The comparison of catalysts for producing chiral materials is of vital importance in the improvement of reaction scope and efficacy. Here we describe a new method of analysing the kinetics of the stereodetermining steps in asymmetric reactions by performing ligand/catalyst competition experiments against an internal standard and measuring the enantiomeric excess obtained at a variety of ratios of ligand/catalyst to internal standard. From these enantiomeric excess measurements, we can establish the relative rate of reaction between the ligand/catalyst systems and the internal standard, allowing us to make indirect comparisons of the rates at which the ligands/catalysts perform the reaction. Here we take this method and apply it to three common synthetic procedures: the Sharpless asymmetric dihydroxylation, the asymmetric Michael addition of malonates to nitroalkenes and palladium catalysed asymmetric allylation reaction.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:560106 |
| Date | January 2011 |
| Creators | Rushworth, Philip John |
| Publisher | University of Warwick |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://wrap.warwick.ac.uk/45827/ |
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