反应详情

4.2 mL (46 mmol) phosphorus oxychloride in 20 mL DCM were added dropwise at 10° C. to 3.6 g (15 mmol) 5-bromo-2-methyl-4-nitropyridine-1-oxide in 30 mL DCM. The reaction mixture was then refluxed for 5 h, then added to ice water and adjusted to a pH of 10 with 4N aqueous sodium hydroxide solution. The organic phase was separated off and the aqueous phase was extracted twice more with DCM. The combined organic phases were dried on sodium sulphate and evaporated down. The residue was stirred into petroleum ether, the precipitate formed was suction filtered and dried.

1. temperatureThe reaction mixture was then refluxed for 5 h
2. customThe organic phase was separated off
3. extractionthe aqueous phase was extracted twice more with DCM
4. customThe combined organic phases were dried on sodium sulphate
5. customevaporated down
6. customthe precipitate formed
7. filtrationfiltered
8. customdried