Réaction #1726702

Équation de réaction

3-Chloro-4-phenyl-1,2,5-thiadiazole

lithium bis(trimethylsilyl)amide

hydrochloric acid

→

3-amino-4-phenyl-1,2,5-thiadiazole

Rendement 68.0%

Solvants

THF

THF

Conditions de réaction

Traitement

1. 1
   Extractionextracted three times into ether (total 300 ml)
2. 2
   LavageThe combined organic phases were washed with saturated aqueous sodium bicarbonate and brine
3. 3
   Séchagedried over magnesium sulfate
4. 4
   Concentrationconcentrated in vacuo
5. 5
   workup.DISSOLUTIONThe residue was dissolved in methanol (50 ml)
6. 6
   Températuretriethylamine (0.5 ml) was heated
7. 7
   Températureto reflux for 15 hr
8. 8
   Concentrationagain concentrated in vacuo

Mode opératoire

3-Chloro-4-phenyl-1,2,5-thiadiazole (3.19 g, 16.2 mmol) in THF (32 ml) at 0° C. was treated dropwise with a solution of lithium bis(trimethylsilyl)amide in THF (17.0 ml, 1.0 M, 17.0 mmol). After 10 min the mixture allowed to warm to ambient temperature for 1.5 hr, treated with 1N hydrochloric acid, and extracted three times into ether (total 300 ml). The combined organic phases were washed with saturated aqueous sodium bicarbonate and brine, and dried over magnesium sulfate and concentrated in vacuo. The residue was dissolved in methanol (50 ml) and triethylamine (0.5 ml) was heated to reflux for 15 hr and again concentrated in vacuo. Flash chromatography on silica gel (ethyl acetate/hexanes) yielded 3-amino-4-phenyl-1,2,5-thiadiazole (1.96 g, 68%) as a colorless solid.

Source