反应详情

To a cloudy mixture of 3-bromo-2-chloro-5-nitropyridine (Atlantic Scitech, Linden, N.J., 5.10 g, 21.48 mmol) in 50 mL anhydrous methanol at 0° C. (ice/water bath) was added sodium methoxide 5.4 M in methanol (7.96 mL, 43.0 mmol) dropwise by addition funnel. The reaction became clear then a thick precipitate formed. The ice/water bath was removed and the reaction warmed to ambient temperature, quenched with water and sat'd aq. NH4Cl and DCM. The aqueous layer was extracted with DCM 2 times, and the combined organics were dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to give 3-bromo-2-methoxy-5-nitropyridine (5.07 g, 21.76 mmol, quantitative yield) as a light yellow solid. m/z (ESI, +ve ion) 233 (M+H)+. 1H NMR (400 MHz, CDCl3) δ 9.02 (d, J=2.3 Hz, 1H), 8.63 (d, J=2.5 Hz, 1H), 4.15 (s, 3H).

1. additiondropwise by addition funnel
2. customa thick precipitate formed
3. customThe ice/water bath was removed
4. customquenched with water
5. extractionThe aqueous layer was extracted with DCM 2 times
6. dry with materialthe combined organics were dried over anhydrous sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated in vacuo