反应详情

Alcohol of step A (higher Rf isomer, 0.290 g, 1.11 mmol) was dissolved in THF (10 mL) under nitrogen. Hydrochloric acid (2.0 mL, 4.0 M aqueous solution, 8.0 mmol) was added and the mixture stirred for 4 hours at room temperature. The mixture was then diluted with NaHCO3/H2O and extracted twice with ethyl acetate. The extracts were washed with brine, dried over MgSO4, filtered and concentrated to provide a light yellow solid, 0.204 g (85%). The crude product 2 was used directly for the next step without further purification. 1H NMR (CDCl3) □δ□□ 8.74 (s, 1H), 8.52 (d, 1H), 7.72 (dt, 1H), 7.30 (dd, 1H), 2.66 (dt, 1H), 2.53 (m, 2H), 2.41 (t, 1H), 2.18 (t, 1H), 2.13 (d, 1H), 2.09 (m, 1H), 1.99 (m, 1H), 1.89 (m, 1), 1.62 (m, 2H). Step C

1. extractionextracted twice with ethyl acetate
2. washThe extracts were washed with brine
3. dry with materialdried over MgSO4
4. filtrationfiltered
5. concentrationconcentrated
6. customto provide a light yellow solid, 0.204 g (85%)
7. customThe crude product 2 was used directly for the next step without further purification