Reduction of Nitriles to Amines
Reduction of Nitriles to Amines: Reduction with DIBAL
The reduction with DIBAL ( Diisobutyl aluminum hydride) can be controlled. Always, one molecule of DIBAL transfers one hydride ion only. Because of the bulky iso-butyl groups, steric easily accessible electrophilic centers are attacked preferentially. Therefore, using only one equivalent of DIBAL for the reduction causes the reaction to stop after the transfer of one hydride yielding the corresponding aldehyde after hydrolysis.
Reaction with a second equivalent of DIBAL generates an amino alanate from the intermediate imino alanate (1). Subsequent hydrolysis provides the primary amine.