Reacción #156282

Ecuación de reacción

sodium hydroxide

water ethyl acetate

(2E)-1-(4-bromo-2-nitrophenyl)-3-(dimethylamino)prop-2-en-1-one

cyclopentylhydrazine hydrochloride

→

5-(4-bromo-2-nitrophenyl)-1-cyclopentyl-1H-pyrazole

Rendimiento 72.7%

Disolventes

acetic acid

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe aqueous layer was separated
2. 2
   Lavadothe organic layer was washed with water and saturated brine
3. 3
   Secadodried over anhydrous magnesium sulfate
4. 4
   OtroThe solvent was evaporated under reduced pressure
5. 5
   Otrothe residue was purified by silica gel column chromatography (n-hexane/ethyl acetate)

Procedimiento

Under a nitrogen atmosphere, to a solution of 1.15 g of (2E)-1-(4-bromo-2-nitrophenyl)-3-(dimethylamino)prop-2-en-1-one in 9.2 mL of acetic acid was added 1.05 g of cyclopentylhydrazine hydrochloride, followed by stirring at room temperature for 60 hours. The reaction mixture was poured into a mixture of water/ethyl acetate, followed by adjusting to pH 10 with a 6 M aqueous sodium hydroxide solution. The aqueous layer was separated, and then the organic layer was washed with water and saturated brine, and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure, and then the residue was purified by silica gel column chromatography (n-hexane/ethyl acetate) to obtain 940 mg of 5-(4-bromo-2-nitrophenyl)-1-cyclopentyl-1H-pyrazole.

Fuente