Photoredox-Neutral Ni-Catalyzed Decarboxylative Fluoroalkylation via Radical Sorting Cross-Coupling

The C(sp3/sp2)-C(sp3) linkages are undoubtedly important in modern organic synthesis. The number and variety of oxidative addition-driven photoredox neutral nickel-catalyzed C(sp3)-C(sp2) couplings have increased significantly in recent years. However, neutral radical–radical cross-coupling to form C(sp3/sp2)-C(sp3) bonds remains an important but elusive goal for engineering coupling reactions, especially in regulating cross-selectivity. In this article, we report an efficient photoredox-neutral Ni-catalyzed highly chemoselective decarboxylative fluoroalkylation via radical–radical cross-coupling of carboxylic acids and α-CF3 alkyl bromides. Detailed mechanistic studies elucidated the decarboxylation in an oxidative process that is orthogonal to α-CF3 alkyl bromide activation via oxidative addition, and radical sorting of two coupling partners with different electronic effects offers the possibility of tuning the rate of radical addition of the two radicals to achieve good cross-selectivity. A wide range of fluoroalkyl halides and carboxylic acids bearing a diverse set of substituents were compatible to produce valuable aliphatic CF3 chiral products under mild conditions.