FLUOROCARBON DERIVATIVES OF NITROGEN. PART 11. SYNTHESIS OF SOME 2-(TRIFLUOROMETHYL)IMIDAZOPYRIDINES FROM TRIFLUOROACETONITRILE

Article abstract of DOI:10.1016/S0022-1139(00)80977-X

3-(t-Butoxycarbonyl)-2-(trifluoromethyl)imidazo<1,2-a>pyridine, prepared from trifluoroacetonitrile and pyridinium t-butoxycarbonylmethylide, reacts smoothly with trifluoroacetic acid to provide 2-(trifluoromethyl)imidazo<1,2-a>pyridine-3-carboxylic acid, which gives 2-(trifluoromethyl)imidazo<1,2-a>pyridine when heated. 3-Cyano-2-(trifluoromethyl)imidazo<1,2-a>pyridine can be obtained via treatment of trifluoroacetonitrile with pyridinium cyanomethylide, which is sufficiently reactive to effect nucleophilic displacement of fluorine from pentafluoropyridine under mild conditions < -> pyridinium cyano(tetrafluoro-4-pyridyl)methylide>.