Title:Synthesis of 5-(trifluoroacetyl)imidazoles from Bromoenones and
Benzimidamides via Aza-Michael Initiated Ring Closure Reaction
Volume: 21
Issue: 2
Author(s): Alexey R. Romanov*, Evgeniy V. Kondrashov and Sergey V. Zinchenko
Affiliation:
- The Laboratory of Halogen Organic Compound, A. E. Favorsky Institute of Chemistry, Siberian Branch of the Russian
Academy of Sciences, Irkutsk, 664033, Russia
Keywords:
Fluorine-bearing azaheterocycles, imidazoles, CF3-bromoenones, aza-MIRC synthesis, aza-Michael addition, oxidizing agents.
Abstract:
Introduction: A simple method for the preparation of 5-(trifluoroacetyl)imidazoles was
elaborated.
Methods: The reaction of trifluoromethyl(α-bromoalkenyl)ketones with benzimidamides was employed
to afford the target heterocycles in good yields.
Results: The assembly of imidazole core proceeds via aza-Michael adduct formation followed by
intramolecular nucleophilic substitution and spontaneous aromatization as an oxidation sequence.
Conclusion: The yields of target imidazoles can be improved by the use of soft oxidizing agents.