反应详情

温度

-78 °C

To a cooled (−78° C.) solution of the title compound of Example 1 Step A (ca. 42.6 mmol) in THF (100 mL) was added n-hexyllithium (74 mL, 2.3 M in hexanes, 170.4 mmol) dropwise. The mixture was stirred at −78° C. for 2 h, then was quenched by addition of 2 N aqueous hydrochloric acid. The resulting suspension was allowed to warm to room temperature, then was extracted with ethyl acetate. The organic phase was concentrated in vacuo. Purification by flash chromatography on silica gel (10% EtOAc in hexanes) provided the title compound: LCMS B, tr=2.70 min, m/z 264.2 [M+H]+; 1H NMR (500 MHz, CDCl3) δ 9.37 (br s, 1H), 7.68 (d, J=2.0 Hz, 1H), 7.37 (d, J=9.0 Hz, 1H), 7.29 (dd, J=9.0, 2.0 Hz, 1H), 7.13 (s, 1H), 2.94 (t, J=7.5 Hz, 2H), 1.78 (quint., J=7.5 Hz, 2H), 1.43-1.29 (m, 6H), 0.89 (t, J=7.0 Hz, 3H).

1. customwas quenched by addition of 2 N aqueous hydrochloric acid
2. temperatureto warm to room temperature
3. extractionwas extracted with ethyl acetate
4. concentrationThe organic phase was concentrated in vacuo
5. customPurification by flash chromatography on silica gel (10% EtOAc in hexanes)