反应详情

温度

-5 °C

Thionyl chloride (0.15 g, 1.30 mmol) was added slowly to a solution of 2-fluoro-4-nitrobenzoic acid (Formula 37) (0.20 g, 1.10 mmol) in DMF (5 mL) cooled at −5° C. The mixture was stirred for an additional 1 hour at −5° C. Excess methylamine (freshly distilled from its 40% aqueous solution) was added to the reaction medium. The second mixture was stirred for an additional 1 hour. Ethyl acetate (50 mL) was added to the mixture, which was washed with brine (2×50 ml). The organic layer was dried over MgSO4, and concentrated to yield N-Methyl-2-fluoro-4-nitrobenzamide (Formula 38) (0.18 g, 85%) as a yellowish solid. 1H NMR (acetone-d6) δ 3.05 (d, 3H, J=4.3), 6.31 (dd, 1H, J=13.5 and 2.1), 6.40 (dd, 1H, J=8.6 and 2.1), 7.64 (dd, 1H, J=8.6 and 8.6).

1. distillationExcess methylamine (freshly distilled from its 40% aqueous solution)
2. additionwas added to the reaction medium
3. stirringThe second mixture was stirred for an additional 1 hour
4. additionEthyl acetate (50 mL) was added to the mixture, which
5. washwas washed with brine (2×50 ml)
6. dry with materialThe organic layer was dried over MgSO4
7. concentrationconcentrated