This thesis describes synthetic applications of α-keto carbocations, which represent potentially useful, but poorly studied, reversed polarity equivalents of enolates.
In the first chapter, a Ag(I) – mediated method for the nucleophilic displacement of α-halocarbonyl compounds to construct carbon-carbon bonds is described. The highly electrophilic nature of the putative α-keto carbocation intermediates enables the use of relatively unreactive nucleophiles in both intra- and intermolecular contexts. Such intermediates also present interesting opportunities for stereocontrol: our efforts to carry out diastereoselective additions to chiral α-keto carbocations are described.
Oxazoles are an important class of heterocycles, and several syntheses are addressed in Chapter 2. Our approach to this class of compounds employs a TMSOTf mediated Ritter reaction to construct the carbon-nitrogen bond. Cycloaddition of 2-alkoxyoxazoles with alkynes presents a facile route for furan synthesis.
The final chapter describes our attempts to apply anion-π interaction in organocatalysis. These interactions between anions and electron-deficient arenes have been characterized in some detail and have recently been applied in ion transport. Applications of prolinol-based secondary amines incorporating electron-deficient aromatic groups are described.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:OTU.1807/32798 |
| Date | 31 August 2012 |
| Creators | Lai, Ping Shan |
| Contributors | Taylor, Mark S. |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | en_ca |
| Detected Language | English |
| Type | Thesis |
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