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.
Keywords: Fluorine-bearing azaheterocycles, imidazoles, CF3-bromoenones, aza-MIRC synthesis, aza-Michael addition, oxidizing agents.
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