反应详情

温度

-60 °C

A solution of tetrahydrofuran (2000 ml) containing lithium aluminum hydride (46 g, 1.21 moles) is cooled in a -60° C. dry ice/ethanol bath. Ethyl 5-ethoxyheptanoate (302 g, 1.49 moles) is diluted in tetrahydrofuran (300 ml) and added dropwise to the stirring reaction. After the addition is complete the reaction is warmed to room temperature and stirred an additional hour. The solution is again cooled in a -78° C. dry ice/ethanol bath and the excess hydride is destroyed by adding dropwise the following: water (46 ml), 15% sodium hydroxide solution (46 ml), and water (136 ml). The reaction is filtered and the solids washed several times with tetrahydrofuran (3×500 ml). The volume of the filtrate is reduced under vacuum and the residue dried over anhydrous magnesium sulfate. The remaining solvent is then removed leaving a clear, colorless oil suitably pure for the next reaction (238 g, 1.49 moles).

1. additionadded dropwise to the stirring reaction
2. additionAfter the addition
3. temperatureis warmed to room temperature
4. temperatureThe solution is again cooled in a -78° C. dry ice/ethanol bath
5. customthe excess hydride is destroyed
6. additionby adding dropwise the following: water (46 ml), 15% sodium hydroxide solution (46 ml), and water (136 ml)
7. filtrationThe reaction is filtered
8. washthe solids washed several times with tetrahydrofuran (3×500 ml)
9. dry with materialthe residue dried over anhydrous magnesium sulfate
10. customThe remaining solvent is then removed
11. customleaving a clear, colorless oil
12. customsuitably pure for the next reaction (238 g, 1.49 moles)