In the last century, many literature reports discuss the electron-transfer from simple
alkoxides, in particular NaOtBu and KOtBu, to aryl halides. These reports are controversial
with many providing evidence on the contrary. This thesis will initial focus on explaining the
role of these alkoxides in the transformations and reports on mechanistic investigations.
Heating 9-bromoanthracene I with KOtBu yields 6 principal products (II-VII), all of which can
be explained through radical chemistry (Scheme 1). Additionally, methylated compounds (V,
VIII-X) are formed which are shown to result from the addition of methyl radicals (formed
after electron transfer from tert-butoxide and subsequent collapse of the tert-butoxyl
radical) to arenes. These are the first examples of alkylated arenes resulting from the collapse
of alkoxyl radicals in the BHAS reaction and is undisputable evidence of electron transfer from
KOtBu. Characterisation of the BHAS reaction with iodoarene XI was then significantly studied and
was shown to provide important information about mechanism (Scheme 2). The experiments additionally demonstrated that substrate XI could be utilised as a stringent assay for xylyl
radicals. Finally, determination of radical intermediates in organometallic reactions (e.g. Ni, Pd, Cu)
can be challenging. A strict assay that allows for clear identification of aryl radical
intermediates is required. Using substrate XI as an assay, organopalladium conditions that
promote radical pathways were investigated and systems that direct to a radical route were
disclosed (Scheme 3). [See thesis for schemes illustrations]
| Date of Award | 20 Jan 2023 |
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| Original language | English |
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| Awarding Institution | - University Of Strathclyde
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| Sponsors | University of Strathclyde |
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| Supervisor | John Murphy (Supervisor) & David Nelson (Supervisor) |
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