1 $\begin{array}{*{20}{c}}
{\,\,\,\,\,\,O}\\
{\,\,\,\,\,\,\,||\,\,}\\
{C{H_3} - C - Cl}
\end{array}$
2 $\begin{array}{*{20}{c}}
{\,\,O}\\
{\,\,||}\\
{C{H_3} - C - OH}
\end{array}$
3 $\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,O\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,||\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\\
{BrC{H_2} - C - C{H_2}C{H_3}}
\end{array}$
4 $\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,O\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,||\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\\
{Ph - C - Ph}
\end{array}$