To a stirred solution of (E)-2-bromo-4-(4,4,4-trifluoro-3-(3,4,5-trichlorophenyl)but-1-enyl)benzoic acid (600 mg, 1.23 mmol) in dry toluene (10 mL) was added tributyl(vinyl)stannane (470 mg, 1.48 mmol) and the mixture was degassed with argon for 15 min Pd(PPh3)4 (72 mg, 0.06 mmol) was added and the reaction mixture was refluxed for 2 h. The reaction mixture was brought to ambient temperature, water was added and the mixture extracted with EtOAc. The organic layer was washed with 2N HCl and brine, dried (Na2SO4), filtered, and concentrated. The residue was purified by column chromatography on silica eluting with 30% EtOAc in petroleum ether to afford the title compound as brown solid (295 mg, 55%): 1H NMR (300 MHz, DMSO-d6) δ 13.05 (bs, 1H), 7.91 (s, 2H), 7.81-7.75 (m, 2H), 7.59 (d, J=8.1 Hz, 1H), 7.48 (dd, J=17.4, 10.8 Hz, 1H), 7.03 (dd, J=15.9, 8.7 Hz, 1H), 6.84 (d, J=15.6 Hz, 1H), 5.88 (d, J=16.5 Hz, 1H), 5.39 (d, J=12.3 Hz, 1H), 4.89-4.82 (m, 1H); ESIMS m/z 432.18 ([M−H]−); IR (thinfilm) 3418, 1689, 1114, 747 cm−1.
