Methods of preparation of Carboxylic Acids

Preparation of Carboxylic Acids From primary alcohols and aldehydes

Carboxylic acids are also prepared from aldehydes by the use of mild oxidising agents.

Preparation of Carboxylic Acids From alkylbenzenes:

Aromatic carboxylic acids can be prepared by vigorous oxidation of alkyl benzenes with chromic acid or acidic or alkaline potassium permanganate.

Preparation of Carboxylic Acids From nitriles and amides:

Nitriles are hydrolysed to amides and then to acids in the presence of H⁺ or OH^– as catalyst. Mild reaction conditions are used to stop the reaction at the amide stage.

Preparation of Carboxylic Acids From Grignard reagents:

Grignard reagents react with carbon dioxide (dry ice) to form salts of carboxylic acids which in turn give corresponding carboxylic acids after acidification with mineral acid.

Preparation of Carboxylic Acids From acyl halides and anhydrides:

Acid chlorides when hydrolysed with water give carboxylic acids or more readily hydrolysed with aqueous base to give carboxylate ions which on acidification provide corresponding carboxylic acids.

Preparation of Carboxylic Acids From esters:

Acidic hydrolysis of esters gives directly carboxylic acids while basic hydrolysis gives carboxylates, which on acidification give corresponding carboxylic acids.