Dibenzoylperoxide as a Versatile Oxidant for Oxidative Azidations of Phenols Using Quaternary Ammonium Iodides or Bromides.

Abstract Dibenzoylperoxide emerged as a versatile oxidant for quaternary ammonium iodide or bromide‐catalyzed reactions of phenol derivatives with NaN 3 . While the use of iodides allowed for efficient benzylic azidations under these oxidative conditions, the use of bromides allowed for dearomative azidations instead. Both approaches have been successfully applied to different phenol derivatives and a first proof‐of‐concept for an enantioselective variant using chiral quat. ammonium bromides has been obtained as well.