# Can carboxylic acids be oxidised further?

I know that compounds like alcohols can be further oxidized to aldehydes (or ketones) and to carboxylic acids. But, is carboxylic acid the best oxidized form of a given compound? What happens when carboxylic acids further reacts with oxidizing agents like $\ce{KMnO4}$?

• The maximum oxidation product would be $\ce{CO2}$. – Philipp Aug 24 '13 at 13:57

## 1 Answer

In carboxylic acid, the carbon atom of the COOH group is already in high oxidation state, namely +3. In order to reach a higher oxidation state (+4), it requires breaking the C—C bond, typically to form molecular CO2. Thus, oxidation of carboxylic acid in strongly oxidizing conditions is known as a decarboxylation reaction.

• I guess theoretically you could oxidize a carboxylic acid ester to a carbonate ester. Not sure if there is any practical way to do that of course. But you could imagine some crazy probably impossible oxygen insertion reaction that turns methyl acetate to dimethyl carbonate. – Curt F. May 23 '19 at 18:18