$[Figure]$ $\xrightarrow[{CHC{l_3}}]{{\mathop {\left( {Pyridinium\,chlorochromate} \right)}\limits^{PCC} }}$
$\begin{array}{*{20}{c}}
{{C_2}{H_5}MgBr + {H_2}C - C{H_2}\xrightarrow{{{H_2}O}}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\backslash \,\,\,\,/} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,O}
\end{array}A$