The preparation of aryl 1‐(2,6‐dimethylphenyl)‐2‐phenyl‐4‐trifluoromethyl‐5‐imidazolyl sulfides and sulfones

A series of aryl 1‐(2,6‐dimethylphenyl)‐2‐phenyl‐4‐trifluoromethyl‐5‐imidazolyl sulfides was prepared by displacement of fluoride from the 5‐position of 1‐(2,6‐dimethylphenyl)‐2‐phenyl‐4‐trifluoromethyl‐5‐fluoroimidazole by substituted thiophenols and by benzyl mercaptan. This displacement reaction occurs much more slowly than the corresponding previously described reactions of 4‐trifluoromethyl‐5‐fluorothiazoles and ‐oxazoles. Several solvent‐base pairs were examined; the reaction was found to work best when dimethyl sulfoxide was used as the solvent and diazabicycloundecene as the base. The sulfides were oxidized to sulfones by treatment with hydrogen peroxide in acetic acid.