• Development and Investigation of the Fluorescence of Cyclopropenium Ions

      Guest, Matt; Department of Chemistry
      The work presented herein employs cyclopropenium ions as a central design element towards the goal of developing fluorescent, superbasic and boronium-substituted compounds. A novel guanidine-cyclopropenimine proton sponge with exceptional basicity is reported that was further utilized to develop a stable tetracoordinate boronium-substituted proton sponge. A large focus of this thesis was also placed on the development of the recently discovered fluorescence of cyclopropenium ions leading to a new class of small molecule organic fluorophores. Among this new platform of fluorescent compounds, a specific fluorophore featured an impressive photophysical profile that bodes well for future applications in fluorescent imaging techniques. Insight into the structure, electronics, bonding and photophysical properties of these derivatives is offered.
    • The Synthesis of α-Tocopentaenol (αT5), a Fluorescent Analogue of α-Tocopherol

      Hildering, Andrew; Department of Chemistry
      This thesis is focused on the investigation of synthesizing a fluorescent analogue of vitamin E, α-tocopentaenol (αT5). α-Tocopentaenol contains five conjugated double bonds across the phytyl tail, resulting in its fluorescence characteristics. Different methodologies of preparation were attempted to synthesize an all trans-configuration in the five-conjugated double bonds. Unfortunately, across the C3’ bond on the tail, geometric isomers were obtained. However, TBSO-αT5 was produced in what appeared to be ≈ 2:1 E:Z mixture across the C3’ bond (having the four other olefins with trans-configurations). α-Tocopentaenol showed a strong absorbance in ethanol with a maximum λab= 338 nm. This compound is stable as an oil, stored at -78˚C and protected from light for over a month with minimal degradation. Because αT5 resembles the naturally occurring form of the vitamin E, this analogue will enhance our ability to study the biological activity of vitamin E and will create an easy method of monitoring its presence in solution and cells.