Question

Which correct sequence of reactions are applied to achieve the following transformation? \[ \text{Benzoyl Chloride} \xrightarrow{H_2, \text{Pd-BaSO}_4} \xrightarrow{\text{dil. NaOH}} \text{Cinnamaldehyde} \] Choose the correct sequence of reactions from the options given below:

• A. Bouveault-Blanc's reduction followed by Kolbe-Schmidt's reaction
• B. Rosenmund's reduction followed by Claisen-Schmidt's reaction
• C. Bouveault-Blanc's reduction followed by Claisen-Schmidt's reaction
• D. Rosenmund's reduction followed by Perkin's reaction

Hint:

The Rosenmund reduction selectively reduces acyl chlorides to aldehydes, and the Claisen-Schmidt reaction forms cinnamaldehyde.

Answer 1

The Correct Option is B

Step 1: Rosenmund's Reduction.
Rosenmund's reduction involves the catalytic hydrogenation of benzoyl chloride using \(H_2\) over a \(Pd-BaSO_4\) catalyst. This process selectively converts the acyl chloride to an aldehyde, specifically producing benzaldehyde.

Step 2: Claisen-Schmidt's Reaction.
The Claisen-Schmidt condensation occurs when benzaldehyde reacts with acetaldehyde in the presence of a base, such as dilute NaOH. This reaction yields cinnamaldehyde.

Step 3: Conclusion.
Therefore, the correct reaction sequence consists of Rosenmund's reduction followed by the Claisen-Schmidt reaction.

Final Answer: \[\boxed{\text{(2) Rosenmund's reduction followed by Claisen-Schmidt's reaction}}\]