Réaction #8249

Équation de réaction

sodium bicarbonate

Pyridine

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

benzyl chloroformate

→

title product

Rendement 93.5%

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

Rendement 93.5%

Solvants

dichloromethane

Conditions de réaction

Traitement

1. 1
   Températurecooled to −5°
2. 2
   Autrethe organic layer separated
3. 3
   Extractionthe aqueous layer re-extracted with dichloromethane (2×300 ml)
4. 4
   Séchagedried (magnesium sulfate)
5. 5
   FiltrationAfter filtration and evaporation
6. 6
   Autrethe residue was recrystallised from toluene (400 ml)

Mode opératoire

5-Amino-2-(2-methylimidazol-1-yl)fluorobenzene (34.25 g, 0.179 M) was dissolved in dry dichloromethane (600 ml) under nitrogen, and cooled to −5°. Pyridine (17.7 g, 0.224 M) was added, followed by benzyl chloroformate (33.7 g, 0.197 M) over 20 minutes. The mixture was stirred and the temperature allowed to rise to ambient over 16 hours. Aqueous sodium bicarbonate (5%, 250 ml) was added, the organic layer separated, the aqueous layer re-extracted with dichloromethane (2×300 ml), and combined extracts dried (magnesium sulfate). After filtration and evaporation, the residue was recrystallised from toluene (400 ml) to give title product (54.5 g).

Source