反应 #1540825

反应方程式

methyl 3-bromo-5-methoxy-4-aminobenzoate

sodium nitrite

hypophosphoric acid

→

methyl 3-bromo-5-methoxybenzoate

收率 100.2%

溶剂

ethanol

sulfuric acid

acetic acid

water

water

反应条件

后处理

1. 1
   其他A 500 ml round bottom flask fitted with overhead
2. 2
   温度The solution was chilled in an ice bath
3. 3
   温度while maintaining the temperature below 10° C
4. 4
   workup.STIRRINGAfter stirring an additional 25 minutes
5. 5
   workup.STIRRINGthe mixture was stirred cold for 2 hours
6. 6
   萃取extracted with ether
7. 7
   其他evaporated under reduced pressure

实验过程

A 500 ml round bottom flask fitted with overhead stirring was charged with 16.5 grams (55 mmole) of methyl 3-bromo-5-methoxy-4-aminobenzoate in 80 ml ethanol, 15 ml sulfuric acid and 20 ml acetic acid. The solution was chilled in an ice bath and 6.6 gms (95 mmole) of sodium nitrite in 30 ml water was added dropwise while maintaining the temperature below 10° C. After stirring an additional 25 minutes, 100 ml of 50% hypophosphoric acid was added and the mixture was stirred cold for 2 hours. The reaction mixture was diluted with 500 ml water, extracted with ether, and then evaporated under reduced pressure to give 13.5 grams of methyl 3-bromo-5-methoxybenzoate as a reddish-oil.

来源