Visible-Light-Induced Esterification of Carboxylic Acids with Arylsulfonium Salts

A photoinduced copper-mediated acyloxylation of arylthianthrenium or arylphenoxathiinium salts with either aliphatic or aromatic carboxylic acids is described for the convenient synthesis of <i>O</i>-aryl esters. The reaction has shown obvious advantages, such as high efficiency, good functional group tolerance, excellent chemoselectivity, and capacity for esterification of complex drug molecules, offering a practical synthetic route to multifunctionalized and sterically congested <i>O</i>-aryl esters, which are potentially useful in the development of new prodrugs or twin drugs.