Carbonylative Transformations of Aryl Sulfonium Salts

Carbonyl derivatives are widely present in biologically active molecules, pharmaceuticals, natural products, and materials, and their synthesis has garnered much attention. Hence, developing new, efficient, and environmentally friendly methods for synthesizing carbonylated compounds is one of the core research projects in the field of organic synthesis. In carbonylation reactions, direct carbonylation of aromatic CH bonds is an effective tool for the synthesis of carbonyl compounds. Yet, the selective carbonylation of CH bonds of aromatic hydrocarbons remains an important challenge as multiple CH bonds of a molecule have similar electronic properties and steric environments. In this regard, aryl sulfonium salts, as active reagents that can be involved in various synthetic reactions, provide an attractive solution to this challenge. In this review, the recent advances in the site‐selective carbonylation transformation of arenes via aryl sulfonium salts, as well as their reaction mechanisms and synthetic applications are summarized and discussed systematically.