = Bu ") in which the vinyl ligand has opened a Ru-Ru bond upon coordination the Ru-3 framework. In the case of diphenylacetylene, reaction with two equivalents of the alkyne, yields the vinyl-alkyne cluster (mu(2)-H)Ru-3(CO)(6)(mu(2)-eta(1),eta(2)-PhC=CHPh)(mu(3)-eta(1),eta(2)-P hC=CPh)[mu(3)-eta(1),eta(2)-NS(O)Me(C6H4)] (5) with ortho-metallation of the phenyl substituent of the sulfoximido cap. (C) 1997 Elsevier Science S.A.
Métadonnées seulement
The mixed-metal carbonyl cluster anion [Os3Ir(CO)(13)](-): Synthesis, structure, reactivity and catalytic activity in the carbonylation of methanol
(1999)
Süss-Fink, Georg
;
Haak, Susanne
;
Ferrand, Vincent
;
Stoeckli-Evans, Helen
The cluster anion [Os3Ir(CO)(13)](-) (1) was prepared in 50% yield by reaction of Os-3(CO)(12) with [Ir(CO)(4)](-). The single-crystal X-ray structure analysis of the bis(triphenylphosphoranylidene)ammonium salt shows 1 to consist of a tetrahedral metal core with one of the 13 carbonyl ligands being bridging. Protonation of 1 led to the neutral cluster HOs3Ir(CO)(13) (2), whereas the hydrogenation gave the cluster anion [H2Os3Ir(CO)(12)](-) (3). The catalytic activity of 1 for the carbonylation of methanol was studied. Using CH3I as co-catalyst, catalytic turnover numbers up to 1800 were obtained (140 degrees C, 30 bar) within 14 h. (C) 1999 Elsevier Science B.V. All rights reserved.
Métadonnées seulement
Electron-deficient triruthenium and triosmium clusters from the reaction of the cluster anions [HM3(CO)(11)](-) (M = Ru, Os) with tricyclohexylphosphine in methanol
(1999)
Süss-Fink, Georg
;
Godefroy, Isabelle
;
Ferrand, Vincent
;
Neels, Antonia
;
Stoeckli-Evans, Helen
;
Kahlal, Samia
;
Saillard, Jean-Yves
;
Garland, Maria Teresa
The reaction of Na[HRu3(CO)(11)] with an excess of tricyclohexylphosphine in methanol gives the neutral complex H2Ru3(CO)(6)(PCy3)(3) which is the first 44 e(-) triruthenium cluster reported. This highly electron-deficient species reacts with carbon monoxide to give the saturated 48 e(-) cluster Ru-3(CO)(9)(PCy3)(3). The electronic structure of the novel 44 e- cluster was established by EHT and DFT molecular orbital calculations of isoelectronic model compounds. The analogous reaction of [N(PPh3)(2)][HOs3(CO)(11)] with PCy3 in methanol affords the 46 e(-) cluster H2Os3(CO)(7)(PCy3)(3), the first trisubstituted derivative of H2Os3(CO)(10). In all cases methanol acts as source of protons for the formation of the hydride clusters. (C) 1999 Elsevier Science S.A. All rights reserved.
Métadonnées seulement
Tri- and tetranuclear mixed-metal clusters containing alkyne ligands: Synthesis and structure of [Ru3Ir(CO)(11)(RCCR ')](-), [Ru2Ir(CO)(9)(RCCR ')](-), and [HRu2Ir(CO)(9)(RCCR ')]
(1999)
Ferrand, Vincent
;
Süss-Fink, Georg
;
Neels, Antonia
;
Stoeckli-Evans, Helen
The tetrahedral cluster anion [Ru3Ir(CO)(13)](-) (1) reacts with internal alkynes RC=CR' to afford the alkyne derivatives [Ru3Ir(CO)(11) (RCCR')](-) (2: R = R' = Ph; 3: R = R' = Et; 4: R = Ph; R' = Me; 5: R = R' = Me) which have a butterfly arrangement of the Ru,Ir skeleton in which the alkyne is coordinated in mu(4)-eta(2) fashion. Under CO pressure they undergo fragmentation to give the trinuclear cluster anions [Ru2Ir(CO)(9)(RCCR')](-) (6: R = R' = Ph; 7: R = R' = Et; 8: R = Ph; R' = Me; 9: R = R' = Me), in which the alkyne ligand is coordinated in a mu(3)-eta(2) parallel fashion. Protonation of these trinuclear anions leads to the formation of the corresponding neutral hydride clusters [HRu2Ir(Co)(9)(RC=CR')] (10: R = R' = Ph; 11: R = R' = Et; 12: R = Ph; R' = Me; 13: R = R' = Me). The protonation of the butterfly anions 2 and 3, however, gives rise to the formation of the neutral tetrahedral clusters [HRu3Ir(CO)(11)(RCCR')] (14: R = R' = Ph and 15: R = R' = Et), respectively. The analogous clusters [HRu3Ir(CO)(11)(PhCCCH3)] (16) and [HRu3Ir(CO)(11)(CH3CCCH3)] (17) are only accessible from the reaction of the neutral cluster [HRu3Ir(CO)(13)] with the corresponding alkynes. The complexes 2, 4, 5, 6, 10, 12 and 15 are characterised by Xray structure analysis.
Métadonnées seulement
The Mixed-Metal Carbonyl Cluster Anion [Ru3Ir(CO)13]-: Synthesis, Molecular Structure, Fluxionality, Reactivity
(1997)
Süss-Fink, Georg
;
Haak, Susanne
;
Ferrand, Vincent
;
Stoeckli-Evans, Helen
Métadonnées seulement
[(p-C6H4iPrMe)4Ru4Mo4O16]: An Amphiphilic Organoruthenium Oxomolyb-denum Cluster Presenting a Unique Framework Geometry
(1997)
Süss-Fink, Georg
;
Plasseraud, Laurent
;
Ferrand, Vincent
;
Stoeckli-Evans, Helen
Métadonnées seulement
Triruthenium-iridium clusters containing alkyne ligands: synthesis, structure, and catalytic implications of [(mu-H)IrRu3(CO)(11)(mu(3)-eta(2)-PhC CPh)] and [IrRu3(CO)(10)(mu(4)-eta(2)-PhC CPh)(mu-eta(2)-PhC = CHPh)]
(1998)
Ferrand, Vincent
;
Süss-Fink, Georg
;
Neels, Antonia
;
Stoeckli-Evans, Helen
The mixed-metal cluster [HIrRu3(CO)(13)] 1 reacts with one equivalent of disubstituted alkynes RC=CR to give [HIrRu3(CO)(11)(mu(3)-eta(2)-RC=CR)] (R = Ph 2; R = Me 3), with a second equivalent of the alkyne the clusters [IrRu3(CO)(10)(mu(4)-eta(2)-RC=CR)(mu-eta(2)-RC=CHR)] (R = Ph 4; R = Me 5) are obtained. The single-crystal X-ray structure analyses of 2 and 3 show these clusters to have a tetrahedral Ru3Ir framework containing the alkyne ligand coordinated in a parallel fashion over the Ru, face of the metal skeleton. In contrast, the clusters 4 and 5 consist of a butterfly arrangement of the Ru3Ir framework with the alkyne ligand coordinated to all four metal atoms, giving an overall octahedral Ru3IrC2 skeleton, as demonstrated by the single-crystal structure analysis of 4. Cluster I,is an excellent catalyst for the hydrogenation of diphenylacetylene to give stilbene (catalytic turnover number 990 within 15 min), clusters 2 and 1 are also catalytically active but seem to represent side-channels of the catalytic cycle.

Stoeckli-Evans, Helen

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