反应详情

21 ml (80.5 mmol) of a 3.5 molar solution of sodium bis-(2-methoxy ethoxy)-dihydroaluminate in toluene are added at -10° C. to -5° C. under nitrogen to a solution of 9.2 g (23 mmol) of the compound from Example III in 100 ml of dry tetrahydrofuran and the mixture is stirred at room temperature for 5 h. After cooling to 0° C., 100 ml of water are cautiously added dropwise and the mixture is extracted 3 times with 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 (200 g of silica gel 70-230 mesh, φ 4.5 cm, using ethyl acetate/petroleum ether 3:7).

1. temperatureAfter cooling to 0° C.
2. extractionthe mixture is extracted 3 times with 100 ml of ethyl acetate each time
3. washThe combined organic phases are washed with saturated sodium chloride solution
4. dry with materialdried over magnesium sulphate
5. concentrationconcentrated in vacuo
6. customThe residue is chromatographed on a column (200 g of silica gel 70-230 mesh, φ 4.5 cm, using ethyl acetate/petroleum ether 3:7)