反応 #2467963

反応方程式

water

ammonium hydroxide

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

→

product

収率 53.0%

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

収率 53.0%

溶媒

THF

反応条件

後処理

1. 1
   workup.ADDITIONThe solution was poured into ice
2. 2
   抽出extracted with ethyl acetate (3×50 mL)
3. 3
   洗浄The combined EtOAc layer was washed with water, brine
4. 4
   乾燥dried over sodium sulfate
5. 5
   ろ過The solution was filtered
6. 6
   その他evaporated the solvent
7. 7
   その他The residue was chromatographed over silica gel column

実験手順

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)+.

出典