Synthesis of 7-alkoxy-4-trifluoromethylcoumarins via the von Pechmann reaction catalyzed by molecular iodine

The synthesis of a series of 7-alkoxy-4-trifluoromethylcoumarins via the von Pechmann reaction catalyzed by molecular iodine is described. The reaction protocol is simple, inexpensive and leads to the formation of the corresponding coumarin derivatives in good yield and high purity. A key intermediate as well as several iodo byproducts were isolated.