反应详情

To a solution of ethyl 2,2-difluoro-2-(4-fluoronaphthyl)acetate (9.6 g, 35.8 mmol), as prepared in the preceding step, in methanol (20 mL) and THF (20 mL) was added a solution of NaOH (2.0 g, 50 mmol) in water (40 mL). The reaction mixture was stirred at room temperature for 2 hours. After evaporating the methanol and THF in vacuo, the aqueous phase was acidified to pH 2 using 10% HCl, and extracted with DCM (3×50 mL). The extracts were combined, washed with brine, dried over Na2SO4, and concentrated to give the title compound (8.1 g, 94% yield) as an off white solid. 1H-NMR (400 MHz, CDCl3) δ 9.68 (br s, 1H), 8.18 (m, 2H), 7.83 (dd, J=8.1, 5.3 Hz, 1H), 7.62 (m, 2H), 7.19 (t, J=8.3 Hz, 1H).

1. customAfter evaporating the methanol and THF in vacuo
2. extractionextracted with DCM (3×50 mL)
3. washwashed with brine
4. dry with materialdried over Na2SO4
5. concentrationconcentrated