反应详情

A mixture of tert-butyl 2-(6-chloro-5-methylpyridin-3-yl)acetate 86-6 (7.8 g, 32 mmol) and TFA (32 mL) in DCM (32 mL) was stirred at room temperature for 3 hours. The solution was adjusted to pH around 12 by sodium carbonate and extracted with dichloromethane. The aqueous phase was acidified to pH 3 by 1N HCl aqueous solution and stirred for 15 minutes. The suspension was extracted with dichloromethane (100 mL×3). The combined organic phases were washed with water and brine, dried over Na2SO4 and then dried to give 2-(6-chloro-5-methylpyridin-3-yl)acetic acid 86-7 as pale yellow solid. MS m/z 186.1 (M+1); 1H NMR 400 MHz (CD3Cl) δ 8.17 (d, 1H, J=2.0 Hz), 7.55 (d, 1H, J=2.0 Hz), 3.63 (s, 2H), 2.38 (s, 3H).

1. extractionextracted with dichloromethane
2. stirringstirred for 15 minutes
3. extractionThe suspension was extracted with dichloromethane (100 mL×3)
4. washThe combined organic phases were washed with water and brine
5. dry with materialdried over Na2SO4
6. customdried