反应详情

To a solution of 2,4-difluoro-5-aminobenzoic acid (1.73 g, 10.0 mmol) in DMF (40 mL) were successively added EDCI (1.62 g, 12.0 mmol), HOBt (2.30 g, 12.0 mmol) and methylamine (6.0 mL, 12.0 mmol, 2 M in MeOH) in that order at RT. After stirring for 2 h, the reaction mixture was diluted with ethyl acetate (100 mL) and washed with water (100 mL). The aqueous layer was extracted with ethyl acetate (2×50 mL). The combined organic layer was washed with NaHCO3 (3×50 mL) followed by 10% LiCl (50 mL). The organic layer was dried, filtered and concentrated to afford 5-amino-2,4-difluoro-N-methylbenzamide (0.76 g, 41%) as a light brownish solid. MS (M+H)+=187. It was used without further purification (>92% pure by HPLC).

1. customat RT
2. washwashed with water (100 mL)
3. extractionThe aqueous layer was extracted with ethyl acetate (2×50 mL)
4. washThe combined organic layer was washed with NaHCO3 (3×50 mL)
5. customThe organic layer was dried
6. filtrationfiltered
7. concentrationconcentrated