反应详情

LiHMDS (1.0 M in THF, 13 ml, 13 mmol) was added slowly via syringe to a solution of Example 45B (3.04 g, 11.6 mmol) in THF (50 mL) at −78° C. The solution was stirred 45 min, and then solid hexachloroethane (4.13 g, 17.4 mmol) was added in one portion. The reaction was allowed to proceed for 12 hr with gradual warming to ambient temperature. The reaction was quenched with half-saturated aq NH4Cl solution, and the product was extracted with Et2O. The combined organic extract was washed with brine, dried (Na2SO4), filtered, and concentrated in vacuo. The crude product was purified by flash chromatography (Analogix® Intelliflash 280™; 0% to 20% EtOAc/hexanes eluant; SF40-150 g column) to afford 3.02 g (88%) of the title compound as a white solid. 1H NMR (300 MHz, DMSO-d6) δ 7.97 (d, J=8.4, 1H), 7.86 (s, 1H), 7.75 (d, J=8.3, 1H), 2.42 (s, 3H). MS (DCI+) m/z 296 (M+H).

1. waitto proceed for 12 hr
2. customThe reaction was quenched with half-saturated aq NH4Cl solution
3. extractionthe product was extracted with Et2O
4. extractionThe combined organic extract
5. washwas washed with brine
6. dry with materialdried (Na2SO4)
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe crude product was purified by flash chromatography (Analogix® Intelliflash 280™