Nitriles are susceptible to hydrogenation over diverse metal catalysts.  The reaction can afford either the primary amine () or the tertiary amine (), depending on conditions. In conventional organic reductions, nitrile is reduced by treatment with lithium aluminium hydride to the amine.  Reduction to the imine followed by hydrolysis to the aldehyde takes place in the Stephen aldehyde synthesis, which uses stannous chloride in acid.