反应 #88357

反应方程式

Methyl chloroformate

2,4-difluoro-phenylamine

pyridine

→

desired compound

收率 98.0%

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

收率 98.0%

溶剂

dichloromethane

反应条件

后处理

1. 1
   温度while cooling
2. 2
   浓缩concentrated under vacuum
3. 3
   workup.ADDITIONThe resulting material is diluted with 250 mL of water
4. 4
   萃取extracted with 3×250 mL of ethyl acetate
5. 5
   干燥dried over magnesium sulfate
6. 6
   过滤filtered
7. 7
   浓缩the filtrate concentrated under vacuum
8. 8
   过滤the resulting solid is collected by filtration
9. 9
   其他dried

实验过程

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%).

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