Phosphorus oxychloride → 4-Chloro-3-nitropyridine

4-Hydroxy-3-nitropyridine (10.0 g, 71.38 mmol) was added to 100 ml of phosphorus oxychloride, which was then refluxed under stirring for 1 hour. The reaction mixture was concentrated under reduced pressure. The resulting residue was added to 500 ml of ice water, which was then neutralized with 2N sodium hydroxide solution. The reaction mixture was extracted with methylene chloride (300 ml). The separated organic layer was dried on anhydrous magnesium sulfate and concentrated under reduced pressure to give the titled compound of a pale yellow solid (9.2 g, 92.0%).

1. temperaturewas then refluxed
2. concentrationThe reaction mixture was concentrated under reduced pressure
3. additionThe resulting residue was added to 500 ml of ice water, which
4. extractionThe reaction mixture was extracted with methylene chloride (300 ml)
5. dry with materialThe separated organic layer was dried on anhydrous magnesium sulfate
6. concentrationconcentrated under reduced pressure

ORD record

ord-4da74520e1454166b6df961425abe916

Source dataset

uspto-grants-2010_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07642269B2