One-Pot Telescoping -Transfer and Trifluoromethylation for the Synthesis of 2-CFS-Imidazoles with -Oxides as Convenient Precursors.

Readily available 2-unsubstituted imidazole -oxides were examined as starting materials for the preparation of fully substituted 1,4,5-aryl/alkyl 2-trifluoromethylsulfanyl-imidazoles. Whereas activation of the -oxide function followed by attempted nucleophilic addition of the SCF was in vain, the alternative approach involving "sulfur transfer reaction" and subsequent electrophilic trifluoromethylation with Togni reagent provided target products in high yield via a one-pot procedure. The structure of representative enantiomerically pure imidazol-2-yl trifluoromethyl sulfide was confirmed by X-ray analysis.