Continuous activation of phenoxide and CF3I for multiple trifluoromethylations

Abstract

The introduction of multiple trifluoromethyl (CF₃) groups into aromatic compounds remains a significant challenge in synthetic chemistry. Here, we report an unprecedented visible light-promoted multiple trifluoromethylation of phenols using commercially available CF₃I. The key to success lies in our discovery of a “continuous activation strategy” that enables sequential trifluoromethylations through single-electron transfer from photoexcited phenoxide to CF₃I until all ortho or para positions are occupied. This practical method provides access to previously inaccessible multi-CF₃-substituted phenols under mild conditions, opening revolutionary possibilities for the design of fluorine-containing functional materials.