Addition of pentafluoroethyllithium to cyclic imines leads to pentafluoroethyl substituted pyrrolidines, piperidines and azepanes while reaction of cyclic lactims gives rise to 2- pentafluoroethyl imines. Oxidative cleavage of 2-furyl-2-pentafluoroethyl pyrrolidine has been found to be an effective method for the preparation of a racemic α-pentafluoroethyl proline.
