N-heterocyclic carbenes (NHCs) have emerged over the last two decades as an important class of ligands in transition metal complexes, main group chemistry and organocatalysis. NHCs are now common replacements for phosphines in transition metal chemistry. This thesis describes the synthesis of a variety of chiral NHCs mainly derived from a series of bis(oxazolines) prepared from 1,2-amino acids. These imidazolium salts were then deprotonated to from the corresponding carbenes and complexed with various boranes to form novel chiral NHC borane complexes. The ability for these complexes to perform an asymmetric reduction of acetophenone has been extensively investigated, The optimum complex has been used to reduce a selection of prochiral ketones in up to 85 % ee in the presence of a Lewis acid.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:504238 |
| Date | January 2009 |
| Creators | McArthur, David |
| Publisher | University of Bristol |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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