Реакция #2467963

Уравнение реакции

water

ammonium hydroxide

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

→

product

Выход 53.0%

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

Выход 53.0%

Растворители

THF

Условия реакции

Обработка

1. 1
   workup.ADDITIONThe solution was poured into ice
2. 2
   Экстракцияextracted with ethyl acetate (3×50 mL)
3. 3
   ПромывкаThe combined EtOAc layer was washed with water, brine
4. 4
   Сушкаdried over sodium sulfate
5. 5
   ФильтрацияThe solution was filtered
6. 6
   Другоеevaporated the solvent
7. 7
   ДругоеThe residue was chromatographed over silica gel column

Методика

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)+.

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