Fluoroazoles. II. Synthesis and ¹H and ¹⁹F Nmr spectra of 2‐, 4‐, and 5‐Fluoro‐1‐methylimidazole

Abstract

Abstract The three possible ring‐monofluorinated N ‐methylimidazoles have been prepared by photochemical irradiation of the corresponding diazonium tetrafluoroborates. 5‐Fluoro‐1‐methyl‐imidazole was also obtained by methylation of 1‐acetyl‐4‐fluoroimidazole. The 1 H and 19 F nmr spectra of these N ‐methylated fluoroazoles are compared, and the predominance of one tautomeric form in 4(5)‐fluoroimidazole is discussed.