Potassium Iodide → 2-Iodo-3-nitropyridine

Temperatur

0 °C

To a solution of 2-amino-3-nitro-pyridine (8 g, 57.5 mmol) in 60 mL of 6 N HCl cooled to 0° C. is added dropwise a solution of sodium nitrite (6.35 g, 92 mmol) in 40 mL of water. The mixture is stirred at 0° C. for 1.5 hours. Then a solution of potassium iodide (22.9 g, 138 mmol) in 40 mL of water is added dropwise to the yellow solution. The resulting red mixture is stirred at 0° C. for 30 minutes and then heated at 60° C. for 45 minutes. After cooling, the mixture is made basic by the careful addition of 3 N NaOH. The aqueous layer is extracted with CH2Cl2 (4×) and the combined organic layers are washed with 1 N HCl, dilute Na2SO3 and water. The organic layer is dried over MgSO4, filtered and concentrated in vacuo. The crude product (2.72 g, 10.9 mmol) is used in the subsequent step without further purification.

1. stirringThe resulting red mixture is stirred at 0° C. for 30 minutes
2. temperatureheated at 60° C. for 45 minutes
3. temperatureAfter cooling
4. extractionThe aqueous layer is extracted with CH2Cl2 (4×)
5. washthe combined organic layers are washed with 1 N HCl, dilute Na2SO3 and water
6. dry with materialThe organic layer is dried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo

ORD-Eintrag

ord-549b9f8b6bf54136979972c37969159d

Quelldatensatz

uspto-grants-2001_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06281227B1