Synthesis of trifluoromethylated 2-benzoyl- and 3-aminoimidazoles from ring rearrangement of 1,2,4-oxadiazole derivative

Fluoroalkylated 2-ylamino-imidazoles have been synthesized by reaction of 3-amino-5-phenyl-1,2,4-oxadiazole with fluorinated b-dicarbonyl compounds and subsequent base-induced BoultoneKatritzky Rearrangement (BKR) of the isolated b-enaminocarbonyl intermediate. Alternatively, one-pot reactions performed in the presence of Montmorillonite K10 favoured the condensation at the 3-amino moiety of the oxadiazole and, in some cases, allowed the direct synthesis of 2-benzoylamino-imidazoles. Hydrolysis of 2-benzoylamino-imidazoles easily yielded fluorinated 2-amino-imidazoles targets.