反应详情

To a solution of 109a (5.0 g, 20 mmol) in ethyl acetate (100 mL) was added SnCl2.2H2O (22.6 g, 100 mmol). The reaction was heated at reflux for 2 h. After cooled to room temperature, the reaction mixture was poured into aqueous Na2CO3 (200 mL) and the mixture was extracted with ethyl acetate (200 mL×3). The combined organic phase was dried over anhydrous Na2SO4, filtered, and evaporated under reduced pressure to afford 109b as a dark red liquid (4.3 g, 97%). LCMS: [M+H]+ 223. 1H NMR (500 MHz, CDCl3) δ 6.97 (d, J=2.5 Hz, 1H), 6.65 (d, J=2.5 Hz, 1H), 3.67 (bs, 4H).

1. temperatureThe reaction was heated
2. temperatureat reflux for 2 h
3. extractionthe mixture was extracted with ethyl acetate (200 mL×3)
4. dry with materialThe combined organic phase was dried over anhydrous Na2SO4
5. filtrationfiltered
6. customevaporated under reduced pressure