However, under anhydrous conditions at room temperature, it undergoes many addition reactions at the double bond
\( \mathrm{H}_{2} \mathrm{C}=\mathrm{CH}-\mathrm{OCH}_{3} \stackrel{\mathrm{H}^{+}}{\longrightarrow}\) \(\begin{array}{*{20}{c}}
{{{\text{H}}_2}{\text{C}} - \mathop C\limits^ \oplus {\text{H}} - {\text{OC}}{{\text{H}}_3}} \\
{\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\\
{H\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}\) \(\xrightarrow{{B{r^ - }}}\) \(\begin{array}{*{20}{c}}
{Br\,\,\,\,\,} \\
{|\,\,\,\,\,\,\,\,} \\
{{{\text{H}}_3}{\text{C}} - {\text{CH}} - {\text{OC}}{{\text{H}}_3}}
\end{array}\)
$\begin{array}{*{20}{c}}
{OH\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{C{H_3}CHC{H_2}C{H_2}N{H_2}}
\end{array}$ $\xrightarrow[{triethyla\min e}]{{ethyl\,formate\,\left( {1\,equiv} \right)}}$
${C_3}{H_7}OH\,\xrightarrow{{{H_2}S{O_4}}}X\,\xrightarrow{{B{r_2}}}\,Y\xrightarrow{{KOH}}Z$