| Autor: |
Crause, Chantelle, Bennie, Linette, Damoense, Llewellyn, Dwyer, Catherine L., Grove, Cronje, Grimmer, Neil, Rensburg, Werner Janse van, Kirk, Megan M., Mokheseng, Konrad M., Otto, Stefanus, Steynberg, Petrus J. |
| Zdroj: |
Dalton Transactions; 2003, Vol. 2003 Issue: 10 p2036-2042, 7p |
| Abstrakt: |
A range of tertiary phosphine ligands derived from R--limonene was studied by HP-31P NMR, HP-IR, batch autoclave reactions and molecular modelling during the hydroformylation of 1-dodecene using a cobalt catalyst system and a metal ligand ratio of 1 2. The phosphorus atom was incorporated in a limonene bicycle where the third substituent was systematically varied, Lim-R R CH217CH3, CH29CH3, CH24CH3, CH23CH3, CH23C6H5, CH23CN, CH23OCH2C6H5, CH22OCH2CH3. The activity and selectivity was, to a large extent, governed by the equilibria between the modified and unmodified cobalt catalytic species in the reaction. Linearity ranged from 54 to 71 with Lim-CH23CN yielding the most branched product and Lim-CH24CH3the most linear product. The n iso ratio ratio of linear to 2-methyl branched alcohol also followed the same trend with a ratio of 2.6 for Lim-CH23CN and 4.9 for Lim-CH24CH3. The rate decreased as the linearity increased with pseudo kvalues of 0.5 to 1.1. Hydrogenation of the alkene varied within a narrow band from 5–6. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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