Reacción #2467963

Ecuación de reacción

water

ammonium hydroxide

methyl 3-[(dimethylamino)diazenyl]-4-bromothiophene-2-carboxylate

→

product

Rendimiento 53.0%

3-[(Dimethylamino)diazenyl]-4-bromothiophene-2-carboxamide

Rendimiento 53.0%

Disolventes

THF

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONThe solution was poured into ice
2. 2
   Extracciónextracted with ethyl acetate (3×50 mL)
3. 3
   LavadoThe combined EtOAc layer was washed with water, brine
4. 4
   Secadodried over sodium sulfate
5. 5
   FiltraciónThe solution was filtered
6. 6
   Otroevaporated the solvent
7. 7
   OtroThe residue was chromatographed over silica gel column

Procedimiento

To an ice cold (0-5° C.) solution of ammonium hydroxide (10 mL) was added a solution of methyl 3-[(dimethylamino)diazenyl]-4-bromothiophene-2-carboxylate (500 mg) in THF (5 mL) for 5 min and stirred at rt for 20 h. The solution was poured into ice cooled water and extracted with ethyl acetate (3×50 mL). The combined EtOAc layer was washed with water, brine and dried over sodium sulfate. The solution was filtered and evaporated the solvent. The residue was chromatographed over silica gel column using chloroform-methanol (98:2) as eluents to give the product as an off-white solid (250 mg, 53%), mp 194-196° C. 1H NMR (400 MHz, DMSO-d6): δ 7.85 (1H, s), 7.75 (1H, br s), 7.56 (1H, br s), 3.56 (3H, br s), 3.21 (3H, br s); LC-MS (positive ion mode): m/z 277, 279 (M+H)+.

Fuente