Question

Acid chlorides can be changed to aldehydes by reaction with :

• A. $LiAl{H}_4$
• B. $NaB{H}_4$
• C. Hydrogen and palladised $BaS{O}_4$
• D. Zinc amalgam and conc. $HCl$

Answer 1

Answer: (C)

Hydrogen and palladised $BaS{O}_4$

Acyl chloride/acid chloride undergoes hydrogenation in the presence of a catalyst such as barium sulfate (BaSO4) or Palladium (Pd) to form aldehydes. Aldehyde formation with this process is possible after the partial poisoning of the reaction by the addition of compounds such as sulfur or quinolone. This is an important step for the formation of aldehydes. This is also known as Rosenmund’s Reaction.

Hence, the correct option is $\text{C}$