Explanation:
(a) \(R - CO - R\,'\xrightarrow{{HCN}}\) - $\begin{array}{*{20}{c}}
{\begin{array}{*{20}{c}}
{\,\,\,\,OH} \\
|
\end{array}} \\
{R - C - R'} \\
{|\,\,} \\
{\,\,\,\,CN}
\end{array}\xrightarrow{{LiAl{H_4}}}$ $\begin{array}{*{20}{c}}
{\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,OH}\,\, \\
|
\end{array}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{R - C - C{H_2}N{H_2}} \\
\,\,\, {|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{\,\,\,R'\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}$