Reaktion #88357

Reaktionsgleichung

Methyl chloroformate

2,4-difluoro-phenylamine

pyridine

→

desired compound

Ausbeute 98.0%

(2,4-Difluoro-Phenyl)-Carbamic Acid Methyl Ester

Ausbeute 98.0%

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwhile cooling
2. 2
   Einengenconcentrated under vacuum
3. 3
   workup.ADDITIONThe resulting material is diluted with 250 mL of water
4. 4
   Extraktionextracted with 3×250 mL of ethyl acetate
5. 5
   Trocknendried over magnesium sulfate
6. 6
   Filtrationfiltered
7. 7
   Einengenthe filtrate concentrated under vacuum
8. 8
   Filtrationthe resulting solid is collected by filtration
9. 9
   Sonstigedried

Vorschrift

Into a reaction flask under nitrogen, 2,4-difluoro-phenylamine (1, 50.00 g, 390 mmol) is combined with 550 mL of anhydrous dichloromethane and anhydrous pyridine (61.27 g, 770 mmol). Methyl chloroformate (43.92 g, 460 mmol) is added dropwise while cooling to maintain the temperature in the range of 20-30° C. The reaction is stirred overnight, then concentrated under vacuum. The resulting material is diluted with 250 mL of water, adjusted to pH 2 with 2M hydrochloric acid, and extracted with 3×250 mL of ethyl acetate. The organic layers are combined, dried over magnesium sulfate, filtered and the filtrate concentrated under vacuum. The resulting material is slurried from hexane and the resulting solid is collected by filtration and dried to provide the desired compound (2, 71.06 g, 98%).

Quelle