The Kolbe–Schmitt reaction also termed as Kolbe process is a carboxylation chemical reaction that proceeds by heating sodium phenoxide with carbon dioxide under pressure, then treating the product with sulfuric acid. The final product is an aromatic hydroxy acid which is also known as salicylic acid. It is named after Hermann Kolbe and Rudolf Schmitt. In simple terms, it is a reaction for adding a carboxyl group onto the benzene ring of a phenol.
The Kolbe reaction can be labelled as a carboxylation chemical reaction. The reaction occurs when sodium phenoxide is allowed to absorb carbon dioxide and the resulting product is heated at a temperature of a 125-degree celsius and a pressure of over a hundred atmospheres. An unstable intermediate is now formed.