反应 #65401

反应方程式

3,4-dihydro-2,2-dimethyl-6-nitro-3-oxo-2H-1,4-benzoxazine

sodium hydride

phenacyl bromide

→

3,4-dihydro-2,2-dimethyl-6-nitro-3-oxo-4-phenacyl-2H-1,4-benzoxazine

收率 66.6%

溶剂

N,N-dimethylformamide

反应条件

后处理

1. 1
   workup.STIRRINGThe mixture was stirred at room temperature for 1 hour
2. 2
   workup.DISTILLATIONafter which the solvent was distilled off under reduced pressure
3. 3
   workup.ADDITIONThe residue was diluted with 50 ml of water
4. 4
   萃取extracted with ethyl acetate
5. 5
   干燥The extract was dried over anhydrous magnesium sulfate
6. 6
   浓缩concentrated under reduced pressure
7. 7
   其他The residue was chromatographed on a silica gel column and elution
8. 8
   其他Recrystallization from ethyl acetate-ether

实验过程

In an argon gas stream, 2.0 g of 3,4-dihydro-2,2-dimethyl-6-nitro-3-oxo-2H-1,4-benzoxazine was added gradually to 0.4 g of 60% sodium hydride in oil in 40 ml of dry N,N-dimethylformamide. The mixture was stirred at room temperature for 1 hour and 2.68 g of phenacyl bromide was added. The mixture was stirred at room temperature for 1 hour, after which the solvent was distilled off under reduced pressure. The residue was diluted with 50 ml of water and extracted with ethyl acetate. The extract was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was chromatographed on a silica gel column and elution was carried out with methylene chloride-ethyl acetate. Recrystallization from ethyl acetate-ether gave 2.04 g of 3,4-dihydro-2,2-dimethyl-6-nitro-3-oxo-4-phenacyl-2H-1,4-benzoxazine.

来源