反应详情

Oxalyl chloride (3.78 mL, 0.0441 mmol) and N,N-dimethylformamide (0.06 mL) were added to a chloroform (20 mL) solution of 5-bromo-2-chlorobenzoic acid (10.0 g, 0.0425 mol). After the reaction mixture was stirred at room temperature for one day, the reaction mixture was evaporated under reduced pressure. The obtained yellow oily substance was dissolved in chloroform (20 mL). This solution was added dropwise to a mixture of N,O-dimethoxyhydroxylamine hydrochloride (4.56 g, 0.0468 mol), triethylamine (12.3 mL, 0.0882 mol) and chloroform (50 mL) for 15 minutes, while maintaining the reaction temperature at 5° C. to 10° C. After stirred for 15 minutes, the reaction mixture was warmed to room temperature. After water (20 mL) was added to the reaction mixture, the organic layer was separated and the organic layer was washed with a saturated sodium bicarbonate aqueous solution and brine, and then dried with anhydrous magnesium sulfate. After the desiccant was filtered off, the solvent was evaporated under reduced pressure to obtain 5-bromo-2-chloro-N-methoxy-N-methylbenzamide (11.8 g, 99.7%) as a colorless crystal. This was used in the next reaction without purification.

1. customthe reaction mixture was evaporated under reduced pressure
2. dissolutionThe obtained yellow oily substance was dissolved in chloroform (20 mL)
3. temperaturewhile maintaining the reaction temperature at 5° C. to 10° C
4. stirringAfter stirred for 15 minutes
5. temperaturethe reaction mixture was warmed to room temperature
6. customthe organic layer was separated
7. washthe organic layer was washed with a saturated sodium bicarbonate aqueous solution and brine
8. dry with materialdried with anhydrous magnesium sulfate
9. filtrationAfter the desiccant was filtered off
10. customthe solvent was evaporated under reduced pressure