[Li+].C[Si]([N-][Si](C)(C)C)(C)C.[CH2:11]([C:13]1[N:14]=[CH:15][O:16][C:17]=1[C:18]1[CH:23]=[CH:22][C:21]([C:24]([F:27])([F:26])[F:25])=[CH:20][CH:19]=1)[CH3:12].[Cl:28]C(Cl)(Cl)C(Cl)(Cl)Cl>C1COCC1>[Cl:28][C:15]1[O:16][C:17]([C:18]2[CH:19]=[CH:20][C:21]([C:24]([F:27])([F:26])[F:25])=[CH:22][CH:23]=2)=[C:13]([CH2:11][CH3:12])[N:14]=1LiHMDS (1.0 M in THF, 26 mL, 26 mmol) was added dropwise to a solution of Example 43A (5.75 g, 23.8 mmol) in THF (100 mL) at −78° C. After 30 min solid hexachloroethane (6.21 g, 26.2 mmol) was added in one portion, and the reaction mixture was allowed to proceed for 18 hr with gradual warming to ambient temperature. The reaction was quenched with saturated aq NH4Cl solution (50 mL), and the mixture was partitioned between H2O and Et2O. The aqueous phase was extracted once with Et2O, and the combined organic extract was washed with brine, dried (Na2SO4), filtered, and concentrated in vacuo. The crude product was purified on silica gel (Analogix® Intelliflash 280™; SF40-150 g column; 100% hexane 7 min, then 0% to 20% EtOAc/hexanes eluant, 23 min) which yielded 6.23 g (95%) of the title compound as a pale yellow oil. 1H NMR (300 MHz, DMSO-d6) δ 7.87 (d, J=8.5, 2H), 7.79 (d, J=8.5, 2H), 2.77 (q, J=7.5, 2H), 1.23 (t, J=7.5, 3H). MS (DCI+) m/z 276 (M+H).
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