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1.
Behaviour of water-soluble dinuclear rhodium complexes in the hydroformylation reaction of oct-1-ene
The biphasic hydroformylation reaction of oct-1-ene, has been investigated by using the water-soluble dinuclear complex [Rh2(μ-StBu)2(CO)2(TPPTS)2] as precursor. Addition of ethanol as a cosolvent dramatically improved the yields but the good regioselectivity in linear aldehyde observed for neat oct-1-ene—water systems (97%) decreased to 83% (for 22% ethanol w/w). It is shown that the dinuclear framework cannot be maintained, that the mononuclear complex [RhH(CO)(TPPTS)3] is formed, and that thiol and significant amounts of [Rh2(μ-StBu)2(CO)4] move into the organic phase. This reaction from the dinuclear species requires the simultaneous presence of water and carbon monoxide. Introduction of the water-soluble thiol HS(CH2)3NMe2 in the bridging positions affords the complex [Rh2(μ-S(CH 2)3NHMe2)2(CO)2(TPPTS)2]Cl2 which can be kept in the aqueous hase but has a low level of catalytic activity. 相似文献
2.
The methoxycarbonylation of styrene has been studied using Pd(OAc)2/L/acid catalytic systems with L being chiral ferrocene- and biphosphole-based ligands. Good activities are obtained in mild conditions. Chemoselectivities and regioselectivities (up to 98% in favour of the branched isomer) are excellent but enantioselectivities remain moderate (ee up to 17%). 相似文献
3.
Duc Hanh Nguyen Frdric Hebrard Josep Duran Alfonso Polo Martine Urrutigoíty Philippe Kalck 《应用有机金属化学》2005,19(1):30-34
Three different kinds of representative monoterpenic alcohol are involved in the palladium‐catalysed cyclocarbonylation reaction. Lactone formation is shown to occur when cyclic ( 1 ), tertiary ( 3 ) and primary allylic alcohol ( 7 ) functions are reacted, in the presence of CO with [HPd(SnCl3)L2] as the active catalytic species. Good yields and selectivities can easily be reached for isopulegol ( 1 ), and dihydromyrcenol ( 3 ). However, more modest results are obtained for the functionalization of geraniol into the original lactone ( 9 ). This lactone can be largely favoured by using a basic chelating diphosphine ligand such as 1,4‐bis(diphenylphosphino)butane. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
4.
Dr. Delphine Crozet Dr. Aitor Gual Dr. David McKay Dr. Chiara Dinoi Dr. Cyril Godard Prof. Martine Urrutigoïty Dr. Jean‐Claude Daran Prof. Laurent Maron Prof. Carmen Claver Prof. Philippe Kalck 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(23):7128-7140
The reactivity of [Rh(CO)2{(R,R)‐Ph? BPE}]BF4 ( 2 ) toward amine, CO and/or H2 was examined by high‐pressure NMR and IR spectroscopy. The two cationic pentacoordinated species [Rh(CO)3{(R,R)‐Ph? BPE}]BF4 ( 4 ) and [Rh(CO)2(NHC5H10){(R,R)‐Ph‐BPE}]BF4 ( 8 ) were identified. The transformation of 2 into the neutral complex [RhH(CO)2{(R,R)‐Ph? BPE}] ( 3 ) under hydroaminomethylation conditions (CO/H2, amine) was investigated. The full mechanisms related to the formation of 3 , 4 and 8 starting from 2 are supported by DFT calculations. In particular, the pathway from 2 to 3 revealed the deprotonation by the amine of the dihydride species [Rh(H)2(CO)2{(R,R)‐Ph? BPE}]BF4 ( 6 ), resulting from the oxidative addition of H2 on 2 . 相似文献
5.
Philippe Kalck René Poilblanc Antoine Gaset Alain Rovera R.P. Martin 《Tetrahedron letters》1980,21(5):459-462
We describe a method to anchor dinuclear rhodium(I) complexes by substitution of the chlorine bridge in Rh2(μ-Cl)2L4 with LiSR where R represents a polymeric chain. The catalytic activity of such complexes compares well with that observed in homogeneous phase. 相似文献
6.
Ariadna Fuente‐Hernàndez Philippe Costes Philippe Kalck Ulises Jáuregui‐Haza Odile Dechy‐Cabaret Martine Urrutigoïty 《应用有机金属化学》2011,25(11):815-819
The CO‐bubbling effect in cycloisomerization reactions of enynes derived from monoterpenes has been studied using PtCl2, [Rh2Cl2(CO)4] and AuCl3 as catalytic systems. All the precursors are efficient catalysts for the cycloisomerization of O‐tethered enynes. The reaction proceeds through exo‐dig and endo‐dig pathways, which are consistent with the exclusive coordination of the alkyne triple bond to the metal center. The CO ligand not only increases the reaction rates but also induces significant variations in the two reaction pathways. Notably, this effect is also strongly dependent on the nature of the starting enyne. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
7.
Amandine Fabrello Chiara Dinoi Lionel Perrin Philippe Kalck Laurent Maron Martine Urrutigoity Odile Dechy‐Cabaret 《Magnetic resonance in chemistry : MRC》2010,48(11):848-856
103Rh NMR represents a powerful tool to assess the global electronic and steric contribution of diphosphine ligands on [Rh(COD)(diphosphine)]+ complexes. In the case of DIOP, BINAP and MeDUPHOS, this approach proved to be more informative than classical CO‐stretching frequency measurements. After validation, this method has been extended to a set of seven diphosphines. 103Rh NMR measurements on [Rh(COD)(diphosphine)]PF6 lead to the following order of donor properties: dppe > MeBPE > MeDUPHOS > dppb > DIOP > BINAP > Tol‐BINAP. This trend has been validated by DFT in the case of DIOP, BINAP and MeDUPHOS. In conjunction, 31P NMR chemical shift has been shown to reflect the ring constraints of the Rh‐diphosphine scaffold. This contribution is a step towards a mechanistic investigation of the catalytic hydrogenation of unsaturated substrates by 103Rh NMR and DFT. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
8.
Andre Maisonnat Philippe Kalck Rene Poilblanc 《Journal of organometallic chemistry》1974,73(2):C36-C38
In the course of the study of the reactivity of the dinuclear complexes [RhCl(CO)(C2H2)]2 and [RhSR(CO)2]2 towards nucleophiles, two series of dinuclear pentacoordinated rhodium(I) complexes, [RhCl(CO)(C2H4)(amine)]2 and [RhSR(CO)2PR3]2, have been isolated. 相似文献
9.
Paneque M Sirol S Trujillo M Carmona E Gutiérrez-Puebla E Mongue MA Ruiz C Malbosc F Serra-Le Berre C Kalck P Etienne M Daran JC 《Chemistry (Weinheim an der Bergstrasse, Germany)》2001,7(18):3869-3879
Compounds of rhodium(I) and rhodium(III) that contain ancillary hydrotris(pyrazolyl)borate ligands (Tp') react with monodentate and bidentate tertiary phosphanes in a step-wise manner, with incorporation of P-donor atoms and concomitant replacement of the Tp' pyrazolyl rings. Accordingly, [Rh(kappa3-TpMe2)(C2H4)(PMe3)] (1b), converts initially into [Rh(kappa2-TpMe2)-(PMe3)2] (3), and then into [Rh(kappa1-TpMe2)-(PMe3)3] (2) upon interaction with PMe3 at room temperature, in a process which can be readily reversed under appropriate experimental conditions. Full disengagement of the Tp' ligand is feasible to give Tp' salts of rhodium(I) complex cations, for example, [Rh(CO)(dppp)2]-[TpMe2,4-Cl] (5; dppp = Ph2P(CH2)3PPh2), or [Rh(dppp)2][TpMe2,4-Cl] (6). Bis(hydride) derivatives of rhodium(III) exhibit similar substitution chemistry, for instance, the neutral complex [Rh(Tp)-(H)2(PMe3)] reacts at 20 degrees C with an excess of PMe3 to give [Rh(H)2-(PMe3)4][Tp] (9b). Single-crystal X-ray studies of 9b, conducted at 143 K, demonstrate the absence of bonding interactions between the [Rh(H)2(PMe3)4]+ and Tp ions, the closest Rh...N contact being at 4.627 A. 相似文献
10.
Gautron S Giordano R Le Berre C Jaud J Daran JC Serp P Kalck P 《Inorganic chemistry》2003,42(18):5523-5530
The active iridium species in the methanol carbonylation reaction has been crystallized as the [PPN][IrI(2)(CO)(2)] complex and the X-ray structure solved, showing a cis-geometry and a square planar environment. Hydriodic acid reacts very quickly with this compound to provide [PPN][IrHI(3)(CO)(2)], the X-ray crystal structure of which has been determined. The two CO ligands remain in mutual cis-position in a pseudooctahedral environment. The same cis-arrangement has been observed from the X-ray structure for [PPN][IrI(3)(CH(3))(CO)(2)] resulting from the slower oxidative addition of CH(3)I to [PPN][IrI(2)(CO)(2)]. By iodide abstraction with InI(3), the anionic methyl complex gave rise to the dimeric neutral complex [Ir(2)(mu-I)(2)I(2)(CH(3))(2)(CO)(4)]. An X-ray structure showed that the methyl ligands are in the equatorial positions of the two octahedrons sharing an edge, formed by the two bridging iodide ligands. All these four complexes have been fully characterized by mass spectrometry, (1)H and (13)C NMR, and infrared both in solution and in the solid state. When necessary, the (13)CO- or (13)CH(3)-enriched complexes have been prepared and analyzed. 相似文献