反应详情

22.8 ml (80 mmol) of a 3.5 molar solution of sodium bis-(2-methoxyethoxy)-dihydroaluminate in toluene are added under nitrogen to a solution of 4.6 g (11.4 mmol) of the compound from Example 3 in 100 ml of dry tetrahydrofuran at -10° C. to -5° C. The mixture is stirred overnight at room temperature and then warmed to 40° C. for 5 h. After cooling again to 0° C., 100 ml of water are cautiously added dropwise and the mixture is extracted three times using 100 ml of ethyl acetate each time. The combined organic phases are washed with saturated sodium chloride solution, dried over magnesium sulphate and concentrated in vacuo. The residue is chromatographed on a column (100 g of silica gel 70-230 mesh, φ3.5 cm, using ethyl acetate/petroleum ether (6:4)).

1. temperaturewarmed to 40° C. for 5 h
2. temperatureAfter cooling again to 0° C.
3. extractionthe mixture is extracted three times
4. washThe combined organic phases are washed with saturated sodium chloride solution
5. dry with materialdried over magnesium sulphate
6. concentrationconcentrated in vacuo
7. customThe residue is chromatographed on a column (100 g of silica gel 70-230 mesh, φ3.5 cm, using ethyl acetate/petroleum ether (6:4))