Chlorotrifluoromethylation of Terminal Olefins by Atom Transfer‐Type Radical Reaction Catalyzed by Cobalt Complexes

A cobalt porphyrin‐catalyzed chlorotrifluoromethylation reaction of olefins is described. The use of CF3SO2Cl as the CF3 radical source and a cobalt catalyst enabled the selective addition of CF3 radicals under thermal conditions. Various functional groups such as esters and Ar–X moieties, which can be reactive with low valent transition metal catalysts, were well‐tolerated in this catalytic process. A highly functionalized alkaloid derivative was also tolerated as a substrate. As a demonstration of the bio‐inspired catalytic system, catalytic usage of vitamin B12, which is the commercially available form of the natural cobalt porphyrinoid, was employed, and diastereoselective chlorotrifluoromethylation of the alkaloid molecule was achieved. A cobalt porphyrin‐catalyzed chlorotrifluoromethylation reaction of olefins is described. The use of CF3SO2Cl as the CF3 radical source and a cobalt catalyst enabled the selective addition of CF3 radicals under thermal conditions.