Direct Synthesis of Coumarins by Pd(II)-Catalyzed Reaction of Alkoxyphenols and Alkynoates

Abstract
Reaction of alkoxyphenols and alkynoates in the presence of a catalytic amount of Pd(OAc)2 in trifluoroacetic acid at room temperature gave coumarin derivatives in high yields. This procedure provides a convenient method for direct synthesis of coumarin derivatives under very mild conditions.