反应详情

tert-Butyl 4-amino(hydroxyimino)methyl-2-fluorobenzoate (WO 2011/016469) (3.90 g, 17.6 mmol) was dissolved in ethanol (40 mL) and acetic acid (40 mL). Raney nickel (ca. 10 g) was added to the mixture at room temperature, and the resulting mixture was stirred for 1 hour under hydrogen flow. After the insoluble material was removed by filtration through Celite, water was added to the filtrate, and the resulting mixture was extracted three times with ethyl acetate, and then dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and then water and a saturated aqueous solution of sodium hydrogen carbonate were added to the mixture. The resulting mixture was extracted with ethyl acetate, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=95:5→2:1, v/v) to give the title compound (2.21 g, yield: 56%).

1. customAfter the insoluble material was removed by filtration through Celite, water
2. additionwas added to the filtrate
3. extractionthe resulting mixture was extracted three times with ethyl acetate
4. dry with materialdried over anhydrous sodium sulfate
5. distillationThe solvent was distilled off under reduced pressure
6. additionwater and a saturated aqueous solution of sodium hydrogen carbonate were added to the mixture
7. extractionThe resulting mixture was extracted with ethyl acetate
8. dry with materialdried over anhydrous sodium sulfate
9. distillationThe solvent was distilled off under reduced pressure
10. customthe resulting residue was purified by silica gel column chromatography (hexane