Abstract
The dinuclear complex [Co2(CO)6{P(OPh) 3}2] (2) has been synthesised and was fully characterised. The solid state structure revealed a trans diaxial geometry, no bridging carbonyls, and Co-Co and Co-P bond lengths of 2.6722(4) and 2.1224(4) A, respectively. Catalysed hydroformylation of 1-pentene with 2 was attempted at temperatures in the range 120 to 210°C and pressures between 34 and 80 bar. High pressure spectroscopy (HP-IR and HP-NMR) was used to detect hydride intermediates. High pressure infrared (HP-IR) studies revealed the formation of [HCo(CO)3P(OPh)3] (4) at ca. 110°C, but at higher temperatures absorption bands corresponding to [HCo(CO)4] (3) were observed. The hydride intermediate 4 has also been synthesised and characterised. Upon increased ligand concentration, HP-IR studies showed the formation of new carbonyl absorption bands due to a higher substituted cobalt carbonyl complex-[HCo(CO)2{P(OPh)3}2] (5), which is believed to be catalytically less active. Complex 5 has been synthesised independently and was fully characterised. A low temperature crystal structural study of 5 revealed a trigonal bipyramidal structure with a trans H-Co-CO arrangement and two equatorial phosphite ligands, the Co-P bond lengths being 2.1093(8) and 2.1076(8) Å, respectively.
Original language | English |
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Pages (from-to) | 1679-1686 |
Number of pages | 8 |
Journal | Dalton Transactions |
Issue number | 11 |
DOIs | |
Publication status | Published - 7 Jun 2004 |
ASJC Scopus subject areas
- Inorganic Chemistry