An in situ generated proton initiated aromatic fluoroalkylation via electron donor–acceptor complex photoactivation

Abstract

The photoactivation of electron donor–acceptor complexes to obtain fluoroalkyl arenes provides an economical and environment-friendly means of directly installing fluoroalkyl groups (–CF₂H, –CF₃, –C₄F₉, –C₆F₁₃, etc.) in late-stage drug discovery. However, recent progress in the field has been constrained to the use of electron-rich arenes as electron donors due to their inherent electronic properties. In comparison, the role reversal strategy of using commercial fluoroalkyl reagents as donors and various aromatic substrates as acceptors remains an unexplored frontier. Herein, we proposed a photoactivation of electron donor–acceptor (EDA) complexes between fluoroalkyl sulfonates (donors) and in situ-generated protonated aromatic hydrocarbons (catalytic acceptors) to achieve the C–H fluoroalkylation and tandem cyclization/fluoroalkylation of more than 80 (hetero)arenes. The process relies on available reagents, avoiding the need for metals, exogenous photocatalysts, and additives.