Novel behaviour and reactivity in 1,1′-bis(diphenylphosphino)ferrocene and 1,1′-bis(diphenylphosphino)cobaltocene cluster derivatives
| Autor: | Douglas S. Shephard, David Reed, Simon Parsons, Brian F. G. Johnson, Andrew Harrison, Lesley J. Yellowlees, Sebastian P Smidt |
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| Rok vydání: | 1998 |
| Předmět: |
Ligand
Stereochemistry Organic Chemistry Biochemistry Magnetic susceptibility law.invention Inorganic Chemistry chemistry.chemical_compound Crystallography Octahedron Ferrocene chemistry law Cobaltocene Materials Chemistry 1 1'-Bis(diphenylphosphino)ferrocene Reactivity (chemistry) Physical and Theoretical Chemistry Electron paramagnetic resonance |
| Zdroj: | Journal of Organometallic Chemistry. 563:113-136 |
| ISSN: | 0022-328X |
| DOI: | 10.1016/s0022-328x(98)00565-8 |
| Popis: | The clusters [Ru 6 C(CO) 16 {Fe(C 5 H 4 P(Ph) 2 ) 2 }] 2 and [Ru 6 C(CO) 15 { μ -Fe(C 5 H 4 P(Ph) 2 ) 2 }] 3 have been synthesised from the reaction of the parent cluster [Ru 6 C(CO) 17 ] 1 with 1,1′-bis(diphenylphosphino)ferrocene (dppf) in THF. The related compound [Ru 5 C(CO) 13 { μ -Fe(C 5 H 4 P(Ph) 2 ) 2 }] 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 31 P-NMR spectra of 3 and 4 in CD 2 Cl 2 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 [Ru 6 C(CO) 15 { μ -dppm}] 5 has demonstrated a significant degree of communication between the redox-active sites in 3 and 4 . The cluster [Ru 5 C(CO) 13 { μ -Co(C 5 H 4 P(Ph) 2 ) 2 }] 7 has also been synthesised from the direct reaction of the parent cluster [Ru 5 C(CO) 15 ] 6 with 1,1′-bis(diphenylphosphino)cobaltocene (dppc). Synthesis of the dppc analogue of 3 was attempted but was thwarted by unfavourable 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 suceptibility of 7 has also been measured, showing an extraordinarily large magnetic moment at ambient temperature. |
| Databáze: | OpenAIRE |
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