反应 #45022

反应方程式

tert-butyl 4-(5-formylthien-2-yl)piperazine-1-carboxylate

sodium hydroxide

→

5-[4-[(2-methylpropan-2-yl)oxycarbonyl]piperazin-1-yl]thiophene-2-carboxylic acid

收率 71.0%

溶剂

ethanol

water

反应条件

后处理

1. 1
   温度The mixture was cooled by the addition of ice
2. 2
   过滤filtered
3. 3
   其他to remove silver salts
4. 4
   其他The filtrate was carefully evaporated
5. 5
   其他to remove the ethanol
6. 6
   过滤the resulting aqueous solution was filtered again through a glass-fibre pad
7. 7
   其他to remove tarry material
8. 8
   workup.ADDITIONThe filtrate was then diluted with water to a total volume of 400 ml
9. 9
   过滤The precipitate was filtered off
10. 10
    洗涤washed with water
11. 11
    其他dried in a vacuum oven at 45° C. overnight

实验过程

A solution of tert-butyl 4-(5-formylthien-2-yl)piperazine-1-carboxylate (2.5 1 g, 8.50 mmol) in ethanol (85 ml) was added in one portion to a solution of silver (I) nitrate (10.0 g, 58.8 mmol) and sodium hydroxide (4.83 g, 120.6 mmol) in water (85 ml). This mixture was stirred and heated at 65° C. for 22 h. The mixture was cooled by the addition of ice and then filtered to remove silver salts. The filtrate was carefully evaporated to remove the ethanol and the resulting aqueous solution was filtered again through a glass-fibre pad to remove tarry material. The filtrate was then diluted with water to a total volume of 400 ml and then acidified to pH 5 with acetic acid. The precipitate was filtered off, washed with water and then dried in a vacuum oven at 45° C. overnight to give 5-[4-[(2-methylpropan-2-yl)oxycarbonyl]piperazin-1-yl]thiophene-2-carboxylic acid (1.88 g, 71%).

来源