Nitriles react with strong reducing agents like lithium aluminum hydride through a typical nucleophilic acyl substitution to form primary amines. The reaction requires two equivalents of the reducing agent, which act as a source of hydride ions. The mechanism begins with a nucleophilic attack by the hydride ion at the nitrile carbon, forming an imine anion. Next, the imine anion is attacked by another equivalent of the hydride ion, generating a dianion. Lastly, protonation with water gives a primary amine as the final product. Unlike lithium aluminum hydride reduction, nitriles react with one equivalent of a milder reducing agent like diisobutylaluminum hydride, followed by hydrolysis to yield an aldehyde.