Reactivity of highly unsaturated molecules – investigation of the photo-oxidation of Bitumen & chemistry of propargyl carbocations

Abstract

The contents of this thesis have been divided into two separate parts, with permission from Saint Mary’s University. Each part is to be treated as its own self-enclosed thesis, with no relation to each other, even though there may be overlaps in the underlying chemistry. <br>

Investigation of the Photo-Oxidation of Bitumen -

Highly unsaturated organic molecules, commonly referred to as porphyrins, within bitumen are oxidized when exposed to sunlight. These photo-oxidized porphyrins influence the chemical and physical properties of the bitumen. The generation of these oxidized porphyrins have been monitored using infrared spectroscopy (IR), nuclear magnetic resonance (NMR), gas chomatography/mass spectrometry (GCMS), and saturate, aromatic, resin and asphaltene (SARA) analyses. <br> Chemistry of Propargyl Carbocations -

Highly unsaturated organic molecules are very reactive and readily undergo addition reactions. The reactivity of unsaturated molecules will be further modified by the inclusion of a carbocationic center. For instance, the reactivity of an alkyne is believed to increase with the presence of an adjacent carbocation; a structure referred to as a propargyl carbocation. The carbocation will withdraw electron density, causing the alkyne carbon to form a dipole moment and become highly reactive. We have been able to isolate several stable propargyl carbocations and made preliminary investigations into their chemistry.