反应详情

温度

190 °C

3.6 g (0.019 mol) of 4-(2-thienyl)-4-keto-butyric acid, 2.74 ml (0.07 mol) of hydrazine 98%, 3.69 g (0.066 mol) of potash and 42 ml of diethylene glycol are placed in a two-necked flask equipped with a magnetic stirrer. The medium is heated for 7 h at 190° C. The medium is a clear uniform yellow. When it has cooled to room temperature it is hydrolysed with 200 ml of water. The diethylene glycol is extracted with 5 times 100 ml of ether. The aqueous phase is then acidified to pH 1 and extracted. The acid is absorbed in a solution of soda 5% washed with ether then acidified and absorbed for the last time in ether which is dried over MgSO4 and concentrated. 2.74 g of a clear yellow oil is obtained. Yield=85%.

1. customequipped with a magnetic stirrer
2. temperatureWhen it has cooled to room temperature it
3. extractionThe diethylene glycol is extracted with 5 times 100 ml of ether
4. extractionextracted
5. customThe acid is absorbed in a solution of soda 5%
6. washwashed with ether
7. customabsorbed for the last time in ether which
8. dry with materialis dried over MgSO4
9. concentrationconcentrated