(Kolbe-Schmitt synthesis), a method of synthesizing aromatic o-hydroxycarboxylic acids by the action of CO2 on the alkaline salt of the corresponding phenol:

The Kolbe-Schmitt reaction serves as the basis for industrial methods of producing salicylic acid from phenol, p-aminosalicylic acid (PASA) from m-aminophenol, and β-hydroxynaphthoic acid from β-hydroxynaphthol. The reaction was developed by the German chemist A. W. H. Kolbe in 1860 and improved by the German chemist R. Schmitt in 1865.