Diacylation of coumarins by silver-catalyzed decarboxylative cross-coupling

A mild silver-catalyzed decarboxylative acylation of coumarins has been developed by using α-oxocarboxylic acids as acyl sources. This protocol provides an efficient and straightforward access to aroyl substituted coumarins in moderate to excellent yields with good selectivities. Furthermore, the reaction conditions were also applicable to quinolinones and naphthoquinones, affording the corresponding acylated heterocyclic compounds.