Aromatic aldehydes and ketones are less reactive than correspondingAliphatic compounds. Explain.

Explanation

Aliphatic aldehydes undergo nucleophilic addition more readily than aromatic aldehydes (say-benzaldehyde). This is due to the following two reasons.
(i) Steric reasons : Bulky phenyl group in benzaldehyde hinders than approach of nucleophile to carbonyl carbon.
(ii) Electronic reasons : The carbon atom of the carbonyl group of benzaldehyde is less electrophilic than carbon atom of the carbonyl group present in aliphatic aldehydes. The polarity of the carbonyl group is reduced in benzaldehyde due to resonance as shown below and hence it is reactive than aliphatic aldehydes.