available catalyst consisting of iron dichloride in combination with 1,10‐phenanthroline catalyzes the ring‐closing C−H amination of N‐benzoyloxyurea to form imidazolidin‐2‐ones in high yields. The C−H amination reaction is very general and applicable to benzylic, allylic, propargylic, and completely non‐activated aliphatic C(sp3)−H bonds, and it also works for C(sp2)−H bonds. The surprisingly simple method