Enhancing the synthetic utility of silicon: an investigation into organosilicon chemistry

Thesis

The aims of this work were two-fold - to enhance the 'latent functionality' of a silicon centre by expanding the range of functionalisation reactions available to such compounds, and to develop novel silicon-tethered transformations in order to increase the utility of this attractive synthetic strategy.

1. Aryle Silane Oxidation

Building upon the earlier work of Tamao and co-workers, we have developed a mild, functional group-tolerant oxidation of arylsilanes, allowing a wide range of phenols to be readily accessed. One key insight uncovered during this work was the observation that this oxidation could be acheived with sub-stoichiometric quantities of a fluoride promoter, thus allowing several TBS-protected substrates to be oxidised without any concomitant loss of the protecting group.

2. Silicon-Tethering Methodology

In order to utilise our recently acquired expertise in the field of alkoxy arylsilane synthesis, we sought to develop a novel silicon-tethered iron-catalysed biaryl coupling. Unfortunately, despite our considerable efforts, this methodology was found to suffer from reproducibility issues, and thus our attentions subsequently turned to silicon-tethered palladium- and platinum-catalysed processes. These investigations proved to be more fruitful, with the palladium-catalysed methodology affording a small range of silicon-tethered products. Finally, a novel platinum-catalysed hydro-silylation / electrocyclisation cascade was also developed, allowing a substituted arene to be accessed from a dienyne precursor.

Authors: Bracegirdle, S

• Publication date: 2011
• DOI: 10.5287/ora-5jvgdmkme
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: Oxford University, UK
• Language: English
• Keywords: Organosilicon; silicon tethering; oxidation
• Subjects: Organic chemistry