Abstract Pyroglutamic acid smoothly reacts with sulfur tetrafluoride at room temperature to afford enantiomerically pure (5S)-5-(trifluoromethyl) pyrrolidin-2-one (92% yield,> 99% ee). Representative one-step transformations of 1 provided both γ-(S)-trifluoromethyl GABA and (2S)-2-(trifluoromethyl) pyrrolidine on a multigram scale.