反应详情

To a solution of 2-chloro-3-fluorobenzoic acid (3.32 g, 19.02 mmol) in DMF (60 mL) was added N,O-dimethylhydroxylamine hydrochloride, 98% (2.30 g, 23.58 mmol), O-(-7-azabenzotriazol-1-yl)-N,′N,′N,′N′-tetramethyluronium-hexafluorophosphate (HATU) (8.82 g, 23.20 mmol) and triethylamine (6.63 mL, 47.5 mmol). The mixture was stirred at rt for 3 h. The reaction was quenched with saturated Na2CO3 and extracted with EtOAc. The organic solution was washed with water and brine, dried over Na2SO4, filtered, and concentrated in vacuo. The crude was purified by flash chromatography on silica gel (80 g, 10-100% EtOAc/hexane in 25 min) to give 2-chloro-3-fluoro-N-methoxy-N-methylbenzamide as colorless oil, which turned to solid on vacuum (3.95 g, 95% yield). MS m/z=218 [M+H]+. Calculated for C9H9ClFNO2: 217.6.

1. customThe reaction was quenched with saturated Na2CO3
2. extractionextracted with EtOAc
3. washThe organic solution was washed with water and brine
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe crude was purified by flash chromatography on silica gel (80 g, 10-100% EtOAc/hexane in 25 min)