反应详情

38 ml of a 1.5M lithium diisopropylamide cyclohexane solution was dissolved in 400 ml of tetrahydrofuran, and 20 ml of a tetrahydrofuran solution containing 10.3 g of diisopropyl glutarate was dropwise added at -78° C. in a nitrogen atmosphere. After stirring at the same temperature for 30 minutes, 10 ml of a tetrahydrofuran solution containing 3.9 g of benzaldehyde was dropwise added thereto, followed by stirring at -78° C. for 1.5 hours. 2N hydrochloric acid was added to the reaction solution, and the temperature was brought to room temperature. Then, the mixture was extracted with ethyl acetate. The organic layer was washed with 1N hydrochloric acid, a saturated sodium hydrogencarbonate aqueous solution and a saturated sodium chloride aqueous solution and dried over anhydrous magnesium sulfate. The drying agent was filtered off, and then, the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate=5/1→3/1) to obtain 6.14 g of the above-identified compound as a colorless oily substance.

1. additionwas dropwise added at -78° C. in a nitrogen atmosphere
2. additionwas dropwise added
3. stirringby stirring at -78° C. for 1.5 hours
4. customwas brought to room temperature
5. extractionThen, the mixture was extracted with ethyl acetate
6. washThe organic layer was washed with 1N hydrochloric acid
7. dry with materiala saturated sodium hydrogencarbonate aqueous solution and a saturated sodium chloride aqueous solution and dried over anhydrous magnesium sulfate
8. filtrationThe drying agent was filtered off
9. distillationthe solvent was distilled off under reduced pressure
10. customThe residue was purified by silica gel column chromatography (hexane/ethyl acetate=5/1→3/1)