Reaktion #66351

Reaktionsgleichung

6-(3-Nitro-phenyl)-7-pyridin-4-yl-2,3-dihydro-pyrazolo[5,1-b]thiazole

dioxane water

ammonium chloride

→

3-(7-pyridin-4-yl-2,3-dihydro-pyrazolo[5,1-b]thiazol-6-yl)-phenylamine

Ausbeute 73.4%

Lösungsmittel

water

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto cool to room temperature
2. 2
   Extraktionextracted with ethyl acetate (3×20 mL)
3. 3
   WaschenThe combined organic layers were washed with saturated aqueous NaHCO3 and brine
4. 4
   Sonstigedried
5. 5
   Einengenconcentrated to dryness

Vorschrift

6-(3-Nitro-phenyl)-7-pyridin-4-yl-2,3-dihydro-pyrazolo[5,1-b]thiazole (150 mg, 0.463 mmol) was suspended in a 5:1 dioxane/water mixture (3 mL). Zinc powder (121 mg, 1.852 mmol, 4 eq) was added, followed by ammonium chloride (247 mg, 4.63 mmol, 10 eq) and the mixture was heated to 100° C. and stirred at the same temperature for 2 hours. The reaction mixture was then allowed to cool to room temperature and diluted with water and ethyl acetate. The aqueous phase was basified by adding solid Na2HPO4 and extracted with ethyl acetate (3×20 mL). The combined organic layers were washed with saturated aqueous NaHCO3 and brine, dried and concentrated to dryness. 100 mg of 3-(7-pyridin-4-yl-2,3-dihydro-pyrazolo[5,1-b]thiazol-6-yl)-phenylamine were obtained as off-white solid (73%).

Quelle