Electrochemical fluorination of N-cyclopentylpyrrolidine gave the corresponding F-amine together with a ring-opened compound N-(F-pentyI)-F-pyrrolidine in the ratio of 1 to 1, in 55% yield. N-cyclohexylpyrrolidine, N-cyclopentylpiperidine, and N-cyclohexylpiperidine were also eletrochemically fluorinated in the same manner to give the corresponding F-amines, their isomers with rearranged structures