Stoeckli-Evans, Helen

2001, Diz, Enrique Lozano, Neels, Antonia, Stoeckli-Evans, Helen, Süss-Fink, Georg

The diphosphine clusters Ru-3(CO)(10)(dcpm) (1) and Ru-3(CO)(10)(F-dppe) (2) as well as the bis(diphosphine) clusters Ru-3(CO)(8)(dcpm)(2) (3) and Ru-3(CO)(8)(F-dppe)(2) (4) have been synthesised from Ru-3(CO)(12) and the bulky diphosphines 1,2-bis[bis(pentafluorophenyl)phosphino]ethane (F-dppe) and bis(dicyclohexylphosphino)methane (dcpm). While the single-crystal X-ray structure analyses of 1, 2 and 3 show the expected mu (2)-eta (2) coordination of the diphosphine ligands, that of 4 reveals an unusual structure with one mu (2)-eta (2)-diphosphine and one mu (1)-eta (2)-diphosphine ligand. The clusters 1-4 catalyse the hydroformylation of ethylene and propylene to give the corresponding aldehydes, 2 showing higher activities than those observed for Ru-3(CO)(12) and Ru-3(CO)(10)(dppc). (C) 2001 Elsevier Science Ltd. All rights reserved.

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.

1998, Süss-Fink, Georg, Plasseraud, Laurent, Ferrand, Vincent, Stanislas, Sandrine, Neels, Antonia, Stoeckli-Evans, Helen, Henry, Marc, Laurenczy, Gábor, Roulet, Raymond

Para-cymene ruthenium dichloride dimer reacts in aqueous solution with sodium molybdate or sodium vanadate to give the amphiphilic clusters [(eta(6)-p-MeC(6)H(4)iPr)(4)Ru4Mo4O16] (1) and [(eta(6)-p-MeC(6)H(4)iPr)(4) Ru4V6O19] (4) respectively. The analogous reaction of hexamethylbenzene ruthenium dichloride dimer with sodium vanadate gives [(eta(6)-C6Me6)(4)Ru4V6O19] (5). The mixed-metal clusters [(eta(6)-p-MkC(6)H(4)iPr) Ru(eta(5)-C5Me5)(3)Rh3Mo4O16] (2) and [(eta(6)-p-MeC(6)H(4)iPr)(2)Ru-2(eta(5)-C5Me5)(2)Rh(2)Mo(4)O16] (3) are accessible from a mixture of para-cymene ruthenium dichloride dimer and pentamethylcyclopentadienyl rhodium dichloride dimer with sodium molybdate in aqueous solution. The crystal structure analyses of 1 and 3 reveal different framework geometries of the metal oxygen skeletons. O-17 NMR spectroscopy and partial charge calculations confirm the presence of three different types of oxygen atoms in 1. (C) 1998 Elsevier Science Ltd. All rights reserved.

2001, Faure, Matthieu, Onidi, Anne, Neels, Antonia, Stoeckli-Evans, Helen, Süss-Fink, Georg

The dinuclear cation [(eta (5)-C5Me5)(2)Ir2(mu (2)-H)(3)](+) (1) reacts in aqueous solution with pyrazole and 4-methylpyrazole to give the bispyrazolato complexes [(eta (5)-C5Me5)(2)Ir-2(mu (2)-H)(mu (2)-eta (1),eta (1)-N2C3H2R)(2)](+) (R = H, 2; R = Me, 3). The reaction of complex 1 with 1,2,4-triazole results in the formation of the bistriazolato complex [(mu (5)-C5Me5)(2)Ir-2(mu (2)-H)(mu (2)-eta (1),eta (1)-N3C2H2)(2)](+) (4). Successive protonation of the triazolato ligands in 4 leads to the complexes [(eta (5)-C5Me5)(2)Ir-2(mu (2)-H)(mu (2)-eta (1),eta (1)-N3C2H2)(mu (2)-eta (1),eta (1)-N3C2H3)](2+) (5) and [(eta (5)-C5Me5)(2)Ir-2(mu (2)-H)(mu (2)-eta (1),eta (1)-H3C2H3)(2)](3+) (6). The reaction of 1 with 1,2,3-triazole gives a 1:1 mixture of the bistriazolato complexes [(eta (5)-C5Me5)(2)Ir-2(mu (2)-H)(mu (2)-eta (1),eta (1)-N3C2H2)(2)](+) with parallel (7a) and antiparallel (7b) coordination of the triazolato ligands. The X-ray structure analysis of 3 reveals a diiridium backbone which is bridged by two pyrazolato ligands, the N-N axis being coordinated in a mu (2)-eta (1),eta (1) fashion. (C) 2001 Elsevier Science B.V. All rights reserved.

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.

1998, Dorta, Reto, Stoeckli-Evans, Helen, Bodensieck, Ulf, Süss-Fink, Georg

Melamine, C3N3(NH2)(3), was found to react with [Ru-3(CO)(12)] to give, with N-H activation, the monometallated derivative [Ru-3(mu(2)-H)(CO)(9){mu(3),eta(2)-NHC3N3(NH2)(2)}] (1) and the two isomeric bimetallated derivatives cis-[{Ru-3(mu-H)(CO)(9)}(2){mu(3),eta(2) : mu(3),eta(2) - NHC3N3(NH2)}] (cis-2) and trans-[{Ru-3(mu-H)(CO)(9)}(2){mu(3),eta(2) : mu(3),eta(2)-NHC3N3(NH2)}] (trans-2). The molecular structures of 1, cis-2 and trans-2 have been determined by single-crystal X-ray crystallography. (C) 1998 Elsevier Science S.A.

2000, Süss-Fink, Georg, Fidalgo, Eva Garcia, Neels, Antonia, Stoeckli-Evans, Helen

The dinuclear hydride complex [(p-Me-C6H4-Pr')(2)Ru2Cl2(mu-Cl)(mu-H)] (1) reacts with the sodium halides NaX in methanol to give the halogen analogues [(p-Me-C6H4-Pr')(2)Ru2X2(mu-X)(mu-H)] (2: X = F, 3: X = Br, 4: X = I). With HX, complex 1 reacts to give the tetrahalo complexes [(p-Me-C6H4-Pr')(2)Ru2X2(mu-X)(2)] (5: X = Cl, 6: X = Br, 7: X = I); in the case of X = I, a large excess of HI leads to the formation of the cationic complex [(p-Me-C6H4-Pr')(2)Ru-2(mu-I)(3)](+) (8). The X-ray structure analysis of 1 shows a dinuclear Ru-2 backbone with two terminal chloro ligands being irans with respect to each other as the two p-cymene ligands, the two bridging ligands lie in a plane perpendicular to the plane defined by the terminal chloro ligands and the ruthenium atoms. (C) 2000 Elsevier Science S.A. All rights reserved.

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.

1997, Ferrand, Vincent, Gambs, Céline, Derrien, Nadine, Bolm, Carsten, Stoeckli-Evans, Helen, Süss-Fink, Georg

The reaction of the electron-deficient cluster (mu(2)-H)Ru-3(CO)(9)[mu(3)-NS(O)MePh] (1) with para-nitrotolane gives, with coupling of two alkyne units and elimination of the para-nitrophenyl fragment, the trinuclear complexes Ru-3(CO)(9)[mu(3)-eta(3)-PhCCCC(H)Ph][mu(2)-NS(O)MePh] (2) and Ru-3(mu(2)-CO)(CO)(7)[mu(3)-eta(3)-PhCCCC(H)Ph][mu(3)-NS(O)MePh] (3). The resulting organic moiety, coordinated as mu(3)-eta(3)-5e-donor, is best considered as a butenynyl (PhC=C-C=C(H)Ph) ligand in 2 and as a butatrienyl (PhC=C=C=C(H)Ph) ligand in 3. From the reaction mixture, the two isomeric vinyl complexes Ru-3(mu(2)-CO)(2)(CO)(6)[mu(2)-eta(2)-PhC=C(H)(C6H4-p-NO2)][mu(3)-NS(O)M ePh] (4a) and Ru-3(mu(2)-CO)(2)(CO)(6)[mu(2)-eta(2)-(C6H4-P-NO2)-C=C(H)Ph]-[mu(3)-NS(O )MePh] (4b) complexes can also be isolated. (C) 1997 Elsevier Science S.A.