Reacción #1726702

Ecuación de reacción

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

lithium bis(trimethylsilyl)amide

hydrochloric acid

→

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

Rendimiento 68.0%

Disolventes

THF

THF

Condiciones de reacción

Tratamiento posterior

1. 1
   Extracciónextracted three times into ether (total 300 ml)
2. 2
   LavadoThe combined organic phases were washed with saturated aqueous sodium bicarbonate and brine
3. 3
   Secadodried over magnesium sulfate
4. 4
   Concentraciónconcentrated in vacuo
5. 5
   workup.DISSOLUTIONThe residue was dissolved in methanol (50 ml)
6. 6
   Temperaturatriethylamine (0.5 ml) was heated
7. 7
   Temperaturato reflux for 15 hr
8. 8
   Concentraciónagain concentrated in vacuo

Procedimiento

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.

Fuente