How are primary amines synthesized through the reduction of nitriles, and what role does lithium aluminium hydride play in this process?

Primary amines are synthesized through the reduction of nitriles using lithium aluminum hydride (LiAlH₄). In this process, nitriles (RC≡N) react with LiAlH₄, a powerful reducing agent. LiAlH₄ donates hydride ions (H⁻), which reduce the nitrile group to form an imine intermediate (RC=NHR). Further reduction with additional LiAlH₄ or acidic hydrolysis converts the imine to the corresponding primary amine (RCH₂NH₂). Lithium aluminum hydride’s role is critical, as it selectively reduces nitriles without affecting other functional groups, providing a versatile and efficient method for the synthesis of primary amines from nitriles.