To a solution containing (E)-2-bromo-4-(4,4,4-trifluoro-3-(3,4,5-trichlorophenyl)but-1-en-1-yl)benzoic acid (120 mg, 0.246 mmol), 1,2-dichloroethane (DCE) (5 mL) was added sequentially EDC.HCl (70.6 mg, 0.368 mmol), N-(2,2,2-trifluoroethyl)hydrazinecarboxamide hydrochloride (52.3 mg, 0.270 mmol) and DMAP (63.0 mg, 0.516 mmol). The reaction mixture was stirred at ambient temperature for 18 h. The reaction mixture was diluted with CH2Cl2, washed with 0.1N HCl then with aqueous NaHCO3, dried (MgSO4), filtered and evaporated to dryness. The crude product was purified by flash column chromatography afford the title compound as a glassy oil (40 mg, 26%): 1H NMR (400 MHz, CDCl3) δ 8.12 (s, 1H), 7.65 (s, 1H), 7.60 (d, J=8.0 Hz, 1H), 7.51 (d, J=6.4 Hz, 1H), 7.40 (s, 3H), 6.54 (d, J=15.8 Hz, 1H), 6.42 (dd, J=16.0, 7.7 Hz, 1H), 5.95 (s, 1H), 4.10 (s, 1H), 3.91 (m, 2H); 19F NMR (376 MHz, CDCl3) δ −68.56, −73.02; ESIMS m/z 627.9 ([M+H]+).
