A mixture of 2-bromo-4-hydroxybenzaldehyde (350 mg, 1.74 mmol), phenyl boronic acid (233.5 mg, 1.92 mmol), Pd(PPh3)4 (60 mg, 0.052 mmol), saturated sodium bicarbonate (6.0 mL), methanol (15 mL), and toluene (6.0 mL) was heated in a pressure tube at 120° C. overnight. Ethyl acetate and water were added and the layers separated. The aqueous phase was extracted with ethyl acetate and the combined organic layers were dried over sodium sulfate, filtered and concentrated in vacuo. The crude compound was purified by flash column chromatography on silica gel with hexanes and EtOAc (30%) to afford 5-hydroxy-[1,1′-biphenyl]-2-carbaldehyde (651).
