α‐Quaternary Mannich Bases through Copper‐Catalyzed Amination‐Induced 1,2‐Rearrangement of Allylic Alcohols

A novel copper-catalyzed amination-induced 1,2-rearrangement reaction of allylic alcohols has been developed under simple and mild conditions. The commercially available N-fluorobenzenesulfonimide (NFSI) is employed as an amination reagent. In this transformation, not only alkyl, but also aryl substituents can efficiently undergo 1,2-carbon atom migration, thereby providing an efficient and powerful route to prepare a wide range of α-quaternary Mannich bases. The reaction features a broad substrate scope, operational simplicity, and excellent practicality.