反应详情

2-chloro-4-methyl-5-nitropyridine (1.0 g, 5.8 mmol) was cooled using an ice water bath. Sodium dichromate dihydrate (3.45 g, 11.6 mmol) dissolved in sulphuric acid (50 mL) was added dropwise, ensuring reaction temperature does not exceed 15° C. After complete addition, reaction allowed to warm to room temperature and stirred overnight. Quenched with ice, extracted into ethylacetate and concentrated under reduced pressure to afford 2-chloro-5-nitroisonicotinic acid (1.3 g, 6.4 mmol).

1. additionwas added dropwise
2. customreaction temperature
3. customdoes not exceed 15° C
4. additionAfter complete addition, reaction
5. customQuenched with ice
6. extractionextracted into ethylacetate
7. concentrationconcentrated under reduced pressure