Question

How will you prepare cinnamic acid from benzaldehyde?

Answer 1

Conversion of benzaldehyde into cinnamic acid:

\[\begin{array}{cc}
\phantom{....}\ce{COOH}\phantom{...............}\ce{COOH}\phantom{......}\\
\phantom{....}/\phantom{.....................}/\phantom{.............}\\
\ce{\underset{(Benzaldehyde)}{C6H5CH = O} + H2C ->[Pyridine][-H2O] C6H5CH = C ->[\Delta][-CO2] \underset{(Cinnamic acid)}{C6H5CH = CH} - COOH}\\
\phantom{....}\backslash\phantom{.....................}\backslash\phantom{.............}\\
\phantom{}\ce{\underset{(Malonic acid)}{COOH}}\phantom{.............}\ce{COOH}\phantom{....}
\end{array}\]