Photogeneration of Chlorine Radical from a Self‐Assembled Fluorous 4CzIPN•Chloride Complex: Application in C−H Bond Functionalization

Abstract

AbstractThe chlorine radical is a strong HAT (Hydrogen Atom Transfer) agent that is very useful for the functionalization of C(sp3)−H bonds. Albeit highly attractive, its generation from the poorly oxidizable chloride ion mediated by an excited photoredox catalyst is a difficult task. We now report that 8Rf8‐4CzIPN, an electron‐deficient fluorous derivative of the benchmark 4CzIPN photoredox catalyst belonging to the donor‐acceptor carbazole‐cyanoarene family, is not only a better photooxidant than 4CzIPN, but also becomes an excellent host for the chloride ion. Combining these two properties ultimately makes the self‐assembled 8Rf8‐4CzIPN•Cl− dual catalyst highly reactive in redox‐neutral Giese‐type C(sp3)−H bond alkylation reactions promoted by the chlorine radical. Additionally, because of its fluorous character, the efficient separation/recovery of 8Rf8‐4CzIPN could be envisioned.