Why don’t ketones undergo oxidation easily?

Reason ketones resist oxidation

1. Structure of aldehydes vs ketones
   • In aldehydes, the carbonyl carbon is attached to one alkyl group and one hydrogen.
   • In ketones, the carbonyl carbon is attached to two alkyl groups (no hydrogen atom bonded to the carbonyl carbon).
2. Ease of oxidation
   • Oxidation of aldehydes involves replacing the hydrogen atom on the carbonyl carbon with a hydroxyl group, which is very easy.
   • Since ketones do not have that hydrogen, oxidation requires breaking a C–C bond, which is much harder and needs strong oxidizing agents.
3. Result of oxidation of ketones
   • With strong oxidizing agents, ketones can be oxidized, but instead of giving simple carboxylic acids, they usually break into mixtures of smaller carboxylic acids.
   • This cleavage makes the process less straightforward than aldehyde oxidation.

In short

• Aldehydes oxidize easily → have a hydrogen on the carbonyl carbon.
• Ketones resist oxidation → lack that hydrogen, so oxidation requires bond cleavage and harsh conditions.