67292-47-1Relevant academic research and scientific papers
Novel behaviour and reactivity in 1,1'-bis(diphenylphosphino)ferrocene and 1,1'-bis(diphenylphosphino)cobaltocene cluster derivatives
Shephard, Douglas S.,Johnson, Brian F. G.,Harrison, Andrew,Parsons, Simon,Smidt, Sebastian P.,et al.
, p. 113 - 136 (1998)
The clusters > 2 and > 3 have been synthesised from the reaction of the parent cluster 1 with 1,1'-bis(diphenylphosphino)ferrocene (dppf) in THF.The related compound > 4 is produced from 2 and 3 in more forcing conditions.Both clusters 3 and 4 have been structurally characterised by single crystal X-ray analysis.In 3 the dppf ligand is coordinated in the vicinal form and the cluster core is a highly distorted octahedron.In 4 the vicinal mode is retained but the dppf ligand is coordinated to adjacent basal atoms of a square-base pyramid.The 31P-NMR spectra of 3 and 4 in CD2Cl2 at various temperatures show a high degree of stereochemically non-rigid behaviour.Magnetic susceptibility measurements across a range of temperatures indicate that 3 is paramagnetic at all temperatures.An electrochemical study of 1, 3, 4 and the related > 5 has demonstrated a significant degree of communication between the redox-active sites in 3 and 4.The cluster > 7 has also been synthesised from the direct reaction of the parent cluster 6 with 1,1'-bis(diphenylphosphino)cobaltocene (dppc).Synthesis of the dppc analogue of 3 was attempted but was thwarted by unfavorable redox chemistry.EPR spectra have been obtained for both dppc and 7.The oxidation product of 7 has also been produced (7+) and displays a high degree of stereochemically non-rigid behaviour in a fashion similar to 3 and 4.The magnetic susceptibility of 7 has also been measured, showing an extraordinarily large magnetic moment at ambient temperature. - Keywords: ruthenium clusters; 1,1'-bis(diphenylphosphino)ferrocene; 1,1'-bis(diphenylphosphino)cobaltocene
Synthesis, electrochemistry, and reactivity of half-sandwich ruthenium complexes bearing metallocene-based bisphosphines
Shaw, Anthony P.,Norton, Jack R.,Buccella, Daniela,Sites, Lauren A.,Kleinbach, Shannon S.,Jarem, Daniel A.,Bocage, Katherine M.,Nataro, Chip
, p. 3804 - 3814 (2009/12/04)
The bimetallic complexes CpRu(P-P)X [Cp = n5-C5H 5; X = Cl, H; P-P = dppf (1,1′-bis(diphenylphosphino)ferrocene) , dppr (1,1′-bis(diphenylphosphino)ruthenocene), dppo (1,1′- bis(diphenylphosphino)-osmocene), dippf (1,1′-bi
Ionic phosphine ligands with cobaltocenium backbone: Novel ligands for the highly selective, biphasic, rhodium-catalyzed hydroformylation of 1-octene in ionic liquids
Brasse, Claudia C.,Englert, Ulli,Salzer, Albrecht,Waffenschmidt, Horst,Wasserscheid, Peter
, p. 3818 - 3823 (2008/10/08)
The use of electron-poor phosphine-substituted cobaltocenium salts as ligands for the biphasic hydroformylation in ionic liquids has been investigated. Using improved oxidation methods, 1,1′-bis(diphenylphosphino)cobaltocenium nitrate, 1,1′-bis(diphenylphosphino)cobaltocenium hexafluorophosphate, and 1,1′-bis[1-methyl(1-diphenylphosphino)ethyl]cobaltocenium hexafluorophosphate have been synthesized. 1,1′-Bis(diphenylphosphinocobaltocenium hexafluorophosphate in particular proved to be a very suitable ligand for the biphasic hydroformylation of 1-octene in 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM PF6), enabling high catalyst activity, high selectivity to the n-product, and no detectable catalyst leaching. In contrast to aqueous biphasic systems, the ionic liquid BMIM PF6 provides for the rhodium catalyst a low-coordinating medium with limited but sufficient solubility for 1-octene to allow high reaction rates.
Synthesis, molecular structure, and molybdenum complexes of 1,1′-bis(diphenylphosphino)cobaltocene
DuBois, Daniel L.,Eigenbrot Jr., Charles W.,Miedaner, Alex,Smart, James C.,Haltiwanger, R. Curtis
, p. 1405 - 1411 (2008/10/08)
The synthesis of 1,1′-bis(diphenylphosphino)cobaltocene (1), (C5H4PPh2)2Co, from TlC5H4PPh2 and CoCl2 is described. The ligand 1 coordinates to one Mo(CO)4 fragment as a chelating bidentate ligand to form [Co(C5H4PPh2)2] [Mo(CO)4] (2) and to two Mo(CO)5 fragments as a bridging bidentate ligand to form [Co(C5H4PPh2)2] [Mo(CO)5]2 (3). Molecular structure determinations have been carried out on compounds 1 and 3. Compound 1 crystallizes in the monoclinic space group P21/c with cell dimensions a = 8.5966 (16) ?, b = 18.765 (4) ?, c = 8.8137 (15) ?, β = 99.702 (14)°, Z = 2, and ρ = 1.32 g cm-3. The structure was solved from 1735 observed reflections (F > 6σ(F)) and refined to final residuals of R = 0.033 and Rw = 0.041. Compound 3 crystallizes in the monoclinic space group C2/c with a = 16.651 (5) ?, b = 12.669 (6) ?, c = 26.322 (9) ?, β = 99.42 (2)°, Z = 4, and ρ = 1.47 g cm-3. The structure was solved from 1474 reflections (F > 6σ(F)) and refined to final residuals of R = 0.048 and Rw = 0.060. The puckering of the substituted cyclopentadienyl ring of 1 is interpreted with the aid of molecular orbital calculations. Cyclic voltammetry of 1 and Fe(C5H4PPh2)2 (4) and their complexes indicate that substitution of the cyclopentadienyl ring and coordination of 1 and 4 to molybdenum carbonyl fragments affects both the redox potential and electrochemical reversibility of electron-transfer processes occurring at cobalt and iron.
