The reaction of cyclic imines with the Ruppert–Prakash reagent. Facile approach to α-trifluoromethylated nornicotine, anabazine, and homoanabazine

We have demonstrated that the Ruppert–Prakash reagent is able to react with a number of cyclic imines under acidic condition to afford the corresponding α-trifluoromethyl derivatives of nitrogen heterocycles. 5–7-Membered cyclic imines bearing various alkyl, aryl or heterocyclic group were successfully involved in this transformation. Novel trifluoromethylated analogues of nicotine, anabasine, and homoanabasine alkaloids were synthesized.