Multivicinal fluorine substitution of the cyclohexane ring
Abstract
Highly polar organic fluorinated motifs are of interest in materials chemistry, for
example, in liquid crystal applications. Cyclohexane is an important and widely used
structural motif within organic chemistry. Work has been carried out to prepare
single stereoisomers of multivicinal fluorinated cyclohexanes, a class of compounds
that has not been previously produced. A synthesis of the all-syn-1,2,3,4-tetrafluorocyclohexane, in 9 steps from cyclohexa-1,3-diene will be presented. The
¹⁹F NMR spectra of the all-syn-1,2,3,4-tetrafluorocyclohexane shows interesting
dynamic conformational effects. This is a small polar organic molecule, which was
crystalline at room temperature. The structure of the compound was confirmed by
single crystal X-ray diffraction studies.
The synthesis of the all-syn-1,2,4,5-tetrafluorocyclohexane from cyclohexa-1,4-diene is also presented. The synthesis of a single diastereoisomer of 1,2,3,4,5,6-hexafluorocyclohexane, derived from benzene in 5 steps, is presented. As with the tetrafluoro compounds, the ¹⁹F NMR spectra of this compound shows dynamic conformational effects. The
structure of the compound was confirmed by single crystal X-ray diffraction
studies. The 1,2,4,5-tetrafluorocyclohexane motif was elaborated to contain a phenyl
group, producing “rod-like” molecules. This motif was synthesised in view of
potential applications for liquid crystalline materials.
Type
Thesis, PhD Doctor of Philosophy
Rights
Embargo Date: Electronic copy restricted until 15th April 2016
Embargo Reason: Thesis restricted in accordance with University regulations
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