Copper-catalyzed trifluoromethylation-initiated radical 1,2-aryl migration in α,α-diaryl allylic alcohols

Not only symmetrical, but also unsymmetrical α,α-diaryl allylic alcohols are employed as substrates in the title reaction. A number of arenes and even heteroarenes underwent radical 1,2-aryl migration ("neophyl rearrangement") to produce α-aryl β-trifluoromethyl ketones. The preferential migration of electron-deficient aryl groups over electron-rich ones in unsymmetrical substrates supports the radical mechanism, which was further confirmed by DFT calculations.