Sulphamic acid (H2NSO3H, SA) is used as an alternative to conventional acid catalysts in the Pechmann condensation of phenols with β-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.
Substituted coumarins were synthesized in good yields via the Pechmann reaction in chloroaluminateionicliquid. 1-Bu-tylpyridinium chloroaluminateionicliquid was used as a solvent cum catalyst for this condensation reaction.
Selectfluor™: A simple and efficient catalyst for the synthesis of substituted coumarins under solvent-free conditions
作者:B. Sunil Kumar、Y. Thirupathi Reddy、P. Narsimha Reddy、P. S. Kumar、B. Rajitha
DOI:10.1002/jhet.5570430233
日期:2006.3
Selectfluor™ is used as an alternative catalyst to conventional catalysts for the synthesis of substitutedcoumarins via Pechmann condensation of phenols with β-ketoesters undersolvent-freeconditions at 120 °C. This method of synthesis is simple, cost-effective, requires short reaction time, solvent-free and gives good yields.
Alum (KAl(SO4)2 · 12H2O) is used as an efficient catalyst in the Pechmann condensation of phenol derivatives with β-keto esters leading to the formation of coumarins in excellent yields undersolvent-freeconditions. This methodology offers significant improvements for the synthesis of coumarins with regard to the yield of products, simplicity in operation, and green aspects by avoiding toxic catalysts