Leveraging the Hydroarylation of α‑(Trifluoromethyl)styrenes to Access Trifluoromethylated All-Carbon Quaternary Centers

α-(Trifluoromethyl)­styrenes are attractive olefin building blocks that have eluded hydroarylation processes. Here, we demonstrate that the use of a promoter system featuring triflic acid and hexafluoroisopropanol enables hydroarylation to directly build trifluoromethylated all-carbon quaternary centers. The observed reactivity significantly enriches the scope of hydroarylation of unactivated styrenes and provides straightforward access to trifluoromethylated diarylalkanes of interest. Gram-scale reactions and further functionalizations illustrate the synthetic potential of this approach.