Nitriles can be converted to 1° amines by reaction with LiAlH4. During this reaction the hydride nucleophile attacks the electrophilic carbon in the nitrile to form an imine anion. Once stabilized by a Lewis acid-base complexation the imine salt can accept a second hydride to form a dianion. The dianion can then be converted to an amine by addition of water.
Going from reactants to products simplified
1) Nucleophilic Attack by the Hydride
2) Second nucleophilic attack by the hydride.
3) Protonation by addition of water to give an amine
Prof. Steven Farmer (Sonoma State University)