The ruthenium catalysed oxidation of 1-phenylethanol derivatives with the release of hydrogen gas has been studied. A hydrogen acceptor was introduced in an effort to elucidate the rate-determining step of the reaction. The transfer of hydrogen from complex alcohols to simple aldehydes and ketones was pursued as a process for obtaining simple alcohols for fuel cell applications. The Shvo catalyst was identified as being the most efficient catalyst for the oxidation of difficult substrates. A family of iron analogues of the Shvo catalyst were synthesised and studied as precatalysts for the oxidation of alcohols. Catalyst activation was achieved by the removal of a CO ligand using trimethylamine-N-oxide and the oxidation of 1-phenylethanol derivatives with acetone was studied. Simple aldehydes were evaluated as hydrogen acceptors and a novel formylation reaction was discovered. Asymmetric iron analogues of the Shvo catalyst were synthesised and applied to the asymmetric transfer hydrogenation of acetophenone using 5:2 formic acid/triethylamine. The synthesis of further analogues with a tethering group was investigated to improve catalyst stability and enantioselectivity. Novel chiral diamine and amino-alcohol ligands containing 1,2,3-triazole functionalities were developed as ligands for the asymmetric transfer hydrogenation of ketones. Tridentate diaminotriazoles provided the best activity and selectivity in the reduction reactions with Ru3(CO)12.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:560384 |
| Date | January 2012 |
| Creators | Johnson, Tarn C. |
| Publisher | University of Warwick |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://wrap.warwick.ac.uk/50062/ |
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