To a solution comprised of 2-(4-iodo-2-methyl-phenylamino)-3,4,5-trifluoro-benzoic acid (3.60 g, 8.84 mmol), O-(2-vinyloxyethyl)hydroxylamine (1.09 g, 10.5 mol) and diisopropylethylamine (2.80 mL, 16.0 mmol) in dichloromethane (50 mL) was added benzotriazole-1-yl-oxy-tris-pyrrolidino-phosphonium-hexafluorophosphate (5.26 g, 10.1 mmol). The resultant solution was stirred 90 min at ambient temperature. The reaction mixture was diluted with ether (100 mL) and washed with water (3×50 mL) and saturated brine (50 mL). The organics were dried over anhydrous magnesium sulfate and concentrated in vacuo. The residue was purified by silica gel chromatography to afford 2-(4-iodo-2-methyl-phenylamino)-3,4,5-trifluoro-N-(2-vinyloxyethoxy)benzamide (3.17 g, 73%) as a pale-yellow foam.
