To a solution of 5-bromo-2,3-dimethylbenzoic acid (500 mg, 2.18 mmol, 1.0 eq), (3,5-difluorophenyl)boronic acid (414 mg, 2.62 mmol, 1.2 eq) and Na2CO3 (925 mg, 8.73 mmol, 4.0 eq) in a mixture of EtOH (5 mL), DMF (20 mL) and water (5 mL) was added Pd(PPh3)4 (252 mg, 0.22 mmol, 0.1 eq) under nitrogen. The mixture was stirred at 100° C. overnight. Water was added and the mixture acidified to pH 3 by addition of 3M HCl. The aqueous layer was extracted with EtOAc and the combined organic extracts were washed with water and brine, dried (Na2SO4), filtered and evaporated in vacuo. The residue was purified by column chromatography (CH2Cl2:MeOH, 300:1 to 200:1) to give the title compound as a white solid (184 mg, 32%).
