反应详情

Triisopropylsilane (0.058 mL, 0.28 mmol), trifluoroacetic acid (TFA, 0.2 mL) and water (0.02 mL) were added to a solution of 56 (0.093 g, 0.14 mmol) in CH2Cl2 (2 mL). After string for 15 minutes, the pH of the mixture was adjusted to pH 7-8 with saturated aqueous NaHCO3 and product was extracted with CH2Cl2 twice. The combined organic solutions was dried (MgSO4) and concentrated to afford a tan syrup. Hexane:AcOEt (1:1) solution of was added to the syrup and the mixture was cooled with ice-water bath. The precipitate was filtered off, washed with hexane and dried to afford 57 (0.037 g, 63%) as a brown solid. 1H NMR (400 MHz, CDCl3) δ 3.06-3.10 (m, 4H), 3.80-3.84 (m, 4H), 7.34 (d, J=0.27 Hz, 1H), 7.39-7.44 (m, 2H), 7.48-7.53 (m, 1H), 7.68 (s, 1H), 7.79 (bs, 1H), 8.09-8.13 (m, 2H), 8.18 (d, J=0.27 Hz, 1H).

1. extractionwas extracted with CH2Cl2 twice
2. dry with materialThe combined organic solutions was dried (MgSO4)
3. concentrationconcentrated
4. customto afford a tan syrup
5. temperaturethe mixture was cooled with ice-water bath
6. filtrationThe precipitate was filtered off
7. washwashed with hexane
8. customdried