Pechmann Reaction
Pechmann condensation discovered by Hans von Pechmann in 1883 is condensation of phenols with β-keto esters or carboxylic acids under acidic conditions to form coumarins. The acid catalysts used for the Pechmann condensation reaction are concentrated sulphuric acid, trifluoroacetic acid (TFA), phosphotungstic acid, TiCl4, P2O5, ZrCl4, Nafion resin, HClO4/SiO2, SnCl2·2H2O, zirconium phosphor-tungstate, deep eutectic solvents, ionic liquids, etc.
Mechanism of Pechmann Reaction
