\(\,\begin{array}{*{20}{c}}
O \\
{||} \\
{C{H_3} - C - C{H_3}}
\end{array}\xrightarrow[{(ii)\,{H^ + }/{H_2}O}]{{(i)\,C{H_3}MgBr}}\,\begin{array}{*{20}{c}}
{\,\,\,\,OH} \\
| \\
{C{H_3} - C - C{H_3}} \\
| \\
{\,\,\,\,C{H_3}}
\end{array} + \,Mg(OH)Br\)
$\begin{array}{*{20}{c}}
{OH\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{C{H_3}CHC{H_2}C{H_2}N{H_2}}
\end{array}$ $\xrightarrow[{triethyla\min e}]{{ethyl\,formate\,\left( {1\,equiv} \right)}}$
$[Figure]$ $\xrightarrow[{2.\,C{H_3}I\,(l.\,eq.)}]{{1.\,{K_2}C{O_3}}}$