Graphitic Carbon Nitride as a Metal-Free Heterogeneous Semiconductor Photocatalyst for Fluoroalkylation Reactions

The increasing use of fluorine-containing bioactive molecules necessitates efficient strategies for fluorinated group installation. Despite the impressive development of photoinduced radical fluoroalkylation as a powerful tool for introducing fluorine, the persistent issues, including the recyclability and reaction specificity of homogeneous photocatalysts, still leave great room for further advancement in a sustainable and general fashion. Herein, we report a conceptually different approach toward multiple types of fluoroalkylations by using recoverable and versatile graphitic carbon nitride (g-CN) nanosheets as a heterogeneous photocatalyst. This photocatalytic system enables diverse intermolecular fluoroalkylations of alkenes with fluoroalkanesulfinates and intramolecular fluoroalkyl migrations of alkenyl triflates. Detailed characterizations and mechanism studies substantiate the stability of this organic semiconductor and the crucial role of photogenerated electron-hole pairs. In this article, we describe a stable semiconductor material, g-CN nanosheets, can serve as a heterogeneous photocatalyst to accomplish intermolecular fluoroalkylation of assorted alkenes with fluoroalkanesulfinates and intramolecular fluoroalkyl migration of alkenyl triflates. The inexpensive and easy-prepared g-CN nanosheets can be recycled for several runs with conserved activity.+ image