反应详情

To a solution of Compound 16a (2.12 g; 6.55 mmol) in AcOH (15 mL) and CH3OH (20 mL) was added Zn (2.57 g; 39.31 mmol) in portions at room temperature. The reaction mixture was stirred at room temperature for 6 h. The solid was collected by filtration and washed with CH3OH. The filtrate was concentrated. The residue was quenched with aqueous NaOH (<1 N) and adjusted to pH ˜7, and extracted with EtOAc (2×20 mL). The organic layer was dried over MgSO4 and concentrated. The crude product was purified by normal phase chromatography (SiO2) to give Compound 16b. 1H NMR (300 MHz, CDCl3): δ 8.15 (d, 2H), 7.95 (s, 1H), 7.25 (d, 2H), 4.45 (q, 2H), 1.4 (t, 3H); MS: m/z 294.1 (M+H)+.

1. filtrationThe solid was collected by filtration
2. washwashed with CH3OH
3. concentrationThe filtrate was concentrated
4. customThe residue was quenched with aqueous NaOH (<1 N)
5. extractionextracted with EtOAc (2×20 mL)
6. dry with materialThe organic layer was dried over MgSO4
7. concentrationconcentrated
8. customThe crude product was purified by normal phase chromatography (SiO2)