Difluoro-λ3-bromane-induced oxidative carbon-carbon bond-forming reactions: Ethanol as an electrophilic partner and alkynes as nucleophiles

Masahito Ochiai, Akira Yoshimura, Takeshi Mori, Yoshio Nishi, Masaya Hirobe

Research output: Contribution to journalArticle

26 Citations (Scopus)


Reported here for the first time are the oxidative couplings of alkynes and primary alcohols yielding conjugated enones. Although the BF3-catalyzed reaction of terminal alkynes with p-trifluoromethylphenyl(difluoro)-λ3-bromane results in the fluoro-λ3-bromanation of triple bonds to afford (E)-β-fluorovinyl-λ3-bromanes, reaction of an alkyne with the difluoro-λ3-bromane in the presence of an alcohol and BF3-Et2O affords directly conjugated enones in good yields. The reaction proceeds in a highly stereo- and regioselective manner under metal-free conditions. Interestingly, no formation of enones was detected, when difluoro-λ3-iodane p-CF3C6H4IF2 was used instead of the λ3-bromane. A mechanism involving a λ3-bromane-induced oxidation of an alcohol to an aldehyde, [2 + 2] cyclization with alkynes yielding 2H-oxetes, and finally the electrocyclic ring opening is discussed.

Original languageEnglish
Pages (from-to)3742-3743
Number of pages2
JournalJournal of the American Chemical Society
Issue number12
Publication statusPublished - 26 Mar 2008
Externally publishedYes


ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

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