A mixture of ethyl 5-bromo-1,4-dimethyl-1H-pyrrole-3-carboxylate (246 mg, 1.0 mmol), 4-fluorophenyl-boronic acid (210 mg, 1.5 mmol), Na2CO3 (320 mg, 3.0 mmol) and Pd(PPh3)4 (116 mg, 0.10 mmol) in DMF/H2O (10:1, 10 mL) was sparged with nitrogen for 10 min. The reaction vial was sealed and heated at 110° C. with stirring. After 18h, the reaction mixture was diluted with DCM and then filtered. The filtrate was concentrated under reduced pressure and then purified by column chromatography, eluting with EtOAc-Hex (0:100 to 50:50), to give 1,4-dimethyl-5-(4-fluorophenyl)-1H-pyrrole-3-carboxylic acid ethyl ester (252 mg, 96%) as a pale yellow solid. 1H-NMR (CDCl3): δ 7.30 (1H, s), 7.26-7.20 (2H, m), 7.15-7.10 (2H, m), 4.28 (2H, q), 3.48 (3H, s), 2.20 (3H, s), 1.36 (3H, t). MS (ESI): 262 (MH+).
