The direct amination of unactivated primary C—H bonds is extremely challenging due to their inert nature.Herein,we report an intramolecular primary C—H amination of sulfamate esters using an iron catalyst derived from iron(ll)triflate and bipyridine.An array of oxathiazinanes were synthesized in moderate to good yields,which were further converted into biologically important azetidines by a one-pot procedure.This research demonstrates the potential of applying simple nitrogen ligands in iron-catalyzed C—H functionalization and offers an accessible alternative to state-of-the-art iron-nitrene chemistry.