反应详情

A solution of lithium hydroxide (357 mg, 8.5 mmol, 4.0 equiv) and ethyl 4-(6-bromopyridin-3-yl)-2-methyl-2-(methylsulfonyl)butanoate (775 mg, 2.1 mmol, 1.0 equiv) in 1:1:1 tetrahydrofuran-methanol-water (3 mL) was allowed to stir at room temperature for 2 h. The reaction was diluted with water (150 mL), acidified (to pH=2) with 0.5 M hydrochloric acid, and then was extracted with ethyl acetate (3×100 mL). The combined organic layers were washed with brine (100 mL), dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to provide the title compound (716 mg, 98%). MS (LCMS) m/z 334.1 (M−1). 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 1.56 (s, 3H) 2.03 (td, J=12.78, 5.27 Hz, 1H) 2.31 (td, J=12.68, 4.68 Hz, 1H) 2.51 (td, J=12.98, 4.49 Hz, 1H) 2.59-2.70 (m, 1H) 2.96 (s, 3H) 7.30-7.39 (m, 2H) 8.07 (d, J=1.56 Hz, 1H).

1. extractionwas extracted with ethyl acetate (3×100 mL)
2. washThe combined organic layers were washed with brine (100 mL)
3. dry with materialdried over anhydrous sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure