Rhodium-Catalyzed ortho-Arylation of (Hetero)aromatic Acids

Rhodium acetate effectively promotes the carboxylate-directed ortho-arylation of (hetero)aromatic carboxylates with aryl bromides. The main advantage of this phosphine-free, redox-neutral method arises from its efficiency in assembling biologically meaningful electron-rich arylpyridines, which are problematic substrates in known C-H arylations using Pd, Ru, and Ir catalysts.