To a stirred solution of oxazole ((0.28 mL, 4.2 mmol) in THF (10 mL) at −78° C. was added nBuLi (2.8 mL 1.6 N solution in hexane, 4.4 mmol). ZnCl2 (20 mL 0.5M soln, 10 mmol) was added after 30 min and the reaction mixture was warmed up to 0° C. for 1 h. To the resulting mixture was added dimethyl 5-iodoisophthalate (1.28 g, 4.0 mmol) and Pd(PPh3)4 and was heated at reflux for 5 h. The reaction mixture was cooled to room temperature and diluted with EtOAc and H2O. The layers were separated and the organic layer was washed with, brine, dried with Na2SO4 and concentrated under reduced pressure. The residue was purified by column chromatography (20% EtOAc in hexanes) to provide dimethyl 5-(oxazol-2-yl)isophthalate (568 mg, 54%).
