To a solution of 5-bromo-2,3-dimethyl-benzoic acid (690 mg, 3.0 mmol, 1.0 eq), phenylboronic acid (404 mg, 3.3 mmol, 1.1 eq) and Na2CO3 (958 mg, 9.0 mmol, 3.0 eq) in a mixture of EtOH (5 mL), DMF (20 mL) and water (5 mL) was added Pd(PPh3)4 (0.17 g, 0.15 mmol, 0.05 eq). The reaction was heated at 100° C. overnight then diluted with EtOAc and filtered through celite. The aqueous layer was acidified to pH 4-5 with diluted HCl and extracted with EtOAc. The combined organic extracts were washed with water and brine, dried (Na2SO4), filtered and evaporated in vacuo. The residue obtained was purified by column chromatography (petroleum ether:EtOAc, 10:1 then CH2Cl2:MeOH, 400:0 to 20:1) to give the title compound as a white solid (315 mg, 46%).
