反应详情

To a solution of 6-chloro-5-methoxynicotinic acid methyl ester (1.3 g, 6.4 mmol) in MeOH (4 mL) at 25° C. was added 10% NaOH aqueous solution (19.3 mmol). The reaction was stirred for 24 h, then placed into an ice water bath and acidified with 2M HCl until pH=2 was achieved. The flask was then placed into a refrigerator for 3 h. The white precipitate was filtered off and rinsed with cold H2O. The solid was dissolved in acetone, dried over MgSO4 and concentrated to furnish the product 6-chloro-5-methoxynicotinic acid as a yellow solid (0.895 g, 74%); 1H NMR (400 MHz, CDCl3) δ 8.45 (d, 1H), 7.66 (d, 1H), 3.83 (s, 3H).

1. customplaced into an ice water bath
2. waitThe flask was then placed into a refrigerator for 3 h
3. filtrationThe white precipitate was filtered off
4. washrinsed with cold H2O
5. dissolutionThe solid was dissolved in acetone
6. dry with materialdried over MgSO4
7. concentrationconcentrated