反应详情

A 100-mL single-neck round-bottomed flask was charged with 115b (190 mg, 0.35 mol) in THF/iPA/H2O (5 mL/5 mL/2 mL) and LiOH (85 mg, 3.5 mmol) while stirring. This mixture was stirred at 50° C. for 0.5 h. Then 20 mL H2O was added and the mixture was extracted with EA (30 mL×3). The combined organic layer was dried over Na2SO4 and concentrated to give a yellow solid, which was further purified by reverse-phase prep-HPLC to afford 115 as a white solid (48 mg, 30% yield). LCMS: [M+H]+ 500. 1H NMR (500 MHz, CDCl3) δ 8.44 (d, J=6.0, 1H), 7.95 (s, 1H), 7.69 (s, 1H), 7.44 (s, 1H), 7.30 (d, J=6.0, 2H), 6.87 (s, 1H), 5.74 (s, 1H), 4.59-3.86 (m, 7H), 3.69 (s, 3H), 2.57-2.56 (m, 4H), 2.25 (s, 3H) 1.88-1.77 (m, 4H)

1. stirringThis mixture was stirred at 50° C. for 0.5 h
2. extractionthe mixture was extracted with EA (30 mL×3)
3. dry with materialThe combined organic layer was dried over Na2SO4
4. concentrationconcentrated
5. customto give a yellow solid, which
6. customwas further purified by reverse-phase prep-HPLC