Pd-Catalyzed Hydroxylation of Aryl Halides under Air and in Eco-Friendly Solvent

A Pd-catalyzed synthesis of phenols in 10% aqueous poly-(ethylene glycol)-2000 (PEG) under an air atmosphere is reported. The reaction proceeds with NaOH as opposed to other BippyPhos/Pd systems in organic solvents that rely on more expensive and reactive CsOH. The reported method converts aryl chlorides, bromides, and iodides with a variety of functional groups at 90 °C to the corresponding phenols in moderate to excellent yields. Due to the aerobic atmosphere, these conditions also oxidize benzyl alcohol substituents to the corresponding aldehyde.