To a stirred solution of 5-bromo-2-nitroaniline (10.3 g, 47.3 mmol, 1 eq.), thiophen-2-ylboronic acid (9.08 g, 70.9 mmol, 1.5 eq.) and tetrakis(triphenylphosphine)palladium(0) (5.46 g, 4.73 mmol, 0.1 eq.) in THF (150 mL) was added a solution of sodium carbonate (7.27 g, 68.6 mmol, 1.45 eq.) in water (15 mL). The resulting mixture was warmed to 90° C. for 18 h. The reaction was then diluted with EtOAc and water and filtered through Celite. The organic layer was separated and dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by column chromatography (silica gel, 2% EtOAc/hexanes) to afford 2-nitro-5-(thiophen-2-yl)aniline (12.0 g, 79% yield).
