Insight into the mechanism of platinum-catalyzed cross-coupling of polyfluoroaryl imines

We recently reported the first examples of Pt-catalyzed methylation of polyfluorinated arenes as a means to generate partially fluorinated aromatic building blocks. The reaction is selective for cleavage of C-F bonds ortho to an imine substituent and allows for preferential cleavage of C-F bonds in the presence of considerably weaker bonds (e.g., C-Br). We report herein the proposed mechanism for this reaction. Initial C-F activation generates a Pt(IV)-F intermediate, which then reacts with (CH(3))(2)Zn via transmetalation. Subsequent reductive elimination from the Pt(IV) species generates a new sp(2)-sp(3) C-C bond. In addition, we have identified a species present during the catalytic reaction and propose this to be the catalyst resting state.