A novel route to fluoroarenes from trifluoroethanol
This Thesis describes the preparation of fluoroarenes using a palladium-catalysed coupling/electrocyclisation methodology. Difluoroenolzinc coupling partners, 1-(N,N-diethylcarbamoyloxy)-2,2-difluoro-1-zinc chloride and 2,2-difluoro-1-(2'-methoxy-ethoxymethoxy)-1-zinc chloride were prepared fro...
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ndltd-bl.uk-oai-ethos.bl.uk-6355372015-12-03T04:17:40ZA novel route to fluoroarenes from trifluoroethanolWilson, Peter2014This Thesis describes the preparation of fluoroarenes using a palladium-catalysed coupling/electrocyclisation methodology. Difluoroenolzinc coupling partners, 1-(N,N-diethylcarbamoyloxy)-2,2-difluoro-1-zinc chloride and 2,2-difluoro-1-(2'-methoxy-ethoxymethoxy)-1-zinc chloride were prepared from trifluoroethanol at near ambient temperature and underwent Negishi coupling with a range of aryl-halides. A co-solvent (N,N-dimethylpropylene urea) was necessary to generate 2,2-difluoro-1-(2'-methoxy-ethoxymethoxy)-1-zinc chloride in good yield. The zinc coupling partners were also converted to (iodo)difluoroenols which participated in Suzuki-Miyaura coupling with a range of aryl-boronic acids and potassium aryl-trifluoroborates. Side reactions of the Suzuki-Miyaura couplings were circumvented by using tertiary butanol as the reaction solvent. Low temperature preparation of trifluoroborate coupling partners, potassium 2,2-difluoro-1-(N,N-diethylcarbamoyloxy)ethenyl trifluoroborate and potassium 2,2-difluoro-1-(2'-methoxy-ethoxymethoxy)ethenyl trifluoroborate, from trifluoroethanol was also accomplished. The trifluoroborates underwent Suzuki-Miyaura coupling with a range of aryl-halides. This Suzuki-Miyaura coupling protocol was used to prepare a range of fluorinated electrocyclisation precursors in modest to good yield. Subsequent electrocyclisation afforded fluorobenzene, fluoronaphthalene and fluorophenanthrene species. The electrocyclisations were investigated computationally in an attempt to rationalise the ease/difficulty of cyclisation.540University of Strathclydehttp://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.635537http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24542Electronic Thesis or Dissertation |
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540 Wilson, Peter A novel route to fluoroarenes from trifluoroethanol |
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This Thesis describes the preparation of fluoroarenes using a palladium-catalysed coupling/electrocyclisation methodology. Difluoroenolzinc coupling partners, 1-(N,N-diethylcarbamoyloxy)-2,2-difluoro-1-zinc chloride and 2,2-difluoro-1-(2'-methoxy-ethoxymethoxy)-1-zinc chloride were prepared from trifluoroethanol at near ambient temperature and underwent Negishi coupling with a range of aryl-halides. A co-solvent (N,N-dimethylpropylene urea) was necessary to generate 2,2-difluoro-1-(2'-methoxy-ethoxymethoxy)-1-zinc chloride in good yield. The zinc coupling partners were also converted to (iodo)difluoroenols which participated in Suzuki-Miyaura coupling with a range of aryl-boronic acids and potassium aryl-trifluoroborates. Side reactions of the Suzuki-Miyaura couplings were circumvented by using tertiary butanol as the reaction solvent. Low temperature preparation of trifluoroborate coupling partners, potassium 2,2-difluoro-1-(N,N-diethylcarbamoyloxy)ethenyl trifluoroborate and potassium 2,2-difluoro-1-(2'-methoxy-ethoxymethoxy)ethenyl trifluoroborate, from trifluoroethanol was also accomplished. The trifluoroborates underwent Suzuki-Miyaura coupling with a range of aryl-halides. This Suzuki-Miyaura coupling protocol was used to prepare a range of fluorinated electrocyclisation precursors in modest to good yield. Subsequent electrocyclisation afforded fluorobenzene, fluoronaphthalene and fluorophenanthrene species. The electrocyclisations were investigated computationally in an attempt to rationalise the ease/difficulty of cyclisation. |
author |
Wilson, Peter |
author_facet |
Wilson, Peter |
author_sort |
Wilson, Peter |
title |
A novel route to fluoroarenes from trifluoroethanol |
title_short |
A novel route to fluoroarenes from trifluoroethanol |
title_full |
A novel route to fluoroarenes from trifluoroethanol |
title_fullStr |
A novel route to fluoroarenes from trifluoroethanol |
title_full_unstemmed |
A novel route to fluoroarenes from trifluoroethanol |
title_sort |
novel route to fluoroarenes from trifluoroethanol |
publisher |
University of Strathclyde |
publishDate |
2014 |
url |
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.635537 |
work_keys_str_mv |
AT wilsonpeter anovelroutetofluoroarenesfromtrifluoroethanol AT wilsonpeter novelroutetofluoroarenesfromtrifluoroethanol |
_version_ |
1718144206107574272 |