Aminoethane can be prepared by a reduction reaction. Identify a starting compound that can be used to prepare aminoethane by reduction, give the necessary reagent and write an equation for the reaction.

Amines can be prepared by reduction of Amides or Nitriles. To give Aminoethane (CH₃CH₂NH₂) we need an Amine or Nitrile with the same number of carbon atoms (2 in this case). This would be Acetamide (CH₃C(O)NH₂) or Acetonitrile (CH₃CN). In both cases a strong reducing agent is suitable, Lithium Aluminium Hydride (LiAlH₄) is perfect. Equations for these reactions are:

CH₃C(O)NH₂ + LiAlH₄ -> CH₃CH₂NH₂

and

CH₃CN + LiAlH₄ -> CH₃CH₂NH₂

Note that: 1. Whilst LiAlH₄ has four hydrides (and so we might think that only x0.25 are needed) once the recution is complete the resulting salt coordinates to the product of the reaction. This means each molecule of LiAlH₄ can only reduce one molecule of amide or nitrile. 2. In both cases the amine is not formed directly from the reaction, but only upon aqueous work up.