1-Bromo-5-fluoro-2-methoxy-3-nitro-benzene 2c (16.18 g, 64.7 mmol), 3-carboxyphenylboronic acid (13.88 g, 77.7 mmol) and tetrakis(triphenylphosphine)palladium (3.73 g, 3.2 mmol) were dissolved in the solvent mixture of 65 mL of aqueous sodium carbonate (2 N) and 300 mL of 1,4-dioxane. The reaction mixture was heated to reflux at 120° C. for 24 hours. The reaction was monitored by TLC until the disappearance of the starting materials. The mixture was concentrated under reduced pressure and diluted with 150 mL of hydrochloric acid (6 N) and 200 mL of ethyl acetate. The aqueous layer was extracted with ethyl acetate (100 mL×2). The combined organic extracts were dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to obtain the title compound 5′-fluoro-2′-methoxy-3′-nitro-biphenyl-3-carboxylic acid 2d (7.86 g, yield 41.7%) as a yellow solid.
