Sulphamic acid - An efficient and cost-effective solid acid catalyst for the Pechmann reaction

Sulphamic acid (H2NSO3H, SA) is used as an alternative to conventional acid catalysts in the Pechmann condensation of phenols with beta-ketoester leading to the formation of substituted coumarin. The method is simple, cost-effective, solvent-free and gives good yields in a short reaction time.