A mixture of 4-trifluoromethoxybenzeneboronic acid (0.4 g, 1.1 mmol), 3-(2-chloro-6-fluorophenyl)-5-[5-bromo-4-methylthien-3-yl]-1-methyl-1H-1,2,4-triazole (0.4 g, 1 mmol), sodium carbonate (0.2 g, 1.9 mmol), tri-o-tolylphosphine (32 mg, 0.1 mmol) and dichlorobis(triphenylphosphine)palladium(II) (73 mg, 0.1 mmol) were refluxed under nitrogen for 16 hours in an acetonitrile (14 mL) and water (1.4 mL) solution. After cooling to room temperature, the reactants were poured into dilute hydrochloric acid (1 N, 50 mL) and extracted with ether (3×50 mL). The combined ethereal extracts were washed with water (100 mL), saturated aqueous bicarbonate (70 mL) and brine (50 mL), dried over magnesium sulphate, filtered and concentrated. The residue was chromatographed over silica to afford the product as a yellow gum (210 mg, 43%): 1H NMR (CDCl3) δ 7.55 (s, 1H), 7.49 (d, 2H), 7.28-7.39 (m, 4H), 7.11 (t, 1H), 4.03 (s, 3H), 2.33 (s, 3H); EI/MS 467 m/e (M−1).
