反应详情

To a 100 ml round bottom flask, 6-chloropyrazine-2-carboxylic acid (1 g, 6.31 mmol) was suspended in dry CH2Cl2 (30 ml). Oxalyl chloride (3.78 ml, 7.57 mmol) was added along with a few drop of DMF, the mixture was stirred at room temperature for 12 hrs, N,O-Dimethylhydroxylamine hydrochloride (0.800 g, 8.20 mmol) was added, the resulting mixture was cooled down to 5° C., TEA (2.64 ml, 18.92 mmol) was added via a dropping funnel, the reaction mixture was stirred at room temperature for 30 minutes, filtered and the filter cake was washed with EtOAc, the combined filtrate was washed with saturated sodium bicarbonate and brine, concentrated to an oil, purified on silica gel with Hexanes/EtOAc solvents to give product (1.06 g).

1. temperaturethe resulting mixture was cooled down to 5° C.
2. stirringthe reaction mixture was stirred at room temperature for 30 minutes
3. filtrationfiltered
4. washthe filter cake was washed with EtOAc
5. washthe combined filtrate was washed with saturated sodium bicarbonate and brine
6. concentrationconcentrated to an oil
7. custompurified on silica gel with Hexanes/EtOAc solvents