Reductive Amination of Aldehydes Using Aminoboranes as Iminium Ion Generators

2-Dialkylamino-4H-1,3,2-benzodioxaborins, salicyl alcohol derived aminoboranes, serve as efficient and mild iminium ion generators in the reductive amination of aldehydes with NaBH4. Using a diisopropylamino derivative, a variety of amines including secondary and primary amines, and ammonia can participate to the reductive amination in aprotic organic solvents without the use of acidic promoters.