Scheme 3. AuBr₃-catalyzed directed C–H arylation of arenes with arylboronic acids. Reaction conditions: biaryl or biaryl ether (0.2 mmol), arylboronic acid (3.0 equiv.), gold(iii) bromide (5 mol%), and NFSI (3.0 equiv.) in t-BuOH (2 mL) at 130 °C under N₂ for 24 h. ^aAt 140 °C.