Question

How is benzoyl chloride converted into benzaldehyde? Name the reaction

Answer 1

Rosenmund reaction.

• The Rosenmund reaction is a hydrogenation process where molecular hydrogen reacts with the acyl chloride in the presence of catalyst – Palladium on Barium sulfate, to form aldehyde.
• Reaction:
  
• The Rosenmund catalyst (palladium on barium sulfate) is prepared by the reduction of palladium(II) chloride solution with reducing agent formaldehyde in the presence of barium sulfate.

Conversion of Benzoyl chloride into benzaldehyde:

When Benzoyl chloride is hydrogenated in the presence of Palladium on Barium sulphate$(\mathrm{Pd}/{\mathrm{BaSO}}_4)$, It undergoes reduction and the product formed are Benzaldehyde and $\mathrm{HCl}.$

Therefore, Benzaldehyde and by product hydrochloric acid is formed from Benzoyl chloride by the Rosenmund reaction.