反应详情

温度

70 °C

To a solution of compound 202b (70 g, 1 eq.) in tBuOH (1.2 L) was added potassium t-butoxide (46 g, 2.1 eq.) under nitrogen. The mixture was heated to 70° C. for 16 hrs. The reaction mixture was concentrated under reduced pressure and then acidified to pH 5. The precipitate was filtered, washed with water, and triturated in a diisopropylether/pentane mixture to yield compound 203b as a beige solid in 89% yield. 1H NMR (CDCl3, 400 MHz) δ (ppm) 2.43 (s, 3H), 3.98 (s, 3H), 6.76 (d, J=1.76 Hz, 1H), 7.04 (d, J=9.10 Hz, 1H), 7.96 (s, 1H), 8.24 (d, J=9.10 Hz, 1H), 9.31 (brs, 1H).

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. filtrationThe precipitate was filtered
3. washwashed with water
4. customtriturated in a diisopropylether/pentane mixture