Phenol Derivatives: Modern Electrophiles in Cross-Coupling Reactions

In recent years, C–O electrophiles have emerged as powerful alternatives to organic halides, common counterparts in metal-catalyzed cross-coupling reactions. Among their advantages are their low toxicity, ready availability, the natural abundance of phenols, and their pivotal role as synthons in organic synthesis, which makes them particularly attractive vehicles for further functionalization. This review summarizes the most important developments in cross-coupling reactions via catalytic C–O bond activation of particularly unreactive aryl esters, carbamates, and aryl ethers, providing a general overview of the current state of the art and including mechanistic implications as well as future aspects, when appropriate.