Реакция #8253

Уравнение реакции

sodium bicarbonate

Pyridine

5-Amino-2-(4-methylimidazol-1-yl)fluorobenzene

benzyl chloroformate

→

title product

Выход 92.9%

5-Benzyloxycarbonylamino-2-(4-methylimidazol-1-yl)fluorobenzene

Выход 92.9%

Растворители

dichloromethane

Условия реакции

Обработка

1. 1
   Температураcooled to −5°
2. 2
   Другоеthe organic layer separated
3. 3
   Экстракцияthe aqueous layer re-extracted with dichloromethane (2×200 ml)
4. 4
   Сушкаcombined organics dried (magnesium sulfate)
5. 5
   ФильтрацияAfter filtration and evaporation
6. 6
   Другоеthe residue was recrystallised from toluene (300 ml)

Методика

5-Amino-2-(4-methylimidazol-1-yl)fluorobenzene (50.6 g, 0.265 M) was dissolved in dry dichloromethane (800 ml) under nitrogen, and cooled to −5°. Pyridine (26.1 g, 0.33 M) was added, followed by benzyl chloroformate (49.9 g, 0.292 M) over 30 minutes. The mixture was stirred and the temperature allowed to rise to ambient over 16 hours. Aqueous sodium bicarbonate (5%, 350 ml) was added, the organic layer separated, and the aqueous layer re-extracted with dichloromethane (2×200 ml), and combined organics dried (magnesium sulfate). After filtration and evaporation, the residue was recrystallised from toluene (300 ml) to give title product (80 g).

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