Journal of inclusion phenomena

, Volume 2, Issue 1–2, pp 185–194 | Cite as

Dissolving metal reduction K metal-crown ether-toluene system for reductive defluorination

  • Tomihiko Ohsawa
  • Takeshi Oishi
Original Papers

Abstract

Toluene radical anion, generated by dissolving potassium metal in toluene by the assistance of dicyclohexano-18-crown-6, has been proved to be especially effective for reductive removal of fluorine atom from unactivated alkyl fluorides that resist common reduction conditions. Stereochemical and mechanistic aspects of the present method is discussed. In connection with the preparation of substrates the effect of dipolar aprotic solvents on the nucleophilic fluorination with potassium fluoride/dicyclohexano-18-crown-6 system was also examined, and sulfolane or N,N-dimethyl formamide was shown to be a solvent of choice.

Keywords

Toluene Fluorine Formamide Radical Anion Reduction Condition 

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Copyright information

© D. Reidel Publishing Company 1984

Authors and Affiliations

  • Tomihiko Ohsawa
    • 1
  • Takeshi Oishi
    • 1
  1. 1.Riken (The Institute of Physical and Chemical Research)Wako, SaitamaJapan

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