Question

What is the meaning of acetylation of acetic acid in preparing aldehydes by oxidising the alkyl group of benzene.

Answer 1

Acetylation is defined as the process in which an acetyl group is introduced in a molecule. This can be done either by using acetic anhydride or by using acetyl chloride.

Acetic acid in the presence of dehydrating agent (P₂O₅) gets converted to acetic anhydride.

Methyl benzene under goes oxidation in the presence CrO₃ and acetic anhydride gives benzaldehyde.