Details

Autor(en) / Beteiligte

• Novikov, Maxim A.
• Ibatov, Yaroslav A.
• Volchkov, Nikolai V.
• Lipkind, Maria B.
• Semenov, Sergei E.
• Nefedov, Oleg M.

Titel

Copper-catalyzed ligand free ring-opening amination of gem-fluorohalocyclopropanes – An efficient route toward 2-fluoroallylamines

Ist Teil von

• Journal of fluorine chemistry, 2017-02, Vol.194, p.58-72

Ort / Verlag

Lausanne: Elsevier B.V

Erscheinungsjahr

2017

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Copper-catalyzed ring-opening amination of gem-chlorofluoro- and gem-bromofluorocyclopropanes easily prepared by carbenic cyclopropanation of olefins affords tertiary 2-fluoroallyl amines in moderate to excellent yields. [Display omitted] •Copper-catalyzed cyclopropyl-allylic rearrangements of gem-fluorohalocyclopropanes.•An effective approach to aryl-, alkyl substituted tertiary 2-fluoroallyl amines.•Preparation of secondary 2-fluoroallyl amines using PMP-protective group.•Synthesis of primary 2-fluoroallyl amines by Gabriel or Delepin amination of halides. Ring-opening amination of gem-chlorofluoro- and gem-bromofluorocyclopropanes with secondary alkyl, aryl amines or hydroxylamines catalyzed by copper(I) or copper(II) compounds with no additional ligands affords tertiary 2-fluoroallylamines or hydroxylamines in moderate to excellent yields. The reaction pathway involves isomerization of gem-fluorohalocyclopropanes to 2-fluoroallyl halides followed by in situ nucleophilic substitution of a halide by an N-nucleophile. The p-methoxyphenyl (PMP) protective group is efficient in the preparation of secondary 2-fluoroallylamines by this method. Primary 2-fluoroallylamines can only be obtained by a stepwise protocol including CuX-catalyzed isomerization of gem-fluorohalocyclopropanes to 2-fluoroallylic halides followed by amination.