反应详情

0.18 ml (1.65 mmol) of methyl acetoacetate in 5 ml of dry tetrahydrofuran are added dropwise at -5° C. under nitrogen to a suspension of 67 mg (2.2 mmol) of 80% pure sodium hydride in 10 ml of dry tetrahydrofuran. After 15 min, 1.01 ml (1.65 mmol) of 15% strength butyllithium in n-hexane are added dropwise at the same temperature and the mixture is then stirred for 15 minutes. 410 mg (1.1 mmol) of the compound from Example 4, dissolved in 10 ml of dry tetrahydrofuran, are then added and the mixture is stirred at -5° C. for 30 minutes. 0.3 ml of glacial acetic acid is cautiously added to the reaction solution, it is diluted with 100 ml of water and the mixture is extracted 3 times with 100 ml of ether each time. The combined organic phases are washed twice with saturated sodium hydrogencarbonate solution, dried over magnesium sulphate and concentrated in vacuo. The residue is filtered through silica gel (solvent: ethyl acetate/ petroleum ether 1:1).

1. additionare then added
2. stirringthe mixture is stirred at -5° C. for 30 minutes
3. extractionthe mixture is extracted 3 times with 100 ml of ether each time
4. washThe combined organic phases are washed twice with saturated sodium hydrogencarbonate solution
5. dry with materialdried over magnesium sulphate
6. concentrationconcentrated in vacuo
7. filtrationThe residue is filtered through silica gel (solvent: ethyl acetate/ petroleum ether 1:1)