What are the characteristic of acid anhydride reaction compared to carboxylic acid reaction? Thank you

1 Answer

Carboxylic acid and acid anhydrides react with amines to form amides through nucleophilic substitution reactions. Carboxylic acid must use DCC in the presence of an amine to avoid the formation of a carboxylate ion.

Explanation:

https://www.khanacademy.org/test-prep/mcat/chemical-processes/carboxylic-acids/a/carboxylic-acid-reactions-overview

https://chem.libretexts.org/Core/Organic_Chemistry/Anhydrides

All the acid anhydride needs are two amines to form an amide, but carboxylic acid needs Dicyclohexylcarbodiimide to reduce the formation of carboxylate ions and raise neutralize the pH of the reaction. Hope this helps.